It is one of the big scientific mysteries of Alzheimer’s disease: Why do some people whose brains accumulate the plaques and tangles so strongly associated with Alzheimer’s not develop the disease?
Now, a series of studies by Harvard scientists suggests a possible answer, one that could lead to new treatments if confirmed by other research.
The research, published on Wednesday in the journal Nature, focuses on a protein previously thought to act mostly in the brains of developing fetuses. The scientists found that the protein also appears to protect neurons in healthy older people from aging-related stresses. But in people with Alzheimer’s and other dementias, the protein is sharply depleted in key brain regions. REST, a gene regulator that switches off certain genes, is primarily known to keep fetal neurons in an immature state until they develop to perform brain functions, said Dr. Bruce A. Yankner, a professor of genetics at Harvard Medical School and the new study’s lead author. By the time babies are born, REST becomes inactive, he said, except in some areas outside the brain like the colon, where it seems to suppress cancer.
Dr. Yankner’s team is looking at REST in other neurological diseases, like Parkinson’s. He also has thoughts about a potential treatment, lithium, which he said appears to stimulate REST function, and is considered relatively safe.
But he and other experts said it was too early. “I would hesitate to start rushing into lithium treatment” unless rigorous studies show it can forestall dementia, said Dr. John Morris, an Alzheimer’s researcher at Washington University in St. Louis.
http://www.nytimes.c...ds.html?hp&_r=0
