Gene expression analysis after prenatal tracheal ligation in fetal rat as a model of stimulated lung growth

Purpose

Prenatal tracheal occlusion or ligation (TL) has been proven to accelerate lung growth, but the mechanism of this is poorly understood. To increase understanding of the biological mechanisms involved in growth stimulation after TL in the fetal lung, we performed Global gene expression analysis using microarray technology.

Material and methods

Sprague-Dawley rats underwent surgery on gestational day 19. After a small hysterotomy, the trachea was mobilized and tied. As controls, we used littermates to manipulated fetuses. On day 21, fetuses were removed and lungs harvested. Global gene expression analysis was performed using Affymetrix Platform and the RAE 230 set arrays (Affymetrix Inc, Santa Clara, Calif). For validation of microarray data, we performed real time polymerase chain reaction (PCR) of the most significant upregulated or downregulated genes, combined with immunohistochemical (IHC) analysis of lung sections.

Results

In the group that underwent TL, several growth factors had an increased expression including connective tissue growth factor (CTGF), insulin-like growth factor 1 (IGF-1), and fibroblast growth factor 18 (FGF-18). Some of the genes that were downregulated in the group that underwent TL compared with controls were surfactant protein A (SP-A), apolipoprotein E (Apo-E), and phospholipase group II A2 (plg2a2). These results could be confirmed with real time PCR and IHC studies.

Discussion

Tracheal occlusion or ligation is a well-documented stimulator of fetal lung growth, and the present study provides novel insights into the underlying molecular mechanisms, with increased expression of genes and proteins with growth factor activity. One of these growth factors, CTGF, has never been previously described in this model. Also, decreased levels of genes involved in surfactant metabolism were observed, providing molecular insights into the decreased surfactant production that is known to occur in TL. Increased understanding of the molecular mechanisms that control lung growth may be the key to develop novel therapeutic techniques to stimulate prenatal and/or postnatal lung growth.     

基因芯片研究尿道下裂的基因表达差异

目的筛选出与尿道下裂发病相关的基因。方法尿道下裂病人的尿道或包皮组织,年龄配对的包皮过长患儿组织作为对照,提取组织mRNA,合成双股cDNA并纯化,再逆转录成cRNA,生物素标记的cRNA打成碎片后与人类基因芯片进行杂交,计算机工作站自动扫描并记录芯片上的信号强度,转化为EXCEL数据库,总共分析了22000个基因的表达差异。结果发现一组表达有显著差异的基因,包括CYR61,CTGF,ATF3和GADD45。结论这些表达差异的基因可能参与尿道下裂的发生和发展,为进一步研究关键基因提供了依据。     

腹膜间皮细胞的培养及TGF-β1 CTGF蛋白含量测定

目的建立简便有效的腹膜间皮细胞体外培养鉴定及TGF-β1、CTGF蛋白含量测定方法。方法胰蛋白酶-EDTANa2消化网膜组织培养腹膜间皮细胞;用形态学、免疫组化鉴定细胞。结果分离培养的细胞符合间皮细胞特征;ELISA法测定细胞培养液中TGF-β1、CTGF蛋白含量简便可行。结论胰蛋白酶消化法是一种简单实用的分离腹膜间皮细胞的方法;ELISA法测定细胞培养液中TGF-β1、CTGF蛋白含量,可能成为衡量预防术     

Nephroblastoma overexpressed gene (NOV) expression in rat hepatic stellate cells

Using the expression-profiling method, we identified nephroblastoma overexpressed gene (NOV) mRNA as one member of the mRNA population that was upregulated in cultured activated hepatic stellate cell (HSC). Northern analysis showed that NOV mRNA was increasingly expressed during progressive activation of cultured rat HSCs, and a significant increase was observed in both the carbon tetrachloride-induced and bile duct ligation/scission rat models of liver fibrosis. RT-PCR showed human NOV mRNA was increased in most fibrotic livers compared with normal livers. The expression of NOV protein in fibrotic rat and human livers was predominantly located in areas of ductular proliferation and HSC of the fibrous septa. HSCs stimulated with transforming growth factor beta1 showed increased expression of NOV protein without changing its mRNA levels. Dexamethasone stimulated the expression of NOV mRNA and protein. Furthermore, we demonstrated that bile acids have a modulating effect on the induction of NOV mRNA expression. In conclusion, this study suggests that NOV is expressed during liver fibrogenesis and HSCs may be an important source of hepatic NOV.     

清燥救肺汤对放射性肺损伤干预作用及对细胞生长因子——CTGF、PDGF影响的研究

目的:观察清燥救肺汤对局部中晚期胸部肿瘤放射治疗的肺保护作用及对结缔组织生长因子(CTGF)、血小板源性生长因子(PDGF)在体内水平的影响。方法:将局部中晚期胸部肿瘤放射治疗者随机分为治疗组和对照组。治疗组在放射治疗开始起服用清燥救肺汤连续6个月。放射治疗前后测定血浆CTGF和PDGF,放射治疗15天起开始观察临床症状、高分辨率CT治疗前和治疗后5个月和10个月测定肺弥散功能。结果:治疗组放射治疗后血浆CTGF和PDGF明显低于对照组(P<0.001)。放射治疗开始后5个月和10个月治疗组CO弥散量下降情况较对照组差异有统计学意义(P<0.05)。治疗组急性放射性肺炎和肺纤维化的发生率比对照组显著降低(P<0.05)。结论:清燥救肺汤能抑制放射治疗后血浆CTGF和PDGF的过度释放,降低放射治疗后弥散功能的恶化。     

Pulmonary hypoplasia in the connective tissue growth factor (Ctgf) null mouse.

Connective tissue growth factor (CTGF) is a mediator of growth factor activity, and Ctgf knockouts die at birth from respiratory failure due to skeletal dysplasia. Previous microarray analysis revealed Ctgf down-regulation in the hypoplastic lungs of amyogenic mouse embryos. This study, therefore, examined pulmonary development in Ctgf-/- mouse fetuses to investigate if respiration could also have been impaired by lung abnormalities. The Ctgf-/- lungs were hypoplastic, with reduced cell proliferation and increased apoptosis. PDGF-B, its receptor and IGF-I, were markedly attenuated and the TTF-1 gradient lost. Type II pneumocyte differentiation was perturbed, the cells depicting excessive glycogen retention and diminished lamellar body and nuclear size, though able to synthesize surfactant-associated protein. However, type I pneumocyte differentiation was not affected by Ctgf deletion. Our findings indicate that the absence of Ctgf and/or its protein product, CTGF, may induce pulmonary hypoplasia by both disrupting basic lung developmental processes and restricting thoracic expansion.     

Cyr61、CTGF、NOV、WISP-1基因在肾癌中的表达

目的〓〖HTK〗探讨肾癌组织CCN蛋白中Cyr61、CTGF、NOV和WISP-1 基因的蛋白表达水平及意义。〖HTW〗方法〓〖HTK〗采用Western blot半定量方法检测31例肾癌组织和18例癌旁正常肾组织中Cyr61、CTGF、NOV、WISP-1基因的蛋白表达。 〖HTW〗结果〓〖HTK〗Cyr61、CTGF、NOV、WISP-1蛋白在肾癌组织中的表达水平均低于癌旁正常组织(P<0.05)，其中乳头状肾癌的NOV和WISP-1 表达水平高于透明细胞癌(P<0.05)，G1级肿瘤NOV表达水平高于G2，3肿瘤(P<0.05)。 〖HTW〗结论〓〖HTK〗Cyr61、CTGF、NOV和WISP-1在肾癌中低表达， CCN基因在肾癌的发生和发展中可能起抑制作用。     

肺癌组织中CTGF和WISP-1基因表达的研究

目的研究肺癌中CTGF和WISP-1基因表达与临床病理因素的关系。方法采用RT-PCR和免疫组化染色法对60名肺癌患者的癌组织和癌旁正常肺组织中CTGF和WISP-1表达水平进行测定。结果65%(39/60)的肺癌组织CTGF基因表达水平低于癌旁正常肺组织(t=-1.59,P=0.016);83%(50/60)的肺癌组织WISP-1基因表达水平高于癌旁正常肺组织(t=4.15,P=0.000),此结果得到免疫组化的证实。Pearson相关分析:WISP-1和CTGF基因的表达呈显著负相关(r=-0.299;P=0.020)。多元线性回归分析:肿瘤位置和性别对癌组织CTGF基因表达有重要影响;病理类型、年龄和家族史对WISP-1基因表达有影响。结论CTGF和WISP-1基因中单个基因或两个基因相互作用对肺癌的进展均起重要作用及其与临床病理因素的关系。     

细胞因子在肺纤维化中的信号转导通路

肺纤维化是多种原因引起的异质性疾病,主要病理特点是早期的弥漫性肺泡炎和后期大量成纤维细胞病理性增生及基质胶原进行性积聚并取代正常的肺组织结构。已有充分证据显示TGF-β、CTGF、PDGFI、GF等细胞因子在组织修复和促纤维化进展中有重要作用。1转化生长因子(transforming     

Hepatitis C virus-replicating hepatocytes induce fibrogenic activation of hepatic stellate cells

BACKGROUND & AIMS: The mechanism by which hepatitis C virus induces liver fibrosis remains largely obscure. To characterize the profibrogenic potential of hepatitis C virus, we used the hepatitis C virus replicon cell line Huh-7 5-15, which stably expresses the nonstructural hepatitis C virus genes NS3 through NS5B, and hepatic stellate cells as fibrogenic effector cells. METHODS: Rat and human hepatic stellate cells were incubated with conditioned media from replicon cells, and expression of fibrosis-related genes was quantified by using real-time polymerase chain reaction, protein, and functional assays. Transforming growth factor beta1 activity was determined by bioassay. RESULTS: Hepatitis C virus replicon cells release factors that differentially modulate hepatic stellate cell expression of key genes involved in liver fibrosis in a clearly profibrogenic way, up-regulating procollagen alpha1(I) and procollagen alpha1(III) and down-regulating fibrolytic matrix metalloproteinases. Transforming growth factor beta1 expression and bioactivity were increased severalfold in hepatitis C virus-replicating vs mock-transfected hepatoma cells. However, transforming growth factor beta1 activity was responsible for only 50% of the profibrogenic activity. CONCLUSIONS: Hepatitis C virus nonstructural genes induce an increased expression of transforming growth factor beta1 and other profibrogenic factors in infected hepatocytes. The direct induction of profibrogenic mediators by hepatitis C virus in infected hepatocytes explains the frequent observation of progressive liver fibrosis despite a low level of inflammation and suggests novel targets for antifibrotic therapies in chronic hepatitis C.