title: Detailed characterization of incretin cell distribution along the human small intestine.
abstract: BACKGROUND
  Incretin hormones, glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide 1 (GLP-1), are physiologic stimulants of insulin release that have been implicated in diabetes remission after bariatric surgery. The detailed distribution of incretin cells along the human small gut, so far unknown, is of utmost importance for the understanding of the metabolic changes observed after bariatric surgery because diabetes remission rate varies according to the type of anatomic rearrangement.
  
  
  OBJECTIVE
  To characterize the distribution of incretin producing cells along the human jejunum-ileum.
  
  
  METHODS
  Academic public institution.
  
  
  METHODS
  Small intestines (n = 30) from autopsies were sampled every 20 cm along their entire length and tissue microarrays were constructed. The percentage of immunohistochemistry-stained cell areas for GLP-1, GIP, and chromogranin A at each segment length was quantified using a computer-aided analysis tool.
  
  
  RESULTS
  The percentage of stained area for GLP-1 immunoreactive cells was found to be significantly higher from 200 cm from Treitz ligament onward compared with the first 80 cm of the small intestine, whereas GIP immunoreactive cells were predominant expressed in the first 80 cm. In contrast, chromogranin A expression was constant along the entire jejunum-ileum.
  
  
  CONCLUSIONS
  The uneven distribution of GLP-1-expressing cells, with a higher density from 200 cm of the jejunum-ileum, could contribute to explain the improvement of glycemic profile of diabetic patients observed after anatomic rearrangement of the intestinal tract, in particular when subjected to gastric bypass with longer biliopancreatic limbs.
authors.affiliation: Department of Anatomy, Unit for Multidisciplinary Research in Biomedicine (UMIB), ICBAS, University of Porto, Portugal.
authors.forename: Tiago P
authors.initials: TP
authors.lastname: Guedes
authors.affiliation: Department of Anatomy, Unit for Multidisciplinary Research in Biomedicine (UMIB), ICBAS, University of Porto, Portugal.
authors.forename: Sofia
authors.initials: S
authors.lastname: Martins
authors.affiliation: Department of Anatomy, Unit for Multidisciplinary Research in Biomedicine (UMIB), ICBAS, University of Porto, Portugal.
authors.forename: Madalena
authors.initials: M
authors.lastname: Costa
authors.affiliation: Department of Anatomy, Unit for Multidisciplinary Research in Biomedicine (UMIB), ICBAS, University of Porto, Portugal.
authors.forename: Sofia S
authors.initials: SS
authors.lastname: Pereira
authors.affiliation: Department of Anatomy, Unit for Multidisciplinary Research in Biomedicine (UMIB), ICBAS, University of Porto, Portugal.
authors.forename: Tiago
authors.initials: T
authors.lastname: Morais
authors.affiliation: Instituto Nacional de Medicina Legal e Ciências Forenses (IMNL) and Faculty of Medicine, University of Porto, Porto, Portugal.
authors.forename: Agostinho
authors.initials: A
authors.lastname: Santos
authors.affiliation: Department of General Surgery, Centro Hospitalar de Entre o Douro e Vouga, Portugal.
authors.forename: Mário
authors.initials: M
authors.lastname: Nora
authors.affiliation: Department of Anatomy, Unit for Multidisciplinary Research in Biomedicine (UMIB), ICBAS, University of Porto, Portugal. Electronic address: mpmonteiro@icbas.up.pt.
authors.forename: Mariana P
authors.initials: MP
authors.lastname: Monteiro
mesh_terms: D000328:Adult; D000368:Aged; D002102:Cadaver; D005260:Female; D006801:Humans; D007082:Ileum / Q000378:metabolism* / Q000473:pathology; D007150:Immunohistochemistry; D054795:Incretins / Q000378:metabolism*; D007413:Intestinal Mucosa / Q000378:metabolism* / Q000473:pathology; D007583:Jejunum / Q000378:metabolism* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009767:Obesity, Morbid / Q000378:metabolism*
chemical_list: D054795:Incretins
keywords: Diabetes; Human; Incretins; K cells; L cells; Small intestine