Forget the antioxidants? McGill researchers cast doubt on role of free radical...( This release is available in a href...)
This release is available in French.
For more than 40 years, the prevailing explanation of why we get old has been tied to what is called oxidative stress. This theory postulates that when molecules like free radicals, oxygen ions and peroxides build up in cells, they overwhelm the cells' ability to repair the damage they cause, and the cells age.
An industry of "alternative" antioxidant therapies -- such as Vitamin E or CoQ10 supplements in megadose format --has sprung up as the result of this theory. However, clinical trials have not shown that these treatments have statistically significant effects.
And now researchers at McGill University, in a study published in the February issue of the journal PLoS Genetics, are calling the entire oxidative stress theory into question. Their results show that some organisms actually live longer when their ability to clean themselves of this toxic molecule buildup is partially disabled. Collectively, these molecules are known as reactive oxygen species, or ROS for short.
Dr. Siegfried Hekimi of McGill's Department of Biology, said most of the evidence for the oxidative stress theory is circumstantial, meaning oxidative stress could just as easily be a result of aging as its cause.
"The problem with the theory is that it's been based purely on correlative data, on the weight of evidence," explained Hekimi, McGill's Strathcona Chair of Zoology and Robert Archibald & Catherine Louise Campbell Chair in Developmental Biology. "It is true that the more an organism appears aged, whether in terms of disease, or appearance or anything you care to measure, the more it seems to be suffering from oxidative stress".
"This has really entrenched the theory," he continued, "because people think correlation is causation. But now this theory really is in the way of progress."
<'/>"/>
| Contact: Mark Shainblum mark.shainblum@mcgill.ca 514-398-2189 McGill University Source:Eurekalert |
Related biology news :
1. Dont forget the vitamin A when working with its carrier protein
2. Fighting Aussie yabbies dont forget a face -- new research by the University of Melbourne
3. When accounting for the global nitrogen budget, dont forget fish
4. MUHC and McGill scientists explain genetic disease first discovered in Quebec 24 years ago
5. Key to curing obesity may lie in worms that destroy their own fat: McGill researchers
6. Boost from McGill, Gates Foundation helps Africans control pharma research
7. McGill conference on Global Food Crisis draws impressive list of international participants
8. Oceanographer Dennis J. McGillicuddy, Jr. receives 34th annual Rosenstiel Award
9. Tiny genetic differences have huge consequences: McGill researchers
10. Type 1 diabetes triggered by lazy regulatory T-cells: McGill researchers
11. 12 McGill researchers awarded Canada Research Chairs
| Copyright © 2003-2009 Bio-Medicine. All rights reserved. ABOUT | CONTACT US | DISCLAIMER | PRIVACY POLICY | TERMS AND CONDITIONS |  |