The effect of exercise on brain antioxidant status of diabetic rats

Background: To investigate the effect of exercise on brain antioxidant status of diabetic rats. Methods: Wistar rats were divided into four groups: Control (C), exercise (CE), diabetic (D), and diabetic+exercise (DE). Diabetes was induced by single administration of streptozotocin (60 mg/kg). We used an aerobic exercise program for 8 weeks of CE and DE rats. After the end of the experimental period, Cu, Zn-superoxide dismutase (Cu, Zn-SOD), catalase (CAT), glutathione peroxidase (GSH-Px), xanthine dehydrogenase (XDH) and xanthine oxidase (XO) activities and thiobarbituric acid reactive substances (TBARS) levels of brain were measured. Results: Diabetes caused significant reduction of brain Cu, Zn-SOD and GSH-Px activities in the D and DE groups. CAT activity was decreased only in the D group. Exercise did not alter CAT activity of brain, whereas markedly incrased Cu, Zn-SOD activity in the DE group. In contrast to diabetes-related decrease in the activity of Cu, Zn-SOD, increase in the XO and GSH-Px activities were observed in the DE group compared with the D group. XDH activity was significantly reduced in two exercise groups according to the control rats, but the decrease was not accompanied with the activity of XO elevation in all groups. Increase in the XO activity and decrease in the XDH activity in the DE rats have revealed that diabetes and exercise have potentially effect in free radical production. On the other hand, TBARS levels were found to be elevated in all diabetic animals. Conclusions: Our results show that aerobic exercise did not affect lipid peroxidation of brain, but in diabetic condition improved antioxidant defence.