title: Protective Effects of Black Rice Extracts on Oxidative Stress Induced by tert-Butyl Hydroperoxide in HepG2 Cells.
abstract: Black rice contains many biologically active compounds. The aim of this study was to investigate the protective effects of black rice extracts (whole grain extract, WGE and rice bran extract, RBE) on tert-butyl hydroperoxide (TBHP)-induced oxidative injury in HepG2 cells. Cellular reactive oxygen species (ROS), antioxidant enzyme activities, malondialdehyde (MDA) and glutathione (GSH) concentrations were evaluated as biomarkers of cellular oxidative status. Cells pretreated with 50 and 100 μg/mL of WGE or RBE were more resistant to oxidative stress in a dose-dependent manner. The highest WGE and BRE concentrations enhanced GSH concentrations and modulated antioxidant enzyme activities (glutathione reductase, glutathione-S-transferase, catalase, and superoxide dismutase) compared to TBHP-treated cells. Cells treated with RBE showed higher protective effect compared to cells treated with WGE against oxidative insult. Black rice extracts attenuated oxidative insult by inhibiting cellular ROS and MDA increase and by modulating antioxidant enzyme activities in HepG2 cells.
authors.affiliation: Department of Food Science and Biotechnology, Chungbuk National University, Chungbuk 361-763, Korea.
authors.forename: Seon-Mi
authors.initials: SM
authors.lastname: Lee
authors.affiliation: Functional Food & Nutrition Division, Department of AgroFood Resources, Rural Development Administration, Gyeonggi 441-857, Korea.
authors.forename: Youngmin
authors.initials: Y
authors.lastname: Choi
authors.affiliation: Department of Food Science and Biotechnology, Chungbuk National University, Chungbuk 361-763, Korea.
authors.forename: Jeehye
authors.initials: J
authors.lastname: Sung
authors.affiliation: Department of Food Science and Biotechnology, Chungbuk National University, Chungbuk 361-763, Korea.
authors.forename: Younghwa
authors.initials: Y
authors.lastname: Kim
authors.affiliation: Department of Food Science and Biotechnology, Chungbuk National University, Chungbuk 361-763, Korea.
authors.forename: Heon-Sang
authors.initials: HS
authors.lastname: Jeong
authors.affiliation: Department of Food Science and Biotechnology, Chungbuk National University, Chungbuk 361-763, Korea.
authors.forename: Junsoo
authors.initials: J
authors.lastname: Lee
keywords: HepG2 cell; antioxidant enzyme; black rice; glutathione; oxidative stress