EGCG inhibit chemical reactivity of iron through forming an Ngal-EGCG-iron complex.
EGCG inhibit chemical reactivity of iron through forming an Ngal-EGCG-iron complex.
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DOI：
10.1007/s10534-013-9681-8
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发表时间：
2013-12
期刊：
影响因子：
--
通讯作者：
Barasch J
中科院分区：
文献类型：
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作者：
Bao GH;Xu J;Hu FL;Wan XC;Deng SX;Barasch J
大量的证据表明，在芬顿和Haber-Weiss反应中，铁离子通过与活性氧相互作用，实现三价铁离子（Fe 3+）和亚铁离子（Fe 2+）之间的相互转化，从而生理上影响氧化还原循环。铁和ROS的失衡最终可能导致组织损伤，如肾近端小管损伤和坏死。许多方法被用来改善氧化应激引起的不平衡。（−）-表没食子儿茶素-3-没食子酸酯是茶叶中最活跃和最丰富的儿茶素，被发现参与保护氧化应激引起的一系列肾损伤。大多数研究表明，表没食子儿茶素没食子酸酯具有抗氧化作用。本文通过对茶叶提取物的LC-MS数据的多变量分析和结合试验表明，茶多酚EGCG可以通过蛋白质Ngal（急性肾损伤的生物标志物）与铁形成稳定的复合物。UV-Vis和荧光光谱分析结果表明，Ngal通过与EGCG形成Ngal-EGCG-Fe复合物，抑制了铁与EGCG的化学反应。考虑到铁和ROS的相互作用，我们提出EGCG可能既作为抗氧化剂又作为Ngal结合铁载体在保护肾脏免受损伤中起作用。
Accumulated evidence indicates that the interconversion of iron between ferric (Fe3+) and ferrous (Fe2+) can be realized through interaction with reactive oxygen species in the Fenton and Haber–Weiss reactions and thereby physiologically effects redox cycling. The imbalance of iron and ROS may eventually cause tissue damage such as renal proximal tubule injury and necrosis. Many approaches were exploited to ameliorate the oxidative stress caused by the imbalance. (−)-Epigallocatechin-3-gallate, the most active and most abundant catechin in tea, was found to be involved in the protection of a spectrum of renal injuries caused by oxidative stress. Most of studies suggested that EGCG works as an antioxidant. In this paper, Multivariate analysis of the LC–MS data of tea extracts and binding assays showed that the tea polyphenol EGCG can form stable complex with iron through the protein Ngal, a biomarker of acute kidney injury. UV–Vis and Luminescence spectrum methods showed that Ngal can inhibit the chemical reactivity of iron and EGCG through forming an Ngal–EGCG–iron complex. In thinking of the interaction of iron and ROS, we proposed that EGCG may work as both antioxidant and Ngal binding siderphore in protection of kidney from injuries.