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The role of PGE2 and EP receptors on lung's immune and structural cells; possibilities for future asthma therapy. Pharmacol Ther 2023; 241:108313. [PMID: 36427569 DOI: 10.1016/j.pharmthera.2022.108313] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2022] [Revised: 10/06/2022] [Accepted: 11/17/2022] [Indexed: 11/27/2022]
Abstract
Asthma is the most common airway chronic disease with treatments aimed mainly to control the symptoms. Adrenergic receptor agonists, corticosteroids and anti-leukotrienes have been used for decades, and the development of more targeted asthma treatments, known as biological therapies, were only recently established. However, due to the complexity of asthma and the limited efficacy as well as the side effects of available treatments, there is an urgent need for a new generation of asthma therapies. The anti-inflammatory and bronchodilatory effects of prostaglandin E2 in asthma are promising, yet complicated by undesirable side effects, such as cough and airway irritation. In this review, we summarize the most important literature on the role of all four E prostanoid (EP) receptors on the lung's immune and structural cells to further dissect the relevance of EP2/EP4 receptors as potential targets for future asthma therapy.
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2
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Bonvini SJ, Birrell MA, Dubuis E, Adcock JJ, Wortley MA, Flajolet P, Bradding P, Belvisi MG. Novel airway smooth muscle-mast cell interactions and a role for the TRPV4-ATP axis in non-atopic asthma. Eur Respir J 2020; 56:13993003.01458-2019. [PMID: 32299856 PMCID: PMC7330131 DOI: 10.1183/13993003.01458-2019] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Accepted: 02/27/2020] [Indexed: 01/28/2023]
Abstract
Mast cell–airway smooth muscle (ASM) interactions play a major role in the immunoglobulin (Ig)E- dependent bronchoconstriction seen in asthma but less is known about IgE-independent mechanisms of mast cell activation. Transient receptor potential cation channel, subfamily V, member 4 (TRPV4) activation causes contraction of human ASM via the release of cysteinyl leukotrienes (cysLTs) but the mechanism is unknown. The objective of the present study was to investigate a role for IgE-independent, mast cell–ASM interaction in TRPV4-induced bronchospasm. A technique not previously applied to respiratory research now uncovers important IgE-independent mechanisms involved in human mast cell–airway smooth muscle interactions that may be responsible for the bronchospasm associated with non-atopic asthmahttp://bit.ly/2U1n5nT
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Affiliation(s)
- Sara J Bonvini
- Respiratory Pharmacology Group, Airway Disease, National Heart and Lung Institute, Imperial College London, London, UK.,Research and Early Development, Respiratory and Immunology, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden.,Contributed equally
| | - Mark A Birrell
- Respiratory Pharmacology Group, Airway Disease, National Heart and Lung Institute, Imperial College London, London, UK.,Research and Early Development, Respiratory and Immunology, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden.,Contributed equally
| | - Eric Dubuis
- Respiratory Pharmacology Group, Airway Disease, National Heart and Lung Institute, Imperial College London, London, UK
| | - John J Adcock
- Respiratory Pharmacology Group, Airway Disease, National Heart and Lung Institute, Imperial College London, London, UK.,Research and Early Development, Respiratory and Immunology, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Michael A Wortley
- Respiratory Pharmacology Group, Airway Disease, National Heart and Lung Institute, Imperial College London, London, UK
| | - Pauline Flajolet
- Respiratory Pharmacology Group, Airway Disease, National Heart and Lung Institute, Imperial College London, London, UK
| | - Peter Bradding
- Dept of Infection, Immunity and Inflammation, University of Leicester University, Institute for Lung Health, Glenfield Hospital, Leicester, UK
| | - Maria G Belvisi
- Respiratory Pharmacology Group, Airway Disease, National Heart and Lung Institute, Imperial College London, London, UK .,Research and Early Development, Respiratory and Immunology, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
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3
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Coleman RA, Woodrooffe AJ, Clark KL, Toris CB, Fan S, Wang JW, Woodward DF. The affinity, intrinsic activity and selectivity of a structurally novel EP 2 receptor agonist at human prostanoid receptors. Br J Pharmacol 2019; 176:687-698. [PMID: 30341781 PMCID: PMC6365485 DOI: 10.1111/bph.14525] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2017] [Revised: 09/14/2018] [Accepted: 09/26/2018] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND AND PURPOSE Prostanoid EP2 receptor agonists exhibit several activities including ocular hypotension, tocolysis and anti-inflammatory activity. This report describes the affinity and selectivity of a structurally novel, non-prostanoid EP2 receptor agonist, PGN-9856, and its therapeutic potential. EXPERIMENTAL APPROACH The pharmacology of a series of non-prostanoid EP2 receptor agonists was determined according to functional and radioligand binding studies, mostly using human recombinant prostanoid receptor transfectants. The selectivity of PGN-9856, as the preferred compound, was subsequently determined by using a diverse variety of non-prostanoid target proteins. The therapeutic potential of PGN-9856 was addressed by determining its activity in relevant primate cell, tissue and disease models. KEY RESULTS PGN-9856 was a selective and high affinity (pKi ≥ 8.3) ligand at human recombinant EP2 receptors. In addition to high affinity binding, it was a potent and full EP2 receptor agonist with a high level of selectivity at EP1 , EP3 , EP4 , DP, FP, IP and TP receptors. In cells overexpressing human recombinant EP2 receptors, PGN-9856 displayed a potency (pEC50 ≥ 8.5) and a maximal response (increase in cAMP) comparable to that of the endogenous agonist PGE2 . PGN-9856 exhibited no appreciable affinity (up 10 μM) for a range of 53 other receptors, ion channels and enzymes. Finally, PGN-9856 exhibited tocolytic, anti-inflammatory and long-acting ocular hypotensive properties consistent with its potent EP2 receptor agonist properties. CONCLUSIONS AND IMPLICATIONS PGN-9856 is a potent, selective and efficacious prostanoid EP2 receptor agonist with diverse potential therapeutic applications: tocolytic, anti-inflammatory and notably anti-glaucoma.
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Affiliation(s)
| | | | | | - C B Toris
- University of Nebraska Medical Center, Omaha, NE, USA
| | - S Fan
- University of Nebraska Medical Center, Omaha, NE, USA
| | - J W Wang
- JeniVision Inc., Irvine, CA, USA
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4
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Selectively targeting prostanoid E (EP) receptor-mediated cell signalling pathways: Implications for lung health and disease. Pulm Pharmacol Ther 2018; 49:75-87. [DOI: 10.1016/j.pupt.2018.01.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Revised: 01/05/2018] [Accepted: 01/25/2018] [Indexed: 12/18/2022]
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Gill SK, Yao Y, Kay LJ, Bewley MA, Marriott HM, Peachell PT. The anti-inflammatory effects of PGE 2 on human lung macrophages are mediated by the EP 4 receptor. Br J Pharmacol 2016; 173:3099-3109. [PMID: 27460634 DOI: 10.1111/bph.13565] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Revised: 07/19/2016] [Accepted: 07/19/2016] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND AND PURPOSE PGE2 inhibits cytokine generation from human lung macrophages. However, the EP receptor that mediates this beneficial anti-inflammatory effect of PGE2 has not been defined. The aim of this study was to identify the EP receptor by which PGE2 inhibits cytokine generation from human lung macrophages. This was determined by using recently developed EP receptor ligands. EXPERIMENTAL APPROACH The effects of PGE2 and EP-selective agonists on LPS-induced generation of TNF-α and IL-6 from macrophages were evaluated. The effects of EP2 -selective (PF-04852946, PF-04418948) and EP4 -selective (L-161,982, CJ-042794) receptor antagonists on PGE2 responses were studied. The expression of EP receptor subtypes by human lung macrophages was determined by RT-PCR. KEY RESULTS PGE2 inhibited LPS-induced and Streptococcus pneumoniae-induced cytokine generation from human lung macrophages. Analysis of mRNA levels indicated that macrophages expressed EP2 and EP4 receptors. L-902,688 (EP4 receptor-selective agonist) was considerably more potent than butaprost (EP2 receptor-selective agonist) as an inhibitor of TNF-α generation from macrophages. EP2 receptor-selective antagonists had marginal effects on the PGE2 inhibition of TNF-α generation, whereas EP4 receptor-selective antagonists caused rightward shifts in the PGE2 concentration-response curves. CONCLUSIONS AND IMPLICATIONS These studies demonstrate that the EP4 receptor is the principal receptor that mediates the anti-inflammatory effects of PGE2 on human lung macrophages. This suggests that EP4 receptor agonists could be effective anti-inflammatory agents in human lung disease.
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Affiliation(s)
- Sharonjit K Gill
- Academic Unit of Respiratory Medicine, Department of Infection, Immunity and Cardiovascular Disease, The Medical School (Floor L), University of Sheffield, Sheffield, UK
| | - Yiwen Yao
- Academic Unit of Respiratory Medicine, Department of Infection, Immunity and Cardiovascular Disease, The Medical School (Floor L), University of Sheffield, Sheffield, UK
| | - Linda J Kay
- Academic Unit of Respiratory Medicine, Department of Infection, Immunity and Cardiovascular Disease, The Medical School (Floor L), University of Sheffield, Sheffield, UK
| | - Martin A Bewley
- Academic Unit of Respiratory Medicine, Department of Infection, Immunity and Cardiovascular Disease, The Medical School (Floor L), University of Sheffield, Sheffield, UK
| | - Helen M Marriott
- Academic Unit of Respiratory Medicine, Department of Infection, Immunity and Cardiovascular Disease, The Medical School (Floor L), University of Sheffield, Sheffield, UK
| | - Peter T Peachell
- Academic Unit of Respiratory Medicine, Department of Infection, Immunity and Cardiovascular Disease, The Medical School (Floor L), University of Sheffield, Sheffield, UK.
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6
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Serra-Pages M, Torres R, Plaza J, Herrerias A, Costa-Farré C, Marco A, Jiménez M, Maurer M, Picado C, de Mora F. Activation of the Prostaglandin E2 receptor EP2 prevents house dust mite-induced airway hyperresponsiveness and inflammation by restraining mast cells' activity. Clin Exp Allergy 2016; 45:1590-600. [PMID: 25823713 DOI: 10.1111/cea.12542] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2014] [Revised: 03/02/2015] [Accepted: 03/03/2015] [Indexed: 01/31/2023]
Abstract
BACKGROUND Prostaglandin E2 (PGE2 ) has been proposed to exert antiasthmatic effects in patients, to prevent antigen-induced airway pathology in murine models, and to inhibit mast cells (MC) activity in vitro. OBJECTIVE To assess in a murine model whether the protective effect of PGE2 may be a consequence of its ability to activate the E-prostanoid (EP)2 receptor on airway MC. METHODS Either BALB/c or C57BL/6 mice were exposed intranasally (i.n.) to house dust mite (HDM) aeroallergens. Both strains were given PGE2 locally (0.3 mg/kg), but only BALB/c mice were administered butaprost (EP2 agonist: 0.3 mg/kg), or AH6809 (EP2 antagonist; 2.5 mg/kg) combined with the MC stabilizer sodium cromoglycate (SCG: 25 mg/kg). Airway hyperresponsiveness (AHR) and inflammation, along with lung MC activity, were evaluated. In addition, butaprost's effect was assessed in MC-mediated passive cutaneous anaphylaxis (PCA) in mice challenged with 2,4-dinitrophenol (DNP). RESULTS Selective EP2 agonism attenuated aeroallergen-caused AHR and inflammation in HDM-exposed BALB/c mice, and this correlated with a reduced lung MC activity. Accordingly, the blockade of endogenous PGE2 by means of AH6809 worsened airway responsiveness in sensitive BALB/c mice, and such worsening was reversed by SCG. The relevance of MC to PGE2 -EP2 driven protection was further highlighted in MC-dependent PCA, where butaprost fully prevented MC-induced ear swelling. Unlike in BALB/c mice, PGE2 did not protect the airways of HDM-sensitized C57BL/6 animals, a strain in which we showed MC to be irrelevant to aeroallergen-driven AHR and inflammation. CONCLUSIONS & CLINICAL RELEVANCE The beneficial effect of both exogenous and endogenous PGE2 in aeroallergen-sensitized mice may be attributable to the activation of the EP2 receptor, which in turn acts as a restrainer of airway MC activity. This opens a path towards the identification of therapeutic targets against asthma along the 'EP2 -MC-airway' axis.
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Affiliation(s)
- M Serra-Pages
- Department of Pharmacology, Therapeutics and Toxicology, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - R Torres
- Department of Pharmacology, Therapeutics and Toxicology, Universitat Autònoma de Barcelona, Barcelona, Spain.,CIBER (Centro de Investigación Biomédica en Red) de Enfermedades Respiratorias, Barcelona, Spain.,Department of Cellular Biology, Physiology and Immunology, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - J Plaza
- Department of Pharmacology, Therapeutics and Toxicology, Universitat Autònoma de Barcelona, Barcelona, Spain.,CIBER (Centro de Investigación Biomédica en Red) de Enfermedades Respiratorias, Barcelona, Spain
| | - A Herrerias
- Department of Pharmacology, Therapeutics and Toxicology, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - C Costa-Farré
- Department of Surgery and Animals Medicine, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - A Marco
- Department of Surgery and Animals Medicine, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - M Jiménez
- Department of Cellular Biology, Physiology and Immunology, Universitat Autònoma de Barcelona, Barcelona, Spain.,CIBER (Centro de Investigación Biomédica en Red) de Enfermedades Hepáticas y Digestivas
| | - M Maurer
- Department of Dermatology, Charité -Universitätsmedizin Berlin, Berlin, Germany
| | - C Picado
- CIBER (Centro de Investigación Biomédica en Red) de Enfermedades Respiratorias, Barcelona, Spain.,Department of Pneumology and Respiratory Allergy, Hospital Clínic, IDIBAPS (Institut d'Investigacions Biomèdiques August Pi i Sunyer), Universitat de Barcelona, Barcelona, Spain
| | - F de Mora
- Department of Pharmacology, Therapeutics and Toxicology, Universitat Autònoma de Barcelona, Barcelona, Spain
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7
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The PGE2-EP2-mast cell axis: an antiasthma mechanism. Mol Immunol 2014; 63:61-8. [PMID: 24768319 DOI: 10.1016/j.molimm.2014.03.007] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2013] [Revised: 03/05/2014] [Accepted: 03/06/2014] [Indexed: 01/10/2023]
Abstract
Despite the fact that cyclooxygenase and its products, prostaglandins, have been traditionally associated with the development of inflammation, PGE2 was implicated early on as potentially beneficial in asthma. During the 1970s and 1980s, several studies reported the bronchodilator effect of PGE2 in asthma patients. In parallel, it was being shown to exert an inhibitory effect on mast cells in vitro. In spite of this, data supporting the beneficial role for PGE2 in asthma were scarce and sometimes controversial. Many years later, in vitro and in vivo studies suggested a range of biological activities attributable to PGE2, others than the ability to relax smooth muscle, that potentially explained some of the observed positive effects in asthma. The identification and cloning of the four PGE2 receptors made available new tools with which to fine-tune investigation of the anti-inflammatory, pro-inflammatory, immunoregulatory, and bronchodilation mechanisms of PGE2. Among these, several suggested involvement of mast cells, a cell population known to play a fundamental role in acute and chronic asthma. Indeed, it has been shown that PGE2 prevents human and murine MC activity in vitro through activation of the EP2 receptor, and also that both exogenously administered and endogenous PGE2 inhibit airway MC activity in vivo in mouse models of asthma (likely through an EP2-mediated mechanism as well). In the last few years, we have furthered into the functional connection between PGE2-induced mast cells inhibition and attenuated damage, in asthma and allergy models. The validity of the findings supporting a beneficial effect of PGE2 in different asthma phases, the direct effect of PGE2 on mast cells populations, and the functional implications of the PGE2-MC interaction on airway function are some of the topics addressed in this review, under the assumption that increased understanding of the PGE2-EP2-mast cell axis will likely lead to the discovery of novel antiasthma targets.
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8
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Kay LJ, Gilbert M, Pullen N, Skerratt S, Farrington J, Seward EP, Peachell PT. Characterization of the EP receptor subtype that mediates the inhibitory effects of prostaglandin E2 on IgE-dependent secretion from human lung mast cells. Clin Exp Allergy 2014; 43:741-51. [PMID: 23786281 DOI: 10.1111/cea.12142] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2013] [Revised: 04/16/2013] [Accepted: 04/18/2013] [Indexed: 01/11/2023]
Abstract
BACKGROUND Prostaglandin E2 (PGE2 ) has been shown to inhibit IgE-dependent histamine release from human lung mast cells. This effect of PGE2 is believed to be mediated by EP2 receptors. However, definitive evidence that this is the case has been lacking in the absence of EP2 -selective antagonists. Moreover, recent evidence has suggested that PGE2 activates EP4 receptors to inhibit respiratory cell function. OBJECTIVE The aim of this study was to determine the receptor by which PGE2 inhibits human lung mast cell responses by using recently developed potent and selective EP2 and EP4 receptor antagonists alongside other established EP receptor ligands. METHODS The effects of non-selective (PGE2 , misoprostol), EP2 -selective (ONO-AE1-259, AH13205, butaprost-free acid) and EP4 -selective (L-902,688, TCS251) agonists on IgE-dependent histamine release and cyclic-AMP generation in mast cells were determined. The effects of EP2 -selective (PF-04418948, PF-04852946) and EP4 -selective (CJ-042794, L-161,982) antagonists on PGE2 responses of mast cells were studied. The expression of EP receptor subtypes was determined by RT-PCR. RESULTS Prostaglandin E2 , EP2 agonists and EP4 agonists inhibited IgE-dependent histamine release from mast cells. PGE2 and EP2 agonists, but not EP4 agonists, increased cyclic-AMP levels in mast cells. EP4 -selective antagonists did not affect the PGE2 inhibition of histamine release, whereas EP2 -selective antagonists caused rightward shifts in the PGE2 concentration-response curves. RT-PCR studies indicated that mast cells expressed EP2 and EP4 receptors. CONCLUSIONS AND CLINICAL RELEVANCE Although human lung mast cells may express both EP2 and EP4 receptors, the principal mechanism by which PGE2 inhibits mediator release in mast cells is by activating EP2 receptors.
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Affiliation(s)
- L J Kay
- Academic Unit of Respiratory Medicine, The Medical School, University of Sheffield, Sheffield, UK
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9
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Schmidt M, Dekker FJ, Maarsingh H. Exchange protein directly activated by cAMP (epac): a multidomain cAMP mediator in the regulation of diverse biological functions. Pharmacol Rev 2013; 65:670-709. [PMID: 23447132 DOI: 10.1124/pr.110.003707] [Citation(s) in RCA: 203] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Since the discovery nearly 60 years ago, cAMP is envisioned as one of the most universal and versatile second messengers. The tremendous feature of cAMP to tightly control highly diverse physiologic processes, including calcium homeostasis, metabolism, secretion, muscle contraction, cell fate, and gene transcription, is reflected by the award of five Nobel prizes. The discovery of Epac (exchange protein directly activated by cAMP) has ignited a new surge of cAMP-related research and has depicted novel cAMP properties independent of protein kinase A and cyclic nucleotide-gated channels. The multidomain architecture of Epac determines its activity state and allows cell-type specific protein-protein and protein-lipid interactions that control fine-tuning of pivotal biologic responses through the "old" second messenger cAMP. Compartmentalization of cAMP in space and time, maintained by A-kinase anchoring proteins, phosphodiesterases, and β-arrestins, contributes to the Epac signalosome of small GTPases, phospholipases, mitogen- and lipid-activated kinases, and transcription factors. These novel cAMP sensors seem to implement certain unexpected signaling properties of cAMP and thereby to permit delicate adaptations of biologic responses. Agonists and antagonists selective for Epac are developed and will support further studies on the biologic net outcome of the activation of Epac. This will increase our current knowledge on the pathophysiology of devastating diseases, such as diabetes, cognitive impairment, renal and heart failure, (pulmonary) hypertension, asthma, and chronic obstructive pulmonary disease. Further insights into the cAMP dynamics executed by the Epac signalosome will help to optimize the pharmacological treatment of these diseases.
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Affiliation(s)
- Martina Schmidt
- Department of Molecular Pharmacology, Groningen Research Institute for Pharmacy, University of Groningen, 9713 AV Groningen, The Netherlands.
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10
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Kondrashov A, Meijer HA, Barthet-Barateig A, Parker HN, Khurshid A, Tessier S, Sicard M, Knox AJ, Pang L, de Moor CH. Inhibition of polyadenylation reduces inflammatory gene induction. RNA (NEW YORK, N.Y.) 2012; 18:2236-2250. [PMID: 23118416 PMCID: PMC3504674 DOI: 10.1261/rna.032391.112] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2012] [Accepted: 09/14/2012] [Indexed: 05/31/2023]
Abstract
Cordycepin (3' deoxyadenosine) has long been used in the study of in vitro assembled polyadenylation complexes, because it terminates the poly(A) tail and arrests the cleavage complex. It is derived from caterpillar fungi, which are highly prized in Chinese traditional medicine. Here we show that cordycepin specifically inhibits the induction of inflammatory mRNAs by cytokines in human airway smooth muscle cells without affecting the expression of control mRNAs. Cordycepin treatment results in shorter poly(A) tails, and a reduction in the efficiency of mRNA cleavage and transcription termination is observed, indicating that the effects of cordycepin on 3' processing in cells are similar to those described in in vitro reactions. For the CCL2 and CXCL1 mRNAs, the effects of cordycepin are post-transcriptional, with the mRNA disappearing during or immediately after nuclear export. In contrast, although the recruitment of RNA polymerase II to the IL8 promoter is also unaffected, the levels of nascent transcript are reduced, indicating a defect in transcription elongation. We show that a reporter construct with 3' sequences from a histone gene is unaffected by cordycepin, while CXCL1 sequences confer cordycepin sensitivity to the reporter, demonstrating that polyadenylation is indeed required for the effect of cordycepin on gene expression. In addition, treatment with another polyadenyation inhibitor and knockdown of poly(A) polymerase α also specifically reduced the induction of inflammatory mRNAs. These data demonstrate that there are differences in the 3' processing of inflammatory and housekeeping genes and identify polyadenylation as a novel target for anti-inflammatory drugs.
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Affiliation(s)
- Alexander Kondrashov
- School of Pharmacy, The University of Nottingham, Nottingham, NG7 2RD, United Kingdom
| | - Hedda A. Meijer
- School of Clinical Sciences, The University of Nottingham, Nottingham, NG7 2RD, United Kingdom
| | | | - Hannah N. Parker
- School of Pharmacy, The University of Nottingham, Nottingham, NG7 2RD, United Kingdom
| | - Asma Khurshid
- School of Pharmacy, The University of Nottingham, Nottingham, NG7 2RD, United Kingdom
| | - Sarah Tessier
- School of Pharmacy, The University of Nottingham, Nottingham, NG7 2RD, United Kingdom
| | - Marie Sicard
- School of Pharmacy, The University of Nottingham, Nottingham, NG7 2RD, United Kingdom
| | - Alan J. Knox
- School of Clinical Sciences, The University of Nottingham, Nottingham, NG7 2RD, United Kingdom
| | - Linhua Pang
- School of Clinical Sciences, The University of Nottingham, Nottingham, NG7 2RD, United Kingdom
| | - Cornelia H. de Moor
- School of Pharmacy, The University of Nottingham, Nottingham, NG7 2RD, United Kingdom
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11
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Dekkers BGJ, Racké K, Schmidt M. Distinct PKA and Epac compartmentalization in airway function and plasticity. Pharmacol Ther 2012; 137:248-65. [PMID: 23089371 DOI: 10.1016/j.pharmthera.2012.10.006] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2012] [Accepted: 10/09/2012] [Indexed: 12/15/2022]
Abstract
Asthma and chronic obstructive pulmonary disease (COPD) are obstructive lung diseases characterized by airway obstruction, airway inflammation and airway remodelling. Next to inflammatory cells and airway epithelial cells, airway mesenchymal cells, including airway smooth muscle cells and (myo)fibroblasts, substantially contribute to disease features by the release of inflammatory mediators, smooth muscle contraction, extracellular matrix deposition and structural changes in the airways. Current pharmacological treatment of both diseases intends to target the dynamic features of the endogenous intracellular suppressor cyclic AMP (cAMP). This review will summarize our current knowledge on cAMP and will emphasize on key discoveries and paradigm shifts reflecting the complex spatio-temporal nature of compartmentalized cAMP signalling networks in health and disease. As airway fibroblasts and airway smooth muscle cells are recognized as central players in the development and progression of asthma and COPD, we will focus on the role of cAMP signalling in their function in relation to airway function and plasticity. We will recapture on the recent identification of cAMP-sensing multi-protein complexes maintained by cAMP effectors, including A-kinase anchoring proteins (AKAPs), proteins kinase A (PKA), exchange protein directly activated by cAMP (Epac), cAMP-elevating seven-transmembrane (7TM) receptors and phosphodiesterases (PDEs) and we will report on findings indicating that the pertubation of compartmentalized cAMP signalling correlates with the pathopysiology of obstructive lung diseases. Future challenges include studies on cAMP dynamics and compartmentalization in the lung and the development of novel drugs targeting these systems for therapeutic interventions in chronic obstructive inflammatory diseases.
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Affiliation(s)
- Bart G J Dekkers
- Department of Molecular Pharmacology, University Center of Pharmacy, University of Groningen, The Netherlands.
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12
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Mosher AA, Rainey KJ, Giembycz MA, Wood S, Slater DM. Prostaglandin E2 represses interleukin 1 beta-induced inflammatory mediator output from pregnant human myometrial cells through the EP2 and EP4 receptors. Biol Reprod 2012; 87:7, 1-10. [PMID: 22517618 DOI: 10.1095/biolreprod.112.100099] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
Inflammatory mediators, including prostaglandins, cytokines, and chemokines, are strongly implicated in the mechanism of human labor, though their precise roles remain unknown. Here we demonstrate that interleukin 1 beta (IL-1beta) significantly increased the expression and release of interleukin-8 (CXCL8), monocyte chemotactic protein-1 (CCL2), and granulocyte macrophage colony-stimulating factor (CSF2) by primary human myometrial cells. However, this effect was repressed by prostaglandin E(2) (PGE(2)). As PGE(2) can activate four distinct PGE(2) receptors (EP(1), EP(2), EP(3), and EP(4)) to elicit various responses, we sought to define the EP receptor(s) responsible for this repression. Using selective EP receptor agonists and a selective EP(4) antagonist, we show that PGE(2) mediates the repression of IL-1beta-induced release of CXCL8, CCL2, and CSF2 via activation of the EP(2) and EP(4) receptors. The use of siRNA gene-specific knockdown further confirmed a role for both receptors. Real-time RT-PCR demonstrated that EP(2) was the most highly expressed of all four EP receptors at the mRNA level in human myometrial cells, and immunocytochemistry showed that EP(2) protein is abundantly present throughout the cells. Interestingly, PGE(2) does not appear to reduce mRNA expression of CXCL8, CCL2, and CSF2. Our results demonstrate that PGE(2) can elicit anti-inflammatory responses via activation of the EP(2) and EP(4) receptors in lower segment term pregnant human myometrial cells. Further elucidation of the EP receptor-mediated signaling pathways in the pregnant human uterus may be beneficial for optimizing the maintenance of pregnancy, induction of labor or indeed treatment of preterm labor.
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Affiliation(s)
- Andrea A Mosher
- Department of Physiology and Pharmacology, Faculty of Medicine, University of Calgary, Calgary, Alberta, Canada
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13
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Woodward DF, Jones RL, Narumiya S. International Union of Basic and Clinical Pharmacology. LXXXIII: classification of prostanoid receptors, updating 15 years of progress. Pharmacol Rev 2011; 63:471-538. [PMID: 21752876 DOI: 10.1124/pr.110.003517] [Citation(s) in RCA: 321] [Impact Index Per Article: 24.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
It is now more than 15 years since the molecular structures of the major prostanoid receptors were elucidated. Since then, substantial progress has been achieved with respect to distribution and function, signal transduction mechanisms, and the design of agonists and antagonists (http://www.iuphar-db.org/DATABASE/FamilyIntroductionForward?familyId=58). This review systematically details these advances. More recent developments in prostanoid receptor research are included. The DP(2) receptor, also termed CRTH2, has little structural resemblance to DP(1) and other receptors described in the original prostanoid receptor classification. DP(2) receptors are more closely related to chemoattractant receptors. Prostanoid receptors have also been found to heterodimerize with other prostanoid receptor subtypes and nonprostanoids. This may extend signal transduction pathways and create new ligand recognition sites: prostacyclin/thromboxane A(2) heterodimeric receptors for 8-epi-prostaglandin E(2), wild-type/alternative (alt4) heterodimers for the prostaglandin FP receptor for bimatoprost and the prostamides. It is anticipated that the 15 years of research progress described herein will lead to novel therapeutic entities.
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Affiliation(s)
- D F Woodward
- Dept. of Biological Sciences RD3-2B, Allergan, Inc., 2525 Dupont Dr., Irvine, CA 92612, USA.
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Clarke DL, Clifford RL, Jindarat S, Proud D, Pang L, Belvisi M, Knox AJ. TNFα and IFNγ synergistically enhance transcriptional activation of CXCL10 in human airway smooth muscle cells via STAT-1, NF-κB, and the transcriptional coactivator CREB-binding protein. J Biol Chem 2010; 285:29101-10. [PMID: 20833730 PMCID: PMC2937941 DOI: 10.1074/jbc.m109.0999952] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2009] [Revised: 07/02/2010] [Indexed: 01/14/2023] Open
Abstract
Asthmatic airway smooth muscle (ASM) expresses interferon-γ-inducible protein-10 (CXCL10), a chemokine known to mediate mast cell migration into ASM bundles that has been reported in the airways of asthmatic patients. CXCL10 is elevated in patients suffering from viral exacerbations of asthma and in patients with chronic obstructive pulmonary disease (COPD), diseases in which corticosteroids are largely ineffective. IFNγ and TNFα synergistically induce CXCL10 release from human ASM cells in a steroid-insensitive manner, via an as yet undefined mechanism. We report that TNFα activates the classical NF-κB (nuclear factor κB) pathway, whereas IFNγ activates JAK2/STAT-1α and that inhibition of the JAK/STAT pathway is more effective in abrogating CXCL10 release than the steroid fluticasone. The synergy observed with TNFα and IFNγ together, however, did not lie at the level of NF-κB activation, STAT-1α phosphorylation, or in vivo binding of these transcription factors to the CXCL10 promoter. Stimulation of human ASM cells with TNFα and IFNγ induced histone H4 but not histone H3 acetylation at the CXCL10 promoter, although no synergism was observed when both cytokines were combined. We show, however, that TNFα and IFNγ exert a synergistic effect on the recruitment of CREB-binding protein (CBP) to the CXCL10, which is accompanied by increased RNA polymerase II. Our results provide evidence that synergism between TNFα and IFNγ lies at the level of coactivator recruitment in human ASM and suggest that inhibition of JAK/STAT signaling may be of therapeutic benefit in steroid-resistant airway disease.
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Affiliation(s)
- Deborah L Clarke
- Nottingham Respiratory Biomedical Research Unit, City Hospital, University of Nottingham, Nottingham NG5 1PB, United Kingdom.
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Clarke DL, Clifford RL, Jindarat S, Proud D, Pang L, Belvisi M, Knox AJ. TNFα and IFNγ Synergistically Enhance Transcriptional Activation of CXCL10 in Human Airway Smooth Muscle Cells via STAT-1, NF-κB, and the Transcriptional Coactivator CREB-binding Protein. J Biol Chem 2010. [DOI: 10.1074/jbc.m109.099952] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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Hattori R, Shimizu S, Majima Y, Shimizu T. Prostaglandin E2 receptor EP2, EP3, and EP4 agonists inhibit antigen-induced mucus hypersecretion in the nasal epithelium of sensitized rats. Ann Otol Rhinol Laryngol 2009; 118:536-41. [PMID: 19708495 DOI: 10.1177/000348940911800714] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
OBJECTIVES Prostaglandin (PG) E2 is a potential anti-inflammatory mediator that attenuates airway inflammation. To elucidate the functions of the PGE2 receptors (EP1, EP2, EP3, and EP4) in allergic inflammation, we examined the in vivo effects of EP agonists on mucus hypersecretion and eosinophil infiltration in rat nasal epithelium. METHODS We induced hypertrophic and metaplastic changes in goblet cells in nasal epithelium of ovalbumin-sensitized rats by intranasal challenge with ovalbumin. The effects of subcutaneous injections of EP agonists on mucus production and eosinophil infiltration were examined. RESULTS The EP4 agonist (1 to 100 microg/kg) dose-dependently inhibited ovalbumin-induced mucus production. The EP2 and EP3 agonists (100 microg/kg) also significantly inhibited mucus production. The EP3 agonist inhibited antigen-induced eosinophil infiltration, whereas the EP1 agonist showed no effect. This suppression of mucus production by the EP4 agonist was only effective when the EP4 agonist was given in the effector phase; administration in the induction phase resulted in no effect. CONCLUSIONS These results indicate that PGE2 acts as an anti-inflammatory mediator via the EP receptors of airways in allergic inflammation. Selective EP agonists may provide a new therapeutic strategy for airway mucus hypersecretion.
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Affiliation(s)
- Reiko Hattori
- Department of Otorhinolaryngology--Head and Neck Surgery, Mie University School of Medicine, Tsu, Japan
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Maher SA, Birrell MA, Belvisi MG. Prostaglandin E2 mediates cough via the EP3 receptor: implications for future disease therapy. Am J Respir Crit Care Med 2009; 180:923-8. [PMID: 19729667 DOI: 10.1164/rccm.200903-0388oc] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
RATIONALE A significant population of patients with severe asthma and chronic obstructive pulmonary disease is less responsive to beta(2)-adrenoceptor agonists and corticosteroids, and there are possible safety issues concerning long-term use of these drugs. Inhaled prostaglandin E(2) (PGE(2)) is antiinflammatory and a bronchodilator in patients with asthma, but it also causes cough. OBJECTIVES We aimed to identify the receptor involved in PGE(2)-induced sensory nerve activation and cough using a range of in vitro and in vivo techniques. METHODS Depolarization of vagal sensory nerves (human, mouse, and guinea pig) was assessed as an indicator of sensory nerve acitivity. Cough was measured in a conscious guinea pig model. MEASUREMENTS AND MAIN RESULTS Using an extensive range of pharmacological tools, we identified that the EP(3) receptor mediates PGE(2)-induced depolarization of sensory nerves in human, mouse, and guinea pig. Further supporting evidence comes from data showing that responses to PGE(2) are virtually abolished in isolated vagus nerves from EP(3)-deficient mice (Ptger3(-/-)). Finally, we demonstrated the role of the EP(3) receptor in vivo using a selective EP(3) antagonist to attenuate PGE(2)-induced cough. CONCLUSIONS Identification of the receptor mediating PGE(2)-induced cough represents a key step in developing a drug that is antiinflammatory and a bronchodilator but without unwanted side effects.
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Affiliation(s)
- Sarah A Maher
- Respiratory Pharmacology, Airways Diseases, Imperial College London, Faculty of Medicine, National Heart and Lung Institute, Sir Alexander Fleming Building, London, SW7 2AZ, UK
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Sutcliffe AM, Clarke DL, Bradbury DA, Corbett LM, Patel JA, Knox AJ. Transcriptional regulation of monocyte chemotactic protein-1 release by endothelin-1 in human airway smooth muscle cells involves NF-kappaB and AP-1. Br J Pharmacol 2009; 157:436-50. [PMID: 19371341 DOI: 10.1111/j.1476-5381.2009.00143.x] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND AND PURPOSE Endothelin-1 (ET-1) is implicated in airway inflammation in asthma, but the mechanisms of its effects are poorly understood. We studied the effect of ET-1 on expression of the chemokine, monocyte chemotactic protein-1 (MCP-1), in primary cultures of human airway smooth muscle cells. EXPERIMENTAL APPROACH MCP-1 release was measured by elisa. Pharmacological antagonists/inhibitors, reverse transcriptase-polymerase chain reaction (RT-PCR) and Western blotting were used to study ET receptors and kinase cascades. Transcriptional regulation was studied by real-time RT-PCR, transient transfection studies and chromatin immunoprecipitation assay. Major findings were confirmed in cells from three donors and mechanistic studies in cells from one donor. KEY RESULTS ET-1 increased MCP-1 release through an ET(A) and ET(B) receptor-dependent mechanism. ET-1 increased MCP-1 mRNA levels but not mRNA stability suggesting it was acting transcriptionally. ET-1 increased the activity of an MCP-1 promoter-reporter construct. Serial deletions of the MCP-1 promoter mapped ET-1 effects to a region between -213 and -128 base pairs upstream of the translation start codon, containing consensus sequences for activator protein-1 (AP-1) and nuclear factor-kappaB (NF-kappaB). ET-1 promoted binding of AP-1 c-Jun subunit and NF-kappaB p65 subunit to the MCP-1 promoter. Blocking the inhibitor of kappaB kinase-2 with 2-[(aminocarbonyl)amino]-5-[4-fluorophenyl]-3-thiophenecarboxamide (TPCA-1) decreased ET-1-stimulated MCP-1 production. p38 and p44/p42 mitogen-activated protein kinases were involved in upstream signalling. CONCLUSIONS AND IMPLICATIONS ET-1 regulated MCP-1 transcriptionally, via NF-kappaB and AP-1. The upstream signalling involved ET(A), ET(B) receptors, p38 and p44/p42 mitogen-activated protein kinases. These may be targets for novel asthma therapies.
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Affiliation(s)
- Amy M Sutcliffe
- Nottingham Respiratory Biomedical Research Unit, University of Nottingham, City Hospital, Nottingham NG5 1PB, UK
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Dey I, Giembycz MA, Chadee K. Prostaglandin E(2) couples through EP(4) prostanoid receptors to induce IL-8 production in human colonic epithelial cell lines. Br J Pharmacol 2009; 156:475-85. [PMID: 19175605 DOI: 10.1111/j.1476-5381.2008.00056.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
BACKGROUND AND PURPOSE Prostaglandin (PG) E(2) and interleukin (IL)-8 are simultaneously increased during the inflammation that characterizes numerous pathologies such as inflammatory bowel disease. IL-8 is a potent neutrophil chemo-attractant and activator, and can initiate and/or exacerbate tissue injury. PGE(2) signals principally through prostanoid receptors of the EP(2) and/or EP(4) subtypes to promote cAMP-dependent cellular functions. The aim of this study was to identify the role of the EP(2) and EP(4) receptor subtype(s) on two human colonic epithelial cell lines (Caco-2 and T84), in regulating PGE(2)-induced IL-8 production. EXPERIMENTAL APPROACH To identify the causative receptor, we knocked-down and over-expressed EP(2) and EP(4) receptor subtypes in colonic epithelial cells and studied the effect of several selective EP(2)/EP(4) receptor agonists and antagonists. The inductions of IL-8 and EP receptor mRNA and protein expression were determined by real-time PCR and western blot analysis. The affinity of PGE(2) and Bmax values for the EP(2) and EP(4) receptor on colonic epithelial cells were determined by radioligand-binding assays with [(3)H]PGE(2). KEY RESULTS PGE(2) had the highest affinity for the EP(4) receptor subtype and promoted a robust stimulation of cAMP-dependent IL-8 synthesis. This effect was mimicked by a selective EP(4) receptor agonist, ONO-AE1-329, and abolished by silencing the EP(4) receptor gene by using siRNA techniques, a selective EP(4) receptor antagonist (ONO-AE3-208) and a selective inhibitor (Rp-cAMP) of cAMP-dependent protein kinase. CONCLUSIONS AND IMPLICATIONS These findings suggest that initiation and progression of colonic inflammation induced by IL-8 could be mediated, at least in part, by PGE(2) acting via the EP(4) receptor subtype.
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Affiliation(s)
- I Dey
- Departments of Microbiology and Infectious Diseases, Health Sciences Centre, University of Calgary, AB, Canada
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Clarke DL, Dakshinamurti S, Larsson AK, Ward JE, Yamasaki A. Lipid metabolites as regulators of airway smooth muscle function. Pulm Pharmacol Ther 2008; 22:426-35. [PMID: 19114116 DOI: 10.1016/j.pupt.2008.12.003] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2008] [Revised: 11/18/2008] [Accepted: 12/10/2008] [Indexed: 02/02/2023]
Abstract
Compelling evidence identifies airway smooth muscle (ASM) not only as a target but also a cellular source for a diverse range of mediators underlying the processes of airway narrowing and airway hyperresponsiveness in diseases such as asthma. These include the growing family of plasma membrane phospholipid-derived polyunsaturated fatty acids broadly characterised by the prostaglandins, leukotrienes, lipoxins, isoprostanes and lysophospholipids. In this review, we describe the enzymatic and non-enzymatic biosynthetic pathways of these lipid mediators and how these are influenced by drug treatment, oxidative stress and airways disease. Additionally, we outline their cognate receptors, many of which are expressed by ASM. We describe potential deleterious and protective roles for these lipid mediators in airway inflammatory and remodelling processes by describing their effects on diverse functions of ASM in asthma that have the potential to contribute to asthma pathogenesis and symptoms. These functions include contractile tone development, cytokine and extracellular matrix production, and cellular proliferation and migration.
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Affiliation(s)
- Deborah L Clarke
- Respiratory Pharmacology, National Heart and Lung Institute, Imperial College, London, UK
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Ammit AJ, Burgess JK, Hirst SJ, Hughes JM, Kaur M, Lau JY, Zuyderduyn S. The effect of asthma therapeutics on signalling and transcriptional regulation of airway smooth muscle function. Pulm Pharmacol Ther 2008; 22:446-54. [PMID: 19022391 DOI: 10.1016/j.pupt.2008.10.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/07/2008] [Revised: 10/02/2008] [Accepted: 10/22/2008] [Indexed: 01/11/2023]
Abstract
SCOPE OF THE REVIEW Our knowledge of the multifunctional nature of airway smooth muscle (ASM) has expanded rapidly in the last decade, but the underlying molecular mechanisms and how current therapies for obstructive airway diseases, such as asthma and chronic obstructive pulmonary disease (COPD), affect these are still being elucidated. Our current knowledge has built on the pharmacology of human ASM contraction and relaxation established prior to that and which is reviewed in detail elsewhere in this issue. The advent of methods to isolate and culture ASM cells, especially human ASM cells, has made it possible to study how they may contribute to airway remodelling through their synthetic, proliferative, and migratory capacities. Now the underlying molecular mechanisms of ASM growth factor secretion, extracellular matrix (ECM) production, proliferation and migration, as well as contraction and relaxation, are being determined. A complex network of signalling pathways leading to gene transcription in ASM cells permits this functional plasticity in healthy and diseased airways. This review is an overview of the effects of current therapies, and some of those in development, on key signalling pathways and transcription factors involved in these ASM functions.
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Affiliation(s)
- Alaina J Ammit
- Respiratory Research Group, Faculty of Pharmacy, University of Sydney, NSW, Australia.
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Clarke DL, Sutcliffe A, Deacon K, Bradbury D, Corbett L, Knox AJ. PKCβΙΙ Augments NF-κB-Dependent Transcription at the CCL11 Promoter via p300/CBP-Associated Factor Recruitment and Histone H4 Acetylation. THE JOURNAL OF IMMUNOLOGY 2008; 181:3503-14. [DOI: 10.4049/jimmunol.181.5.3503] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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McCahill A, Campbell L, McSorley T, Sood A, Lynch MJ, Li X, Yan C, Baillie GS, Houslay MD. In cardiac myocytes, cAMP elevation triggers the down-regulation of transcripts and promoter activity for cyclic AMP phosphodiesterase-4A10 (PDE4A10). Cell Signal 2008; 20:2071-83. [PMID: 18721873 DOI: 10.1016/j.cellsig.2008.07.017] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2008] [Accepted: 07/28/2008] [Indexed: 12/11/2022]
Abstract
Transcripts for the PDE4A10 cyclic AMP phosphodiesterase isoform are present in a wide variety of rat tissues including the heart. Sequence comparisons between the putative human and mouse promoters revealed a number of conserved regions including both an Sp1 and a CREB-binding site. The putative mouse PDE4A10 promoter was amplified from genomic DNA and sub-cloned into a luciferase reporter vector for investigation of activity in neonatal cardiac myocytes. Transfection with this construct identified a high level of luciferase expression in neonatal cardiac myocytes. Surprisingly, this activity was down-regulated by elevation of intracellular cAMP through a process involving PKA, but not EPAC, signalling. Such inhibition of the rodent PDE4A10 promoter activity in response to elevated cAMP levels is in contrast to the PDE4 promoters so far described. Site-directed mutagenesis revealed that the Sp1 binding site at promoter position -348 to -336 is responsible for the basal constitutive expression of murine PDE4A10. The conserved CREB-binding motif at position -370 to -363 also contributes to basal promoter activity but does not in itself confer cAMP inhibition upon the PDE4A10 promoter. EMSA analysis confirmed the authenticity of CREB and Sp1 binding sites. The transcriptional start site was identified to be an adenine residue at position -55 in the mouse PDE4A10 promoter. We present evidence that this novel down-regulation of PDE4A10 is mediated by the transcription factor ICER in a PKA dependent manner. The pool of cAMP in cardiac myocytes that down-regulates PDE4A10 is regulated by beta-adrenoceptor coupled adenylyl cyclase activity and via hydrolysis determined predominantly by the action of PDE4 (cAMP phosphodiesterase-4) and not PDE3 (cAMP phosphodiesterase-3). We suggest that increased cAMP may remodel cAMP-mediated signalling events by not only increasing the expression of specific PDE4 cAMP phosphodiesterases but also by down-regulating specific isoforms, such as is shown here for PDE4A10 in cardiac myocytes.
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Affiliation(s)
- Angela McCahill
- Neuroscience and Molecular Pharmacology, Wolfson Link and Davidson Buildings, Faculty of Biomedical & Life Sciences, University of Glasgow, University Avenue, Glasgow G12 8QQ, Scotland, UK
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Kaur M, Holden NS, Wilson SM, Sukkar MB, Chung KF, Barnes PJ, Newton R, Giembycz MA. Effect of beta2-adrenoceptor agonists and other cAMP-elevating agents on inflammatory gene expression in human ASM cells: a role for protein kinase A. Am J Physiol Lung Cell Mol Physiol 2008; 295:L505-14. [PMID: 18586957 DOI: 10.1152/ajplung.00046.2008] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
In diseases such as asthma, airway smooth muscle (ASM) cells play a synthetic role by secreting inflammatory mediators such as granulocyte-macrophage colony-stimulating factor (GM-CSF), IL-6, or IL-8 and by expressing surface adhesion molecules, including ICAM-1. In the present study, PGE(2), forskolin, and short-acting (salbutamol) and long-acting (salmeterol and formoterol) beta(2)-adrenoceptor agonists reduced the expression of ICAM-1 and the release of GM-CSF evoked by IL-1beta in ASM cells. IL-1beta-induced IL-8 release was also repressed by PGE(2) and forskolin, whereas the beta(2)-adrenoceptor agonists were ineffective. In each case, repression of these inflammatory indexes was prevented by adenoviral overexpression of PKIalpha, a highly selective PKA inhibitor. These data indicate a PKA-dependent mechanism of repression and suggest that agents that elevate intracellular cAMP, and thereby activate PKA, may have a widespread anti-inflammatory effect in ASM cells. Since ICAM-1 and GM-CSF are highly NF-kappaB-dependent genes, we used an adenoviral-delivered NF-kappaB-dependent luciferase reporter to examine the effects of forskolin and the beta(2)-adrenoceptor agonists on NF-kappaB activation. There was no effect on luciferase activity measured in the presence of forskolin or beta(2)-adrenoceptor agonists. This finding is consistent with the observation that IL-1beta-induced expression of IL-6, a known NF-kappaB-dependent gene in ASM, was also unaffected by beta(2)-adrenoceptor agonists, forskolin, PGE(2), 8-bromo-cAMP, or rolipram. Collectively, these results indicate that repression of IL-1beta-induced ICAM-1 expression and GM-CSF release by cAMP-elevating agents, including beta(2)-adrenoceptor agonists, may not occur through a generic effect on NF-kappaB.
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Affiliation(s)
- Manminder Kaur
- Dept. of Cell Biology & Anatomy, Faculty of Medicine, Univ. of Calgary, 3330 Hospital Dr. NW, Calgary, AB, Canada T2N 4N1
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Shimizu T, Hattori R, Shimizu S, Kouzaki H, Majima Y. Role of prostaglandin E2as a protective mediator for airway inflammation. ACTA ACUST UNITED AC 2007. [DOI: 10.1111/j.1365-2222.2007.00123.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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Li L, Kashleva H, Dongari-Bagtzoglou A. Cytotoxic and cytokine-inducing properties of Candida glabrata in single and mixed oral infection models. Microb Pathog 2007; 42:138-47. [PMID: 17306958 PMCID: PMC1973167 DOI: 10.1016/j.micpath.2006.12.003] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2006] [Revised: 12/12/2006] [Accepted: 12/14/2006] [Indexed: 11/26/2022]
Abstract
Oral candidiasis is a common opportunistic infection, with Candida albicans being the most prevalent etiologic agent and Candida glabrata emerging as an important pathogen. C. glabrata is frequently co-isolated with C. albicans from oral lesions. Although C. albicans has been shown to trigger significant cytokine responses and cell damage, C. glabrata has not been systematically studied yet. The purpose of this study was to characterize the ability of C. glabrata to induce proinflammatory cytokine responses and host damage as a single infecting organism and in combination with C. albicans, using in vitro models of the oral mucosa. In monolayer oral epithelial cell cultures, C. glabrata failed to induce a significant interleukin-1alpha and interleukin-8 cytokine response and showed lower cytotoxicity, compared to C. albicans. However, C. glabrata triggered a significantly higher granulocyte macrophage colony stimulating factor response than C. albicans. C. glabrata strains showed a strain-dependent tissue damaging ability and a superficial invasion of the mucosal compartment in a three-dimensional (3-D) in vitro model of the human oral mucosa and submucosa. In the 3-D system, co-infection failed to promote host damage beyond the levels of infection with C. albicans alone. These studies indicate that C. glabrata induces cytokines in human oral epithelium in a strain-specific manner, but its tissue/cell damaging ability, compared to C. albicans, is low. Synergy between C. glabrata and C. albicans in cytokine induction and host damage was not observed with the strains tested.
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Affiliation(s)
| | | | - Anna Dongari-Bagtzoglou
- Correspondence: Anna Dongari-Bagtzoglou, University of Connecticut, School of Dental Medicine, Department of Periodontology, 263 Farmington Ave, Farmington, CT 06030-1710, Tel: 860-679-4543, Fax: 860-679-1673, E-mail:
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Zhang G, Lee LY. Prostaglandin E2 enhances the sensitizing effect of hyperthermia on pulmonary C-fibers in rats. Respir Physiol Neurobiol 2006; 156:241-9. [PMID: 17161661 PMCID: PMC4445127 DOI: 10.1016/j.resp.2006.11.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2006] [Revised: 11/03/2006] [Accepted: 11/06/2006] [Indexed: 11/29/2022]
Abstract
This study was carried out to investigate whether the pulmonary C-fiber hypersensitivity induced by hyperthermia is altered by prostaglandin E(2) (PGE(2)). Single-unit afferent activities of pulmonary C-fibers were recorded in anesthetized, artificially ventilated rats when the intrathoracic temperature (T(it)) was maintained at normal (N; approximately 36 degrees C) and hyperthermia levels (H; approximately 41 degrees C) by perfusion of heated saline into the thoracic chamber for 3min. After approximately 20min of recovery, the fiber activities were recorded again during infusion of PGE(2) at both N and H levels of T(it). Our study showed: (1) The baseline fiber activity and responses to lung inflation, right-atrial injection of capsaicin and adenosine were all increased by increasing T(it) from N to H, and these hyperthermia-induced increases in sensitivities were also significantly augmented by PGE(2). (2) These enhanced sensitivities induced by PGE(2) were abolished by pretreatment with AH6809 and AH23848, selective antagonists of EP(2) and EP(4) prostanoid receptors, respectively. In conclusion, the hyperthermia-induced hypersensitivity of vagal pulmonary C-fibers is potentiated by PGE(2), and this effect is mediated through activation of EP(2) and EP(4) prostanoid receptors.
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MESH Headings
- Anesthesia
- Animals
- Biphenyl Compounds/pharmacology
- Body Temperature/drug effects
- Body Temperature/physiology
- Dinoprostone/pharmacology
- Fever/pathology
- In Vitro Techniques
- Infusions, Intravenous
- Lung/pathology
- Male
- Nerve Fibers, Unmyelinated/pathology
- Neurons, Afferent/pathology
- Pneumonia/pathology
- Rats
- Rats, Sprague-Dawley
- Receptors, Prostaglandin E/antagonists & inhibitors
- Receptors, Prostaglandin E, EP2 Subtype
- Receptors, Prostaglandin E, EP4 Subtype
- Respiration, Artificial
- Xanthones/pharmacology
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Affiliation(s)
- Guangfan Zhang
- Department of Physiology, University of Kentucky Medical Center, Lexington, KY 40536-0298, USA.
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Kay LJ, Yeo WW, Peachell PT. Prostaglandin E2 activates EP2 receptors to inhibit human lung mast cell degranulation. Br J Pharmacol 2006; 147:707-13. [PMID: 16432506 PMCID: PMC1751511 DOI: 10.1038/sj.bjp.0706664] [Citation(s) in RCA: 93] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
The prostanoid, PGE2, is known to inhibit human lung mast cell activity. The aim of the present study was to characterize the EP receptor that mediates this effect. PGE2 (pEC(50), 5.8+/-0.1) inhibited the IgE-mediated release of histamine from mast cells in a concentration-dependent manner. Alternative EP receptor agonists were studied. The EP2-selective agonist, butaprost (pEC50, 5.2+/-0.2), was an effective inhibitor of mediator release whereas the EP1/EP3 receptor agonist, sulprostone, and the EP1-selective agonist, 17-phenyl-trinor-PGE2, were ineffective. The DP agonist PGD2, the FP agonist PGF(2alpha), the IP agonist iloprost and the TP agonist U-46619 were ineffective inhibitors of IgE-mediated histamine release from mast cells. PGE2 induced a concentration-dependent increase in intracellular cAMP levels in mast cells. The effects of the EP1/EP2 receptor antagonist, AH6809, and the EP4 receptor antagonist, AH23848, on the PGE2-mediated inhibition of histamine release were determined. AH6809 (pK(B), 5.6+/-0.1) caused a modest rightward shift in the PGE2 concentration-response curve, whereas AH23848 was ineffective. Long-term (24 h) incubation of mast cells with either PGE2 or butaprost (EP2 agonist), but not sulprostone (EP1/EP3 agonist), caused a significant reduction in the subsequent ability of PGE2 to inhibit histamine release. Collectively, these data suggest that PGE2 mediates effects on human lung mast cells by interacting with EP2 receptors.
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Affiliation(s)
- Linda J Kay
- Molecular Pharmacology, University of Sheffield, The Royal Hallamshire Hospital (Floor M), Glossop Road, Sheffield, S Yorks S10 2JF
| | - Wilfred W Yeo
- Molecular Pharmacology, University of Sheffield, The Royal Hallamshire Hospital (Floor M), Glossop Road, Sheffield, S Yorks S10 2JF
| | - Peter T Peachell
- Molecular Pharmacology, University of Sheffield, The Royal Hallamshire Hospital (Floor M), Glossop Road, Sheffield, S Yorks S10 2JF
- Author for correspondence:
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30
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Seldon PM, Meja KK, Giembycz MA. Rolipram, salbutamol and prostaglandin E2 suppress TNFalpha release from human monocytes by activating Type II cAMP-dependent protein kinase. Pulm Pharmacol Ther 2006; 18:277-84. [PMID: 15777610 DOI: 10.1016/j.pupt.2004.12.012] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/04/2004] [Accepted: 12/21/2004] [Indexed: 11/18/2022]
Abstract
The extent to which cAMP-dependent protein kinase (PKA) mediates the inhibitory effects of cAMP-elevating drugs on tumour necrosis factor (TNF) alpha release from lipopolysaccharide (LPS)-stimulated human monocytes is equivocal. Here, we have investigated the role of this kinase by exploiting the ability of certain novel cAMP analogues to inhibit or activate PKA and the recently described cAMP-guanine nucleotide-exchange factors (GEFs). Pre-treatment of monocytes with Rp-8-Br-cAMPS, a selective inhibitor of Type I PKA that has no effect on basal or stimulated Rap1 (a downstream effector of cAMP-GEFs) activity, potentiated LPS-induced TNFalpha output but had little or no effect on the suppression of this cytokine effected by rolipram (a PDE4 inhibitor), prostaglandin (PG) E2 and salbutamol (a beta2-adrenoceptor agonist). In contrast, Rp-8-pCPT-cAMPS, which selectively blocks Type II PKA with only weak activity against Rap1, significantly antagonised or abolished the inhibitory effect of these cAMP-elevating agents. Pre-treatment of monocytes with 8-pCPT-2'-O-Me-cAMPS, a potent activator of cAMP-GEFs, failed to suppress TNFalpha output at concentrations known to profoundly activate Rap1. Collectively, these results indicate that cAMP-elevating drugs suppress TNFalpha release from LPS-stimulated human monocytes by activating PKA independently of cAMP-GEFs. Furthermore, by using phosphorothioate cAMP analogue PKA inhibitors we provide evidence that the Type II PKA isoenzyme is functionally the most important.
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Affiliation(s)
- Paul M Seldon
- Dermatology Section, Division of Medicine, Faculty of Medicine, Hammersmith Hospital, Imperial College London, DuCane Road, London W12 ONN, UK
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31
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Catley MC, Sukkar MB, Chung KF, Jaffee B, Liao SM, Coyle AJ, Haddad EB, Barnes PJ, Newton R. Validation of the anti-inflammatory properties of small-molecule IkappaB Kinase (IKK)-2 inhibitors by comparison with adenoviral-mediated delivery of dominant-negative IKK1 and IKK2 in human airways smooth muscle. Mol Pharmacol 2006; 70:697-705. [PMID: 16687566 DOI: 10.1124/mol.106.023150] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Asthma and chronic obstructive pulmonary disease (COPD) are characterized by chronic airway inflammation. However, because patients with COPD and certain patients with asthma show little or no therapeutic benefit from existing corticosteroid therapies, there is an urgent need for novel anti-inflammatory strategies. The transcription factor nuclear factor-kappaB (NF-kappaB) is central to inflammation and is necessary for the expression of numerous inflammatory genes. Proinflammatory cytokines, including interleukin (IL)-1beta and tumor necrosis factor (TNF)-alpha, activate the IkappaB kinase complex (IKK) to promote the degradation of inhibitory IkappaB proteins and activate NF-kappaB. This pathway and, in particular, the main IkappaB kinase, IKK2, are now considered prime targets for novel anti-inflammatory drugs. Therefore, we have used adenoviral overexpression to demonstrate NF-kappaB and IKK2 dependence of key inflammatory genes, including intercellular adhesion molecule (ICAM)-1, cyclooxygenase-2, IL-6, IL-8, granulocyte macrophage-colony-stimulating factor (GM-CSF), regulated on activation normal T cell expressed and secreted (RANTES), monocyte chemotactic protein-1 (MCP-1), growth-regulated oncogene-alpha (GROalpha), neutrophil-activating protein-2 (NAP-2), and epithelial neutrophil activating peptide 78 (ENA-78) in primary human airways smooth muscle cells. Because this cell type is central to the pathogenesis of airway inflammatory diseases, these data predict a beneficial effect of IKK2 inhibition. These validated outputs were therefore used to evaluate the novel IKK inhibitors N-(6-chloro-9H-beta-carbolin-8-yl) nicotinamide (PS-1145) and N-(6-chloro-7-methoxy-9H-beta-carbolin-8-yl)-2-methyl-nicotinamide (ML120B) on IL-1beta and TNFalpha-induced expression, and this was compared with the corticosteroid dexamethasone. As observed above, ICAM-1, IL-6, IL-8, GM-CSF, RANTES, MCP-1, GROalpha, NAP-2, and ENA-78 expression was reduced by the IKK inhibitors. Furthermore, this inhibition was either as effective, or for ICAM-1, MCP-1, GROalpha, and NAP-2, more effective, than a maximally effective concentration of dexamethasone. We therefore suggest that IKK inhibitors may be of considerable benefit in inflammatory airways diseases, particularly in COPD or severe asthma, in which corticosteroids are ineffective.
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Affiliation(s)
- Matthew C Catley
- National Heart and Lung Institute, Imperial College London, London, United Kingdom
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32
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Slater DM, Astle S, Woodcock N, Chivers JE, de Wit NCJ, Thornton S, Vatish M, Newton R. Anti-inflammatory and relaxatory effects of prostaglandin E2 in myometrial smooth muscle. Mol Hum Reprod 2006; 12:89-97. [PMID: 16455619 DOI: 10.1093/molehr/gal005] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The onset of human labour is complex and involves multiple mediators, prostaglandins, cytokines and chemokines. However, whilst prostaglandins are routinely used for labour induction and inhibitors of prostaglandin synthesis are used to prevent pre-term labour, these practices are not invariably successful, and the rationale for their use is equivocal. As COX-2 and prostaglandin E(2) (PGE(2)) production is increased towards term, we have investigated the effect of PGE(2) and other cAMP-elevating agents on events associated with labour induction. Time-dependent increases in granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin-8 (IL-8) release were observed following treatment of primary human myometrial smooth muscle (HMSM) cells with IL-1beta, via mechanisms that required de novo transcription and translation. Prior treatment with PGE(2) (1 microM) produced 86 and 80% decreases in GM-CSF and IL-8 release, respectively. Similarly, the cAMP analogue, 8-bromo-cAMP (8Br-cAMP) and the phosphodiesterase-4 (PDE(4)) inhibitor, rolipram, also repressed GM-CSF and IL-8 release. In addition, PGE(2), 8Br-cAMP, rolipram and salbutamol all had a dose-dependent inhibitory effect on spontaneous myometrial contractions in vitro. In this study, PGE(2) reduced the release of factors associated with cervical ripening and attenuated force development in myometrial smooth muscle, raising the possibility that in myometrium, PGE(2) may act to down-regulate some of the processes that contribute to the onset of human labour and may be beneficial in helping to maintain pregnancy towards term.
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Affiliation(s)
- Donna M Slater
- Department of Biological Sciences, Biomedical Research Institute, University of Warwick, Coventry, UK
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33
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Chorley BN, Li Y, Fang S, Park JA, Adler KB. (R)-albuterol elicits antiinflammatory effects in human airway epithelial cells via iNOS. Am J Respir Cell Mol Biol 2006; 34:119-27. [PMID: 16195534 PMCID: PMC2644187 DOI: 10.1165/rcmb.2005-0338oc] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2005] [Accepted: 09/19/2005] [Indexed: 12/28/2022] Open
Abstract
Catecholamines can suppress production of inflammatory mediators in different cell types, including airway epithelium, but downstream signaling mechanisms involved in regulation of these antiinflammatory effects are largely unknown. We theorized that acute beta2-adrenergic stimulation of airway epithelial cells with albuterol could suppress the production and release of inflammatory mediators, specifically granulocyte macrophage-colony stimulating factor (GM-CSF) via a pathway involving inducible nitric oxide synthase (iNOS). Normal human bronchial epithelial (NHBE) cells in primary culture were exposed to a cytokine mixture (10 ng/ml each IFN-gamma and IL-1beta) to induce iNOS expression. (R)- and (S)-enantiomers of albuterol, as well as racemic mixtures, were added with these cytokines, and effects on GM-CSF expression and production were assessed. Specific inhibitors and activators of protein kinases (PKs), beta2-adrenergic receptor antagonists, and small interfering RNAs against iNOS were used to delineate signaling pathways involved. iNOS message was significantly upregulated in a concentration-dependent manner by the active (R)-enantiomer of albuterol. (R)-albuterol also attenuated cytokine-induced increases in GM-CSF steady-state mRNA expression and protein release. The (S)-enantomer of albuterol had no effect on these parameters. PKC, specifically, the delta isoform, was required for iNOS message increase, but PKA and PKG were not involved in the pathway. Overall, this study identifies a novel pathway by which beta2-adrenergic agonists may exhibit antiinflammatory effects in airway epithelium and surrounding milieu.
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Affiliation(s)
- Brian N Chorley
- Department of Molecular Biomedical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC 27606, USA
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Mounkaïla B, Marthan R, Roux E. Biphasic effect of extracellular ATP on human and rat airways is due to multiple P2 purinoceptor activation. Respir Res 2005; 6:143. [PMID: 16336659 PMCID: PMC1325041 DOI: 10.1186/1465-9921-6-143] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2005] [Accepted: 12/08/2005] [Indexed: 11/10/2022] Open
Abstract
Background Extracellular ATP may modulate airway responsiveness. Studies on ATP-induced contraction and [Ca2+]i signalling in airway smooth muscle are rather controversial and discrepancies exist regarding both ATP effects and signalling pathways. We compared the effect of extracellular ATP on rat trachea and extrapulmonary bronchi (EPB) and both human and rat intrapulmonary bronchi (IPB), and investigated the implicated signalling pathways. Methods Isometric contraction was measured on rat trachea, EPB and IPB isolated rings and human IPB isolated rings. [Ca2+]i was monitored fluorimetrically using indo 1 in freshly isolated and cultured tracheal myocytes. Statistical comparisons were done with ANOVA or Student's t tests for quantitative variables and χ2 tests for qualitative variables. Results were considered significant at P < 0.05. Results In rat airways, extracellular ATP (10-6–10-3 M) induced an epithelium-independent and concentration-dependent contraction, which amplitude increased from trachea to IPB. The response was transient and returned to baseline within minutes. Similar responses were obtained with the non-hydrolysable ATP analogous ATP-γ-S. Successive stimulations at 15 min-intervals decreased the contractile response. In human IPB, the contraction was similar to that of rat IPB but the time needed for the return to baseline was longer. In isolated myocytes, ATP induced a concentration-dependent [Ca2+]i response. The contractile response was not reduced by thapsigargin and RB2, a P2Y receptor inhibitor, except in rat and human IPB. By contrast, removal of external Ca2+, external Na+ and treatment with D600 decreased the ATP-induced response. The contraction induced by α-β-methylene ATP, a P2X agonist, was similar to that induced by ATP, except in IPB where it was lower. Indomethacin and H-89, a PKA inhibitor, delayed the return to baseline in extrapulmonary airways. Conclusion Extracellular ATP induces a transient contractile response in human and rat airways, mainly due to P2X receptors and extracellular Ca2+ influx in addition with, in IPB, P2Y receptors stimulation and Ca2+ release from intracellular Ca2+ stores. Extracellular Ca2+ influx occurs through L-type voltage-dependent channels activated by external Na+ entrance through P2X receptors. The transience of the response cannot be attributed to ATP degradation but to purinoceptor desensitization and, in extrapulmonary airways, prostaglandin-dependent PKA activation.
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Affiliation(s)
- Boutchi Mounkaïla
- Laboratoire de Physiologie Cellulaire Respiratoire, Université Bordeaux 2, Bordeaux, F-33076 France; Inserm, E356, Bordeaux, F-33076 France
| | - Roger Marthan
- Laboratoire de Physiologie Cellulaire Respiratoire, Université Bordeaux 2, Bordeaux, F-33076 France; Inserm, E356, Bordeaux, F-33076 France
| | - Etienne Roux
- Laboratoire de Physiologie Cellulaire Respiratoire, Université Bordeaux 2, Bordeaux, F-33076 France; Inserm, E356, Bordeaux, F-33076 France
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35
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Chung KF. Evaluation of selective prostaglandin E2 (PGE2) receptor agonists as therapeutic agents for the treatment of asthma. Sci Signal 2005; 2005:pe47. [PMID: 16189372 DOI: 10.1126/stke.3032005pe47] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Prostaglandin E2 (PGE2) released in asthmatic airways has bronchodilator properties and inhibits allergen-induced bronchoconstriction and release of inflammatory mediators. Although considered as a potential treatment for asthma, PGE2 also has some proinflammatory properties. PGE2 acts through four different receptor subtypes (EP1, EP2, EP3, and EP4) that may explain some of PGE2's diverse effects. In a mouse model of allergic inflammation in which the four receptors were individually deleted, only EP3(-/-) mice showed an enhancement of inflammation, whereas an EP3 agonist was inhibitory, with PGE2 being inactive. Thus, EP3 agonists may lead to a new approach for the treatment of asthma. However, other PGE2 receptor subtypes may also have beneficial effects, and a greater understanding of the signaling pathways of these receptor subtypes will help to clarify the role of these receptors in asthma.
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Affiliation(s)
- K F Chung
- National Heart and Lung Institute, Imperial College London, London SW3 6LY, UK.
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36
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Birrell MA, Hardaker E, Wong S, McCluskie K, Catley M, De Alba J, Newton R, Haj-Yahia S, Pun KT, Watts CJ, Shaw RJ, Savage TJ, Belvisi MG. Ikappa-B kinase-2 inhibitor blocks inflammation in human airway smooth muscle and a rat model of asthma. Am J Respir Crit Care Med 2005; 172:962-71. [PMID: 16002568 DOI: 10.1164/rccm.200412-1647oc] [Citation(s) in RCA: 99] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
RATIONALE Nuclear factor (NF)-kappaB is a transcription factor known to regulate the expression of many inflammatory genes, including cytokines, chemokines, and adhesion molecules. NF-kappaB is held inactive in the cytoplasm, bound to I-kappaB. The removal of I-kappaB, via the actions of inhibitor of kappaB (I-kappaB) kinase-2 (IKK-2), allows NF-kappaB to enter the nucleus. OBJECTIVES To determine the impact of inhibiting IKK-2 on in vitro and in vivo models of airway inflammation. METHODS The effect of inhibiting IKK-2 was assessed in stimulated, cultured, primary human airway smooth muscle cells and an antigen-driven rat model of lung inflammation. MEASUREMENTS The release of cytokines from cultured cells and inflammatory cytokine expression and cellular burden in the lung were determined. MAIN RESULTS Two structurally distinct molecules and dominant negative technology demonstrated that inhibition of IKK-2 activity completely blocked cytokine release from cultured cells, whereas the two glucocorticoid comparators had limited impact on granulocyte colony-stimulating factor, interleukin 8, and eotaxin release. In addition, in an in vivo antigen-driven model of airway inflammation, the IKK-2 inhibitor blocked NF-kappaB nuclear translocation, which was associated with a reduction in inflammatory cytokine gene and protein expression, airway eosinophilia, and late asthmatic reaction, similar in magnitude to that obtained with budesonide. CONCLUSION This study demonstrates that inhibiting IKK-2 results in a general reduction of the inflammatory response in vitro and in vivo. Compounds of this class could have therapeutic utility in the treatment of asthma and may, in certain respects, possess a beneficial efficacy profile compared with that of a steroid.
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Affiliation(s)
- Mark A Birrell
- Respiratory Pharmacology Group, National Heart and Lung Institute, Imperial College Faculty of Medicine, London, UK
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Clarke DL, Belvisi MG, Smith SJ, Hardaker E, Yacoub MH, Meja KK, Newton R, Slater DM, Giembycz MA. Prostanoid receptor expression by human airway smooth muscle cells and regulation of the secretion of granulocyte colony-stimulating factor. Am J Physiol Lung Cell Mol Physiol 2005; 288:L238-50. [PMID: 15640521 DOI: 10.1152/ajplung.00313.2004] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The prostanoid receptors on human airway smooth muscle cells (HASMC) that augment the release by IL-1β of granulocyte colony-stimulating factor (G-CSF) have been characterized and the signaling pathway elucidated. PCR of HASM cDNA identified products corresponding to EP2, EP3, and EP4receptor subtypes. These findings were corroborated at the protein level by immunocytochemistry. IL-1β promoted the elaboration of G-CSF, which was augmented by PGE2. Cicaprost (IP receptor agonist) was approximately equiactive with PGE2, whereas PGD2, PGF2α, and U-46619 (TP receptor agonist) were over 10-fold less potent. Neither SQ 29,548 nor BW A868C (TP and DP1receptor antagonists, respectively) attenuated the enhancement of G-CSF release evoking any of the prostanoids studied. With respect to PGE2, the EP receptor agonists 16,16-dimethyl PGE2(nonselective), misoprostol (EP2/EP3selective), 17-phenyl-ω-trinor PGE2(EP1selective), ONO-AE1-259, and butaprost (both EP2selective) were full agonists at enhancing G-CSF release. AH 6809 (10 μM) and L-161,982 (2 μM), which can be used in HASMC as selective EP2and EP4receptor antagonists, respectively, failed to displace to the right the PGE2concentration-response curve that described the augmented G-CSF release. In contrast, AH 6809 and L-161,982 in combination competitively antagonized PGE2-induced G-CSF release. Augmentation of G-CSF release by PGE2was mimicked by 8-BrcAMP and abolished in cells infected with an adenovirus vector encoding an inhibitor protein of cAMP-dependent protein kinase (PKA). These data demonstrate that PGE2facilitates G-CSF secretion from HASMC through a PKA-dependent mechanism by acting through EP2and EP4prostanoid receptors and that effective antagonism is realized only when both subtypes are blocked concurrently.
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Affiliation(s)
- Deborah L Clarke
- Thoraic Medicine, National Heart and Lung Institute, Imperial College London, London, UK
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Clarke DL, Belvisi MG, Hardaker E, Newton R, Giembycz MA. E-ring 8-isoprostanes are agonists at EP2- and EP4-prostanoid receptors on human airway smooth muscle cells and regulate the release of colony-stimulating factors by activating cAMP-dependent protein kinase. Mol Pharmacol 2004; 67:383-93. [PMID: 15528403 DOI: 10.1124/mol.104.006486] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
8-Isoprostanes are bioactive lipid mediators formed via the nonenzymatic peroxidation of arachidonic acid by free radicals and reactive oxygen species. However, their cognate receptors, biological actions, and signaling pathways are poorly studied. Here, we report the effect of a variety of E- and Falpha-ring 8-isoprostanes on the release of granulocyte/macrophage colony-stimulating factor (GM-CSF) and granulocyte colony-stimulating factor (G-CSF) from human airway smooth muscle (HASM) cells stimulated with interleukin-1beta (IL-1beta). The elaboration of GM-CSF and G-CSF by IL-1beta was inhibited and augmented, respectively, in a concentration-dependent manner by 8-iso-prostaglandin (PG) E(1) and 8-iso-PGE(2), but not by 8-iso-PGF(1alpha), 8-iso-PGF(2alpha), and 8-iso-PGF(3)alpha. AH 6809 (6-isopropoxy-9-oxoxanthine-2-carboxylic acid), an EP(1)-/EP(2)-/DP-receptor blocking drug, antagonized the inhibitory effect of 8-iso-PGE(1) and 8-iso-PGE(2) on GM-CSF output with an affinity consistent with an interaction at prostanoid receptors of the EP(2)-subtype. In contrast, the facilitation by 8-iso-PGE(1) and 8-iso-PGE(2) of G-CSF release was unaffected by AH 6809 and the selective EP(4)-receptor antagonist L-161,982 [4'-[3-butyl-5-oxo-1-(2-trifluoromethyl-phenyl)-1,5-dihydro-[1,2,4]triazol-4-ylmethyl]-biphenyl-2-sulfonic acid (3-methyl-thiophene-2-carbonyl)-amide]. However, when used in combination, AH 6809 and L-161,982 displaced 5-fold to the right the 8-iso-PGE and 8-iso-PGE concentration-response curves. The opposing (1)effect of E-ring (2)8-isoprostanes on GM-CSF and G-CSF release was mimicked by 8-bromo-cAMP and abolished in cells infected with an adenovirus vector encoding an inhibitor protein of cAMP-dependent protein kinase (PKA). Together, these data demonstrate that E-ring 8-isoprostanes regulate the secretion of GM-CSF and G-CSF from HASM cells by a cAMP- and PKA-dependent mechanism. Moreover, antagonist studies revealed that 8-iso-PGE(1) and 8-iso-PGE(2) act solely via EP(2) -receptors to inhibit GM-CSF release, whereas both EP(2)- and EP(4)-receptor subtypes positively regulate G-CSF output.
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MESH Headings
- Adolescent
- Adult
- Cells, Cultured
- Colony-Stimulating Factors/metabolism
- Cyclic AMP-Dependent Protein Kinases/metabolism
- Dinoprost/analogs & derivatives
- Dinoprost/chemistry
- Dinoprost/pharmacology
- Dose-Response Relationship, Drug
- Enzyme Activation/drug effects
- Enzyme Activation/physiology
- Female
- Humans
- Male
- Middle Aged
- Myocytes, Smooth Muscle/drug effects
- Myocytes, Smooth Muscle/metabolism
- Receptors, Prostaglandin E/agonists
- Receptors, Prostaglandin E/metabolism
- Receptors, Prostaglandin E/physiology
- Receptors, Prostaglandin E, EP2 Subtype
- Receptors, Prostaglandin E, EP4 Subtype
- Trachea/drug effects
- Trachea/metabolism
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Affiliation(s)
- Deborah L Clarke
- Thoraic Medicine, National Heart and Lung Institute, Imperial College London, London, UK
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