title: Identification of 5-hydroxy-3,6,7,8,3´,4´-hexamethoxyflavone from Hizikia fusiforme involved in the induction of the apoptosis mediators in human AGS carcinoma cells.
abstract: An 80% ethanol extract of Hizikia fusiforme was obtained and followed by successive fractionation using the organic solvents n-hexane, ethyl acetate, and n-butanol to identify the antioxidative substance. The aqueous part of the nbutanol fractionation step, showing high antioxidative activity, was subjected to reverse-phase liquid chromatography. As a result, a substance purified from a BB-2 fraction showed high antioxidative activity. The m/z 419 [M+H] molecular ion peak in the fraction was observed by the analysis of the ESI-LC/MS spectrum. By the analysis of 1H NMR (500 MHz, DMSO-d6) and 13C NMR (125 MHz, DMSO-d6) spectra, a unique compound of the fraction was biochemically identified as a 5-hydroxy-3,6,7,8,3´,4´- hexamethoxyflavone (5HHMF). We also investigated the effect of 5HHMF on human gastric AGS carcinoma cells. Western blot analysis suggested that the flavone substantially increased the levels of the death receptor-associated apoptosis mediators Fas, Fas L, FADD, TRADD, and DR4 in a concentration-dependent manner. The levels of Fas, Fas L, TRADD, and DR4 in the cells treated with 5HHMF (5 microgram/ml) were approximately 26.4-, 12.8-, 6.7-, and 9.8- times higher than those of non-treated cells, respectively. Of note, the level of FADD protein in the cells exposed to 5HHMF (1 microgram/ml) increased approximately 9.6-times. In addition, the cleavage of caspase-3, -8, and -9 in cultured AGS cells treated with 5HHMF was significantly confirmed. Therefore, our results suggest that 5HHMF from H. fusiforme is involved in the induction of death receptor-associated apoptosis mediators in human gastric AGS carcinoma cells.
authors.affiliation: Department of Biotechnology, Dong-A University, Busan, Korea.
authors.forename: Min Jeong
authors.initials: MJ
authors.lastname: Kim
authors.forename: Hye Hyeon
authors.initials: HH
authors.lastname: Lee
authors.forename: Min Jeong
authors.initials: MJ
authors.lastname: Seo
authors.forename: Byoung Won
authors.initials: BW
authors.lastname: Kang
authors.forename: Jeong Uck
authors.initials: JU
authors.lastname: Park
authors.forename: Kyoung-Sook
authors.initials: KS
authors.lastname: Kim
authors.forename: Gi-Young
authors.initials: GY
authors.lastname: Kim
authors.forename: Woo Hong
authors.initials: WH
authors.lastname: Joo
authors.forename: Yung Hyun
authors.initials: YH
authors.lastname: Choi
authors.forename: Young-Su
authors.initials: YS
authors.lastname: Cho
authors.forename: Yong Kee
authors.initials: YK
authors.lastname: Jeong
mesh_terms: D017209:Apoptosis / Q000187:drug effects*; D015153:Blotting, Western; D020169:Caspases / Q000378:metabolism; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D053418:Death Domain Receptor Signaling Adaptor Proteins / Q000378:metabolism; D047309:Flavones / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D006801:Humans; D000459:Phaeophyceae / Q000737:chemistry*; D010936:Plant Extracts / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D017382:Reactive Oxygen Species / Q000378:metabolism; D013274:Stomach Neoplasms / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology
chemical_list: D053418:Death Domain Receptor Signaling Adaptor Proteins; D047309:Flavones; D010936:Plant Extracts; D017382:Reactive Oxygen Species; C521815:5-hydroxy-3,6,7,8,3',4'-hexamethoxyflavone; D020169:Caspases