血管紧张素Ⅱ与其介导的蛋白质酪氨酸激酶JAK2信号通路在缺血再灌注肾损伤时小管上皮细胞逆向分化中的作用

目的 探讨血管紧张素(Ang)Ⅱ与其介导的蛋白酪氨酸激酶JAK2信号通路在急性缺血再灌注肾损伤模型中发生的肾小管上皮细胞逆向分化的作用机制.方法 (1)建立Wistar大鼠急性缺血再灌注肾损伤模型,采用放射免疫法检测肾脏局部AngⅡ的水平变化,采用免疫组织化学ABC法和RT-PCR,观察间充质细胞表面标记α-平滑肌肌动蛋白(α-SMA)的表达.(2)模拟高、中、低浓度的肾素-血管紧张素系统(RAS)环境,体外观察培养的肾小管上皮细胞(NRK-52E)逆向分化的情况.(3)先后阻断AngⅡ受体(AT2R)及其介导的Ang Ⅱ信号转导通路的JAK2,研究AngⅡ与JAK2通路对肾小管上皮细胞逆向分化的影响.结果 (1)肾脏缺血再灌注损伤后0、24、48、72、96、120 h,局部AngⅡ含量持续增高,分别为(406.7±106.1)、(463.0±112.9)、(526.6±128.3)、(649.5±131.5)、(875.4±150.2)、(980.8±155.2)ng/L,P<0.05.(2)缺血再灌注后48 h,肾小管上皮细胞开始表达α-SMA mRNA及蛋白质.(3)高浓度(10-7mol/L)Ang Ⅱ刺激可诱导体外培养的肾小管上皮细胞表达α-SMA,且呈剂量和时间依赖性.10-9,mol/L浓度AngⅡ刺激30 min时,α-SMA表达水平最高.无论是阻断AT2R抑或JAK2信号通路,肾小管上皮细胞表达α-SMA均明显受到抑制.结论 急性缺血再灌注损伤时肾小管上皮细胞可向间充质细胞逆向分化,局部RAS启动与其密切相关.AngⅡ可能通过AT2R及其介导的JAK2信号通路促发肾小管细胞的逆向分化.     

Apelin抑制TGF-β诱导的人肾小管上皮-间充质细胞转换

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(P0.05),Smad7的表达增加(P0.05)。TGF-β组细胞自身APJ受体的表达量显著升高(P0.05),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。     

雷帕霉素对人肾小管上皮-肌成纤维细胞转化的抑制作用

目的 探讨雷帕霉素(Rapamycin,RAPA)对体外培养的人肾小管上皮细胞发生上皮肌成纤维细胞转化(Epithelial-Myofibroblast Transition,EMT)的作用,以及该作用与上皮细胞中锌指蛋白(Snail)基因水平变化的关系.方法 体外培养的人近端肾小管上皮细胞(HKC),分为阴性对照组、转化生长因子β-1(TGF-β1)(1 μg/L)阳性对照组和TGF-β1 RAPA组.TGF-β1 RAPA组不同浓度的雷帕霉素(0.1 μg/L,1 μg/L,10 μg/L,100 μg/L)与TGF-β1(1 μg/L)共同作用,各组作用时间均为48 h.用间接免疫荧光双染、RT-PCR、Western Blot方法分别检测细胞平滑肌细胞肌动蛋白(α-SMA)、E-钙黏素(E-cadherin)表达,同时用RT-PCR方法检测细胞Snail mRNA水平的变化.再选取最大作用浓度的雷帕霉素作用不同时间(12 h、24 h、48 h、72 h),用RT-PCR、Western Blot方法检测α-SMA表达水平变化.结果 间接免疫荧光双染、RT-PCR、Western Blot方法检测均表明,TGF-β1阳性作用组较阴性对照组HKC细胞α-SMA mRNA及蛋白表达水平显著增强(P＜0.05),而E-cadherin表达则几乎消失,Snail mRNA表达水平显著增强(P＜0.05).与阳性对照组相比,雷帕霉素(10 μg/L,100 μg/L)与TGF-β1共同作用组HKC细胞α-SMA mRNA及蛋白表达水平显著降低(P＜0.05),而E-cadherin表达则有部分恢复,显著高于阳性对照组(P＜0.05),而Snail mRNA表达水平比阳性对照组显著降低(P＜0.05).雷帕霉素以浓度依赖方式抑制TGF-β1诱导的HKC细胞Snail mRNA表达.结论 应用体外培养的肾小管上皮细胞研究表明,雷帕霉素具有抑制肾小管上皮细胞EMT的作用.此作用可能与该药诱导的Snail表达下调有关.     

蟾蜍灵抑制TGF-β1诱导人肾小管上皮细胞-间充质细胞系转换

目的探讨蟾蜍灵对转化生长因子(TGF)-β1诱导的人肾小管上皮细胞-间充质细胞转换的影响。方法将体外培养的人近端肾小管上皮细胞系(HK-2)细胞分为3组:1)对照组;2)TGF-β1组:在细胞培养基中加入TGF-β1(浓度为5μg/L);3)蟾蜍灵+TGF-β1组:在细胞培养基中分别加入蟾蜍灵和TGF-β1(浓度为5μg/L),按蟾蜍灵的浓度分为A、B、C 3个亚组:分别为1×10~(-9)、1×10~(-8)和1×10~(-7)mol/L。72 h后,用倒置相差显微镜观察细胞形态;用实时定量PCR、蛋白印迹法和免疫荧光检测细胞α-平滑肌肌动蛋白(α-SMA)和E-钙黏蛋白(E-cadherin)的表达。结果 TGF-β1组HK-2细胞从原有典型的铺路石样上皮细胞转变为长梭形肌成纤维细胞;胞质内大量表达α-SMA,同时E-cadherin的表达明显减少(P0.01);蟾蜍灵处理后TGF-β1诱导的细胞形态学改变减轻,胞质内α-SMA的表达减少(P0.05),同时E-cadherin的表达明显恢复,且呈剂量依赖性。结论蟾蜍灵能有效抑制TGF-β1诱导的HK-2细胞转换,对肾脏病治疗具有潜在应用前景。     

颗粒蛋白前体(PGRN)促进小鼠乳腺癌4T1细胞上皮间质转化与侵袭和迁移

目的探讨颗粒蛋白前体(PGRN)对小鼠乳腺癌4T1细胞侵袭和迁移的影响及其机制。方法采用1μg/mL PGRN处理乳腺癌4T1细胞24 h,通过Transwell~(TM)侵袭实验检测4T1细胞的侵袭能力、划痕实验检测细胞的迁移能力,实时荧光定量PCR检测4T1细胞上皮钙黏蛋白(E-cadherin)、波形蛋白(vimentin)的mRNA水平,Western blot法检测4T1细胞E-cadherin、 vimentin、细胞外信号调节激酶1/2(ERK1/2)、磷酸化的ERK1/2(p-ERK1/2)蛋白水平。采用1μg/mL PGRN与ERK1/2信号通路抑制剂U0126(10μmol/L)同时处理4T1细胞后,前述方法检测4T1细胞侵袭及迁移能力及E-cadherin、 vimentin与p-ERK蛋白表达的变化。结果乳腺癌4T1细胞经PGRN处理后,其侵袭及迁移能力明显增强;E-cadherin表达下降,vimentin表达升高,p-ERK1/2的表达增强;抑制ERK1/2信号通路后,PGRN促进乳腺癌4T1细胞侵袭、迁移及上皮间质转化(EMT)的能力被明显抑制。结论 PGRN可通过促进EMT及激活ERK1/2通路促进乳腺癌4T1细胞的侵袭及迁移。     

TAK1通过调控p38 MAPK信号通路影响肾小管上皮细胞纤维化

目的:探讨转化生长因子β激活激酶1(TAK1)对肾小管上皮细胞纤维化的影响及机制。方法:以肾小管上皮细胞HK-2作为研究对象,用转化生长因子β1(TGF-β1)诱导肾小管上皮细胞纤维化,以real-time PCR和Western blot检测细胞中TAK1表达的变化。用TAK1 shRNA慢病毒感染肾小管上皮细胞,以real-time PCR和Western blot检测其对TGF-β1刺激下肾小管上皮细胞中TAK1表达的影响以检测干扰效果。ELISA法检测细胞分泌的I型胶原和III型胶原水平,Western blot法检测细胞中α-平滑肌肌动蛋白(α-SMA)、结缔组织生长因子(CTGF)和磷酸化的p38 MAPK(p-p38 MAPK~(Thr 180/Tyr 182))的蛋白水平。用p38 MAPK激活剂处理已敲减TAK1表达的肾小管上皮细胞,检测其对细胞分泌I型胶原和III型胶原的影响及对细胞中α-SMA、CTGF和p-p38 MAPK~(Thr 180/Tyr 182)蛋白水平的影响。结果:TGF-β1可以明显上调肾小管上皮细胞中TAK1的表达水平。TAK1 shRNA可明显下调TGF-β1刺激下的肾小管上皮细胞中TAK1的表达水平。TGF-β1处理后的肾小管上皮细胞分泌I型胶原和III型胶原增多,细胞中α-SMA、CTGF和p-p38 MAPK~(Thr 180/Tyr 182)蛋白水平升高。敲减TAK1表达可以明显抑制TGF-β1诱导的肾小管上皮细胞分泌I型胶原和III型胶原,减少细胞中α-SMA、CTGF和p-p38 MAPK~(Thr 180/Tyr 182)的蛋白水平(P0.05)。p38 MAPK激活剂处理可以逆转敲减TAK1表达对肾小管上皮细胞分泌I型胶原和III型胶原及α-SMA、CTGF和p-p38 MAPK~(Thr 180/Tyr 182)蛋白水平的抑制作用。结论:敲减TAK1表达能够通过抑制p38 MAPK信号通路而降低TGF-β1诱导的肾小管上皮细胞纤维化水平。     

血管紧张素-(1-7)对血管紧张素Ⅱ诱导的大鼠肾小管上皮细胞转分化的影响

目的:探讨血管紧张素-(1-7)[Ang-(1-7)]对血管紧张素Ⅱ( AngⅡ)诱导的大鼠肾小管上皮细胞(NRK52E)表型转化及细胞外基质分泌的影响.方法:体外培养NRK52E细胞,经Ang-(1-7)和AntgⅡ(终浓度均为1×10-6 mol/L)干预24、48、72、96 h后,应用细胞免疫化学法检测E-cadherin,α-SMA的表达;应用ELISA法检测细胞上清液中Ⅰ型胶原(Col I)和纤维黏连蛋白(FN)的表达;采用实时荧光定量PCR( Real-timePCR)检测细胞中E-cadherin、α-SMA、Col I和FN mRNA表达水平的变化.结果:AngⅡ作用96h后,E-cadherin蛋白及mRNA表达显著减弱(P＜0.05),α-SMA、Col I、FN蛋白及mRNA表达显著增强(P＜0.05);同时加入Ang-(1-7)后,与AngⅡ组比较,E-cadherin蛋白及mRNA的表达增强(P＜0.05),α-SMA、Col I、FN蛋白及mRNA表达减弱(P＜0.05).结论:Ang-(1-7)能够抑制AngⅡ诱导的大鼠肾小管上皮细胞表型转化及细胞外基质的分泌.     

罗格列酮对高糖诱导的人肾小管上皮细胞血小板反应蛋白1和BMP-7表达的影响

目的:探讨罗格列酮(RSG)对高糖环境下人肾小管上皮细胞(HK-2)血小板反应蛋白1(TSP-1)和骨形成蛋白7(BMP-7)mRNA和蛋白表达的影响.方法:将体外培养的人肾小管上皮细胞分为正常糖对照组(NG)、高糖组(HG)、渗透浓度对照组(MG)、分别含RSG 5、10、20 μmol/L的高糖DMEM培养基培养的RSG干预组(R5、R10、R20),并于培养48 h后终止培养.免疫细胞化学方法检测人肾小管上皮细胞TSP-1、BMP-7、结缔组织生长因子(CTGF)蛋白的表达,RT-PCR法检测人肾小管上皮细胞中TSP-1、BMP-7、CTGF mRNA表达.结果:高糖环境下,HK-2细胞TSP-1、CTGF mRNA和蛋白表达明显升高(P<0.05),BMP-7 mRNA和蛋白表达明显降低(P<0.05),加入RSG后,HK-2细胞TSP-1、CTGF的表达较NG组明显降低(P<0.05),BMP-7的表达明显升高(P<0.05).结论:RSG可以抑制高糖诱导的人肾小管上皮细胞TSP-1、CTGF高表达,提高BMP-7的表达,具有一定的肾脏保护作用.     

木犀草素对人肝癌HepG2细胞株侵袭、迁移和黏附能力的影响

目的:探讨木犀草素对人肝癌HepG2细胞株侵袭、迁移和黏附能力的影响及其作用机制。方法:采用不同浓度木犀草素处理体外培养的人肝癌HepG2细胞株,Transwell实验检测细胞的侵袭能力,划痕实验检测细胞的迁移能力,黏附实验评价细胞的黏附能力,Western blot检测E-钙黏蛋白(E-cadherin)、N-钙黏蛋白(N-cadherin)、波形蛋白(vimentin)和Snai1蛋白的表达。结果:木犀草素可明显降低肝癌HepG2细胞的体外侵袭、迁移及黏附能力(P0.01),且在一定浓度范围内呈明显量效关系。木犀草素处理肝癌细胞后,上皮细胞标志蛋白E-cadherin表达明显上调,间质细胞标志蛋白N-cadherin和vimentin以及转录因子Snai1表达均明显下调,木犀草素对以上蛋白的调节呈明显浓度依赖性。结论:木犀草素体外具有抑制肝癌HepG2细胞株侵袭、迁移和黏附的作用,其作用机制可能与调控上皮-间质转化有关。     

转录因子Sp1促进肾小管上皮间质转化的体外实验研究

目的:研究转录因子Sp1促进肾小管上皮间质转化(EMT)以及肾脏纤维化的作用和机制.方法:用30 mL/L浓度的低氧培养肾小管上皮细胞HK-2,采用Real-time PCR及Western blot法分别检测细胞中转录因子Spl,E-cadherin和α-SMA的mRNA和蛋白表达水平.构建SP1基因的小干扰RNA载体,并将其转染低氧处理的HK-2肾小管上皮细胞.Real time PCR及Western blot法检测转录因子SP1对HK-2细胞EMT标志物的影响.结果:低氧处理后的HK-2细胞上皮标志物E-cadherin表达显著下降,而间皮标志物α-SMA的表达显著增加,提示HK-2细胞发生EMT.同时发现低氧处理后HK-2中转录因子Sp1的mRNA水平和蛋白水平表达逐渐增加.将Sp1的小干扰RNA载体转染HK-2细胞,得到下调Sp1表达的肾小管上皮细胞系.结果显示,与对照组相比,敲减Sp1的低氧处理的HK-2细胞中上皮细胞标志物E-cadherin 表达未见显著下降,而间质细胞标志物α-SMA的表达未见显著增加,提示此时的HK-2细胞未发生EMT.结论:转录因子Sp1可促进HK-2肾小管上皮细胞的EMT.     

Polarized M2c macrophages have a promoting effect on the epithelial-to-mesenchymal transition of human renal tubular epithelial cells

This study planned to explore the effects of M2c macrophages on epithelial-to-mesenchymal transition (EMT) of human renal proximal tubular epithelial cells (HK-2). Human monocytic leukaemia cells were induced by TPA and IL-10 to differentiate M2c macrophages. Subsequently HK-2 cells were co-cultured with the M2c macrophages in Transwell chamber. After 48?h of co-culturing the HK-2 cells were detected in the mRNA and protein expression of E-cadherin, α-SMA and vimentin with RT-PCR, immunofluorescence and Western blot respectively. Besides, the migration ability of the HK-2 cells was estimated with Transwell migration assay. ANOVA was used to compare the difference between groups and Student's t-test to conduct multiple comparisons of two groups. P?<?0.05 was considered statistically significant. The results showed that the mRNA and protein expression of α-SMA and vimentin of the HK-2 cells were increased but the E-cadherin decreased significantly after 48?h co-culturing with the M2c macrophages (P?<?0.05 or P?<?0.01). And the migration ability of HK-2 cells were also increased significantly (P?<?0.05). It may be concluded that polarized M2c macrophages may have a promoting effect on the EMT of HK-2 cells.     

Genistein ameliorates parathyroid hormone-induced epithelial-to-mesenchymal transition and inhibits expression of connective tissue growth factor in human renal proximal tubular cells

Introduction

Genistein, a soybean and soy-based product, has been reported to inhibit the growth of a wide range of cancer cells, but there is no evidence concerning its treatment of chronic kidney disease. The aim was to investigate whether genistein has potential to inhibit parathyroid hormone (PTH)-induced renal interstitial fibrosis.

Material and methods

Using human renal tubular epithelial HK-2 cells, α-smooth muscle actin (α-SMA) was assessed by using immunofluorescence detection. α-Smooth muscle actin, E-cadherin and connective tissue growth factor (CTGF) were measured by Western blot analysis. The promoter activity of the CTGF gene was examined by the luciferase reporter assay.

Results

When cells were treated with PTH (0.1 nM) for 48 h, α-SMA protein expression was induced significantly, the protein expression of E-cadherin decreased substantially, and the promoter activity of the CTGF gene as well as its mRNA and protein expression levels increased (p < 0.01). Interestingly, genistein effectively inhibited PTH-induced α-SMA expression, restored E-cadherin expression, decreased mRNA and protein expression of CTGF, and suppressed the promoter activity of CTGF in a dose-dependent manner.

Conclusions

Genistein has the ability to block the biomarker for renal transdifferentiation and epithelial-to-mesenchymal transition, α-SMA, following PTH treatment and inhibit CTGF expression in human renal tubular epithelial cells; these might be important modes of actions that contribute to genistein anti-fibrogenic effects and may have great implications for its potential in clinical treatment of renal interstitial fibrosis.     

激活法尼酯X受体上调核心蛋白聚糖表达对肾小管上皮细胞转分化的作用

目的研究激活法尼酯X受体(FXR)对核心蛋白聚糖(decorin)表达的变化及其对肾小管上皮细胞-间充质转分化的影响。方法 (1)采用不同浓度的FXR特异性激动剂CDCA及拮抗剂Guggulsterones处理肾小管上皮细胞(HK-2),观察decorin的mRNA和蛋白表达的变化;(2)将HK-2细胞分为对照组,TGF-β1诱导组(20 ng/ml),TGF-β1诱导加CDCA组(100μmol/L)和TGF-β1诱导加CDCA、Guggulsterones共处理组,48 h后观察各组细胞的形态变化,检测各组decorin、E-cadherin和α-SMA的mRNA和蛋白表达的情况。结果 (1)CDCA激活HK-2细胞FXR,decorin的mRNA和蛋白表达升高,且呈剂量依赖。在100μmol/L CDCA和不同浓度Guggulsterones共处理HK-2细胞,随着Guggulsterones浓度升高,decorin的mRNA和蛋白表达逐渐减低;(2)RT-PCR和Western blot显示,decorin在对照组、TGF-β1组无表达,在TGF-β1+CDCA组明显上调(与TGF-β1组比,P<0.05),在TGF-β1+CDCA+Guggulsterones组表达显著下降;E-cadherin在对照组高表达,在TGF-β1组显著下调,在TGF-β1+CDCA组显著上调(与TGF-β1组比,P<0.05),在TGF-β1+CDCA+Guggulsterones组表达显著下降;α-SMA在对照组无表达,在TGF-β1组显著上调,在TGF-β1+CDCA组显著下调(与TGF-β1组比,P<0.05),在TGF-β1+CDCA+Guggulsterones组表达显著上调。结论 CDCA激活肾小管上皮细胞FXR能够通过上调decorin的表达,从而抑制TGF-β1诱导的肾小管上皮细胞-间充质转分化。     

间充质干细胞条件培养液促进肺癌细胞上皮间质转化

BACKGROUND: The complex relationship between bone marrow mesenchymal stem cells and cancers severely limit the clinical application of mesenchymal stem cells. So it is urgent to study the role of mesenchymal stem cells in tumor growth and metastasis. OBJECTIVE: To explore the effect of human bone marrow mesenchymal stem cells on epithelial mesenchymal transition in non-small cell lung cancer A549 and PAa cells. METHODS: The A549 and PAa cells were cultured with mesenchymal stem cell supernatant (mesenchymal stem cell conditioned medium, MSCs-CM). The cellular morphology was observed under a microscope. The mRNA and protein expression of E-cadherin, N-cadherin, Vimentin, Slug, Snail, and Twist were determined by RT-PCR and western blot. Transwell and wound healing assay were used to detect the change of migration and metastatic ability. RESULTS AND CONCLUSION: Compared with the control group, the cellular morphology of experimental group showed mesenchymal-like changes. In response to MSCs-CM, there was decreased E-cadherin but increased N-cadherin, Vimentin and Slug, Snail, Twist at mRNA and protein levels compared with the control group (P < 0.05). The migration and metastatic abilities of the experimental group were also increased. So, human bone marrow mesenchymal stem cells can promote epithelial mesenchymal transition in A549 and PAa cells, and enhance the migration and metastatic abilities of A549 and PAa cells.       

阻断核心岩藻糖基化修饰抑制肾小管上皮细胞的间充质转化

目的: 探讨阻抑核心岩藻糖基化修饰对肾小管上皮细胞间充质转化(EMT)过程的影响。方法: 利用转化生长因子β₁(TGF-β₁)建立肾小管上皮HK-2细胞EMT的模型,应用RNAi技术沉默HK-2细胞的α-1,6-岩藻糖基转移酶(FUT8)基因表达,光镜下观察FUT8 基因沉默后细胞形态变化,免疫印迹及免疫细胞化学方法测定细胞表型标记物蛋白E-钙黏蛋白(E-cadherin)、N-钙黏蛋白(N-cadherin)、α-平滑肌肌动蛋白(α-SMA)和成纤维细胞特异性蛋白-1(FSP-1)的表达变化,流式细胞仪测定细胞凋亡。 结果: TGF-β₁孵育48 h后,HK-2细胞失去原有的上皮细胞形态,呈现纤维细胞形态,纤维细胞表型标记蛋白α-SMA、FSP-1及N-cadherin表达明显升高,而上皮细胞表型标记蛋白E-cadherin表达明显下降,同时伴有 FUT8 基因表达上调,细胞凋亡增加,而提前转染FUT8 siRNA能明显减弱上述这些反应。结论: FUT8催化的核心岩藻糖基化修饰参与HK-2细胞的EMT过程;阻断核心岩藻糖基化修饰,能有效阻断肾小管上皮细胞的EMT过程。     

STAT1的SUMO4修饰在高糖诱导的肾小管上皮细胞上皮-间叶性转化中的作用

目的探讨STAT1的SUMO4修饰与人近端肾小管上皮细胞(HK-2)表型转化的关系。方法将HK-2细胞分为空白对照组(NG,5.5 mmol/L葡萄糖)、高糖组(HG,30 mmol/L葡萄糖)、SUMO4-siRNA(转染SUMO4 siRNA)组、NC-siRNA(转染scrimble siRNA)组、UBC9-siRNA(转染UBC9 siRNA)组。采用免疫细胞化学、Western blot法检测E-cadherin、α-SMA、vimentin等的表达;双荧光素酶报告基因分析检测STAT1的转录活性;免疫共沉淀检测STAT1的SUMO4修饰。结果高糖刺激后,HK-2细胞中E-cadherin表达降低,而vimentin与α-SMA表达增高(P<0.05);高糖上调STAT1的SUMO4修饰;不论是SUMO4 siRNA转染还是UBC9 siRNA转染,均能显著提升STAT1的活性(P<0.01);同时SUMO4 siRNA转染可部分逆转高糖导致的E-cadherin和α-SMA表达变化(P<0.05)。结论抑制STAT1的SUMO4修饰增加STAT1的活性,缓解了高糖诱导的HK-2细胞的上皮-间叶性转化。     

1,25（OH）2D3对甲状旁腺素诱导的肾小管上皮细胞转分化和TGF-β1的表达的影响

目的:探讨1,25(OH)2D3对甲状旁腺素(PTH)诱导的肾小管上皮细胞转分化和转化生长因子-β1(TGF-β1)表达的影响。方法:人肾小管上皮细胞(HK-2细胞)培养在含50 mL/L FCS的DMEM/F12培养液中。对照组:加入等体积含50 mL/L FCS的DMEM/F12培养液;PTH刺激组:加入终浓度为10-10 mol/L PTH的含50 mL/L FCS的DMEM/F12培养液;PTH+1,25(OH)2D3干预组:加入10-10 mol/L PTH,同时加入不同浓度(10-10、10-9、10-8、10-7 mol/L)的1,25(OH)2D3。刺激HK-2细胞48 h。半定量RT-PCR法检测细胞中α-平滑肌肌动蛋白(α-SMA)和TGF-β1的基因表达;Western blot法检测细胞中α-SMA和TGF-β1的蛋白表达;免疫细胞化学法检测细胞中α-SMA的表达;ELISA法检测细胞培养上清液中TGF-β1的含量。结果:半定量RT-PCR结果显示,对照组HK-2细胞中几乎无α-SMA的mRNA表达,仅有少量的TGF-β1 mRNA表达;PTH刺激组α-SMA和TGF-β1mRNA表达量与对照组比较明显增加;PTH+1,25(OH)2D3干预组表达量比PTH刺激组显著降低,且随着1,25(OH)2D3浓度的升高呈一定的剂量依赖性(P<0.05)。Western blot结果显示,对照组HK-2细胞中无α-SMA的蛋白表达,仅有少量的TGF-β1蛋白表达;10-10 mol/L的PTH能够明显诱导HK-2细胞中α-SMA的蛋白表达,增加TGF-β1的蛋白表达量;PTH+1,25(OH)2D3干预组,α-SMA和TGF-β1的蛋白表达量比PTH刺激组显著降低(P<0.05)。免疫细胞化学法结果显示,对照组几乎无α-SMA阳性表达的细胞,PTH刺激组可见大量细胞α-SMA表达阳性;PTH+1,25(OH)2D3干预组α-SMA表达阳性的细胞数明显低于PTH刺激组(P<0.05)。ELISA结果显示,对照组细胞上清液中可检测到少量的TGF-β1,PTH刺激组含量显著升高,PTH+1,25(OH)2D3干预组与PTH刺激组比较含量明显降低(P<0.05)。结论:1,25(OH)2D3能够部分拮抗PTH诱导的HK-2细胞转分化和TGF-β1的表达。     

骨髓间充质干细胞体外向子宫内膜上皮细胞的分化

BACKGROUND: Previous studies have confirmed that as an exogenous origin of endometrial epithelial cells, bone marrow stem cells are involved in the functional reconstruction of the injured endometrium. OBJECTIVE:To discuss whether bone marrow mesenchymal stem cells can differentiate into endometrial epithelial cells in vitro. METHODS:Passage 2 bone marrow mesenchymal stem cells and endometrial stromal cells were collected and subjected to different treatments: bone marrow mesenchymal stem cells were cultured alone in the DMEM/F12 medium containing 2% fetal bovine serum or in the DMEM/F12 medium containing 2% fetal bovine serum, 10^-7 mol/L β-estradiol and 10 μg/L epidermal growth factor as groups 1 and 2, respectively; bone marrow mesenchymal stem cells co-cultured with endometrial stromal cells by Transwell chamber were cultured in the DMEM/F12 medium containing 2% fetal bovine serum or in the DMEM/F12 medium containing 2% fetal bovine serum, 10^-7 mol/L β-estradiol and 10 μg/L epidermal growth factor as groups 3 and 4, respectively. After 5 days culture, bone marrow mesenchymal stem cells at the bottom of the culture plate were collected to detect expressions of epithelial cell markers, such as CK7, CK18, CK1 and EMA by RT-PCR technology, and to determine keratin expression using immunofluorescence assay. Besides, expressions of these epithelial cell markers in the group 3 were detected using RT-PCR at 1, 3, 5 and 7 days of culture, respectively. RESULTS AND CONCLUSION:mRNA expression of CK7 showed a significant successive rise in the groups 1, 2, 3, 4 and it was highest in the group 4. mRNA expressions of CK18 and CKl9 in the later three groups had no significant differences, but all significantly higher than those in the group 1. Compared with the groups 1 and 3, mRNA expression of EMA in the groups 2, 4 were significantly higher, but no significant differences existed between groups. Expression of keratin was strongly positive in the group 4, weakly positive in the group 3 and negative in the groups 1, 2, respectively. Furthermore, with the increase of culture time, mRNA expression of CK7 exhibited a constant increase, which was significantly higher at 5 and 7 days than at 1 and 3 days; but there were no significant differences in expressions of CKl9, CKl8 and EMA at different time points. These results show that bone marrow mesenchymal stem cells can differentiate into endometrial epithelial cells in vitro under certain conditions. Moreover, it can remarkably promote the endometrial differentiation under the combined effects of some exogenous and endogenous factors.