p38抑制剂对低剪切应力诱导的人脐静脉内皮细胞株Fractalkine蛋白表达的影响

Effects of p38 inhibitor on protein expression of fractalkine induced by low shear stress in human umbilical vein endothelial cell line

目的探讨p38MAPK信号通路特异性抑制剂SB203580对血流低剪切应力诱导的人脐静脉内皮细胞株Fractalkine蛋白表达的影响。方法用M199生长液（含1%的青链霉素合剂和10%的胎牛血清）培养EA.hy926细胞至第2～5代,待细胞长满汇合后加载强度为4.58dyne/cm^2的剪切应力,分别处理0、5、10、30、60min。收集细胞提总蛋白,通过Western-blot技术检测剪切应力处理不同时间对EA.hy926细胞p38 MAPK磷酸化的影响,并分析p38 MAPK特异性抑制剂SB203580对p38磷酸化水平的抑制程度,观察SB203580对低剪切应力诱导的人脐静脉内皮细胞株Fractalkine蛋白表达的影响。结果低剪切应力处理可引起EA.hy926细胞p38蛋白磷酸化水平的上调,此过程与剪切应力作用时间有关,30min时磷酸化水平最高。用SB203580处理可明显抑制低剪切应力诱导的EA.hy926细胞Fractalkine蛋白表达上调过程。结论低剪切应力可激活p38信号转导途径,激活的p38信号分子可能参与调节低剪切应力诱导的内皮细胞Fractalkine表达上调过程,p38抑制剂能够下调低剪切应力诱导的Fractalkine的表达。

Objective Fluid shear stress is a frictional force exerted parallel to the vessel wall,to investigate the impacts of SB203580,a specific inhibitor of p38,on the expression of Fractalkine in endothelial cells（ECs）induced by low shear stress.Methods M199 growth medium（containing 1% penicillin-streptomycin combination and 10%fetal bovine serum）was used to culture the EA.HY926 cell line,after being cultured for two to five passages,were exposed to shear stress of 4.58dyne/cm^2 for different time（0,5,10,30 and 60min）.Cells were collected to extract total protein for western blotting analysis of p38 phosphorylation in different time.The inhibition level of p38 inhibitor on the phosphorylation of p38 was analyzed and then Fractalkine expression induced by low shear stress was detected.Results p38 phosphorylation was upregulated from the 5min exposure of low shear stress（4.58dyne/cm^2）and reach to the maximum level at 30 min.And the p38 phosphorylation regulated protein expression of p38 by corresponding signal transduction pathway.Additionally,p38 activation and the Fractalkine expression induced by low shear stress was inhibited by SB203580.Conclusion p38 MAPK signaling pathways could be activated by low shear stress.The activated p38 involved in low shear stress-induced Fractalkine expression.Inhibitor of p38 downregulated the expression of Fractalkine under low shear stress.