三氧化二砷对博莱霉素致大鼠肺纤维化的影响及其作用机制

目的:观察三氧化二砷对博莱霉素致大鼠肺纤维化的影响及可能的作用机制。方法:SD大鼠气管内滴注博莱霉素诱导肺纤维化,腹腔内分别注射三氧化二砷(治疗组)、地塞米松(激素组)、生理盐水(模型组)进行干预。各组动物再按造模后开始干预的时间不同分为14d和28d开始干预2个亚组,每个亚组再按观察时间不同分为14d、28d和56d3个观察组。观察大鼠中位生存时间、肺组织羟脯氨酸含量、肺泡炎和肺纤维化程度(HE染色)、肺组织胶原定量分析(Masson染色)等指标来评价药物干预效果,并采用脱氧核糖核苷酸末端转移酶介导的缺口末端标记法(TUNEL法)检测肺组织凋亡指数。同时对肺组织转化生长因子-β1(TGF-β1)、干扰素-γ(IFN-γ)、基质金属蛋白酶-9(MMP-9)、金属蛋白酶组织抑制物-1(TIMP-1)免疫组化染色结果进行定量分析。结果:(1)生存时间观察:造模后14d开始干预的模型组、治疗组和激素组的中位生存时间分别为30d、57d和19d(P0.01);而造模后28d开始干预的各组的中位生存时间为40d、58d和34d(P0.05)。(2)肺纤维化的比较:各治疗组大鼠的羟脯氨酸含量与模型组相比均有下降趋势。各治疗组的肺泡炎和肺纤维化程度均轻于模型组。与模型组相比,各治疗组的胶原面积均小于模型组。(3)肺组织凋亡指数的比较:与模型组相比,14d开始干预并观察14d、28d组和28d开始干预并观察14d组的治疗组大鼠凋亡指数明显升高。(4)14d开始干预的各组的细胞因子比较:各治疗组的肺组织中转化生长因子-β1(TGF-β1)免疫组化染色的平均光密度均低于相应模型组。治疗组中观察28d和56d小组的肺组织中干扰素-γ(IFN-γ)免疫组化染色的平均光密度均高于模型组。各治疗组的肺组织中基质金属蛋白酶-9(MMP-9)免疫组化染色平均光密度与模型组区别不明显。与模型组比较,各治疗组的肺组织中金属蛋白酶组织抑制物-1(TIMP-1)免疫组化染色平均光密度明显降低。结论:三氧化二砷能够减轻博莱霉素诱导的大鼠肺纤维化,其机制可能与诱导肺组织细胞凋亡增加有关。     

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。     

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。     

替普瑞酮诱导肺纤维化大鼠肺HSP70表达及干预肺纤维化的研究

目的:研究替普瑞酮(GGA)对博莱霉素(BLM)诱导的肺纤维化大鼠肺组织HSP70表达的影响及对大鼠肺纤维化的干预作用。方法:SD大鼠30只,随机分为假手术组(SO)、模型组(M)和替普瑞酮组(GGA)。M组和GGA组大鼠气管内一次性注射BLM 5 mg/kg,SO组大鼠气管内注射等体积的生理盐水。造模后第1天开始隔天灌胃给予GGA,持续到处死动物的前1天,模型组灌服等体积的生理盐水。记录大鼠每日体重,造模后第28天时处死大鼠,测定肺纤维化大鼠的肺系数、肺组织内HSP70表达及羟脯氨酸(HYP)的含量,观察肺组织病理改变。结果:GGA能提高博莱霉素处理后大鼠肺组织HSP70的表达(P<0.01);与M组相比,大鼠体重下降得到明显恢复(P<0.01),而肺组织的肺系数和羟脯氨酸(HYP)含量则明显降低(P<0.05),病理结果显示肺泡内结构完整,未出现类似M组肺组织实变现象,肺纤维化程度较轻。结论:替普瑞酮能诱导BLM肺纤维化模型大鼠肺组织HSP70表达,减轻肺纤维化程度。     

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。     

纤溶酶原激活物抑制剂1 siRNA对大鼠肺纤维化的治疗作用

 目的： 观察纤溶酶原激活物抑制剂1 （PAI-1）siRNA对博来霉素(BLM)诱导的大鼠肺纤维化的治疗作用,并初步探讨其机制。方法： 72只Wister大鼠分为4组,即对照组（control组）、BLM组、BLM+非特异 siRNA 组(BLM+N组)和BLM+PAI-1 siRNA组(BLM+P组)。BLM 5 mg/kg气管内滴入制作肺纤维化模型,control组注入等体积的生理盐水。造模后,于局麻下BLM+P组每周2次气管内注入PAI-1 siRNA 7.5 nmol (0.2 mL);BLM+N组注入相同剂量的非特异siRNA;control组和BLM组注入等体积的生理盐水,28 d共给药8次。分别于第7 d、14 d和28 d每组处死6只,左肺行肺泡灌洗测定PAI-1活性,右中叶肺组织RT-PCR法检测Ⅲ型胶原、α-平滑肌肌动蛋白（α-SMA）和金属蛋白酶组织抑制物1（TIMP-1）的mRNA表达。结果： 造模后,7 d、14 d和28 d肺泡灌洗液中PAI-1活性持续升高,每周2次气管内注入PAI-1 siRNA可以使肺泡灌洗液中PAI-1的活性降低,与同一时点BLM组比较有明显差异（均P<0.05）;模型组7 d、14 d和28 d  Ⅲ型胶原、α-SMA和TIMP-1的mRNA表达明显增高,BLM+P组3个时点Ⅲ型胶原、α-SMA和TIMP-1的mRNA表达明显减少,分别与同一时点BLM组比较有明显差异（均P<0.05）。结论： 每周2次气管内给予PAI-1 siRNA可以持续减少PAI-1表达。PAI-1 siRNA不但直接抑制肺纤维化进展,而且可以打破基质金属蛋白酶及组织抑制因子之间的平衡。     

FGF-21和Nrf2对博莱霉素诱导的小鼠肺纤维化的影响

目的:研究成纤维细胞生长因子21(FGF-21)对博莱霉素(BLM)诱导的小鼠肺纤维化炎症应答及氧化应激的影响,并探讨其抗肺纤维化的作用机制。方法:建立BLM诱导的小鼠肺纤维化的模型,40只小鼠随机分为对照组、BLM组及FGF-21(1、2及5 mg/kg)+BLM组。Western blot检测I型胶原蛋白(collagen I)、纤连蛋白(fibronectin)和核因子E2相关因子2(Nrf2)蛋白表达水平。DCFH-DA染色检测活性氧簇(ROS)的生成。ELISA用于测定肺组织炎症因子的表达。试剂盒检测各组小鼠肺组织中的丙二醛(MDA)含量、超氧化物歧化酶(SOD)活性、谷胱甘肽过氧化物酶(GPx)活性和羟脯氨酸(HYP)含量。结果:FGF-21处理显著降低BLM诱导的肺组织炎症介质肿瘤坏死因子α、白细胞介素1β和白细胞介素6的表达水平,减少ROS及MDA的含量,并增加抗氧化酶系统SOD和GPx的活性(P 0. 05)。同时,FGF-21下调BLM诱导的collagen I和fibronectin,并减少TGF-β1及HYP的含量。Nrf2沉默能够逆转FGF-21的抗纤维化作用。结论:FGF-21通过激活Nrf2信号抑制炎症应答进程,减轻氧化损伤,减少细胞外基质沉积,从而缓解BLM诱导的肺纤维化。这可能为肺间质纤维化治疗提供新的靶点。     

Protective roles of pulmonary rehabilitation mixture in experimental pulmonary fibrosis in vitro and in vivo

Abnormal high mobility group protein B1 (HMGB1) activation is involved in the pathogenesis of pulmonary fibrosis. Pulmonary rehabilitation mixture (PRM), which combines extracts from eight traditional Chinese medicines, has very good lung protection in clinical use. However, it is not known if PRM has anti-fibrotic activity. In this study, we investigated the effects of PRM on transforming growth factor-β1 (TGF-β1)-mediated and bleomycin (BLM)-induced pulmonary fibrosis in vitro and in vivo. The effects of PRM on TGF-β1-mediated epithelial-mesenchymal transition (EMT) in A549 cells, on the proliferation of human lung fibroblasts (HLF-1) in vitro, and on BLM-induced pulmonary fibrosis in vivo were investigated. PRM treatment resulted in a reduction of EMT in A549 cells that was associated with attenuating an increase of vimentin and a decrease of E-cadherin. PRM inhibited the proliferation of HLF-1 at an IC₅₀ of 0.51 µg/mL. PRM ameliorated BLM-induced pulmonary fibrosis in rats, with reduction of histopathological scores and collagen deposition, and a decrease in α-smooth muscle actin (α-SMA) and HMGB1 expression. An increase in receptor for advanced glycation end-product (RAGE) expression was found in BLM-instilled lungs. PRM significantly decreased EMT and prevented pulmonary fibrosis through decreasing HMGB1 and regulating RAGE in vitro and in vivo. PRM inhibited TGF-β1-induced EMT via decreased HMGB1 and vimentin and increased RAGE and E-cadherin levels. In summary, PRM prevented experimental pulmonary fibrosis by modulating the HMGB1/RAGE pathway.     

甘草酸对博莱霉素诱导的实验性肺纤维化的干预作用

目的:探讨甘草酸(GA)对博莱霉素(BLM)诱导的小鼠肺纤维化的干预作用及其可能机制。方法:将160只雄性C57BL/6J小鼠随机分为生理盐水(NS)组、BLM组、BLM+NS组和BLM+GA组。通过口咽气管吸入法吸入博莱霉素(2.5 mg/kg)建立实验性肺纤维化模型,BLM+GA组及BLM+NS组每天给予40 mg/kg甘草酸或等体积的生理盐水灌胃,于术后第3、7、14、21天取材。采用HE染色和Masson染色观察肺组织病理学变化及纤维化程度,采用流式细胞术检测循环单核细胞和肺泡巨噬细胞的亚群比例变化,采用RT-qPCR检测肺组织中转化生长因子β1(TGF-β1)mRNA的表达水平,采用碱水解法检测肺组织中羟脯氨酸(HYP)含量。结果:与NS组相比,BLM组和BLM+NS组肺组织的炎症浸润及胶原含量明显增多,实验性肺纤维化模型制备成功。与BLM+NS组相比:BLM+GA组肺组织的炎症细胞浸润及胶原纤维沉积较少;第3、7天的Ly6C~(hi)单核细胞亚群比例和第7、14天肺泡巨噬细胞M2表型比例显著降低(P0.01);肺组织TGF-β1 mRNA表达量和HYP含量显著降低(P0.01)。结论:GA可以减轻博莱霉素诱导的小鼠肺组织的炎症反应和胶原纤维沉积,可能与GA对单核巨噬细胞的表型偏移和调控以及肺组织TGF-β1的表达下调有关。     

博莱霉素诱导小鼠肺间质纤维化造模方式的选择

目的:建立博莱霉素导致肺间质纤维化小鼠动物模型,比较不同给药方式的成模差异。方法:利用8周龄雄性ICR小鼠,①随机分为腹腔给药组(P组)、气管内给药组(I组)、阴性对照组(C组),分别经腹腔注射BLM 40 mg/kg 5次、气管内滴入BLM 5 mg/kg 1次或气管内滴入生理盐水50μl。分别于14、28、40天处死,②小鼠随机分为4组,分别经腹腔注射BLM 40mg/kg3、4、5次或经腹腔给予生理盐水200μl。分别于28、40天处死。观察小鼠体重、咳嗽、挠鼻症状、肺系数及肺组织病理改变。结果:给予博莱霉素后①小鼠的体重均下降并出现咳嗽及挠鼻等呼吸障碍症状;处置后第14、28及40天处死小鼠,计算肺系数,P组较I组肺系数高;处死小鼠后,P组和I组小鼠均形成广泛、稳定的间质纤维化病理改变,P组主要分布在胸膜下及血管周围,而I组主要分布在肺门和支气管周围。P组较I组肺纤维化病理评分高。②不同腹腔给药次数模型小鼠体重变化以5次给药对体重影响最大;计算肺系数以给药5次肺系数变化最大。上述模型均成功建立。通过比较生存率、呼吸困难症状、组织病理变化等指标,选出腹腔给药5次相对于给药3次及4次为更好的造模方式。结论:利用BLM腹腔注射和气管内滴入制备了肺间质纤维化动物模型,纤维化形成的部位存在着一定的差异,腹腔给药5次方法制备肺间质纤维化模型的成功率更佳。     

Direct thrombin inhibition reduces lung collagen, accumulation, and connective tissue growth factor mRNA levels in bleomycin-induced pulmonary fibrosis

Dramatic activation of the coagulation cascade has been extensively documented for pulmonary fibrosis associated with acute and chronic lung injury. In addition to its role in hemostasis, thrombin exerts profibrotic effects via activation of the major thrombin receptor, protease-activated receptor-1. In this study, we examined the effect of the direct thrombin inhibitor, UK-156406 on fibroblast responses in vitro and on bleomycin-induced pulmonary fibrosis in rats. UK-156406 significantly inhibited thrombin-induced fibroblast proliferation, procollagen production, and connective tissue growth factor (CTGF) mRNA levels when used at equimolar concentration to the protease. Thrombin levels in bronchoalveolar lavage fluid and expression of thrombin and protease-activated receptor-1 in lung tissue were increased after intratracheal instillation of bleomycin. The characteristic doubling in lung collagen in bleomycin-treated animals (38.4 +/- 2.0 mg versus 17.1 +/- 1.4 mg, P < 0.01) was preceded by significant elevations in alpha1(I) procollagen and CTGF mRNA levels (3.0 +/- 0.4-fold and 6.3 +/- 0.4-fold respectively, (P < 0.01), and total inflammatory cell number. UK-156406, administered at an anticoagulant dose, attenuated lung collagen accumulation in response to bleomycin by 35 +/- 12% (P < 0.05), inhibited alpha1(I) procollagen and CTGF mRNA levels by 50% and 35%, respectively (P < 0.05), but had no effect on inflammatory cell recruitment. This is the first report showing that direct thrombin inhibition abrogates lung collagen accumulation in bleomycin-induced pulmonary fibrosis.     

盐皮质激素受体在博来霉素诱导的实验性肺纤维化中的作用*

 目的：研究盐皮质激素受体（MR）在博来霉素诱导的实验性肺纤维化进展过程中的作用及机制。方法：将126只6～8周龄雄性C57BL/6小鼠随机分为对照组、博来霉素组和MR阻断剂螺内酯干预组,气管内一次性滴注博来霉素(2.5 mg/kg)溶液建立实验性小鼠肺纤维化模型,螺内酯干预组每天按螺内酯20 mg/kg经灌胃给药。于术后12 h、1 d、2 d、3 d、7 d、14 d和28 d处死小鼠,采用HE染色和Masson染色观察肺组织病理学变化及纤维化程度,采用real-time PCR检测各组肺组织中胶原1(Col1)、Col3、转化生长因子β(TGF-β)、单核细胞趋化蛋白1（MCP-1）及MR mRNA的表达水平。结果：（1）与对照组小鼠相比,博来霉素组及螺内酯干预组小鼠在滴注博来霉素后经历了典型的急性炎症期（12 h～3 d）、纤维化进展期（14 d）和纤维化晚期（28 d）。阻断MR下调早期炎症反应并减轻了纤维化程度。（2）螺内酯干预可以有效降低MR mRNA表达水平;阻断MR在急性炎症期显著下调MCP-1 mRNA的表达,在14 d显著下调TGF-β、Col1和Col3 mRNA表达水平。结论：(1）阻断MR可以明显减轻博来霉素诱导的肺纤维化程度;(2）阻断MR可能通过在急性炎症期调节MCP-1和TGF-β的表达,减轻炎症反应,并在纤维化进展期,下调TGF-β的表达,从而抑制肺纤维化的进展。     

Rat alveolar myofibroblasts acquire alpha-smooth muscle actin expression during bleomycin-induced pulmonary fibrosis.

The majority of fibroblasts in alveolar septa are characterized by the presence of cytoplasmic bundles of microfilaments that contain cytoplasmic actin isoforms; these cells have been named contractile interstitial cells or V-type myofibroblasts. In the rat, they express desmin as intermediate filament protein. In this study, we explored the possibility that modulation and replication of such septal fibroblasts result in the appearance of alpha-smooth muscle (alpha-SM) actin-positive myofibroblasts, typical of lung fibrosis. Experimental pulmonary fibrosis was produced by a unique intratracheal instillation of bleomycin to 28 rats. Eight additional rats used as controls received the equivalent volume of saline. Paraffin and frozen sections of lungs were examined at days 1, 3, 5 and 7 after treatment. Microfilaments and intermediate filaments were stained using antibodies against total actin, alpha-SM actin, desmin, vimentin, keratin, and SM myosin. Electron microscopic labeling of desmin and alpha-SM actin using immunogold technique was done on Lowicryl K4M resin-embedded specimens. alpha-SM actin appeared in desmin-positive alveolar fibroblasts as early as 24 hours after intratracheal bleomycin instillation; the modulation of alpha-SM actin in these cells was preceded by a lymphomonocytic infiltration of alveolar septa. Twenty-four hours to 3 days after bleomycin administration, a proliferation of alveolar myofibroblasts occurred. Fibrosis with laying down of collagen fibers took place after the above mentioned cellular modifications. Our results support the view that septal fibroblastic cells can modulate into typical alpha-SM actin-containing myofibroblasts during experimental bleomycin-induced pulmonary fibrosis. In such a modulation a possible role of cytokines, particularly of transforming growth factor-beta, is considered.     

Keratinocyte growth factor gene transduction ameliorates pulmonary fibrosis induced by bleomycin in mice

Pulmonary fibrosis has high rates of mortality and morbidity, but there is no established therapy at present. We demonstrate here that bleomycin-induced pulmonary fibrosis in mice is ameliorated by intratracheal administration of keratinocyte growth factor (KGF)-expressing adenovirus vector. Progressive pulmonary fibrosis was created by continuous subcutaneous administration of 120 mg/kg of bleomycin subcutaneously using an osmotic pump twice from Day 1 to 7 and Day 29 to 35. The mice initially exhibited subpleural fibrosis and then exhibited advanced fibrosis in the parenchyma of the lungs. These histopathological changes were accompanied by reduced lung compliance (0.041 ± 0.011 versus 0.097 ± 0.004; P < 0.001), reduced messenger expression of surfactant proteins, and reduced KGF messenger expression in the lungs at 4 weeks compared with naive group. Intratracheal instillation of Ad-KGF at 1 week after the first administration of bleomycin increased KGF mRNA expression in the lungs compared with the fibrosis-induced mice that received saline alone. The phenotype was associated with alveolar epithelial cell proliferation, increased pulmonary compliance (0.062 ± 0.005 versus 0.041 ± 0.011; P = 0.023), and decreased mortality (survival rate on Day 56: 68.8% versus 0%; P = 0.002), compared with mice receiving only the saline vehicle. These observations suggest the therapeutic utility of a KGF-expressing adenoviral vector for pulmonary fibrosis.     

Bleomycin-induced pulmonary fibrosis in rat is associated with increased expression of collagen-binding heat shock protein (HSP) 47

 Increased accumulation of collagens in extracellular matrix (ECM) is mainly responsible for bleomycin-induced pulmonary fibrosis in rats. This study was designed to assess whether increased collagen accumulation in bleomycin-induced pulmonary fibrosis is associated with heat shock protein (HSP) 47, a molecular chaperone for collagen biosynthesis. We investigated the expression of type I and type III collagens and HSP47 in bleomycin-induced pulmonary fibrosis. Fifteen male Wistar rats were divided into two groups; group I: bleomycin-induced pulmonary fibrosis; group II: PBS-treated age-matched control rats. Pulmonary fibrosis was induced by injecting a single dose of bleomycin sulphate (5 U/kg body weight) intratracheally. Three bleomycin-treated rats and two age-matched control rats were sacrificed at the end of each of the 1st, 2nd and 4th weeks of the experiment. In bleomycin-treated rats, histological examination revealed pulmonary fibrosis, which increased with time. Increased type I and type III collagen desposition was observed in the lungs of all the bleomycin-treated rats. Weak immunostaining of HSP47 was noted in the control lungs. In contrast, strong immunostaining for HSP47 was seen in all the bleomycin-treated fibrotic lungs. In addition, increased numbers of phenotypically altered myofibroblasts (α-smooth muscle actin immunopositive) and fibroblast (vimentin immunopositive) were seen in bleomycin-treated lungs and found to express HSP47. Parallel increase of collagens and their molecular chaperone HSP47 expression was found in the bleomycin-treated lungs, and their co-localization could be detected by double immunostaining. Overexpression of HSP47 may play a significant part in the excessive assembly of collagens and could contribute in this way to the fibrosis found in bleomycin-treated rat lungs. Received: 30 April 1997 / Accepted: 17 July 1997     

吉非替尼抑制博莱霉素诱导的小鼠肺纤维化

目的:观察吉非替尼对博莱霉素诱导的小鼠肺纤维化的抑制作用。方法:将40只SPF级雌性BALB/c小鼠分为4组:对照组(气管滴入生理盐水)、单纯口服吉非替尼组(吉非替尼灌胃200 mg/kg)、纤维化组(气管滴入博莱霉素3 mg/kg)、纤维化吉非替尼干预组(气管滴入博莱霉素+吉非替尼灌胃20 mg/kg)。实验第14 d杀鼠取肺,左肺石蜡切片行HE染色与Masson染色,免疫组化检测总表皮生长因子受体(EGFR)及磷酸化EG-FR;取右肺检测羟脯氨酸含量。结果:纤维化吉非替尼干预组肺病理损伤较纤维化组减轻,气道上皮下胶原沉积及肺羟脯氨酸含量减少(P0.05),气道上皮及肺间质细胞磷酸化EGFR表达评分下降(P0.05)。单纯口服吉非替尼组小鼠气道上皮下未见明显胶原沉积,肺羟脯氨酸含量及磷酸化EGFR表达评分与对照组相比无显著差异(P0.05)。结论:吉非替尼灌胃能显著抑制博莱霉素诱导的小鼠肺纤维化,大剂量(200 mg/kg)吉非替尼灌胃未引起明显肺纤维化。     

依那西普抑制博来霉素诱导的小鼠肺纤维化

 目的：观察肿瘤坏死因子 α(TNF-α)拮抗剂依那西普对博来霉素诱导的肺纤维化小鼠的抑制纤维化作用,并探讨依那西普治疗肺纤维化的可能机制。方法：将45只SPF级雌性昆明小鼠随机分为3组：对照组（气管内雾化生理盐水）、纤维化组（气管内博来霉素3 mg/kg溶于100 μL生理盐水内雾化）和依那西普干预组（气管内雾化博来霉素后,4 mg/kg依那西普溶于100 μL生理盐水内腹腔注射,每3 d注射1次）。处理后第28 d收集样本,小鼠左肺置于10%中性甲醛固定,石蜡包埋切片后行HE与Masson染色;右肺碱水解法检测组织羟脯氨酸(HYP)的含量;酶联免疫法检测血清TNF-α和转化生长因子 β（TGF-β）的含量;提取肺组织总蛋白,Western blotting 检测磷酸化ERK1/2、JNK和p38的表达。结果：依那西普干预组肺组织病理损伤及气道上皮下胶原沉积较纤维化组减轻,肺叶炎症损伤评分和纤维化评分明显下降（均P<0.01）,肺组织HYP含量显著降低（P<0.05）,血清TNF-α 和TGF-β的浓度明显减少（均P<0.01）,肺组织ERK1/2、JNK和p38蛋白的磷酸化水平也显著下降（P<0.01,P<0.05,P<0.01）。结论：依那西普能显著下调TNF-α 和TGF-β的水平,从而抑制ERK1/2、JNK和p38的活化,缓解博来霉素诱导的小鼠肺纤维化病变。     

丙戊酸钠减轻博莱霉素致大鼠肺纤维化

目的:探讨丙戊酸钠在博莱霉素诱导的肺纤维化中的作用及机制。方法:42只大鼠随机分为正常对照组、模型组和治疗组。造模采用博来霉素5 mg/kg气管内注射,自造模14 d开始分别采用生理盐水(0.5m L/d)、丙戊酸钠(300 mg·kg-1·d-1)和地塞米松(0.6 mg·kg-1·d-1)腹腔内注射治疗14 d。模型组分别在造模后14和、28 d处死。治疗组在造模后28 d处死。然后通过HE染色、Masson染色、羟脯氨酸(HYP)检测和Western blotting检测α-平滑肌肌动蛋白(α-SMA)及E-钙黏蛋白(E-cadherin)表达的变化,综合分析丙戊酸钠对肺纤维化发展的干预作用。结果:HE染色显示丙戊酸钠治疗组的肺泡结构、肺间质的形态优于生理盐水组和地塞米松治疗组。Masson染色及HYP检测用于衡量肺组织内胶原的分布及含量,可见丙戊酸钠治疗组肺组织内胶原的分布及含量均显著低于地塞米松治疗组及生理盐水组。丙戊酸钠可以降低α-SMA的表达,同时上调上皮标志性蛋白E-cadherin的表达。结论:丙戊酸钠可以通过减少胶原的表达与分布及下调间充质蛋白α-SMA,同时上调上皮蛋白E-cadherin的表达从而减轻博来霉素诱导大鼠肺纤维化。