Wu Ming-Jiuan, Yen Jui-Hung, Wang Lisu, Weng Ching-Yi
Department of Biotechnology, Chia-Nan University of Pharmacy and Science, Tainan, Taiwan 717.
Am J Chin Med. 2004;32(5):681-93. doi: 10.1142/S0192415X04002387.
The stem and root of Porcelainberry (Ampelopsis brevipedunculata (Maxim.) Trautv.) (AB) was traditionally used as an anti-inflammatory, diuretic and anti-hepatotoxic agent in folk medicine. In this study, cell-free and cell culture systems were employed to investigate the antioxidant activity of the methanol extract of AB (MEAB). The cell-free system showed that the MEAB exhibited dose-dependent antioxidant activities against linoleic acid peroxidation and plasmid DNA oxidation. We also demonstrated that the MEAB possessed strong reducing power and scavenging effects of hydroxyl radicals and DPPH free radicals. The harmful effects of reactive oxygen metabolites on HepG2 cells and the possible antioxidant effects of the MEAB were also investigated. Pretreatment or cotreatment of HepG2 cells with the MEAB could significantly protect cells from H2O2-induced oxidative stress. This implies that the antioxidant effects in cell culture may result from the direct interaction between the MEAB and exogenous oxidant sources, as these occur in cell free systems, as well as from the induction of cellular stress gene expression. The antioxidant activity of the MEAB may partially explain its anti-inflammatory and anti-hepatotoxic effects.
蛇葡萄（Ampelopsis brevipedunculata (Maxim.) Trautv.）（AB）的茎和根在传统民间医学中被用作抗炎、利尿和抗肝毒剂。在本研究中，采用无细胞和细胞培养系统来研究AB甲醇提取物（MEAB）的抗氧化活性。无细胞系统显示，MEAB对亚油酸过氧化和质粒DNA氧化表现出剂量依赖性抗氧化活性。我们还证明，MEAB具有较强的还原能力以及对羟基自由基和DPPH自由基的清除作用。还研究了活性氧代谢产物对HepG2细胞的有害影响以及MEAB可能的抗氧化作用。用MEAB预处理或共处理HepG2细胞可显著保护细胞免受H2O2诱导的氧化应激。这意味着细胞培养中的抗氧化作用可能源于MEAB与外源性氧化源之间的直接相互作用（如在无细胞系统中发生的那样），以及细胞应激基因表达的诱导。MEAB的抗氧化活性可能部分解释了其抗炎和抗肝毒作用。
