Abstract 18810: Mitochondria-Rich Extracellular Vesicles From Stem Cell-Derived Cardiomyocytes Restore Bioenergetic Metabolism of Ischemic Myocardium in a Porcine Chronic Heart Failure Model

Introduction: The disruption of mitochondrial energy metabolism underlies the pathophysiology of ischemic heart failure. We previously demonstrated that intramyocardial injection of mitochondria-rich extracellular vesicles (M-EVs) derived from iPSC-derived cardiomyocytes (iCMs) transfers mitochondria and non-mitochondrial biologics into recipient cardiomyocytes. This process stimulates mitochondrial biogenesis and enhances functional capacities in murine and porcine acute myocardial infarction (MI) models. However, the therapeutic potential and underlying mechanism in chronic heart failure models remain to be assessed. Method: M-EVs were isolated from the conditioned medium of human iCMs using differential centrifugation. A total of 11 Yorkshire pigs underwent myocardial ischemia for one hour via balloon occlusion of the left anterior descending artery (Week-0). At week-4, 1.0 x 10 11 M-EVs or PBS control were administered transendocardially to the peri-infarct region (PIR) using a percutaneous catheter delivery system (Biocardia, Inc, CA). Cardiac functions and scar size were analyzed by cardiac MRI with gadolinium contrast at week-4 (pre-injection) and -8 (post-injection). Myocardial tissue samples were collected from the PIR and remote non-ischemic areas at week-8. Proteomic analysis and single-nucleus RNA sequencing were performed to investigate comprehensive protein and gene expression profiles of the myocardium. Results: Left ventricular (LV) ejection fractions were significantly decreased at Week-4 (32.7±5.4%). M-EV treatment significantly improved absolute LVEF from week-4 to -8 in the treatment vs. non-treatment groups, +3.15% vs. -4.99%, respectively, (p<0.0001). No significant difference was observed in the scar size. Multiomic analysis of proteomes and single-nucleus transcriptomes suggested restoration of dysregulated cardiometabolic protein profile and mitochondrial energy metabolism in the myocardium. Conclusion: M-EV-mediated transfer of mitochondria and enriched proteins augmented LV dysfunction in the pig chronic MI model. M-EV therapy may represent a novel biologic approach that directly targets cardiac metabolism by restoring mitochondrial function and cellular bioenergetics.