Beneficial effect of carvone, a dietary monoterpene ameliorates hyperglycemia by regulating the key enzymes activities of carbohydrate metabolism in streptozotocin-induced diabetic rats

Diabetes mellitus is a common metabolic/endocrine disorder characterized by inadequate control of carbohydrate metabolism and causes serious health issues. This study evaluates the effect of carvone, a novel monoterpene ketone, on carbohydrate metabolic enzymes in the liver of normal and streptozotocin (STZ)-induced diabetic rats. Diabetes was induced by a single intraperitoneal injection of STZ (40 mg/kg b.w). STZ intoxication led to a significant increase in the levels of plasma glucose, glycosylated hemoglobin (HbA(1c)) and decrease in the levels of insulin and hemoglobin (Hb). The activities of carbohydrate metabolic enzymes, glycogen, enzymatic antioxidants in pancreas and hepatic markers content were also altered. The daily oral administration of carvone (50 mg/kg b.w) to diabetic rats for 30 days resulted a significant decline in the levels of plasma glucose, HbA(1c) and significant improve in the levels of Hb and insulin. The reversed activities of carbohydrate metabolic enzymes, enzymic antioxidants and hepatic marker enzymes in diabetic rats were renovated to near normal level by the administration of carvone. The obtained results were compared with glyclazide, a standard oral hypoglycemia drug. Histopathological analysis of liver and pancreas and immunohistochemistry of pancreas revealed that treatment with carvone reduced the STZ-induced damage to hepatic and beta-cells of the pancreas. From our results, carvone regulates carbohydrate metabolism by ameliorating the key enzymes in the hepatic tissues of STZ-induced diabetic rats however further studies and safety studies are needed to validate the effects of carvone. (C) 2016 Elsevier Masson SAS. All rights reserved.