I
Ian Goddard
Guest
Medical College of Georgia http://www.mcg.edu/news/2003NewsRel/hsu.html
Green Tea Linked to Skin Cell Rejuvenation
Christine Hurley Deriso
Research into the health-promoting properties of green tea is yielding information that may lead to
new treatments for skin diseases and wounds.
Dr. Stephen Hsu, a cell biologist in the Medical College of Georgia Department of Oral Biology, has
uncovered a wealth of information about green tea in the last few years. Most importantly, he
helped determine that compounds in green tea called polyphenols help eliminate free radicals,
which can cause cancer by altering DNA. He also found that polyphenols safeguard healthy cells
while ushering cancer cells to their death.
He recently began studying the most abundant green tea polyphenol, EGCG. Using pooled human
keratinocytes (skin cells), he and his colleagues studied the normal growth of the skin cells and
compared it to the growth of the cells when exposed to EGCG.
To their astonishment, they found that EGCG reactivated dying skin cells. "Cells that migrate toward
the surface of the skin normally live about 28 days, and by day 20, they basically sit on the upper
layer of the skin getting ready to die," Dr. Hsu said. "But EGCG reactivates them. I was so
surprised."
The skin consists of three layers: the epidermis (outer layer), dermis (mid-layer) and hypodermis
(inner layer). Dr. Hsu learned that green tea polyphenols aren’t absorbed beyond the epidermis, so
any benefits are limited to that outer layer of skin. But the benefits, he stressed, seem
significant.
Cells in the epidermis, or keratinocytes, are in a constant state of renewal. The newly formed
cells, stem cells, are undifferentiated but rapidly dividing. As they push through the epidermis,
they begin differentiating. During this migration and differentiation process, the cells are very
active, expending and consuming vast amounts of energy.
Once they reach the surface of the skin, their metabolic activity slows dramatically and they
prepare to die, while forming a water-proof, sheet-like structure. As they die off about a month
into their life cycle, they are replaced by another wave of migrating cells supplied by stem cells,
starting the process all over again.
But EGCG seems to be a fountain of youth for skin cells. "When exposed to EGCG, the old cells found
in the upper layers of the epidermis appear to start dividing again," Dr. Hsu said. "They make DNA
and produce more energy. They are reactivated. There are lots of unknowns--this is the first step
into the door--but if we can energize dying skin cells, we can probably improve the skin condition."
In addition, the researchers found that EGCG accelerates the differentiation process among
new cells.
Combining these effects of EGCG on skin cells in different layers of the epidermis, Dr. Hsu noted
potential benefits for skin conditions as diverse as aphthous ulcers, psoriasis, rosascea, wrinkles
and wounds. "If skin cells surrounding wounds or infections don’t heal in time, fibroblasts in the
connective tissue may rush in to fill the void and cause scar tissue formation," he said. "If we can
spur the skin cells to differentiate and proliferate, we can potentially accelerate the
wound-healing process and prevent scarring."
This potential benefit is particularly exciting for conditions such as diabetes, which stubbornly
inhibits the wound-healing process, Dr. Hsu said.
He and his colleagues hope to identify dermatologists interested in collaborating on clinical
studies of EGCG and other polyphenols on patients.
Ds. Hsu’s research, which is excerpted on the online version of the Journal of Pharmacology and
Experimental Therapeutics, is funded by the Dental Research Foundation, the MCG School of
Dentistry and MCG Research Institute.
http://IanGoddard.net/journal.htm
"To lengthen thy life, lessen thy meals." Ben Franklin
Ongoing CR monkey study update: "In the monkeys...those on reduced feeding since the study started
are dying at a rate that is about half that of the monkeys receiving a full food ration."
Associated Press: Eating less may extend human life. August 1, 2002 :
http://www.msnbc.com/news/788746.asp?0si=-
Green Tea Linked to Skin Cell Rejuvenation
Christine Hurley Deriso
Research into the health-promoting properties of green tea is yielding information that may lead to
new treatments for skin diseases and wounds.
Dr. Stephen Hsu, a cell biologist in the Medical College of Georgia Department of Oral Biology, has
uncovered a wealth of information about green tea in the last few years. Most importantly, he
helped determine that compounds in green tea called polyphenols help eliminate free radicals,
which can cause cancer by altering DNA. He also found that polyphenols safeguard healthy cells
while ushering cancer cells to their death.
He recently began studying the most abundant green tea polyphenol, EGCG. Using pooled human
keratinocytes (skin cells), he and his colleagues studied the normal growth of the skin cells and
compared it to the growth of the cells when exposed to EGCG.
To their astonishment, they found that EGCG reactivated dying skin cells. "Cells that migrate toward
the surface of the skin normally live about 28 days, and by day 20, they basically sit on the upper
layer of the skin getting ready to die," Dr. Hsu said. "But EGCG reactivates them. I was so
surprised."
The skin consists of three layers: the epidermis (outer layer), dermis (mid-layer) and hypodermis
(inner layer). Dr. Hsu learned that green tea polyphenols aren’t absorbed beyond the epidermis, so
any benefits are limited to that outer layer of skin. But the benefits, he stressed, seem
significant.
Cells in the epidermis, or keratinocytes, are in a constant state of renewal. The newly formed
cells, stem cells, are undifferentiated but rapidly dividing. As they push through the epidermis,
they begin differentiating. During this migration and differentiation process, the cells are very
active, expending and consuming vast amounts of energy.
Once they reach the surface of the skin, their metabolic activity slows dramatically and they
prepare to die, while forming a water-proof, sheet-like structure. As they die off about a month
into their life cycle, they are replaced by another wave of migrating cells supplied by stem cells,
starting the process all over again.
But EGCG seems to be a fountain of youth for skin cells. "When exposed to EGCG, the old cells found
in the upper layers of the epidermis appear to start dividing again," Dr. Hsu said. "They make DNA
and produce more energy. They are reactivated. There are lots of unknowns--this is the first step
into the door--but if we can energize dying skin cells, we can probably improve the skin condition."
In addition, the researchers found that EGCG accelerates the differentiation process among
new cells.
Combining these effects of EGCG on skin cells in different layers of the epidermis, Dr. Hsu noted
potential benefits for skin conditions as diverse as aphthous ulcers, psoriasis, rosascea, wrinkles
and wounds. "If skin cells surrounding wounds or infections don’t heal in time, fibroblasts in the
connective tissue may rush in to fill the void and cause scar tissue formation," he said. "If we can
spur the skin cells to differentiate and proliferate, we can potentially accelerate the
wound-healing process and prevent scarring."
This potential benefit is particularly exciting for conditions such as diabetes, which stubbornly
inhibits the wound-healing process, Dr. Hsu said.
He and his colleagues hope to identify dermatologists interested in collaborating on clinical
studies of EGCG and other polyphenols on patients.
Ds. Hsu’s research, which is excerpted on the online version of the Journal of Pharmacology and
Experimental Therapeutics, is funded by the Dental Research Foundation, the MCG School of
Dentistry and MCG Research Institute.
http://IanGoddard.net/journal.htm
"To lengthen thy life, lessen thy meals." Ben Franklin
Ongoing CR monkey study update: "In the monkeys...those on reduced feeding since the study started
are dying at a rate that is about half that of the monkeys receiving a full food ration."
Associated Press: Eating less may extend human life. August 1, 2002 :
http://www.msnbc.com/news/788746.asp?0si=-