Screening Myocardial Protective Peptides from Bovine Myocardium Hydrolysates: A Peptidomics-Activity Guided Strategy Integrating Fractionated Extraction, Multivariate Analysis, and Random Forest

This study aimed to investigate the protective effects of bovine myocardium hydrolysates prepared from different protein fractions on H2O2-induced myocardial injury in H9c2 cells and to develop an effective way to explore potential myocardial protective peptides. Results showed that, as compared with bovine heart and its water-soluble protein fraction, myocardium hydrolysate prepared from salt-soluble protein fraction demonstrated better myocardial protective activity, significantly increasing cell viability and activities of antioxidant enzymes (SOD and CAT), while reducing contents of myocardial injury markers (LDH, CK-MB, and cTnT). Ten novel myocardial protective peptides (FR, LK, LPF, RVL, SLL, FDIF, FQPS, GLPPILN, SEAPPHIF, and TEAPLNPK) were identified following a peptidomics-activity guided strategy integrating multivariate analysis and a random forest model. Molecular docking analysis revealed potential molecular mechanisms that might act on myocardial injury-related targets such as AKT1, STAT3, and MMP9. This study may provide insights for the rapid identification of food-derived myocardial protective peptides.