Washington, April 17: A pathway that protects cells when oxygen levels dip also plays a role in longevity and resistance against old-age diseases, according to a new study.
A cell's protective reaction to a drop in oxygen is called the hypoxic response.
University of Washington (UW) researchers have found that nematode worms live longer if their genetic make-up permits their cells to turn on the hypoxic response under normal oxygen conditions.
Not only do these worms live longer, their cells are relatively free from the toxic proteins that accumulate and clump together as an animal ages.
Matt Kaeberlein, study co-author, said that defining cellular mechanisms that prevent accumulation of these proteins may open the way to better treatment of devastating old-age diseases.
Toxic protein aggregations, he explained, are seen in the brain cells of those with Alzheimer's disease, Huntington's disease, and several other degenerative conditions that afflict the elderly.
Researcher Katy Steinkraus and others uncovered the life-extending role of the hypoxic response while studying the mechanism by which dietary restriction slows ageing in nematodes.
Dietary restriction has been shown to increase life span in many different organisms, including worms, flies and mice. Kaeberlein's group had previously found that dietary restriction also protects against toxic protein aggregation in nematode models of Huntington's and Alzheimer's diseases.
To their surprise, however, genetic experiments mapped the hypoxic response to a previously unknown longevity pathway, different from dietary restriction, said a UV release
"The research findings suggest that the hypoxic response promotes longevity and reduces the accumulation of toxic proteins by a mechanism that is distinct from both dietary restriction and insulin-like signalling. It appears to be an alternative pathway," Kaeberlein said.
First Published: Friday, April 17, 2009, 00:00