Antioxidant tert-butylhydroquinone ameliorates arsenic-induced intracellular damages and apoptosis through induction of Nrf2-dependent antioxidant responses as well as stabilization of anti-apoptotic factor Bcl-2 in human keratinocytes
Antioxidant tert-butylhydroquinone ameliorates arsenic-induced intracellular damages and apoptosis through induction of Nrf2-dependent antioxidant responses as well as stabilization of anti-apoptotic factor Bcl-2 in human keratinocytes
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DOI：
10.1016/j.freeradbiomed.2016.02.009
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发表时间：
2016-05-01
影响因子：
7.4
通讯作者：
Li, Bing
中科院分区：
文献类型：
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作者：
Duan, Xiaoxu;Li, Jinlong;Li, Bing
人类皮肤是无机砷的已知靶点，其影响范围从角化过度到皮肤恶性肿瘤。叔丁基对苯二酚（tBHQ）是一种被批准的食品级酚类抗氧化剂，已被证明在多种细胞和组织中诱导显着的抗氧化活性。本研究旨在探讨tBHQ对砷诱导的角质形成细胞毒性和凋亡的保护作用。我们的研究结果表明，tBHQ拮抗砷诱导的细胞活力下降，活性氧（ROS）和脂质过氧化反应的产生，以及抗氧化酶超氧化物歧化酶（SOD）和过氧化氢酶（CAT）的活性降低。我们还发现tBHQ缓解了砷暴露引起的G2/M期阻滞，这与改变细胞周期调节因子cyclin D1和CDK 4的表达有关。tBHQ处理进一步减少砷诱导的细胞凋亡，这与线粒体膜电位（AV）去极化、细胞色素c从线粒体释放以及存活信号相关因子caspase 3激活的有效恢复同时发生。我们的实验随后证实tBHQ通过增加核和细胞质中的NRF 2蛋白以及上调NRF 2下游靶点NAD（P）H：奎宁氧化还原酶1（NQO 1）和血红素加氧酶-1（HO-1）来激活核因子E2相关因子2（NRF 2）通路。更有趣的是，砷诱导的抗凋亡因子B细胞淋巴瘤-2（Bcl-2）的减少和促凋亡因子Bcl-2相关X蛋白（Bax）的增加都可以被tBHQ预处理逆转。这些结果共同表明，tBHQ可以改善砷诱导的细胞毒性和细胞凋亡，这可能与诱导Nrf 2依赖的抗氧化反应以及稳定抗凋亡因子Bcl-2在人角质形成细胞。(C)2016 Elsevier Inc. All rights reserved.
Human skin is a known target site of inorganic arsenic with effects ranging from hyperkeratosis to dermal malignancies. Tert-butylhydroquinone (tBHQ), approved food-grade phenolic antioxidant, is demonstrated to induce remarkable antioxidant activity in a variety of cells and tissues. The present study aimed at the protective effects of tBHQ on arsenic-induced cytotoxicity and apoptosis in human keratinocytes. Our results demonstrated that tBHQ antagonized arsenic-induced decrease of cell viability, generation of reactive oxygen species (ROS) and lipid peroxidation, as well as reduction of antioxidative enzymes superoxide dismutase (SOD) and catalase (CAT) activities. We also found that tBHQ relieved the G2/M phase arrest by arsenic exposure, which was associated with altering the expression of cell cycle regulators cyclin D1 and CDK4. tBHQ treatment further reduced the numbers of arsenic-induced mitochondrial-mediated apoptotic cells, which occurred concomitantly with the effective recovery of mitochondrial membrane potential (AV,) depolarization, the release of cytochrome c releasing from the mitochondrial as well as the survival signal related factor caspase 3 activation. Our experiments then confirmed that tBHQ activated nuclear factor E2-related factor 2 (NRF2) pathway by increasing NRF2 protein in both nucleus and cytoplasm and upregulating NRF2 downstream targets NAD(P)H: quinine oxidoreductase 1 (NQO1) and heme oxygenase-1 (HO-1). More interestingly, arsenic-induced decrease of anti-apoptotic factor B-cell lymphoma-2 (Bcl-2) and increase of pro-apoptotic factor Bcl-2-associated X protein (Bax) could all be reversed by tBHQ pretreatment. These results suggested together that tBHQ could ameliorate arsenic-induced cytotoxicity and apoptosis, which might be linked with the induction of Nrf2-dependent antioxidant responses as well as stabilization of anti-apoptotic factor Bcl-2 in human keratinocytes. (C) 2016 Elsevier Inc. All rights reserved.