Green Tea

"Tea is a miraculous medicine for the maintenance of health. Tea has an extraordinary power to prolong life" by the monk Eisai of Japan 1211, considered the "Father of Tea"

For tea products see Teavana and

The tea plant Camellia sinensis is native to South China and was brought to Japan by the Zen priest Eisai.

Green tea is obtained by steaming freshly harvested tea leaves, thus causing inactivation of enzymes that initiate the fermentation process.

Although green tea consists of over 2000 components, the flavinol polyphenic compounds are the most abundant, accounting for over 30% of the dry weight of green tea leaves. These compounds are commonly known as catechins and include the following:

EGCG: EGCG is one of the major polyphenolic components of tea, especially green tea. The assertion that EGCG is the strongest biologically active form of the catechin isomers is due to the fact that it contains both of the pyrogallol and galloyl groups.

EGC: epigallocatechin

ECG: epicatechin gallate

EC: epicatechin lacks a galloyl group.

A receptor for Green Tea Polyphenol EGCG

A 67-kDa laminin receptor (67 LR) has been identified as a receptor for EGCG.

Mechanisms of Action

EGCG and other catechins inhibit LPS induced NF-kB activation by inducing rapid degradation of IkBalpha.

Catechins inhibit p38 MAPK activation, but reportedly augments p44/p42 ERK, suggesting differential role of catechins regulating MAP and ERK activation (murine peritoneal exudate cells).

EGCG reportedly protects normal human salivary acinar cells from TNF-alpha induced cytotoxicity. This protection is associated with specific phosphorylation of p38 MAPK, and inhibitors of the p38 MAPK pathway blocked this protective effect.