Genetic deletion or pharmacological inhibition of acetyl-CoA carboxylase 2 enhances fatty acid oxidation and improves cardiac function and survival in the murine ATGL knockout model of severe heart failure

Abstract

Impaired myocardial energetics, including fatty acid oxidation (FAO), is a hallmark feature in the pathophysiology of various disorders. Deficiency of adipose triglyceride lipase (ATGL) results in impaired FAO which leads to severe heart failure due to massive triglyceride accumulation in cardiac muscle and coronary vasculature. Acetyl-CoA carboxylase 2 (ACC2) is a mitochondrial enzyme that regulates FAO; ACC2 inhibition increases transport of fatty acids into mitochondria for oxidation. In this study, the murine ATGL knockout (KO) model of severe heart failure was used to evaluate the effects ACC2 inhibition induced by whole body genetic KO (Atgl/Acc2 double KO mice) and pharmacological inhibition with TLC-3595, an oral, selective small molecule inhibitor of ACC2. Both genetic deletion of Acc2 and treatment with TLC-3595 in Atgl KO mice promoted mitochondrial FAO, reduced cardiac lipid accumulation and remodeling, and led to significant improvements in cardiac function, locomotor activity, and survival. Metabolite profiling of cardiac tissue of Atgl/Acc2 double KO mice and Atgl KO mice treated with TLC-3595 revealed ACC2-specific changes, including reduced malonyl-CoA and increased short-, medium-, and long-chain acylcarnitines, consistent with improved FAO. These findings support the therapeutic targeting of ACC2 for the treatment of heart failure associated with impaired FAO.