Reevaluating the Role of Mitochondrial DNA Mutations in Aging

Mitochondria, the energy-producing organelles within our cells, contain their own DNA known as mitochondrial DNA (mtDNA). Unlike nuclear DNA, mtDNA is more susceptible to mutations over time, leading to the longstanding hypothesis that these mutations accumulate with age and cause mitochondrial decline, thereby contributing to the aging process—the so-called mitochondrial theory of aging.

However, recent research challenges this widely accepted idea. A study conducted by scientists at the University of Tsukuba has demonstrated that mitochondrial respiratory function—critical for cell energy production—remains intact even in mice that have accumulated extensive mtDNA mutations similar to those found in premature aging models. This indicates that the buildup of mtDNA mutations alone may not be the direct cause of mitochondrial dysfunction associated with aging.

The findings, published in the journal Aging Cell, encourage scientists to reconsider the link between mtDNA mutations and aging. They suggest that other factors or mechanisms might play a more significant role in mitochondrial decline and the aging process.

The research team plans to continue exploring how various mutations within mtDNA influence aging symptoms, aiming to further understand the complex relationship between mitochondrial health and age-related deterioration. This study highlights the need to look beyond mtDNA mutations when investigating the causes of aging and developing potential interventions.

Source: https://medicalxpress.com/news/2025-05-mitochondrial-dna-mutation-accumulation-factor.html