February 14, 2014
The Lifespan Of The Worm Predicted With Accuracy In New Study
Lee Rannals for redOrbit.com - Your Universe Online
Scientists claim they have found a way to accurately predict the lifespan of a worm, meaning fortune tellers should be updating their LinkedIn profiles pretty soon.Researchers, publishing a paper in the journal Nature, say they have found a way to determine an organism’s lifespan by looking at the bursts of activity in the mitochondria, which is part of the cell which generates energy.
“Mitochondrial flashes have an amazing power to predict the remaining lifespan in animals,” study lead Meng-Qiu Dong, a geneticist who studies ageing in the Caenorhabditis elegans worm at the National Institute of Biological Sciences in Beijing, said in a statement. “There is truth in the mitochondrial theory of aging.”
The worms in the study usually live for about 21 days and are at their peak of reproductive fitness at just three days old. The team found that worms with low mitoflash activity lived longer, while those with high mitoflash activity died before 21 days.
“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,” the authors wrote in the journal. “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.”
According to the study, worms carrying a genetic mutation known to extend life to 39 days exhibited fewer mitoflash bursts than genetically healthy worms. The same pattern was seen when the researchers exposed the worms to short periods of starvation and heat shock.
The researchers said the most shocking finding came when Dong treated a long-lived worm to increase its production to reactive oxygen molecules. This technique shortened the worm’s life and increased the rate of mitoflashes.
“These results demonstrate that the day-3 mitoflash frequency is a powerful predictor of C. elegans lifespan across genetic, environmental and stochastic factors,” the team wrote in the journal. “They also support the notion that the rate of aging, although adjustable in later life, has been set to a considerable degree before reproduction ceases.”