Sex-specific cardioprotective role of miR-30a-5p through estrogen-dependent mechanisms in a mouse model of heart failure.

BACKGROUND: In recent years, except for the well-known heart failure with reduced ejection fraction (HFrEF), the incidence of heart failure with preserved ejection fraction (HFpEF) and heart failure with mildly reduced ejection fraction (HFmrEF) among the classification of heart failure (HF) has been increasing. However, due to their complex mechanisms, current research remains insufficient to address clinical needs. METHODS AND RESULTS: Utilizing wild-type (WT), miR-30a-5p knockout (KO), and overexpression (OE) murine models combined with estrogen modulation and ovariectomy (OVX), this study delineates sex-specific regulatory networks in HF pathogenesis. Female KO mice lost the inherent resistance of WT females to HFpEF induction via 24-week HFD/L-NAME, whereas males exhibited comparable HFpEF susceptibility regardless of genotype, developing hallmark phenotypes including diastolic dysfunction (E/E'), myocardial hypertrophy (heart weight/tibia length), cardiac fibrosis, and hepatic steatosis. Particularly, due to the reduced ejection fraction in KO mice, combined with HFD/L-NAME, the HF phenotype was ultimately manifested as impaired diastolic function and slightly reduced ejection fraction (with the characteristics of HFpEF and HFmrEF). Mechanistically, KO-HF females displayed significant estrogen axis disruption (plasma estradiol and the expression of ERα, ERβ, ESRRA, and PELP1 expression). OVX in WT females validated the importance of estrogen for HFpEF resistance. Transcriptomic profiling identified convergent targets across cardiac (ITGAD, ITGAM, FGA, and FGB) and hepatic tissues (APOA1 and APOB), revealing miR-30a-5p's orchestration of extracellular matrix remodeling (via ITGAD/ITGAM mechanotransduction),fibrinogen-mediated microvascular homeostasis, and APOB-driven metabolic dysregulation. Notably, OE intervention failed to mitigate OVX-induced cardiac/hepatic pathology, implicating estrogen-dependent miR-30a-5p functionality. CONCLUSIONS: These findings establish miR-30a-5p as a crucial sex-specific regulator of HF (mainly HFpEF), operating through estrogen signaling to balance cardiac compliance and metabolic adaptation.