Danforth Center Researcher Finds Potential Therapy for a Rare Insulin Disorder in Green Tea; Collaboration With The Children's Hospital Of Philadelphia Merges Plant Science And Human Health.

ST. LOUIS -- A research team led by the Donald Danforth Plant Science Center has discovered that green tea could provide a potential new therapy for a rare and often fatal insulin disorder.

As published today in the Journal of Biological Chemistry, Dr. Thomas Smith, Principal Investigator at the Donald Danforth Plant Science Center, Dr. Charles Stanley of The Children's Hospital of Philadelphia and Dr. Franz Matschinsky of the Department of Biochemistry and Diabetes Center, University of Pennsylvania School of Medicine, has determined that epigallocatechin gallate (EGCG) and epicatechin gallate (ECG), two polyphenols found in green tea, can play a significant role in modulating human insulin production. The team determined that the polyphenols are responsible for regulating the production of the enzyme glutamate dehydrogenase (GDH).

"The release of insulin from the pancreas is similar to an automobile manufacturing plant in which specific parts and processes are needed at the right time and in the proper amounts to assemble a complete car. In people producing too little or too much insulin, the pancreas does not contain all the right parts to produce the right amounts of insulin. We've found that green tea polyphenols impact sections of this insulin-production line," Dr. Smith explained.

"Previous research conducted by Dr. Stanley on hyperinsulin/hyperammonemia (HI/HA) syndrome has shown that GDH plays a regulatory role in the process of insulin secretion by pancreatic beta-cells," said Dr. Smith. "Children born with this disease have lost the ability to turn off this enzyme. In most children, this often leads to low blood sugar, coma, and eventually death."

"Our new research supports the hypothesis that GDH plays a role in insulin regulation and demonstrates that these safe and non-toxic compounds found in green tea can help to turn off this uncontrollable enzyme and may eventually lead to a new family of therapeutics," Dr. Smith explained.

"Dr. Smith's research is an example of how research can lead in unanticipated directions; in this case, Dr. Smith identified a chemical in plant leaves that can impact a human condition. While the results were not anticipated, they are logical and, now, can be explained by experimental results. Such discoveries are the tip of the iceberg that awaits as plant biologists work together with scientists in other disciplines to identify areas of common interest and potential applications," explained Danforth Center President, Dr. Roger N. Beachy. "The first phase of plant science focused on disease resistance to increase yields; the next phase of research is focused on developing new plant varieties that will contain enhanced nutritional and other compounds that will improve human health and address chronic diseases such as diabetes."

The research partnership that led to these findings was created by coincidence in 1998 when Dr. Smith published the first structure of mammalian GDH and Dr. Stanley announced that GDH plays a regulatory role in insulin secretion. When the researchers read each other's papers, they began their collaboration.

About The Donald Danforth Plant Science Center

Founded in 1998, the Donald Danforth Plant Science Center is a not-for-profit research institute with a global vision to improve the human condition. Research at the Danforth Center will enhance the nutritional content of plants to improve human health, increase agricultural production to create a sustainable food supply, and build scientific capacity to generate economic growth in the St. Louis region and throughout Missouri.

Please visit www.danforthcenter.org for additional information.