Modulating effect of glutathione (GSH) on 2,4-dichlorophenoxyacetic acid (2,4-D) toxicity.

2,4-dichlorophenoxyacetic acid (2,4-D) is a chlorinated aromatic hydrocarbon herbicide and one of the most widely used herbicides globally. Due to the intensive use of 2,4-D, mainly in agriculture and horticulture, significant amounts of the compound and its metabolites are released into the environment, surface water and soil, posing a serious threat to human health. Scientific studies have shown a positive relationship between 2,4-D exposure and the risk of lymphatic system and prostate cancers. The harmful effects of pesticides and their metabolites on human health can be mitigated by consuming products rich in natural antioxidants, such as glutathione (GSH). This study aimed to elucidate the mechanisms underlying toxicity and genotoxicity of 2,4-D and evaluate the impact of GHS supplementation on mitigating these adverse effects. The toxicity of 2,4-D at the concentrations of 100, 10, 1, 0.1, and 0.01 mg/L was determined by antimicrobial activity against Enterobacter hormaechei and Candida albicans. In contrast, genotoxicity was determined by the level of induction of the genotoxin-sensitive recA promoter in E. coli RFM443 recA:luxCDABE biosensor strain. Synthesis of reactive oxygen species (ROS) in the E. coli strainleads to the oxidative stress response. Moreover, the estrogenic/androgenic effects of 2,4-D were evaluated by yeast estrogen (YES) and androgen (YAS) screen assay using the genetically modified S. cerevisiae strain at various concentrations (100, 10, 1, 0.1, 0.01, 0.001, 0.0001, and 0.00001 mg/L). Finally, the effect of 2,4-D mixtures with GSH at a concentration of 1 mg/L on mitigating its toxic and genotoxic activity was investigated. In the mixtures, the concentration of GSH was lower than the physiological concentration in the cells, and it was selected experimentally to obtain satisfactory results. The experiment was conducted in three independent series, with at least three repetitions of each result (n = 3). Results showed that 2,4-D in the range of applied concentrations exerted a toxic effect on E. homaechei and C. albicans strains and a genotoxic effect in E. coli recA:luxCDABE biosensor strain. Analysis of ROS synthesis values in the E. coli strain showed an increase in this parameter following exposure to the tested 2,4-D concentrations. In the YES and YAS bioassays performed for 2,4-D, we did not detect the ability to stimulate the estrogen/androgen receptor. In mixtures of 2,4-D, a significant (p = 0.05) reduction effect on the toxicity, above 7% for E. hormaechei and above 16% for C. albicans and genotoxicity, by more than 44% of the herbicide was detected after the addition of glutathione This indicating that GSH taken up with food or in the form of supplements can mitigate the adverse effects of 2,4-D in living cells and protect cells from cancer induction. The results confirmed the validity of the hypothesis that oxidative stress induction is a molecular mechanism of 2,4-D toxicity and genotoxicity. Given the significant environmental and food pollution from pesticides and the link between human exposure and cancer induction, proper dietary choice and consumption of foods rich in glutathione are essential in cancer prevention.