阿托伐他汀联合环孢素A对百草枯中毒大鼠肺纤维化的缓解作用

目的探索阿托伐他汀联合环孢素A对百草枯中毒大鼠肺纤维化的疗效。方法 Wistar大鼠50只随机分为5组,每组10只。对照(Control)组给予生理盐水1 mL灌胃,其余4组单次给予单剂量百草枯20 mg/kg灌胃以染毒。然后,模型(PQ)组以生理盐水1 mL灌胃;阿托伐他汀(PQ+STN)组、环孢素A(PQ+CsA)组以及联合用药(PQ+STN+CsA)组分别以阿托伐他汀20 mg/kg、环孢素A 10 mg/kg以及阿托伐他汀20 mg/kg+环孢素A 10 mg/kg灌胃,每天1次,共7 d。HE和Masson.s染色观察肺组织病理学变化;测定肺湿重/干重比、羟脯氨酸含量;酶联免疫吸附实验(ELISA)检测肺组织TNF-a、IL-1 b、IL-6含量;Western blot检测TGF-b、CollagenⅠ、CollagenⅢ、MMP-2、MMP-9、E-cadherin、Vimentin和a-SMA的蛋白表达;试剂盒检测超氧化物歧化酶(SOD)、丙二醛(MDA)、还原型谷胱甘肽(GSH)等指标。结果 HE染色结果显示,与Control组比较,PQ组肺泡壁变厚、免疫细胞聚集、肺泡破裂;Masson.s染色显示肺组织明显纤维化。与PQ组比较,PQ+STN组和PQ+CsA组均一定程度减轻肺损伤和纤维化,PQ+STN+CsA组对肺损伤和纤维化的改善最明显。与Control组比较,PQ组肺湿重/干重比升高(P0.05),肺羟脯氨酸含量增加(P0.01),TNF-α、IL-1β和IL-6升高(P0.01),MDA增加(P0.01),SOD和GSH降低(P0.01),纤维化标志蛋白TGF-β、CollagenⅠ和CollagenⅢ升高(P0.01),MMP-2、MMP-9、Vimentin和α-SMA升高(P0.01),E-cadherin降低(P0.01)。与PQ组比较,PQ+STN组、PQ+CsA组和PQ+STN+CsA组肺湿重/干重比、肺羟脯氨酸含量、TNF-α、IL-1β、IL-6、MDA、TGF-β、CollagenⅠ、CollagenⅢ、MMP-2、MMP-9、Vimentin和α-SMA降低(P0.05),SOD、GSH和E-cadherin升高(P0.05)。结论阿托伐他汀联合环孢素A能更有效减轻百草枯中毒导致的肺纤维化,控制氧化应激和炎症,其机制可能与其对细胞移动能力相关蛋白的调控有关。     

RNA干扰沉默Smad3基因对百草枯致小鼠肺间质纤维化的治疗作用

目的通过RNA干扰技术沉默小鼠肺组织中Smad3基因,观察其对百草枯(PQ)所致肺间质纤维化是否具有保护作用。方法利用小鼠L929成纤维细胞,体外验证抑制Smad3基因表达的有效shRNA,并进一步将其合成进重组腺病毒。实验小鼠分为三组,在小鼠染毒后2h,气管内分别注入PBS、非靶向重组腺病毒和靶向重组腺病毒。不同时间点(0d,7d,28d)对每组6只小鼠进行处理,留取肺组织标本。提取肺组织中总RNA,Real time PCR检测肺组织中Smad3、I型前胶原mRNA表达,Western Blot检测肺组织细胞核中Smad3蛋白表达,羟脯氨酸检测试剂盒分析肺组织中羟脯氨酸的含量以及肺组织HE染色后观察组织病理学变化。结果同PBS组、非靶向重组腺病毒组相比,靶向重组腺病毒有效抑制了肺组织内Smad3 mRNA和蛋白表达。重组腺病毒介导的shRNA转染进一步抑制了肺组织中I型前胶原mRNA表达和羟脯氨酸的产生,减轻了PQ所致的肺间质纤维化的形成。结论Smad3对百草枯引起的肺间质纤维化有重要作用,RNA干扰抑制肺组织Smad3基因表达可能是一种有效的治疗该病的方法。     

硫化氢通过抑制TGF-β1/Smad信号通路抗大鼠肺纤维化

目的观察硫化氢(H2S)对博莱霉素所致大鼠肺纤维化的影响,并探讨其是否通过转化生长因子-β1(TGF-β1)/Smad信号通路发挥作用。方法 SD大鼠50只随机分为正常对照组、假手术组、模型组、硫氢化钠(Na HS)组和地塞米松组,每组10只,假手术组大鼠以生理盐水气管内注入,而后3组大鼠以博莱霉素A5气管内注入制备肺纤维化模型。自第2天起,Na HS组、地塞米松组大鼠分别以Na HS、地塞米松腹腔注射,其余3组腹腔注射等量生理盐水。全部大鼠第28天处死,留取肺组织,行HE和Masson染色,通过试剂盒测定肺组织羟脯氨酸(HYP)含量,采用实时荧光定量PCR和Western blot分别检测肺组织中TGF-β1、Smad2、Smad3、Smad7、α平滑肌肌动蛋白(α-SMA)、Ⅰ型胶原(ColⅠ)、Ⅲ型胶原(ColⅢ)m RNA和蛋白表达。结果与模型组比较,Na HS组和地塞米松组肺泡炎症与肺纤维化程度明显减轻(P0.01)。与正常对照组或假手术组比较,模型组肺组织HYP含量以及TGF-β1、Smad 2、Smad 3、α-SMA、ColⅠ、ColⅢm RNA和蛋白表达水平升高,但Smad 7 m RNA和蛋白表达水平降低,差异均有统计学意义(P0.01)。通过Na HS或地塞米松处理后,肺组织HYP含量以及TGF-β1、Smad 2、Smad 3、α-SMA、ColⅠ、ColⅢm RNA和蛋白表达水平减少,而Smad 7 m RNA和蛋白表达水平增加,与模型组比较,差异均有统计学意义(P0.01)。然而,Na HS组与地塞米松组以及假手术组与正常对照组上述指标相比无显著性差异(P0.05)。结论 H2S可能通过抑制TGF-β1/Smad信号转导通路下调α-SMA表达,从而减少ColⅠ、ColⅢ合成发挥抗大鼠肺纤维化作用。     

博来霉素致大鼠肺纤维化模型肺组织的动态病理变化及其发生机制

目的： 了解博来霉素（BLM）致大鼠肺纤维化模型肺组织的动态病理变化,探讨BLM致肺纤维化的作用机制。方法：60只雄性SD大鼠采用随机数字表法分为正常对照组（N组）和肺纤维化模型组（B3、B7、B14、B28、B56组）,每组10只。除N组外,其余各组采用气管内注入BLM致大鼠肺纤维化模型, 分别于3、7、14、28、56 d处死各组大鼠,右肺行苏木精-依红（HE）、Masson胶原及天狼猩红染色,测定左肺羟脯氨酸（HYP）的含量。 RT-PCR法半定量测定转化生长因子-1（TGF-β1）、基质金属蛋白酶-9（MMP-9）和基质金属蛋白酶组织抑制物-1（TIMP-1）mRNA在肺内的表达。免疫组化法观察TGF-β1、MMP-9及TIMP-1蛋白在大鼠肺组织的表达。结果：(1) 模型组大鼠肺组织HYP含量显著高于N组（P<0.05）,模型组大鼠肺组织肺泡炎症的程度也明显重于N组,B14、B28和B56组大鼠肺纤维化的程度明显重于N组,大鼠在灌注BLM后不同时点其肺组织有着不同的病理变化。 (2) TGF-β1、MMP-9及TIMP-1在正常组大鼠肺脏中即有表达,但表达较弱,灌注BLM后它们的表达均增强,不同时点它们在肺组织内的分布有不同的特点。结论：给予后不同时点大鼠肺组织有着不同的病理变化特点,TGF-β1、MMP-9和TIMP-1在BLM诱导的肺纤维化形成过程中起着重要的调节作用。     

阿托伐他汀对ApoE基因敲除小鼠血管外膜成纤维细胞表型的影响

目的:观察载脂蛋白E基因敲除(ApoE~(-/-))小鼠动脉粥样硬化斑块形成过程中血管外膜α-平滑肌肌动蛋白(α-SMA)和转化生长因子-β1(TGF-β1)的表达变化,同时探讨阿托伐他汀抗动脉粥样硬化的作用机制。方法:选择40只6周龄雄性ApoE~(-/-)小鼠随机分为模型组和阿托伐他汀干预组,给予高脂饲料喂养。阿托伐他汀干预组给予阿托伐他汀(20 mg·kg~(-1)·d~(-1))灌胃,模型组给予等量生理盐水灌胃。20只同龄C57BL/6小鼠给予普通饲料喂养作为正常对照组。各组小鼠喂养至10、15周龄,在各个时点处死动物,取升主动脉制备连续切片,通过Movat染色进行形态学观察,测量并计算血管外膜厚度及斑块相对面积;天狼星红染色检测胶原的表达;免疫组织化学染色检测不同时点血管外膜α-SMA及TGF-β1的表达变化。用实时荧光定量PCR检测胸主动脉外膜中TGF-β1 mRNA的表达水平,通过Western blot法检测主动脉外膜中TGF-β1蛋白的表达。结果:与模型组相比,阿托伐他汀干预组的斑块相对面积明显减小,血管外膜厚度及胶原合成明显下降;免疫组化结果显示15周龄模型组血管外膜α-SMA及TGF-β1的表达高于10周龄模型组;与模型组相比,阿托伐他汀干预组血管外膜α-SMA及TGF-β1的表达明显下降。各时点模型组的TGF-β1 mRNA和蛋白的表达明显高于对照组,给药干预后TGF-β1 mRNA和蛋白的表达明显降低。15周龄模型组血管外膜TGF-β1 mRNA和蛋白的表达高于10周龄模型组。结论:阿托伐他汀可能通过下调TGF-β1的表达调控血管外膜成纤维细胞表型的改变,进而延缓ApoE~(-/-)小鼠动脉粥样硬化的进程。     

丹皮酚通过抑制miR-21表达减轻博莱霉素诱导的大鼠肺纤维化

目的研究丹皮酚(PAE)通过抑制微小RNA-21(miR-21)减轻博莱霉素(BLM)诱导肺纤维化的相关机制。方法将SD大鼠随机分为对照组、BLM组、阳性对照(PC)组、PAE组,比较各组大鼠的肺纤维化相关指标,miR-21、Smad7的mRNA相对表达水平,及Smad7、TGF-β1、COLIA1、α-SMA蛋白水平;将制备好的纤维细胞分为对照组,TGF-β1组,PAE-L组,PAE-M组,PAE-H组,miR-21抑制剂组,检测各组细胞中miR-21、Smad7的mRNA相对表达水平及Smad7、COLIA1、α-SMA蛋白水平,并验证miR-21与Smad7的靶向关系。结果与对照组相比,BLM组大鼠的肺系数、羟脯氨酸、肺纤维化程度,miR-21mRNA表达水平,TGF-β1、COLIA1、α-SMA蛋白表达水平显著升高均显著升高(P0.01),Smad7的mRNA及蛋白表达水平显著降低(P0.01),与BLM组相比,PC组和PAE组大鼠的肺系数、羟脯氨酸、肺纤维化程度均显著降低(P0.01);与BLM组相比,PC组和PAE组大鼠肺组织中miR-21 mRNA水平,TGF-β1、COLIA1、α-SMA蛋白水平显著降低,Smad7的mRNA及蛋白水平显著升高(P0.01);与对照组相比,TGF-β1组成纤维细胞中miR-21的mRNA及COLIA1、α-SMA蛋白水平显著升高(P0.01),Smad7的m RNA及蛋白水平显著降低(P0.01);与TGF-β1组相比,PAE-L组、PAE-M组、PAE-H组、miR-21 inhibitor组成纤维细胞中miR-21的mRNA水平及COLIA1、α-SMA蛋白水平显著降低(P0.01),Smad7的mRNA及蛋白表达水平显著升高(P0.01);靶基因数据库预测及双荧光素酶报告实验表明,miR-21靶向抑制Smad7。结论 PAE可能通过抑制miR-21表达靶向促进Smad7表达,并抑制TGF-β1表达来减轻BLM诱导的肺纤维化。     

紫檀茋减轻百草枯诱导的模型大鼠肺纤维化

目的 探究紫檀茋(Pte)减轻百草枯(PQ)诱导大鼠肺纤维化的作用及机制。方法 将大鼠随机分为对照(control)组,PQ组(1次性灌胃50 mg/kg百草枯),低、中、高剂量Pte干预组(灌胃PQ 30 min后分别灌胃25、50和100 mg/kg Pte。每天1次,共7 d。)。治疗7 d后,用苏木精-伊红(HE)染色评价肺组织形态,用Masson三色染色评价肺纤维化。ELISA检测支气管肺泡灌洗液(BALF)中IL-1β、IL-6和MIP-2水平。用试剂盒检测肺组织中MDA和SOD含量。Western blot检测肺组织中E-cadherin、α-SMA、vimentin、Nrf2、NF-κB p65、p-NF-κB p65、TGF-β1、Smad3和p-Smad3的蛋白表达。结果 与对照组比较,PQ组大鼠肺组织损伤程度,肺纤维化评分,BALF中的IL-1β、IL-6和MIP-2水平,肺组织中MDA含量,α-SMA、vimentin和TGF-β1的蛋白表达水平,NF-κB p65和Smad3蛋白的磷酸化水平均显著升高(P<0.05),而肺组织中SOD含量,E-cadhe...     

MG132抑制TGF-β1诱导的人肺成纤维细胞活化

目的探讨泛素-蛋白酶体抑制剂MG132对转化生长因子β1(TGF-β1)诱导人肺成纤维细胞活化的影响及机制。方法体外培养人胚肺成纤维细胞(MRC-5),随机分为对照组、TGF-β1组(10μg/L)和MG132(0.5μmol/L)处理组。Western blot法检测细胞α-平滑肌肌动蛋白(α-SMA)和Ⅰ型胶原α1(COL1A1)的表达;RT-PCR和Western blot法分别检测细胞Smad7、核转录共抑制因子SnoN、TGF-βI型受体(TβRI)、Smad2和Smad3 mRNA及蛋白的表达。结果与对照组比较,TGF-β1促进了α-SMA和COL1A1蛋白表达(P0.05),MG132抑制了TGF-β1的上述作用(P0.05)。TGF-β1组Smad7和SnoN mRNA表达较对照组增加(P0.05)。TGF-β1组Smad7和SnoN蛋白表达较对照组减少(P0.05),而MG132组Smad7和SnoN蛋白水平较TGF-β1组增加(P0.05)。结论 MG132可能通过阻止Smad7和SnoN蛋白泛素化降解,抑制TGF-β1诱导人肺成纤维细胞活化。     

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。     

肾上腺髓质素通过Smad2/3信号途径抑制TGF-β1刺激的肺成纤维细胞前胶原蛋白的合成

目的观察肾上腺髓质素(AM)对转化生长因子β1(TGF-β1)促进肺成纤维细胞1型前胶原蛋白α1(Col1α1)、3型前胶原蛋白α1(Col3α1)基因表达及Smad2/3通路的影响,探讨AM对TGF-β1促肺成纤维细胞胶原合成作用的机制。方法体外原代培养人胚肺成纤维细胞(HFLF),利用反转录PCR(RT-PCR)观察AM及TGF-β1对HFLF的Col1α1、Col3α1 mRNA表达的影响;Western blot法观察AM及TGF-β1对HFLF磷酸化Smad2/3(p-Smad2/3)蛋白表达的影响。结果 TGF-β1可以刺激HFLF的Col1α1、Col3α1 mRNA和p-Smad2/3蛋白表达,AM则可抑制基础条件下TGF-β1促进的Col3α1 mRNA表达,同时也抑制Smad2/3蛋白的表达。结论 AM可能通过Smad2/3信号转导途径,抑制TGF-β1促进的HFLF前胶原蛋白的合成作用。     

低分子肝素联合乌司他丁治疗急性百草枯中毒大鼠肺纤维化的实验研究

目的探讨低分子肝素联合乌司他丁减轻急性百草枯（PQ）中毒大鼠肺纤维化的可能作用机制。方法55只雄性SD大鼠,随机分成正常对照组（A组）、模型组（B组）、治疗组（C组）;B、C组禁食1h后经口一次灌胃百草枯75mg／kg制作PQ大鼠肺纤维化模型,A组经口一次性注人等量生理盐水;c组造模后皮下注射低分子肝素钠1000U／d,同时腹腔注射乌司他丁10万U,共14d,A、B组给予0．2ml／d生理盐水皮下注射。分别于造模后1、3、7、14、28d测定血清转化生长因子β1（TGFβ1）、基质金属蛋白酶9（MMP-9）含量;并取肺组织做HE染色。结果与A组比较,B组血清TGF-β1第3天始明显升高（P〈0．01）,血清MMP-9于第7天逐渐上升（P〈0．05）,第28天明显升高（P〈0．01）;与B组各相同时间点比较,C组MMP-9水平下降,至第7天差异有统计学意义（P〈0．05）,第28天出现明显下降（P〈0．01）;而血清TGF．131在第14天开始出现明显下降（P〈0．01）。B组于造模后早期即出现肺泡壁增厚,炎症细胞浸润明显,毛细血管充血、水肿等,14d肉眼可见肺表面溃疡形成,镜下可见肺泡间隔成纤维母细胞、肌纤维细胞增生,肺泡塌陷;C组于14d时镜下可见有肺泡壁毛细血管充血,炎性细胞浸润较B组轻,肺纤维化程度也有所减轻。结论低分子肝素联合乌司他丁可减少MMP-9的合成,从而减轻大鼠纤维化程度,其途径可能通过减少TGF．Bl的合成。     

布地奈德对肺纤维化大鼠Smad4、PDGF-A及PAI-1表达的影响

目的:探讨布地奈德(BUD)对肺纤维化大鼠肺组织转化生长因子-β1(TGF-β1)、血小板衍化生长因子-A(PDGF-A)、抗生物皮肤生长因子同源物4母体(Smad4)、纤溶酶原激活物抑制物-1(PAI-1)表达的影响。方法:取健康雌性Wistar大鼠随机分成博莱霉素(BLM)组、生理盐水(NS)组和BUD组,每组15只。NS组气管内灌注NS,BUD组、BLM组气管内灌注BLM,继之0～6 d每天雾化1次,BLM组和NS组雾化吸入NS,BUD组雾化吸入BUD,分别于第7、14、28天处死3组大鼠各5只。用HE、Masson染色观察肺泡炎症和纤维化改变;免疫组化法测定肺组织中TGF-β1、PDGF-A、Smad4、PAI-1的表达。结果:第7、14天,BUD组肺泡炎程度较BLM组减轻(P<0.05);第7、14、28天,BUD组肺纤维化程度均较BLM组减轻(P<0.05)。第7、14、28天,BUD组肺组织中TGF-β1、PDGF-A、Smad4、PAI-1表达较BLM组明显降低(P<0.05)。结论:BUD雾化吸入可降低肺纤维化大鼠肺组织TGF-β1、PDGF-A、Smad4、PAI-1的表达,同时亦可减轻其肺泡炎及肺纤维化程度。     

Rho激酶抑制剂对压力超负荷大鼠心肌纤维化的影响

目的:观察Rho激酶抑制剂法舒地尔对大鼠心肌纤维化的影响。方法:采用腹主动脉缩窄术制备SD大鼠心肌纤维化模型,动脉夹闭4周后,随机分为4组:假手术组(Sham组)、模型组(Model组)、法舒地尔高剂量(FH,30mg/Kg/天)组和法舒地尔低剂量(FL,10mg/Kg/天)组。术后8周末,计算各组大鼠心脏质量指数(HWI)、左室质量指数(LVWI),观察心肌组织HE染色和Masson染色,碱水解法测定心肌组织羟脯氨酸(HYP)含量,免疫组化分析磷酸化的肌球蛋白磷酸酶靶蛋白亚基1(p-MYPT1)、转化生长因子β1(TGF-β1)和结缔组织生长因子(CTGF)水平。结果:与Sham组相比,Model组大鼠LVWI及HYP含量显著升高(P<0.01),心肌细胞排列紊乱,间质大量胶原纤维沉积,心肌组织p-MYPT1水平升高(P<0.01),TGF-β1、CTGF表达升高(P<0.01);与Model组相比,FH组和FL组大鼠LVWI及HYP含量降低(P<0.05),间质胶原蛋白沉积程度减轻,心肌组织p-MYPT1、TGF-β1、CTGF水平均降低(P<0.05或P<0.01)。结论:Rho激酶参与压力超负荷诱导的大鼠心肌纤维化,法舒地尔抑制心肌纤维化进展的作用与TGF-β1和CTGF水平的降低有关。     

穿心莲内酯对肺纤维化大鼠BALF中细胞因子和肺组织Ⅰ、Ⅲ型胶原mRNA表达的影响

目的:探讨穿心莲内酯灌胃对博来霉素(BLM)致肺纤维化大鼠支气管肺泡灌洗液(BALF)中TNF-α、TGF-β1浓度和肺组织Ⅰ、Ⅲ型胶原mRNA表达的影响。方法:取健康雄性SD大鼠90只,随机分为生理盐水(NS)组、BLM组、泼尼松(Pred)组、不同剂量穿心莲内酯组(即穿A组62.5mg/kg、穿B组125 mg/kg、穿C组250 mg/kg),各组大鼠15只,分别气管内灌注BLM(BLM组、Pred组、穿A组、穿B组、穿C组)或NS(NS组)后,每天给予NS(NS组、BLM组)、Pred(Pred组)或穿心莲内酯(穿A组、穿B组、穿C组)灌胃,各组分别于气管内灌注药物后第7、14、28天处死大鼠5只。用HE、Masson染色观察肺泡炎症和纤维化改变;实时荧光定量逆转录-聚合酶链反应检测肺组织Ⅰ、Ⅲ型胶原mRNA表达;酶联免疫吸附试验测定BALF中TNF-α、TGF-β1浓度;同时监测肾功能指标血尿素氮(BUN)、肌酐(Cr)及肝功能指标血丙氨酸氨基转移酶(ALT)、天冬氨酸氨基转移酶(AST)。结果:肝肾功能监测显示:不同剂量穿心莲内酯组、NS组、BLM组、Pred组所监测的AST、ALT、BUN、Cr比较,差异无统计学意义(P>0.05)。NS组大鼠肺组织未发现肺泡间隔水肿、炎性细胞浸润和纤维化形成。BLM组第7天时肺泡腔内可见大量炎性细胞浸润,第14天时肺泡炎仍存在,但炎症细胞明显减少,肺泡间隔内成纤维细胞明显增多,肺泡结构破坏,肺泡隔增宽,第28天时炎症较前减轻,肺纤维化程度加重,部分肺泡腔消失,形成严重纤维化。穿A组病理形态改变与BLM组相似。Pred组、穿B组、穿C组大鼠第7天有较多的炎症细胞浸润及局部聚积,第14天和第28天的纤维化病理改变均较BLM组、穿A组明显减轻。NS组各个时间点BALF中TGF-β1、TNF-α含量均明显低于同时间点BLM组、Pred组、穿A组、穿B组、穿C组BALF中的浓度(P<0.05)。BLM组3个时间点BALF中TGF-β1、TNF-α含量较Pred组、穿B、穿C组高(P<0.05)。与BLM组比较,穿A组BALF中TGF-β1、TNF-α含量无统计学意义。NS组各个时间点肺组织Ⅰ、Ⅲ型胶原mRNA表达均明显低于同时间点BLM组、Pred组、穿A组、穿B组、穿C组肺组织中的表达(P<0.05)。BLM组3个时间点Ⅰ、Ⅲ型胶原mRNA表达较Pred组、穿B组、穿C组高(P<0.05)。与BLM组比较,穿A组肺组织Ⅰ、Ⅲ型胶原mRNA表达无统计学差异。结论:穿心莲内酯灌胃可减轻BLM致肺纤维化大鼠肺泡炎和肺纤维化程度,降低肺组织Ⅰ、Ⅲ型胶原mRNA表达,降低BALF中TNF-α、TGF-β1浓度,且对肝肾无明显毒副作用。     

Combination Therapy with Pirfenidone plus Prednisolone Ameliorates Paraquat-Induced Pulmonary Fibrosis

Pirfenidone is known to slow the decline in vital capacity and increase survival in idiopathic pulmonary fibrosis (IPF). Besides, administration of glucocorticoids, e.g., prednisolone has been the conventional strategy to the treatment of patients with this disease, although their efficacy is under debate. Since multiple coactivated pathways are involved in the pathogenesis of IPF, combination therapy is a foundation strategy to cover many more synergetic mechanisms and increase response. The aim of the present study was to compare the therapeutic efficacy of prednisolone plus pirfenidone with pirfenidone alone in PQ-induced lung fibrosis. After development of PQ-induced lung fibrosis, pirfenidone, prednisolone, and their combination were administered for 14 consecutive days. Lung pathological lesions, along with increased hydroxyproline were determined in the paraquat group. Paraquat also caused oxidative stress and increasing the proinflammatory and profibrotic gene expression. Pirfenidone attenuated the PQ-induced pulmonary fibrosis from the analysis of antioxidant enzymes but prednisolone had no such effect. Co-treatment with pirfenidone and prednisolone suppressed lung hydroxyproline content, TGF-β1, and TNF-α; however, prednisolone alone could not suppress pulmonary fibrosis which was significantly suppressed only by pirfenidone. Pirfenidone also suppressed the increase in MMP-2 and TIMP-1 induced by PQ. All of these effects were exaggerated when pirfenidone coadministered with prednisolone. These findings suggest that pirfenidone exerts its antifibrotic effect through regulation of hydroxyproline content, oxidative stress and proinflammatory and profibrotic gene expression during the development of PQ-induced pulmonary fibrosis in rats and combination therapy with prednisolone can represent more potent therapeutic effects.     

Immunohistochemical study of metalloproteinases and their tissue inhibitors in the lungs of patients with diffuse alveolar damage and idiopathic pulmonary fibrosis.

Immunohistochemical and confocal microscopic studies of the localization of matrix metalloproteinases (MMPs), their tissue inhibitors (TIMPs), and type IV collagen were made in lung tissues from patients with normal pulmonary histology (n = 3), diffuse alveolar damage (n = 14), and idiopathic pulmonary fibrosis (n = 12). Pretreatment with pepsin revealed otherwise undetectable MMP- and TIMP-immunoreactive sites. In normal lung, MMP-2, MMP-9, TIMP-1, and TIMP-2 were localized in ciliated cells, endothelial cells, pneumocytes, macrophages, and smooth muscle cells; fibroblasts showed a strong reaction only for MMP-2. Only TIMP-2 showed co-localization with type IV collagen. Myofibroblasts and epithelial cells expressed increased reactivity for MMPs and TIMPs in both disorders. The reactivities for MMPs and TIMPs were stronger in diffuse alveolar damage. MMP-2 showed focal co-localization in capillary endothelial and disrupted epithelial basement membranes, suggesting activation of collagenolysis. A protective effect against this lysis was suggested by the extensive co-localization of TIMP-2 with type IV collagen and fibrillar collagens. Alveolar buds showed increased reactivity for MMPs and TIMPs in their lining epithelial cells, myofibroblasts, and their basement membranes; however, their matrices were mostly unreactive. These findings emphasize the complexity of the roles of MMPs and TIMPs in collagen turnover in diffuse alvcolar damage and idiopathic pulmonary fibrosis.     

Absence of Thy-1 results in TGF-β induced MMP-9 expression and confers a profibrotic phenotype to human lung fibroblasts

Fibroblasts differ in a variety of phenotypic features, including the expression of Thy-1 a glycophosphatidylinositol-linked glycoprotein. Fibroblasts in idiopathic pulmonary fibrosis (IPF) are Thy-1 negative, whereas most fibroblasts from normal lungs are Thy-1 positive. However, the functional consequences of the absence of Thy-1 are not fully understood. We analyzed the expression of Thy-1 in several primary fibroblasts lines derived from IPF, hypersensitivity pneumonitis (HP), and normal human lungs. We found that a high proportion, independently of their origin, expressed Thy-1 in vitro. We identified a primary culture of HP fibroblasts, which did not express Thy-1, and compared several functional activities between Thy-1 (-) and Thy-1 (+) fibroblasts. Thy-1 (-) fibroblasts were smaller (length: 41.3±20.8?μ versus 83.1±40 μ), showed increased proliferative capacity and enhanced PDGF-induced transmigration through collagen I (59.9% versus 42.2% over control under basal conditions, P<0.01). Likewise, Thy-1 (-) fibroblasts either spontaneously or after TGF-β stimulation demonstrated stronger contraction of collagen matrices (eg, 0.17±0.03 versus 0.6±0.05 cm2 after TGF-β stimulation at 24 h; P<0.01). Thy-1 (-) lung fibroblasts stimulated with TGF-β1 expressed MMP-9, an enzyme that is usually not produced by lung fibroblasts. TGFβ-induced MMP-9 expression was reversible upon re-expression of Thy-1 after transfection with full-length Thy-1. β-glycan, a TGF-β receptor antagonist abolished MMP-9 expression. TGF-β1-induced MMP-9 in Thy-1 (-) fibroblasts depended on the activation of ERK1/2 signaling pathway. Finally, we demonstrated that fibroblasts from IPF fibroblastic foci, which do not express Thy-1 exhibit strong staining for immunoreactive MMP-9 protein in vivo. These findings indicate that loss of Thy-1 in human lung fibroblasts induces a fibrogenic phenotype.     

Immunohistochemical localization of transforming growth factor-β1 in the lungs of patients with systemic sclerosis, cryptogenic fibrosing alveolitis and other lung disorders

To study the role of transforming growth factor-β₁ (TGF-β₁) in the pathogenesis of pulmonary fibrosis we have examined lung biopsies from nine patients with systemic sclerosis and interstitial lung disease, eight with ‘lone’ cryptogenic fibrosing alveolitis, two with cystic fibrosis, two with extrinsic allergic alveolitis, two with Langerhans' cell histiocytosis, one with lymphangioleiomyomatosis, one with giant cell interstitial pneumonia, and one adenocarcinoma of the lung. In cryptogenic fibrosing alveolitis, both ‘lone’ and associated with systemic sclerosis, alveolar macrophages, bronchial epithelium and hyperplastic type II pneumonocytes expressed intracellular TGF-β₁. Extracellular TGF-β₁ was found in the fibrous tissue immediately beneath the bronchial and hyperplastic alveolar epithelium. In normal lung, however, the alveolar epithelium and alveolar interstitium were negative for both forms of TGF-β₁. There was strong expression of TGF-β₁ in hyperplastic mesothelium and its underlying connective tissue and in Langerhans' cells in the two cases of histiocytosis. In the organizing pneumonia in cystic fibrosis, the intraalveolar buds of granulation tissue reacted strongly for the extracellular form of TGF-β₁ and the overlying hyperplastic epithelium expressed the intracellular form. In lymphangioleiomyomatosis, the aberrant smooth muscle cells strongly expressed intracellular TGF-β₁ and the extracellular form was expressed in the adjacent connective tissue. In giant cell interstitial pneumonia, the numerous alveolar macrophages, including the multinucleate forms, expressed intracellular TGF-β₁, as did the hyperplastic alveolar epithelium. Adenocarcinoma cells expressed the intracellular form of TGF-β₁ strongly and the extracellular form was evident in the tumour stroma. The strong expression of TGF-β₁ in hyperplastic type II pneumonocytes and the fibrosis underlying these cells suggests that TGF-β₁ produced during alveolar epithelial regeneration may play a part in several forms of pulmonary fibrosis.     

丹参素干预对肺纤维化大鼠TGF-β1/Smads信号通路的影响

 目的： 探讨丹参素对博莱霉素所致大鼠肺纤维化的防治作用及其可能机制。方法： SD大鼠经气管内滴注博莱霉素诱导肺间质纤维化,随后分别腹腔内注射丹参素15 mg·kg-1·d-1(DA组)、地塞米松1 mg·kg-1·d-1(DXM组)和生理盐水2 mL·d-1 (BLM组)进行干预,正常对照组(NC组)气管内滴注和腹腔内注射均用生理盐水。于造模后第28天处死所有大鼠,通过苏木精-伊红(HE)染色和Masson染色来评价治疗效果;免疫组化技术检测肺组织α-平滑肌肌动蛋白(α-SMA)表达;实时荧光定量PCR测定转化生长因子β1（TGF-β1）、Smad3及Smad7 mRNA的表达。结果： DA组与BLM组相比,肺泡炎症及肺纤维化程度均明显减轻,肺组织α-SMA表达明显减少,肺组织TGF-β1和Smad3 mRNA表达明显减少,Smad7 mRNA明显增多。结论： 丹参素早期应用可减轻博来霉素诱导的大鼠肺纤维化,可能通过抑制TGF-β1、Smad3 mRNA和促进Smad7 mRNA的表达而实现。