title: Isoflavones regulate innate immunity and inhibit experimental colitis.
abstract: OBJECTIVE
  Dysregulated immune responses in the gut to luminal antigens can cause inflammatory bowel diseases (IBD). The roles played by dietary antigens in the pathogenesis or prevention of IBD are poorly understood. Soybean isoflavones are digested in large amounts and have many biological activities. The aim of this study was to determine whether isoflavones in aglycon and bioavailable forms have any effect on gut immunity and protect the host from tissue damage in a mouse model of colitis.
  
  
  METHODS
  We administered daidzein-rich isoflavone aglycones (DRIA) to mice for 1 week and then treated them with 2% dextran sodium sulfate (DSS) in drinking water for 4 days to induce colitis. The effect of DRIA was evaluated by examining the histopathology of the colon, body weight changes, and functional analysis of mesenteric lymph node cells (MLN).
  
  
  RESULTS
  DRIA inhibited interleukin (IL)-6 and IL-8 production by Toll-like receptor (TLR)2, and TLR4-stimulated monocytes in a dose-dependent manner. The mice administered DRIA had less inflammation and tissue damage in the colon than the control mice. This protective effect of DRIA was associated with a decrease in interferon-gamma, IL-6, and IL-12p40 secretion, and an increase in IL-10 secretion and low cell-activation status of antigen-presenting cells (APC) in MLN.
  
  
  CONCLUSIONS
  Ingested DRIA can downregulate the functions of APC and inhibit DSS colitis.
authors.affiliation: Department of Clinical Bio-regulatory Science, Kyoto University Graduate School of Medicine, Kyoto, Japan.
authors.forename: Masakazu
authors.initials: M
authors.lastname: Morimoto
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Watanabe
authors.forename: Masashi
authors.initials: M
authors.lastname: Yamori
authors.forename: Minoru
authors.initials: M
authors.lastname: Takebe
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Wakatsuki
mesh_terms: D000818:Animals; D003092:Colitis / Q000188:drug therapy* / Q000276:immunology*; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D015536:Down-Regulation; D004797:Enzyme-Linked Immunosorbent Assay; D005434:Flow Cytometry; D007113:Immunity, Innate; D007371:Interferon-gamma / Q000378:metabolism; D016753:Interleukin-10 / Q000378:metabolism; D018664:Interleukin-12 / Q000378:metabolism; D015850:Interleukin-6 / Q000378:metabolism; D016209:Interleukin-8 / Q000378:metabolism; D007529:Isoflavones / Q000494:pharmacology*; D051379:Mice; D018709:Statistics, Nonparametric; D051195:Toll-Like Receptor 2 / Q000378:metabolism; D051197:Toll-Like Receptor 4 / Q000378:metabolism
chemical_list: D015850:Interleukin-6; D016209:Interleukin-8; D007529:Isoflavones; D051195:Toll-Like Receptor 2; D051197:Toll-Like Receptor 4; D016753:Interleukin-10; D018664:Interleukin-12; C004742:daidzein; D007371:Interferon-gamma