We found hopeful news last week
in a study hinting at a way to block amyloid beta proteins in the brain, protecting against Alzheimers, but this week we are reminded that everything, especially in the brain, comes back to equilibrium. Studying fruit flies, scientists have found that a major role of Amyloid Precursor Protein (APP) is to stimulate axonal arborization
(that means neurons making connections with other neurons, which is critical to all brain functions).
So it seems, the author points out, that a protein which allows our brains to function as well as they do in our youth, ends up causing our decline in old age. But only in some people. It would be easy to hypothesize, given this paradox, that more intelligent people might be more prone to Alzheimers later in life; alas, I don't think the data have bourne this out. Still, it's fascinating stuff.