Trans-anethole, a terpenoid ameliorates hyperglycemia by regulating key enzymes of carbohydrate metabolism in streptozotocin induced diabetic rats

Trans-anethole (TA), a terpenoid and a principle constituent of many essential oils from medicinal plants possess hypoglycemic and antioxidant activities. This study was undertaken to explore beneficial effects of TA on key enzymes of carbohydrate metabolism in streptozotocin (STZ)-induced type 2 diabetic rats. Diabetes was induced in male albino Wistar rats by intraperitoneal administration of STZ (40 mg/kg BW). TA was administered to diabetic rats at a dose of 20, 40 and 80 mg/kg BW for 45 days. However, the dose at 80 mg/kg BW, resulted in a significant reduction in the levels of plasma glucose, glycosylated haemoglobin (HbA1c) and increase in the levels of insulin and haemoglobin (Hb). Upon administration of TA, the altered levels of liver glycolytic enzyme (hexokinase), hepatic shunt enzyme (glucose-6-phosphate dehydrogenase) and gluconeogenic enzymes (glucose-6-phosphatase and fructose-1,6-bisphosphatase) in the liver and kidney of diabetic rats significantly reverted to near normal levels. In addition to this, TA also improved the hepatic and muscle glycogen content in diabetic rats. The histological studies showed the ameliorative effect of TA on the β-cells of pancreas in diabetic rats. The results were compared with glibenclamide, a standard oral hypoglycemic drug. These encouraging findings suggest that TA may be used as a propitious bioactive compound in the development of therapeutic agents against type 2 diabetes mellitus.