Israeli Researchers Show Green Tea Has Rejuvenating Effect on Damaged Brain Cells by David Brinn
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
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
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."
Back to Health