Skin Cell Regulator 
Green tea could hold promise for skin disorders such as psoriasis and dandruff, MCG researchers say.
Researchers studied an animal model for inflammatory skin diseases. Those treated with green tea showed slower growth of skin cells and the presence of a gene that regulates the cells’ life cycles.
“Psoriasis, an autoimmune disease, causes the skin to become thicker because the growth of skin cells is out of control,” said Dr. Stephen Hsu, an oral biologist in the School of Dentistry and lead investigator on the study published in the Aug. 18 edition of Experimental Dermatology. Other autoimmune diseases with similar side effects include lupus and dandruff.
Green tea, already shown to suppress inflammation, helps by regulating the expression of Caspase-14, a protein in genes that regulates the life cycle of a skin cell. “That marker guides cells by telling them when to differentiate, die off and form a skin barrier,” Dr. Hsu said. “In psoriasis, that process is interrupted and the skin cells don’t die before more are created and the resulting lesions form.”
Animals treated with green tea also showed reduced
levels of proliferating cell nuclear antigen, a gene
expressed when skin cells multiply. In psoriasis, the gene is
over-expressed and speeds production of skin cells.
“Before treatment, the antigen, PCNA, was present in all layers of the skin,” Dr. Hsu said. “Typically, PCNA is only found in the basal layer, the innermost layer where skin cells continually divide and new cells push the older ones to the skin surface, where they eventually slough off. After being treated with green tea, the animal models showed near-normal levels of PCNA in only the basal layers.”
He hopes the research will lead to new treatments for psoriasis and dandruff with minimal side effects. Dr. Stephen Hsu.
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Dr. Stephen Hsu