整合素与钙通道协同调节人肾小管上皮细胞转分化过程及其机制  

Research on the co-modulation effects of integrin and voltage-dependent Ca^(2+) channels on the transition of tubular epithelial to myofibroblast

作　　者：孙勇[1] 刘建国[1] 

机构地区：[1]华中科技大学同济医学院附属协和医院,湖北武汉430022

出　　处：《山东医药》2007年第8期7-9,共3页Shandong Medical Journal

基　　金：湖北省卫生厅科研基金项目(3-B5)

摘　　要：目的用转化生长因子-β1(TGF-β1)诱导人肾小管上皮细胞(HK-2)转分化,探讨转分化过程中可能的细胞信号转导机制。方法25 ml TGF-β1(5 ng/ml)刺激HK-2,用特异性细胞外信号调节激酶(ERK)抑制剂PD98059(25μmol/L)和(或)钙通道拮抗剂Nifedipine(10μmol/L)处理;于不同时间段分别用免疫荧光、S-P法和免疫印迹法检测黏着斑激酶(FAK)、整合素β1(β1-Integrin)。结果相比空白组TGF-β1成功诱导HK-2转分化;TGF-β1刺激15 min后FAK-Tyr397磷酸化增强,60 min达顶峰。相比TGF-β1对照组,PD98059使FAK-Tyr397的磷酸化减弱(P<0.05),而Nifedipine无明显抑制作用(P>0.05),两者协同作用明显(P<0.01);PD98059使FAK蛋白表达呈时间依赖性减弱(P<0.05),PD98059及Nifedipine均呈时间依赖性抑制β1-Integrin表达(P<0.05),二者协同作用明显(P<0.01)。结论TGF-β1与Integrin信号通路之间通过ERK/FAK相互作用;钙通道参与调节FAK活化及FAK与β1-Integrin的表达。[Objective] Using transforming growth factor （TGF-β1）to induce the transdifferentiation （EMT） of HK-2 so as to explore the possible mechanism of molecular signal transduction during the EMT process. [Methods] HK-2 cells were stimulated with TGF-β1, and then were treated with PD98059（25μmol/L）and/or Nifedipine（10μmolol/L）. Considering the E-Cadherin andα-SMA as the indicator of EMT, used immunohistochemistry and Western-blot to observe the expression of FAK and phospho-FAK （Tyr397）,used immunoflourescence to observe Integrin-β1. [Results] Compared with the control group, the expression of E-Cadherin mRNA decreased gradually while the α-SMA mRNA increased in the TGF-β1 group; the phosphorylation effects of FAK-Tyr397 enhanced after 15 min of the TGF-β1 stimulation, and reached to the peak after 60 min. Contrasted to the TGF- β1 group, PD98059 reduced the phosphorylation effects of FAK-Tyr397 （P〈0.05）while Nifedipine didn＇t show obvious inhibitory effect on it （P〉0.05）,and they had synergistic effects for the phosphorylation level （P〈 0. 01）; PD98059 caused a time-dependent reduction of the expression of FAK protein, while Nifedipine didn＇t show obvious inhibitory effect on it （P〉0.05）, and they had synergistic effects （P〈0. 01）. Both of PD98059 and Nifedipine had a time-dependent inhibitory effects on β1-Integrin＇s expression（P〈0. 05）, and their synergistic effect was much stronger（P（0.01）. [Conclusions] During the transition process of tubular epithelial to myofibroblast, the signal transduction between TGF-β1 and Integrin interacted through ERK/FAK, calcium channels co-modulated the activation of FAK as well as the esxpression of FAK and β1-Integrin.

关 键 词：上皮细胞 黏着斑激酶 整合素 钙通道 转化生长因子Β1 

分 类 号：R692.5[医药卫生—泌尿科学]