Green tea polyphenol protects transplanted livers

A study published in the March 2005 issue of Liver Transplantation found that epigallocatechin-3-gallate (EGCG), one of the polyphenols found in green tea, protects livers from ischemia/reperfusion (I/R) injury. Ischemia reperfusion injury occurs during periods of decreased blood flow, which occur following liver transplantation.

Previous research found that the application of green tea to steatotic, or fatty livers prevented the failure of these organs following transplantation. Fatty livers are currently rejected as donor organs although the need for transplantable livers is critical. In the current study, investigators at the Medical University of South Carolina in Charleston sought to determine whether green tea might protect fatty livers from ischemic reperfusion injury.

Kenneth D. Chavin, MD, PhD and colleagues pretreated mice with EGCG administered orally for five days or by injection for two days after which ischemia was induced, followed by reperfusion. A control group of mice in whom I/R injury had been induced were pretreated with sterile water orally or by injection.

While 35 percent of the control group died, all of the mice who received EGCG survived. Mice who received EGCG were found to have less cell death and a greater amount of viable tissue than the unprotected mice. Palmitic and linoleic acid, which are fatty acids present in high amounts in fatty livers, were signficantly decreased in the mice who received EGCG, and the mice were also found to have an increase in glycogen stores compared to the controls.

The researchers determined that EGCG's antioxidant property was responsible for providing the protection observed in this study. They concluded, "the data presented here indicate that EGCG protects the steatotic liver from I/R injury by reducing hepatic fat content, increasing energy stores, serving as an antioxidant, and, possibly, stimulating the production of additional antioxidants such as GSH [glutathione]."

Source

Liver Transplantation; March 2005

Key concepts: green tea, egcg, epigallocatechin 3-gallate, liver ischemia/reperfusion I/R injury