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Jude JA, Panettieri RA. Bronchomotor tone imbalance evokes airway hyperresponsiveness. Expert Rev Respir Med 2024:1-7. [PMID: 39435484 DOI: 10.1080/17476348.2024.2419543] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2024] [Revised: 10/02/2024] [Accepted: 10/17/2024] [Indexed: 10/23/2024]
Abstract
INTRODUCTION Obstructive airway diseases asthma and COPD represent a significant healthcare burden. Airway hyperresponsiveness (AHR), a salient feature of these two diseases, remains the main therapeutic target. Airway smooth muscle (ASM) cell is pivotal for bronchomotor tone and development of AHR in airway diseases. The contractile and relaxation processes in ASM cells maintain a homeostatic bronchomotor tone. It is critical to understand the molecular mechanisms that disrupt the homeostasis to identify novel therapeutic strategies for AHR. AREAS COVERED Based on review of literature and published findings from our laboratory, we describe intrinsic and extrinsic factors - disease phenotype, toxicants, inflammatory/remodeling mediators- that amplify excitation-contraction (E-C) coupling and ASM shortening and or diminish relaxation to alter bronchomotor homeostasis. We posit that an understanding of the ASM mechanisms involved in bronchomotor tone imbalance will provide platforms to develop novel therapeutic approaches to treat AHR in asthma and COPD. EXPERT OPINION Contractile and relaxation processes in ASM cell are modulated by intrinsic and extrinsic factors to elicit bronchomotor tone imbalance. Innovative experimental approaches will serve as essential tools for elucidating the imbalance mechanisms and to identify novel therapeutic targets for AHR.
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Affiliation(s)
- Joseph A Jude
- Rutgers Institute for Translational Medicine and Science, Child Health Institute of New Jersey, Rutgers, The State University of New Jersey, New Brunswick, NJ, USA
| | - Reynold A Panettieri
- Rutgers Institute for Translational Medicine and Science, Child Health Institute of New Jersey, Rutgers, The State University of New Jersey, New Brunswick, NJ, USA
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2
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Boucher M, Henry C, Gélinas L, Packwood R, Rojas-Ruiz A, Fereydoonzad L, Graham P, Bossé Y. High throughput screening of airway constriction in mouse lung slices. Sci Rep 2024; 14:20133. [PMID: 39210022 PMCID: PMC11362152 DOI: 10.1038/s41598-024-71170-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2024] [Accepted: 08/26/2024] [Indexed: 09/04/2024] Open
Abstract
The level of airway constriction in thin slices of lung tissue is highly variable. Owing to the labor-intensive nature of these experiments, determining the number of airways to be analyzed in order to allocate a reliable value of constriction in one mouse is challenging. Herein, a new automated device for physiology and image analysis was used to facilitate high throughput screening of airway constriction in lung slices. Airway constriction was first quantified in slices of lungs from male BALB/c mice with and without experimental asthma that were inflated with agarose through the trachea or trans-parenchymal injections. Random sampling simulations were then conducted to determine the number of airways required per mouse to quantify maximal constriction. The constriction of 45 ± 12 airways per mouse in 32 mice were analyzed. Mean maximal constriction was 37.4 ± 32.0%. The agarose inflating technique did not affect the methacholine response. However, the methacholine constriction was affected by experimental asthma (p = 0.003), shifting the methacholine concentration-response curve to the right, indicating a decreased sensitivity. Simulations then predicted that approximately 35, 16 and 29 airways per mouse are needed to quantify the maximal constriction mean, standard deviation and coefficient of variation, respectively; these numbers varying between mice and with experimental asthma.
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Affiliation(s)
- Magali Boucher
- Institut Universitaire de Cardiologie et de Pneumologie de Québec (IUCPQ)-Université Laval, Pavillon M, room 2687, 2725, chemin Sainte-Foy, Quebec, Qc, G1V 4G5, Canada
| | - Cyndi Henry
- Institut Universitaire de Cardiologie et de Pneumologie de Québec (IUCPQ)-Université Laval, Pavillon M, room 2687, 2725, chemin Sainte-Foy, Quebec, Qc, G1V 4G5, Canada
| | - Louis Gélinas
- Institut Universitaire de Cardiologie et de Pneumologie de Québec (IUCPQ)-Université Laval, Pavillon M, room 2687, 2725, chemin Sainte-Foy, Quebec, Qc, G1V 4G5, Canada
| | - Rosalie Packwood
- Institut Universitaire de Cardiologie et de Pneumologie de Québec (IUCPQ)-Université Laval, Pavillon M, room 2687, 2725, chemin Sainte-Foy, Quebec, Qc, G1V 4G5, Canada
| | - Andrés Rojas-Ruiz
- Institut Universitaire de Cardiologie et de Pneumologie de Québec (IUCPQ)-Université Laval, Pavillon M, room 2687, 2725, chemin Sainte-Foy, Quebec, Qc, G1V 4G5, Canada
| | | | | | - Ynuk Bossé
- Institut Universitaire de Cardiologie et de Pneumologie de Québec (IUCPQ)-Université Laval, Pavillon M, room 2687, 2725, chemin Sainte-Foy, Quebec, Qc, G1V 4G5, Canada.
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3
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Gélinas L, Rojas-Ruiz A, Boucher M, Henry C, Bossé Y. Sensitivity of the airway smooth muscle in terms of force, shortening and stiffness. Respir Physiol Neurobiol 2024; 325:104264. [PMID: 38599345 DOI: 10.1016/j.resp.2024.104264] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2024] [Revised: 04/02/2024] [Accepted: 04/06/2024] [Indexed: 04/12/2024]
Abstract
Eight pig tracheal strips were stimulated to contract with log increments of methacholine from 10-8 to 10-5 M. For each strip, the concentration-response was repeated four times in a randomized order to measure isometric force, isotonic shortening against a load corresponding to either 5 or 10 % of a reference force, and average force, stiffness, elastance and resistance over one cycle while the strip length was oscillating sinusoidally by 5 % at 0.2 Hz. For each readout, the logEC50 was calculated and compared. Isotonic shortening with a 5 % load had the lowest logEC50 (-7.13), yielding a greater sensitivity than any other contractile readout (p<0.05). It was followed by isotonic shortening with a 10 % load (-6.66), elastance (-6.46), stiffness (-6.46), resistance (-6.38), isometric force (-6.32), and average force (-6.30). Some of these differences were significant. For example, the EC50 with the average force was 44 % greater than with the elastance (p=0.001). The methacholine sensitivity is thus affected by the contractile readout being measured.
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Affiliation(s)
- Louis Gélinas
- Institut Universitaire de Cardiologie et de Pneumologie de Québec (IUCPQ) - Université Laval, Québec, QC, Canada
| | - Andrés Rojas-Ruiz
- Institut Universitaire de Cardiologie et de Pneumologie de Québec (IUCPQ) - Université Laval, Québec, QC, Canada
| | - Magali Boucher
- Institut Universitaire de Cardiologie et de Pneumologie de Québec (IUCPQ) - Université Laval, Québec, QC, Canada
| | - Cyndi Henry
- Institut Universitaire de Cardiologie et de Pneumologie de Québec (IUCPQ) - Université Laval, Québec, QC, Canada
| | - Ynuk Bossé
- Institut Universitaire de Cardiologie et de Pneumologie de Québec (IUCPQ) - Université Laval, Québec, QC, Canada.
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Yasuda Y, Wang L, Chitano P, Seow CY. Critical roles of airway smooth muscle in mediating deep-inspiration-induced bronchodilation: a big stretch? Respir Res 2023; 24:250. [PMID: 37853472 PMCID: PMC10585885 DOI: 10.1186/s12931-023-02538-8] [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: 08/15/2023] [Accepted: 09/14/2023] [Indexed: 10/20/2023] Open
Abstract
BACKGROUND Deep inspiration (DI) has been shown to induce bronchodilation and bronchoprotection in bronchochallenged healthy subjects, but not in asthmatics. Strain-induced relaxation of airway smooth muscle (ASM) is considered one of the factors responsible for these effects. Other factors include the release or redistribution of pulmonary surfactant, alteration in mucus plugs, and changes in airway heterogeneity. MAIN BODY The present review is focused on the DI effect on ASM function, based on recent findings from ex vivo sheep lung experiments showing a large change in airway diameter during a DI. The amount of stretch on the airways, when applied to isolated airway rings in vitro, caused a substantial decrease in ASM contractility that takes many minutes to recover. When challenged with a bronchoconstrictor, the increase in pulmonary resistance in the ex vivo ovine lungs is mostly due to the increase in airway resistance. CONCLUSIONS Although non-ASM related factors cannot be excluded, the large strain on the airways associated with a DI substantially reduces ASM contractility and thus can account for most of the bronchodilatory and bronchoprotective effects of DI.
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Affiliation(s)
- Yuto Yasuda
- Centre for Heart Lung Innovation, St. Paul's Hospital, Providence Health Care, University of British Columbia, 1081 Burrard Street, Vancouver, BC, V6Z 1Y6, Canada.
| | - Lu Wang
- Centre for Heart Lung Innovation, St. Paul's Hospital, Providence Health Care, University of British Columbia, 1081 Burrard Street, Vancouver, BC, V6Z 1Y6, Canada
| | - Pasquale Chitano
- Centre for Heart Lung Innovation, St. Paul's Hospital, Providence Health Care, University of British Columbia, 1081 Burrard Street, Vancouver, BC, V6Z 1Y6, Canada
| | - Chun Y Seow
- Centre for Heart Lung Innovation, St. Paul's Hospital, Providence Health Care, University of British Columbia, 1081 Burrard Street, Vancouver, BC, V6Z 1Y6, Canada
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada
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5
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Ijpma G, Lauzon AM. Automated, high temporal resolution mechanics measurements during incubation of contractile tissues. J Biomech 2023; 152:111577. [PMID: 37058766 DOI: 10.1016/j.jbiomech.2023.111577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Revised: 03/23/2023] [Accepted: 04/03/2023] [Indexed: 04/08/2023]
Abstract
Muscle tissue mechanics and contractility measurements have a great advantage over cultured cell level experiments as their mechanical and contractile properties are much closer to in vivo tissue properties. However, tissue level experiments cannot be combined with incubation with the same time resolution and consistency as cell culture studies. Here we present a system in which contractile tissues can be incubated for days while intermittently being tested for their mechanical and contractile properties. A two-chamber system was developed with control of temperature in the outer chamber and CO2 and humidity control in the inner, sterile chamber. Incubation medium, to which biologically active components may be added, is reused after each mechanics test to preserve both added and released components. Mechanics and contractility are measured in a different medium to which, through a high accuracy syringe pump, up to 6 different agonists in a 100-fold dose range can be added. The whole system can be operated through fully automated protocols from a personal computer. Testing data shows accurate maintenance of temperature, CO2 and relative humidity at pre-set levels. Equine trachealis smooth muscle tissues tested in the system showed no signs of infection after 72 h with incubation medium replacement every 24 h. Methacholine dosing and electrical field stimulation every 4 h showed consistent responses. In conclusion, the developed system is a great improvement on the manual incubation techniques being used thus far, improving on time resolution, repeatability and robustness, while reducing contamination risk and tissue damage from repeated handling.
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Xiong D(JP, Martin JG, Lauzon AM. Airway smooth muscle function in asthma. Front Physiol 2022; 13:993406. [PMID: 36277199 PMCID: PMC9581182 DOI: 10.3389/fphys.2022.993406] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Accepted: 09/14/2022] [Indexed: 11/27/2022] Open
Abstract
Known to have affected around 340 million people across the world in 2018, asthma is a prevalent chronic inflammatory disease of the airways. The symptoms such as wheezing, dyspnea, chest tightness, and cough reflect episodes of reversible airway obstruction. Asthma is a heterogeneous disease that varies in clinical presentation, severity, and pathobiology, but consistently features airway hyperresponsiveness (AHR)—excessive airway narrowing due to an exaggerated response of the airways to various stimuli. Airway smooth muscle (ASM) is the major effector of exaggerated airway narrowing and AHR and many factors may contribute to its altered function in asthma. These include genetic predispositions, early life exposure to viruses, pollutants and allergens that lead to chronic exposure to inflammatory cells and mediators, altered innervation, airway structural cell remodeling, and airway mechanical stress. Early studies aiming to address the dysfunctional nature of ASM in the etiology and pathogenesis of asthma have been inconclusive due to the methodological limitations in assessing the intrapulmonary airways, the site of asthma. The study of the trachealis, although convenient, has been misleading as it has shown no alterations in asthma and it is not as exposed to inflammatory cells as intrapulmonary ASM. Furthermore, the cartilage rings offer protection against stress and strain of repeated contractions. More recent strategies that allow for the isolation of viable intrapulmonary ASM tissue reveal significant mechanical differences between asthmatic and non-asthmatic tissues. This review will thus summarize the latest techniques used to study ASM mechanics within its environment and in isolation, identify the potential causes of the discrepancy between the ASM of the extra- and intrapulmonary airways, and address future directions that may lead to an improved understanding of ASM hypercontractility in asthma.
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Affiliation(s)
- Dora (Jun Ping) Xiong
- Meakins-Christie Laboratories, Research Institute of the McGill University Health Centre, Montreal, QC, Canada
- Department of Medicine, McGill University, Montreal, QC, Canada
| | - James G. Martin
- Meakins-Christie Laboratories, Research Institute of the McGill University Health Centre, Montreal, QC, Canada
- Department of Medicine, McGill University, Montreal, QC, Canada
| | - Anne-Marie Lauzon
- Meakins-Christie Laboratories, Research Institute of the McGill University Health Centre, Montreal, QC, Canada
- Department of Medicine, McGill University, Montreal, QC, Canada
- *Correspondence: Anne-Marie Lauzon,
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7
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Riccardi D, Ward JPT, Yarova PL, Janssen LJ, Lee TH, Ying S, Corrigan CJ. Topical therapy with negative allosteric modulators of the calcium-sensing receptor (calcilytics) for the management of asthma: the beginning of a new era? Eur Respir J 2022; 60:13993003.02103-2021. [DOI: 10.1183/13993003.02103-2021] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Accepted: 12/16/2021] [Indexed: 11/05/2022]
Abstract
In this review article we present the evidence to date supporting the role of the calcium-sensing receptor (CaSR) as a key, pluripotential molecular trigger for asthma and speculate on the likely benefits of topical therapy of asthma with negative allosteric modulators of the CaSR: calcilytics.
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8
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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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9
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Camoretti-Mercado B, Lockey RF. Airway smooth muscle pathophysiology in asthma. J Allergy Clin Immunol 2021; 147:1983-1995. [PMID: 34092351 DOI: 10.1016/j.jaci.2021.03.035] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Revised: 03/06/2021] [Accepted: 03/16/2021] [Indexed: 02/08/2023]
Abstract
The airway smooth muscle (ASM) cell plays a central role in the pathogenesis of asthma and constitutes an important target for treatment. These cells control muscle tone and thus regulate the opening of the airway lumen and air passage. Evidence indicates that ASM cells participate in the airway hyperresponsiveness as well as the inflammatory and remodeling processes observed in asthmatic subjects. Therapeutic approaches require a comprehensive understanding of the structure and function of the ASM in both the normal and disease states. This review updates current knowledge about ASM and its effects on airway narrowing, remodeling, and inflammation in asthma.
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Affiliation(s)
- Blanca Camoretti-Mercado
- Division of Allergy and Immunology, Department of Internal Medicine, Morsani College of Medicine, University of South Florida, Tampa, Fla.
| | - Richard F Lockey
- Division of Allergy and Immunology, Department of Internal Medicine, Morsani College of Medicine, University of South Florida, Tampa, Fla
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10
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van den Bosch WB, James AL, Tiddens HA. Structure and function of small airways in asthma patients revisited. Eur Respir Rev 2021; 30:200186. [PMID: 33472958 PMCID: PMC9488985 DOI: 10.1183/16000617.0186-2020] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Accepted: 08/27/2020] [Indexed: 12/21/2022] Open
Abstract
Small airways (<2 mm in diameter) are probably involved across almost all asthma severities and they show proportionally more structural and functional abnormalities with increasing asthma severity. The structural and functional alterations of the epithelium, extracellular matrix and airway smooth muscle in small airways of people with asthma have been described over many years using in vitro studies, animal models or imaging and modelling methods. The purpose of this review was to provide an overview of these observations and to outline several potential pathophysiological mechanisms regarding the role of small airways in asthma.
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Affiliation(s)
- Wytse B. van den Bosch
- Dept of Paediatric Pulmonology and Allergology, Erasmus MC – Sophia Children’s Hospital, University Medical Center Rotterdam, Rotterdam, The Netherlands
- Dept of Radiology and Nuclear Medicine, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
| | - Alan L. James
- Dept of Pulmonary Physiology and Sleep Medicine, Sir Charles Gairdner Hospital, Perth, Australia
| | - Harm A.W.M. Tiddens
- Dept of Paediatric Pulmonology and Allergology, Erasmus MC – Sophia Children’s Hospital, University Medical Center Rotterdam, Rotterdam, The Netherlands
- Dept of Radiology and Nuclear Medicine, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
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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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12
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Ijpma G, Kachmar L, Panariti A, Matusovsky OS, Torgerson D, Benedetti A, Lauzon AM. Intrapulmonary airway smooth muscle is hyperreactive with a distinct proteome in asthma. Eur Respir J 2020; 56:13993003.02178-2019. [PMID: 32299863 DOI: 10.1183/13993003.02178-2019] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Accepted: 03/05/2020] [Indexed: 11/05/2022]
Abstract
Constriction of airways during asthmatic exacerbation is the result of airway smooth muscle (ASM) contraction. Although it is generally accepted that ASM is hypercontractile in asthma, this has not been unambiguously demonstrated. Whether airway hyperresponsiveness (AHR) is the result of increased ASM mass alone or also increased contractile force generation per unit of muscle directly determines the potential avenues for treatment.To assess whether ASM is hypercontractile we performed a series of mechanics measurements on isolated ASM from intrapulmonary airways and trachealis from human lungs. We analysed the ASM and whole airway proteomes to verify if proteomic shifts contribute to changes in ASM properties.We report an increase in isolated ASM contractile stress and stiffness specific to asthmatic human intrapulmonary bronchi, the site of increased airway resistance in asthma. Other contractile parameters were not altered. Principal component analysis (PCA) of unbiased mass spectrometry data showed clear clustering of asthmatic subjects with respect to ASM specific proteins. The whole airway proteome showed upregulation of structural proteins. We did not find any evidence for a difference in the regulation of myosin activity in the asthmatic ASM.In conclusion, we showed that ASM is indeed hyperreactive at the level of intrapulmonary airways in asthma. We identified several proteins that are upregulated in asthma that could contribute to hyperreactivity. Our data also suggest enhanced force transmission associated with enrichment of structural proteins in the whole airway. These findings may lead to novel directions for treatment development in asthma.
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Affiliation(s)
- Gijs Ijpma
- Dept of Medicine, McGill University, Montreal, QC, Canada.,Meakins-Christie Laboratories, Research Institute of the McGill University Health Centre, Montreal, QC, Canada
| | - Linda Kachmar
- Dept of Medicine, McGill University, Montreal, QC, Canada.,Meakins-Christie Laboratories, Research Institute of the McGill University Health Centre, Montreal, QC, Canada
| | - Alice Panariti
- Dept of Medicine, McGill University, Montreal, QC, Canada.,Meakins-Christie Laboratories, Research Institute of the McGill University Health Centre, Montreal, QC, Canada
| | - Oleg S Matusovsky
- Dept of Kinesiology and Physical Education, McGill University, Montreal, QC, Canada
| | - Dara Torgerson
- Meakins-Christie Laboratories, Research Institute of the McGill University Health Centre, Montreal, QC, Canada.,McGill University and Génome Québec Innovation Centre, Montreal, QC, Canada
| | - Andrea Benedetti
- Dept of Medicine, McGill University, Montreal, QC, Canada.,Dept of Epidemiology, Biostatistics and Occupational Health, McGill University, Montreal, QC, Canada.,Respiratory Epidemiology and Clinical Research Unit, McGill University Health Centre, Montreal, QC, Canada
| | - Anne-Marie Lauzon
- Dept of Medicine, McGill University, Montreal, QC, Canada .,Meakins-Christie Laboratories, Research Institute of the McGill University Health Centre, Montreal, QC, Canada
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13
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Donovan GM, Langton D, Noble PB. Phenotype- and patient-specific modelling in asthma: Bronchial thermoplasty and uncertainty quantification. J Theor Biol 2020; 501:110337. [PMID: 32511977 DOI: 10.1016/j.jtbi.2020.110337] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Revised: 05/14/2020] [Accepted: 05/18/2020] [Indexed: 11/29/2022]
Abstract
Theoretical models can help to overcome experimental limitations to better our understanding of lung physiology and disease. While such efforts often begin in broad terms by determining the effect of a disease process on a relevant biological output, more narrowly defined simulations may inform clinical practice. Two such examples are phenotype-specific and patient-specific models, the former being specific to a group of patients with common characteristics, and the latter to an individual patient, in view of likely differences (heterogeneity) between patients. However, in order for such models to be useful, they must be sufficiently accurate, given the available data about the specific characteristics of the patient. We show that, for asthma in particular, this approach is promising: phenotype-specific targeting may be an effective way of selecting patients for treatment based on their airway remodelling phenotype, and patient-specific targeting may be viable with the use of a clinically-plausible dataset. Specifically we consider asthma and its treatment by bronchial thermoplasty, in which the airway smooth muscle layer is directly targeted by thermal energy. Patient-specific and phenotype-specific models in this context are considered using a combination of biobank data from ex vivo tissue samples, CT imaging, and optical coherence tomography which allows more detailed resolution of the airway wall structures.
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Affiliation(s)
- Graham M Donovan
- Department of Mathematics, University of Auckland, Auckland 1142, New Zealand.
| | - David Langton
- Department of Thoracic Medicine, Frankston Hospital, Peninsula Health, 2 Hastings Road, Frankston, VIC 3199, Australia; Faculty of Medicine, Nursing and Health Sciences, Monash University, Clayton, Vic, Australia
| | - Peter B Noble
- School of Human Sciences, The University of Western Australia, Crawley, Western Australia, Australia
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14
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Anthracopoulos MB, Everard ML. Asthma: A Loss of Post-natal Homeostatic Control of Airways Smooth Muscle With Regression Toward a Pre-natal State. Front Pediatr 2020; 8:95. [PMID: 32373557 PMCID: PMC7176812 DOI: 10.3389/fped.2020.00095] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Accepted: 02/24/2020] [Indexed: 12/20/2022] Open
Abstract
The defining feature of asthma is loss of normal post-natal homeostatic control of airways smooth muscle (ASM). This is the key feature that distinguishes asthma from all other forms of respiratory disease. Failure to focus on impaired ASM homeostasis largely explains our failure to find a cure and contributes to the widespread excessive morbidity associated with the condition despite the presence of effective therapies. The mechanisms responsible for destabilizing the normal tight control of ASM and hence airways caliber in post-natal life are unknown but it is clear that atopic inflammation is neither necessary nor sufficient. Loss of homeostasis results in excessive ASM contraction which, in those with poor control, is manifest by variations in airflow resistance over short periods of time. During viral exacerbations, the ability to respond to bronchodilators is partially or almost completely lost, resulting in ASM being "locked down" in a contracted state. Corticosteroids appear to restore normal or near normal homeostasis in those with poor control and restore bronchodilator responsiveness during exacerbations. The mechanism of action of corticosteroids is unknown and the assumption that their action is solely due to "anti-inflammatory" effects needs to be challenged. ASM, in evolutionary terms, dates to the earliest land dwelling creatures that required muscle to empty primitive lungs. ASM appears very early in embryonic development and active peristalsis is essential for the formation of the lungs. However, in post-natal life its only role appears to be to maintain airways in a configuration that minimizes resistance to airflow and dead space. In health, significant constriction is actively prevented, presumably through classic negative feedback loops. Disruption of this robust homeostatic control can develop at any age and results in asthma. In order to develop a cure, we need to move from our current focus on immunology and inflammatory pathways to work that will lead to an understanding of the mechanisms that contribute to ASM stability in health and how this is disrupted to cause asthma. This requires a radical change in the focus of most of "asthma research."
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Affiliation(s)
| | - Mark L. Everard
- Division of Paediatrics & Child Health, Perth Children's Hospital, University of Western Australia, Perth, WA, Australia
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Cairncross A, Jones RL, Elliot JG, McFawn PK, James AL, Noble PB. Airway narrowing and response to simulated deep inspiration in bronchial segments from subjects with fixed airflow obstruction. J Appl Physiol (1985) 2020; 128:757-767. [PMID: 32105523 DOI: 10.1152/japplphysiol.00439.2019] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The volume fraction of extracellular matrix (ECM) within the layer of airway smooth muscle (ASM) is increased in subjects with fixed airflow obstruction. We postulated that changes in ECM within the ASM layer will impact force transmission during induced contraction and/or in response to externally applied stresses like a deep inspiration (DI). Subjects were patients undergoing lung resection surgery who were categorized as unobstructed (n = 12) or "fixed" obstructed (n = 6) on the basis of preoperative spirometry. The response to a DI, assessed by the ratio of isovolumic flows from maximal and partial inspirations (M/P), was also measured preoperatively. M/P was reduced in the obstructed group (P = 0.02). Postoperatively, bronchial segments were obtained from resected tissue, and luminal narrowing to acetylcholine and bronchodilation to simulated DI were assessed in vitro. Airway wall dimensions and the volume fraction of ECM within the ASM were quantified. Maximal airway narrowing to acetylcholine (P = 0.01) and the volume fraction of ECM within the ASM layer (P = 0.02) were increased in the obstructed group, without a change in ASM thickness. Whereas bronchodilation to simulated DI in vitro was not different between obstructed and unobstructed groups, it was correlated with increased M/P (bronchodilation/less bronchoconstriction) in vivo (P = 0.03). The volume fraction of ECM was inversely related to forced expiratory volume in 1 s FEV1 %predicted (P = 0.04) and M/P (P = 0.01). Results show that in subjects with fixed airflow obstruction the mechanical behavior of the airway wall is altered and there is a contemporaneous shift in the structural composition of the ASM layer.NEW & NOTEWORTHY Cartilaginous airways from subjects with fixed airflow obstruction have an increase in the volume fraction of extracellular matrix within the airway smooth muscle layer. These airways are also intrinsically more reactive to a contractile stimulus, which is expected to contribute to airway hyperresponsiveness in this population, often attributed to geometric mechanisms. In view of these results, we speculate on how changes in extracellular matrix may impact airway mechanics.
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Affiliation(s)
- Alvenia Cairncross
- School of Human Sciences, University of Western Australia, Crawley, Western Australia, Australia
| | - Robyn L Jones
- Department of Pulmonary Physiology and Sleep Medicine, Sir Charles Gairdner Hospital, Nedlands, Western Australia, Australia
| | - John G Elliot
- School of Human Sciences, University of Western Australia, Crawley, Western Australia, Australia.,Department of Pulmonary Physiology and Sleep Medicine, Sir Charles Gairdner Hospital, Nedlands, Western Australia, Australia
| | - Peter K McFawn
- School of Human Sciences, University of Western Australia, Crawley, Western Australia, Australia
| | - Alan L James
- Department of Pulmonary Physiology and Sleep Medicine, Sir Charles Gairdner Hospital, Nedlands, Western Australia, Australia.,School of Medicine and Pharmacology, University of Western Australia, Crawley, Western Australia, Australia
| | - Peter B Noble
- School of Human Sciences, University of Western Australia, Crawley, Western Australia, Australia
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16
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Roos KLT, Al-Jumaily AM. Effects of superimposed pressure oscillations on a chronic sensitized airways mouse model. Am J Physiol Lung Cell Mol Physiol 2020; 318:L900-L907. [PMID: 32101015 DOI: 10.1152/ajplung.00348.2019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The hyperconstriction of airway smooth muscle (ASM) is the main driving mechanism during an asthmatic attack. The airway lumen is reduced, resistance to airflow increases, and normal breathing becomes more difficult. The tissue contraction can be temporarily relieved by using bronchodilator drugs, which induce relaxation of the constricted airways. In vitro studies indicate that relaxation of isolated, precontracted ASM is induced by mechanical oscillations in healthy subjects but not in asthmatic subjects. Further, short-term acute asthmatic subjects respond to superimposed pressure oscillations (SIPO) generated in the range of 5-15 Hz with ~50% relaxation of preconstricted sensitized airways. Mechanical oscillations, and specifically SIPO, are not widely characterized in asthmatic models. The objective of this in vivo study is to determine the effects of a range of oscillation patterns similar to our previous acute study differing from normal breathing. Both healthy and sensitized mice were observed, with their responses to SIPO treatments measured during induced bronchoconstriction resulting from acetylcholine (Ach) challenge. SIPO-generated results were compared with data from treatments using the bronchorelaxant isoproterenol (ISO). The study shows that SIPO in the range of 5-20 Hz induces relaxation in chronic sensitized airways, with significant improvements in respiratory parameters at SIPO values near 1.7 cmH2O irrespective of the frequency of generation.
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Affiliation(s)
- K L T Roos
- Institute of Biomedical Technologies, Auckland University of Technology, Auckland, New Zealand
| | - A M Al-Jumaily
- Institute of Biomedical Technologies, Auckland University of Technology, Auckland, New Zealand
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17
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Gazzola M, Khadangi F, Clisson M, Beaudoin J, Clavel MA, Bossé Y. Airway smooth muscle adapting in dynamic conditions is refractory to the bronchodilator effect of a deep inspiration. Am J Physiol Lung Cell Mol Physiol 2020; 318:L452-L458. [PMID: 31913645 DOI: 10.1152/ajplung.00270.2019] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Airway smooth muscle (ASM) is continuously strained during breathing at tidal volume. Whether this tidal strain influences the magnitude of the bronchodilator response to a deep inspiration (DI) is not clearly defined. The present in vitro study examines the effect of tidal strain on the bronchodilator effect of DIs. ASM strips from sheep tracheas were mounted in organ baths and then subjected to stretches (30% strain), simulating DIs at varying time intervals. In between simulated DIs, the strips were either held at a fixed length (isometric) or oscillated continuously by 6% (length oscillations) to simulate tidal strain. The contractile state of the strips was also controlled by adding either methacholine or isoproterenol to activate or relax ASM, respectively. Although the time-dependent gain in force caused by methacholine was attenuated by length oscillations, part of the acquired force in the oscillating condition was preserved postsimulated DIs, which was not the case in the isometric condition. Consequently, the bronchodilator effect of simulated DIs (i.e., the decline in force postsimulated versus presimulated DIs) was attenuated in oscillating versus isometric conditions. These findings suggest that an ASM operating in a dynamic environment acquired adaptations that make it refractory to the decline in contractility inflicted by a larger strain simulating a DI.
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Affiliation(s)
- Morgan Gazzola
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Laval University, Quebec City, Quebec, Canada
| | - Fatemeh Khadangi
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Laval University, Quebec City, Quebec, Canada
| | - Marine Clisson
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Laval University, Quebec City, Quebec, Canada
| | - Jonathan Beaudoin
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Laval University, Quebec City, Quebec, Canada
| | - Marie-Annick Clavel
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Laval University, Quebec City, Quebec, Canada
| | - Ynuk Bossé
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Laval University, Quebec City, Quebec, Canada
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18
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Gazzola M, Henry C, Lortie K, Khadangi F, Park CY, Fredberg JJ, Bossé Y. Airway smooth muscle tone increases actin filamentogenesis and contractile capacity. Am J Physiol Lung Cell Mol Physiol 2020; 318:L442-L451. [PMID: 31850799 DOI: 10.1152/ajplung.00205.2019] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Force adaptation of airway smooth muscle (ASM) is a process whereby the presence of tone (i.e., a sustained contraction) increases the contractile capacity. For example, tone has been shown to increase airway responsiveness in both healthy mice and humans. The goal of the present study is to elucidate the underlying molecular mechanisms. The maximal force generated by mouse tracheas was measured in response to 10-4 M of methacholine following a 30-min period with or without tone elicited by the EC30 of methacholine. To confirm the occurrence of force adaptation at the cellular level, traction force generated by cultured human ASM cells was also measured following a similar protocol. Different pharmacological inhibitors were used to investigate the role of Rho-associated coiled-coil containing protein kinase (ROCK), protein kinase C (PKC), myosin light chain kinase (MLCK), and actin polymerization in force adaptation. The phosphorylation level of the regulatory light chain (RLC) of myosin, the amount of actin filaments, and the activation level of the actin-severing protein cofilin were also quantified. Although ROCK, PKC, MLCK, and RLC phosphorylation was not implicated, force adaptation was prevented by inhibiting actin polymerization. Interestingly, the presence of tone blocked the activation of cofilin in addition to increasing the amount of actin filaments to a maximal level. We conclude that actin filamentogenesis induced by tone, resulting from both actin polymerization and the prevention of cofilin-mediated actin cleavage, is the main molecular mechanism underlying force adaptation.
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Affiliation(s)
- Morgan Gazzola
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Quebec City, Quebec, Canada
| | - Cyndi Henry
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Quebec City, Quebec, Canada
| | - Katherine Lortie
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Quebec City, Quebec, Canada
| | - Fatemeh Khadangi
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Quebec City, Quebec, Canada
| | - Chan Young Park
- Harvard School of Public Health, Harvard University, Boston, Massachusetts
| | - Jeffrey J Fredberg
- Harvard School of Public Health, Harvard University, Boston, Massachusetts
| | - Ynuk Bossé
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Quebec City, Quebec, Canada
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19
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Matusovsky OS, Kachmar L, Ijpma G, Panariti A, Benedetti A, Martin JG, Lauzon AM. Contractile Properties of Intrapulmonary Airway Smooth Muscle in Cystic Fibrosis. Am J Respir Cell Mol Biol 2019; 60:434-444. [PMID: 30359078 DOI: 10.1165/rcmb.2018-0005oc] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Cystic fibrosis (CF) is an autosomal-recessive disease caused by mutations in the CF transmembrane conductance regulator gene. Many patients with CF have asthma-like symptoms and airway hyperresponsiveness, which are potentially associated with altered airway smooth muscle (ASM) contractility. Our goal in this study was to assess the contractility of the CF intrapulmonary ASM. ASM strips were dissected from human control and CF intrapulmonary airways, and assessed for methacholine-induced shortening velocity, maximal force, and stress. We also assessed isoproterenol responses in maximally methacholine-contracted ASM. ASM strips were then incubated for 16 hours with IL-13 and measurements were repeated. Myosin light chain kinase (MLCK) expression was assessed by Western blotting. Airways were immunostained for morphometry. ASM mass was increased in CF airways, which likely contributes to airway hyperresponsiveness. Although ASM contractile properties were not intrinsically different between patients with CF and control subjects, CF ASM responded differently in the presence of the inflammatory mediator IL-13, showing impairment in β-adrenergic-induced relaxation. Indeed, the percentage of relaxation measured at maximal isoproterenol concentrations in the CF ASM was significantly lower after incubation with IL-13 (46.0% ± 6.7% relaxation) than without IL-13 (74.0% ± 7.7% relaxation, P = 0.018). It was also significantly lower than that observed in control ASM incubated with IL-13 (68.8% ± 4.9% relaxation, P = 0.048) and without IL-13 (82.4% ± 9.9%, P = 0.0035). CF ASM incubated with IL-13 also expressed greater levels of MLCK. Thus, our data suggest that the combination of an increase in ASM mass, increased MLCK expression, and inflammation-induced β-adrenergic hyporesponsiveness may contribute to airway dysfunction in CF.
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Affiliation(s)
- Oleg S Matusovsky
- 1 Meakins-Christie Laboratories, Research Institute of the McGill University Health Center
| | - Linda Kachmar
- 1 Meakins-Christie Laboratories, Research Institute of the McGill University Health Center
| | - Gijs Ijpma
- 1 Meakins-Christie Laboratories, Research Institute of the McGill University Health Center
| | - Alice Panariti
- 1 Meakins-Christie Laboratories, Research Institute of the McGill University Health Center
| | - Andrea Benedetti
- 2 Department of Medicine, and.,3 Department of Epidemiology, Biostatistics and Occupational Health, McGill University, Montréal, Québec, Canada; and.,4 Respiratory Epidemiology and Clinical Research Unit, Montreal Chest Institute, Montréal, Québec, Canada
| | - James G Martin
- 1 Meakins-Christie Laboratories, Research Institute of the McGill University Health Center.,2 Department of Medicine, and
| | - Anne-Marie Lauzon
- 1 Meakins-Christie Laboratories, Research Institute of the McGill University Health Center.,2 Department of Medicine, and
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20
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Jang JH, Panariti A, O’Sullivan MJ, Pyrch M, Wong C, Lauzon AM, Martin JG. Characterization of cystic fibrosis airway smooth muscle cell proliferative and contractile activities. Am J Physiol Lung Cell Mol Physiol 2019; 317:L690-L701. [DOI: 10.1152/ajplung.00090.2019] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Cystic fibrosis (CF) is a genetic disease that causes multiple airway abnormalities. Two major respiratory consequences of CF are airway hyperresponsiveness (AHR) and airway remodeling. Airway smooth muscle (ASM) is hypothesized to be responsible for the airway dysfunction, since their thickening is involved in remodeling, and excessive contraction by the ASM may cause AHR. It is unclear whether the ASM is intrinsically altered to favor increased contractility or proliferation or if microenvironmental influences induce pathological behavior in vivo. In this study, we examined the contractile and proliferative properties of ASM cells isolated from healthy donor and CF transplant lungs. Assays of proliferation showed that CF ASM proliferates at a higher rate than healthy cells. Through calcium analysis, no differences in contractile activation in response to histamine were found. However, CF ASM cells lagged in their reuptake of calcium in the sarcoplasmic reticulum. The combination CFTR corrector and potentiator, VX-809/770, used to restore CFTR function in CF ASM, resulted in a reduction in proliferation and in a normalization of calcium reuptake kinetics. These results show that impaired CFTR function in ASM cells causes intrinsic changes in their proliferative and contractile properties.
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Affiliation(s)
- Joyce Hojin Jang
- Meakins-Christie Laboratories, McGill University Health Center and McGill University, Montreal, Quebec, Canada
- Department of Medicine, McGill University, Montreal, Quebec, Canada
| | - Alice Panariti
- Meakins-Christie Laboratories, McGill University Health Center and McGill University, Montreal, Quebec, Canada
| | - Michael J. O’Sullivan
- Meakins-Christie Laboratories, McGill University Health Center and McGill University, Montreal, Quebec, Canada
| | - Melissa Pyrch
- Meakins-Christie Laboratories, McGill University Health Center and McGill University, Montreal, Quebec, Canada
| | - Chris Wong
- Meakins-Christie Laboratories, McGill University Health Center and McGill University, Montreal, Quebec, Canada
| | - Anne-Marie Lauzon
- Meakins-Christie Laboratories, McGill University Health Center and McGill University, Montreal, Quebec, Canada
- Department of Medicine, McGill University, Montreal, Quebec, Canada
| | - James G. Martin
- Meakins-Christie Laboratories, McGill University Health Center and McGill University, Montreal, Quebec, Canada
- Department of Medicine, McGill University, Montreal, Quebec, Canada
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21
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Gazzola M, Khadangi F, Clisson M, Beaudoin J, Clavel MA, Bossé Y. Shortening of airway smooth muscle is modulated by prolonging the time without simulated deep inspirations in ovine tracheal strips. J Appl Physiol (1985) 2019; 127:1528-1538. [PMID: 31545157 DOI: 10.1152/japplphysiol.00423.2019] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The shortening of airway smooth muscle (ASM) is greatly affected by time. This is because stimuli affecting ASM shortening, such as bronchoactive molecules or the strain inflicted by breathing maneuvers, not only alter quick biochemical processes regulating contraction but also slower processes that allow ASM to adapt to an ever-changing length. Little attention has been given to the effect of time on ASM shortening. The present study investigates the effect of changing the time interval between simulated deep inspirations (DIs) on ASM shortening and its responsiveness to simulated DIs. Excised tracheal strips from sheep were mounted in organ baths and either activated with methacholine or relaxed with isoproterenol. They were then subjected to simulated DIs by imposing swings in distending stress, emulating a transmural pressure from 5 to 30 cmH2O. The simulated DIs were intercalated by 2, 5, 10, or 30 min. In between simulated DIs, the distending stress was either fixed or oscillating to simulate tidal breathing. The results show that although shortening was increased by prolonging the interval between simulated DIs, the bronchodilator effect of simulated DIs (i.e., the elongation of the strip post- vs. pre-DI) was not affected, and the rate of re-shortening post-simulated DIs was decreased. As the frequency with which DIs are taken increases upon bronchoconstriction, our results may be relevant to typical alterations observed in asthma, such as an increased rate of re-narrowing post-DI.NEW & NOTEWORTHY The frequency with which patients with asthma take deep inspirations (DIs) increases during bronchoconstriction. This in vitro study investigated the effect of changing the time interval between simulated DIs on airway smooth muscle shortening. The results demonstrated that decreasing the interval between simulated DIs not only decreases shortening, which may be protective against excessive airway narrowing, but also increases the rate of re-shortening post-simulated DIs, which may contribute to the increased rate of re-narrowing post-DI observed in asthma.
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22
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Noble PB, Kowlessur D, Larcombe AN, Donovan GM, Wang KCW. Mechanical Abnormalities of the Airway Wall in Adult Mice After Intrauterine Growth Restriction. Front Physiol 2019; 10:1073. [PMID: 31507442 PMCID: PMC6716216 DOI: 10.3389/fphys.2019.01073] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Accepted: 08/05/2019] [Indexed: 11/19/2022] Open
Abstract
Developmental abnormalities of airways may impact susceptibility to asthma in later life. We used a maternal hypoxia-induced mouse model of intrauterine growth restriction (IUGR) to examine changes in mechanical properties of the airway wall. Pregnant BALB/c mice were housed under hypoxic conditions (10.5% O2) from gestational day (GD) 11 to GD 17.5 (IUGR; term, GD 21). Following hypoxic exposure, mice were returned to a normoxic environment (21% O2). A control group of pregnant mice were housed under normoxic conditions throughout pregnancy. At 8 weeks postnatal age, offspring were euthanized and a tracheasectomy performed. Tracheal segments were studied in organ baths to measure active airway smooth muscle (ASM) stress to carbachol and assess passive mechanical properties (stiffness) from stress-strain curves. In a separate group of anesthetized offspring, the forced oscillation technique was used to examine airway mechanics from relative changes in airway conductance during slow inflation and deflation between 0 and 20 cmH2O transrespiratory pressure. From predicted radius-pressure loops, storage and loss moduli and hysteresivity were calculated. IUGR offspring were lighter at birth (p < 0.05) and remained lighter at 8 weeks of age (p < 0.05) compared with Controls. Maximal stress was reduced in male IUGR offspring compared with Controls (p < 0.05), but not in females. Sensitivity to contractile agonist was not affected by IUGR or sex. Compared with the Control group, airways from IUGR animals were stiffer in vitro (p < 0.05). In vivo, airway hysteresivity (p < 0.05) was increased in the IUGR group, but there was no difference in storage or loss moduli between groups. In summary, the effects of IUGR persist to the mature airway wall, where there are clear abnormalities to ASM contractile properties and passive wall mechanics. We propose that mechanical abnormalities of the airway wall acquired through disrupted fetal growth impact susceptibility to disease.
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Affiliation(s)
- Peter B Noble
- School of Human Sciences, University of Western Australia, Perth, WA, Australia
| | - Darshinee Kowlessur
- School of Human Sciences, University of Western Australia, Perth, WA, Australia.,Telethon Kids Institute, University of Western Australia, Perth, WA, Australia
| | - Alexander N Larcombe
- Telethon Kids Institute, University of Western Australia, Perth, WA, Australia.,School of Public Health, Curtin University, Perth, WA, Australia
| | - Graham M Donovan
- Department of Mathematics, University of Auckland, Auckland, New Zealand
| | - Kimberley C W Wang
- School of Human Sciences, University of Western Australia, Perth, WA, Australia.,Telethon Kids Institute, University of Western Australia, Perth, WA, Australia
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23
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Noble PB, Kowlessur D, Larcombe AN, Donovan GM, Wang KCW. Mechanical Abnormalities of the Airway Wall in Adult Mice After Intrauterine Growth Restriction. Front Physiol 2019. [PMID: 31507442 PMCID: PMC6716216 DOI: 10.3389/fphys.2019.01073,+10.3389/fpls.2019.01073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Developmental abnormalities of airways may impact susceptibility to asthma in later life. We used a maternal hypoxia-induced mouse model of intrauterine growth restriction (IUGR) to examine changes in mechanical properties of the airway wall. Pregnant BALB/c mice were housed under hypoxic conditions (10.5% O2) from gestational day (GD) 11 to GD 17.5 (IUGR; term, GD 21). Following hypoxic exposure, mice were returned to a normoxic environment (21% O2). A control group of pregnant mice were housed under normoxic conditions throughout pregnancy. At 8 weeks postnatal age, offspring were euthanized and a tracheasectomy performed. Tracheal segments were studied in organ baths to measure active airway smooth muscle (ASM) stress to carbachol and assess passive mechanical properties (stiffness) from stress-strain curves. In a separate group of anesthetized offspring, the forced oscillation technique was used to examine airway mechanics from relative changes in airway conductance during slow inflation and deflation between 0 and 20 cmH2O transrespiratory pressure. From predicted radius-pressure loops, storage and loss moduli and hysteresivity were calculated. IUGR offspring were lighter at birth (p < 0.05) and remained lighter at 8 weeks of age (p < 0.05) compared with Controls. Maximal stress was reduced in male IUGR offspring compared with Controls (p < 0.05), but not in females. Sensitivity to contractile agonist was not affected by IUGR or sex. Compared with the Control group, airways from IUGR animals were stiffer in vitro (p < 0.05). In vivo, airway hysteresivity (p < 0.05) was increased in the IUGR group, but there was no difference in storage or loss moduli between groups. In summary, the effects of IUGR persist to the mature airway wall, where there are clear abnormalities to ASM contractile properties and passive wall mechanics. We propose that mechanical abnormalities of the airway wall acquired through disrupted fetal growth impact susceptibility to disease.
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Affiliation(s)
- Peter B. Noble
- School of Human Sciences, University of Western Australia, Perth, WA, Australia
| | - Darshinee Kowlessur
- School of Human Sciences, University of Western Australia, Perth, WA, Australia,Telethon Kids Institute, University of Western Australia, Perth, WA, Australia
| | - Alexander N. Larcombe
- Telethon Kids Institute, University of Western Australia, Perth, WA, Australia,School of Public Health, Curtin University, Perth, WA, Australia
| | - Graham M. Donovan
- Department of Mathematics, University of Auckland, Auckland, New Zealand
| | - Kimberley C. W. Wang
- School of Human Sciences, University of Western Australia, Perth, WA, Australia,Telethon Kids Institute, University of Western Australia, Perth, WA, Australia,*Correspondence: Kimberley C. W. Wang,
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24
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Noble PB, Kowlessur D, Larcombe AN, Donovan GM, Wang KCW. Mechanical Abnormalities of the Airway Wall in Adult Mice After Intrauterine Growth Restriction. Front Physiol 2019. [PMID: 31507442 DOI: 10.3389/fphys.2019.01073, 10.3389/fpls.2019.01073] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Developmental abnormalities of airways may impact susceptibility to asthma in later life. We used a maternal hypoxia-induced mouse model of intrauterine growth restriction (IUGR) to examine changes in mechanical properties of the airway wall. Pregnant BALB/c mice were housed under hypoxic conditions (10.5% O2) from gestational day (GD) 11 to GD 17.5 (IUGR; term, GD 21). Following hypoxic exposure, mice were returned to a normoxic environment (21% O2). A control group of pregnant mice were housed under normoxic conditions throughout pregnancy. At 8 weeks postnatal age, offspring were euthanized and a tracheasectomy performed. Tracheal segments were studied in organ baths to measure active airway smooth muscle (ASM) stress to carbachol and assess passive mechanical properties (stiffness) from stress-strain curves. In a separate group of anesthetized offspring, the forced oscillation technique was used to examine airway mechanics from relative changes in airway conductance during slow inflation and deflation between 0 and 20 cmH2O transrespiratory pressure. From predicted radius-pressure loops, storage and loss moduli and hysteresivity were calculated. IUGR offspring were lighter at birth (p < 0.05) and remained lighter at 8 weeks of age (p < 0.05) compared with Controls. Maximal stress was reduced in male IUGR offspring compared with Controls (p < 0.05), but not in females. Sensitivity to contractile agonist was not affected by IUGR or sex. Compared with the Control group, airways from IUGR animals were stiffer in vitro (p < 0.05). In vivo, airway hysteresivity (p < 0.05) was increased in the IUGR group, but there was no difference in storage or loss moduli between groups. In summary, the effects of IUGR persist to the mature airway wall, where there are clear abnormalities to ASM contractile properties and passive wall mechanics. We propose that mechanical abnormalities of the airway wall acquired through disrupted fetal growth impact susceptibility to disease.
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Affiliation(s)
- Peter B Noble
- School of Human Sciences, University of Western Australia, Perth, WA, Australia
| | - Darshinee Kowlessur
- School of Human Sciences, University of Western Australia, Perth, WA, Australia.,Telethon Kids Institute, University of Western Australia, Perth, WA, Australia
| | - Alexander N Larcombe
- Telethon Kids Institute, University of Western Australia, Perth, WA, Australia.,School of Public Health, Curtin University, Perth, WA, Australia
| | - Graham M Donovan
- Department of Mathematics, University of Auckland, Auckland, New Zealand
| | - Kimberley C W Wang
- School of Human Sciences, University of Western Australia, Perth, WA, Australia.,Telethon Kids Institute, University of Western Australia, Perth, WA, Australia
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25
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Komatsu S, Wang L, Seow CY, Ikebe M. p116 Rip promotes myosin phosphatase activity in airway smooth muscle cells. J Cell Physiol 2019; 235:114-127. [PMID: 31347175 DOI: 10.1002/jcp.28949] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Revised: 05/22/2019] [Accepted: 05/23/2019] [Indexed: 12/28/2022]
Abstract
Myosin phosphatase-Rho interacting protein (p116Rip ) was originally found as a RhoA-binding protein. Subsequent studies by us and others revealed that p116Rip facilitates myosin light chain phosphatase (MLCP) activity through direct and indirect manners. However, it is unclear how p116Rip regulates myosin phosphatase activity in cells. To elucidate the role of p116Rip in cellular contractile processes, we suppressed the expression of p116Rip by RNA interference in human airway smooth muscle cells (HASMCs). We found that knockdown of p116Rip in HASMCs led to increased di-phosphorylated MLC (pMLC), that is phosphorylation at both Ser19 and Thr18. This was because of a change in the interaction between MLCP and myosin, but not an alteration of RhoA/ROCK signaling. Attenuation of Zipper-interacting protein kinase (ZIPK) abolished the increase in di-pMLC, suggesting that ZIPK is involved in this process. Moreover, suppression of p116Rip expression in HASMCs substantially increased the histamine-induced collagen gel contraction. We also found that expression of the p116Rip was decreased in the airway smooth muscle tissue from asthmatic patients compared with that from non-asthmatic patients, suggesting a potential role of p116Rip expression in asthma pathogenesis.
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Affiliation(s)
- Satoshi Komatsu
- Department of Cellular and Molecular Biology, The University of Texas Health Science Center at Tyler, Tyler, Texas
| | - Lu Wang
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Chun Y Seow
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Mitsuo Ikebe
- Department of Cellular and Molecular Biology, The University of Texas Health Science Center at Tyler, Tyler, Texas
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26
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The β-adrenergic theory of bronchial asthma: 50 years later. J Allergy Clin Immunol 2019; 144:1166-1168. [PMID: 31344383 DOI: 10.1016/j.jaci.2019.07.010] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Revised: 06/25/2019] [Accepted: 07/12/2019] [Indexed: 11/20/2022]
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27
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Donovan GM, Elliot JG, Green FHY, James AL, Noble PB. Unraveling a Clinical Paradox: Why Does Bronchial Thermoplasty Work in Asthma? Am J Respir Cell Mol Biol 2019; 59:355-362. [PMID: 29668295 DOI: 10.1165/rcmb.2018-0011oc] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Bronchial thermoplasty is a relatively new but seemingly effective treatment in subjects with asthma who do not respond to conventional therapy. Although the favored mechanism is ablation of the airway smooth muscle layer, because bronchial thermoplasty treats only a small number of central airways, there is ongoing debate regarding its precise method of action. Our aim in the present study was to elucidate the underlying method of action behind bronchial thermoplasty. We employed a combination of extensive human lung specimens and novel computational methods. Whole left lungs were acquired from the Prairie Provinces Fatal Asthma Study. Subjects were classified as control (n = 31), nonfatal asthma (n = 32), or fatal asthma (n = 25). Simulated lungs for each group were constructed stochastically, and flow distributions and functional indicators (e.g., resistance) were quantified both before and after a 75% reduction in airway smooth muscle in the "thermoplasty-treated" airways. Bronchial thermoplasty triggered global redistribution of clustered flow patterns wherein structural changes to the treated central airways led to a reopening cascade in the small airways and significant improvement in lung function via reduced spatial heterogeneity of flow patterns. This mechanism accounted for progressively greater efficacy of thermoplasty with both severity of asthma and degree of muscle activation, broadly consistent with existing clinical findings. We report a probable mechanism of action for bronchial thermoplasty: alteration of lung-wide flow patterns in response to structural alteration of the treated central airways. This insight could lead to improved therapy via patient-specific, tailored versions of the treatment-as well as to implications for more conventional asthma therapies.
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Affiliation(s)
- Graham M Donovan
- 1 Department of Mathematics, University of Auckland, Auckland, New Zealand
| | - John G Elliot
- 2 West Australian Sleep Disorders Research Institute, Department of Pulmonary Physiology and Sleep Medicine, and
| | - Francis H Y Green
- 3 Airway Inflammation Group, Snyder Institute of Chronic Diseases, Faculty of Medicine, University of Calgary, Calgary, Alberta, Canada; and
| | - Alan L James
- 2 West Australian Sleep Disorders Research Institute, Department of Pulmonary Physiology and Sleep Medicine, and.,4 Busselton Population Medical Research Institute, Sir Charles Gairdner Hospital, Nedlands, Western Australia, Australia
| | - Peter B Noble
- 5 School of Human Sciences and.,6 Centre for Neonatal Research and Education, School of Paediatrics and Child Health, The University of Western Australia, Subiaco, Western Australia, Australia
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28
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Hai CM. Prestrain and cholinergic receptor-dependent differential recruitment of mechanosensitive energy loss and energy release elements in airway smooth muscle. J Appl Physiol (1985) 2019; 126:823-831. [PMID: 30653417 DOI: 10.1152/japplphysiol.01008.2018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
We tested the hypothesis that oscillatory airway smooth muscle (ASM) mechanics is governed by mechanosensitive energy loss and energy release elements that can be recruited by prestrain and cholinergic stimulation. We measured mechanical energy loss and mechanical energy release in unstimulated and carbachol-stimulated bovine ASM held at prestrains ranging from 0.3 to 1.0 Lo (reference length) and subjected to sinusoidal length oscillation at 1 hz with oscillatory strain amplitudes ranging from 0.1 to 1.5% Lo. We found that oscillatory ASM mechanics during sinusoidal length oscillation is governed predominantly by one class of nonlinear mechanosensitive energy loss element and one class of nonlinear mechanosensitive energy release element with differential mechanosensitivities to oscillatory strain amplitude. The greater mechanosensitivity of the energy loss element than energy release element may explain the bronchodilatory effect of deep inspiration. Prestrain, an important determinant of ASM responsiveness, differentially increased energy loss and energy release in unstimulated and carbachol-stimulated ASM. Cholinergic stimulation, an important cause of bronchoconstriction and airway inflammation, also differentially increased energy loss and energy release. When prestrain and cholinergic stimulation were combined, we found that prestrain and cholinergic stimulation synergistically increased energy loss and energy release by ASM. The relationship between recruitment of energy loss elements and recruitment of energy release elements was nonlinear, suggesting that energy loss and energy release elements are not coupled in ASM cells. These findings imply that large lung volume and cholinergic ASM activation would synergistically increase mechanical energy expenditure during inspiration and mechanical recoil of ASM during expiration. NEW & NOTEWORTHY We report for the first time that oscillatory airway smooth muscle mechanics is governed predominantly by one class of nonlinear mechanosensitive energy loss element and one class of nonlinear mechanosensitive energy release element with differential mechanosensitivities to oscillatory strain amplitude. Prestrain and cholinergic stimulation synergistically and differentially recruit energy loss and energy release elements. The greater mechanosensitivity of the energy loss element than the energy release element may explain the bronchodilatory effect of deep inspiration.
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Affiliation(s)
- Chi-Ming Hai
- Department of Molecular Pharmacology, Physiology, and Biotechnology, Brown University , Providence, Rhode Island
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29
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Bossé Y. The Strain on Airway Smooth Muscle During a Deep Inspiration to Total Lung Capacity. JOURNAL OF ENGINEERING AND SCIENCE IN MEDICAL DIAGNOSTICS AND THERAPY 2019; 2:0108021-1080221. [PMID: 32328568 PMCID: PMC7164505 DOI: 10.1115/1.4042309] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Revised: 11/06/2018] [Indexed: 02/05/2023]
Abstract
The deep inspiration (DI) maneuver entices a great deal of interest because of its ability to temporarily ease the flow of air into the lungs. This salutary effect of a DI is proposed to be mediated, at least partially, by momentarily increasing the operating length of airway smooth muscle (ASM). Concerningly, this premise is largely derived from a growing body of in vitro studies investigating the effect of stretching ASM by different magnitudes on its contractility. The relevance of these in vitro findings remains uncertain, as the real range of strains ASM undergoes in vivo during a DI is somewhat elusive. In order to understand the regulation of ASM contractility by a DI and to infer on its putative contribution to the bronchodilator effect of a DI, it is imperative that in vitro studies incorporate levels of strains that are physiologically relevant. This review summarizes the methods that may be used in vivo in humans to estimate the strain experienced by ASM during a DI from functional residual capacity (FRC) to total lung capacity (TLC). The strengths and limitations of each method, as well as the potential confounders, are also discussed. A rough estimated range of ASM strains is provided for the purpose of guiding future in vitro studies that aim at quantifying the regulatory effect of DI on ASM contractility. However, it is emphasized that, owing to the many limitations and confounders, more studies will be needed to reach conclusive statements.
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Affiliation(s)
- Ynuk Bossé
- Université Laval, Faculty of Medicine, Department of Medicine, IUCPQ, M2694, Pavillon Mallet, Chemin Sainte-Foy, Québec, QC G1V 4G5, Canada e-mail:
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30
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Mailhot-Larouche S, Bossé Y. Interval between simulated deep inspirations on the dynamics of airway smooth muscle contraction in guinea pig bronchi. Respir Physiol Neurobiol 2018; 259:136-142. [PMID: 30217723 DOI: 10.1016/j.resp.2018.09.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2018] [Revised: 09/06/2018] [Accepted: 09/10/2018] [Indexed: 11/26/2022]
Abstract
A certain amount of time is required to achieve a maximal contraction from airway smooth muscle (ASM) and stretches of substantial magnitude, such as the ones imparted by deep inspirations (DIs), interfere with contraction. The duration of ASM contraction without interference may thus affect its shortening, its mechanical response to DIs and the overall toll it exerts on the respiratory system. In this study, the effect of changing the interval between DIs on the dynamics of ASM was examined in vitro. Isolated bronchi derived from guinea pigs were held isotonically and stimulated to both contract and relax, in a randomized order, in response to 10-5 M of methacholine and 10-6 M of isoproterenol, respectively. Interference to ASM was inflicted after 2, 5, 10 and 30 min in a randomized order, by imposing a stretch that simulated a DI. The shortening before the stretch, the stiffness before and during the stretch, the post-stretch elongation of ASM and the ensuing re-shortening were measured. These experiments were also performed in the presence of simulated tidal breathing achieved through force fluctuations. The results demonstrate that, with or without force fluctuations, increasing the interval between simulated DIs increased shortening and post-stretch elongation, but not stiffness and re-shortening. These time-dependent effects were not observed when ASM was held in the relaxed state. These findings may help understand to which extent ASM shortening and the regulatory effect of DI are affected by changing the interval between DIs. The potential consequences of these findings on airway narrowing are also discussed.
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31
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Ijpma G, Liang CQ, Kachmar L, Panariti A, Benedetti A, Lavoie JP, Lauzon AM. Maintenance of contractile function of isolated airway smooth muscle after cryopreservation. Am J Physiol Lung Cell Mol Physiol 2018; 315:L724-L733. [PMID: 30091377 DOI: 10.1152/ajplung.00064.2018] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Isolated human airway smooth muscle (ASM) tissue contractility studies are essential for understanding the role of ASM in respiratory disease, but limited availability and cost render storage options necessary for optimal use. However, to our knowledge, no comprehensive study of cryopreservation protocols for isolated ASM has been performed to date. We tested several cryostorage protocols on equine trachealis ASM using different cryostorage media [1.8 M dimethyl sulfoxide and fetal bovine serum (FBS) or Krebs-Henseleit (KH)] and different degrees of dissection (with or without epithelium and connective tissues attached) before storage. We measured methacholine (MCh), histamine, and isoproterenol (Iso) dose-responses and electrical field stimulation (EFS) and MCh force-velocity curves. We confirmed our findings in human trachealis ASM stored undissected in FBS. Maximal stress response to MCh was decreased more in dissected than undissected equine tissues. EFS force was decreased in all equine but not in human cryostored tissues. Furthermore, in human cryostored tissues, EFS maximal shortening velocity was decreased, and Iso response was potentiated after cryostorage. Overnight incubation with 0.5 or 10% FBS did not recover contractility in the equine tissues but potentiated Iso response. Overnight incubation with 10% FBS in human tissues showed maximal stress recovery and maintenance of other contractile parameters. ASM tissues can be cryostored while maintaining most contractile function. We propose an optimal protocol for cryostorage of ASM as undissected tissues in FBS or KH solution followed by dissection of the ASM bundles and a 24-h incubation with 10% FBS before mechanics measurements.
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Affiliation(s)
- Gijs Ijpma
- Department of Medicine, McGill University , Montreal, Quebec , Canada.,Meakins-Christie Laboratories, Research Institute of the McGill University Health Centre , Montreal, Quebec , Canada
| | - Chu Qiao Liang
- Department of Medicine, McGill University , Montreal, Quebec , Canada
| | - Linda Kachmar
- Department of Medicine, McGill University , Montreal, Quebec , Canada.,Meakins-Christie Laboratories, Research Institute of the McGill University Health Centre , Montreal, Quebec , Canada
| | - Alice Panariti
- Department of Medicine, McGill University , Montreal, Quebec , Canada.,Meakins-Christie Laboratories, Research Institute of the McGill University Health Centre , Montreal, Quebec , Canada
| | - Andrea Benedetti
- Department of Medicine, McGill University , Montreal, Quebec , Canada.,Department of Epidemiology, Biostatistics, and Occupational Health, McGill University , Montreal, Quebec , Canada.,Respiratory Epidemiology and Clinical Research Unit, McGill University Health Centre , Montreal, Quebec , Canada
| | - Jean-Pierre Lavoie
- Faculty of Veterinary Medicine, Department of Clinical Sciences, University of Montreal , Saint-Hyacinthe, Quebec , Canada
| | - Anne-Marie Lauzon
- Department of Medicine, McGill University , Montreal, Quebec , Canada.,Meakins-Christie Laboratories, Research Institute of the McGill University Health Centre , Montreal, Quebec , Canada
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32
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Martin JG. Airway smooth muscle may drive mucus hypersecretion in asthma. Eur Respir J 2018; 52:52/2/1801166. [PMID: 30093557 DOI: 10.1183/13993003.01166-2018] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Accepted: 07/02/2018] [Indexed: 02/03/2023]
Affiliation(s)
- James G Martin
- Dept of Medicine, Division of Respiratory Medicine, Faculty of Medicine, McGill University, Montreal, QC, Canada .,Meakins-Christie Laboratories, Research Institute of the McGill University Health Centre, Montreal, QC, Canada
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33
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Lutchen KR, Paré PD, Seow CY. Hyperresponsiveness: Relating the Intact Airway to the Whole Lung. Physiology (Bethesda) 2018; 32:322-331. [PMID: 28615315 DOI: 10.1152/physiol.00008.2017] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2017] [Revised: 05/10/2017] [Accepted: 05/10/2017] [Indexed: 11/22/2022] Open
Abstract
We relate changes of the airway wall to the response of the intact airway and the whole lung. We address how mechanical conditions and specific structural changes for an airway contribute to hyperresponsiveness resistant to deep inspiration. This review conveys that the origins of hyperresponsiveness do not devolve into an abnormality at single structural level but require examination of the complex interplay of all the parts.
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Affiliation(s)
- Kenneth R Lutchen
- Department of Biomedical Engineering, Boston University, Boston, Massachusetts
| | - Peter D Paré
- Department of Medicine, Respiratory Division, University of British Columbia, Vancouver, British Columbia, Canada.,Centre for Heart Lung Innovation-St. Paul's Hospital, University of British Columbia, Vancouver, British Columbia, Canada; and
| | - Chun Y Seow
- Centre for Heart Lung Innovation-St. Paul's Hospital, University of British Columbia, Vancouver, British Columbia, Canada; and.,Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, British Columbia, Canada
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34
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Affiliation(s)
- Klaus F Rabe
- 1 LungenClinic Grosshansdorf and.,2 Department of Medicine, Christian Albrechts University Kiel, Airway Research Center North, German Center for Lung Research, Grosshansdorf, Germany
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35
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O’Sullivan MJ, Gabriel E, Panariti A, Park CY, Ijpma G, Fredberg JJ, Lauzon AM, Martin JG. Epithelial Cells Induce a Cyclo-Oxygenase-1-Dependent Endogenous Reduction in Airway Smooth Muscle Contractile Phenotype. Am J Respir Cell Mol Biol 2017; 57:683-691. [PMID: 28708434 PMCID: PMC5765417 DOI: 10.1165/rcmb.2016-0427oc] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Accepted: 06/29/2017] [Indexed: 12/11/2022] Open
Abstract
Airway smooth muscle cells (ASMCs) are phenotypically regulated to exist in either a proliferative or a contractile state. However, the influence of other airway structural cell types on ASMC phenotype is largely unknown. Although epithelial cells are known to drive ASM proliferation, their effects on the contractile phenotype are uncertain. In the current study, we tested the hypothesis that epithelial cells reduce the contractile phenotype of ASMCs. To do so, we measured force production by traction microscopy, gene and protein expression, as well as calcium release by Fura-2 ratiometric imaging. ASMCs incubated with epithelial-derived medium produced less force after histamine stimulation. We observed reduced expression of myocardin, α-smooth muscle actin, and calponin within ASMCs after coculture with epithelial cells. Peak calcium release in response to histamine was diminished, and depended on the synthesis of cyclo-oxygenase-1 products by ASM and on prostaglandin E receptors 2 and 4. Together, these in vitro results demonstrate that epithelial cells have the capacity to coordinately reduce ASM contraction by functional antagonism and by reduction of the expression of certain contractile proteins.
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Affiliation(s)
- Michael J. O’Sullivan
- Meakins-Christie Laboratories, McGill University Health Centre, Montreal, Quebec, Canada; and
| | - Elizabeth Gabriel
- Harvard T.H. Chan School of Public Health, Harvard University, Boston, Massachusetts
| | - Alice Panariti
- Meakins-Christie Laboratories, McGill University Health Centre, Montreal, Quebec, Canada; and
| | - Chan Y. Park
- Harvard T.H. Chan School of Public Health, Harvard University, Boston, Massachusetts
| | - Gijs Ijpma
- Meakins-Christie Laboratories, McGill University Health Centre, Montreal, Quebec, Canada; and
| | - Jeffrey J. Fredberg
- Harvard T.H. Chan School of Public Health, Harvard University, Boston, Massachusetts
| | - Anne-Marie Lauzon
- Meakins-Christie Laboratories, McGill University Health Centre, Montreal, Quebec, Canada; and
| | - James G. Martin
- Meakins-Christie Laboratories, McGill University Health Centre, Montreal, Quebec, Canada; and
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36
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Donovan GM. Inter-airway structural heterogeneity interacts with dynamic heterogeneity to determine lung function and flow patterns in both asthmatic and control simulated lungs. J Theor Biol 2017; 435:98-105. [PMID: 28867222 DOI: 10.1016/j.jtbi.2017.08.024] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Revised: 08/23/2017] [Accepted: 08/28/2017] [Indexed: 01/10/2023]
Abstract
Asthma is a disease involving both airway remodelling (e.g. thickening of the airway wall) and acute, reversible airway narrowing driven by airway smooth muscle contraction. Both of these processes are known to be heterogeneous, and in this study we consider a new theoretical model which considers the interactions of both mechanisms: structural heterogeneity (variation in airway remodelling) and dynamic heterogeneity (emergent variation in airway narrowing and flow). By integrating both types of inter-airway heterogeneity in a full human lung geometry, we are able to draw several insights regarding the mechanisms underlying observed ventilation heterogeneity. We show that: (1) bimodal ventilation distributions are driven by paradoxical contraction/dilation patterns for airways of all sizes; (2) structural heterogeneity differences between asthmatic and control subjects significantly influences resulting lung function, and observed ventilation heterogeneity patterns; and (3) individual airway dilation probabilities are uncorrelated with prior airway remodelling of that airway.
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Affiliation(s)
- G M Donovan
- Department of Mathematics, University of Auckland, New Zealand.
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37
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Salter B, Pray C, Radford K, Martin JG, Nair P. Regulation of human airway smooth muscle cell migration and relevance to asthma. Respir Res 2017; 18:156. [PMID: 28814293 PMCID: PMC5559796 DOI: 10.1186/s12931-017-0640-8] [Citation(s) in RCA: 71] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Accepted: 08/10/2017] [Indexed: 01/15/2023] Open
Abstract
Airway remodelling is an important feature of asthma pathogenesis. A key structural change inherent in airway remodelling is increased airway smooth muscle mass. There is emerging evidence to suggest that the migration of airway smooth muscle cells may contribute to cellular hyperplasia, and thus increased airway smooth muscle mass. The precise source of these cells remains unknown. Increased airway smooth muscle mass may be collectively due to airway infiltration of myofibroblasts, neighbouring airway smooth muscle cells in the bundle, or circulating hemopoietic progenitor cells. However, the relative contribution of each cell type is not well understood. In addition, although many studies have identified pro and anti-migratory agents of airway smooth muscle cells, whether these agents can impact airway remodelling in the context of human asthma, remains to be elucidated. As such, further research is required to determine the exact mechanism behind airway smooth muscle cell migration within the airways, how much this contributes to airway smooth muscle mass in asthma, and whether attenuating this migration may provide a therapeutic avenue for asthma. In this review article, we will discuss the current evidence with respect to the regulation of airway smooth muscle cell migration in asthma.
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Affiliation(s)
- Brittany Salter
- Firestone Institute for Respiratory Health, St Joseph’s Healthcare and Department of Medicine, 50 Charlton Avenue, East, Hamilton, ON L8N 4A6 Canada
| | - Cara Pray
- Firestone Institute for Respiratory Health, St Joseph’s Healthcare and Department of Medicine, 50 Charlton Avenue, East, Hamilton, ON L8N 4A6 Canada
| | - Katherine Radford
- Firestone Institute for Respiratory Health, St Joseph’s Healthcare and Department of Medicine, 50 Charlton Avenue, East, Hamilton, ON L8N 4A6 Canada
| | - James G. Martin
- Meakins Christie Laboratories, McGill University, Montreal, QC Canada
| | - Parameswaran Nair
- Firestone Institute for Respiratory Health, St Joseph’s Healthcare and Department of Medicine, 50 Charlton Avenue, East, Hamilton, ON L8N 4A6 Canada
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38
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Matusovsky OS, Kachmar L, Ijpma G, Bates G, Zitouni N, Benedetti A, Lavoie JP, Lauzon AM. Peripheral Airway Smooth Muscle, but Not the Trachealis, Is Hypercontractile in an Equine Model of Asthma. Am J Respir Cell Mol Biol 2017; 54:718-27. [PMID: 26473389 DOI: 10.1165/rcmb.2015-0180oc] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Heaves is a naturally occurring equine disease that shares many similarities with human asthma, including reversible antigen-induced bronchoconstriction, airway inflammation, and remodeling. The purpose of this study was to determine whether the trachealis muscle is mechanically representative of the peripheral airway smooth muscle (ASM) in an equine model of asthma. Tracheal and peripheral ASM of heaves-affected horses under exacerbation, or under clinical remission of the disease, and control horses were dissected and freed of epithelium to measure unloaded shortening velocity (Vmax), stress (force/cross-sectional area), methacholine effective concentration at which 50% of the maximum response is obtained, and stiffness. Myofibrillar Mg(2+)-ATPase activity, actomyosin in vitro motility, and contractile protein expression were also measured. Horses with heaves had significantly greater Vmax and Mg(2+)-ATPase activity in peripheral airway but not in tracheal smooth muscle. In addition, a significant correlation was found between Vmax and the time elapsed since the end of the corticosteroid treatment for the peripheral airways in horses with heaves. Maximal stress and stiffness were greater in the peripheral airways of the horses under remission compared with controls and the horses under exacerbation, potentially due to remodeling. Actomyosin in vitro motility was not different between controls and horses with heaves. These data demonstrate that peripheral ASM is mechanically and biochemically altered in heaves, whereas the trachealis behaves as in control horses. It is therefore conceivable that the trachealis muscle may not be representative of the peripheral ASM in human asthma either, but this will require further investigation.
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Affiliation(s)
- Oleg S Matusovsky
- 1 Meakins-Christie Laboratories, McGill University, Research Institute of the McGill University Health Center, Montreal, Quebec, Canada
| | - Linda Kachmar
- 1 Meakins-Christie Laboratories, McGill University, Research Institute of the McGill University Health Center, Montreal, Quebec, Canada
| | - Gijs Ijpma
- 1 Meakins-Christie Laboratories, McGill University, Research Institute of the McGill University Health Center, Montreal, Quebec, Canada
| | - Genevieve Bates
- 1 Meakins-Christie Laboratories, McGill University, Research Institute of the McGill University Health Center, Montreal, Quebec, Canada
| | - Nedjma Zitouni
- 1 Meakins-Christie Laboratories, McGill University, Research Institute of the McGill University Health Center, Montreal, Quebec, Canada
| | - Andrea Benedetti
- 2 Department of Medicine, McGill University, Montreal, Quebec, Canada.,3 Respiratory Epidemiology and Clinical Research Unit, Montreal Chest Institute, Montreal, Quebec, Canada.,4 Department of Epidemiology, Biostatistics, and Occupational Health, McGill University, Montreal, Quebec, Canada; and
| | - Jean-Pierre Lavoie
- 5 Department of Clinical Sciences, Faculty of Veterinary Medicine, University of Montreal, St.-Hyacinthe, Quebec, Canada
| | - Anne-Marie Lauzon
- 1 Meakins-Christie Laboratories, McGill University, Research Institute of the McGill University Health Center, Montreal, Quebec, Canada.,2 Department of Medicine, McGill University, Montreal, Quebec, Canada
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39
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Mailhot-Larouche S, Lortie K, Marsolais D, Flamand N, Bossé Y. An in vitro study examining the duration between deep inspirations on the rate of renarrowing. Respir Physiol Neurobiol 2017; 243:13-19. [PMID: 28487171 DOI: 10.1016/j.resp.2017.04.013] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Revised: 04/07/2017] [Accepted: 04/29/2017] [Indexed: 12/12/2022]
Abstract
The factors altering the bronchodilatory response to a deep inspiration (DI) in asthma are important to decipher. In this in vitro study, we investigated the effect of changing the duration between DIs on the rate of force recovery post-DI in guinea pig bronchi. The airway smooth muscle (ASM) within the main bronchi were submitted to length oscillation that simulated tidal breathing in different contractile states during 2, 5, 10 or 30min prior to a larger length excursion that simulated a DI. The contractile states of ASM were determined by adding either methacholine or isoproterenol. Irrespective of the contractile state, the duration between DIs neither affected the measured force during length oscillation nor the bronchodilator effect of DI. Contrastingly, the rate of force recovery post-DI in contracted state increased as the duration between DIs decreased. Similar results were obtained with contracted parenchymal strips. These findings suggest that changing the duration between DIs may alter the rate of ASM force recovery post-DI and thereby affect the rate of renarrowing and the duration of the respiratory relief afforded by DI.
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Affiliation(s)
- Samuel Mailhot-Larouche
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, Canada
| | - Katherine Lortie
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, Canada
| | - David Marsolais
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, Canada
| | - Nicolas Flamand
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, Canada
| | - Ynuk Bossé
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, Canada.
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40
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Mazzone SB, Undem BJ. Vagal Afferent Innervation of the Airways in Health and Disease. Physiol Rev 2017; 96:975-1024. [PMID: 27279650 DOI: 10.1152/physrev.00039.2015] [Citation(s) in RCA: 339] [Impact Index Per Article: 48.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Vagal sensory neurons constitute the major afferent supply to the airways and lungs. Subsets of afferents are defined by their embryological origin, molecular profile, neurochemistry, functionality, and anatomical organization, and collectively these nerves are essential for the regulation of respiratory physiology and pulmonary defense through local responses and centrally mediated neural pathways. Mechanical and chemical activation of airway afferents depends on a myriad of ionic and receptor-mediated signaling, much of which has yet to be fully explored. Alterations in the sensitivity and neurochemical phenotype of vagal afferent nerves and/or the neural pathways that they innervate occur in a wide variety of pulmonary diseases, and as such, understanding the mechanisms of vagal sensory function and dysfunction may reveal novel therapeutic targets. In this comprehensive review we discuss historical and state-of-the-art concepts in airway sensory neurobiology and explore mechanisms underlying how vagal sensory pathways become dysfunctional in pathological conditions.
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Affiliation(s)
- Stuart B Mazzone
- School of Biomedical Sciences, The University of Queensland, St Lucia, Brisbane, Australia; and Department of Medicine, Johns Hopkins University Medical School, Asthma & Allergy Center, Baltimore, Maryland
| | - Bradley J Undem
- School of Biomedical Sciences, The University of Queensland, St Lucia, Brisbane, Australia; and Department of Medicine, Johns Hopkins University Medical School, Asthma & Allergy Center, Baltimore, Maryland
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41
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Ijpma G, Panariti A, Lauzon AM, Martin JG. Directional preference of airway smooth muscle mass increase in human asthmatic airways. Am J Physiol Lung Cell Mol Physiol 2017; 312:L845-L854. [PMID: 28360113 DOI: 10.1152/ajplung.00353.2016] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Revised: 03/16/2017] [Accepted: 03/17/2017] [Indexed: 11/22/2022] Open
Abstract
Airway smooth muscle (ASM) orientation and morphology determine the ability of the muscle to constrict the airway. In asthma, ASM mass is increased, but it is unknown whether ASM orientation and morphology are altered as well or whether the remodeling at the source of the mass increase is ongoing. We dissected human airway trees from asthmatic and control lungs. Stained, intact airway sections were imaged in axial projection to show ASM bundle orientation, whereas cross-sectional histological slides were used to assess ASM area, bundle thickness, and ASM bundle-to-basement membrane distance. We also used these slides to assess cell size, proliferation, and apoptosis. We showed that ASM mass increase in cartilaginous airways is primarily the result of an increase of ASM bundle thickness (as measured radially in an airway cross section) and coincides with an increased distance of the ASM bundles to the airway perimeter. ASM orientation was unchanged in all airways. Apoptosis markers and cell size did not show differences between asthmatics and controls. Our findings show that ASM mass increase likely contributes to the airway-constricting capacity of the muscle. Both the increased bundle thickness and increased thickness of the airway wall inwards of the ASM bundles could further enhance this capacity. Turnover of ASM appears to be the same in airways and biopsies, but the lack of correlation between different markers of proliferation casts doubt on the specificity of markers generally used to assess proliferation.
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Affiliation(s)
- Gijs Ijpma
- Department of Medicine, McGill University, Montreal, Quebec, Canada; and.,Research Institute of the McGill University Health Centre, Meakins-Christie Laboratories, Montreal, Quebec, Canada
| | - Alice Panariti
- Department of Medicine, McGill University, Montreal, Quebec, Canada; and.,Research Institute of the McGill University Health Centre, Meakins-Christie Laboratories, Montreal, Quebec, Canada
| | - Anne-Marie Lauzon
- Department of Medicine, McGill University, Montreal, Quebec, Canada; and.,Research Institute of the McGill University Health Centre, Meakins-Christie Laboratories, Montreal, Quebec, Canada
| | - James G Martin
- Department of Medicine, McGill University, Montreal, Quebec, Canada; and .,Research Institute of the McGill University Health Centre, Meakins-Christie Laboratories, Montreal, Quebec, Canada
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Rosner SR, Pascoe CD, Blankman E, Jensen CC, Krishnan R, James AL, Elliot JG, Green FH, Liu JC, Seow CY, Park JA, Beckerle MC, Paré PD, Fredberg JJ, Smith MA. The actin regulator zyxin reinforces airway smooth muscle and accumulates in airways of fatal asthmatics. PLoS One 2017; 12:e0171728. [PMID: 28278518 PMCID: PMC5344679 DOI: 10.1371/journal.pone.0171728] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2016] [Accepted: 01/24/2017] [Indexed: 01/21/2023] Open
Abstract
Bronchospasm induced in non-asthmatic human subjects can be easily reversed by a deep inspiration (DI) whereas bronchospasm that occurs spontaneously in asthmatic subjects cannot. This physiological effect of a DI has been attributed to the manner in which a DI causes airway smooth muscle (ASM) cells to stretch, but underlying molecular mechanisms-and their failure in asthma-remain obscure. Using cells and tissues from wild type and zyxin-/- mice we report responses to a transient stretch of physiologic magnitude and duration. At the level of the cytoskeleton, zyxin facilitated repair at sites of stress fiber fragmentation. At the level of the isolated ASM cell, zyxin facilitated recovery of contractile force. Finally, at the level of the small airway embedded with a precision cut lung slice, zyxin slowed airway dilation. Thus, at each level zyxin stabilized ASM structure and contractile properties at current muscle length. Furthermore, when we examined tissue samples from humans who died as the result of an asthma attack, we found increased accumulation of zyxin compared with non-asthmatics and asthmatics who died of other causes. Together, these data suggest a biophysical role for zyxin in fatal asthma.
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Affiliation(s)
- Sonia R. Rosner
- Department of Environmental Health, Harvard School of Public Health, Boston, Massachusetts, United States of America
| | - Christopher D. Pascoe
- University of British Columbia Center for Heart Lung Innovation, St Paul Hospital, Vancouver, British Columbia, Canada
| | - Elizabeth Blankman
- Huntsman Cancer Institute, University of Utah, Salt Lake City, Utah, United States of America
| | - Christopher C. Jensen
- Huntsman Cancer Institute, University of Utah, Salt Lake City, Utah, United States of America
| | - Ramaswamy Krishnan
- Center for Vascular Biology Research, Beth Israel Deaconess Medical Center, Boston, Massachusetts, United States of America
| | - Alan L. James
- Department of Pulmonary Physiology and Sleep Medicine, West Australian Sleep Disorders Research Institute, Sir Charles Gairdner Hospital, Nedlands, West Australia, Australia
- School of Medicine and Pharmacology, University of Western Australia, Perth, Western Australia, Australia
| | - John G. Elliot
- Department of Pulmonary Physiology and Sleep Medicine, West Australian Sleep Disorders Research Institute, Sir Charles Gairdner Hospital, Nedlands, West Australia, Australia
| | - Francis H. Green
- Department of Pathology and Laboratory Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Jeffrey C. Liu
- University of British Columbia Center for Heart Lung Innovation, St Paul Hospital, Vancouver, British Columbia, Canada
| | - Chun Y. Seow
- University of British Columbia Center for Heart Lung Innovation, St Paul Hospital, Vancouver, British Columbia, Canada
| | - Jin-Ah Park
- Department of Environmental Health, Harvard School of Public Health, Boston, Massachusetts, United States of America
| | - Mary C. Beckerle
- Huntsman Cancer Institute, University of Utah, Salt Lake City, Utah, United States of America
- Department of Biology, University of Utah, Salt Lake City, Utah, United States of America
| | - Peter D. Paré
- University of British Columbia Center for Heart Lung Innovation, St Paul Hospital, Vancouver, British Columbia, Canada
| | - Jeffrey J. Fredberg
- Department of Environmental Health, Harvard School of Public Health, Boston, Massachusetts, United States of America
| | - Mark A. Smith
- Huntsman Cancer Institute, University of Utah, Salt Lake City, Utah, United States of America
- Department of Biology, University of Utah, Salt Lake City, Utah, United States of America
- * E-mail:
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Gendron DR, Lecours PB, Lemay AM, Beaulieu MJ, Huppé CA, Lee-Gosselin A, Flamand N, Don AS, Bissonnette É, Blanchet MR, Laplante M, Bourgoin SG, Bossé Y, Marsolais D. A Phosphorylatable Sphingosine Analog Induces Airway Smooth Muscle Cytostasis and Reverses Airway Hyperresponsiveness in Experimental Asthma. Front Pharmacol 2017; 8:78. [PMID: 28270767 PMCID: PMC5318459 DOI: 10.3389/fphar.2017.00078] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2016] [Accepted: 02/07/2017] [Indexed: 11/13/2022] Open
Abstract
In asthma, excessive bronchial narrowing associated with thickening of the airway smooth muscle (ASM) causes respiratory distress. Numerous pharmacological agents prevent experimental airway hyperresponsiveness (AHR) when delivered prophylactically. However, most fail to resolve this feature after disease is instated. Although sphingosine analogs are primarily perceived as immune modulators with the ability to prevent experimental asthma, they also influence processes associated with tissue atrophy, supporting the hypothesis that they could interfere with mechanisms sustaining pre-established AHR. We thus assessed the ability of a sphingosine analog (AAL-R) to reverse AHR in a chronic model of asthma. We dissected the pharmacological mechanism of this class of agents using the non-phosphorylatable chiral isomer AAL-S and the pre-phosphorylated form of AAL-R (AFD-R) in vivo and in human ASM cells. We found that a therapeutic course of AAL-R reversed experimental AHR in the methacholine challenge test, which was not replicated by dexamethasone or the non-phosphorylatable isomer AAL-S. AAL-R efficiently interfered with ASM cell proliferation in vitro, supporting the concept that immunomodulation is not necessary to interfere with cellular mechanisms sustaining AHR. Moreover, the sphingosine-1-phosphate lyase inhibitor SM4 and the sphingosine-1-phosphate receptor antagonist VPC23019 failed to inhibit proliferation, indicating that intracellular accumulation of sphingosine-1-phosphate or interference with cell surface S1P1/S1P3 activation, are not sufficient to induce cytostasis. Potent AAL-R-induced cytostasis specifically related to its ability to induce intracellular AFD-R accumulation. Thus, a sphingosine analog that possesses the ability to be phosphorylated in situ interferes with cellular mechanisms that beget AHR.
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Affiliation(s)
- David R Gendron
- Centre de Recherche de l'Institut Universitaire de Cardiologie et de Pneumologie de Québec, Québec QC, Canada
| | - Pascale B Lecours
- Centre de Recherche de l'Institut Universitaire de Cardiologie et de Pneumologie de Québec, Québec QC, Canada
| | - Anne-Marie Lemay
- Centre de Recherche de l'Institut Universitaire de Cardiologie et de Pneumologie de Québec, Québec QC, Canada
| | - Marie-Josée Beaulieu
- Centre de Recherche de l'Institut Universitaire de Cardiologie et de Pneumologie de Québec, Québec QC, Canada
| | - Carole-Ann Huppé
- Centre de Recherche de l'Institut Universitaire de Cardiologie et de Pneumologie de Québec, Québec QC, Canada
| | - Audrey Lee-Gosselin
- Centre de Recherche de l'Institut Universitaire de Cardiologie et de Pneumologie de Québec, Québec QC, Canada
| | - Nicolas Flamand
- Centre de Recherche de l'Institut Universitaire de Cardiologie et de Pneumologie de Québec, QuébecQC, Canada; Faculty of Medicine, Université Laval, QuébecQC, Canada
| | - Anthony S Don
- Centenary Institute and NHMRC Clinical Trials Centre, University of Sydney, Camperdown NSW, Australia
| | - Élyse Bissonnette
- Centre de Recherche de l'Institut Universitaire de Cardiologie et de Pneumologie de Québec, QuébecQC, Canada; Faculty of Medicine, Université Laval, QuébecQC, Canada
| | - Marie-Renée Blanchet
- Centre de Recherche de l'Institut Universitaire de Cardiologie et de Pneumologie de Québec, QuébecQC, Canada; Faculty of Medicine, Université Laval, QuébecQC, Canada
| | - Mathieu Laplante
- Centre de Recherche de l'Institut Universitaire de Cardiologie et de Pneumologie de Québec, QuébecQC, Canada; Faculty of Medicine, Université Laval, QuébecQC, Canada
| | - Sylvain G Bourgoin
- Faculty of Medicine, Université Laval, QuébecQC, Canada; Division of Infectious Diseases and Immunology, CHU de Québec Research Center, QuébecQC, Canada
| | - Ynuk Bossé
- Centre de Recherche de l'Institut Universitaire de Cardiologie et de Pneumologie de Québec, QuébecQC, Canada; Faculty of Medicine, Université Laval, QuébecQC, Canada
| | - David Marsolais
- Centre de Recherche de l'Institut Universitaire de Cardiologie et de Pneumologie de Québec, QuébecQC, Canada; Faculty of Medicine, Université Laval, QuébecQC, Canada
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44
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Nair P, Martin JG, Cockcroft DC, Dolovich M, Lemiere C, Boulet LP, O'Byrne PM. Airway Hyperresponsiveness in Asthma: Measurement and Clinical Relevance. THE JOURNAL OF ALLERGY AND CLINICAL IMMUNOLOGY-IN PRACTICE 2017; 5:649-659.e2. [PMID: 28163029 DOI: 10.1016/j.jaip.2016.11.030] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Accepted: 11/01/2016] [Indexed: 10/20/2022]
Abstract
Airway hyperresponsiveness is a characteristic feature of asthma, and its measurement is an important tool in its diagnosis. With a few caveats, methacholine bronchial provocation by a 2-minute tidal breathing method is highly sensitive; a negative test result (PC20 > 16 mg/mL, PD20 > 400 μg) rules out current asthma with reasonable certainty. A PC20 value of less than 1 mg/mL/PD20 value of less than 25 μg is highly specific (ie, diagnostic) but quite insensitive for asthma. For accurate interpretation of the test results, it is important to control and standardize technical factors that have an impact on nebulizer performance. In addition to its utility to relate symptoms such as cough, wheeze, and shortness of breath to variable airflow obstruction (ie, to diagnose current asthma), the test is useful to make a number of other clinical assessments. These include (1) evaluation of patients with occupational asthma, (2) evaluation of patients with exercise-induced respiratory symptoms, (3) evaluation of novel asthma medications, (4) evaluation of relative potency of inhaled bronchodilators, (5) as a biomarker to adjust anti-inflammatory therapy to improve clinical outcomes, and (6) in the evaluation of patients with severe asthma to rule out masqueraders such as laryngeal dysfunction. The actual mechanism of altered smooth muscle behavior in asthma that is assessed by direct (eg, methacholine) or indirect (eg, allergen) bronchial provocation remains one of the most fundamental questions related to asthma that needs to be determined. The test is underutilized in clinical practice.
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Affiliation(s)
- Parameswaran Nair
- Division of Respirology, Department of Medicine, McMaster University and St Joseph's Healthcare, Hamilton, Ontario, Canada.
| | - James G Martin
- Meakins Christie Laboratories and Department of Medicine, McGill University, Montreal, Quebec, Canada
| | - Donald C Cockcroft
- Division of Respirology, Department of Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Myrna Dolovich
- Division of Respirology, Department of Medicine, McMaster University and St Joseph's Healthcare, Hamilton, Ontario, Canada
| | - Catherine Lemiere
- Department of Medicine, Sacre Coeur Hospital, University of Montreal, Montreal, Quebec, Canada
| | - Louis-Philippe Boulet
- Division of Respirology, Department of Medicine, University of Laval, Laval, Quebec, Canada
| | - Paul M O'Byrne
- Division of Respirology, Department of Medicine, McMaster University and St Joseph's Healthcare, Hamilton, Ontario, Canada
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45
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Pascoe CD, Seow CY, Hackett TL, Paré PD, Donovan GM. Heterogeneity of airway wall dimensions in humans: a critical determinant of lung function in asthmatics and nonasthmatics. Am J Physiol Lung Cell Mol Physiol 2017; 312:L425-L431. [PMID: 28062484 DOI: 10.1152/ajplung.00421.2016] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Revised: 12/13/2016] [Accepted: 12/30/2016] [Indexed: 11/22/2022] Open
Abstract
Airway remodeling, a key feature of asthma, alters every layer of the airway wall but most strikingly the airway smooth muscle (ASM) layer. Airway remodeling in asthmatics contributes to fixed airflow obstruction and can amplify airway narrowing caused by ASM activation. Previous modeling studies have shown that the increase in ASM mass has the largest effect on increasing maximal airway narrowing. Simulated heterogeneity in the dimensions and properties of the airway wall can further amplify airway narrowing. Using measurements made on histological sections from donor lungs, we show for the first time that there is profound heterogeneity of ASM area and wall area in both nonasthmatics and asthmatics. Using a mathematical model, we found that this heterogeneity, together with changes in the mean values, contributes to an increased baseline resistance and elastance in asthmatics as well as a leftward shift in the responsiveness of the airways to a simulated agonist in both nonasthmatics and asthmatics. The ability of heterogeneous wall dimensions to shift the dose-response curve is largely due to an increased susceptibility for the small airways to close. This research confirms that heterogeneity of airway wall dimensions can contribute to exaggerated airway narrowing and provides an actual assessment of the magnitude of these effects.
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Affiliation(s)
- Christopher D Pascoe
- Department of Physiology and Pathophysiology, University of Manitoba, Winnipeg, Manitoba, Canada; .,Children's Hospital Research Institute of Manitoba, Winnipeg, Manitoba, Canada
| | - Chun Y Seow
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, British Columbia, Canada.,UBC Centre for Heart Lung Innovation, St. Paul's Hospital, Vancouver, British Columbia, Canada; and
| | - Tillie L Hackett
- Department of Anesthesiology, Pharmacology and Therapeutics, University of British Columbia, Vancouver, British Columbia, Canada.,UBC Centre for Heart Lung Innovation, St. Paul's Hospital, Vancouver, British Columbia, Canada; and
| | - Peter D Paré
- Respiratory Division, Department of Medicine, University of British Columbia, Vancouver, British Columbia, Canada.,UBC Centre for Heart Lung Innovation, St. Paul's Hospital, Vancouver, British Columbia, Canada; and
| | - Graham M Donovan
- Department of Mathematics, University of Auckland, Auckland, New Zealand
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46
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Gazzola M, Lortie K, Henry C, Mailhot-Larouche S, Chapman DG, Couture C, Seow CY, Paré PD, King GG, Boulet LP, Bossé Y. Airway smooth muscle tone increases airway responsiveness in healthy young adults. Am J Physiol Lung Cell Mol Physiol 2016; 312:L348-L357. [PMID: 27941076 DOI: 10.1152/ajplung.00400.2016] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Revised: 12/06/2016] [Accepted: 12/07/2016] [Indexed: 11/22/2022] Open
Abstract
Force adaptation, a process whereby sustained spasmogenic activation (viz., tone) of airway smooth muscle (ASM) increases its contractile capacity, has been reported in isolated ASM tissues in vitro, as well as in mice in vivo. The objective of the present study was to assess the effect of tone on airway responsiveness in humans. Ten healthy volunteers underwent methacholine challenge on two occasions. One challenge consisted of six serial doses of saline followed by a single high dose of methacholine. The other consisted of six low doses of methacholine 5 min apart followed by a higher dose. The cumulative dose was identical for both challenges. After both methacholine challenges, subjects took a deep inspiration (DI) to total lung capacity as another way to probe ASM mechanics. Responses to methacholine and the DI were measured using a multifrequency forced oscillation technique. Compared with a single high dose, the challenge preceded by tone led to an elevated response measured by respiratory system resistance (Rrs) and reactance at 5 Hz. However, there was no difference in the increase in Rrs at 19 Hz, suggesting a predominant effect on smaller airways. Increased tone also reduced the efficacy of DI, measured by an attenuated maximal dilation during the DI and an increased renarrowing post-DI. We conclude that ASM tone increases small airway responsiveness to inhaled methacholine and reduces the effectiveness of DI in healthy humans. This suggests that force adaptation may contribute to airway hyperresponsiveness and the reduced bronchodilatory effect of DI in asthma.
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Affiliation(s)
- Morgan Gazzola
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, Québec, Canada
| | - Katherine Lortie
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, Québec, Canada
| | - Cyndi Henry
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, Québec, Canada
| | - Samuel Mailhot-Larouche
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, Québec, Canada
| | - David G Chapman
- Vermont Lung Center, University of Vermont College of Medicine, Burlington, Vermont
| | - Christian Couture
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, Québec, Canada
| | - Chun Y Seow
- University of British Columbia Centre for Heart Lung Innovation, St. Paul's Hospital, Vancouver, British Columbia, Canada
| | - Peter D Paré
- University of British Columbia Centre for Heart Lung Innovation, St. Paul's Hospital, Vancouver, British Columbia, Canada
| | - Gregory G King
- Woolcock Institute of Medical Research, Sydney, Australia.,University of Sydney, Sydney, Australia; and.,Cooperative Research Centre for Asthma, Sydney, Australia
| | - Louis-Philippe Boulet
- 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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47
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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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48
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Regulation of actin dynamics by WNT-5A: implications for human airway smooth muscle contraction. Sci Rep 2016; 6:30676. [PMID: 27468699 PMCID: PMC4965744 DOI: 10.1038/srep30676] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Accepted: 07/07/2016] [Indexed: 01/13/2023] Open
Abstract
A defining feature of asthma is airway hyperresponsiveness (AHR), which underlies the exaggerated bronchoconstriction response of asthmatics. The role of the airway smooth muscle (ASM) in AHR has garnered increasing interest over the years, but how asthmatic ASM differs from healthy ASM is still an active topic of debate. WNT-5A is increasingly expressed in asthmatic ASM and has been linked with Th2-high asthma. Due to its link with calcium and cytoskeletal remodelling, we propose that WNT-5A may modulate ASM contractility. We demonstrated that WNT-5A can increase maximum isometric tension in bovine tracheal smooth muscle strips. In addition, we show that WNT-5A is preferentially expressed in contractile human airway myocytes compared to proliferative cells, suggesting an active role in maintaining contractility. Furthermore, WNT-5A treatment drives actin polymerisation, but has no effect on intracellular calcium flux. Next, we demonstrated that WNT-5A directly regulates TGF-β1-induced expression of α-SMA via ROCK-mediated actin polymerization. These findings suggest that WNT-5A modulates fundamental mechanisms that affect ASM contraction and thus may be of relevance for AHR in asthma.
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49
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Bates JHT. Systems physiology of the airways in health and obstructive pulmonary disease. WILEY INTERDISCIPLINARY REVIEWS-SYSTEMS BIOLOGY AND MEDICINE 2016; 8:423-37. [PMID: 27340818 DOI: 10.1002/wsbm.1347] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 02/26/2016] [Revised: 05/11/2016] [Accepted: 05/12/2016] [Indexed: 01/10/2023]
Abstract
Fresh air entering the mouth and nose is brought to the blood-gas barrier in the lungs by a repetitively branching network of airways. Provided the individual airway branches remain patent, this airway tree achieves an enormous amplification in cross-sectional area from the trachea to the terminal bronchioles. Obstructive lung diseases such as asthma occur when airway patency becomes compromised. Understanding the pathophysiology of these obstructive diseases thus begins with a consideration of the factors that determine the caliber of an individual airway, which include the force balance between the inward elastic recoil of the airway wall, the outward tethering forces of its parenchymal attachments, and any additional forces due to contraction of airway smooth muscle. Other factors may also contribute significantly to airway narrowing, such as thickening of the airway wall and accumulation of secretions in the lumen. Airway obstruction becomes particularly severe when these various factors occur in concert. However, the effect of airway abnormalities on lung function cannot be fully understood only in terms of what happens to a single airway because narrowing throughout the airway tree is invariably heterogeneous and interdependent. Obstructive lung pathologies thus manifest as emergent phenomena arising from the way in which the airway tree behaves a system. These emergent phenomena are studied with clinical measurements of lung function made by spirometry and by mechanical impedance measured with the forced oscillation technique. Anatomically based computational models are linking these measurements to underlying anatomic structure in systems physiology terms. WIREs Syst Biol Med 2016, 8:423-437. doi: 10.1002/wsbm.1347 For further resources related to this article, please visit the WIREs website.
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Affiliation(s)
- Jason H T Bates
- Department of Medicine, University of Vermont College of Medicine, Burlington, VT, USA
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50
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Qiao Y, Tam JKC, Tan SSL, Tai YK, Chin CY, Stewart AG, Ashman L, Sekiguchi K, Langenbach SY, Stelmack G, Halayko AJ, Tran T. CD151, a laminin receptor showing increased expression in asthmatic patients, contributes to airway hyperresponsiveness through calcium signaling. J Allergy Clin Immunol 2016; 139:82-92.e5. [PMID: 27233153 DOI: 10.1016/j.jaci.2016.03.029] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Revised: 02/22/2016] [Accepted: 03/15/2016] [Indexed: 11/28/2022]
Abstract
BACKGROUND Airway smooth muscle (ASM) contraction underpins airway constriction; however, underlying mechanisms for airway hyperresponsiveness (AHR) remain incompletely defined. CD151, a 4-transmembrane glycoprotein that associates with laminin-binding integrins, is highly expressed in the human lung. The role of CD151 in ASM function and its relationship to asthma have yet to be elucidated. OBJECTIVE We sought to ascertain whether CD151 expression is clinically relevant to asthma and whether CD151 expression affects AHR. METHODS Using immunohistochemical analysis, we determined the expression of CD151 in human bronchial biopsy specimens from patients with varying asthma severities and studied the mechanism of action of CD151 in the regulation of ASM contraction and bronchial caliber in vitro, ex vivo, and in vivo. RESULTS The number of CD151+ ASM cells is significantly greater in patients with moderate asthma compared with those in healthy nonasthmatic subjects. From loss- and gain-of-function studies, we reveal that CD151 is required for and enhances G protein-coupled receptor (GPCR)-induced peak intracellular calcium release, the primary determinant of excitation-contraction coupling. We show that the localization of CD151 can also be perinuclear/cytoplasmic and offer an explanation for a novel functional role for CD151 in supporting protein kinase C (PKC) translocation to the cell membrane in GPCR-mediated ASM contraction at this site. Importantly, CD151-/- mice are refractory to airway hyperreactivity in response to allergen challenge. CONCLUSIONS We identify a role for CD151 in human ASM contraction. We implicate CD151 as a determinant of AHR in vivo, likely through regulation of GPCR-induced calcium and PKC signaling. These observations have significant implications in understanding the mechanism for AHR and the efficacy of new and emerging therapeutics.
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Affiliation(s)
- Yongkang Qiao
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - John Kit Chung Tam
- Department of Surgery, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Sheryl S L Tan
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Yee Kit Tai
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Chin Yein Chin
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Alastair G Stewart
- Department of Pharmacology and Therapeutics, and Lung Health Research Centre, University of Melbourne, Melbourne, Australia
| | - Leonie Ashman
- School of Biomedical Sciences, University of Newcastle, Newcastle, Australia
| | | | - Shenna Y Langenbach
- Department of Pharmacology and Therapeutics, and Lung Health Research Centre, University of Melbourne, Melbourne, Australia
| | - Gerald Stelmack
- Department of Physiology and Pathophysiology, University of Manitoba, Winnipeg, Manitoba, Canada; Biology of Breathing Theme, Manitoba Institute of Child Health, Winnipeg, Manitoba, Canada
| | - Andrew J Halayko
- Department of Physiology and Pathophysiology, University of Manitoba, Winnipeg, Manitoba, Canada; Biology of Breathing Theme, Manitoba Institute of Child Health, Winnipeg, Manitoba, Canada
| | - Thai Tran
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.
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