CONSTRUCTING ADENO-ASSOCIATED VIRUS-TGFβ3 AND COMPARING ITS BIOLOGICAL EFFECT ON PROTEOGLYCAN SYNTHESIS IN DEDIFFERENTIATED NUCLEUS PULPOUS CELLS WITH ADENOVIRUS-TGFβ1

Objective To construct adeno-associated virus (AAV) expression system for transforming growth factor β3 (TGFβ3) and detect its biological effect on proteoglycan synthesis of the earlier and later dedifferentiated rabbit lumbar disc nucleus pulpous (NP) cells, which was compared with that of adenovirus (AV) expression system for TGFβ1. Methods TGFβ3 gene was obtained using PCR. Its upstream contained restriction enzyme site Kpn Ⅰ, and its downstream contained restriction enzyme site SalⅠ. Using the restriction enzyme sites of PCR product of TGFβ3 and the corresponding multiple cloning site (MCS) in plasmid AAV, TGFβ3 was subcloned into AAV. The recombinant plasmid AAV-TGFβ3 was transfected into H293 cells with LipofectamineTM 2000, and the expression of TGFβ3 gene was detected using immunofluorescent analysis. After AAV-TGFβ3 virus particle with infectious activity was packaged, TGFβ3 expression in NP cells was detected by immunoblotting, and its biological effect on proteoglycan synthesis was detected by antonopulos method and compared with that of AV-TGFβ1 in the earlier and later dedifferentiated NP cells. Results For the earlier dedifferentiated NP cells, AAV-TGFβ3 slowly and stably enhanced proteoglycan synthesis, but AV-TGFβ1 rapidly and transiently enhanced its synthesis. For the later dedifferentiated NP cells, AAV-TGFβ3 stably enhanced proteoglycan synthesis, but AV-TGFβ1 inhibited its synthesis. Conclusion AAV expression system can mediate TGFβ3 gene to be expressed stably, and AAV-TGFβ3 can enhance proteoglycan synthesis of the earlier and later dedifferentiated NP cells.     

Rhein inhibits transforming growth factor β1 induced plasminogen activator inhibitor-1 in endothelial cells

Objectives To investigate the effect of rhein on endothelial plasminogen activator inhibitor-1 (PAI-1) mRNA expression and protein production induced by transforming growth factor β1 (TGFβ1), and to explore the mechanism of the protective action of rhein on endothelial cells. Methods A human umbilical endothelium derived cell line (ECV-304) from ATCC was used in this study. The PAI-1 mRNA expression and protein synthesis in the endothelial cells were detected by Northern blot and flow cytometry analysis, respectively. The activity of phospho-p44/p42 MAP kinase induced by TGFβ1 was determined by immunoprecipitation analysis and western blot. Results TGFβ1 rapidly increased PAI-1 mRNA expression in the endothelial cells, and this effect lasted at least 24 hours. The upregulation of PAI-1 mRNA expression induced by TGFβ1 in endothelial cells was inhibited by rhein in a dose-dependent manner. In addition, rhein inhibited endothelial PAI-1 protein production. Further study revealed that rhein had a significant inhibitory effect on the activity of phospho-p44/p42 MAP kinase induced by TGFβ1 in human endothelial cells. Conclusions Our results showed that rhein may have a protective effect on the endothelial dysfunction by inhibiting overexpression of PAI-1, indicating a way for the treatment of vascular diseases.     

CONSTRUCTING ADENO-ASSOCIATED VIRUS-TGFp3 AND COMPARING ITS BIOLOGICAL EFFECT ON PROTEOGLYCAN SYNTHESIS IN DEDIFFERENTIATED NUCLEUS PULPOUS CELLS WITH ADENOVIRUS-TGFβ1

Objective To construct adeno-associated virus (AAV) expression system for transforming growth factor β3 (TGFβ3) and detect its biological effect on proteoglycan synthesis of the earlier and later dedifferentiated rabbit lumbar disc nucleus pulpous (NP) cells, which was compared with that of adenovirus (AV) expression system for TGFβ1.Methods TGFβ3 gene was obtained using PCR. Its upstream contained restriction enzyme site Kpn Ⅰ, and its downstream contained restriction enzyme site Sal Ⅰ. Using the restriction enzyme sites of PCR product of TGFβ3 and the corresponding multiple cloning site (MCS) in plasmid AAV, TGFβ3 was subcloned into AAV. The recombinant plas-mid AAV-TGFβ3 was transfected into H293 cells with Lipofectamine(tm) 2000, and the expression of TGFβ3 gene was detected using immunofluorescent analysis. After AAV-TGFβ3 virus particle with infectious activity was packaged, TGFβ3 expression in NP cells was detected by immunoblotting, and its biological effect on proteoglycan synthesis was detected by antonopulos method and compared with that of AV-TGFβ, in the earlier and later dedifferentiated NP cells.Results For the earlier dedifferentiated NP cells, AAV-TGFβ slowly and stably enhanced proteoglycan synthesis, but AV-TGFβ, rapidly and transiently enhanced its synthesis. For the later dedifferentiated NP cells, AAV-TGFβ3 stably enhanced proteoglycan synthesis, but AV-TGFβ, inhibited its synthesis.Conclusion AAV expression system can mediate TGFβ3 gene to be expressed stably, and AAV-TGFβ3 can enhance proteoglycan synthesis of the earlier and later dedifferentiated NP cells.     

CONSTRUCTING AAV-TGFβ1 AND COMPARISING ITS BIOLOGICAL EFFECTS ON PROTEOGLYCAN SYNTHESIS OF NUCLEUS PULPOUS CELLS WITH AV-TGFβ1

Objective To construct adeno-associated virus express system for TGFβ1 （AAV-TGFβ1） and compare its biological effects on proteoglycan synthesis of the rabbit lumbar disc nucleus pulpous （NP） cells with adenovirus （Ad） express system for TGFβ1 （AV-TGFβ1）. Methods TGFβ1 gene was obtained by polymerase chain reactions （PCR）. The upstream of TGFβ1 contained restriction enzyme site of EcoR Ⅰ, and the restriction enzyme site of Sal Ⅰ was at the downstream of TGFβ1. Using the multiple cloning sites （MCS） in plasmid AAV and the corresponding contained restriction enzyme site in PCR product of TGFβ1, TGFβ1 gene was subcloned into AAV. The recombinant plasmid AAV-TGFβ1 was detected by restriction enzyme digestion and DNA sequencing. Then, AAV-TGFβ1 virus was packaged and TGFβ1 expression mediated by AAV was detected by immunofluence analysis in H293 cells. AAV transfection rate to NP cells was evaluated with AAV-PEGF. After NP cells were respectively transfected by AAV-TGFβ1 virus and AV-TGFβ1 virus, proteoglycan synthesis was detected and compared by using Antonopulos methods. Results DNA sequencing revealed that the PCR-amplified TGFβ1 gene was consistent with NCBI Gene Bank. The recombinant plasmid was proved to be constructed successfully by restriction enzyme digestion. AAV could be transfected into NP cells and mediate an efficient expression of TGFβ1 protein. AV-TGFβ1 virus could quickly enhance the proteoglycan synthesis of the NP cells, but its biological effect was transient. AAV-TGFβ1 virus could enhance stably proteoglycan synthesis. Conclusion AAV-TGFβ1 virus was successful constructed and enhanced stably proteoglycan synthesis of NP cells.     

Fasudil hydrochloride hydrate, a Rho-kinase inhibitor, ameliorates hepatic fibrosis in rats with type 2 diabetes

Background Hyperglycemia may accelerate liver fibrosis.Currently,there is no effective treatment for liver fibrosis induced by type 2 diabetes.The study aim was to investigate whether RhoA/Rho kinase （ROCK） pathway is involved in liver fibrosis in the rats with type 2 diabetes and define the protective effects of fasudil on livers.Methods A rat model of type 2 diabetes was established by high fat diet combined with streptozotocin （30 mg/kg,intraperitoneal injection）.Animals were randomly assigned to 3 groups：control rats,untreated diabetic rats that received vehicle and fasudil-treated diabetic rats that received ROCK inhibitor fasudil hydrochloride hydrate （10 mg/kg per day,intraperitoneal injection,for 14 weeks）.The morphological features of liver were observed by HE staining.Accumulation of collagen in livers was determined by Masson staining and the measurement of hydroxyproline.The mRNA expression of transforming growth factor-β1 （TGFβ1）,connective tissue growth factor （CTGF）,type-Ⅰ,and type-Ⅲ procollagen was assessed with real-time polymerase chain reaction.The phosphorylation of myosin phosphatase target subunit-1 （MYPT1）and the protein levels of TGFβ1 and α-smooth muscle actin （α-SMA） were evaluated by Western blotting.Results Compared with control rats,untreated diabetic rats showed higher values of collagen and hydroxyproline in livers （P ＜0.01）,the phosphorylation of MYPT1 and the protein levels of TGFβ1 and α-SMA were increased （P ＜0.01）,and the mRNA expression of TGFβ1,CTGF,type-Ⅰ,and type-Ⅲ procollagen was upregulated （P ＜0.01）; compared with untreated diabetic rats,treatment with fasudil signifcantly reduced values of collagen and hydroxyproline （P ＜0.01）,and decreased the phosphorylation of MYPT1 and the levels of TGFβ1 and α-SMA （P ＜0.01）,concomitant with the downregulation of TGFβ1/CTGF,type-Ⅰ,and type-Ⅲ procollagen mRNA expression （P ＜0.01）.Conclusions Fasudil ameliorates liver fibrosis in rats with type 2 diabetes at least partly by inhibiting TGFβ1/CTGF pathway and α-SMA expression.Inhibition of RhoA/ROCK may be a novel therapeutic target for liver fibrosis in diabetic non-alcoholic steatohepatitis.     

Expression of USP15, TβR- Ⅰ and Smad7 in Psoriasis

Summary： The deubiquitinating enzyme ubiquitin specific peptidase 15 （USP15） is regarded as a regulator of TGFβ signaling pathway. This process depends on Smad7, the inhibitory factor of the TGFβ signal, and type Ⅰ TGFβ receptor （TβR- Ⅰ ）, one of the receptors of TGFβ. The expression level of USP 15 seems to play vital roles in the pathogenesis of many neoplasms, but so far there has been no report about USP15 in psoriasis. In this study, immunohistochemical staining of USP15, TβR- Ⅰ and Smad7 was performed in 30 paraffin-embedded psoriasis specimens and 10 normal specimens to investigate the expression of USP15, TβR- Ⅰ and Smad7 in psoriasis and to explore the relevance among them. And USP 15 small interfering RNA （USP 15 siRNA） was used to transfect Hacat cells to detect the mRNA expression of TβR- Ⅰ and Smad7. Of 30 cases of psoriasis in active stage, 28, 24 and 26 cases were positive for USP15, TβR- Ⅰ and Smad7 staining, respectively. The positive rates of USP15 and Smad7 were significantly higher in psoriasis specimens than in normal skin specimens （44.1%±26.0% vs. 6.1%±6.6%, 47.2%±27.1% vs. 6.6%±7.1%）, and positive rate of TβR- I （20.3%±22.2%） in psoriasis was lower than that in normal skin specimens （46.7%±18.2%）. There was a significant positive correlation between USP15 and Smad7 expression, and significant negative correlations between USP15 and TβR- Ⅰ expression, and between TβR- Ⅰ and Smad7 expression in psoriasis. After transfection of USP15 siRNA in Hacat ceils, the expression ofTβR- Ⅰ mRNA was up-regulated and that of Smad7 was down-regulated. It is concluded that USP15 may play a role in the pathogenesis of psoriasis through regulating the TβR- Ⅰ/Smad7 pathway and there may be other cell signaling pathways interacting with USP 15 to take part in the development of psoriasis.     

Modulation of transforming growth factor β to platelet-derived growth factor receptor-α of human osteoblasts

Objective To investigate the mechanism and the significance of TGFβ in modulating the expression of Platelet-Derived Growth Factor Receptor-α (PDGFR-α) in human osteoblasts. Methods The osteoblasts were isolated from human fetal calvaria. The percentage of cell increase (PCI) in every 4 hours was calculated to demonstrate the proliferation of osteoblasts affected by PDGF-AA and TGFβ. The osteoblasts were cultured with TGFβ for 24 hours and with PDGF-AA for another 24 hours, and the cells proliferation was shown by PCI too. The osteoblasts were cultured with TGFβ for 24 h, and the PDGFR-α of the cells were measured by immunofluorescent analysis.Results PCI was increased by 48.2% and 22.4% after PDGF-AA and TGFβ were added into the medium for 24 hours respectively (P<0.05), and PCI decreased after the removal of the two cytokines. Preincubated with TGFβ for 24 hours and then stimulated with PDGF-AA, PCI grew slowly. TGFβ downregulated the expression of the PDGFR-α.Conclusion TGFβ can downregulate the mitogenesis of PDGF-AA by lowering the number of PDG     

Construction of Antisense Transforming Growth Factorβ_1 Gene and Its Effect on the Proliferation by Expression in Osteosarcoma Cells

Summary:To construct the antisense transforming growth factorβ1(TGFβ1)gene and investigatethe effect of TGFβ1 autocrine loop blockage on the proliferation of osteosarcoma cells.TGFβ1 cDNAwas cloned by RT-PCR from human osteosarcoma cells(MG-63)and inserted into pcDNA_3 to con-struct an antisense expression vector,which was dubbed pcDNA_3-TGFβ1(-).MTT was used to de-tect the proliferation of osteosarcoma cells transfected by antisense TGFβ1 gene.Our results showedthat the proliferation of the transfected osteosarcoma cells was suppressed markedly.It is concludedthat TGFβ1 autocrine loop blockage in osteosarcoma cells could inhibit cell proliferation,which mightbe helpful for gene therapy of osteosarcoma.     

Cloning and expression of rat transforming growth factor β1 cDNA in osteoblasts

Summary Rat transforming growth factor β1 (rTGFβ1) cDNA from rat lymphocytes was cloned by RT-PCR and inserted into pcDNA3 to construct an eukaryotic expression vector, which was named pcDNA3-TGFβ1. The cloned gene was confirmed to code rat TGFβ1 by restriction enzyme analysis. pcDNA3-TGFβ1 plasmid was transfected into rat osteoblasts by using liposome-mediated gene transfer technique and the expression of TGFβ1 was detected by using immunohistochemical staining assay. It was found that the rat TGFβ1 expression product was obviously detectable in the transfected osteoblasts in 48 h. High expression of TGFβ1 was obtained in the rat osteoblasts in which the constructed TGFβ1 expression vector was transfected.     

人转化生长因子-β1基因克隆、测序及真核表达载体的构建

目的：克隆人转化生长因子-β1（TGF-β1）基因编码区cDNA序列，构建并鉴定TGF-β1真核表达载体。方法：设计含有EcoRI和Xhol Ⅰ酶切位点的TGF-β1 cDNA引物，利用逆转录聚合酶链反应（RT—PCR）法，以人白细胞mRNA为模版，扩增TGF-β1基因，纯化PCR产物，TA克隆，双酶切与pcDNA3质粒表达载体连接，转化感受态大肠杆菌JM109，酶切鉴定阳性董组子，并进行序列测定。结果：琼脂糖凝胶电泳显示，用双酶切后形成分子量1．2kb的条带，符合物理图谱，表明表达载体构建成功，序列测定结果与预测结果完全一致。结论：成功克隆了TGF-β1基因，并成功地构建了真核表达载体pcDNA3-TGF-β1.     

四环素基因表达调控系统调控β-半乳糖苷酶基因在肝癌细胞中的表达

目的：构建调控β-半乳糖苷酶（β-gal）基因表达的四环素基因表达调控载体,验证其在肝癌细胞内调控β-半乳糖苷酶基因的表达,为进一步利用该调控系统调控治疗基因治疗肝癌奠定实验基础。方法：根据2个四环素调控子结合位点（TetO2）基因与pcDNA3.1载体的基因核苷酸序列,设计引物,以pcDNA3.1载体为模板进行PCR。将具有串联2个四环素调控子结合位点（TetO2）基因的PCR产物连接入pcDNA3.1载体CMV启动子下游,构建成pcDNA3.1-TetO2载体,应用ABI 3130 测序仪利用pcDNA3.1-TetO2载体对TetO2 PCR产物进行测序分析。再将β-gal克隆入pcDNA3.1-TetO2载体,构建成受四环素调控表达的β-半乳糖苷酶基因的表达载体pcDNA3.1-TetO2-β-gal。利用脂质体将携带四环素调控子基因（TR）的pcDNA6/TR载体转染到肝癌细胞HepG2中,利用杀稻瘟菌素进行细胞转染的稳定筛选,采用逆转录聚合酶链反应(RT-PCR)法检测TR基因在HepG2细胞内的表达。将pcDNA3.1-TetO2-β-gal载体转染到稳定表达pcDNA6/TR的HepG2细胞中,转染3～4 d后,给予强力霉素（4 mg•L^-1）,利用β半乳糖苷酶原位染色试剂盒染色,检测β-半乳糖苷酶基因的表达。结果：构建的pcDNA3.1-TetO2载体测序结果表明,串联2个四环素调控子结合位点（TetO2）基因片段插入到pcDNA3.1载体CMV启动子基因下游。pcDNA3.1-TetO2-β-gal载体酶切鉴定结果表明,β-gal成功地克隆入pcDNA3.1-TetO2载体。RT-PCR结果显示,TR基因在pcDNA6/TR转染的经杀稻瘟菌素筛选的HepG2细胞内得到稳定表达。给予强力霉素后,β-半乳糖苷酶基因在稳定转染TR 基因的HepG2 细胞 内得以表达;而未给予强力霉素,β-半乳糖苷酶基因在稳定转染TR 基因的HepG2 细胞内表达受到抑制。结论：成功地构建了调控β-半乳糖苷酶基因表达的四环素基因表达调控载体,利用该载体成功地调控了β-半乳糖苷酶基因在HepG2细胞内的表达。     

转染TGF-β1基因的树突状细胞对重症肌无力大鼠T细胞IFN-γ和NO分泌的调节

目的：探讨TGF—β1基因转染的树突状细胞（TGF—β1-DC）对实验性自身免疫性重症肌无力（EAMG）大鼠T细胞IFN-γ和NO分泌的调节作用．方法：近交系、8～10wk龄、雌性Lewis大鼠25只,随机分为5组：正常组、EAMG组、DC对照组、TGF—β1-DC治疗组、生理盐水治疗对照组．除正常组外,其余各组均采用丁氏双鳍电鳐的电器官乙酰胆碱受体蛋白二次免疫的方法复制EAMG大鼠模型．初次免疫后第5日分别皮下注射2×10^6的DC,TGF—β1-DC及等体积的生理盐水,EAMG组不接受任何治疗．初次免疫后7wk,分离脾脏T细胞体外培养48h后分别应用ELISA和化学方法检测T细胞IFN-γ和NO的分泌水平．结果：正常大鼠T细胞体外培养48h后,其上清液中IFN-γ的含量很少,而EAMG组大鼠T细胞培养上清液中IFN-γ的含量显著增加（P〈0．01）．TGF—β1-DC治疗组、DC对照组、生理盐水对照组IFN-γ的含量与EAMG组比较均无统计学差异;正常大鼠T细胞体外培养的上清液中NO的含量很少,EAMG组大鼠T细胞培养上清液中NO的含量明显增加（P〈0．01）．TGF—β1-DC治疗组NO的含量较EAMG组明显增加（P〈0．05）,DC对照组、生理盐水对照组与EAMG组比较无统计学差异．结论：调节EAMG大鼠体内IFN-γ和NO的分泌可能是TGF—β1-DC的治疗机制之一．     

TGF—β1原核表达载体的构建

目的：克隆人TGF—β1基因,为TGF—β1的研究提供平台。方法：应用RT—PCR技术扩增人TGF—β1基因序列,将TGF-β1基因插入载体PET-28a,构建pET28a—TGF—β1重组质粒。结果：经限制性内切酶鉴定及DNA序列测定,重组质粒PET-28a—TGF—β1序列及阅读框架正确。结论：获得了TGF—β1编码序列和表达载体,能满足进一步实验的需要。     

Study of Rat Osteoblasts Transfected by Transforming Growth Factor β1 Gene

Summary: In order to investigate the effect of TGFβ1 gene transfer on the biological characteristics,the effects of gene transfer and supernatant of transfected osteoblasts on the proliferation and ALP activity of osteoblasts were detected by 3H-TdR and MTT. Our results showed that TGFβ1 gene transfer had no effect on the biological characteristics and the activated supernatant of transfected os-teoblasts stimulated proliferation and inhibited ALP activity of osteoblasts. TGFβ1 gene transfer could promote the expression of TGFβ1 and the biological characteristics of transfected osteoblasts were sta-ble, which might be helpful for gene therapy of bone defects in vivo.     

转化生长因子β_1在cos一7细胞中的短暂表达

本文将人转化生长因子β１（ｈＴＣＦβ１）全长ｃＤＮＡ克隆至真核表达载体ｐＭＡＭｎｅｏ的ＮｈｅⅠ位点，利用ＤＥＡＥ一Ｄｅｘｔｒａｎ法将ｈＴＧＦβ１载体导入ｃｏｓ一７细胞中。实验结果表明：所构建的表达载体在ｃｏｓ一７细胞内有转录水平的表达，这为我们进一步研究ｈＴＧＦβ１在其它细胞内的表达与调控之间的关系奠定了基础。     

重组肝细胞生长因子质粒的构建及其在成骨细胞中的表达

目的 构建人肝细胞生长因子(hHGF)真核表达质粒,探讨重组质粒对体外培养胎兔成骨细胞增殖分化的影响,为转基因治疗骨科疾病提供实验基础.方法 RT-PCR扩增人肝脏中hHGF全长cDNA片段,克隆入pcDNA3.1( )真核表达载体中,用脂质体法将pcDNA3.1( )-hHGF质粒转染成骨细胞,通过G418筛选获得阳性克隆,用免疫荧光染色检测hHGF基因在成骨细胞内的表达;MTT法和FCM检测pcDNA3.1( )-hHGF转染后对细胞增殖和细胞周期的影响;采用RT-PCR和ELISA方法检测hHGF在成骨细胞中的表达.NPP法检测碱性磷酸酶合成情况.结果 成功构建hHGF真核表达质粒,免疫组化和RT-PCR检测显示转染成骨细胞后细胞内hHGF mRNA呈现高水平表达;MTT法和FCM检测显示重组质粒转染后能促进成骨细胞的增殖,S期细胞比例增多;ELISA法检测到hHGF在细胞中有分泌性表达.转染重组质粒的成骨细胞合成碱性磷酸酶能力显著提高.结论 成骨细胞经基因转染后可以表达hHGF,外源性hHGF基因能够刺激成骨细胞增殖、分化及成骨活性.     

pcDNA3.1(+)-CYP2J3真核表达载体的构建及在大鼠心肌细胞的表达

目的克隆大鼠CYP2J3基因,与pcDNA3.1(+)真核表达质粒载体连接,转染大鼠心肌细胞检测其表达。方法提取大鼠肝脏组织总RNA,采用逆转录聚合酶链式反应(RT-PCR)和重叠延伸聚合酶链式反应(OE-PCR)的方法扩增大鼠CYP2J3基因,与双酶切的pcDNA3.1(+)连接,构建pcDNA3.1(+)-CYP2J3真核表达载体。转染大鼠心肌细胞,用RT-PCR的方法鉴定其在大鼠心肌细胞的表达。结果得到CYP2J3基因全长序列和真核表达载体pcDNA3.1(+)-CYP2J3。RT-PCR结果显示,转染pcDNA3.1(+)-CYP2J3后的大鼠心肌细胞CYP2J3基因有稳定表达。结论克隆大鼠CYP2J3基因、pcDNA3.1(+)-CYP2J3真核表达载体构建及在大鼠心肌细胞的表达均获成功,为进一步研究CYP2J3基因在细胞中的功能奠定了基础。