GC-1 drug shifts bad 'white' fat into good, calorie-burning 'brown' fat in mice

Baylor's Kevin Phillips

Researchers at Baylor College of Medicine have published animal research that provides some proof that an experimental drug could one day provide a new therapeutic to effectively fight fat by pushing "bad" white fat to become "good" brown fat.

Earlier this year the lead researcher reported that GC-1 slashed cholesterol and boosted metabolism. Kevin Phillips, assistant professor of molecular and cellular biology, had speculated GC-1 works by "browning" white fat. And although they were hesitant to accept it at the time, it is now looking more promising with their new publication in the journal Cell Reports.

"We didn't believe it at first, the magnitude of the effect was just too large," says Phillips, referring to the rapid action of the GC-1 to bring about weight loss in a genetic mouse model of obesity.

They showed that the synthetic small molecule GC-1 works more specifically by activating the thyroid receptor on white fat cells. This shifts the cell to behave more like a brown fat cell known for its heat production through burning calories.

Fat has been an intensively researched area because of the great demands for anti-obesity medication in society, although a successful drug is still yet to reach the market.

It was only recently known that brown fat exists in adults and since then multiple strategies to influence the composition of fat have been proposed, including brown fat cell implants as well as "browning" fat cells by interrogating different pathways. Third Rock bought into one of those approaches, launching Ember Therapeutics in 2012, only to watch its work founder at the prospect of spending years doing preclinical work before they could make it into the clinic. Regulators have a particularly high safety bar on weight drugs as well, requring big trials. And Big Pharma has largely stayed away after being burned by earlier market failures and safety issues.

Phillips and the chemist responsible for synthesizing GC-1 believe a more potent version of the small molecule drug is on the horizon and so far the current GC-1 molecule has yet to be tested in human subjects.

- here's the release
- here's the recent Cell publication