An effective angiogenic response is crucial for tissue repair after myocardial infarction (MI) but is hindered by senescent endothelial cells (ECs), which impair angiogenesis and limit regeneration. MicroRNAs (miRNAs) present a promising strategy to improve neovascularization after MI. Using a publicly available dataset of >1300 patient samples (ages 20–90), we identified a regulatory network of 12 miRNAs systematically upregulated with age, including miR-148a-3p. This study investigates miR-148a-3p as a therapeutic target to counteract endothelial senescence and enhance vascular repair, offering insights into novel CVD management strategies.
Expression of miR-148a-3p was assessed in Human Coronary Artery Endothelial Cells (HCAECs) and murine tissue via qRT-PCR. The effects of its inhibition on endothelial function, senescence, and signaling pathways were investigated in vitro. In vivo, myocardial infarction was induced in young and aged C57BL6/J mice to evaluate therapeutic efficacy.
miR-148a-3p expression was significantly upregulated in replicative senescent HCAEC (p<0.01) and ECs from the aortas of 24-month-old C57BL/6J mice. In non-senescent and senescent HCAEC, the inhibition of miR-148a-3p showed improved cellular functions, including increased proliferation (p<0.01), migration (p<0.05), sprouting (p<0.05), and tube formation (p<0.05). Further, miR-148a-3p knockdown reduced markers of endothelial senescence (p<0.01 to p<0.05) and senescence-associated secretory phenotype (p<0.05), decreased SA-β-gal activity (p<0.05), and increased the number of smaller cell nuclei (p<0.05), in both non-senescent and replicative senescent ECs. To explain our data on the molecular level, we identified targets in silico that are associated with pathomechanisms of MI. Inhibition of miR-148a-3p resulted in upregulation of the pro-angiogenic targets NOGO-B (p<0.05), AKT1 (p<0.001), and HMOX-1 (p<0.05) as well as the anti-inflammatory NFKBIA (p<0.01) in non-senescent ECs. Simultaneously, pro-senescent targets, such as MAP2K1 and NRAS, are downregulated in replicative-senescent ECs upon inhibition of miR-148a-3p (p < 0.05). We next tested the effects of miR-148a-3p inhibition in a mouse model of acute MI in young (3 months) and aged (20-22 months) C57BL/6J mice. Systemic miR-148a-3p inhibition improves clinical recovery markers as body condition score, and improves cardiac function after MI, such as the global longitudinal strain.
In conclusion, miR-148a-3p inhibition enhances endothelial function, reduces senescence, and improves cardiac regeneration in vivo, highlighting its potential as a therapeutic strategy against age-associated vascular dysfunction in CVD.
