Mitochondria Drive Disease and Aging — And New Therapies Are Catching Up

Mitochondria were long viewed primarily as ATP-generating organelles, but this 2025 review published in Molecular Biomedicine makes the case that they are far more — acting as central hubs for signal transduction, calcium buffering, ROS regulation, apoptosis control, and inter-organelle communication. The authors from Southwest Jiaotong University and Sichuan University synthesize current understanding of mitochondrial structure, dynamics, and disease relevance into one of the most thorough overviews published to date.

The review begins with mitochondrial architecture: the double-membrane system, the 16,569-bp circular mtDNA encoding 37 genes (13 proteins, 22 tRNAs, 2 rRNAs), and the electron transport chain (Complexes I–V) that drives OXPHOS. Crucially, mitochondria operate as a 'mitochondrial information processing system' (MIPS) — sensing metabolic, hormonal, and oxidative signals, integrating them, and producing output signals that regulate gene expression, cell cycle, and systemic physiology.

Mitochondrial dynamics — the continuous cycles of fission (driven by Drp1 and its OMM receptors Fis1, Mff, MiD49/51) and fusion (driven by Mfn1/Mfn2 for the outer membrane and OPA1 for the inner membrane) — are essential for quality control. Mitophagy, the selective autophagic clearance of damaged mitochondria, further maintains the healthy mitochondrial pool. Disruption of these processes is mechanistically linked to neurodegeneration (Alzheimer's tau pathology impairs mitophagy; Parkinson's PINK1/Parkin pathway is central to mitochondrial quality control), cardiovascular disease (mtDNA damage triggers inflammation and cholesterol accumulation), diabetes (mitochondria regulate both β-cell insulin secretion and peripheral insulin resistance), and cancer (the Warburg effect and mitochondrial metabolic reprogramming support tumor proliferation and immune evasion). Viral infections including SARS-CoV-2 directly impair mitochondrial function, worsening disease severity.

Aging receives particular attention: the review frames the age-related decline in mitochondrial function — accumulation of mtDNA mutations, reduced OXPHOS efficiency, impaired mitophagy, and increased ROS — as a central driver of frailty and disease susceptibility. This positions mitochondrial health as a core target for longevity medicine.

Therapeutically, the review catalogs four strategic areas: (1) mitochondria-targeted antioxidants (e.g., MitoQ, SkQ1) that reduce pathological ROS without abolishing signaling ROS; (2) pharmacological and genetic modulation of fission/fusion balance and mitophagy; (3) mitochondrial genome editing using tools such as mitoZFNs, mitoTALENs, and emerging mitoBEs to correct heteroplasmic mtDNA mutations; and (4) mitochondrial transplantation — delivering intact, functional mitochondria into compromised cells — which has shown early promise in cardiac and neurological injury models. The authors acknowledge that delivery specificity, off-target effects, and immunogenicity remain significant hurdles across all therapeutic approaches.