International Journal of Molecular Sciences Review Discovery of Food-Derived Dipeptidyl Peptidase IV Inhibitory Peptides: A Review Rui Liu 1,2,3,4 , Jianming Cheng 1,2,3,* and Hao Wu 1,2,3,* 1 Jiangsu Key Laboratory of Research and Development in Marine Bio-resource Pharmaceutics, Nanjing University of Chinese Medicine, Nanjing 210023, China;
[email protected] 2 Jiangsu Collaborative Innovation Center of Chinese Medicinal Resources Industrialization, National and Local Collaborative Engineering Center of Chinese Medicinal Resources Industrialization and Formulae Innovative Medicine, Nanjing 210023, China 3 School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing 210023, China 4 School of Pharmacy, University of Wisconsin-Madison, Madison, WI 53705, USA * Correspondence:
[email protected] (J.C.);
[email protected] (H.W.); Tel.: +86-25-85811524 (J.C.); +86-25-85811206 (H.W.) Received: 21 December 2018; Accepted: 19 January 2019; Published: 22 January 2019 Abstract: Diabetes is a chronic metabolic disorder which leads to high blood sugar levels over a prolonged period. Type 2 diabetes mellitus (T2DM) is the most common form of diabetes and results from the body’s ineffective use of insulin. Over ten dipeptidyl peptidase IV (DPP-IV) inhibitory drugs have been developed and marketed around the world in the past decade. However, owing to the reported adverse effects of the synthetic DPP-IV inhibitors, attempts have been made to find DPP-IV inhibitors from natural sources. Food-derived components, such as protein hydrolysates (peptides), have been suggested as potential DPP-IV inhibitors which can help manage blood glucose levels. This review focuses on the methods of discovery of food-derived DPP-IV inhibitory peptides, including fractionation and purification approaches, in silico analysis methods, in vivo studies, and the bioavailability of these food-derived peptides.