Cardiomyocyte-macrophage cross-talk reduces doxorubicin cardiotoxicity by polarizing macrophages via EV miR-142-3p/135a-5p

Doxorubicin (DOX) cardiotoxicity (DiCM) is mediated by macrophages. c-Kit inhibition drives M2 macrophage polarization, and emerging evidence suggests that cardiomyocyte-derived extracellular vesicles (CM-EVs) participate in immune modulation during cardiac injury. Building on these observations, we hypothesized that cardiomyocyte-specific c-Kit mutation (Tg-Wv) protects against DiCM by altering EV-mediated cardiomyocyte-macrophage crosstalk. In DiCM models, Tg-Wv mice exhibited improved survival, reduced cardiac atrophy, and enhanced function, with a shift toward CD163 + M2 anti-inflammatory macrophages, a higher M2/M1 ratio, and diminished tissue damage, oxidative stress, and apoptosis. CM-EVs reporter mice showed real-time uptake by cardiac macrophages. Micro RNA (miRNA) sequencing identified upregulated miR-142-3p and miR-135a-5p in Tg-Wv cardiomyocytes and EVs. Cardiac macrophages displayed reduced HIF-1α and elevated Arg-1. Transfection of these miRNAs induced CD163 + M2-like polarization in vitro . Our findings demonstrate that cardiomyocyte c-Kit mutation enriches miR-142-3p and miR-135a-5p in EVs, which suppress HIF-1α and promote protective M2-like macrophage polarization, unveiling a novel EV-mediated cardioprotective pathway.