TAMPA, Fla., Sept. 12 New research now showsfor the first time that, of all lifelong activities, only a high level ofmental or cognitive activity protects against the devastating memory loss ofAlzheimer's disease. High levels of social or physical activity are notenough.
Byrd Institute researchers raised Alzheimer's mice from young adulthoodthrough old age in one of four housing environments -- high social activity,high physical activity, high cognitive activity, or a single-housing controlenvironment. When the researchers tested the mice in a battery of memorytasks in old age, only the mice given a lifelong high level of cognitiveactivity were protected against memory impairment. In fact, these "highcognitive activity" mice performed as well as normal mice that do not developAlzheimer's disease. In sharp contrast, the Alzheimer's mice raised in one ofthe other three environments performed poorly in multiple memory tasks.
Not only was memory protected in Alzheimer's mice by a high level ofcognitive activity, but brain levels of the abnormal protein beta-amyloid weresubstantially reduced. This protein, thought to be key for Alzheimer'sdevelopment, remained at soaring levels in the brains of Alzheimer's miceraised in social or physical activity environments. Moreover, the researchersfound that only the Alzheimer's mice raised with high cognitive activity hadan increase in connections between brain cells. Alzheimer's mice raised inone of the other three housing environments had much fewer connections betweentheir brain cells.
The new study is published in the Neurobiology of Learning and MemoryJournal.
"Our results call into question the earlier human studies suggestingsocial or physical activity provides protection against Alzheimer's," said Dr.Gary Arendash, the lead researcher on the study.
"Alzheimer's begins in the brain several decades before any symptoms showup," said Dr. Arendash. "That means adults in their forties and fifties needto make lifestyle choices now to decrease their risk of getting Alzheimer'sdisease later."Read a more detailed news release at:www.byrdinstitute.org/news/institute-news/09-12-07.aspx Contact: Jennifer Whelihan Communications Liaison 813.319.4115 813.951.8973 [email protected]
SOURCE The Byrd Alzheimer's Institute