Cold mice might be skewing weight loss drug studies

Tuesday, August 30, 2011

Daniel_SmithAnimals or people who are cold burn more calories in an effort to keep warm and a University of Alabama at Birmingham researcher thinks temperature might be a factor in evaluating the success of weight loss drugs.  Daniel Smith, Ph.D., an instructor in the Department of Nutrition Sciences, has been selected as one of two recipients of the 2011 Early-Career Research Grants for up to $25,000 from The Obesity Society. His proposal is to measure the impact of room temperature on obesity-related drug effects in mice.

“More than 90 percent of weight loss drugs that show promising results in lab tests fail to reach approval for treatment in humans,” said Smith. “There appears to be a translation gap from the bench to the market. I think the temperature used in animal research facilities may be part of the reason.”

Smith noted that most animals are tested in rooms where the temperature is near 22 degrees Celsius (72F), which is comfortable for most adult humans. However, that temperature is cold for mice which have to eat more to get their metabolic rate up to meet the constant cold stress.

“If you raise the temperature to 30 degrees Celsius, that puts the mice in their thermoneutral zone or a comfortable temperature for them, mimicking more closely what humans experience in modern daily life,” said Smith.

Smith will test a handful of weight loss drugs in a group of mice housed at 22 degrees Celsius and another group at 30 degrees Celsius.  Measurements of food intake, body weight and body composition (like body fat) will be made to determine drug-related weight loss effects between the two different temperatures. He said this study could be an important turning point for obesity researchers using animal models.

“This could change the models of pre-clinical drug testing,” said Smith.

Smith will be acknowledged at The Obesity Society’s Twenty-ninth Annual Scientific Meeting in Orlando, Fla. in October.  The organization received 90 applicants of which Smith was among the top 12. Only two received the grant which is a one-year pilot study beginning September 12.