Sled dogs to be subject of diabetes research

The sled dogs who run the Iditarod Trail Sled Dog Race might not only be rushing toward the finish line, but also toward possible new treatments for conditions such as type 2 diabetes and obesity.

These initial theories came out of an ongoing study led by Oklahoma State University professor Michael Davis. MSU professor Ray Geor and Shannon Pratt from North Carolina State University are working with Davis on the study.

“One of the overall goals of this work is to understand why and how dogs have such extremely good endurance capacity, in other words, the ability to run for extended duration on repeated days and what physically underlies that,” Geor said. “This specific project is actually looking at insulin sensitivity and adaptation in the skeletal muscles that relate to the insulin sensitivity and utilization of glucose in muscles.”

Insulin is a hormone produced by the pancreas that promotes the storage of nutrients consumed in food and helps keep blood glucose levels even. Insulin sensitivity basically is the measure of effectiveness of the insulin to drive the uptake of glucose in to a cell, Geor said.

In type 2 diabetes, people produce insulin, but their cells have difficulty in absorbing it, said Pat DeVoe, president of the Diabetes Action Research and Education Foundation, which helped partly fund the research.

The research takes place in Alaska, where the team has contracted a professional kennel that provides the dogs, Davis said.

The dogs are tested three times throughout their training — from when they are relatively inactive to when they are in peak physical condition, Geor said.

“I didn’t know how novel (the study) was, but one of the researchers (on the selection panel) commented that there had been the research on muscles cells and how this affects
the insulin pathways,” DeVoe said.

DeVoe said they are hoping the findings of the research will translate into new treatments for type 2 diabetes.

“We’re talking about the basic understanding of how muscle works,” Davis said. “One of the more common features of type 2 diabetes is a lack of insulin sensitivity of all the tissues in the body. Muscle is the greatest mass that is insulin sensitive and serves as an energy storage point.”

The dogs either get a muscle biopsy, where a small piece of muscle tissue is sampled, or they have their insulin checked. Each dog only gets one of these tests because they interfere with each other’s results, Davis said.

About 20 dogs are being tested, he said. The project is a subset of research that Davis has been conducting on sled dogs for about a decade.

“We’re hoping to gain an improved understanding of the molecular mechanism that regulates insulin sensitivity as it relates to different levels of training and we hope it will identify key therapies that target for improving insulin sensitivity,” Geor said.