title: Cinnamon extract suppresses experimental colitis through modulation of antigen-presenting cells.
abstract: OBJECTIVE
  To investigate the anti-inflammatory effects of cinnamon extract and elucidate its mechanisms for targeting the function of antigen presenting cells.
  
  
  METHODS
  Cinnamon extract was used to treat murine macrophage cell line (Raw 264.7), mouse primary antigen-presenting cells (APCs, MHCII(+)) and CD11c(+) dendritic cells to analyze the effects of cinnamon extract on APC function. The mechanisms of action of cinnamon extract on APCs were investigated by analyzing cytokine production, and expression of MHC antigens and co-stimulatory molecules by quantitative real-time PCR and flow cytometry. In addition, the effect of cinnamon extract on antigen presentation capacity and APC-dependent T-cell differentiation were analyzed by [H(3)]-thymidine incorporation and cytokine analysis, respectively. To confirm the anti-inflammatory effects of cinnamon extract in vivo, cinnamon or PBS was orally administered to mice for 20 d followed by induction of experimental colitis with 2,4,6 trinitrobenzenesulfonic acid. The protective effects of cinnamon extract against experimental colitis were measured by checking clinical symptoms, histological analysis and cytokine expression profiles in inflamed tissue.
  
  
  RESULTS
  Treatment with cinnamon extract inhibited maturation of MHCII(+) APCs or CD11c(+) dendritic cells (DCs) by suppressing expression of co-stimulatory molecules (B7.1, B7.2, ICOS-L), MHCII and cyclooxygenase (COX)-2. Cinnamon extract induced regulatory DCs (rDCs) that produce low levels of pro-inflammatory cytokines [interleukin (IL)-1β, IL-6, IL-12, interferon (IFN)-γ and tumor necrosis factor (TNF)-α] while expressing high levels of immunoregulatory cytokines (IL-10 and transforming growth factor-β). In addition, rDCs generated by cinnamon extract inhibited APC-dependent T-cell proliferation, and converted CD4(+) T cells into IL-10(high) CD4(+) T cells. Furthermore, oral administration of cinnamon extract inhibited development and progression of intestinal colitis by inhibiting expression of COX-2 and pro-inflammatory cytokines (IL-1β, IFN-γ and TNF-α), while enhancing IL-10 levels.
  
  
  CONCLUSIONS
  Our study suggests the potential of cinnamon extract as an anti-inflammatory agent by targeting the generation of regulatory APCs and IL-10(+) regulatory T cells.
authors: School of Life Sciences and Immune Synapse Research Center, Gwangju Institute of Science and Technology, South Korea.
authors: Ho-Keun
authors: HK
authors: Kwon
authors: Ji-Sun
authors: JS
authors: Hwang
authors: Choong-Gu
authors: CG
authors: Lee
authors: Jae-Seon
authors: JS
authors: So
authors: Anupama
authors: A
authors: Sahoo
authors: Chang-Rok
authors: CR
authors: Im
authors: Won Kyung
authors: WK
authors: Jeon
authors: Byoung Seob
authors: BS
authors: Ko
authors: Sung Haeng
authors: SH
authors: Lee
authors: Zee Yong
authors: ZY
authors: Park
authors: Sin-Hyeog
authors: SH
authors: Im
mesh_terms: D000818:Animals; D000893:Anti-Inflammatory Agents / Q000494:pharmacology / Q000627:therapeutic use; D000938:Antigen-Presenting Cells / Q000166:cytology / Q000187:drug effects* / Q000276:immunology; D002460:Cell Line; D049109:Cell Proliferation / Q000187:drug effects; D002935:Cinnamomum zeylanicum / Q000737:chemistry*; D003092:Colitis / Q000139:chemically induced / Q000188:drug therapy* / Q000276:immunology*; D003713:Dendritic Cells / Q000166:cytology / Q000187:drug effects / Q000276:immunology; D016753:Interleukin-10 / Q000276:immunology; D008264:Macrophages / Q000166:cytology / Q000187:drug effects / Q000276:immunology; D008297:Male; D008518:Medicine, East Asian Traditional; D051379:Mice; D008810:Mice, Inbred C57BL; D010936:Plant Extracts / Q000494:pharmacology* / Q000627:therapeutic use*; D050378:T-Lymphocytes, Regulatory / Q000276:immunology
chemical_list: D000893:Anti-Inflammatory Agents; D010936:Plant Extracts; D016753:Interleukin-10