Upregulation of intestinal glucose transporters after Roux‐en‐Y gastric bypass to prevent carbohydrate malabsorption

• Published in: Obesity (Silver Spring, Md.) Vol. 22; no. 10; pp. 2164 - 2171
• Main Authors: Nguyen, Nam Q., Debreceni, Tamara L., Bambrick, Jenna E., Chia, Bridgette, Deane, Adam M., Wittert, Gary, Rayner, Chris K., Horowitz, Michael, Young, Richard L.
• Format: Journal Article
• Language: English
• Published: United States Blackwell Publishing Ltd 01.10.2014
• Subjects: Adult; Age; Biopsy; Blood Glucose - metabolism; Carbohydrate Metabolism; Case-Control Studies; Diabetes; Female; Gastric Bypass - adverse effects; Gender; Glucose; Glucose - pharmacokinetics; Glucose Transport Proteins, Facilitative - genetics; Glucose Transport Proteins, Facilitative - metabolism; Humans; Insulin - blood; Intestinal Absorption; Intestines - metabolism; Malabsorption Syndromes - genetics; Malabsorption Syndromes - metabolism; Malabsorption Syndromes - prevention & control; Male; Middle Aged; Obesity; Obesity, Morbid - genetics; Obesity, Morbid - metabolism; Obesity, Morbid - surgery; Small intestine; Up-Regulation - genetics
• ISSN: 1930-7381; 1930-739X; 1930-739X
• DOI: 10.1002/oby.20829

Objective To determine the effect of Roux‐en‐Y gastric bypass (RYGB) on the expression of intestinal sweet taste receptors (STRs), glucose transporters (GTs), glucose absorption, and glycemia. Methods Intestinal biopsies were collected for mRNA expression of STR (T1R2) and GTs (SGLT‐1 and GLUT2) from 11 non‐diabetic RYGB, 13 non‐diabetic obese, and 11 healthy subjects, at baseline and following a 30 min small intestinal (SI) glucose infusion (30 g/150 ml water with 3 g 3‐O‐methyl‐d‐glucopyranose (3‐OMG)). Blood glucose, plasma 3‐OMG, and insulin were measured for 270 min. Results In RYGB patients, expression of both GTs was ∼2‐fold higher at baseline and after glucose infusion than those of morbidly obese or healthy subjects (P < 0.001). STR expressions were comparable amongst the groups. Peak plasma 3‐OMG in both RYGB (r = 0.69, P = 0.01) and obese (r = 0.72, P = 0.005) correlated with baseline expression of SGLT‐1, as was the case with peak blood glucose in RYGB subjects (r = 0.69, P = 0.02). Conclusions The upregulated intestinal GTs in RYGB patients are associated with increased glucose absorption when glucose is delivered at a physiological rate, suggesting a molecular adaptation to prevent carbohydrate malabsorption from rapid intestinal transit after RYGB.