Allosteric activation of pyruvate carboxylase by Dracoflavan Benhances endothelial energy metabolism to attenuate myocardial infarction.

Abstract

BACKGROUND: Myocardial infarction (MI) is a life-threatening cardiovascular event characterized by ischemic necrosis and endothelial cell (EC) dysfunction, which exacerbates tissue injury and impairs repair. Mitochondrial dysfunction, a central contributor to MI pathogenesis, disrupts energy metabolism and promotes oxidative stress. Pyruvate carboxylase (PC), a key mitochondrial anaplerotic enzyme, replenishes TCA cycle intermediates and sustains cellular bioenergetics, yet its role in endothelial protection during MI remains unclear. PURPOSE: This study aims to investigate the cardioprotective effects and underlying mechanisms of Dracoflavan B(DB), a natural compound derived from Daemonorops draco Bl., with a focus on its mitochondrial-targeted action in endothelial cells under ischemic injury. METHODS: The protective effect of DBwas evaluated both in vitro using oxygen-glucose deprivation (OGD)-induced EC injury models and in vivo in a murine MI model. A photoaffinity probe incorporating a diazirine crosslinker and clickable handle was developed to identify direct cellular targets of DB. Chemogenetic profiling, enzymatic assays, and metabolic flux analysis were employed to elucidate the molecular interactions and functional consequences of DBon PC activity and mitochondrial metabolism. RESULTS: DBsignificantly ameliorated OGD-induced EC injury and improved cardiac function in MI mice. Target identification revealed PC as a direct binding protein of DB. Mechanistically, DBacted as an allosteric agonist of PC, promoting a conformational shift that enhanced oxaloacetate production, replenished TCA cycle intermediates, and restored mitochondrial oxidative phosphorylation and ATP synthesis. DBtreatment counteracted OGD-induced metabolic disruption and sustained endothelial bioenergetic homeostasis. CONCLUSION: Our findings demonstrate that DBprotects against myocardial ischemic injury by targeting PC and enhancing mitochondrial anaplerotic flux, thereby preserving endothelial function and myocardial energetics. This study identifies DBas a novel allosteric PC agonist with translational potential for the treatment of MI and highlights mitochondrial metabolic reprogramming as a promising therapeutic strategy in cardiovascular diseases.