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1.
Objective To study the effect of retinoid X receptor alpha (RXRα) transfection plus treatment with the RXRα ligand, 9-cis-RA, on the proliferation and phenotype of platelet-derived growth factor (PDGF)-activated hepatic stellate cells (HSCs). Methods PDGF activated rat hepatic stellate cells were transfected with eukaryotic expression vector pcDNA3.1- human RXRα, and confirmed by Western blot. Proliferation of transfected HSC was assayed by bromodeoxyuridine (BrdU) incorporation as well as MTT, and the phenotype (α-smooth muscle actin, desmin) was observed by immunocytochemistry with image analysis. Results Transfection of the RXRα gene and treatment with ligand 9-cis-RA of PDGF-activated HSCs extended the increased expression of RXRα protein for at least 168 hours. Cell proliferation and expressions of alpha-smooth muscle actin (α-SMA) and desmin were blocked, compared with groups of sham-transfected, PDGF-activated, no transfection, no ligand treatment, and irrelevant ligand treated HSCs. Conclusion Transfection with the RXRα gene followed by 9-cis-RA ligand treatment will inhibit the proliferation and reverse the phenotype of activated HSC.  相似文献   

2.
Background Angiotensin Ⅱ (Ang Ⅱ) is a very important vasoactive peptide that acts upon hepatic stellate cells (HSCs), which are major effector cells in hepatic cirrhosis and portal hypertension. The present study was aimed to investigate the effects of Ang Ⅱ and angiotensin Ⅱ type 1 receptor antagonist (AT1RA) on the proliferation, contraction and collagen synthesis in HSCs.
Methods HSC-T6 rat hepatic stellate cell line was studied. The proliferation of the HSC cells was evaluated by MTT colorimetric assay while HSC DNA synthesis was measured by ^3H-thymidine incorporation. The effects of angiotensin Ⅱ and AT1RA on HSCs contraction were studied by analysis of the contraction of the collagen lattice. Cell culture media were analyzed by RT-PCR to detect secretion of collagen Ⅰ (Col Ⅰ), collagen Ⅲ (Col Ⅲ) and transforming growth factor β1 (TGF-β1) by enzyme linked immunosorbent assay. HSC was harvested to measure collagen Ⅰ, collagen Ⅲ and tissue inhibitor of metalloproteinase-1 (TIMP-1) mRNA expression.
Results Ang Ⅱ ((1×10^-10-1×10^-4)mol/L)stimulated DNA synthesis and proliferation in HSCs compared with untreated control cells. AT1RA inhibited angiotensin Ⅱ induced proliferation of HSCs. A linear increase in the contractive area of collagen lattice correlated with the concentration of angiotensin Ⅱ (1×10^-9-1×10^-5 mol/L) and with time over 48 hours. AT1RA blocks angiotensin Ⅱ induced contraction of collagen lattice. Col Ⅰ, Col Ⅲ and TGF-β1 levels of the Ang Ⅱ group were higher than those of control group and this increase was downregulated by AT1RA. The mRNA expressions of Col Ⅰ, Col Ⅲ and TIMP-1 were higher in HSCs from the Ang Ⅱ group than the control group and downregulated by AT1RA.
Conclusions Angiotensin Ⅱ increased DNA synthesis and proliferation of HSCs in a dose-dependent manner, stimulated the contraction of HSCs dose- and time-dependently. Angiotensin also promoted excretion of Col I, Col Ⅲ and TGF-β1 lev  相似文献   

3.
Objective To investigate the cellular immune mechanism of thyroid associated ophthalmopathy (TAO) and provide a basis for treating TAO with cytokine or anti-cytokine agents, we determined whether interferon (IFN)-γ and interleukin (IL)-4, representative cytokines of Th1 and Th2 cells, may have some effect on the development and progression of TAO.Method Retroorbital fibroblasts (RF) proliferation and the synthesis of hyaluronic acid (HA) and type Ⅳ collagen were measured with liquid scintillation and radioimmunoassay. Results IFN-γ stimulated RF proliferation and HA synthesis and had a significant inhibitory effect on type Ⅳ collagen synthesis. IL-4 stimulated proliferation and type Ⅳ collagen synthesis in RF and had inhibitory effect on HA synthesis. When IFN-γ (100U/ml) and IL-4 (1μg/L) were incubated together with RF, they antagonized their respective stimulatory or inhibitory effect on the proliferation and synthesis of HA and type Ⅳ collagen. Thyrotropin (TSH) stimulated RF proliferation and type Ⅳ collagen synthesis in a dose-dependent manner, while only at high dose (100U/L and 200U/L), stimulated RF to synthesize HA. Conclusions IFN-γ, a representative cytokine of Th1 cells, is responsible for the inflammatory process of TAO; whereas IL-4, a representative cytokine of Th2 cells, has some effect on the repair process. IL-4 could antagonize the inflammatory effect of IFN-γ on RF. TSH may have aggravating effect on the pathogenesis of TAO.  相似文献   

4.
Background The function of peroxisome proliferator-activated receptor γ (PPARγ) in hepatic fibrogenesis remains largely unknown. Curcumin is a natural substance extracted form Curcuma Longa Linn and has a variety of pharmacological effects. In this study, the effects of curcumin on the proliferation, activation and apoptosis of rat hepatic stellate cells (HSCs) through PPARγ signaling were investigated. Methods HSCs were isolated from the normal Sprague Dawley rats through in situ peffusion of the liver with Pronase E and density-gradient centrifugation with Nycodenz. Cells were treated with curcumin, troglitazone, salvianolic acid B or GW9662. The effect on HSCs proliferation was determined by MTT colorimetry. Total RNA was extracted by TRizol reagent and gene levels were determined by semi-quantitative RT-PCR. Total cellular and nuclear protein were isolated and separated by 10% sodium dodecy Isulfate polyacrylamide gel electrophoresis. Protein levels were determined by Western blot. Cell apoptosis was detected by Hoechst 33258 staining. PPARγ subcellular distribution was detected by immunofluorescent staining. The activities of MMP-2 and 9 were measured by Gelatin zymograph assay. Results Curcumin suppressed HSCs proliferation in a dose-dependent manner. As HSCs underwent gradual activation with culture prolongation the PPARγ nuclear expression level decreased. Curcumin up-regulated PPARγ expression and significantly inhibited the production of a-SMA and collagen Ⅰ. PPARγ is expressed in the cytoplasm and nucleus and is evenly distributed in HSCs, but accumulated in the nucleus of HSCs and disappeared from cytoplasm after curcumin treatment. Hoechst 33258 staining showed that curcumin induced the apoptosis of culture-activated HSCs and significantly increased pro-apoptotic Bax expression and reduced anti-apoptotic Bcl-2 expression. Cyclin D1 gene, activated NFKB p65 protein and TGFβR-Ⅰ protein expression were down-regulated significantly by curcumin. The activities of MMP-2 and MMP-9 were enhanced significantly by curcumin. Conclusions Curcumin can inhibit the proliferation and activation of HSCs, induce the apoptosis of activated HSCs and enhance the activities of MMP-2 and MMP-9. The effects of curcumin are mediated through activating the PPARγ sianal transduction pathway and associated with PPARγ nuclear translocation/redistribution.  相似文献   

5.
Objective:To investigate the effects and mechanisms of interferon in combination with alltrans retinoic acid (ATRA) on proliferation and differentiation of ATRA-resistent APL cell. Methods :After MR2 cells (ATRA-resistance cell line) were treated with IFN-α, IFN-γ and ATRA alone or IFN-α and IFN-γ in combination with ATRA respectively. The cell proliferation was tested by MTT test and the cell differentiation was tested through light microscope by NBT test and flow cytometry (FCM). The expres sion of promyelocytic leukemia (PML) protein was observed by indirect immune fluorescent method. Results: Both IFN-α and IFN-γ could inhibit the proliferation and induce the differentiation of MR2 cells to some extent. The effects were more obvious after both interferons in combination with ATRA respectively (P〈0.05). Moreover, the maturation of MR2 cells induced by IFN-γ+ATRA group was more higher than that by IFN-α+ATRA group (P〈0. 05). Both interferons could induce the expressions of PML protein. Conclusion:Both interferons can inhibit MR2 cells proliferation, which may be related to the expression of PML protein induced by both interferons. The inducing differentiation effects of IFN-γ+ATRA group on MR2 cells are more powerful than those of IFN-aq-ATRA group, which may be related to the different signal transduction pathway of both interferons.  相似文献   

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8.
Objective: To investigate the effects of baicalin on expression of inducible nitric oxide synthase (iNOS) in fibroblasts and its mechanisms in treating psoriasis. Methods: Fibroblasts cultured in vitro were stimulated with tumor necrosis factor-α(TNF-α), interferon-γ (IFN-γ), interleukin-8 (IL-S) in different groups. iNOS was detected by western blot and immunocytochemistry assay, and in addition, the effects of baicalin on its expression were investigated. Results: Fibroblasts did not express iNOS without cytokine stimulation. When treated for 24 h with 1. 0× 106 U/L TNF-α, 0.2× 106U/L IFN-γ, 0.2× 106 pg/L IL-8 alone or in combinations indicated, fibroblasts produced iNOS when stimulated by TNF-α alone while neither IFN-γ nor IL-8 could induce the production of iNOS. The combination of TNF-α and IL-8 induced a strong expression of iNOS, the combined exposure of three kinds of cytokines showed an even stronger effects. The strongly stained area was in the cytoplasm near the nuclei. Expression of iNOS induced by TNF-α and IL-8 was inhibited by 50 μg/ mi of baicalin. Conclusion: Fibroblasts might express iNOS when stimulated by certain cytokines. Baicalin decreased production of nitric oxide through inhibiting the expression of iNOS, furthermore it reduced inflammation, which might be part of its mechanisms in treating psoriasis.  相似文献   

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10.
Objective To explore the possible mechanism of vitamin E against atherosclerosis through its preventive effect on tumor necrosis factor (TNF) inducing endothelial cell injury.Methods Bovine aortic endothelial cells were incubated in culture media with TNF-alpha (400 U/ml) and vitamin E (12.5 microM, 25.0 microM and 50.0 microM respectively) for 72 h.The morphology, proliferation, apoptosis and adherence of endothelial cells were investigated with phase-contrast microscope, MTT method, flow cytometry analysis and cell count respectively.Results Compared with TNF group, the phenomena of endothelial cell deformity and shedding were slighter, the number of adhered HL60 monocyte cells and G1-phase cells were less, and the inhibitory rate and the apoptotic peaks were significantly lower in vitamin E groups.Conclusion The results suggested that vitamin E has definite protective effects on injury induced by TNF as shown in morphology, proliferation and apoptosis of endothelial cells in vitro.  相似文献   

11.
R68umeObjectifPourdtudierlk/ftdevitamineEsurlaprolofdrationetla8ynthdsedecollagdnedescellulesstellairesdesrats.MdthodesLescellulesstellairesdtaientisoldesaveclamdthodeFriedmanmodofide,Le8cellulesisoldesdtaientcultivdesettraitdesparinterleukiene-2.LeselfetBdevitamineEdtaientdtudidssurlaprolofdrationetlasynthdsedecollagdneavecde8essaisd'incorPorationde3H-thymidineet'H-proline.RJsuItats1.LaprolWrationetlasynthdsedecollagdnedescellulesstellairesdtaientaugmentdessousl'actiondeinterleukine-2.2…  相似文献   

12.
目的:研究维生素E(VitE)对大鼠贮脂细胞增殖及胶原合成的影响。方法:以链酶蛋白酶和胶原酶液原位循环灌注法分离大鼠贮脂细胞,以肿瘤坏死因子-α作为刺激因素,采用3H-胸腺嘧啶核苷(3H-TdR)和3H-脯氨酸(3H-proline)掺入法分别测定VitE对贮脂细胞增殖和胶原合成的影响,并在倒置显微镜下观察贮脂细胞的形态。结果:(1)肿瘤坏死因子-α能明显促进贮脂细胞增殖,并能明显抑制其胶原合成;(2)VitE能显著抑制肿瘤坏死因子-α引起的贮脂细胞增殖,并能增强肿瘤坏死因子-α对贮脂细胞胶原合成的抑制作用。结论:VitE对贮脂细胞增殖及胶原合成具有抑制作用,这可能是VitE抗肝纤维化作用的重要机制之一。  相似文献   

13.
来氟米特对肝星状细胞增殖和胶原合成的影响   总被引:4,自引:0,他引:4  
目的:研究来氟米特活性代谢物A771726对肝星状细胞(HSC)增殖和胶原合成的影响.方法:用链蛋白酶和胶原酶原位肝灌注、Nycodenz密度离心法分离大鼠HSC和Kupffer细胞,制备Kupffer培养上清液(KCCM),并以不同浓度、不同培养时间的CCl4损伤的KCCM作为刺激因素观察了A771726对HSC增殖(3H-TdR掺入法)和胶原合成(3H-Pro掺入法)的影响.ELISA法测定KCCM内TGF-β、TNF-α和IL-1含量.结果:HSC和Kupffer细胞得到较好的分离.CCl4损伤的KCCM显著增加HSC增殖和胶原合成,并且稀释度为1:2的KCCM在培养7 d时,对HSC增殖和胶原合成的刺激作用明显.A771726(0.001~10 μmol/L)对CCl4损伤的KCCM刺激HSC增殖和胶原合成有不同程度的抑制作用,并且A771726(0.001~10 μmol/L)明显抑制CCl4损伤KCCM内升高的TGF-β、TNF-α和IL-1水平.结论:CCl4损伤的KCCM可明显刺激HSC增殖和胶原合成,而A771726对此有明显的抑制作用,并且与其抑制致HSC激活的因子如TGF-β、TNF-α和IL-1分泌有关.  相似文献   

14.
福尔肝6号对肝星状细胞增殖的影响   总被引:8,自引:0,他引:8  
目的:探讨福尔肝6号对肝星状细胞增殖影响的抗肝纤维化作用机理。方法:采用血清药理学实验方法作用于活化的大鼠肝星状细胞(HSC),以^3H-TdR掺入法观察肝星状细胞增殖。结果:福尔肝6号和秋水仙碱药物血清能抑制肝星状细胞增殖,福尔肝6号药物血清组优于秋水仙碱药物血清组。结论:福尔肝6号药物血清能抑制HSC的增殖,从而减少胶原等ECM合成。  相似文献   

15.
目的 观察干扰素α对大鼠纤维化时星状细胞增殖,I,Ⅲ型前胶原mRNA表达和肝脏胶原沉积的影响。方法 以CCl4制造肝纤维化模型,培养肝星状细胞,抽提RNA,用地高辛标记I,Ⅲ型前胶原和胶原酶cDnA探针,Northern杂交分析I,Ⅲ型前胶原和胶原酶mRNA表达,Dotblot测定大鼠肝I,Ⅲ型胶原沉积,分别用^3H-TdR和^3H-脯氨酸掺入观察干扰素α对星状细胞增殖和胶原合成的影响。结果 干扰  相似文献   

16.
目的观察维生素C和E对瘦素诱导肝星状细胞(hepatic stellate cell,HSC)的增殖及组织抑制基质金属蛋白酶-1(tissue inhibitor of matrix metalloproteinase-1,TIMP-1)上调的影响。方法培养人HSC,按照分组加入瘦素和(或)不同浓度的维生素C和E。磺基罗丹明B法检测HSC增殖,活性氧(ROS)检测探针2,7-二氯二氢荧光素二乙酯检测ROS,酶联免疫吸附实验测定TIMP-1的浓度。结果维生素C为100、200、400μmol/L时抑制瘦素诱导的HSC增殖效果和瘦素组比较差异有统计学意义(P<0.05),维生素E为80、160、320μmol/L时与溶媒瘦素组比较差异有统计学意义(P<0.05)。最高浓度联合后,抑制瘦素诱导的HSC增殖效果更明显(P<0.05)。同时上述浓度均能抑制瘦素诱导的ROS产生(P<0.05),抑制瘦素诱导的TIMP-1产生(P<0.05),最高浓度联合组抑制TIMP-1效果较单独用药时明显(P<0.05)。结论抗氧化剂维生素E和C可能通过抑制瘦素诱导的氧化应激,抑制HSC增殖以及TIMP-1的产生。  相似文献   

17.
醛固酮与螺内酯对肝星状细胞增殖及胶原合成的影响   总被引:4,自引:0,他引:4  
Yao JF  Yao XX  Fang HM  Cui DL  Bai WY 《中华医学杂志》2003,83(20):1823-1825
目的 探讨醛固酮 (ALD)、螺内酯对大鼠肝星状细胞 (HSC)增殖、胶原合成的影响。方法 大鼠HSC培养 ,在不同浓度的ALD、螺内酯作用下 ,采用3 H 胸腺嘧啶核苷 (3 H TdR)、3 H 脯氨酸 (3 H Pro)掺入法及流式细胞技术观察ALD、螺内酯对HSC增殖及胶原合成的影响。结果 ALD在 10 -4mol/L高浓度时3 H TdR、3 H Pro掺入量与对照组相比明显增多 (P <0 .0 5 ) ,螺内酯在浓度高于 10 -6mol/L时 ,HSC3 H TdR、3 H Pro掺入量明显减少 ,螺内酯阻止HSC于G1期 ,ALD +螺内酯组与对照组相比差异无显著意义 (P >0 .0 5 )。结论 高浓度ALD可以促使HSC增殖 ,其拮抗剂螺内酯明显抑制HSC的增殖及合成胶原。  相似文献   

18.
目的观察丹参素对PDGF-BB刺激下大鼠肝星状细胞活化增殖,Ⅰ、Ⅲ型胶原合成与分泌,ERK1/2和PI3K通道蛋白表达的影响,探讨丹参素抑制肝纤维化的分子机制。方法用不同浓度丹参素(0.250、0.125、0.062 mmol/L)、ERK通道特异性抑制剂UO126(20 nmol/L)和PI3K通道特异性抑制剂LY294002(20 nmol/L)分别作用于经血小板衍生生长因子PDGF-BB(10 ng/ml)处理的大鼠肝星状细胞(HSC)48 h,CCK8法检测HSC增殖活性,免疫化学染色法测定Ⅰ、Ⅲ型胶原合成,酶联免疫吸附法观察Ⅰ、Ⅲ型胶原分泌,Western blot测定ERK1/2、p-ERK1/2、AKT和p-AKT蛋白表达。结果 PDGF-BB 10 ng/ml处理后,HSC增殖明显增加(0.139±0.009),丹参素能抑制PDGF-BB刺激大鼠HSC增殖的作用,并随丹参素浓度增加(0.062、0.125、0.250 mmol/L)细胞增殖受到的抑制作用越强(0.102±0.008、0.083±0.007、0.066±0.014,P<0.05),Ⅰ、Ⅲ型胶原合成及分泌均显著减少(P<0.05),p-ERK1/2和p-AKT蛋白表达均显著降低(P<0.05)。结论丹参素可通过抑制PDGF-BB诱导的HSC增殖和活化,同时抑制与肝纤维化密切相关的MAPK、PI3K途径中ERK、AKT蛋白的磷酸化,负性调控肝纤维化过程,其机制可能与抑制ERK1/2和PI3K信号转导通路有关。  相似文献   

19.
肝星状细胞激活的分子机制与抗肝纤维化治疗   总被引:1,自引:0,他引:1  
肝星状细胞(HSC)激活是肝纤维化发生的中心环节,其激活过程可分为始动阶段(旁分泌刺激和转录调控因素启动级联瀑布式的细胞反应)和持续阶段(旁分泌或自分泌刺激和细胞外基质重建共同维持HSC活化的表型反应)。肝脏中多种细胞和细胞因子参与调节了HSC的激活过程。活化型HSC的表型变化主要包括细胞增殖、收缩和纤维形成等。抗肝纤维化治疗策略主要包括调控HSC活化增殖或促其凋亡、抑制胶原合成或促其降解、细胞因子治疗和间充质干细胞治疗等。  相似文献   

20.
目的:观察奥曲肽(OCT)对肝星状细胞(HSC)Ⅰ型、Ⅲ型胶原和基质金属蛋白酶2(MMP-2)基因及蛋白表达的影响,阐明其抗肝纤维化的机制。方法:体外培养rHSC-99细胞,以不同浓度OCT作用24 h后,MTT法观察细胞增殖,ELISA法测定上清液中Ⅰ型、Ⅲ型胶原,半定量RT-PCR法检测MMP-2、Ⅰ型及Ⅲ型胶原mRNA表达。结果:与对照组比较,OCT能显著抑制体外培养的rHSC-99增殖(P<0.05),在一定剂量范围(1~8 μg?L-1)内,随着OCT浓度升高,细胞增殖抑制率增加。与对照组比较,OCT各组细胞上清液中Ⅰ型、Ⅲ型胶原浓度明显降低(P<0.05),且Ⅰ型、Ⅲ型胶原mRNA表达水平显著降低(P<0.05)。与对照组比较,OCT组MMP-2 mRNA呈高表达(P<0.05)。结论:OCT能抑制HSC增殖,下调Ⅰ型和Ⅲ型胶原mRNA及其蛋白表达,上调MMP-2 mRNA表达水平,这可能是其抗肝纤维化作用机制之一。  相似文献   

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