Worm study suggests that activity in mitochondria determines ageing.
Scientists have a crystal ball on their hands: bursts of activity in the energy-producing mitochondria in a worm’s cells accurately predict how long it will live.
The findings, published today in Nature1, suggest that an organism’s lifespan is, for the most part, predictable in early adulthood. Unlike other biomarkers for ageing, which work under limited conditions, these mitochondrial bursts are a stable predictor for a variety of genetic, environmental and developmental histories. “Mitochondrial flashes have an amazing power to predict the remaining lifespan in animals,” says study lead Meng-Qiu Dong, a geneticist who studies ageing in the Caenorhabditis elegans worm at the National Institute of Biological Sciences in Beijing. “There is truth in the mitochondrial theory of ageing.”
The mitochondria are organelles that power the cells of plants, animals and other eukaryotic organisms. During energy production, they produce reactive oxygen molecules, such as free radicals, that can cause stress and damage the mitochondria. Although mitochondria break down over time, the mitochondrial theory of ageing, first proposed2 in 1972, remains controversial and unproven. For instance, some long-lived organisms, such as naked mole rats, endure with high levels of oxidative damage. Nevertheless, many scientists think that mitochondria remain the primary drivers of ageing.