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Scientists find a worm enzyme that helps extend life JEFF DONN, Associated Press Writer Thursday, May 13, 1999 URL: http://search.go2net.com/crawler?general=alzheimer+worm&method=0&target=® ion=0&rpp=20&timeout=5&hpe=10 (05-13) 06:51 PDT A cell-protecting enzyme needed for long life in worms may help in finding better treatments for Alzheimer's and other human diseases associated with aging, scientists say. The finding of the enzyme reported today in the journal Nature ``gets us closer to understanding what's involved in the aging process and where we can intervene,'' said Anna McCormick, a biochemist at the National Institute on Aging. Researchers led by biologist Martin Chalfie at Columbia University studied a nearly microscopic roundworm known as Caenorhabditis elegans. When it is well fed, it survives only about three weeks, but it can withstand food shortages in a larval state for at least two months. Several genes in this worm were already linked to the larva's longer life, but their mechanism wasn't known. The research team from Columbia and Dartmouth College identified an enzyme known as a cytosolic catalase that seems to act as a central agent in allowing some worms to live longer. When the normal gene that makes the enzyme, ctl-1, is removed, the worms die sooner. The next step is to determine whether a similar enzyme exists in humans. The researchers argue that cytosolic catalase allows longer life by performing a function it was already known to serve: blocking cell damage caused by oxygen compounds. Such oxidative damage -- analogous to metal rusting -- has been implicated in human aging and diseases like Alzheimer's, Lou Gehrig's and Parkinson's. Vitamin E, an antioxidant, is now used to prevent heart attacks and treat Alzheimer's in some patients. The discovery of the catalase gene bolsters the theory that oxidative damage is central to both aging and its diseases. The worm gene ``should give impetus to people working on the human genes to try to look for things like this,'' Chalfie said. It may eventually be possible to protect human nerve cells by boosting catalase with a drug, McCormick suggested. Siegfried Hakimi, a McGill University biologist who also studies life span in roundworms, said researchers should now seek to establish if higher levels of cytosolic catalase alone will make worms live longer, not just block cell damage. Tom Johnson, a University of Colorado geneticist who also works with roundworms, cautioned that their life-extending mechanisms may ultimately have limited relevance to human disease. But he said researchers have made roundworms live five times longer with genetic manipulations. Johnson thinks such work suggests that people can also live longer with the right drug -- or mix of drugs -- in the future. ``I'm not sure how much of a magic bullet it will be. I think it will be a variety of bullets,'' he said. "There can be no happiness if the things we believe in are different from the things we do." - Author Unknown "There can be no happiness if the things we believe in are different from the things we do." - Author Unknown