Mitochondrial quality control in health and disease: mechanisms and therapeutic targets

Mitochondria are essential for cellular homeostasis, integrating various signals to control key cellular functions such as metabolism, apoptosis, inflammation, cell proliferation and redox balance. Given their multifaceted functions, it is not surprising that mitochondrial dysfunction has been implicated as a key contributor to the pathogenesis of numerous human diseases. Consequently, preserving mitochondrial integrity and functionality is vital for overall organismal health. Mitochondrial health is safeguarded by a sophisticated and tightly regulated network of quality control systems. These include mitochondrial proteostasis, which ensures proper protein folding and degradation; mitochondrial biogenesis, which governs the synthesis of new mitochondria; mitochondrial dynamics, encompassing fusion and fission processes; and mitophagy, the selective autophagic removal of damaged mitochondria. Additionally, these core systems are intricately connected to other crucial mitochondrial processes, such as the maintenance of mitochondrial DNA integrity, the regulation of cristae architecture, and the control of mitochondrial permeability transition, all of which are indispensable for optimal mitochondrial performance. Preclinical and clinical studies consistently demonstrate a strong link between impairments in these quality control mechanisms and both aging and the development of a wide spectrum of diseases. These include cancer, metabolic disorders, cardiovascular conditions, neurodegenerative diseases and autoimmune pathologies. In this review, we explore the different facets of mitochondrial quality control and discuss their implications in disease progression and aging. Furthermore, we highlight recent advances in interventions and therapies aimed at modulating mitochondrial quality control, providing an overview of their potential to mitigate disease burden and promote healthy aging.