skip to Main Content

Bibliography Tag: oxidative stress

Jasper et al., 2012

Jasper, R., Locatelli, G. O., Pilati, C., & Locatelli, C., “Evaluation of biochemical, hematological and oxidative parameters in mice exposed to the herbicide glyphosate-Roundup(®),” Interdisciplinary Toxicology, 2012, 5(3), 133-140. DOI: 10.2478/v10102-012-0022-5.


We evaluated the toxicity of hepatic, hematological, and oxidative effects of glyphosate-Roundup® on male and female albino Swiss mice. The animals were treated orally with either 50 or 500 mg/kg body weight of the herbicide, on a daily basis for a period of 15 days. Distilled water was used as control treatment. Samples of blood and hepatic tissue were collected at the end of the treatment. Hepatotoxicity was monitored by quantitative analysis of the serum enzymes ALT, AST, and γ-GT and renal toxicity by urea and creatinine. We also investigated liver tissues histopathologically. Alterations of hematological parameters were monitored by RBC, WBC, hemoglobin, hematocrit, MCV, MCH, and MCHC. TBARS (thiobarbituric acid reactive substances) and NPSH (non-protein thiols) were analyzed in the liver to assess oxidative damage. Significant increases in the levels of hepatic enzymes (ALT, AST, and γ-GT) were observed for both herbicide treatments, but no considerable differences were found by histological analysis. The hematological parameters showed significant alterations (500 mg/kg body weight) with reductions of RBC, hematocrit, and hemoglobin, together with a significant increase of MCV, in both sexes of mice. In males, there was an important increase in lipid peroxidation at both dosage levels, together with an NPSH decrease in the hepatic tissue, whereas in females significant changes in these parameters were observed only at the higher dose rate. The results of this study indicate that glyphosate-Roundup® can promote hematological and hepatic alterations, even at subacute exposure, which could be related to the induction of reactive oxygen species. FULL TEXT

Cattani et al., 2017

Cattani, D., Cesconetto, P. A., Tavares, M. K., Parisotto, E. B., De Oliveira, P. A., Rieg, C. E. H., Leite, M. C., Prediger, R. D. S., Wendt, N. C., Razzera, G., Filho, D. W., & Zamoner, A., “Developmental exposure to glyphosate-based herbicide and depressive-like behavior in adult offspring: Implication of glutamate excitotoxicity and oxidative stress,” Toxicology, 2017, 387, 67-80. DOI: 10.1016/j.tox.2017.06.001.


We have previously demonstrated that maternal exposure to glyphosate-based herbicide (GBH) leads to glutamate excitotoxicity in 15-day-old rat hippocampus. The present study was conducted in order to investigate the effects of subchronic exposure to GBH on some neurochemical and behavioral parameters in immature and adult offspring. Rats were exposed to 1% GBH in drinking water (corresponding to 0.36% of glyphosate) from gestational day 5 until postnatal day (PND)-15 or PND60. Results showed that GBH exposure during both prenatal and postnatal periods causes oxidative stress, affects cholinergic and glutamatergic neurotransmission in offspring hippocampus from immature and adult rats. The subchronic exposure to the pesticide decreased L-[(14)C]-glutamate uptake and increased (45)Ca(2+) influx in 60-day-old rat hippocampus, suggesting a persistent glutamate excitotoxicity from developmental period (PND15) to adulthood (PND60). Moreover, GBH exposure alters the serum levels of the astrocytic protein S100B. The effects of GBH exposure were associated with oxidative stress and depressive-like behavior in offspring on PND60, as demonstrated by the prolonged immobility time and decreased time of climbing observed in forced swimming test. The mechanisms underlying the GBH-induced neurotoxicity involve the NMDA receptor activation, impairment of cholinergic transmission, astrocyte dysfunction, ERK1/2 overactivation, decreased p65 NF-kappaB phosphorylation, which are associated with oxidative stress and glutamate excitotoxicity. These neurochemical events may contribute, at least in part, to the depressive-like behavior observed in adult offspring. FULL TEXT

Rice et al., 2018

Rice, J.R., Dunlap, P., Ramaiahgari, S., Ferguson, S., Smith-Roe, S.L., & DeVito, M., “Poster: Effects of Glyphosate and its Formulations on Markers of Oxidative Stress and Cell Viability in HepaRG and HaCaT Cell Lines, 2018, Presented at the Society of Toxicology Conference.


Glyphosate (GLY) is the active ingredient found in herbicide formulations worldwide. GLY is toxic to plants by disrupting the shikimate amino acid synthesis pathway. The present day intensive use of GLY began with the introduction of GLY-resistant crops in the late 1990s. Although GLY has a low toxicity profile for humans and mammals, conflicting reports exist as to whether it poses a cancer risk for humans. The USEPA and European regulatory agencies have described GLY as unlikely to pose a carcinogenic hazard to humans. However, the International Agency for Research on Cancer (IARC) has classified GLY as “probably carcinogenic to humans”.

IARC proposed that oxidative stress may be a mechanism by which GLY could potentially cause cancer. To address this hypothesis, we are testing GLY in human cell lines using several assays that detect reactive oxygen species (ROS) or their effects. Studies were designed to compare the point of departure for the effects of GLY on cell viability (CellTiter-Glo assay) to the point of departure for effects in oxidative damage assays. We also directly compared the effects of GLY versus GLY salts, as well as GLY and adjunct active ingredients versus formulations. We used a high content, 384-well plate approach to generate extensive dose-response curves for multiple comparisons.

Assays (CellTiter-Glo, ROS-Glo, and JC10) were performed after 1 or 24 h of exposure to test articles. GLY and GLY isopropylamine decreased cell viability and altered mitochondrial membrane potential (MMP) at ≥ 10 mM, but did not affect ROS production. The formulations were more potent than GLY alone. Cell viability and MMP were significantly altered at 1 h by the formulations. Based on GLY concentrations, these mixtures were over 1000x more potent than GLY alone. In contrast to the robust induction of ROS by positive controls at both time points, formulations had no effect on ROS at 1 h and showed a marginal increase in ROS at 24 h. These data suggest that GLY does not induce oxidative stress. In addition, the formulations marginally increased oxidative stress only after significant loss of cell viability. The results were very similar for both HepaRG and HaCaT cell lines, suggesting that xenobiotic metabolism has little impact on cell viability and oxidative stress induced by these chemicals. FULL TEXT

Milic et al., 2018

Milic, Mirta, Zunec, Suzana, Micek, Vedran, Kasuba, Vilena, Mikolic, Anja, Lovakovic, Blanka Tariba, Semren, Tanja Zivkovic, Pavicic, Ivan, Cermak, Ana Marija Marjanovic, Pizent, Alica, Vrdoljak, Ana Lucic, Valencia-Quintana, Rafael, Sanchez-Alarcon, Juana, & Zeljezic, Davor, “Oxidative stress, cholinesterase activity, and DNA damage in the liver, whole blood, and plasma of Wistar rats following a 28-day exposure to glyphosate,” Archives of Industrial Hygiene and Toxicology, 2018, 69(2), 154-168. DOI: 10.2478/aiht-2018-69-3114.


In this 28 day-study, we evaluated the effects of herbicide glyphosate administered by gavage to Wistar rats at daily doses equivalent to 0.1 of the acceptable operator exposure level (AOEL), 0.5 of the consumer acceptable daily intake (ADI), 1.75 (corresponding to the chronic population-adjusted dose, cPAD), and 10 mg kg-1 body weight (bw) (corresponding to 100 times the AOEL). At the end of each treatment, the body and liver weights were measured and compared with their baseline values. DNA damage in leukocytes and liver tissue was estimated with the alkaline comet assay. Oxidative stress was evaluated using a battery of endpoints to establish lipid peroxidation via thiobarbituric reactive substances (TBARS) level, level of reactive oxygen species (ROS), glutathione (GSH) level, and the activity of glutathione peroxidase (GSH-Px). Total cholinesterase activity and the activities of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) were also measured. The exposed animals gained less weight than control. Treatment resulted in significantly higher primary DNA damage in the liver cells and leukocytes. Glyphosate exposure significantly lowered TBARS in the liver of the AOEL, ADI, and cPAD groups, and in plasma in the AOEL and cPAD group. AChE was inhibited with all treatments, but the AOEL and ADI groups significantly differed from control. Total ChE and plasma/liver ROS/GSH levels did not significantly differ from control, except for the 35 % decrease in ChE in the AOEL and ADI groups and a significant drop in liver GSH in the cPAD and 100xAOEL groups. AOEL and ADI blood GSH-Px activity dropped significantly, but in the liver it significantly increased in the ADI, cPAD, and 100xAOEL groups vs. control. All these findings show that even exposure to low glyphosate levels can have serious adverse effects and points to a need to change the approach to risk assessment of low-level chronic/sub-chronic glyphosate exposure, where oxidative stress is not necessarily related to the genetic damage and AChE inhibition. FULL TEXT

Kasuba et al., 2018

Kasuba, Vilena, Milic, Mirta, Rozgaj, Ruzica, Kopjar, Nevenka, Mladinic, Marin, Zunec, Suzana, Vrdoljak, Ana Lucic, Pavicic, Ivan, Cermak, Ana Marija Marjanovic, Pizent, Alica, Lovakovic, Blanka Tariba, & Zeljezic, Davor, “Effects of low doses of glyphosate on DNA damage, cell proliferation and oxidative stress in the HepG2 cell line,” Environmental Science and Pollution Research, 2017, 24(23), 19267-19281. DOI: 10.1007/s11356-017-9438-y.


We studied the toxic effects of glyphosate in vitro on HepG2 cells exposed for 4 and 24 h to low glyphosate concentrations likely to be encountered in occupational and residential exposures [the acceptable daily intake (ADI; 0.5 μg/mL), residential exposure level (REL; 2.91 μg/mL) and occupational exposure level (OEL; 3.5 μg/mL)]. The assessments were performed using biomarkers of oxidative stress, CCK-8 colorimetric assay for cell proliferation, alkaline comet assay and cytokinesis-block micronucleus (CBMN) cytome assay. The results obtained indicated effects on cell proliferation, both at 4 and 24 h. The levels of primary DNA damage after 4-h exposure were lower in treated vs. control samples, but were not significantly changed after 24 h. Using the CBMN assay, we found a significantly higher number of MN and nuclear buds at ADI and REL after 4 h and a lower number of MN after 24 h. The obtained results revealed significant oxidative damage. Four-hour exposure resulted in significant decrease at ADI [lipid peroxidation and glutathione peroxidase (GSH-Px)] and OEL [lipid peroxidation and level of total antioxidant capacity (TAC)], and 24-h exposure in significant decrease at OEL (TAC and GSH-Px). No significant effects were observed for the level of reactive oxygen species (ROS) and glutathione (GSH) for both treatment, and for 24 h for lipid peroxidation. Taken together, the elevated levels of cytogenetic damage found by the CBMN assay and the mechanisms of primary DNA damage should be further clarified, considering that the comet assay results indicate possible cross-linking or DNA adduct formation.

Hong et al., 2018

Hong, Y., Yang, X., Huang, Y., Yan, G., & Cheng, Y., “Assessment of the oxidative and genotoxic effects of the glyphosate-based herbicide Roundup on the freshwater shrimp, Macrobrachium nipponensis,” Chemosphere, 2018, 210, 896-906. DOI: 10.1016/j.chemosphere.2018.07.069.


In the present study, an acute toxic test was performed to assess the oxidative stress and genotoxic effects of the herbicide on the freshwater shrimp Macrobrachium nipponensis. The results showed that the 48-h and 96-h LC50 values of Roundup to M. nipponensis were 57.684mg/L and 11.237mg/L, respectively. For further investigation, the shrimps were exposed to sublethal concentrations of 0.35, 0.70, 1.40, 2.80 and 5.60mg/L for 96h. A significant decrease in total haemocytes count (THC) was observed at concentration of 5.60mg/L throughout the experiment. The level of superoxide dismutase (SOD), catalase (CAT) and total antioxidant capacity (T-AOC) in all the treatments decreased in a dose- and time-dependent manner except for the concentration group of 0.35mg/L. The malondialdehyde (MDA), hydrogen peroxide (H2O2) and protein carbonyl in serum increased significantly at concentrations of 2.80mg/L and 5.60mg/L. A significant decrease in acetylcholinesterase (AChE) activity was observed at each concentration (P0.05). In addition, the micronucleus (MN) frequency of haemocytes significantly increased (P0.05) at concentrations of 1.40, 2.80 and 5.60mg/L, whereas the comet ratio and %DNA in the tails exhibited a clear time- and dose-dependent response during the exposure. The analysis of the integrated biomarker response (IBR) showed the induction of oxidative stress biomarkers and the inhibition of antioxidants, and this dose-dependent relation suggests the sensitivity and availability of all the biomarkers. These results revealed that Roundup had a prominent toxic effect on M. nipponensis based on the antioxidative response inhibition and genotoxicity.

DeVito, 2017

DeVito, Michael, “Update on NTP Studies of Glyphosate,” Presented at the National Toxicology Program (NTP) Board of Scientific Counselors Meeting, December 7-8, 2017.


Not available.  FULL TEXT

Bailey et al., 2018

Bailey, D. C., Todt, C. E., Burchfield, S. L., Pressley, A. S., Denney, R. D., Snapp, I. B., Negga, R., Traynor, W. L., & Fitsanakis, V. A., “Chronic exposure to a glyphosate-containing pesticide leads to mitochondrial dysfunction and increased reactive oxygen species production in Caenorhabditis elegans,” Environmental Toxicology and Pharmacology, 2048, 57, 46-52. DOI: 10.1016/j.etap.2017.11.005.


Glyphosate-containing herbicides are among the most widely-used in the world. Although glyphosate itself is relatively non-toxic, growing evidence suggests that commercial herbicide formulations may lead to increased oxidative stress and mitochondrial inhibition. In order to assess these mechanisms in vivo, we chronically (24h) exposed Caenorhabditis elegans to various concentrations of the glyphosate-containing herbicide TouchDown (TD). Following TD exposure, we evaluated the function of specific mitochondrial electron transport chain complexes. Initial oxygen consumption studies demonstrated inhibition in mid- and high-TD concentration treatment groups compared to controls. Results from tetramethylrhodamine ethyl ester and ATP assays indicated reductions in the proton gradient and ATP levels, respectively. Additional studies were designed to determine whether TD exposure resulted in increased reactive oxygen species (ROS) production. Data from hydrogen peroxide, but not superoxide or hydroxyl radical, assays showed statistically significant increases in this specific ROS. Taken together, these data indicate that exposure of Caenorhabditis elegans to TD leads to mitochondrial inhibition and hydrogen peroxide production. FULL TEXT

Shaw, 2017

William Shaw, PhD, “Elevated Urinary Glyphosate and Clostridia Metabolites With Altered Dopamine Metabolism in Triplets With Autistic Spectrum Disorder or Suspected Seizure Disorder: A Case Study,” Integrative Medicine, 2017, 16:1.

CONTEXT: Autism is a neurodevelopmental disorder for which a number of genetic, environmental, and nutritional causes have been proposed. Glyphosate is used widely as a crop desiccant and as an herbicide in fields of genetically modified foods that are glyphosate resistant. Several researchers have proposed that it may be a cause of autism, based on epidemiological data that correlates increased usage of glyphosate with an increased autism rate.

OBJECTIVE:  The current study was intended to determine if excessive glyphosate was present in the triplets and their parents and to evaluate biochemical findings for the family to determine the potential effects of its presence.

DESIGN: The author performed a case study with the cooperation of the parents and the attending physician.

SETTING: The study took place at The Great Plains Laboratory, Inc (Lenexa, KS, USA).

PARTICIPANTS: Participants were triplets, 2 male children and 1 female, and their parents. The 2 male children had autism, whereas the female had a possible seizure disorder. All 3 had elevated urinary glyphosate, and all of the triplets and their mother had elevated values of succinic acid or tiglylglycine, which are indicators of mitochondrial dysfunction.

The participants received a diet of organic food only.

The study performed organic acids, glyphosate, toxic chemicals and tiglylglycine, and creatinine testing of the participants’ urine.

The 2 male triplets with autism had abnormalities on at least 1 organic acids test, including elevated phenolic compounds such as 4-cresol, 3-[3-hydroxyphenyl]-3-hydroxypropionic acid and 4-hydroxyphenylacetic acid, which have been previously associated with Clostridia bacteria and autism. The female, who was suspected of having a seizure disorder but not autism, did not have elevated phenolic compounds but did have a significantly elevated value of the metabolite tiglylglycine, a marker for mitochondrial dysfunction and/or mutations. One male triplet was retested postintervention and was found to have a markedly lower amount of glyphosate in his urine.

The pattern of metabolites in the urine samples of the males with autism are consistent with a recent theory of autism that connects widespread glyphosate use with alteration of animal and human gastrointestinal flora. That theory is that the normally beneficial bacteria species that are sensitive to glyphosate are diminished and harmful bacteria species, such as Clostridia, that are insensitive to glyphosate, are increased following exposure to glyphosate. Excessive dopamine, caused by inhibition of dopamine-beta-hydroxylase by Clostridia metabolites, in turn, produces oxidative species that damage neuronal Krebs cycle enzymes, neuronal mitochondria, and neuronal structural elements such as the neurofibrils.  FULL TEXT

Lerro et al., 2017

Catherine C. Lerro, Laura E. Beane Freeman, Lützen Portengen, Daehee Kang, Kyoungho Lee, Aaron Blair, Charles F. Lynch, Berit Bakke, Anneclaire J. De Roos, and Roel C.H. Vermeulen, “A longitudinal study of atrazine and 2,4-D exposure and oxidative stress markers among Iowa corn farmers,” Environmental and Molecular Mutagenesis, 2017, 58, DOI: 10.1002/em.22069


Reactive oxygen species, potentially formed through environmental exposures, can overwhelm an organism’s antioxidant capabilities resulting in oxidative stress. Long-term oxidative stress is linked with chronic diseases. Pesticide exposures have been shown to cause oxidative stress in vivo. We utilized a longitudinal study of corn farmers and non-farming controls in Iowa to examine the impact of exposure to the widely used herbicides atrazine and 2,4-dichlorophenoxyacetic acid (2,4-D) on markers of oxidative stress. 225 urine samples were collected during five agricultural time periods (pre-planting, planting, growing, harvest, off-season) for 30 farmers who applied pesticides occupationally and 10 controls who did not; all were non-smoking men ages 40–60. Atrazine mercapturate (atrazine metabolite), 2,4-D, and oxidative stress markers (malondialdehyde [MDA], 8-hydroxy-2′-deoxyguanosine [8-OHdG], and 8-isoprostaglandin-F [8-isoPGF]) were measured in urine. We calculated β estimates and 95% confidence intervals (95%CI) for each pesticide-oxidative stress marker combination using multivariate linear mixed-effect models for repeated measures. Farmers had higher urinary atrazine mercapturate and 2,4-D levels compared to controls. In regression models, after natural log transformation, 2,4-D was associated with elevated levels of 8-OHdG (β=0.066, 95%CI=0.008–0.124) and 8-isoPGF (β=0.088, 95%CI=0.004–0.172). 2,4-D may be associated with oxidative stress because of modest increases in 8-OHdG, a marker of oxidative DNA damage, and 8-isoPGF, a product of lipoprotein peroxidation, with recent 2,4-D exposure. Future studies should investigate the role of 2,4-D-induced oxidative stress in the pathogenesis of human diseases.  FULL TEXT

Back To Top