Apelin抑制TGF-β诱导的人肾小管上皮-间充质细胞转换  

Apelin inhibits TGFβ-induced human renal tubular epithelial-mesenchymal transition

作　　者：王丽妍[1] 刁宗礼[1] 张启东[1] 刘文虎[1] 

机构地区：[1]首都医科大学附属北京友谊医院肾内科,北京100050

出　　处：《基础医学与临床》2016年第8期1051-1056,共6页Basic and Clinical Medicine

基　　金：国家自然科学基金(81570660;81300607);北京市科技计划(D131100004713001)

摘　　要：目的探讨多肽Apelin对转化生长因子β(TGF-β)诱导的人肾小管上皮-间充质细胞转换(EMT)的抑制作用及其机制。方法体外培养人近端肾小管上皮细胞,分别给予含TGF-β1(2μg/L)和/或不同浓度Apelin-13的培养基孵育细胞48 h,设立6个实验组(每组n=5):对照组、TGF-β组、TGF-β+Apelin(10-8,10-7和10-6mol/L)组和Apelin(10-6mol/L)组。刺激结束后,用免疫荧光染色观察细胞的上皮标志物E-钙黏素(E-cadherin)、间充质标志物α-平滑肌肌动蛋白(α-SMA)的分布和表达。Western blot检测细胞中E-cadherin、α-SMA及Smads信号通路的主要信号分子p-Smad2/3、Smad2/3和Smad-7的蛋白表达。RT-PCR法检测细胞外基质纤维连接蛋白(FN)、Ⅰ型胶原(Col-Ⅰ)及细胞自身Apelin和APJ受体的mRNA表达量。结果与对照组相比TGF-β组细胞为长梭形,E-cadherin的表达减少,α-SMA的表达增多,细胞外基质FN和Col-Ⅰ的mRNA表达量也显著升高;TGF-β+Apelin组上述效应被显著抑制,且呈浓度依赖性。与TGF-β组相比,TGF-β+Apelin组细胞活化型Smads的水平降低(P<0.05),Smad7的表达增加(P<0.05)。TGF-β组细胞自身APJ受体的表达量显著升高(P<0.05),TGF-β+Apelin组上述效应受到抑制,且呈浓度依赖性。结论 Apelin干扰TGF-β/Smads信号通路从而抑制肾小管上皮细胞EMT;肾小管上皮细胞自身Apelin/APJ系统可能起到一定的代偿作用。Objective In this study, inhibitory effects of apelin on transforming growth factor-β （TGF-β） -induced epithelial-mesenchymal transition （EMT） in human proximal renal tubular epithelial cells were examined and relat- ed mechanism was elucidated. Methods Human proximal renal tubular epithelial ceils were cultured. Cells were incubated with TGF-β（2 μg/L） and/or different concentrations of Apelin-13 for 48 hours. Six groups were estab- hshed （ n = 5 in each group） ： Control group, TGF-β group, TGF-β ＋ Apelin（ 10 ^-8, 10 ^-7 and 10 ^-6mol/L） group, apelin（10^-6mol/L） group. Immunofluorescence was performed to visualize the distribution of epithelial marker E-cadherin and mesenchymal marker a-smooth muscle actin （a-SMA）. Western blot analysis was performed to determine the level of E-cadherin, α-SMA, and expression of key Smads signaling molecules p-Smad2/3,Smad2/3 and Smad-7. RT-PCR analysis was performed to evaluate the mRNA level of fibronectin and Collagen I , and expression of endogenous apelin and APJ. Results Cells in TGF-β group was long spindle shape, together with decreased expression Of E-cadherin and increased expression of α-SMA. Morever, transcripts of fibronectin and collagen mRNAs were also increased in TGF-β group. However, these effects were obviously inhibited in TGFβ ＋ Apelin group in a concentration-dependent manner. The level of p-Smad2/3 decreased （P 〈 0. 05 ）, while Smad7 increased（ P 〈 0. 05 ） in TGF-β ＋ Apelin group . In TGF-13 group, expression of APJ was upregulated （P 〈 0.05）. This effect was also inhibited in TGFβ ＋ Apelin group in a concentration-dependent manner. Conclusions This study provides evidence to prove that apelin protects against tubular EMT through antagonism of TGF-β/Smads pathway. The endogenous apelinergic system may promote some compensatory response in tubular EMT process.

关 键 词：上皮-间充质转换 APELIN 转化生长因子Β 信号通路 

分 类 号：R692[医药卫生—泌尿科学]