title: Protective effect of the ethyl acetate fraction of Sargassum muticum against ultraviolet B-irradiated damage in human keratinocytes.
abstract: The aim of this study was to investigate the cytoprotective properties of the ethyl acetate fraction of Sargassum muticum (SME) against ultraviolet B (UVB)-induced cell damage in human keratinocytes (HaCaT cells). SME exhibited scavenging activity toward the 1,1-diphenyl-2-picrylhydrazyl radicals and hydrogen peroxide (H(2)O(2)) and UVB-induced intracellular reactive oxygen species (ROS). SME also scavenged the hydroxyl radicals generated by the Fenton reaction (FeSO(4) + H(2)O(2)), which was detected using electron spin resonance spectrometry. In addition, SME decreased the level of lipid peroxidation that was increased by UVB radiation, and restored the level of protein expression and the activities of antioxidant enzymes that were decreased by UVB radiation. Furthermore, SME reduced UVB-induced apoptosis as shown by decreased DNA fragmentation and numbers of apoptotic bodies. These results suggest that SME protects human keratinocytes against UVB-induced oxidative stress by enhancing antioxidant activity in cells, thereby inhibiting apoptosis.
authors.affiliation: School of Medicine, Jeju National University, Jeju 690-756, South Korea; E-Mails:  mjpiao@hanmail.net  (M.J.P.);  pharmkhk@jejunu.ac.kr  (H.K.K.);  eunsyoo@jejunu.ac.kr  (E.S.Y.);  yskoh7@jejunu.ac.kr  (Y.S.K.).
authors.forename: Mei Jing
authors.initials: MJ
authors.lastname: Piao
authors.forename: Weon Jong
authors.initials: WJ
authors.lastname: Yoon
authors.forename: Hee Kyoung
authors.initials: HK
authors.lastname: Kang
authors.forename: Eun Sook
authors.initials: ES
authors.lastname: Yoo
authors.forename: Young Sang
authors.initials: YS
authors.lastname: Koh
authors.forename: Dong Sam
authors.initials: DS
authors.lastname: Kim
authors.forename: Nam Ho
authors.initials: NH
authors.lastname: Lee
authors.forename: Jin Won
authors.initials: JW
authors.lastname: Hyun
mesh_terms: D000085:Acetates; D000975:Antioxidants / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects; D001713:Biphenyl Compounds / Q000378:metabolism; D002374:Catalase / Q000378:metabolism; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D053938:DNA Fragmentation / Q000187:drug effects; D006801:Humans; D006861:Hydrogen Peroxide / Q000378:metabolism; D015603:Keratinocytes / Q000187:drug effects* / Q000528:radiation effects*; D015227:Lipid Peroxidation / Q000187:drug effects; D018384:Oxidative Stress / Q000187:drug effects; D010851:Picrates / Q000378:metabolism; D010936:Plant Extracts / Q000494:pharmacology*; D011837:Radiation-Protective Agents / Q000494:pharmacology*; D017382:Reactive Oxygen Species / Q000378:metabolism; D044647:Sargassum / Q000737:chemistry*; D013482:Superoxide Dismutase / Q000378:metabolism; D014466:Ultraviolet Rays / Q000009:adverse effects*
chemical_list: D000085:Acetates; D000975:Antioxidants; D001713:Biphenyl Compounds; D010851:Picrates; D010936:Plant Extracts; D011837:Radiation-Protective Agents; D017382:Reactive Oxygen Species; C007650:ethyl acetate; D006861:Hydrogen Peroxide; C004931:1,1-diphenyl-2-picrylhydrazyl; D002374:Catalase; D013482:Superoxide Dismutase