inhibitory effects in vitro

Objective: Dipeptidyl peptidase IV (DPP IV) is a serine amino (exo) peptidase which regulates various processes most notably plasma glucose homeostasis by cleaving incretin peptide hormones as glucagon-like peptide-1 (GLP-1) and glucose-dependent insulin releasing polypeptide (GIP). Realization of the inhibition of this enzyme in controlling diabetes is one of the strategies adopted in recent years. The present study was designed to investigate the DPP IV inhibitory effects of sixteen plant having antidiabetic property in aqueous extracts in correlation with their protein content.Methods: In vitro DPP IV inhibition was evaluated by the specific inhibitory activity of plant aqueous extracts prepared without and with heat (60 degrees C) treatment.Results: Among the tested plants Vitis vinifera L., Artemisia dracunculus L., Prunus laurocerasus L., Rubus caesius L. and Olea europaea L. extracts showed DPP IV inhibitory activity with respect to IC50 values of 0.04-0.09 mg protein/ml. Kinetic analysis indicated that the inhibitor potency of A. dracunculus extract was stronger than the other extracts.Conclusion: The present study is the first report on screening and preliminary characterization of DPP IV inhibitory activity in aqueous extracts of selected antidiabetic medicinal food. This study could provide a new insight into DPP IV inhibitors from plants that could be useful for treatment of Type 2 diabetes