title: Fibrotic and Vascular Remodelling of Colonic Wall in Patients with Active Ulcerative Colitis.
abstract: OBJECTIVE
  Intestinal fibrosis is a complication of inflammatory bowel disease [IBD]. Although fibrostenosis is a rare event in ulcerative colitis [UC], there is evidence that a fibrotic rearrangement of the colon occurs in the later stages. This is a retrospective study aimed at examining the histopathological features of the colonic wall in both short-lasting [SL] and long-lasting [LL] UC.
  
  
  METHODS
  Surgical samples of left colon from non-stenotic SL [≤ 3 years, n = 9] and LL [≥ 10 years, n = 10] UC patients with active disease were compared with control colonic tissues from cancer patients without UC [n = 12] to assess: collagen and elastic fibres by histochemistry; vascular networks [CD31/CD105/nestin] by immunofluorescence; parameters of fibrosis [types I and III collagen, fibronectin, RhoA, alpha-smooth muscle actin [α-SMA], desmin, vimentin], and proliferation [proliferating nuclear antigen [PCNA]] by western blot and/or immunolabelling.
  
  
  RESULTS
  Colonic tissue from both SL-UC and LL-UC showed tunica muscularis thickening and transmural activated neovessels [displaying both proliferating CD105-positive endothelial cells and activated nestin-positive pericytes], as compared with controls. In LL-UC, the increased collagen deposition was associated with an up-regulation of tissue fibrotic markers [collagen I and III, fibronectin, vimentin, RhoA], an enhancement of proliferation [PCNA] and, along with a loss of elastic fibres, a rearrangement of the tunica muscularis towards a fibrotic phenotype.
  
  
  CONCLUSIONS
  A significant transmural fibrotic thickening occurs in colonic tissue from LL-UC, together with a cellular fibrotic switch in the tunica muscularis. A full-thickness angiogenesis is also evident in both SL- and LL-UC with active disease, as compared with controls.
authors.affiliation: Unit of Histology.
authors.forename: Chiara
authors.initials: C
authors.lastname: Ippolito
authors.affiliation: Division of Pharmacology, Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy.
authors.forename: Rocchina
authors.initials: R
authors.lastname: Colucci
authors.affiliation: Unit of Histology.
authors.forename: Cristina
authors.initials: C
authors.lastname: Segnani
authors.affiliation: Unit of Human Anatomy and Histology, Department of Basic Medical Sciences, Neurosciences and Sensory Organs, School of Medicine, University of Bari, Bari, Italy.
authors.forename: Mariella
authors.initials: M
authors.lastname: Errede
authors.affiliation: Unit of Human Anatomy and Histology, Department of Basic Medical Sciences, Neurosciences and Sensory Organs, School of Medicine, University of Bari, Bari, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Girolamo
authors.affiliation: Unit of Human Anatomy and Histology, Department of Basic Medical Sciences, Neurosciences and Sensory Organs, School of Medicine, University of Bari, Bari, Italy.
authors.forename: Daniela
authors.initials: D
authors.lastname: Virgintino
authors.affiliation: Unit of Histology.
authors.forename: Amelio
authors.initials: A
authors.lastname: Dolfi
authors.affiliation: Division of Pharmacology, Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy.
authors.forename: Erika
authors.initials: E
authors.lastname: Tirotta
authors.affiliation: Unit of General Surgery.
authors.forename: Piero
authors.initials: P
authors.lastname: Buccianti
authors.affiliation: Unit of General Surgery.
authors.forename: Giulio
authors.initials: G
authors.lastname: Di Candio
authors.affiliation: Unit of Pathology, University Hospital, Pisa, Italy.
authors.forename: Daniela
authors.initials: D
authors.lastname: Campani
authors.affiliation: Unit of Pathology, University Hospital, Pisa, Italy.
authors.forename: Maura
authors.initials: M
authors.lastname: Castagna
authors.affiliation: Gastroenterology and Hepatology Section, Department of Medicine, University of Perugia, Perugia, Italy.
authors.forename: Gabrio
authors.initials: G
authors.lastname: Bassotti
authors.affiliation: Second Section of Pathology, Spedali Civili, Brescia, Italy.
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Villanacci
authors.affiliation: Division of Pharmacology, Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy.
authors.forename: Corrado
authors.initials: C
authors.lastname: Blandizzi
authors.affiliation: Unit of Histology, nunzia.bernardini@med.unipi.it.
authors.forename: Nunzia
authors.initials: N
authors.lastname: Bernardini
mesh_terms: D000208:Acute Disease; D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000378:metabolism; D015153:Blotting, Western; D016022:Case-Control Studies; D003093:Colitis, Ulcerative / Q000473:pathology*; D003106:Colon / Q000098:blood supply / Q000378:metabolism / Q000473:pathology*; D018450:Disease Progression; D005260:Female; D005355:Fibrosis; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D016037:Single-Blind Method; D066253:Vascular Remodeling
chemical_list: D015415:Biomarkers
keywords: Active disease; colonic muscle remodelling; intestinal angiogenesis; intestinal fibrosis; ulcerative colitis