title: CXCL5 is required for angiogenesis, but not structural adaptation after small bowel resection.
abstract: OBJECTIVE
  Intestinal adaptation is the compensatory response to massive small bowel resection (SBR) and characterized by lengthening of villi and deepening of crypts, resulting in increased mucosal surface area. Previous studies have demonstrated increased villus capillary blood vessel density after SBR, suggesting a role for angiogenesis in the development of resection-induced adaptation. Since we have previously shown enhanced expression of the proangiogenic chemokine CXCL5 after SBR, the purpose of this study was to determine the effect of disrupted CXCL5 expression on intestinal adaptation.
  
  
  METHODS
  CXCL5 knockout (KO) and C57BL/6 wild type (WT) mice were subjected to either a 50% proximal SBR or sham operation. Ileal tissue was harvested on postoperative day 7. To assess for adaptation, villus height and crypt depth were measured. Submucosal capillary density was measured by CD31 immunohistochemistry.
  
  
  RESULTS
  Both CXCL5-KO and WT mice demonstrated normal structural features of adaptation. Submucosal capillary density increased in the WT but not in the KO mice following SBR.
  
  
  CONCLUSIONS
  CXCL5 is required for increased intestinal angiogenesis during resection-induced adaptation. Since adaptive villus growth occurs despite impaired CXCL5 expression and enhanced angiogenesis, this suggests that the growth of new blood vessels is not needed for resection-induced mucosal surface area expansion following massive SBR.
authors.affiliation: Division of Pediatric Surgery, St. Louis Children's Hospital, Department of Surgery, Washington University School of Medicine, St. Louis, MO 63110, USA.
authors.forename: Kathryn J
authors.initials: KJ
authors.lastname: Rowland
authors.affiliation: Division of Pediatric Surgery, St. Louis Children's Hospital, Department of Surgery, Washington University School of Medicine, St. Louis, MO 63110, USA.
authors.forename: Jose
authors.initials: J
authors.lastname: Diaz-Miron
authors.affiliation: Division of Pediatric Surgery, St. Louis Children's Hospital, Department of Surgery, Washington University School of Medicine, St. Louis, MO 63110, USA.
authors.forename: Jun
authors.initials: J
authors.lastname: Guo
authors.affiliation: Division of Pediatric Surgery, St. Louis Children's Hospital, Department of Surgery, Washington University School of Medicine, St. Louis, MO 63110, USA.
authors.forename: Christopher R
authors.initials: CR
authors.lastname: Erwin
authors.affiliation: Division of Neonatology, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA.
authors.forename: Junjie
authors.initials: J
authors.lastname: Mei
authors.affiliation: Division of Neonatology, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA.
authors.forename: G Scott
authors.initials: GS
authors.lastname: Worthen
authors.affiliation: Division of Pediatric Surgery, St. Louis Children's Hospital, Department of Surgery, Washington University School of Medicine, St. Louis, MO 63110, USA. Electronic address: brad.warner@wustl.edu.
authors.forename: Brad W
authors.initials: BW
authors.lastname: Warner
mesh_terms: D000222:Adaptation, Physiological; D000818:Animals; D054365:Chemokine CXCL5 / Q000096:biosynthesis / Q000235:genetics*; D004195:Disease Models, Animal; D005260:Female; D005786:Gene Expression Regulation; D007150:Immunohistochemistry; D007421:Intestine, Small / Q000098:blood supply* / Q000601:surgery; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D008833:Microcirculation; D018919:Neovascularization, Physiologic / Q000235:genetics*; D012313:RNA / Q000235:genetics*; D060888:Real-Time Polymerase Chain Reaction; D012778:Short Bowel Syndrome / Q000235:genetics* / Q000473:pathology
chemical_list: D054365:Chemokine CXCL5; C094739:Cxcl5 protein, mouse; D012313:RNA
keywords: Adaptation; Angiogenesis; CXCL5; Intestine; Small bowel resection