title: Weight Regain After Gastric Bypass: Influence of Gut Hormones.
abstract: BACKGROUND
  The Roux-en-Y gastric bypass (RYGB) is the gold standard bariatric operation. However, a major concern in late follow-up is the substantial weight regain. Understanding the role of gastrointestinal hormone secretion in this situation is relevant.
  
  
  METHODS
  The aim of the present study was to evaluate the influence of gastrointestinal hormones comparing postprandial secretion of ghrelin, glucose-dependent insulinotropic polypeptide (GIP), glucagon-like peptide 1 (GLP-1), and leptin between patients with weight regain and those with favorable weight control. Twenty-four patients with follow-up from 27 to 59 months were divided into two groups according to sustained weight loss: group A (14 patients) had sustained weight losses, and group B (10 patients) had significant weight regain. Basal serum levels of ghrelin, GIP, GLP-1, and leptin after fasting and 30, 60, 90, and 120 min after a standard meal were measured.
  
  
  RESULTS
  There was no difference in the ghrelin secretion. There was a difference in the GIP secretion, with a higher percentage increase in 30 min in group A (330% × 192.2%; p = 0.01). There were also differences in the GLP-1 secretion, with higher increases in absolute (p = 0.03) and percentage values after 30 min in group A (124% × 46.5%; p = 0.01). There was also a difference between baseline leptin values, with higher levels in group B (p = 0.02).
  
  
  CONCLUSIONS
  The secretion of gut hormones in patients with weight regain after RYGB is different from that in patients with satisfactory weight outcome. After meal stimulation, reduced levels of GIP and GLP-1 may indicate the influence of gut hormones in the process of weight regain.
authors.affiliation: Department of Digestive Surgery, University of São Paulo School of Medicine, Av. Arnolfo Azevedo 208, São Paulo, SP, 05673-010, Brazil. santomarco@uol.com.br.
authors.forename: Marco Aurelio
authors.initials: MA
authors.lastname: Santo
authors.affiliation: Department of Digestive Surgery, University of São Paulo School of Medicine, Av. Arnolfo Azevedo 208, São Paulo, SP, 05673-010, Brazil.
authors.forename: Daniel
authors.initials: D
authors.lastname: Riccioppo
authors.affiliation: Department of Digestive Surgery, University of São Paulo School of Medicine, Av. Arnolfo Azevedo 208, São Paulo, SP, 05673-010, Brazil.
authors.forename: Denis
authors.initials: D
authors.lastname: Pajecki
authors.affiliation: Department of Digestive Surgery, University of São Paulo School of Medicine, Av. Arnolfo Azevedo 208, São Paulo, SP, 05673-010, Brazil.
authors.forename: Flavio
authors.initials: F
authors.lastname: Kawamoto
authors.affiliation: Department of Digestive Surgery, University of São Paulo School of Medicine, Av. Arnolfo Azevedo 208, São Paulo, SP, 05673-010, Brazil.
authors.forename: Roberto
authors.initials: R
authors.lastname: de Cleva
authors.affiliation: Department of Digestive Surgery, University of São Paulo School of Medicine, Av. Arnolfo Azevedo 208, São Paulo, SP, 05673-010, Brazil.|Central Laboratory of Hospital das Clínicas, São Paulo, Brazil.
authors.forename: Leila
authors.initials: L
authors.lastname: Antonangelo
authors.affiliation: Department of Digestive Surgery, University of São Paulo School of Medicine, Av. Arnolfo Azevedo 208, São Paulo, SP, 05673-010, Brazil.|Central Laboratory of Hospital das Clínicas, São Paulo, Brazil.
authors.forename: Lia
authors.initials: L
authors.lastname: Marçal
authors.affiliation: Department of Digestive Surgery, University of São Paulo School of Medicine, Av. Arnolfo Azevedo 208, São Paulo, SP, 05673-010, Brazil.
authors.forename: Ivan
authors.initials: I
authors.lastname: Cecconello
mesh_terms: D000328:Adult; D000069461:Bendamustine Hydrochloride; D015390:Gastric Bypass; D005749:Gastric Inhibitory Polypeptide / Q000097:blood*; D054439:Ghrelin / Q000097:blood*; D052216:Glucagon-Like Peptide 1 / Q000097:blood*; D006801:Humans; D020738:Leptin / Q000097:blood*; D008875:Middle Aged; D009767:Obesity, Morbid / Q000097:blood / Q000601:surgery*; D019518:Postprandial Period; D015430:Weight Gain / Q000502:physiology*
chemical_list: D054439:Ghrelin; D020738:Leptin; D005749:Gastric Inhibitory Polypeptide; D052216:Glucagon-Like Peptide 1; D000069461:Bendamustine Hydrochloride
keywords: Bariatric surgery; GLP-1; Incretins; Morbid obesity; Weight regain after bariatric surgery; Weight regain postgastric bypass