title: Chafuroside B, an Oolong tea polyphenol, ameliorates UVB-induced DNA damage and generation of photo-immunosuppression related mediators in human keratinocytes.
abstract: Chafuroside B was recently isolated as a new polyphenolic constituent of oolong tea leaves. However, the effects of chafuroside B on skin function have not been examined. In this study, we investigated the protective effects of chafuroside B against UVB-induced DNA damage, apoptosis and generation of photo-immunosuppression related mediators in cultured normal human epidermal keratinocytes (NHEK). Chafuroside B at 1 µM attenuated both UVB-induced apoptosis, evaluated in terms of caspase-3/7 activity, and UVB-induced DNA damage, evaluated in terms of formation of cyclobutane pyrimidine dimers (CPD), in NHEK exposed to UVB (20 mJ/cm2). In addition, chafuroside B at 0.3 or 1 µM suppressed the UVB-induced production of interleukin (IL)-10, tumor necrosis factor (TNF)-α, and prostaglandin E2 (PGE2), as determined by ELISA, and conversely enhanced IL-12 mRNA expression and production, as measured by RT-PCR and ELISA. Further, chafuroside B at 1 µM also suppressed UVB-induced expression of receptor activator of nuclear factor κB ligand (RANKL) mRNA. These results indicate that chafuroside B promotes repair of UVB-induced DNA damage and ameliorates the generation of IL-10, TNF-α, PGE2, and RANKL, all of which are UVB-induced immunosuppression related mediators. These effects of chafuroside B may be mediated at least in part through induction of IL-12 synthesis in human keratinocytes. Because chafuroside B might have practical value as a photoprotective agent, a further study of the in vivo effects of chafuroside B seems warranted.
authors.affiliation: Functional Food Research and Development Center, Shiseido Research Center, Yokohama, Kanagawa, Japan.
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Hasegawa
authors.forename: Shoichiro
authors.initials: S
authors.lastname: Shimada
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Ishida
authors.forename: Masaya
authors.initials: M
authors.lastname: Nakashima
mesh_terms: D017209:Apoptosis / Q000187:drug effects; D053148:Caspase 3 / Q000378:metabolism; D002460:Cell Line; D004249:DNA Damage / Q000187:drug effects* / Q000528:radiation effects; D015232:Dinoprostone / Q000276:immunology; D047309:Flavones / Q000737:chemistry / Q000494:pharmacology*; D006576:Heterocyclic Compounds, 4 or More Rings / Q000737:chemistry / Q000494:pharmacology*; D006801:Humans; D007165:Immunosuppression Therapy; D007166:Immunosuppressive Agents / Q000737:chemistry / Q000494:pharmacology*; D016753:Interleukin-10 / Q000276:immunology; D015603:Keratinocytes / Q000166:cytology / Q000187:drug effects* / Q000276:immunology / Q000528:radiation effects*; D013662:Tea / Q000737:chemistry; D014409:Tumor Necrosis Factor-alpha / Q000276:immunology; D014466:Ultraviolet Rays
chemical_list: C510948:3,4,11-trihydroxy-2-(hydroxymethyl)-8-(4-hydroxyphenyl)-3,4,4a,11b-tetrahydro-2H,10H-pyrano(2',3'-4,5)furo(3,2-g)chromen-10-one; D047309:Flavones; D006576:Heterocyclic Compounds, 4 or More Rings; D007166:Immunosuppressive Agents; D013662:Tea; D014409:Tumor Necrosis Factor-alpha; D016753:Interleukin-10; D053148:Caspase 3; D015232:Dinoprostone