Clinical approaches to preserve β-cell function in diabetes

Abstract

In type 2 diabetes (DM2) there is progressive deterioration in β-cell function and mass. It was found that islet function was about 50% of normal at the time of diagnosis and reduction in β-cell mass of about 60% at necropsy (accelerated apoptosis). Among the interventions to preserve the β-cells, those to lead to shortterm improvement of β-cell secretion are weight loss, metformin, sulfonylureas, and insulin. The long-term improvement was demonstrated with short-term intensive insulin therapy of newly diagnosed DM2, the use of antiapoptotic drugs such as glitazones, and the use of glucagon-like peptide-1 receptor agonists (GLP-1 mimetics), not inactivated by the enzyme dipeptidyl peptidase 4 and/or to inhibit that enzyme (GLP-1 enhancers). The incretin hormones are released from the gastrointestinal tract in response to nutrient ingestion to enhance glucose-dependent insulin secretion from the pancreas and overall maintenance of glucose homeostasis. From the two major incretins, GLP-1 and GIP (glucose-dependent insulinotropic polypeptide), only the first one or its mimetics or enhancers can be used for treatment. The GLP-1 mimetics exenatide and liraglutide as well as the DPP 4 inhibitors (sitagliptin and vildagliptin) were approved for treatment of DM2. © Springer Science+Business Media B.V. 2010.