A new discovery by NIBS scientists: lifespan determined in a flash.

Feb. 13, 2014-Dr. Meng-Qiu Dong's laboratory at National Institute of Biological Sciences, Beijing (NIBS) discovered the first biomarker that can predict the effect of genetic, environmental and random factors on the lifespan of an animal. The study entitled 'Mitoflash frequency in early adulthood predicts lifespan in Caenorhabditis elegans' is published on-line in Nature yesterday.

It has been theorized for decades that mitochondria act as the biological clock of ageing, but the evidence is incomplete. Here we show a strong coupling between mitochondrial function and ageing by in vivo visualization of the mitochondrial flash (mitoflash), a frequency-coded optical readout reflecting free-radical production and energy metabolism at the single-mitochondrion level. Mitoflash activity in Caenorhabditis elegans pharyngeal muscles peaked on adult day 3 during active reproduction and on day 9 when animals started to die off. A plethora of genetic mutations and environmental factors inversely modified the lifespan and the day-3 mitoflash frequency. Even within an isogenic population, the day-3 mitoflash frequency was negatively correlated with the lifespan of individual animals. Furthermore, enhanced activity of the glyoxylate cycle contributed to the decreased day-3 mitoflash frequency and the longevity of daf-2 mutant animals. These results demonstrate that the day-3 mitoflash frequency is a powerful predictor of C. elegans lifespan across genetic, environmental and stochastic factors. Previously identified indicators of ageing and lifespan in C. elegans are only effective in mid-aged animals or require lengthy measurements. Moreover, none has a demonstrated predictive power for genetic and environmental factors. The day-3 mitoflash frequency is a unique lifespan predictor because it is an early, single-point measurement, yet effective for all classes of lifespan modifiers.

These findings also support the notion that the rate of ageing, although adjustable in later life, has been set to a considerable degree before reproduction ceases. The results are consistent with the programmed theories of aging.