MEDICINAL CHEMISTRY RESEARCH, cilt.19, ss.364-374, 2010 (SCI-Expanded)
Increased oxidant stress plays an important role in the etiopathogenesis of chronic complications of diabetes. This study aimed to examine the effects of ascorbic acid (vitamin C, AA) supplementation on the oxidant and antioxidant processes in the brain of diabetic rats. Wistar albino rats were divided into four groups: group 1 (control), group 2 (ascorbic acid, AA, vitamin C), group 3 (diabetes), and group 4 (diabetes + AA). The rats were treated with a single dose of streptozotocin (45 mg/kg, intraperitoneal) to induce diabetes. After 48 h, the rats whose fasting blood glucose levels exceeded 200 mg/100 mL were included in the diabetes groups. The rats in the AA and diabetes + AA groups were treated with AA (20 mg/kg/day), administered intragastrically for 21 days. At the end of the experiment, malondialdehyde (MDA), glutathione (GSH), AA, and total nitric oxide (NOx) levels in the liver tissues were determined. Analysis of variance (ANOVA) and Mann-Whitney U tests were used for statistical analyses. Whereas the MDA levels increased in the diabetes group, the NOx levels decreased. The NOx levels increased in the diabetes + AA group compared with the control subjects. There were no significant differences in the diabetes + AA group in terms of GSH levels. In conclusion, vitamin C or vitamin C preparations may be beneficial in the treatment of diabetic patients for maintenance of the brain cells against oxidative damage.