Reversible compromise of physiological resilience by accumulation of heteroplasmic mtDNA mutations

Abstract

Somatically acquired mitochondrial DNA (mtDNA) mutations accumulate with age, but the mechanisms and consequences of this accumulation are poorly understood. Here we show that transient injuries induce a burst of persistent mtDNA mutations that impair resilience to future injuries. mtDNA mutations suppressed energy-intensive nucleotide metabolism. Repletion of adenosine, but not other nucleotides, restored adenosine triphosphate generation, which required a nuclear-encoded purine biosynthetic enzyme, adenylate kinase 4 (AK4). Analysis of 369,912 UK Biobank participants revealed a graded association between mutation burden and chronic kidney disease severity as well as an independent increase in the risk of future acute kidney injury events (P < 10^-7). Heteroplasmic mtDNA mutations may therefore reflect the cumulative effect of acute injuries to metabolically active cells, impairing major functions in a fashion amenable to nuclear-controlled purine biosynthesis.