Mitochondrial quality control as a therapeutic target in cardiovascular disease: Mechanistic insights and future directions.

Mitochondrial dysfunction is increasingly recognized as a critical driver in the pathogenesis of cardiovascular diseases. Mitochondrial quality control (MQC) is an ensemble of adaptive mechanisms aimed at maintaining mitochondrial integrity and functionality and is essential for cardiomyocyte viability and optimal cardiac performance under the stress of cardiovascular pathology. The key MQC components include mitochondrial fission, fusion, mitophagy, and mitochondria-dependent cell death, each contributing uniquely to cellular homeostasis. The dynamic interplay among these processes is intricately linked to pathological phenomena, such as redox imbalance, calcium overload, dysregulated energy metabolism, impaired signal transduction, mitochondrial unfolded protein response, and endoplasmic reticulum stress. Aberrant mitochondrial fission is an early marker of mitochondrial injury and cardiomyocyte apoptosis, whereas reduced mitochondrial fusion is frequently observed in stressed cardiomyocytes and is associated with mitochondrial dysfunction and cardiac impairment. Mitophagy is a protective, selective autophagic degradation process that eliminates structurally compromised mitochondria, preserving mitochondrial network integrity. However, dysregulated mitophagy can exacerbate cellular injury, promoting cell death. Beyond their role as the primary energy source of the cell, mitochondria are also central regulators of cardiomyocyte survival, mediating apoptosis and necroptosis in reperfused myocardium. Consequently, MQC impairment may be a determining factor in cardiomyocyte fate. This review consolidates current insights into the regulatory mechanisms and pathological significance of MQC across diverse cardiovascular conditions, highlighting potential therapeutic avenues for the clinical management of heart diseases.