title: Proinflammatory cytokines induce amelotin transcription in human gingival fibroblasts.
abstract: Amelotin (AMTN) is a secreted protein transcribed predominantly during the maturation stage of enamel formation and localized in the junctional epithelium. We investigated differences in the levels of AMTN gene expression between non-inflamed gingiva and inflamed gingiva from patients with chronic periodontitis. Total RNAs were isolated from these tissues and their gene expression profiles were monitored by DNA microarray. The observed induction of AMTN mRNA in inflamed gingiva and cultured human gingival fibroblasts (HGF) was confirmed by real-time PCR. Transient transfection assays were performed using chimeric constructs of mouse AMTN gene promoter fragments linked to a luciferase reporter gene. Immunohistochemical localization of AMTN in inflamed and non-inflamed gingiva was assessed by immunohistochemistry. Among many differentially expressed genes, the level of AMTN mRNA was significantly increased in inflamed gingiva. Treatment of HGF with interleukin-1β (IL-1β), IL-6 and tumor necrosis factor-α (TNF-α) induced the expression of AMTN mRNA, and increased the luciferase activities of the AMTN promoter constructs. AMTN protein was detected in inflamed gingival connective tissue and junctional epithelium. These findings demonstrate that proinflammatory cytokines induce AMTN gene expression in human gingival fibroblasts and suggest a role for AMTN in gingival inflammation.
authors.affiliation: Department of Periodontology, Nihon University School of Dentistry at Matsudo.
authors.forename: Yohei
authors.initials: Y
authors.lastname: Nakayama
authors.forename: Hideki
authors.initials: H
authors.lastname: Takai
authors.forename: Sari
authors.initials: S
authors.lastname: Matsui
authors.forename: Hiroyoshi
authors.initials: H
authors.lastname: Matsumura
authors.forename: Liming
authors.initials: L
authors.lastname: Zhou
authors.forename: Ayako
authors.initials: A
authors.lastname: Kato
authors.forename: Bernhard
authors.initials: B
authors.lastname: Ganss
authors.forename: Yorimasa
authors.initials: Y
authors.lastname: Ogata
mesh_terms: D000328:Adult; D000818:Animals; D002478:Cells, Cultured; D002678:Chimera / Q000235:genetics; D055113:Chronic Periodontitis / Q000235:genetics / Q000473:pathology; D003238:Connective Tissue / Q000737:chemistry; D016207:Cytokines / Q000494:pharmacology*; D003746:Dental Enamel Proteins / Q000032:analysis / Q000187:drug effects* / Q000235:genetics; D004846:Epithelial Attachment / Q000737:chemistry; D005260:Female; D005347:Fibroblasts / Q000737:chemistry / Q000187:drug effects*; D020869:Gene Expression Profiling; D017930:Genes, Reporter / Q000235:genetics; D005881:Gingiva / Q000737:chemistry / Q000166:cytology / Q000187:drug effects*; D005891:Gingivitis / Q000235:genetics / Q000473:pathology; D006801:Humans; D018836:Inflammation Mediators / Q000494:pharmacology*; D053583:Interleukin-1beta / Q000494:pharmacology; D008156:Luciferases / Q000235:genetics; D008297:Male; D051379:Mice; D046228:Microarray Analysis; D008875:Middle Aged; D011401:Promoter Regions, Genetic / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D014158:Transcription, Genetic / Q000187:drug effects*; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
chemical_list: C507067:AMTN protein, human; D016207:Cytokines; D003746:Dental Enamel Proteins; D018836:Inflammation Mediators; D053583:Interleukin-1beta; D014409:Tumor Necrosis Factor-alpha; D008156:Luciferases