Diabetes mellitus is a global health problem and its frequency is dramatically rising all over the world. It is a metabolic disease that is characterized by abnormally high levels of glucose in the blood. The main hormone controlling glucose metabolism is insulin. Insulin is released by pancreatic -cells in response to circulating glucose concentrations. Therefore, regulation of blood glucose is dependent on an adequate number of pancreatic -cells that respond appropriately to blood glucose concentrations. In diabetes this regulation fails. Autopsy studies report deficits in -cell mass...