title: Calorie restriction and not glucagon-like peptide-1 explains the acute improvement in glucose control after gastric bypass in Type 2 diabetes.
abstract: To compare directly the impact of glucagon-like peptide-1 secretion on glucose metabolism in individuals with Type 2 diabetes listed for Roux-en-Y gastric bypass surgery, randomized to be studied before and 7 days after undergoing Roux-en-Y gastric bypass or after following a very-low-calorie diet.
  
  
  
  A semi-solid meal test was used to investigate glucose, insulin and glucagon-like peptide-1 response. Insulin secretion in response to intravenous glucose and arginine stimulus was measured. Hepatic and pancreatic fat content was quantified using magnetic resonance imaging.
  
  
  
  The decrease in fat mass was almost identical in the Roux-en-Y gastric bypass and the very-low-calorie diet groups (3.0±0.3 and 3.0±0.7kg). The early rise in plasma glucose level and in acute insulin secretion were greater after Roux-en-Y gastric bypass than after a very-low-calorie diet; however, the early rise in glucagon-like peptide-1 was disproportionately greater (sevenfold) after Roux-en-Y gastric bypass than after a very-low-calorie diet. This did not translate into a greater improvement in fasting glucose level or area under the curve for glucose. The reduction in liver fat was greater after Roux-en-Y gastric bypass (29.8±3.7 vs 18.6±4.0%) and the relationships between weight loss and reduction in liver fat differed between the Roux-en-Y gastric bypass group and the very-low-calorie diet group.
  
  
  
  This study shows that gastroenterostomy increases the rate of nutrient absorption, bringing about a commensurately rapid rise in insulin level; however, there was no association with the large post-meal rise in glucagon-like peptide-1, and post-meal glucose homeostasis was similar in the Roux-en-Y gastric bypass and very-low-calorie diet groups. (Clinical trials registry number: ISRCTN11969319.).
authors: Magnetic Resonance Centre, Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne, UK.
authors: S
authors: S
authors: Steven
authors: Magnetic Resonance Centre, Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne, UK.
authors: K G
authors: KG
authors: Hollingsworth
authors: Department of Surgery, Sunderland Royal Hospital, Sunderland, UK.
authors: P K
authors: PK
authors: Small
authors: Department of Surgery, North Tyneside General Hospital, North Shields, UK.
authors: S A
authors: SA
authors: Woodcock
authors: Centre for Obesity Research, University College London, London, UK.
authors: A
authors: A
authors: Pucci
authors: Computer Science Department, Faculty of Science, Lagos State University, Lagos, Nigeria.
authors: B
authors: B
authors: Aribasala
authors: Magnetic Resonance Centre, Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne, UK.
authors: A
authors: A
authors: Al-Mrabeh
authors: Centre for Obesity Research, University College London, London, UK.
authors: R L
authors: RL
authors: Batterham
authors: Magnetic Resonance Centre, Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne, UK.
authors: R
authors: R
authors: Taylor
mesh_terms: D000273:Adipose Tissue / Q000378:metabolism; D000328:Adult; D000368:Aged; D000596:Amino Acids; D001120:Arginine / Q000008:administration & dosage / Q000494:pharmacology; D001786:Blood Glucose / Q000096:biosynthesis / Q000378:metabolism; D001823:Body Composition; D031204:Caloric Restriction; D002857:Chromium; D003924:Diabetes Mellitus, Type 2 / Q000378:metabolism / Q000628:therapy*; D005260:Female; D015390:Gastric Bypass; D052216:Glucagon-Like Peptide 1 / Q000378:metabolism*; D005947:Glucose / Q000008:administration & dosage / Q000494:pharmacology; D006442:Glycated Hemoglobin / Q000378:metabolism; D006801:Humans; D007328:Insulin / Q000378:metabolism; D007333:Insulin Resistance / Q000502:physiology; D000078790:Insulin Secretion; D008049:Lipase / Q000235:genetics; D008099:Liver / Q000737:chemistry; D008297:Male; D008565:Membrane Proteins / Q000235:genetics; D008875:Middle Aged; D009539:Nicotinic Acids; D010179:Pancreas / Q000737:chemistry; D014280:Triglycerides / Q000378:metabolism; D000217:Acyltransferases; D054512:Phospholipases A2, Calcium-Independent
chemical_list: D000596:Amino Acids; D001120:Arginine; D001786:Blood Glucose; D002857:Chromium; D052216:Glucagon-Like Peptide 1; D005947:Glucose; D006442:Glycated Hemoglobin; D007328:Insulin; D008049:Lipase; D008565:Membrane Proteins; D009539:Nicotinic Acids; D014280:Triglycerides; C015240:glucose tolerance factor; C533682:PNPLA3 protein, human; D000217:Acyltransferases; D054512:Phospholipases A2, Calcium-Independent