Silencing of Id2 attenuates hypoxia/ischemia-induced neuronal injury via inhibition of neuronal apoptosis
Silencing of Id2 attenuates hypoxia/ischemia-induced neuronal injury via inhibition of neuronal apoptosis
复制标题
Id2 沉默通过抑制神经元凋亡减轻缺氧/缺血引起的神经元损伤
DOI：
10.1016/j.bbr.2015.07.018
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发表时间：
2015-10-01
影响因子：
2.7
通讯作者：
Qiu, Yongming
中科院分区：
文献类型：
--
作者：
Guo, Liemei;Yang, Xi;Qiu, Yongming
长期以来，缺血性卒中一直被认为是一种流行和严重的神经系统疾病，与高死亡率和高发病率有关。然而，目前的治疗方案仍然不是最优的，卒中的主要机制迫切需要。DNA结合/分化抑制因子2(Id2)在缺氧/缺血(H/I)后神经细胞中表达上调。本研究旨在探讨体外和体内神经细胞Id2基因敲除是否能保护神经细胞免受缺氧和缺血损伤。应用流式细胞术分析CoCl2处理的神经母细胞瘤B35细胞的神经细胞凋亡。在体内，通过单次侧脑室注射Cy3标记和胆固醇修饰的Id2-siRNA，在SpragueDawley大鼠身上实现了Id2基因的敲除。我们发现，在体外，Id2基因的敲除可减轻H/I诱导的神经细胞凋亡，而过表达Id2基因则产生相反的作用。在大鼠大脑中动脉闭塞(MCAO)模型中，Id2基因的体内敲除可显著改善神经功能缺失，缩小缺血脑梗塞体积，减少半影区神经元的凋亡。双重免疫荧光染色显示视网膜母细胞瘤肿瘤抑制蛋白(Rb)-Id2的共定位较少，而Rb-E2F1在半影区的共定位较多。细胞周期分析进一步证明Id2基因敲除诱导CoCl2处理的B35细胞G0/G1期停滞。本研究结果支持Id2在H/I诱导的神经细胞凋亡的调控中的作用，并可能通过抑制Id2的表达来保护脑组织免受缺血性损伤。(C)2015爱思唯尔B.V.保留所有权利。
Cerebral ischemic stroke has long been recognized as a prevalent and serious neurological disease that was associated with high mortality and morbidity. However, the current therapeutic protocols remain suboptimal with major mechanisms underlying stroke urgently warranted. Inhibitor of DNA binding/differentiation 2 (Id2) is found to be up-regulated in neuronal cells following hypoxia/ischemia (H/I). This study was aimed to investigate whether knockdown of Id2 in neuronal cells could protect them from hypoxic and ischemic injury both in vitro and in vivo. Flow cytometric analysis was employed to assess neuronal apoptosis in CoCl2-treated neuroblastoma B35 cells engineered to overexpress or knockdown Id2 expression. In vivo knockdown of Id2 was performed in Sprague-Dawley rats by a single intracerebroventricular injection of Cy3-labeled and cholesterol-modified Id2-siRNA. We found that knockdown of Id2 attenuated H/I-induced neuronal apoptosis in vitro while overexpression of Id2 produced an opposite effect. In a rat model of middle cerebral artery occlusion (MCAO), in vivo knockdown of Id2 significantly improved neurological deficits, reduced the volume of ischemic infarction and diminished the neuronal apoptosis in the penumbra area. Double immunofluorescence staining showed less co-localization of retinoblastoma tumor suppressor protein (Rb)-Id2 but greater co-localization of Rb-E2F1 in the penumbra area. Cell cycle assay further demonstrated that Id2 knockdown induced G0/G1 cell cycle arrest in CoCl2-treated B35 cells. The present data support the implication of Id2 in the modulation of H/I-induced neuronal apoptosis and may provide a potential therapeutic option to protect brain tissues from ischemic injury by inhibition of its expression. (C) 2015 Elsevier B.V. All rights reserved.