The mechanisms of type-2 diabetes remission after bariatric surgery is still not fully elucidated. In the present study we tried to simulate the Roux-en-Y gastric-bypass with a canonical or longer biliary limb, by infusing a liquid-formula-diet into different intestinal sections. Nutrients (Nutrison Energy) were infused into mid or proximal jejunum, and duodenum during three successive days in 10 diabetic and 10 normal glucose-tolerant subjects. Plasma glucose, insulin, C-peptide, glucagon, incretins, and non-esterified fatty-acids (NEFA) were measured before and up to 360 min following. Glucose rate-of-appearance (Ra) and insulin sensitivity (SI), secretion rate (ISR) and clearance were assessed by mathematical models. SI increased when nutrients were delivered in mid jejunum versus duodenum (SI×104 min-1pM-1: 1.11±0.44 vs. 0.62±0.22, P<0.015, in controls and 0.79±0.34 vs. 0.40±0.20, P<0.05, in diabetic subjects), while glucose Ra was not affected. In controls, insulin sensitivity of NEFA production was doubled in mid jejunum vs. duodenum (2.80±1.36 vs. 1.13±0.78×106, P<0.005) and insulin-clearance increased in mid jejunum vs. duodenum (2.05±1.05 vs. 1.09±0.38 L×min-1, P<0.03). Bypass of duodenum and proximal jejunum by nutrients enhances insulin sensitivity, inhibits lipolysis, and increases insulin clearance. These results may further our knowledge of the effects of bariatric surgery on both insulin resistance and diabetes.
- Bariatric Surgery
- intestinal glucose infusion
- Insulin Sensitivity
- Copyright © 2012, American Journal of Physiology - Endocrinology and Metabolism