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Israeli researchers show that green tea has rejuvenating effect on damaged
brain cells
By David Brinn   October 14, 2007

Dr. Silvia Mandel: In the past, it was thought that once brain cells were
damaged, there was no way to repair them. The major question is whether
these promising results are reproducible in humans.

 The old British adage - 'have a cuppa tea' - has gained some powerful
backing as a cure for life's ailments, thanks to the results of an Israeli
study.

Researchers at the Technion Institute of Science in Haifa have shown that
feeding green tea extract to mice with Parkinson's and Alzheimer's disease
protects brain cells from dying, and helps 'rescue' already damaged neurons
in the brain.

Numerous studies around the world have suggested that drinking tea may help
support the brain as people get older. Tea consumption is inversely
correlated with the incidence of dementia, Alzheimer's disease and
Parkinson's disease, which may help to explain why there are significantly
lower incidence rates of age-related neurological disorders among Asians
than in Europeans or Americans.

But, according to Dr. Silvia Mandel of the Technion's Eve Topf Center for
Neurodegenerative Diseases, the study she led was one of the first to show
how the main antioxidant polyphenol of green tea extract, EGCG, actually
works when it gets access into the brain. Mandel presented her findings last
month in Washington DC to a rapt audience of colleagues at the Fourth
International Scientific Symposium on Tea and Human Health.

"It was received really well, and I was told there was extreme interest in
it," Mandel told ISRAEL21c. "It was novel in the sense that most studies
presented dealt with how the consumption of tea impacts several parameters
in patients affected with different maladies like cancer, diabetes and
cardio-vascular diseases. Our study was the only one that went inside the
mechanism of action of EGCG at the molecular level - what it does once it
enters the neurons."

In a preliminary study, Mandel's group provided an amount of purified EGCG
equal to about two to four cups of green tea per day to mice with induced
Parkinson's disease. They found that the EGCG prevented brain cells from
dying, and showed improvements in reducing compounds that lead to lesions in
the brains.

"More recently, a PhD student of mine - Lydia Reznichenko - conducted a
"neurorescue" study that closely resembles what happens in humans - first
the disease is diagnosed and then the doctors prescribe medication," said
Mandel. "We induced Parkinson's in mice and waited until the damage was
evident. Then we began to administer the EGCG to the animals. The results
showed that the EGCG not only prevented further deterioration, but it helped
to regenerate the already damaged neurons in the brain. This phenomenon is
called neurorescue or neurorestoration, and we're the first to show that
green tea is effective in doing this. In the past, it was thought that once
brain cells were damaged, there was no way to repair them. The major
question is whether these promising results are reproducible in humans."

"Researchers have been actively searching for better ways to support brain
cell repair for many years," said tea and health expert Dr. Carol Greenwood
who attended the DC conference. "This finding that tea, a natural product
consumed by millions of people every day, can help repair them is especially
exciting."

In her native Uruguay, Mandel majored in medicine in her high school
studies, and upon moving to Israel in 1979, attended Ben-Gurion University,
gaining a degree in Biochemistry. She received her masters and PhD in
Pharmacology from the Technion before joining the center.

"When I starting working there 10 years ago, I was told by my boss Prof.
Moussa Youdim, that the most acknowledged hypothesis regarding
neurodegenerative diseases such as Alzheimer's and Parkinson's, is an
excessive accumulation of highly reactive molecules known as oxygen free
radicals, and iron. In the brain, the radicals and iron can hit genetic
material and critical proteins - a "corrosive" oxidative effect. Therefore,
one would expect that molecules capable of neutralizing free radicals and
trapping excess of iron could be considered potential candidates for
treating Parkinson's disease," said Mandel.

"At that time I stumbled upon a research paper dealing with a green tea
extract which showed that it prevents damage to red blood cells. By a closer
examination of the components in green tea, I discovered that the most
active ingredient of the extract, EGCG, is a potent antioxidant and iron
complexing agent. I looked up some more articles, and decided that maybe I
could study this compound - in any event, it is natural so it can't do any
harm, and it would be nice to tell people that they can drink something
pleasant like tea and get beneficial effects from it," she added.

The years of research into tea are beginning to pay off for Mandel. Based on
her initial findings in 2001 about the connection of green tea to cell
protection, tests are underway now in China, under the auspices of the
Michael J. Fox Foundation, on early Parkinson's patients to check whether
green tea extract is slowing down the progression of the disease.

And don't think that Mandel doesn't take her own advice.

"I try to drink at least two cups of green tea a day. And I like regular
dark tea too, so I drink another two cups of that."

Rayilyn Brown
Board Member AZNPF
Arizona Chapter National Parkinson's Foundation
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