부산대학교 도서관

Abstract Introduction Wound healing after myocardial infarction (MI) is mediated by different cell types, secreted proteins, components of the extracellular matrix (ECM) and, as increasing evidences suggest, extracellular vesicles (EVs). We aim to determine the dynamics of release and origin of EVs after MI, as well as their biological activity on endothelial cells (ECs). Methods MI was induced in WT mice and blood and tissues collected at baseline, 3, 15 and 30 days post-ligation for cardiac function (echocardiography) and histological evaluation. Circulating EVs subpopulations were measured by flow cytometry in mouse, and in a small cohort of patients with ST-segment elevation MI (STEMI, n = 6). In vitro, EVs were isolated from a cardiomyocyte cell line (HL1) and their function assayed on ECs. Results Leukocyte and endothelial EVs increased concomitant to inflammatory and angiogenic processes triggered by ischemia. More strikingly, cardiomyocyte EVs (connexin43+) were detected in STEMI patients and in murine MI, where a significant increase in their levels was reported at day 15 post-ischemia (p < 0.05 vs baseline). In vitro, HL1EVs induced ECs migration (p = 0.05) and proliferation (p < 0.05), but impaired tube formation. These apparent contradictory results could be partially explained by the upregulation of MMP3, and the apoptosis and senescence genes, p53 and p16 , induced by HL1EVs on ECs (p < 0.05). Conclusions MI induces the release of different EVs subpopulations, including those of cardiac origin, in a preclinical model of MI and STEMI patients. In vitro, cardiomyocyte derived EVs are able to modulate endothelial function, suggesting their active role in heart repair after ischemia. Highlights • Dynamics of extracellular vesicle release after myocardial infarction are studied. • Leukocyte EVs are associated with early inflammation post-MI. • Endothelial EVs fluctuation mimics angiogenic processes in the ischemic heart. • Cardiomyocyte EVs increase after injury in human and mouse plasma post-MI. • Cardiomyocyte derived EVs modulate endothelial function in vitro. [ABSTRACT FROM AUTHOR]