Cytotoxic effects of acephate, ethoprophos, and monocrotophos in CHO-K1 cells

This work evaluates the cytotoxicity of acephate, ethoprophos, and monocrotophos in the Chinese hamster ovary cell line. The neutral red incorporation (NRI), total cellular protein (TCP) content, and methyl tetrazolium (MTT) assays were followed to estimate the midpoint cytotoxicity values, NRI50, TCP50, and MTT50, respectively. The targeted cells were exposed to the tested pesticides in the presence and absence of fetal calf serum. The effects of the sublethal concentration (NRI25) on glutathione S-transferase, glutathione reductase, glutathione peroxidase, and total glutathione content have been evaluated. In addition, the ameliorative effects of extracellular reduced glutathione (GSH, 1 mM), vitamin C (70 mu M), and vitamin E (30 mu M) were investigated. The exposure period and protein content in the culture medium affected the cytotoxicity of the tested pesticides. Unexpectedly, acephate showed the least MTT50 value, 56.6 mu M. The tested antioxidants caused different and significant effects on the components of the glutathione redox cycle.