By Jim and Lynda Guidry
 

UTMB researcher Dr. Xiaodong Cheng is working to identify and block a protein that interferes with an appetite-suppressing hormone called leptin.

“My lab has been working on this molecule that was actually identified at the end of the last century,” Dr. Cheng said.  “But, in my field it’s still pretty new.” 

Leptin was discovered in 1994.  Since then scientists have been studying the mechanisms that control the molecule.

“When I established my lab here we decided to look at how this new protein functioned,” Dr. Cheng said.  “Of course, in the beginning we don’t know much about this protein, so we’ve been doing lots of basic lab work just to try to figure out how the protein functions.”
 
He said the research evolved into clinical applications which may lead to development of a drug to prevent obesity.  He recalled the advice of the department chair on his first interview.

“He said make sure you mention ‘drug discoveries’,” Dr. Cheng said.  “That is a word that kind of stuck with me.  I didn’t even know what drug discovery was at that time.”

Dr. Cheng said that he collaborated with scientists from the University of California, San Diego, to explore the role of a protein called Epac1 in blocking leptin’s activity in the brain and eventually developed an “Epac inhibitor” to treat brain-slice cultures taken from normal laboratory mice.
 
He said the goal is to develop a drug that will keep the inhibitors from interfering with natural leptin in the human body.
 
“The problem with obese people is they have this high level of leptin in their circulation, but they are not really functioning,” he said.  “It is what we call leptin resistance.  It is almost like a thermostat that is dysfunctional.”

This story was originally published in Guidry News Service.