Researchers find enzyme associated with Alzheimer's

In this story: Disease afflicts 4 million Americans 5-year search RELATED STORIES, SITES

From Medical Correspondent Eileen O'Connor

WASHINGTON (CNN) -- Scientists say they have identified an enzyme linked to the production of protein plaques in the brain associated with Alzheimer's disease, according to an article published this week in the journal Science.

The plaques are thought to kill neurons, causing the neurological degeneration found in Alzheimer's patients.

Disease afflicts 4 million Americans

Company's stock split  just before report On the eve of the publication of the article, Amgen announced strong third-quarter financial results, a stock split and a $2 billion stock repurchase plan. The two-for-one split of the company's common stock will be in the form of a 100 percent stock dividend, to be distributed November 19 to stockholders on record as of November 5, 1999.

Also Alzheimer's vaccine seen as treatment, not cure

Alzheimer's, which affects about 4 million people in the United States, including former President Ronald Reagan, starts with memory loss and progresses to profound dementia and death.

The plaques are created when a protein called APP is cleaved, or chopped, by two enzymes: Beta-secretase and gamma- secretase.

Researchers at Amgen, a biotechnology company based in Thousand Oaks, California, reported Thursday they have identified beta-site APP-cleaving enzyme (BACE) as a protein of a gene found in healthy patients and those with Alzheimer's.

5-year search

For five years, scientists have tried to identify and locate the source of beta-secretase or gamma-secretase. The hope has been to develop a drug to inhibit production of the enzymes and thereby stop the plaques believed to cause brain damage in Alzheimer's patients.

Amgen would not comment on any progress the company may have made in developing such an inhibitor. But the firm said that even if the enzyme causes the protein plaques to form, a commercially available drug would be at least seven years off.

One expert at the National Institute on Aging cautioned that there are several theories as to how to inhibit the production of the protein plaques in the brain associated with Alzheimer's.

Scientists involved in the report said there is no guarantee that inhibiting the production of b-secretase will inhibit the production of the protein plaques.

Reuters contributed to this report.

RELATEDS AT :

Alzheimer's Disease

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RELATED SITES:

Amgen Home Page
Assessing your risk for Alzheimer's disease
Alzheimer's Association

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