Wang Chao-Hung, Li Shu-Hong, Weisel Richard D, Fedak Paul W M, Dumont Aaron S, Szmitko Paul, Li Ren-Ke, Mickle Donald A G, Verma Subodh
Division of Cardiac Surgery, University of Toronto, Toronto, Ontario, Canada.
Circulation. 2003 Apr 8;107(13):1783-90. doi: 10.1161/01.CIR.0000061916.95736.E5. Epub 2003 Mar 17.
Accumulating evidence suggests that C-reactive protein (CRP), in addition to predicting vascular disease, may actively facilitate lesion formation by inciting endothelial cell activation. Given the central importance of angiotensin type 1 receptor (AT1-R) in the pathogenesis of atherosclerosis, we examined the effects of CRP on AT1-R expression and kinetics in vascular smooth muscle (VSM) cells. In addition, the effects of CRP on VSM migration, proliferation, and reactive oxygen species (ROS) production were evaluated in the presence and absence of the angiotensin receptor blocker, losartan. Lastly, the effects of CRP (and losartan) on neointimal formation were examined in vivo in a rat carotid angioplasty model.
The effects of human recombinant CRP (0 to 100 microg/mL) on AT1-R transcript, mRNA stability, and protein expression were studied in cultured human VSM cells. AT1-R binding was assessed with 125I-labeled angiotensin II (Ang II). VSM migration was assessed with wound cell migration assays, whereas VSM proliferation was determined with [3H]-incorporation and cell number. The effects of CRP (and losartan) on Ang II-induced ROS production were evaluated by 2',7'-dichlorofluorescein fluorescence. Lastly, the effects of CRP (and losartan) on neointimal formation, VSM cell migration, proliferation, and matrix formation were studied in vivo in a rat carotid artery balloon injury model. CRP markedly upregulated AT1-R mRNA and protein expression and increased AT1-R number on VSM cells. CRP promoted VSM migration and proliferation in vitro and increased ROS production. Furthermore, CRP potentiated the effects of Ang II on these processes. In the rat carotid artery angioplasty model, exposure to CRP resulted in an increase in cell migration and proliferation, collagen and elastin content, and AT1-R expression, as well as an increase in neointimal formation; these effects were attenuated by losartan.
CRP, at concentrations known to predict cardiovascular events, upregulates AT1-R-mediated atherosclerotic events in vascular smooth muscle in vitro and in vivo. These data lend credence to the notion that CRP functions as a proatherosclerotic factor as well as a powerful risk marker.
越来越多的证据表明，C反应蛋白（CRP）除了可预测血管疾病外，还可能通过刺激内皮细胞活化而积极促进病变形成。鉴于1型血管紧张素受体（AT1-R）在动脉粥样硬化发病机制中的核心重要性，我们研究了CRP对血管平滑肌（VSM）细胞中AT1-R表达及动力学的影响。此外，在存在和不存在血管紧张素受体阻滞剂氯沙坦的情况下，评估了CRP对VSM迁移、增殖和活性氧（ROS）产生的影响。最后，在大鼠颈动脉血管成形术模型中体内研究了CRP（和氯沙坦）对新生内膜形成的影响。
在培养的人VSM细胞中研究了重组人CRP（0至100μg/mL）对AT1-R转录本、mRNA稳定性和蛋白表达的影响。用125I标记的血管紧张素II（Ang II）评估AT1-R结合。用伤口细胞迁移试验评估VSM迁移，而用[3H]掺入和细胞数量测定VSM增殖。通过2',7'-二氯荧光素荧光评估CRP（和氯沙坦）对Ang II诱导的ROS产生的影响。最后，在大鼠颈动脉球囊损伤模型中体内研究了CRP（和氯沙坦）对新生内膜形成、VSM细胞迁移、增殖和基质形成的影响。CRP显著上调AT1-R mRNA和蛋白表达，并增加VSM细胞上的AT1-R数量。CRP在体外促进VSM迁移和增殖，并增加ROS产生。此外，CRP增强了Ang II对这些过程的作用。在大鼠颈动脉血管成形术模型中，暴露于CRP导致细胞迁移和增殖、胶原蛋白和弹性蛋白含量以及AT1-R表达增加，以及新生内膜形成增加；氯沙坦减弱了这些作用。
在已知可预测心血管事件的浓度下，CRP在体外和体内上调血管平滑肌中AT1-R介导的动脉粥样硬化事件。这些数据支持了CRP作为促动脉粥样硬化因子以及强大风险标志物的观点。
