title: Gut hormone profiles following bariatric surgery favor an anorectic state, facilitate weight loss, and improve metabolic parameters.
abstract: OBJECTIVE
  To study the effect of bariatric surgery on the entero-hypothalamic endocrine axis of humans and rodents.
  
  
  BACKGROUND
  Bariatric surgery is the most effective obesity treatment as it achieves substantial and sustained weight loss. Glycemic control and enhanced satiation improve before substantial weight loss occurs. Gut peptides, acting both peripherally and centrally, contribute to glycemic control and regulate food intake.
  
  
  METHODS
  We examined meal-stimulated responses of insulin, ghrelin, peptide YY (PYY), glucagon-like-peptide-1 (GLP-1), and pancreatic polypeptide (PP) in humans and rodents following different bariatric surgical techniques.
  
  
  RESULTS
  Compared with lean and obese controls, patients following Roux-en-Y gastric bypass (RYGB) had increased postprandial plasma PYY and GLP-1 favoring enhanced satiety. Furthermore, RYGB patients had early and exaggerated insulin responses, potentially mediating improved glycemic control. None of these effects were observed in patients losing equivalent weight through gastric banding. Leptin, ghrelin, and PP were similar in both the surgical groups. Using a rodent model of jejuno-intestinal bypass (JIB), we showed elevated PYY and GLP-1 in JIB rats compared with sham-operated rats. Moreover, exogenous PYY reduced food intake and blockade of endogenous PYY increased food intake. Thus, higher plasma PYY following JIB may contribute to reduced food intake and contribute to weight loss.
  
  
  CONCLUSIONS
  Following RYGB and JIB, a pleiotropic endocrine response may contribute to the improved glycemic control, appetite reduction, and long-term changes in body weight.
authors.affiliation: Department of Metabolic Medicine, Hammersmith Hospital, Imperial College London, UK.
authors.forename: Carel W
authors.initials: CW
authors.lastname: le Roux
authors.forename: Simon J B
authors.initials: SJ
authors.lastname: Aylwin
authors.forename: Rachel L
authors.initials: RL
authors.lastname: Batterham
authors.forename: Cynthia M
authors.initials: CM
authors.lastname: Borg
authors.forename: Frances
authors.initials: F
authors.lastname: Coyle
authors.forename: Vyas
authors.initials: V
authors.lastname: Prasad
authors.forename: Sandra
authors.initials: S
authors.lastname: Shurey
authors.forename: Mohammad A
authors.initials: MA
authors.lastname: Ghatei
authors.forename: Ameet G
authors.initials: AG
authors.lastname: Patel
authors.forename: Stephen R
authors.initials: SR
authors.lastname: Bloom
mesh_terms: D000328:Adult; D000818:Animals; D001066:Appetite / Q000502:physiology*; D050110:Bariatric Surgery; D003430:Cross-Sectional Studies; D005260:Female; D005768:Gastrointestinal Hormones / Q000378:metabolism*; D054439:Ghrelin; D052216:Glucagon-Like Peptide 1; D006801:Humans; D007328:Insulin / Q000378:metabolism; D008297:Male; D023421:Models, Animal; D009765:Obesity / Q000378:metabolism / Q000601:surgery*; D010191:Pancreatic Polypeptide / Q000378:metabolism; D036361:Peptide Hormones / Q000378:metabolism; D019894:Peptide YY / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D015431:Weight Loss / Q000502:physiology*
chemical_list: D005768:Gastrointestinal Hormones; D054439:Ghrelin; D007328:Insulin; D036361:Peptide Hormones; D019894:Peptide YY; D010191:Pancreatic Polypeptide; D052216:Glucagon-Like Peptide 1