title: Photo-protective effect of americanin B against ultraviolet B-induced damage in cultured human keratinocytes.
abstract: Excessive ultraviolet (UV) radiation, a constituent of sunlight, can induce multiple types of skin damage. We recently demonstrated that americanin B, a lignin compound, protected cells against hydrogen peroxide (H2O2)-induced damage by exerting antioxidant effects and inhibiting apoptosis. In this study, we investigated the ability of americanin B to protect against cell injury induced by UVB (280-320nm), the most harmful UV wavelengths, in human HaCaT keratinocytes. Americanin B absorbed UVB, eliminated UVB-induced intracellular reactive oxygen species (ROS), and decreased the extent of UVB-induced oxidative modification of lipids, proteins, and DNA. In addition, americanin B inhibited UVB-induced apoptosis, as indicated by reductions in apoptotic body formation and DNA fragmentation. Furthermore, americanin B reversed the depolarization of the mitochondrial membrane induced by UVB exposure. These protective activities were associated with down-regulation of apoptosis-promoting proteins, Bax, caspase-9, and caspase-3 and up-regulation of an apoptosis inhibitor, Bcl-2. These results suggest that americanin B can protect human keratinocytes against UVB-induced cell damage.
authors.affiliation: School of Medicine and Institute for Nuclear Science and Technology, Jeju National University, Jeju 690-756, Republic of Korea.
authors.forename: Jian
authors.initials: J
authors.lastname: Zheng
authors.affiliation: School of Medicine and Institute for Nuclear Science and Technology, Jeju National University, Jeju 690-756, Republic of Korea.
authors.forename: Mei Jing
authors.initials: MJ
authors.lastname: Piao
authors.affiliation: School of Medicine and Institute for Nuclear Science and Technology, Jeju National University, Jeju 690-756, Republic of Korea.
authors.forename: Ki Cheon
authors.initials: KC
authors.lastname: Kim
authors.affiliation: School of Medicine and Institute for Nuclear Science and Technology, Jeju National University, Jeju 690-756, Republic of Korea.
authors.forename: Cheng Wen
authors.initials: CW
authors.lastname: Yao
authors.affiliation: School of Medicine and Institute for Nuclear Science and Technology, Jeju National University, Jeju 690-756, Republic of Korea.
authors.forename: Ji Won
authors.initials: JW
authors.lastname: Cha
authors.affiliation: Department of Mechanical Engineering & Graduate School of Medical Science and Engineering, KAIST, Daejeon 305-701, Republic of Korea.
authors.forename: Jennifer H
authors.initials: JH
authors.lastname: Shin
authors.affiliation: National Fusion Research Institute, Plasma Technology Research Center, Gunsan 573-540, Republic of Korea.
authors.forename: Suk Jae
authors.initials: SJ
authors.lastname: Yoo
authors.affiliation: School of Medicine and Institute for Nuclear Science and Technology, Jeju National University, Jeju 690-756, Republic of Korea. Electronic address: jinwonh@jejunu.ac.kr.
authors.forename: Jin Won
authors.initials: JW
authors.lastname: Hyun
mesh_terms: D000975:Antioxidants / Q000494:pharmacology*; D017209:Apoptosis; D002470:Cell Survival; D002478:Cells, Cultured; D004249:DNA Damage / Q000187:drug effects*; D004146:Dioxanes / Q000494:pharmacology*; D005786:Gene Expression Regulation / Q000187:drug effects; D006801:Humans; D015603:Keratinocytes / Q000166:cytology / Q000187:drug effects / Q000528:radiation effects; D015227:Lipid Peroxidation / Q000187:drug effects; D018384:Oxidative Stress / Q000187:drug effects; D014466:Ultraviolet Rays
chemical_list: D000975:Antioxidants; D004146:Dioxanes; C000598877:americanin B
keywords: Americanin B; Apoptosis; Human keratinocytes; Oxidative stress; Ultraviolet B