Mitochondrial Dysfunction as a Central Hub of Aging: From Molecular Cascades to Inter-Organ Communication Networks

: Background: Mitochondrial dysfunction serves as a fundamental driver of the aging process, precipitating progressive functional decline through complex molecular cascades. Summary: This review elucidates the core mechanisms underpinning this dysfunction, including reactive oxygen species (ROS)-induced redox imbalance, mitochondrial DNA (mtDNA) damage accumulation, impaired mitophagy, and metabolic reprogramming. Crucially, we examine how mitochondria act as signaling hubs for inter-organ crosstalk. Through the secretion of mitokines (e.g., FGF21, GDF15) and the release of damage-associated molecular patterns (DAMPs), dysfunctional mitochondria trigger chronic inflammation via the cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) and NLRP3 inflammasome (NLRP3) pathways, actively driving systemic aging within the skeletal muscle-brain and adipose/liver-cardiovascular axes. Additionally, this paper synthesizes current therapeutic interventions, ranging from lifestyle modifications and nicotinamide adenine dinucleotide (NAD+) precursors to frontier technologies like mitochondrial transplantation and gene editing. Key Messages: While promising in animal models, clinical translation of these interventions is currently hindered by limited long-term safety data and evidence gaps. Therefore, mitochondria-targeted studies incorporating integrated multi-organ phenotyping are urgently required to establish robust strategies for extending human healthspan.