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Oxidative Stress

• Adverse Effects of Pesticides on the Ovary: Evidence from Epidemiological and Toxicological Studies
  Pesticides are widely used in agriculture, public health, and residences to control pests and insects. The safety of exposure to pesticides has raised concerns due to their presence in the environment and their potential effects on human health. The ovary is the major female reproductive organ and is considered a potential target organ for pesticide toxicity. This comprehensive Review examines the adverse effects of pesticide exposure on the ovary based on evidence from human biomonitoring, epidemiological studies, and toxicological studies. Epidemiological studies have shown that pesticide exposures are associated with early/delayed menarche, menstrual cycle disorders, early menopause, long time to pregnancy, polycystic ovary syndrome, primary ovarian insufficiency, infertility, and implantation failure in women. Both in vivo and in vitro studies have shown that exposure to pesticides disrupts the estrous cycle, reduces the follicle pool, alters hormone levels, and impairs oocyte maturation. Mechanisms of action of pesticides on ovarian function include effects on steroid receptors, hormone synthesis, oxidative stress, inflammation, epigenetic modifications, and signaling pathways. Gaps in knowledge and further research needs include prospective cohort studies with adequate sample sizes to elucidate the effects of different classes of pesticides (especially emerging insecticides, herbicides and fungicides) and mixture exposures on ovarian health, the development of effective toxicological models that can approximate or simulate realistic human exposure scenarios, and the translation of toxicological findings into measurable indicators that can be used in human health risk assessment. In summary, this Review aims to improve the understanding of the risk to women’s reproductive health from exposures to pesticides and to provide insights into strategies for preventing and managing reproductive health risks.
  [Wang, L., Ma, X. and Liu, J. (2025) Adverse Effects of Pesticides on the Ovary: Evidence from Epidemiological and Toxicological Studies, Environment & Health. Available at: https://pubs.acs.org/doi/full/10.1021/envhealth.4c00243.]
• Cardiotoxicity and triazole pesticides: therapeutic options for a neglected heart disease
  Triazoles are a class of fungicides that inhibit the biosynthesis of ergosterol, an essential component of fungal cell membranes. Compounds such as tebuconazole, propiconazole, and difenoconazole are among the most used triazoles in agriculture. Due to their efficacy and relatively low toxicity to plants and mammals at appropriate doses, these pesticides have become indispensable tools in agricultural management. Although their effectiveness as fungicides is well documented, there are growing concerns regarding their safety for human health, especially in long-term exposure. This letter addresses mostly the known mechanisms of cardiotoxicity of triazole pesticides in mammals and the possible treatment options available to mitigate these adverse effects.
  [Souza, D. and Roman-Campos, D. (2025) Cardiotoxicity and triazole pesticides: therapeutic options for a neglected heart disease, Expert Review of Cardiovascular Therapy. Available at: https://www.tandfonline.com/doi/full/10.1080/14779072.2025.2476124. ]
• Chlorpyrifos Induces Apoptosis in Macrophages by Activating Both Intrinsic and Extrinsic Apoptotic Pathways
  Although chlorpyrifos poses considerable risks to the environment and human health, it is still used in many countries. This pesticide has various toxic effects on humans, including neurotoxicity, reproductive toxicity, genotoxicity, and organ damage caused by oxidative stress and DNA damage. However, its specific toxicity to the immune system remains unclear. In this study, we explored the intrinsic and extrinsic apoptotic pathways through which chlorpyrifos induces apoptosis in macrophages. RAW 264.7 macrophages were treated with chlorpyrifos at concentrations of 0, 2, 4, 10, and 20 ppm for 3 h. Cytotoxicity was assessed using a lactate dehydrogenase assay, whereas apoptosis was evaluated through flow cytometry. The levels of cysteinyl aspartate-specific proteinase (caspase)-3, caspase-8, and caspase-9 were measured. The disruption of mitochondrial function and the expression of the death receptors Fas receptor and tumor necrosis factor-alpha receptor were assessed through JC-1 stain reagent. The release of mitochondrial cytochrome c, expression of Bcl2 family proteins, and level of cleaved caspases were analyzed through Western blotting. Chlorpyrifos induced cytotoxicity and apoptosis in a concentration-dependent manner. It activated caspase-3, caspase-8, and caspase-9, as well as disrupted mitochondrial function and Bcl2 family protein balance. Furthermore, chlorpyrifos induced the release of cytochrome c from the mitochondria and upregulated the expression of Fas receptor and tumor necrosis factor-alpha receptor. These findings suggest that chlorpyrifos induces cytotoxicity through caspase-3-dependent apoptosis via the intrinsic pathway (caspase-8 activation, mitochondrial dysfunction, Bcl2 protein imbalance, and cytochrome c release) and the extrinsic pathway (caspase-9 activation and death receptor expression).
  [Chiang, C.-Y. et al. (2025) Chlorpyrifos Induces Apoptosis in Macrophages by Activating Both Intrinsic and Extrinsic Apoptotic Pathways, Environmental Toxicology. Available at: https://onlinelibrary.wiley.com/doi/10.1002/tox.24515.]
• Combined Cytotoxic Effects of the Fungicide Azoxystrobin and Common Food-Contaminating Mycotoxins
  This study assessed the cytotoxicity of the individual and combined exposure to the fungicide azoxystrobin (AZX) and the three common mycotoxins found in food: ochratoxin A (OTA), deoxynivalenol (DON), and T-2 toxin. Cytotoxic effects were evaluated using the resazurin and MTT assays in human hepatocarcinoma (HepG2) cells after 24 h of exposure, and the type of interaction between the compounds was determined using the isobologram method. Results showed that T-2 was the most cytotoxic compound, followed by DON, OTA, and AZX. The compound ratios in the mixture were calculated using three sublethal concentrations (IC50/2, IC50/4, and IC50/8) to achieve equal toxicity for each compound. Interaction analysis revealed that the nature of the interaction varied across components and concentrations. The AZX and DON mixture produced an antagonistic effect at all the analyzed effect levels. AZX and OTA or T2 mixtures, and tertiary combinations displayed antagonism at low effect values but additivity at high effect levels. Importantly, the quaternary mixture demonstrated synergism at all the effect levels. These findings highlight that the co-occurrence of fungicides and mycotoxins in food commodities can lead to complex exposure scenarios that may result in combined toxic effects on the organism.
  [Fuentes, C. et al. (2025) Combined Cytotoxic Effects of the Fungicide Azoxystrobin and Common Food-Contaminating Mycotoxins, Foods. Available at: https://www.mdpi.com/2304-8158/14/7/1226.]
• Environmental exposure to pesticides is associated with oxidative stress, oxidative DNA damage, and elevated interleukin-8 in a child population
  Pesticide exposure can cause various adverse effects in humans, with children being particularly susceptible. Such exposure leads to neurological, immunological, respiratory, and genetic damage, primarily by generating reactive oxygen species (ROS). The increase in ROS induces lipid peroxidation (LPO) and the formation of hydroxyl radicals, which generate DNA adducts. This study involved children aged 6–12 from three communities: two in an agricultural region (communities A and B) and one reference population (community C). The objective was to evaluate lipid peroxidation through malondialdehyde (MDA) levels, the content of 8-hydroxy-2′-deoxyguanosine (8-OHdG) adducts, and the concentrations of the cytokines IL-6, IL-8, IL-10, and TNF-α in children environmentally exposed to pesticides. Anthropometric measurements were taken from the study population. Dialkylphosphates (DAP) in urine were determined by gas chromatography and mass spectrometry. Plasma concentrations of MDA and pro-inflammatory cytokines (IL-6, IL-8, TNF-α) and the anti-inflammatory cytokine (IL-10) were quantified using biochemical assays and urinary concentrations of 8-OHdG. The findings showed that DAP, MDA, and 8-OHdG concentrations in communities A and B increased significantly compared with community C. Additionally, IL-8 exhibited a significant increase in community A compared to community C, while no significant differences were observed for IL-6, IL-10, and TNF-α. Higher pesticide exposure is linked to oxidative stress, DNA damage and inflammation, key indicators of chronic diseases. In conclusion, this study provides evidence linking environmental pesticide exposure in agricultural communities to increased oxidative stress and inflammatory responses in children.
  [Aguilar-Bañuelos, J. A., Bernal-Hernández, Y. Y., Medina-Díaz, I. M., Ruiz-Arias, M. A., Herrera-Moreno, J. F., Barrón-Vivanco, B. S., González-Arias, C. A., Agraz-Cibrián, J. M., Zambrano-Zaragoza, J. F., Verdín-Betancourt, F. A., Ruiz, N. P., Flores-Alfaro, E., & Rojas-García, A. E. (2025). Environmental exposure to pesticides is associated with oxidative stress, oxidative DNA damage, and elevated interleukin-8 in a child population. Environmental toxicology and pharmacology, 104656. Advance online publication. https://doi.org/10.1016/j.etap.2025.104656]
• Fatal paraquat poisoning: a case report and literature review on rapid deterioration and therapeutic challenges
  Introduction and importance:
  Paraquat (PQ) poisoning is a life-threatening condition with a high-mortality rate. As it lacks a specific antidote, treatment is mainly supportive, focusing on reducing oxidative damage and organ dysfunction. Despite aggressive intervention, the condition can rapidly progress to multiorgan failure. This report presents a fatal case of PQ poisoning, highlighting its clinical course and management challenges.

  Case presentation:
  A 45-year-old female ingested 10 mL of 20% PQ, presenting with vomiting, dizziness, and generalized body aches. At presentation, she was alert, with stable vital signs and no significant findings. Immediate treatment, including gastric lavage, activated charcoal, corticosteroids, antioxidants, and monitoring of renal and hepatic function, was initiated. On Day 2, her condition deteriorated with jaundice, respiratory distress, and PQ-induced tongue ulcers. Lab results showed worsening renal and hepatic dysfunction. She received cyclophosphamide, N-acetylcysteine, and heparin-free hemodialysis, but her condition continued to decline, leading to multiorgan failure. She succumbed to her condition on the fourth day.

  Clinical discussion:
  PQ toxicity causes oxidative stress, resulting in rapid progression to multiorgan failure. Early decontamination and supportive care are key, but no curative treatment exists. The rapid progression and limited effectiveness of current therapies make management difficult.

  Conclusion:
  PQ poisoning remains a critical medical emergency with a high-mortality rate. Timely recognition, aggressive supportive care, and further research into novel detoxification and therapeutic strategies are essential to improving survival outcomes. Additionally, public health measures, including stricter regulations and increased awareness regarding PQ’s toxicity, are crucial in preventing future cases.
  [Barma, A. et al. (2025) Fatal paraquat poisoning: a case report and literature review on rapid deterioration and therapeutic challenges, Annals of Medicine & Surgery. Available at: https://journals.lww.com/annals-of-medicine-and-surgery/fulltext/2025/04000/fatal_paraquat_poisoning__a_case_report_and.82.aspx.]

• Hypothesis: glyphosate-based herbicides can increase risk of hematopoietic malignancies through extended persistence in bone
  Despite episodic and variable patterns of exposure, the levels of glyphosate (GLY) detected in the urine of herbicide applicators and the general public are relatively stable across space (urban vs. rural) and time (weed spray season, not spray season). Substantial GLY metabolism data show that within minutes of entering the bloodstream, GLY moves into bone marrow, and then laterally through bone tissue and back into general circulation. As GLY moves through bone it comes into contact with calcium and a portion is immobilized via chelation. A novel two-part hypothesis is explored: first, the likely reason for the lack of variability in GLY levels in urine is that GLY stored in bone is excreted gradually over days to weeks, and augments the generally stable and modest levels of dietary exposure to GLY; and second, the prolonged systemic movement of GLY into bone marrow and bone extends contact between GLY and hematopoietic stem cells (HSC), increasing the risk of GLY-induced breaks and rearrangements in the DNA in HSCs. Studies confirm that GLY and glyphosate-based herbicides (GBHs) can trigger oxidative stress and impair DNA-repair mechanisms. Animal bioassays and epidemiology studies link GLY/GBH exposures to heightened risk of blood cancers, and possibly other pathologies. The hypothesis proposed here provides a plausible pathophysiologic basis for these observations relative, in particular, to blood cancers.
  [Benbrook, C. (2025) Hypothesis: glyphosate-based herbicides can increase risk of hematopoietic malignancies through extended persistence in bone, Environmental Sciences Europe. Available at: https://enveurope.springeropen.com/articles/10.1186/s12302-025-01057-1.]
• Prenatal residential proximity to endocrine disrupting agricultural pesticides and menstrual cycle characteristics among Latina adolescents in California
  Adolescents’ menstrual cycle characteristics can be ‘vital signs’ of health and impact quality of life. While endocrine disrupting pesticides are commonly used in agriculture, limited research exists on how exposure might affect the adolescent menstrual cycle. We examined the association between prenatal residential proximity to 11 agricultural pesticides and menstrual cycle characteristics at 16 years of age among 273 Latina adolescents from the Center for the Health Assessment of Mothers and Children of Salinas (CHAMACOS) study. We estimated prenatal pesticide exposure by linking maternal residential addresses to California’s Pesticide Use Reporting database. Menstrual characteristics, including cycle length irregularities, painful menstruation, and heavy bleeding, were evaluated through questionnaire. We used generalized linear models to evaluate exposure-outcome associations one pesticide at a time. To adjust for co-exposure to pesticides, we used Bayesian Hierarchical Models to include all pesticide exposures in one model. In our single exposure model, we observed increased odds of heavy bleeding (OR: 1.29, 95% CI: 1.01, 1.64) for each doubling in prenatal methomyl exposure. This association persisted in our joint exposure model (OR: 1.09, CrI: 0.99, 1.19). Our results suggest prenatal exposure to endocrine disrupting pesticides may impact certain adolescent menstrual cycle characteristics.
  [Paul, J. et al. (2025) Prenatal residential proximity to endocrine disrupting agricultural pesticides and menstrual cycle characteristics among Latina adolescents in California, American Journal of Epidemiology. Available at: https://academic.oup.com/aje/advance-article/doi/10.1093/aje/kwaf059/8083004.]
• Re-Evaluating the Use of Glyphosate-based Herbicides: Implications on Fertility
  Glyphosate-based herbicides (GBHs) are the most widely used herbicides in the United States, accounting for 19% of estimated global use. Although the Environmental Protection Agency (EPA) has reaffirmed that the active ingredient glyphosate (GLY) is safe for humans, recent studies on exposure have suggested association with cancer, metabolic disorders, endocrine disruption and infertility, Alzheimer's and Parkinson's disease, and psychological disorders. Current literature on the effects of GLY exposure on reproductive function suggests potential clinical implications on women's reproductive health, including polycystic ovarian syndrome (PCOS), endometriosis, infertility, and adverse pregnancy outcomes. The continued debate surrounding GLY exposure increasingly exemplifies the public health issue surrounding its consequences on female reproductive health, human fertility, and the potential epigenetic effects. In this review, we discuss the potential mechanisms of toxicity and endocrine disruption of GLY on the female reproductive tract and highlight possible implications of GLY exposure on reproductive health outcomes. GLY adversely affects the female reproductive system through increased oxidative stress, endocrine disruption of reproductive hormones, histological changes in ovarian and uterus tissue, and diminished ovarian function in human cell lines and animals. We conclude that increased research efforts are warranted regarding the safety and efficacy of GBH as it pertains to female reproduction, as well as investments in cost-effective alternatives with the potential to reduce GBH usage.
  [Stone, A. et al. (2025) Re-Evaluating the Use of Glyphosate-based Herbicides: Implications on Fertility, Reproductive Sciences. Available at: https://link.springer.com/article/10.1007/s43032-025-01834-6.]
• The combination of microplastics and glyphosate affects the microbiome of soil inhabitant Enchytraeus crypticus
  Microplastics and pesticides are emerging contaminants that threaten soil ecosystems, yet their combined effects on soil health and soil fauna remain poorly understood. In this study, we constructed a microcosm to assess the individual and combined effects of microplastics and glyphosate on soil physicochemical properties, microbial communities, and the gut microbiome of soil invertebrates (Enchytraeus crypticus). Biodegradable polylactic acid (PLA) and conventional polyethylene terephthalate (PET) were introduced at environmentally relevant concentrations. Our results revealed that PLA had a stronger disruptive effect on soil microbial communities than PET, altering microbial diversity and functional composition. Glyphosate, in contrast, primarily influenced the gut microbiome of E. crypticus, reducing microbial diversity and inducing oxidative stress. Combined exposure to microplastics and glyphosate significantly intensified oxidative stress but did not amplify microbial dysbiosis beyond the effects of microplastics alone. Compare to PET, PLA combined with glyphosate had the most pronounced effects on both soil and gut microbiomes, suggesting that biodegradable microplastics may pose greater ecological risks than conventional microplastics when used alongside pesticides. These findings underscore the need for a reassessment of biodegradable plastic use in agriculture and highlight the complex interactions between microplastics and pesticides in shaping soil ecosystem health.
  [Yang, Huihui & Zheng, Guogang & Qin, Guoyan & Zhang, Qi & Zhang, Ziyao & Chen, Bingfeng & Lei, Chaotang & Liu, Meng & Cui, Rui & Sun, Liwei & Xia, Shengjie & Peijnenburg, Willie & Lu 陆涛, Tao & Tang, Tao & Qian, Haifeng. (2025). The combination of microplastics and glyphosate affects the microbiome of soil inhabitant Enchytraeus crypticus. Journal of hazardous materials. 489. 137676. 10.1016/j.jhazmat.2025.137676. ]
• The induced hepatotoxicity and genotoxicity in Oreochromis niloticus exposed to a newly released florpyrauxifen-benzyl herbicide
  The investigation of the toxic potential of a newly introduced herbicide, Florpyrauxifen-benzyl (FPX), on Nile tilapia (Oreochromis niloticus) was the aim of this study. For 96 h, the median lethal concentration (LC50) was assessed in fish juveniles using the Probit analysis following the exposure to five concentrations of FPX (2–3 ppm). For investigating some mechanisms of FPX toxicity, fish were allocated into three groups (0, 0.27 and 0.54 ppm of FPX) and the cut-off intervals of the exposure were at 7 and 15 days. Liver malondialdehyde (MDA) and reduced glutathione (GSH) levels were assessed. In addition, superoxide dismutase (SOD) and catalase (CAT) were evaluated at both of transcriptional and enzymatic activity levels. Histopathological effects on the liver and erythrocytic nuclear abnormalities (ENAs) were monitored too. The 96h-LC50 was found to be 2.61 ppm, revealing the toxic potential of the FPX on Nile tilapia. Concentrations of FPX induced oxidative stress in fish by altering activities of antioxidant enzymes and their transcripts. The genotoxic effect of FPX was evidenced by a significant (P < 0.05) increase in micronuclei (MNs) and ENA frequencies. Significant liver histopathological alterations were observed at both FPX concentrations, with the highest effects at a concentration of 0.54 ppm FPX. Results suggest that FPX may exert oxidative, genotoxic, and histopathological effects on non-targeted species such as Nile tilapia if it is used improperly. Although fish could be used as an indicator for toxic materials in the aquatic habitat, future studies on other organisms, FPX concentrations or durations are recommended.
  [Nabet, N. et al. (2025) The induced hepatotoxicity and genotoxicity in Oreochromis niloticus exposed to a newly released florpyrauxifen-benzyl herbicide, Ecotoxicology. Available at: https://link.springer.com/article/10.1007/s10646-025-02864-1.]
• Unraveling the toxic link between pesticides and brain cancer: a review on molecular mechanisms, signaling pathways and future research trends
  The widespread incidence of brain tumors presents a substantial obstacle to public health due to their debilitating and lethal outcomes. Although the etiology of brain tumors is still an enigma, emerging evidence indicates a strong correlation between pesticide exposure and the onset of brain cancer. The commonly used pesticides, including organophosphates, organochlorines and pyrethroids, exert their toxic effects by inducing oxidative stress that causes damage to nucleic acids, lipids, and proteins. Oxidative stress is a significant factor in the development of brain cancer mainly due to its elevated oxygen consumption and abundance of polyunsaturated fatty acids that make it more susceptible to oxidative harm. Pesticides induce oxidative stress through various pathways, such as JAK-STAT and Keap1/Nrf2/ARE, which regulate reactive oxygen species production and antioxidant responses. Despite extensive research linking pesticides to brain tumors, precise molecular mechanisms remain unclear. The present review attempts to discuss the molecular mechanisms by which pesticides induce oxidative stress and explores the interplay between various signaling pathways in regulating reactive oxygen species and reactive nitrogen species. It also highlights the complicated relationship between pesticide-induced oxidative stress and brain cancer development and emphasizes the need for further investigation into the genetic and epigenetic impacts of pesticides on xenobiotic detoxification systems and the production of oncometabolites. By providing a comprehensive overview of the molecular foundations of pesticide-mediated genetic damage, this paper aims to contribute significantly to the existing literature for developing regulatory measures and safer alternatives to mitigate the health risks associated with pesticide exposure.
  [Ahmad, M.B., Islam, A.U., Hassan, S. et al. Unraveling the toxic link between pesticides and brain cancer: a review on molecular mechanisms, signaling pathways and future research trends. Nucleus (2025). https://doi.org/10.1007/s13237-024-00529-8]
• Chlorpyrifos induces cytotoxicity via oxidative stress and mitochondrial dysfunction in HepG2 cells
  Chlorpyrifos (CPF), a widely used broad-spectrum organophosphate pesticide, has been associated with various adverse health effects in animals and humans. While its primary mechanism of action involves the irreversible inhibition of acetylcholinesterase, secondary mechanisms have also been suggested. The aim of the present study was to explore the secondary mechanisms of action involved in CPF-induced acute cytotoxicity using human hepatocarcinoma HepG2 cells. In particular, we investigated oxidative stress and mitochondrial function by assessing reactive oxygen species (ROS) generation, lipid peroxidation (LPO) and mitochondrial membrane potential (ΔΨm) alteration. Results showed that 24-h exposure to CPF (78.125-2500 μM) decreased cell viability in a concentration-dependent manner (IC50 = 280.87 ± 26.63 μM). Sub-toxic CPF concentrations (17.5, 35 and 70 μM) induced increases in ROS generation (by 83%), mitochondrial superoxide (by 7.1%), LPO (by 11%), and decreased ΔΨm (by 20%). CPF also upregulated Nrf2 protein expression, indicating the role of the latter in modulating the cellular response to oxidative insults. Overall, our findings suggest that CPF caused hepatotoxicity through oxidative stress and mitochondrial dysfunction. Given the re-emerging use of CPF, this study emphasizes the need for comprehensive analysis to elucidate its toxicity on non-target organs and associated mechanisms.
  [Montanarí, C., Franco-Campos, F., Taroncher, M., Rodríguez-Carrasco, Y., Zingales, V., & Ruiz, M. J. (2024). Chlorpyrifos induces cytotoxicity via oxidative stress and mitochondrial dysfunction in HepG2 cells. Food and chemical toxicology : an international journal published for the British Industrial Biological Research Association, 192, 114933. https://doi.org/10.1016/j.fct.2024.114933]
• Co-exposure to environmental microplastic and the pesticide 2,4-dichlorophenoxyacetic acid (2,4-D) induce distinctive alterations in the metabolome and microbial community structure in the gut of the earthworm Eisenia andrei
  Microplastics (MPs) are recognized as emergent pollutants and have become a significant environmental concern, especially when combined with other contaminants. In this study, earthworms, specifically Eisenia andrei, were exposed to MPs (at a concentration of 10 μg kg−1 of soil), herbicide 2,4-D (7 mg kg−1 of soil), and a combination of the two for 7 and 14 days. The chemical uptake in the earthworms was measured, and the bacterial and archaeal diversities in both the soil and earthworm gut were analyzed, along with the metabolomic profiles. Additionally, data integration of the two omics approaches was performed to correlate changes in gut microbial diversity and the different metabolites. Our results demonstrated that earthworms ingested MPs and increased 2,4-D accumulation. More importantly, high-throughput sequencing revealed a shift in microbial diversity depending on single or mixture exposition. Metabolomic data demonstrated an important modulation of the metabolites related to oxidative stress, inflammatory system, amino acids synthesis, energy, and nucleic acids metabolism, being more affected in case of co-exposure. Our investigation revealed the potential risks of MPs and 2,4-D herbicide combined exposure to earthworms and soil fertility, thus broadening our understanding of MPs’ toxicity and impacts on terrestrial environments.
  [Boughattas, I., Vaccari, F., Zhang, L., Bandini, F., Miras-Moreno, B., Missawi, O., Hattab, S., Mkhinini, M., Lucini, L., Puglisi, E., & Banni, M. (2024). Co-exposure to environmental microplastic and the pesticide 2,4-dichlorophenoxyacetic acid (2,4-D) induce distinctive alterations in the metabolome and microbial community structure in the gut of the earthworm Eisenia andrei. Environmental pollution (Barking, Essex : 1987), 344, 123213. https://doi.org/10.1016/j.envpol.2023.123213]
• Effect of Mineral Fertilizers and Pesticides Application on Bacterial Community and Antibiotic-Resistance Genes Distribution in Agricultural Soils
  Soils are a hotspot for the emergence and spread of antibiotic resistance. The effects of agrochemical treatments on the bacterial community of agricultural soils and the content of antibiotic-resistance genes (ARGs) were studied. Treatments included the following: control, mineral fertilizers (NPKs), pesticides, and the combined treatment of soils under soya (Glycine max), sunflower (Helianthus annuus L.), and wheat (Triticum aestivum). Bacterial community taxonomic composition was studied using 16S rRNA gene sequencing. The content of 10 ARGs and 3 integron genes (intI1, intI2, intI3) was determined using quantitative real-time PCR. The results showed that the treatments had little effect on the taxonomic composition and diversity of the soil bacterial community. The most significant factors determining differences in the microbial community were sampling time and soil physico-chemical parameters. A significant role of the bacterial community in ARG distribution in soils was demonstrated. Representatives of the Pseudomonas, Bacillus, Sphingomonas, Arthrobacter genera, and the Nocardioidaceae and Micrococcaceae families were likely ARG hosts. The presence of integron genes of all three classes was detected, the most numerous being intI3. This work provides important information on the role of agricultural soils in ARG transfer, and the findings may be useful for sustainable and safe agricultural development.
  [Khmelevtsova, L. et al. (2024) Effect of mineral fertilizers and pesticides application on bacterial community and antibiotic-resistance genes distribution in agricultural soils, Agronomy. Available at: https://www.mdpi.com/2073-4395/14/5/1021]
• In vivo tebuconazole administration impairs heart electrical function and facilitates the occurrence of dobutamine-induced arrhythmias: involvement of reactive oxygen species
  Tebuconazole (TEB), a widely used pesticide in agriculture to combat fungal infections, is commonly detected in global food, potable water, groundwater, and human urine samples. Despite its known in vivo toxicity, its impact on heart function remains unclear. In a 28-day study on male Wistar rats (approximately 100 g), administering 10 mg/kg/day TEB or a vehicle (control) revealed no effect on body weight gain or heart weight, but an increase in the infarct area in TEB-treated animals. Notably, TEB induced time-dependent changes in in vivo electrocardiograms, particularly prolonging the QT interval after 28 days of administration. Isolated left ventricular cardiomyocytes exposed to TEB exhibited lengthened action potentials and reduced transient outward potassium current. TEB also increased reactive oxygen species (ROS) production in these cardiomyocytes, a phenomenon reversed by N-acetylcysteine (NAC). Furthermore, TEB-treated animals, when subjected to an in vivo dobutamine (Dob) and caffeine (Caf) challenge, displayed heightened susceptibility to severe arrhythmias, a phenotype prevented by NAC. In conclusion, TEB at the no observed adverse effect level (NOAEL) dose adversely affects heart electrical function, increases arrhythmic susceptibility, partially through ROS overproduction, and this phenotype is reversible by scavenging ROS with NAC.
  [Teixeira-Fonseca, J. L., Souza, D. S., Conceição, M. R. L., Marques, L. P., Durço, A. O., Silva, P. L. D., Joviano-Santos, J. V., Santos-Miranda, A., & Roman-Campos, D. (2024). In vivo tebuconazole administration impairs heart electrical function and facilitates the occurrence of dobutamine-induced arrhythmias: involvement of reactive oxygen species. Food and chemical toxicology : an international journal published for the British Industrial Biological Research Association, 187, 114596. https://doi.org/10.1016/j.fct.2024.114596]
• Meta-analytical review of antioxidant mechanisms responses in animals exposed to herbicide 2,4-D herbicide
  The 2,4-Dichlorophenoxyacetic acid (2,4-D) is a low-cost herbicide to eradicate broadleaf weeds. Since the development of 2,4-D resistant transgenic crops, it has been described as one of the most widely distributed pollutants in the world, increasing concern about its environmental impacts. This study aimed to elucidate the antioxidant system response in animals exposed to 2,4-D by different routes of exposure. It focused on determining if tissue, phylogenetic group, and herbicide formulation would influence the antioxidant mechanisms. A careful literature search of Scopus, WoS, and Science Direct retrieved 6983, 24,098, and 20,616 articles, respectively. The dataset comprised 390 control-treatment comparisons and included three routes of exposure: transgenerational, oral, and topical. The data set for transgenerational and oral exposure revealed oxidative stress through a decrease in enzymatic activities and the level of molecules of the antioxidant system. In contrast, topical exposure increased the oxidative stress. Tissue-specific analyses revealed that the transgenerational effects reduced hepatic catalase (CAT) activity. Oral exposure caused a variety of effects, including increased CAT activity in the prostate and decreased activity in various tissues. Mammals predominate in the transgenerational and oral groups, showing a significantly reduced activity of the antioxidant system. In contrast, in the topical exposure, an increased activity of oxidative stress biomarkers was observed in fish, earthworms, and mollusks. The effects of the 2,4-D formulation on oxidative stress responses showed significant differences between pure and commercial formulations, with oral exposure resulting in decreased activity and topical exposure increasing responses. In summary, orally exposed animals exhibited a clear decrease in enzyme activities, transgenerational exposure elicited tissue-specific prompted biochemical reductions, and topical exposure induced increased responses, emphasizing the need for unbiased exploration of the effects of 2,4-D on biomarkers of oxidative stress while addressing publication bias in oral and topical datasets.
  [da Silva, A. P., Poquioma Hernández, H. V., Comelli, C. L., Guillén Portugal, M. A., Moreira Delavy, F., de Souza, T. L., de Oliveira, E. C., de Oliveira-Ribeiro, C. A., Silva de Assis, H. C., & de Castilhos Ghisi, N. (2024). Meta-analytical review of antioxidant mechanisms responses in animals exposed to herbicide 2,4-D herbicide. The Science of the total environment, 924, 171680. https://doi.org/10.1016/j.scitotenv.2024.171680]
• Pesticide exposure and spontaneous abortion risk: A comprehensive systematic review and meta-analysis
  Backgrounds and aim
  Exposure to pesticides has been proposed as a potential contributor to adverse pregnancy outcomes, possibly through the induction of inflammation, oxidative stress, and disruption of endocrine functions. Nevertheless, the definitive link between prenatal pesticide exposure and the risk of Spontaneous Abortion (SAB) remains uncertain. The objective of this systematic review is to explore and analyze the existing evidence regarding the link between pesticide exposure and the risk of SAB.
  Methods
  A comprehensive systematic literature search was carried out on PubMed, Web of Science, and Scopus from their inception until February 2024 to identify relevant studies exploring the potential link between pesticide exposure and SAB. The frequency of SAB events and the total number of patients in each group were used to calculate the Relative Risk (RR) using the Mantel-Haenszel random-effects model. Heterogeneity among the studies was evaluated by visually inspecting the forest plot and performing the Chi-square test and I2 tests. We also used RevMan version 5.4 for Windows for the analysis. We also used the NIH tool to assess the quality of the included studies.
  Results
  The initial database search yielded 2121 results, with 1525 articles remaining after removing duplicates. After screening, 29 articles were eligible for full-text review, and 18 studies (Four case-control, eleven cohorts, three cross-sectional) were included in the meta-analysis, comprising 439,097 participants. All included studies evaluated the primary outcome, SAB. Most of the included studies were cross-sectional in design, and pesticide exposure was primarily assessed through questionnaires administered to patients. We found that most of our observational studies, precisely 12 out of the total, were deemed fair quality. Four studies were rated poor quality, while only two received a good quality rating. The analysis demonstrated a significant 41 % increase in SAB risk among pregnant women exposed to pesticides compared to pregnant women without exposure to pesticides (RR= 1.41, 95 % CI; [1.10, 1.80], P= 0.006).
  Conclusion
  Our systematic review and meta-analysis revealed a significant 41 % increase in the risk of SAB among pregnant women exposed to pesticides. However, it is essential to acknowledge the limitations of the current evidence: potential publication bias and the inability to establish causality. Moving forward, future research should focus on longitudinal studies, mechanistic insights, and risk reduction strategies. In summary, our findings underscore the urgency of public health measures to protect maternal and fetal health in pesticide-exposed areas. Rigorous research and preventive strategies are crucial to mitigate adverse outcomes.
  [Albadrani, M.S., Aljassim, M.T. and El-Tokhy, A.I. (2024) Pesticide exposure and spontaneous abortion risk: A comprehensive systematic review and meta-analysis, Ecotoxicology and Environmental Safety. Available at: https://www.sciencedirect.com/science/article/pii/S0147651324010765.]
• Pesticides, cancer, and oxidative stress: an application of machine learning to NHANES data
  

  Abstract

  Background

  The large-scale application of pyrethroids and organophosphorus pesticides has great benefits for pest control. However, the increase of cancer incidence rate in recent years has also caused public concern about the health risks of pesticides. Hence, we utilized data from the National Health and Nutrition Examination Survey (NHANES) to assess the association and risk between pesticide exposure and several cancers, along with the comprehensive impact of oxidative stress. In this study, six cancers and six common pesticides were included to analyze their correlation and risk. And the levels of eight oxidative stress marks and two inflammatory markers were used for stratified analysis. Multiple logistic regression analysis was applied to estimate the odds ratio and 95% confidence intervals. Machine learning prediction models were established to evaluate the importance of different exposure factors.

  Results

  According to the data analyzed, each pesticide increased the risk of three to four out of six cancers on average. Iron, aspartate aminotransferase (AST), and gamma glutamyl transferase levels positively correlated with cancer risk in most cases of pesticide exposure. Except for demographic factors, factors such as AST, iron, and 3-phenoxybenzoic acid showed high contributions to the random forest model, which was consistent with our expectations. The receiver operating characteristic curve showed that the prediction model had sufficient accuracy (74.2%).

  Conclusion

  Our results indicated that specific pesticide exposure increased the risk of cancer, which may be mediated by various oxidative stress mechanisms. Additionally, some biochemical indicators have the potential to be screened for cancer prevention.

  
  [Liu, Y. et al. (2024) ‘Pesticides, cancer, and oxidative stress: An application of machine learning to Nhanes Data’, Environmental Sciences Europe, 36(1). doi:10.1186/s12302-023-00834-0. ]
• Physiological responses of oxidative damage, genotoxicity and hematological parameters of the toxic effect of neonicotinoid-thiamethoxam in Oreochromis niloticus
  The purpose of investigation assessed the impacts of neonicotinoid thiamethoxam (TMX) at sublethal concentrations in hematological profile and renal function of Oreochromis niloticus. In the experiment, fish were exposed to TMX in four groups (0, 50, 100 and 150 ppm) for 7 days. At the end of the experiment, biochemical analysis of blood samples showed that the parameters indicating renal function showed a significant increase in serum enzymes ALT, AST, ALP and metabolites (BUN, urea, uric acid, creatinine and cortisol) concentrations, while albumin concentration decreased in a dose-dependent manner compared to the control group. In parallel with the decrease in Na+, K+ and Ca+2 in blood ion levels, there was a significant decrease in the activity of Na+/K+ ATPase, Ca+2 ATPase and AChE enzyme, levels of GSH and HSP70 in kidney tissue in TMX groups compared to the control group. It was determined that the toxic effect of TMX caused a significant increase in TBARS, PC, 8-OHdG levels, respectively. In conclusion, our study shows that TMX causes dose-dependent toxic effects, with knock-on effects on physiological processes regarding the hematological profile and renal function of O. niloticus.
  [Temiz, Ö., & Kargın, D. (2024). Physiological responses of oxidative damage, genotoxicity and hematological parameters of the toxic effect of neonicotinoid-thiamethoxam in Oreochromis niloticus. Environmental toxicology and pharmacology, 106, 104377. https://doi.org/10.1016/j.etap.2024.104377]
• Short-term immunotoxicity induced by florpyrauxifen-benzyl herbicide exposure in the spleen of male albino mice
  Florpyrauxifen-benzyl (FPB) is a new arylpicolinate systemic herbicide that has been used to control or suppress the majority of herbicide-resistant biotype weeds in rice. To our knowledge, the impact of FPB on the immune system remains undetected thus far. Hence, this work aimed to address the toxic effects of FPB and the possible related mechanisms on the spleen of exposed mice. Initially, an acute toxicological test was performed to ascertain the median lethal dose (LD50) of FPB for 24 h which was found to be 371.54 mg/kg b.wt. For mechanistic evaluation of FPB toxicity, three sublethal doses (1/20th, 1/10th, and 1/5th LD50) were orally administered to mice for 21 consecutive days. Changes in spleen relative weight, oxidative status, apoptotic and inflammatory markers, histopathological alterations were evaluated. Following the FPB exposure, significant (p < 0.05) decline in spleen index, apoptotic features, histolopathological changes were observed. Additionally, excessive oxidative stress in spleen tissues was monitored by downregulating antioxidant enzymes and upregulating the oxidant parameters. Furthermore, exposure to FPB resulted in notable activation of the NF-қB signaling pathway, accompanied by elevated levels of pro-inflammatory cytokines (namely, IL-1β and TNF-α) as well as CD3 and CD19 levels have decreased significantly in spleen tissues. Collectively, FPB exposure exhibited apoptosis, oxidative stress, immunosuppression, and inflammatory response in a dose-dependent manner, leading to spleen tissue damage and immunotoxicity. Further studies on FPB is recommended to outstand its hazards on ecosystems.
  [Morsi, D. S., Abu Quora, H. A., AboShabaan, H. S., El-Garawani, I. M., Abdel Moneim, A. E., & Hathout, H. M. R. (2024). Short-term immunotoxicity induced by florpyrauxifen-benzyl herbicide exposure in the spleen of male albino mice. Journal of experimental zoology. Part A, Ecological and integrative physiology, 341(6), 658–671. https://doi.org/10.1002/jez.2814]
• Tannic acid inhibits pain mediators, inflammation and oxidative stress in mice exposed to glyphosate-based herbicide
  Chronic exposure to glyphosate-based herbicide (Gly) has been associated with neurological disorders. Tannic acid (TA) is an antioxidant with attenuating action against neuroinflammation-associated conditions. This study evaluated the effect of Gly on pain perception alongside antinociceptive and anti-inflammatory actions of TA in Gly-exposed mice. Male Swiss mice were randomly divided into six groups (n=8): control (distilled water 0.2 ml/kg), Gly (Gly 500 mg/kg), Pre-TA + Gly (TA 50 mg/kg pre-treatment, afterwards Gly-administered), TA + Gly (TA 50 mg/kg and Gly co-administered), Pre-AA + Gly (ascorbic acid (AA) 10 mg/kg pre-treatment, afterwards Gly-administered), and AA + Gly (AA 10 mg/kg and Gly co-administered). Mechanical, thermal, and chemical pain were evaluated six weeks post vehicle/drugs administrations orally, followed by brain biochemical measurements. TA treatment alleviated Gly-induced hyperalgesia in similar version to the values of control and AA groups by increasing significantly (p < 0.05) nociceptive thresholds. Moreover, TA-treatment significantly decreased malondialdehyde (MDA) and pro-inflammatory cytokines (TNF-α, IL-1β, and IL-6) levels, significantly increased anti-inflammatory cytokines (IL-10, IL-4, and TGF-1β) levels, and antioxidant enzymes, catalase (CAT), glutathione peroxidase (GPx), and superoxide dismutase (SOD) activities compared to Gly-treated mice (p < 0.05). Conclusively, TA treatment exerted antinociceptive and anti-inflammatory actions, possibly through its antioxidant and anti-inflammatory actions in Gly-exposed mice. Notably, TA pre-treatment showed a better response than TA and Gly co-administration. We propose the potential neuroprotective and ameliorative functions of TA in Gly-induced hyperalgesia. This merits further clinical research into protective roles of TA against pesticide-related conditions.
  [Abolarin, P.O. and Owoyele, B.V. (2024) Tannic acid inhibits pain mediators, inflammation and oxidative stress in mice exposed to glyphosate-based herbicide, Environmental Analysis Health and Toxicology. Available at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11294660/. ]
• Tebuconazole Induces Mouse Fetal Testes Damage via ROS Generation in an Organ Culture Method
  The fungicide tebuconazole (TEB) poses risks to human and animal health via various exposure routes. It induces toxicity in multiple organs and disrupts reproductive health by affecting steroid hormone synthesis and fetal development. In this study, we investigated the impact of TEB on fetal testes using in vitro models, focusing on germ, Sertoli, and Leydig cells, and explored the mechanisms underlying cellular damage. The results revealed significant damage to germ cells and disruption of Leydig cell development. TEB exposure led to a decrease in germ cell numbers, as indicated by histological and immunostaining analyses. TEB induced the up- and down-regulation of the expression of fetal and adult Leydig cell markers, respectively. Additionally, TEB-treated fetal testes exhibited increased expression of oxidative-stress-related genes and proteins. However, co-treatment with the antioxidant N-acetylcysteine mitigated TEB-induced germ cell damage and prevented abnormal Leydig cell development. These findings suggest that administration of antioxidants can prevent the intratesticular damage typically caused by TEB exposure.
  [Lee, W. Y., Lee, R., & Park, H. J. (2024). Tebuconazole Induces Mouse Fetal Testes Damage via ROS Generation in an Organ Culture Method. International journal of molecular sciences, 25(13), 7050. https://doi.org/10.3390/ijms25137050]
• The Fungicide Ipconazole Can Activate Mediators of Cellular Damage in Rat Brain Regions
  This study aimed to investigate the toxicity of the fungicide ipconazole on oxidative status, cell death and inflammasome complex activation in the hypothalamus, cerebral cortex, striatum and hippocampus of rats. Female albino rats were randomly divided into a control group and four groups treated with ipconazole at doses of 1, 5, 10 and 20 mg/kg b.w., administered for six days. Ipconazole significantly increased MDA and ROS levels in all brain regions studied, while reducing catalase enzyme activity. The molecular expression of cell death-related genes (AKT1, APAF1, BNIP3, CASP3 and BAX) and the inflammasome complex (CASP1, IL1β, IL6, NLRP3, NFĸB and TNFα) was also assessed, showing increased expression in at least one brain region. The findings demonstrate that ipconazole induces central nervous system toxicity in mammals, highlighting its potential role as a risk factor in the development of neurodegenerative disorders in individuals exposed to this contaminant.
  [Villaorduña, C., Barrios-Arpi, L., Lira-Mejía, B., Ramos-Gonzalez, M., Ramos-Coaguila, O., Inostroza-Ruiz, L., Romero, A., & Rodríguez, J.-L. (2024). The Fungicide Ipconazole Can Activate Mediators of Cellular Damage in Rat Brain Regions. Toxics, 12(9), 638. https://doi.org/10.3390/toxics12090638]
• Thyroid under Attack: The Adverse Impact of Plasticizers, Pesticides, and PFASs on Thyroid Function
  Endocrine-disrupting chemicals (EDCs) are synthetic or natural compounds that interfere with the endocrine system, inducing harmful effects on organisms depending on the dose and period of exposure. Numerous studies have identified concerning amounts of EDCs in environmental and human samples. The thyroid gland is essential for thyroid hormone production and controls several body functions. Several EDCs have been classified as thyroid disruptors, impairing thyroid hormone production, synthesis, metabolism, transport, and/or actions. Notably, thyroid disorders are the second most prevalent endocrine disease worldwide, with incidence increasing significantly in recent years. Some studies have correlated this rise in thyroid dysfunctions and cancers with increased exposure to EDCs. Although many EDCs are linked to thyroid dysfunction, this review focuses on the deleterious effects of plasticizers, organochlorine pesticides, and per- and poly-fluoroalkyl substances on thyroid function. These contaminants are commonly found in food, water, and everyday products. Although the impact of human exposure to these EDCs is controversial, numerous epidemiological, in vivo, and in vitro studies have indicated their harmful effects on thyroid function. Given the critical role of thyroid function and hormone production in growth, metabolism, and development, this review summarizes the consequences of exposure to thyroid disruptors for human health.
  [Rodrigues, V.G. et al. (2024) Thyroid under Attack: The Adverse Impact of Plasticizers, Pesticides, and PFASs on Thyroid Function, Endocrines. Available at: https://www.mdpi.com/2673-396X/5/3/32.]
• Toxicological assessment of bromoxynil and 2-methyl-4-chlorophenoxyacetic acid herbicide in combination on Cirrhinus mrigala using multiple biomarker approach
  The widespread application of herbicides raises concerns about their impact on non-target aquatic organisms. This study aimed to evaluate the toxicity of a commercially available herbicide formulation containing Bromoxynil+MCPA (2-Methyl-4-chlorophenoxyacetic acid) on Cirrhinus mrigala (economically significant fish). A total of 210 juvenile fish were subjected to a triplicate experimental setup, with 70 fish allocated to each replicate, exposed to seven different concentrations of herbicide: 0 mg/L, 0.133 mg/L, 0.266 mg/L, 0.4 mg/L, 0.5 mg/L, 0.66 mg/L, and 0.8 mg/L, respectively, for a duration of 96 h. The median lethal concentration (LC50) was determined to be 0.4 mg/L. Significant hematological alterations were observed, including decreases in RBC counts, hemoglobin, hematocrit, and lymphocyte counts, along with an increase in erythrocyte indices. Biochemical analysis revealed elevated levels of neutrophils, WBCs, bilirubin, urea, creatinine, ALT, AST, ALP, and glucose in treated groups. Morphological abnormalities in erythrocytes and histopathological changes in gills, liver, and kidneys were noted. Pathological alterations in gills, liver and kidneys including epithelial cell uplifting, lamellar fusion, hepatolysis, and renal tubule degeneration were observed. Oxidative stress biomarkers such as TBARS (Thiobarbituric Acid Reactive Substance), ROS (Reactive Oxygen Species), and POD (Peroxides) activity increased, while antioxidant enzymatic activities decreased as toxicant doses increased from low to high concentrations. The study reveals that Bromoxynil+MCPA significantly disrupts physiological and hematobiochemical parameters in Cirrhinus mrigala, which highlights the substantial aquatic risks. In conclusion, the herbicide formulation induced significant alterations in various fish biomarkers, emphasizing their pivotal role in assessing the environmental impact of toxicity. This multi-biomarker approach offers valuable insights regarding the toxicological effects, thereby contributing substantially to the comprehensive evaluation of environmental hazards.
  [Afzal, F., Ghaffar, A., Jamil, H., Abbas, G., Tahir, R., & Ataya, F. S. (2024). Toxicological assessment of bromoxynil and 2-methyl-4-chlorophenoxyacetic acid herbicide in combination on Cirrhinus mrigala using multiple biomarker approach. The Science of the total environment, 926, 172019. https://doi.org/10.1016/j.scitotenv.2024.172019]
• Atrazine: cytotoxicity, oxidative stress, apoptosis, testicular effects and chemopreventive Interventions.
  Atrazine (ATZ) is an environmental pollutant that interferes with several aspects of mammalian cellular processes including germ cell development, immunological, reproductive and neurological functions. At the level of human exposure, ATZ reduces sperm count and contribute to infertility in men. ATZ also induces morphological changes similar to apoptosis and initiates mitochondria-dependent cell death in several experimental models. When in vitro experimental models are exposed to ATZ, they are faced with increased levels of reactive oxygen species (ROS), cytotoxicity and decreased growth rate at dosages that may vary with cell types. This results in differing cytotoxic responses that are influenced by the nature of target cells, assay types and concentrations of ATZ. However, oxidative stress could play salient role in the observed cellular and genetic toxicity and apoptosis-like effects which could be abrogated by antioxidant vitamins and flavonoids, including vitamin E, quercetin, kolaviron, myricetin and bioactive extractives with antioxidant effects. This review focuses on the differential responses of cell types to ATZ toxicity, testicular effects of ATZ in both in vitro and in vivo models and chemopreventive strategies, so as to highlight the current state of the art on the toxicological outcomes of ATZ exposure in several experimental model systems.
  [Abarikwu, S.O., Ezim, O.E., Ikeji, C.N. and Farombi, E.O., Atrazine: Cytotoxicity, Frontiers in Toxicology, 5, p.1246708.]
• Detrimental consequences of tebuconazole on redox homeostasis and fatty acid profile of honeybee brain
  Excessive use of azole fungicides in agriculture poses a potential threat to honeybees and other pollinator insects; however, the detailed effects of these molecules remain largely unclear. Hence, in the present study it was aimed to investigate the acute sublethal effects of tebuconazole on the redox homeostasis and fatty acid composition in the brain of honeybees. Our findings demonstrate that tebuconazole decreased total antioxidant capacity, the ratio of reduced to oxidized glutathione and disturbed the function of key antioxidant defense enzymes along with the induction of lipid peroxidation indicated by increased malondialdehyde levels, while it also altered the fatty acid profile of the brain. The present study highlights the negative impact of tebuconazole on honeybees and contributes to the understanding of potential consequences related to azole exposure on pollinator insects' health, such as the occurrence of colony collapse disorder.
  [Mackei, M., Sebők, C., Vöröházi, J., Tráj, P., Mackei, F., Oláh, B., Fébel, H., Neogrády, Z. and Mátis, G., 2023. Insect Biochemistry and Molecular Biology, 159, p.103990.]
• Effects of pesticide exposure on oxidative stress and DNA methylation urinary biomarkers in Czech adults and children from the CELSPAC-specimen cohort
  Current-use pesticide (CUP) exposure occurs mainly through diet and environmental application in both agricultural and urban settings. While pesticide exposure has been associated with many adverse health outcomes, the intermediary molecular mechanisms are still not completely elucidated. Among others, their roles in epigenetics (DNA methylation) and DNA damage due to oxidative stress are presumed. Scientific evidence on urinary biomarkers of such body response in general population is limited, especially in children.

  A total of 440 urine samples (n = 110 parent-child pairs) were collected during the winter and summer seasons in order to describe levels of overall DNA methylation (5-mC, 5-mdC, 5-hmdC, 7-mG, 3-mA) and oxidative stress (8-OHdG) biomarkers and investigate their possible associations with metabolites of pyrethroids (3-PBA, t/c-DCCA), chlorpyrifos (TCPY), and tebuconazole (TEB-OH). Linear mixed-effects models accounting for intraindividual and intrahousehold correlations were utilized. We applied false discovery rate procedure to account for multiplicity and adjusted for potential confounding variables.

  Higher urinary levels of most biological response biomarkers were measured in winter samples. In adjusted repeated measures models, interquartile range (IQR) increases in pyrethroid metabolites were associated with higher oxidative stress. t/c-DCCA and TCPY were associated with higher urinary levels of cytosine methylation biomarkers (5-mC and/or 5-mdC). The most robust association was observed for tebuconazole metabolite with 3-mA (−15.1% change per IQR increase, 95% CI = −23.6, −5.69) suggesting a role of this pesticide in reduced demethylation processes through possible DNA glycosylase inhibition.

  Our results indicate an urgent need to extend the range of analyzed environmental chemicals such as azole pesticides (e.g. prothioconazole) in human biomonitoring studies. This is the first study to report urinary DNA methylation biomarkers in children and associations between CUP metabolites and a comprehensive set of biomarkers including methylated and oxidized DNA alterations. Observed associations warrant further large-scale research of these biomarkers and environmental pollutants including CUPs.
  [Janoš, T. et al. (2023) Effects of pesticide exposure on oxidative stress and DNA methylation urinary biomarkers in Czech adults and children from the CELSPAC-specimen cohort, Environmental Research. Available at: https://www.sciencedirect.com/science/article/pii/S0013935123001603?via%3Dihub. ]

• Glyphosate exposure and urinary oxidative stress biomarkers in the Agricultural Health Study
  Background
  Glyphosate is the most widely applied herbicide worldwide, and its use has been associated with increased risks of certain hematopoietic cancers in epidemiologic studies. Animal and in vitro experiments suggest that glyphosate may induce oxidative stress, a key characteristic of carcinogens; however, evidence in human populations remains scarce. We investigated associations between glyphosate exposure and urinary oxidative stress biomarkers in the Biomarkers of Exposure and Effect in Agriculture study, a molecular epidemiologic subcohort in the Agricultural Health Study.

  Methods
  This analysis included 268 male farmers selected based on self-reported recent and lifetime occupational glyphosate use and 100 age- and geography-matched male nonfarmers. Concentrations of glyphosate and oxidative stress biomarkers (8-hydroxy-2′-deoxyguanosine [8-OHdG], 8-iso-prostaglandin-F2α, and malondialdehyde [MDA]) were quantified in first-morning-void urine. We performed multivariable linear regression to evaluate associations of urinary glyphosate and self-reported glyphosate use with each oxidative stress biomarker.

  Results
  Urinary glyphosate concentrations were positively associated with levels of 8-OHdG (highest vs lowest glyphosate quartile; geometric mean ratio = 1.15, 95% confidence interval = 1.03 to 1.28; Ptrend = .02) and MDA (geometric mean ratio = 1.20, 95% confidence interval = 1.03 to 1.40; Ptrend = .06) overall. Among farmers reporting recent glyphosate use (last 7 days), use in the previous day was also associated with statistically significantly increased 8-OHdG and MDA levels. Compared with nonfarmers, we observed elevated 8-iso-prostaglandin-F2α levels among farmers with recent, high past 12-month, or high lifetime glyphosate use.

  Conclusions
  Our findings contribute to the weight of evidence supporting an association between glyphosate exposure and oxidative stress in humans and may inform evaluations of the carcinogenic potential of this herbicide.
  [Vicky C Chang, Gabriella Andreotti, Maria Ospina, Christine G Parks, Danping Liu, Joseph J Shearer, Nathaniel Rothman, Debra T Silverman, Dale P Sandler, Antonia M Calafat, Laura E Beane Freeman, Jonathan N Hofmann, Glyphosate exposure and urinary oxidative stress biomarkers in the Agricultural Health Study, JNCI: Journal of the National Cancer Institute, Volume 115, Issue 4, April 2023, Pages 394–404, https://doi.org/10.1093/jnci/djac242]

• Glyphosate-induced liver and kidney dysfunction, oxidative stress, immunosuppression in Nile tilapia, but ginger showed a protection role
  The water-borne herbicides are involved in the toxicity of aquatic animals resulting in impaired health status and low productivity. Dietary medicinal herbs present a practical solution to relieve the impacts of herbicides toxicity on the performances of aquatic animals. Herein, we investigated the toxicity of commercial glyphosate-induced oxidative stress, immunosuppression, liver and kidney dysfunction, and the protective role of ginger or ginger nanoparticles in Nile tilapia. Fish were allocated into four groups: the first group presented the control without glyphosate toxicity and ginger feeding, the second group intoxicated with glyphosate at 0.6 mg/L and fed ginger free diet, the third group intoxicated with glyphosate and fed ginger at 2.5 g/kg, and the fourth group intoxicated with glyphosate and fed ginger nanoparticles at 2.5 g/kg. Fish were kept under the experimental conditions for four weeks, and the samples of blood and tissues were collected after 2 and 4 weeks. Markedly, fish exposed to glyphosate showed the highest ALT and AST activities, glucose and cortisol levels, and malondialdehyde levels (MDA) in gills and tissues. While fish in the control and fish intoxicated with glyphosate and fed ginger nanoparticles had the lowest ALT and AST activities, glucose and cortisol levels, and MDA levels after 2 and 4 weeks (P < 0.05). Fish fed dietary ginger had lower ALT and AST activities, glucose and cortisol levels, and MDA levels than the glyphosate intoxicated group after 2 and 4 weeks (P < 0.05). Interestingly, fish-fed ginger nanoparticles showed lower urea and creatinine levels and higher total protein, albumin, and globulin than the glyphosate intoxicated group (P < 0.05) and similar to the control (P > 0.05). Further, fish intoxicated with glyphosate and fed ginger nanoparticles had the highest GSH, lysozyme activity, and immunoglobulin levels after 2 and 4 weeks (P < 0.05). In conclusion, ginger nanoparticles are superior to the standard ginger form in enhancing the antioxidative and immune responses of Nile tilapia exposed to glyphosate.
  [Abdelmagid, A.D., Said, A.M., Abd El-Gawad, E.A. et al. Glyphosate-induced liver and kidney dysfunction, oxidative stress, immunosuppression in Nile tilapia, but ginger showed a protection role. Vet Res Commun 47, 445–455 (2023). https://doi.org/10.1007/s11259-022-09961-0]
• Individual and joint effects of glyphosate and cypermethrin formulations on two human cell lines
  The final effect of pesticides and their mixtures on living organisms is determined by the particular toxicodynamics of the system. Oxidative stress is one of the most studied molecular mechanisms of toxicity due to increasing evidence supporting its association with the toxic effects of different agrochemicals. In the present study we evaluated the presence of redox balance alterations in the cell lines HEp-2 and A549 exposed to formulations of glyphosate (March®) and cypermethrin (Superfina®) used separately or in combination (in a proportion equivalent to that used in soybean fields). We determined the activity of catalase, superoxide dismutase, glutathione S-transferase, intracellular GSH content, content of oxidized proteins (as measure of damage) and intracellular ROS content in both cell lines at two different mixture concentrations. Additionally, we evaluated the presence of statistical interaction to determine if the effect of the mixture on the parameters evaluated was additive, synergistic, or antagonistic. For this purpose, we used the Combination Subthresholding, Cooperative Effect and Statistical Linear Interaction approaches. We found that the interaction between pesticides depended on their concentration and the cellular models studied.
  [Coalova, I., March, H., de Molina, M.D.C.R. and Chaufan, G., 2023. Toxicology and Applied Pharmacology, 461, p.116398.]
• Ipconazole Induces Oxidative Stress, Cell Death, and Proinflammation in SH-SY5Y Cells
  Ipconazole is an antifungal agrochemical widely used in agriculture against seed diseases of rice, vegetables, and other crops; due to its easy accumulation in the environment, it poses a hazard to human, animal, and environmental health. Therefore, we investigated the cytotoxic effect of ipconazole on SH-SY5Y neuroblastoma cells using cell viability tests (MTT), ROS production, caspase3/7 activity, and molecular assays of the biomarkers of cell death (Bax, Casp3, APAF1, BNIP3, and Bcl2); inflammasome (NLRP3, Casp1, and IL1β); inflammation (NFκB, TNFα, and IL6); and antioxidants (NRF2, SOD, and GPx). SH-SY5Y cells were exposed to ipconazole (1, 5, 10, 20, 50, and 100 µM) for 24 h. The ipconazole, in a dose-dependent manner, reduced cell viability and produced an IC50 of 32.3 µM; it also produced an increase in ROS production and caspase3/7 enzyme activity in SH-SY5Y cells. In addition, ipconazole at 50 µM induced an overexpression of Bax, Casp3, APAF1, and BNIP3 (cell death genes); NLRP3, Casp1, and IL1B (inflammasome complex genes); and NFκB, TNFα, and IL6 (inflammation genes); it also reduced the expression of NRF2, SOD, and GPx (antioxidant genes). Our results show that ipconazole produces cytotoxic effects by reducing cell viability, generating oxidative stress, and inducing cell death in SH-SY5Y cells, so ipconazole exposure should be considered as a factor in the presentation of neurotoxicity or neurodegeneration.
  [Villaorduña, C., Mendoza-Carlos, M., Chuyma, M., Avilés, J., Avalos-Diaz, A., Lozano-Reategui, R., Garcia-Ruiz, J., Panduro-Tenazoa, N., Vargas, J., Moran-Quintanilla, Y., & Rodríguez, J. L. (2023). Ipconazole Induces Oxidative Stress, Cell Death, and Proinflammation in SH-SY5Y Cells. Toxics, 11(7), 566. https://doi.org/10.3390/toxics11070566]
• Maternal exposure to a glyphosate-based herbicide impairs placental development through endoplasmic reticulum stress in mice
  Glyphosate-based herbicides (GBHs) are the most widely used agrochemicals worldwide, increasing the risk of their occurrence in the environment. This study aimed to explore effects and mechanisms of GBH exposure on placental development in vivo during pregnancy in mice. Pregnant mice received GBH by gavage at 0, 5, and 50 mg⋅kg-1⋅day-1 doses from gestational day (GD) 1 to GD 13 and were sacrificed on GD 13 or GD19. Our data indicated that GBH administration significantly increased the number of resorbed fetuses, reduced the weight of fetuses and placentas, and inhibited placental growth, as evident from decreased placental total area and spongiotrophoblast area on GD 19. GBH treatment also inhibited proliferation and induced apoptosis of placenta via upregulation of Bax, cleaved caspase-3 and -12 expression, and downregulation of B cell lymphoma (Bcl)-2 expression. Further study showed that GBH exposure significantly increased expression levels of glucose-regulated protein 78 (GRP78), protein kinase RNA-like endoplasmic reticulum kinase (PERK), and C/EBP homologous protein (CHOP) mRNAs and proteins and triggered oxidative stress in placenta on GD 13 and GD 19. In conclusion, our findings suggest that maternal exposure to GBH can impair placental development through the endoplasmic reticulum stress-mediated activation of GRP78/PERK/CHOP signaling pathway in mice.
  [Liu, M., Lu, S., Yang, C., Zhang, D., Zhu, J., Yin, J., Zhao, H., Yang, B. and Kuang, H., 2023. Food and Chemical Toxicology, 173, p.113640.]
• Metabolic Consequences of the Water We Drink: A Study Based on Field Evidence and Animal Model Experimentation
  The effect of the chronic consumption of water contaminated with residual concentrations of DDT's metabolites (DDD-dichlorodiphenyldichloroethane and DDE-dichlorodiphenyldichloroethylene) found in the environment were evaluated on the biometric, hematological and antioxidant system parameters of the hepatic, muscular, renal and nervous tissues of Wistar rats. The results showed that the studied concentrations (0.002 mg.L-1 of DDD plus 0.005 mg.L-1 of DDE) could not cause significant changes in the hematological parameters. However, the tissues showed significant alteration in the activity of the antioxidant system represented by the increase in the activity of the enzymes gluthathione S-transferases in the liver, superoxide dismutase in the kidney, gluthathione peroxidase in the brain, and several changes in enzymatic activity in muscle (SOD, GPx and LPO). The enzymes alanine aminotransaminase (ALT) and aspartate aminotransaminase (AST) were also evaluated for the amino acids' metabolism in the liver, with ALT showing a significant increase in the exposed animals. In the integrative analysis of biomarkers (Permanova and PCOA), the studied concentrations showed possible metabolic changes and damage to cellular structures evidenced by increased oxidative stress and body weight gain among the treated animals. This study highlights the need for further studies on the impact of banned pesticides still present in soils that may induce adverse effects in organisms that may prevail in future generations and the environment.
  [Wolfart, J.C., Theodoro, J.L., Silva, F.C., de Oliveira, C.M.R., Ferreira, N.G. and Bittencourt Guimarães, A.T., 2023. Toxics, 11(4), p.315.]
• Micro(nano)plastics: A review on their interactions with pharmaceuticals and pesticides
  

  Abstract

  This review provides an overview of the current knowledge addressing the interactions between micro(nano)plastics (MNPs) and pharmaceuticals or pesticides, highlights the main findings, and outlines research perspectives for future investigations. The available studies demonstrated that MNPs can act as pollutant carriers. The reviewed literature reveals that MNPs influence the toxicity of pharmaceuticals and pesticides in various environmental compartments, modulating the toxicity of pharmaceuticals and pesticides, either through antagonistic or synergistic interactions. MNPs have been shown to mostly confer protective effects against the toxicity of antibiotics, while exacerbating the toxic effects of certain pesticides. To ensure a more comprehensive understanding of the interactions between MNPs and pharmaceuticals/pesticides, future research should focus on several key aspects that include more environmentally relevant scenarios (e.g., concentrations, long-term exposures), elucidation of the underlying mechanisms of action at molecular and cellular levels, addressing effects on different species and also considering climate change scenarios.

  
  [Barreto, M., Lopes, I. and Oliveira, M. (2023) ‘Micro(Nano)Plastics: A review on their interactions with pharmaceuticals and pesticides’, TrAC Trends in Analytical Chemistry, 169, p. 117307. doi:10.1016/j.trac.2023.117307. ]
• Neuroprotective effect of piracetam-loaded magnetic chitosan nanoparticles against thiacloprid-induced neurotoxicity in albino rats
  Thiacloprid (TH) is a neurotoxic agricultural insecticide and potential food contaminant. The purpose of this study was to investigate the relationship between TH exposure and memory dysfunction in rats, as well as the potential protective effect of piracetam and piracetam-loaded magnetic chitosan nanoparticles (PMC NPs). Rats were divided into five equal groups (six rats/group). The control group received saline. Group II was treated with PMC NPs at a dose level of 200 mg/kg body weight (Bwt); Group III was treated with 1/10 LD50 of TH (65 mg/kg Bwt); Group IV was treated with TH (65 mg/kg Bwt) and piracetam (200 mg/kg Bwt); Group V was co-treated with TH (65 mg/kg Bwt) and PMC NPs (200 mg/kg Bwt). All animal groups were dosed daily for 6 weeks by oral gavage. Footprint analysis, hanging wire test, open field test, and Y-maze test were employed to assess behavioral deficits. Animals were euthanized, and brain tissues were analyzed for oxidative stress biomarkers, proinflammatory cytokines, and gene expression levels of glial fibrillary acidic protein (GFAP), amyloid-beta precursor protein (APP), B-cell lymphoma 2 (Bcl-2), and caspase-3. Brain and sciatic nerve tissues were used for the evaluation of histopathological changes and immunohistochemical expression of tau protein and nuclear factor kappa B (NF-κB), respectively. The results revealed that TH-treated rats suffered from oxidative damage and inflammatory effect on the central and peripheral nerves. The administration of PMC NPs considerably protected against TH-induced neuronal damage, increased antioxidant enzyme activity, decreased inflammatory markers, and improved behavioral performance than the group treated with piracetam. The neuroprotective effect of PMC NPs was mediated through the inhibition of GFAP, APP, caspase-3, Tau, and NF-κB gene expression with induction of Bcl-2 expression. In conclusion, TH could induce oxidative stress, inflammatory and neurobehavior impairment in rats. However, PMC NPs administration markedly mitigated TH-induced brain toxicity, possibly via oxidative and inflammatory modulation rather than using piracetam alone.
  [Abomosallam, M., Hendam, B.M., Abdallah, A.A. et al. Neuroprotective effect of piracetam-loaded magnetic chitosan nanoparticles against thiacloprid-induced neurotoxicity in albino rats. Inflammopharmacol 31, 943–965 (2023). https://doi.org/10.1007/s10787-023-01151-x]
• Organochlorine pesticides, oxidative stress biomarkers, and leukemia: a case-control study
  Exposure to pesticides has been linked to an elevated risk of leukemia. The present research aimed to evaluate the relationship between organochlorine (OC) pesticides and biomarkers of oxidative stress in leukemia patients. This work was conducted on 109 patients with leukemia and 109 healthy controls. The serum concentrations of seven derivatives of OCs including alpha-HCH, beta-HCH, gamma-HCH, 2,4-DDT, 4,4-DDT, 2,4-DDE, and 4,4-DDE along with acetylcholinesterase (AChE), glutathione peroxidase (GPx), superoxide dismutase (SOD), paraoxonase-1 (PON1), and catalase (CAT) activities as well as total antioxidant capacity (TAC), nitric oxide (NO), protein carbonyl (PC), and malondialdehyde (MDA) levels were measured in all the subjects. Levels of OCs were remarkably higher in leukemia patients compared to the controls (p < 0.05). In addition, levels of SOD, AChE, GPx, PON-1, and TAC were remarkably lower in leukemia patients compared to controls (p < 0.05). In contrast, MDA, NO, and PC concentrations were higher in leukemia patients than in the controls (p < 0.05). Moreover, the serum level of 4,4-DDE was negatively associated with GPx activity (p = 0.038). Our findings suggest that OCs may play a role in the development of leukemia by disrupting the oxidant/antioxidant balance.
  [Rafeeinia, A., Asadikaram, G., Karimi Darabi, M., Abolhassani, M., Moazed, V. and Abbasi-Jorjandi, M., 2023. Journal of Investigative Medicine, 71(3), pp.295-306.]
• Oxidative Stress and Antioxidants in Neurodegenerative Disorders
  Neurodegenerative disorders constitute a substantial proportion of neurological diseases with significant public health importance. The pathophysiology of neurodegenerative diseases is characterized by a complex interplay of various general and disease-specific factors that lead to the end point of neuronal degeneration and loss, and the eventual clinical manifestations. Oxidative stress is the result of an imbalance between pro-oxidant species and antioxidant systems, characterized by an elevation in the levels of reactive oxygen and reactive nitrogen species, and a reduction in the levels of endogenous antioxidants. Recent studies have increasingly highlighted oxidative stress and associated mitochondrial dysfunction to be important players in the pathophysiologic processes involved in neurodegenerative conditions. In this article, we review the current knowledge of the general effects of oxidative stress on the central nervous system, the different specific routes by which oxidative stress influences the pathophysiologic processes involved in Alzheimer’s disease, Parkinson’s disease, Amyotrophic Lateral Sclerosis and Huntington’s disease, and how oxidative stress may be therapeutically reversed/mitigated in order to stall the pathological progression of these neurodegenerative disorders to bring about clinical benefits.
  [Olufunmilayo, E. O., Gerke-Duncan, M. B., & Holsinger, R. M. D. (2023). Oxidative Stress and Antioxidants in Neurodegenerative Disorders. Antioxidants, 12(2), 517. https://doi.org/10.3390/antiox12020517]
• Oxidative stress contributes to flumioxazin-induced cardiotoxicity in zebrafish embryos
  Flumioxazin is a widely applied herbicide for the control of broadleaf weeds, including aquatic plants. Current evidence suggests that flumioxazin could induce cardiac defects (ventricular septal defects) in vertebrates, but the underlining mechanisms remain unclear. Because of the inhibitory effect of flumioxazin on polyphenol oxidase, the assumption is made that flumioxazin-induced cardiotoxicity is caused by oxidative stress. To verify whether oxidative stress plays an important role in flumioxazin-induced cardiotoxicity, we compared the differences in heart phenotype, oxidative stress level, apoptosis, and gene expression between flumioxazin exposure and a normal environment, and we also tested whether cardiotoxicity could be rescued with astaxanthin. The results showed that flumioxazin induced both cardiac malformations and the abnormal gene expression associated with cardiac development. Cardiac malformations included pericardial edema, cardiac linearization, elongated heart, cardiomegaly, cardiac wall hypocellularity, myocardial cell atrophy with a granular appearance, and a significant gap between the myocardial intima and the adventitia. An increase in oxidative stress and apoptosis was observed in the cardiac region of zebrafish after exposure to flumioxazin. The antioxidant astaxanthin reversed the cardiac malformations, excessive production of reactive oxygen species (ROS), and expression of genes for cardiac developmental and apoptosis regulation induced by flumioxazin. In addition, flumioxazin also activated aryl hydrocarbon receptor (AhR) signaling pathway genes (aryl hydrocarbon receptor 2 [ahr2], cytochrome p450 family subfamily a [cyp1a1], and b [cyp1b1]) and increased the concentration of porphyrins. The results suggest that excessive ROS production, which could be mediated through AhR, led to apoptosis, contributing to the cardiotoxicity of flumioxazin in zebrafish embryos.
  [Ma, J., Jiang, P., Huang, Y., Lu, C., Tian, G., Xiao, X., Meng, Y., Xiong, X., Cheng, B., Wang, D. and Lu, H. (2023), Oxidative stress contributes to flumioxazin-induced cardiotoxicity in zebrafish embryos. Environ Toxicol Chem, 42: 2737-2746. https://doi.org/10.1002/etc.5746]
• Oxidative Stress, Cytotoxic and Inflammatory Effects of Azoles Combinatorial Mixtures in Sertoli TM4 Cells
  Triazole and imidazole fungicides are an emerging class of contaminants with an increasing and ubiquitous presence in the environment. In mammals, their reproductive toxicity has been reported. Concerning male reproduction, a combinatorial activity of tebuconazole (TEB; triazole fungicide) and econazole (ECO; imidazole compound) in inducing mitochondrial impairment, energy depletion, cell cycle arrest, and the sequential activation of autophagy and apoptosis in Sertoli TM4 cells (SCs) has recently been demonstrated. Given the strict relationship between mitochondrial activity and reactive oxygen species (ROS), and the causative role of oxidative stress (OS) in male reproductive dysfunction, the individual and combined potential of TEB and ECO in inducing redox status alterations and OS was investigated. Furthermore, considering the impact of cyclooxygenase (COX)-2 and tumor necrosis factor-alpha (TNF-α) in modulating male fertility, protein expression levels were assessed. In the present study, we demonstrate that azoles-induced cytotoxicity is associated with a significant increase in ROS production, a drastic reduction in superoxide dismutase (SOD) and GSH-S-transferase activity levels, and a marked increase in the levels of oxidized (GSSG) glutathione. Exposure to azoles also induced COX-2 expression and increased TNF-α production. Furthermore, pre-treatment with N-acetylcysteine (NAC) mitigates ROS accumulation, attenuates COX-2 expression and TNF-α production, and rescues SCs from azole-induced apoptosis, suggesting a ROS-dependent molecular mechanism underlying the azole-induced cytotoxicity.
  [Petricca, S., Carnicelli, V., Luzi, C., Cinque, B., Celenza, G., & Iorio, R. (2023). Oxidative Stress, Cytotoxic and Inflammatory Effects of Azoles Combinatorial Mixtures in Sertoli TM4 Cells. Antioxidants (Basel, Switzerland), 12(6), 1142. https://doi.org/10.3390/antiox12061142]
• Triazole pesticides exposure impaired steroidogenesis associated to an increase in AHR and CAR expression in testis and altered sperm parameters in chicken
  Since several decades, we observe the decline of various bird populations that could be partly linked to the agricultural intensification and the use of large amount of pesticides. Even if triazoles compounds are the most widely used fungicides, their effects on the reproductive parameters in birds are not clearly known. In the present study, we investigated the in vitro effects of 8 triazoles compounds alone (propiconazole (PP, from 0 to 10 µM), prothioconazole (PT), epoxiconazole (Epox), tetraconazole (TT), tebuconazole (TB), difenoconazole (Dif), cyproconazole (Cypro), metconazole (MC) (from 0 to 1 mM)) on the male chicken reproductive functions by using testis explants, primary Sertoli cells and sperm samples. In testis, all triazoles at the higher concentrations for 48 h inhibited lactate and testosterone secretion mostly in association with reduced expression of HSD3B and/or STAR mRNA levels. These data were also associated with increased expression of the nuclear receptors Aryl Hydrocarbon Receptor (AHR) and Constitutive Androstane Receptor (CAR) mRNA levels in testis and for all triazoles except for PP a reduction in Sertoli cell viability. When focusing on the sperm parameters, we demonstrated that most of the triazoles (MC, Epox, Dif, TB, TT and Cypro) at 0.1 or 1 mM for either 2, 12 or 24 min of exposure decreased sperm motility and velocity and increased the percentage of spermatozoa abnormal morphology. At the opposite, PP increased sperm motility in a dose dependent manner after 2 min of exposure whereas no significant effect was observed in response to PT whatever the dose and the time of exposure. Moreover, these effects were associated with an increase in the production of reactive oxygen species in spermatozoa. Taken together, most of the triazoles compounds impair testis steroidogenesis and semen parameters potentially through an increase in AHR and CAR expression and in oxidative stress, respectively.
  [Serra, L., Bourdon, G., Estienne, A., Fréville, M., Ramé, C., Chevaleyre, C., Didier, P., Chahnamian, M., Ganier, P., Pinault, F., Froment, P., & Dupont, J. (2023). Triazole pesticides exposure impaired steroidogenesis associated to an increase in AHR and CAR expression in testis and altered sperm parameters in chicken. Toxicology reports, 10, 409–427. https://doi.org/10.1016/j.toxrep.2023.03.005]
• Assessment of genotoxicity and oxidative stress in pregnant women contaminated to organochlorine pesticides and its correlation with pregnancy outcome
  The present study was aimed to assess the correlation between transplacental transfer of xenobiotics and resulting biochemical alterations (including genotoxicity and oxidative stress) in non-occupational pregnant women of North India along with the effect on pregnancy outcomes. Maternal and cord blood samples were collected from 221 healthy mother-infant couples and divided according to their gestational age and birth weight. Genotoxic effects in mother and cord blood were examined using comet assay. The quantitative determination of Organo-chlorine pesticides in blood serum of study population was carried out using gas chromatography-mass spectrometry (GC-MS). Notably higher Organo-chlorine pesticides levels were observed in maternal blood of preterm than term subjects for almost all of the compounds detected, with the maximum concentration found for aldrin (3.26 mg/l) in maternal blood and dieldrin (2.69 mg/l) in cord blood. The results showed a significant increment in olive tail moment, tail full length, catalase, super-oxide dismutase, and malondialdehyde levels whereas lower glutathione reductase and peroxidase were found in preterm babies when compared with term group and it varied in the order: maternal blood > cord blood. A clear trend was observed for preterm babies with their lower birth weight and cesarean mode of delivery. Therefore, reduction in birth weight in newborns may be the consequence of increased oxidative damage and genotoxicity brought about by pesticides and these markers could be employed for early detection of pesticides related ailments and toxicities. To the best of our knowledge, this was a pioneering study and it may help to increase our knowledge with regard to xenobiotic exposure in biological system and the need for stringent guidelines for agricultural use of pesticides.
  [Dwivedi, N., Mahdi, A.A., Deo, S., Ahmad, M.K. and Kumar, D. Environmental Research, 204, p.112010.]
• Cyantraniliprole impairs reproductive parameters by inducing oxidative stress in adult female wistar rats
  Cyantraniliprole is a synthetic insecticide used to control pests of up to 23 different types of crops. It is able to modulate ryanodine-like calcium channels, which are widely found in the organism of insects and mammals. The objective of this research was to verify the possible reproductive effects of adult female Wistar rats exposure to cyantraniliprole. Animals (67 days old) were exposed to the chemical at doses of 10 or 150 mg/kg/day, orally, for 28 consecutive days (control animals received only the vehicle). Vaginal secretions were collected during the exposure period to assess the regularity of the estrous cycle; the liver, kidneys, pituitary gland, adrenal gland, uterus, and ovaries were collected and weighed; reproductive organs were assessed for histopathological evaluation and for biochemical markers of oxidative stress and progesterone plasma level was measured. Both doses caused negative changes in the morphology and redox system of the uterus and ovaries. Animals exposed to 10 mg/kg also exhibited higher level of plasma progesterone, elevated levels of lipid peroxidation in reproductive organs, increased superoxide dismutase activity in the uterus and glutathione peroxidase activity on the ovary, while the 150 mg/kg group exhibited an increment in estrous cycle length and diminished uterine glandular epithelium. Based on these results, we conclude that cyantraniliprole may have acted as an endocrine disruptor, and its effects are mediated by oxidative stress.
  [da Silva Scarton, S. R., Tsuzuki, F., Guerra, M. T., Dos Santos, D. P., Dos Santos, A. C., Guimarães, A. T. B., Simão, A. N. C., Beu, C. C. L., & Fernades, G. S. A. (2022). Cyantraniliprole impairs reproductive parameters by inducing oxidative stress in adult female wistar rats. Reproductive toxicology (Elmsford, N.Y.), 107, 166–174. https://doi.org/10.1016/j.reprotox.2021.12.009]
• Oxidative stress of glyphosate, AMPA and metabolites of pyrethroids and chlorpyrifos pesticides among primary school children in Cyprus
  Exposure to various pesticides, such as pyrethroids and chlorpyrifos, has been previously associated with adverse effects on children's health. Scientific evidence on the human toxicity of glyphosate (GLY) and its primary metabolite, aminomethylphosphonic acid (AMPA) is limited, particularly for children. This study aimed to i) assess the exposure determinants of the studied pesticides measured in children in Cyprus, and ii) determine the association between the urinary pesticides and the biomarkers of DNA and lipid oxidative damage. A children's health study was set up in Cyprus (ORGANIKO study) by aligning it with the methodology and tools used in the European Human Biomonitoring Initiative (HBM4EU). Urinary GLY and AMPA, pyrethroid metabolites and the chlorpyrifos metabolite TCPy were measured in 177 children aged 10–11 years old, using mass spectrometry. Oxidative stress was assessed with 8-iso-prostaglandin F2a (8-iso-PGF2α) as a marker of lipid damage and 8-hydroxy-2′-deoxyguanosine (8-OHdG) as a DNA oxidative damage marker, both measured with immunoassays. Questionnaires about demographic characteristics, pesticide usage, and dietary habits were filled out by the parents. Μultivariable regression models examined associations between pesticides and biomarkers of effect using two creatinine adjustments (cr1: adding it as covariate and cr2: biomarkers of exposure and effect were creatinine-adjusted). Parental educational level was a significant predictor of urinary pyrethroids but not for GLY/AMPA. Median [interquartile range, IQR] values for GLY and AMPA were 0.05). Similar significant associations with 8-OHdG were shown for a pyrethroid metabolite (3-PBA) and the chlorpyrifos metabolite (TCPy). No associations were observed between the aforementioned pesticides and 8-iso-PGF2α (p > 0.05). This is the first children's health dataset demonstrating the association between AMPA and DNA oxidative damage, globally. More data is needed to replicate the observed trends in other children's populations around the globe.

  Exposure to various pesticides, such as pyrethroids and chlorpyrifos, has been previously associated with adverse effects on children's health. Scientific evidence on the human toxicity of glyphosate (GLY) and its primary metabolite, aminomethylphosphonic acid (AMPA) is limited, particularly for children. This study aimed to i) assess the exposure determinants of the studied pesticides measured in children in Cyprus, and ii) determine the association between the urinary pesticides and the biomarkers of DNA and lipid oxidative damage.

  Methods

  A children's health study was set up in Cyprus (ORGANIKO study) by aligning it with the methodology and tools used in the European Human Biomonitoring Initiative (HBM4EU). Urinary GLY and AMPA, pyrethroid metabolites and the chlorpyrifos metabolite TCPy were measured in 177 children aged 10–11 years old, using mass spectrometry. Oxidative stress was assessed with 8-iso-prostaglandin F2a (8-iso-PGF2α) as a marker of lipid damage and 8-hydroxy-2′-deoxyguanosine (8-OHdG) as a DNA oxidative damage marker, both measured with immunoassays. Questionnaires about demographic characteristics, pesticide usage, and dietary habits were filled out by the parents. Μultivariable regression models examined associations between pesticides and biomarkers of effect using two creatinine adjustments (cr1: adding it as covariate and cr2: biomarkers of exposure and effect were creatinine-adjusted).

  Results

  Parental educational level was a significant predictor of urinary pyrethroids but not for GLY/AMPA. Median [interquartile range, IQR] values for GLY and AMPA were  0.05). Similar significant associations with 8-OHdG were shown for a pyrethroid metabolite (3-PBA) and the chlorpyrifos metabolite (TCPy). No associations were observed between the aforementioned pesticides and 8-iso-PGF2α (p > 0.05).

  Conclusions

  This is the first children's health dataset demonstrating the association between AMPA and DNA oxidative damage, globally. More data is needed to replicate the observed trends in other children's populations around the globe.

  
  [Makris, K.C., Efthymiou, N., Konstantinou, C., Anastasi, E., Schoeters, G., Kolossa-Gehring, M. and Katsonouri, A., Environmental Research, 212, p.113316.]
• Oxidative stress, intestinal damage, and cell apoptosis: Toxicity induced by fluopyram in Caenorhabditis elegans
  Fluopyram, a succinate dehydrogenase inhibitor fungicide and nematicide, has been used extensively for agricultural pest control and toxicologically affects non-target organisms. In the present study, Caenorhabditis elegans, a well-established model organism, was used to evaluate the toxic effect of fluopyram and the possible molecular mechanisms. C. elegans was exposed to fluopyram for 24 h at three sublethal concentrations (0.01, 0.05 and 0.25 mg/L) and the physiological, biochemical, and molecular indicators were examined. The results showed that sublethal exposure to fluopyram could cause damage to growth, locomotion behavior, feeding, lifespan and reproduction of the nematodes. Fluopyram exposure induced oxidative stress as indicated by increase of ROS production, lipofuscin and lipid accumulation, and MDA level in the nematodes. In contrast, exposure to fluopyram significantly decreased the activities of target enzyme SDH and antioxidant enzymes including SOD, CAT and GST. Moreover, the expression of genes associated with oxidative stress (e.g., gst-4, sod-3, fat-7, mev-1 and daf-16), intestinal damage (e.g., mtm-6, nhx-2, opt-2, pkc-3, par-6, act-5 and egl-8), and cell apoptosis (e.g., ced-13, ced-3, egl-38, efl-2, cep-1 and lgg-1) was significantly influenced after exposure to fluopyram. According to Pearson correlation analyses, significant correlation existed between 190 pairs of parameters, which indicated that fluopyram induced multiple toxic related effects in C. elegans. These findings suggest that oxidative stress, intestinal damage, and cell apoptosis may play major roles in toxicity of fluopyram in the nematodes.
  [Liu, Y., Zhang, W., Wang, Y., Liu, H., Zhang, S., Ji, X., & Qiao, K. (2022). Oxidative stress, intestinal damage, and cell apoptosis: Toxicity induced by fluopyram in Caenorhabditis elegans. Chemosphere, 286(Pt 3), 131830. https://doi.org/10.1016/j.chemosphere.2021.131830]
• PFAS Molecules: A Major Concern for the Human Health and the Environment
  Per- and polyfluoroalkyl substances (PFAS) are a group of over 4700 heterogeneous compounds with amphipathic properties and exceptional stability to chemical and thermal degradation. The unique properties of PFAS compounds has been exploited for almost 60 years and has largely contributed to their wide applicability over a vast range of industrial, professional and non-professional uses. However, increasing evidence indicate that these compounds represent also a serious concern for both wildlife and human health as a result of their ubiquitous distribution, their extreme persistence and their bioaccumulative potential. In light of the adverse effects that have been already documented in biota and human populations or that might occur in absence of prompt interventions, the competent authorities in matter of health and environment protection, the industries as well as scientists are cooperating to identify the most appropriate regulatory measures, substitution plans and remediation technologies to mitigate PFAS impacts. In this review, starting from PFAS chemistry, uses and environmental fate, we summarize the current knowledge on PFAS occurrence in different environmental media and their effects on living organisms, with a particular emphasis on humans. Also, we describe present and provisional legislative measures in the European Union framework strategy to regulate PFAS manufacture, import and use as well as some of the most promising treatment technologies designed to remediate PFAS contamination in different environmental compartments.
  [Panieri, E. et al. (2022) Pfas molecules: A major concern for the human health and the environment, Toxics. Available at: https://www.mdpi.com/2305-6304/10/2/44. ]
• Review of molecular and biochemical responses during stress induced stimulation and hormesis in insects
  The biphasic hormetic response to stress, defined by low-dose stimulation and high-dose inhibition is frequently observed in insects. Various molecular and biochemical responses associated with hormesis in insects have been reported in many studies, but no synthesis of all these findings has been undertaken. We conducted a systematic literature review, analyzing papers demonstrating phenotypic stimulatory effect(s) following exposure to stress where molecular or biochemical response(s) were also examined. Responses observed included stimulation of reproduction, survival and longevity, growth and development, and tolerance to temperature, chemical, or starvation and desiccation, in response to stressors including pesticides, oxidative stress, temperature, crowding and starvation, and radiation. Phenotypic stimulation ranged from <25% increased above controls to >100%. Reproductive stimulation was frequently <25% increased above controls, while stimulated temperature tolerance was frequently >100% increased. Molecular and biochemical responses had obvious direct connections to phenotypic responses in many cases, although not in all instances. Increased expression of heat shock proteins occurred in association with stimulated temperature tolerance, and increased expression of detoxification genes with stimulated pesticide or chemical tolerance, but also stimulated reproduction. Changes in the expression or activity of antioxidants were frequently associated with stimulation of longevity and reproduction. Stress induced changes in vitellogenin and juvenile hormone and genes in the IIS/TOR signalling pathway – which are directly responsible for regulating growth, development, and reproduction – were also reported. Our analysis showed that coordination of expression of genes or proteins associated with protection from oxidative stress and DNA and protein damage is important in the hormetic responses of insects.
  [Rachel R. Rix, G. Christopher Cutler, Review of molecular and biochemical responses during stress induced stimulation and hormesis in insects, Science of The Total Environment, Volume 827, 2022, 154085, ISSN 0048-9697, https://doi.org/10.1016/j.scitotenv.2022.154085.]
• Single and joint toxicity assessment of acetamiprid and thiamethoxam neonicotinoids pesticides on biochemical indices and antioxidant enzyme activities of a freshwater fish Catla catla
  Neonicotinoids pesticides are extensively used in many countries due to their high insect selectivity. Acetamiprid and thiamethoxam are the neonicotinoids most commonly detected in the aquatic environment. This work examined the single and joint toxicity of acetamiprid and thiamethoxam in a freshwater fish Catla catla. Fish were exposed to acetamiprid (0.5 mg/L and 1 mg/L), thiamethoxam (0.01 mg/L and 0.5 mg/L) and their binary mixtures (0.5 mg/L of acetamiprid and 0.01 mg/L of thiamethoxam) for 96 h. The stress biomarkers such as glucose, protein, electrolytes, Na+/K+ -ATPase and oxidative stress were evaluated. Among the biochemical parameters, plasma protein, electrolytes (sodium, potassium and chloride) and gill ATPase activity were decreased in response to individual and binary mixtures treatments. In contrast, blood glucose level showed significant increase in all the treatments. Exposure to various concentrations of acetamiprid and thiamethoxam resulted in significant decrease in superoxide dismutase (SOD) activity in the gill tissue. However, SOD activity was significantly elevated during binary mixtures treatment. Glutathione peroxidase (GPx), catalase (CAT), glutathione-S-transferase (GST) and reduced glutathione (GSH) levels in gills were decreased significantly after individual and binary mixtures treatments. Fish exposed at individual and binary mixtures significantly elevated the level of LPO in gill tissue. Our findings suggest that multi-biomarker approach can be effectively used to assess the effects of joint toxicity of pesticides and to monitor the neonicotinoids pesticides in the aquatic environment.
  [Veedu, S. K., Ayyasamy, G., Tamilselvan, H., & Ramesh, M. (2022). Single and joint toxicity assessment of acetamiprid and thiamethoxam neonicotinoids pesticides on biochemical indices and antioxidant enzyme activities of a freshwater fish Catla catla. Comparative biochemistry and physiology. Toxicology & pharmacology : CBP, 257, 109336. https://doi.org/10.1016/j.cbpc.2022.109336]
• Subchronic exposure to Epoxiconazole induced-heart damage in male Wistar rats
  

  Highlights

  • EPX increases absolute and relative heart weights of Wistar rats.
  • EPX causes oxidative stress in the heart tissue of male Wistar rats.
  • EPX enhances MDA, PC levels and induces DNA damage.
  • EPX provokes disturbance of the cardiac antioxidant and cholinergic systems.
  • EPX induces histopathological alterations.

  Abstract

  Epoxiconazole is a worldwide fungicide used to control fungal diseases. Although to its hazardous effects in non-target species, little information is available in the literature to show the cardiotoxic effects of EPX in male rats. Thus, our investigation aimed to assess the outcomes of EPX exposure on some biochemical parameters, the generation of oxidative stress, DNA fragmentation and histopathological alterations in the heart tissue. EPX was administered orally at doses of 8, 24, 40 and 56 mg/kg body weight, representing, respectively NOEL (No observed effect level), NOEL× 3, NOEL× 5 and NOEL× 7 for 28 consecutive days in male Wistar rats. Our results show that EPX induced a significant decrease of cardiac acetylcholinesterase, an increase of biochemical markers, such as creatinine phosphokinase (CPK) and a perturbation of the lipid profile. Furthermore, EPX caused diverse histological modifications in the myocardium, including congestion of cardiac blood vessels, cytoplasmic vacuolization, leucocytic infiltration and hemorrhage. Indeed, we have shown that EPX induces increase of lipid peroxidation, protein oxidation levels and DNA damage. On the other hand, we have found an increase of the antioxidant enzymes activity such as catalase (CAT) and superoxide dismutase (SOD) activities. The glutathione peroxidase and glutathione S tranferase initially enhanced at the doses of 8, 24, and 40 mg/kg b.w. and then decreased at the dose of 56 mg/kg b.w. In conclusion, our work has shown that EPX causes cardiotoxic effects by altering redox status and damaging heart tissue.

  
  [Hamdi, H. et al. (2022) ‘Subchronic exposure to epoxiconazole induced-heart damage in male Wistar Rats’, Pesticide Biochemistry and Physiology, 182, p. 105034. doi:10.1016/j.pestbp.2022.105034. ]
• A comprehensive review on chlorpyrifos toxicity with special reference to endocrine disruption: Evidence of mechanisms, exposures and mitigation strategies
  Chlorpyrifos (CPF) is a broad-spectrum chlorinated organophosphate (OP) pesticide used for the control of a variety of insects and pathogens in crops, fruits, vegetables, as well as households, and various other locations. The toxicity of CPF has been associated with neurological dysfunctions, endocrine disruption, and cardiovascular diseases (CVDs). It can also induce developmental and behavioral anomalies, hematological malignancies, genotoxicity, histopathological aberrations, immunotoxicity, and oxidative stress as evidenced by animal modeling. Moreover, eye irritation and dermatological defects are also reported due to CPF toxicity. The mechanism of action of CPF involves blocking the active sites of the enzyme, acetylcholinesterase (AChE), thereby producing adverse nervous system effects. Although CPF has low persistence in the body, its active metabolites, 3,5,6-trichloro-2-pyridinol (TCP), and chlorpyrifos-oxon (CPO) are comparatively more persistent, albeit equally toxic, and thus produce serious health complications. The present review has been compiled taking into account the work related to CPF toxicity and provides a brief compilation of CPF-induced defects in animals and humans, emphasizing the abnormalities leading to endocrine disruption, neurotoxicity, reproductive carcinogenesis, and disruptive mammary gland functionality. Moreover, the clinical signs and symptoms associated with the CPF exposure along with the possible pharmacological treatment are reported in this treatise. Additionally, the effect of food processing methods in reducing CPF residues from different agricultural commodities and dietary interventions to curtail the toxicity of CPF has also been discussed.
  [Ubaid Ur Rahman, H., Asghar, W., Nazir, W., Sandhu, M. A., Ahmed, A., & Khalid, N. (2021). A comprehensive review on chlorpyrifos toxicity with special reference to endocrine disruption: Evidence of mechanisms, exposures and mitigation strategies. The Science of the total environment, 755(Pt 2), 142649. https://doi.org/10.1016/j.scitotenv.2020.142649]
• Alterations in blood parameters, DNA damage, oxidative stress and antioxidant enzymes and immune-related genes expression in Nile tilapia (Oreochromis niloticus) exposed to glyphosate-based herbicide
  In this study, effects of different concentrations (0, 5, 10, 20, 30, and 40 mg/L) of glyphosate-based herbicide (GBH) on Nile tilapia (Oreochromis niloticus) were investigated after a 14-day of exposure. After determination of LC50 value, effects of GBH on hematological and serum biochemical parameters in blood samples, DNA damage, lipid peroxidation and catalase activity in liver tissues, expression levels of antioxidant enzyme-related genes (SOD, CAT, GPx, and GST) and immune-related genes (TGF-β, TGF-α and IL1-β) were evaluated. The LC50 value has been found as 44.4 mg/L for GBH. GBH exposure at all concentrations caused alterations in blood parameters. GBH induced oxidative stress in liver and DNA damage in blood. Antioxidant enzyme-related genes were significantly up-regulated to suppress oxidative stress. On the other hand, the expression levels of immune-related genes decreased in fish exposure to particularly ≥20 mg/L GBH.
  [Acar, Ü., İnanan, B. E., Navruz, F. Z., & Yılmaz, S. (2021). Alterations in blood parameters, DNA damage, oxidative stress and antioxidant enzymes and immune-related genes expression in Nile tilapia (Oreochromis niloticus) exposed to glyphosate-based herbicide. Comparative biochemistry and physiology. Toxicology & pharmacology : CBP, 249, 109147. https://doi.org/10.1016/j.cbpc.2021.109147]
• Difenoconazole induces cardiovascular toxicity through oxidative stress-mediated apoptosis in early life stages of zebrafish (Danio rerio)
  Difenoconazole (DIF), a common broad-spectrum triazole fungicide, is associated with an increased risk of cardiovascular diseases. Unfortunately, little attention has been paid to the mechanisms underlying this association. In this study, zebrafish embryos were exposed to DIF (0, 0.3, 0.6 and 1.2 mg/L) from 4 to 96 h post fertilization (hpf) and cardiovascular toxicity was evaluated. Our results showed that DIF decreased hatching rate, survival rate and heart rate, with increased malformation rate. Cardiovascular deformities are the most prominent, including pericardial edema, abnormal cardiac structure and disrupted vascular pattern in two transgenic zebrafish models (myl7:egfp and fli1:egfp). DIF exacerbated oxidative stress by via accumulation of reactive oxygen species (ROS) and inhibition of antioxidant enzyme. Cardiovascular apoptosis was triggered through increased expression of p53, bcl-2, bax and caspase 9, while DIF suppressed the transcription of key genes involved in calcium signaling and cardiac muscle contraction. These adverse outcomes were restored by the antioxidant N-acetyl-L-cysteine (NAC), indicating that oxidative stress played a crucial role in DIF-induced cardiovascular toxicity caused by apoptosis and inhibition of cardiac muscle contraction. Taken together, this study revealed the key role of oxidative stress in DIF-induced cardiovascular toxicity and provided novel insights into strategies to mitigate its toxicity.
  [Zhu, J., Liu, C., Wang, J., Liang, Y., Gong, X., You, L., Ji, C., Wang, S. L., Wang, C., & Chi, X. (2021). Difenoconazole induces cardiovascular toxicity through oxidative stress-mediated apoptosis in early life stages of zebrafish (Danio rerio). Ecotoxicology and environmental safety, 216, 112227. Advance online publication. https://doi.org/10.1016/j.ecoenv.2021.112227]
• From the effective herbicide to the environmental contaminant: A review of recent studies on quinclorac
  Quinclorac is a specific auxin herbicide with chloro-quinolinecarboxylic acid structure and has been widely recognized as the preferred option for controlling both broadleaf weed and barnyard grass. However, the extensive application of quinclorac has resulted in the evolution of resistant plants, the frequent detection in the environment, and the hazard to non-target organisms. Consequently, the aim of this review is to comprehensively summarize the recent investigations on quinclorac, so as to help promoting the further study for reasonably employing quinclorac and effectively controlling the related risks. In this review, the action mechanism of quinclorac was discussed based on the structure and property, suggesting the involvements of ethylene, phytohormone and even cyanide in sensitive plants. The evolved resistance might be related to auxin production, gene expression, translocation and metabolism. By establishing the reliable methods in previous studies, the quinclorac residue was widely detected and could cause the obvious toxicity such as physiological changes and oxidative stress. Nevertheless, there is still a lack of the remediation technique, which can be efficiently applied in practical engineering.
  [Song, D. et al. (2021) From the effective herbicide to the environmental contaminant: A review of recent studies on quinclorac, Environmental and Experimental Botany. Available at: https://www.sciencedirect.com/science/article/abs/pii/S0098847221003361. ]
• Genotoxicity evaluation of 2,4-D, dicamba and glyphosate alone or in combination with cell reporter assays for DNA damage, oxidative stress and unfolded protein response
  The current generation of carcinogenicity tests is often insufficient to predict cancer outcomes from pesticide exposures. In order to facilitate health risk assessment, The International Agency for Research on Cancer identified 10 key characteristics which are commonly exhibited by human carcinogens. The ToxTracker panel of six validated GFP-based mouse embryonic stem reporter cell lines is designed to measure a number of these carcinogenic properties namely DNA damage, oxidative stress and the unfolded protein response. Here we present an evaluation of the carcinogenic potential of the herbicides glyphosate, 2,4-D and dicamba either alone or in combination, using the ToxTracker assay system. The pesticide 2,4-D was found to be a strong inducer of oxidative stress and an unfolded protein response. Dicamba induced a mild oxidative stress response, whilst glyphosate did not elicit a positive outcome in any of the assays. The results from a mixture of the three herbicides was primarily an oxidative stress response, which was most likely due to 2,4-D with dicamba or glyphosate only playing a minor role. These findings provide initial information regarding the risk assessment of carcinogenic effects arising from exposure to a mixture of these herbicides.
  [Mesnage, R. et al. (2021) ‘Genotoxicity evaluation of 2,4-D, dicamba and glyphosate alone or in combination with cell reporter assays for DNA damage, oxidative stress and unfolded protein response’, Food and Chemical Toxicology, 157, p. 112601. doi:10.1016/j.fct.2021.112601. ]
• A dose of experimental hormesis: When mild stress protects and improves animal performance
  The adaptive response characterized by a biphasic curve is known as hormesis. In a hormesis framework, exposure to low doses leads to protective and beneficial responses while exposures to high doses are damaging and detrimental. Comparative physiologists have studied hormesis for over a century, but our understanding of hormesis is fragmented due to rifts in consensus and taxonomic-specific terminology. Hormesis has been and is currently known by multiple names; preconditioning, conditioning, pretreatment, cross tolerance, adaptive homeostasis, and rapid stress hardening (mostly low temperature: rapid cold hardening). These are the most common names used to describe adaptive stress responses in animals. These responses are mechanistically similar, while having stress-specific responses, but they all can fall under the umbrella of hormesis. Here we review how hormesis studies have revealed animal performance benefits in response to changes in oxygen, temperature, ionizing radiation, heavy metals, pesticides, dehydration, gravity, and crowding. And how almost universally, hormetic responses are characterized by increases in performance that include either increases in reproduction, longevity, or both. And while the field can benefit from additional mechanistic work, we know that many of these responses are rooted in increases of antioxidants and oxidative stress protective mechanisms; including heat shock proteins. There is a clear, yet not fully elucidated, overlap between hormesis and the preparation for oxidative stress theory; which predicts part of the responses associated with hormesis. We discuss this, and the need for additional work into animal hormetic effects particularly focusing on the cost of hormesis.
  [Raymond Berry, Giancarlo López-Martínez, A dose of experimental hormesis: When mild stress protects and improves animal performance, Comparative Biochemistry and Physiology Part A: Molecular & Integrative Physiology, Volume 242, 2020, 110658, ISSN 1095-6433, https://doi.org/10.1016/j.cbpa.2020.110658.]
• Cellular injury leading to oxidative stress in acute poisoning with potassium permanganate/oxalic acid, paraquat, and glyphosate surfactant herbicide
  Previous studies on human acute kidney injury (AKI) following poisoning with potassium permanganate/oxalic acid (KMnO4/H2C2O4), paraquat, and glyphosate surfactant herbicide (GPSH) have shown rapid and large increases in serum creatinine (sCr) that cannot be entirely explained by direct nephrotoxicity. One plausible mechanism for a rapid increase in sCr is oxidative stress. Thus, we aimed to explore biomarkers of oxidative stress, cellular injury, and their relationship with sCr, after acute KMnO4/H2C2O4, paraquat, and GPSH poisonings. Serum biomarkers [sCr, creatine (sCn), cystatin C (sCysC)] and urinary biomarkers [cytochrome C (CytoC), 8-isoprostane (8-IsoPs)] were evaluated in 105 patients [H2C2O4/KMnO4 (N = 57), paraquat, (N = 21), GPSH (N = 27)] recruited to a multicenter cohort study. We used area under the receiver operating characteristics curve (AUC-ROC) to quantify the extent of prediction of moderate to severe AKI (acute kidney injury network stage 2/3 (AKIN2/3)). Patients with AKIN2/3 showed increased levels of CytoC. Early high CytoC predicted AKIN2/3 in poisoning with KMnO4/H2C2O4 (AUC-ROC4-8h: 0.81), paraquat (AUC-ROC4-8h: 1.00), and GPSH (AUC-ROC4-8h: 0.91). 8-Isoprostane levels were not significantly elevated. Reduced sCn and increased sCr/sCn ratios were observed for 48 h post KMnO4/H2C2O4 ingestion. Paraquat exhibited a similar pattern (N = 11), however only 3 were included in our study. Increased CytoC suggests there is mitochondrial injury coupled with energy depletion. The increased sCr within 24 h could be due to increased conversion of cellular creatine to creatinine during the process of adenosine triphosphate (ATP) generation and then efflux from cells. Later increases of sCr are more likely to represent a true decrease in kidney function.
  [Wijerathna, T.M., Mohamed, F., Gawarammana, I.B., Wunnapuk, K., Dissanayake, D.M., Shihana, F. and Buckley, N.A., 2020. Environmental toxicology and pharmacology, 80, p.103510.]
• Field rates of Sivanto™ (flupyradifurone) and Transform® (sulfoxaflor) increase oxidative stress and induce apoptosis in honey bees (Apis mellifera L.)
  Pesticide exposures can have detrimental impacts on bee pollinators, ranging from immediate mortality to sub-lethal impacts. Flupyradifurone is the active ingredient in Sivanto™ and sulfoxaflor is the active ingredient in Transform®. They are both relatively new insecticides developed with an intent to reduce negative effects on bees, when applied to bee-attractive crops. With the growing concern regarding pollinator health and pollinator declines, it is important to have a better understanding of any potential negative impacts, especially sub-lethal, of these pesticides on bees. This study reports novel findings regarding physiological stress experienced by bees exposed to field application rates of these two insecticides via a Potter Tower sprayer. Two contact exposure experiments were conducted—a shorter 6-hour study and a longer 10-day study. Honey bee mortality, sugar syrup and water consumption, and physiological responses (oxidative stress and apoptotic protein assays) were assessed in bees exposed to Sivanto™ and Transform®, and compared to bees in control group. For the longer, 10-day contact exposure experiment, only the Sivanto™ group was compared to the control group, as high mortality recorded in the sulfoxaflor treatment group during the shorter contact exposure experiment, made the latter group unfeasible to test in the longer 10-days experiment. In both the studies, sugar syrup and water consumptions were significantly different between treatment groups and controls. The highest mortality was observed in Transform® exposed bees, followed by the Sivanto™ exposed bees. Estimates of reactive oxygen/nitrogen species indicated significantly elevated oxidative stress in both pesticide treatment groups, when compared to controls. Caspase-3 protein assays, an indicator of onset of apoptosis, was also significantly higher in the pesticide treatment groups. These differences were largely driven by post exposure duration, indicating sub-lethal impacts. Further, our findings also emphasize the need to revisit contact exposure impacts of Sivanto™, given the sub-lethal impacts and mortality observed in our long-term (10-day) contact exposure experiment.
  [Chakrabarti P, Carlson EA, Lucas HM, Melathopoulos AP, Sagili RR (2020) Field rates of Sivanto™ (flupyradifurone) and Transform® (sulfoxaflor) increase oxidative stress and induce apoptosis in honey bees (Apis mellifera L.). PLOS ONE 15(5): e0233033. https://doi.org/10.1371/journal.pone.0233033]
• Glyphosate and its formulation Roundup impair pig oocyte maturation
  Glyphosate, formulated as glyphosate-based herbicides (GBHs) including the best-known formulation Roundup, is the world's most widely used herbicide. During the last years, the growing and widespread use of GBHs has raised a great concern about the impact of environmental contamination on animal and human health including potential effect on reproductive systems. Using an in vitro model of pig oocyte maturation, we examined the biological impact of both glyphosate and Roundup on female gamete evaluating nuclear maturation, cytoplasmic maturation and developmental competence of oocytes, steroidogenic activity of cumulus cells as well as intracellular levels of glutathione (GSH) and ROS of oocytes. Our results indicate that although exposure to glyphosate and Roundup during in vitro maturation does not affect nuclear maturation and embryo cleavage, it does impair oocyte developmental competence in terms of blastocyst rate and cellularity. Moreover, Roundup at the same glyphosate-equivalent concentrations was shown to be more toxic than pure glyphosate, altering steroidogenesis and increasing oocyte ROS levels, thus confirming that Roundup adjuvants enhance glyphosate toxic effects and/or are biologically active in their side-effect and therefore should be considered and tested as active ingredients.
  [Spinaci, M., Nerozzi, C., Tamanini, C.l. et al. Glyphosate and its formulation Roundup impair pig oocyte maturation. Sci Rep 10, 12007 (2020). https://doi.org/10.1038/s41598-020-68813-6]
• Glyphosate Induces Metaphase II Oocyte Deterioration and Embryo Damage by Zinc Depletion and Overproduction of Reactive Oxygen Species
  Glyphosate is the most popular herbicide used in modern agriculture, and its use has been increasing substantially since its introduction. Accordingly, glyphosate exposure from food and water, the environment, and accidental and occupational venues has also increased. Recent studies have demonstrated a relationship between glyphosate exposure and a number of disorders such as cancer, immune and metabolic disorders, endocrine disruption, imbalance of intestinal flora, cardiovascular disease, and infertility; these results have given glyphosate a considerable amount of media and scientific attention. Notably, glyphosate is a powerful metal chelator, which could help explain some of its effects. Recently, our findings on 2,3-dimercapto-1-propanesulfonic acid, another metal chelator, showed deterioration of oocyte quality. Here, to generalize, we investigated the effects of glyphosate (0 – 300 μM) on metaphase II mouse oocyte quality and embryo damage to obtain insight on its mechanisms of cellular action and the tolerance of oocytes and embryos towards this chemical. Our work shows for the first time that glyphosate exposure impairs metaphase II mouse oocyte quality via two mechanisms: 1) disruption of the microtubule organizing center and chromosomes such as anomalous pericentrin formation, spindle fiber destruction and disappearance, and defective chromosomal alignment and 2) substantial depletion of intracellular zinc bioavailability and enhancement of reactive oxygen species accumulation. Similar effects were found in embryos. These results may help clarify the effects of glyphosate exposure on female fertility and provide counseling and preventative steps for excessive glyphosate intake and resulting oxidative stress and reduced zinc bioavailability.
  [Yahfoufi, Z. A., Bai, D., Khan, S. N., Chatzicharalampous, C., Kohan-Ghadr, H. R., Morris, R. T., & Abu-Soud, H. M. (2020). Glyphosate Induces Metaphase II Oocyte Deterioration and Embryo Damage by Zinc Depletion and Overproduction of Reactive Oxygen Species. Toxicology, 439, 152466. https://doi.org/10.1016/j.tox.2020.152466]
• Low doses of the neonicotinoid insecticide imidacloprid induce ROS triggering neurological and metabolic impairments in Drosophila
  Declining insect population sizes are provoking grave concern around the world as insects play essential roles in food production and ecosystems. Environmental contamination by intense insecticide usage is consistently proposed as a significant contributor, among other threats. Many studies have demonstrated impacts of low doses of insecticides on insect behavior, but have not elucidated links to insecticidal activity at the molecular and cellular levels. Here, the histological, physiological, and behavioral impacts of imidacloprid are investigated in Drosophila melanogaster, an experimental organism exposed to insecticides in the field. We show that oxidative stress is a key factor in the mode of action of this insecticide at low doses. Imidacloprid produces an enduring flux of Ca2+ into neurons and a rapid increase in levels of reactive oxygen species (ROS) in the larval brain. It affects mitochondrial function, energy levels, the lipid environment, and transcriptomic profiles. Use of RNAi to induce ROS production in the brain recapitulates insecticide-induced phenotypes in the metabolic tissues, indicating that a signal from neurons is responsible. Chronic low level exposures in adults lead to mitochondrial dysfunction, severe damage to glial cells, and impaired vision. The potent antioxidant, N-acetylcysteine amide (NACA), reduces the severity of a number of the imidacloprid-induced phenotypes, indicating a causal role for oxidative stress. Given that other insecticides are known to generate oxidative stress, this research has wider implications. The systemic impairment of several key biological functions, including vision, reported here would reduce the resilience of insects facing other environmental challenges.
  [Martelli, F., Zhongyuan, Z., Wang, J., Wong, C.O., Karagas, N.E., Roessner, U., Rupasinghe, T., Venkatachalam, K., Perry, T., Bellen, H.J. and Batterham, P., 2020. Proceedings of the National Academy of Sciences, 117(41), pp.25840-25850.]
• Ovarian mitochondrial and oxidative stress proteins are altered by glyphosate exposure in mice
  Glyphosate (GLY) usage for weed control is extensive. To investigate ovarian impacts of chronic GLY exposure, female C57BL6 mice were orally administered saline as vehicle control (CT) or GLY at 0.25 (G0.25), 0.5 (G0.5), 1.0 (G1.0), 1.5 (G1.5), or 2 (G2.0) mg/kg for five days per wk. for 20 wks. Feed intake increased (P < .05) in G1.5 and G2.0 mice and body weight increased (P < .05) in G1.0 mice. There was no impact of GLY on estrous cyclicity, nor did GLY affect circulating levels of 17β-estradiol or progesterone. Exposure to GLY did not impact heart, liver, spleen, kidney or uterus weight. Both ovarian weight and follicle number were increased (P < .05) by G2.0 but not affected at lower GLY concentrations. There were no detectable effects of GLY on ovarian protein abundance of pAKT, AKT, pAKT:AKT, γH2AX, STAR, CYP11A1, HSD3B, CYP19A, ERA or ERB. Increased (P < .05) abundance of ATM protein was observed at G0.25 but not higher GLY doses. A dose-dependent effect (P < .10) of GLY exposure on ovarian protein abundance as quantified by LC-MS/MS was observed (G0.25–4 increased, 19 decreased; G0.5–5 increased, 25 decreased; G1.0–65 increased, 7 decreased; G1.5–145 increased, 2 decreased; G2.0–159 increased, 4 decreased). Pathway analysis was performed using DAVID and identified glutathione metabolism, metabolic and proteasome pathways as GLY exposure targets. These data indicate that chronic low-level exposure to GLY alters the ovarian proteome and may ultimately impact ovarian function.
  [Ganesan, S., & Keating, A. F. (2020). Ovarian mitochondrial and oxidative stress proteins are altered by glyphosate exposure in mice. Toxicology and applied pharmacology, 402, 115116. https://doi.org/10.1016/j.taap.2020.115116]
• Residue and toxicity of cyantraniliprole and its main metabolite J9Z38 in soil-earthworm microcosms
  As part of a new generation of diamide insecticides, cyantraniliprole has broad application prospects. In the present study, a QuEChERS-UPLC-MS/MS method was established to determine the residues of cyantraniliprole and its main metabolite J9Z38 in soil and earthworms. Moreover, the accumulation and toxicity of cyantraniliprole and J9Z38 in earthworms were evaluated. The present results show that the detection method of cyantraniliprole and J9Z38 has high sensitivity and accuracy, which could be used for the accurate quantification of cyantraniliprole and J9Z38 residues in soil and earthworms. Additionally, cyantraniliprole degraded faster than its main metabolite J9Z38 in the artificial soil. Moreover, the bioenrichment efficiency of cyantraniliprole was higher than J9Z38. The toxicity test result showed that cyantraniliprole and J9Z38 could induce oxidative stress effect in earthworms from 5.0 mg/kg, finally resulting in cellular damage. Moreover, the oxidative damage degree induced by cyantraniliprole was higher than J9Z38. Combining the results of residue test and toxicity test, although cyantraniliprole degraded faster than its main metabolite J9Z38 in the artificial soil, its risk to earthworms was higher than J9Z38.
  [Zhang, X., Wang, X., Liu, Y., Fang, K., & Liu, T. (2020). Residue and toxicity of cyantraniliprole and its main metabolite J9Z38 in soil-earthworm microcosms. Chemosphere, 249, 126479. https://doi.org/10.1016/j.chemosphere.2020.126479]
• Sub-lethal Effects of Imidacloprid on Nile Tilapia (Oreochromis niloticus)
  Imidacloprid (1-(6-chloro-3-pyridylmethyl)-N-nitroimidazolidin-2-ylideneamine (CAS No: 138261–41-3), neonicotinoid insecticide, and agricultural plant protectants were applied as seed and soil treatments. The aim of the present study is to determine the effects of sub-lethal imidacloprid concentrations on the histopathology and oxidative stress parameters with lipid peroxidation (LPO) to standard non-target test organism, tilapia (Oreochromis niloticus). 50 and 100 mgL−1 imidacloprid concentrations were chosen for experimental groups with control group. Fish were stocked in 60 L glass aquaria, maintained in aerated and dechlorinated tap water. The mean weight and length of tilapia were 37.78 ± 2.19 g and 12.98 ± 0.22 cm, respectively. After 24 and 96 h exposure to sub-lethal imidacloprid concentrations, the fish were sacrificed; tissue samples of gill and liver were snap frozen in liquid nitrogen for oxidative stress parameters and LPO assays, fixed (buffered 10% formalin) for histopathology. After exposure to sub-lethal imidacloprid, LPO was induced in both tissues. MDA levels were increased in both tissues, while GSH levels were reduced at the high concentration of imidacloprid in the gill tissues after 96 h and both concentrations in the liver tissues (P < 0.05). There were no significant differences for antioxidant enzymes CAT, SOD and GPx between exposed and control groups (P > 0.05). Gill tissues revealed hyperaemia, epithelial lifting, fusion of secondary lamellae and telangiectasia, whereas hyperaemia, mononuclear cell infiltration vacuolization of hepatocytes and hydropic degeneration were observed in liver tissues. Imidacloprid is very toxic to the non-target species in the aquatic ecosystem even at sub-lethal concentrations.
  [Günal, A.Ç., Erkmen, B., Paçal, E. et al. Sub-lethal Effects of Imidacloprid on Nile Tilapia (Oreochromis niloticus). Water Air Soil Pollut 231, 4 (2020). https://doi.org/10.1007/s11270-019-4366-8]
• Synthetic Pesticides and Health in Vulnerable Populations: Agricultural Workers
  Purpose of review: This review aims to summarize epidemiological literature published between May 15, 2018, and May 14, 2019, that examines the relationship between exposure to synthetic pesticides and health of agricultural workers.

  Recent findings: Current research suggests that exposure to synthetic pesticides may be associated with adverse health outcomes. Agricultural workers represent a potentially vulnerable population, due to a combination of unique social and cultural risk factors as well as exposure to hazards inherent in agricultural work. Pesticide exposure among agricultural workers has been linked to certain cancers, DNA damage, oxidative stress, neurological disorders, and respiratory, metabolic, and thyroid effects. This review describes literature suggesting that agricultural workers exposed to synthetic pesticides are at an increased risk of certain cancers and neurological disorders. Recent research on respiratory effects is sparse, and more research is warranted regarding DNA damage, oxidative stress, metabolic outcomes, and thyroid effects.
  [Curl, C. L., Spivak, M., Phinney, R., & Montrose, L. (2020). Synthetic Pesticides and Health in Vulnerable Populations: Agricultural Workers. Current environmental health reports, 7(1), 13–29. https://doi.org/10.1007/s40572-020-00266-5]

• Tebuconazole induced oxidative stress and histopathological alterations in adult rat heart
  TEB belongs to the family of triazole fungicides and it is used to protect agricultural crop plants from fungal pathogens. The information regarding its cardiotoxic effects through different pathways particularly by perturbing the oxidative balance and causing damage to the myocardium is still limited. In the present study, oxidative and histopathologic damages caused by TEB in the cardiac tissue of male adult rats, were evaluated. Rats were exposed orally to TEB at 0.9, 9, 27 and 45 mg/kg b.w. for 28 days. Results showed that following TEB treatment malondialdehyde (MDA), protein carbonyl (PC), advanced oxidation protein product (AOPP), antioxidant enzyme activities (GPx and GR) and GSSG levels increased, while GSH levels and thus the GSH/GSSG ratio decreased. Superoxide dismutase (SOD) and catalase (CAT) initially increased at the doses of 0.9, 9 and 27 mg/kg b.w. and then decreased at the dose of 45 mg/kg b.w. Moreover, western blot analysis showed that TEB increased SOD1, CAT and HSP70 protein levels after 24 h. Furthermore, TEB induced various histological changes in the myocardium, including leucocytic infiltration, hemorrhage congestion of cardiac blood vessels and cytoplasmic vacuolization. Therefore, our investigation revealed, that TEB exhibits cardiotoxic effects by changing oxidative balance and damaging the cardiac tissue.
  [Othmène, Y. B., Hamdi, H., Amara, I., & Abid-Essefi, S. (2020). Tebuconazole induced oxidative stress and histopathological alterations in adult rat heart. Pesticide biochemistry and physiology, 170, 104671. https://doi.org/10.1016/j.pestbp.2020.104671]
• Tebuconazole induces ROS-dependent cardiac cell toxicity by activating DNA damage and mitochondrial apoptotic pathway
  Tebuconazole (TEB) is a common triazole fungicide that is widely used throughout the world in agriculture applications. We previously reported that TEB induces cardiac toxicity in rats. The aim of this study was to investigate the underlying mechanism of the toxicity induced by TEB in cardiac cells. TEB induced dose-dependent cell death in H9c2 cardiomyoblasts and in adult rat ventricular myocytes (ARVM). The comet assay and western blot analysis showed a concentration-dependent increase in DNA damage and in p53 and p21 protein levels 24 h after TEB treatment. Our findings also showed that TEB triggered the mitochondrial pathway of apoptosis as evidenced by a loss of mitochondrial transmembrane potential (ΔΨm), an increase in Bax/Bcl-2 ratio, an activation of caspase-9 and caspase-3, a cleavage of poly (ADP-ribose) polymerase (PARP) and an increase in the proportion of cells in the sub-G1 phase. In addition, TEB promoted ROS production in cardiac cells and consequently increased the amounts of MDA, the end product of lipid peroxidation. Treatment of cardiomyocytes with the ROS scavenger N-acetylcysteine reduced TEB-induced DNA damage and activation of the mitochondrial pathway of apoptosis. These results indicate that the genotoxic and cytotoxic effects of TEB are mediated through a ROS-dependent pathway in cardiac cells.
  [Ben Othmène, Y., Monceaux, K., Karoui, A., Ben Salem, I., Belhadef, A., Abid-Essefi, S., & Lemaire, C. (2020). Tebuconazole induces ROS-dependent cardiac cell toxicity by activating DNA damage and mitochondrial apoptotic pathway. Ecotoxicology and environmental safety, 204, 111040. https://doi.org/10.1016/j.ecoenv.2020.111040]
• The impact and toxicity of glyphosate and glyphosate-based herbicides on health and immunity
  Glyphosate, or N-phosphomethyl(glycine), is an organophosphorus compound and a competitive inhibitor of the shikimate pathway that allows aromatic amino acid biosynthesis in plants and microorganisms. Its utilization in broad-spectrum herbicides, such as RoundUp®, has continued to increase since 1974; glyphosate, as well as its primary metabolite aminomethylphosphonic acid, is measured in soils, water, plants, animals and food. In humans, glyphosate is detected in blood and urine, especially in exposed workers, and is excreted within a few days. It has long been regarded as harmless in animals, but growing literature has reported health risks associated with glyphosate and glyphosate-based herbicides. In 2017, the International Agency for Research on Cancer (IARC) classified glyphosate as “probably carcinogenic” in humans. However, other national agencies did not tighten their glyphosate restrictions and even prolonged authorizations of its use. There are also discrepancies between countries’ authorized levels, demonstrating an absence of a clear consensus on glyphosate to date. This review details the effects of glyphosate and glyphosate-based herbicides on fish and mammal health, focusing on the immune system. Increasing evidence shows that glyphosate and glyphosate-based herbicides exhibit cytotoxic and genotoxic effects, increase oxidative stress, disrupt the estrogen pathway, impair some cerebral functions, and allegedly correlate with some cancers. Glyphosate effects on the immune system appear to alter the complement cascade, phagocytic function, and lymphocyte responses, and increase the production of pro-inflammatory cytokines in fish. In mammals, including humans, glyphosate mainly has cytotoxic and genotoxic effects, causes inflammation, and affects lymphocyte functions and the interactions between microorganisms and the immune system. Importantly, even as many outcomes are still being debated, evidence points to a need for more studies to better decipher the risks from glyphosate and better regulation of its global utilization.
  [Peillex, C. and Pelletier, M. (2020) The impact and toxicity of glyphosate and glyphosate-based herbicides on health and immunity, Journal of Immunotoxicology. Available at: https://www.tandfonline.com/doi/full/10.1080/1547691X.2020.1804492.]
• Urinary organophosphate metabolites and oxidative stress in children living in agricultural and urban communities
  Exposure to organophosphate (OP) pesticides in children may increase oxidative stress, resulting in the development of chronic diseases. This study aims to compare urinary OP metabolites and oxidative stress between children in agricultural and urban communities. The study also investigated the factors associated with urinary OP metabolites among children. Urine samples were collected from children for measuring levels of OP metabolites, glutathione (GSH), and malondialdehyde (MDA). The remarkable findings were that total dialkylphosphate (DAP) levels detected among children in this agricultural community were significantly higher than those from the urban community (P = 0.001). Multiple linear regression showed that total diethylphosphate (DEP) levels among children in the agricultural community were negatively associated with distances from children’s residence to the agricultural fields (β ± SE. = − 1.535 ± 0.334, 95%CI = − 2.202, − 0.863) and positively associated with playing on farms (β ± SE. = 0.720 ± 0.342, 95%CI = 0.036, 1.405). In addition, total dimethylphosphate (DMP) levels were positively associated with children working on farms (β ± SE. = 0.619 ± 0.264, 95%CI = 0.091, 1.147). Importantly, GSH levels among children in the agricultural community were significantly lower than those in the urban community (P < 0.001), but MDA levels did not differ. These results therefore suggest that children can be exposed to OPs both outdoors and indoors. Our results also provide supporting evidence that OP exposure can cause oxidative stress in children. As oxidative stress contributes to several chronic diseases, a good proposed strategy for the future would include measurement of oxidative stress biomarkers among children exposed to OPs as an early warning of chronic diseases.
  [Sapbamrer, R., Hongsibsong, S. and Khacha-Ananda, S. (2020) Urinary organophosphate metabolites and oxidative stress in children living in agricultural and urban communities, Environmental Science and Pollution Research. Available at: https://link.springer.com/article/10.1007/s11356-020-09037-z. ]
• Benchmarking the in Vitro Toxicity and Chemical Composition of Plastic Consumer Products
  

  Abstract

  Plastics are known sources of chemical exposure and few, prominent plastic-associated chemicals, such as bisphenol A and phthalates, have been thoroughly studied. However, a comprehensive characterization of the complex chemical mixtures present in plastics is missing. In this study, we benchmark plastic consumer products, covering eight major polymer types, according to their toxicological and chemical signatures using in vitro bioassays and nontarget high-resolution mass spectrometry. Most (74%) of the 34 plastic extracts contained chemicals triggering at least one end point, including baseline toxicity (62%), oxidative stress (41%), cytotoxicity (32%), estrogenicity (12%), and antiandrogenicity (27%). In total, we detected 1411 features, tentatively identified 260, including monomers, additives, and nonintentionally added substances, and prioritized 27 chemicals. Extracts of polyvinyl chloride (PVC) and polyurethane (PUR) induced the highest toxicity, whereas polyethylene terephthalate (PET) and high-density polyethylene (HDPE) caused no or low toxicity. High baseline toxicity was detected in all “bioplastics” made of polylactic acid (PLA). The toxicities of low-density polyethylene (LDPE), polystyrene (PS), and polypropylene (PP) varied. Our study demonstrates that consumer plastics contain compounds that are toxic in vitro but remain largely unidentified. Since the risk of unknown compounds cannot be assessed, this poses a challenge to manufacturers, public health authorities, and researchers alike. However, we also demonstrate that products not inducing toxicity are already on the market.
  
  [Zimmermann, L. et al. (2019) ‘Benchmarking the in vitro toxicity and chemical composition of plastic consumer products’, Environmental Science & Technology, 53(19), pp. 11467–11477. doi:10.1021/acs.est.9b02293. ]
• Crocin-protected malathion-induced spatial memory deficits by inhibiting TAU protein hyperphosphorylation and antiapoptotic effects
  Organophosphorus compounds are widely used in agriculture. Epidemiological studies propose that pesticide exposure is a risk factor for Alzheimer’s disease (AD), but the mechanisms are unclear. Here, we investigated the impact of malathion exposure on the cognitive ability and the underlying mechanisms in rats. Moreover, we studied whether crocin reduced malathion-induced cognitive and memory loss in rats. Malathion (100 mg/kg) and crocin (10, 20 and 40 m/kg) were administered into the rats once a day for 14 days via i.p. Also vitamin E was used as positive control. Malathion exhibited spatial memory deficits as assessed by Morris water maze (MWM). Malathion increased the latency to reach the platform and decreased time spent and swimming distance of animals in target quadrant in probe trial. These effects were protected by crocin. Malathion exposure induced spatial learning and memory deficits with a simultaneous decrease of PSD93 and TAU hyperphosphorylation at multiple AD-related phosphorylation sites with activation of glycogen synthase kinase-3β (GSK-3β) and inhibition of protein phosphatase-2A (PP2A). Additionally, the elevation of malondialdehyde (MDA), TNF α and IL-6 levels, amelioration of reduced glutathione (GSH) in the hippocampus and reduction of plasma acetylcholinesterase activity were observed upon administration of the malathion. Also, malathion-induced apoptosis in the hippocampus. Crocin or vitamin E improved memory damages and antagonized the effects of malathion. According to the data of this study, crocin mitigated malathion-induced neurological alterations and cognitive impairment by reducing oxidative stress and inflammation, inhibiting TAU protein hyperphosphorylation and antiapoptotic effects.
  [Mohammadzadeh, L. et al. (2019) ‘Crocin-protected malathion-induced spatial memory deficits by inhibiting TAU protein hyperphosphorylation and antiapoptotic effects’, Nutritional Neuroscience, 23(3), pp. 221–236. doi: 10.1080/1028415X.2018.1492772.]
• Deltamethrin exposure induces oxidative stress and affects meiotic maturation in mouse oocyte
  Pyrethroid insecticides are commonly used as insecticides and considered to be less toxic to mammals, but may still impair the reproduction of animals and humans. The aim of this research was to evaluate the tendency of deltamethrin induced oxidative stress and its effects on meiosis, apoptosis and autophagy of mouse oocytes in vitro maturation after deltamethrin exposure. Especially, the maturation rate of oocytes decreased significantly after 14 h exposure of deltamethrin in concentration-dependent manners, which was manifested as abnormal spindle morphology and DNA double strand breaks. Oxidative stress was found in mouse oocytes exposed to deltamethrin, as shown by changes in the expression of CAT and SOD2. Our results also show that deltamethrin affects the quality of oocytes by causing abnormal mitochondrial distribution and by decreasing mitochondrial membrane potential. The apoptosis of oocyte regulated by the expression of Bax and Bcl-2 protein was obviously affected by deltamethrin. Compared with the control group, the expression of key regulatory factors in the autophagy pathway, LC3, Atg12, Atg14, and Beclin, increased in the experimental group. In summary, these results revealed that deltamethrin might inhibit the maturation of mouse oocytes and adversely affect the survival of oocytes.
  [Jia, Z. Z., Zhang, J. W., Zhou, D., Xu, D. Q., & Feng, X. Z. (2019). Deltamethrin exposure induces oxidative stress and affects meiotic maturation in mouse oocyte. Chemosphere, 223, 704–713. https://doi.org/10.1016/j.chemosphere.2019.02.092]
• Gut Inflammation in Association With Pathogenesis of Parkinson’s Disease
  Parkinson’s disease (PD) is a neurodegenerative disease that is generally thought to be caused by multiple factors, including environmental and genetic factors. Emerging evidence suggests that intestinal disturbances, such as constipation, are common non-motor symptoms of PD. Gut inflammation may be closely associated with pathogenesis in PD. This review aims to discuss the cross-talk between gut inflammation and PD pathology initiation and progression. Firstly, we will highlight the studies demonstrating how gut inflammation is related to PD. Secondly, we will analyze how gut inflammation spreads from the gastro-intestine to the brain. Here, we will mainly discuss the neural pathway of pathologic α-syn and the systemic inflammatory routes. Thereafter, we will address how alterations in the brain subsequently lead to dopaminergic neuron degeneration, in which oxidative stress, glutamate excitotoxicity, T cell driven inflammation and cyclooxygenase-2 (COX-2) are involved. We conclude a model of PD triggered by gut inflammation, which provides a new angle to understand the mechanisms of the disease.
  [Chen, Q. Q., Haikal, C., Li, W., & Li, J. Y. (2019). Gut inflammation in association with pathogenesis of Parkinson’s disease. Frontiers in molecular neuroscience, 12, 218. https://www.frontiersin.org/journals/molecular-neuroscience/articles/10.3389/fnmol.2019.00218/full ]
• ROS generation and DNA damage contribute to abamectin-induced cytotoxicity in mouse macrophage cells
  The widespread use of abamectin has recently raised safety concerns as abamectin has yielded various toxicities to non-target organisms. However, the underlying mechanisms of abamectin-induced toxicity are still largely unknown. The present study aimed to investigate the abamectin-induced cytotoxicity in mouse macrophage cells (RAW264.7) and its underlying mechanisms. Abamectin treatment caused oxidative stress as characterized by increased intensity of the ROS indicator. Abamectin also led to DNA damage as demonstrated by increased 8-OHdG/dG ratio in cells even at a relatively low dose (NOAEL). Pretreatment with catalase-PEG, a ROS inhibitor, attenuated abamectin-induced DNA damage, indicating that ROS overproduction should be the reason for abamectin-induced DNA damage. The effects of abamectin on ROS elimination and generation were also investigated, and the results showed that abamectin induced concentration-dependent alteration in the expression and activities of CAT, SOD, GPx enzymes and GSH level (ROS elimination), but had limited effects on the expression and activities of NOX, mitochondrial complex I and III (ROS production) in RAW264.7 cells. Therefore, the effects of abamectin on ROS elimination should be the main reason for abamectin-induced oxidative stress in RAW264.7 cells. Abamectin treatment activated MAPK and ATM/ATR signaling pathways as demonstrated by increased phosphorylation of JNK, ATM and ATR. In addition, inhibiting JNK and ATM/ATR signaling pathways partially rescued the decrease in cell viability, indicating that abamectin-induced ROS overproduction and DNA damage might finally lead to cytotoxicity through JNK and ATM/ATR signaling pathways. These findings should be useful for the more comprehensive assessment of the toxic effects of abamectin.
  [Liang, Y., Dong, B., Pang, N., & Hu, J. (2019). ROS generation and DNA damage contribute to abamectin-induced cytotoxicity in mouse macrophage cells. Chemosphere, 234, 328–337. https://doi.org/10.1016/j.chemosphere.2019.06.031]
• The toxic effects and possible mechanisms of glyphosate on mouse oocytes
  Glyphosate is a high-efficiency, low-toxicity, broad-spectrum herbicide. The residues of glyphosate-based herbicides are frequent pollutants in the environment. However, the effects of glyphosate on oocyte maturation, as well as its possible mechanisms, remain unclear. The present study revealed that mouse oocytes had reduced rates of germinal vesicle breakdown (GVBD) and first polar body extrusion (PBE) after treatment with 500 μM glyphosate. Reactive oxygen species (ROS) were found in mouse oocytes exposed to glyphosate, as shown by changes in the mRNA expression of related antioxidant enzyme genes (cat, sod2, gpx). After 14 h of exposure to glyphosate, metaphase II (MII) mouse oocytes displayed an abnormal spindle morphology and DNA double-strand breaks (DNA-DSBs). Simultaneously, mitochondria showed an aggregated distribution and decreased membrane potential in mouse oocytes exposed to glyphosate. The protein expression levels of apoptosis factors (Bax, Bcl-2) and the mRNA expression levels of apoptosis-related genes (bax, bcl-2, caspase3) were measured by Western blot and qRT-PCR, respectively. Meanwhile, the expression levels of autophagy-related genes (lc3, atg14, mtor) and proteins (LC3, Atg12) were significantly decreased in the glyphosate treatment group compared with the control group. Collectively, our results indicated that glyphosate exposure could interfere with mouse oocyte maturation by generating oxidative stress and early apoptosis.
  [Zhang, J. W., Xu, D. Q., & Feng, X. Z. (2019). The toxic effects and possible mechanisms of glyphosate on mouse oocytes. Chemosphere, 237, 124435. https://doi.org/10.1016/j.chemosphere.2019.124435]
• Effect of imidacloprid on antioxidant status and histopathological changes in ovary and uterus of adult female wistar rats
  Imidacloprid is a neonicotinoid insecticide and has been extensively used as a crop pest and in pet flea control programme. In the present study, the effects of imidacloprid on ovary and uteri tissue was analyzed in adult female Wistar rats at two dose levels (19 and 38 mg/kg/day) administered orally for 10, 20 and 30 days. Effects were compared with respective control animals administered daily with 2% gum acacia. Parameters undertaken were organ weight, levels of cytoplasmic and membrane proteins, oxidative stress parameters viz. activities of SOD, GPx and levels of GSH and MDA and histopathological changes. IMI (38 mg/kg, 30 days) reduced cytoplamic proteins in both ovaries and uteri whereas this dose reduced membrane protein in ovaries only. IMI (38 mg/kg, 20 and 30 days) decreased SOD enzyme in both ovaries and uteri and GSH-Px levels in ovaries only. The GSH-Px levels were also seen with decreased levels in uteri with IMI (38 mg/kg) for 30 days. IMI (38 mg/kg, 20 and 30 days) induces degenerative changes in ovaries of rats. Hence, it is concluded from the present studies that administration of higher doses (38 mg/kg/day) of IMI for 20 and 30 days generated oxidative stress in ovaries and uteri of female rats. 
  [Lohiya, Archana & Kumar, Vinod & Punia, J.S.. (2018). Effect of imidacloprid on antioxidant status and histopathological changes in ovary and uterus of adult female wistar rats. Indian Journal of Animal Research. 10.18805/ijar.B-3613.]
• Environmental concentrations of triclosan activate cellular defence mechanism and generate cytotoxicity on zebrafish (Danio rerio) embryos.
  Triclosan (TCS, 5‑chloro‑2‑(2,4‑dichlorophenoxy) phenol) is becoming a major surface waters pollutant worldwide at concentrations ranging from ng L−1 to μg L−1. Up to now, the adverse effects on aquatic organisms have been investigated at concentrations higher than the environmental ones, and the pathways underlying the observed toxicity are still not completely understood. Therefore, the aim of this study was to investigate the toxic effects of TCS at environmental concentrations on zebrafish embryos up to 120 hours post fertilization (hpf). The experimental design was planned considering both the quantity and the exposure time for the effects on the embryos, exposing them to two different concentrations (0.1 μg L−1, 1 μg L−1) of TCS, for 24 h (from 96 to 120 hpf) and for 120 h (from 0 to 120 hpf). A suite of biomarkers was applied to measure the induction of embryos defence system, the possible increase of oxidative stress and the DNA damage. We measured the activity of glutathione‑S‑transferase (GST), P‑glycoprotein efflux and ethoxyresorufin‑o‑deethylase (EROD), the level of ROS, the oxidative damage through the Protein Carbonyl Content (PCC) and the activity of antioxidant enzymes. The genetic damage was evaluated through DNA Diffusion Assay, Micronucleus test (MN test), and Comet test. The results showed a clear response of embryos defence mechanism, through the induction of P-gp efflux functionality and the activity of detoxifying/antioxidant enzymes, preventing the onset of oxidative damage. Moreover, the significant increase of cell necrosis highlighted a strong cytotoxic potential for TCS. The overall results obtained with environmental concentrations and both exposure time, underline the critical risk associated to the presence of TCS in the aquatic environment.
  [Parenti, CC et al. 2018. Science of the Total Environment 650 (2019): 1752-1758.]
• In vitro genotoxicity assessment of dinitroaniline herbicides pendimethalin and trifluralin.
  Pendimethalin and trifluralin are widely used dinitroaniline herbicides. Both compounds can be found as residue levels in agricultural products. This study was conducted in order to provide necessary information for the risk assessment of pendimethalin and trifluralin. In this study, reactive oxygen species (ROS) levels were measured to examine the potential of both compounds to induce oxidative damage in Chinese hamster lung fibroblast (V79) cells. Also, the genotoxic effects of pendimethalin and trifluralin at the concentration range of 1-500 μM was determined. Single cell gel electrophoresis (comet) and micronucleus assays were used on human peripheral lymphocytes and V79 cells for the genotoxicity assessment. The cell viability of two dinitroaniline herbicides were determined by the use of neutral red uptake assay on V79 cells. IC50 values were determined as 66 μM and 128 μM for pendimethalin and trifluralin, respectively. They significantly increased ROS levels on V79 cells for 1-24 h. Both herbicides significantly induced the DNA damage and showed genotoxicity on lymphocytes and V79 cells. Micronucleus frequency increased significantly after pendimethalin and trifluralin treatment of the lymphocytes and V79 cells. Therefore, we concluded that both of the herbicides induced the genotoxicity through the activation of oxidative stress pathway and chromosomal damage.
  [Kılıç, Z.S., Aydın, S., Bucurgat, Ü.Ü. and Başaran, N., 2018. Food and chemical toxicology, 113, pp.90-98.]
• Markers of genotoxicity and oxidative stress in farmers exposed to pesticides
  The effects of chronic exposure to pesticides can lead to the development of several diseases, including different types of cancer, since the genotoxic and mutagenic capacity of these substances can be observed. The objective of this study is to investigate the relation between the occupational exposure to various pesticides and the presence of DNA damage and oxidative stress. Blood samples from 50 rural workers (41 men and 9 women) exposed to pesticides, 46 controls (20 men and 26 women) from the same city (Antônio Carlos, Santa Catarina state, Brazil) and 29 controls (15 men and 14 women) from another city (Florianópolis, Santa Catarina state, Brazil), were evaluated using the comet assay and the cytokinesis-block micronucleus (CBMN) technique for genetic damage, and the test of thiobarbituric acid reactive substances (TBARS) and catalase (CAT) activity for the oxidative stress. Cholinesterase activities were also determined, but there was no statistical difference among exposed workers and controls. Significant differences were found in DNA damage among groups. The comet assay performed on peripheral blood lymphocytes of these individuals had a significantly higher DNA damage index in the exposed group comparing to controls (p < 0.0001). MNi (p < 0.001), NBUDs (p < 0.005) and NPBs (p < 0.0001) were also found to be significantly higher in the exposed group. The TBARS values were significantly higher comparing to the Florianopolis control group (p < 0.0001). Even though CAT values were higher than controls, there was no statistical difference. Thus, it is concluded that the exposed individuals, participants of this study, are more subject to suffer genetic damage and, consequently, more susceptible to diseases resulting from such damages.
  [Hilgert Jacobsen-Pereira, C., Dos Santos, C. R., Troina Maraslis, F., Pimentel, L., Feijó, A. J. L., Iomara Silva, C., de Medeiros, G. D. S., Costa Zeferino, R., Curi Pedrosa, R., & Weidner Maluf, S. (2018). Markers of genotoxicity and oxidative stress in farmers exposed to pesticides. Ecotoxicology and environmental safety, 148, 177–183. https://doi.org/10.1016/j.ecoenv.2017.10.004]
• Bifenthrin-induced neurotoxicity in rats: involvement of oxidative stress.
  Extensive use of synthetic pyrethroids has resulted in serious human health issues. Induction of oxidative stress is an important mechanism of action of most pesticides including pyrethroids. In the present study, we have elucidated the possible role of oxidative stress in bifenthrin-induced neurotoxicity. Adult male Wistar rats were administered bifenthrin (3.5 and 7 mg per kg body weight p.o.) for 30 days. Behavioral studies were conducted on a set of randomly selected rats from each treatment group after completion of treatment. Neurochemical parameters were assessed 24 h after the last dose was administered. The selected behavioral and neurochemical endpoints were also assessed 15 days after cessation of exposure to reveal whether the neurobehavioral changes produced by bifenthrin were temporary or permanent. Deficits in motor activity, motor incoordination, and cognitive impairment were observed after exposure to bifenthrin. Levels of biogenic amines viz. dopamine (DA) and its metabolites, i.e. 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA), epinephrine (EPN), norepinephrine (NE), and serotonin (5-HT) altered in the frontal cortex, corpus striatum, and hippocampus of bifenthrin-treated rats. A decrease in the activity of acetylcholinesterase (AChE) occurred in all regions of the brain. Both doses of bifenthrin significantly induced lipid peroxidation (LPO) and increased protein carbonyl levels in the frontal cortex, corpus striatum, and hippocampus of rats. The activities of antioxidant enzymes, i.e. catalase, superoxide dismutase, and glutathione peroxidase, were also suppressed in all selected regions of the brain. A trend of recovery was, however, observed in all the behavioral and neurochemical endpoints 15 days after withdrawal of exposure. Oxidative stress seems to play an important role in bifenthrin-induced neurotoxicity. Our study suggests that long-term exposure to these compounds can produce detrimental effects.
  [Syed F, Awasthi KK, Chandravanshi LP, et al 2017. Toxicol Res (Camb). 7(1):48-58.]
• Effects of melatonin in rats in the initial third stage of pregnancy exposed to sub-lethal doses of herbicides.
  Exposure to the herbicides Paraquat (PQ) and Roundup® may cause cell lesions due to an increase in oxidative stress levels in different biological systems, even in the reproductive system. This study evaluated the possible changes in reproductive parameters and hepatic, as well as its prevention by simultaneous application of melatonin.Thirty-five female rats at the age of 3 months were divided into seven groups: three groups exposed to sub-lethal doses of the herbicides PQ (50mg/kg) and Roundup® (500mg/kg) (n=5, G2, G3 and G4); three groups exposed to herbicides and simultaneous treatment with 10mg/kg of Melatonin (n=5, G5, G6 and G7) and control group (n=5, G1) from the first to the seventh day of pregnancy. On the seventh day of pregnancy, the rats were anesthetized and euthanized, followed by laparotomy to remove their reproductive tissues and liver. Body and ovary weights were taken and the number of implantation sites, corpora lutea, preimplantation losses, implantation rates were counted and histopathology of the implantation sites, morphometry of the surface and glandular epithelia of endometrium and hepatic oxidative stress were undertaken.The present study shows the decrease in body and ovary weight, decrease in the number of implantation sites, implantation rate, in the total number of corpora lutea and increase of preimplantation percentages were observed when compared to the G1. The histopathological analysis of the implantation sites showed a disorder of the cytotrophoblast and cell degeneration within the blastocyst cavity in Fig. 4. Morphometry revealed a reduction in surface and glandular epithelia and in the diameter of the endometrial glands (Table 2; p>0.05 ANOVA/Tukey), whereas in liver, serum levels of thiobarbituric acid reactive substances (TBARS) were found to be significantly elevated (Fig. 2; p>0.001; p>0.05 ANOVA/Tukey), and serum level of reduced glutathione (GSH) was significantly lower (Fig. 3; p>0.001 ANOVA/Tukey). However, treatments with melatonin exhibited improvements in reproductive parameters, as well as reduced lesions in the implantation sites  and in serum levels TBARS, serum levels GSH.These results reveal that melatonin is a protective agent against experimentally induced maternal/embryo toxicity with herbicides and favoring normalization of reproductive parameters and hepatic.
  [Almeida LL, Teixeira ÁAC, Soares AF, Cunha FMD, et al. Acta Histochem. 119(3):220-227.]
• Effects of sub-chronic exposure to terbuthylazine on DNA damage, oxidative stress and parent compound/metabolite levels in adult male rats
  Terbuthylazine is a selective pre- and post-emergency chloro-triazine herbicide used for a broad spectrum of weed control. We evaluated the potential of low doses of terbuthylazine to induce oxidative stress and cytogenetic damage in peripheral blood samples of adult male Wistar rats. Following 28-day repeated oral exposure at 0.004 mg/kg b.w./day, 0.4 mg/kg b.w./day and 2.29 mg/kg b.w./day, parameters of lipid peroxidation, total antioxidant capacity, and activities of antioxidant enzymes were measured in blood samples. Alkaline comet assay on leukocytes and erythrocyte micronucleus assay were used to measure DNA damage. In addition, the concentration of terbuthylazine and its metabolite in urine and plasma were determined using high performance liquid chromatography with UV diode-array detector (HPLC-UV-DAD). The fraction of terbuthylazine excreted in urine was negligible and was not found in plasma. Deethylterbuthylazine was only compound detected in plasma samples. Exposure to terbuthylazine did not induce significant lipid peroxidation products. The significant changes in antioxidant enzyme activities and the elevated total antioxidant capacity indicated that terbuthylazine at experimental conditions applied has potential to disturb oxidative/antioxidant balance. Results regarding the alkaline comet assay as well as micronucleated reticulocyte frequency indicated that treatment led to low-level DNA instability. Our results call for further research using other sensitive biomarkers of effect, along with different exposure scenarios.
  [Tariba Lovaković, B., Pizent, A., Kašuba, V., Kopjar, N., Micek, V., Mendaš, G., Dvoršćak, M., Mikolić, A., Milić, M., Žunec, S., Lucić Vrdoljak, A., & Želježić, D. (2017). Effects of sub-chronic exposure to terbuthylazine on DNA damage, oxidative stress and parent compound/metabolite levels in adult male rats. Food and chemical toxicology : an international journal published for the British Industrial Biological Research Association, 108(Pt A), 93–103. https://doi.org/10.1016/j.fct.2017.07.046]
• Oxidative stress and gene expression profiling of cell death pathways in alpha-cypermethrin-treated SH-SY5Y cells
  In this study, we investigated the induction of oxidative stress and apoptosis in human neuroblastoma cell line SH-SY5Y in response to alpha-cypermethrin (α-CYPER) exposure. MTT and LDH assays were carried out to assess the α-CYPER cytotoxicity. The IC50 value for α-CYPER was calculated to be 78.3 ± 2.98 µM for the MTT assay and 71.5 ± 3.94 µM for LDH assay. The pyrethroid α-CYPER (1–100 µM), in a dose-dependent manner, induced a significant increase in lipid peroxides measured as malondialdehyde (MDA) and in the levels of nitric oxide (NO). The neuroprotective role of three antioxidants, melatonin (MEL), Trolox and N-acetylcysteine (NAC) against α-CYPER-induced oxidative stress was examined. Compared to other antioxidants, MEL (1 µM) treatment showed the most effective protection against α-CYPER-induced lipid peroxidation and NO production. The effects of α-CYPER on gene expression profiling of cell death pathway in human neuroblastoma SH-SY5Y cells were also investigated. Of the 84 genes examined (P < 0.001; fold change >1.5), changes in mRNA levels were detected in 39 genes: 36 were up-regulated and 3 were down-regulated. A greater fold change reversion than 3.5-fold was observed on the up-regulated ATP6V1G2, BCL2, CASP9, FAS, GADD45A, SPATA2, SYCP2, ATG7, NFKB1, SNCA, ULK1 and JPH3 genes. The results demonstrated that α-CYPER alters the expression of apoptosis-, autophagy- and necrosis genes as well as induces oxidative stress which may lead to DNA damage. The detailed knowledge of the changes in gene expression obtained will provide a basis for further elucidating the molecular mechanisms of the α-CYPER-induced toxicity.
  [Romero, A., Ramos, E., Ares, I. et al. Oxidative stress and gene expression profiling of cell death pathways in alpha-cypermethrin-treated SH-SY5Y cells. Arch Toxicol 91, 2151–2164 (2017). https://doi.org/10.1007/s00204-016-1864-y]
• Early life exposure to permethrin: a progressive animal model of Parkinson's disease.
  Oxidative stress, alpha-synuclein changes, mitochondrial complex I defects and dopamine loss, observed in the striatum of rats exposed to the pesticide permethrin in early life, could represent neuropathological hallmarks of Parkinson's disease (PD). Nevertheless, an animal model of PD should also fulfill criteria of face and predictive validities. This study was designed to: 1) verify dopaminergic status in the striatum and substantia nigra pars compacta; 2) recognize non-motor symptoms; 3) investigate the time-course development of motor disabilities; 4) assess L-Dopa effectiveness on motor symptoms in rats previously exposed to permethrin in early life. The permethrin-treated group received 34mg/kg daily of permethrin from postnatal day 6 to 21, whereas the age-matched control group was administered with the vehicle only. At adolescent age, the permethrin-treated group showed decreased levels of dopamine in the striatum, loss of dopaminergic neurons in the substantia nigra pars compacta and cognitive impairments. Motor coordination defects appeared at adult age (150days old) in permethrin-treated rats on rotarod and beam walking tasks, whereas no differences between the treated and control groups were detected on the foot print task. Predictive validity was evaluated by testing the ability of L-Dopa (5, 10 or 15mg/kg, os) to restore the postural instability in permethrin-treated rats (150days old) tested in a beam walking task. The results revealed full reversal of motor deficits starting from 10mg/kg of L-Dopa. The overall results indicate that this animal model replicates the progressive, time-dependent nature of the neurodegenerative process in Parkinson's disease.
  [Nasuti C, Brunori G, Eusepi P, Marinelli L, et al. 2016. J Pharmacol Toxicol Methods. 83:80-86.]
• Protective effect of intravenous lipid emulsion treatment on malathion-induced ovarian toxicity in female rats
  Objective: Malathion (MLT) is an organophosphate (OP) pesticide widely used in agriculture and for domestic purposes for several years. Intravenous lipid emulsion (ILE) has been reported to reduce toxicity caused by some lipid soluble agents. The aim of this study was to investigate the possible protective effects of ILE treatment on acute malathion toxicity in ovarian tissue of female rats.

  Materials and methods: Twenty-one adult female Wistar rats (weighted 200-250 g) were divided into three groups; control (corn oil, gavage), MLT (one administration of 100 mg/kg/ by gavage), 20% ILE (one intravenous administration of 3 ml/kg) plus the MLT group. Blood samples were collected for biochemical tests. The ovaries were removed and fixed for histopathological and immunohistochemical analyses. Malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px) were investigated in ovarian tissues. Histopathological and immunohistochemical evaluations were performed through scoring ovarian tissue damage and bax/caspase-3 immunoreactivity, respectively.

  Results: SOD activity decreased in MLT group compared to the control group in tissue samples (p = 0.012). ILE treatment significantly increased SOD activity in MLT+ILE group compared to MLT group in tissue samples (p = 0.017). MLT treatment increased significantly caspase-3 and bax immunoreactivity while ILE decreased bax and caspase-3 immunoreactivity. However, no significant difference was found for MDA levels and GSH-Px activity in both blood and tissue samples and for histopathological results.

  Conclusions: The present study revealed that acute oral MLT administration increased oxidative stress and apoptosis in the rats. ILE treatment partially decreased deleterious effects of MLT. Further controlled animal studies are required to define the role of ILE in acute OP poisonings.
  [Ozsoy, A. Z., Nursal, A. F., Karsli, M. F., Uysal, M., Alici, O., Butun, I., Tas, U., & Delibas, I. B. (2016). Protective effect of intravenous lipid emulsion treatment on malathion-induced ovarian toxicity in female rats. European review for medical and pharmacological sciences, 20(11), 2425–2434.]

• Chlorpyrifos inhibits cell proliferation through ERK1/2 phosphorylation in breast cancer cell lines.
  It has been reported that oxidative stress may be induced by pesticides and it could be the cause of health alteration mediated by pollutants exposure. The present investigation was designed to identify the pathway involved in chlorpyrifos (CPF)-inhibited cell proliferation in MCF-7 and MDA-MB-231 breast cancer cell lines. In addition, authors determined if CPF-induced oxidative stress is related to alterations in antioxidant defense system. The molecular mechanisms underlying in the cell proliferation inhibition produced by the pesticide were also looked at. Study demonstrates that CPF (50 μM) induces redox imbalance altering the antioxidant defense system in breast cancer cells. The main mechanism involved in the inhibition of cell proliferation induced by CPF is an increment of p-ERK1/2 levels mediated by H2O2 in breast cancer cells. Study concluded that ERK1/2 phosphorylation is subsequent to ROS production induced by CPF but not the inverse.
  [Ventura C, Venturino A, Miret N, et al. 2015. Chemosphere. 120:343-50.]
• Combined effects of repeated administration of Bretmont Wipeout (glyphosate) and Ultrazin (atrazine) on testosterone, oxidative stress and sperm quality of Wistar rats.
  The potential toxicity resulting from the possible interactions of the herbicides, Ultrazin (atrazine, ATZ) and Bretmont Wipeout (glyphosate, GLY) is not completely known. This study evaluated reproductive- and hepato-toxicity in rats co-exposed to ATZ and GLY.Six weeks old male rats were exposed by gavage three times per week to ATZ (12.5 mg/kg) or GLY (5 mg/kg) alone or in combination (12.5 mg/kg ATZ + 5 mg/kg GLY).ATZ and GLY impaired sperm quality but GLY has more adverse effect on sperm quality than ATZ. Testosterone level, sperm motility, sperm counts, live/dead ratio and the weight of the epididymis were lower in the GLY group compared to the ATZ group by 57%, 33%, 20%, 22% and 41% and higher by 109%, 76.7%, 39.6%, 32.3% and 100% respectively in the combine-exposure group (ATZ + GLY) compared to the GLY group. Oxidative stress and histopathological changes were also noticeable in the liver but not in the testis of GLY-treated animals, and the observed effects were more remarkable in the GLY group than the ATZ or the combined-exposure group. The combined effects of the active ingredients on testosterone level, sperm count and hepatic malondialdehyde (MDA) levels were also similar as when the commercial formulations were used. Study finds antagonistic interactions between the two toxicants on the toxicity endpoints investigated in this study and these effects are due to the active ingredients of both herbicides in the commercial formulations.
  [Abarikwu SO, Akiri OF, et al. 2015. Toxicol Mech Methods.25(1):70-80.]
• Leydig cell number and sperm production decrease induced by chronic ametryn exposure: a negative impact on animal reproductive health.
  Ametryn is an herbicide used to control broadleaf and grass weeds and its acute and chronic toxicity is expected to be low. Since toxicological data on ametryn is scarce, the aim of this study was to evaluate rat reproductive toxicity. Thirty-six adult male Wistar rats (90 days) were divided into three groups: Co (control) and T1 and T2 exposed to 15 and 30 mg/kg/day of ametryn, respectively, for 56 days. Testicular analysis demonstrated that ametryn decreased sperm number per testis, daily sperm production, and Leydig cell number in both treated groups, although little perceptible morphological change has been observed in seminiferous tubule structure. Lipid peroxidation was higher in group T2, catalase activity decreased in T1 group, superoxide dismutase activity diminished, and a smaller number of sulphydryl groups of total proteins were verified in both exposed groups, suggesting oxidative stress. These results showed negative ametryn influence on the testes and can compromise animal reproductive performance and survival.
  [Dantas TA, Cancian G, Neodini DN, et al. 2015. Environ Sci Pollut Res Int. 22(11):8526-35.]
• Physiological and oxidative stress biomarkers in the freshwater monosex Nile tilapia, Oreochromis niloticus L., exposed to pendimethalin-based herbicide
  Fish are relatively sensitive to changes in their surrounding environment, including increasing pollution. Therefore, the present study was undertaken to evaluate the impact of contamination with the pendimethalin-based herbicide; Stomp® 50% EC (50% pendimethalin as emulsive concentrate) on adults of the monosex Nile tilapia Oreochromis niloticus L. A total of 260 fish with body weights of 90 ± 5.0 g were used in the determination of the 96-h LC50 value and of the impacts of acute exposure to pendimethalin on physiological parameters, and oxidative stress and antioxidant biomarkers. The 96-h median lethal concentration (96-h LC50) value of pendimethalin for monosex Nile tilapia was determined as 4.92 mg/L. Abnormal behavioral responses of the fish and the toxic symptoms of pendimethalin exposure are described. Acute exposure to pendimethalin induced leukocytosis, hyperglobulinemia, and hyperglycemia, but resulted in nonsignificant changes in other hemato-biochemical parameters. Moreover, pendimethalin increased lipid peroxidation (LPO) and decreased levels of reduced glutathione and antioxidant enzymes; superoxide dismutase, catalase, and glutathione reductase in both liver and gill tissues, in a time-dependent manner, with maximum alterations observed in the gills rather than the liver. We conclude that although pendimethalin is moderately toxic, it does not cause hepatorenal toxicity. However, this herbicide pollutant induces major disturbances to the antioxidant system; induction of oxidative stress and LPO is the proposed toxicodynamic pathway for such stress.
  [El-Sayed, Y.S., Samak, D.H., Abou-Ghanema, I.Y. and Soliman, M.K. (2015), Physiological and oxidative stress biomarkers in the freshwater monosex Nile tilapia, Oreochromis niloticus L., exposed to pendimethalin-based herbicide. Environ. Toxicol., 30: 430-438. https://doi.org/10.1002/tox.21919]
• Subacute poisoning of mice with deltamethrin produces memory impairment, reduced locomotor activity, liver damage and changes in blood morphology in the mechanism of oxidative stress
  Background
  Deltamethrin (DEL) is a synthetic pyrethroid (PYR) insecticide, potent neurotoxicant. The current investigation was envisaged to explore behavioral, biochemical and morphologic effects of subacute poisoning with DEL in mice and to find one common mechanism of these changes.
  Methods
  Mice were daily injected ip with different doses of DEL: 8.3, 20.75 or 41.5 mg/kg bw for 28 days. Their memory retention in passive avoidance task (PA), fresh spatial memory in a Y-maze and locomotor activity were measured once weekly. On day 29, blood morphology, alanine transaminase (ALT) activity and creatinine concentration in the blood sera, superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities were measured in the livers and kidneys. Livers were examined with light microscopy.
  Results
  Significant impairment of memory retention was recorded on day 2, 7 and 28 after exposure to DEL. Fresh spatial memory was significantly impaired by the highest dose of DEL on day 1, 14 and 28. Locomotor activity was reduced at every stage of experiment in all the groups exposed to DEL. In the animals exposed to the highest dose of DEL activities of alanine transaminase (ALT) and SOD were elevated, GPx was reduced, lymphocyte infiltrates were detected in the livers and there were changes in blood morphology.
  Conclusion
  The results obtained indicate that liver and bone marrow, apart from the central nervous system (CNS) are damaged in the course of subacute poisoning with DEL. The possible common mechanism of the damage is oxidative stress.
  [Barbara Nieradko-Iwanicka, Andrzej Borzęcki, Subacute poisoning of mice with deltamethrin produces memory impairment, reduced locomotor activity, liver damage and changes in blood morphology in the mechanism of oxidative stress, Pharmacological Reports, Volume 67, Issue 3, 2015, Pages 535-541, ISSN 1734-1140, https://doi.org/10.1016/j.pharep.2014.12.012.]
• Evaluation of the genotoxicity of the pyrethroid insecticide phenothrin
  Phenothrin, a synthetic pyrethroid compound, is widely used to control agricultural and household insects, as well as to eliminate human louse infestation. Toxicity studies on the direct DNA-damaging effect of phenothrin are lacking. We therefore investigated whether phenothrin exposure can lead to increased DNA damage in vitro in human peripheral blood lymphocytes and in human hepatocytes. Genotoxicity was evaluated by means of the comet assay modified with formamidopyrimidine DNA-glycosylase post-treatment for the detection of oxidative base-damage in DNA. We also assessed the cytotoxic potential of this compound by use of combined fluorescence viability staining. Our results show that phenothrin induces statistically significant, dose-dependent DNA damage in the absence of marked cytotoxicity at concentrations higher than 20 μM and 50 μM in human blood peripheral lymphocytes and hepatocytes, respectively. Oxidative DNA damage could also be detected in the two cell types, although this did not reach statistical significance. These findings provide evidence of the DNA-damaging potential of phenothrin and call for additional studies to reveal the genotoxic properties of this pyrethroid. The observations also point at the importance of using caution when considering the use of phenothrin.

  Highlights
  • Genotoxicity of the pyrethroid pesticide phenothrin is tested in in vitro models.

  • Phenothrin induces genotoxic damage in human peripheral lymphocytes and hepatocytes.

  • Oxidative DNA damage exerted by phenothrin can be detected.

  • Use of phenothrin containing products is recommended with caution.
  [Nagy, K. (2014) Evaluation of the genotoxicity of the pyrethroid insecticide phenothrin, Mutation Research/Genetic Toxicology and Environmental Mutagenesis. Available at: https://www.sciencedirect.com/science/article/abs/pii/S138357181400134X. ]

• Toxic Effects of Penoxsulam Herbicide in Two Fish Species Reared in Southern Brazil
  Toxic effects of penoxsulam herbicide on acetylcholinesterase, thiobarbituric acid-reactive substances and protein carbonyl were studied in silver catfish (Rhamdia sp.) and carp (Cyprinus carpio). Acetylcholinesterase activity was inhibited in both brain and muscle tissue, with the inhibition being greater in carp than in silver catfish. The levels of malondialdehyde (MDA), an indicator of lipid peroxidation, decreased in silver catfish brain tissue, but increased in the carp brain. MDA also increased significantly in muscle tissue of silver catfish. The levels of protein carbonyl, another measure of oxidative damage, increased in the brain of both fish species, and in the muscle of carp. However, silver catfish exhibited a decrease in muscle protein carbonyl. It appears that silver catfish may possess better mechanisms of defense against penoxsulam toxicity than carp.
  [Murussi, C.R., Thorstenberg, M.L., Leitemperger, J. et al. Toxic Effects of Penoxsulam Herbicide in Two Fish Species Reared in Southern Brazil. Bull Environ Contam Toxicol 92, 81–84 (2014). https://doi.org/10.1007/s00128-013-1137-x]
• Oxidative stress in carp exposed to quinclorac herbicide under rice field condition
  This study evaluated parameters of oxidative stress and antioxidant profile in fish after herbicide exposure. Cyprinus carpio were exposed to quinclorac (initial concentration 344.60μg/L) for 7, 30, and 90 days under rice field condition. Thiobarbituric acid-reactive substances (TBARS) were evaluated in brain, liver and muscle tissues, and protein carbonyl in liver. Enzymatic parameters such as catalase (CAT) and gluthatione S-transferase (GST) activities also were studied in liver. TBARS levels fluctuated in the brain showing increase in 7 days and decrease in 30 days, while in liver it was observed increase in 7 and 30 days, as well as in muscle after 30 and 90 days. The protein carbonyl was also increased after 30 and 90 days of herbicide exposure. CAT and GST activities were decreased after 30 and 90 days, respectively. The alterations observed suggest that a commercial formulation containing quinclorac causes oxidative damage in different tissues of carp after a long time of exposure. This study pointed out the importance of quinclorac toxicity considering the concentration used in rice fields.
  [Toni, C., Menezes, C., Clasen, B., Leitemperger, J., Pretto, A., Adaime, M. B., Leonardo Martins, M., Zanella, R., & Lucia Loro, V. (2013). Oxidative stress in carp exposed to quinclorac herbicide under rice field condition. Ecotoxicology and environmental safety, 92, 27–31. https://doi.org/10.1016/j.ecoenv.2013.01.028]
• Cytotoxicity and DNA damage of five organophosphorus pesticides mediated by oxidative stress in PC12 cells and protection by vitamin E
  Previous studies have demonstrated that pesticides could induce cytotoxicity and genotoxicity in vivo and in vitro, and that oxidative stress may be an important factor involved. However, investigations comparing the capability of different organophosphorous (OP) compounds to induce cytotoxicity, genotoxicity and oxidative stress are limited. Hence, the aim of this paper was to access the cytotoxic and genotoxic effects of five OPs or metabolites, Acephate (ACE), Methamidophos (MET), Chloramidophos (CHL), Malathion (MAT) and Malaoxon (MAO), and to clarify the role of oxidative stress, using PC12 cells. The results demonstrated that MET, MAT and MAO caused significant inhibition of cell viability and increased DNA damage in PC12 cells at 40 mg L−1. MAO was more toxic than the other OPs. ACE, MET, MAT and MAO increased the levels of intracellular reactive oxygen species (ROS) and malondialdehyde (MDA), and decreased the activity of superoxide dismutase (SOD), catalase (CAT) and glutathione (GSH) at 20 mg L−1 and 40 mg L−1 to different degrees. Pre-treatment with vitamin E(600 μM)caused a significant attenuation in the cytotoxic and genotoxic effect; pre-treatment reversed subsequent OP-induced elevation of peroxidation products and the decline of anti-oxidant enzyme activities. These results indicate that oxidative damage is likely to be an initiating event that contributes to the OP-induced cytotoxicity.
  [Lu, X. T. et al. (2012) ‘Cytotoxicity and DNA damage of five organophosphorus pesticides mediated by oxidative stress in PC12 cells and protection by vitamin E’, Journal of Environmental Science and Health, Part B, 47(5), pp. 445–454. doi: 10.1080/03601234.2012.663312.]
• Correlation of testicular toxicity and oxidative stress induced by chlorpyrifos in rats
  Effect of chlorpyrifos pesticide on testicular oxidative damage was studied in Sprague-Dawley rats at varying doses. At lower doses (5 and 10 mg/kg body weight/30 days), reduction in plasma levels of testosterone and follicular stimulating hormone (FSH) and luteinizing hormone (LH) along with significant shrinkage of seminiferous tubules and drastic changes in germ cells were seen. But these adverse changes of testes were restored with the revival of serum testosterone and FSH and LH at higher doses (20 and 30 mg/kg body weight/30 days). Similarly, levels of testicular lipid peroxidation and diene conjugates were elevated whereas activities of antioxidant enzymes (superoxide dismutase, catalase and glutathione peroxidase), steroidogenic (Δ5, 3β-HSD and Δ5, 17β-HSD) enzymes and angiotensinogen-converting enzyme and glutathione content including lipid–protein content of testes were decreased at low doses. But at higher doses, reductions in level of lipid peroxidation (as revealed by malondialdehyde [MDA] value) and conjugated dienes were found and on the contrary, revivals of testicular antiperoxidative/antioxidant enzymes defense systems, angiotensinogen-converting enzyme (ACE), steroidogenic enzymes, lipid–protein and antioxidant glutathione content were observed. Therefore, the present study indicated from the results that chlorpyrifos had a dual effect at both doses on oxidative stress changes, but at higher doses, the cells were triggering its natural defense mechanism to combat the insult of lower doses of chlorpyrifos and became operative possibly through corrective measure of antioxidant enzymes defense system and pituitary gonadotropins hormones feedback mechanisms on testes.
  [Mandal TK, Das NS. Correlation of testicular toxicity and oxidative stress induced by chlorpyrifos in rats. Human & Experimental Toxicology. 2011;30(10):1529-1539. doi:10.1177/0960327110392400]
• Nigrostriatal neuronal death following chronic dichlorvos exposure: crosstalk between mitochondrial impairments, α synuclein aggregation, oxidative damage and behavioral changes
  Background
  In recent years, several lines of evidence have shown an increase in Parkinson's disease prevalence in rural environments where pesticides are heavily used. Although, the underlying mechanism for neuronal degeneration in sporadic PD remains unknown, mitochondrial dysfunction, oxidative stress and proteasomal dysfunction are proposed as contributing factors. In this study rats were chronically and continuously exposed to the pesticide, dichlorvos to identify the molecular mechanism of nigrostaital neuronal degeneration.

  Result
  Chronic dichlorvos exposure (2.50 mg/kg b.wt.s.c/daily for 12 weeks) caused nigrostriatal dopaminergic degeneration. The degenerative changes were accompanied by a loss of 60-80% of the nigral dopamine neurons and 60-70% reduction in striatal dopamine and tyrosine hydroxylase levels. Dichlorvos exposed animals also showed α -synuclein and ubiquitin positive inclusions along with swollen, dystrophic neurites and mitochondrial abnormalities like decreased complex I&IV activities, increased mitochondrial size, axonal degeneration and presence of electron dense perinuclear cytoplasmic inclusions in the substantia nigra of rats. These animals also showed evidence of oxidative stress, including increased mitochondrial ROS levels, decreased MnSOD activity and increased lipid peroxidation. Measurable impairments in neurobehavioral indices were also observed. Notable exacerbations in motor impairments, open field and catalepsy were also evident in dichlorvos exposed animals.

  Conclusion
  All these findings taken together indicate that chronic dichlorvos exposure may cause nigrostaital neurodegenaration and significant behavioral impairments.
  [BK, B., Bal, A., Kandimalla, R.J. et al. Nigrostriatal neuronal death following chronic dichlorvos exposure: crosstalk between mitochondrial impairments, α synuclein aggregation, oxidative damage and behavioral changes. Mol Brain 3, 35 (2010). https://doi.org/10.1186/1756-6606-3-35]

• Ameliorating the Developmental Neurotoxicity of Chlorpyrifos: A Mechanisms-Based Approach in PC12 Cells
  Background
  Organophosphate developmental neurotoxicity involves multiple mechanisms converging on neural cell replication and differentiation.

  Objectives
  We evaluated mechanisms contributing to the adverse effects of chlorpyrifos (CPF) on DNA synthesis, cell number and size, and cell signaling mediated by adenylyl cyclase (AC) in PC12 cells, a neuronotypic cell line that recapitulates the essential features of developing mammalian neurons.

  Results
  In undifferentiated cells, cholinergic receptor antagonists had little or no protective effect against the antimitotic actions of CPF; however, when nerve growth factor was used to evoke differentiation, the antagonists showed partial protection against deficits in cell loss and alteration in cell size elicited by CPF, but were ineffective in preventing the deterioration of AC signaling. Nicotine, which stimulates nicotinic acetylcholine receptors but also possesses a mixture of prooxidant/antioxidant activity, had adverse effects by itself but also protected undifferentiated cells from the actions of CPF and had mixed additive/protective effects on cell number in differentiating cells. The antioxidant vitamin E also protected both undifferentiated and differentiating cells from many of the adverse effects of CPF but worsened the impact on AC signaling. Theophylline, which prevents the breakdown of cyclic AMP, was the only agent that restored AC signaling to normal or supranormal levels but did so at further cost to cell replication.

  Conclusions
  Our results show definitive contributions of cholinergic hyperstimulation, oxidative stress, and interference with AC signaling in the developmental neurotoxicity of CPF and point to the potential use of this information to design treatments to ameliorate these adverse effects.
  [Slotkin, T.A. et al. (2007) Ameliorating the Developmental Neurotoxicity of Chlorpyrifos: A Mechanisms-Based Approach in PC12 Cells, Environmental Health Perspectives. Available at: https://pmc.ncbi.nlm.nih.gov/articles/PMC1964921/. ]

• Dopaminergic system modulation, behavioral changes, and oxidative stress after neonatal administration of pyrethroids.
  Pyrethroids are a class of insecticides involved in different neurological disorders. They cross the blood-brain barrier and exert their effect on dopaminergic system, contributing to the burden of oxidative stress in Parkinson's disease through several pathways. The aim of this study was to evaluate the effect of neonatal exposition to permethrin and cypermethrin (1/10 of DL(50)) in rats from the eighth to the fifteenth day of life. Open-field studies showed increased spontaneous locomotor activity in the groups treated with permethrin and the one treated with cypermethrin, while a higher number of center entries and time spent in the center was observed for the cypermethrin-treated group. Lower dopamine and higher homovanillic acid levels were measured in the striatum from both treated groups. A reduction of blood glutathione peroxidase content was measured, while no change in blood superoxide dismutase was observed. Carbonyl group formation increased in striatum, but not in erythrocytes. Lipid peroxidation occurred in erythrocytes, but not in striatum. No changes in fluidity at different depths of plasma membrane were measured in striatum or erythrocytes. The activation of monocyte NADPH oxidase by phorbol esters (PMA) shows that superoxide anion production was reduced in the pyrethroid-treated groups compared to the control group. Study suggests that neonatal exposition to permethrin or cypermethrin induces long-lasting effects after developmental exposure giving changes in open-field behaviors, striatal monoamine level, and increased oxidative stress. Although the action of pyrethroids on various target cells is different, a preferential interaction with the extracellular side of plasma membrane proteins can be observed.
  [Nasuti C, Gabbianelli R, Falcioni ML, et al.2007. Toxicology. 229(3):194-205.]
• Impaired mitochondrial energy metabolism and neuronal apoptotic cell death after chronic dichlorvos (OP) exposure in rat brain
  The present study elucidates a possible mechanism by which chronic organophosphate exposure (dichlorvos 6 mg/kg bw, s.c. for 12 weeks) causes neuronal degeneration. Mitochondria, as a primary site of cellular energy generation and oxygen consumption represent itself a likely target for organophosphate poisoning. Therefore, the objective of the current study was planned with an aim to investigate the effect of chronic dichlorvos exposure on mitochondrial calcium uptake, oxidative stress generation and its implication in the induction of neuronal apoptosis in rodent model. Mitochondrial preparation from dichlorvos (DDVP) treated rat brain demonstrated significant increase in mitochondrial Ca2+ uptake (644.2 nmol/mg protein). Our results indicated decreased mitochondrial electron transfer activities of cytochrome oxidase (complex IV) along with altered mitochondrial complex I, and complex II activity, which might have resulted from elevated mitochondrial calcium uptake. The alterations in the mitochondrial calcium uptake and mitochondrial electron transfer enzyme activities in turn might have caused an increase in malondialdehyde, protein carbonyl and 8-hydoxydeoxyguanosine formation as a result of enhanced lipid peroxidation, and as well as protein and mtDNA oxidation. All this could have been because of enhanced oxidative stress, decreased GSH levels and also decreased Mn-SOD activity in the mitochondria isolated from dichlorvos treated rat brain. Thus, chronic organophosphate exposure has the potential to disrupt cellular antioxidant defense system which in turn triggers the release of cytochrome c from mitochondria to cytosol as well as caspase-3 activation in dichlorvos treated rat brain as revealed by immunoblotting experiments. Low-level long-term organophosphate exposure finally resulted in oligonucleosomal DNA fragmentation, a hallmark of apoptosis. These studies provide an evidence of impaired mitochondrial bioenergetics and apoptotic neuronal degeneration after chronic low-level exposure to dichlorvos.
  [Kaur, P., Radotra, B., Minz, R. W., & Gill, K. D. (2007). Impaired mitochondrial energy metabolism and neuronal apoptotic cell death after chronic dichlorvos (OP) exposure in rat brain. Neurotoxicology, 28(6), 1208–1219. https://doi.org/10.1016/j.neuro.2007.08.001]
• A Drosophila model for age-associated changes in sleep:wake cycles
  One of the most consistent behavioral changes that occurs with age in humans is the loss of sleep consolidation. This can be quite disruptive and yet little is known about its underlying basis. To better understand the effects of aging on sleep:wake cycles, we sought to study this problem in Drosophila melanogaster, a powerful system for research on aging and behavior. By assaying flies of different ages as well as monitoring individual flies constantly over the course of their lifetime, we found that the strength of sleep:wake cycles decreased and that sleep became more fragmented with age in Drosophila. These changes in sleep:wake cycles became faster or slower with manipulations of ambient temperature that decreased or increased lifespan, respectively, demonstrating that they are a function of physiological rather than chronological age. The effect of temperature on lifespan was not mediated by changes in overall activity level or sleep amount. Flies treated with the oxidative stress-producing reagent paraquat showed a breakdown of sleep:wake cycles similar to that seen with aging, leading us to propose that the accumulation of oxidative damage with age contributes to the changes in rhythm and sleep. Together, these findings establish Drosophila as a valuable model for studying age-associated sleep fragmentation and breakdown of rhythm strength, and indicate that these changes in sleep:wake cycles are an integral part of the physiological aging process.
  [K. Koh, J.M. Evans, J.C. Hendricks, A. Sehgal, A Drosophila model for age-associated changes in sleep:wake cycles, Proc. Natl. Acad. Sci. U.S.A. 103 (37) 13843-13847, https://doi.org/10.1073/pnas.0605903103 (2006).]
• Toxicological effects of oxyfluorfen on oxidative stress enzymes in tilapia Oreochromis niloticus
  Several environmental pollutants enhance the intracellular formation of reactive oxygen species, and can lead to the damage of macromolecules and a decrease in oxidant defences levels in fish. The effects of the herbicide oxyfluorfen on the activities of antioxidant enzymes such as catalase, superoxide dismutase, glutathione reductase, and glutathione S-transferase were evaluated in freshwater fish Oreochromis niloticus. These were determined in tilapia liver exposed to sublethal concentrations (0.3 and 0.6 mg/L at 7, 14, and 21 days of exposure. This study also analyzed the effects of oxyfluorfen on the total fatty acid profile. The results showed that CAT activity was higher in tilapia exposed to oxyfluorfen at the sampling days, except at the highest concentration after 21 days. Similarly, the enhancing effect of the herbicide was observed on the GR activity. However, its effect was moderate at the highest dose. On the contrary, fish treated with oxyfluorfen at both doses displayed a decrease in the SOD activity. After 7 days of treatment at both concentrations tilapia showed a significant increase in GST levels, although the enzymatic activity decreased at 14 and 21 days of exposition when compared with the control. The major saturated fatty acids measured in tilapia liver were the palmitic acid (C16:0; 17.9%) and stearic acid (C18:0; 8.7%). The exposure to oxyfluorfen caused a significant increase of the oleic acid (C18:1), whereas the amount of nervonic acid (C24:1) increased at all sampling data. The results of the present study should be taken in account when using tilapia as an environmental indicator species in studies of xenobiotic biotransformation and biomarker response, as well as in monitoring programmes.
  [Peixoto, Francisco & Fernandes, Davide & Loureiro dos Santos, Dario & Fontaínhas-Fernandes, Antonio. (2006). Toxicological eVects of oxyXuorfen on oxidative stress enzymes in tilapia Oreochromis niloticus. Pesticide Biochemistry and Physiology. 85. 91-96. 10.1016/j.pestbp.2005.10.007.]
• Biochemical effects of some pesticides on lipid peroxidation and free-radical scavengers
  Oxidative stress was studied in blood samples obtained from lindane, malathion and propoxur poisoning cases admitted to the Guru Teg Bahadur Hospital, Delhi and evaluated for lipid peroxidation, oxygen free radical (OFR) scavenging enzymes, and glutathione (GSH) and related enzymes. Acetylcholine esterase (AChE), gamma glutamyl transpeptidase (GGT) and GSH level were also assayed in lymphocytes. The level of thiobarbituric acid reacting substances and activities of superoxide dismutase, catalase, glutathione peroxidase, glutathione-S-transferase and GGT were increased and GSH level was decreased in pesticide poisoning. Apparently lindane (at the concentration examined) was more potent than malathion and propoxur in producing alteration in lipid peroxidation, GSH related parameters and OFR scavenging enzymes. However, AChE activity and GSH level in lymphocytes of malathion poisoning cases were reduced and GGT activity was enhanced in comparison to control subjects. The present results suggest that OFR scavenging enzymes were induced while combating oxidative stress in a differential manner in organochlorine, organophosphate and carbamate poisoning. Increased lipid peroxidation, coupled with altered levels of GSH and OFR scavenging enzymes in the blood are discussed in the light of oxidative stress.
  [B.D. Banerjee, V. Seth, A. Bhattacharya, S.T. Pasha, A.K. Chakraborty, Biochemical effects of some pesticides on lipid peroxidation and free-radical scavengers, Toxicology Letters, Volume 107, Issues 1–3, 1999, Pages 33-47, ISSN 0378-4274, https://doi.org/10.1016/S0378-4274(99)00029-6.]