title: Chrysin protects epidermal keratinocytes from UVA- and UVB-induced damage.
abstract: Chrysin (5,7-dihydroxyflavone), a natural flavonoid occurring in various plants and foods such as propolis and honey, reportedly opposes inflammation and carcinogenesis, but has rarely been applied in skin care. This study, therefore, aimed to explore the roles of chrysin in protection against UV-induced damage in HaCaT keratinocytes. Results showed that chrysin can attenuate apoptosis, reactive oxygen species (ROS) production, and cyclooxygenase 2 (COX-2) expression induced by UVB and UVA. Chrysin predominantly reversed the down-regulation of aquaporin 3 (AQP-3) by UVB. It predominantly reversed JNK activation and also mildly inhibited p38 activation triggered by UVA and UVB. Animal studies revealed that chrysin's topical application demonstrated efficient percutaneous absorption and no skin irritation. Overall, results demonstrated significant benefits of chrysin on the protection of keratinocytes against UVA- and UVB-induced injuries and suggested its potential use in skin photoprotection.
authors.affiliation: Department of Dermatology, Mackay Memorial Hospital, Hsinchu, Taiwan.
authors.forename: Nan-Lin
authors.initials: NL
authors.lastname: Wu
authors.forename: Jia-You
authors.initials: JY
authors.lastname: Fang
authors.forename: Marcelo
authors.initials: M
authors.lastname: Chen
authors.forename: Chia-Jung
authors.initials: CJ
authors.lastname: Wu
authors.forename: Chieh-Chen
authors.initials: CC
authors.lastname: Huang
authors.forename: Chi-Feng
authors.initials: CF
authors.lastname: Hung
mesh_terms: D017209:Apoptosis / Q000528:radiation effects; D002460:Cell Line; D051546:Cyclooxygenase 2 / Q000378:metabolism; D000078404:Epidermal Cells; D004817:Epidermis / Q000187:drug effects / Q000378:metabolism / Q000528:radiation effects; D005419:Flavonoids / Q000494:pharmacology*; D006801:Humans; D015603:Keratinocytes / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism / Q000528:radiation effects*; D011837:Radiation-Protective Agents / Q000494:pharmacology*; D017382:Reactive Oxygen Species / Q000378:metabolism; D014466:Ultraviolet Rays
chemical_list: D005419:Flavonoids; D011837:Radiation-Protective Agents; D017382:Reactive Oxygen Species; C043561:chrysin; D051546:Cyclooxygenase 2