肌成纤维细胞在支气管哮喘气道结构重塑中的作用

肌成纤维细胞兼具成纤维细胞和平滑肌细胞的某些特征,来源于局部细胞的增殖,其他细胞的转化及循环中前体细胞的定植,在疤痕形成、肺纤维化等病理过程中发挥重要作用。研究显示其受支气管哮喘相关炎症因子及介质的调控,通过分泌细胞外基质及迁移功能而参与支气管哮喘气道重塑。深入了解肌成纤维细胞在支气管哮喘气道重塑中的作用有助于建立防治气道重塑的新策略。     

肺成纤维细胞参与支气管哮喘气道重塑研究进展

支气管哮喘( 哮喘) 气道重塑可引起不可逆性气道阻塞和顽固性气道高反应性。哮喘患者气道上皮下肺成纤 维增殖、转化为肌成纤维细胞及大量细胞外基质(ECM) 合成是导致上皮下纤维化的主要机制之一。近年来,上皮下 肺成纤维细胞在哮喘气道重塑中的作用越来越受关注,研究也发现很多哮喘治疗药物也对肺成纤维细胞有一定的 影响。明确药物对肺成纤维细胞的影响,对哮喘气道重塑的治疗有重要的意义。     

转化生长因子β与支气管哮喘气道重塑

转化生长因子β(TGFB)具有强烈的致纤维化作用,支气管哮喘发病过程中,TGFB表达增高,气道TGFB/EGF(表皮生长因子)失衡,引起成纤维细胞、肌成纤维细胞增生,细胞外基质合成增加、降解减少,导致气道重塑。     

转化生长因子β与支气管哮喘气道重塑

转化生长因子β（TGFB）具有强烈的致纤维化作用,支气管哮喘发病过程中,TGFB表达增高,气道TGFB／EGF（表皮生长因子）失衡,引起成纤维细胞、肌成纤维细胞增生,细胞外基质合成增加、降解减少,导致气道重塑。     

气道上皮损伤与支气管哮喘

支气管哮喘发病过程中 ,多种因素可导致气道上皮损伤。损伤的气道上皮细胞通过细胞因子介质与气道平滑肌细胞、成纤维细胞及炎症细胞间的相互作用 ,参与了气道炎症、气道重塑及气道高反应性的形成 ,成为哮喘发病过程的中心环节     

循环纤维细胞与支气管哮喘

支气管哮喘（简称哮喘）气道重塑是慢性哮喘不可逆性气流受限的重要原因,是由多种细胞共同作用最终导致气道结构异常的过程,目前机制尚未完全明确。近年来,越来越多的研究结果表明,循环纤维细胞在哮喘的气道重塑中发挥着重要作用。本文就循环纤维细胞的基本生物学特性以及其参与哮喘气道重塑的研究现状及进展作一综述。     

IL-22对人气道细胞的作用

目的 探讨IL-22对人气道上皮细胞、气道平滑肌细胞、气道成纤维细胞的生理学作用.方法 用实时定量PCR 检测气道上皮细胞、气道平滑肌细胞、气道成纤维细胞哮喘血清刺激前后IL-22R1 mRNA表达的变化.不同浓度的IL-22(10 ng/ml,100 ng/ml,1 000 ng/ml)刺激气道上皮细胞、气道平滑肌细胞和气道成纤维细胞后,用MTT法检测细胞的增殖,用流式细胞技术(FACS)检测细胞的凋亡和坏死.结果 哮喘血清刺激后气道上皮细胞IL-22R1 mRNA表达降至正常对照组的9%,气道平滑肌细胞IL-22R1 mRNA表达升高至正常对照组的345倍,而气道成纤维细胞IL-22R1 mRNA表达无明显变化.高剂量(1 000 ng/ml)的IL-22刺激气道上皮细胞和气道成纤维细胞12、24 h可显著降低细胞增殖(P<0.05,P<0.01).三种不同浓度的IL-22刺激气道上皮细胞24 h后均导致细胞凋亡显著下降(P<0.05),低浓度的IL-22(10 ng/ml)导致细胞坏死增加(P<0.01).不同浓度的IL-22刺激气道平滑肌细胞后,细胞凋亡和坏死无显著性变化.中、高浓度IL-22(100 ng/ml,1 000 ng/ml)刺激气道成纤维细胞后,细胞坏死率显著下降(P<0.05).结论 IL-22在支气管哮喘中对气道上皮的作用具有双重性,并与支气管哮喘的病程相关;而对气道平滑肌细胞的作用则可能与浓度及病程相关.支气管哮喘后续阶段,IL-22对气道成纤维细胞作用轻微.     

碱性成纤维细胞生长因子与支气管哮喘

碱性成纤维细胞生长因子(basic fibroblast growth factor,b-FGF)是一种肝素黏合多肽,具有促进细胞增殖、分化和黏附作用等多种细胞生物学活性.近年来研究表明b-FGF与支气管哮喘(简称哮喘)气道重塑的关系密切.目前,哮喘的发病机制仍不是很清楚,治疗方法也在探索中,b-FGF的研究有可能为研究哮喘发病机制及治疗提供新的亮点.     

中药对支气管哮喘气道重塑干预机制研究进展

正支气管哮喘(简称哮喘)是最常见的慢性呼吸系统疾病之一,以持续性慢性气道炎症、气道高反应性、气道重塑为主要特点。气道重塑是哮喘的重要特征之一,它是指气道炎症、组织损伤及随后不正常修复导致气道壁结构的改变~([1])。气道重塑的病理改变主要有:气道上皮细胞的改变、炎性细胞浸润、杯状细胞增生、气道平滑肌细胞(ASMC)增殖与迁移、成纤维细胞数量增多、细胞外基质(ECM)沉积、气道     

Rho/ROCK信号转导通路与支气管哮喘气道重塑

支气管哮喘(简称哮喘)是多种细胞及其组分参与的慢性非特异性炎症性疾病,气道反复炎症损伤与修复造成的气道重塑是哮喘主要的病理生理学特征,预防气道重塑是哮喘干预治疗的重要潜在靶点,是改善哮喘预后的重要手段.Rho通过激活下游效应物Rho相关卷曲螺旋形成蛋白激酶(Rho associated coiled coil fotruing protein kinase,ROCK)作用于气道平滑肌细胞及调节细胞因子和炎性因子等的产生,在哮喘气道重塑的形成与发展中起关键的作用,ROCK抑制剂能有效抑制哮喘动物模型的气道炎症和气道重塑作用.     

Airway remodeling in asthma and irreversible airflow limitation-ECM deposition in airway and possible therapy for remodeling-.

Airway remodeling in asthma is characterized by goblet cell hyperplasia, subepithelial fibrosis, and hyperplasia and hypertrophy of airway smooth muscle cells. The airway wall thickness increases because of subepithelial fibrosis, and hyperplasia and hypertrophy of the airway smooth muscle cells and submucosal glands. Airway remodeling, therefore, can often cause irreversible airflow limitation and an increase of airway hyperresponsiveness. Recent studies have described the molecular and cellular mechanisms of collagen deposition in the airway wall such as subepithelial fibrosis. Fibroblasts or myofibroblasts play a critical role in the exaggerated deposition of collagen in asthmatic airways. Bone marrow derived fibroblasts may play a role in fibrotic remodeling in asthmatic airways. Airway remodeling is induced by cytokines and mediators produced in chronic allergic airway inflammation. Since, once formed, remodeling is resistant to asthma therapy, early intervention with inhaled corticosteroid should be considered to prevent the progress of airway remodeling.     

Vascular Endothelial Growth Factor as a Key Inducer of Angiogenesis in the Asthmatic Airways

Asthma is a chronic inflammatory disease of the airways characterized by structural airway changes, which are known as airway remodeling, including smooth muscle hypertrophy, goblet cell hyperplasia, subepithelial fibrosis, and angiogenesis. Vascular remodeling in asthmatic lungs results from increased angiogenesis, which is mainly mediated by vascular endothelial growth factor (VEGF). VEGF is a key regulator of blood vessel growth in the airways of asthma patients by promoting proliferation and differentiation of endothelial cells and inducing vascular leakage and permeability. In addition, VEGF induces allergic inflammation, enhances allergic sensitization, and has a role in Th2 type inflammatory responses. Specific inhibitors of VEGF and blockers of its receptors might be useful to control chronic airway inflammation and vascular remodeling, and might be a new therapeutic approach for chronic inflammatory airway disease like asthma.     

Thrombin in the Airways of Asthmatic Patients

The mechanism of airway remodeling in asthmatic patients is poorly understood. Thrombin is a multifunctional protease that, in addition to its critical role in thrombotic processes, has also been described as inducing cellular and molecular events relevant to tissue remodeling. The present investigation was undertaken to evaluate the activity of thrombin in the sputum of asthmatic patients and its potential role in airway remodeling. The study population comprised 8 healthy subjects and 14 stable patients with bronchial asthma. The concentrations of thrombin, thrombin-antithrombin complex (TAT), and tissue factor were measured in the sputum of all subjects. The concentrations of thrombin (p= 0.007), TAT (p= 0.01), and tissue factor (p= 0.02) in sputum were significantly higher in asthmatic patients than in healthy controls. The proliferative effects that sputum from asthmatic patients (p= 0.01) and thrombin (p= 0.03) have on cultured human smooth muscle cells was inhibited significantly in the presence of recombinant hirudin, a specific thrombin inhibitor. Significant statistical correlation was observed between the degree of bronchial responsiveness and the sputum concentrations of thrombin (r=−0.8; p= 0.02) and TAT (r=−0.9; p= 0.01). The results of this study showed that increased thrombin generation occurs in the airway of patients with asthma and that it may play a role in the pathogenesis of airway remodeling. Further studies should be carried out to assess whether these findings are also observed in other airway diseases. Accepted for publication: 6 April 1999     

Inflammation and remodeling of the distal airways: studies in humans and experimental models

Asthma is characterized by inflammation and remodeling of the airways, giving rise to airway obstruction and symptoms of wheezing, chest tightness, cough and dyspnea. Most of these observations arise from the study of samples obtained from the central airways by distinct methods. However, it is currently accepted that this inflammatory process occurs not only in the central airway but also in the small airway and even in the pulmonary parenchyma of all asthmatic patients, even those with mild asthma. CD4+ lymphocytes, activated eosinophils and IL-5 mRNA expression are present in a greater quantity in the small airways. Also present is remodeling, with an increase in submucosal thickness, the muscular layer and adventitia. This inflammatory process causes a disconnection between the pulmonary parenchyma and the airway, giving rise to obstruction of the small airway, which is currently considered to be predominant in asthmatic patients. Likewise, studies of experimental asthma in animals support the substantial role of the distal airway. Recognition that asthma affects the entire airway could be clinically important and lead to the distal lung being considered as a target in any effective therapeutic strategy. However, longitudinal studies are required to evaluate the impact of distal airway inflammation and its treatment in asthma.     

Asthma concepts in the new millennium: update in asthma pathophysiology.

This article reviewed current concepts of airway inflammation with a special emphasis on the epithelium, smooth muscle dysfunction, and airway remodeling. An alternative therapy on the importance of the airway microenvironment or epithelial mesenchymal trophic unit, myofibroblast activation, and role of growth factors was addressed. Future therapeutic strategies may involve these targets and a synergistic approach in preventing remodeling in selected asthmatic patients.     

Airway epithelial cell release of cytokines: modulation by various therapeutic agents.

The airway epithelial cell plays a central role in asthma pathogenesis and potential remodeling in secreting numerous cytokines, growth factors, chemokines, and nitric oxide. The role of various therapeutic agents on in vivo and in vitro antigen, growth factor, and respiratory syncytial virus-stimulated human small airway bronchial and alveolar epithelial cells will be reviewed. The experimental studies presented here, which used human airway epithelial cell cultures, may identify new therapeutic options in preventing amplified airway inflammation and remodeling in a subset of asthmatic or bronchiolitis patients with an atopic pre-disposition.     

地塞米松对哮喘大鼠气道重建、肥大细胞及IL-10的影响

目的观察地塞米松对哮喘大鼠模型气道重建和肺组织肥大细胞、IL-10的影响,探讨地塞米松在气道炎症和气道重塑中的作用机制,为临床治疗提供依据。方法采用卵白蛋白（OVA）腹腔注射致敏和雾化吸入激发建立哮喘大鼠模型,30只SD大鼠随机分为3组,正常对照组（A）、哮喘组（B）、地塞米松干预组（C）,每组10只。对肺组织切片行苏木精-伊红（HE）染色观察气道重塑情况。采用免疫组化和图像分析技术测定各组大鼠肺组织肥大细胞、IL-10的表达。结果哮喘组动物出现管壁增厚、平滑肌增生、黏液分泌增加等气道重塑的特征性改变,免疫组化染色显示气道各层细胞及炎性细胞均有IL-10表达减少。地塞米松干预组与哮喘组比较,炎症反应轻微,平滑肌增生、黏液分泌不明显,免疫组化染色显示各类细胞IL-10表达增高,与对照组比较差异有统计学意义。结论长期吸入变应原可导致气道重塑,肥大细胞、IL-10在气道重塑中发挥重要作用,地塞米松可通过抑制肥大细胞脱颗粒、增加IL-10表达发挥抑制炎症作用,进而缓解哮喘大鼠气道重塑的发生。     

白三烯受体拮抗剂对致敏大鼠血管内皮生长因子及其受体表达的影响

目的 研究白三烯受体拮抗剂(孟鲁司特)对支气管哮喘(简称哮喘)气道炎症和气道重塑的影响,揭示白三烯受体拮抗剂对血管内皮生长因子(VEGF)及其受体的调控作用.方法 将24只清洁级雄性SD大鼠按随机数字表法分为对照组、哮喘组和干预组,每组8只.对照组采用生理盐水致敏和激发,哮喘组采用卵清白蛋白致敏和激发,干预组在采用卵清白蛋白致敏和激发前给予孟鲁司特灌胃.采用肺功能检测各组大鼠气道呼气阻力;采用酶联免疫吸附法(ELISA)对各组大鼠血清中VEGF和白三烯D<4>(LTD4)进行定量分析;用免疫组织化学方法检测VEGF、VEGF受体1(VEGFR1)及VEGFR:在大鼠肺组织内的表达水平.采用图像分析软件测定肺组织切片中的血管计数、血管平滑肌厚度.结果 (1)肺功能检测显示哮喘组平均呼气阻力显著升高;(2)对照组血清中VEGF和LTD4的水平分别为(17±5)ng/L和(6.1±0.7)ng/L,哮喘组分别为(31±6)ng/L和(10.7±3.5)ng/L,干预组分别为(15±4)ng/L和(9.8±1.6)ng/L,对照组和干预组分别与哮喘组比较差异有统计学意义(F值分别为63.78和39.56,均P<0.01);(3)免疫组织化学结果显示哮喘组VEGF及受体均大量表达,而对照组和干预组有较少表达.(4)图像分析显示,对照组、哮喘组和干预组的血管计数分别为14±2、22±2和16±4.(5)直线相关分析显示,血管计数与血清中VEGF的水平正相关(r=0.705,P<0.05).结论 VEGF及其受体在哮喘气道及肺内过度表达,参与了气道炎症和气道血管重塑的过程.孟鲁司特可能通过影响VEGF及其受体的表达影响气道炎症和气道血管重塑的病理生理过程.     

Fas/FasL与支气管哮喘

Fas受体和Fas配体(FasL)在免疫细胞上的表达相对较高,其介导的细胞凋亡、增殖与免疫细胞的凋亡、增殖及功能发挥密切相关,在哮喘免疫耐受及调控异常、Th1/Th2失衡、气道炎症、黏液产生、气道高反应及气道重塑中发挥了重要作用,有望成为哮喘治疗的突破口。但是,在Fas/FasL信号转导过程中,各种因素构成了一个复杂的调控网络,深入研究Fas/FasL信号转导途径及其相关的调控机制才能为哮喘治疗开创新途径。