A Different View of Alzheimer's and Blood Flow
Researchers how produced evidence suggesting that reduced blood flow to the brain prevents amyloid beta from being carried away, thereby worsening the progression of Alzheimer's - which explains why exercise seems to help resist this age-related condition. Here is a different view of why reduced blood flow is bad, and a reminder that Alzheimer's a complex, many-faceted degeneration: "when the brain doesn't get enough sugar glucose - as might occur when cardiovascular disease restricts blood flow in arteries to the brain - a process is launched that ultimately produces the sticky clumps of protein that appear to be a cause of Alzheimer's. [Researchers] discovered a key brain protein is altered when the brain has a deficient supply of energy. The altered protein, called elF2alpha, increases the production of an enzyme that, in turn, flips a switch to produce the sticky protein clumps. ... What we are talking about here is a slow, insidious process over many years where people have a low level of cardiovascular disease or atherosclerosis in the brain. It's so mild, they don't even notice it, but it has an effect over time because it's producing a chronic reduction in the blood flow."
Link: http://www.eurekalert.org/pub_releases/2008-12/nu-bsa122308.php