ERK1/2信号转导途径在低切应力上调人脐静脉内皮细胞IL-8基因表达中的作用  

Effect of ERK1/2 on Low Shear Stress-induced Expression of IL-8 mRNA in Human Endothelial Cells

作　　者：成敏[1] 李毅[1] 陈槐卿[1] 聂永梅[1] 张怡[1] 刘小菁[2] 

机构地区：[1]四川大学华西医学中心生物医学工程研究室,成都610041 [2]四川大学华西医院心血管疾病研究室,成都610041

出　　处：《生物医学工程学杂志》2005年第2期230-234,共5页Journal of Biomedical Engineering

基　　金：国家自然科学基金资助项目 (3 0 3 70 3 75 )

摘　　要：血管内皮细胞位于血流和血管壁之间,除受化学因素的调节外还受力学因素的影响。切应力可通过刺激相应的力学感受系统来调节内皮细胞某些基因的表达,其中包括诱导内皮细胞表达IL- 8。为了阐明MAPK信号途径中的ERK1/ 2信号通路是否参与调控低切应力上调人脐静脉内皮细胞IL- 8基因表达,采用Western blot分析了低切应力(4.2 0 dyne/ cm2 )处理不同时间内皮细胞ERK1/ 2的磷酸化水平及TPK抑制剂Genistein,MEK抑制剂PD980 5 9对其磷酸化的影响;采用定量RT- PCR检测内皮细胞经低切应力刺激或给予阻断剂后再行切应力刺激等处理后IL- 8基因的表达。结果显示:(1)低切应力处理可引起内皮细胞ERK1/ 2蛋白磷酸化水平上调,其磷酸化水平与切应力作用时间有关,具有快速、双向性的特点(在刺激10 min时达到高峰,2 h左右降至未刺激水平) ,阻断剂Genistein和PD980 5 9处理后,ERK1/ 2磷酸化水平与低切应力刺激10 min比较明显降低;(2 )阻断剂Genistein,PD980 5 9可显著抑制低切应力所致的内皮细胞IL- 8m RNA上调。结果表明低切应力可通过ERK1/ 2信号途径上调人脐静脉内皮细胞IL- 8基因的表达。Fluid shear stress plays an important role in many physiological and pathophysiological processes of the cardiovascular system. It modulates vascular function and structure via stimulating mechanosensitive endothelial cell signal events. Previous studies have identified that the exposure of vascular endothelial cells to fluid mechanical forces can modulate the expressions of many genes, including IL-8 gene. In order to gain an insight into the role of extracellular signal regulated kinase （ERK1/2） signal pathway in the expression of IL-8 mRNA in human umbilical vein endothelial cells （HUVECs） under the stimulation by low shear stress （4.20 dyne/cm^2） ,we employed Western blot to measure phosphorylation of ERK1/2 and used quantitative reversal transcriptionpolymerase chain reaction （qRT-PCR） to assay the expression of IL-8 mRNA. The results showed： （1） Shear stress could activate ERK1/2 with a rapid, biphasic time course （maximum by 10 min and basal by 2 h）,the treatment of HUVECs with Genistein （a highly specific inhibitor of tyrosine protein kinase, TPK） or PD98059 （the inhibitor of mitogen-activated protein/extracellular signal regulated kinase kinase, MEK） culd prevent sheardependent activation of ERK1/2; （2） When treated with Genistein or PD98059,significant inhibition of IL-8 mRNA expression induced by low shear stress was observed in HUVECs. This in vitro study demonstrates that ERK1/2 plays an important role in IL-8 mRNA expression induced by low shear stress.

关 键 词：流体切应力 内皮细胞 细胞外信号调节激酶 白细胞介素-8 ERK1/2信号通路 人脐静脉内皮细胞 IL-8MRNA 低切应力 基因表达 信号转导途径 

分 类 号：R363[医药卫生—病理学]