Dietary exposure to continuous small doses of α-cypermethrin in the presence or absence of dietary curcumin does not induce oxidative stress in male Wistar rats.

α-Cypermethrin is a widely used insecticide and, at high doses, induces oxidative stress in mammals. Curcumin is an antioxidant phytochemical commonly used for food coloring and flavoring. We aimed to investigate the effects of continuous dietary exposure to low doses of α-cypermethrin, as is the case in exposed humans, on oxidative stress and its potential prevention by dietary curcumin. Four groups of ten male Wistar rats were ad libitum-fed a control diet or identical diets fortified with α-cypermethrin (350 mg/kg diet), curcumin (1000 mg/kg diet), or α-cypermethrin and curcumin (350 and 1000 mg/kg diet, respectively) for 7 weeks. α-Cypermethrin accumulated in adipose tissues and was detectable in kidney, liver, and brains. Dietary α-cypermethrin did not alter concentrations of malondialdehyde, ascorbic and uric acid, retinol, liver damage markers, or the activities of CAT and SOD, but reduced vitamin E in blood. α-Cypermethrin did not affect malondialdehyde or reduced glutathione concentrations in any of the tissues, but significantly increased glutathione disulfide in kidney and subcutaneous adipose tissue. In conclusion, dietary exposure to small doses of α-cypermethrin did not induce oxidative stress in rats and may be less toxic than exposure to comparable quantities administered as single high doses by gastric intubation.