CRP as a biomediator of atherosclerosis and its intracellular signaling

近年来，C-反应蛋白（CRP）对血管细胞有直接的促动脉粥样硬化作用。我们研究了CRP对培养的牛内皮细胞（BAEC）的直接作用及其潜在的信号传导，发现人重组CRP与BAEC共同孵育可诱导派-1表达显著增加。用CRP刺激BAEC显著增加小GTdR RhoA活化。TAT-C3（RhoA抑制剂）和Y-27632（Rho激酶抑制剂）预处理显著抑制CRP诱导的派-1表达。CRP可显著增强NF-κ B活性，Y-27632可抑制其活化. Parthenoptera、SN 50和BAY 11.7082（NF-κ B抑制剂）显著阻断CRP介导的PAI. 1表达。这些数据表明，CRP激活Rho/Rho激酶信号，进而激活NF-κ B活性，导致BAEC表达派-1。这些观察结果为Rho/Rho激酶信号通路可能参与CRP诱导的动脉粥样硬化血栓形成提供了证据。高浓度葡萄糖（23 mM）刺激BAEC也增加了PAI. 1的表达。与CRP刺激相似，高糖刺激显著增加RhoA活化，Y-27632预处理显著阻断高糖诱导的派-1表达。高糖可显著增强NF-κ B活性，Y-27632预处理可抑制高糖诱导的派-1表达。NF-κ B抑制剂显著阻断高糖诱导的派-1表达。提示高糖诱导内皮细胞派-1表达是通过Rho/Rho激酶途径激活NF-κ B介导的。抑制Rho/Rho激酶信号通路可能成为糖尿病和代谢综合征的新靶点。

Recently it has become evident that C-reactive protein (CRP) has direct proatherothrombotic effects on vascular cells. We examined the direct effects of CRP on cultured bovine endothelial cells (BAEC) and investigated its underlying signaling.Incubation of BAEC with human recombinant CRP induced a significant increase in PAI-1 expression. Stimulation of BAEC with CRP significantly increased small GTPase RhoA activation. Pretreatment with TAT-C3 (RhoA inhibitor) and Y-27632 (Rho-kinase inhibitor) significantly inhibited CRP-induced PAI-1 expression. NF-_kB activity was markedly enhanced by CRP and pretreatment with Y-27632 inhibited its activation. Parthenolide, SN50 and BAY 11.7082 (NF-_KB inhibitors) significantly blocked CRP-mediated PAI.1 expression. These data suggested that CRP activates Rho/Rho-kinase signaling, which in turn activates NF-_KB activity, resulting in PAI-1 expression in BAEC. These observations provide evidence for the possible involvement of Rho/Rho-kinase signaling in CRP-induced atherothrombogenesis.The expression of PAI.1 was also increased in BAEC by the stimulation with high concentration of glucose (23 mM). Similar to the stimulation with CRP, stimulation with high glucose significantly increased RhoA activation and pretreatment with Y-27632 significantly blocked high glucose-induced PAI-1 expression. NF-_KB activity was also significantly enhanced by high glucose, and pretreatment with Y-27632 inhibited high glucose-induced PAI-1 expression. NF-_KB inhibitors significantly blocked high glucose-mediated PAI-1 expression. These data suggested that high glucose-induced PAI-1 expression in endothelial cells is mediated by NF-_KB activation through the Rho/Rho-kinase pathway. Inhibition of Rho/Rho-kinase signaling might be a novel target for diabetes and metabolic syndrome.