A study in mice identified 174 differentially expressed mature miRNAs in heart tissue exosomes following acute myocardial infarction, with in vitro validation showing that mimics of 19 selected miRNAs, including mmu-miR-30c-1-3p and mmu-miR-149-3p, significantly reduced hypoxic stress-induced cell death in primary cardiomyocytes [Jung et al. DOI:10.3390/biomedicines12020430].