1. Mechanisms of type 2 diabetes resolution after Roux-en-Y gastric bypass
- Author
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Dariush Elahi, Richard P. Shannon, Franca S. Angeli, Panagis Galiatsatos, Amin Vakilipour, Atoosa Rabiee, Josephine M. Egan, Olga D. Carlson, Rocio Salas-Carrillo, and Dana K. Andersen
- Subjects
Blood Glucose ,Male ,medicine.medical_specialty ,medicine.medical_treatment ,Gastric Bypass ,Enzyme-Linked Immunosorbent Assay ,Type 2 diabetes ,Article ,Body Mass Index ,Absorptiometry, Photon ,Glucagon-Like Peptide 1 ,Internal medicine ,Weight Loss ,medicine ,Hyperinsulinemia ,Insulin ,Humans ,Meal ,C-Peptide ,business.industry ,Type 2 Diabetes Mellitus ,Middle Aged ,Glucagon ,medicine.disease ,Roux-en-Y anastomosis ,Obesity, Morbid ,Surgery ,Endocrinology ,Diabetes Mellitus, Type 2 ,Body Composition ,Glucose Clamp Technique ,Female ,business ,Body mass index ,Biomarkers ,Hormone - Abstract
BACKGROUND: Bariatric surgery is the most effective treatment for the reduction of weight and resolution of type 2 diabetes mellitus (T2 DM). The objective of this study was to longitudinally assess hormonal and tissue responses after RYGB. METHODS: Eight patients (5 with T2 DM) were studied before and after RYGB. A standardized test meal (STM) was administered before and at 1, 3, 6, 9, 12, and 15 months. Separately, a 2-hour hyperinsulinemic-euglycemic clamp (E-clamp) and a 2-hour hyperglycemic clamp (H-clamp) were performed before and at 1, 3, 6, and 12 months. Glucagon-like peptide-1 (GLP-1) was infused during the last hour of the H-clamp. Body composition was assessed with DXA methodology. RESULTS: Enrollment body mass index was 49 ± 3 kg/m(2) (X ± SE). STM glucose and insulin responses were normalized by 3 and 6 months. GLP-1 level increased dramatically at 1, 3, and 6 months, normalizing by 12 and 15 months. Insulin sensitivity (M of E-clamp) increased progressively at 3–12 months as fat mass decreased. The insulin response to glucose alone fell progressively over 12 months but the glucose clearance/metabolism (M of H-clamp) did not change significantly until 12 months. In response to GLP-1 infusion, insulin levels fell progressively throughout the 12 months. CONCLUSION: The early hypersecretion of GLP-1 leads to hyperinsulinemia and early normalization of glucose levels. The GLP-1 response normalizes within 1 year after surgery. Enhanced peripheral tissue sensitivity to insulin starts at 3 months and is associated with fat mass loss. β-cell sensitivity improves at 12 months and after the loss of ≈ 33% of excess weight. There is a tightly controlled feedback loop between peripheral tissue sensitivity and β-cell and L-cell (GLP-1) responses. (Surg Obes Relat Dis 2014;10: 1028–1040.)
- Published
- 2014