腹膜透析液诱导结缔组织生长因子在大鼠腹膜间皮细胞表达

目的 研究应用不同腹膜透析液对大鼠腹膜间皮细胞(RPMCs)结缔组织生长因子(CTGF)合成的影响。方法 分离培养的RPMC分为6组，分别以不同腹膜透析液[1.5% Dextrose(低糖组)、2.5% Dextrose(中糖组)、4.25% Dextrose(高糖组)、7.5% Icodextrin(糊精组) ]进行刺激培养，而无血清DMEM为阴性对照(对照组)， TGF-β1(2.5 ng/ml)为阳性对照(阳性对照组)。刺激培养24 h后，RT-PCR法检测RPMCs的CTGF mRNA、胶原Ⅰ mRNA、α-SMA mRNA表达。Western印迹法检测RPMCs的CTGF、胶原Ⅰ、α-SMA蛋白表达以及培养上清中的CTGF蛋白表达。结果 各组均见CTGF mRNA表达，高糖组、阳性对照组CTGF mRNA 表达水平显著高于中糖组、低糖组及对照组(P < 0.05)；中糖组与糊精组CTGF mRNA 表达亦显著上调(P < 0.05)。各组细胞均检测到CTGF蛋白质表达，为相对分子质量38 000及 25 000的2种亚型，与RT-PCR结果一致。高糖组、阳性对照组CTGF 蛋白表达水平显著高于糊精组、中糖组、低糖组及对照组(P < 0.05)。RPMCs培养上清液中检测出CTGF 38 000亚型的表达，其表达强弱趋势与CTGF在细胞中表达一致。高糖组、阳性对照组胶原I mRNA、蛋白质的表达水平显著高于对照组(P < 0.05)，其余各组间无显著性差异。各组α-SMA mRNA、蛋白质表达未见显著性差异(P > 0.05)。结论 正常培养的RPMCs表达低水平的CTGF。腹膜透析液、尤其是高浓度葡萄糖透析液，能明显上调CTGF表达的水平，这可能是导致长期腹膜透析过程中腹膜结构改变的机制之一。糊精腹膜透析液生物相容性可能优于高浓度葡萄糖透析液。     

Down-regulation of connective tissue growth factor and type I collagen mRNA expression by connective tissue growth factor antisense oligonucleotide during experimental liver fibrosis.

Transforming growth factor (TGF)-beta 1 is a major mediator of liver fibrosis. Connective tissue growth factor (CTGF) mediates TGF-beta 1 pro-fibrogenic effects in vitro, but its in vivo role is unknown. Both TGF-beta 1 and CTGF are overexpressed in hepatic stellate cells during liver fibrosis. We have used antisense oligonucleotides to examine the role of CTGF in carbon tetrachloride-induced liver fibrosis in mice. Mice received carbon tetrachloride together with CTGF or TGF-beta 1 antisense oligonucleotides for 2 weeks (preventive model), or carbon tetrachloride for 2 weeks followed by carbon tetrachloride and oligonucleotides for 2 more weeks (curative model). In both models, CTGF and TGF-beta 1 oligonucleotides decreased by more than 50 percent the mRNA expression of their targets. Type I collagen mRNA was also decreased by about 40 percent in the preventive experiment. Tissue inhibitor of matrix metalloproteinase-1 mRNA expression and fibrotic deposition evaluated by Sirius red staining were not modified in any group. In summary, our results suggest that hepatic stellate cells can be targeted in vivo with oligonucleotides, and that reducing CTGF levels can lead to a decrease in fibrogenesis as shown by the reduction in type I collagen expression. The lack of effect on fibrosis may be due to the persistence of high tissue inhibitor of matrix metalloproteinase-1 expression.     

Adenoviral-mediated gene expression of hepatocyte growth factor prevents postoperative peritoneal adhesion in a rat model

BACKGROUND: Mesothelial cell proliferation and migration play important roles in reducing formation of postoperative peritoneal adhesions. Hepatocyte growth factor (HGF) is a multifunctional cytokine that stimulates proliferation and migration of various cell types, including mesothelial cells. METHODS: We investigated the effect of adenovirus-mediated HGF gene expression on the proliferation and migration of mesothelial cells and evaluated its preventive effects on postoperative formation of peritoneal adhesions. Rat mesothelial cells were isolated and characterized by expression of cytokeratin and vimentin. RESULTS: Immunohistochemical staining showed that these cells expressed c-Met, the receptor for HGF. Adenoviral-mediated HGF gene transfer into mesothelial cells resulted in high expression of HGF and enhanced migration. To evaluate the preventive effects of adenoviral-mediated HGF gene transfer on the formation of postoperative peritoneal adhesion, we employed a rat model of cecum abrasion-induced adhesion formation in which 80% of the rats developed postoperative peritoneal adhesions. Local application of recombinant adenovirus carrying the HGF gene reduced adhesion formation in 16 of 20 control rats compared with 7 of 20 treated rats in this model. CONCLUSIONS: These results suggest that adenoviral-mediated HGF gene transfer may be a novel strategy for preventing postoperative peritoneal adhesions.     

Tubular expression of connective tissue growth factor correlates with interstitial fibrosis in type 2 diabetic nephropathy.

Sir, Connective tissue growth factor (CTGF) is a secreted proteinimplicated in multiple cellular events, and has been focusedon as a player in the development of renal diseases, especiallydiabetic nephropathy [1,2]. Although CTGF expression is localizedin the podocytes in the normal kidney [     

Adrenomedullin inhibits connective tissue growth factor expression, extracellular signal-regulated kinase activation and renal fibrosis

Systemic administration of the potent vasodilating peptide adrenomedullin reduces cardiac and renal fibrosis in hypertensive animals. Here, we investigated the effects of kidney-specific adrenomedullin gene delivery in normotensive rats after unilateral ureteral obstruction, an established model of renal tubulointerstitial fibrosis. Overexpression of exogenous adrenomedullin in the renal interstitium following ureteral obstruction significantly prevented fibrosis and proliferation of tubular and interstitial cells. In this model, there is upregulation of connective tissue growth factor (CTGF) mRNA expression and extracellular signal-regulated kinase (ERK) phosphorylation, and adrenomedullin overexpression suppressed both of these activities without altering the blood pressure. In NRK-49F renal fibroblasts, adrenomedullin reduced transforming growth factor-beta-induced CTGF and fibronectin mRNA upregulation through the cyclic AMP/protein kinase A signaling pathway, and suppressed ERK phosphorylation and cell proliferation. In the kidneys with an obstructed ureter, adrenomedullin receptor gene expression was upregulated along with cyclic AMP production in kidney slices. The latter effect was partially blocked by a neutralizing antibody to adrenomedullin, indicating that an endogenous peptide-receptor system was activated. Our results show that overexpression of exogenous adrenomedullin in the ureteral-obstructed kidney prevents tubulointerstitial fibrosis and cell proliferation through the cyclic AMP-mediated decrease of CTGF induction and ERK phosphorylation.     

结缔组织生长因子在大鼠肾小管间质纤维化中的表达及意义

在一些伴有细胞增殖、细胞外基质（ECM）沉积和小管间质损伤的肾脏疾病，肾间质结缔组织生长因子（CTGF）mRNA表达上调，提示它是调节肾脏纤维化的关键因子，但CTGF在肾小管间质纤维化发生发展中的动态变化规律，及其对肾间质ECM合成和降解的调节机制仍待阐明。     

黄芪当归合剂及依那普利对结缔组织生长因子在肾间质纤维化中表达的比较研究

目的 探讨结缔组织生长因子(CTGF)在肾间质纤维化中的表达及其在依那普利、黄芪当归合剂的肾脏保护作用中的意义。方法 采用单侧输尿管结扎致肾间质纤维化大鼠模型。将大鼠随机分为4组:假手术组、模型组、黄芪当归组、依那普利组。术后第9天处死各组大鼠,经免疫组织化学(组化)、Western蛋白印迹分析方法观察各组CTGF的表达部位及蛋白表达水平。用免疫组化半定量检测各组肾间质的α-平滑肌肌动蛋白(α-SMA)的表达。用天狼星红染色半定量检测以Ⅰ型胶原为主的肾间质胶原成份。Masson染色评定各组肾小管间质损害程度。结果 模型组CTGF、α-SMA、Ⅰ型胶原的表达及肾小管间质损伤指数明显高于假手术组(P<0.01),而黄芪当归组及依那普利组明显低于模型组(P<0.01)。两治疗组间比较,除结缔组织生长因子外(P<0.01),其余指标无显著性差异(P>0.05)。各项指标作相关分析,CTGF与肾小管间质损伤指数(r=0.788,P<0.01)、α-SMA(r=0.940,P<0.01)、Ⅰ型胶原(r=0.820,P<0.01)为正相关关系。结论 黄氏当归合剂及依那普利可能通过下调CTGF而减轻肾间质纤维化。     

Role of connective tissue growth factor in breast implant elastomer capsular formation

Transforming growth factor-beta (TGF-beta) has been demonstrated to be a mediator in scar formation and in multiple fibrotic disorders such as in Dupuytren contractures and in pulmonary fibrosis. Recently, it has been demonstrated that connective tissue growth factor (CTGF) is a downstream mediator of TGF-beta and acts to stimulate wound contraction and fibrosis. The purpose of this study is to assess the role of CTGF in the development of breast implant elastomer capsule formation over time and to evaluate the effects of TGF-beta and CTGF antisense (AS) oligonucleotides on capsule formation. Fifteen Sprague-Dawley rats were randomly assigned to treatment (n = 12) and control (n = 3) groups. Four 2- x 2-cm pockets were created on the dorsum deep to the panniculus carnosus in each rat. A 1- x 1-cm smooth breast implant elastomer was placed. Each rat in the treatment group received 1 ml vehicle, AS-TGF-beta, AS-CTGF, or scramble antisense oligonucleotide (AS-scramble). Control rats received either 1 ml vehicle or 1 ml saline in each pocket. At weeks 1, 3, and 5, four treatment rats and one control rat were randomly selected and killed. Tissue blocks were harvested for determination of CTGF levels using the enzyme-linked immunosorbent assay technique and for hematoxylin and eosin slides to evaluate capsule formation. Levels of CTGF in capsular tissue treated with vehicle or AS-scrambled were similar and progressively increased in tissues on weeks 1, 3, and 5, compared with normal skin. At weeks 1 and 3 after surgery, levels of CTGF were suppressed in capsules treated with AS-CTGF or AS-TGF-beta compared with normal skin and with tissues treated with vehicle or AS-scramble (p = 0.002). At week 5, levels of CTGF were similar to levels in normal skin. Histological analysis revealed reduced capsular formation in samples treated with AS-CTGF or AS-TGF-beta compared with the two other treated sites. In conclusion, a single and local treatment with AS-CTGF or AS-TGF-beta at the time of surgery reduced CTGF levels in tissue and correlated with reduced capsular formation in a rat model. These data suggest a new therapeutic strategy to reduce early capsular formation based on local application of antisense oligonucleotides targeting CTFG and TGF-beta.     

Reduction in connective tissue growth factor by antisense treatment ameliorates renal tubulointerstitial fibrosis

Connective tissue growth factor (CTGF/CCN2) is one of the candidate factors mediating fibrogenic activity of TGF-beta. It was shown previously that the blockade of CTGF by antisense oligonucleotide (ODN) inhibits TGF-beta-induced production of fibronectin and type I collagen in cultured renal fibroblasts. The in vivo contribution of CTGF in renal interstitial fibrosis, however, remains to be clarified. With the use of a hydrodynamics-based gene transfer technique, the effects of CTGF antisense ODN are investigated in rat kidneys with unilateral ureteral obstruction (UUO). FITC-labeled ODN injection via the renal vein showed that the ODN was specifically introduced into the interstitium. At day 7 after UUO, the gene expression of CTGF, fibronectin, fibronectin ED-A, and alpha1(I) collagen in untreated or control ODN-treated obstructed kidneys was prominently upregulated. CTGF antisense ODN treatment, by contrast, markedly attenuated the induction of CTGF, fibronectin, fibronectin ED-A, and alpha1(I) collagen genes, whereas TGF-beta gene upregulation was not affected. The antisense treatment also reduced interstitial deposition of CTGF, fibronectin ED-A, and type I collagen and the interstitial fibrotic areas. The number of myofibroblasts determined by the expression of alpha-smooth muscle actin was significantly decreased as well. Proliferation of tubular and interstitial cells was not altered with the treatment. These findings indicate that CTGF expression in the interstitium plays a crucial role in the progression of interstitial fibrosis but not in the proliferation of tubular and interstitial cells during UUO. CTGF may become a potential therapeutic target against tubulointerstitial fibrosis.     

Keratinocyte regulation of TGF-β and connective tissue growth factor expression: A role in suppression of scar tissue formation

Allogeneic keratinocytes applied to large full-thickness wounds promote healing while suppressing scar tissue formation. This effect may be mediated in part by their effect on the levels of transforming growth factor-betas (TGF-betas) and connective tissue growth factor (CTGF) in the wound and subsequent modulation of fibroblast activity. We have examined the levels of TGF-beta and CTGF produced by keratinocytes and fibroblasts, and the effect of keratinocyte-conditioned medium using monolayer and living skin-equivalent cultures. Keratinocyte monolayers did not release any detectable TGF-beta1, but released moderate levels of TGF-beta2 into culture medium, and stained strongly for TGF-beta1, but only weakly for TGF-beta2. Fibroblasts released large amounts of TGF-beta1, no TGF-beta2, and stained strongly for TGF-beta1. Neither cell type released TGF-beta3, but both stained strongly for TGF-beta3. Keratinocyte-conditioned medium suppressed the levels of TGF-betas and CTGF associated with the fibroblasts compared with fibroblasts incubated in Dulbecco's minimal essential medium and fibroblast-conditioned medium. In living skin equivalents, keratinocytes stained very strongly for TGF-beta1 and CTGF, moderately strongly for TGF-beta3, and only weakly for TGF-beta2. Fibroblasts stained strongly for TGF-beta1 and 3 and CTGF. These observations suggest that keratinocytes may affect the TGF-beta profile in such a way as to suppress the formation of scar tissue.     

Glomerular expression of connective tissue growth factor mRNA in various renal diseases

SUMMARY:   Connective tissue growth factor (CTGF) is a cysteine-rich member of a new family of growth regulators. It is an important factor in the pathogenesis of mesangial matrix accumulation and progressive glomerulosclerosis. The present study was designed to elucidate the role of CTGF in diabetic nephropathy (DN), immunoglobulin A nephropathy (IgA-N), membranous nephropathy (MN), and minimal change nephrotic syndrome (MCNS). We evaluated the expression and localization of CTGF mRNA in surgically excised renal tissue samples from 10 patients with DN, 10 with IgA-N, 10 with MN, 10 with MCNS, and 10 normal human kidney (NHK) tissue samples, by using high-resolution in situ hybridization with digoxigenin-labelled oligonucleotide. To quantify CTGF mRNA expression, we counted all nuclei, and nuclei surrounded by CTGF-positive cytoplasm, in at least 10 randomly selected cross-sections of non-sclerotic glomeruli, and expressed the results as a percentage of total glomerular cells. In all glomeruli, CTGF mRNA was expressed mainly in glomerular intrinsic cells, including glomerular mesangial and epithelial cells and some cells of Bowman's capsule. The percentage of cells positive for CTGF mRNA was significantly higher in DN and IgA-N than in MN, MCNS and NHK. However, there was no significant difference in the percentage of CTGF mRNA-positive cells between DN and IgA-N. Our study indicates that CTGF may play an important role in the development and progression of glomerulosclerosis in DN and IgA-N, which are both accompanied by mesangial matrix expansion and comprise two major causes of end-stage renal failure.     

The expression of platelet-derived growth factor and connective tissue growth factor in different types of abdominal aortic aneurysms

AIM: An atherosclerotic abdominal aortic aneurysms (AAAA) differ from inflammatory abdominal aortic aneurysms (IAAA), which are characterized by a non specific inflammatory reaction leading to considerable aneurysmal wall thickness from the media to adventitia and retroperitoneal fibrosis in the surrounding tissue. Platelet-derived growth factor (PDGF) and its receptor have been localized to specific cell types within atherosclerotic plaques. Human connective tissue growth factor (CTGF) is a cysteine rich polypeptide that has similar structures to PDGF and has been implicated in connective tissue formation. PDGF and CTGF may play a role in the development of aneurysmal walls in both AAAA and IAAA. METHODS: Using in situ hybridization technique with DIG-labeled RNA probes and immunostaining, we investigated CTGF gene expression, and expression of PDGF and its receptor protein, in human aneurysmal walls. RESULTS: Expression of CTGF mRNA was found on vascular smooth muscle cells (VSMC) in specimens from AAAA and IAAA. Strong CTGF expression was localized in VSMC around calcification in AAAA. In IAAA, strong expression of CTGF was observed around inflammatory cells. In the aneurysmal walls of AAAA, PDGF A and B chains were strongly stained on small vessels, and the PDGF beta receptor was also strongly stained on VSMC around calcification. In the aneurysmal wall of IAAA, weak expressions of PDGF A and B chains were observed in endothelial cells of vessel walls around the inflammatory cells, but the intensity of expression was much weaker than that on the vessel walls in AAAA. CONCLUSIONS: Such differences in fibrogenic cytokine expression may be involved in characteristic aneurysmal formation.     

结缔组织生长因子在椎间盘纤维化和退变中的表达和作用

目的研究疼痛椎间盘组织中结缔组织生长因子（connective tissue growth factor, CTGF）的表达及其在椎间盘纤维化和退变中的作用。方法收集腰椎后路融合过程中切除的43个疼痛的病理椎间盘，来自于28例行腰椎后路椎体间融合手术的严重椎间盘源性下腰痛患者；同时收集16个在MRIT2加权像信号强度明显减弱的无腰痛症状的退变椎间盘，取自于6例腰椎管狭窄症和8例多节段腰椎后路融合的患者（年龄44～75岁，平均53．5岁，男女比例为8：6）和8个正常对照椎间盘，来自于4具新鲜尸体标本（22～39岁，平均28岁）的L。和蛉．椎间盘。均行组织学检查并用免疫组化方法检测CTGF在不同椎间盘组织的表达。结果组织学检查发现，疼痛椎间盘组织显示不同程度的慢性血管化炎症反应。纤维环组织失去正常的胶原纤维板层结构，板层结构断裂、紊乱或相互交叉融合，正常的成纤维细胞被软骨细胞替代。髓核显示明显纤维化、血管浸润或形成炎性肉芽组织，软骨细胞被成纤维细胞所替代。免疫组化染色显示CTGF在疼痛椎间盘大量表达，无腰痛症状的退变椎间盘有少量表达，正常对照椎间盘没有表达。结论疼痛的退变椎间盘在组织学上明显不同于无腰痛症状的退变椎间盘。CTGF在疼痛椎间盘的大量表达可能与椎间盘纤维化和退变过程密切相关。     

Recombinant connective tissue growth factor modulates porcine skin fibroblast gene expression

Connective tissue growth factor (CTGF) is a 38 Kda cysteine-rich, heparin-binding peptide that has been implicated in several normal and abnormal physiological processes. CTGF has been shown to be induced by transforming growth factor-beta. Previous studies in our pig model of skin wound healing showed a coordinate expression of transforming growth factor-beta and CTGF during the healing process. To better understand the function of CTGF during wound healing, normal porcine fibroblasts were isolated from skin samples from SPF Yorkshire pigs. At fourth passage the cells were cultured in Dulbecco's modified Eagle's medium supplemented with fetal calf serum and at 80% confluence the medium was replaced with supplemented serum-free medium. After a further 24 hours, cells were treated with 0, 10, 25, 50, 100, and 500 ng/ml of 38 Kda or 16-20 Kda (C-terminal truncated form) recombinant expressed human CTGF for 24 hours or treated with 100 ng/ml for 0, 12, 24, and 48 hours. Subsequently, CTGF effects on cell DNA synthesis and mRNA levels for a subset of relevant molecules were assessed. The results showed that in cells treated with 38 Kda rhCTGF, mRNA levels for types I and III collagen, fibromodulin, and basic fibroblast growth factor were significantly up-regulated, but mRNA levels for HSP47, decorin, biglycan, and versican were not significantly altered. mRNA levels for CTGF were also significantly increased, indicating autoregulation of expression. However, mRNA levels for transforming growth factor-beta, inteleukins 1 and 6, tumor necrosis factor-alpha, and nerve growth factor did not change. Interestingly, mRNA levels for the tissue inhibitors of metalloproteinase-1, -2, -3 and -4 were observed to significantly increase, but in contrast, mRNA levels for matrix metalloproteinases-1, -2, -9 were not significantly altered by exposure of the cells to the 38 Kda form of CTGF. In addition, DNA synthesis was augmented in the presence of 38 Kda rhCTGF. However, the truncated 16-20 Kda form of rhCTGF appeared to have none of these effects on porcine fibroblasts. These results indicate that in order to induce changes in porcine fibroblasts a molecule with an intact C-terminal domain is required, and that CTGF regulates porcine fibroblast extracellular matrix molecule, growth factor, and proteinase inhibitor gene expression without apparently affecting matrix metalloproteinase mRNA levels. These findings suggest that CTGF contributes to the anabolic environment during skin wound healing via selective modulation of fibroblast proliferation and changes to gene expression.     

丝裂原活化蛋白激酶类和蛋白激酶C在转化生长因子β1诱导肾小管细胞结缔组织生长因子表达中的作用

目的了解转化生长因子β1（TGF-β1）诱导肾小管细胞结缔组织生长因子（CTGF）表达的机制，特别是蛋白激酶C（PKC）和丝裂原活化蛋白激酶（MAPK）在CTGF基因表达中的作用及其对Smad磷酸化的影响。方法分别应用PKC抑制剂G06850以及MAPK的3个组成成分ERK、JNK和p38MAPK的抑制剂PD98059、U0126、SP600125和SB203580阻断相应通路，观察其对TGF．131诱导的CTGF表达以及Smad2／Smad3磷酸化的影响。结果TGF-β1（5μg／L）以时间依赖方式诱导HK-2细胞中Smad2／Smad3的磷酸化，从基础值0．87±0．09上升至2h时高峰2．350±0.11。PKC抑制剂G06850（5μmol／L）和ERK抑制剂PD98059（10μmol／L）、U0126（10μmol／L）可部分抑制TGF-β1诱导的CTGF表达，而p38MAPK抑制剂SB203580（20μmol／L）和JNK抑制剂SP600125（10μmol／L）对TGF-β1诱导的CTGF的表达无影响。PKC抑制剂G06850（5μmol／L）可减少TGF-β1诱导的Smad2／Smad3磷酸化，而ERK抑制剂PD98059（10μmol／L）和U0126（10μmol／L）对Smad2／Smad3的磷酸化没有影响。结论在肾小管上皮细胞中，TGF-β1诱导CTGF的表达需要PKC和Ras／MEK／ERK的参与。PKC以Smad依赖的方式参与肾小管上皮细胞中TGF-β1诱导的CTGF的表达，而Ras／MEK／ERK对CTGF表达的调节不依赖于Smads。     

结缔组织生长因子在血吸虫病肝纤维化肝窦毛细血管化形成中的作用

目的通过动态观察结缔组织生长因子(connective tissue growth factor,CTGF)在血吸虫病性肝纤维化鼠肝窦内皮细胞表达水平的时相变化,探讨CTGF、肝窦内皮细胞与肝窦内皮下基底膜形成的关系。方法采用腹部敷贴法感染血吸虫尾蚴建立血吸虫病性肝纤维化模型,模型组和正常对照组均为40只。于45、60、90、120 d取肝组织标本,苏木素-伊红(HE)、Masson染色和透射电镜观察模型病理变化;免疫组织化学技术检测CTGF、ColⅣ和LN在小鼠肝脏组织中的定位、发布,并应用彩色图像分析仪进行半定量分析;Western blot检测CTGF蛋白;逆转录-聚合酶链反应(RT-PCR)检测CTGF mRNA的表达。结果血吸虫病肝纤维化鼠肝窦内皮细胞表达CTGF蛋白阳性或强阳性,肝窦壁LN、ColⅣ表达水平增高,且随着肝纤维化的发展,CTGF和LN、ColⅣ表达逐渐增强,同步可见肝窦内皮下基底膜逐渐增厚;正常对照组呈阴性或低水平表达。图像定量分析两组平均吸光度值、平均灰度值和阳性面积比具有统计学意义(P<0.05)。相关分析CTGF蛋白与LN、ColⅣ水平呈正相关(r=0.7512、0.6417,P<0.01)。结论血吸虫病肝纤维化时小鼠肝窦内皮细胞调控细胞外基质产生,通过CTGF蛋白表达上调,导致ColⅣ、LN分泌增加,参与肝窦内皮下基底膜形成,从而引起肝内微循环障碍。     

结缔组织生长因子在关木通相关肾小管间质肾病肾间质纤维化中的作用

目的 通过观察关木通相关肾小管间质肾病(GMT-TIN)肾小管间质内纤维化相关生长因子表达及细胞外基质(ECM)沉积的特点,探讨其纤维化病变发生与发展的有关环节。方法 22例GMT-TIN患者根据病理特点分为急性组8例、慢性轻型组8例和慢性重型组6例,对其纤维化程度进行半定量分析。应用免疫组化SP法观察肾活检组织标本中,肾小管间质内α-平滑肌肌动蛋白(α-SMA)、纤连蛋白(FN)、IV型胶原、结缔组织生长因子(CTGF)和转化生长因子 β1(TGF-β1)的表达情况。分析上述指标之间以及与纤维化病变之间的相关关系。结果 (1)各组肾小管间质内均检测到高表达的α-SMA、FN和IV型胶原,随病变慢性化加重3者表达均明显增强,并与肾间质纤维化程度正相关(P<0.01)。(2)各组肾间质内均出现CTGF及TGF-β1表达,2者间显著正相关(r=O.771,P<0.0001),但在时相上存在一定差异。(3)肾间质内CTGF表达分别与FN及IV型胶原沉积正相关(r=0.6855和0.5964,P<0.01)、与纤维化病变程度正相关(r=0.4941,P<0.05)。结论(1)GMT-TIN肾间质内CTGF的高表达、CTGF与ECM沉积以及纤维化病变的相关性,提示其在GMT-TIN肾间质纤维化病变中起重要作用。(2)CTGF与TGF-β1的相关关系及2者表达时相的差异,进一步支持CTGF可能作为TGF-β1的下游效应因子在纤维化病变     

The effect of connective tissue growth factor on renal fibrosis and podocyte injury in hypertensive rats

Objective: The aim of this study was to evaluate the roles of podocalyxin (PCX) and connective tissue growth factor (CTGF) in spontaneously hypertensive rats. Methods: Spontaneously hypertensive rats (SHR) and normotensive control Wistar–Kyoto (WKY) rats were divided into groups referred to as SHR 12W, SHR 24W, WKY 12W and WKY 24W. Systolic blood pressure and 24-hour total uric protein were measured every two weeks in the respective groups. CTGF, PCX, alpha-smooth muscle actin (α-SMA) and collagen-III were evaluated via immunohistochemical staining. In addition, CTGF, PCX, and α-SMA gene expression levels were determined by analyzing mRNA levels. Results: More kidney lesions occurred alongside foot processes effacement in SHR 24W rats than in SHR 12W rats. In SHR 12W rats, blood pressure and 24-hour total uric protein level were elevated and continued to increase thereafter. In the SHR 12W and SHR 24W groups, the expression of CTGF, α-SMA and collagen-III was significantly increased. Immunohistochemical staining showed that PCX expression was significantly reduced in the SHR group and CTGF expression was increased. A significant decrease in PCX mRNA and an increase in CTGF mRNA were observed in SHR 24W rats relative to SHR 12W rats. Conclusion: Both the overexpression of CTGF and the loss of podocalyxin reflect renal damage in spontaneously hypertensive rats. CTGF and PCX may be involved in the mechanisms of podocyte injury and apoptosis induced by hypertension.