The role of ABC transporters on cellular cholesterol homeostasis and beta-cell function

Type 2 diabetes affects more than two million Canadians and causes a range of significant health issues, including coronary heart disease, the leading cause of death in Canada. Type 2 diabetes results from a relative insufficiency of beta-cells in the pancreas to produce enough insulin to meet the increasing metabolic demands caused by obesity and aging. Cholesterol levels among type 2 diabetes patients is also known to commonly be altered, with elevated levels of LDL (“bad cholesterol”) and low levels of HDL (“good cholesterol”). However, the mechanistic connections between cholesterol metabolism and diabetes are poorly understood. Researchers recently discovered that the cholesterol transporter ABCA1, which is crucial for regulating cholesterol levels inside cells, is also essential for the normal release of insulin in beta-cells. Mice that lack Abca1 in their beta-cells have impaired glucose tolerance due to impaired beta-cell function. Dr. Janine Kruit is working to determine the specific role of ABC transporters in beta-cell function, glucose metabolism and type 2 diabetes. Her research will focus on the cholesterol transporters ABCA1 and ABCG1. Her studies could suggest a novel mechanism for how type 2 diabetes develops, and lead to new ways to prevent and treat this disease.