earticle

영어

Cyclo (His-Pro) (CHP) is a naturally occurring cyclic dipeptide structurally related to thyrotropin-releasing hormone (TRH). The major goal of the current study was to determine whether the CHP plays important role in Type I diabetes. The experiment was designed to investigate the effect of CHP on glucose metabolism in vivo (Type I diabetes model). CHP (approx. 11 mg/g of dry weight) was efficiently obtained from soybean meal by proteolytic hydrolysis using the mixture of Flavourzyme and Alcalase. When Type I rats (Sprague-Dawley) induced with streptozotocin (50 mg/kg BW) were administrated by CHP (4 mg/kg BW), blood glucose level in the CHP-fed rats was remarkably decreased by approximately 56% as compared to the diabetes group. In the oral glucose tolerance test, blood glucose levels were restored to its baseline after 120 min by CHP treatment, although blood glucose levels increased significantly after 30 min. Insulin level in plasma was also restored by 29%, compared to the STZ-treated rat and triglyceride levels were normalized in CHP-treated rats, whereas no effects of CHP treatment on cholesterol level were observed. Moreover, a histopathological examination showed that CHP administration could restore the impaired β-cells of pancreas to the normal level. Accordingly, the CHP exhibited an excellent hypoglycemic effect by lowering average plasma glucose levels, increasing insulin secretion, and restoring viability of pancreatic β-cells in diabetic rats. Considering these results, we suggest that the CHP might be a candidate material to control Type I diabetes mellitus.