Islet Inflammation Impairs the Pancreatic beta-Cell in Type 2 Diabetes

Division of Endocrinology, Diabetes, and Nutrition, and Center for Integrated Human Physiology, University Hospital of Zürich, Zürich, Switzerland.
Physiology (Impact Factor: 5.65). 12/2009; 24(6):325-31. DOI: 10.1152/physiol.00032.2009
Source: PubMed

ABSTRACT Onset of Type 2 diabetes occurs when the pancreatic beta-cell fails to adapt to the increased insulin demand caused by insulin resistance. Morphological and therapeutic intervention studies have uncovered an inflammatory process in islets of patients with Type 2 diabetes characterized by the presence of cytokines, immune cells, beta-cell apoptosis, amyloid deposits, and fibrosis. This insulitis is due to a pathological activation of the innate immune system by metabolic stress and governed by IL-1 signaling. We propose that this insulitis contributes to the decrease in beta-cell mass and the impaired insulin secretion observed in patients with Type 2 diabetes.

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