Fenvalerate induced hepatic oxidative stress in selenium- and/or iodine-deficient rats

Considering the potential adverse effects of selenium and iodine deficiencies, and frequency of intensive but improper use of insecticides, this study was designed to evaluate the effects of a pyrethroid insecticide, fenvalerate, on the oxidant/antioxidant status of liver using a rat model of iodine and/or selenium deficiency. The study was conducted on eight groups of 3-week old Wistar rats. Iodine and/or selenium deficiency was introduced by feeding the animals with a diet containing <0.005 mg selenium/kg and/or supplying with 1% sodium perchlorate containing drinking water for a period of 7 weeks. Fenvalerate exposure (100 mg/kg/d, i.p., for the last 7 days) in normal rats increased hepatic glutathione peroxidase activity and lipid peroxidation, decreased glutathione content, but did not change the activities of catalase or any of the superoxide dismutase forms; in iodine-deficient animals caused only the elevation of lipid peroxidation; in selenium-deficient animals and in combined iodine/selenium deficiency decreased glutathione peroxidase, increased catalase activities and lipid peroxidation, and decreased all the forms of superoxide dismutase activity only in combined deficiency. These results suggested that fenvalerate is an oxidant stress inducer in rat liver, and its potential effects on pro-oxidant/antioxidant balance may also be important for human populations, particularly with iodine and/or selenium deficiencies.