Nutrition, exercise, and type 2 diabetes
Down the hall from Dr. McCargar's office you can find Dr. David Wright, whose research focuses on the effects of diet and exercise on metabolism in fat and muscle tissue. After completing graduate work in exercise physiology and metabolism, in the United States, Dr. Wright hoped to find a faculty position in Western Canada. An AHFMR Scholar award brought him to the University of Alberta in July 2006.
Type 2 diabetes and obesity are the big picture for Dr. Wright. He points out that we have known for 30 or 40 years that exercise can improve insulin sensitivity and prevent the development of type 2 diabetes. "However, the sad fact is that people aren't exercising, we're getting fatter as a country, and the incidence of type 2 diabetes is increasing."
So Dr. Wright wants to figure out just how exercise improves insulin sensitivity. He hopes to determine the beneficial effects of exercise related to insulin, and identify the mechanisms involved, in order to mimic those effects through nutrition. "People with type 2 diabetes probably can't exercise at a high enough intensity or for a long enough duration to induce some of the benefits of exercise," he explains. "So if we can find non-pharmaceutical interventions which have the same effects, it could have a very big impact on healthcare delivery."
To study these questions, Dr. Wright induces insulin resistance in rodents by feeding them high-fat diets for 6 to 8 weeks. Once he identifies the actual changes leading to insulin resistance, he tries to prevent them with exercise or with certain nutritional treatments.
Dr. Wright thinks that fat tissue may be one of the key culprits in the development of insulin resistance. He explains that years ago fat was considered nothing more than inert, unsightly tissue. Over the past 5 to 10 years, however, research has suggested that fat is an active endocrine organ, secreting many factors capable of influencing insulin action in the body. "I'm hypothesizing that one of the initial defects in the development of whole-body insulin resistance occurs in fat tissue, which then precedes changes in the whole-body glucose metabolism," he explains.
The Alberta Diabetes Institute
Like many nutrition researchers at the University of Alberta, Dr. Wright will relocate to the Health Research Innovation Facility once it is completed. This building (AHFMR contributed $20 million toward its construction) will house the Alberta Diabetes Institute, where researchers will study diabetes from a variety of angles—from basic research to clinical applications and everything in between. "It will be a very good environment for my work," says Dr. Wright.