Fewer Calories May Slow Alzheimer's
restrictive diet in mice reduces the build-up of a substance linked
to memory loss. But can the findngs be applied to humans?
Restricting the diets of mice reduces the build-up of plaques in
the brain that are linked to Alzheimer's disease, according to a
With obese people generally considered to be at a higher risk
for developing Alzheimer's, the research raises questions about
whether the findings are potentially applicable to humans.
"This is the first indication that modest changes in the normal
diet can slow some aspects of Alzheimer's disease," said Caleb
Finch, co-author of the study published in the online version
of the journal Neurobiology of Aging.
"But that is far and away yet to be proven for humans. It's
a big jump to say that what's true for a mouse in a cage is relevant
to people living in our complex world," Finch said.
In the study, conducted with collaborators at the University
of South Florida in Tampa, researchers used mice whose DNA had
been altered with human genes from two families with early onset
The mice were then split into two groups as young adults: one
that could eat all it desired ("ad libitum") and the other that
had its food intake reduced by 40 percent over a four-week period
The researchers were looking specifically at the formation of
plaques caused by a build-up of the fiber-like substance called
Made up of proteins and polysaccharides, amyloid plaques are
deposited in the brain during Alzheimer's disease. Specifically,
plaques accumulate in the hippocampus and frontal cortex of Alzheimer's
sufferers - areas responsible for memory.
In the diet-restricted mice, both the amount and size of plaque
was about 50 percent less than in mice that ate as much as they
"The power of this study is that two different sets of [human]
family mutations were equally sensitive to the effect of diet
and slowing the Alzheimer's-like change," said Finch, holder of
the ARCO-William F. Kieschnick Chair in the Neurobiology of Aging
The next goal is to find out why diet restriction has such profound
and rapid effects, Finch said.
"We are going to look into the details of metabolism to try
and isolate which of the consequences of diet restriction is at
work," Finch said. "Is it the blood glucose? Is it the lowered
insulin? Those are two targets."
The other USC researchers on this study were Nilay V. Patel,
a former USC postdoc who is now a staff scientist at City of Hope
Medical Center, and Todd E. Morgan, a research assistant professor
in the Andrus Gerontology Center at USC.
The researchers at the University of Southern Florida are Marcia
Gordon, Karen E. Connor, Robert A. Good, Robert W. Engelman, Jerimiah
Mason and David G. Morgan
Reference Source 125
December 17, 2004