ROS and endothelial nitric oxide synthase (eNOS)-dependent trafficking of angiotensin II type 2 receptor begets neuronal NOS in cardiac myocytes.
ROS and endothelial nitric oxide synthase (eNOS)-dependent trafficking of angiotensin II type 2 receptor begets neuronal NOS in cardiac myocytes.
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ROS 和内皮一氧化氮合酶 (eNOS) 依赖性血管紧张素 II 2 型受体运输在心肌细胞中产生神经元 NOS。
DOI：
10.1007/s00395-015-0477-6
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发表时间：
2015-05
影响因子：
9.5
通讯作者：
Zhang YH
中科院分区：
文献类型：
--
作者：
Jang JH;Chun JN;Godo S;Wu G;Shimokawa H;Jin CZ;Jeon JH;Kim SJ;Jin ZH;Zhang YH
血管紧张素 II (Ang II) 是肥厚和心力衰竭的有效前体，可上调心肌中的神经元一氧化氮合酶（nNOS 或 NOS1）。在这里，我们研究 1 型和 2 型血管紧张素受体（AT1R 和 AT2R）的参与以及介导 Ang II 上调 nNOS 的分子机制。我们的结果表明，用 AT1R 或 AT2R 拮抗剂（氯沙坦，PD123319）和 ROS 清除剂（罗布麻宁、替隆或 PEG 过氧化氢酶）预处理左心室 (LV) 肌细胞可阻断 nNOS 的 Ang II 上调。表面生物素化或免疫细胞化学实验表明，Ang II 使质膜中的 AT1R 表达逐渐减少（内化），而 AT2R 表达增加（膜运输）。 AT1R 或 ROS 清除剂的抑制可阻止 Ang II 诱导的 AT2R 易位至质膜，表明 AT1R-ROS-AT2R 的排列。此外，Ang II 增加了 eNOS-Ser1177，但减少了 eNOS-Thr495，表明 eNOS 伴随激活。有趣的是，ROS 清除剂而非 AT2R 拮抗剂阻止了 eNOS 的 Ang II 激活。 NOS 抑制剂（L-NG-硝基精氨酸甲酯，L-NAME）或 eNOS 基因缺失（eNOS−/−）消除了 Ang II 诱导的 AT2R 膜运输、nNOS 蛋白表达和活性。从机制上讲，NO 供体硝普钠 (SNP) 会增强 AT2R 的 S 亚硝化作用。位点特异性诱变分析表明，AT2R 中的 C 端半胱氨酸 349 对于 AT2R 易位至质膜至关重要。综上所述，我们首次证明 Ang II 通过 AT1R/ROS/eNOS 依赖的 S-亚硝化和 AT2R 的膜易位上调 nNOS 蛋白表达和活性。我们的结果表明 AT1R 和 AT2R 之间存在一种新的串扰，在致病性刺激下通过心肌中的 eNOS 调节 nNOS。
Angiotensin II (Ang II), a potent precursor of hypertrophy and heart failure, upregulates neuronal nitric oxide synthase (nNOS or NOS1) in the myocardium. Here, we investigate the involvement of type 1 and 2 angiotensin receptors (AT1R and AT2R) and molecular mechanisms mediating Ang II-upregulation of nNOS. Our results showed that pre-treatment of left ventricular (LV) myocytes with antagonists of AT1R or AT2R (losartan, PD123319) and ROS scavengers (apocynin, tiron or PEG-catalase) blocked Ang II-upregulation of nNOS. Surface biotinylation or immunocytochemistry experiments demonstrated that AT1R expression in plasma membrane was progressively decreased (internalization), whereas AT2R was increased (membrane trafficking) by Ang II. Inhibition of AT1R or ROS scavengers prevented Ang II-induced translocation of AT2R to plasma membrane, suggesting an alignment of AT1R-ROS-AT2R. Furthermore, Ang II increased eNOS-Ser1177 but decreased eNOS-Thr495, indicating concomitant activation of eNOS. Intriguingly, ROS scavengers but not AT2R antagonist prevented Ang II-activation of eNOS. NOS inhibitor (L-NG-Nitroarginine Methyl Ester, L-NAME) or eNOS gene deletion (eNOS−/−) abolished Ang II-induced membrane trafficking of AT2R, nNOS protein expression and activity. Mechanistically, S-nitrosation of AT2R was increased by sodium nitroprusside (SNP), a NO donor. Site-specific mutagenesis analysis reveals that C-terminal cysteine 349 in AT2R is essential in AT2R translocation to plasma membrane. Taken together, we demonstrate, for the first time, that Ang II upregulates nNOS protein expression and activity via AT1R/ROS/eNOS-dependent S-nitrosation and membrane translocation of AT2R. Our results suggest a novel crosstalk between AT1R and AT2R in regulating nNOS via eNOS in the myocardium under pathogenic stimuli.