Rho激酶与哮喘气道高反应性

炎症细胞和结构细胞促进哮喘患者支气管的急性收缩和慢性气道重建。当前哮喘的治疗不能有效地抑制气道高反应性和气道重建。近来发现Rho激酶在哮喘的发病中起重要作用，而Rho激酶抑制剂可抑制气道平滑肌收缩、调节气道平滑肌特异性的基因转录、减轻气道壁增厚和气道炎症，从而减轻急性和慢性气道高反应性。     

Clinical assessment of airway remodeling in asthma

Airway remodeling is an established feature of asthma. Histologic examination is essential in the assessment of remodeling that is a pathologic concept. Examinations of autopsied or resected lung have enabled detailed morphologic and morphometric studies and have provided fundamental knowledge of airway remodeling in asthma. However, such materials are only accidentally available, and clinical information may often be insufficient in autopsied cases. Bronchoscopic mucosal biopsy has been widely used since the 1980s, and has contributed substantially to basic investigations of inflammation and remodeling. However such specimens are limited in size and depth, limited to central airways, and the procedure might be too invasive to be repeated. Remodeling can also be assessed indirectly. Pulmonary function tests to evaluate chronic airflow obstruction are available in clinical settings and suitable for screening or mass studies, but they may be affected by concomitant diseases or short-term asthma control. Computed tomography (CT) has recently been utilized to assess remodeling. It cannot discern pathologic details but provides a broader range of airway/lung morphology and may be less invasive compared to biopsy. In addition to classic subjective evaluations, quantitative assessment has been reported for central airway dimensions, such as airway wall area, luminal area and wall thickness, and for peripheral airway abnormality or air trapping as measured by decreased lung attenuation or increased mosaic perfusion. This article summarizes the merits and limitations of various methods to assess airway remodeling, and describes the details of methodologies, interpretations, pathophysiologic relevance, and future directions of asthmatic airway remodeling assessed by CT.     

Tissue remodeling as a feature of persistent asthma

A chronic inflammatory process is almost invariably associated with tissue damage and healing. Healing results in repair and replacement of dead or damaged cells by viable cells. Repair usually involves 2 distinct processes: regeneration, which is the replacement of injured tissue by parenchymal cells of the same type, and replacement by connective tissue and its eventual maturation into scar tissue. In many instances both processes contribute to the healing response. Chronic inflammatory disease can therefore lead to a wide variety of consequences, from complete or partial restitution of organ structure and function to fibrosis. Asthma is characterized by a chronic inflammatory process of the airways. The ensuing healing process results in structural alterations referred to as a remodeling of the airways. The mechanisms underlying these structural alterations are still largely unknown. They are likely to be heterogeneous, leading—through the highly dynamic process of cell de-differentiation, migration, differentiation, and maturation—to changes in connective tissue deposition and to the altered restitution of airways structure, resulting in mucus gland hyperplasia, neovascularization, fibrosis, and an increase in smooth muscle mass. (J Allergy Clin Immunol 2000;105:1041-53.)     

1,25-二羟维生素D_3减轻哮喘小鼠的气道重塑

目的探讨1,25-二羟维生素D3(1,25(OH)2D3,VD)对哮喘小鼠气道重塑及其肺组织中基质金属蛋白酶-9(MMP-9)表达的干预作用及其机制。方法建立慢性哮喘小鼠模型,将小鼠随机分为对照组、哮喘组、地塞米松(DEX)组及VD组。HE染色观察各组气道结构;用计算机图像分析系统评价各组气道重塑;用明胶酶谱法及RT-PCR法检测各组的MMP-9的活性及其mRNA表达。结果 (1)哮喘组出现炎性细胞浸润增多、上皮细胞脱落及平滑肌细胞层增厚等气道重塑改变,而DEX组及VD组均可部分逆转上述病理改变;(2)DEX组及VD组的支气管内壁厚度、平滑肌层厚度和平滑肌细胞核数显著低于哮喘组,但仍高于对照组(P<0.05);(3)DEX组及VD组肺组织MMP-9的活性分别为对照组的(2.24±0.16)倍及(3.46±0.09)倍,而哮喘组是对照组的(7.87±0.09)倍(P<0.05);(4)各组MMP-9mRNA相对定量分别为对照组(0.57±0.08)、哮喘组(5.74±0.13)、DEX组(2.63±0.11)及VD组(3.16±0.09),且两两比较均P<0.05。结论 1,25(OH)2D3可显著减轻哮喘气道...     

Differences in airway remodeling between asthma and chronic obstructive pulmonary disease

The functional consequence of asthma and chronic obstructive pulmonary disease (COPD) is airflow limitation, which is mostly reversible in asthma and not fully reversible in COPD. In both diseases, inflammatory conditions are associated with cellular and structural changes, referred to as remodeling, and these structural changes may lead to thickening of the airway wall, thereby promoting airway narrowing and airflow limitation. However, the pattern of infilatrated cells and the pattern of structural changes occur differently in the two diseases. In asthma, CD4+, T lymphocytes, eosinophils, and mast cells are the predominant cells involved, whereas COPD, CD8+, T lymphocytes, and macrophages are predominantly involved. In severe cases of asthma and COPD, neutrophil infiltration becomes evident. Regarding structural changes, epithelial injury and early thickening of reticular basement membrane are highly characteristic of the airway wall of asthmatics. Increases in airway smooth muscle mass occur in large airways of severe asthmatics and in small airways of patients with COPD. Thickening of the airway wall, golblet cell hyperplasia, mucous gland hypertrophy, and the luminal obstruction caused by inflammatory exudates and mucous are features of both asthma and COPD. Squamous epithelial metaplasia and airway wall fibrosis are commonly observed characteristics of COPD. Destruction and fibrosis of the alveolar wall occur in COPD but not in asthma. The remodeling processes accompanied by chronic inflammatory infiltrates interact in a complex fashion and contribute to the development of airflow limitation in both asthma and COPD.     

1,25-二羟维生素D3对哮喘小鼠气道重塑的干预作用

 目的 探讨1,25-二羟维生素D3(1,25-(OH)2D3,VD)对哮喘小鼠气道重塑及其肺组织中基质金属蛋白酶-9(MMP-9)表达的干预作用及其机制。方法 卵蛋白致敏和激发建立慢性哮喘小鼠模型,BALB / c 小鼠随机分为对照组、哮喘组、地塞米松(DEX）组及VD组。HE 染色观察各组气道结构改变情况;采用计算机图像分析系统评价各组气道重塑情况;采用明胶酶谱法及RT-PCR法检测各组的MMP-9的活性及其mRNA表达水平。结果 ①HE 染色提示哮喘组与对照组相比出现炎性细胞浸润增多、上皮细胞脱落及平滑肌细胞层增厚等气道重塑改变,而DEX组及VD组均可部分逆转上述病理改变;②DEX组及VD组的支气管内壁厚度、平滑肌层厚度和平滑肌细胞核数显著低于哮喘组,但仍高于对照组( P < 0.05);③DEX组及VD组肺组织MMP-9的活性及其mRNA表达水平均明显低于哮喘组,但仍高于对照组 ( P < 0.05) 。结论 VD可显著减轻哮喘气道重塑的病理改变;并可通过部分抑制肺内 MMP-9的表达来延缓气道重塑进程。     

外源性H2S干预对O3致哮喘小鼠气道反应性和气道重塑的影响

 目的: 探讨外源性硫化氢(hydrogen sulfide,H₂S)对臭氧(ozone,O₃)致哮喘小鼠气道反应性和气道重塑的影响。方法: 将15只SPF级C57BL/6雌性小鼠随机分为对照组、O₃组和NaHS+O₃组,每组5只。O₃处理前0.5 h,对照组和O₃组腹腔注射生理盐水,NaHS+O₃组腹腔注射NaHS(H₂S的供体);O₃组和NaHS+O₃组隔天用O₃处理,对照组则呼吸清洁空气。持续4周后无创测定小鼠的气道反应性,随后进行气管环张力测定,通过肺组织HE染色测定支气管基底膜周径(Pbm)和管壁总面积(Wat)并标准化衡量气道重塑程度,并行AB-PAS染色测定肺组织中杯状上皮细胞的变化情况以进一步评价气道重塑程度。结果: 与对照组相比,O₃组小鼠的气道反应性显著增高;NaHS+O₃组明显低于O₃组,但与对照组相比差异无统计学显著性。与对照组相比,O₃组小鼠在乙酰甲胆碱刺激时的气管收缩力显著加大;NaHS+O₃组明显小于O₃组。与对照组相比,O₃组小鼠的支气管壁厚度明显加大;NaHS+O₃组显著小于O₃组但仍大于对照组。与对照组相比,O₃组小鼠肺组织中杯状上皮细胞占气道上皮细胞总面积的百分比显著上升;NaHS+O₃组显著低于O₃组但仍高于对照组。结论: 外源性H₂S对O₃所致哮喘的气道高反应性和气道重塑有缓解与保护作用,有望为临床药物治疗哮喘提供新靶点。     

Glutamine preferentially inhibits T-helper type 2 cell-mediated airway inflammation and late airway hyperresponsiveness through the inhibition of cytosolic phospholipase A2 activity in a murine asthma model

Background The non‐essential amino acid, l ‐glutamine (Gln), is abundant in the human body. Gln exhibits beneficial effects on endotoxic shock through the inhibition of cytosolic phospholipase A₂ (cPLA₂) activity. cPLA₂ has been reported to be implicated in the pathogenesis of asthma, but the effects of Gln on asthma have not yet been defined. Objective To investigate the effects of Gln on allergic bronchial inflammation and airway hyperresponsiveness (AHR), and to determine the possible action mechanisms of Gln in a murine model of asthma. Methods cPLA₂ phosphorylation was assessed by immunoprecipitation and Western blotting. Smears of bronchoalveolar lavage cells were stained with Diff‐Quik solution for differential cell counting. Airway levels of the proteins [T‐helper type‐1 (Th1) and Th2 cytokines, and mucin] were measured by ELISA. mRNA expression of cytokines was assessed by real‐time RT‐PCR. AHR was assessed as a change in airway resistance (RL). Histological studies were performed to assess the levels of mucin and pulmonary inflammation. Results Systemic Gln administration inhibited cPLA₂ phosphorylation and its enzymatic activity in the lungs. Additionally, Gln effectively suppressed the key features of Th2‐dependent asthmatic features, such as airway eosinophilia, mucus formation, and airway type 2 cytokine production, as well as late AHR. Conclusion Gln was found to be effective in the suppression of Th2‐dependent phenotypes and late AHR, and this effect of Gln appeared to be at least partially attributable to its ability to suppress cLPA₂ activity in the airway. Our results suggest that clinical use of Gln for patients with asthma may be beneficial.     

气道上皮IL-25促进哮喘气道重塑

目的:通过检测白细胞介素-25(IL-25)在嗜酸细胞性哮喘(EA)及非嗜酸细胞性哮喘(NEA)患者的血清、诱导痰及气道上皮中的表达,探讨其在支气管哮喘气道重塑中的作用。方法:选取初诊的哮喘患者55例,健康对照组27例,所有受试者均进行肺通气功能检查,然后采集空腹静脉血及诱导痰。据诱导痰中嗜酸性粒细胞(EOS)的比例将哮喘患者分为EA组和NEA组。采用ELISA检测血清及诱导痰中IL-25的水平,同时对其中的10例EA组患者、10例NEA组患者及10例健康对照者行电子支气管镜气道黏膜活检,免疫组织化学技术分析IL-25在气道上皮的表达,HE染色测量气道重塑的重要指标-基底膜厚度,并行血清及诱导痰中IL-25的水平与基底膜平均厚度的相关性分析。结果:与正常对照组相比,EA和NEA组哮喘患者的肺功能轻度受损。ELISA结果显示哮喘患者血清及诱导痰中IL-25的水平明显高于对照组(P<0.05),而EA和NEA组哮喘患者间差异无统计学意义(P>0.05)。免疫组织化学结果显示哮喘患者气道上皮IL-25的表达明显高于对照组,HE染色显示气道黏膜下的基底膜厚度明显增加(P<0.05)。相关性分析显示哮喘患者血清及诱导痰中IL-25水平与气道黏膜下基底膜平均厚度成正相关。结论:IL-25可能有促进哮喘气道重塑的作用,嗜酸性粒细胞与基底膜厚度无明显相关性,其在哮喘气道重塑中的作用可能是有限的。     

The effects of nodakenin on airway inflammation,hyper-responsiveness and remodeling in a murine model of allergic asthma

Context: Nodakenin is a major coumarin glucoside in the root of Peucedanum decursivum Maxim, a commonly used traditional Chinese medicine for the treatment of asthma and chronic bronchitis for thousands of years.

Objective: In this work, the anti-asthma potential of nodakenin was studied by investigation of its effect to suppress airway inflammation, hyper-responsiveness and remodeling in a murine model of chronic asthma.

Materials and methods: BALB/c mice sensitized to ovalbumin (OVA) were challenged with aerosolized OVA for 8 weeks, orally administered with nodakenin at doses of 5, 10 and 20?mg/kg before each OVA challenge.

Results: Compared with the model group, nodakenin treatment markedly inhibited airway inflammation, hyper-responsiveness and remodeling, showing improvement in subepithelial fibrosis, smooth muscle hypertrophy, and goblet cell hyperplasia, and decreased levels of interleukin (IL)-4, IL-5, IL-13 and matrix metalloproteinase-2/-9 in bronchoalveolar lavage fluid, and the level of OVA-specific IgE in serum. In addition, the NF-κB DNA-binding activity in lung tissues was also reduced by nodakenin treatment.

Conclusions: These data indicated that nodakenin might mitigate the development of chronic experimental allergic asthma.     

Mechanisms of inflammation-mediated airway smooth muscle plasticity and airways remodeling in asthma

Recent evidence points to progressive structural change in the airway wall, driven by chronic local inflammation, as a fundamental component for development of irreversible airway hyperresponsiveness. Acute and chronic inflammation is orchestrated by cytokines from recruited inflammatory cells, airway myofibroblasts and myocytes. Airway myocytes exhibit functional plasticity in their capacity for contraction, proliferation, and synthesis of matrix protein and cytokines. This confers a principal role in driving different components of the airway remodeling process, and mediating constrictor hyperresponsiveness. Functional plasticity of airway smooth muscle (ASM) is regulated by an array of environmental cues, including cytokines, which mediate their effects through receptors and a number of intracellular signaling pathways. Despite numerous studies of the cellular effects of cytokines on cultured airway myocytes, few have identified how intracellular signaling pathways modulate or induce these cellular responses. This review summarizes current understanding of these concepts and presents a model for the effects of inflammatory mediators on functional plasticity of ASM in asthma.     

Methacholine vs adenosine on intra and extrathoracic airway hyperresponsiveness in patients with cough variant asthma

Background: Airway hyperresponsiveness (AHR) can be studied by bronchoprovocation test (BPT) using direct (methacholine – MCh) or indirect (adenosine 5′‐monophosphate – AMP) stimuli. These two substances have not been compared in cough variant asthma (CVA). Objective: We designed a randomized, single‐blind, cross‐over study to compare AMP and MCh in the detection of CVA. Additionally, we examined whether assessment of extrathoracic airway hyperresponsiveness (EAHR) during MCh and AMP helped in the evaluation of CVA. Methods: Patients with CVA with previous positive MCh BPT performed challenges with AMP and MCh. The variables were: (i) a provocative dose producing a 20% fall in forced expiratory volume in 1 s (FEV₁) value (PD₂₀MCh); (ii) a provocative dose producing a 25% fall in the maximal mid‐inspiratory flow (FIF₅₀) from baseline (PD₂₅MCh) for MCh; (iii) a provocative concentration producing a 20% fall in FEV₁ value (PC₂₀AMP) and (iv) a provocative concentration producing a 25% fall in the FIF₅₀ from baseline (PC₂₅AMP) for AMP. Results: All 113 patients with CVA responded to PD₂₀MCh and 96% and 69% responded to PC₂₀AMP, if we used PC₂₀ ≤ 200 mg/ml or PC₂₀ ≤ 100 mg/ml, respectively, with an excellent correlation between these two tests (r = 0.87 and 0.76, respectively). Extrathoracic AHR associated with AHR was found in 10% in MCh challenge and in 11% with AMP challenge and no patients had EAHR alone. Conclusion: Adenosine challenges correlate well with MCh in patients with CVA. A minority (c. 10%) of CVA patients have EAHR as measured by these tests, while most had AHR as assessed with each of the challenge agents.     

HMGB1 contributes to allergen-induced airway remodeling in a murine model of chronic asthma by modulating airway inflammation and activating lung fibroblasts

The pro-inflammation factor high-mobility group box protein 1 (HMGB1) has been implicated in the pathogenesis of asthma. In this study, we used a murine model of chronic asthma to evaluate the effects of HMGB1 on airway remodeling. Female BALB/c mice were randomly divided into four groups: control, ovalbumin (OVA) asthmatic, OVA+isotype antibody and OVA+anti-HMGB1 antibody. Anti-HMGB1 antibody therapy was started on day 21 and was administered three times per week for 6 weeks before intranasal challenge with OVA. In this mouse model, HMGB1 expression is significantly elevated. The anti-HMGB1 antibody group exhibited decreased levels of immunoglobulin E (IgE) and inflammatory mediators and reduced inflammatory cell accumulation, airway hyperresponsiveness (AHR), mucus synthesis, smooth muscle thickness and lung collagen content compared with the OVA groups. Treatment with HMGB1 increased proliferation, migration, collagen secretion and α-smooth muscle actin (SMA) expression in MRC-5 cells. Treatment with the HMGB1/IL-1β complex significantly increased the expression and secretion of transforming growth factor (TGF-β1), matrix metalloproteinase (MMP)-9 and vascular endothelial growth factor (VEGF). Altogether, these results suggest that blocking HMGB1 activity may reverse airway remodeling by suppressing airway inflammation and modulating lung fibroblast phenotype and activation.     

KyoT2 结合蛋白KBP1对RBP-J介导的转录活性的影响

目的 :研究KyoT2与KyoT2结合蛋白 1(KyoT2 bindingprotein1,KBP1)之间的物理相互作用 ,以及这种相互作用对重组信号结合蛋白J (recombinationsignalbindingprotein Jκ ,RBP J)介导的转录活性的影响。方法 :体外GST pulldown、体内免疫共沉淀、哺乳动物细胞双杂交实验和报告基因实验证实 ,KBP1与KyoT2之间存在物理和功能上的相互作用。结果 :体内和体外证实 ,KBP1与KyoT2之间均存在相互作用。转录活性分析实验显示 ,过表达KBP1可拮抗RING1对RBP J介导的转录的抑制效应。结论 :KBP1可通过与RING1竞争结合KyoT2而间接参与对Notch信号途径的调控