TY - JOUR

T1 - β Cell function after Roux-en-Y gastric bypass surgery or reduced energy intake alone in people with obesity

AU - Mittendorfer, Bettina

AU - Patterson, Bruce W

AU - Magkos, Faidon

AU - Yoshino, Mihoko

AU - Bradley, David P

AU - Eagon, J Christopher

AU - Klein, Samuel

N1 - Funding: This study was supported by NIH grants R01 DK037948, R01 DK101578, P30 DK056341 (Washington University Nutrition and Obesity Research Center), P30 DK020579 (Washington University Diabetes Research Center), and UL1 TR002345 (Washington University Institute of Clinical and Translational Sciences), and grants from the American Diabetes Association (1-18-ICTS-119), the Longer Life Foundation (2019-011).

PY - 2023

Y1 - 2023

N2 - Background/Aims: The effects of diet-induced weight loss (WL) and WL after Roux-en-Y gastric bypass (RYGB) surgery on β cell function (BCF) are unclear because of conflicting results from different studies, presumably because of differences in the methods used to measure BCF, the amount of WL between treatment groups, and baseline BCF. We evaluated the effect of WL after RYGB surgery or reduced energy intake alone on BCFβ-cell function in people with obesity with and without type 2 diabetes.Methods: BCF (insulin secretion in relationship to plasma glucose) was assessed before and after glucose or mixed-meal ingestion before and after (a)  progressive amounts (6%, 11%, 16%) of WL induced by a low-calorie diet (LCD) in people with obesity without diabetes, (b) ~20% WL after RYGB surgery or laparoscopic adjustable gastric banding (LAGB) in people with obesity without diabetes, and (c) ~20% WL after RYGB surgery or LCD alone in people with obesity and diabetes.Results: Diet-induced progressive WL in people without diabetes progressively decreased BCF. Marked WL after LAGB or RYGB in people without diabetes did not alter BCF. Marked WL after LCD or RYGB in people with diabetes markedly increased BCF, without a difference between the two groups.Conclusion: Marked WL increases BCF in people with obesity and diabetes but not in people with obesity without diabetes. The effect of RYGB-induced WL on BCF is not different from the effect of matched WL after LAGB or LCD alone.Clinical trial registration numbers: NCT00981500, NCT02207777, NCT01299519

AB - Background/Aims: The effects of diet-induced weight loss (WL) and WL after Roux-en-Y gastric bypass (RYGB) surgery on β cell function (BCF) are unclear because of conflicting results from different studies, presumably because of differences in the methods used to measure BCF, the amount of WL between treatment groups, and baseline BCF. We evaluated the effect of WL after RYGB surgery or reduced energy intake alone on BCFβ-cell function in people with obesity with and without type 2 diabetes.Methods: BCF (insulin secretion in relationship to plasma glucose) was assessed before and after glucose or mixed-meal ingestion before and after (a)  progressive amounts (6%, 11%, 16%) of WL induced by a low-calorie diet (LCD) in people with obesity without diabetes, (b) ~20% WL after RYGB surgery or laparoscopic adjustable gastric banding (LAGB) in people with obesity without diabetes, and (c) ~20% WL after RYGB surgery or LCD alone in people with obesity and diabetes.Results: Diet-induced progressive WL in people without diabetes progressively decreased BCF. Marked WL after LAGB or RYGB in people without diabetes did not alter BCF. Marked WL after LCD or RYGB in people with diabetes markedly increased BCF, without a difference between the two groups.Conclusion: Marked WL increases BCF in people with obesity and diabetes but not in people with obesity without diabetes. The effect of RYGB-induced WL on BCF is not different from the effect of matched WL after LAGB or LCD alone.Clinical trial registration numbers: NCT00981500, NCT02207777, NCT01299519

U2 - 10.1172/jci.insight.170307

DO - 10.1172/jci.insight.170307

M3 - Journal article

C2 - 37166995

VL - 8

JO - JCI Insight

JF - JCI Insight

SN - 2379-3708

IS - 12

M1 - e170307

ER -