title: Histological changes in the colonic mucosa following irrigation with short-chain fatty acids.
abstract: OBJECTIVE
  Short-chain fatty acids (SCFAs) derived from bacterial fermentation of complex carbohydrates are preferred luminal nutrients of the colonic mucosa. Starvation of colonocytes through lack or impaired metabolism of luminal SCFAs may be a cofactor in the pathogenesis of ulcerative colitis.
  
  
  METHODS
  A detailed histological evaluation of colonic biopsy specimens was performed in patients with active distal ulcerative colitis who were treated with rectal enemas containing a mixture of SCFAs, n-butyrate alone or saline placebo. Together with light microscopic parameters of mucosal inflammation, the pattern of crypt cell proliferation (proliferating cell nuclear antigen) and the mucosal activity of factor XIII were assessed.
  
  
  RESULTS
  Butyrate reduced the density of polymorphonuclear leucocytes in the lamina propria (4 weeks: P = 0.063; 8 weeks: P = 0.091); other inflammatory parameters remained unchanged. Both butyrate and the SCFA mixture reduced significantly the number of proliferating cells in the upper 40% of crypts. Tissue factor XIII activity in active ulcerative colitis was significantly lower than in mucosa from normal colons; however, it was not affected by SCFA or butyrate irrigation.
  
  
  CONCLUSIONS
  SCFAs and butyrate have a more marked effect on crypt cell proliferation than on parameters of inflammation in patients with active ulcerative colitis.
authors.affiliation: Department of Medicine, University of Würzburg, Germany.
authors.forename: W
authors.initials: W
authors.lastname: Scheppach
authors.forename: J G
authors.initials: JG
authors.lastname: Müller
authors.forename: F
authors.initials: F
authors.lastname: Boxberger
authors.forename: G
authors.initials: G
authors.lastname: Dusel
authors.forename: F
authors.initials: F
authors.lastname: Richter
authors.forename: H P
authors.initials: HP
authors.lastname: Bartram
authors.forename: S U
authors.initials: SU
authors.lastname: Christl
authors.forename: C E
authors.initials: CE
authors.lastname: Dempfle
authors.forename: H
authors.initials: H
authors.lastname: Kasper
mesh_terms: D000328:Adult; D001706:Biopsy; D002087:Butyrates / Q000008:administration & dosage / Q000627:therapeutic use; D020148:Butyric Acid; D003093:Colitis, Ulcerative / Q000378:metabolism / Q000473:pathology / Q000628:therapy*; D004733:Enema; D005176:Factor XIII / Q000378:metabolism; D005232:Fatty Acids, Volatile / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D007413:Intestinal Mucosa / Q000378:metabolism / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D018809:Proliferating Cell Nuclear Antigen / Q000378:metabolism; D016896:Treatment Outcome
chemical_list: D002087:Butyrates; D005232:Fatty Acids, Volatile; D018809:Proliferating Cell Nuclear Antigen; D020148:Butyric Acid; D005176:Factor XIII