The early effects of bariatric surgery on insulin secretion and action in obese subjects with type 2 diabetes (T2D) remains poorly investigated. Here we assessed the mechanisms resulting in improved glucose intolerance using the oral minimal model approach. An oral glucose tolerance test was performed before and 2 months after bariatric surgery in 16 obese T2D subjects (9 bypass, 7 gastric sleeve) and in 8 healthy control subjects. For each visit, body mass index (BMI) was measured, and the oral glucose and the insulin and C-peptide minimal models were used to estimate insulin sensitivity (SI) , glucose effectiveness (GE) , total β-cell responsiveness (Φtot) , disposition index (DI) and total hepatic insulin extraction (HE) . Bariatric surgery resulted in a significant reduction (similar between bypass and sleeve groups) in BMI by 14% (from 42±5 to 36±4 kg/m2) . Glucose tolerance increased comparably after bypass and sleeve, but remained impaired compared to the control group (Figure 1) : GE, Φtot, DI and HE were equally increased following bariatric surgery, whereas insulin action (SI) remained unaltered in the two groups. These results suggest that improved glucose tolerance in obese T2D subjects 2 months after bariatric surgery is attributable mainly to an increase in insulin secretion and glucose effectiveness rather than an improvement in insulin action.
R. Visentin: Research Support; Becton, Dickinson and Company, MannKind Corporation, Sanofi-Aventis Deutschland GmbH. K. Brodersen: None. N. Moller: None. C. Dalla Man: Research Support; Becton, Dickinson and Company, Sanofi-Aventis Deutschland GmbH. M.F. Nielsen: None.
Novo Nordisk Foundation
