effects of vitamin c on paraoxonase1 arylesterase activity in rats exposed to arsenic

background: arsenic as an environmental toxicant is able to induced oxidative stress. the present study aimed to evaluate of vitamin c supplementation on the paraoxonase1 (pon1) arylesterase activity (responsible for hydrolysing lipid-peroxides) in rat exposed to arsenic. methods: the study was conducted in the faculty of veterinary medicine, tabriz islamic azad university, tabriz, iran in 20015. thirty-two adult male rats weighing 200-350 g were randomly divided into 4 groups: group i (normal healthy rat), group ii [treated with sodium arsenite (100 ppm in drinking water)], group iii [treated with vitamin c supplementation (200 mg/kg via gavage)] group iv (treated with sodium arsenite and vitamin c 100 ppm and 200 mg/kg respectively). results: vitamin c supplementation increased paraoxonase1 (pon1) arylesterase activity (p<0.05) but had no significant effect on serum levels of hdl, triglyceride and cholesterol. conclusion: pon1 arylesterase activity is independent of changes in hdl and lipid profile, and vitamin c with different mechanisms such as radical scavenging activity and reduction of oxidative stress leads to increased activity of paraoxonase.