支气管哮喘患者血清miR-29a-3p、miR-98-5p表达水平与肺功能、气道炎症和糖皮质激素治疗敏感性的关系研究

摘要 目的：探讨支气管哮喘（BA）患者血清微小核糖核酸（miR）-29a-3p、miR-98-5p表达水平与肺功能、气道炎症和糖皮质激素（GC）治疗敏感性的关系。方法：选取2020年1月～2022年1月潍坊市人民医院收治的150例BA患者为BA组,根据BA患者GC治疗敏感性将其分为抵抗组43例和敏感组107例,另选取同期57名体检健康者为对照组。收集BA组、对照组肺功能和气道炎症指标资料,采用实时荧光定量逆转录聚合酶链式反应（qRT-PCR）检测两组血清miR-29a-3p、miR-98-5p表达水平。通过Spearman相关性分析BA患者血清miR-29a-3p、miR-98-5p表达水平与肺功能和气道炎症指标的相关性,单因素和多因素Logistic回归分析BA患者GC治疗抵抗的影响因素。结果：与对照组比较,BA组血清miR-29a-3p、miR-98-5p表达水平和第1秒用力呼气容积占预计值百分比（FEV₁％）、第1秒用力呼气容积/用力肺活量（FEV₁/FVC）、峰值呼气流速（PEF）降低,呼出气一氧化氮（FeNO）水平升高（P均＜0.05）。Spearman相关性分析显示,BA患者血清miR-29a-3p、miR-98-5p表达水平与FEV₁％、FEV₁/FVC、PEF呈正相关,与FeNO水平呈负相关（P均＜0.05）。单因素分析显示,抵抗组体质指数＞24 kg/m²、吸烟比例高于敏感组,血清miR-29a-3p、miR-98-5p表达水平低于敏感组（P＜0.05）。多因素Logistic回归分析显示,体质指数＞24 kg/m²、吸烟为BA患者GC治疗抵抗的独立危险因素,血清miR-29a-3p、miR-98-5p表达水平升高为其独立保护因素（P均＜0.05）。结论：BA患者血清miR-29a-3p、miR-98-5p水平降低,与肺功能下降、气道炎症和GC治疗抵抗有关。     

Bromelain exerts anti-inflammatory effects in an ovalbumin-induced murine model of allergic airway disease

OBJECTIVE: Bromelain, a clinically used pineapple extract and natural product, has reported anti-inflammatory and immunomodulatory activities. The purpose of this study was to determine the effect of bromelain treatment in an ovalbumin (OVA)-induced murine model of allergic airway disease (AAD). METHODS: To establish AAD, mice were sensitized with intraperitoneal (i.p.) OVA/alum and challenged with daily OVA aerosols. Mice were treated i.p. with either saline, 2 or 6 mg/kg bromelain, twice daily for four consecutive days. Bronchoalveolar lavage leukocytes and cytokines, lung histology, airway hyperresponsiveness, and lymphocyte populations via flow cytometry were compared between groups. RESULTS: Bromelain treatment of AAD mice resulted in reduced total BAL leukocytes, eosinophils, CD4+ and CD8+ T lymphocytes, CD4+/CD8+ T cell ratio, and IL-13. CONCLUSION: Bromelain attenuated development of AAD while altering CD4+ to CD8+ T lymphocyte populations. The reduction in AAD outcomes suggests that bromelain may have similar effects in the treatment of human asthma and hypersensitivity disorders.     

Abnormal ion content, hydration and granule expansion of the secretory granules from cystic fibrosis airway glandular cells

The absence or decreased expression of cystic fibrosis transmembrane conductance regulator (CFTR) induces increased Na(+) absorption and hyperabsorption of the airway surface liquid (ASL) resulting in a dehydrated and hyperviscous ASL. Although the implication of abnormal airway submucosal gland function has been suggested, the ion and water content in the Cystic Fibrosis (CF) glandular secretory granules, before exocytosis, is unknown. We analyzed, in non-CF and CF human airway glandular cell lines (MM-39 and KM4, respectively), the ion content in the secretory granules by electron probe X-ray microanalysis and the water content by quantitative dark field imaging on freeze-dried cryosections. We demonstrated that the ion content (Na(+), Mg(2+), P, S and Cl(-)) is significantly higher and the water content significantly lower in secretory granules from the CF cell line compared to the non-CF cell line. Using videomicroscopy, we observed that the secretory granule expansion was deficient in CF glandular cells. Transfection of CF cells with CFTR cDNA or inhibition of non-CF cells with CFTR(inh)-172, respectively restored or decreased the water content and granule expansion, in parallel with changes in ion content. We hypothesize that the decreased water and increased ion content in glandular secretory granules may contribute to the dehydration and increased viscosity of the ASL in CF.     

Thioredoxin suppresses airway hyperresponsiveness and airway inflammation in asthma

Thioredoxin (TRX) is a 12-kDa redox (reduction/oxidation)-active protein that has a highly conserved site (-Cys-Gly-Pro-Cys-) and scavenges reactive oxygen species. Here we examined whether exogenously administered TRX modulated airway hyperresponsiveness (AHR) and airway inflammation in a mouse asthma model. Increased AHR to inhaled acetylcholine and airway inflammation accompanied by eosinophilia were observed in OVA-sensitized mice. Administration of wild-type but not 32S/35S mutant TRX strongly suppressed AHR and airway inflammation, and upregulated expression of mRNA of several cytokines (e.g., IL-1alpha, IL-1beta, IL-1 receptor antagonist, and IL-18) in the lungs of OVA-sensitized mice. In contrast, TRX treatment at the time of OVA sensitization did not improve AHR or airway inflammation in OVA-sensitized mice. Thus, TRX inhibited the asthmatic response after sensitization, but did not prevent sensitization itself. TRX and redox-active protein may have clinical benefits in patients with asthma.     

Respiratory epithelial cells require Toll-like receptor 4 for induction of Human β-defensin 2 by Lipopolysaccharide

Background

The respiratory epithelium is a major portal of entry for pathogens and employs innate defense mechanisms to prevent colonization and infection. Induced expression of human β-defensin 2 (HBD2) represents a direct response by the epithelium to potential infection. Here we provide evidence for the critical role of Toll-like receptor 4 (TLR4) in lipopolysaccharide (LPS)-induced HBD2 expression by human A549 epithelial cells.

Methods

Using RTPCR, fluorescence microscopy, ELISA and luciferase reporter gene assays we quantified interleukin-8, TLR4 and HBD2 expression in unstimulated or agonist-treated A549 and/or HEK293 cells. We also assessed the effect of over expressing wild type and/or mutant TLR4, MyD88 and/or Mal transgenes on LPS-induced HBD2 expression in these cells.

Results

We demonstrate that A549 cells express TLR4 on their surface and respond directly to Pseudomonas LPS with increased HBD2 gene and protein expression. These effects are blocked by a TLR4 neutralizing antibody or functionally inactive TLR4, MyD88 and/or Mal transgenes. We further implicate TLR4 in LPS-induced HBD2 production by demonstrating HBD2 expression in LPS non-responsive HEK293 cells transfected with a TLR4 expression plasmid.

Conclusion

This data defines an additional role for TLR4 in the host defense in the lung.     

Mutation screening of the muscarinic m2 and m3 receptor genes in asthmatics,outgrow subjects,and normal controls

Muscarinic receptors are important in the development of airway hyperresponsiveness. In some patients with asthma and in animal models of hyperreactivity, functional abnormalities in these receptors are suggested to contribute to disease. Here, we have screened for single nucleotide polymorphisms in the coding region of human muscarinic m2 and m3 receptor genes using direct fluorescence sequencing. DNA samples from 102 current asthmatics and 58 who had outgrown asthma ("outgrow" patients) were compared with 70 random non-asthmatic controls. A mutation characterized by a single base substitution (A1050G, Ser350Ser) was identified in the muscarinic m2 receptor gene. This polymorphism was common and was represented in all three groups studied. In contrast, in the m3 receptor coding region examined, we found a very rare nucleotide variant (C261T, Ile87Ile), identified in only one of the 230 samples genotyped. Therefore, neither A1050G in the m2 receptor nor C261T in the m3 receptor is likely to be functionally significant for airway hyperresponsiveness in asthma. Our data suggest that both the m2 and m3 receptor genes are highly conserved, and no significant genetic mutations are related to their possible functional changes in human asthma.     

Protective effect of a Protein Epitope Mimetic CCR10 antagonist,POL7085, in a model of allergic eosinophilic airway inflammation

Background

Potential involvement of the CCR10/CCL28 axis was recently reported in murine models of allergic asthma. If confirmed, blockade of the CCR10 receptor would represent an alternative to current asthma therapies. We evaluated the effect of a novel Protein Epitope Mimetic CCR10 antagonist, POL7085, in a murine model of allergic eosinophilic airway inflammation.

Methods

Mice were sensitized and challenged to ovalbumin. POL7085, a CCR10 antagonist (7.5 and 15 mg/kg), dexamethasone (1 mg/kg) or vehicle were administered intranasally once daily 1h before each allergen challenge. On day 21, airway hyperresponsiveness, bronchoalveolar lavage inflammatory cells and Th2 cytokines, and lung tissue mucus and collagen were measured.

Results

Allergen challenge induced airway hyperresponsiveness in vehicle-treated animals as measured by whole body barometric plethysmography, and eosinophilia in bronchoalveolar lavage. POL7085 dose-dependently and significantly decreased airway hyperresponsiveness (34 ± 16 %) and eosinophil numbers in bronchoalveolar lavage (66 ± 6 %). In addition, the highest dose of POL7085 used significantly inhibited lung IL-4 (85 ± 4 %), IL-5 (87 ± 2 %) and IL-13 (190 ± 19 %) levels, and lung collagen (43 ± 11 %).

Conclusions

The Protein Epitope Mimetic CCR10 antagonist, POL7085, significantly and dose-dependently decreased allergen-induced airway hyperresponsiveness and airway inflammation after once daily local treatment. Our data give strong support for further investigations with CCR10 antagonists in asthmatic disease.

Electronic supplementary material

The online version of this article (doi:10.1186/s12931-015-0231-5) contains supplementary material, which is available to authorized users.     

Periostin: its role in asthma and its potential as a diagnostic or therapeutic target

Accumulating evidence shows that periostin, a matricellular protein, is involved in many fundamental biological processes such as cell proliferation, cell invasion, and angiogenesis. Changes in periostin expression are commonly detected in various cancers and pre-cancerous conditions, and periostin may be involved in regulating a diverse set of cancer cell activities that contribute to tumorigenesis, cancer progression, and metastasis. Periostin has also been shown to be involved in many aspects of allergic inflammation, such as eosinophil recruitment, airway remodeling, development of a Th2 phenotype, and increased expression of inflammatory mediators. In an in vivo model, bronchoalveolar lavage (BAL) fluid obtained from ovalbumin-challenged mice was found to contain significantly higher levels of periostin compared to BAL samples from control mice. To date, the molecular mechanisms involving periostin in relation to asthma in humans have not been fully elucidated. This review will focus on what is known about periostin and its role in the pathophysiological mechanisms that mediate asthma in order to evaluate the potential for periostin to serve as a biomarker and therapeutic target for the detection and treatment of asthma, respectively.     

Airways resistance and specific conductance for the diagnosis of obstructive airways diseases

Background

Airway resistance (R_AW) and specific airway conductance (sG_AW) are measures that reflect the patency of airways. Little is known of the variability of these measures between different lung diseases. This study investigated the contribution of R_AW and sG_AW to a diagnosis of obstructive airways disease and their role in differentiating asthma from COPD.

Methods

976 subjects admitted for the first time to a pulmonary practice in Belgium were included. Clinical diagnoses were based on complete pulmonary function tests and supported by investigations of physicians’ discretion. 651 subjects had a final diagnosis of obstructive diseases, 168 had another respiratory disease and 157 subjects had no respiratory disease (healthy controls).

Results

R_AW and sG_AW were significantly different (p < 0.0001) between obstructive and other groups. Abnormal R_AW and sG_AW were found in 39 % and 18 % of the population, respectively, in which 81 % and 90 % had diagnosed airway obstruction. Multiple regression revealed sG_AW to be a significant and independent predictor of an obstructive disorder. To differentiate asthma from COPD, R_AW was found to be more relevant and statistically significant. In asthma patients with normal FEV₁/FVC ratio, both R_AW and sG_AW were more specific than sensitive diagnostic tests in differentiating asthma from healthy subjects.

Conclusions

R_AW and sG_AW are significant factors that contribute to the diagnosis and differentiation of obstructive airways diseases.     

p38 MAPK通路在脂多糖致呼吸道上皮损伤中的作用

脂多糖(Lipopolysaccharide,LPS)是革兰阴性杆菌细胞壁的主要组成成分,也是一种很强的炎症反应和氧化应激诱导剂。呼吸道上皮是机体防御外界细菌、病毒、香烟烟雾等生物和化学因素损伤的天然屏障,在维持呼吸道局部微环境稳态中可发挥重要作用,也是吸入性药物治疗的主要靶细胞。呼吸道上皮结构完整性缺陷或功能紊乱还参与了哮喘、慢性阻塞性肺疾病等多种肺部疾病的发生和发展。LPS可引起呼吸道上皮损伤,但其具体的分子机制目前尚不清楚。p38丝裂原活化蛋白激酶(P38mitogen-activated protein kinase,p38 MAPK)作为MAPK家族四个亚家族成员之一,包含四个成员:p38α、p38β、p38γ和p38δ,可通过经典和非经典的p38 MAPK信号通路激活方式及通过激酶活性无关的功能参与调控炎症反应、细胞生长、细胞分化和细胞死亡等多种病理生理过程。本文就p38 MAPK信号通路在LPS致呼吸道上皮损伤中的作用做一综述。