Identification of dipeptidyl peptidase-IV inhibitory peptides from yak bone collagen by in silico and in vitro analysis

The fast development of bioinformatics and various established databases of bioactive peptides provide time-saving and efficient method for identifying bioactive peptides from various proteins. The yak bone collagen is rich in nutrition and have various potential bioactivities, but the study on yak bone collagen as a precursor of antidiabetic peptide has not been reported. In this study, yak bone collagen was first evaluated as a precursor to generate dipeptidyl peptidase-IV (DPP-IV) inhibitory peptides by in silico analysis. After multi-cycles of screening, three peptides (GHR, GIR and MGPR) were screened out and synthesized to evaluate their inhibitory activities in vitro. Among the three peptides, MGPR had the best inhibitory effect on DPP-IV with IC50 of 0.490 ± 0.012 mM. Further cell test verified that MGPR could ameliorate glucosamine-induced glucose uptake reduction in HepG2 cells. These results suggested that yak bone collagen could be applied as a good precursor for antidiabetic peptides. This study would further broaden the application of yak bone collagen in the fields of the food and pharmaceuticals industry.Graphical abstract