摘要
目的探讨应用血管内皮生长因子(VEGF165)干预肾小管上皮-间充质转化(EMT)过程中NOTCH信号系统的变化及其意义。方法(1)体外培养的人肾小管上皮细胞(HK2)分为转化生长因子-β1(TGF-β1,5μg/L)单独作用组(T组)和TGF-β1(5μg/L)+VEGF(100μg/L)共同作用组(T+V组),RT-PCR及Western blot方法检测不同作用时间点JAGGED-1、α-平滑肌肌动蛋白(α-SMA)的表达。(2)TGF-β1与不同浓度VEGF165(0.1、1、10和100μg/L)共同作用细胞24 h,激光共聚焦显微镜(CFMS)、RT-PCR及Western blot检测E-钙黏素、α-SMA、JAGGED-1、NOTCH1表达。结果(1)作用后24和48 h,T+V组α-SMA和JAGGED-1蛋白表达均明显低于T组(P<0.05)。(2)同TGF-β1单独作用组比较,VEGF165(100μg/L)与TGF-β1共同作用组的E-钙黏素表达明显增强,α-SMA、JAGGED-1及NOTCH1表达均明显降低(P<0.05)。结论VEGF可抑制TGF-β1诱导HK2细胞发生EMT,并同时下调EMT过程中JAGGED-1、NOTCH1分子表达,提示该效应可能是VEGF抑制EMT的机制之一。
Objective To examine the effect of VEGF165 on expressions of JAGGED-1 and NOTCH1 and the relationship between these expressions and epithelial-mesenchymal transition(EMT) induced by TGF-β1.MethodsCultured HK2 cells were incubated with TGF-β1(5 μg/L) in the absence(group T) or presence(group T+V) of VEGF165(100 μg/L),respectively.Expressions of α-SMA and JAGGED-1 mRNA were assessed with RT-PCR and the protein expressions were assessed with Western blot at different time points,respectively.In the other experiment,HK2 cells were divided into four groups: negative control,incubated with TGF-β1(5 μg/L) along,with VEGF165(100 μg/L) along,or with TGF-β1(5 μg/L) and VEGF165 at different concentrations(0.1,1,10,100 μg/L) for 24 hours.Confocal microscope was used to detect expressions of α-SMA and E-cadherin.Protein and mRNA expressions of α-SMA,JAGGED-1 and NOTCH1 were assessed with RT-PCR and Western blot,respectively.Results Protein expression of both α-SMA and JAGGED-1 significantly decreased in group T+V at 24 and 48 h as compared with group T(P0.05).VEGF165 reversed TGF β1-induced inhibition of E-cadherin and promotion of α-SMA,JAGGED-1 and NOTCH1 significantly(P0.05).Conclusion The results of the present study showed that VEGF165 may partially inhibit TGF-β1 induced EMT of HK2 cells in vitro,which is probably contributed to the repression of JAGGED-1 and NOTCH1 expressions.
出处
《基础医学与临床》
CSCD
北大核心
2010年第10期1029-1036,共8页
Basic and Clinical Medicine
基金
国家自然科学基金(30570854)