Redox imbalance in rat tissues exposed with organophosphate pesticides and therapeutic potential of antioxidant vitamins.

Organophosphate pesticides are among the most widely used synthetic chemicals for controlling domestic and agricultural pests. Present study was aimed to evaluate the potential of chlorpyrifos, parathion and malathion, to disturb glutathione homeostasis in rat tissues and to find out whether the pre-feeding of antioxidant vitamins has some ameliorating effect on the pesticide-induced alterations. The results showed that these pesticides, alone or in combination, caused decrease in the levels of GSH and the corresponding increase in the levels of GSSG, decreasing the GSH/GSSG ratio. The results also showed NADPH/NADP(+) and NADH/NAD(+) ratios were also decreased in the rat tissues on pesticide exposure. These pesticides, alone or in combination, caused increase in the activities of glutathione reductase and glucose-6-phosphate dehydrogenase in all the rat tissues studied. The findings show that these pesticides generate oxidative stress and prior feeding of mixture of antioxidant vitamins tend to reduce the toxicities of these pesticides.