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Jaramillo AM, Vladar EK, Holguin F, Dickey BF, Evans CM. Emerging cell and molecular targets for treating mucus hypersecretion in asthma. Allergol Int 2024; 73:375-381. [PMID: 38692992 DOI: 10.1016/j.alit.2024.04.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2024] [Accepted: 04/03/2024] [Indexed: 05/03/2024] Open
Abstract
Mucus provides a protective barrier that is crucial for host defense in the lungs. However, excessive or abnormal mucus can have pathophysiological consequences in many pulmonary diseases, including asthma. Patients with asthma are treated with agents that relax airway smooth muscle and reduce airway inflammation, but responses are often inadequate. In part, this is due to the inability of existing therapeutic agents to directly target mucus. Accordingly, there is a critical need to better understand how mucus hypersecretion and airway plugging are affected by the epithelial cells that synthesize, secrete, and transport mucus components. This review highlights recent advances in the biology of mucin glycoproteins with a specific focus on MUC5AC and MUC5B, the chief macromolecular components of airway mucus. An improved mechanistic understanding of key steps in mucin production and secretion will help reveal novel potential therapeutic strategies.
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Affiliation(s)
- Ana M Jaramillo
- Division of Pulmonary Sciences and Critical Care Medicine, University of Colorado School of Medicine, Aurora, CO, USA
| | - Eszter K Vladar
- Division of Pulmonary Sciences and Critical Care Medicine, University of Colorado School of Medicine, Aurora, CO, USA
| | - Fernando Holguin
- Division of Pulmonary Sciences and Critical Care Medicine, University of Colorado School of Medicine, Aurora, CO, USA
| | - Burton F Dickey
- Department of Pulmonary Medicine, Anderson Cancer Center, University of Texas M.D., Houston, TX, USA
| | - Christopher M Evans
- Division of Pulmonary Sciences and Critical Care Medicine, University of Colorado School of Medicine, Aurora, CO, USA.
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2
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Gutiérrez-Vera C, García-Betancourt R, Palacios PA, Müller M, Montero DA, Verdugo C, Ortiz F, Simon F, Kalergis AM, González PA, Saavedra-Avila NA, Porcelli SA, Carreño LJ. Natural killer T cells in allergic asthma: implications for the development of novel immunotherapeutical strategies. Front Immunol 2024; 15:1364774. [PMID: 38629075 PMCID: PMC11018981 DOI: 10.3389/fimmu.2024.1364774] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2024] [Accepted: 03/06/2024] [Indexed: 04/19/2024] Open
Abstract
Allergic asthma has emerged as a prevalent allergic disease worldwide, affecting most prominently both young individuals and lower-income populations in developing and developed countries. To devise effective and curative immunotherapy, it is crucial to comprehend the intricate nature of this condition, characterized by an immune response imbalance that favors a proinflammatory profile orchestrated by diverse subsets of immune cells. Although the involvement of Natural Killer T (NKT) cells in asthma pathology is frequently implied, their specific contributions to disease onset and progression remain incompletely understood. Given their remarkable ability to modulate the immune response through the rapid secretion of various cytokines, NKT cells represent a promising target for the development of effective immunotherapy against allergic asthma. This review provides a comprehensive summary of the current understanding of NKT cells in the context of allergic asthma, along with novel therapeutic approaches that leverage the functional response of these cells.
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Affiliation(s)
- Cristián Gutiérrez-Vera
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile
- Programa de Inmunología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
- Departamento de Tecnología Médica, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Richard García-Betancourt
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile
- Programa de Inmunología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Pablo A. Palacios
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile
- Programa de Inmunología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Marioly Müller
- Departamento de Tecnología Médica, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - David A. Montero
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile
- Programa de Inmunología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Carlos Verdugo
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile
- Programa de Inmunología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Francisca Ortiz
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile
- Programa de Inmunología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Felipe Simon
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile
- Facultad de Ciencias de la Vida, Universidad Andrés Bello, Santiago, Chile
| | - Alexis M. Kalergis
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile
- Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Pablo A. González
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile
- Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Noemi A. Saavedra-Avila
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY, United States
| | - Steven A. Porcelli
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY, United States
| | - Leandro J. Carreño
- Millennium Institute on Immunology and Immunotherapy, Santiago, Chile
- Programa de Inmunología, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
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3
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Kaminsky DA, Cockcroft DW, Davis BE. Respiratory System Dynamics. Semin Respir Crit Care Med 2023; 44:526-537. [PMID: 37429331 DOI: 10.1055/s-0043-1770058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/12/2023]
Abstract
While static mechanical forces govern resting lung volumes, dynamic forces determine tidal breathing, airflow, and changes in airflow and lung volume during normal and abnormal breathing. This section will examine the mechanisms, measurement methodology, and interpretation of the dynamic changes in airflow and lung volume that occur in health and disease. We will first examine how the total work of breathing can be described by the parameters of the equation of motion, which determine the pressure required to move air into and out of the lung. This will include a detailed description of airflow characteristics and airway resistance. Next, we will review the changes in pressure and flow that determine maximal forced inspiration and expiration, which result in the maximal flow-volume loop and the clinically important forced expired volume in 1 second. We will also assess the mechanisms and interpretation of bronchodilator responsiveness, dynamic hyperinflation, and airways hyperresponsiveness.
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Affiliation(s)
- David A Kaminsky
- Division of Pulmonary and Critical Care, Department of Medicine, University of Vermont Larner College of Medicine, Burlington, Vermont
| | - Donald W Cockcroft
- Division of Respirology, Critical Care and Sleep Medicine, University of Saskatchewan College of Medicine, Saskatoon Saskatchewan, Canada
| | - Beth E Davis
- Division of Respirology, Critical Care and Sleep Medicine, University of Saskatchewan College of Medicine, Saskatoon Saskatchewan, Canada
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4
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Farré R, Navajas D. Ventilation Mechanics. Semin Respir Crit Care Med 2023; 44:511-525. [PMID: 37467769 DOI: 10.1055/s-0043-1770340] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/21/2023]
Abstract
A fundamental task of the respiratory system is to operate as a mechanical gas pump ensuring that fresh air gets in close contact with the blood circulating through the lung capillaries to achieve O2 and CO2 exchange. To ventilate the lungs, the respiratory muscles provide the pressure required to overcome the viscoelastic mechanical load of the respiratory system. From a mechanical viewpoint, the most relevant respiratory system properties are the resistance of the airways (R aw), and the compliance of the lung tissue (C L) and chest wall (C CW). Both airflow and lung volume changes in spontaneous breathing and mechanical ventilation are determined by applying the fundamental mechanical laws to the relationships between the pressures inside the respiratory system (at the airway opening, alveolar, pleural, and muscular) and R aw, C L, and C CW. These relationships also are the basis of the different methods available to measure respiratory mechanics during spontaneous and artificial ventilation. Whereas a simple mechanical model (R aw, C L, and C CW) describes the basic understanding of ventilation mechanics, more complex concepts (nonlinearity, inhomogeneous ventilation, or viscoelasticity) should be employed to better describe and measure ventilation mechanics in patients.
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Affiliation(s)
- Ramon Farré
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina i Ciències de la Salut, Universitat de Barcelona, Barcelona, Spain
- CIBER de Enfermedades Respiratorias, Madrid, Spain
- Institut Investigacions Biomediques August Pi Sunyer, Barcelona, Spain
| | - Daniel Navajas
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina i Ciències de la Salut, Universitat de Barcelona, Barcelona, Spain
- CIBER de Enfermedades Respiratorias, Madrid, Spain
- Institut de Bioenginyeria de Catalunya (IBEC), The Barcelona Institute of Science and Technology, Barcelona, Spain
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Kiliç L, Tural Önür S, Gorek Dilektasli A, Ulubay G, Balcı A. Understanding the Impact of Pulmonary Rehabilitation on Airway Resistance in Patients with Severe COPD: A Single-Center Retrospective Study. Int J Chron Obstruct Pulmon Dis 2023; 18:1-10. [PMID: 36628301 PMCID: PMC9826605 DOI: 10.2147/copd.s384127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Accepted: 12/16/2022] [Indexed: 01/05/2023] Open
Abstract
Purpose We investigated the effect of pulmonary rehabilitation (PR) on airway resistance in chronic obstructive pulmonary disease (COPD) patients with severe airway obstruction and hyperinflation. Patients and Methods This retrospective cohort study was conducted with data from severe COPD cases with those who underwent an 8-week PR program. Main inclusion criteria were having severe airflow obstruction (defined as a forced expiratory volume in one second (FEV1) <50%) and plethysmographic evaluation findings being compatible with hyperinflation supporting the diagnosis of emphysema (presence of hyperinflation defined as functional residual capacity ratio of residual volume to total lung capacity (RV/TLC) >120%). Primary outcomes were airway resistance (Raw) and airway conductance (Gaw) which were measured by body plethysmography, and other measurements were performed, including 6-minute walk test (6-MWT), modified Medical Research Council dyspnea scale (mMRC) and COPD assessment test (CAT). Results Twenty-six severe and very severe COPD patients (FEV1, 35.0 ± 13.1%; RV/TLC, 163.5 ± 29.4) were included in the analyses, mean age 62.6 ± 5.8 years and 88.5% males. Following rehabilitation, significant improvements in total specific airway resistance percentage (sRawtot%, p = 0.040) and total specific airway conductance percentage (sGawtot%; p = 0.010) were observed. The post-rehabilitation mMRC scores and CAT values were significantly decreased compared to baseline results (p < 0.001 and p < 0.001, respectively). Although there were significant improvements in 6-MWT value (p < 0.001), exercise desaturation (ΔSaO2, p = 0.026), the changes in measured lung capacity and volume values were not significant. Conclusion We concluded that PR may have a positive effect on airway resistance and airway conductance in COPD patients with severe airflow obstruction.
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Affiliation(s)
- Lütfiye Kiliç
- Yedikule Chest Diseases and Thoracic Surgery Training and Research Hospital, Pulmonologist, Department of Pulmonary Rehabilitation, University of Health Sciences, Istanbul, Turkey,Correspondence: Lütfiye Kiliç, Yedikule Chest Diseases and Thoracic Surgery Training and Research Hospital, Istanbul, Turkey, Tel +90 532 397 7172, Email
| | - Seda Tural Önür
- Yedikule Chest Diseases and Thoracic Surgery Training and Research Hospital, Associate Professor, Department of Chest Diseases, University of Health Sciences, Istanbul, Turkey
| | - Aslı Gorek Dilektasli
- Uludağ University, Faculty of Medicine, Associate professor, Department of Chest Diseases, Bursa, Turkey
| | - Gaye Ulubay
- Başkent University, Faculty of Medicine, Professor, Department of Chest Diseases, Ankara, Turkey
| | - Arif Balcı
- Yedikule Chest Diseases and Thoracic Surgery Training and Research Hospital, Physiotherapist, Department of Pulmonary Rehabilitation, University of Health Sciences, Istanbul, Turkey
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Kaminsky DA, Irvin CG. The Physiology of Asthma-Chronic Obstructive Pulmonary Disease Overlap. Immunol Allergy Clin North Am 2022; 42:575-589. [DOI: 10.1016/j.iac.2022.04.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Inhibition of calcium-triggered secretion by hydrocarbon-stapled peptides. Nature 2022; 603:949-956. [PMID: 35322233 PMCID: PMC8967716 DOI: 10.1038/s41586-022-04543-1] [Citation(s) in RCA: 29] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Accepted: 02/11/2022] [Indexed: 02/06/2023]
Abstract
Membrane fusion triggered by Ca2+ is orchestrated by a conserved set of proteins to mediate synaptic neurotransmitter release, mucin secretion and other regulated exocytic processes1–4. For neurotransmitter release, the Ca2+ sensitivity is introduced by interactions between the Ca2+ sensor synaptotagmin and the SNARE complex5, and sequence conservation and functional studies suggest that this mechanism is also conserved for mucin secretion6. Disruption of Ca2+-triggered membrane fusion by a pharmacological agent would have therapeutic value for mucus hypersecretion as it is the major cause of airway obstruction in the pathophysiology of respiratory viral infection, asthma, chronic obstructive pulmonary disease and cystic fibrosis7–11. Here we designed a hydrocarbon-stapled peptide that specifically disrupts Ca2+-triggered membrane fusion by interfering with the so-called primary interface between the neuronal SNARE complex and the Ca2+-binding C2B domain of synaptotagmin-1. In reconstituted systems with these neuronal synaptic proteins or with their airway homologues syntaxin-3, SNAP-23, VAMP8, synaptotagmin-2, along with Munc13-2 and Munc18-2, the stapled peptide strongly suppressed Ca2+-triggered fusion at physiological Ca2+ concentrations. Conjugation of cell-penetrating peptides to the stapled peptide resulted in efficient delivery into cultured human airway epithelial cells and mouse airway epithelium, where it markedly and specifically reduced stimulated mucin secretion in both systems, and substantially attenuated mucus occlusion of mouse airways. Taken together, peptides that disrupt Ca2+-triggered membrane fusion may enable the therapeutic modulation of mucin secretory pathways. Peptides that disrupt Ca2+-triggered membrane fusion may enable the therapeutic modulation of mucin secretory pathways.
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Liu L, Ma H, Yuan S, Zhang J, Wu J, Dilimulati M, Wang Y, Shen S, Zhang L, Lin J, Yin Y. Prognosis of bronchial asthma in children with different pulmonary function phenotypes: A real-world retrospective observational study. Front Pediatr 2022; 10:1043047. [PMID: 36699301 PMCID: PMC9869064 DOI: 10.3389/fped.2022.1043047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Accepted: 12/20/2022] [Indexed: 01/11/2023] Open
Abstract
OBJECTIVE To follow up on the changes in pulmonary function phenotypes in children with asthma in the first year after diagnosis, and explore the risk factors of poor control in children with good treatment compliance. METHODS Children who were diagnosed with asthma in the Respiratory Department of Shanghai Children's Medical Center from January 1, 2019 to December 31, 2020 and were re-examined every 3 months after diagnosis for 1 year were continuously included, regardless of gender. We collected the clinical data, analyzed clinical characteristics of the different pulmonary function phenotypes at baseline and explored risk factors of poor asthma control after 1 year of standardized treatment. RESULTS A total of 142 children with asthma were included in this study, including 54 (38.0%) with normal pulmonary function phenotype (NPF), 75 (52.8%) with ventilation dysfunction phenotype (VD), and 13 (9.2%) with small airway dysfunction phenotype (SAD) in the baseline. Among them, there were statistically significant differences in all spirometry parameters, age, and course of disease before diagnosis (P < 0.05), and a negative correlation between age (r 2 = -0.33, P < 0.001), course of disease before diagnosis (r 2 = -0.23, P = 0.006) and FEV1/FVC. After 1-year follow-up, large airway function parameters and small airway function parameters were increased, fractional exhaled nitric oxide (FeNO) was decreased, the proportion of NPF was increased, the proportion of VD was decreased (P < 0.05), while there was no significant difference in the proportion of SAD. After 1 year of standardized treatment, 21 patients (14.8%) still had partly controlled or uncontrolled asthma. Our results showed that the more asthma attacks occurred within 1 year (OR = 6.249, 95% CI, 1.711-22.818, P = 0.006), the more times SAD presented at baseline and Assessment 1-4 (OR = 3.092, 95% CI, 1.222-7.825, P = 0.017), the higher the possibility of incomplete control of asthma. CONCLUSION About 15% of the children with good treatment compliance were still not completely controlled after 1 year of treatment, which is closely associated with persistent small airway dysfunction.
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Affiliation(s)
- Lu Liu
- Department of Respiratory Medicine, Shanghai Children's Medical Center, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Hui Ma
- Department of Respiratory Medicine, Shanghai Children's Medical Center, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Shuhua Yuan
- Department of Respiratory Medicine, Shanghai Children's Medical Center, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Jing Zhang
- Department of Respiratory Medicine, Shanghai Children's Medical Center, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Jinhong Wu
- Department of Respiratory Medicine, Shanghai Children's Medical Center, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Muheremu Dilimulati
- Department of Respiratory Medicine, Shanghai Children's Medical Center, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Yahua Wang
- Department of Respiratory Medicine, Shanghai Children's Medical Center, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Shiyu Shen
- Department of Respiratory Medicine, Shanghai Children's Medical Center, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Lei Zhang
- Department of Respiratory Medicine, Shanghai Children's Medical Center, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Jilei Lin
- Department of Respiratory Medicine, Shanghai Children's Medical Center, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Yong Yin
- Department of Respiratory Medicine, Shanghai Children's Medical Center, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
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Boucher M, Henry C, Khadangi F, Dufour-Mailhot A, Bossé Y. Double-chamber plethysmography versus oscillometry to detect baseline airflow obstruction in a model of asthma in two mouse strains. Exp Lung Res 2021; 47:390-401. [PMID: 34541979 DOI: 10.1080/01902148.2021.1979693] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
AIM OF THE STUDY The current gold standard to assess respiratory mechanics in mice is oscillometry, a technique from which several readouts of the respiratory system can be deduced, such as resistance and elastance. However, these readouts are often not altered in mouse models of asthma. This is in stark contrast with humans, where asthma is generally associated with alterations when assessed by either oscillometry or other techniques. In the present study, we have used double-chamber plethysmography (DCP) to evaluate the breathing pattern and the degree of airflow obstruction in a mouse model of asthma. MATERIALS AND METHODS Female C57BL/6 and BALB/c mice were studied at day 1 using DCP, as well as at day 11 using both DCP and oscillometry following a once-daily exposure to either house-dust mite (HDM) or saline for 10 consecutive days. RESULTS All DCP readouts used to describe either the breathing pattern (e.g., tidal volume and breathing frequency) or the degree of airflow obstruction (e.g., specific airway resistance) were different between mouse strains at day 1. Most of these strain differences persisted at day 11. Most oscillometric readouts (e.g., respiratory system resistance and elastance) were also different between strains. Changes caused by HDM were obvious with DCP, including decreases in tidal volume, minute ventilation, inspiratory time and mid-tidal expiratory flow and an increase in specific airway resistance. HDM also caused some strain specific alterations in breathing pattern, including increases in expiratory time and end inspiratory pause, which were only observed in C57BL/6 mice. Oscillometry also detected a small but significant increase in tissue elastance in HDM versus saline-exposed mice. CONCLUSIONS DCP successfully identified differences between C57BL/6 and BALB/c mice, as well as alterations in mice from both strains exposed to HDM. We conclude that, depending on the study purpose, DCP may sometimes outweigh oscillometry.
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Affiliation(s)
- Magali Boucher
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Quebec City, Canada
| | - Cyndi Henry
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Quebec City, Canada
| | - Fatemeh Khadangi
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Quebec City, Canada
| | - Alexis Dufour-Mailhot
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Quebec City, Canada
| | - Ynuk Bossé
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Quebec City, Canada
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Boucher M, Henry C, Dufour-Mailhot A, Khadangi F, Bossé Y. Smooth Muscle Hypocontractility and Airway Normoresponsiveness in a Mouse Model of Pulmonary Allergic Inflammation. Front Physiol 2021; 12:698019. [PMID: 34267677 PMCID: PMC8277197 DOI: 10.3389/fphys.2021.698019] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Accepted: 06/04/2021] [Indexed: 01/25/2023] Open
Abstract
The contractility of airway smooth muscle (ASM) is labile. Although this feature can greatly modulate the degree of airway responsiveness in vivo, the extent by which ASM's contractility is affected by pulmonary allergic inflammation has never been compared between strains of mice exhibiting a different susceptibility to develop airway hyperresponsiveness (AHR). Herein, female C57BL/6 and BALB/c mice were treated intranasally with either saline or house dust mite (HDM) once daily for 10 consecutive days to induce pulmonary allergic inflammation. The doses of HDM were twice greater in the less susceptible C57BL/6 strain. All outcomes, including ASM contractility, were measured 24 h after the last HDM exposure. As expected, while BALB/c mice exposed to HDM became hyperresponsive to a nebulized challenge with methacholine in vivo, C57BL/6 mice remained normoresponsive. The lack of AHR in C57BL/6 mice occurred despite exhibiting more than twice as much inflammation than BALB/c mice in bronchoalveolar lavages, as well as similar degrees of inflammatory cell infiltrates within the lung tissue, goblet cell hyperplasia and thickening of the epithelium. There was no enlargement of ASM caused by HDM exposure in either strain. Unexpectedly, however, excised tracheas derived from C57BL/6 mice exposed to HDM demonstrated a decreased contractility in response to both methacholine and potassium chloride, while tracheas from BALB/c mice remained normocontractile following HDM exposure. These results suggest that the lack of AHR in C57BL/6 mice, at least in an acute model of HDM-induced pulmonary allergic inflammation, is due to an acquired ASM hypocontractility.
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Affiliation(s)
- Magali Boucher
- Institut Universitaire de Cardiologie et de Pneumologie de Québec - Université Laval, Québec, QC, Canada
| | - Cyndi Henry
- Institut Universitaire de Cardiologie et de Pneumologie de Québec - Université Laval, Québec, QC, Canada
| | - Alexis Dufour-Mailhot
- Institut Universitaire de Cardiologie et de Pneumologie de Québec - Université Laval, Québec, QC, Canada
| | - Fatemeh Khadangi
- Institut Universitaire de Cardiologie et de Pneumologie de Québec - Université Laval, Québec, QC, Canada
| | - Ynuk Bossé
- Institut Universitaire de Cardiologie et de Pneumologie de Québec - Université Laval, Québec, QC, Canada
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Hopp RJ, Wilson MC, Pasha MA. Small Airway Disease in Pediatric Asthma: the Who, What, When, Where, Why, and How to Remediate. A Review and Commentary. Clin Rev Allergy Immunol 2020; 62:145-159. [PMID: 33241492 DOI: 10.1007/s12016-020-08818-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/29/2020] [Indexed: 12/18/2022]
Abstract
Asthma affects all portions of the airways. Small airways, however, comprise a substantial component of the conducting lung air flow. In asthma, inflammatory processes can affect the whole respiratory tract, from central to peripheral/small airways. The emphasis in adult and pediatric respiratory disease clinics is to focus on large airway obstruction and reversibility. This information, although valuable, underemphasizes a large portion of the conduction airway of asthmatics. Standard descriptions of asthma management focus on a multiple medication approaches. We particularly focused on the management of asthma in the international guidelines for the Global Initiative for Asthma (GINA). Overall, however, minimal attention is placed on the small airway pool in asthma medical management. We took the opportunity to thoroughly review and present specific data from the adult asthma literature which supported the concept that small airway abnormalities may play a role in the pathogenesis and clinical expression of asthma. Based on the conclusions of the adult asthma literature, we here present a thorough review of the literature as it relates to small airway disease in children with asthma. We used, collectively, individual data sources of data to expand the information available from standard diagnostic techniques, especially spirometry, in the evaluation of small airway disease. As the pharmacological approaches to moderate to severe asthma are advancing rapidly into the realm of biologics, we sought to present potential pharmacological options for small airway dysfunction in pediatrics prior to biological modifier intervention.
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Affiliation(s)
- Russell J Hopp
- Department of Pediatrics, University of Nebraska Medical Center and Children's Hospital and Medical Center, Omaha, NE, 68114, USA.
| | - Mark C Wilson
- Department of Pediatrics, University of Nebraska Medical Center and Children's Hospital and Medical Center, Omaha, NE, 68114, USA
| | - M Asghar Pasha
- Division of Allergy and Immunology, Albany Medical College, 176 Washington Avenue Extension, Suite 102, Albany, NY, 12203, USA
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12
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Chia SB, Nolin JD, Aboushousha R, Erikson C, Irvin CG, Poynter ME, van der Velden J, Taatjes DJ, van der Vliet A, Anathy V, Janssen-Heininger YMW. Glutaredoxin deficiency promotes activation of the transforming growth factor beta pathway in airway epithelial cells, in association with fibrotic airway remodeling. Redox Biol 2020; 37:101720. [PMID: 32971362 PMCID: PMC7509797 DOI: 10.1016/j.redox.2020.101720] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2020] [Revised: 09/02/2020] [Accepted: 09/11/2020] [Indexed: 12/14/2022] Open
Abstract
S-glutathionylation of reactive protein cysteines is a post-translational event that plays a critical role in transducing signals from oxidants into biological responses. S-glutathionylation can be reversed by the deglutathionylating enzyme glutaredoxin (GLRX). We have previously demonstrated that ablation of Glrx sensitizes mice to the development of parenchymal lung fibrosis(1). It remains unclear whether GLRX also controls airway fibrosis, a clinical feature relevant to asthma and chronic obstructive pulmonary disease, and whether GLRX controls the biology of airway epithelial cells, which have been implicated in the pathophysiology of these diseases. In the present study we utilized a house dust mite (HDM) model of allergic airway disease in wild type (WT) and Glrx-/- mice on a C57BL/6 background prone to develop airway fibrosis, and tracheal basal stem cells derived from WT mice, global Glrx-/- mice, or bi-transgenic mice allowing conditional ablation of the Glrx gene. Herein we show that absence of Glrx led to enhanced HDM-induced collagen deposition, elevated levels of transforming growth factor beta 1 (TGFB1) in the bronchoalveolar lavage, and resulted in increases in airway hyperresponsiveness. Airway epithelial cells isolated from Glrx-/- mice or following conditional ablation of Glrx showed spontaneous increases in secretion of TGFB1. Glrx-/- basal cells also showed spontaneous TGFB pathway activation, in association with increased expression of mesenchymal genes, including collagen 1a1 and fibronectin. Overall, these findings suggest that GLRX regulates airway fibrosis via a mechanism(s) that involve the plasticity of basal cells, the stem cells of the airways.
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Affiliation(s)
- Shi B Chia
- Department of Pathology and Laboratory Medicine, University of Vermont College of Medicine, Burlington, VT, 05405, USA
| | - James D Nolin
- Department of Pathology and Laboratory Medicine, University of Vermont College of Medicine, Burlington, VT, 05405, USA; Center for Genes, Environment and Health, National Jewish Health, Denver, CO, 80206, USA
| | - Reem Aboushousha
- Department of Pathology and Laboratory Medicine, University of Vermont College of Medicine, Burlington, VT, 05405, USA
| | - Cuixia Erikson
- Department of Pathology and Laboratory Medicine, University of Vermont College of Medicine, Burlington, VT, 05405, USA
| | - Charles G Irvin
- Department of Medicine, University of Vermont College of Medicine, Burlington, VT, 05405, USA
| | - Matthew E Poynter
- Department of Medicine, University of Vermont College of Medicine, Burlington, VT, 05405, USA
| | - Jos van der Velden
- Department of Pathology and Laboratory Medicine, University of Vermont College of Medicine, Burlington, VT, 05405, USA
| | - Douglas J Taatjes
- Department of Pathology and Laboratory Medicine, University of Vermont College of Medicine, Burlington, VT, 05405, USA
| | - Albert van der Vliet
- Department of Pathology and Laboratory Medicine, University of Vermont College of Medicine, Burlington, VT, 05405, USA
| | - Vikas Anathy
- Department of Pathology and Laboratory Medicine, University of Vermont College of Medicine, Burlington, VT, 05405, USA
| | - Yvonne M W Janssen-Heininger
- Department of Pathology and Laboratory Medicine, University of Vermont College of Medicine, Burlington, VT, 05405, USA.
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13
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Couetil L, Cardwell JM, Leguillette R, Mazan M, Richard E, Bienzle D, Bullone M, Gerber V, Ivester K, Lavoie JP, Martin J, Moran G, Niedźwiedź A, Pusterla N, Swiderski C. Equine Asthma: Current Understanding and Future Directions. Front Vet Sci 2020; 7:450. [PMID: 32903600 PMCID: PMC7438831 DOI: 10.3389/fvets.2020.00450] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Accepted: 06/19/2020] [Indexed: 12/12/2022] Open
Abstract
The 2019 Havemeyer Workshop brought together researchers and clinicians to discuss the latest information on Equine Asthma and provide future research directions. Current clinical and molecular asthma phenotypes and endotypes in humans were discussed and compared to asthma phenotypes in horses. The role of infectious and non-infectious causes of equine asthma, genetic factors and proposed disease pathophysiology were reviewed. Diagnostic limitations were evident by the limited number of tests and biomarkers available to field practitioners. The participants emphasized the need for more accessible, standardized diagnostics that would help identify specific phenotypes and endotypes in order to create more targeted treatments or management strategies. One important outcome of the workshop was the creation of the Equine Asthma Group that will facilitate communication between veterinary practice and research communities through published and easily accessible guidelines and foster research collaboration.
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Affiliation(s)
- Laurent Couetil
- College of Veterinary Medicine, Purdue University, West Lafayette, IN, United States
| | - Jacqueline M Cardwell
- Department of Pathobiology and Population Sciences, Royal Veterinary College, London, United Kingdom
| | - Renaud Leguillette
- College of Veterinary Medicine, University of Calgary, Calgary, AB, Canada
| | - Melissa Mazan
- Cummings School of Veterinary Medicine, Tufts University, Grafton, MA, United States
| | - Eric Richard
- LABÉO (Frank Duncombe), Normandie Université, UniCaen, Caen, France
| | - Dorothee Bienzle
- Department of Pathobiology, University of Guelph, Guelph, ON, Canada
| | - Michela Bullone
- Department of Veterinary Sciences, University of Turin, Grugliasco, Italy
| | - Vinzenz Gerber
- Vetsuisse Faculty, Institut Suisse de Médecine Équine (ISME), University of Bern and Agroscope, Bern, Switzerland
| | - Kathleen Ivester
- College of Veterinary Medicine, Purdue University, West Lafayette, IN, United States
| | - Jean-Pierre Lavoie
- Faculty of Veterinary Medicine, University of Montreal, Montreal, QC, Canada
| | - James Martin
- Meakins Christie Laboratories, McGill University Health Center Research Institute, Montreal, QC, Canada
| | - Gabriel Moran
- Department of Pharmacology, Faculty of Veterinary Sciences, Universidad Austral de Chile, Valdivia, Chile
| | - Artur Niedźwiedź
- Department of Internal Diseases With Clinic for Horses, Dogs and Cats, Wroclaw University of Environmental and Life Sciences, Wrocław, Poland
| | - Nicola Pusterla
- Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, Davis, CA, United States
| | - Cyprianna Swiderski
- College of Veterinary Medicine, Mississippi State University, Starkville, MS, United States
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14
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Abstract
This article will discuss in detail the pathophysiology of asthma from the point of view of lung mechanics. In particular, we will explain how asthma is more than just airflow limitation resulting from airway narrowing but in fact involves multiple consequences of airway narrowing, including ventilation heterogeneity, airway closure, and airway hyperresponsiveness. In addition, the relationship between the airway and surrounding lung parenchyma is thought to be critically important in asthma, especially as related to the response to deep inspiration. Furthermore, dynamic changes in lung mechanics over time may yield important information about asthma stability, as well as potentially provide a window into future disease control. All of these features of mechanical properties of the lung in asthma will be explained by providing evidence from multiple investigative methods, including not only traditional pulmonary function testing but also more sophisticated techniques such as forced oscillation, multiple breath nitrogen washout, and different imaging modalities. Throughout the article, we will link the lung mechanical features of asthma to clinical manifestations of asthma symptoms, severity, and control. © 2020 American Physiological Society. Compr Physiol 10:975-1007, 2020.
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Affiliation(s)
- David A Kaminsky
- University of Vermont Larner College of Medicine, Burlington, Vermont, USA
| | - David G Chapman
- University of Technology Sydney, Sydney, New South Wales, Australia
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15
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Irvin CG. The Flow-Volume Loop: Always an Inspiration! COPD 2020; 17:227-229. [PMID: 32506952 PMCID: PMC7401697 DOI: 10.1080/15412555.2020.1758050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Accepted: 04/14/2020] [Indexed: 10/24/2022]
Affiliation(s)
- Charles G Irvin
- Robert Larner MD College of Medicine, University of Vermont, Burlington, VT
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16
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Gazzola M, Flamand N, Bossé Y. [Extracellular molecules controlling the contraction of airway smooth muscle and their potential contribution to bronchial hyperresponsiveness]. Rev Mal Respir 2020; 37:462-473. [PMID: 32487422 DOI: 10.1016/j.rmr.2020.03.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Accepted: 03/12/2020] [Indexed: 02/06/2023]
Abstract
INTRODUCTION A significant portion of symptoms in some lung diseases results from an excessive constriction of airways due to the contraction of smooth muscle and bronchial hyperresponsiveness. A better understanding of the extracellular molecules that control smooth muscle contractility is necessary to identify the underlying causes of the problem. STATE OF KNOWLEDGE Almost a hundred molecules, some of which newly identified, influence the contractility of airway smooth muscle. While some molecules activate the contraction, others activate the relaxation, thus acting directly as bronchoconstrictors and bronchodilators, respectively. Other molecules do not affect contraction directly but rather influence it indirectly by modifying the effect of bronchoconstrictors and bronchodilators. These are called bronchomodulators. Some of these bronchomodulators increase the contractile effect of bronchoconstrictors and could thus contribute to bronchial hyperresponsiveness. PROSPECTS Considering the high number of molecules potentially involved, as well as the level of functional overlap between some of them, identifying the extracellular molecules responsible for excessive airway constriction in a patient is a major contemporary challenge.
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Affiliation(s)
| | | | - Y Bossé
- Université Laval, Québec, Canada.
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17
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Bhatia R, DiLullo KJ. Utility and efficiency of methacholine challenge testing in evaluating pediatric asthma: unraveling the diagnostic conundrum. J Asthma 2019; 58:69-74. [PMID: 31526153 DOI: 10.1080/02770903.2019.1663431] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
OBJECTIVE Interpretation of methacholine challenge testing (MCT) results depends on the patient's pretest probability of asthma as well as the provocative concentration (PC20); however, ordering providers rarely understand the complexity associated with its interpretation. This study investigated the clinical utility and efficiency of MCT at a tertiary center in evaluating pediatric asthma. METHODS Retrospective chart review was done for all MCT done at a tertiary center over a six year period (2011-2017). Demographics, referring provider, referral diagnosis, current symptoms with and without exercise, and baseline spirometry were collected. Pretest probability of asthma was assigned by author (RB) who was blinded to MCT results and PC20. Post-test probability of asthma was assigned based on pretest probability, MCT result (+/-), and PC20. Three assigned asthma probability categories were "unlikely" "likely", and "very likely". RESULTS Of 172 subjects (91 Females, age range 5-21 years), 64.9% of MCT results (n = 111)) were negative and 35.1% (n = 60)) were positive. One was inconclusive. Those who tested positive were shorter, lighter, younger and had lower forced expiratory volume in one second/forced vital capacity (FEV1/FVC) ratio than those who tested negative (p < 0.05). Subjects with exercise symptoms only were less likely to test positive (OR 0.2, CI 0.1-0.5). In a majority of subjects (91.8%; 157/171), MCT increased the certainty of presence or absence of asthma. CONCLUSIONS In our subject population, MCT could be useful in evaluating pediatric asthma if subject's pretest probability of asthma and PC20 was taken into account. It was not as useful for subjects with exercise symptoms only.
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Affiliation(s)
- Rajeev Bhatia
- Department of Pediatrics, Division of Pulmonology, Akron Children's Hospital, Akron, OH, USA
| | - Kelly J DiLullo
- Department of Pediatrics, Division of Pulmonology, Akron Children's Hospital, Akron, OH, USA
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18
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Polio SR, Stasiak SE, Jamieson RR, Balestrini JL, Krishnan R, Parameswaran H. Extracellular matrix stiffness regulates human airway smooth muscle contraction by altering the cell-cell coupling. Sci Rep 2019; 9:9564. [PMID: 31267003 PMCID: PMC6606622 DOI: 10.1038/s41598-019-45716-9] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2018] [Accepted: 06/13/2019] [Indexed: 12/31/2022] Open
Abstract
For an airway or a blood vessel to narrow, there must be a connected path that links the smooth muscle (SM) cells with each other, and transmits forces around the organ, causing it to constrict. Currently, we know very little about the mechanisms that regulate force transmission pathways in a multicellular SM ensemble. Here, we used extracellular matrix (ECM) micropatterning to study force transmission in a two-cell ensemble of SM cells. Using the two-SM cell ensemble, we demonstrate (a) that ECM stiffness acts as a switch that regulates whether SM force is transmitted through the ECM or through cell-cell connections. (b) Fluorescent imaging for adherens junctions and focal adhesions show the progressive loss of cell-cell borders and the appearance of focal adhesions with the increase in ECM stiffness (confirming our mechanical measurements). (c) At the same ECM stiffness, we show that the presence of a cell-cell border substantially decreases the overall contractility of the SM cell ensemble. Our results demonstrate that connectivity among SM cells is a critical factor to consider in the development of diseases such as asthma and hypertension.
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Affiliation(s)
- Samuel R Polio
- Department of Bioengineering, Northeastern University, Boston, MA, 02115, USA
| | - Suzanne E Stasiak
- Department of Bioengineering, Northeastern University, Boston, MA, 02115, USA
| | - Ryan R Jamieson
- Department of Bioengineering, Northeastern University, Boston, MA, 02115, USA
| | - Jenna L Balestrini
- Department of Biomedical Engineering, Yale University, New Haven, CT, USA
| | - Ramaswamy Krishnan
- Department of Emergency Medicine, Beth Israel Deaconess Medical Center, Boston, MA, 02115, USA
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19
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Piqué N, De Servi B. Rhinosectan ® spray (containing xyloglucan) on the ciliary function of the nasal respiratory epithelium; results of an in vitro study. Allergy Asthma Clin Immunol 2018; 14:41. [PMID: 30337943 PMCID: PMC6174573 DOI: 10.1186/s13223-018-0268-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Accepted: 05/23/2018] [Indexed: 12/19/2022] Open
Abstract
Background To assess the effects of Rhinosectan® spray, a medical device containing xyloglucan, on nasal ciliary function (in MucilAir™Nasal cells). Methods MucilAir™Nasal, a three-dimensional organotypic airway tissue model (with different cell types), was treated with Rhinosectan® (30 µl) or with a control (saline solution). The effects of Rhinosectan® were evaluated at 15 and 60 min post-exposure by: measurement of the cilia beating frequency (Hz), mucin detection (Enzyme-Linked Lectin Assay—ELLA), mucociliary clearance (µm/s) and phagocytosis assay (fluorescence). Results Exposure of MucilAir™ to Rhinosectan® did not alter the cilia beating frequency at 15 and 60 min post-exposure (diluted and undiluted). Exposure to Rhinosectan® (undiluted) during 60 min increased mucociliary clearance (93.3 ± 2.1 µm/s vs. 80.9 ± 1.8 µm/s; p < 0.01) and phagocytic activity (1.89-fold increase) in comparison with saline solution. Moreover, a significant decrease in mucin concentration was observed after 15 min of exposure (171.4 ng/ml vs. 306.5 ng/ml; p < 0.01) and at 60 min post-treatment (242.7 ng/ml vs. 339 ng/ml; p < 0.05). Conclusions The application of Rhinosectan® to nasal epithelial cells does not impair ciliary movement, enhances mucociliary clearance and facilitates phagocytosis while reducing mucin secretion, which are optimal properties for the management of rhinitis and associated conditions.
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Affiliation(s)
- Núria Piqué
- 1Department of Microbiology and Parasitology, Pharmacy Faculty, Universitat de Barcelona (UB), Diagonal Sud, Facultat de Farmàcia, Edifici A, Av Joan XXIII, 27-31, 08028 Barcelona, Spain.,2Institut de Recerca en Nutrició i Seguretat Alimentària de la UB (INSA-UB), Universitat de Barcelona, Barcelona, Spain
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20
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Lortie K, Maheux C, Gendron D, Langlois A, Beaulieu MJ, Marsolais D, Bossé Y, Blanchet MR. CD34 Differentially Regulates Contractile and Noncontractile Elements of Airway Reactivity. Am J Respir Cell Mol Biol 2018; 58:79-88. [PMID: 28850257 DOI: 10.1165/rcmb.2017-0008oc] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Airway hyperresponsiveness (AHR), a major hallmark of asthma, results from alterations of contractile and noncontractile elements of airway reactivity. CD34 is a sialomucin that is expressed on various cells involved in asthma, such as eosinophils and airway smooth muscle precursors, highlighting its potential influence in AHR. To study the role of CD34 in regulating the contractile and noncontractile elements of AHR, AHR was induced by chronic exposure to house dust mite (HDM) antigen. To assess the role of CD34 on the contractile elements of AHR, airway reactivity and airway smooth muscle contractility in response to methacholine were measured. To assess CD34's role in regulating the noncontractile elements of AHR, a chimeric mouse model was used to determine the impact of CD34 expression on inflammatory versus microenvironmental cells in AHR development. Extracellular matrix production, mucus production, and mast cell degranulation were also measured. Whereas wild-type mice developed AHR in response to HDM, a loss of airway reactivity was observed in Cd34-/- mice 24 hours after the last exposure to HDM compared with naive controls. This was reversed when airway reactivity was measured 1 week after the last HDM exposure. Additionally, mast cell degranulation and mucus production were altered in the absence of CD34 expression. Importantly, simultaneous expression of CD34 on cells originating from the hematopoietic compartment and the microenvironment was needed for expression of this phenotype. These results provide evidence that CD34 is required for AHR and airway reactivity maintenance in the early days after an inflammatory episode in asthma.
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Affiliation(s)
- Katherine Lortie
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, Quebec, Canada
| | - Catherine Maheux
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, Quebec, Canada
| | - David Gendron
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, Quebec, Canada
| | - Anick Langlois
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, Quebec, Canada
| | - Marie-Josée Beaulieu
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, Quebec, Canada
| | - David Marsolais
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, Quebec, Canada
| | - Ynuk Bossé
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, Quebec, Canada
| | - Marie-Renée Blanchet
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, Quebec, Canada
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21
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Gazzola M, Mailhot-Larouche S, Beucher C, Bossé Y. The underlying physiological mechanisms whereby anticholinergics alleviate asthma. Can J Physiol Pharmacol 2018; 96:433-441. [PMID: 29414243 DOI: 10.1139/cjpp-2017-0448] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The mechanisms whereby anticholinergics improve asthma outcomes, such as lung function, symptoms, and rate of exacerbation, can be numerous. The most obvious is by affecting the contraction of airway smooth muscle (ASM). The acetylcholine released from the cholinergic nerves is the most important bronchoconstrictor that sets the baseline degree of contractile activation of ASM in healthy individuals. Although the degree of ASM's contractile activation can also be fine-tuned by a plethora of other bronchoconstrictors and bronchodilators in asthma, blocking the ceaseless effect of acetylcholine on ASM by anticholinergics reduces, at any given moment, the overall degree of contractile activation. Because the relationships that exist between the degree of contractile activation, ASM force, ASM shortening, airway narrowing, airflow resistance, and respiratory resistance are not linear, small decreases in the contractile activation of ASM can be greatly amplified and thus translate into important benefits to a patient's well-being. Plus, many inflammatory and remodeling features that are often found in asthmatic lungs synergize with the contractile activation of ASM to increase respiratory resistance. This review recalls that the proven effectiveness of anticholinergics in the treatment of asthma could be merely attributed to a small reduction in the contractile activation of ASM.
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Affiliation(s)
- Morgan Gazzola
- Quebec Heart and Lung Institute, affiliated with Université Laval, Quebec City, Quebec G1V 4G5, Canada.,Quebec Heart and Lung Institute, affiliated with Université Laval, Quebec City, Quebec G1V 4G5, Canada
| | - Samuel Mailhot-Larouche
- Quebec Heart and Lung Institute, affiliated with Université Laval, Quebec City, Quebec G1V 4G5, Canada.,Quebec Heart and Lung Institute, affiliated with Université Laval, Quebec City, Quebec G1V 4G5, Canada
| | - Clémentine Beucher
- Quebec Heart and Lung Institute, affiliated with Université Laval, Quebec City, Quebec G1V 4G5, Canada.,Quebec Heart and Lung Institute, affiliated with Université Laval, Quebec City, Quebec G1V 4G5, Canada
| | - Ynuk Bossé
- Quebec Heart and Lung Institute, affiliated with Université Laval, Quebec City, Quebec G1V 4G5, Canada.,Quebec Heart and Lung Institute, affiliated with Université Laval, Quebec City, Quebec G1V 4G5, Canada
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22
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Georas SN. All plugged up - noninvasive mucus score to assess airway dysfunction in asthma. J Clin Invest 2018; 128:906-909. [PMID: 29400694 DOI: 10.1172/jci99726] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Asthma is remarkably heterogeneous, and there are multiple underlying inflammatory pathways and structural airway abnormalities that lead to symptomatic disease. Consequently, a current challenge in the field is to precisely characterize different types of asthma, with the goal of developing personalized approaches to therapy. In the current issue of the JCI, Dunican et al. developed a noninvasive way to assess airway dysfunction in asthma by measuring mucus accumulation using multidetector computed tomography (MDCT) and found that mucus plugging of small airways was remarkably common in subjects with severe asthma. This work highlights the importance of noninvasive imaging approaches in defining specific asthma subsets and guiding targeted therapies.
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23
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Salvianolic acid B improves airway hyperresponsiveness by inhibiting MUC5AC overproduction associated with Erk1/2/P38 signaling. Eur J Pharmacol 2018; 824:30-39. [PMID: 29382534 DOI: 10.1016/j.ejphar.2018.01.050] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Revised: 01/22/2018] [Accepted: 01/26/2018] [Indexed: 12/13/2022]
Abstract
Salvianolic acid B (SalB) is one of the main water-soluble composites from Chinese medicine Dansen (Radix miltiorrhiza). It is used for clinical treatment of various diseases including cardiovascular, lung, Liver, renal and cancers. However, the effects of SalB to allergy induced airway mucin hypersecretion, inflammation and hyperresponsiveness (AHR) remains not clear. Overproduction of airway MUC5AC is a central effector of inflammation that is strongly associated with AHR in asthmatic attack. In this study, we investigated the anti-asthmatic activity and mechanism of SalB in a murine model and human epithelial cells by monitoring changes in mucin expression and secretion, airway inflammation, AHR, and signaling pathways. SalB was administered by intragastric administration (i.g) daily for a week, starting at 21 days after sensitization of ovalbumin (OVA). All examinations were performed 24h after the last antigen challenge. We found that treatments with SalB significantly inhibited increase in the tracheobronchial secretion, glycosaminoglycan levels, interleukin (IL)-13, IL-4, and IL-5 cytokines mRNA and protein expression, and decrease in mucociliary clearance in lung tissues. Histological results demonstrated that SalB attenuated OVA-induced eosinophil infiltration, airway goblet cell hyperplasia, and MUC5AC and MUC5B mRNA and protein expression in lung tissues. SalB exhibited protective effects against AHR in OVA-challenged animals. In vitro, SalB significantly inhibited IL-13-induced MUC5AC and MUC5B mRNA and protein expression in human epithelial cells. These effects were blocked by SalB by downregulating the Erk1/2 and P38 signaling pathways. Taken together, these data indicate that treatment with SalB may improve AHR by inhibiting MUC5AC overproduction.
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24
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Nolin JD, Lai Y, Ogden HL, Manicone AM, Murphy RC, An D, Frevert CW, Ghomashchi F, Naika GS, Gelb MH, Gauvreau GM, Piliponsky AM, Altemeier WA, Hallstrand TS. Secreted PLA2 group X orchestrates innate and adaptive immune responses to inhaled allergen. JCI Insight 2017; 2:94929. [PMID: 29093264 PMCID: PMC5752296 DOI: 10.1172/jci.insight.94929] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Accepted: 09/26/2017] [Indexed: 01/15/2023] Open
Abstract
Phospholipase A2 (PLA2) enzymes regulate the formation of eicosanoids and lysophospholipids that contribute to allergic airway inflammation. Secreted PLA2 group X (sPLA2-X) was recently found to be increased in the airways of asthmatics and is highly expressed in airway epithelial cells and macrophages. In the current study, we show that allergen exposure increases sPLA2-X in humans and in mice, and that global deletion of Pla2g10 results in a marked reduction in airway hyperresponsiveness (AHR), eosinophil and T cell trafficking to the airways, airway occlusion, generation of type-2 cytokines by antigen-stimulated leukocytes, and antigen-specific immunoglobulins. Further, we found that Pla2g10-/- mice had reduced IL-33 levels in BALF, fewer type-2 innate lymphoid cells (ILC2s) in the lung, less IL-33-induced IL-13 expression in mast cells, and a marked reduction in both the number of newly recruited macrophages and the M2 polarization of these macrophages in the lung. These results indicate that sPLA2-X serves as a central regulator of both innate and adaptive immune response to proteolytic allergen.
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Affiliation(s)
- James D. Nolin
- Department of Medicine, Division of Pulmonary and Critical Care
| | - Ying Lai
- Department of Medicine, Division of Pulmonary and Critical Care
| | | | | | - Ryan C. Murphy
- Department of Medicine, Division of Pulmonary and Critical Care
| | - Dowon An
- Department of Medicine, Division of Pulmonary and Critical Care
| | - Charles W. Frevert
- Department of Medicine, Division of Pulmonary and Critical Care
- Department of Comparative Medicine
| | | | | | - Michael H. Gelb
- Department of Chemistry, and
- Department of Biochemistry, University of Washington, Seattle, Washington, USA
| | - Gail M. Gauvreau
- Department of Medicine, McMaster University, Hamilton, Ontario, Canada
| | - Adrian M. Piliponsky
- Center for Immunity and Immunotherapies, Seattle Children’s Research Institute, Seattle, Washington, USA
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25
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Bullone M, Vargas A, Elce Y, Martin JG, Lavoie JP. Fluticasone/salmeterol reduces remodelling and neutrophilic inflammation in severe equine asthma. Sci Rep 2017; 7:8843. [PMID: 28821845 PMCID: PMC5562887 DOI: 10.1038/s41598-017-09414-8] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Accepted: 07/24/2017] [Indexed: 12/11/2022] Open
Abstract
Asthmatic airways are inflamed and undergo remodelling. Inhaled corticosteroids and long-acting β2-agonist combinations are more effective than inhaled corticosteroid monotherapy in controlling disease exacerbations, but their effect on airway remodelling and inflammation remains ill-defined. This study evaluates the contribution of inhaled fluticasone and salmeterol, alone or combined, to the reversal of bronchial remodelling and inflammation. Severely asthmatic horses (6 horses/group) were treated with fluticasone, salmeterol, fluticasone/salmeterol, or with antigen avoidance for 12 weeks. Lung function, central and peripheral airway remodelling, and bronchoalveolar inflammation were assessed. Fluticasone/salmeterol and fluticasone monotherapy decreased peripheral airway smooth muscle remodelling after 12 weeks (p = 0.007 and p = 0.02, respectively). On average, a 30% decrease was observed with both treatments. In central airways, fluticasone/salmeterol reversed extracellular matrix remodelling after 12 weeks, both within the lamina propria (decreased thickness, p = 0.005) and within the smooth muscle layer (p = 0.004). Only fluticasone/salmeterol decreased bronchoalveolar neutrophilia (p = 0.03) to the same extent as antigen avoidance already after 8 weeks. In conclusion, this study shows that fluticasone/salmeterol combination decreases extracellular matrix remodelling in central airways and intraluminal neutrophilia. Fluticasone/salmeterol and fluticasone monotherapy equally reverse peripheral airway smooth muscle remodelling.
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Affiliation(s)
- Michela Bullone
- Université de Montréal, Faculty of Veterinary Medicine, Department of Clinical Sciences, 3200 rue Sicotte, St-Hyacinthe, J2S 2M2, Quebec, Canada
| | - Amandine Vargas
- Université de Montréal, Faculty of Veterinary Medicine, Department of Clinical Sciences, 3200 rue Sicotte, St-Hyacinthe, J2S 2M2, Quebec, Canada
| | - Yvonne Elce
- Université de Montréal, Faculty of Veterinary Medicine, Department of Clinical Sciences, 3200 rue Sicotte, St-Hyacinthe, J2S 2M2, Quebec, Canada.,University of Edinburgh, Royal (Dick) School of Veterinary Studies, Easter Bush Campus, EH25 9RG, United Kingdom
| | - James G Martin
- McGill University, Meakins Christie Laboratories, McGill University Health Center Research Institute, 1001 Decarie Blvd, Montreal, H4A 3J1, Quebec, Canada
| | - Jean-Pierre Lavoie
- Université de Montréal, Faculty of Veterinary Medicine, Department of Clinical Sciences, 3200 rue Sicotte, St-Hyacinthe, J2S 2M2, Quebec, Canada.
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26
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Coates AL, Wanger J, Cockcroft DW, Culver BH, Carlsen KH, Diamant Z, Gauvreau G, Hall GL, Hallstrand TS, Horvath I, de Jongh FH, Joos G, Kaminsky DA, Laube B, Leuppi JD, Sterk PJ. ERS technical standard on bronchial challenge testing: general considerations and performance of methacholine challenge tests. Eur Respir J 2017; 49:49/5/1601526. [DOI: 10.1183/13993003.01526-2016] [Citation(s) in RCA: 161] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2016] [Accepted: 01/15/2017] [Indexed: 11/05/2022]
Abstract
This international task force report updates general considerations for bronchial challenge testing and the performance of the methacholine challenge test. There are notable changes from prior recommendations in order to accommodate newer delivery devices. Rather than basing the test result upon a methacholine concentration (provocative concentration (PC20) causing a 20% fall in forced expiratory volume in 1 s (FEV1)), the new recommendations base the result upon the delivered dose of methacholine causing a 20% fall in FEV1 (provocative dose (PD20)). This end-point allows comparable results from different devices or protocols, thus any suitable nebuliser or dosimeter may be used, so long as the delivery characteristics are known. Inhalation may be by tidal breathing using a breath-actuated or continuous nebuliser for 1 min (or more), or by a dosimeter with a suitable breath count. Tests requiring maximal inhalations to total lung capacity are not recommended because the bronchoprotective effect of a deep breath reduces the sensitivity of the test.
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27
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Targeting Single Molecules in Asthma Benefits Few. Trends Mol Med 2016; 22:935-945. [PMID: 27692867 DOI: 10.1016/j.molmed.2016.09.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2016] [Revised: 09/07/2016] [Accepted: 09/07/2016] [Indexed: 01/05/2023]
Abstract
Asthma is a lung disorder triggered by various airborne factors in susceptible individuals. Although generally controlled, asthma can be severe and difficult to treat. Presently, increasing numbers of pharmaceuticals capable of blocking or mimicking specific endogenous molecules are undergoing clinical trials in asthmatic individuals whose symptoms are poorly controlled despite adherence to guideline therapies. Unfortunately, only a few, meticulously selected patients have been found to minimally benefit. These findings not only confirm that the molecular pathogenesis of severe asthma is variable between patients but also suggest that each molecular defect is likely to contribute little on its own in each patient. We opine that therapies targeting a specific molecular defect are predestined to yield marginal effects in the treatment of severe asthma.
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28
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Szigeti K, Szabó T, Korom C, Czibak I, Horváth I, Veres DS, Gyöngyi Z, Karlinger K, Bergmann R, Pócsik M, Budán F, Máthé D. Radiomics-based differentiation of lung disease models generated by polluted air based on X-ray computed tomography data. BMC Med Imaging 2016; 16:14. [PMID: 26864653 PMCID: PMC4750279 DOI: 10.1186/s12880-016-0118-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Accepted: 02/01/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Lung diseases (resulting from air pollution) require a widely accessible method for risk estimation and early diagnosis to ensure proper and responsive treatment. Radiomics-based fractal dimension analysis of X-ray computed tomography attenuation patterns in chest voxels of mice exposed to different air polluting agents was performed to model early stages of disease and establish differential diagnosis. METHODS To model different types of air pollution, BALBc/ByJ mouse groups were exposed to cigarette smoke combined with ozone, sulphur dioxide gas and a control group was established. Two weeks after exposure, the frequency distributions of image voxel attenuation data were evaluated. Specific cut-off ranges were defined to group voxels by attenuation. Cut-off ranges were binarized and their spatial pattern was associated with calculated fractal dimension, then abstracted by the fractal dimension -- cut-off range mathematical function. Nonparametric Kruskal-Wallis (KW) and Mann-Whitney post hoc (MWph) tests were used. RESULTS Each cut-off range versus fractal dimension function plot was found to contain two distinctive Gaussian curves. The ratios of the Gaussian curve parameters are considerably significant and are statistically distinguishable within the three exposure groups. CONCLUSIONS A new radiomics evaluation method was established based on analysis of the fractal dimension of chest X-ray computed tomography data segments. The specific attenuation patterns calculated utilizing our method may diagnose and monitor certain lung diseases, such as chronic obstructive pulmonary disease (COPD), asthma, tuberculosis or lung carcinomas.
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Affiliation(s)
- Krisztián Szigeti
- Department of Biophysics and Radiation Biology, Semmelweis University, Tűzoltó utca 37-47, Budapest, H-1094, Hungary.
| | - Tibor Szabó
- CROmed Translational Research Centers Ltd., Baross utca 91-95, Budapest, H-1047, Hungary
| | - Csaba Korom
- Department of Radiology and Oncotherapy, Semmelweis University, Üllői út 78/A, Budapest, H-1082, Hungary.
| | - Ilona Czibak
- CROmed Translational Research Centers Ltd., Baross utca 91-95, Budapest, H-1047, Hungary.
| | - Ildikó Horváth
- Department of Biophysics and Radiation Biology, Semmelweis University, Tűzoltó utca 37-47, Budapest, H-1094, Hungary.
| | - Dániel S Veres
- Department of Biophysics and Radiation Biology, Semmelweis University, Tűzoltó utca 37-47, Budapest, H-1094, Hungary.
| | - Zoltán Gyöngyi
- Department of Public Health Medicine, University of Pécs, Szigeti út 12, Pécs, H-7624, Hungary.
| | - Kinga Karlinger
- Department of Radiology and Oncotherapy, Semmelweis University, Üllői út 78/A, Budapest, H-1082, Hungary.
| | - Ralf Bergmann
- Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf, Dresden, D-01314, Germany.
| | - Márta Pócsik
- CROmed Translational Research Centers Ltd., Baross utca 91-95, Budapest, H-1047, Hungary.
| | - Ferenc Budán
- Department of Public Health Medicine, University of Pécs, Szigeti út 12, Pécs, H-7624, Hungary. .,MedProDevelop Kft, Irgalmasok utcája 16, Pécs, H-7621, Hungary.
| | - Domokos Máthé
- Department of Biophysics and Radiation Biology, Semmelweis University, Tűzoltó utca 37-47, Budapest, H-1094, Hungary. .,CROmed Translational Research Centers Ltd., Baross utca 91-95, Budapest, H-1047, Hungary.
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29
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Auger L, Mailhot-Larouche S, Tremblay F, Poirier M, Farah C, Bossé Y. The contractile lability of smooth muscle in asthmatic airway hyperresponsiveness. Expert Rev Respir Med 2015; 10:19-27. [PMID: 26561333 DOI: 10.1586/17476348.2016.1111764] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The contractile capacity of airway smooth muscle is not fixed but modulated by an impressive number of extracellular inflammatory mediators. Targeting the transient component of airway hyperresponsiveness ascribed to this contractile lability of ASM is a quest of great promises in order to alleviate asthma symptoms during inflammatory flares. However, owing to the plethora of mediators putatively involved and the molecular heterogeneity of asthma, it is more likely that many mediators conspire to increase the contractile capacity of ASM, each of which contributing to a various extent and in a time-varying fashion in individuals suffering from asthma. The task of identifying a common mend for a tissue rendered hypercontractile by imponderable assortments of inflammatory mediators is puzzling.
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Affiliation(s)
- Laurence Auger
- a Institut Universitaire de Cardiologie et de Pneumologie de Québec , Université Laval , Québec , Canada
| | - Samuel Mailhot-Larouche
- a Institut Universitaire de Cardiologie et de Pneumologie de Québec , Université Laval , Québec , Canada
| | - Francis Tremblay
- a Institut Universitaire de Cardiologie et de Pneumologie de Québec , Université Laval , Québec , Canada
| | - Mathilde Poirier
- a Institut Universitaire de Cardiologie et de Pneumologie de Québec , Université Laval , Québec , Canada
| | - Claude Farah
- a Institut Universitaire de Cardiologie et de Pneumologie de Québec , Université Laval , Québec , Canada
| | - Ynuk Bossé
- a Institut Universitaire de Cardiologie et de Pneumologie de Québec , Université Laval , Québec , Canada
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30
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Abstract
Bronchial thermoplasty (BT) is a novel therapy for patients with severe asthma. Using radio frequency thermal energy, it aims to reduce the airway smooth muscle mass. Several clinical trials have demonstrated improvements in asthma-related quality of life and a reduction in the number of exacerbations following treatment with BT. In addition, recent data has demonstrated the long-term safety of the procedure as well as sustained improvements in rates of asthma exacerbations, reduction in health care utilization, and improved quality of life. Further study is needed to elucidate the underlying mechanisms that result in these improvements. In addition, improved characterization of the asthma subphenotypes likely to exhibit the largest clinical benefit is a critical step in determining the precise role of BT in the management of severe asthma.
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Affiliation(s)
- Balaji Laxmanan
- Section of Pulmonary and Critical Care Medicine, University of Chicago Medicine, Chicago, IL, USA
| | - D Kyle Hogarth
- Section of Pulmonary and Critical Care Medicine, University of Chicago Medicine, Chicago, IL, USA
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31
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The polymeric mucin Muc5ac is required for allergic airway hyperreactivity. Nat Commun 2015; 6:6281. [PMID: 25687754 PMCID: PMC4333679 DOI: 10.1038/ncomms7281] [Citation(s) in RCA: 208] [Impact Index Per Article: 23.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2014] [Accepted: 01/13/2015] [Indexed: 01/05/2023] Open
Abstract
In asthma, airflow obstruction is thought to result primarily from inflammation-triggered airway smooth muscle (ASM) contraction. However, anti-inflammatory and smooth muscle-relaxing treatments are often temporary or ineffective. Overproduction of the mucin MUC5AC is an additional disease feature that, while strongly associated pathologically, is poorly understood functionally. Here we show that Muc5ac is a central effector of allergic inflammation that is required for airway hyperreactivity (AHR) to methacholine (MCh). In mice bred on two well-characterized strain backgrounds (C57BL/6 and BALB/c) and exposed to two separate allergic stimuli (ovalbumin and Aspergillus extract), genetic removal of Muc5ac abolishes AHR. Residual MCh responses are identical to unchallenged controls, and although inflammation remains intact, heterogeneous mucous occlusion decreases by 74%. Thus, whereas inflammatory effects on ASM alone are insufficient for AHR, Muc5ac-mediated plugging is an essential mechanism. Inhibiting MUC5AC may be effective for treating asthma and other lung diseases where it is also overproduced.
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32
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Lee-Gosselin A, Gendron D, Blanchet MR, Marsolais D, Bossé Y. The gain of smooth muscle's contractile capacity induced by tone on in vivo airway responsiveness in mice. J Appl Physiol (1985) 2015; 118:692-8. [PMID: 25571989 DOI: 10.1152/japplphysiol.00645.2014] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Airway hyperresponsiveness to a spasmogenic challenge such as methacholine, and an increased baseline tone measured by the reversibility of airway obstruction with a bronchodilator, are two common features of asthma. However, whether the increased tone influences the degree of airway responsiveness to a spasmogen is unclear. Herein, we hypothesized that increased tone augments airway responsiveness in vivo by increasing the contractile capacity of airway smooth muscle (ASM). Anesthetized, tracheotomized, paralyzed, and mechanically ventilated mice were either exposed (experimental group) or not (control group) to tone for 20 min, which was elicited by nebulizing serial small doses of methacholine. Respiratory system resistance was monitored during this period and the peak response to a large cumulative dose of methacholine was then measured at the end of 20 min to assess and compare the level of airway responsiveness between groups. To confirm direct ASM involvement, the contractile capacity of excised murine tracheas was measured with and without preexposure to tone elicited by either methacholine or a thromboxane A2 mimetic (U46619). Distinct spasmogens were tested because the spasmogens liable for increased tone in asthma are likely to differ. The results indicate that preexposure to tone increases airway responsiveness in vivo by 126 ± 37% and increases the contractile capacity of excised tracheas ex vivo by 23 ± 4% for methacholine and 160 ± 63% for U46619. We conclude that an increased tone, regardless of whether it is elicited by a muscarinic agonist or a thromboxane A2 mimetic, may contribute to airway hyperresponsiveness by increasing the contractile capacity of ASM.
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Affiliation(s)
- Audrey Lee-Gosselin
- Institut universitaire de cardiologie et de pneumologie de Québec, Université Laval, Québec, Québec, Canada
| | - David Gendron
- Institut universitaire de cardiologie et de pneumologie de Québec, Université Laval, Québec, Québec, Canada
| | - Marie-Renée Blanchet
- Institut universitaire de cardiologie et de pneumologie de Québec, Université Laval, Québec, Québec, Canada
| | - David Marsolais
- Institut universitaire de cardiologie et de pneumologie de Québec, Université Laval, Québec, Québec, Canada
| | - Ynuk Bossé
- Institut universitaire de cardiologie et de pneumologie de Québec, Université Laval, Québec, Québec, Canada
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33
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Chapman DG, Pascoe CD, Lee-Gosselin A, Couture C, Seow CY, Paré PD, Salome CM, King GG, Bossé Y. Smooth Muscle in the Maintenance of Increased Airway Resistance Elicited by Methacholine in Humans. Am J Respir Crit Care Med 2014; 190:879-85. [DOI: 10.1164/rccm.201403-0502oc] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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Abstract
Asthma is a prevalent respiratory disorder triggered by a variety of inhaled environmental factors, such as allergens, viruses, and pollutants. Asthma is characterized by an elevated activation of the smooth muscle surrounding the airways, as well as a propensity of the airways to narrow excessively in response to a spasmogen (i.e. contractile agonist), a feature called airway hyperresponsiveness. The level of airway smooth muscle (ASM) activation is putatively controlled by mediators released in its vicinity. In asthma, many mediators that affect ASM contractility originate from inflammatory cells that are mobilized into the airways, such as eosinophils. However, mounting evidence indicates that mediators released by remote organs can also influence the level of activation of ASM, as well as its level of responsiveness to spasmogens and relaxant agonists. These remote mediators are transported through circulating blood to act either directly on ASM or indirectly via the nervous system by tuning the level of cholinergic activation of ASM. Indeed, mediators generated from diverse organs, including the adrenals, pancreas, adipose tissue, gonads, heart, intestines, and stomach, affect the contractility of ASM. Together, these results suggest that, apart from a paracrine mode of regulation, ASM is subjected to an endocrine mode of regulation. The results also imply that defects in organs other than the lungs can contribute to asthma symptoms and severity. In this review, I suggest that the endocrine mode of regulation of ASM contractility is overlooked.
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Affiliation(s)
- Ynuk Bossé
- Institut Universitaire de Cardiologie et de Pneumologie de QuébecUniversité Laval, Québec, Québec, Canada G1V 4G5
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35
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Bérubé JC, Bossé Y. Future clinical implications emerging from recent genome-wide expression studies in asthma. Expert Rev Clin Immunol 2014; 10:985-1004. [PMID: 25001610 DOI: 10.1586/1744666x.2014.932249] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Host susceptibility to environmental triggers is the most likely explanation for the development of asthma. Quantifying gene expression levels in disease-relevant tissues and cell types using fast evolving genomic technologies have generated new hypotheses about the pathogenesis of asthma and identified new therapeutic targets to treat asthma and asthma-exacerbations. New biomarkers and distinct transcriptomic phenotypes in blood, sputum and other tissues were also identified and proved effective to refine asthma classification and guide targeted therapies. The wealth of information provided by transcriptomic studies in asthma is yet to be fully exploited, but discoveries in this field may soon be implemented in clinical settings to improve diagnosis and treatment of patients afflicted with this common disease.
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Affiliation(s)
- Jean-Christophe Bérubé
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Pavillon Marguerite-d'Youville, Y4190, 2725 Chemin Ste-Foy, Quebec, Canada, G1V 4G5
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36
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Winkler T, Venegas JG, Harris RS. MATHEMATICAL MODELING OF VENTILATION DEFECTS IN ASTHMA. DRUG DISCOVERY TODAY. DISEASE MODELS 2014; 15:3-8. [PMID: 26744595 PMCID: PMC4698910 DOI: 10.1016/j.ddmod.2014.02.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Airway narrowing by smooth muscle constriction is a hallmark of asthma attacks that may cause severe difficulties of breathing. However, the causes of asthma and the underlying mechanisms are not fully understood. Bronchoconstriction within a bronchial tree involves complex interactions among the airways that lead to the emergence of regions of poor ventilation (ventilation defects, VDefs) in the lungs. The emphasis of this review is on mathematical modeling of the mechanisms involved in bronchoconstriction and the emergence of the complex airway behavior that leads to VDefs. Additionally, the review discusses characteristic model behaviors and experimental data to demonstrate advances and limitations of different models.
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Affiliation(s)
- Tilo Winkler
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Jose G. Venegas
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - R. Scott Harris
- Department of Medicine, Pulmonary and Critical Care Unit, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
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37
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Munkholm M, Mortensen J. Mucociliary clearance: pathophysiological aspects. Clin Physiol Funct Imaging 2013; 34:171-7. [PMID: 24119105 DOI: 10.1111/cpf.12085] [Citation(s) in RCA: 117] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2013] [Accepted: 08/21/2013] [Indexed: 12/17/2022]
Abstract
Mucociliary clearance has long been known to be a significant innate defence mechanism against inhaled microbes and irritants. Important knowledge has been gathered regarding the anatomy and physiology of this system, and in recent years, extensive studies of the pathophysiology related to lung diseases characterized by defective mucus clearance have resulted in a variety of therapies, which might be able to enhance clearance from the lungs. In addition, ways to study in vivo mucociliary clearance in humans have been developed. This can be used as a means to assess the effect of different pharmacological interventions on clearance rate, to study the importance of defective mucus clearance in different lung diseases or as a diagnostic tool in the work-up of patients with recurrent airway diseases. The aim of this review is to provide an overview of the anatomy, physiology, pathophysiology, and clinical aspects of mucociliary clearance and to present a clinically applicable test that can be used for in vivo assessment of mucociliary clearance in patients. In addition, the reader will be presented with a protocol for this test, which has been validated and used as a diagnostic routine tool in the work-up of patients suspected for primary ciliary dyskinesia at Rigshospitalet, Denmark for over a decade.
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Affiliation(s)
- Mathias Munkholm
- Department of Clinical Physiology, Nuclear Medicine & PET, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark
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38
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Lee-Gosselin A, Pascoe CD, Couture C, Paré PD, Bossé Y. Does the length dependency of airway smooth muscle force contribute to airway hyperresponsiveness? J Appl Physiol (1985) 2013; 115:1304-15. [PMID: 23970527 DOI: 10.1152/japplphysiol.01480.2012] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Airway wall remodeling and lung hyperinflation are two typical features of asthma that may alter the contractility of airway smooth muscle (ASM) by affecting its operating length. The aims of this study were as follows: 1) to describe in detail the "length dependency of ASM force" in response to different spasmogens; and 2) to predict, based on morphological data and a computational model, the consequence of this length dependency of ASM force on airway responsiveness in asthmatic subjects who have both remodeled airway walls and hyperinflated lungs. Ovine tracheal ASM strips and human bronchial rings were isolated and stimulated to contract in response to increasing concentrations of spasmogens at three different lengths. Ovine tracheal strips were more sensitive and generated greater force at longer lengths in response to acetylcholine (ACh) and K(+). Equipotent concentrations of ACh were approximately a log less for ASM stretched by 30% and approximately a log more for ASM shortened by 30%. Similar results were observed in human bronchi in response to methacholine. Morphometric and computational analyses predicted that the ASM of asthmatic subjects may be elongated by 6.6-10.4% (depending on airway generation) due to remodeling and/or hyperinflation, which could increase ACh-induced force by 1.8-117.8% (depending on ASM length and ACh concentration) and enhance the increased resistance to airflow by 0.4-4,432.8%. In conclusion, elongation of ASM imposed by airway wall remodeling and/or hyperinflation may allow ASM to operate at a longer length and to consequently generate more force and respond to lower concentration of spasmogens. This phenomenon could contribute to airway hyperresponsiveness.
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Affiliation(s)
- Audrey Lee-Gosselin
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Department of Medicine, Université Laval, Québec City, Québec, Canada
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39
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Paré PD, Mitzner W. Counterpoint: alterations in airway smooth muscle phenotype do not cause airway hyperresponsiveness in asthma. J Appl Physiol (1985) 2013; 113:839-42. [PMID: 22942220 DOI: 10.1152/japplphysiol.00483.2012a] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Affiliation(s)
- Peter D Paré
- Department of Laboratory Medicine and Pathology University of British Columbia
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40
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Bossé Y. Asthmatic airway hyperresponsiveness: the ants in the tree. Trends Mol Med 2012; 18:627-33. [PMID: 23062358 DOI: 10.1016/j.molmed.2012.09.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2012] [Revised: 08/28/2012] [Accepted: 09/10/2012] [Indexed: 01/27/2023]
Abstract
Airways from asthmatics have a propensity to narrow excessively in response to spasmogens (i.e., contractile agonists), a feature called airway hyperresponsiveness (AHR). AHR is an important contributor to asthma symptoms because the degree of responsiveness dictates the amount of airway narrowing that occurs in response to inflammation-derived spasmogens produced endogenously following exposure to environmental triggers, such as allergens, viruses, or pollutants. The smooth muscle encircling the airways is responsible for responsiveness because it constricts the airway lumen when commanded to contract by spasmogens. However, whether AHR seen in asthmatics is due to stronger muscle is equivocal. In this opinion article, I propose that environmental triggers and other inflammatory molecules released during asthma attacks contribute to AHR by increasing muscle force.
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Affiliation(s)
- Ynuk Bossé
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, QC, G1V 4G5, Canada.
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41
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West AR, Syyong HT, Siddiqui S, Pascoe CD, Murphy TM, Maarsingh H, Deng L, Maksym GN, Bossé Y. Airway contractility and remodeling: links to asthma symptoms. Pulm Pharmacol Ther 2012; 26:3-12. [PMID: 22989721 DOI: 10.1016/j.pupt.2012.08.009] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/19/2012] [Revised: 08/14/2012] [Accepted: 08/16/2012] [Indexed: 02/07/2023]
Abstract
Respiratory symptoms are largely caused by obstruction of the airways. In asthma, airway narrowing mediated by airway smooth muscle (ASM) contraction contributes significantly to obstruction. The spasmogens produced following exposure to environmental triggers, such as viruses or allergens, are initially responsible for ASM activation. However, the extent of narrowing of the airway lumen due to ASM shortening can be influenced by many factors and it remains a real challenge to decipher the exact role of ASM in causing asthmatic symptoms. Innovative tools, such as the forced oscillation technique, continue to develop and have been proven useful to assess some features of ASM function in vivo. Despite these technologic advances, it is still not clear whether excessive narrowing in asthma is driven by ASM abnormalities, by other alterations in non-muscle factors or simply because of the overexpression of spasmogens. This is because a multitude of forces are acting on the airway wall, and because not only are these forces constantly changing but they are also intricately interconnected. To counteract these limitations, investigators have utilized in vitro and ex vivo systems to assess and compare asthmatic and non-asthmatic ASM contractility. This review describes: 1- some muscle and non-muscle factors that are altered in asthma that may lead to airway narrowing and asthma symptoms; 2- some technologies such as the forced oscillation technique that have the potential to unveil the role of ASM in airway narrowing in vivo; and 3- some data from ex vivo and in vitro methods that probe the possibility that airway hyperresponsiveness is due to the altered environment surrounding the ASM or, alternatively, to a hypercontractile ASM phenotype that can be either innate or acquired.
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Affiliation(s)
- Adrian R West
- School of Biomedical Engineering, Dalhousie University, Nova Scotia, Canada
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The pivotal role of airway smooth muscle in asthma pathophysiology. J Allergy (Cairo) 2011; 2011:742710. [PMID: 22220184 PMCID: PMC3246780 DOI: 10.1155/2011/742710] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2011] [Accepted: 08/30/2011] [Indexed: 12/13/2022] Open
Abstract
Asthma is characterized by the association of airway hyperresponsiveness (AHR), inflammation, and remodelling. The aim of the present article is to review the pivotal role of airway smooth muscle (ASM) in the pathophysiology of asthma. ASM is the main effector of AHR. The mechanisms of AHR in asthma may involve a larger release of contractile mediators and/or a lower release of relaxant mediators, an improved ASM cell excitation/contraction coupling, and/or an alteration in the contraction/load coupling. Beyond its contractile function, ASM is also involved in bronchial inflammation and remodelling. Whereas ASM is a target of the inflammatory process, it can also display proinflammatory and immunomodulatory functions, through its synthetic properties and the expression of a wide range of cell surface molecules. ASM remodelling represents a key feature of asthmatic bronchial remodelling. ASM also plays a role in promoting complementary airway structural alterations, in particular by its synthetic function.
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Effect of positive end-expiratory pressure on regional ventilation distribution during bronchoconstriction in rabbit studied by synchrotron radiation imaging. Crit Care Med 2011; 39:1731-8. [PMID: 21494104 DOI: 10.1097/ccm.0b013e318218a375] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To assess the effects of positive end-expiratory pressure on regional ventilation distribution in normal lung and after histamine-induced bronchoconstriction. DESIGN Experimental study. SETTING International research laboratory. SUBJECTS Six healthy New Zealand rabbits weighing 2.5 ± 0.1 kg. INTERVENTIONS Rabbits were anesthetized, tracheostomized, paralyzed, and mechanically ventilated. Synchrotron radiation computed tomography images of tissue density and specific ventilation were acquired using K-edge subtraction imaging with inhaled stable xenon gas in middle and caudal thoracic levels on 0 and 5 cm H(2)O positive end-expiratory pressure at baseline and twice after histamine inhalation. MEASUREMENTS AND MAIN RESULTS At baseline, a positive end-expiratory pressure of 5 cm H(2)O significantly increased lung volume. Histamine inhalation caused patchy areas of decreased specific ventilation, including some areas with no ventilation. After histamine, positive end-expiratory pressure significantly increased the area of well-ventilated lung regions and decreased the heterogeneity of specific ventilation. This improvement went together with a significant but limited increase in the area of hyperinflated lung zones. CONCLUSIONS The findings of this study suggest that in mechanically ventilated rabbit with severely heterogeneous bronchoconstriction, a positive end-expiratory pressure of 5 cm H(2)O significantly improves regional ventilation homogeneity through dilation of flow-limited airways and recruitment of closed airways.
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A 'Good' muscle in a 'Bad' environment: the importance of airway smooth muscle force adaptation to airway hyperresponsiveness. Respir Physiol Neurobiol 2011; 179:269-75. [PMID: 21939788 DOI: 10.1016/j.resp.2011.09.003] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2011] [Revised: 08/17/2011] [Accepted: 09/06/2011] [Indexed: 12/31/2022]
Abstract
Asthma is characterized by airway inflammation, with a consequent increase in spasmogens, and exaggerated airway narrowing in response to stimuli, termed airway hyperresponsiveness (AHR). The nature of any relationship between inflammation and AHR is less clear. Recent ex vivo data has suggested a novel mechanism by which inflammation may lead to AHR, in which increased basal ASM-tone, due to the presence of spasmogens in the airways, may "strengthen" the ASM and ultimately lead to exaggerated airway narrowing. This phenomenon was termed "force adaptation" [Bossé, Y., Chin, L.Y., Paré, P.D., Seow, C.Y., 2009. Adaptation of airway smooth muscle to basal tone: relevance to airway hyperresponsiveness. Am. J. Respir. Cell Mol. Biol. 40, 13-18]. However, it is unknown whether the magnitude of the effect of force adaptation ex vivo could contribute to exaggerated airway narrowing in vivo. Our aim was to utilize a computational model of ASM shortening in order to quantify the potential effect of force adaptation on airway narrowing when all other mechanical factors were kept constant. The shortening in the model is dictated by a balance between physiological loads and ASM force-generating capacity at different lengths. The results suggest that the magnitude of the effect of force adaptation on ASM shortening would lead to substantially more airway narrowing during bronchial challenge at any given airway generation. We speculate that the increased basal ASM-tone in asthma, due to the presence of inflammation-derived spasmogens, produces an increase in the force-generating capacity of ASM, predisposing to AHR during subsequent challenge.
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Paré PD. Central airway compliance in asthma: up or down? Good or bad? Am J Respir Crit Care Med 2011; 183:563-4. [PMID: 21471052 DOI: 10.1164/rccm.201009-1533ed] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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Winkler T, Venegas JG. Self-organized patterns of airway narrowing. J Appl Physiol (1985) 2011; 110:1482-6. [PMID: 21252219 DOI: 10.1152/japplphysiol.01163.2010] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
The behavior of respiratory diseases such as asthma and COPD may involve complicated interactions among multiple factors. Theoretical and experimental data suggest that interdependence among the airways of the bronchial tree leads to the emergence of self-organized patterns of airway narrowing, ventilation defects, and other phenomena when a tipping point is passed. Additionally, evidence from several studies shows that the behavior of an isolated airway is different from an identical airway embedded in the bronchial tree so that experimental results of isolated elements such as airways, airway smooth muscle, or inflammatory pathways may not explain the whole organ behavior. However, there may be factors in the isolated elements that can dramatically change the complex system's behavior. More effective strategies for prevention or recovery from a disease, such as asthma, will depend on our progress in identifying and understanding the essential parts of the self-organized behavior that is involved.
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Affiliation(s)
- Tilo Winkler
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA.
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Abstract
Structure-function relationships in the respiratory system are often a result of the emergence of self-organized patterns or behaviors that are characteristic of certain respiratory diseases. Proper description of such self-organized behavior requires network models that include nonlinear interactions among different parts of the system. This review focuses on 2 models that exhibit self-organized behavior: a network model of the lung parenchyma during the progression of emphysema that is driven by mechanical force-induced breakdown, and an integrative model of bronchoconstriction in asthma that describes interactions among airways within the bronchial tree. Both models suggest that the transition from normal to pathologic states is a nonlinear process that includes a tipping point beyond which interactions among the system components are reinforced by positive feedback, further promoting the progression of pathologic changes. In emphysema, the progressive destruction of tissue is irreversible, while in asthma, it is possible to recover from a severe bronchoconstriction. These concepts may have implications for pulmonary medicine. Specifically, we suggest that structure-function relationships emerging from network behavior across multiple scales should be taken into account when the efficacy of novel treatments or drug therapy is evaluated. Multiscale, computational, network models will play a major role in this endeavor.
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Affiliation(s)
- Tilo Winkler
- Massachusetts General Hospital and Harvard Medical School, Department of Anesthesia, Critical Care and Pain Medicine, Boston, Massachusetts, USA.
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Affiliation(s)
- John V Fahy
- Cardiovascular Research Institute and Department of Medicine, University of California, San Francisco, USA
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