Green Tea Component Battles Sepsis

An antioxidant catechin, which is a major constituent of green tea, could help fight severe sepsis, according to a new study.

Researchers at The Feinstein Institute for Medical Research (Manhasset, NY, USA) examined the therapeutic powers of dozens of Chinese herbal compounds in an attempt to find a way to block high mobility group box 1 (HMGB1), a chromatin protein expressed in the late stages of lethal sepsis, theorizing that this would prevent the lethal sepsis process from moving forward. Among the substances examined was a substance found in green tea called Epigallocatechin gallate (EGCG), which was given to mice in the throes of severe sepsis caused by cecal ligation and puncture. The dose administered was equivalent to 10 cups of tea in a human being.

The researchers found that intraperitoneal administration of EGCG protected the mice against lethal endotoxemia, and rescued mice from lethal sepsis even when the first dose was given 24 hours after puncture. Survival rate jumped from 53% in those who didn't receive the green tea substance to 82% in those who did. The researchers found that the compound prevented HMGB1 from being released by immune cells, and suppressed HMGB1-mediated inflammatory responses by preventing clustering of exogenous HMGB1 on macrophage cell surface. The study was published online in the November 7, 2007, issue of the Public Library of Science journal ONE (PLoS-ONE).

"Clinically, even if we could save five percent of patients, that would be huge,” said lead author Dr. Haichao Wang, Ph.D. "In this study, we saved 25% more animals with the green tea.”

Catechins are polyphenolic antioxidant plant metabolites present in numerous plant species. The largest source in the human diet is from various teas derived from the tea-plant Camellia Sinensis. Green tea catechins have also been shown to possess antibiotic properties, due to their role in disrupting a specific stage of the bacterial DNA replication process.


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The Feinstein Institute for Medical Research