Potential cardiac-derived exosomal miRNAs involved in cardiac healing and remodeling after myocardial ischemia-reperfusion injury

Migratory cells exist in the heart, such as immune cells, fibroblasts, endothelial cells, etc. During my-ocardium injury, such as ischemia-reperfusion (MIRI), cells migrate to the site of injury to perform repair functions. However, excessive aggregation of these cells may exacerbate damage to the structure and function of the heart, such as acute myocarditis and myocardial fibrosis. Myocardial injury releases exosomes, which are a type of vesicle with signal transduction function and the miRNA carried by exosomes can control cell migration function. Therefore, regulating this migratory cell population through cardiac-derived exosomal miRNA is crucial for protecting and maintaining cardiac function. Through whole transcriptome RNA sequencing, exosomal miRNA sequencing and single-cell dataset analysis, we (1) determined the potential molecular regulatory role of the lncRNA‒miRNA‒mRNA axis and an important lncRNA (MSTRG.91411.6) in MIRI, (2) screened four important exosomal miRNAs that could be released by cardiac tissue, and (3) screened seven genes related to cell locomo-tion that are regulated by four miRNAs, among which Tradd and Ephb6 may be specific for promoting migration of different cells of myocardial tissue in myocardial infarct. We generated a core miRNA‒mRNA network based on the functions of the target genes, which may be not only a target for cardiac repair but also a potential diagnostic marker for interactions between the heart and other tissues or or-gans. In conclusion, we elucidated the potential mechanism of MIRI in cardiac remodeling from the perspective of cell migration, and inhibition of cellular overmigration based on this network may pro-vide new therapeutic targets for MIRI and to prevent MIRI from developing into other diseases. Rats were treated with left coronary artery ligation for 30 min and then perfused for one week, and heart tissue was taken for transcriptome sequencing