Mcy protein, a potential antidiabetic agent: evaluation of carbohydrate metabolic enzymes and antioxidant status.

The objective of the present study is to elucidate the long-term effects of anti-hyperglycemic active principle, Mcy protein (MCP), isolated from the fruits of Momordica cymbalaria on carbohydrate metabolism and oxidative stress in experimental diabetic rats. We used streptozotocin induced diabetic rats for the current studies. Our studies showed that MCP (2.5mg/kg.b.w) treatment significantly normalized the deranged activities of critical carbohydrate metabolizing enzymes, hexokinase, glucose-6-phosphate dehydrogenase, glucose-6-phosphatase and fructose-1,6-bis phosphatase. In addition MCP showed inhibitory activity on α-glucosidase and aldose reductase enzymes in in vitro assays. Further MCP treatment improved the antioxidant defensive mechanism by preventing deleterious oxidative products of cellular metabolism, which initiates the lipid peroxidation and by normalizing the antioxidant enzyme (catalase, superoxide dismutase, glutathione peroxidase) activities. Additional structural studies using circular dichroism spectroscopy indicate that MCP contains majorly α-helix. Our findings suggest MCP regulates blood glucose and better manage diabetes mellitus associated complications by regulating carbohydrate metabolism and by protecting from the deleterious effects of oxidative stress.

Effect of omega-3 fatty acids on lipid peroxidation and antioxidant enzyme status in type 2 diabetic patients.

BACKGROUND: This study was conducted to investigate the effect of omega-3 fatty acids on lipid peroxidation and antioxidant enzyme activities in non-insulin dependent diabetic patients. METHODS: Thirty-four non-insulin dependent diabetic patients were selected for this study and they were initially treated with antidiabetic drugs alone for one month. This was followed by supplementation with omega-3 fatty acids (1,080 mg of EPA and 720 mg of DHA per day) along with the antidiabetic drugs for a period of two months. RESULTS: No change in glycaemic control was observed in diabetic patients at the end of two months of omega-3 fatty acids therapy along with antidiabetic drugs. The combined treatment significantly reduced serum triglycerides (2.07 +/- 0.94 mmol/l, before combined therapy vs 1.54 +/- 0.49 mmol/l after combined therapy, P<0.05) and increased HDL-cholesterol levels (0.93 +/- 0.099 mmol/l, before combined therapy vs 1.04 +/- 0.098 mmol/l after therapy, P<0.01). The raised lipid peroxide levels (5.14 +/- 0.61 micromol MDA/l in controls vs 6.36 +/- 1.56 micromol MDA/l in diabetic patients, P<0.001) were significantly decreased in these patients after the combined therapy (6.36 +/- 1.56 micromol MDA/l, before combined therapy vs 5.16 +/- 0.7 micromol MDA/l, after combined therapy, P<0.01). Among the erythrocyte antioxidant enzymes, the Glutathione peroxidase activity was increased (32.5 +/- 9.9 U/g Hb/min, before combined therapy vs 42.25 +/- 4.6 U/g Hb/min, after combined therapy, P<0.01) while no change was observed in Catalase (99.7 +/- 30.4 KU/g Hb before combined therapy vs 85.35 +/- 23.41 KU/g Hb, after combined therapy) and Superoxide dismutase activities (2.6 +/- 1.04 U/mg Hb/min, before therapy vs 3.01 +/- 1.08 U/mg Hb/min, after combined therapy) after the 2 months of combined treatment with antidiabetic agents and omega-3 fatty acids. CONCLUSION: Supplementation with omega-3 fatty acids has beneficial effects on serum triglycerides, HDL-cholesterol, lipid peroxidation and antioxidant enzymes, which may lead to decreased rate of occurrence of vascular complications in diabetes.