After some follow-up experiments to figure out exactly which molecules were controlled by BAF60c, Lin and his team were confident that they had identified major players responsible for promoting white muscle formation. Now that they knew how to make more white muscle in animals, they wanted to determine whether white muscle was a deleterious or an adaptive characteristic of diabetes.
The team induced obesity in mice by feeding them the "Super Size Me" diet, Lin said. On a high-fat diet, a mouse will double its body weight in two to three months. They found that obese mice with BAF60c transgene were much better at controlling blood glucose.
"The results are a bit of a surprise to many people," Lin said. "It really points to the complexity in thinking about muscle metabolism and diabetes."
In humans, resistance training promotes the growth of white muscle and helps in lowering blood glucose. If future studies in humans determine that the BAF60c pathway is indeed the way in which cells form white muscle and in turn optimize metabolic function, the finding could lead to researching the pathway as a drug target.
"We know that this molecular pathway also works in human cells. The real challenge is to find a way to target these factors," Lin said.
Lin is a research faculty member of the Life Sciences Institute, where his laboratory is located and all his research is conducted. He is also an associate professor in the Department of Cell and Developmental Biology at the U-M Medical School.
In addition to Lin and Meng, other authors on the paper were Siming Li and Lin Wang from the U-M Life Sciences Institute; Hwi Jin Ko, Yongjin Lee, Dae Young Jung and Jason K. Kim from the Program in Molecular Medicine at the University of Massachusetts Medical School; and Mitsuharu Okutsu and Zhen Yan from the University of Virginia departments of Medicine and Pharmacology and Center for Skeletal Muscle Research at Robert M. Berne Cardiovascular Research Center. Support for the research was provided by the Michigan Diabetes Research and Training Center, Nutrition Obesity Research Center, National Institutes of Health and the American Heart Association.
Source: University of Michigan