Antidiabetic and antioxidative effects of hydro-methanolic extract of sepals of Salmalia malabarica in streptozotocin induced diabetic rats

Natural products with antidiabetic activities provide important sources for the development of new drugs in the treatment of diabetes mellitus. This present work focuses on the antidiabetic activity of a hydro-methanolic (2:3) extract of the sepals of Salmalia malabarica on the blood glucose, the carbohydrade metabolic enzyme, oxidative stress, glycated haemoglobin and transaminase activity in streptozotocin (STZ) induced diabetic rats. Diabetic rats show a significant diminution in the activities of hexokinase, glucose-6-phosphate dehydrogenase and an elevation in the activity of glucose-6-phosphatase in the liver and skeletal muscle. Administration of hydro-methanolic extract of the sepals of Salmalia malabarica to diabetic rats resulted in a significant recovery in the parameters concerned. In the liver and kidney, the activities of catalase (CAT) and peroxidase (Px) were decreased significantly and levels of conjugated diene (CD) and thio-barbituric acid reactive substance (TBARS) were increased significantly in diabetic rats which recovered significantly after administration of hydro-methanolic extract of S. malabarica. Serum glutamate oxaloacetate transaminase (SGOT) and serum glutamate pyruvate transaminase (SGPT) activities which are increased in diabetes were restored by the extract. Glycated haemoglobin (HbA(1C)) levels were resettled significantly in the extract treated group compared to the diabetic group. The antidiabetic activity of the extract was supported after a comparison with glibenclamide, a standard antidiabetic drug.