title: Black soybean seed coat polyphenols prevent AAPH-induced oxidative DNA-damage in HepG2 cells.
abstract: Black soybean seed coat extract (BE), which contains abundant polyphenols such as procyanidins, cyanidin 3-glucoside, (+)-catechin, and (-)-epicatechin, has been reported on health beneficial functions such as antioxidant activity, anti-inflammatory, anti-obesity, and anti-diabetic activities. In this study, we investigated that prevention of BE and its polyphenols on 2,2'-azobis(2-methylpropionamide) dihydrochloride (AAPH)-induced oxidative DNA damage, and found that these polyphenols inhibited AAPH-induced formation of 8-hydroxy-2'-deoxyguanosine (8-OHdG) as a biomarker for oxidative DNA damage in HepG2 cells. Under the same conditions, these polyphenols also inhibited AAPH-induced accumulation of reactive oxygen species (ROS) in the cells. Inhibition of ROS accumulation was observed in both cytosol and nucleus. It was confirmed that these polyphenols inhibited formation of AAPH radical using oxygen radical absorbance capacity assay under the cell-free conditions. These results indicate that polyphenols in BE inhibit free radical-induced oxidative DNA damages by their potent antioxidant activity. Thus, BE is an effective food material for prevention of oxidative stress and oxidative DNA damages.
authors.affiliation: Organization of Advanced Science and Technology, Kobe University, Kobe, Hyogo 657-8501, Japan.
authors.forename: Yasukiyo
authors.initials: Y
authors.lastname: Yoshioka
authors.affiliation: Graduate School of Agricultural Science, Kobe University, Kobe, Hyogo 657-8501, Japan.
authors.forename: Xiu
authors.initials: X
authors.lastname: Li
authors.affiliation: Graduate School of Agricultural Science, Kobe University, Kobe, Hyogo 657-8501, Japan.
authors.forename: Tianshun
authors.initials: T
authors.lastname: Zhang
authors.affiliation: Organization of Advanced Science and Technology, Kobe University, Kobe, Hyogo 657-8501, Japan; Graduate School of Agricultural Science, Kobe University, Kobe, Hyogo 657-8501, Japan.
authors.forename: Takakazu
authors.initials: T
authors.lastname: Mitani
authors.affiliation: Organization of Advanced Science and Technology, Kobe University, Kobe, Hyogo 657-8501, Japan.
authors.forename: Michiko
authors.initials: M
authors.lastname: Yasuda
authors.affiliation: Research & Development Department, Fujicco Co., Ltd., Kobe, Hyogo 650-8558, Japan.
authors.forename: Fumio
authors.initials: F
authors.lastname: Nanba
authors.affiliation: Research & Development Department, Fujicco Co., Ltd., Kobe, Hyogo 650-8558, Japan.
authors.forename: Toshiya
authors.initials: T
authors.lastname: Toda
authors.affiliation: Graduate School of Agricultural Science, Kobe University, Kobe, Hyogo 657-8501, Japan.
authors.forename: Yoko
authors.initials: Y
authors.lastname: Yamashita
authors.affiliation: Organization of Advanced Science and Technology, Kobe University, Kobe, Hyogo 657-8501, Japan; Graduate School of Agricultural Science, Kobe University, Kobe, Hyogo 657-8501, Japan.
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Ashida
keywords: 8-OHdG; LC-MS/MS; ROS; hepatocytes; procyanidin