The defect appears to be a mutation in the gene responsible for producing superoxide dismutase, or SOD, a potent free radical scavenger. The defective gene apparently allows the unchecked creation of free radicals, which have been linked in the past to tissue damage resulting from aging, Parkinson's and Alzheimer's disease and other conditions. This association of the gene with Lou Gehrig's disease provides the most convincing scientific evidence to date that free radicals cause damage in the body. It al so boosts efforts to find ways of slowing down the aging process, possibly through the use of vitamins or drugs.
ALS strikes about one person in 100,000, generally arising after age 50. Although scientists have known for nearly a century that nerve cell death is the essential step in ALS, they have known virtually nothing about what leads to that event. The new findings will help unravel the complicated - and apparently very drawn out - chain of events culminating in ALS.
The defective gene was found in a group of families with hereditary ALS, a rare form that accounts for about 10 percent of all ALS cases. The genetic mutation surprised its discoverer's because it occurs in a protein found in all human cells. ALS, on the other hand, is characterized not by widespread damage to numerous organs but by the degeneration of a highly specific region of the spinal cord.
ALS gradually destroys brain and spinal cord nerve cells called motor neurons, which control the body's muscles. It does not affect nerve cells of the mind and does not cause pain. Many ALS patients die within five years of diagnosis due to complications of the disease that robs the body of life while leaving the mind intact, Others, such as British physicist Stephen Hawking, have lived with the disease for decades.
Free radical damage is most often seen in acute illnesses, such as strokes or heart attacks, in which blood flow to living tissues is cut off or greatly reduced. Although researchers have long speculated that free radicals might play a role in some brain disorders, ALS had not been high on the list of possible candidates. "One of the reason we find ourselves wide-eyed and really excited is that we had not really taken the idea seriously," said Robert H. Brown Jr., one of the 32 authors of the paper.
"We are very excited by this discovery because of its far-reaching implications," said Dr. Gene Cohen, acting director of the National Institute on Aging, in a statement. "This newly found link with ALS furthers the notion that we may be able to slow the rate of normal aging and certain age-related diseases."
The researchers said they plan to launch studies of drugs or vitamins that could eliminate or block the creation of free radicals. According to the scientists, immediate research will focus on well known antioxidants such as vitamins A, E and C.
|Web Orders||Toll-Free (USA/Canada)||Customer Service||Fax|