Effect of aqueous extract of Syzygium cumini Pulp on antioxidant defense system in streptozotocin induced diabetic rats

The aqueous extract of Syzygium cumini (Pulp) was investigated for its possible hypoglycemic and antioxidant potentials in streptozotocin (STZ) induced diabetic wistar female rats. A single intraperitoneal injection of STZ at a dose of 55 mg/kg body weight elevated the glucose levels more than 230 mg/dl after 3 days. Treatment with the aqueous extract of Syzygium cumini (Pulp) at 100 mg/kg and 200 mg/kg body weight resulted in significant reduction ( p <0.001) in blood glucose levels. Body weights were significantly reduced ( p <0.001) in STZ Induced diabetic rats when compared to normal rats, while in diabetic rats S.cumini extract ( p <0.001) prevented significantly the decrease in body weight in a dose dependant manner. Total cholesterol, phospholipids, triglycerides, LDL-c, HDL-c levels were altered in STZ induced diabetic rats, which were considerably restored to near normal in animals treated with S.cumini extract .The administration of aqueous extract of Syzygium cumini resulted in significant ( p <0.001) increase in the levels of superoxide dismutase, catalase, glutahione peroxidase, glutathione-S-transferase and reduced glutathione (GSH), thus resulting in reduced free radical formation in liver tissues of the diabetic rats . The increased levels of lipid peroxidation and hydroperoxides in diabetic rats were reverted back to near normal levels after the treatment with aqueous extract of Syzygium cumini . These observations demonstrated that aqueous extract of Syzygium cumini (Pulp) have strong hypoglycemic effect and in vivo antioxidant activity in STZ-Induced diabetic rats and was dose dependent.