TUESDAY, Feb. 23, 2021 — Researchers may have uncovered a key reason some people remain sharp as a tack into their 80s and 90s: Their brains resist the buildup of certain proteins that mark Alzheimer’s disease.
The study focused on what scientists have dubbed “super agers” — a select group of older folks who have the memory performance of people decades younger.
Compared with older people who had average brain power, super agers showed far less evidence of “tau tangles” in their brains, the researchers found.
Tau is a protein that, in healthy brain cells, helps stabilize the internal structure. But abnormal versions of tau — ones that cling to other tau proteins — can develop as well.
In people with Alzheimer’s, the brain is marked by a large accumulation of those tau tangles, as well as “plaques,” which are clumps of another protein called amyloid.
For years, amyloid plaques have gotten most of the attention as a potential target for Alzheimer’s treatment, said researcher Tamar Gefen, who led the new study.
But a body of evidence tells a different story: It’s the buildup of tau — not amyloid — that correlates with a decline in memory and thinking skills, said Gefen, an assistant professor at Northwestern University Feinberg School of Medicine, in Chicago…