title: Pretreatment with alanyl-glutamine suppresses T-helper-cell-associated cytokine expression and reduces inflammatory responses in mice with acute DSS-induced colitis.
abstract: T-helper (Th) cells play a major role in initiating and shaping the pathologic response in inflammatory bowel disease (IBD). Glutamine (GLN) is a nutrient with immune-modulating effects. This study investigated the effect of GLN on cytokine expressions and inflammatory responses of three subsets of Th cells in dextran sulfate sodium (DSS)-induced IBD. There were one normal control (NC) and two DSS groups. Mice in the DSS groups drank distilled water containing 3% DSS for 5 days, whereas the NC group received distilled water. Mice in the G-DSS group were given intraperitoneal injection of 0.5 g GLN/kg/d for 3 days before receiving DSS water. The other DSS group (C-DSS) received an identical amount of amino acid solution without GLN. After induction of IBD, the mice were allowed to recover for 3 days and then were sacrificed. Blood and colon samples were collected for further analysis. The C-DSS group had higher percentages of blood interleukin (IL)-17A, IL-17F, IL-22, IL-4 and interferon-γ than the NC group. The G-DSS group had lower Th1/Th17/Th2 cytokine expressions, which showed no differences from the NC group. Plasma haptoglobin, colon immunoglobin G and chemokine levels and myeloperoxidase activities were higher in the DSS groups than the NC group. These parameters were significantly lower in the G-DSS than the C-DSS group. These results suggest that pretreatment with GLN suppressed Th-associated cytokine expressions and may consequently reduce inflammatory mediator production and leukocyte infiltration into tissues, thus ameliorating the severity of acute DSS-induced colitis.
authors.affiliation: Graduate Institute of Pharmacy, Taipei Medical University, Taipei, Taiwan.
authors.forename: Chia-Chou
authors.initials: CC
authors.lastname: Chu
authors.forename: Yu-Chen
authors.initials: YC
authors.lastname: Hou
authors.forename: Man-Hui
authors.initials: MH
authors.lastname: Pai
authors.forename: Chen-Jui
authors.initials: CJ
authors.lastname: Chao
authors.forename: Sung-Ling
authors.initials: SL
authors.lastname: Yeh
mesh_terms: D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage / Q000627:therapeutic use*; D003092:Colitis / Q000097:blood / Q000188:drug therapy / Q000276:immunology / Q000503:physiopathology; D003093:Colitis, Ulcerative / Q000209:etiology / Q000517:prevention & control; D003106:Colon / Q000187:drug effects* / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D016207:Cytokines / Q000097:blood* / Q000378:metabolism; D016264:Dextran Sulfate; D004151:Dipeptides / Q000008:administration & dosage / Q000627:therapeutic use*; D004195:Disease Models, Animal; D015536:Down-Regulation / Q000187:drug effects*; D006242:Haptoglobins / Q000032:analysis; D015212:Inflammatory Bowel Diseases / Q000276:immunology / Q000473:pathology / Q000503:physiopathology / Q000517:prevention & control*; D007274:Injections, Intraperitoneal; D007413:Intestinal Mucosa / Q000187:drug effects / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009195:Peroxidase / Q000378:metabolism; D012720:Severity of Illness Index; D006377:T-Lymphocytes, Helper-Inducer / Q000187:drug effects* / Q000276:immunology / Q000378:metabolism / Q000473:pathology
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D016207:Cytokines; D004151:Dipeptides; D006242:Haptoglobins; D016264:Dextran Sulfate; D009195:Peroxidase; C054122:alanylglutamine