title: Butyrate modulates oxidative stress in the colonic mucosa of healthy humans.
abstract: OBJECTIVE
  Butyrate, a short-chain fatty acid produced by colonic microbial fermentation of undigested carbohydrates, has been implicated in the maintenance of colonic health. This study evaluates whether butyrate plays a role in oxidative stress in the healthy colonic mucosa.
  
  
  METHODS
  A randomized, double blind, cross-over study with 16 healthy volunteers was performed. Treatments consisted of daily rectal administration of a 60 ml enema containing 100 mM sodium butyrate or saline for 2 weeks. After each treatment, a blood sample was taken and mucosal biopsies were obtained from the sigmoid colon. In biopsies, the trolox equivalent antioxidant capacity, activity of glutathione-S-transferase, concentration of uric acid, glutathione (GSH), glutathione disulfide and malondialdehyde, and expression of genes involved in GSH and uric acid metabolism was determined. Secondary outcome parameters were CRP, calprotectin and intestinal fatty acid binding protein in plasma and histological inflammatory scores.
  
  
  RESULTS
  Butyrate treatment resulted in significantly higher GSH (p<0.05) and lower uric acid (p<0.01) concentrations compared to placebo. Changes in GSH and uric acid were accompanied by increased and decreased expression, respectively, of their rate limiting enzymes determined by RT-PCR. No significant differences were found in other parameters.
  
  
  CONCLUSIONS
  This study demonstrated that butyrate is able to beneficially affect oxidative stress in the healthy human colon.
authors.affiliation: TI Food and Nutrition, Wageningen, The Netherlands. h.hamer@intmed.unimaas.nl
authors.forename: Henrike M
authors.initials: HM
authors.lastname: Hamer
authors.forename: Daisy M A E
authors.initials: DM
authors.lastname: Jonkers
authors.forename: Aalt
authors.initials: A
authors.lastname: Bast
authors.forename: Steven A L W
authors.initials: SA
authors.lastname: Vanhoutvin
authors.forename: Marc A J G
authors.initials: MA
authors.lastname: Fischer
authors.forename: Andrea
authors.initials: A
authors.lastname: Kodde
authors.forename: Freddy J
authors.initials: FJ
authors.lastname: Troost
authors.forename: Koen
authors.initials: K
authors.lastname: Venema
authors.forename: Robert-Jan M
authors.initials: RJ
authors.lastname: Brummer
mesh_terms: D000293:Adolescent; D000328:Adult; D001706:Biopsy; D002087:Butyrates / Q000494:pharmacology*; D003106:Colon / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D018592:Cross-Over Studies; D004311:Double-Blind Method; D004733:Enema; D005260:Female; D005978:Glutathione / Q000378:metabolism*; D006801:Humans; D007413:Intestinal Mucosa / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D018384:Oxidative Stress / Q000187:drug effects*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017392:Thiobarbituric Acid Reactive Substances / Q000032:analysis; D014527:Uric Acid / Q000378:metabolism*; D055815:Young Adult
chemical_list: D002087:Butyrates; D017392:Thiobarbituric Acid Reactive Substances; D014527:Uric Acid; D005978:Glutathione