1756-P: β-Cell Glucose Sensitivity and Intrapancreatic Adipose Tissue as Predictors of Diabetes Onset

Several evidences suggest that the functional β cell defects anticipate the onset of hyperglycemia and the reduction of mass. To assess whether the β-cell deterioration corresponds to a loss of β-cell mass, we performed glucose oral tolerance test (OGTT) and hyperglycemic clamp (HC) followed by arginine stimulation, in 16 nondiabetic patients who underwent pancreatoduodenectomy (PD), pre and post-surgery. Based on the post-operative OGTT, the subjects were divided into 3 glucose tolerance groups: normal (NGT, n = 5), altered (IGT, n = 4) or diabetes (DM, n = 7) (8F/8M, 51 ± 15 years). To evaluate β cell function, βcell glucose sensitivity (GS) was calculated during HC, as a ratio between insulin secretion and glucose increase. On surgical pancreas samples, the% of intraparenchymal white adipose tissue (WATi score) was measured. Before surgery, insulin secretion after arginine (AIS) was similar between groups, while GS was lower in IGT and DM compared to NGT subjects (62.9 ± 23.1 and 45.5 ± 11.2 vs. 90.6 ± 18.7 pmol • min-1 • m-2, respectively). After 50% PD, the GS decreased in all patients (p