Spironolactone suppresses aldosterone-induced Kv1.5 expression by attenuating mineralocorticoid receptor-Nox1/2/4-mediated ROS generation in neonatal rat atrial myocytes
Spironolactone suppresses aldosterone-induced Kv1.5 expression by attenuating mineralocorticoid receptor-Nox1/2/4-mediated ROS generation in neonatal rat atrial myocytes
复制标题
螺内酯通过减弱新生大鼠心房肌细胞中盐皮质激素受体 Nox1/2/4 介导的 ROS 生成来抑制醛固酮诱导的 Kv1.5 表达
DOI：
10.1016/j.bbrc.2019.10.039
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发表时间：
2019-12-03
影响因子：
3.1
通讯作者：
Gao, Xiuren
中科院分区：
文献类型：
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作者：
Lu, Guihua;Li, Jie;Gao, Xiuren
我们先前的研究表明，血管紧张素II(Ang II)通过激活依赖于ROS的Smad2/3(形成P-Smad2/3)和ERK1/2(形成P-ERK1/2)，增强Kv1.5的表达，Kv1.5是一个有希望治疗心房颤动(AF)的靶点。最近的一项研究表明，醛固酮(aldosterone，ALDO)上调大鼠房颤模型的心房Kv1.5蛋白，但其机制尚不清楚。本研究旨在阐明Aldo诱导Kv1.5表达的机制，并检测螺内酯对心房Kv1.5的调节作用。我们的Western印迹分析表明，Aldo/minalocorticoid受体(MR)与Ang II/AT(1)R相互作用，上调培养的新生心房肌细胞(NRAMs)Kv1.5的表达。用安体舒通阻断MR和用氯沙坦阻断AT(1)R可显著抑制Aldo和Ang II联合作用对Kv1.5表达的诱导。Aldo可增加NOX1、NOX2和NOX4的蛋白表达，但这种作用可被螺内酯预处理所消除。Aldo诱导的Kv1.5上调也可被Src蛋白酪氨酸激酶家族抑制剂PP2、NOX2抑制剂gp9lds-Tat和NoXL/NOX4抑制剂GKT137831逆转，但不能被Rac GTP酶抑制剂NSC23766逆转。流式细胞仪检测结果显示，螺内酯、PP2、gp9lds-Tat和GKT137831均能抑制Aldo诱导的ROS生成。螺内酯可抑制Aldo诱导的磷酸化Src(P-Src)、P-Smad2/3和P-ERK1/2蛋白的表达。综上所述，我们证实螺内酯通过抑制MR-Nox1/2/4介导的ROS的产生而抑制Aldo诱导的NRAM中Kv1.5的表达。(C)2019 Elsevier Inc.保留所有权利。
Our previous investigation indicated that angiotensin II (Ang II) enhances the expression of Kv1.5, a promising target for the treatment of atrial fibrillation (AF), by activating reactive oxygen species (ROS)-dependent phosphorylation of Smad 2/3 (forming P-Smad 2/3) and ERK 1/2 (forming P-ERK 1/2). A recent study indicated that aldosterone (Aldo) upregulates atrial Kv1.5 protein in a rat AF model, but the mechanism remains unknown. The present study aimed to clarify the mechanism underlying Aldo-induced Kv1.5 expression and to test whether spironolactone may modulate atrial Kv1.5. Our Western blot analysis indicated that the Aldo/mineralocorticoid receptor (MR) interacts with Ang II/AT(1)R in upregulating Kv1.5 expression in cultured neonatal atrial myocytes (NRAMs). Blockade of MR with spironolactone and of AT(1)R with losartan significantly suppressed Kv1.5 expression induction by combined Aldo and Ang II treatment. Aldo increased the protein expression of Noxl, Nox2 and Nox4, but this effect was abolished by spironolactone pretreatment. The Aldo-induced upregulation of Kv1.5 was also reversed by the Src protein tyrosine kinase family inhibitor PP2, the Nox2 inhibitor gp9lds-tat and the Noxl /Nox4 inhibitor GKT137831 but not by the Rac GTPase inhibitor NSC23766. Flow cytometry showed that the Aldo-induced ROS production was inhibited by spironolactone, PP2, gp9lds-tat and GKT137831. Spironolactone suppressed the Aldo-induced protein expression phosphorylated Src (P-Src), P-Smad 2/3 and P-ERK 1/2. In conclusion, we have demonstrated that spironolactone suppresses Aldo-induced Kv1.5 expression by attenuating MR-Nox1/2/4-mediated ROS generation in NRAMs. (C) 2019 Elsevier Inc. All rights reserved.