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Carbajal-García A, Reyes-García J, Díaz-Hernández V, Casas-Hernández MF, Flores-Murrieta FJ, Montaño LM. Testosterone Enhances K V Currents and Airway Smooth Muscle Relaxation Induced by ATP and UTP through P2Y 4 Receptors and Adenylyl Cyclase Pathway. Int J Mol Sci 2024; 25:4652. [PMID: 38731872 PMCID: PMC11083821 DOI: 10.3390/ijms25094652] [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: 02/29/2024] [Revised: 04/07/2024] [Accepted: 04/17/2024] [Indexed: 05/13/2024] Open
Abstract
Numerous studies suggest the involvement of adenosine-5'-triphosphate (ATP) and similar nucleotides in the pathophysiology of asthma. Androgens, such as testosterone (TES), are proposed to alleviate asthma symptoms in young men. ATP and uridine-5'-triphosphate (UTP) relax the airway smooth muscle (ASM) via purinergic P2Y2 and P2Y4 receptors and K+ channel opening. We previously demonstrated that TES increased the expression of voltage-dependent K+ (KV) channels in ASM. This study investigates how TES may potentiate ASM relaxation induced by ATP and UTP. Tracheal tissues treated with or without TES (control group) from young male guinea pigs were used. In organ baths, tracheas exposed to TES (40 nM for 48 h) showed enhanced ATP- and UTP-evoked relaxation. Tetraethylammonium, a K+ channel blocker, annulled this effect. Patch-clamp experiments in tracheal myocytes showed that TES also increased ATP- and UTP-induced K+ currents, and this effect was abolished with flutamide (an androgen receptor antagonist). KV channels were involved in this phenomenon, which was demonstrated by inhibition with 4-aminopyridine. RB2 (an antagonist of almost all P2Y receptors except for P2Y2), as well as N-ethylmaleimide and SQ 22,536 (inhibitors of G proteins and adenylyl cyclase, respectively), attenuated the enhancement of the K+ currents induced by TES. Immunofluorescence and immunohistochemistry studies revealed that TES did not modify the expression of P2Y4 receptors or COX-1 and COX-2, while we have demonstrated that this androgen augmented the expression of KV1.2 and KV1.5 channels in ASM. Thus, TES leads to the upregulation of P2Y4 signaling and KV channels in guinea pig ASM, enhancing ATP and UTP relaxation responses, which likely limits the severity of bronchospasm in young males.
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Affiliation(s)
- Abril Carbajal-García
- Departamento de Farmacología, Facultad de Medicina, Universidad Nacional Autónoma de México, Mexico City 04510, Mexico; (A.C.-G.); (J.R.-G.); (M.F.C.-H.)
| | - Jorge Reyes-García
- Departamento de Farmacología, Facultad de Medicina, Universidad Nacional Autónoma de México, Mexico City 04510, Mexico; (A.C.-G.); (J.R.-G.); (M.F.C.-H.)
| | - Verónica Díaz-Hernández
- Departamento de Embriología, Facultad de Medicina, Universidad Nacional Autónoma de México, Mexico City 04510, Mexico;
| | - María F. Casas-Hernández
- Departamento de Farmacología, Facultad de Medicina, Universidad Nacional Autónoma de México, Mexico City 04510, Mexico; (A.C.-G.); (J.R.-G.); (M.F.C.-H.)
| | - Francisco Javier Flores-Murrieta
- Unidad de Investigación en Farmacología, Instituto Nacional de Enfermedades Respiratorias Ismael Cosío Villegas, Mexico City 14080, Mexico;
- Sección de Estudios de Posgrado e Investigación, Escuela Superior de Medicina, Instituto Politécnico Nacional, Mexico City 11340, Mexico
| | - Luis M. Montaño
- Departamento de Farmacología, Facultad de Medicina, Universidad Nacional Autónoma de México, Mexico City 04510, Mexico; (A.C.-G.); (J.R.-G.); (M.F.C.-H.)
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2
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O'Grady SM, Kita H. ATP functions as a primary alarmin in allergen-induced type 2 immunity. Am J Physiol Cell Physiol 2023; 325:C1369-C1386. [PMID: 37842751 PMCID: PMC10861152 DOI: 10.1152/ajpcell.00370.2023] [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: 08/07/2023] [Revised: 10/09/2023] [Accepted: 10/09/2023] [Indexed: 10/17/2023]
Abstract
Environmental allergens that interact with the airway epithelium can activate cellular stress pathways that lead to the release of danger signals known as alarmins. The mechanisms of alarmin release are distinct from damage-associated molecular patterns (DAMPs), which typically escape from cells after loss of plasma membrane integrity. Oxidative stress represents a form of allergen-induced cellular stress that stimulates oxidant-sensing mechanisms coupled to pathways, which facilitate alarmin mobilization and efflux across the plasma membrane. In this review, we highlight examples of alarmin release and discuss their roles in the initiation of type 2 immunity and allergic airway inflammation. In addition, we discuss the concept of alarmin amplification, where "primary" alarmins, which are directly released in response to a specific cellular stress, stimulate additional signaling pathways that lead to secretion of "secondary" alarmins that include proinflammatory cytokines, such as IL-33, as well as genomic and mitochondrial DNA that coordinate or amplify type 2 immunity. Accordingly, allergen-evoked cellular stress can elicit a hierarchy of alarmin signaling responses from the airway epithelium that trigger local innate immune reactions, impact adaptive immunity, and exacerbate diseases including asthma and other chronic inflammatory conditions that affect airway function.
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Affiliation(s)
- Scott M O'Grady
- Department of Animal Science, University of Minnesota, St. Paul, Minnesota, United States
- Department of Integrative Biology and Physiology, University of Minnesota, Minneapolis, Minnesota, United States
| | - Hirohito Kita
- Division of Allergy, Asthma and Immunology, Mayo Clinic, Scottsdale, Arizona, United States
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3
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Schulman ES, Nishi H, Pelleg A. Degranulation of human mast cells: modulation by P2 receptors' agonists. Front Immunol 2023; 14:1216580. [PMID: 37868982 PMCID: PMC10585249 DOI: 10.3389/fimmu.2023.1216580] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Accepted: 09/04/2023] [Indexed: 10/24/2023] Open
Abstract
Since the late 1970s, there has been an alarming increase in the incidence of asthma and its morbidity and mortality. Acute obstruction and inflammation of allergic asthmatic airways are frequently caused by inhalation of exogenous substances such as allergens cross-linking IgE receptors expressed on the surface of the human lung mast cells (HLMC). The degree of constriction of human airways produced by identical amounts of inhaled allergens may vary from day to day and even hour to hour. Endogenous factors in the human mast cell (HMC)'s microenvironment during allergen exposure may markedly modulate the degranulation response. An increase in allergic responsiveness may significantly enhance bronchoconstriction and breathlessness. This review focuses on the role that the ubiquitous endogenous purine nucleotide, extracellular adenosine 5'-triphosphate (ATP), which is a component of the damage-associated molecular patterns, plays in mast cells' physiology. ATP activates P2 purinergic cell-surface receptors (P2R) to trigger signaling cascades resulting in heightened inflammatory responses. ATP is the most potent enhancer of IgE-mediated HLMC degranulation described to date. Current knowledge of ATP as it relates to targeted receptor(s) on HMC along with most recent studies exploring HMC post-receptor activation pathways are discussed. In addition, the reviewed studies may explain why brief, minimal exposures to allergens (e.g., dust, cat, mouse, and grass) can unpredictably lead to intense clinical reactions. Furthermore, potential therapeutic approaches targeting ATP-related enhancement of allergic reactions are presented.
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Affiliation(s)
- Edward S. Schulman
- Division of Pulmonary, Critical Care and Allergy, Drexel University College of Medicine, Philadelphia, PA, United States
| | - Haruhisa Nishi
- Department of Pharmacology, Jikei University School of Medicine, Tokyo, Japan
| | - Amir Pelleg
- Danmir Therapeutics, LLC, Haverford, PA, United States
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4
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Cai Y, Folkerts G, Braber S. Non-Digestible Oligosaccharides: A Novel Treatment for Respiratory Infections? Nutrients 2022; 14:nu14235033. [PMID: 36501062 PMCID: PMC9736878 DOI: 10.3390/nu14235033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2022] [Revised: 11/23/2022] [Accepted: 11/24/2022] [Indexed: 11/29/2022] Open
Abstract
Emerging antimicrobial resistance in respiratory infections requires novel intervention strategies. Non-digestible oligosaccharides (NDOs) are a diverse group of carbohydrates with broad protective effects. In addition to promoting the colonization of beneficial gut microbiota and maintaining the intestinal homeostasis, NDOs act as decoy receptors, effectively blocking the attachment of pathogens on host cells. NDOs also function as a bacteriostatic agent, inhibiting the growth of specific pathogenic bacteria. Based on this fact, NDOs potentiate the actions of antimicrobial drugs. Therefore, there is an increasing interest in characterizing the anti-infective properties of NDOs. This focused review provides insights into the mechanisms by which representative NDOs may suppress respiratory infections by targeting pathogens and host cells. We summarized the most interesting mechanisms of NDOs, including maintenance of gut microbiota homeostasis, interference with TLR-mediated signaling, anti-oxidative effects and bacterial toxin neutralization, bacteriostatic and bactericidal effects, and anti-adhesion or anti-invasive properties. A detailed understanding of anti-infective mechanisms of NDOs against respiratory pathogens may contribute to the development of add-on therapy or alternatives to antimicrobials.
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Affiliation(s)
- Yang Cai
- Department of Pharmacology, School of Medicine, Southeast University, Nanjing 210009, China
- Correspondence: (Y.C.); (S.B.)
| | - Gert Folkerts
- Division of Pharmacology, Utrecht Institute for Pharmaceutical Sciences, Faculty of Science, Utrecht University, 3584 CG Utrecht, The Netherlands
| | - Saskia Braber
- Division of Pharmacology, Utrecht Institute for Pharmaceutical Sciences, Faculty of Science, Utrecht University, 3584 CG Utrecht, The Netherlands
- Correspondence: (Y.C.); (S.B.)
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5
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Singanayagam A, Footitt J, Marczynski M, Radicioni G, Cross MT, Finney LJ, Trujillo-Torralbo MB, Calderazzo M, Zhu J, Aniscenko J, Clarke TB, Molyneaux PL, Bartlett NW, Moffatt MF, Cookson WO, Wedzicha J, Evans CM, Boucher RC, Kesimer M, Lieleg O, Mallia P, Johnston SL. Airway mucins promote immunopathology in virus-exacerbated chronic obstructive pulmonary disease. J Clin Invest 2022; 132:e120901. [PMID: 35239513 PMCID: PMC9012283 DOI: 10.1172/jci120901] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Accepted: 03/01/2022] [Indexed: 11/18/2022] Open
Abstract
The respiratory tract surface is protected from inhaled pathogens by a secreted layer of mucus rich in mucin glycoproteins. Abnormal mucus accumulation is a cardinal feature of chronic respiratory diseases, but the relationship between mucus and pathogens during exacerbations is poorly understood. We identified elevations in airway mucin 5AC (MUC5AC) and MUC5B concentrations during spontaneous and experimentally induced chronic obstructive pulmonary disease (COPD) exacerbations. MUC5AC was more sensitive to changes in expression during exacerbation and was therefore more predictably associated with viral load, inflammation, symptom severity, decrements in lung function, and secondary bacterial infections. MUC5AC was functionally related to inflammation, as Muc5ac-deficient (Muc5ac-/-) mice had attenuated RV-induced (RV-induced) airway inflammation, and exogenous MUC5AC glycoprotein administration augmented inflammatory responses and increased the release of extracellular adenosine triphosphate (ATP) in mice and human airway epithelial cell cultures. Hydrolysis of ATP suppressed MUC5AC augmentation of RV-induced inflammation in mice. Therapeutic suppression of mucin production using an EGFR antagonist ameliorated immunopathology in a mouse COPD exacerbation model. The coordinated virus induction of MUC5AC and MUC5B expression suggests that non-Th2 mechanisms trigger mucin hypersecretion during exacerbations. Our data identified a proinflammatory role for MUC5AC during viral infection and suggest that MUC5AC inhibition may ameliorate COPD exacerbations.
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Affiliation(s)
- Aran Singanayagam
- National Heart and Lung Institute, Imperial College London, London, United Kingdom
- Centre for Molecular Bacteriology and Infection, Imperial College London, London, United Kingdom
| | - Joseph Footitt
- National Heart and Lung Institute, Imperial College London, London, United Kingdom
| | - Matthias Marczynski
- School of Engineering and Design, Department of Materials Engineering and
- Center for Protein Assemblies, Technical University of Munich, Munich, Germany
| | - Giorgia Radicioni
- Marsico Lung Institute/Cystic Fibrosis and Pulmonary Research Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Michael T. Cross
- Division of Pulmonary Sciences and Critical Care Medicine, University of Colorado, Anschutz Medical Campus, Aurora, Colorado, USA
| | - Lydia J. Finney
- National Heart and Lung Institute, Imperial College London, London, United Kingdom
| | | | - Maria Calderazzo
- National Heart and Lung Institute, Imperial College London, London, United Kingdom
| | - Jie Zhu
- National Heart and Lung Institute, Imperial College London, London, United Kingdom
| | - Julia Aniscenko
- National Heart and Lung Institute, Imperial College London, London, United Kingdom
| | - Thomas B. Clarke
- Centre for Molecular Bacteriology and Infection, Imperial College London, London, United Kingdom
| | - Philip L. Molyneaux
- National Heart and Lung Institute, Imperial College London, London, United Kingdom
| | - Nathan W. Bartlett
- National Heart and Lung Institute, Imperial College London, London, United Kingdom
- College of Health, Medicine and Wellbeing, Hunter Medical Research Institute and University of Newcastle, Newcastle, New South Wales, Australia
| | - Miriam F. Moffatt
- National Heart and Lung Institute, Imperial College London, London, United Kingdom
| | - William O. Cookson
- National Heart and Lung Institute, Imperial College London, London, United Kingdom
| | - Jadwiga Wedzicha
- National Heart and Lung Institute, Imperial College London, London, United Kingdom
| | - Christopher M. Evans
- Division of Pulmonary Sciences and Critical Care Medicine, University of Colorado, Anschutz Medical Campus, Aurora, Colorado, USA
| | - Richard C. Boucher
- Marsico Lung Institute/Cystic Fibrosis and Pulmonary Research Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Mehmet Kesimer
- Marsico Lung Institute/Cystic Fibrosis and Pulmonary Research Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Oliver Lieleg
- School of Engineering and Design, Department of Materials Engineering and
- Center for Protein Assemblies, Technical University of Munich, Munich, Germany
| | - Patrick Mallia
- National Heart and Lung Institute, Imperial College London, London, United Kingdom
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6
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Hasan D, Shono A, van Kalken CK, van der Spek PJ, Krenning EP, Kotani T. A novel definition and treatment of hyperinflammation in COVID-19 based on purinergic signalling. Purinergic Signal 2021; 18:13-59. [PMID: 34757513 PMCID: PMC8578920 DOI: 10.1007/s11302-021-09814-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Accepted: 07/18/2021] [Indexed: 12/15/2022] Open
Abstract
Hyperinflammation plays an important role in severe and critical COVID-19. Using inconsistent criteria, many researchers define hyperinflammation as a form of very severe inflammation with cytokine storm. Therefore, COVID-19 patients are treated with anti-inflammatory drugs. These drugs appear to be less efficacious than expected and are sometimes accompanied by serious adverse effects. SARS-CoV-2 promotes cellular ATP release. Increased levels of extracellular ATP activate the purinergic receptors of the immune cells initiating the physiologic pro-inflammatory immune response. Persisting viral infection drives the ATP release even further leading to the activation of the P2X7 purinergic receptors (P2X7Rs) and a severe yet physiologic inflammation. Disease progression promotes prolonged vigorous activation of the P2X7R causing cell death and uncontrolled ATP release leading to cytokine storm and desensitisation of all other purinergic receptors of the immune cells. This results in immune paralysis with co-infections or secondary infections. We refer to this pathologic condition as hyperinflammation. The readily available and affordable P2X7R antagonist lidocaine can abrogate hyperinflammation and restore the normal immune function. The issue is that the half-maximal effective concentration for P2X7R inhibition of lidocaine is much higher than the maximal tolerable plasma concentration where adverse effects start to develop. To overcome this, we selectively inhibit the P2X7Rs of the immune cells of the lymphatic system inducing clonal expansion of Tregs in local lymph nodes. Subsequently, these Tregs migrate throughout the body exerting anti-inflammatory activities suppressing systemic and (distant) local hyperinflammation. We illustrate this with six critically ill COVID-19 patients treated with lidocaine.
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Affiliation(s)
| | - Atsuko Shono
- Department of Anaesthesiology and Critical Care Medicine, School of Medicine, Showa University, Tokyo, 142-8666, Japan
| | | | - Peter J van der Spek
- Department of Pathology & Clinical Bioinformatics, Erasmus MC, Erasmus Universiteit Rotterdam, 3015 CE, Rotterdam, The Netherlands
| | | | - Toru Kotani
- Department of Anaesthesiology and Critical Care Medicine, School of Medicine, Showa University, Tokyo, 142-8666, Japan
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7
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Kong X, Bennett WC, Jania CM, Chason KD, German Z, Adouli J, Budney SD, Oby BT, van Heusden C, Lazarowski ER, Jaspers I, Randell SH, Hedgespeth BA, Cruse G, Hua X, Schworer SA, Smith GJ, Kelada SN, Tilley SL. Identification of an ATP/P2X7/mast cell pathway mediating ozone-induced bronchial hyperresponsiveness. JCI Insight 2021; 6:140207. [PMID: 34546976 PMCID: PMC8663556 DOI: 10.1172/jci.insight.140207] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Accepted: 09/16/2021] [Indexed: 11/20/2022] Open
Abstract
Ozone is a highly reactive environmental pollutant with well-recognized adverse effects on lung health. Bronchial hyperresponsiveness (BHR) is one consequence of ozone exposure, particularly for individuals with underlying lung disease. Our data demonstrated that ozone induced substantial ATP release from human airway epithelia in vitro and into the airways of mice in vivo and that ATP served as a potent inducer of mast cell degranulation and BHR, acting through P2X7 receptors on mast cells. Both mast cell–deficient and P2X7 receptor–deficient (P2X7–/–) mice demonstrated markedly attenuated BHR to ozone. Reconstitution of mast cell–deficient mice with WT mast cells and P2X7–/– mast cells restored ozone-induced BHR. Despite equal numbers of mast cells in reconstituted mouse lungs, mice reconstituted with P2X7–/– mast cells demonstrated significantly less robust BHR than mice reconstituted with WT mast cells. These results support a model where P2X7 on mast cells and other cell types contribute to ozone-induced BHR.
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Affiliation(s)
- Xiaomei Kong
- Department of Respiratory and Critical Care Medicine, The First Hospital of Shanxi Medical University, Taiyuan, China
| | - William C Bennett
- Marsico Lung Institute and.,Division of Pulmonary Diseases and Critical Care Medicine, Department of Medicine, School of Medicine, University of North Carolina at Chapel Hill, North Carolina, USA
| | - Corey M Jania
- Marsico Lung Institute and.,Division of Pulmonary Diseases and Critical Care Medicine, Department of Medicine, School of Medicine, University of North Carolina at Chapel Hill, North Carolina, USA
| | - Kelly D Chason
- Marsico Lung Institute and.,Division of Pulmonary Diseases and Critical Care Medicine, Department of Medicine, School of Medicine, University of North Carolina at Chapel Hill, North Carolina, USA
| | - Zachary German
- Marsico Lung Institute and.,Wake Forest School of Medicine, Winston-Salem, North Carolina, USA
| | - Jennifer Adouli
- Marsico Lung Institute and.,Division of Pulmonary Diseases and Critical Care Medicine, Department of Medicine, School of Medicine, University of North Carolina at Chapel Hill, North Carolina, USA
| | - Samuel D Budney
- Marsico Lung Institute and.,Division of Pulmonary Diseases and Critical Care Medicine, Department of Medicine, School of Medicine, University of North Carolina at Chapel Hill, North Carolina, USA
| | - Brandon T Oby
- Marsico Lung Institute and.,Division of Pulmonary Diseases and Critical Care Medicine, Department of Medicine, School of Medicine, University of North Carolina at Chapel Hill, North Carolina, USA
| | - Catharina van Heusden
- Marsico Lung Institute and.,Division of Pulmonary Diseases and Critical Care Medicine, Department of Medicine, School of Medicine, University of North Carolina at Chapel Hill, North Carolina, USA
| | - Eduardo R Lazarowski
- Marsico Lung Institute and.,Division of Pulmonary Diseases and Critical Care Medicine, Department of Medicine, School of Medicine, University of North Carolina at Chapel Hill, North Carolina, USA
| | - Ilona Jaspers
- Department of Pediatrics and Center for Environmental Medicine, Asthma, and Lung Biology and
| | - Scott H Randell
- Marsico Lung Institute and.,Department of Cell Biology and Physiology, School of Medicine, University of North Carolina at Chapel Hill, North Carolina, USA
| | - Barry A Hedgespeth
- Department of Molecular Biomedical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, North Carolina, USA
| | - Glenn Cruse
- Department of Molecular Biomedical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, North Carolina, USA
| | - Xiaoyang Hua
- Department of Head and Neck Surgery & Communication Sciences, Duke University School of Medicine, Durham, North Carolina, USA.,Department of Otolaryngology - Head and Neck Surgery, Carver College of Medicine, University of Iowa, Iowa City, Iowa, USA
| | - Stephen A Schworer
- Marsico Lung Institute and.,Division of Pulmonary Diseases and Critical Care Medicine, Department of Medicine, School of Medicine, University of North Carolina at Chapel Hill, North Carolina, USA.,Division of Allergy and Immunology, Department of Pediatrics, and
| | - Gregory J Smith
- Department of Genetics, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Samir Np Kelada
- Department of Genetics, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Stephen L Tilley
- Marsico Lung Institute and.,Division of Pulmonary Diseases and Critical Care Medicine, Department of Medicine, School of Medicine, University of North Carolina at Chapel Hill, North Carolina, USA
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8
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Arzola-Martínez L, Benavente R, Vega G, Ríos M, Fonseca W, Rasky AJ, Morris S, Lukacs NW, Villalón MJ. Blocking ATP-releasing channels prevents high extracellular ATP levels and airway hyperreactivity in an asthmatic mouse model. Am J Physiol Lung Cell Mol Physiol 2021; 321:L466-L476. [PMID: 34231389 DOI: 10.1152/ajplung.00450.2020] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Allergic asthma is a chronic airway inflammatory response to different triggers like inhaled allergens. Excessive ATP in fluids from patients with asthma is considered an inflammatory signal and an important autocrine/paracrine modulator of airway physiology. Here, we investigated the deleterious effect of increased extracellular ATP (eATP) concentration on the mucociliary clearance (MCC) effectiveness and determined the role of ATP releasing channels during airway inflammation in an ovalbumin (OVA)-sensitized mouse model. Our allergic mouse model exhibited high levels of eATP measured in the tracheal fluid with a luciferin-luciferase assay and reduced MCC velocity determined by microspheres tracking in the trachea ex vivo. Addition of ATP had a dual effect on MCC, where lower ATP concentration (µM) increased microspheres velocity, whereas higher concentration (mM) transiently stopped microspheres movement. Also, an augmented ethidium bromide uptake by the allergic tracheal airway epithelium suggests an increase in ATP release channel functionality during inflammatory conditions. The use of carbenoxolone, a nonspecific inhibitor of connexin and pannexin1 channels reduced the eATP concentration in the allergic mouse tracheal fluid and dye uptake by the airway epithelium, providing evidence that these ATP release channels are facilitating the net flux of ATP to the lumen during airway inflammation. However, only the specific inhibition of pannexin1 with 10Panx peptide significantly reduced eATP in bronchoalveolar lavage and decreased airway hyperresponsiveness in OVA-allergic mouse model. These data provide evidence that blocking eATP may be a pharmacological alternative to be explored in rescue therapy during episodes of airflow restriction in patients with asthma.
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Affiliation(s)
- Llilian Arzola-Martínez
- Department of Physiology, Faculty of Biological Science, Pontificia Universidad Católica de Chile, Santiago, Chile.,Department of Pathology, University of Michigan, Ann Arbor, Michigan
| | - Rebeca Benavente
- Department of Physiology, Faculty of Biological Science, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Génesis Vega
- Department of Physiology, Faculty of Biological Science, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Mariana Ríos
- Department of Molecular Genetics and Microbiology, Faculty of Biological Science, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Wendy Fonseca
- Department of Pathology, University of Michigan, Ann Arbor, Michigan
| | - Andrew J Rasky
- Department of Pathology, University of Michigan, Ann Arbor, Michigan
| | - Susan Morris
- Department of Pathology, University of Michigan, Ann Arbor, Michigan
| | - Nicholas W Lukacs
- Department of Pathology, University of Michigan, Ann Arbor, Michigan
| | - Manuel J Villalón
- Department of Physiology, Faculty of Biological Science, Pontificia Universidad Católica de Chile, Santiago, Chile
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9
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Airway Epithelial Nucleotide Release Contributes to Mucociliary Clearance. Life (Basel) 2021; 11:life11050430. [PMID: 34064654 PMCID: PMC8151306 DOI: 10.3390/life11050430] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Accepted: 04/28/2021] [Indexed: 12/18/2022] Open
Abstract
Mucociliary clearance (MCC) is a dominant component of pulmonary host defense. In health, the periciliary layer (PCL) is optimally hydrated, thus acting as an efficient lubricant layer over which the mucus layer moves by ciliary force. Airway surface dehydration and production of hyperconcentrated mucus is a common feature of chronic obstructive lung diseases such as cystic fibrosis (CF) and chronic bronchitis (CB). Mucus hydration is driven by electrolyte transport activities, which in turn are regulated by airway epithelial purinergic receptors. The activity of these receptors is controlled by the extracellular concentrations of ATP and its metabolite adenosine. Vesicular and conducted pathways contribute to ATP release from airway epithelial cells. In this study, we review the evidence leading to the identification of major components of these pathways: (a) the vesicular nucleotide transporter VNUT (the product of the SLC17A9 gene), the ATP transporter mediating ATP storage in (and release from) mucin granules and secretory vesicles; and (b) the ATP conduit pannexin 1 expressed in non-mucous airway epithelial cells. We further illustrate that ablation of pannexin 1 reduces, at least in part, airway surface liquid (ASL) volume production, ciliary beating, and MCC rates.
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10
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Lazarowski ER, Boucher RC. Purinergic receptors in airway hydration. Biochem Pharmacol 2021; 187:114387. [PMID: 33358825 DOI: 10.1016/j.bcp.2020.114387] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2020] [Revised: 12/16/2020] [Accepted: 12/17/2020] [Indexed: 02/08/2023]
Abstract
Airway epithelial purinergic receptors control key components of the mucociliary clearance (MCC), the dominant component of pulmonary host defense. In healthy airways, the periciliary liquid (PCL) is optimally hydrated, thus acting as an efficient lubricant layer over which the mucus layer moves by ciliary force. When the hydration of the airway surface decreases, the mucus becomes hyperconcentrated, the PCL collapses, and the "thickened" mucus layer adheres to cell surfaces, causing plaque/plug formation. Mucus accumulation is a major contributing factor to the progression of chronic obstructive lung diseases such as cystic fibrosis (CF) and chronic bronchitis (CB). Mucus hydration is regulated by finely tuned mechanisms of luminal Cl- secretion and Na+ absorption with concomitant osmotically driven water flow. These activities are regulated by airway surface liquid (ASL) concentrations of adenosine and ATP, acting on airway epithelial A2B and P2Y2 receptors, respectively. The goal of this article is to provide an overview of our understanding of the role of purinergic receptors in the regulation of airway epithelial ion/fluid transport and the mechanisms of nucleotide release and metabolic activities that contribute to airway surface hydration in healthy and chronically obstructed airways.
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Affiliation(s)
- Eduardo R Lazarowski
- Marsico Lung Institute/Cystic Fibrosis Center, School of Medicine, University of North Carolina, Chapel Hill, NC, United States.
| | - Richard C Boucher
- Marsico Lung Institute/Cystic Fibrosis Center, School of Medicine, University of North Carolina, Chapel Hill, NC, United States
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11
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van Heusden C, Button B, Anderson WH, Ceppe A, Morton LC, O'Neal WK, Dang H, Alexis NE, Donaldson S, Stephan H, Boucher RC, Lazarowski ER. Inhibition of ATP hydrolysis restores airway surface liquid production in cystic fibrosis airway epithelia. Am J Physiol Lung Cell Mol Physiol 2020; 318:L356-L365. [PMID: 31800264 PMCID: PMC7052677 DOI: 10.1152/ajplung.00449.2019] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Revised: 11/26/2019] [Accepted: 11/27/2019] [Indexed: 11/22/2022] Open
Abstract
Airway surface dehydration is a pathological feature of cystic fibrosis (CF) lung disease. CF is caused by mutations in the CF transmembrane conductance regulator (CFTR), a cyclic AMP-regulated Cl- channel controlled in part by the adenosine A2B receptor. An alternative CFTR-independent mechanism of fluid secretion is regulated by ATP via the P2Y2 receptor (P2Y2R) that activates Ca2+-regulated Cl- channels (CaCC/TMEM16) and inhibits Na+ absorption. However, due to rapid ATP hydrolysis, steady-state ATP levels in CF airway surface liquid (ASL) are inadequate to maintain P2Y2R-mediated fluid secretion. Therefore, inhibiting airway epithelial ecto-ATPases to increase ASL ATP levels constitutes a strategy to restore airway surface hydration in CF. Using [γ32P]ATP as radiotracer, we assessed the effect of a series of ATPase inhibitory compounds on the stability of physiologically occurring ATP concentrations. We identified the polyoxometalate [Co4(H2O)2(PW9O34)2]10- (POM-5) as the most potent and effective ecto-ATPase inhibitor in CF airway epithelial cells. POM-5 caused long-lasting inhibition of ATP hydrolysis in airway epithelia, which was reversible upon removal of the inhibitor. Importantly, POM-5 markedly enhanced steady-state levels of released ATP, promoting increased ASL volume in CF cell surfaces. These results provide proof of concept for ecto-ATPase inhibitors as therapeutic agents to restore hydration of CF airway surfaces. As a test of this notion, cell-free sputum supernatants from CF subjects were studied and found to have abnormally elevated ATPase activity, which was markedly inhibited by POM-5.
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Affiliation(s)
- Catharina van Heusden
- Marsico Lung Institute/UNC CF Research Center, University of North Carolina, Chapel Hill, North Carolina
| | - Brian Button
- Marsico Lung Institute/UNC CF Research Center, University of North Carolina, Chapel Hill, North Carolina
- Department of Biophysics and Biochemistry, University of North Carolina, Chapel Hill, North Carolina
| | - Wayne H Anderson
- Marsico Lung Institute/Pulmonary and Critical Care Medicine, University of North Carolina, Chapel Hill, North Carolina
| | - Agathe Ceppe
- Marsico Lung Institute/UNC CF Research Center, University of North Carolina, Chapel Hill, North Carolina
| | - Lisa C Morton
- Marsico Lung Institute/UNC CF Research Center, University of North Carolina, Chapel Hill, North Carolina
| | - Wanda K O'Neal
- Marsico Lung Institute/UNC CF Research Center, University of North Carolina, Chapel Hill, North Carolina
| | - Hong Dang
- Marsico Lung Institute/UNC CF Research Center, University of North Carolina, Chapel Hill, North Carolina
| | - Neil E Alexis
- Center for Environmental Medicine, Asthma and Lung Biology, University of North Carolina, Chapel Hill, North Carolina
| | - Scott Donaldson
- Marsico Lung Institute/UNC CF Research Center, University of North Carolina, Chapel Hill, North Carolina
| | - Holger Stephan
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiopharmaceutical Cancer Research, Dresden, Germany
| | - Richard C Boucher
- Marsico Lung Institute/UNC CF Research Center, University of North Carolina, Chapel Hill, North Carolina
| | - Eduardo R Lazarowski
- Marsico Lung Institute/UNC CF Research Center, University of North Carolina, Chapel Hill, North Carolina
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12
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Kilic O, Yoon A, Shah SR, Yong HM, Ruiz-Valls A, Chang H, Panettieri RA, Liggett SB, Quiñones-Hinojosa A, An SS, Levchenko A. A microphysiological model of the bronchial airways reveals the interplay of mechanical and biochemical signals in bronchospasm. Nat Biomed Eng 2019; 3:532-544. [PMID: 31150010 PMCID: PMC6653686 DOI: 10.1038/s41551-019-0366-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2017] [Accepted: 02/07/2019] [Indexed: 01/08/2023]
Abstract
In asthma, airway smooth muscle (ASM) contraction and the subsequent decrease in airflow involve a poorly understood set of mechanical and biochemical events. Organ-level and molecular-scale models of the airway are frequently based on purely mechanical or biochemical considerations and do not account for physiological mechanochemical couplings. Here, we present a microphysiological model of the airway that allows for the quantitative analysis of the interactions between mechanical and biochemical signals triggered by compressive stress on epithelial cells. We show that a mechanical stimulus mimicking a bronchospastic challenge triggers the marked contraction and delayed relaxation of ASM, and that this is mediated by the discordant expression of cyclooxygenase genes in epithelial cells and regulated by the mechanosensor and transcriptional co-activator YAP (Yes-associated protein). A mathematical model of the intercellular feedback interactions recapitulates aspects of obstructive disease of the airways, including pathognomonic features of severe, difficult-to-treat asthma. The microphysiological model could be used to investigate the mechanisms of asthma pathogenesis and to develop therapeutic strategies that disrupt the positive feedback loop that leads to persistent airway constriction.
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Affiliation(s)
- Onur Kilic
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, USA. .,Department of Environmental Health and Engineering, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA.
| | - Arum Yoon
- Department of Environmental Health and Engineering, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - Sagar R Shah
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, USA
| | - Hwan Mee Yong
- Department of Environmental Health and Engineering, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - Alejandro Ruiz-Valls
- Department of Neurosurgery, Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Hao Chang
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, USA
| | - Reynold A Panettieri
- Institute for Translational Medicine and Science, Rutgers University, New Brunswick, NJ, USA
| | - Stephen B Liggett
- Department of Medical Engineering, University of South Florida, Tampa, FL, USA.,Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL, USA
| | | | - Steven S An
- Department of Environmental Health and Engineering, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA. .,Department of Biochemistry and Molecular Biology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA. .,Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, MD, USA. .,Department of Biomedical Engineering, Ulsan National Institute of Science and Technology, Ulsan, Republic of Korea.
| | - Andre Levchenko
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, USA. .,Department of Biomedical Engineering, Yale University, New Haven, CT, USA. .,Yale Systems Biology Institute, Yale University, West Haven, CT, USA.
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13
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Winkelmann VE, Thompson KE, Neuland K, Jaramillo AM, Fois G, Schmidt H, Wittekindt OH, Han W, Tuvim MJ, Dickey BF, Dietl P, Frick M. Inflammation-induced upregulation of P2X 4 expression augments mucin secretion in airway epithelia. Am J Physiol Lung Cell Mol Physiol 2018; 316:L58-L70. [PMID: 30358443 DOI: 10.1152/ajplung.00157.2018] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Mucus clearance provides an essential innate defense mechanism to keep the airways and lungs free of particles and pathogens. Baseline and stimulated mucin secretion from secretory airway epithelial cells need to be tightly regulated to prevent mucus hypersecretion and mucus plugging of the airways. It is well established that extracellular ATP is a potent stimulus for regulated mucus secretion. Previous studies revealed that ATP acts via metabotropic P2Y2 purinoreceptors on goblet cells. Extracellular ATP, however, is also a potent agonist for ionotropic P2X purinoreceptors. Expression of several P2X isoforms has been reported in airways, but cell type-specific expression and the function thereof remained elusive. With this study, we now provide evidence that P2X4 is the predominant P2X isoform expressed in secretory airway epithelial cells. After IL-13 treatment of either human primary tracheal epithelial cells or mice, P2X4 expression is upregulated in vitro and in vivo under conditions of chronic inflammation, mucous metaplasia, and hyperplasia. Upregulation of P2X4 is strongest in MUC5AC-positive goblet cells. Moreover, activation of P2X4 by extracellular ATP augments intracellular Ca2+ signals and mucin secretion, whereas Ca2+ signals and mucin secretion are dampened by inhibition of P2X4 receptors. These data provide new insights into the purinergic regulation of mucin secretion and add to the emerging picture that P2X receptors modulate exocytosis of large secretory organelles and secretion of macromolecular vesicle cargo.
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Affiliation(s)
| | - Kristin E Thompson
- Centre de Recherche Saint-Antoine, INSERM, Université Pierre et Marie Curie-Université Paris 06, Sorbonne Universités, Paris , France
| | - Kathrin Neuland
- Institute of General Physiology, Ulm University , Ulm , Germany
| | - Ana M Jaramillo
- Department of Pulmonary Medicine, MD Anderson Cancer Center , Houston, Texas
| | - Giorgio Fois
- Institute of General Physiology, Ulm University , Ulm , Germany
| | - Hanna Schmidt
- Institute of General Physiology, Ulm University , Ulm , Germany
| | | | - Wei Han
- Department of Pulmonary Medicine, MD Anderson Cancer Center , Houston, Texas
| | - Michael J Tuvim
- Department of Pulmonary Medicine, MD Anderson Cancer Center , Houston, Texas
| | - Burton F Dickey
- Department of Pulmonary Medicine, MD Anderson Cancer Center , Houston, Texas
| | - Paul Dietl
- Institute of General Physiology, Ulm University , Ulm , Germany
| | - Manfred Frick
- Institute of General Physiology, Ulm University , Ulm , Germany
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14
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Hahn A, Salomon JJ, Leitz D, Feigenbutz D, Korsch L, Lisewski I, Schrimpf K, Millar-Büchner P, Mall MA, Frings S, Möhrlen F. Expression and function of Anoctamin 1/TMEM16A calcium-activated chloride channels in airways of in vivo mouse models for cystic fibrosis research. Pflugers Arch 2018; 470:1335-1348. [DOI: 10.1007/s00424-018-2160-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Revised: 04/30/2018] [Accepted: 05/23/2018] [Indexed: 01/17/2023]
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15
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Beckel JM, Gómez NM, Lu W, Campagno KE, Nabet B, Albalawi F, Lim JC, Boesze-Battaglia K, Mitchell CH. Stimulation of TLR3 triggers release of lysosomal ATP in astrocytes and epithelial cells that requires TRPML1 channels. Sci Rep 2018; 8:5726. [PMID: 29636491 PMCID: PMC5893592 DOI: 10.1038/s41598-018-23877-3] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Accepted: 03/16/2018] [Indexed: 01/25/2023] Open
Abstract
Cross-reactions between innate immunity, lysosomal function, and purinergic pathways may link signaling systems in cellular pathologies. We found activation of toll-like receptor 3 (TLR3) triggers lysosomal ATP release from both astrocytes and retinal pigmented epithelial (RPE) cells. ATP efflux was accompanied by lysosomal acid phosphatase and beta hexosaminidase release. Poly(I:C) alkalinized lysosomes, and lysosomal alkalization with bafilomycin or chloroquine triggered ATP release. Lysosomal rupture with glycyl-L-phenylalanine-2-naphthylamide (GPN) eliminated both ATP and acid phosphatase release. Secretory lysosome marker LAMP3 colocalized with VNUT, while MANT-ATP colocalized with LysoTracker. Unmodified membrane-impermeant 21-nt and "non-targeting" scrambled 21-nt siRNA triggered ATP and acid phosphatase release, while smaller 16-nt RNA was ineffective. Poly(I:C)-dependent ATP release was reduced by TBK-1 block and in TRPML1-/- cells, while TRPML activation with ML-SA1 was sufficient to release both ATP and acid phosphatase. The ability of poly(I:C) to raise cytoplasmic Ca2+ was abolished by removing extracellular ATP with apyrase, suggesting ATP release by poly(I:C) increased cellular signaling. Starvation but not rapamycin prevented lysosomal ATP release. In summary, stimulation of TLR3 triggers lysosomal alkalization and release of lysosomal ATP through activation of TRPML1; this links innate immunity to purinergic signaling via lysosomal physiology, and suggests even scrambled siRNA can influence these pathways.
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Affiliation(s)
- Jonathan M Beckel
- Department of Anatomy and Cell Biology, University of Pennsylvania, Philadelphia, PA, USA
- Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Néstor Más Gómez
- Department of Anatomy and Cell Biology, University of Pennsylvania, Philadelphia, PA, USA
| | - Wennan Lu
- Department of Anatomy and Cell Biology, University of Pennsylvania, Philadelphia, PA, USA
| | - Keith E Campagno
- Department of Anatomy and Cell Biology, University of Pennsylvania, Philadelphia, PA, USA
| | - Bardia Nabet
- Department of Anatomy and Cell Biology, University of Pennsylvania, Philadelphia, PA, USA
| | - Farraj Albalawi
- Department of Anatomy and Cell Biology, University of Pennsylvania, Philadelphia, PA, USA
- Department of Orthodontics, University of Pennsylvania, Philadelphia, PA, USA
| | - Jason C Lim
- Department of Anatomy and Cell Biology, University of Pennsylvania, Philadelphia, PA, USA
| | | | - Claire H Mitchell
- Department of Anatomy and Cell Biology, University of Pennsylvania, Philadelphia, PA, USA.
- Department of Ophthalmology, University of Pennsylvania, Philadelphia, PA, USA.
- Department of Physiology, University of Pennsylvania, Philadelphia, PA, USA.
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16
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Abdullah LH, Coakley R, Webster MJ, Zhu Y, Tarran R, Radicioni G, Kesimer M, Boucher RC, Davis CW, Ribeiro CMP. Mucin Production and Hydration Responses to Mucopurulent Materials in Normal versus Cystic Fibrosis Airway Epithelia. Am J Respir Crit Care Med 2018; 197:481-491. [PMID: 29099608 PMCID: PMC5821906 DOI: 10.1164/rccm.201706-1139oc] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Accepted: 11/03/2017] [Indexed: 01/01/2023] Open
Abstract
RATIONALE Cystic fibrosis (CF) airways disease produces a mucoobstructive lung phenotype characterized by airways mucus plugging, epithelial mucous cell metaplasia/hyperplasia, chronic infection, and inflammation. Simultaneous biochemical and functional in vivo studies of mucin synthesis and secretion from CF airways are not available. In vitro translational models may quantitate differential CF versus normal mucin and fluid secretory responses to infectious/inflammatory stimuli. OBJECTIVES We tested the hypothesis that CF airways exhibit defective epithelial fluid, but not mucin, secretory responses to bacterial/inflammatory host products. METHODS Well-differentiated primary human bronchial epithelial cultures were exposed to supernatant from mucopurulent material (SMM) from human CF airways as a test of bacterial/inflammatory host product stimulus. Human bronchial epithelia (HBE) with normal CF transmembrane conductance regulator function were compared with ΔF508/ΔF508 CF HBE. MEASUREMENTS AND MAIN RESULTS Acute (up to 60 min) SMM exposure promoted mucin secretion, but mucins were degraded by the proteolytic enzymes present in SMM. Chronic SMM exposure induced upregulation of mucin synthesis and storage and generated absolute increases in basal and stimulated mucin release in normal and CF cultures. These responses were similar in normal and CF cultures. In contrast, SMM produced a coordinated CF transmembrane conductance regulator-mediated Cl- secretory response in normal HBE, but not in CF HBE. The absence of the fluid secretory response in CF produced quantitatively more dehydrated mucus. CONCLUSIONS Our study reveals the interplay between regulation of mucin and fluid secretion rates in inflamed versus noninflamed conditions and why a hyperconcentrated mucus is produced in CF airways.
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Affiliation(s)
| | - Raymond Coakley
- Marsico Lung Institute and Cystic Fibrosis Research Center
- Department of Medicine
| | | | - Yunxiang Zhu
- Marsico Lung Institute and Cystic Fibrosis Research Center
| | - Robert Tarran
- Marsico Lung Institute and Cystic Fibrosis Research Center
- Department of Cell Biology and Physiology, and
| | | | - Mehmet Kesimer
- Marsico Lung Institute and Cystic Fibrosis Research Center
- Department of Pathology and Laboratory Medicine, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Richard C. Boucher
- Marsico Lung Institute and Cystic Fibrosis Research Center
- Department of Medicine
| | - C. William Davis
- Marsico Lung Institute and Cystic Fibrosis Research Center
- Department of Cell Biology and Physiology, and
| | - Carla M. P. Ribeiro
- Marsico Lung Institute and Cystic Fibrosis Research Center
- Department of Medicine
- Department of Cell Biology and Physiology, and
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17
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Potential contribution of alveolar epithelial type I cells to pulmonary fibrosis. Biosci Rep 2017; 37:BSR20171301. [PMID: 29026006 PMCID: PMC5696455 DOI: 10.1042/bsr20171301] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Revised: 09/28/2017] [Accepted: 09/29/2017] [Indexed: 12/13/2022] Open
Abstract
Pulmonary fibrosis (PF) is characterized by inflammation and fibrosis of the interstitium and destruction of alveolar histoarchitecture ultimately leading to a fatal impairment of lung function. Different concepts describe either a dominant role of inflammatory pathways or a disturbed remodeling of resident cells of the lung parenchyma during fibrogenesis. Further, a combination of both the mechanisms has been postulated. The present review emphasizes the particular involvement of alveolar epithelial type I cells in all these processes, their contribution to innate immune/inflammatory functions and maintenance of proper alveolar barrier functions. Amongst the different inflammatory and repair events the purinergic receptor P2X7, an ATP-gated cationic channel that regulates not only apoptosis, necrosis, autophagy, and NLPR3 inflammosome activation, but also the turnover of diverse tight junction (TJ) and water channel proteins, seems to be essential for the stability of alveolar barrier integrity and for the interaction with protective factors during lung injury.
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18
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Takahashi K, Ito S, Furuya K, Asano S, Sokabe M, Hasegawa Y. Real-time imaging of mechanically and chemically induced ATP release in human lung fibroblasts. Respir Physiol Neurobiol 2017; 242:96-101. [PMID: 28442443 DOI: 10.1016/j.resp.2017.04.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2017] [Revised: 04/19/2017] [Accepted: 04/19/2017] [Indexed: 12/26/2022]
Abstract
Extracellular adenosine 5'-triphosphate (ATP) acts as an inflammatory mediator of pulmonary fibrosis. We investigated the effects of mechanical and chemical stimuli on ATP release from primary normal human lung fibroblasts. We visualized the ATP release from fibroblasts in real time using a luminescence imaging system while acquiring differential interference contrast cell images with infrared optics. Immediately following a single uniaxial stretch for 1s, ATP was released from a certain population of cells and spread to surrounding spaces. Hypotonic stress, which causes plasma membrane stretching, also induced the ATP release. Compared with the effects of mechanical stretch, ATP-induced release sites were homogeneously distributed. In contrast to the effects of mechanical stimuli, application of platelet-derived growth factor caused ATP release from small numbers of the cells. Our real-time ATP imaging demonstrates that there is a heterogeneous nature of ATP release from lung fibroblasts in response to mechanical and chemical stimuli.
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Affiliation(s)
- Kota Takahashi
- Department of Respiratory Medicine, Nagoya University Graduate School of Medicine, Nagoya 466-8550, Japan
| | - Satoru Ito
- Department of Respiratory Medicine, Nagoya University Graduate School of Medicine, Nagoya 466-8550, Japan; Department of Respiratory Medicine and Allergology, Aichi Medical University, Nagakute 480-1195, Japan.
| | - Kishio Furuya
- Mechanobiology Laboratory, Nagoya University Graduate School of Medicine, Nagoya 466-8550, Japan
| | - Shuichi Asano
- Department of Respiratory Medicine, Nagoya University Graduate School of Medicine, Nagoya 466-8550, Japan
| | - Masahiro Sokabe
- Mechanobiology Laboratory, Nagoya University Graduate School of Medicine, Nagoya 466-8550, Japan
| | - Yoshinori Hasegawa
- Department of Respiratory Medicine, Nagoya University Graduate School of Medicine, Nagoya 466-8550, Japan
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19
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Broeren MGA, de Vries M, Bennink MB, van Lent PLEM, van der Kraan PM, Koenders MI, Thurlings RM, van de Loo FAJ. Functional Tissue Analysis Reveals Successful Cryopreservation of Human Osteoarthritic Synovium. PLoS One 2016; 11:e0167076. [PMID: 27870898 PMCID: PMC5117761 DOI: 10.1371/journal.pone.0167076] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2016] [Accepted: 11/08/2016] [Indexed: 12/29/2022] Open
Abstract
Osteoarthritis (OA) is a degenerative joint disease affecting cartilage and is the most common form of arthritis worldwide. One third of OA patients have severe synovitis and less than 10% have no evidence of synovitis. Moreover, synovitis is predictive for more severe disease progression. This offers a target for therapy but more research on the pathophysiological processes in the synovial tissue of these patients is needed. Functional studies performed with synovial tissue will be more approachable when this material, that becomes available by joint replacement surgery, can be stored for later use. We set out to determine the consequences of slow-freezing of human OA synovial tissue. Therefore, we validated a method that can be applied in every routine laboratory and performed a comparative study of five cryoprotective agent (CPA) solutions. To determine possible deleterious cryopreservation-thaw effects on viability, the synovial tissue architecture, metabolic activity, RNA quality, expression of cryopreservation associated stress genes, and expression of OA characteristic disease genes was studied. Furthermore, the biological activity of the cryopreserved tissue was determined by measuring cytokine secretion induced by the TLR ligands lipopolysaccharides and Pam3Cys. Compared to non frozen synovium, no difference in cell and tissue morphology could be identified in the conditions using the CS10, standard and CryoSFM CPA solution for cryopreservation. However, we observed significantly lower preservation of tissue morphology with the Biofreeze and CS2 media. The other viability assays showed trends in the same direction but were not sensitive enough to detect significant differences between conditions. In all assays tested a clearly lower viability was detected in the condition in which synovium was frozen without CPA solution. This detailed analysis showed that OA synovial tissue explants can be cryopreserved while maintaining the morphology, viability and phenotypical response after thawing, offering enhanced opportunities for human in vitro studies.
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Affiliation(s)
- Mathijs G. A. Broeren
- Experimental Rheumatology, Department of Rheumatology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Marieke de Vries
- Experimental Rheumatology, Department of Rheumatology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Miranda B. Bennink
- Experimental Rheumatology, Department of Rheumatology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Peter L. E. M. van Lent
- Experimental Rheumatology, Department of Rheumatology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Peter M. van der Kraan
- Experimental Rheumatology, Department of Rheumatology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Marije I. Koenders
- Experimental Rheumatology, Department of Rheumatology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Rogier M. Thurlings
- Experimental Rheumatology, Department of Rheumatology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Fons A. J. van de Loo
- Experimental Rheumatology, Department of Rheumatology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, the Netherlands
- * E-mail:
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20
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Urothelial ATP exocytosis: regulation of bladder compliance in the urine storage phase. Sci Rep 2016; 6:29761. [PMID: 27412485 PMCID: PMC4944198 DOI: 10.1038/srep29761] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Accepted: 06/24/2016] [Indexed: 12/30/2022] Open
Abstract
The bladder urothelium is more than just a barrier. When the bladder is distended, the urothelium functions as a sensor to initiate the voiding reflex, during which it releases ATP via multiple mechanisms. However, the mechanisms underlying this ATP release in response to the various stretch stimuli caused by bladder filling remain largely unknown. Therefore, the aim of this study was to elucidate these mechanisms. By comparing vesicular nucleotide transporter (VNUT)-deficient and wild-type male mice, we showed that ATP has a crucial role in urine storage through exocytosis via a VNUT-dependent mechanism. VNUT was abundantly expressed in the bladder urothelium, and when the urothelium was weakly stimulated (i.e. in the early filling stages), it released ATP by exocytosis. VNUT-deficient mice showed reduced bladder compliance from the early storage phase and displayed frequent urination in inappropriate places without a change in voiding function. We conclude that urothelial, VNUT-dependent ATP exocytosis is involved in urine storage mechanisms that promote the relaxation of the bladder during the early stages of filling.
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21
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Cogliati B, Mennecier G, Willebrords J, Da Silva TC, Maes M, Pereira IVA, Crespo-Yanguas S, Hernandez-Blazquez FJ, Dagli MLZ, Vinken M. Connexins, Pannexins, and Their Channels in Fibroproliferative Diseases. J Membr Biol 2016; 249:199-213. [PMID: 26914707 DOI: 10.1007/s00232-016-9881-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2015] [Accepted: 02/16/2016] [Indexed: 12/13/2022]
Abstract
Cellular and molecular mechanisms of wound healing, tissue repair, and fibrogenesis are established in different organs and are essential for the maintenance of function and tissue integrity after cell injury. These mechanisms are also involved in a plethora of fibroproliferative diseases or organ-specific fibrotic disorders, all of which are associated with the excessive deposition of extracellular matrix components. Fibroblasts, which are key cells in tissue repair and fibrogenesis, rely on communicative cellular networks to ensure efficient control of these processes and to prevent abnormal accumulation of extracellular matrix into the tissue. Despite the significant impact on human health, and thus the epidemiologic relevance, there is still no effective treatment for most fibrosis-related diseases. This paper provides an overview of current concepts and mechanisms involved in the participation of cellular communication via connexin-based pores as well as pannexin-based channels in the processes of tissue repair and fibrogenesis in chronic diseases. Understanding these mechanisms may contribute to the development of new therapeutic strategies to clinically manage fibroproliferative diseases and organ-specific fibrotic disorders.
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Affiliation(s)
- Bruno Cogliati
- Department of Pathology, School of Veterinary Medicine and Animal Science, University of São Paulo, Brazil
| | - Gregory Mennecier
- Department of Pathology, School of Veterinary Medicine and Animal Science, University of São Paulo, Brazil
| | - Joost Willebrords
- Department of In Vitro Toxicology and Dermato-Cosmetology, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel, Brussels, Belgium
| | - Tereza Cristina Da Silva
- Department of Pathology, School of Veterinary Medicine and Animal Science, University of São Paulo, Brazil
| | - Michaël Maes
- Department of In Vitro Toxicology and Dermato-Cosmetology, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel, Brussels, Belgium
| | | | - Sara Crespo-Yanguas
- Department of In Vitro Toxicology and Dermato-Cosmetology, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel, Brussels, Belgium
| | | | - Maria Lúcia Zaidan Dagli
- Department of Pathology, School of Veterinary Medicine and Animal Science, University of São Paulo, Brazil
| | - Mathieu Vinken
- Department of In Vitro Toxicology and Dermato-Cosmetology, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel, Brussels, Belgium
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22
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Ito S, Furuya K, Sokabe M, Hasegawa Y. Cellular ATP release in the lung and airway. AIMS BIOPHYSICS 2016. [DOI: 10.3934/biophy.2016.4.571] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
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Baseline Goblet Cell Mucin Secretion in the Airways Exceeds Stimulated Secretion over Extended Time Periods, and Is Sensitive to Shear Stress and Intracellular Mucin Stores. PLoS One 2015; 10:e0127267. [PMID: 26024524 PMCID: PMC4449158 DOI: 10.1371/journal.pone.0127267] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2015] [Accepted: 04/13/2015] [Indexed: 12/22/2022] Open
Abstract
Airway mucin secretion studies have focused on goblet cell responses to exogenous agonists almost to the exclusion of baseline mucin secretion (BLMS). In human bronchial epithelial cell cultures (HBECCs), maximal agonist-stimulated secretion exceeds baseline by ~3-fold as measured over hour-long periods, but mucin stores are discharged completely and require 24 h for full restoration. Hence, over 24 h, total baseline exceeds agonist-induced secretion by several-fold. Studies with HBECCs and mouse tracheas showed that BLMS is highly sensitive to mechanical stresses. Harvesting three consecutive 1 h baseline luminal incubations with HBECCs yielded equal rates of BLMS; however, lengthening the middle period to 72 h decreased the respective rate significantly, suggesting a stimulation of BLMS by the gentle washes of HBECC luminal surfaces. BLMS declined exponentially after washing HBECCs (t1/2 = 2.75 h), to rates approaching zero. HBECCs exposed to low perfusion rates exhibited spike-like increases in BLMS when flow was jumped 5-fold: BLMS increased >4 fold, then decreased within 5 min to a stable plateau at 1.5–2-fold over control. Higher flow jumps induced proportionally higher BLMS increases. Inducing mucous hyperplasia in HBECCs increased mucin production, BLMS and agonist-induced secretion. Mouse tracheal BLMS was ~6-fold higher during perfusion, than when flow was stopped. Munc13-2 null mouse tracheas, with their defect of accumulated cellular mucins, exhibited similar BLMS as WT, contrary to predictions of lower values. Graded mucous metaplasia induced in WT and Munc13-2 null tracheas with IL-13, caused proportional increases in BLMS, suggesting that naïve Munc13-2 mouse BLMS is elevated by increased mucin stores. We conclude that BLMS is, [i] a major component of mucin secretion in the lung, [ii] sustained by the mechanical activity of a dynamic lung, [iii] proportional to levels of mucin stores, and [iv] regulated differentially from agonist-induced mucin secretion.
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Fuentes E, Palomo I. Extracellular ATP metabolism on vascular endothelial cells: A pathway with pro-thrombotic and anti-thrombotic molecules. Vascul Pharmacol 2015; 75:1-6. [PMID: 25989108 DOI: 10.1016/j.vph.2015.05.002] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2015] [Revised: 04/16/2015] [Accepted: 05/09/2015] [Indexed: 12/20/2022]
Abstract
Vascular endothelial contributes to the metabolism and interconversion of extracellular adenine nucleotides via ecto-ATPase/ADPase (CD39) and ecto-5'nucleotidase (CD73) activities. These enzymes collectively dephosphorylate ATP, ADP, and AMP with the production of additional adenosine. In the vascular system, adenine nucleotides (ATP and ADP) and nucleoside adenosine represent an important class of extracellular molecules involved in modulating the processes linked to vascular thrombosis exerting various effects in platelets. Yet, the mechanisms by which the extracellular ATP metabolism in the local environment trigger pro-thrombotic and anti-thrombotic states are yet to be fully elucidated. In this article, the relative contribution of extracellular ATP metabolism in platelet regulation is explored.
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Affiliation(s)
- Eduardo Fuentes
- Department of Clinical Biochemistry and Immunohaematology, Faculty of Health Sciences, Interdisciplinary Excellence Research Program on Healthy Aging (PIEI-ES), Universidad de Talca, Talca, Chile; Centro de Estudios en Alimentos Procesados (CEAP), CONICYT-Regional, Gore Maule, R09I2001 Talca, Chile.
| | - Iván Palomo
- Department of Clinical Biochemistry and Immunohaematology, Faculty of Health Sciences, Interdisciplinary Excellence Research Program on Healthy Aging (PIEI-ES), Universidad de Talca, Talca, Chile; Centro de Estudios en Alimentos Procesados (CEAP), CONICYT-Regional, Gore Maule, R09I2001 Talca, Chile.
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Takahara N, Ito S, Furuya K, Naruse K, Aso H, Kondo M, Sokabe M, Hasegawa Y. Real-time imaging of ATP release induced by mechanical stretch in human airway smooth muscle cells. Am J Respir Cell Mol Biol 2015; 51:772-82. [PMID: 24885163 DOI: 10.1165/rcmb.2014-0008oc] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Airway smooth muscle (ASM) cells within the airway walls are continually exposed to mechanical stimuli, and exhibit various functions in response to these mechanical stresses. ATP acts as an extracellular mediator in the airway. Moreover, extracellular ATP is considered to play an important role in the pathophysiology of asthma and chronic obstructive pulmonary disease. However, it is not known whether ASM cells are cellular sources of ATP secretion in the airway. We therefore investigated whether mechanical stretch induces ATP release from ASM cells. Mechanical stretch was applied to primary human ASM cells cultured on a silicone chamber coated with type I collagen using a stretching apparatus. Concentrations of ATP in cell culture supernatants measured by luciferin-luciferase bioluminescence were significantly elevated by cyclic stretch (12 and 20% strain). We further visualized the stretch-induced ATP release from the cells in real time using a luminescence imaging system, while acquiring differential interference contrast cell images with infrared optics. Immediately after a single uniaxial stretch for 1 second, strong ATP signals were produced by a certain population of cells and spread to surrounding spaces. The cyclic stretch-induced ATP release was significantly reduced by inhibitors of Ca(2+)-dependent vesicular exocytosis, 1,2-bis(o-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid tetraacetoxymethyl ester, monensin, N-ethylmaleimide, and bafilomycin. In contrast, the stretch-induced ATP release was not inhibited by a hemichannel blocker, carbenoxolone, or blockade of transient receptor potential vanilloid 4 by short interfering RNA transfection or ruthenium red. These findings reveal a novel property of ASM cells: mechanically induced ATP release may be a cellular source of ATP in the airway.
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Adam D, Roux-Delrieu J, Luczka E, Bonnomet A, Lesage J, Mérol JC, Polette M, Abély M, Coraux C. Cystic fibrosis airway epithelium remodelling: involvement of inflammation. J Pathol 2014; 235:408-19. [DOI: 10.1002/path.4471] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Revised: 10/02/2014] [Accepted: 10/21/2014] [Indexed: 12/16/2022]
Affiliation(s)
- Damien Adam
- INSERM UMR-S 903, SFR CAP-SANTE (FED 4231); University of Reims Champagne-Ardenne; Reims France
| | - Jacqueline Roux-Delrieu
- INSERM UMR-S 903, SFR CAP-SANTE (FED 4231); University of Reims Champagne-Ardenne; Reims France
| | - Emilie Luczka
- INSERM UMR-S 903, SFR CAP-SANTE (FED 4231); University of Reims Champagne-Ardenne; Reims France
| | - Arnaud Bonnomet
- INSERM UMR-S 903, SFR CAP-SANTE (FED 4231); University of Reims Champagne-Ardenne; Reims France
| | - Julien Lesage
- INSERM UMR-S 903, SFR CAP-SANTE (FED 4231); University of Reims Champagne-Ardenne; Reims France
| | | | - Myriam Polette
- INSERM UMR-S 903, SFR CAP-SANTE (FED 4231); University of Reims Champagne-Ardenne; Reims France
- Laboratory of Histology; University Hospital Centre; Reims France
| | - Michel Abély
- INSERM UMR-S 903, SFR CAP-SANTE (FED 4231); University of Reims Champagne-Ardenne; Reims France
- Pediatric Unit A, American Memorial Hospital; University Hospital Centre; Reims France
| | - Christelle Coraux
- INSERM UMR-S 903, SFR CAP-SANTE (FED 4231); University of Reims Champagne-Ardenne; Reims France
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Lu D, Insel PA. Cellular mechanisms of tissue fibrosis. 6. Purinergic signaling and response in fibroblasts and tissue fibrosis. Am J Physiol Cell Physiol 2013; 306:C779-88. [PMID: 24352335 DOI: 10.1152/ajpcell.00381.2013] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Tissue fibrosis occurs as a result of the dysregulation of extracellular matrix (ECM) synthesis. Tissue fibroblasts, resident cells responsible for the synthesis and turnover of ECM, are regulated via numerous hormonal and mechanical signals. The release of intracellular nucleotides and their resultant autocrine/paracrine signaling have been shown to play key roles in the homeostatic maintenance of tissue remodeling and in fibrotic response post-injury. Extracellular nucleotides signal through P2 nucleotide and P1 adenosine receptors to activate signaling networks that regulate the proliferation and activity of fibroblasts, which, in turn, influence tissue structure and pathologic remodeling. An important component in the signaling and functional responses of fibroblasts to extracellular ATP and adenosine is the expression and activity of ectonucleotideases that attenuate nucleotide-mediated signaling, and thereby integrate P2 receptor- and subsequent adenosine receptor-initiated responses. Results of studies of the mechanisms of cellular nucleotide release and the effects of this autocrine/paracrine signaling axis on fibroblast-to-myofibroblast conversion and the fibrotic phenotype have advanced understanding of tissue remodeling and fibrosis. This review summarizes recent findings related to purinergic signaling in the regulation of fibroblasts and the development of tissue fibrosis in the heart, lungs, liver, and kidney.
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Affiliation(s)
- David Lu
- Department of Pharmacology, University of California, San Diego, La Jolla, California; and
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