Antidiabetogenic efficiency of menthol, improves glucose homeostasis and attenuates pancreatic ß-cell apoptosis in streptozotocin-nicotinamide induced experimental rats through ameliorating glucose metabolic enzymes.

The phytochemical, menthol, has been reported to play many beneficial roles. However, under diabetic conditions, there is no detail mechanism of its beneficial action in the glucose homeostasis. The present study, we investigated to explore the role of menthol, on the glucose metabolic enzymes and pancreatic islet cell apoptosis of streptozotocin-nicotinamide (STZ-NA) induced diabetes in rats. Diabetes was induced by single intraperitoneal (i.p.) injection of STZ (50mg/kg/b.w.) and NA (110mg/kg/b.w.). Diabetic rats were treated with different dose of menthol (25, 50, and 100mg/kg/b.w.) and glibenclamide (600µg/kg/b.w.) daily for 45 days. The result of our study shows that menthol significantly reduced the blood glucose and glycosylated hemoglobin levels and significantly increased the total hemoglobin, plasma insulin and liver glycogen levels in diabetic rats. The altered activities of hepatic glucose metabolic enzymes, serum biomarkers of liver damage were restored to near normal. The pathological abnormalities in hepatic and pancreatic islets of diabetic rats were significantly ameliorated by menthol intervention. These effects were mediated by suppressing pancreatic ß-cells apoptosis and were associated with increased anti-apoptotic Bcl-2 expression and reduced pro-apoptotic Bax expression. Findings from the current study consent us to conclude that menthol alleviates STZ-NA-induced hyperglycemia via modulating glucose metabolizing enzymes, suppression of pancreatic ß-cells apoptosis and altered hepatic, pancreatic morphology. This exclusivity and dearth of any noticeable adverse efficacy proposes the opportunity of using this monoterpene as an efficient adjuvant in the management diabetes mellitus.

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 (40mg/kg b.w). STZ intoxication led to a significant increase in the levels of plasma glucose, glycosylated hemoglobin (HbA1c) 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 (50mg/kg b.w) to diabetic rats for 30days resulted a significant decline in the levels of plasma glucose, HbA1c 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 ß-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.

Antidiabetic efficacy of citronellol, a citrus monoterpene by ameliorating the hepatic key enzymes of carbohydrate metabolism in streptozotocin-induced diabetic rats.

Diabetes mellitus is a clinically complex disease characterized by chronic hyperglycemia with metabolic disturbances. During diabetes, endogenous hepatic glucose production is increased as a result of impaired activities of the key enzymes of carbohydrate metabolism. The purpose of the present study was to evaluate the antidiabetic efficacy of citronellol, a citrus monoterpene in streptozotocin (STZ)-induced diabetic rats. Diabetes mellitus was induced by a single intraperitoneal injection of STZ (40 mg/kg b.w). STZ induced diabetic rats received citronellol orally at the doses of 25, 50, and 100 mg/kg b.w for 30 days. In this study the levels of plasma glucose, insulin, hemoglobin (Hb), glycated hemoglobin (HbA1C), glycogen, and the activities of carbohydrate metabolic enzymes, liver and kidney markers were evaluated. Oral administration of citronellol (50 mg/kg) for 30 days dose dependently improved the levels of insulin, Hb and hepatic glycogen with significant decrease in glucose and HbA1C levels. The altered activities of carbohydrate metabolic enzymes, hepatic and kidney markers were restored to near normal. Citronellol supplement was found to be effective in preserving the normal histological appearance of hepatic cells and insulin-positive ß-cells in STZ-rats. Our results suggest that administration of citronellol attenuates the hyperglycemia in the STZ-induced diabetic rats by ameliorating the key carbohydrate metabolic enzymes and could be developed as a functional and nutraceutical ingredient in combating diabetes mellitus.

Ameliorating effect of eugenol on hyperglycemia by attenuating the key enzymes of glucose metabolism in streptozotocin-induced diabetic rats.

Epidemiological studies have demonstrated that diabetes mellitus is a serious health burden for both governments and healthcare providers. This study was hypothesized to evaluate the antihyperglycemic potential of eugenol by determine the activities of key enzymes of glucose metabolism in streptozotocin (STZ)-induced diabetic rats. Diabetes was induced into male albino Wistar rats by intraperitoneal administration of STZ (40 mg/kg body weight (b.w.)). Eugenol was administered to diabetic rats intragastrically at 2.5, 5, and 10 mg/kg b.w. for 30 days. The dose 10 mg/kg b.w. significantly reduced the levels of blood glucose and glycosylated hemoglobin (HbA1c) and increased plasma insulin level. The altered activities of the key enzymes of carbohydrate metabolism such as hexokinase, pyruvate kinase, glucose-6-phosphate dehydrogenase, glucose-6-phosphatase, fructose-1,6-bisphosphatase, and liver marker enzymes (AST, ALT, and ALP), creatine kinase and blood urea nitrogen in serum and blood of diabetic rats were significantly reverted to near normal levels by the administration of eugenol. Further, eugenol administration to diabetic rats improved body weight and hepatic glycogen content demonstrated the antihyperglycemic potential of eugenol in diabetic rats. The present findings suggest that eugenol can potentially ameliorate key enzymes of glucose metabolism in experimental diabetes, and it is sensible to broaden the scale of use of eugenol in a trial to alleviate the adverse effects of diabetes.