Liraglutide modulates ALCAT1-Mediated cardiolipin remodeling to improve cardiac function in obese mice

Obesity, a significant risk factor for cardiovascular diseases, induces cardiolipin (CL) remodeling. Acyl-CoA:lysocardiolipin acyltransferase-1 (ALCAT1), a key enzyme in CL metabolism, drives mitochondrial impairment and cardiac dysfunction in obesity. Although glucagon-like peptide-1 receptor agonists (GLP-1RAs) exhibit cardioprotective properties, their effects on ALCAT1-mediated CL remodeling in obesity-induced myocardial injury remain unclear. Male C57BL/6 mice fed a high-fat diet (HFD) or standard diet (STD) for 12 weeks received liraglutide (200 μg/kg/day) or saline during the last 4 weeks. Cardiac function was evaluated by echocardiography; CL content was quantified using LC-MS, and myocardial alterations were assessed through histological and protein analyses. In HFD-fed mice, cardiac lipid accumulation, left ventricular hypertrophy, and myocardial collagen deposition were observed. Additionally, these mice exhibited reduced CL content, altered CL aliphatic chain composition, and upregulated ALCAT1 expression. In contrast, liraglutide treatment significantly increased total CL content, modified CL acyl chain composition, and downregulated ALCAT1 expression. Mechanistically, liraglutide activated the PI3K/AKT pathway via GLP-1 receptor signaling, attenuated oxidative stress markers (3-nitrotyrosine, Rac1 activation), and improved mitochondrial dynamics by reducing DRP1-mediated fission. These results demonstrate that liraglutide mitigates obesity-induced cardiac dysfunction by suppressing ALCAT1-driven CL remodeling, enhancing mitochondrial homeostasis, and reducing oxidative stress. This study elucidates the cardioprotective mechanisms of liraglutide and highlights its therapeutic potential for obesity-related cardiomyopathy.