A Jacksonville scientist has written a study that offers new
information about a substance seen in the brain and blood of
people with Alzheimer's disease.
Steven G. Younkin, director of research at Mayo Clinic
Jacksonville, collaborated with other researchers on the study,
which has been published in the August issue of Nature Medicine.
Scientists have known that one of the earliest changes in the
brains of people with Alzheimer's is an accumulation of a
substance called amyloid beta protein 42 (ABeta42).
That has been true of the 1 percent of Alzheimer's patients who
have an inherited, earlyonset form of the disease, and the 99
percent with the noninherited form.
The study follows a string of research on the inherited forms
of the disease, which showed that mutations in one gene, the APP
gene, increased the secretion of ABeta42.
The study showed there was also increased secretion of ABeta42
in Alzheimer's patients with mutations in two other genes, the
presenilin 1 and presenilin 2 genes.
In essence, the study adds important evidence to support the
view that the appearance of ABeta42 is a pre-cursor to
Alzheimer's and not an aftereffect, Younkin said.
"It's a big advance," he said.
The study also suggests that a good way to attack Alzheimer's
is to develop drugs that prevent ABeta42 from accumulating,
Some pharmaceutical companies are trying to develop compounds
to do that, though those drugs are early in their development,
Younkin said. …