The role of selenium on vessel function in diabetic rats induced by high fat diet and streptozotocin

The Role of Selenium on Vessel Function in Diabetic Rats Induced by High Fat Diet and StreptozotocinEndothelial dysfunction is responsible for diabetic vascular complications, develops as a result of oxidative stres and its pathological process. Selenium is a antioxidant essential element. Inthis study we investigate the effects of selenium on endothelial disfunction and oxidative stress in type 2 diabetic rats. The rats were divided 5 groups as control, diabetic group without treatment and diabetic group with treatment in 3 different selenium doses (180- 300- 500 mcg/kg/day). To develop of the type 2 diabetic rat model, the diabetic rats were fed the high fat diet (HFD) until the end of study and the control rats were fed regular chow. The diabetic groups were injected intraperitoneally (i.p) twice, with low doses streptozotocin (30 mg/kg). To invstigate th effects of diabetes and selenium in diabetic rats induced by high fat diet and multipl low doses intraperitoneal streptozotocin, acetylcholine and sodium nitroprusside induced relaxation, also eNOS and NADPH oxidase (NOX4) mRNA expressions, were measured in rat thoracic aortas. The expressions of NOX4 were significantly decreased with selenium treatmnent, while its expressions were increased in aortas from diabetic rats without treatment. . The expressions of eNOS were significantly increased with selenium treatmnent, while its expressions were decreased in aortas from diabetic rats without treatment. Moreover, in blood samples of rats fasting blood glucose, lipid profile, lipid peroxidation (MDA), insulin and NO, also in rat liver samples MDA, SOD, CAT and GPx levels were measured. Selenium treatment significantly increased fasting blood glucose, total colesterol, trigliserid levels, also catalase and MDA levels in liver in diabetic rats. GPx levels, increased in diabetes, were decreased with selenium. The results showed that selenium restores the vascular responses and endothelial dysfunction in diabetes through increased NO levels and eNOS expressions.Key words: type 2 diabetes, selenium, nitric oxide, endothelial dysfunction, oxidative stress, high fat diet