Abstract
Intercellular mitochondrial transfer is recognized as a central mechanism that shapes redox homeostasis, metabolic plasticity, and cellular resilience across multiple tissues. Through tunneling nanotubes (TNTs), extracellular vesicles (EVs), gap junction channels (GJCs), and cell fusion, mitochondria move between donor and recipient cells to restore bioenergetic capacity, buffer oxidative stress, and tune redox-sensitive signaling networks. Recent work has begun to clarify the regulatory framework governing donor-recipient specificity, cargo selection, and the stress-activated cues that trigger organelle exchange. Mitochondrial transfer also exerts distinct, context-dependent influences on disease trajectories. It mitigates injury in neurological damage, ischemia-reperfusion conditions, immune dysfunction, aging, and inflammatory pain, largely by reprogramming mitochondrial function and reactive oxygen species (ROS) dynamics. Conversely, in cancer, mitochondrial acquisition enhances metabolic flexibility, invasiveness, and resistance to therapy. Current therapeutic approaches, including mitochondrial transplantation, EV-based delivery systems, and mitochondria-enhanced immune cells, highlight the translational potential of manipulating mitochondrial exchange, yet face challenges such as mitochondrial fragility, inefficient targeting, and immunogenicity. Deeper mechanistic insight into how mitochondrial transfer remodels redox signaling and metabolic adaptation will be essential for converting this biological process into next-generation organelle-level interventions for redox-driven disorders.