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Lin J, Taggart M, Borthwick L, Fisher A, Brodlie M, Sassano MF, Tarran R, Gray MA. Acute cigarette smoke or extract exposure rapidly activates TRPA1-mediated calcium influx in primary human airway smooth muscle cells. Sci Rep 2021; 11:9643. [PMID: 33953304 PMCID: PMC8100124 DOI: 10.1038/s41598-021-89051-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Accepted: 04/19/2021] [Indexed: 11/09/2022] Open
Abstract
Tobacco smoking is the largest risk factor for developing chronic obstructive pulmonary disease (COPD), and is associated with hyperresponsiveness of airway smooth muscle (ASM). Chronic exposure to cigarette smoke (CS) leads to airway inflammation and remodelling. However, the direct effect of gaseous CS or CS extract (CSE) on human airway smooth muscle cell (hASMC) function remains poorly understood. This study investigated the acute effect of CS/CSE on calcium homeostasis, a key regulator of ASM physiology and pathophysiology. Primary hASMC were isolated from non-smoking donor lungs, and subjected to Ca2+ imaging studies. We found that both CS, and CSE, rapidly elevated cytosolic Ca2+ in hASMC through stimulation of plasmalemmal Ca2+ influx, but excluded store-operated and L-type Ca2+ channels as mediators of this effect. Using a specific pharmacological inhibitor, or shRNA-driven knockdown, we established that both CS and CSE stimulated Ca2+ influx in hASMC through the neurogenic pain receptor channel, transient receptor potential ankyrin 1 (TRPA1). CS/CSE-dependent, TRPA1-mediated Ca2+ influx led to myosin light-chain phosphorylation, a key process regulating ASM contractility. We conclude that TRPA1 is likely an important link between CS/CSE exposure and airway hyperresponsiveness, and speculate that acute CS/CSE-induced Ca2+ influx could lead to exacerbated ASM contraction and potentially initiate further chronic pathological effects of tobacco smoke.
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Affiliation(s)
- JinHeng Lin
- Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, NE2 4HH, Tyne and Wear, UK
| | - Michael Taggart
- Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, NE2 4HH, Tyne and Wear, UK
| | - Lee Borthwick
- Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, NE2 4HH, Tyne and Wear, UK
| | - Andrew Fisher
- Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, Tyne and Wear, UK
| | - Malcolm Brodlie
- Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, Tyne and Wear, UK
- Paediatric Respiratory Medicine, Great North Children's Hospital, Newcastle Upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, Tyne and Wear, UK
| | - M Flori Sassano
- Department of Cell Biology and Physiology, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Robert Tarran
- Department of Cell Biology and Physiology, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Michael A Gray
- Biosciences Institute, Faculty of Medical Sciences, Newcastle University, Newcastle upon Tyne, NE2 4HH, Tyne and Wear, UK.
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2
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Conklin DJ. Acute cardiopulmonary toxicity of inhaled aldehydes: role of TRPA1. Ann N Y Acad Sci 2016; 1374:59-67. [PMID: 27152448 DOI: 10.1111/nyas.13055] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2015] [Revised: 02/26/2016] [Accepted: 03/07/2016] [Indexed: 12/13/2022]
Abstract
Inhalation of high-level volatile aldehydes, as present in smoke from wildfires and in tobacco smoke, is associated with both acute and chronic cardiopulmonary morbidity and mortality, but the underlying mechanisms are unclear. The transient receptor potential ankyrin 1 (TRPA1) protein forms a cation channel (irritant receptor) that mediates tobacco smoke-induced airway and lung injury, yet the role of TRPA1 in the cardiovascular toxicity of aldehyde exposure is unclear. Physiologically, airway-located TRPA1 activation triggers an irritant response (e.g., coughing and "respiratory braking") that alters the rate and depth of breathing to reduce exposure. Acrolein (2-propenal), a volatile, unsaturated aldehyde, activates TRPA1. Acrolein was used as a chemical weapon in World War I and is present at high levels in wildfires and tobacco smoke. Acrolein is thought to contribute to pulmonary and cardiovascular injury caused by tobacco smoke exposure, although the role of TRPA1 in cardiovascular toxicity is unclear. This minireview addresses this gap in our knowledge by exploring literature and recent data indicating a connection between TRPA1 and cardiovascular as well as pulmonary injury due to inhaled aldehydes.
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Affiliation(s)
- Daniel J Conklin
- Diabetes and Obesity Center, Institute of Molecular Cardiology, Division of Cardiovascular Medicine, Department of Medicine, University of Louisville, Louisville, Kentucky
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3
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Black JL, Panettieri RA, Banerjee A, Berger P. Airway smooth muscle in asthma: just a target for bronchodilation? Clin Chest Med 2012; 33:543-58. [PMID: 22929101 DOI: 10.1016/j.ccm.2012.05.002] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Airway smooth muscle (ASM) has long been recognized as the main cell type responsible for bronchial hyperresponsiveness. It has, thus, been considered as a target for bronchodilation. In asthma, however, there is a complex relationship between ASM and inflammatory cells, such as mast cells and T lymphocytes. Moreover, the increased ASM mass in asthmatic airways is one of the key features of airway remodeling. This article aims to review the main concepts about the 3 possible roles of ASM in asthma: (1) contractile tone, (2) inflammatory response, and (3) remodeling.
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Affiliation(s)
- Judith L Black
- University of Sydney, Discipline of Pharmacology and Woolcock Institute of Medical Research, University of Sydney, Sydney, New South Wales, 2006, Australia
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4
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Mbikou P, Fajmut A, Brumen M, Roux E. Contribution of Rho kinase to the early phase of the calcium-contraction coupling in airway smooth muscle. Exp Physiol 2010; 96:240-58. [PMID: 20870731 DOI: 10.1113/expphysiol.2010.054635] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
We investigated theoretically and experimentally the role of Rho kinase (RhoK) in Ca(2+)-contraction coupling in rat airways. Isometric contraction was measured on tracheal, extrapulmonary and intrapulmonary bronchial rings. Intracellular [Ca(2+)] was recorded in freshly isolated tracheal myocytes. Stimulation by carbachol (0.3 and 10 μm) and 50 mm external KCl induced a short-time, Hill-shaped contraction obtained within 90 s, followed by a sustained or an additional delayed contraction. Responses of [Ca(2+)](i) to acetylcholine consisted in a fast peak followed by a plateau and, in 42% of the cells, superimposed Ca(2+) oscillations. The RhoK inhibitor Y27632 (10 μm) did not alter the [Ca(2+)](i) response. Whatever the agonist, Y27632 did not modify the basal tension but decreased the amplitude of the short-duration response, without altering the additional delayed contraction. The Myosin Light Chain Phosphatase (MLCP) inhibitor calyculin A increased the basal tension and abolished the effect of RhoK. KN93 (Ca(2+)-calmodulin-dependent protein kinase II inhibitor) and DIDS (inhibitor of Ca(2+)-activated Cl(-) channels) had no influence on the RhoK effect. We built a theoretical model of Ca(2+)-dependent active/inactive RhoK ratio and subsequent RhoK-dependent MLCP inactivation, which was further coupled with a four-state model of the contractile apparatus and Ca(2+)-dependent MLCK activation. The model explains the time course of the short-duration contraction and the role of RhoK by Ca(2+)-dependent activation of MLCK and RhoK, which inactivates MLCP. Oscillatory and non-oscillatory [Ca(2+)](i) responses result in a non-oscillatory contraction, the amplitude of which is encoded by the plateau value and oscillation frequency. In conclusion, Ca(2+)-dependent but CaMK II-independent RhoK activation contributes to the early phase of the contractile response via MLCP inhibition.
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Affiliation(s)
- Prisca Mbikou
- Laboratoire de Physiologie Cellulaire Respiratoire, INSERM U885, Université Victor Segalen Bordeaux 2, 146 rue Léo-Saignat, Bordeaux cedex, France
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5
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Marhl M, Gosak M, Perc M, Roux E. Importance of cell variability for calcium signaling in rat airway myocytes. Biophys Chem 2010; 148:42-50. [PMID: 20189292 DOI: 10.1016/j.bpc.2010.02.006] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2009] [Revised: 01/26/2010] [Accepted: 02/08/2010] [Indexed: 11/29/2022]
Abstract
Calcium signaling controls several essential physiological functions in different cell types. Hence, it is not surprising that different aspects of Ca(2+) dynamics are in the focus of in-depth and extensive investigations. Efforts concentrate on the development of proper theoretical models that would provide a unified description of Ca(2+) signaling. Remarkably, experimentally recorded Ca(2+) signals exhibit a rather large diversity, which can be observed irrespective of the cell type, measuring techniques, or the nature of the signal. Our goal in the present study therefore is to present a theoretical explanation for the variability observed in experiments, whereby we focus on caffeine-induced Ca(2+) responses in isolated airway myocytes. By employing a stochastic model, we first test whether the observed variability can be attributed to intrinsic fluctuations that are a common feature of biochemical reactions that govern Ca(2+) signalization. We find that stochastic effects, within ranges that correspond to actual conditions in the cell, are far too modest to explain the large diversity observed in experimental data. Foremost, we reveal that only cell variability in theoretical modeling can appropriately describe the observed diversity in single-cell responses.
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Affiliation(s)
- Marko Marhl
- Department of Physics, University of Maribor, Koroska cesta 160, SI-2000 Maribor, Slovenia.
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6
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Giglio D, Andersson M, Aronsson P, Delbro DS, Haraldsson B, Tobin G. Changes in muscarinic receptors in the toad urothelial cell line TBM-54 following acrolein treatment. Clin Exp Pharmacol Physiol 2007; 35:217-22. [PMID: 17941892 DOI: 10.1111/j.1440-1681.2007.04813.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
1. In cyclophosphamide-induced cystitis in the rat, cholinergic function of the bladder and muscarinic receptor expression are altered. In the present study, we investigated whether the toad urothelial cell line TBM-54 expresses functional muscarinic receptors and whether changes in muscarinic receptors can be induced in vitro by treating cells with acrolein, a metabolite of cyclophosphamide causing cystitis. 2. The occurrence of muscarinic receptors on cells was assessed by microphysiometry, a method analysing receptor function by measuring changes in the extracellular acidity rate (ECAR) in response to receptor stimulation. 3. Challenging untreated cells with the muscarinic receptor agonist carbachol gave rise to a concentration-dependent increase in changes in ECAR, with a maximal response at 1 mmol/L carbachol of 51 +/- 6%. Pre-incubating cells with different muscarinic receptor antagonists (i.e. pirenzepine (M(1) receptor selective), methoctramine (M(2)/M(4) receptor selective) and 4-diphenylacetoxy-N-methylpiperidine methobromide (4-DAMP; M(3)/M(1)/M(5) receptor selective)), gave rise to a concentration-dependent decrease in the effects of carbachol (0.5 mmol/L) on changes in ECAR. 4. Western blot analysis was used to determine the expression of all muscarinic receptor subtypes (M(1)-M(5)) by the cell line. Following acrolein treatment, cells were markedly less sensitive to carbachol and the expression of muscarinic M(2) receptors was decreased, whereas the expression of muscarinic M(3) receptors was increased. 5. In conclusion, the urothelial cell line TBM-54 expresses functional muscarinic receptors and exposure to acrolein leads to a modulation in the expression of muscarinic receptors. Consequently, acrolein may have direct effects on muscarinic receptor function and expression that contribute to the pathogenesis of cyclophosphamide-induced cystitis.
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Affiliation(s)
- D Giglio
- Department of Pharmacology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy, Göteborg University, Göteborg, Sweden.
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7
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Lazaar AL, Panettieri RA. Airway smooth muscle as a regulator of immune responses and bronchomotor tone. Clin Chest Med 2006; 27:53-69, vi. [PMID: 16543052 DOI: 10.1016/j.ccm.2005.10.003] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The traditional view of airway smooth muscle (ASM) in asthma, as a purely contractile tissue, seems to be inadequate. Compelling evidence now suggests that ASM plays an important role in regulating bronchomotor tone, in perpetuating airway inflammation, and in remodeling of the airways. This article reviews three distinct functions of ASM cells: the process of excitation-contraction coupling, with a particular focus on the role of cytokines in modulating calcium responses; the processes of smooth muscle cell proliferation and migration; and the synthetic and immunomodulatory function of ASM cells. This article also discusses how altered synthetic function contributes to airway remodeling.
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Affiliation(s)
- Aili L Lazaar
- Pulmonary, Allergy, and Critical Care Division, University of Pennsylvania Medical Center, BRB II/III, 421 Curie Boulevard, Philadelphia, PA 19104-6160, USA.
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8
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Roux E, Noble PJ, Noble D, Marhl M. Modelling of calcium handling in airway myocytes. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2005; 90:64-87. [PMID: 15982722 DOI: 10.1016/j.pbiomolbio.2005.05.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Airway myocytes are the primary effectors of airway reactivity which modulates airway resistance and hence ventilation. Stimulation of airway myocytes results in an increase in the cytosolic Ca(2+) concentration ([Ca(2+)](i)) and the subsequent activation of the contractile apparatus. Many contractile agonists, including acetylcholine, induce [Ca(2+)](i) increase via Ca(2+) release from the sarcoplasmic reticulum through InsP(3) receptors. Several models have been developed to explain the characteristics of InsP(3)-induced [Ca(2+)](i) responses, in particular Ca(2+) oscillations. The article reviews the modelling of the major structures implicated in intracellular Ca(2+) handling, i.e., InsP(3) receptors, SERCAs, mitochondria and Ca(2+)-binding cytosolic proteins. We developed theoretical models specifically dedicated to the airway myocyte which include the major mechanisms responsible for intracellular Ca(2+) handling identified in these cells. These biocomputations pointed out the importance of the relative proportion of InsP(3) receptor isoforms and the respective role of the different mechanisms responsible for cytosolic Ca(2+) clearance in the pattern of [Ca(2+)](i) variations. We have developed a theoretical model of membrane conductances that predicts the variations in membrane potential and extracellular Ca(2+) influx. Stimulation of this model by simulated increase in [Ca(2+)](i) predicts membrane depolarisation, but not great enough to trigger a significant opening of voltage-dependant Ca(2+) channels. This may explain why airway contraction induced by cholinergic stimulation does not greatly depend on extracellular calcium. The development of such models of airway myocytes is important for the understanding of the cellular mechanisms of airway reactivity and their possible modulation by pharmacological agents.
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Affiliation(s)
- Etienne Roux
- Laboratoire de Physiologie Cellulaire Respiratoire, INSERM E 356, Université Victor Segalen Bordeaux 2, 146 rue Léo-Saignat, 33076 Bordeaux cedex, France.
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9
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Girodet PO, Berger P, Martinez B, Marthan R, Advenier C, Molimard M. Paradoxal effect of salbutamol in an in vitro model of bronchoprotection. Fundam Clin Pharmacol 2005; 19:179-86. [PMID: 15810898 DOI: 10.1111/j.1472-8206.2005.00320.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Salbutamol-induced hyperresponsiveness to acetylcholine was investigated in human and guinea-pig isolated airways and cultured human airway smooth muscle cells. Salbutamol (10(-7)-10(-5) m) inhibited contractions induced by low concentrations of acetylcholine (10(-8)-10(-7) m) but potentiated contractions induced by higher concentrations of acetylcholine (10(-5)-10(-3) m). Pretreatment with the calcium channel antagonist nicardipine suppressed salbutamol-induced hyperresponse. Stimulation of cultured human airway smooth muscle cells with salbutamol (10(-6) m) amplified intracellular calcium concentration rise induced by acetylcholine (10(-5) m). Propranolol (10(-7) m), a beta1- and beta2-adrenoceptor antagonist, and ICI 118551 (10(-7)-10(-6) m), a beta2-adrenoceptor antagonist, suppressed the inhibitory effect of salbutamol but did not inhibit the hyperresponse on high concentrations of acetylcholine. In contrast, higher concentration of propranolol (10(-6) m) inhibited salbutamol-induced hyperreactivity. Effects of salbutamol were not affected by atenolol, a beta1-adrenoceptor blocker. Salbutamol-induced hyperresponsiveness is mediated through a mechanism involving calcium channel activation.
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Affiliation(s)
- P O Girodet
- Laboratoire de Pharmacologie Respiratoire, Université Victor Segalen Bordeaux 2, 33076 Bordeaux, France
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10
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Roux E, Marhl M. Role of sarcoplasmic reticulum and mitochondria in Ca2+ removal in airway myocytes. Biophys J 2004; 86:2583-95. [PMID: 15041694 PMCID: PMC1304105 DOI: 10.1016/s0006-3495(04)74313-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2003] [Accepted: 12/24/2003] [Indexed: 10/24/2022] Open
Abstract
The aim of this study was to use both a theoretical and experimental approach to determine the influence of the sarco-endoplasmic Ca2+-ATPase (SERCA) activity and mitochondria Ca2+ uptake on Ca2+ homeostasis in airway myocytes. Experimental studies were performed on myocytes freshly isolated from rat trachea. [Ca2+]i was measured by microspectrofluorimetry using indo-1. Stimulation by caffeine for 30 s induced a concentration-graded response characterized by a transient peak followed by a progressive decay to a plateau phase. The decay phase was accelerated for 1-s stimulation, indicating ryanodine receptor closure. In Na2+-Ca2+-free medium containing 0.5 mM La3+, the [Ca2+]i response pattern was not modified, indicating no involvement of transplasmalemmal Ca2+ fluxes. The mathematical model describing the mechanism of Ca2+ handling upon RyR stimulation predicts that after Ca2+ release from the sarcoplasmic reticulum, the Ca2+ is first sequestrated by cytosolic proteins and mitochondria, and pumped back into the sarcoplasmic reticulum after a time delay. Experimentally, we showed that the [Ca2+]i decay after Ca2+ increase was not altered by the SERCA inhibitor cyclopiazonic acid, but was slightly but significantly modified by the mitochondria uncoupler carbonyl cyanide 4-(trifluoromethoxy)phenylhydrazone. The experimental and theoretical results indicate that, although Ca2+ pumping back by SERCA is active, it is not primarily involved in [Ca2+]i decrease that is due, in part, to mitochondrial Ca2+ uptake.
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Affiliation(s)
- Etienne Roux
- Laboratoire de Physiologie Cellulaire Respiratoire, Institut National de la Santé et de Recherche Médicale E 356, Université Victor Segalen Bordeaux 2, 33076 Bordeaux, France.
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11
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Roux E, Duvert M, Marthan R. Combined effect of chronic hypoxia and in vitro exposure to gas pollutants on airway reactivity. Am J Physiol Lung Cell Mol Physiol 2002; 283:L628-35. [PMID: 12169583 DOI: 10.1152/ajplung.00387.2001] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
This study investigated the interaction between exposure to air pollutants and chronic hypoxia (CH). We used a hypobaric chamber (14 days at barometric pressure 380 mmHg) to produce CH in rats. Exposure to various doses of acrolein or ozone did not modify the mechanical response to cholinergic agonists. Exposure to 3 microM/min acrolein did not alter epithelium-free trachea responsiveness. In contrast, direct exposure of freshly isolated myocytes to 2 and 3 microM/min acrolein enhanced the amplitude of the first intracellular [Ca(2+)] rise in response to 0.1 microM ACh and the calcium oscillation frequency in response to 10 microM ACh. CH alone did not alter smooth muscle cross-sectional area (SMA) or epithelium-plus-submucosa thickness. CH decreased maximal contractile response (maximal force normalized to SMA) but increased sensitivity (pEC(50)) to cholinergic agonists. We conclude that unlike in normoxic rats, exposure to air pollutants does not induce airway hyperresponsiveness in CH rats, although it increased calcium signaling. These results cannot be explained by change in smooth muscle accessibility, but may be linked to the effect of CH on calcium-contraction coupling.
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Affiliation(s)
- Etienne Roux
- Laboratoire de Physiologie Cellulaire Respiratoire, Institut National de la Santé et de la Recherche Médicale Equipe Mixte 9937, Université Victor Segalen Bordeaux 2, 33076 Bordeaux cedex, France.
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12
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Janssen LJ. Ionic mechanisms and Ca(2+) regulation in airway smooth muscle contraction: do the data contradict dogma? Am J Physiol Lung Cell Mol Physiol 2002; 282:L1161-78. [PMID: 12003770 DOI: 10.1152/ajplung.00452.2001] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
In general, excitation-contraction coupling in muscle is dependent on membrane depolarization and hyperpolarization to regulate the opening of voltage-dependent Ca(2+) channels and, thereby, influence intracellular Ca(2+) concentration ([Ca(2+)](i)). Thus Ca(2+) channel blockers and K(+) channel openers are important tools in the arsenals against hypertension, stroke, and myocardial infarction, etc. Airway smooth muscle (ASM) also exhibits robust Ca(2+), K(+), and Cl(-) currents, and there are elaborate signaling pathways that regulate them. It is easy, then, to presume that these also play a central role in contraction/relaxation of ASM. However, several lines of evidence speak to the contrary. Also, too many researchers in the ASM field view the sarcoplasmic reticulum as being centrally located and displacing its contents uniformly throughout the cell, and they have focused almost exclusively on the initial single [Ca(2+)] spike evoked by excitatory agonists. Several recent studies have revealed complex spatial and temporal heterogeneity in [Ca(2+)](i), the significance of which is only just beginning to be appreciated. In this review, we will compare what is known about ion channels in ASM with what is believed to be their roles in ASM physiology. Also, we will examine some novel ionic mechanisms in the context of Ca(2+) handling and excitation-contraction coupling in ASM.
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Affiliation(s)
- Luke J Janssen
- Asthma Research Group, Firestone Institute for Respiratory Health, St. Joseph's Hospital, McMaster University, Hamilton, Ontario, Canada L8N 4A6.
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13
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Amrani Y, Panettieri RA. Modulation of calcium homeostasis as a mechanism for altering smooth muscle responsiveness in asthma. Curr Opin Allergy Clin Immunol 2002; 2:39-45. [PMID: 11964749 DOI: 10.1097/00130832-200202000-00007] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Airway hyperresponsiveness remains a defining characteristic of asthma. Traditional views assert that airway smooth muscle is an important structural effector cell in the bronchi that modulates bronchomotor tone induced by contractile agonists. New evidence, however, suggests that abnormalities in airway smooth muscle functions, induced by variety of extracellular stimuli, may play an important role in the development of airway hyperresponsiveness. Studies using isolated bronchial preparations or cultured cells show that inflammatory mediators and cytokines may alter calcium homeostasis in airway smooth muscle and render the cells nonspecifically hyperreactive to agonists.
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Affiliation(s)
- Yassine Amrani
- Pulmonary and Critical Care Division, Department of Medicine, University of Pennsylvania Medical Center, 848 BRB II/III, 421 Curie Boulevard, Philadelphia, PA 19104, USA.
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14
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Parameswaran K, Janssen LJ, O'Byrne PM. Airway hyperresponsiveness and calcium handling by smooth muscle: a "deeper look". Chest 2002; 121:621-4. [PMID: 11834679 DOI: 10.1378/chest.121.2.621] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
We propose that abnormal calcium handling by the airway smooth muscle may be an important determinant of airway hyperresponsiveness. The amplitude, frequency, or localization of Ca(2+) oscillations in the smooth muscle may determine the degree of airway sensitivity and reactivity, which are characteristic features of asthma.
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Affiliation(s)
- Krishnan Parameswaran
- Asthma Research Group, Department of Medicine, St. Joseph's Healthcare & McMaster University, Hamilton, ON, Canada
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15
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Conklin DJ, Boyce CL, Trent MB, Boor PJ. Amine metabolism: a novel path to coronary artery vasospasm. Toxicol Appl Pharmacol 2001; 175:149-59. [PMID: 11543647 DOI: 10.1006/taap.2001.9238] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We hypothesized that allylamine (AA) induces subendocardial necrosis in mammals via coronary artery (CA) vasospasm. Additionally, AA toxicity is likely dependent on the enzyme semicarbazide-sensitive amine oxidase (SSAO), which is highly expressed in the aorta of rats and humans. We tested whether AA or acrolein (1, 10, 100, and 1000 microM), a highly reactive product of AA metabolism by SSAO, could contract CA or thoracic aorta (TA) in vitro and if the AA effects involved SSAO. AA or acrolein produced a similar pattern of responses in both CA and TA rings at 100 and 1000 microM, including (1) increased basal tension, (2) enhanced agonist-induced contraction (hypercontractility or vasospasm), (3) remarkable, agonist-induced slow wave vasomotion (vasospasm), and (4) irreversible reduction in vessel contractility after 1 mM exposure. Endothelium-dependent acetylcholine-induced relaxation was not altered during vasospasm in either vessel. Pretreatment with the SSAO inhibitor semicarbazide (1 mM; 10 min) prevented or significantly reduced the majority of AA's effects in both CA and TA rings and inhibited 100% of the SSAO activity present in rat TA and human CA and TA. We propose a two-step model for AA induction of CA vasospasm and resultant myocardial necrosis: (1) metabolism of AA to acrolein by coronary arterial SSAO activity and (2) acrolein induction of CA vasospasm independent of endothelial injury-a novel path.
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Affiliation(s)
- D J Conklin
- Biology Department, University of Wisconsin-Eau Claire, Eau Claire, Wisconsin 54702-4004, USA
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16
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Berger P, Tunon-De-Lara JM, Savineau JP, Marthan R. Selected contribution: tryptase-induced PAR-2-mediated Ca(2+) signaling in human airway smooth muscle cells. J Appl Physiol (1985) 2001; 91:995-1003. [PMID: 11457819 DOI: 10.1152/jappl.2001.91.2.995] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Tryptase, the major mast cell product, is considered to play an important role in airway inflammation and hyperresponsiveness. Tryptase produces different, sometimes opposite, effects on airway responsiveness (bronchoprotection and/or airway contraction). This study was designed to examine the effect of human lung tryptase and activation of protease-activated receptor (PAR)-2 by synthetic activated peptide (AP) SLIGKV-NH(2) on Ca(2+) signaling in human airway smooth muscle (HASM) cells. Immunocytochemistry revealed that PAR-2 was expressed by HASM cells. Tryptase (7.5--30 mU/ml) induced a concentration-dependent transient relative rise in cytoplasmic Ca(2+) concentration ([Ca(2+)](i)) that reached 207 +/- 32 nM (n = 10) measured by indo 1 spectrofluorometry. The protease inhibitors leupeptin or benzamidine (100 microM) abolished tryptase-induced [Ca(2+)](i) increase. Activation of PAR-2 by AP (1-100 microM) also induced a concentration-dependent transient rise in [Ca(2+)](i), whereas the reverse peptide produced no effect. There was a homologous desensitization of the [Ca(2+)](i) response on repeated stimulation with tryptase or AP. U-73122, a specific phospholipase C (PLC) antagonist, xestospongin, an inositol trisphosphate (IP(3))-receptor antagonist, or thapsigargin, a sarcoplamic Ca(2+)-ATPase inhibitor, abolished tryptase-induced [Ca(2+)](i) response, whereas Ca(2+) removal, in the additional presence of EGTA, had no effect. Calphostin C, a protein kinase C inhibitor, increased PAR-2 [Ca(2+)](i) response. Our results indicate that tryptase activates a [Ca(2+)](i) response, which appears as PAR-2 mediated in HASM cells. Signal transduction implicates the intracellular Ca(2+) store via PLC activation and thus via the IP(3) pathway. This study provides evidence that tryptase, which is increasingly recognized as an important mediator in airway inflammation and hyperresponsiveness, is also a potent direct agonist at the site of airway smooth muscle.
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Affiliation(s)
- P Berger
- Laboratoire de Physiologie Cellulaire Respiratoire, Inserm E9937, Université Bordeaux 2, 33076 Bordeaux, France
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Hyvelin JM, Savineau JP, Marthan R. Selected contribution: effect of the aldehyde acrolein on acetylcholine-induced membrane current in airway smooth muscle cells. J Appl Physiol (1985) 2001; 90:750-4. [PMID: 11160078 DOI: 10.1152/jappl.2001.90.2.750] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Acrolein administered to isolated airways has been shown to alter airway responsiveness as a consequence of its effect on Ca(2+) signaling. To examine the mechanisms involved, we studied the effect of acrolein on ACh- and caffeine-induced membrane currents (patch-clamp) in myocytes freshly isolated from rat trachea. In cells clamped at -60 mV, ACh (0.1-10 microM) induced a concentration-dependent inward current, which, in approximately 50% of the cells, was followed by current oscillations in response to high concentration of ACh (10 microM). Exposure to acrolein (0.2 microM) for 10 min significantly enhanced the amplitude of the low-ACh (0.1 microM) concentration-induced initial peak of current (318.8 +/- 28.3 vs. 251.2 +/- 40.3 pA; n = 25, P < 0.05). At a high-ACh concentration (10 microM), the frequency at which subsequent peaks occurred was significantly increased (13.2 +/- 1.1 vs. 8.7 +/- 2 min(-1); n = 20, P < 0.05). ACh-induced current was identified as a Ca(2+)-activated Cl(-) current. In contrast, similar exposure to acrolein, which does not alter caffeine-induced Ca(2+) release, did not alter caffeine-induced transient membrane currents (595 +/- 45 and 640 +/- 45 pA in control cells and in cells exposed to acrolein, respectively; n = 15). It is concluded that acrolein alters ACh-induced current as a consequence of its effect on the cytosolic Ca(2+) concentration response and that the protective role of inhibitors of Cl(-) channels in air pollutant-induced airway hyperresponsiveness should be examined.
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Affiliation(s)
- J M Hyvelin
- Laboratoire de Physiologie Cellulaire Respiratoire, Institut National de la Santé et de la Recherche Médicale E9937, Université Bordeaux 2, 33076 Bordeaux, France
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Hyvelin JM, Roux E, Prévost MC, Savineau JP, Marthan R. Cellular mechanisms of acrolein-induced alteration in calcium signaling in airway smooth muscle. Toxicol Appl Pharmacol 2000; 164:176-83. [PMID: 10764631 DOI: 10.1006/taap.1999.8879] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Acrolein, an unsaturated aliphatic aldehyde, is a potent respiratory irritant. We have previously observed that acrolein administered ex vivo to isolated airways alters subsequent airway responsiveness to muscarinic agonists in terms of both mechanical activity of rings and calcium signaling in isolated cells. In the present study, we have examined the mechanisms by which acrolein alters Ca(2+) signaling. In freshly isolated rat tracheal smooth muscle cells, preexposure to acrolein increased the [Ca(2+)](i) oscillation frequency in response to endothelin 1 (ET-1, 0.1 microM), a contractile agonist that acts via the activation of a receptor different from the muscarinic cholinoceptor. We then studied acrolein-induced alteration in cell signaling with special attention to the steps downstream of membrane receptor activation i.e., the inositol 1,4,5-trisphosphate (InsP(3)) signaling pathway. Pretreatment of cells with LiCl (20 mM), a modulator of InsP(3) concentration, mimicked the effect of acrolein exposure on agonist-induced [Ca(2+)](i) response, i.e., increased the amplitude of the first Ca(2+) rise and the oscillation frequency in response to 0.1 and 10 microM acetylcholine (ACh), respectively. Moreover, in tracheal smooth muscle, preexposure to acrolein significantly increased carbachol-induced [(3)H]inositol-phosphates accumulation, up to 34 +/- 11% above unexposed tissue values. Finally, in beta-escin permeabilized cells, injection of InsP(3) (0.1-10 microM) induced a concentration-dependent [Ca(2+)](i) rise followed, for high InsP(3) concentration, by [Ca(2+)](i) oscillations, a calcium response whose pattern was similar to that induced by ACh. Exposure to acrolein did not alter the InsP(3)-induced [Ca(2+)](i) response. These results indicate that the effect of acrolein exposure on Ca(2+) responses in airway smooth muscle is not restricted to activation of the muscarinic cholinoceptor and is due to an enhancement in agonist-induced InsP(3) production. Since acrolein does not modify InsP(3) receptor channel sensitivity, we conclude that acrolein-induced alteration in calcium signaling can be ascribed to its sole effect on InsP(3) production.
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Affiliation(s)
- J M Hyvelin
- Laboratoire de Physiologie Cellulaire Respiratoire INSERM E9937, Université Bordeaux 2, Bordeaux, 33076, France
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Savineau JP, Marthan R. Cytosolic Calcium Oscillations in Smooth Muscle Cells. NEWS IN PHYSIOLOGICAL SCIENCES : AN INTERNATIONAL JOURNAL OF PHYSIOLOGY PRODUCED JOINTLY BY THE INTERNATIONAL UNION OF PHYSIOLOGICAL SCIENCES AND THE AMERICAN PHYSIOLOGICAL SOCIETY 2000; 15:50-55. [PMID: 11390877 DOI: 10.1152/physiologyonline.2000.15.1.50] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In a variety of smooth muscle cells, agonists activating membrane receptors induce oscillations in the cytoplasmic Ca(2+) concentration via an inositol trisphosphate-activated mechanism. Ca(2+) oscillations participate in the control of cell membrane potential and the tone of smooth muscle. There is evidence that alterations in Ca(2+) oscillations modulate smooth muscle responsiveness.
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Affiliation(s)
- Jean-Pierre Savineau
- Laboratoire de Physiologie Cellulaire Respiratoire, INSERM (E n degrees 9937), Université Victor Ségalen Bordeaux 2, 146 rue Léo Saignat, 33076 Bordeaux Cédex, France
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Roux E, Hyvelin JM, Savineau JP, Marthan R. Human isolated airway contraction: interaction between air pollutants and passive sensitization. Am J Respir Crit Care Med 1999; 160:439-45. [PMID: 10430711 DOI: 10.1164/ajrccm.160.2.9811007] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Although there is epidemiological evidence that an increase in allergic diseases such as asthma may be linked to air pollution, there is little experimental data to address this issue. The aim of this study was thus to investigate the interaction between passive sensitization and exposure to pollutants in human isolated airways. We have examined (1) the effect of a preexposure to pollutants on the contraction of sensitized bronchi to a specific antigen, and (2) the effect of passive sensitization on the contraction to nonspecific agonists in bronchi preexposed to pollutants. In tissues sensitized by incubation in sera from asthmatic patients, preexposure to 0.3 microM acrolein (an aldehyde) for 10 min or 20 min significantly increased the maximal contractile response to the antigen Dermatophagoides pteronyssinus (D. pter.) by 20.5 +/- 6.5 and 34.9 +/- 7.4%, respectively. Similarly, preexposure to ozone (1 ppm for 20 min) increased the response to D. pter. by 25.3 +/- 11.3%. On the other hand, passive sensitization increased the contractile response to carbachol or histamine of bronchial rings preexposed to 0.3 microM acrolein for 10 min by 33.5 +/- 6.2% and 32.5 +/- 5.1%, respectively. This study provides a proof of principle in vitro for a combined effect of immunological sensitization and exposure to pollutants, i.e., passive sensitization and exposure to pollutants act in a synergistic manner on human bronchial smooth muscle reactivity in response to both specific antigen and nonspecific agonists.
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Affiliation(s)
- E Roux
- Laboratoire de Physiologie Cellulaire Respiratoire, INSERM E9937, Université Bordeaux 2, Bordeaux, France
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