Activating thyroid hormone receptor may rev up metabolism

Kevin Phillips

Kevin Phillips, a researcher at Houston Methodist Research Institute, has already done research on the thyroid hormone receptor agonist GC-1 as it relates to reducing cholesterol. Now he says that higher doses offer a path to developing a new drug for weight loss.

By activating these receptors, he says in a new study, GC-1 can help rev up metabolism, turning food into energy. And it has an additional positive role to play in thermogenesis, turning calories and fat into heat.

Studying this approach in hundreds of mice which were both genetically designed to be fat as well as pushed to obesity through a bad diet, the researchers were able to use GC-1 to cut fat mass in half in two weeks. And as often happens with weight loss, there was also an improvement in insulin sensitivity--indicating that there could be a role here in diabetes.

"GC-1 dramatically increases the metabolic rate, essentially converting white fat, which stores excess calories and is associated with obesity and metabolic disease, into a fat like calorie-burning brown fat," said Phillips, adding that GC-1 has been in clinical studies under the name sobetirome. "Our data demonstrate that GC-1 is a novel fat-browning agent that may have use in the treatment of obesity and metabolic disease."

The NIH in part paid for this work, which could prove a crude indicator of its potential in humans. Weight-loss drugs have proven to be a tough challenge to develop, as demonstrated by such companies as Orexigen ($OREX), Arena ($ARNA) and others, which spent years doing clinical studies to convince regulators that their drugs were both safe and effective. And they have been even more difficult to market.

- here's the release