C反应蛋白促肺动脉平滑肌细胞增殖的机制研究

目的观察C反应蛋白(CRP)对培养的肺动脉平滑肌细胞(hPASMCs)增殖的影响,探讨CRP对肺血管疾病的可能作用。方法细胞培养液中,加CRP 0,5,10,20,50,100,200 mg/L培养,依次为Ctrl组、CRP 5组、CRP 10组、CRP 20组、CRP 50组、CRP 100组、CRP 200组。细胞培养液中先加入Wortmannin 1μmol/L,PD098059 20μmol/L和Bay117082 10μmol/L,依次为Wort组、PD组和Bay组,2 h后再加入CRP 100 mg/L培养24 h。各组均加入5'-溴脱氧尿嘧啶共培养4 h测细胞增殖,应用Western blot方法检测细胞外信号调节酶(ERK)1/2和蛋白激酶B(Akt)蛋白表达情况。以非变性凝胶电泳迁移率方法检测NF-κB的激活。结果 CRP刺激hPASMCs的增殖呈浓度依赖性。与Ctrl组比较,除CRP 10组外,各CRP组细胞增殖倍数的差异均有统计学意义(P<0.05,P<0.01),与CRP 100组比较,Wort组、PD组和Bay组细胞增值明显下降(P<0.01)。CRP呈浓度依赖性诱导NF-κB激活,与CRP 100组比较,Wort组和Bay组抑制NF-κB激活。与Ctrl组比较,CRP 10组起p-Akt和ERK1/2表达增加。与CRP 100组比较,Wort组p-Akt表达下降,PD组p-ERK1/2表达下降。结论 CRP浓度依赖性地促进hPASMCs的增殖。CRP通过激活信号通路磷脂酰肌醇3激酶/Akt,丝裂原活化蛋白激酶/ERK1/2和NF-κB介导促增殖作用。

Mechanisms of pulmonary artery smooth cell proliferation induced by C-reactive protein

Objective Previous data also showed that CRP level was an independent predictor of systolic pulmonary artery pressure,which suggested that CRP may play a key role in the pathogenesis of pulmonary hypertension.Then,we examined the potential effects and mechanisms of CRP on proliferation in human pulmonary artery smooth muscle cells(hPASMCs).Methods hPASMCs were cultured and stimulated by different concentration of CRP(5-200μg/ml) for 24 h.Using BrDU incorporation assay,we studied the effects of CRP on proliferation of hPASMCs. The activation of ERKl/2,Akt were examined by using Western blotting,and the activity of NF-κB was evaluated by electrophoretic mobility shift assay.Results CRP increased the proliferation of hPASMCs in a dose-dependent manner.CRP increased the expression of Akt and ERK1/ 2 phosphorylation,but had no influence on total protein;also,CRP induced the activation of NF-κB.Conclusion The data suggest that CRP exerts promote the proliferation of hPASMCs in a concentration-dependent way,and CRP mediates the proliferation-promoting effects via activation of Akt,ERKl/2,and NF-kB signaling pathways.