Targeting ferroptosis with chenodeoxycholic acid improves residual cardiac dysfunction after surgical ventricular...

Surgical ventricular reconstruction (SVR) partially reverses left ventricular remodelling in postinfarction heart failure, yet residual cardiac dysfunction persists through unknown mechanisms. We investigated ferroptosis involvement in post-SVR pathology and explored pharmacological interventions.

Myocardial infarction (MI) was induced in C57BL/6 mice followed by SVR at 4 weeks. Cardiac function was assessed by echocardiography and pressure-volume catheterization. Ferroptosis biomarkers were quantified. Connectivity Map analysis identified candidate compounds validated in Erastin-challenged AC16 cardiomyocytes and SVR mouse models.

Compared with MI group, SVR improved the left ventricular end-diastolic volume index by 36.8% but showed persistent iron overload, glutathione depletion and elevated malondialdehyde. Transcriptomic analysis identified 90 ferroptosis-related differentially expressed genes following SVR. Connectivity Map prioritized three ferroptosis inhibitors, and chenodeoxycholic acid (CDCA) exhibited superior efficacy. Farnesoid X receptor (FXR) knockdown in AC16 cardiomyocytes exacerbated erastin-induced ferroptosis, while CDCA co-treatment significantly reduced erastin-induced ROS production, upregulated glutathione peroxidase 4 (GPX4) expression, and restored superoxide dismutase activity, rescued the ferroptotic phenotype and reversed associated molecular changes in FXR-knockdown cells. In SVR-treated mice, 3-week CDCA administration (50 mg·kg^-1·day^-1) reduced myocardial iron deposition by 14.8%, improved left ventricular ejection fraction from 23.73% to 31.61% and restored GSH/GSSG ratio from 1.645 to 1.988. CDCA up-regulated GPX4 expression by 1.573-fold compared with the vehicle group.

SVR paradoxically exacerbates ferroptosis in residual myocardium through iron dysregulation and antioxidant depletion. CDCA, a primary bile acid activating FXR signalling, is a novel pharmacological strategy to mitigate post-SVR ferroptosis and improve cardiac outcomes.