The denitrosylase SCoR2 controls cardioprotective metabolic reprogramming.

Abstract

Acute myocardial infarction (MI) is a leading cause of morbidity and mortality, and therapeutic options remain limited. Endogenously generated nitric oxide (NO) is highly cardioprotective, but protection is not replicated by nitroso-vasodilators (e.g., nitrates, nitroprusside) used in clinical practice, highlighting specificity in NO-based signaling and untapped therapeutic potential. Signaling by NO is mediated largely by <i>S</i>-nitrosylation, entailing specific enzymes that form and degrade <i>S</i>-nitrosothiols in proteins (SNO-proteins), termed nitrosylases and denitrosylases, respectively. SNO-CoA Reductase 2 (SCoR2; product of the <i>Akr1a1</i> gene) is a recently discovered protein denitrosylase. Genetic variants in SCoR2 have been associated with cardiovascular disease, but its function is unknown. Here, we show that mice lacking SCoR2/AKR1A1 exhibit robust protection in an animal model of MI. SCoR2 regulates ketolytic energy availability, antioxidant levels, and polyol homeostasis via <i>S</i>-nitrosylation of key metabolic effectors. Human cardiomyopathy shows reduced SCoR2 expression and an <i>S</i>-nitrosylation signature of metabolic reprogramming, mirroring SCoR2^-/- mice. Deletion of SCoR2 thus coordinately reprograms multiple metabolic pathways-ketone body utilization, glycolysis, pentose phosphate shunt, and polyol metabolism-to limit infarct size, establishing SCoR2 as a novel regulator in the injured myocardium and a potential drug target.