title: Suppression of gamma-tocotrienol on UVB induced inflammation in HaCaT keratinocytes and HR-1 hairless mice via inflammatory mediators multiple signaling.
abstract: Tocopherol (Toc) such as alpha-Toc has been expected to act as photochemopreventive agent of skin, but the effect of the other vitamin E forms [tocotrienols (T3)] has not been fully understood. We evaluated the anti-inflammatory effect of T3 on UVB-induced inflammatory reaction using immortalized human keratinocytes and hairless mice. gamma-T3 suppressed UVB-induced PGE(2) production while similar alpha-Toc doses had no effect. The anti-inflammatory actions of gamma-T3 were explained by its ability to reduce UVB-induced inflammatory gene and protein expression [cyclooxgenase-2 (COX-2), interleukin (IL)-1beta, IL-6, and monocyte chemotactic protein-1]. Western blot analysis revealed gamma-T3 inhibited p38, extracellular signal-regulated kinase, and c-Jun N-terminal kinase/stress-activated protein kinase activation. In HR-1 hairless mice, oral T3 suppressed UVB-induced changes in skin thickness, COX-2 protein expression, and hyperplasia, but alpha-Toc did not. These results suggest T3 has potential use to protect against UVB-induced skin inflammation.
authors.affiliation: Food and Biodynamic Chemistry Laboratory, Graduate School of Agricultural Science, Tohoku University, Sendai 981-8555, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Shibata
authors.forename: Kiyotaka
authors.initials: K
authors.lastname: Nakagawa
authors.forename: Yuki
authors.initials: Y
authors.lastname: Kawakami
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Tsuzuki
authors.forename: Teruo
authors.initials: T
authors.lastname: Miyazawa
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D018932:Chemokine CCL2 / Q000235:genetics / Q000276:immunology; D002839:Chromans / Q000494:pharmacology*; D051546:Cyclooxygenase 2 / Q000235:genetics / Q000378:metabolism; D015536:Down-Regulation; D005260:Female; D015870:Gene Expression / Q000187:drug effects / Q000528:radiation effects; D006801:Humans; D018836:Inflammation Mediators / Q000276:immunology*; D015850:Interleukin-6 / Q000235:genetics / Q000276:immunology; D015603:Keratinocytes / Q000187:drug effects / Q000276:immunology* / Q000378:metabolism / Q000528:radiation effects*; D020935:MAP Kinase Signaling System / Q000187:drug effects / Q000528:radiation effects; D051379:Mice; D008812:Mice, Hairless; D011837:Radiation-Protective Agents / Q000494:pharmacology*; D014466:Ultraviolet Rays; D014810:Vitamin E / Q000031:analogs & derivatives* / Q000494:pharmacology
chemical_list: D018932:Chemokine CCL2; D002839:Chromans; D018836:Inflammation Mediators; D015850:Interleukin-6; D011837:Radiation-Protective Agents; D014810:Vitamin E; C013649:plastochromanol 8; D051546:Cyclooxygenase 2