内外源性结缔组织生长因子对肾小管上皮细胞胶原合成的比较研究

目的：探讨内外源性结缔组织生长因子（CTGF）对人肾小管上皮细胞（HK2）胶原合成的作用。方法：将HK2细胞分为5组：（1）对照组；（2）TGF-β₁ 5 μg/L刺激组；（3）CTGF 5 μg/L刺激组；（4）TGF-β₁ 5 μg/L刺激＋CTGF反义ODN 3 mmol/L干预组；（5）TGF-β₁ 5 μg/L刺激＋CTGF正义ODN 3 mmol/L干预组。采用 RT-PCR 和Western blotting检测胶原Iα₁（Col Iα₁）、胶原IVα₁（Col IVα₁） mRNA水平和蛋白水平表达。 结果：TGF-β₁刺激可使HK2细胞Col Iα₁、Col IVα₁ mRNA和蛋白表达显著升高，而CTGF刺激则无此作用，CTGF反义ODN可拮抗TGF-β₁刺激引起Col Iα₁、Col IVα₁ mRNA和蛋白表达升高，正义ODN无拮抗作用。 结论：内源性CTGF介导了TGF-β₁刺激引起的HK2细胞胶原合成，外源性CTGF对HK2细胞胶原合成无影响。     

转化生长因子β1抑制人肾小管上皮细胞的增殖

背景：慢性肾衰竭进展过程中的一个重要病理改变是炎症和纤维化,主要包括肾小球和肾小管的炎症和纤维化。目前大多数研究主要集中于肾小球,对于肾小管病变的研究相对较少。但实际上部分疾病的肾小管病变出现在肾小球病变之前,其对于疾病预后更具有指导意义。 目的：观察转化生长因子β1对人类肾小管上皮细胞HK-2增殖的影响,探索转化生长因子β1在肾小管炎症和纤维化方面的作用。 方法：将传代培养的HK-2细胞分成空白对照组和转化生长因子β1作用组,分别使用DMEM/F12培养液,以及含转化生长因子β1(2,5,10 μg/L)的DMEM/F12培养液培养,在倒置显微镜下观察各组细胞形态的改变,并使用MTT法检测细胞增殖情况。 结果与结论：转化生长因子β1能显著抑制人肾小管上皮细胞的增殖,并促使细胞向纤维样改变,与空白对照组相比差异有显著性意义(P < 0.05),其抑制增殖作用并不随转化生长因子β1质量浓度的增大而显著增强,作用时间可持续至72 h。结果可见转化生长因子β1能够抑制人肾小管上皮细胞的增殖,并具有促进肾间质纤维化的作用。     

不同分子量尿毒血清组分对人肾小管上皮细胞CTGF基因和蛋白表达的影响

目的：探讨不同分子量尿毒血清组分对人肾小管上皮细胞结缔组织生长因子（CTGF）基因和蛋白表达的影响。方法:无菌条件下收集40份尿毒症病人血清和20例正常人血清，应用Centricon Plus 20 Centrifugal Filter Devices将尿毒血清分离成分子量 >10 000 D，5 000-10 000 D，<5 000 D 3个组分。应用Western blotting方法检测CTGF的蛋白表达，RT-PCR方法检测CTGF mRNA表达。结果:2.5%-20%浓度尿毒血清组CTGF基因表达均明显高于正常对照组，以10%尿毒血清组最高；分子量 <5 000 D尿毒血清组CTGF基因表达与正常对照组差异无显著，而分子量 5 000-10 000 D和 >10 000 D尿毒血清组CTGF基因表达均高于正常对照组，以分子量 >10 000 D尿毒血清组最高。不同浓度尿毒血清组CTGF蛋白表达均高于正常对照组，且有随着尿毒血清浓度的升高而增高，在不同分子量尿毒血清组中，以分子量 >10 000 D组增高最为显著。结论：尿毒症毒素通过影响人肾小管上皮细胞致纤维化细胞因子CTGF基因和蛋白表达从而在人肾小管-间质纤维化中起重要作用，而以分子量大于 10 000 D的尿毒症毒素在其中起主要作用。     

结缔组织生长因子在人及大鼠肝纤维化组织中表达增强

目的观察结缔组织生长因子(CTGF)在人及大鼠肝纤维化组织中的表达。方法雄性SD大鼠32只,皮下注射CCl4后1、4、8周收集肝组织标本;44例人肝组织,其中包括12例正常肝组织、32例慢性病毒性肝炎和肝硬化组织。用免疫组化方法检测CTGF的表达及分布。结果CTGF主要表达于大鼠肝星状细胞及肝细胞胞质中。注射CCl4后,大鼠肝组织中CTGF呈时间依赖性表达增强(P<0.01或P<0.05)。CTGF在人肝纤维化组织中的表达与大鼠相类似,表达水平显著高于正常人(P<0.01)。结论CTGF作为一种促纤维化因子,其过表达可促进肝星状细胞的增殖活化,促进细胞外基质的形成,从而促进肝纤维化的发生、发展。     

慢性心力衰竭大鼠肾组织中血小板源性生长因子及结缔组织生长因子的表达

目的:探讨血小板源性生长因子BB(PDGF-BB)及结缔组织生长因子(CTGF)在慢性心力衰竭大鼠肾组织的表达及意义。方法:采用肾上腹主动脉缩窄法制作Wistar大鼠慢性心力衰竭模型,随机分为假手术组,心衰10 d、20 d、30 d组。观察及比较各组大鼠的血流动力学数值;Masson染色方法观察大鼠慢性心衰时肾组织结构变化;免疫组织化学方法检测各组大鼠肾组织的PDGF-BB及CTGF的表达部位;免疫印迹半定量检测各组大鼠肾组织的PDGF-BB、CTGF的表达水平。结果:心衰模型各组大鼠PDGF-BB、CTGF的蛋白表达均较假手术组高,且随心衰程度的加重而表达升高。结论:慢性心衰可引起肾间质纤维化,其发生发展与心衰的严重程度密切相关。     

百令对慢性肾衰竭模型大鼠肾脏保护和肾结缔组织生长因子表达的影响

目的 观察百令对5/6肾切除大鼠的肾脏保护作用及对肾结缔组织生长因子(CTGF)表达的影响,探讨其延缓肾衰竭进展及抗纤维化的相关机制. 方法 50只SD大鼠随机取8只为假手术组,其余行5/6肾切除术.根据术后3周血肌酐(Scr)值分为模型组、天然虫草组(2.0 g·kg-1·d-1)、百令治疗组(2.0 g·kg-1·d-1)和百令高剂量组(3.0 g·kg-1·d-1).术后4周给药.治疗1个月后检测Scr、尿素氮(BUN)浓度;光镜下观察肾脏病理改变,免疫组化方法检测肾组织CTGF、α平滑肌肌动蛋白(α-SMA)的表达水平,采用图像分析系统进行定量分析. 结果 治疗后模型组大鼠Scr、BUN明显高于假手术组(P<0.01),肾小球与肾小管间质均有明显病理改变,CTGF、α-SMA的表达明显上调;而药物治疗组的Scr、BUN明显低于模型组(P<0.05),肾脏病理损伤减轻,CTGF、α-SMA的表达降低(P<0.05). 结论 百令能改善5/6肾切除大鼠的肾功能,减轻肾脏病理损害,其机制可能与下调肾组织CTGF的表达有关.     

肾小管上皮细胞转分化及逆转的分子机制

肾小管上皮细胞转分化(EMT)过程广泛存在于胚胎发生和肾纤维化过程中,其调节是一个复杂有序的过程,受多种细胞因子和细胞外基质的调节。促纤维化细胞因子如TGF-β1具有诱导EMT的作用,而抗纤维化细胞因子如骨形成蛋白-7(BMP-7)和肝细胞生长因子(HGF)能抑制纤维化过程。     

脂多糖对人近端肾小管上皮细胞IL-18及其受体复合物表达的影响

观察脂多糖(LPS)对体外培养人近端肾小管上皮细胞IL-18及其受体表达的影响,以初步探讨IL-18在肾小管-间质炎症损伤过程中的作用。以不同浓度LPS(0.01、0.1、1、5、10μg/ml)处理人近端肾小管上皮细胞株(HK-2)24 h、36 h及48 h,然后应用RT-PCR及ELISA测定IL-18及其受体α链(IL-18Rα)和β链(IL-18Rβ)mRNA及蛋白的表达水平变化。静息培养的HK-2细胞表达IL-18 m RNA和蛋白、IL-18Rα和IL-18Rβm RNA,LPS促进HK-2细胞IL-18 mRNA和蛋白的表达及IL-18Rα和IL-18RβmRNA的表达,并呈剂量和时间依赖趋势。肾小管上皮细胞可能既是IL-18的产生者,又是IL-18的靶细胞之一,炎症状态下肾小管上皮细胞通过IL-18自分泌方式参与肾小管-间质的炎症损伤过程。     

CTGF在胃癌中的表达及其促进血管生成的机制

目的研究CTGF在人胃癌标本中表达情况及其促进血管生成的机制。方法应用Real Time PCR和免疫组织化学染色检测胃癌标本中CTGF mRNA,VEGF mRNA及其在组织中蛋白表达情况;应用pcDNA3.1质粒上调AGS细胞中CTGF的表达,并用Real Time PCR和Western blot检测VEGF mRNA水平和蛋白水平表达变化;AGS稳定株细胞接种于裸鼠,成瘤后肿瘤组织切片,免疫组化染色。结果与正常组织相比,胃癌组织中CTGF mRNA,VEGF mRNA表达水平均显著增加,免疫组化亦显示CT-GF、VEGF在胃癌的标本中显色比正常对照组织强。统计显示两者mRNA水平及免疫组化表达有相关性（P〈0.05）。转染pcD-NA3.1 CTGF质粒后,AGS细胞中CTGF蛋白的表达上调,Real Time PCR及Western blot检测显示过表达CTGF后,VEGF表达上调。与对照细胞相比,过表达CTGF的AGS的肿瘤形成和生成速度明显加快（P〈0.05）。免疫组化染色显示VEGF的染色明显强于对照组。结论在胃癌中CTGF,VEGF表达明显增加,CTGF可能通过上调VEGF表达促进肿瘤血管生成。     

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.     

胰岛素样生长因子-I对体外培养的肾小管上皮细胞表型转化的作用

目的探讨胰岛素样生长因子-I(IGF-I)对体外培养的肾小管上皮细胞(HKC)表型转化的作用及IGF-I和TGF-β1之间有无协同作用。方法分为4组：(1)无血清对照组；(2)阳性对照组TGF-β1(8μg/L)；(3)IGF-I(1、10、50和250μg/L)组；(4)IGF-I(50μg/L) TGF-β1(8μg/L)和IGF-I(250μg/L) TGF-β1(8μg/L)联合作用组。采用免疫荧光和免疫组化双染色法、流式细胞仪和酶联免疫吸附法观察HKC胞质中抗原角蛋白、钙黏蛋白、波形蛋白和α-SMA的表达，检测细胞培养上清液纤连蛋白和型胶原的浓度。结果IGF-I(50、250μg/L)能诱导HKC细胞表达波形蛋白、α-SMA，失去角蛋白和钙黏蛋白的表达；使α-SMA阳性的HKC细胞数显著高于阴性对照组。联合作用组α-SMA阳性的细胞数明显高于IGF-1或TGF-β1单用组，但无协同作用；IGF-I(10、50、250μg/L)组培养上清液纤连蛋白、I型胶原的浓度明显升高，有剂量和时间依赖性。结论IGF-I能诱导肾小管上皮细胞发生表型转化；IGF-I和TGFβ1对诱导HKC转化无协同作用。     

低氧刺激结缔组织生长因子表达与肾间质纤维化

目的：观察低氧对结缔组织生长因子（CTGF）表达的影响，探讨低氧致肾间质纤维化的机制。方法： 单侧输尿管结扎（UUO）9 d大鼠动物模型，用RT-PCR方法检测肾组织中低氧标记分子-低氧诱导因子（HIF-1α）的mRNA水平，免疫组化方法观察假手术组及模型组肾组织中HIF-1α和CTGF的表达及部位，Western蛋白印迹技术检测肾组织CTGF的蛋白水平。体外实验，正常大鼠肾间质成纤维细胞（NRK-49F）分别置于低氧（1%O2）和正常氧条件下培养6 h，应用RT-PCR和Western蛋白印迹检测CTGF mRNA和蛋白表达水平。结果： 对照组肾组织未能检测到HIF-1α mRNA和HIF-1α蛋白表达；模型组肾组织有高水平HIF-1α mRNA，并出现HIF-1α蛋白表达，主要分布在小管-间质细胞；CTGF蛋白与HIF-1α蛋白表达部位及程度一致；低氧（1% O2）培养刺激NRK-49F细胞表达CTGF mRNA和蛋白。结论： 低氧刺激的CTGF的表达增加与肾间质纤维化的发生有关。     

结缔组织生长因子促进肾小球系膜细胞合成RANTES部分依赖于p42/44 MAPK

检测结缔组织生长因子(CTGF)是否诱导肾小球系膜细胞分泌正常T细胞表达分泌的活化调节因子(RANTES),并探讨其作用机制。应用CTGF刺激静息的培养大鼠肾小球系膜细胞,在刺激后不同时间点应用RT-PCR方法测定RANTES的mRNA表达,应用酶联免疫吸附试验(ELISA)测定上清液中RANTES。应用趋化试验测定上清液对单核细胞(THP-1)的趋化作用。应用Westernblot测定CTGF对丝裂原激活的蛋白激酶(p42/44MAPK)磷酸化的作用。应用磷酸化p42/44MAPK抑制剂PD98059预处理,观察CTGF对上清液中RANTES分泌的影响。结果显示,应用CTGF(100ng/ml)刺激后,系膜细胞的RANTES的mRNA表达上升,上清液中RANTES分泌量增加。RANTES抗体可部分阻止上清液对单核细胞的趋化作用。CTGF诱导p42/p44MAPK磷酸化,而PD98059可抑制这一作用,并部分抑制CTGF诱导的上清液中RANTES的分泌。研究表明,CTGF可引起系膜细胞分泌RANTES,其作用机制部分依赖于p42/p44MAPK的磷酸化。     

结缔组织生长因子在肾间质纤维化中的表达及其调控

CTGF, a member of the CCN family of immediate early genes, is a recently discovered profibrotic growth factor, which is involved in many pathophysiologic procedures. CTGF acts as a downstreame ffector of TGF-β acting on interstitial ceils to enhance the progression of fibrotic renal diseases. It has been shown that CTGF gene expression can be induced or blocked by some kinds of cytokine and drugs. It is an interesting candidate target for future intervention strategies of renal interstitial fibrosis.     

结缔组织生长因子在慢性肝病诊断中的应用研究

探讨结缔组织生长因子(CTGF)在慢性肝病诊断中的应用价值。运用ELISA方法检测198例研究对象,观察血清CTGF水平的变化,分析CTGF水平与临床特征及实验室指标的相关性;运用实时荧光定量RT-PCR方法检测组织中CT-GF mRNA的表达量,比较各组间表达量的变化。乙肝后重度肝纤维化组、肝硬化组、原发性肝细胞癌(HCC)组的血清CTGF水平均显著高于正常对照组,且具有统计学意义(P<0.05);血清CTGF水平与部分临床实验室特征存在相关性,在区分早晚期肝纤维化上具有诊断提示作用;癌旁组织的CTGF mRNA相对表达量显著高于正常对照和癌组织的表达量且具有统计学差异(P<0.05)。血清CTGF水平与肝纤维化、肝硬化及肝癌的发生发展关系密切,有望成为一个新的无创性肝纤维化检测诊断指标,为临床诊断提供依据。     

炔丙基甘氨酸增加高肺血流大鼠肺动脉结缔组织生长因子的表达

目的 探讨硫化氢(H2S)生成酶抑制剂炔丙基甘氨酸(PPG)对高肺血流大鼠肺动脉结缔组织生长因子(CTGF)表达的影响.方法 将32只雄性SD大鼠随机分为分流组、分流 炔丙基甘氨酸(PPG)组、假手术组和假手术 PPG组,每组8只.在大鼠高肺血流动物模型上,观察肺组织H2S含量、血浆ET-1含量、肺组织ET-1 mRNA的表达和肺动脉CTGF蛋白表达的变化.结果 分流4周后,肺组织H2S含量、血浆ET-1含量、肺组织ET-1 mRNA表达及肺动脉CTGF表达均明显升高(P<0.01);应用PPG干预后,分流 PPG组大鼠H2S含量明显降低;血浆ET-1含量、肺组织ET-1 mRNA的表达及肺动脉CTGF蛋白表达比分流组明显增加(P<0.05).结论 内源性H2S可能通过降低血管活性肽ET-1及CTGF在肺组织的表达参与对高肺血流时肺循环结构与功能的调节.     

糖基化终产物对大鼠肾系膜细胞结缔组织生长因子作用的研究

目的：探讨糖基化终产物（AGEs）对大鼠肾系膜细胞结缔组织生长因子(CTGF) mRNA表达及细胞外基质（ECM）合成的影响。方法： 在培养的大鼠肾系膜细胞中，分别加入不同浓度的糖化牛血清白蛋白(AGE-BSA)及牛血清白蛋白(BSA)进行刺激，ELISA法检测培养上清中的纤连蛋白（FN）及Ⅳ型胶原（ColⅣ）含量，RT-PCR检测细胞CTGF mRNA表达。结果： 与加入BSA组比较，AGE-BSA组CTGF mRNA表达明显增强（P<0.01），上清中FN及ColⅣ合成增加（P<0.01）， 与CTGF mRNA表达量之间呈正相关（r=0.83）。 结论： AGEs能明显诱导大鼠肾系膜细胞CTGF mRNA的表达，提示AGEs可能通过上调CTGF mRNA的表达引起ECM积聚。     

Epithelial and connective tissue cell CTGF/CCN2 expression in gingival fibrosis

Gingival overgrowth is a side effect of certain medications and occurs in non-drug-induced forms either as inherited (human gingival fibromatosis) or idiopathic gingival overgrowth. The most fibrotic drug-induced lesions develop in response to therapy with phenytoin; the least fibrotic lesions are caused by cyclosporin A; and intermediate fibrosis occurs in nifedipine-induced gingival overgrowth. Connective tissue growth factor (CTGF/CCN2) expression is positively related to the degree of fibrosis in these tissues. The present study has investigated the hypothesis that CTGF/CCN2 is expressed in human gingival fibromatosis tissues and contributes to this form of non-drug-induced gingival overgrowth. Histopathology/immunohistochemistry studies showed that human gingival fibromatosis lesions are highly fibrotic, similar to phenytoin-induced lesions. Connective tissue CTGF/CCN2 levels were equivalent to the expression in phenytoin-induced gingival overgrowth. The additional novel observation was made that CTGF/CCN2 is highly expressed in the epithelium of fibrotic gingival tissues. This finding was confirmed by in situ hybridization. Real-time polymerase chain reaction (PCR) analyses of RNA extracted from drug-induced gingival overgrowth tissues for CTGF/CCN2 were fully consistent with these findings. Finally, normal primary gingival epithelial cell cultures were analysed for basal and transforming growth factor beta1 (TGF-beta1) or lysophosphatidic acid-stimulated CTGF/CCN2 expression at protein and RNA levels. These data indicate that fibrotic human gingival tissues express CTGF/CCN2 in both the epithelium and connective tissues; that cultured gingival epithelial cells express CTGF/CCN2; and that lysophosphatidic acid further stimulates CTGF/CCN2 expression. These findings suggest that interactions between epithelial and connective tissues could contribute to gingival fibrosis.     

Effects of parathyroid hormone on renal tubular calcium and phosphate handling

Central to the maintenance of calcium homeostasis is the regulated reabsorption of calcium along the nephron. To this end, parathyroid hormone (PTH) is released from the parathyroid gland in response to lowered plasma calcium levels. This hormone acts through the PTH 1 receptor along the nephron to increase urinary phosphate excretion and decrease urinary calcium excretion. In the proximal tubule, PTH inhibits phosphate reabsorption by reducing the abundance of sodium phosphate cotransporters in the apical membrane. PTH likely decreases calcium reabsorption from the proximal tubule, by reducing the reabsorption of sodium, an event necessary for the paracellular movement of calcium across this segment. In the thick ascending limb (TAL), PTH increases calcium permeability and may increase the electrical driving force thereby increasing calcium reabsorption in the TAL. Finally, in the distal convolution, PTH acts to increase transcellular calcium reabsorption by increasing the activity and abundance of the apically expressed calcium channel TRPV5.     

Inhibition of connective tissue growth factor (CTGF/CCN2) in gallbladder cancer cells leads to decreased growth in vitro

Gallbladder cancer (GBC) is an aggressive neoplasm associated with late diagnosis, unsatisfactory treatment and poor prognosis. Previous work showed that connective tissue growth factor (CTGF) expression is increased in this malignancy. This matricellular protein plays an important role in various cellular processes and its involvement in the tumorigenesis of several human cancers has been demonstrated. However, the precise function of CTGF expression in cancer cells is yet to be determined. The aim of this study was to evaluate the CTGF expression in gallbladder cancer cell lines, and its effect on cell viability, colony formation and in vitro cell migration. CTGF expression was evaluated in seven GBC cell lines by Western blot assay. Endogenous CTGF expression was downregulated by lentiviral shRNA directed against CTGF mRNA in G‐415 cells, and the effects on cell viability, anchorage‐independent growth and migration was assessed by comparing them to scrambled vector‐transfected cells. Knockdown of CTGF resulted in significant reduction in cell viability, colony formation and anchorage‐independent growth (P < 0.05). An increased p27 expression was observed in G‐415 cells with loss of CTGF function. Our results suggest that high expression of this protein in gallbladder cancer may confer a growth advantage for neoplastic cells.