BRG1 expression is increased in thoracic aortic aneurysms and regulates proliferation and apoptosis of vascular smooth muscle cells through the long non-coding RNA HIF1A-AS1 in vitro
BRG1 expression is increased in thoracic aortic aneurysms and regulates proliferation and apoptosis of vascular smooth muscle cells through the long non-coding RNA HIF1A-AS1 in vitro
复制标题
BRG1在胸主动脉瘤中表达增加并在体外通过长非编码RNA HIF1A-AS1调节血管平滑肌细胞的增殖和凋亡
DOI：
10.1093/ejcts/ezu215
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发表时间：
2015-03-01
影响因子：
3.4
通讯作者：
Xu, Zhiyun
中科院分区：
文献类型：
--
作者：
Wang, Shuwei;Zhang, Xiwu;Xu, Zhiyun
Brahma-related gene 1（BRG 1）和长链非编码RNA（lncRNA）在细胞过程中起重要作用。然而，关于它们在胸主动脉瘤中的作用知之甚少。方法：采用实时定量PCR、免疫组化和western blot方法检测BRG 1 mRNA和蛋白在人胸主动脉瘤中的表达，以及BRG 1和lncRNA HIF 1 α-反义RNA 1对胸主动脉瘤平滑肌细胞增殖和凋亡的调控作用。慢病毒载体可上调BRG 1的表达。采用Cell Counting Kit-8和末端脱氧核苷酸转移酶dUTP缺口末端标记法研究血管平滑肌细胞增殖和凋亡。Western blot检测Caspase 3和Bcl 2蛋白表达。通过微阵列在BRG 1功能获得和丧失的血管平滑肌细胞中鉴定BRG 1调节的LncRNA。结果：BRG 1在胸主动脉瘤组织中的表达明显高于正常对照组（P < 0. 05），而在胸主动脉瘤组织中的表达明显低于正常对照组（P < 0. 05）。BRG 1在人主动脉平滑肌细胞中的过表达促进了细胞凋亡并降低了增殖。在BRG 1敲低和过表达的血管平滑肌细胞中，HIF 1 α-反义RNA 1的表达分别显著下调和上调。我们进一步证明了在血管平滑肌细胞中通过siRNA抑制HIF 1 α-反义RNA 1可减少凋亡并促进增殖。BRG 1在胸主动脉瘤的主动脉中膜中过表达，BRG 1和HIF 1 α-反义RNA 1之间的相互作用在体外血管平滑肌细胞的增殖和凋亡中起关键作用，这可能有助于胸主动脉瘤的发病机制。
OBJECTIVES: Brahma-related gene 1 (BRG1) and long non-coding RNAs (lncRNAs) play important roles in cellular processes. However, little is known regarding their roles in thoracic aortic aneurysms. We investigated BRG1 expression in thoracic aortic aneurysms and the roles of BRG1 and the lncRNA HIF 1 alpha-antisense RNA 1 in regulating the proliferation and apoptosis of aortic smooth muscle cells in vitro.METHODS: BRG1 mRNA and protein expression in human aortic media specimens were examined by quantitative real-time polymerase chain reaction, immunohistochemical staining and western blot. BRG1 expression was up-regulated by lentiviral vectors. Vascular smooth muscle cell proliferation and apoptosis were studied using Cell Counting Kit-8 and terminal deoxynucleotidyl transferase dUTP nick-end labelling assays. We performed western blots to detect Caspase3 and Bcl2 protein expression. LncRNAs regulated by BRG1 were identified through microarray in BRG1 gain-and loss-of-function vascular smooth muscle cells. Finally, the expression of HIF 1 alpha-antisense RNA 1 was reduced by siRNA and cell proliferation and apoptosis was studied using Cell Counting Kit-8 assays, caspase-3 activity assays and western blot.RESULTS: BRG1 expression in the aortic media was significantly higher in thoracic aortic aneurysms than in normal controls. Overexpression of BRG1 in human aortic smooth muscle cells promoted apoptosis and reduced proliferation. The expression of HIF 1 alpha-antisense RNA 1 was significantly down-and up-regulated in BRG1 knock-down and overexpressing vascular smooth muscle cells, respectively. We further demonstrated that suppression of HIF 1 alpha-antisense RNA 1 by siRNA in vascular smooth muscle cells reduced apoptosis and promoted proliferation.CONCLUSIONS: BRG1 is overexpressed in the aortic media of thoracic aortic aneurysms and the interaction between BRG1 and HIF 1 alpha-antisense RNA 1 plays a key role in the proliferation and apoptosis of vascular smooth muscle cells in vitro, which may contribute to the pathogenesis of thoracic aortic aneurysms.