Diabetic cardiomyopathy (DbCM) is an important contributor to heart failure (HF) in diabetes, occurring independently of other cardiovascular risk factors. Accumulating evidence demonstrates that cardiac lipotoxicity is a key driver of the onset and progression of DbCM and HF. Myocardial lipid homeostasis is coordinated by multiple transcriptional regulations, signaling pathway activation, and endoplasmic reticulum-mediated management involved in lipid metabolism. In DbCM, unbalanced fatty acid (FA) influx, handling, storage, and utilization initiates lipid overload, accumulation of toxic lipid intermediates (e.g., diacylglycerols and ceramides), and activation of maladaptive response. Notably, these lipid intermediates amplify reactive oxygen species (ROS) generation, which serves as a critical link between lipotoxic signaling and mitochondrial dysfunction by promoting electron leak, mitochondrial damage, and activation of inflammatory and cell-death pathways. These processes converge on adverse remodeling and contractile impairment, accelerating DbCM progression. This review integrates mechanistic and translational evidence linking dysregulated lipid handling to DbCM and discusses the potential therapeutic strategies that target lipid abnormalities.

Ceramides are central bioactive sphingolipids that regulate diverse cellular processes, including membrane organization, energy metabolism, and stress signaling. Emerging evidence has implicated that ceramide dysregulation is associated with the onset and progression of heart failure. This review introduces the understanding of ceramide metabolism, focusing on its biosynthesis, and functional roles in cardiomyocytes. In addition, the contribution of systemic ceramides derived from circulating lipoproteins and peripheral tissues to cardiovascular risk is also discussed. In parallel, it is highlighted that cardiomyocyte-intrinsic ceramide synthesis plays physiological and pathological roles in the heart. Particularly, excessive ceramide accumulation is detrimental for cardiac function, through multiple mechanisms, such as lipotoxic effects, mitochondrial impairment, inflammation, and cell death. The current review discusses the potential diagnostic and therapeutic strategies targeting ceramide metabolism, as well as the open questions about ceramide association with heart disease.

Increased consumption of ultra-processed foods (UPFs) is a risk factor for metabolic disorder–associated heart failure (HF). Here, we demonstrate that UPF-induced calpain-1 aggravated oxidative stress, thereby increasing high mobility group box 1–mediated (HMGB1-mediated) myocardial inflammation, which contributes to cardiac dysfunction. After illustrating the dysregulated inflammatory pathways in human and murine hearts upon metabolic stress, we revealed an increase in calpain-1 alongside profound oxidative stress and inflammation in the failing myocardium. Mechanistically, in neonatal rat cardiomyocytes and human induced pluripotent stem cell–derived cardiomyocytes, HMGB1 was upregulated by calpain-1 and reactive oxygen species (ROS) upon stress of saturated and trans fatty acids. Consequently, HMGB1 promoted a proinflammatory response in macrophages. In contrast, inhibition of calpain or ROS efficiently repressed HMGB1 in cardiomyocytes. Therapeutically, either recombinant adeno-associated virus 9–delivered inhibitor of calpain-1 or its pharmacological inhibitor attenuated ROS and HMGB1-induced inflammation in the myocardium and mitigated HF in both male and female mice fed with an ultra-processed diet. Collectively, we have demonstrated the effects of suppressing calpain-1 and oxidative stress on alleviating myocardial inflammation via blockage of HMGB1 and cardiac dysfunction. The results provide a promising therapeutic strategy for preventing or treating HF in metabolic disorders.