整合素β1-黏附斑激酶在心肌纤维化中的作用及机制*
2017-08-12林传钦翟秀丽邓托
林传钦,翟秀丽,邓托
(1.海南省农垦三亚医院 急诊科,海南 三亚 572000;2.海南省三亚市三林医院 防治科,海南 三亚 572025)
整合素β1-黏附斑激酶在心肌纤维化中的作用及机制*
林传钦1,翟秀丽2,邓托1
(1.海南省农垦三亚医院 急诊科,海南 三亚 572000;2.海南省三亚市三林医院 防治科,海南 三亚 572025)
目的初步探讨整合素β1-黏附斑激酶(integrin β1-FAK)在心肌细胞纤维化中的作用与机制。方法将培养的心肌细胞随机分为对照组、血清脂肪酶(LPS)处理组、integrin β1抑制组、黏附斑激酶(FAK)抑制组及integrinβ1阻断+FAK抑制组。免疫荧光双标法检测原代心肌细胞纯度,逆转录聚合酶链反应(RT-PCR)与实时荧光定量聚合酶链反应(qRT-RCR)检测基质金属蛋白酶9(MMP-9)、转化生长因子β1(TGF-β1)、Ⅰ型胶原(Col1A1)、Ⅲ型胶原(Col3A1)和整合素β1(integrin β1)mRNA水平的变化,Western blot检测FAK的表达。结果①与对照组比较,LPS能够刺激心肌细胞上调MMP-9、TGF-β1、Col1A1、Col3A1及integrin β1表达;②与LPS组比较,integrin β1阻断可以抑制LPS诱导的TGF-β1、MMP-9、Col1A1及Col3A1信使核糖核酸(mRNA)的上调(P<0.05),并阻断LPS诱导的磷酸化FAK的激活(P<0.05);③FAK蛋白抑制剂PF-573228可抑制LPS诱导的TGF-β1和MMP-9 mRNA上调水平,同时加入integrin β1封闭性抗体显示相似的效果。结论Integrin β1阻断能抑制FAK的磷酸化,下调TGF-β1、MMP-9、Col1A1及Col3A1的表达,从而改善在持续炎症刺激条件下心肌细胞的纤维化反应进程,为未来临床治疗拓展新思路。
心肌纤维化;整合素;黏附斑激酶;血清脂肪酶
Abstract:ObjectiveTo study the effects and mechanisms of integrin β1-FAK on myocardial fibrosis.MethodsCells were randomly divided into five groups:the blank control group,the LPS-stimulated group,integrin β1blocking group,FAK blocking group,blocking integrin β1and FAK group.Double-immunostaining was used to test the purity of myocardial cells.RT-PCR and q-PCR were used to detect the gene expression of MMP-9,TGF-β,Col1A1,Col3A1 and integrin β1.Western blot method was used to detect the expression of FAK protein.ResultsCompared with those in the control group,the LPS-treated cells exhibited a significant increase of MMP-9,TGF-β,Col1A1,Col3A1 and integrin β1,while blocking the integrin β1prevented the increase in LPS-induced up-regulation of MMP-9,TGF-β,Col1A1,Col3A1 and integrin β1and inhibited the FAK phosphorylation.Furthermore,when the cells were treated with the FAK agonist,the expression of MMP-9 and TGF-β decreased,and it had similar effect with blocking integrin β1.ConclusionsOurstudy suggeststhatinhibition ofintegrin β1suppresses the FAK phosphorylation,and decreasesexpressons of MMP-9,TGF-β,Col1A1,Col3A1,which contributes to alleviate the development of myocardial fibrosis under the condition of continuous inflammation stimulation and provides new ideas for the future clinical treatment stimulated H9c2 cardiomyocytes.
Keywords:myocardial fibrosis;integrin;focal adhesion kinase;lipase
心肌纤维化(myocardial fibrosis,MF)是以胶原过度沉积以及细胞外基质增多为特征的慢性病理过程,其发展在一定程度上影响着心肌梗死、高血压病、肥厚性心肌病及心力衰竭等多种心血管疾病的预后及转归[1-2]。尽管目前已有许多研究试图去揭示心肌纤维化的形成机制及所涉及的相关信号通路,例如心肌张力/压力的改变,转化生长因子β1(transforming growth factor-beta 1,TGF-β1)信号通路的激活等[3-5],但是总体而言,心肌纤维化的机制仍未完全明了,尚需进一步研究阐明。目前已有研究表明,心肌纤维化涉及到细胞外基质(extracellular matrixc,ECM)的产生[6]。……
