Diabetic Cardiomyopathy: Unraveling the Molecular Architecture beyond Hyperglycemia – A Narrative Review

Diabetic cardiomyopathy (DCM) is an increasingly recognized complication of diabetes mellitus, characterized by structural and functional changes in the myocardium independent of coronary artery disease and hypertension. Conventionally, hyperglycemia has been considered the principal pathogenic driver of DCM. However, growing evidence suggests that DCM arises from a multifactorial interplay of molecular mechanisms that extend far beyond glucose toxicity. This review aims to explore the complex molecular architecture underlying DCM, focusing on nonhyperglycemic pathways that contribute to cardiac dysfunction in diabetic patients. We highlight key mechanisms such as insulin resistance-induced metabolic remodeling, mitochondrial dysfunction leading to impaired adenosine triphosphate (ATP) production and excessive reactive oxygen species generation, chronic inflammation mediated by nuclear factor kappa-B and NLRP3 inflammasome activation, and maladaptive extracellular matrix remodeling driven by profibrotic mediators such as transforming growth factor-beta and galectin-3. Additional emphasis is placed on the roles of endoplasmic reticulum stress, defective autophagy, and epigenetic modifications, including microRNAs and histone acetylation patterns that collectively modulate cardiomyocyte survival, contractility, and remodeling. Understanding these diverse molecular contributors is essential for improving early diagnosis, identifying novel biomarkers, and developing targeted therapeutic strategies to prevent or reverse myocardial damage in diabetes. Recognizing DCM as a distinct, multifactorial entity may facilitate precision medicine approaches tailored to the underlying pathobiology in diabetic patients.