title: Impact of the arylhydrocarbon receptor on eugenol- and isoeugenol-induced cell cycle arrest in human immortalized keratinocytes (HaCaT).
abstract: Fragrances such as eugenol (4-allyl-2-methoxyphenol) and isoeugenol (2-methoxy-4-propenylphenol), naturally found in reasonable quantities in the essential oils of different spices, are not only common causes of contact dermatitis but also known for their antiproliferative actions. Previously, we found a cell cycle arrest and an arylhydrocarbon receptor (AhR)-mediated activation of cytochromes in immortalized keratinocytes (HaCaT) induced by both compounds. In the present study we investigated whether the cell cycle arrest of eugenol and isoeugenol is mediated by the AhR in HaCaT cells. Analysis of the cell cycle status by fluorescence-activated cell sorting (FACS) revealed an arrest of cells (32-34%) in the G0/G1 phase induced by both compounds. This was found in synchronized HaCaT cells, natural HaCaT, and siRNA AhR transfected HaCaT. The induced G0/G1 arrests were reduced in the presence of the highly selective AhR antagonist 3'-methoxy-4'-nitroflavone (MNF). In summary, these results, together with our previous findings that both compounds induce translocation of the AhR into the nucleus, provide good evidence that the effects of eugenol and isoeugenol in skin and keratinocytes are mediated by the AhR. Furthermore, these data suggest that the known growth suppressive effects of these compounds in some skin cells may be mediated by AhR interactions.
authors.affiliation: Department for Ecotoxicology and Toxicology, University of Trier, D-54296 Trier, Germany.
authors.forename: Michaela
authors.initials: M
authors.lastname: Kalmes
authors.forename: Andrea
authors.initials: A
authors.lastname: Neumeyer
authors.forename: Paola
authors.initials: P
authors.lastname: Rio
authors.forename: Helmut
authors.initials: H
authors.lastname: Hanenberg
authors.forename: Ellen
authors.initials: E
authors.lastname: Fritsche
authors.forename: Brunhilde
authors.initials: B
authors.lastname: Blömeke
mesh_terms: D001564:Benzo(a)pyrene / Q000494:pharmacology; D002453:Cell Cycle / Q000187:drug effects*; D002460:Cell Line; D019363:Cytochrome P-450 CYP1A1 / Q000187:drug effects / Q000235:genetics; D004121:Dimethyl Sulfoxide / Q000494:pharmacology; D005054:Eugenol / Q000031:analogs & derivatives* / Q000494:pharmacology*; D006801:Humans; D015603:Keratinocytes / Q000187:drug effects* / Q000378:metabolism; D012333:RNA, Messenger / Q000187:drug effects / Q000235:genetics; D018336:Receptors, Aryl Hydrocarbon / Q000187:drug effects* / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods; D013329:Structure-Activity Relationship
chemical_list: D012333:RNA, Messenger; D018336:Receptors, Aryl Hydrocarbon; D001564:Benzo(a)pyrene; D005054:Eugenol; C036643:isoeugenol; D019363:Cytochrome P-450 CYP1A1; D004121:Dimethyl Sulfoxide