Antioxidants and lipid peroxidation status in diabetic patients with and without complications.

BACKGROUND Oxidative stress is involved in the pathophysiology of diabetes mellitus. METHODS In the present study, 68 patients with type 2 diabetes mellitus and 31 clinically healthy individuals were evaluated. The patients were divided into two groups. Group 1 included 29 patients without diabetic complications and group 2 consisted of 39 patients with diabetic complications. Erythrocyte glutathione, superoxide dismutase, and thiobarbituric acid-reactive substance levels as well as plasma antioxidant vitamins C and E, and serum total glutathione-S-transferase, ceruloplasmin, and protein thiols were estimated by using spectro-photometer. RESULTS A significant decrease of erythrocyte glutathione was observed in group 1 when compared with the controls. Thiols decreased in group 2. An increase in glutathione-S-transferase, ceruloplasmin, superoxide dismutase, and vitamins C and E levels was noted in patients with diabetes mellitus. Thiobarbituric acid-reactive substance levels decreased in group 1 but increased in group 2 when compared with the controls. CONCLUSION In the present study, tendency of most of the antioxidants to rise in diabetes could probably be due to an adaptive response to the pro-oxidant milieu of the diabetic state. Hence, we suggest that supplementation with dietary antioxidants especially antioxidant vitamins accompanied by change in lifestyle might help to reduce damage brought about by free radical toxicity in diabetes mellitus.