Heterodimerization With 5-HT2BR Is Indispensable for β2AR-Mediated Cardioprotection
Heterodimerization With 5-HT2BR Is Indispensable for β2AR-Mediated Cardioprotection
复制标题
5-HT(2B)R 异二聚对于 β(2)AR 介导的心脏保护是必不可少的。
DOI：
10.1161/circresaha.120.317011
复制
发表时间：
2021-01-22
影响因子：
20.1
通讯作者：
Xiao，Rui-Ping
中科院分区：
文献类型：
--
作者：
Song，Ying;Xu，Chanjuan;Xiao，Rui-Ping
β2-肾上腺素受体（β2-adrenoceptor，β2-AR）是一种典型的G蛋白偶联受体（G protein-coupled receptor，GPCR），与G蛋白和G蛋白偶联。β2-AR的刺激对患有心力衰竭的人类和动物有益，大概是因为它激活下游Gi-PI 3 K-Akt细胞存活途径。心脏β2-AR信号可以通过与其他GPCRs的串扰或异二聚化来调节，但这种类型的调节的生理和病理生理意义尚未得到充分证明。在这里，我们的目的是研究β2-肾上腺素能刺激的潜在心脏保护作用与亚型选择性激动剂，（R，R '）-4-甲氧基-1-萘基非诺特罗（MNF），并阐明其潜在机制，特别强调β2-AR与另一种GPCR，5-羟色胺受体2B的异二聚体化的作用。方法和结果利用药理学、遗传学和生物物理学的蛋白质-蛋白质相互作用方法，我们研究了β2-激动剂MNF，并在小鼠体内和用阿霉素、过氧化氢（H2 O2）或缺血/再灌注损伤的培养的啮齿动物心肌细胞中探索潜在的机制。在阿霉素（Dox）治疗的小鼠中，MNF降低了死亡率和体重减轻，同时改善了心脏功能和心肌细胞活力。MNF还能减轻心肌缺血/再灌注损伤。在培养的啮齿动物心肌细胞中，MNF抑制Dox、H2 O2或缺氧/复氧引起的DNA损伤和细胞死亡。从机制上讲，我们发现MNF或另一种β2-激动剂锌特罗显著促进β2-AR与5-HT 2BR的异源二聚化。上调异源二聚体化的5-HT 2BR和β2-AR增强β2-AR刺激的Gi-Akt信号和心脏保护作用，而敲低或药物抑制5-HT 2BR则减弱β 2-AR刺激的Gi-Akt信号和心脏保护作用。
RationaleThe β2-adrenoceptor (β2-AR), a prototypical GPCR (G protein-coupled receptor), couples to both Gsand Giproteins. Stimulation of the β2-AR is beneficial to humans and animals with heart failure presumably because it activates the downstream Gi-PI3K-Akt cell survival pathway. Cardiac β2-AR signaling can be regulated by crosstalk or heterodimerization with other GPCRs, but the physiological and pathophysiological significance of this type of regulation has not been sufficiently demonstrated.ObjectiveHere, we aim to investigate the potential cardioprotective effect of β2-adrenergic stimulation with a subtype-selective agonist, (R,R’)-4-methoxy-1-naphthylfenoterol (MNF), and to decipher the underlying mechanism with a particular emphasis on the role of heterodimerization of β2-ARs with another GPCR, 5-hydroxytryptamine receptors 2B (5-HT2BRs).Methods and ResultsUsing pharmacological, genetic and biophysical protein-protein interaction approaches, we studied the cardioprotective effect of the β2-agonist, MNF, and explored the underlying mechanism in both in vivo in mice and cultured rodent cardiomyocytes insulted with doxorubicin, hydrogen peroxide (H2O2) or ischemia/reperfusion. In doxorubicin (Dox)-treated mice, MNF reduced mortality and body weight loss, while improving cardiac function and cardiomyocyte viability. MNF also alleviated myocardial ischemia/reperfusion injury. In cultured rodent cardiomyocytes, MNF inhibited DNA damage and cell death caused by Dox, H2O2or hypoxia/reoxygenation. Mechanistically, we found that MNF or another β2-agonist zinterol markedly promoted heterodimerization of β2-ARs with 5-HT2BRs. Upregulation of the heterodimerized 5-HT2BRs and β2-ARs enhanced β2-AR-stimulated Gi-Akt signaling and cardioprotection while knockdown or pharmacological inhibition of the 5-HT2BR attenuated β2-AR-stimulated Gisignaling and cardioprotection.ConclusionsThese data demonstrate that the β2-AR-stimulated cardioprotective Gisignaling depends on the heterodimerization of β2-ARs and 5-HT2BRs.