title: Beneficial effects of an amino acid mixture on colonic mucosal healing in rats.
abstract: BACKGROUND
  Mucosal healing (MH) decreases the relapse risk in patients with inflammatory bowel disease, but the role of dietary supplementation in this process has been poorly investigated. Here, we investigated the effect of an amino acid mixture supplement on rat MH.
  
  
  METHODS
  Colitis was induced using 5% of dextran sodium sulfate for 6 days. Then, rats received a mixture of threonine (0.50 g/d), methionine (0.31 g/d), and monosodium glutamate (0.57 g/d) or an isonitrogenous amount of alanine (control group). Colons were recovered after colitis induction and after dietary supplementation for measuring colon characteristics, myeloperoxidase, cytokine gene expression, glutathione content, protein synthesis rate, and for histological analysis. Short-chain fatty acids were measured in the colonic content.
  
  
  RESULTS
  Colitis induction resulted in anorexia, thickening and shortening of the colon, and ulceration. Colonic cytokine expression and neutrophil infiltration were increased. An increased amount of water and a decreased amount of butyrate, propionate, and acetate were measured in the colonic content. Supplementation with the amino acid mixture coincided with a reduced protein synthesis rate in the colon compatible with the observed increased colonic MH. Mucosal regeneration/re-epithelialization was visible within 3 days after colitis induction at a time when mucosal inflammation was severe. Histological analysis revealed an increased regeneration/re-epithelialization after 10-day supplementation. In contrast, the spontaneous resolution of inflammation was not affected by the supplementation.
  
  
  CONCLUSIONS
  Amino acid supplementation ameliorates colonic MH but not mucosal inflammatory status. Our data sustain the use of adjuvant dietary intervention on initiated intestinal MH.
authors.affiliation: *UMR 914 PNCA INRA, AgroParisTech Physiologie de la Nutrition et du Comportement Alimentaire, Paris, France; †Service d'Anatomie et Cytologie Pathologique, Hôpital Xavier Bichat, Paris, France; ‡INSERM U773, Centre de Recherche Biomédicale Bichat Beaujon/Université Paris 7, Paris, France; §Frontier Research Laboratory, Institute for Innovation, Ajinomoto Co. Inc., Kawasaki, Japan; and ‖Departement de Gastroentérologie, Hôpital Avicenne, Assistance Publique-Hôpitaux de Paris, Bobigny, France.
authors.forename: Xinxin
authors.initials: X
authors.lastname: Liu
authors.forename: Martin
authors.initials: M
authors.lastname: Beaumont
authors.forename: Francine
authors.initials: F
authors.lastname: Walker
authors.forename: Catherine
authors.initials: C
authors.lastname: Chaumontet
authors.forename: Mireille
authors.initials: M
authors.lastname: Andriamihaja
authors.forename: Hideki
authors.initials: H
authors.lastname: Matsumoto
authors.forename: Nadezda
authors.initials: N
authors.lastname: Khodorova
authors.forename: Annaïg
authors.initials: A
authors.lastname: Lan
authors.forename: Claire
authors.initials: C
authors.lastname: Gaudichon
authors.forename: Robert
authors.initials: R
authors.lastname: Benamouzig
authors.forename: Daniel
authors.initials: D
authors.lastname: Tomé
authors.forename: Anne-Marie
authors.initials: AM
authors.lastname: Davila
authors.forename: Jean-Claude
authors.initials: JC
authors.lastname: Marie
authors.forename: François
authors.initials: F
authors.lastname: Blachier
mesh_terms: D000596:Amino Acids / Q000008:administration & dosage*; D000818:Animals; D003092:Colitis / Q000139:chemically induced / Q000188:drug therapy* / Q000378:metabolism; D003106:Colon / Q000187:drug effects*; D016264:Dextran Sulfate / Q000633:toxicity; D004195:Disease Models, Animal; D005978:Glutathione / Q000378:metabolism; D007124:Immunoenzyme Techniques; D007413:Intestinal Mucosa / Q000187:drug effects*; D008297:Male; D009195:Peroxidase / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar
chemical_list: D000596:Amino Acids; D016264:Dextran Sulfate; D009195:Peroxidase; D005978:Glutathione