Effect of methanolic extract of Dennettia tripetala (pepper fruit) on biomarkers of oxidative stress and lipid peroxidation in type 2 diabetic male wistar rats

Oxidative stress resulting from chronic hyperglycemia in diabetes is due to high production of reactive oxygen species and/or a decrease in the antioxidant defense system activity. The study was designed to investigate the ameliorative effect of methanolic extract of Dennettia tripetala (DT) on oxidative stress and blood glucose level in type II diabetic male Wistar rats. Type II diabetes was induced by a single intraperitoneal injection of streptozotocin (40 mg/kg) after 2 weeks of 10% fructose diet. Twenty-five (25) rats were randomly divided into five groups, namely: 1 (normal control), 2 (negative control), 3 (10 mg/kg of glibenclamide), 4 (100 mg/kg of DT extract) and 5 (200 mg/kg of DT extract). The administration of the extract caused a significant decrease in blood glucose levels in all treatment groups. A significant (Pu003c0.01) decrease in malonaldehyde (MDA) activity was observed in the group treated with 100 and 200 mg/kg of DT extract compared to diabetic control. Catalase (CAT) activity showed a significant (Pu003c0.05) increase in the group treated with 200 mg/kg of DT extract compared to the normal control. However, the extract did not affect GSH-Px, SOD and CAT activities. The findings suggest ameliorative effect of DT extract in diabetic Wistar rats. Key words: Dennettia tripetala, diabetes mellitus, oxidative stress, lipid peroxidation, Wistar rats.