肝素对大鼠Thy-1肾炎u-PA/PAI-1表达的影响

目的：研究尿激酶型纤溶酶原激活物／Ⅰ型纤溶酶原激活物抑制因子（u-PA/PAI-1)在大鼠Thy-1肾炎病变进展过程中的变化，以及肝素对其表达的影响。方法：以抗Thy-1单抗成功制备大鼠Thy-1肾炎模型，并用肝素对其进行治疗，分别于1、3、7、14、21、28d处死动物并分别取其肾皮质。应用RT－PCR及Western blot方法检测肾皮质u-PA/PAI-1 mRNA及蛋白表达的变化，以观察肝素对其表达的影响。结果：RT－PCR法显示肾炎模型组（G组）于3－28d的肾皮质u-PA mRNA和3－21d的肾皮质PAI－1 mRNA的表达均高于对照组（P＜0.05或P＜0.01)；肝素治疗组（H组）仅21d时肾皮质u-PA mRNA的表达高于G组（P＜0.05)，而PAI-1 mRNA的表达于3－28d时均低于G组（P＜0.05)。Western blot结果显示3－28d时，G组u-PA和PAI－1蛋白表达量高于对照组（P＜0.05或P＜0.01)，这与RT－PCR检测结果相似；H组肾皮质u-PA蛋白表达量与G组相比差异无显著性，而3－21d时PAI－1蛋白表达量均低于G组（P＜0.05或P＜0.01)。结论：大鼠Thy-1肾炎肾皮质u-PA与PAI－1的表达均随肾小球病变的进展而增强，肝素治疗可能通过干扰或抑制u-PA和PAI－1的表达而发挥其治疗作用。     

PAI-1基因4G/5G多态性与特发性肺纤维化的相关性研究

目的探讨纤溶酶原激活剂抑制物-1（plasminogen activator inhibitor-1,PAI-1）基因启动子区4G/5G多态性与特发性肺纤维化（IPF）的相关性。方法应用聚合酶链反应-限制性片段长度多态性（PCR-RFLP）分析,检测42例IPF患者和164例正常对照组人群PAI-1基因4G/5G多态性。结果PAI-1基因4G/4G、4G/5G、5G/5G基因型频率分布,IPF组分别为31.0%、50.0%、19.0%,对照组分别为17.1%、54.9%、28.0%;4G和5G等位基因频率,IPF组分别为0.560和0.440,对照组分别为0.445和0.555;4G/4G基因型频率IPF组显著高于对照组（P〈0.05）。与4G/5G和5G/5G基因型比较,携带4G/4G型个体发生IPF的风险增加2.18倍,95%CI：1.02～4.68（P〈0.05）。结论PAI-1基因4G/5G多态性与IPF的发病相关,纯合子4G/4G基因型可能是IPF发病的重要危险因素之一。     

体外培养的血管内皮细胞低氧低糖损伤后tPA、PAI-1表达变化

目的：观察体外培养的血管内皮细胞低氧低糖损伤后组织型纤溶酶原激活剂(tPA)、Ⅰ型纤溶酶原激活物抑制因子(PAI-1)表达变化，探讨脑缺血后纤溶系统的变化及机制。材料和方法：制备体外内皮细胞低氧低糖损伤模型，利用HE染色、免疫细胞化学染色观察tPA、PAI-1表达变化。结果：低氧低糖损伤后，tPA、PAI-1表达均明显增强。结论：成功制备体外内皮细胞低氧低糖损伤模型。内皮细胞低氧低糖损伤可以诱导tPA、PAI-1表达增多，进一步说明脑缺血损伤后tPA、PAI-1表达增加并参与损伤过程。     

尼古丁对血管内皮细胞释放t-PA及PAI-1的影响

目的: 研究尼古丁对人脐静脉内皮细胞(HUVECs)释放组织型纤溶酶原激活物(t-PA)和纤溶酶原激活物抑制物-1(PAI-1)的影响。方法: HUVECs培养后接种于24孔培养板中,随机分为对照组及实验组,分别进行以下实验。(1)以0.1、1、10、100 μmol/L 尼古丁孵育HUVECs,12 h后收集各组上清液;(2)以100 μmol/L尼古丁与HUVECs孵育0、4、6、8、12 及24 h,收集各组上清液。采用ELISA法测定各组t-PA和PAI-1的浓度。结果: HUVECs与不同浓度尼古丁孵育12 h后,100 μmol/L尼古丁组PAI-1蛋白较对照组明显增加(P<0.01);0.1、1及10 μmol/L尼古丁组PAI-1蛋白与对照组比较,均无显著差异(均P>0.05);各浓度组t-PA蛋白与对照组比较,均无显著差异(均P>0.05)。HUVECs 与100 μmol/L的尼古丁分别孵育4 、6 、8 、12 及24 h,各组PAI-1蛋白均较对照组明显升高(P<0.05),且其升高呈时间依赖性;各组t-PA与对照组比较,均无显著差异(均P>0.05)。结论: 尼古丁可抑制HUVECs的纤溶活性,对内皮细胞具有损伤作用。     

大鼠局灶性脑缺血再灌注病灶及周围区PAI-1表达

目的:探讨大鼠局灶性脑缺血再灌注后病灶及周围区Ⅰ型纤溶酶原激活物抑制剂(PAI-1)的表达与脑微血管结构改变的关系。方法:采用光镜、电镜、免疫组织化学、Westernblot等技术,观察大鼠局灶性脑缺血再灌注不同时期病灶及周围区脑微血管结构改变及PAI-1表达。结果:大鼠局灶性脑缺血再灌注6h、3d组病灶及周围区脑微血管外间隙水肿及出血,脑微血管基底膜大量破坏,同时再灌注6h、1d组PAI-1表达低于正常对照组,密度值分别为0.16±0.43和0.33±0.61,与对照组(2.19±1.03)差异显著(P＜0.05)。再灌注后期7d组、14d组脑微血管内皮细胞增生,同时PAI-1表达增加,密度值分别为9.48±1.76和8.61±1.35,明显高于对照组(P＜0.01)。结论:大鼠局灶性脑缺血再灌注病灶及周围区脑水肿及出血以6h至3d最严重。PAI-1表达降低可能是导致脑微血管基底膜破坏的原因之一。再灌注后期PAI-1表达增加可能参与脑微血管的再生。     

胃癌中uPA、PAI-1表达及其与血管生成的关系

目的 观察胃癌组织中uPA、PAI-1mRNA及蛋白的表达，并探讨它们与肿瘤分化、血管生成及临床病理因素之间的关系。方法 用原位杂交及免疫组化S-P法检测110例胃癌组织中uPA、PAI-1的表达，根据CD34阳性的血管内皮细胞计数肿瘤组织微血管密度（MVD）。结果 （1）胃癌组织中uPA mRNA和蛋白、PAI-1 mRNA和蛋白阳性表达定位于胞质；uPA的表达随分化程度的降低有逐渐升高的趋势，PAI-1的表达随分化程度的降低有逐渐降低的趋势。（2）110例uPA mRNA及蛋白表达阳性组MVD值显著高于阴性组，差异均具有显著性（P值均＜0．05）。（3）uPA mRNA及蛋白的表达与临床分期呈正相关（P＜0．05），PAI-1的表达与临床分期和淋巴结转移无相关性。（4）uPA mRNA／蛋白与PAI-1 mRNA／蛋白的表达无相关性。结论uPA与促进胃癌的血管生成密切相关，阻断uPA的分泌和作用途径有望对胃癌浸润转移起抑制作用；胃癌组织中PAI-1可能担当重要的调节剂或者是肿瘤细胞防止自身降解的保护剂而不是这个系统的单纯抑制剂。     

中药海乐得对部分肾切除大鼠残余肾脏表达PAI-1、TGFβ mRNA的影响

目的：观察中药制剂海乐得对５／６肾切除（５／６ＮＸ）大鼠残余肾组织表达纤溶酶原激活物抑制物－１（Ｐｌａｓｍｉｎｏｇｅｎａｃｔｉｖａｔｏｒｉｎｈｉｂｉｔｏｒ－ｌ,ＰＡＩ－ｌ）、转化生长因子β（ｔｒａｎｓｆｏｒｍｉｎｇｇｒｏｗｔｈｆａｃｔｏｒ－β,ＴＧＦβ）的影响。方法：海乐得治疗５／６肾切除大鼠６周后处死,检测尿蛋白排泄和血生化变化,制作残肾组织病理和冰冻切片,提取残余肾脏组织ＲＮＡ,分别采用组织原位杂交及Ｎｏｒｔｈｅｒｎ印记杂交方法观察ＰＡＩ－ｌ、ＴＧＦβ的基因表达。结果：中药治疗组残肾组织中ＰＡＩ－ｌ和ＴＧＦβｍＲＮＡ表达、尿蛋白排泄、血清尿素氮和肌酐均明显低于未治疗组,肾脏病理损害以及脂代谢紊乱亦有明显改善。结论：海乐得通过ＰＡＩ－ｌ和ＴＧＦβ途径,能明显改善慢性肾功能衰竭大鼠的肾功能和病理损伤。     

人参皂苷Rb1对白消安诱导人脐静脉内皮细胞表达PAI-1、TF和TGF-β1的影响

目的：探讨人参皂苷Rb1对人脐静脉内皮细胞（HUVECs）的保护作用机制。方法：体外培养HU—VECs，分别用白消安（BU）和人参皂苷Rb1干预，以RT—PCR、实时荧光定量PCR以及ELISA方法检测其PAI-1、TF和TGF—β1 mRNA和蛋白的表达。结果：60mg／LBU使HUVECs PAI-1、TF和TGF—β1蛋白水平明显增高及mRNA表达显著增强，80mg／L人参皂苷Rb1则可明显抑制BU对HUVECs的这种作用。结论：BU可能通过激活TGF—β1信号转导途径而上调PAI-1及TF的表达，增强HUVECs促凝活性；人参皂苷Rb1则可能通过抑制这一途径降低PAI-1及TF表达，保护HUVECs，纠正其高凝、低纤溶活性的异常状态。     

STAT1反义寡核苷酸雾化吸入对肺纤维化大鼠肺组织STAT1、ICAM-1及PDGF-A表达的影响

目的:观察信号转导子与转录活化子1(STAT1)反义寡核苷酸(ASON)雾化吸入对博莱霉素(BLM)致肺纤维化大鼠肺组织STAT1、细胞粘附分子-1(ICAM-1)和血小板衍生生长因子(PDGF)表达的影响.方法:取Wistar大鼠45只,随机分成生理盐水(NS)组、BLM组和ASON组,NS组气管内灌注NS,BLM组和ASON组气管内灌注BLM,随后NS组和BLM组雾化吸入NS,ASON组雾化吸入STAT1 ASON,隔天雾化一次,共4次,分别于雾化后第7天、第14天、第28天处死大鼠各5只,右肺行支气管肺泡灌洗(BAL)进行细胞分类、计数;左肺免疫组化法测定肺组织中STAT1、ICAM-1和PDGF-A蛋白的表达.结果:①与BLM组比较,ASON组各时间点肺泡炎和肺纤维化程度明显减轻(P＜0.05).②与NS组比较,BLM组、ASON组肺组织STAT1、ICAM-1 和PDGF-A表达水平均显著升高(P＜0.01).BLM组第7天STATl、ICAM-1 、PDGF-A在肺组织中表达水平显著升高,随后下降,第28天时仍高于NS组(P＜0.05).与BLM组比较,ASON组各时间点STAT1、ICAM-1 和PDGF-A表达水平降低(P＜0.05).结论:STAT1 ASON雾化吸入能减轻BLM致肺纤维化大鼠肺泡炎和肺纤维化,其机制可能与STAT1被抑制后,炎症细胞在肺部浸润减轻,致炎因子和致纤维化因子分泌减少有关.     

同型半胱氨酸对血管内皮细胞PAI-1活性及其mRNA水平的影响

探讨血浆同型半胱氨酸（Hcy）致血管病变的机制。培养人脐静脉内皮细胞株，用发色底物法测定细胞上清的纤溶酶原激活物抑制物－1（PAI－1）活性，细胞原位杂交及辉度扫描检测PAI－1 mRNA水平。结果表明H 驻作用血管内皮细胞后，PAI－1活性随Hcy浓度增加和Hcy作用时间延长而呈递增趋势，PAI－1 mRNA灰度面积积分值随Hyc浓度的增加而增加。提示Hcy抑制内皮细胞纤溶能力是Hcy致血栓形成和血管病变的一个机制。     

Smad与肺纤维化

转化生长因子β(TGF-β) 是与肺纤维化关系较为密切的细胞因子。Smad蛋白为TGF-β受体后下游的主要信号转导因子,其中Smad3是纤维化疾病的重要介导者,Smad7是TGF-β信号转导途径的主要抑制性蛋白,它们的异常表达可影响TGF-β活性,进而改变纤维化进程。调控Smad3,Smad7的表达可能为治疗纤维化疾病提供一种新手段。     

Expression of TGF-beta1, TbetaRII and Smad4 in colorectal carcinoma

BACKGROUND: Many colorectal carcinomas are resistant to the growth inhibitory response of transforming growth factor-beta (TGF-beta) due to alterations of components along the TGF-beta signaling pathway. The aim of this study was to examine the expression of TGF-beta1, TbetaRII and Smad4 in human colorectal carcinoma and their relationships with cancer growth. METHODS: Immunohistochemistry and in situ hybridization were performed in 38 cases of colorectal carcinoma. RESULTS: Intense signal for TGF-beta1 protein and TGF-beta1 mRNA were found in 71.1% (27/38) and 77.8% (21/27) of colorectal carcinoma, respectively. Intensive TbetaRII mRNA were detected only in 40% (11/27) cancer tissues (p<0.05). 65.8% (25/38) of colorectal carcinoma displayed decreased expression in TbetaRII immunoreactivity staining (p<0.05). Smad4 protein and Smad4 mRNA were reduced in 63.2% (24/38) and 63% (17/27) of tumors, respectively. Smad4 expression was related to tumor differentiation and Duke's stage (p<0.05). Furthermore, TGF-beta1-positive tumors with lymph node metastasis preferentially had significant reduced Smad4 expression (p<0.05). CONCLUSIONS: Down-regulation of TbetaRII as well as the over-expression of TGF-beta1 play a possible role for the escape of colorectal carcinoma from TGF-beta-mediated growth inhibition. Reduced Smad4 is associated with malignancy and progression of colorectal carcinoma.     

Paeonol alleviates CCl4-induced liver fibrosis through suppression of hepatic stellate cells activation via inhibiting the TGF-β/Smad3 signaling

Objective: Paeonol is a natural phenolic component isolated from the root bark of peony with multiple pharmacological activities. We investigated the anti-fibrotic effect and underlying mechanism of paeonol.

Methods: Twenty-four male C57BL/6J mice were divided into 4 groups (n?=?6 in each group), injected with CCl₄ to induce liver fibrosis and administrated with paeonol according to the regimen. The serum activity of ALT and AST, and H&E staining were to assess liver injury. Sirius and Masson staining, and hydroxyproline content were to evaluate the degree of liver fibrosis. TNF-α, IL-6, TGF-β, MDA, GSH-PX, SOD, and CAT were detected to reflect inflammation and oxidative stress. RT-qPCR and Western blot analysis to assess the activation of HSCs and TGF-β/Smad3 signaling.

Results: Paeonol ameliorated liver injury and liver fibrosis, reflected by the decrease of ALT, AST, less lesion in H&E staining, mitigated fibrosis in Sirius and Masson staining, lessened content of hydroxyproline. Paeonol attenuated the level of IL-6 and TNF-α, and elevated the activity of GSH-PX, SOD, and CAT with reducing the level of MDA. The expression of col 1a, α-SMA, vimentin, and desmin were down-regulated and TGF-β/Smad3 signaling pathway was inhibited.

Conclusion: These data demonstrated that paeonol could alleviate CCl₄-induced liver fibrosis through suppression of hepatic stellate cells activation via inhibiting the TGF-β/Smad3 signaling.     

复方红景天防治肝纤维化的实验研究

目的研究复方红景天对四氯化碳诱导的大鼠肝纤维化肝组织TGF-β1基因表达的影响。方法80只SD大鼠随机分组:①空白对照组;②肝纤维化模型组;③复方红景天高剂量组(简称H组);④复方红景天中剂量组(简称M组);⑤复方红景天低剂量组(简称S组)。每组各16只。以CCl4腹腔注射法诱导大鼠肝纤维化,干预组大鼠在造模的同时给予复方红景天灌胃,正常对照组给予橄榄油皮下注射和生理盐水腹腔注射,8周实验结束时处死动物。酶联免疫吸附法检测血清TGF-β1水平,HE染色及免疫荧光观察大鼠肝组织病理学变化和胶原沉积,免疫组化法检测TGF-β1基因表达情况。结果治疗组大鼠肝组织内纤维组织及胶原沉积明显减少。结论复方红景天干预性治疗能够有效地减少大鼠肝组织胶原沉积,使其血清TGF-β1水平下降,并抑制TGF-β1基因表达,干扰TGF-β1介导的肝纤维化信号转导。     

肝纤维化时肝脏OPN和PAI-1的表达变化

目的:研究骨桥蛋白(OPN)及纤溶酶原激活物抑制物(PAI-1)的表达特征及其在肝纤维化时的变化。方法:采用二甲基亚硝胺制作大鼠肝纤维化模型,大鼠肝脏常规HE和天狼猩红染色,采用SABC法做免疫组织化学染色及Western blotting检测OPN和PAI-1蛋白表达,抽提肝组织总RNA,RT-PCR检测OPN mRNA表达。结果:正常大鼠肝组织OPN和PAI-1表达极弱,肝纤维化大鼠肝脏中OPN表达增强,阳性信号散在或弥漫性分布,主要见于小叶内中央静脉周围、纤维间隔内以及周围巨噬细胞胞浆、枯否氏细胞、汇管区的部分肝细胞、肝窦壁内皮细胞。PAI-1在肝纤维化大鼠肝组织汇管区、肝细胞变性坏死处,肝窦周Disse间隙及毗邻以上部位的肝细胞,组织纤维间隔处及其外周细胞亦见阳性染色。Western blotting检测正常大鼠肝脏OPN的蛋白表达极低,肝纤维化组OPN的蛋白表达较正常组显著增强(P0.01)。与正常组比,肝纤维化组PAI-1表达也显著增强。RT-PCR检测结果显示,正常大鼠肝脏OPN mRNA表达极低,肝纤维化大鼠肝脏OPN mRNA的表达明显增强(P0.05)。研究结果证明,肝纤维化时大鼠肝组织OPN及PAI-1的表达水平显著增高。结论:肝纤维化时大鼠肝组织OPN及PAI-1的表达水平显著增高,OPN可能会促进PAI-1的高表达,从而抑制ECM降解、加速肝纤维化进程。     

大黄酸通过抑制miR-21而干预TGF-β1/Smad通路并减轻博莱霉素所致大鼠肺纤维化

目的:观察大黄酸(rhein,RH)对博莱霉素所致肺纤维化大鼠微小RNA-21(miR-21)表达以及转化生长因子β1(TGF-β1)/Smad通路的影响。方法:博莱霉素一次性气管内注射复制大鼠肺纤维化模型,随机分为RH低、中、高剂量组及模型(model)组;正常对照组大鼠气管内注射生理盐水。用药28 d后,HE染色观察各组大鼠肺组织形态学的变化;测定肺系数、肺组织羟脯氨酸含量;real-time PCR检测肺组织中miR-21和TGF-β1/Smad7m RNA表达;Western blot法分析TGF-β1和Smad7蛋白的表达。结果:与model组相比,RH用药组大鼠的肺泡炎及肺纤维化程度有明显降低,肺系数及肺组织羟脯氨酸含量也显著减少,肺组织中miR-21表达下降,TGF-β1的m RNA和蛋白表达水平也明显下降,Smad7的mRNA及蛋白表达水平明显增高(P0.05)。结论:RH抗肺纤维化的作用可能与抑制miR-21的表达,从而干预TGF-β1/Smad信号通路,减少细胞外基质沉积有关。     

Smad2和Smad4在家猫睾丸发育和精子发生中的表达与定位

目的 研究转化生长因子β(TGF-β)超家族的下游信号转导分子Smad2和Smad4蛋白,在不同发育阶段家猫睾丸中的表达和定位,探索Smad2和Smad4蛋白与家猫睾丸发育和精子发生的关系. 方法 应用免疫组织化学技术,研究Smad2和Smad4蛋白在幼年(n=3)、青春期(n=3)和性成熟(n=18)睾丸中的定位,并通过Western blotting技术对免疫组织化学中所用抗体的特异性进行了检测. 结果 免疫组织化学结果显示,Smad2和Smad4蛋白定位于各发育阶段家猫睾丸的生殖细胞、支持细胞和间质细胞的胞质中;Western blotting结果显示,多克隆兔抗Smad2和Smad4抗体与家猫睾丸蛋白提取物中分子量约为58kD、66kD的蛋白条带发生免疫阳性反应. 结论 Smad2和Smad4蛋白在家猫睾丸发育和精子发生的各个阶段均有表达,提示其参与睾丸发育和精子发生的调节.     

TGF-beta1 is increased in a transgenic mouse model of familial Alzheimer's disease and causes neuronal apoptosis

Alzheimer's disease (AD) is a neurodegenerative disorder, due to excess amyloid-beta peptide (Abeta). TGF-beta1 and beta-catenin signaling pathways have been separately implicated in modulating Abeta-neurotoxicity. However, the underlying mechanisms remain unclear. Here, we report that TGF-beta1 and nuclear Smad7 and beta-catenin levels were markedly upregulated in cortical brain regions of the TgCRND8 mice, a mouse model of familial Alzheimer's disease. Coimmunoprecipitation of cortical brain tissue lysates revealed an interaction between Smad7 and beta-catenin. This interaction which was significantly enhanced in the TgCRND8 mice was also associated with an increase in TCF/LEF DNA-shift binding activity. TCF/LEF reporter gene activity was significantly increased in mouse primary cortical neuronal cultures (MCN) from the TgCRND8 mice, compared to controls. Interestingly, exposure of MCN to Abeta(1-42) led to an increase in TGF-beta1 and nuclear levels of both beta-catenin and Smad7. Furthermore, addition of TGF-beta1 to the MCN caused an increase in apoptosis and Smad7 levels. When Smad7 or beta-catenin levels were reduced by siRNA, TGF-beta1-induced apoptosis was suppressed, indicating that both Smad7 and beta-catenin are required for TGF-beta1-induced neurotoxicity. Since Abeta(1-42)-induced TGF-beta1, we suggest that TGF-beta1 may amplify Abeta(1-42)-mediated neurodegeneration in AD via Smad7 and beta-catenin interaction and nuclear localization.     

Significance of pSmad2/3 and Smad4 in hepatitis C virus‐related liver fibrosis and hepatocellular carcinoma

Chronic hepatitis C (CHC) is a major public health problem, especially in Egypt. Risk of hepatocellular carcinoma (HCC) development increases as hepatitis C virus (HCV)‐related liver diseases progress. Smads act as substrates for the transforming growth factor‐beta (TGF‐β) family of receptors. This study aims to assess hepatic expression of pSmad2/3 and Smad4 in CHC with different stages of fibrosis and grades of necro‐inflammation as well as in HCC on top of CHC. This study was done on 33 core liver biopsies from patients with CHC (15 with early fibrosis and 18 with late fibrosis), 15 liver specimens from HCC cases on top of CHC, as well as five normal controls. pSmad2/3 and Smad4 show more immunopositivity, higher percentage of positive hepatocytes and stronger staining intensity in CHC with late fibrosis compared to early fibrosis. pSmad2/3 shows increase of the previous parameters in CHC with high grade activity than those with low activity. Smad4 shows increase of the previous parameters in HCC compared to CHC cases. pSmad2/3 and Smad4 can be used as diagnostic and/or prognostic markers for progression of HCV‐related fibrosis to cirrhosis and further progression to HCC.     

Expression and localization of Smad2 and Smad4 proteins in the porcine ovary

The objective of the present study was to investigate the temporal and spatial expression of Smad2 and Smad4 proteins, the downstream signaling molecules of the transforming growth factor beta (TGF-β) superfamily, in the porcine ovary. Cellular localization of Smad2 and Smad4 proteins was examined using immunohistochemistry. The specificity of the antibodies was examined using Western blot assay. Western blot analyses demonstrated that 52 kDa Smad2 and 60 kDa Smad4 proteins were expressed in the porcine ovary. Immunohistochemistry revealed that Smad2 and Smad4 were widely expressed in the porcine ovary, mainly localized in the oocyte, granulosa and thecal cells at different stages of folliculogenesis. Within the primordial and primary follicles, Smad2 and Smad4 showed strong staining in oocytes and follicular cells. In the antral follicle, strong staining was observed in oocytes, granulosa and theca cells. These findings suggest that Smad2 and Smad4 may be a key regulator of follicular development and growth of oocytes in the porcine ovary.