The cap'n'collar transcription factor Nrf2 mediates both intrinsic resistance to environmental stressors and an adaptive response elicited by chemopreventive agents that determines susceptibility to electrophilic xenobiotics
The cap'n'collar transcription factor Nrf2 mediates both intrinsic resistance to environmental stressors and an adaptive response elicited by chemopreventive agents that determines susceptibility to electrophilic xenobiotics
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DOI：
10.1016/j.cbi.2010.09.025
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发表时间：
2011-06-30
影响因子：
5.1
通讯作者：
Hayes, John D.
中科院分区：
文献类型：
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作者：
Higgins, Larry G.;Hayes, John D.
转录因子Nrf 2调节编码药物代谢酶和药物转运蛋白的基因，以及参与谷胱甘肽、硫氧还蛋白和过氧化物氧还蛋白抗氧化途径的酶。使用来自Nrf 2（+/+）和Nrj 2（-/-）小鼠的小鼠胚胎成纤维细胞（MEF）细胞，结合3个（4，5-二甲基噻唑-2-基）-2，5-二苯基溴化四氮唑（MTT）细胞毒性测定，我们已经表明Nrf 2的缺失降低了突变成纤维细胞对异硫氰酸酯的内在抗性（即萝卜硫素）、环氧化物（即（2S，3S）-（-）-3-苯基缩水甘油、3-苯基缩水甘油酸乙酯和苯乙烯-7，8-环氧化物）、过氧化物、氢醌和醌（即叔丁基过氧化氢、叔丁基对苯二酚和2，3-二甲氧基萘醌）、NaAsO 2和各种诱变剂，包括β-丙内酯，顺铂、氮芥和甲磺酸甲酯的浓度降低至与在等效野生型细胞中观察到的浓度的50%相似。Nrf 2（+/+）成纤维细胞暴露于无毒剂量，而Nrf 2（-/-）成纤维细胞未暴露于无毒剂量（3 μ mol/l）的化学预防剂萝卜硫素（Sul）刺激适应性反应，在第一次接触异硫氰酸酯后18小时，引起谷氨酸-半胱氨酸连接酶催化亚基（Gclc）和修饰亚基（Gclm）mRNA水平的2- 10倍诱导，谷胱甘肽S-转移酶和NAD（P）H：醌氧化还原酶-1（Nqo 1）;这伴随着总谷胱甘肽增加1.5- 1.9倍。在用外源性物质攻击之前，用3 μ M Sul预处理Nrf 2（+/+）MEF细胞18小时，赋予了2.0- 4.0倍的抗异硫氰酸酯、活性羰基、过氧化物、醌类的保护。NaAsO 2，和抗癌氮芥苯丁酸氮芥，但预处理3 μ M的Sul在Nrf 2（-/-）MEF细胞中没有产生这样的耐受性增加。对丙烯醛，氢过氧化枯烯和苯丁酸氮芥，预处理野生型成纤维细胞与3 μ M的Sul产生的诱导性耐药，是依赖于谷胱甘肽，因为同时预处理与5 μ mol/1丁硫氨酸亚砜废除这些外源性物质的耐受性增加。然而，对甲萘醌的诱导耐药性发生在3 μ M Sul预处理是独立的谷胱甘肽，可能是由于上调Nqo 1。因此，Nrf 2控制细胞对亲电体的抗性。(C)2010年由Elsevier爱尔兰有限公司出版。
Transcription factor Nrf2 regulates genes encoding drug-metabolising enzymes and drug transporters, as well as enzymes involved in the glutathione, thioredoxin and peroxiredoxin antioxidant pathways. Using mouse embryonic fibroblast (MEF) cells from Nrf2(+/+) and Nrj2(-/-) mice, in conjunction with the 3(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) cytotoxicity assay, we have shown that loss of Nrf2 diminishes the intrinsic resistance of mutant fibroblasts towards isothiocyanates (i.e. sulforaphane), epoxides (i.e. (2S,3S)-(-)-3-phenylglycidol, ethyl 3-phenylglycidate and styrene-7,8-epoxide), peroxides, hydroquinones and quinones (i.e. tert-butylhydroperoxide, tert-butylhydroquinone and 2,3-dimethoxynaphthoquinone), NaAsO2, and various mutagens, including beta-propiolactone, cisplatin, mechlorethamine and methyl methanesulfonate to similar to 50% of that observed in equivalent wild-type cells. Exposure of Nrf2(+/+) fibroblasts, but not Nrj2(-/-) fibroblasts, to a non-toxic dose (3 mu mol/1) of the chemopreventive agent sulforaphane (Sul) stimulated an adaptive response that, 18 h after first being subjected to the isothiocyanate, caused an induction of between 2- and 10-fold in the levels of mRNA for glutamate-cysteine ligase catalytic (Gclc) and modifier (Gclm) subunits, glutathione S-transferases and NAD(P)H:quinone oxidoreductase-1 (Nqo1); this was accompanied by an increase in total glutathione of between 1.5- and 1.9-fold. Pre-treatment of Nrf2(+/+) MEF cells with 3 mu M Sul for 18 h prior to challenge with xenobiotics, conferred between 2.0- and 4.0-fold protection against isothiocyanates, reactive carbonyls, peroxides, quinones. NaAsO2, and the anticancer nitrogen mustard chlorambucil, but pre-treatment with 3 mu M Sul produced no such increased tolerance in Nrf2(-/-) MEF cells. The inducible resistance towards acrolein, cumene hydroperoxide and chlorambucil, produced by pre-treating wild-type fibroblasts with 3 mu M Sul, was dependent on glutathione because simultaneous pre-treatment with 5 mu mol/1 buthionine sulfoximine abolished the increased tolerance of these xenobiotics. However, inducible resistance towards menadione that occurred upon pre-treatment with 3 mu M Sul was independent of glutathione and may be due to upregulation of Nqo1. Thus Nrf2 controls cellular resistance against electrophiles. (C) 2010 Published by Elsevier Ireland Ltd.