结缔组织生长因子对人肾小管上皮细胞株生物学特性的影响

目的:观察重组人结缔组织生长因子(rhCTGF)对人肾小管上皮细胞株(HK-2)的作用.方法:将体外培养的人肾小管上皮细胞分为三组:对照组、rhCTGF 5.0 ng/ml, rhCTGF 10.0 ng/ml.应用MTT法检测CTGF对HK-2增殖的影响;倒置显微镜观察细胞形态学的变化;间接酶标免疫组织化学方法检测E-钙粘蛋白(E-Cadherin),α-平滑肌肌动蛋白(α-SMA)的表达;流式细胞术检测α-SMA阳性的HK-2细胞百分数.结果:在一定的浓度范围内,CTGF能促进HK-2细胞的增殖, CTGF促使HK-2细胞由椭圆形转变为梭形状,可下调E-Cadherin,上调α-SMA, 流式细胞测得三组细胞阳性百分率依次为1.54%,10.24%,25.8%(P＜0.05).结论:CTGF在体外促进HK-2转分化的同时促进HK-2的生长.     

肝细胞生长因子对高糖及结缔组织生长因子培养的肾小管上皮细胞纤维化的影响

目的：探讨肝细胞生长因子（HGF）对高糖及结缔组织生长因子（CTGF）诱导肾小管上皮细胞（HKC）纤维化的影响.方法：体外培养HKC,分别在高糖及CTGF环境下加入不同浓度人重组肝细胞生长因子（rhHGF）,以RT-PCR检测转化生长因子β1（TGF-β1）、CTGF、以及纤维化指标Ⅳ型胶原（COL4A1）、纤连蛋白（FN）、α平滑肌肌动蛋白（α-SMA）等的基因表达.结果：高糖及CTGF刺激下,细胞因子和纤维化指标表达均不同程度增加,其中,CTGF作用下,COL4A1表达明显低于高糖组（P＜0.01）.高糖及CTGF环境下加入rhHGF后,纤维化指标显著降低（P＜0.01）,其中高糖＋rhHGF组,CTGF表达减少,TGF-β1表达无明显改变（P＞0.05）.结论：HGF可通过抑制TGF-β下游因子CTGF的表达,发挥抗肾小管上皮细胞纤维化作用,但CTGF并不是其惟一的阻断途径.     

外源性结缔组织生长因子对人肾小管上皮细胞转分化及细胞外基质合成的作用

目的:探讨外源性结缔组织生长因子(CTGF)在人肾小管上皮细胞转分化及细胞外基质合成中的作用.方法:将体外培养的人肾小管上皮细胞HK2分为三组:对照组;CT-GF小剂量组(终浓度为2.5 μg/L);CTGF大剂量组(终浓度为20 μg/L).用倒置显微镜观察细胞形态学变化;噻唑蓝(MTr)法检测细胞增殖活性;RT-PCR检测HK2细胞E-钙黏蛋白(E-cadherin),α-平滑肌肌动蛋白(α-SMA),纤连蛋白(FN)和胶原ⅠαmRNA水平的变化;免疫组织化学方法观察HK2细胞FN和胶原Ⅰ的表达.结果:CTGF刺激使HK2细胞由椭圆形变为梭形,同时促进HK2细胞增殖.不同浓度的CTGF作用于HK2细胞48 h后,α-SMA和FN mRNA水平显著升高(P＜0.05),E-钙黏蛋白mRNA的表达显著下降(P＜0.05);大剂量CTGF刺激HK2细胞48 h后胶原ⅠαmRNA水平显著升高(P＜0.05).小剂量CTGF组HK2细胞胞质FN表达水平显著增加(P＜0.05),大剂量CTGF组HK2细胞胞质表达FN和胶原Ⅰ均显著增加(P＜0.05).结论:CTGF在体外能够诱导人肾小管上皮细胞转分化,并促进FN的合成,大剂量的CTGF可以增加其胶原Ⅰ的合成.     

IGF-Ⅰ对人肾小管上皮细胞转分化相关基因表达的影响

目的:探讨胰岛素样生长因子-Ⅰ(IGF-Ⅰ)在人肾小管上皮细胞转分化中的作用。方法:将体外培养的人肾小管上皮细胞(HK2)分为对照组和IGF-Ⅰ组:培养液中加入IGF-Ⅰ,终浓度分别为25、50、100、200ng/ml。倒置显微镜观察细胞形态变化。用逆转录-聚合酶链反应(RT-PCR)技术测定HK2细胞E-钙黏蛋白、角蛋白、α-平滑肌肌动蛋白(α-SMA)、波形蛋白和纤连蛋白(FN)mRNA水平的变化。结果:IGF-Ⅰ刺激使HK2细胞形态由椭圆变为梭形。不同浓度的IGF-Ⅰ作用于HK2细胞48h后E-钙黏蛋白和角蛋白mRNA的表达显著下降(P<0.05),α-SMA、波形蛋白和FNmRNA水平显著升高(P<0.01),且呈剂量依赖性。结论:IGF-Ⅰ在体外能刺激人肾小管上皮细胞向肌成纤维细胞(MyoF)转分化,并促进其合成细胞外基质(ECM)。     

脂氧素A4拮抗CTGF所致的人肾小管上皮细胞转分化

目的:探讨脂氧素A4(LXA4)对结缔组织生长因子(CTGF)诱导的肾小管上皮细胞HK2转分化的影响.方法:在体外培养的人肾小管上皮细胞(HK2细胞)中,加入CTGF和LXA4刺激48 h后,用倒置显微镜观察细胞形态学变化,应用RT-PCR、Western blot方法测定上皮细胞E钙黏蛋白和α-平滑肌肌动蛋白(α-SMA)mRNA与蛋白的表达.结果:CTGF刺激使HK2细胞形态由椭圆形转为梭形,下调E钙黏蛋白mRNA与蛋白表达,上调α-SMA的mRNA与蛋白表达.LXAc能够抑制CTGF所致的上述变化,E钙黏蛋白mRNA与蛋白的相对表达值分别为0.270±0.082和0.827±0.177,分别高于CTGF刺激组的0.067±0.015(P<0.05)和0.257±0.221(P<0.05);α-SMA的mRNA与蛋白表达的相对表达值分别为0.070±0.046和0.023±0.023,分别低于CTGF刺激组的0.653±0.256(P<0.05)和0.167±0.050(P<0.05).结论:外源性CTGF能导致HK2细胞转分化为肌成纤维细胞.LXA4可抑制CTGF对HK2细胞的转分化,这为治疗肾间质纤维化提供了一条新途径.     

结缔组织生长因子反义寡核苷酸抑制TGFβ1诱导人肾小管上皮细胞转分化

目的探讨转化生长因子β-1(TGFβ1)诱导人肾小管上皮-肌成纤维细胞转分化(TEMT)过程中结缔组织生长因子(CTGF)的表达和作用.方法在用MTT比色、荧光分析证明阳离子脂质体(DOTAP)介导CTGF反义寡核苷酸(AS)转染HKC可行的基础上,将培养的HKC分为4组正常对照组(C组);TGFβ1组(T组);TGFβ1加AS组(T+AS组);4、TGFβ1加CTGF错义寡核苷酸组(T+SC组).分组处理96h后,分别采用免疫组化、Western blot和RT-PCR技术检测各组CTGF、α-平滑肌肌动蛋白(α-SMA)的表达,并分析CTGF和α-SMA表达量的相关性.结果C组CTGF和α-SMA表达阴性;T组CTGF和α-SMA表达阳性;T+AS组CTGF和α-SMA表达阳性,但皆显著低于T组(P＜0.01)T+SC组CTGF和α-SMA表达皆和T组无显著差异(P＞0.05).相关分析CTGF和α-SMA在表达量上皆呈较强的线性相关性.结论CTGF的AS能有效地抑制TGFβ1所诱导的TEMT,提示CTGF是TGF β1诱导TEMT所必需的成份.     

Role of Connective Tissue Growth Factor in Extracellular Matrix Degradation in Renal Tubular Epithelial Cells

In order to investigate the effects of connective tissue growth factor (CTGF) antisense oligodeoxynucleotide (ODN) on plasminogen activator inhibitor-1 (PAI-1) expression in renal tubular cells induced by transforming growth factor β1 (TGF-β1) and to explore the role of CTGF in the degradation of renal extracellular matrix (ECM), a human proximal tubular epithelial cell line (HKC) was cultured in vitro. Cationic lipid-mediated CTGF antisense ODN was transfected into HKC. After HKC were stimulated with TGF-β1 (5 μg/L), the mRNA level of PAI-1 was detected by RT-PCR. In-tracellular PAI-1 protein synthesis was assessed by flow cytometry. The secreted PAI-1 in the media was determined by Western blot. The results showed that TGF-β1 could induce tubular CTGF and PAI-1 mRNA expression. The PAI-1 mRNA expression induced by TGF-β1 was significantly inhib-ited by CTGF antisense ODN. CTGF antisense ODN also inhibited intracellular PAI-1 protein syn-thesis and lowered the levels of PAI-1 protein secreted into the media. It was concluded that CTGF might play a crucial role in the degradation of excessive ECM during tubulointerstitial fibrosis, and blocking the biological effect of CTGF may be a novel way in preventing renal fibrosis.     

酸性成纤维细胞生长因子诱导大鼠肾小管上皮细胞转分化的作用及机制

目的　探讨酸性成纤维细胞生长因子 (AcidfibroblastgrowthfactoraFGF)在大鼠肾小管上皮细胞株 (NRK)转分化中的作用 ,为肾小管 间质纤维化的防治提供理论依据。方法　在NRK细胞的培养基内加入不同剂量的重组人aFGF ,并在Ⅰ型胶原处理过及未处理的玻璃表面 ,无血清培养 6d。使用透射电镜、免疫细胞化学对肾小管上皮细胞向肌成纤维细胞形态及表型的转变进行评估。结果　不同剂量的aFGF(1、1 0、50ng/ml)处理后的NRK细胞形态和表型发生不同程度的改变 :体积增大、失去尖端 基底极性和微绒毛、细胞延长、具有浸润特征的前后向双末端极性、出现肌动蛋白中间丝结构。免疫组化和Westernblot分析显示加入aFGF后角蛋白表达减少 ,有肌成纤维细胞的特异性标志物α 平滑肌动蛋白 (α SMA)的表达。α SMA阳性细胞的比例与aFGF的浓度呈正相关 ,亲和抗aFGF抗体可消除这种转分化现象。加入aFGF后 ,在玻璃表面α SMA阳性细胞数 (34 4± 0 0 90 ) %较Ⅰ型胶原处理培养表面α SMA阳性细胞数 (74 6± 0 1 0 1 ) %有显著差异 (P <0 0 5)。结论　aFGF在促进肾小管上皮细胞向肌成纤维细胞转分化的过程中有重要的意义 ,该过程亦与细胞的生长环境有关 ,提示肾小管上皮细胞的表型转化是肾间质纤维化的重要原因     

针对CTGF的shRNA抑制TGFβ1诱导人肾小管上皮细胞合成胶原

目的研究针对结缔组织生长因子(connective tissue growth factor,CTGF)的短发夹RNA(short hairpin RNA,shRNA)对转化生长因子β1(TGFβ1)诱导人肾小管上皮细胞株(human renal tubular epithelial cell,HKC)合成胶原的抑制作用.方法设计和构建带有U6启动子的能产生针对CTGF的shRNA的RNA干扰表达质粒,转染至受TGF β1刺激的HKC,以RT-pCR和Western blot检测HKC转染前后CTGF表达,以3H脯氨酸掺入法检测总胶原合成量.结果和仅受TGFβ1刺激组相比,转染了RNA干扰表达质粒的受TGFβ1刺激的HKC CTGFmRNA和蛋白表达明显减弱,总胶原合成量下降(P＜0.01).结论针对CTGF的短发夹RNA能明显抑制TGF β1诱导HKC合成胶原.     

针对结缔组织生长因子的siRNA对高糖诱导人肾小管上皮细胞肥大的影响

目的 观测人肾小管上皮细胞转染针对结缔组织生长因子(CTGF)的siRNA后对高糖诱导细胞肥大的影响.方法 细胞分6组培养:正常对照组(培养基含D-葡萄糖1 g/L),等渗对照组(培养基含D-葡萄糖1 g,L、甘露醇3.5 g/L),高糖组(培养基含D-葡萄糖4.5 g/L),高糖+空白对照组(细胞转染空质粒后培养于高糖培养基中),高糖+阴性对照组(细胞转染含无关序列的质粒后培养于高糖培养基中),高糖+干扰组(细胞转染针对CTGF的siRNA表达质粒后培养于高糖培养基中).收集各组培养至24、48、96 h的细胞,以实时PCR检测CTGF mRNA水平;Western blotting检测CTGF蛋白水平;MTT法测定细胞增殖活力;流式细胞仪测定细胞周期分布;考马氏亮蓝法测定细胞总蛋白含量.结果 高糖刺激可上调HK-2细胞的CTGFmRNA及蛋白水平,使停留于G_1期的细胞比例升高,增殖活力受抑制,细胞肥大指标胞内总蛋白含量增加:而通过特异性siRNA抑制CTGF mRNA表达后,细胞的CTGF蛋白表达随时间延长进行性降低.细胞增殖活力增强,更多的细胞由G_1期进入S期,细胞内总蛋白含量降低.结论 证实了CTGF是高糖诱导HK-2细胞肥大的重要介质.针对CTGF的siRNA能明显改善高糖诱导的肾小管上皮细胞肥大,为进一步寻找DN防治的靶点提供了新的实验依据.

Abstract：

Objective To observe the effect of transfection with small interfering RNA (siRNA) targeting connective tissue growth factor (CTGF) on human tubular epithelial hypertrophy induced by high glucose. Methods HK-2 cells were cultured in DMEM/F12 medium containing 1 g/L glucose (normal control group), 4.5 g/L glucose (high glucose group), or 1 g/L glucose + 3.5 g/L mannitol (iso-osmolar control group). The cells were transfected with pGenesil-1, pGenesil/neg, or pGenesil/siRNA-CTGF and then cultured in DMEM/F12 medium containing 4.5 g/L glucose as the high glucose + blank control group, high glucose +negative control group and high glucose+ interference group, respectively. After cell culture for 24, 48 and 96 h, the cells were collected to detect the mRNA and protein levels of CTGF by real-time PCR and Western blotting, respectively. The proliferative activities of the cells were evaluated with MTT assay, and the total cellular protein contents were determined with Bradford method. Flow cytometry was employed to analyzed the cell cycle changes. Results High-glucose significantly up-regulated the CTGF mRNA and protein levels in HK-2 cells. The cell proliferation was inhibited after high-glucose exposure with increased cell percentage in G, phase and total cellular protein content suggesting cellular hypertrophy. Transfection with siRNA targeting CTGF significantly inhibited high glucose-induced up-regulation of CTGF mRNA and protein and promoted the cell proliferation, resulting also increased cells in S phase and lowered total cellular protein contents. Conclusion CTGF is an important mediator of high glucose-induced tubular epithelial hypertrophy, and transfection with siRNA targeting CTGF can alleviate the hypertrophy, suggesting the potential value of CTGF-targeted treatment in the management of diabetic nephropathy.     

组织块法培养人胃成纤维细胞及其结缔组织生长因子的表达

[目的]探索人胃成纤维细胞体外培养的技术方法及其结缔组织生长因子表达情况。[方法]采用组织块贴壁培养法进行人胃成纤维细胞体外培养并传代,倒置相差显微镜下观察成纤维细胞形态,并用免疫细胞化学法检测培养细胞的波形蛋白与角蛋白表达。用RT-PCR法检测人胃成纤维细胞结缔组织生长因子(CTGF)mRNA表达,免疫细胞荧光染色法检测人胃成纤维细胞CTGF蛋白表达情况。[结果]人胃成纤维细胞培养成功传代,表现为长梭形或星形细胞,免疫细胞化学鉴定细胞波形蛋白阳性,角蛋白阴性。RT-PCR法与免疫细胞荧光染色法证实体外培养的人胃纤维细胞表达CTGF。[结论]组织块法培养的人胃成纤维细胞可在体外稳定培养、传代,人胃成纤维细胞能合成CTGF。     

Role of connective growth factor in plasminogen activator inhibitor-1 and fibronectin expression induced by transforming growth factor β1 in renal tubular cells

Background Connective tissue growth factor (CTGF) contributes greatly to renal tubulointerstitial fibrosis, which is the final event leading to end-stage renal failure. This study was designed to investigate the effects of CTGF antisense oligodeoxynucleotides (ODNs) on the expressions of plasminogen activator inhibitor-1 (PAI-1) and fibronectin in renal tubular cells induced by transforming growth factor β1 (TGF-β) in addition to the role of CTGF in the accumulation and degradation of renal extracellular matrix (ECM). Methods A human proximal tubular epithelial cell line (HKC) was cultured in vitro. Cationic lipidmediated CTGF antisense ODNs were transfected into HKC cells. After HKC cells were stimulated with TGF-β1 (5 μg/L), the mRNA levels of PAI-1 and fibronectin were measured by RT-PCR. Intracellular PAI-1 protein synthesis was assessed by flow cytometry. The secreted PAI-1 and fibronectin in the medium were determined by Western blot and ELISA, respectively. Results TGF-β was found to induce tubular CTGF, PAI-1, and fibronectin mRNA expression. PAI-1 and fibronectin mRNA expression induced by TGF-β was significantly inhibited by CTGF antisenes. ODNs CTGF antisense ODNs also inhibited intracellular PAI-1 protein synthesis and lowered the levels of PAI-1 and fibronectin protein secreted into the medium. Conclusions CTGF may play a crucial role in the accumulation and degradation of excessive ECM during tubulointerstitial fibrosis, and transfecting CTGF antisense ODNs may be an effective way to prevent renal fibrosis.     

结缔组织生长因子体外促进人增生性瘢痕成纤维细胞转分化的研究

目的研究结缔组织生长因子(connective tissue growth factor, CTGF)在人增生性瘢痕成纤维细胞转分化中的作用.方法培养人增生性瘢痕成纤维细胞,分别给予不同剂量CTGF刺激(10 ng/ml),以及CTGF ASODN转染,48 h后用Western blot方法比较各组间α-平滑肌肌动蛋白(α-smooth muscle actin,α-SMA)的表达变化.结果刺激48 h后,对照组表达少量α-SMA蛋白;小剂量CTGF刺激组和大剂量CTGF 刺激组作用48 h后,α-SMA表达量均显著增多,且成浓度依赖性变化(P<0.01);而CTGF ASODN转染组α-SMA蛋白表达与对照组比较明显减少(P<0.05).结论 CTGF在体外能促进人增生性瘢痕成纤维细胞向肌成纤维细胞(myofibroblast ,MyoF)的转分化,阻断或者抑制其表达可能将更有效的治疗瘢痕挛缩.     

黄芪注射液对肾小管上皮细胞转分化的影响

目的观察黄芪注射液对转化生长因子β1(TGF-β1)诱导的体外培养的人肾小管上皮细胞(HK-2)转分化(EMT)过程的影响,揭示黄芪注射液治疗肾间质纤维化(RIF)的具体作用机制。方法以正常培养的HK-2细胞为正常组,TGF-β1(8×10-9mg/L)刺激48 h为模型组,TGF-β1(8×10-9mg/L)与黄芪注射液(8×10-6mg/L)共培养48 h为治疗组。倒置相差显微镜下观察细胞形态变化,免疫组化染色法观察细胞内E-钙依赖黏附素(E-cadherin)和a-平滑肌肌动蛋白(a-SMA)的表达变化。结果倒置相差显微镜下观察发现模型组细胞形态经历了由上皮细胞样转变为成纤维细胞样的改变,而治疗组中成纤维细胞数目较模型组减少,并可见大量的上皮样细胞;免疫组化显示模型组细胞中a-SMA的表达较正常组增多,E-cadherin的表达减少,而治疗组细胞中E-cadher-in的表达较模型组增多,a-SMA的表达降低。结论黄芪注射液可在一定程度上抑制由TGF-β1诱导的体外培养HK-2细胞的表型改变,减少细胞内a-SMA的表达,增加E-cadherin的表达,阻断或逆转其EMT的进程。     

BMP-7对油酸诱导的肾小管上皮细胞转分化的预防作用

目的探讨BMP-7对油酸诱导的人肾小管上皮细胞转分化的预防作用。方法应用体外细胞培养技术培养人肾小管上皮细胞株（HK-2细胞）。先用不同浓度BMP-7预处理HK-2细胞,再用400μmol/L油酸刺激HK-2细胞,采用RT-PCR法和ELISA法检测转化生长因子-β1的表达,采用RT-PCR法检测α-平滑肌动蛋白的表达。结果不同浓度BMP-7预处理对静息培养的肾小管上皮细胞TGF-β1和α-SMA的表达无显著影响。而一定浓度BMP-7可以显著下调油酸诱导的肾小管上皮细胞TGF-β1和α-SMA的表达,并下调TGF-β1的分泌。结论BMP-7可以预防油酸诱导的肾小管上皮细胞转分化。     

脂氧素A4抑制结缔组织生长因子诱导的肾小管上皮细胞表达整合素连接激酶

目的:结缔组织生长因子(connective tissue growth factor,CTGF)可诱导人肾小管上皮细胞HK-2表达整合素连接激酶(integrin-linked kinase,ILK),本研究观察脂氧素A4(lipoxinA4,LXA4)是否调节CTGF对合成ILK的作用,并探讨其作用机制。方法:对体外培养的人肾小管上皮细胞(HK-2细胞株),用不同浓度的LXA4预刺激,再加入CTGF共同孵育;或单用CTGF刺激HK-2细胞。应用RT-PCR和Westernblot方法测定ILKmRNA和蛋白表达,应用Westernblot法测定分裂原激活的蛋白激酶(p42/44mitogen-activated protein kinase,p42/44MAPK)(也称为ERK1/2)、磷脂酰肌醇3-激酶(phosphoinositide 3-kinase,PI3-K)。结果:CTGF刺激使HK-2细胞ILKmRNA表达和蛋白合成增加,磷酸化ERK1/2、磷酸化PI3-K的表达增加。LXA4呈剂量依赖性地抑制CTGF所致的上述变化。结论:LXA4可抑制CTGF引起的HK-2细胞表达ILK,其机制依赖于抑制...     

蛋白酪氨酸激酶活性在人肾小管上皮细胞转分化中的作用

目的探讨蛋白酪氨酸激酶(PTKs)活性在人肾小管上皮细胞 (HKC)转分化中的作用.方法将传代的HKC细胞分为:(1)无血清对照组(C);(2)酸性成纤维细胞生长因子(aFGF)组(A);(3)genistein组(G),加入80ng/ml重组人aFGF条件下,分别加入不同浓度的genistein;培养72h.应用免疫组化检测HKC细胞表达α-SMA(α-smoothmuscleactin,α-SMA)的变化;对转分化过程中PTKs的活性用流式细胞仪加以分析.结果 aFGF(A)组加入80ng/ml aFGF后a-平滑肌动蛋白(a-SMA)表达增强,细胞a-SMA阳性率(60.60±2.70)%较对照组(C)(3.35±1.45)%有非常显著性差异(P<0.01).当G4,5组介入genistein浓度48、96μg/ml时,细胞α-SMA阳性率为(3.90±2.09)%,(3.98±1.75)%,较aFGF组(A)明显降低(P<0.01).PTKs的活性随加入aFGF的浓度增加而增高,当aFGF的浓度为20、40、80ng/ml时,分别比对照组(C)PTKs的活性增加16%、17%、24.6%,当介入genistein剂量为6、12、24、48μg/ml时,分别比aFGF组(A)PTKs的活性下降45.6%、53.5%、66%、81.9%,干预因素作用下HKC细胞PTKs活性与genistein剂量呈负相关(r=-0.987,P<0.05).结论 HKC转分化的机制可能与PTKs活性失控有关,genistein在防治肾间质纤维化中具有很好的应用前途.     

重组人结缔组织生长因子(rhCTGF)促进大鼠烫伤创面愈合的实验研究

目的通过结缔组织生长因子(CTGF)的局部应用,观察其对烫伤创面愈合的促进作用。方法大鼠随机分为用药组和对照组,复制深Ⅱ度烫伤模型,每组为自体对照,用药物和基质,烫伤次日起,开始给药并对创面拍照,观察创面结痂时、创面完全愈合时分别取愈合组织做光镜、电镜、细胞周期检测。结果①给药第15天中剂量(30ng)、高剂量(100ng)组受试侧创面相对愈合面积与同组对照侧差异显著(P<0. 05);②创面完全脱痂时取组织,光学显微镜观察并评分, 10ng组受试侧与对照侧相比差异显著(P<0. 05);③电子显微镜观察,各剂量组受试侧纤维排列明显较对照侧更近似于正常皮肤;④流式细胞仪检测结果显示,中剂量组、高剂量组受试侧细胞G1期较对照侧短,并有差异显著性(P<0. 05 )。结论局部应用合适剂量CTGF可促进深Ⅱ度烫伤创面愈合,缩短创面愈合时间。     

脂多糖对人肾小管上皮细胞株（HK-2）增殖和细胞因子表达的影响

目的:观察脂多糖(LPS)对人肾小管上皮细胞株(HK-2)增殖及炎症因子表达的影响.方法:体外培养的人肾小管上皮细胞分为两组:阴性对照组和LPS刺激组(1.0 ng/ml).应用MTT法检测LPS对HK-2增殖的影响;倒置显微镜观察细胞形态学的变化;间接免疫荧光方法检测白细胞介素-1(IL-1)、白细胞介素-10(IL-10)、肿瘤坏死因子(TNF)的表达;采用ELESA方法检测细胞培养上清中IL-1、IL-10、TNF的含量.结果:LPS组能促进HK-2细胞的增殖,促进细胞表达IL-1、IL-10、TNF.结论:LPS在体外促进HK-2增殖,可分泌促纤维化因子抗纤维化的因子.     

Parathyroid hormone-mitogen-activated protein kinase axis exerts fibrogenic effect of connective tissue growth factor on human renal proximal tubular cells

Background Enhanced and prolonged expression of connective tissue growth factor （CTGF） is associated with kidney fibrosis. Parathyroid hormone （PTH） is involved in the genesis of disturbed calcium/phosphate metabolism and ostitis fibrosa in renal failure. PTH activated mitogen-activated protein kinase （MAPK） signaling pathway is present in renal tubular cells. The aim of this study was to identify the mechanism how the signal is transduced to result in extracellular signal-regulated protein kinase （ERK） activation, leading to upregulation of CTGF.Methods The levels of CTGF mRNA and protein in human kidney proximal tubular cells （HK-2） treated with PTH in the presence or absence of the MAPK inhibitor PD98059 were analyzed by quantitative real-time polymerase chain reaction （RT-PCR） and immunoblotting assay. The activation of the CTGF promoter in HK-2 cells was determined by the dual-luciferase assay. The effects of the protein kinase A （PKA） activator 8-Br-cAMP and protein kinase C （PKC） activator phorbol 12-myristate 13-acetate （PMA） on MAPK phosphorylation, and the effects of the PKA inhibitor H89 and PKC inhibitor calphostin C on MAPK phosphorylation and CTGF expression were detected by immunoblotting assay.Results PD98059 inhibited the PTH stimulated expression of CTGF, which strongly suggested that the MAPK signaling pathway plays an important role in the PTH-induced CTGF upregulation in renal tubular cells. A PKA activator as well as PKC activators induced MAPK phosphorylation, and both PKA and PKC inhibitors antagonized PTH-induced MAPK phosphorylation and CTGF expression.Conclusion CTGF expression is upregulated by PTH through a PKC/PKA-ERK-dependent pathway.