Inhibition of Siah2 ubiquitin ligase ameliorates monocrotaline-induced pulmonary arterial remodeling through inactivation of YAP
Inhibition of Siah2 ubiquitin ligase ameliorates monocrotaline-induced pulmonary arterial remodeling through inactivation of YAP
复制标题
Siah2 泛素连接酶的抑制可通过 YAP 失活改善野百合碱诱导的肺动脉重塑
DOI：
10.1016/j.lfs.2019.117159
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发表时间：
2020-02-01
期刊：
影响因子：
6.1
通讯作者：
Li, Manxiang
中科院分区：
文献类型：
--
作者：
Wang, Qingting;Shi, Wenhua;Li, Manxiang
目的：研究表明E3泛素连接酶7-缺失同源物2（Siah 2）的上调和Hippo信号通路效应子相关蛋白（雅普）的激活参与了肺动脉高压（PAH）的发生发展。但Siah 2在野百合碱（monocrotaline，MCT）诱导的PAH大鼠模型中是否激活雅普尚不清楚。通过右室收缩压（RVSP）、右室肥厚指数（RVHI）、中膜厚度百分比（%MT）、α-SMA、Ki-67和TUNEL染色评价PAH的发生发展。使用免疫印迹法检查Siah 2、Lats 1/2、雅普磷酸化和总雅普的蛋白水平以及雅普的亚细胞定位。主要发现：在MCT诱导的PAH大鼠中，Siah 2蛋白水平显著升高，伴随着Lats 1/2的蛋白酶体依赖性降解以及随后的雅普的上调和去磷酸化及其核定位。给予PAH大鼠Siah 2抑制剂Vitamin K3或蛋白酶体抑制剂MG-132可显著抑制MCT诱导的Lats 1/2下调和雅普激活，最终降低PAH大鼠RVSP、RVHI、%MT、肺动脉肌化、肺动脉平滑肌细胞（PASMCs）增殖并增强PASMCs凋亡。Siah 2通过使Lats 1/2失稳并随后刺激雅普活化，促进MCT诱导的PAH的发展。抑制Siah 2或蛋白酶体可通过灭活雅普来改善肺动脉重构，提示Siah 2泛素连接酶作为一个新的靶点可能在PAH的治疗中具有潜在的价值。
Aims: It has been shown that up-regulation of E3 ubiquitin ligase seven-in-absentia-homolog 2 (Siah2) and activation of Hippo signaling pathway effector yes-associated protein (YAP) are involved in the development of pulmonary arterial hypertension (PAH). However, it is still unclear whether Siah2 activates YAP in monocrotaline (MCT)-induced PAH rat models.Main methods: Intraperitoneal injection of MCT was used to induce PAH rat models. The right ventricular systolic pressure (RVSP), right ventricle hypertrophy index (RVHI), percentage of medial wall thickness (%MT), alpha-SMA, Ki-67 and TUNEL staining were performed to evaluate the development of PAH. Protein levels of Siah2, Lats1/2, YAP phosphorylation and total YAP, and the subcellular localization of YAP were examined using immunoblotting. Proteasome activity was measured by an assay kit.Key findings: The protein level of Siah2 was significantly increased in MCT-induced PAH rats, this was accompanied with the proteasome-dependent degradation of Lats1/2 and subsequent up-regulation and dephosphorylation of YAP and its nuclear localization. Administration of PAH rats with Siah2 inhibitor Vitamin K3 or proteasome inhibitor MG-132 dramatically suppressed MCT-induced down-regulation of Lats1/2 and activation of YAP, finally reduced RVSP, RVHI, %MT, pulmonary arterial muscularization, pulmonary arterial smooth muscle cells (PASMCs) proliferation and enhanced PASMCs apoptosis in PAH rats.Significance: Siah2 contributes to the development of MCT-induced PAH by destabilizing Lats1/2 and subsequently stimulating YAP activation. Inhibition of Siah2 or proteasome alleviates pulmonary arterial remodeling through inactivation of YAP, indicating Siah2 ubiquitin ligase as a novel target might have potential value in the management of PAH.