沉默结缔组织生长因子对大鼠肝纤维化的影响

目的 研究结缔组织生长因子(CTGF)小干扰RNA(siRNA)在CCl4诱导的大鼠肝纤维化模型中的抗肝纤维化作用及其对肝星状细胞(HSC)激活的影响.方法 雄性SD大鼠24只,随机分成4组.模型组:皮下注射CCl4及经门静脉注射等渗盐水,每3 d 1次,连续6周(给药频率与时间,下同);CTGF siRNA干预组:皮下注射CCl4及经门静脉注射CTGF siRNA ;对照siRNA干预组:皮下注射CCl4及经门静脉注射对照siRNA;正常对照组:经门静脉注射等渗盐水.用HE染色和Sirius red染色评估大鼠肝组织学变化,Western blot检测肝组织CTGF及α平滑肌肌动蛋白(α-SMA)的表达,免疫组织化学染色评估肝组织α-SMA阳性细胞数量.对实验数据用单因素方差分析或Kruskal-Wallis检验分析.结果 模型组及对照siRNA组大鼠肝组织CTGF及α-SMA蛋白表达显著上调,α-SMA染色阳性细胞数量明显增加.与模型组相比,CTGF siRNA组CTGF及α-SMA蛋白表达分别下调95%±2%和86%±11%(F值分别为21.234和12.473,P值均＜0.01);肝组织α-SMA染色阳性细胞数减少76%±9%(F=9.179,P＜0.01);组织学检查显示肝纤维化程度明显减轻.结论 siRNA沉默CTGF基因能显著减轻大鼠实验性肝纤维化,减少活化HSC数量可能是其改善肝纤维化的主要机制之一.     

抗结缔组织生长因子小分子干扰RNA防治大鼠肝纤维化研究

目的探讨经门静脉注射抗结缔组织生长因子(CTGF)小分子干扰RNA(siRNA)是否能在体内抑制大鼠肝CTGF基因表达及防治大鼠肝纤维化。方法雄性SD大鼠24只,均分成4组,模型组皮下注射40%CCl4(3ml/kg)及门静脉注射生理盐水,每3d1次,连续6周;预防组皮下注射CCl4及门静脉注射抗CTGFsiRNA(0.1mg/kg),每3d1次,连续6周;治疗组皮下注射CCl42周,随后再给予抗CTGFsiRNA及CCl44周;对照组门静脉注射生理盐水6周。于最后1次CCl4注射后3d行门静脉测压,并取血及组织标本,检测血清转氨酶、透明质酸(HA)及Ⅲ型前胶原(PⅢNP)浓度,应用RTPCR及Western印迹法检测CTGFmRNA及蛋白质在大鼠肝组织表达,应用HE及Siriusred胶原染色检测肝组织炎症及纤维化,应用偏光扫描对肝组织胶原染色面积进行定量。结果与模型组相比,预防组及治疗组大鼠肝组织CTGFmRNA及蛋白质表达显著下调,肝组织炎症、坏死及纤维化明显减轻,血清转氨酶、HA及PⅢNP浓度显著降低;预防组、模型组和治疗组的肝组织胶原染色面积分别为5.8%±0.8%、12.3%±0.8%和7.2%±0.9%(P<0.01);门静脉压力分别为(14.2±2.3)cmH2O、(20.6±5.8)cmH2O和(15.1±3.6)cmH2O(P<0.05),明显降低。结论经门静脉注射抗CTGFsiRNA能在体内显著抑制大鼠肝CTGF基因表达并能有效防治大鼠肝纤维化,提示抗CTGFsiRNA有潜力成为防治肝纤维化的一种新策略。     

结缔组织生长因子基因表达与大鼠肝纤维化关系初步研究

目的探讨结缔组织生长因子（connective tissue growth factor，CTGF）基因在肝纤维化大鼠肝组织中的表达及其在肝纤维化发展中的作用。方法采用四氯化碳（CCl4）皮下注射制备肝纤维化模型，并于注射后1、4、8周取大鼠肝组织，免疫组化检测CTGF的表达，RT—PCR检测肝组织结缔组织生长因子和I型胶原α2[COL Ⅰ（α2）]基因的转录，并作图像扫描和统计学分析。结果CTGF免疫组化显示正常大鼠肝组织未见明显阳性着色，模型组大鼠注射CCl4 1周后，肝窦周和汇管区细胞出现阳性染色，随着CCl4注射时间的延长，其表达逐渐增强趋势。正常大鼠肝组织COLⅠ（α2）无表达，注射CCl4 1周后有弱表达，注射CCl4 4周后表达增强，8周时达到高峰。CTGF基因的表达与Ⅰ型胶原（α2）的表达呈正相关。结论CTGF作为TGF-β1的下游细胞因子在肝纤维化的发生和发展中可能发挥重要作用。     

瘦素特异性小干扰RNA对实验性肝纤维化的影响

目的 研究针对大鼠瘦素基因的小干扰(si)RNA对肝纤维化的治疗效果.方法 将40只雄性SD大鼠平均分为4组,正常对照组皮下注射橄榄油溶液3 ml/kg,2次/周,共6周;肝纤维化模型组皮下注射60% CCl4 3 ml/kg,2次/周,共6周;siRNA治疗组和阴性对照组均于皮下注射60% CCl4 3 ml/kg,2周后尾静脉分别注射siRNA或阴性对照质粒0.2 mg/kg.每周测体质量1次,根据体质量调整药物用量.设计针对瘦素mRNA的siRNA,并构建其表达载体;用脂质体方法通过尾静脉注射转染入CCl4诱导的肝纤维化大鼠体内,然后分别采用逆转录-聚合酶链反应、免疫组织化学方法检测瘦素与Ⅰ、Ⅲ型胶原在肝脏组织中的表达.免疫组织化学资料采用等级资料秩和检验.PCR结果采用单因素方差分析进行统计学处理,P＜0.05时用SNK法进行多重比较.结果 瘦素mRNA在正常对照组组、肝纤维化模型组、siRNA治疗组和阴性对照组的相对表达量分别为0.75±0.03、2.34±0.14、0.90±0.06、2.31±0.13,各组比较,F=797.64,P=0.000,差异有统计学意义;Ⅰ型胶原mRNA在各组的相对表达量分别为1.10±0.11、2.75±0.13、1.27±0.08、2.77±0.12,各组比较,F=695.71,P=0.000,差异有统计学意义;Ⅲ型胶原mRNA在各组的相对表达量分别为0.62±0.07、1.52±0.09、0.85±0.08、1.51±0.07,各组比较,F=371.57,P=0.000,差异有统计学意义.结论 针对瘦素基因的siRNA对肝纤维化有明显的治疗作用.     

激动素对肝纤维化大鼠肝脏胶原变化的作用研究

目的:观察激动素(kinetin)对肝纤维化大鼠肝脏Ⅰ、Ⅲ型胶原含量的作用。方法:将实验大鼠随机分为3组,模型组用CCl4诱导形成肝纤维化模型;激动素组造模同时给予0.1%激动素溶液5ml·kg-1·d-1;对照组仅给予生理盐水皮下注射,均治疗12周。应用苦味酸天狼猩红偏振光法和图像分析技术对3组中的胶原含量及分布特点进行观察。结果:激动素组Ⅰ型胶原与Ⅲ型胶原含量分别为(2.107±0.833)%和(1.114±0.413)%,分别较模型组(4.473±2.311)%和(1.964±0.854)%显著降低(P<0.01)。结论:激动素能使肝纤维化大鼠肝脏Ⅰ、Ⅲ型胶原含量显著降低。     

沉默结缔组织生长因子对鼠转化生长因子β/Smads信号的影响

目的 研究小干扰RNA(siRNA)沉默结缔组织生长因子(CTGF)对大鼠转化生长因子(TGF)β/Smads信号通路的影响.方法 将化学合成CTGF siRNA转染肝星状细胞(HSC)T6和经门静脉注入CCl4诱导6周的肝纤维化大鼠,设空白及随机siRNA对照,抽提HSC T6及大鼠肝组织总RNA和蛋白质,应用Western blot和RT-PCR检测HSC T6及肝组织CTGF及TGF β1,Smad2、3、7蛋白质和基因表达. 结果与空白对照组相比,siRNA能显著下调HSC T6 CTGF蛋白表达,以48 h最明显,CTGF蛋白表达下调94%±4%(t=46.196,P<0.01),而TGF β1、Smad2,3,7 mRNA表达差异无统计学意义;模型组及对照siRNA组,CCl4诱导的大鼠肝组织CTGF和TGF β1蛋白表达明显上调,与模型组相比,CTGF siRNA组大鼠肝组织CTGF及TGF β1蛋白表达分别下调95%±2%(F=21.234,P<0.01)和74%±8%(F=13.464,P<0.05),但Smad2和Smad7蛋白表达无明显改变. 结论沉默CTGF基因表达对大鼠肝TGF β/Smads信号具有阻抑作用.     

养肝软坚方抗大鼠肝纤维化的实验研究

目的：探讨中药复方养肝软坚方对四氯化碳（CCl4）诱导的实验大鼠肝纤维化的治疗作用。方法：60只雄性SD大鼠随机分为：正常对照组、模型组及治疗组,除正常对照组外所有大鼠均给予皮下注射40%CCl4（每3天1次,共11周）。造模3周后治疗组大鼠给予养肝软坚方10ml.kg-1.d-1,正常对照组及模型组大鼠给予等量生理盐水,1次/d,共8周。实验结束时检测大鼠肝功能、血清透明质酸（HA）、层黏连蛋白（LN）、Ⅲ型前胶原（PCⅢ）和肝脏羟脯氨酸（Hyp）,采用光镜观察肝脏病理组织学改变。结果：养肝软坚方能改善肝纤维化大鼠的肝功能,可显著降低血清HA、LN、PCⅢ水平和肝组织中过高的Hyp,病理组织学观察表明其能显著改善肝纤维化程度。结论：养肝软坚方对CCl4诱导的大鼠具有较好的抗肝纤维化作用。     

抗结缔组织生长因子小干扰RNA对肝星状细胞合成分泌细胞外基质的影响

目的 研究化学合成抗结缔组织生长因子(CTGF)小干扰RNA(siRNA)对肝星状细胞(HSC)CTGF基因表达及合成分泌细胞外基质(ECM)的影响。 方法 将化学合成抗CTGF siRNA以Oligofectamine包裹,转染HSC T6细胞,设空白对照,抽提孵育24、48、72 h细胞总RNA及蛋白质,并收集培养上清液,应用western blot和(或)逆转录聚合酶链反直检测HSC T6细胞CTGF及Ⅰ、Ⅲ型胶原基因表达,应用放射免疫法检测培养上清液中透明质酸及Ⅲ型前胶原含量。 结果 与空白对照相比,转染siRNA的HSC T6细胞CTGF及Ⅰ、Ⅲ型胶原基因表达水平显著下调,培养上清液中透明质酸及Ⅲ型前胶原含量24、48、72h分别降低46％±7％,52％±7％,53％±7％(F=157.45,P=0.0001)和29％±18％,29％±7％,27％±5％(F=10.77,P=0.0079)。 结论 化学合成抗CTGF siRNA能高效抑制HSC CTGF基因表达,显著减少HSC Ⅰ、Ⅲ型胶原及透明质酸等ECM的合成与分泌,抑制效应可持续72 h,提示化学合成CTGF siRNA具有预防及治疗肝纤维化的潜力并具有极好的开发前景。     

反义抑制结缔组织生长因子对实验性肝纤维化的影响

目的观察结缔组织生长因子(CTGF)反义RNA对实验性肝纤维化的影响。方法应用分子生物学技术构建CTGF反义RNA真核表达质粒,经腹腔注射入CCl4诱导的肝纤维化模型大鼠体内;通过RT-PCR、Western blot及免疫组织化学等方法检测CTGF反义RNA基因转染前后CTGF mRNA和蛋白质在肝组织中含量的变化;并通过检测肝组织中Ⅰ、Ⅲ型胶原含量的变化,观察CTGF反义RNA对大鼠肝纤维化的影响。结果转染CTGF反义RNA后,可抑制CTGF mRNA和蛋白质的表达(P<0.01),减少Ⅰ、Ⅲ型胶原的沉积(P<0.01),并在一定程度上促进肝组织的改善(P<0.01)。结论CTGF反义RNA对肝纤维化有一定的治疗作用。     

参芍软肝汤抗大鼠肝纤维化的疗效及其对肝星状细胞活化及凋亡的影响

目的探究参芍软肝汤对于大鼠肝纤维化的作用效果,研究其对肝星状细胞(HSC)调控机制的影响。方法采用皮下注射四氯化碳(CCl4)法诱导大鼠产生肝纤维化,对纤维化大鼠进行参芍软肝汤治疗,定量检测各生化指标,包括白蛋白(ALB)、丙氨酸氨基转移酶(ALT)、层黏连蛋白(LN)、天冬氨酸氨基转移酶(AST)、透明质酸(HA)、Ⅳ-C型胶原(Ⅳ-C)和Ⅲ型前胶原(PC-Ⅲ);采用Real Time-PCR法检测转化生长因子(TGF)-β1和α-平滑肌动蛋白(SMA)mRNA表达水平研究参芍软肝汤对HSC-T6的影响;采用流式细胞术检测参芍软肝汤对HSC-T6凋亡的影响。结果与模型组比较,治疗组血清中ALT、AST、HA、LN、Ⅳ-C、PC-Ⅲ的表达水平明显降低,ALB含量显著上升(P0.05);与正常组比较,药物组明显抑制HSC-T6细胞α-SMA和TGF-β1的mRNA的表达(P0.01);药物组明显促进HSC-T6凋亡水平(P0.001)。结论参芍软肝汤对CCl4诱导的大鼠肝纤维化具有一定的治疗作用,并且参与调控HSC活化及凋亡。     

抗结缔组织生长因子小分子干扰RNA防治大鼠肝纤维化的研究

目的 探讨经腹腔注射抗结缔组织生长因子(CTGF)小分子干扰RNA(siRNA)是否能抑制大鼠体内肝脏CTGF基因表达及防治大鼠肝纤维化.方法 雄性SD大鼠30只,随机分成5组,分别为模型组腹腔注射40%CCl4 (3 mL/kg)及尾静脉注射生理盐水,1次/3 d,连续8周;预防组腹腔注射40%CCl4 及尾静脉注射...     

化学合成经修饰抗TIMP-2小干扰RNA抑制胆总管结扎大鼠肝纤维化形成

目的研究化学合成经修饰抗金属蛋白酶组织抑制剂-2（tissue式分解inhibitor of metalloproleinase-2，TIMP-2）小干扰RNA（small interfering RNA，siRNA）对胆总管结扎大鼠肝纤维化形成的影响。方法30只雄性SD大鼠随机均分成5组：正常组、假手术组、模型组、阴性对照组、治疗组，行胆总管双重结扎和经肠系膜上静脉（superior mesenter vein，SMV）皮下置管手术，2周后给予治疗组0．05mg·kg^-1 siRNA经皮SMV注射，每3天1次。6周后取所有动物肝组织标本，经门静脉测压（portal vein pressure，PVP）和腹主动脉取血。常规HE染色和Van Gieson（VG）胶原染色，检测血清丙氨酸氨基转移酶（alanine aminotransferase，ALT）、天冬氨酸氨基转移酶（aspartate aminotransferase，AST）和肝组织羟脯氨酸（hydroxyproline，Hyp）含量。应用荧光实时定量PCR法检测TIMP-2、I型胶原纤维（collagen type I，COL I）和Ⅲ型胶原纤维（collagentype Ⅲ，COLⅢ）mRNA的表达。应用Western印迹检测TIMP-2蛋白、α-平滑肌肌动蛋白（α-smooth muscle antibody，α-SMA）和结蛋白（Desmin）的表达。结果经抗TIMP-2 siRNA干预后，大鼠肝脏组织学病变减轻，PVP降低，血清ALT和AST水平下降，肝组织Hyp含量减少，且TIMP-2、COL I和COL Ⅲ mRNA的表达显著低于模型组，TIMP-2蛋白的表达也显著降低。同时肝星状细胞（hepatic stellate cells，HSCs）标记物α-SMA和Desmin蛋白的表达均显著低于模型组，尤以α-SMA蛋白表达减少更为明显。结论化学合成经修饰抗TIMP-2 siRNA能够抑制胆总管结扎大鼠肝纤维化形成，有可能成为肝纤维化治疗的新策略。     

Differential expression genes analyzed by cDNA array in the regulation of rat hepatic fibrogenesis.

PURPOSE: To analyze the gene expression pattern in rat hepatic fibrogenesis and further assess the role of some key genes during the pathological process. METHODS: Hepatic fibrosis was induced by intraperitoneal injection of dimethylnitrosamine or carbon tetrachloride (CCl(4)) injection subcutaneously in rats, and identification of the hepatic fibrosis related genes with cDNA microarray was performed. After some key genes up-regulated during the development of hepatic fibrosis were screened and confirmed, their effects on the function of the activated rat hepatic stellate cells (HSC) were assessed using the small interfering RNA (siRNA) technique. RESULTS: Using an Atlas rat cDNA array, a number of differentially expressed genes in fibrotic liver tissues were identified compared with non-diseased control. A total of 15 genes predominantly associated with the mitogen-activated protein kinase (MAPK) signal transduction pathway were upregulated in the fibrotic liver. Immunohistochemical study revealed that the expressions of both extracellular signal-regulated kinases (ERK) and ribosomal protein S6 kinase (RSK), two of the key genes in the MAPK pathway, were remarkably induced, which was closely correlated to that of collagen types I and III during the development of hepatic fibrosis. Transfection of siRNA targeting ERK1 mRNA (siERK1) into HSC led to a 66% and 72% reduction of ERK1 mRNA and protein expression, respectively. Furthermore, siERK1 exerted the inhibition of the proliferation of HSC, accompanied by the induction of HSC apoptosis and reduction of collagen types I and III. In addition, siERK1 abolished the effect of platelet-derived growth factor-BB on the proliferation of HSC. CONCLUSIONS: The present study provided strong evidence for the participation of the MAPK pathway in the pathogenesis of hepatic fibrosis. Selective targeting of ERK1 inhibitors to HSC might present as a novel strategy for the treatment of hepatic fibrosis.     

Taurine inhibits deposition of extracellular matrix in experimental liver fibrosis in rats]

OBJECTIVE: To study the effect of taurine on liver fibrosis and its mechanism. METHODS: Fibrosis was induced by the administration of carbon tertrachloride(CCl4) in rats. Some of the animals were treated with taurine. The rats were killed after 12 weeks of CCl4 treatment. Depositions of type I, III and IV collages, laminin and hyaluronic acid were studied in liver sections by immunohistochemical technique using specific antibody. The hepatic contents of type I, III procollage and tissue inhibitor of metalloproteinase-1(TIMP-1) mRNA were determined by Northern blot hybridization. RESULTS: A significant elevations of hepatic collagen I, III, IV, laminin and hyaluronic acid were observed after 12 weeks of liver injury in animals without taurine treatment, and a definite increase in the amounts of hepatic type I, III procollagen and TIMP-1 mRNA was noted. Taurine prevented increases in type I, III procollagen mRNA expression as well as the accumulation of the collagens, laminin and hyaluronic acid in the liver. CONCLUSION: The data indicate that taurine has a protective effect in CCl4-induced hepatic fibrosis. The results suggest taurine might be of potential value in clinical practice.     

肝纤维化大鼠血小板衍生生长因子受体β亚单位的表达及其与细胞外基质成分的相关性

目的 研究血小板衍生生长因子(PDGF)受体β亚单位在肝纤维化组织中的动态表达及其与细胞外基质成分的相关性。 方法 将动物分为正常对照组和模型组,用C Cl4复制肝纤维化模型,用免疫组化方法动态检测PDGF受体β亚单位、α～平滑肌抗体(α-SMA)、Ⅰ、Ⅲ型胶原在肝纤维化组织中的表达,将免疫组化结果行图像扫描半定量后进行统计学分析并计算其相关性。 结果 随着肝纤维化程度的加重,PDGF受体β亚单位、α—SMA表达逐渐增加,Ⅰ、Ⅲ型胶原的表达也逐步增加。在2周时PDGF受体β亚单位与Ⅰ、Ⅲ型胶原的相关性不明显,但与α-SMA呈显著相关,其相关系数为0.6 2(P<0.05);在4周时其与Ⅰ、Ⅲ型胶原和α—SMA的相关系数分别为0.74、0.60和0.69(P<0.05);在6周时其与Ⅰ、Ⅲ型胶原和α-SMA的相关系数分别为0.83、0.67和0.81(P<0.05)。 结论 PDGF受体β亚单位在肝纤维化的发生发展中起重要作用,抑制PDGF受体β亚单位的表达可望能减少细胞外基质的合成。     

Beneficial effects of pioglitazone on left ventricular hypertrophy in genetically hypertensive rats.

Beneficial effects of thiazolidinediones, peroxisome proliferator-activated receptor gamma (PPARgamma) agonists, on cardiovascular injuries have been reported. However, the effects of these agonists on left ventricular (LV) hypertrophy have not been clarified. To investigate whether pioglitazone improves LV hypertrophy, we used 32-week-old stroke-prone spontaneously hypertensive rats (SHR-SP) that had been treated or not treated with pioglitazone (10 mg/kg/day) for 8 weeks, and Wistar Kyoto rats (WKY). We evaluated LV geometry by echocardiography; myocyte hypertrophy, tissue fibrosis, and appearance of myofibroblasts by histological examination; mRNA expression by real-time polymerase chain reaction (PCR); protein expression by Western blot; activities of matrix metalloproteinase (MMP) by zymography; and production of reactive oxygen species (ROS) by electron spin resonance spectroscopy or thiobarbituric acid reactive substances (TBARS). SHR-SP showed concentric hypertrophy of the LV, but WKY did not. The myocyte diameter, fraction of tissue fibrosis, and number of myofibroblasts were greater in SHR-SP. mRNA expressions of collagen type I and type III, tissue growth factor (TGF)-beta1, and brain natriuretic peptide (BNP); protein expression of connective tissue growth factor (CTGF); activities of MMP2 and MMP9; and ROS were increased in SHR-SP. Pioglitazone did not decrease blood pressure, but partially normalized LV geometry in addition to decreasing myocyte diameter, interstitial fibrosis and number of myofibroblasts; mRNA levels of collagen type I and BNP; MMP2 activity; and protein level of CTGF. However, the mRNA level of collagen type III and TGF-beta1, MMP9 activity, and ROS production were not improved. In conclusion, pioglitazone reversed the concentric LV remodeling independently from blood pressure or oxidative stress in chronic hypertension.     

Effects of extract from Ginkgo biloba on carbon tetrachloride-induced liver injury in rats

AIM: To study the effects of extract from Ginkgo biloba (EGb) containing 22% flavonoid and 5% terpenoid on chronic liver injury and liver fibrosis of rats induced by carbon tetrachloride (CCl4). METHODS: All rats were randomly divided into control group, CCl4-treated group, colchicine-treated group and EGb-protected group. Chronic liver injury was induced in experimental groups by subcutaneous injection of CCl4 and fed with chows premixed with 79.5% corn powder, 20% lard and 0.5% cholesterol (v/v). EGb-protected group was treated with EGb (0.5 g/kg body weight per day) for 7 wk. At the end of wk 8, all the rats were killed. Liver function, liver fibrosis, oxidative stress and expression of transforming growth factorβ1 (TGF-β1), a-smooth muscle actin (α-SMA) and typeⅠcollagens in liver were determined. In addition, pathology changes of liver tissue were observed under light microscope. RESULTS: The levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST) and albumin (Alb) in EGb-protected group were notably improved as compared with the CCL4-treated group (P < 0.01). The contents of serum hyaluronic acid (HA), typeⅢprocollagen (PCⅢ), typeⅣcollagen (CIV) and the expression of hepatic tissue TGF-β1,α-SMA and typeⅠcollagen in EGb-protected group were significantly lower than those in CCL4-treated groups (P < 0.05, P < 0.01). The degrees of liver fibrosis in EGb-protected groups were lower than those in CCL4-treated groups (6.58±1.25 vs 9.52±2.06, P < 0.05). Compared to the CCL4-treated group, the levels of plasma glutathoine peroxidase (Se-GSH-Px), superoxide dismutase (SOD) and malondialdehyde (MDA) were strikingly improved also in EGb-protected group (P < 0.05, P < 0.01). CONCLUSION: EGb resists oxidative stress and thereby reduces chronic liver injury and liver fibrosis in rats with liver injury induced by CCl4