title: Cinnamaldehyde is the main mediator of cinnamon extract in mast cell inhibition.
abstract: OBJECTIVE
  In terms of their involvement in allergic and inflammatory conditions, mast cells (MC) can be promising targets for medical agents in therapy. Because of their good compliance and effectiveness, phytochemicals are of great interest as new therapeutic tools in form of nutraceuticals. We found recently that cinnamon extract (CE) inhibits mast cell activation. Here, we analysed the effects of a major compound of CE, cinnamaldehyde (CA), on mast cell activation.
  
  
  METHODS
  Release of prestored and de novo synthesised mediators as well as expression of pro-inflammatory cytokines and mast cell-specific proteases were analysed in RBL-2H3 cells or in human mast cells isolated from intestinal tissue (hiMC) treated with CA prior to stimulation by FcεRI crosslinking or IONO/PMA. The results were compared with the corresponding effects of CE.
  
  
  RESULTS
  Following treatment with CA, release of β-hexosaminidase in IgE-dependent or IgE-independent activated RBL-2H3 cells was down-regulated in a dose-dependent manner to about 10%. In hiMC, release of β-hexosaminidase was also significantly reduced, and release of LTC4 and CXCL8 was almost completely inhibited by CA. Moreover, IgE-mediated expression of CXCL8, CCL2, CCL3 and CCL4 in hiMC was significantly down-regulated by CA. With the exception of the expression of the mast cell proteases tryptase and chymase, the inhibitory effects of CA were very similar to the effects shown for CE treatment. The reducing effect of CA on mast cell mediators-seen for long- and for short-term incubations-could be related to particular signalling pathways as CA caused a down-regulation in ERK as well as PLCγ1 phosphorylation.
  
  
  CONCLUSIONS
  CA decreases release and expression of pro-inflammatory mast cell mediators. This inhibitory action is similar to the effects observed for CE indicating CA as the main active compound in CE leading to its anti-allergic properties.
authors.affiliation: Department of Nutritional Medicine, University of Hohenheim, Fruwirthstraße 12, 70593, Stuttgart, Germany.
authors.forename: Yvonne
authors.initials: Y
authors.lastname: Hagenlocher
authors.affiliation: Department of Nutritional Medicine, University of Hohenheim, Fruwirthstraße 12, 70593, Stuttgart, Germany.
authors.forename: Kristina
authors.initials: K
authors.lastname: Kiessling
authors.affiliation: Department of General, Visceral, and Thorax Surgery, Marienhospital Stuttgart, Böheimstraße 37, 70199, Stuttgart, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Schäffer
authors.affiliation: Department of Nutritional Medicine, University of Hohenheim, Fruwirthstraße 12, 70593, Stuttgart, Germany.
authors.forename: Stephan C
authors.initials: SC
authors.lastname: Bischoff
authors.affiliation: Department of Nutritional Medicine, University of Hohenheim, Fruwirthstraße 12, 70593, Stuttgart, Germany. Lorentz@uni-hohenheim.de.
authors.forename: Axel
authors.initials: A
authors.lastname: Lorentz
mesh_terms: D000171:Acrolein / Q000031:analogs & derivatives* / Q000494:pharmacology; D018926:Anti-Allergic Agents / Q000494:pharmacology; D000893:Anti-Inflammatory Agents / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects; D002460:Cell Line; D018932:Chemokine CCL2 / Q000235:genetics / Q000378:metabolism; D054405:Chemokine CCL3 / Q000235:genetics / Q000378:metabolism; D054407:Chemokine CCL4 / Q000235:genetics / Q000378:metabolism; D002935:Cinnamomum zeylanicum / Q000737:chemistry*; D015536:Down-Regulation; D006801:Humans; D007073:Immunoglobulin E / Q000378:metabolism; D016209:Interleukin-8 / Q000235:genetics / Q000378:metabolism; D007422:Intestines / Q000166:cytology / Q000187:drug effects; D017997:Leukotriene C4 / Q000235:genetics / Q000378:metabolism; D008407:Mast Cells / Q000187:drug effects*; D010936:Plant Extracts / Q000737:chemistry* / Q000494:pharmacology; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D017455:Receptors, IgE / Q000378:metabolism; D015398:Signal Transduction; D001619:beta-N-Acetylhexosaminidases / Q000235:genetics / Q000378:metabolism
chemical_list: D018926:Anti-Allergic Agents; D000893:Anti-Inflammatory Agents; C111835:CCL2 protein, human; C515429:CCL3 protein, human; C066507:CCL4 protein, human; C508606:CXCL8 protein, human; D018932:Chemokine CCL2; D054405:Chemokine CCL3; D054407:Chemokine CCL4; D016209:Interleukin-8; D010936:Plant Extracts; D012333:RNA, Messenger; D017455:Receptors, IgE; D017997:Leukotriene C4; D007073:Immunoglobulin E; D000171:Acrolein; D001619:beta-N-Acetylhexosaminidases; C012843:cinnamaldehyde
keywords: Allergy; Cinnamaldehyde; Cinnamon extract; Mast cells; Nutraceuticals