- FRIDAY, May 9 (HealthDay News) — Flavonoids, compounds found in
many fruits and vegetables, may be able to battle the ravages of
Alzheimer's disease, a new study suggests.

In experiments with mice, two flavonoids called luteolin and diosmin
reduced levels of beta-amyloid, which forms the harmful plaques that build
up in the brains of those with Alzheimer's disease.

“Our lab has been investigating beta-amyloid, which is associated with
Alzheimer's, and how we can reduce it using natural compounds,” said lead
researcher Kavon Rezai-Zadeh, from the Rashid Laboratory for Developmental
Neurobiology at Silver Child Development Center at the University of South
Florida.

The research team would like to use the two flavonoids to see if they
can reduce amyloid plaque in humans, since they believe flavonoids would
be safe and have few side effects compared with drugs that are being
developed to reduce amyloid plaque.

Rezai-Zadeh also thinks that flavonoids, which have strong antioxidant
properties, might guard against Alzheimer's. “A lot of these compounds can
be derived from the diet, and they may have preventive effects against
Alzheimer's disease,” he said. “Increasing the flavonoids in your diet may
help reduce the risk of Alzheimer's.”

“The question is, can we use these flavonoids in people that have
cognitive impairment?” Rezai-Zadeh said. “That's the million-dollar
question.”

The report was published in the May 8 online edition of the Journal
of Cellular and Molecular Medicine.

In the study, Rezai-Zadeh's team used a mouse model of Alzheimer's
disease to test their theory. Using, luteolin and diosmin, the researchers
were able to reduce the levels of beta-amyloid in the rodents' brains.

In addition, the researchers found these two molecules were targeting a
protein called presenilin-1, which has been linked to a genetic cause of
Alzheimer's disease. These findings could lead to a new approach for
treating Alzheimer's patients, they said.

One expert is concerned this potential treatment could also affect a
patient's cognitive functioning.

“The authors of this study believe that they have identified a drug
with a reasonable safety record that could reduce both plaques and
tangles,” said Greg M. Cole, associate director of the Alzheimer's Disease
Research Center at the UCLA David Geffen School of Medicine in Los
Angeles.

However, the enzyme (GSK3) targeted by these flavonoids has many
important functions, including a role in processes required for normal
cognitive function, Cole said.

“In fact, complete inhibition of GSK3 causes neurons to degenerate.
Since cognitive function was not evaluated in this study, researchers
still need to learn how much inhibiting GSK3 will be beneficial and side
effect-free. That said, this may be a promising new direction,” Cole
said.

Another expert cautions that promising findings in mice often do not
translate into effective treatments in humans.

“While this paper also shows some promising results in
amyloid-depositing mice, we know from our recent experience with Alzhemed
[a drug to treat Alzheimer's] and statins that the path from 'mouse cures'
to 'human cures' may be a tough path indeed,” said Dr. Sam Gandy, chairman
of the National Medical and Scientific Advisory Council at the Alzheimer's
Association and associate director of the Mount Sinai Alzheimer's Disease
Research Center at Mount Sinai School of Medicine in New York City.

“Both Alzhemed and statins were effective in mice, yet failed in the
clinic, so the flavonoid data join NSAIDs, vaccines, PBT2, IVIg, secretase
modulators, among others, in the queue of interventions that look
promising in mice but remain to be thoroughly assessed in humans,” Gandy
said.

More information

For more on Alzheimer's disease, visit the Alzheimer's
Association.