Exposure to Oxidative Stress Might Prolong Life
Exposing the body to small amounts of oxidative stress may promote longevity according to the results of a new study. The findings are contrary to the widely held notion that consuming antioxidants delays the aging process and increases lifespan. New research shows that oxidative stress may be disease protective and lead to a longer life.
The research, led by Trey Ideker, PhD, chief of the Division of Genetics in the Department of Medicine at UC San Diego's School of Medicine found that human genes adapt to low-level exposure to oxidative stress caused by hydrogen peroxide – a major contributor to cellular oxidation.
Ideker, along with Ryan Kelley, first author of the study, looked at how cells adapt to the stress of hydrogen peroxide by converting it to oxygen and water by pre-treating the cells with small amounts of hydrogen peroxide, then subjecting the cells to high doses. The process allowed the scientists to observe how cells adapt.
Next, the research team systematically removed genes to find out which ones adapted to oxidative stress, observing each gene’s response to oxidation. They discovered that a new process called Mga2 is essential for gene adaption, and only occurs when cells are exposed to low levels of oxidative stress.
The researchers say that exposure to reactive oxygen species (ROS) seems to offer health benefits by protecting the body from acute exposure through adaptation. "It may be that adaption to oxidative stress is the main factor responsible for the lifespan-expanding effects of caloric restriction," said Ideker. Calorie restriction is shown to raise levels of ROS in recent studies.
Attempts to rid the body of free radicals from oxidative stress may actually be counterproductive for delaying the aging process. …”our study suggests why humans may actually be able to prolong the aging process by regularly exposing our bodies to minimal amounts of oxidants”, explains Dr. Ideker. The new study shows that exposure to oxidative stress may actually prolong life; contrary to popular belief that exposure to oxidative stress accelerates the aging process.
Published in the May 2009 Issue of PLoS Genetics