Targeting miR-148a-3p to reverse endothelial senescence and improve vascular repair post-MI

Abstract An effective angiogenic response is crucial for tissue repair post-myocardial infarction (MI) but is hindered by senescent endothelial cells (ECs), which reduce regenerative capacity. MicroRNAs (miRs) have been identified as key regulators of angiogenesis and present a promising strategy to improve neovascularization after MI. This study explores miR-148a-3p as a therapeutic target to counteract endothelial senescence, and enhance vascular repair, offering insights into novel CVD management strategies. Expression levels of miR-148a-3p were analysed in Human Coronary Artery Endothelial Cells (HCAECs) and murine tissue via qRT-PCR. Its effects on cellular functions and senescence were assessed post-anti-miR transfection in replicative and non-replicative senescent HCAECs. Target gene and protein expressions were evaluated using qRT-PCR and Western Blot analysis. Analyzing over 1300 patient samples and 1800 miRs from non-tumor control tissues in the Cancer Genome Atlas (TCGA) across ages 20–90, we identified a regulatory network of upregulated miRs with age. MiR-148a-3p played a central role in aging, targeting over 80% of associated mRNAs. In vitro, miR-148a-3p expression was upregulated in replicative senescent ECs (p0.01). In vivo, ECs from old C57BL/6J mice (24-month) exhibited an increase in miR-148a-3p expression compared to young mice (3–6-month; p0.05). Under hypoxia, miR-148a-3p expression decreased in non-senescent ECs (p0.05) but increased in senescent ECs (p0.001). In a mouse model of MI, young C57BL/6J mice showed a miR-148a-3p downregulation in the infarcted heart at 48 hours post-MI (p0.01), whereas old mice exhibited no changes. Anti-miR-148a-3p improved EC functions, including increased proliferation (p0.001), migration (p0.05), sprouting (p0.05), and tube formation (p0.05). Knockdown of miR-148a-3p reduced markers of EC senescence (p0.05) and the senescence-associated secretory phenotype (p0.05), decreased SA-β-gal activity (p0.05), and increased the number of smaller cells and nuclei (p0.05) in both cellular states. Downregulating miR-148a-3p upregulated pro-angiogenic targets NOGO-B (p0.05), AKT1 (p0.001), and HMOX-1 (p0.05) in non-senescent ECs. Inhibiting miR-148a-3p in senescent ECs downregulated pro-senescent targets MAP2K1 and NRAS (p0.05). Protein-level confirmations supported the results (p0.05). In an ultrasound-guided minimal invasive mouse model of MI, systemic antagomiR-148a-3p treatment enhanced cardiac function (fractional shortening, diastolic/systolic left ventricular diameter) and promoted cardiac regeneration (reduced infarct size). The study identifies miR-148a-3p as a key regulator of endothelial senescence and angiogenesis. Anti-miR-148a-3p enhances EC functions and reduces senescence. In a mouse model of MI, antagomiR-148a-3p treatment improves cardiac function and regeneration, suggesting its potential as a therapeutic target for senescence-induced endothelial dysfunction in CVDs.Purpose anti-miR-148a-3p treatment MI