Ebselen attenuates cisplatin-induced ROS generation through Nrf2 activation in auditory cells
Ebselen attenuates cisplatin-induced ROS generation through Nrf2 activation in auditory cells
复制标题
DOI：
10.1016/j.heares.2009.03.003
复制
发表时间：
2009-05-01
期刊：
影响因子：
2.8
通讯作者：
Park, Raekil
中科院分区：
文献类型：
--
作者：
Kim, Se-Jin;Park, Channy;Park, Raekil
Ebselen是一种有机硒化合物，作为谷胱甘肽过氧化物酶模拟物，已被证明具有抗氧化和抗炎活性。然而，这种效应背后的分子机制在听觉细胞中并不完全清楚。本研究的目的是探讨依布硒啉对顺铂诱导的HEI-OC 1听觉细胞毒性的保护作用，从出生后两天的大鼠（P-2）和成年Balb/C小鼠耳蜗外植体的器官型培养。依布硒啉预处理可改善顺铂诱导的HEI-OC 1细胞和Corti器官型培养物的凋亡。依布硒啉预处理也显着抑制顺铂诱导的细胞内活性氧（ROS），细胞内活性氮（RNS）和脂质过氧化水平的增加。依布硒啉剂量依赖性地增加抗氧化反应元件（ARE）-荧光素酶报告基因在HEI-OC 1细胞中的表达水平，通过易位的Nrf 2到细胞核。此外，我们发现，预处理与依布硒啉显着恢复Nrf 2的功能，而它改善了顺铂的细胞毒性与pcDNA3.1（对照）或DN-Nrf 2（显性阴性）质粒转染细胞。我们还观察到依布硒啉激活Nrf 2增加了II相抗氧化基因的表达，包括血红素加氧酶（HO-1）、NAD（P）H：奎宁氧化还原酶和γ-谷氨酰半胱氨酸合成酶（γ-GCS）。依布硒啉处理导致耳蜗毛细胞HO-1和核内Nrf 2的表达增加。Balb/C小鼠腹腔注射顺铂后，于第8天测定听性脑干反应（ABR）阈值。顺铂组（16 mg/kg，n = 5;短声和8 kHz刺激，P < 0.05; 4、16和32 kHz刺激，P < 0.01）ABR阈值明显偏移，而顺铂和依布硒啉组无明显变化。这些结果表明，依布硒啉激活Nrf 2-ARE信号通路，最终防止顺铂的自由基应激，并进一步有助于保护听觉感觉毛细胞免受顺铂产生的自由基的影响。(C)2009爱思唯尔有限公司版权所有。
Ebselen, an organoselenium compound that acts as a glutathione peroxidase mimetic, has been demonstrated to possess antioxidant and anti-inflammatory activities. However, the molecular mechanism underlying this effect is not fully understood in auditory cells. The purpose of the present study is to investigate the protective effect of ebselen against cisplatin-induced toxicity in HEI-OC1 auditory cells, organotypic cultures of cochlear explants from two-day postnatal rats (P-2) and adult Balb/C mice. Pretreatment with ebselen ameliorated apoptotic death induced by cisplatin in HEI-OC1 cells and organotypic cultures of Corti's organ. Ebselen pretreatment also significantly suppressed cisplatin-induced increases in intracellular reactive oxygen species (ROS), intracellular reactive nitrogen species (RNS) and lipid peroxidation levels. Ebselen dose-dependently increased the expression level of an antioxidant response element (ARE)-luciferase reporter in HEI-OC1 cells through the translocation of Nrf2 into the nucleus. Furthermore, we found that pretreatment with ebselen significantly restored Nrf2 function, whereas it ameliorated the cytotoxicity of cisplatin in cells transfectants with either a pcDNA3.1 (control) or a DN-Nrf2 (dominant-negative) plasmid. We also observed that Nrf2 activation by ebselen increased the expression of phase II antioxidant genes, including heme oxygenase (HO-1), NAD(P)H:quinine oxidoreductase, and gamma-glutamylcysteine synthetase (gamma-GCS). Treatment with ebselen resulted in an increased expression of HO-I and intranuclear Nrf2 in hair cells of organotypic cultured cochlea. After intraperitoneal injection with cisplatin, auditory brainstem responses (ABRs) threshold was measured on 8th day in Balb/C mice. ABR threshold shift was marked occurred in mice injected with cisplatin (16 mg/kg, n = 5; Click and 8-kHz stimuli, P < 0.05; 4, 16 and 32 kHz, p < 0.01), whereas that of animal group which was treated with cisplatin and ebselen was not significantly changed. These results suggest that ebselen activates the Nrf2-ARE signaling pathway, which ultimately prevents free radical stresses from cisplatin and further contributes to protect auditory sensory hair cells from free radicals produced by cisplatin. (C) 2009 Elsevier B.V. All rights reserved.