title: Protective effect of triphlorethol-A against ultraviolet B-mediated damage of human keratinocytes.
abstract: Ultraviolet B (UVB) radiation on human skin induces pathophysiological processes such as oxidative stress and inflammation. In previous reports, the antioxidant effects of triphlorethol-A were shown to protect cells against hydrogen peroxide-induced cell damage and gamma ray-induced oxidative stress. In this study, the role of triphlorethol-A in protecting human keratinocytes (HaCaT) against UVB-induced cell damage was investigated. Triphlorethol-A-treated cells were irradiated with UVB (150 mJ/cm(2)). Triphlorethol-A decreased UVB-induced intracellular ROS and restored the activities of antioxidant enzymes decreased by UVB radiation. Triphlorethol-A decreased UVB damage to cellular components, such as lipid membrane and DNA, restored cell viability and reduced UVB-induced apoptosis by inhibiting the mitochondria-mediated caspase pathway. Triphlorethol-A also reduced the UVB-induced loss of ΔΨ(m) and the active forms of caspase 9 and caspase 3. The anti-apoptotic effect of triphlorethol-A was found to involve the inhibition of c-Jun NH(2)-terminal kinase, which was induced by UVB exposure. And triphlorethol-A showed an absorptive capacity at range of UVB. These results suggest that triphlorethol-A protects human keratinocytes against UVB by enhancing the activities of the antioxidant system, inhibiting cellular damage and absorbing the UVB.
authors.affiliation: School of Medicine, Jeju National University, Jeju 690-756, South Korea.
authors.forename: Mei Jing
authors.initials: MJ
authors.lastname: Piao
authors.forename: Rui
authors.initials: R
authors.lastname: Zhang
authors.forename: Nam Ho
authors.initials: NH
authors.lastname: Lee
authors.forename: Jin Won
authors.initials: JW
authors.lastname: Hyun
mesh_terms: D000975:Antioxidants / Q000737:chemistry / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects / Q000528:radiation effects; D020169:Caspases / Q000378:metabolism; D002460:Cell Line; D004249:DNA Damage; D004798:Enzymes / Q000378:metabolism; D006801:Humans; D048031:JNK Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism; D015603:Keratinocytes / Q000187:drug effects* / Q000528:radiation effects; D015227:Lipid Peroxidation; D010696:Phloroglucinol / Q000031:analogs & derivatives* / Q000737:chemistry / Q000494:pharmacology; D017382:Reactive Oxygen Species / Q000378:metabolism; D015398:Signal Transduction; D014466:Ultraviolet Rays
chemical_list: D000975:Antioxidants; D004798:Enzymes; D017382:Reactive Oxygen Species; C504400:triphlorethol-A; D010696:Phloroglucinol; D048031:JNK Mitogen-Activated Protein Kinases; D020169:Caspases