Over-expression of PKGIα inhibits hypoxia-induced proliferation, Akt activation, and phenotype modulation of human PASMCs: The role of phenotype modulation of PASMCs in pulmonary vascular remodeling
Over-expression of PKGIα inhibits hypoxia-induced proliferation, Akt activation, and phenotype modulation of human PASMCs: The role of phenotype modulation of PASMCs in pulmonary vascular remodeling
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DOI：
10.1016/j.gene.2011.11.010
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发表时间：
2012-01-25
期刊：
影响因子：
3.5
通讯作者：
Lu, Kai-zhi
中科院分区：
文献类型：
--
作者：
Yi, Bin;Cui, Jian;Lu, Kai-zhi
肺动脉平滑肌细胞（PASMCs）的增殖在肺血管重构（PVR）中起重要作用。最近，它表明，血管平滑肌细胞表型调制是重要的，他们在其他疾病的增殖。然而，对PVR过程中PASMC表型调控在低氧诱导增殖中的作用及其分子机制的研究尚不清楚。在这项研究中，我们发现使用原代培养的人PASMCs，缺氧抑制内源性PKGI α的表达，这是逆转的转染与重组腺病毒含有全长cDNA的PKGI α（Ad-PKGI α）。Ad-PKGI α转染显著减弱了低氧诱导的PASMCs中平滑肌α-肌动蛋白（SM-alpha-actin）、肌球蛋白重链（MHC）和钙调蛋白表达的下调，表明低氧诱导的表型调节被阻断。此外，流式细胞术和H-3-TdR掺入表明，低氧诱导的PASMC增殖受到PKGI α上调的抑制。这些结果表明，增强PKGI α表达抑制低氧诱导的PASMC表型调节，并可显著逆转PASMC的增殖。此外，我们的前期工作已经证明，Akt蛋白在缺氧诱导的人PASMCs增殖过程中被激活。有趣的是，我们发现当PASMC表型调节被Ad-PKGI α阻断时，Akt不被缺氧激活。这一结果表明，阻断表型调节可能是一个关键的上游调控目标。(C)2011 Elsevier B.V.保留所有权利。
The proliferation of pulmonary artery smooth muscle cells (PASMCs) plays a role in pulmonary vascular remodeling (PVR). Recently, it was shown that vascular smooth muscular cell phenotype modulation is important for their proliferation in other diseases. However, little is known about the role of human PASMC phenotype modulation in the proliferation induced by hypoxia and its molecular mechanism during PVR. In this study, we found using primary cultured human PASMCs that hypoxia suppressed the expression of endogenous PKGI alpha, which was reversed by transfection with a recombinant adenovirus containing the full-length cDNA of PKGI alpha (Ad-PKGI alpha). Ad-PKGI alpha transfection significantly attenuated the hypoxia-induced downregulation of the expression of smooth muscle a-actin (SM-alpha-actin), myosin heavy chain (MHC) and calponin in PASMCs, indicating that hypoxia-induced phenotype modulation was blocked. Furthermore, flow cytometry and H-3-TdR incorporation demonstrated that hypoxia-induced PASMC proliferation was suppressed by upregulation of PKGI alpha. These results suggest that enhanced PKGI alpha expression inhibited hypoxia-induced PASMC phenotype modulation and that it could reverse the proliferation of PASMCs significantly. Moreover, our previous work has demonstrated that Akt protein is activated in the process of hypoxia-induced proliferation of human PASMCs. Interestingly, we found that Akt was not activated by hypoxia when PASMC phenotype modulation was blocked by Ad-PKGI alpha. This result suggests that blocking phenotype modulation might be a key up-stream regulatory target. (C) 2011 Elsevier B.V. All rights reserved.