Physiological levels of tea catechins increase cellular lipid antioxidant activity of vitamin C and vitamin E in human intestinal Caco-2 cells
Physiological levels of tea catechins increase cellular lipid antioxidant activity of vitamin C and vitamin E in human intestinal Caco-2 cells
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DOI：
10.1016/j.cbi.2007.05.007
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发表时间：
2007-08-30
影响因子：
5.1
通讯作者：
Kuo, Shiu-Ming
中科院分区：
文献类型：
--
作者：
Intra, Janjira;Kuo, Shiu-Ming
氧化应激与各种慢性疾病的发展有关。含有多酚的蔬菜和水果被证明具有保护作用。 (-)-表没食子儿茶素-3-没食子酸酯 (EGCG) 是茶叶中富含的一种多酚，已被证明在无细胞条件下具有抗氧化活性，本研究重点关注细胞 EGCG 的作用。使用肠细胞模型来检查羟自由基诱导的氧化应激，我们在此报告生理浓度（0.1-1μM）的EGCG具有剂量和孵育时间依赖性细胞相关的脂质抗氧化活性（测量丙二醛的产生）。 10-40 μM 的维生素 E 和维生素 C 在较短的孵育时间下也显示出细胞相关的脂质抗氧化活性。当 EGCG 与维生素 E 或 C 一起孵育时，比单独添加维生素时始终观察到更多的抗氧化活性。 1 μM 的儿茶素（广泛存在于水果和蔬菜中）还可以显着提高维生素 E 和 C 的抗氧化活性。之前检查 EGCG 细胞相关活性的研究主要集中在 10-100 μM 的浓度范围。我们的结果表明，尽管膳食儿茶素的生理水平（0.1-1μM）远低于维生素，但即使在维生素存在下，它们也进一步有助于总抗氧化能力。 (c) 2007 Elsevier Ireland Ltd. 保留所有权利。
Oxidative stress has been linked to the development of various chronic diseases. Vegetables and fruits, which contain polyphenols, were shown to have protective effects. (-)-Epigallocatechin-3-gallate (EGCG), a polyphenol abundant in tea, has been shown to have antioxidant activities in cell-free conditions and this study focused on the effect of cellular EGCG. Using an intestinal cell model to examine the oxidative stress induced by hydroxyl radicals, we report here that physiological concentrations (0.1-1 mu M) of EGCG have dose- and incubation duration-dependent cell-associated lipid antioxidant activity (measuring malondialclehyde production). Vitamin E and vitamin C at 10-40 mu M also showed cell-associated lipid antioxidant activities under shorter incubation durations. When EGCG was included in the incubation with vitamin E or C, more antioxidant activities were consistently observed than when vitamins were added alone. Catechin (widely present in fruits and vegetables) at 1 mu M also significantly increased the antioxidant activity of vitamins E and C. Previous studies examining cell-associated activity of EGCG mainly focused on the 10-100 mu M concentration range. Our results suggest that although the physiological level (0.1-1 mu M) of dietary catechins is much lower than that of vitamins, they further contribute to the total antioxidant capacity even in the presence of vitamins. (c) 2007 Elsevier Ireland Ltd. All rights reserved.