Roanoke Times
Copyright (c) 1995, Landmark Communications, Inc.
DATE: TUESDAY, May 29, 1990 TAG: 9005290130
SECTION: NATIONAL/INTERNATIONAL PAGE: A2 EDITION: METRO
SOURCE: The New York Times
DATELINE: LENGTH: Medium
In a series of papers published over the last few weeks in the journal Science and The Proceedings of the National Academy of Sciences, and in reports that will be presented at a meeting in Toronto in July, scientists are casting important new light on the strange protein fragment, known as beta amyloid, and how a few small errors in protein metabolism may spawn a chain reaction of cell death.
Although some researchers reserve judgment, others predict the insights could result in new therapies against the disease.
The latest work strongly suggests that the abnormal accretion of the protein fragments into stiff, rope-like patches throughout the brain is either a seminal event or one of the significant steps in the development of Alzheimer's.
Many of the researchers believe that these amyloid plaques destroy the surrounding brain tissue, thereby contributing to memory loss, confusion and other hallmarks of the progressive dementia.
Although researchers have known for some time that the plaques accumulate in the brains of people with Alzheimer's disease, they are now able to track the biochemical stages of their formation.
They have gained new clues into the role of the normal protein from which amyloid pieces break off, and they are learning how the presence of just a few protein tatters in the brain may trigger production of beta-amyloid plaques.
"In the past year or two, I have seen a lot of my colleagues who were initially skeptical become convinced that amyloid deposits are important" to Alzheimer's disease, said Dr. Blas Frangione, professor of pathology and an amyloid researcher at New York University Medical Center.
Researchers first were drawn to study beta amyloid about six years ago, following the discovery of microscopic patches of what looked like hemp fibers in the autopsied brains of Alzheimer's patients.
When subjected to biochemical manipulations, the plaques proved surprisingly resistant to degradation. "If you could hold them in your hand, they would feel like Brillo pads," said Dr. Ralph Nixon, associate professor of psychiatry and an amyloid expert at Harvard Medical School and McLean Hospital in Boston.
by CNB