In recent years, the National Institutes of Health have announced that obesity and type 2 diabetes are among the most urgent global health problems. More than two-thirds of the adult population in the United States is overweight and at risk for type 2 diabetes. Biomedical research has made it clear that obesity and type 2 diabetes are closely related. Some physicians and scientists even describe the phenomenon as "diabesity."

Arizona resident and UBRPer, Helen Mashalidis, is studying the molecular connection between obesity and diabetes at the University of Arizona with Dr. Tsu-Shuen Tsao in the Department of Biochemistry and Molecular Biophysics. Her research is supported in part by a grant to the University of Arizona from the Howard Hughes Medical Institute (#52005889).

Type 2 diabetes is characterized by what is called "insulin resistance" or "insulin insensitivity," which means that the cells no longer respond well to insulin. The normal function of insulin is to stimulate the uptake of glucose in muscle and fat cells, where it is used for energy or stored.

" In a diabetic state, however, the body secretes insulin in an effort to reduce blood glucose levels, but cells are not sensing the presence of insulin. This leads to dangerously high concentrations of insulin and glucose in the blood," Mashalidis explains.

Dr. Tsu-Shuen Tsao's group is trying to understand why some individuals are more likely to become resistant to insulin than others. They are studying a protein found in the blood called adiponectin, which enhances insulin sensitivity in cells. Concentration of adiponectin in the blood is an indicator of a person's risk for developing type 2 diabetes. Studies show that people who have high levels of circulating adiponectin are less likely to develop type 2 diabetes. Genetic predisposition to low blood levels of adiponectin may be a reason that some people are at a greater risk for type 2 diabetes than others. However, it also has been shown that concentration of adiponectin in the blood decreases with severe weight gain. Therefore, blood concentration of adiponectin (and therefore, risk for type 2 diabetes) is dependent on both genetic factors and lifestyle decisions.

Adiponectin research provides one piece of the puzzle that is the obesity-diabetes problem. Researchers around the world are studying many other proteins that could play a role in the development of type 2 diabetes.

Mashalidis is confident that the research conducted at the University of Arizona will help us understand the complex molecular underpinnings of obesity and type 2 diabetes.

Helen Mashalidis, UBRPer in Dr. Tsu-Shuen Tsao's lab, Biochemistry and Molecular Biophysics