Antidiabetic and antihyperlipidemic activity of ethyl acetate:Isopropanol (1:1) fraction of Vernonia anthelmintica seeds in Streptozotocin induced diabetic rats

Ethanolic extract prepared from the seeds of Vernonia anthelmintica was evaluated for its antihyperglycemic activity in STZ (Streptozotocin) induced diabetic rats. Administration of ethanolic extract at a dosage of 0.50 g/kg bw produced the maximum fall (82%) in the blood glucose levels in diabetic rats after 6 h of treatment. Bioassay-directed fractionation using silica gel column chromatography was performed. Among the five fractions (A1, B1, C1, A2 and B2) obtained, of an initial chromatographic separation of the ethanolic extract, fraction A2 (100 mg/kg bw) showed the maximum antihyperglycemic activity which is significantly higher than that of the reference drug glibenclamide (20 mg/kg bw). Administration of the active fraction (100 mg/kg bw) for 45 days resulted in significant reduction in plasma glucose, HbA1(C), cholesterol, triglycerides, LDL, VLDL, free fatty acids, phospholipids and HMG-CoA reductase in STZ diabetic rats. In addition to that, significant decrease in plasma insulin, protein, HDL and hepatic glycogen observed in STZ diabetic rats, was normalized after 45 days of treatment with the active fraction of V. anthelmintica seeds. From the present study, it is evident that, the seeds of V. anthelmintica possess significant antidiabetic and antihyperlipidemic property without evident toxic effects.