Antidiabetic activity of benzopyrone analogues in nicotinamide-streptozotocin induced type 2 diabetes in rats.

Benzopyrones are proven antidiabetic drug candidate in diabetic drug discovery. In this view novel synthetic benzopyrone analogues were selected for testing in experimental diabetes. Type 2 diabetes (T2D) was induced in Wistar rats by streptozotocin (60 mg/kg, i.p.) followed by nicotinamide (120 mg/kg i.p.). Rats having fasting blood glucose (FBG)>200 mg/dL, 7 days after T2D-induction, are selected for the study. Test compounds and standard treatment were continued for 15 days. FBG, oral glucose tolerance test (OGTT), and insulin tolerance test (ITT) were determined on 21st day after induction of T2D. Plasma lipids and serum insulin were estimated. Homeostatic model assessment (HOMA-IR) was then calculated from serum insulin. Rats were sacrificed and pancreas was isolated for histopathological observations. Oxidative stress markers were estimated in liver homogenate. Quercetin, a natural product with benzopyrone ring, showed significant hypoglycemic activity comparable to glibenclamide. Treatment with test compounds lowered the FBG and insulin resistance was significant alleviated as determined by OGTT, HOMA-IR, and ITT. There was significant normalisation of liver antioxidant enzymes compared to diabetic rats indicating that all the synthesised benzopyrone analogues are beneficial in reducing oxidative stress and are on par with the standard quercetin and glibenclamide in experimental T2D.