Dipeptidyl Peptidase- IV Inhibitory Activity of Berberis aristata

Glucagon-like peptide-1 (GLP-1) is an insulinotropic gut hormone. It enhances meal-induced, glucose-dependent insulin secretion (incretin effect) and restores glucose competency to the beta-cells of pancreas. GLP-1 also inhibits meal-induced gastric acid secretion and gastric emptying, thereby reducing postprandial glucose excursions which is an advantage in Type 2 diabetes. However, the major limiting factor of GLP-1 is its susceptibility to degradation by dipeptidyl peptidase IV (DPP-IV) enzyme. Also GLP-1 has a short plasma half life of only 1-2 minutes. Therefore, it becomes a requisite to identify DPP-IV inhibitors that act as potential antidiabetic agents. Though there are few commercial DPP-IV inhibitors (Vildagliptin, Sitagliptin and Saxagliptin) are available in the market, they have some undesirable side effects. In this context, our study had focused to screen few medicinal plants for DPP-IV inhibiting activity. Among the eight plants screened, we have identified the methanolic extract of the bark of tree turmeric (Berberis aristata) has the ability to inhibit dipeptidyl peptidase IV activity (in vitro). The crude bark extract had shown IC50 value of 14.4µg/ml and the standard diprotin-A displayed 1.5µg/ml