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Hamed O, Jayasinghe V, Giembycz MA. The β-Blocker Carvedilol and Related Aryloxypropanolamines Promote ERK1/2 Phosphorylation in HEK293 Cells with K A Values Distinct From Their Equilibrium Dissociation Constants as β 2-Adrenoceptor Antagonists: Evidence for Functional Affinity. J Pharmacol Exp Ther 2024; 388:688-700. [PMID: 38129128 DOI: 10.1124/jpet.123.001920] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Revised: 11/06/2023] [Accepted: 11/13/2023] [Indexed: 12/23/2023] Open
Abstract
The determination of affinity by using functional assays is important in drug discovery because it provides a more relevant estimate of the strength of interaction of a ligand to its cognate receptor than radioligand binding. However, empirical evidence for so-called, "functional affinity" is limited. Herein, we determined whether the affinity of carvedilol, a β-adrenoceptor antagonist used to treat heart failure that also promotes extracellular signal-regulated kinases 1 and 2 (ERK1/2) phosphorylation, differed between these two pharmacological activities. Four structurally related β-adrenoceptor antagonists (alprenolol, carazolol, pindolol, propranolol) that also activated ERK1/2 were included as comparators to enhance our understanding of how these drugs work in the clinical setting. In HEK293 cells stably expressing the human β 2-adrenoceptor carvedilol and related aryloxypropanolamines were partial agonists of ERK1/2 phosphorylation with potencies ([A]50s) that were lower than their equilibrium dissociation constants (K Bs) as β 2-adrenoceptor antagonists. As the [A]50 of a partial agonist is a good approximation of its K B, then these data indicated that the affinities of carvedilol and related ligands for these two activities were distinct. Moreover, there was a significant negative rank order correlation between the [A]50 of each ligand to activate ERK1/2 and their intrinsic activities (i.e., as intrinsic activity for ERK1/2 phosphorylation increased, so did affinity). Genome editing revealed that the transducer that coupled the β 2-adrenoceptor to ERK1/2 phosphorylation in response to carvedilol and other β 2-adrenoceptor antagonists was Gαs. Collectively, these data support the concept of "functional affinity" and indicate that the ability of the β 2-adrenoceptor to recruit Gαs may influence the affinity of the activating ligand. SIGNIFICANCE STATEMENT: In HEK293 cells overexpressing the human β2-adrenoceptor carvedilol and four related aryloxypropanolamines behaved as β2-adrenoceptor antagonists and partial agonists of ERK1/2 phosphorylation with rank orders of affinity that were distinct. These data imply that carvedilol and other β-blockers can stabilize the β2-adrenoceptor in different affinity conformations that are revealed when functionally distinct responses are measured. This is the basis for the pharmacological concept of "functional affinity."
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Affiliation(s)
- Omar Hamed
- Lung Health Research Group, Department of Physiology and Pharmacology, Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Varuna Jayasinghe
- Lung Health Research Group, Department of Physiology and Pharmacology, Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Mark A Giembycz
- Lung Health Research Group, Department of Physiology and Pharmacology, Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
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Hamed O, Joshi R, Mostafa MM, Giembycz MA. α and β Catalytic Subunits of cAMP-dependent Protein Kinase Regulate Formoterol-induced Inflammatory Gene Expression Changes in Human Bronchial Epithelial Cells. Br J Pharmacol 2022; 179:4593-4614. [PMID: 35735057 DOI: 10.1111/bph.15901] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Revised: 04/27/2022] [Accepted: 06/18/2022] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND & PURPOSE It has been proposed that genomic mechanisms contribute to the adverse-effects that are often experienced by asthmatic subjects who take regular, inhaled β2 -adrenoceptor agonists as a monotherapy. Moreover, data from preclinical models of asthma suggest that these gene expression changes are mediated by β-arrestin-2 rather than PKA. Herein, we tested this hypothesis by comparing the genomic effects of formoterol, a β2 -adrenoceptor agonist, with forskolin in human primary bronchial epithelial cells (HBEC). EXPERIMENTAL APPROACH Gene expression changes were determined by RNA-sequencing. Gene silencing and genome editing were employed to explore the roles of β-arrestin-2 and PKA. KEY RESULTS The formoterol-regulated transcriptome in HBEC treated concurrently with TNFα, was defined by 1480 unique gene expression changes. TNFα-induced transcripts modulated by formoterol were annotated with enriched gene ontology terms related to inflammation and proliferation, notably "GO:0070374~positive regulation of ERK1 and ERK2 cascade", which is an established β-arrestin-2 target. However, expression of the formoterol- and forskolin-regulated transcriptomes were highly rank-order correlated and the effects of formoterol on TNFα-induced inflammatory genes were abolished by an inhibitor of PKA. Furthermore, formoterol-induced gene expression changes in BEAS-2B bronchial epithelial cell clones deficient in β-arrestin-2 were comparable to those expressed by their parental counterparts. Contrariwise, gene expression was partially inhibited in clones lacking the α-catalytic subunit (Cα) of PKA and abolished following the additional knockdown of the β-catalytic subunit (Cβ) paralogue. CONCLUSIONS The effects of formoterol on inflammatory gene expression in airway epithelia are mediated by PKA and involve the cooperation of PKA-Cα and PKA-Cβ.
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Affiliation(s)
- Omar Hamed
- Airways Inflammation Research Group, Department of Physiology & Pharmacology, Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Radhika Joshi
- Airways Inflammation Research Group, Department of Physiology & Pharmacology, Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Mahmoud M Mostafa
- Airways Inflammation Research Group, Department of Physiology & Pharmacology, Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Mark A Giembycz
- Airways Inflammation Research Group, Department of Physiology & Pharmacology, Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
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Hamed O, Giembycz MA. Differential Roles of the α and β Catalytic Subunits of PKA in the Regulation of Formoterol‐modulated Gene Expression Changes in Human Airway Epithelial Cells. FASEB J 2022. [DOI: 10.1096/fasebj.2022.36.s1.r4247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Omar Hamed
- Pharmacology and PhysiologyCumming School of Medicine ‐ University of CalgaryCalgaryAB
| | - Mark A. Giembycz
- Pharmacology and PhysiologyCumming School of Medicine ‐ University of CalgaryCalgaryAB
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Hamed O, Joshi R, Michi AN, Kooi C, Giembycz MA. β 2-Adrenoceptor Agonists Promote ERK1/2 Dephosphorylation in Human Airway Epithelial Cells by Canonical, cAMP-driven Signaling Independently of β-Arrestin 2. Mol Pharmacol 2021; 100:388-405. [PMID: 34341099 DOI: 10.1124/molpharm.121.000294] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Accepted: 07/07/2021] [Indexed: 11/22/2022] Open
Abstract
Chronic use of β2-adrenoceptor agonists as a monotherapy in asthma is associated with a loss of disease control and an increased risk of mortality. Herein, we tested the hypothesis that β2-adrenoceptor agonists, including formoterol, promote biased, β-arrestin 2 (βArr2)-dependent activation of the mitogen-activated protein (MAP) kinases, ERK1/2, in human airway epithelial cells and, thereby, effect changes in gene expression that could contribute to their adverse clinical outcomes. Three airway epithelial cell models were used: the BEAS-2B cell line, human primary bronchial epithelial cells (HBEC) grown in submersion culture and HBEC that were highly differentiated at an air-liquid interface. Unexpectedly, treatment of all epithelial cell models with formoterol decreased basal ERK1/2 phosphorylation. This was mediated by cAMP-dependent protein kinase and involved the inactivation of C-rapidly-activated fibrosarcoma, which attenuated down-stream ERK1/2 activity, and the induction of dual-specificity phosphatase-1. Formoterol also inhibited the basal expression of early growth response-1, an ERK1/2-regulated gene that controls cell growth and repair in the airways. Neither carvedilol, a β2-adrenoceptor agonist biased towards βArr2, nor formoterol promoted ERK1/2 phosphorylation in BEAS-2B cells although β2-adrenoceptor desensitization was compromised in ARRB2-deficient cells. Collectively, these results contest the hypothesis that formoterol activates ERK1/2 in airway epithelia by nucleating a βArr2 signaling complex; instead, they indicate that β2-adrenoceptor agonists inhibit constitutive ERK1/2 activity in a cAMP-dependent manner. These findings are the antithesis of results obtained using acutely challenged native and engineered HEK293 cells, which have been used extensively to study mechanisms of ERK1/2 activation, and highlight the cell-type-dependence of β2-adrenoceptor-mediated signaling. Significance Statement It has been proposed that the adverse-effects of β2-adrenoceptor agonist monotherapy in asthma are mediated by genomic mechanisms that occur principally in airway epithelial cells and are the result of β-arrestin 2-dependent activation of ERK1/2. This study shows that β2-adrenoceptor agonists, paradoxically, reduced ERK1/2 phosphorylation in airway epithelia by disrupting upstream Ras-C-Raf complex formation and inducing DUSP1. Moreover, these effects were PKA-dependent suggesting that β2-adrenoceptor agonists were not biased toward β-arrestin 2 and acted via canonical, cAMP-dependent signaling.
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Affiliation(s)
- Omar Hamed
- Physiology & Pharmacology, University of Calgary, Canada
| | - Radhika Joshi
- Physiology & Pharmacology, University of Calgary, Canada
| | - Aubrey N Michi
- Physiology & Pharmacology, University of Calgary, Canada
| | - Cora Kooi
- Physiology & Pharmacology, University of Calgary, Canada
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Mostafa MM, Rider CF, Wathugala ND, Leigh R, Giembycz MA, Newton R. Transcriptome-Level Interactions between Budesonide and Formoterol Provide Insight into the Mechanism of Action of Inhaled Corticosteroid/Long-Acting β 2-Adrenoceptor Agonist Combination Therapy in Asthma. Mol Pharmacol 2020; 99:197-216. [PMID: 33376135 DOI: 10.1124/molpharm.120.000146] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2020] [Accepted: 12/07/2020] [Indexed: 12/26/2022] Open
Abstract
In 2019, the Global Initiative for Asthma treatment guidelines were updated to recommend that inhaled corticosteroid (ICS)/long-acting β 2-adrenoceptor agonist (LABA) combination therapy should be a first-in-line treatment option for asthma. Although clinically superior to ICS, mechanisms underlying the efficacy of this combination therapy remain unclear. We hypothesized the existence of transcriptomic interactions, an effect that was tested in BEAS-2B and primary human bronchial epithelial cells (pHBECs) using formoterol and budesonide as representative LABA and ICS, respectively. In BEAS-2B cells, formoterol produced 267 (212 induced; 55 repressed) gene expression changes (≥2/≤0.5-fold) that were dominated by rapidly (1 to 2 hours) upregulated transcripts. Conversely, budesonide induced 370 and repressed 413 mRNAs, which occurred predominantly at 6-18 hours and was preceded by transcripts enriched in transcriptional regulators. Significantly, genes regulated by both formoterol and budesonide were over-represented in the genome; moreover, budesonide plus formoterol induced and repressed 609 and 577 mRNAs, respectively, of which ∼one-third failed the cutoff criterion for either treatment alone. Although induction of many mRNAs by budesonide plus formoterol was supra-additive, the dominant (and potentially beneficial) effect of budesonide on formoterol-induced transcripts, including those encoding many proinflammatory proteins, was repression. Gene ontology analysis of the budesonide-modulated transcriptome returned enriched terms for transcription, apoptosis, proliferation, differentiation, development, and migration. This "functional" ICS signature was augmented in the presence of formoterol. Thus, LABAs modulate glucocorticoid action, and comparable transcriptome-wide interactions in pHBECs imply that such effects may be extrapolated to individuals with asthma taking combination therapy. Although repression of formoterol-induced proinflammatory mRNAs should be beneficial, the pathophysiological consequences of other interactions require investigation. SIGNIFICANCE STATEMENT: In human bronchial epithelial cells, formoterol, a long-acting β 2-adrenoceptor agonist (LABA), enhanced the expression of inflammatory genes, and many of these changes were reduced by the glucocorticoid budesonide. Conversely, the ability of formoterol to enhance both gene induction and repression by budesonide provides mechanistic insight as to how adding a LABA to an inhaled corticosteroid may improve clinical outcomes in asthma.
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Affiliation(s)
- Mahmoud M Mostafa
- Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada
| | - Christopher F Rider
- Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada
| | - N Dulmini Wathugala
- Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada
| | - Richard Leigh
- Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada
| | - Mark A Giembycz
- Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada
| | - Robert Newton
- Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada
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Joshi R, Hamed O, Yan D, Michi AN, Mostafa MM, Wiehler S, Newton R, Giembycz MA. Prostanoid Receptors of the EP 4-Subtype Mediate Gene Expression Changes in Human Airway Epithelial Cells with Potential Anti-Inflammatory Activity. J Pharmacol Exp Ther 2020; 376:161-180. [PMID: 33158942 DOI: 10.1124/jpet.120.000196] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2020] [Accepted: 11/03/2020] [Indexed: 11/22/2022] Open
Abstract
There is a clear, unmet clinical need to identify new drugs to treat individuals with asthma, chronic obstructive pulmonary disease (COPD), and idiopathic pulmonary fibrosis (IPF) in whom current medications are either inactive or suboptimal. In preclinical models, EP4-receptor agonists display efficacy, but their mechanism of action is unclear. In this study, using human bronchial epithelial cells as a therapeutically relevant drug target, we hypothesized that changes in gene expression may play an important role. Several prostanoid receptor mRNAs were detected in BEAS-2B cells, human primary bronchial epithelial cells (HBECs) grown in submersion culture and HBECs grown at an air-liquid interface with PTGER4 predominating. By using the activation of a cAMP response element reporter in BEAS-2B cells as a surrogate of gene expression, Schild analysis determined that PTGER4 mRNAs encoded functional EP4-receptors. Moreover, inhibitors of phosphodiesterase 4 (roflumilast N-oxide [RNO]) and cAMP-dependent protein kinase augmented and attenuated, respectively, reporter activation induced by 2-[3-[(1R,2S,3R)-3-hydroxy-2-[(E,3S)-3-hydroxy-5-[2-(methoxymethyl)phenyl]pent-1-enyl]-5-oxo-cyclopentyl]sulphanylpropylsulphanyl] acetic acid (ONO-AE1-329), a selective EP4-receptor agonist. ONO-AE1-329 also enhanced dexamethasone-induced activation of a glucocorticoid response element reporter in BEAS-2B cells, which was similarly potentiated by RNO. In each airway epithelial cell variant, numerous genes that may impart therapeutic benefit in asthma, COPD, and/or IPF were differentially expressed by ONO-AE1-329, and those changes were often augmented by RNO and/or dexamethasone. We submit that an EP4-receptor agonist, either alone or as a combination therapy, may be beneficial in individuals with chronic lung diseases in whom current treatment options are inadequate. SIGNIFICANCE STATEMENT: Using human bronchial epithelial cells as a therapeutically relevant drug target, we report that EP4-receptor activation promoted gene expression changes that could provide therapeutic benefit in individuals with asthma, COPD, and IPF in whom current treatment options are ineffective or suboptimal.
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Affiliation(s)
- Radhika Joshi
- Department of Physiology and Pharmacology, Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Omar Hamed
- Department of Physiology and Pharmacology, Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Dong Yan
- Department of Physiology and Pharmacology, Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Aubrey N Michi
- Department of Physiology and Pharmacology, Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Mahmoud M Mostafa
- Department of Physiology and Pharmacology, Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Shahina Wiehler
- Department of Physiology and Pharmacology, Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Robert Newton
- Department of Physiology and Pharmacology, Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Mark A Giembycz
- Department of Physiology and Pharmacology, Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
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7
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Joshi R, Yan D, Hamed O, Giembycz MA. Transcriptomic Analysis Reveals Different Sensitivities of Genes to EP
4
Receptor Agonist Stimulation in BEAS‐2B Human Bronchial Epithelial Cells. FASEB J 2020. [DOI: 10.1096/fasebj.2020.34.s1.03638] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
| | - Dong Yan
- Pfizer Research Technology Center
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8
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Curtis MJ, Alexander S, Cirino G, Docherty JR, George CH, Giembycz MA, Hoyer D, Insel PA, Izzo AA, Ji Y, MacEwan DJ, Sobey CG, Stanford SC, Teixeira MM, Wonnacott S, Ahluwalia A. Experimental design and analysis and their reporting II: updated and simplified guidance for authors and peer reviewers. Br J Pharmacol 2019. [PMID: 29520785 DOI: 10.1111/bph.14153] [Citation(s) in RCA: 1078] [Impact Index Per Article: 215.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
This article updates the guidance published in 2015 for authors submitting papers to British Journal of Pharmacology (Curtis et al., 2015) and is intended to provide the rubric for peer review. Thus, it is directed towards authors, reviewers and editors. Explanations for many of the requirements were outlined previously and are not restated here. The new guidelines are intended to replace those published previously. The guidelines have been simplified for ease of understanding by authors, to make it more straightforward for peer reviewers to check compliance and to facilitate the curation of the journal's efforts to improve standards.
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Affiliation(s)
| | | | | | | | | | | | - Daniel Hoyer
- The University of Melbourne, Melbourne, VIC, Australia.,The Scripps Research Institute, San Diego, CA, USA
| | | | | | - Yong Ji
- Nanjing Medical University, Nanjing, China
| | | | | | | | - Mauro M Teixeira
- Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
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Joshi R, Yan D, Hamed O, Mostafa MM, Joshi T, Newton R, Giembycz MA. Impact of Phosphodiesterase 4 Inhibition on the Operational Efficacy, Response Maxima, and Kinetics of Indacaterol-Induced Gene Expression Changes in BEAS-2B Airway Epithelial Cells: A Global Transcriptomic Analysis. Mol Pharmacol 2019; 96:56-72. [DOI: 10.1124/mol.118.115311] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2018] [Accepted: 04/25/2019] [Indexed: 12/26/2022] Open
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10
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Joshi R, Yan D, Hamed O, Giembycz MA. The Effect of Phosphodiesterase 4 Inhibition on Gene Expression Changes Produced by Long Acting β
2
‐adrenoceptor Agonists in BEAS‐2B Airway Epithelial Cells. FASEB J 2019. [DOI: 10.1096/fasebj.2019.33.1_supplement.809.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Radhika Joshi
- Department of Physiology and PharmacologyUniversity of CalgaryCalgaryABCanada
| | - Dong Yan
- Department of Physiology and PharmacologyUniversity of CalgaryCalgaryABCanada
| | - Omar Hamed
- Department of Physiology and PharmacologyUniversity of CalgaryCalgaryABCanada
| | - Mark A Giembycz
- Department of Physiology and PharmacologyUniversity of CalgaryCalgaryABCanada
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11
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George T, Chakraborty M, Giembycz MA, Newton R. A bronchoprotective role for Rgs2 in a murine model of lipopolysaccharide-induced airways inflammation. Allergy Asthma Clin Immunol 2018; 14:40. [PMID: 30305828 PMCID: PMC6166284 DOI: 10.1186/s13223-018-0266-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Accepted: 05/22/2018] [Indexed: 02/07/2023] Open
Abstract
Background Asthma exacerbations are associated with the recruitment of neutrophils to the lungs. These cells release proteases and mediators, many of which act at G protein-coupled receptors (GPCRs) that couple via Gq to promote bronchoconstriction and inflammation. Common asthma therapeutics up-regulate expression of the regulator of G protein signalling (RGS), RGS2. As RGS2 reduces signaling from Gq-coupled GPCRs, we have defined role(s) for this GTPase-activating protein in an acute neutrophilic model of lung inflammation. Methods Wild type and Rgs2−/− C57Bl6 mice were exposed to nebulized lipopolysaccharide (LPS). Lung function (respiratory system resistance and compliance) was measured using a SCIREQ flexivent small animal ventilator. Lung inflammation was assessed by histochemistry, cell counting and by cytokine and chemokine expression in bronchoalveolar lavage (BAL) fluid. Results Lipopolysaccharide inhalation induced transient airways hyperreactivity (AHR) and neutrophilic lung inflammation. While AHR and inflammation was greatest 3 h post-LPS exposure, BAL neutrophils persisted for 24 h. At 3 h post-LPS inhalation, multiple inflammatory cytokines (CSF2, CSF3, IL6, TNF) and chemokines (CCL3, CCL4, CXCL1, CXCL2) were highly expressed in the BAL fluid, prior to declining by 24 h. Compared to wild type counterparts, Rgs2−/− mice developed significantly greater airflow resistance in response to inhaled methacholine (MCh) at 3 h post-LPS exposure. At 24 h post-LPS exposure, when lung function was recovering in the wild type animals, MCh-induced resistance was increased, and compliance decreased, in Rgs2−/− mice. Thus, Rgs2−/− mice show AHR and stiffer lungs 24 h post-LPS exposure. Histological markers of inflammation, total and differential cell counts, and major cytokine and chemokine expression in BAL fluid were similar between wild type and Rgs2−/− mice. However, 3 and 24 h post-LPS exposure, IL12B expression was significantly elevated in BAL fluid from Rgs2−/− mice compared to wild type animals. Conclusions While Rgs2 is bronchoprotective in acute neutrophilic inflammation, no clear anti-inflammatory effect was apparent. Nevertheless, elevated IL12B expression in Rgs2−/− animals raises the possibility that RGS2 could dampen Th1 responses. These findings indicate that up-regulation of RGS2, as occurs in response to inhaled corticosteroids and long-acting β2-adrenoceptor agonists, may be beneficial in acute neutrophilic exacerbations of airway disease, including asthma. Electronic supplementary material The online version of this article (10.1186/s13223-018-0266-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Tresa George
- 1Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, AB T2N 4Z6 Canada
| | - Mainak Chakraborty
- 2Immunology Research Group, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, AB T2N 4Z6 Canada
| | - Mark A Giembycz
- 1Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, AB T2N 4Z6 Canada
| | - Robert Newton
- 1Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, AB T2N 4Z6 Canada
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12
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Alexander SPH, Roberts RE, Broughton BRS, Sobey CG, George CH, Stanford SC, Cirino G, Docherty JR, Giembycz MA, Hoyer D, Insel PA, Izzo AA, Ji Y, MacEwan DJ, Mangum J, Wonnacott S, Ahluwalia A. Goals and practicalities of immunoblotting and immunohistochemistry: A guide for submission to the British Journal of Pharmacology. Br J Pharmacol 2018; 175:407-411. [PMID: 29350411 DOI: 10.1111/bph.14112] [Citation(s) in RCA: 518] [Impact Index Per Article: 86.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | - Yong Ji
- British Journal of Pharmacology, London, UK
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13
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Rider CF, Altonsy MO, Mostafa MM, Shah SV, Sasse S, Manson ML, Yan D, Kärrman-Mårdh C, Miller-Larsson A, Gerber AN, Giembycz MA, Newton R. Long-Acting β2-Adrenoceptor Agonists Enhance Glucocorticoid Receptor (GR)-Mediated Transcription by Gene-Specific Mechanisms Rather Than Generic Effects via GR. Mol Pharmacol 2018; 94:1031-1046. [PMID: 29959223 DOI: 10.1124/mol.118.112755] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2018] [Accepted: 06/25/2018] [Indexed: 12/16/2022] Open
Abstract
In asthma, the clinical efficacy of inhaled corticosteroids (ICSs) is enhanced by long-acting β2-adrenoceptor agonists (LABAs). ICSs, or more accurately, glucocorticoids, promote therapeutically relevant changes in gene expression, and, in primary human bronchial epithelial cells (pHBECs) and airway smooth muscle cells, this genomic effect can be enhanced by a LABA. Modeling this interaction in human bronchial airway epithelial BEAS-2B cells transfected with a 2× glucocorticoid response element (2×GRE)-driven luciferase reporter showed glucocorticoid-induced transcription to be enhanced 2- to 3-fold by LABA. This glucocorticoid receptor (GR; NR3C1)-dependent effect occurred rapidly, was insensitive to protein synthesis inhibition, and was maximal when glucocorticoid and LABA were added concurrently. The ability of LABA to enhance GR-mediated transcription was not associated with changes in GR expression, serine (Ser203, Ser211, Ser226) phosphorylation, ligand affinity, or nuclear translocation. Chromatin immunoprecipitation demonstrated that glucocorticoid-induced recruitment of GR to the integrated 2×GRE reporter and multiple gene loci, whose mRNAs were unaffected or enhanced by LABA, was also unchanged by LABA. Transcriptomic analysis revealed glucocorticoid-induced mRNAs were variably enhanced, unaffected, or repressed by LABA. Thus, events leading to GR binding at target genes are not the primary explanation for how LABAs modulate GR-mediated transcription. As many glucocorticoid-induced genes are independently induced by LABA, gene-specific control by GR- and LABA-activated transcription factors may explain these observations. Because LABAs promote similar effects in pHBECs, therapeutic relevance is likely. These data illustrate the need to understand gene function(s), and the mechanisms leading to gene-specific induction, if existing ICS/LABA combination therapies are to be improved.
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Affiliation(s)
- Christopher F Rider
- Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada (C.F.R., M.O.A., M.M.M., S.V.S., D.Y., M.A.G., R.N.); Department of Zoology, Sohag University, Sohag, Egypt (M.O.A.); Department of Medicine, National Jewish Health, Denver, Colorado (S.S., A.N.G.); and Bioscience, Respiratory, Inflammation, and Autoimmunity, IMED Biotech Unit (M.L.M., C.K.-M.), and Respiratory GMed (A.M.-L.), AstraZeneca, Gothenburg, Molndal, Sweden
| | - Mohammed O Altonsy
- Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada (C.F.R., M.O.A., M.M.M., S.V.S., D.Y., M.A.G., R.N.); Department of Zoology, Sohag University, Sohag, Egypt (M.O.A.); Department of Medicine, National Jewish Health, Denver, Colorado (S.S., A.N.G.); and Bioscience, Respiratory, Inflammation, and Autoimmunity, IMED Biotech Unit (M.L.M., C.K.-M.), and Respiratory GMed (A.M.-L.), AstraZeneca, Gothenburg, Molndal, Sweden
| | - Mahmoud M Mostafa
- Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada (C.F.R., M.O.A., M.M.M., S.V.S., D.Y., M.A.G., R.N.); Department of Zoology, Sohag University, Sohag, Egypt (M.O.A.); Department of Medicine, National Jewish Health, Denver, Colorado (S.S., A.N.G.); and Bioscience, Respiratory, Inflammation, and Autoimmunity, IMED Biotech Unit (M.L.M., C.K.-M.), and Respiratory GMed (A.M.-L.), AstraZeneca, Gothenburg, Molndal, Sweden
| | - Suharsh V Shah
- Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada (C.F.R., M.O.A., M.M.M., S.V.S., D.Y., M.A.G., R.N.); Department of Zoology, Sohag University, Sohag, Egypt (M.O.A.); Department of Medicine, National Jewish Health, Denver, Colorado (S.S., A.N.G.); and Bioscience, Respiratory, Inflammation, and Autoimmunity, IMED Biotech Unit (M.L.M., C.K.-M.), and Respiratory GMed (A.M.-L.), AstraZeneca, Gothenburg, Molndal, Sweden
| | - Sarah Sasse
- Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada (C.F.R., M.O.A., M.M.M., S.V.S., D.Y., M.A.G., R.N.); Department of Zoology, Sohag University, Sohag, Egypt (M.O.A.); Department of Medicine, National Jewish Health, Denver, Colorado (S.S., A.N.G.); and Bioscience, Respiratory, Inflammation, and Autoimmunity, IMED Biotech Unit (M.L.M., C.K.-M.), and Respiratory GMed (A.M.-L.), AstraZeneca, Gothenburg, Molndal, Sweden
| | - Martijn L Manson
- Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada (C.F.R., M.O.A., M.M.M., S.V.S., D.Y., M.A.G., R.N.); Department of Zoology, Sohag University, Sohag, Egypt (M.O.A.); Department of Medicine, National Jewish Health, Denver, Colorado (S.S., A.N.G.); and Bioscience, Respiratory, Inflammation, and Autoimmunity, IMED Biotech Unit (M.L.M., C.K.-M.), and Respiratory GMed (A.M.-L.), AstraZeneca, Gothenburg, Molndal, Sweden
| | - Dong Yan
- Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada (C.F.R., M.O.A., M.M.M., S.V.S., D.Y., M.A.G., R.N.); Department of Zoology, Sohag University, Sohag, Egypt (M.O.A.); Department of Medicine, National Jewish Health, Denver, Colorado (S.S., A.N.G.); and Bioscience, Respiratory, Inflammation, and Autoimmunity, IMED Biotech Unit (M.L.M., C.K.-M.), and Respiratory GMed (A.M.-L.), AstraZeneca, Gothenburg, Molndal, Sweden
| | - Carina Kärrman-Mårdh
- Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada (C.F.R., M.O.A., M.M.M., S.V.S., D.Y., M.A.G., R.N.); Department of Zoology, Sohag University, Sohag, Egypt (M.O.A.); Department of Medicine, National Jewish Health, Denver, Colorado (S.S., A.N.G.); and Bioscience, Respiratory, Inflammation, and Autoimmunity, IMED Biotech Unit (M.L.M., C.K.-M.), and Respiratory GMed (A.M.-L.), AstraZeneca, Gothenburg, Molndal, Sweden
| | - Anna Miller-Larsson
- Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada (C.F.R., M.O.A., M.M.M., S.V.S., D.Y., M.A.G., R.N.); Department of Zoology, Sohag University, Sohag, Egypt (M.O.A.); Department of Medicine, National Jewish Health, Denver, Colorado (S.S., A.N.G.); and Bioscience, Respiratory, Inflammation, and Autoimmunity, IMED Biotech Unit (M.L.M., C.K.-M.), and Respiratory GMed (A.M.-L.), AstraZeneca, Gothenburg, Molndal, Sweden
| | - Anthony N Gerber
- Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada (C.F.R., M.O.A., M.M.M., S.V.S., D.Y., M.A.G., R.N.); Department of Zoology, Sohag University, Sohag, Egypt (M.O.A.); Department of Medicine, National Jewish Health, Denver, Colorado (S.S., A.N.G.); and Bioscience, Respiratory, Inflammation, and Autoimmunity, IMED Biotech Unit (M.L.M., C.K.-M.), and Respiratory GMed (A.M.-L.), AstraZeneca, Gothenburg, Molndal, Sweden
| | - Mark A Giembycz
- Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada (C.F.R., M.O.A., M.M.M., S.V.S., D.Y., M.A.G., R.N.); Department of Zoology, Sohag University, Sohag, Egypt (M.O.A.); Department of Medicine, National Jewish Health, Denver, Colorado (S.S., A.N.G.); and Bioscience, Respiratory, Inflammation, and Autoimmunity, IMED Biotech Unit (M.L.M., C.K.-M.), and Respiratory GMed (A.M.-L.), AstraZeneca, Gothenburg, Molndal, Sweden
| | - Robert Newton
- Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada (C.F.R., M.O.A., M.M.M., S.V.S., D.Y., M.A.G., R.N.); Department of Zoology, Sohag University, Sohag, Egypt (M.O.A.); Department of Medicine, National Jewish Health, Denver, Colorado (S.S., A.N.G.); and Bioscience, Respiratory, Inflammation, and Autoimmunity, IMED Biotech Unit (M.L.M., C.K.-M.), and Respiratory GMed (A.M.-L.), AstraZeneca, Gothenburg, Molndal, Sweden
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Yan D, Hamed O, Joshi T, Mostafa MM, Jamieson KC, Joshi R, Newton R, Giembycz MA. Analysis of the Indacaterol-Regulated Transcriptome in Human Airway Epithelial Cells Implicates Gene Expression Changes in the Adverse and Therapeutic Effects of β2-Adrenoceptor Agonists. J Pharmacol Exp Ther 2018; 366:220-236. [PMID: 29653961 DOI: 10.1124/jpet.118.249292] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2018] [Accepted: 04/11/2018] [Indexed: 12/13/2022] Open
Abstract
The contribution of gene expression changes to the adverse and therapeutic effects of β2-adrenoceptor agonists in asthma was investigated using human airway epithelial cells as a therapeutically relevant target. Operational model-fitting established that the long-acting β2-adrenoceptor agonists (LABA) indacaterol, salmeterol, formoterol, and picumeterol were full agonists on BEAS-2B cells transfected with a cAMP-response element reporter but differed in efficacy (indacaterol ≥ formoterol > salmeterol ≥ picumeterol). The transcriptomic signature of indacaterol in BEAS-2B cells identified 180, 368, 252, and 10 genes that were differentially expressed (>1.5- to <0.67-fold) after 1-, 2-, 6-, and 18-hour of exposure, respectively. Many upregulated genes (e.g., AREG, BDNF, CCL20, CXCL2, EDN1, IL6, IL15, IL20) encode proteins with proinflammatory activity and are annotated by several, enriched gene ontology (GO) terms, including cellular response to interleukin-1, cytokine activity, and positive regulation of neutrophil chemotaxis The general enriched GO term extracellular space was also associated with indacaterol-induced genes, and many of those, including CRISPLD2, DMBT1, GAS1, and SOCS3, have putative anti-inflammatory, antibacterial, and/or antiviral activity. Numerous indacaterol-regulated genes were also induced or repressed in BEAS-2B cells and human primary bronchial epithelial cells by the low efficacy LABA salmeterol, indicating that this genomic effect was neither unique to indacaterol nor restricted to the BEAS-2B airway epithelial cell line. Collectively, these data suggest that the consequences of inhaling a β2-adrenoceptor agonist may be complex and involve widespread changes in gene expression. We propose that this genomic effect represents a generally unappreciated mechanism that may contribute to the adverse and therapeutic actions of β2-adrenoceptor agonists in asthma.
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Affiliation(s)
- Dong Yan
- Departments of Physiology and Pharmacology (D.Y., O.H., T.J., K.C.J., R.J., M.A.G.) and Cell Biology and Anatomy (M.M.M., R.N.), Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Omar Hamed
- Departments of Physiology and Pharmacology (D.Y., O.H., T.J., K.C.J., R.J., M.A.G.) and Cell Biology and Anatomy (M.M.M., R.N.), Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Taruna Joshi
- Departments of Physiology and Pharmacology (D.Y., O.H., T.J., K.C.J., R.J., M.A.G.) and Cell Biology and Anatomy (M.M.M., R.N.), Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Mahmoud M Mostafa
- Departments of Physiology and Pharmacology (D.Y., O.H., T.J., K.C.J., R.J., M.A.G.) and Cell Biology and Anatomy (M.M.M., R.N.), Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Kyla C Jamieson
- Departments of Physiology and Pharmacology (D.Y., O.H., T.J., K.C.J., R.J., M.A.G.) and Cell Biology and Anatomy (M.M.M., R.N.), Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Radhika Joshi
- Departments of Physiology and Pharmacology (D.Y., O.H., T.J., K.C.J., R.J., M.A.G.) and Cell Biology and Anatomy (M.M.M., R.N.), Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Robert Newton
- Departments of Physiology and Pharmacology (D.Y., O.H., T.J., K.C.J., R.J., M.A.G.) and Cell Biology and Anatomy (M.M.M., R.N.), Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Mark A Giembycz
- Departments of Physiology and Pharmacology (D.Y., O.H., T.J., K.C.J., R.J., M.A.G.) and Cell Biology and Anatomy (M.M.M., R.N.), Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
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15
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Huff RD, Rider CF, Yan D, Newton R, Giembycz MA, Carlsten C, Hirota JA. Inhibition of ABCC4 potentiates combination beta agonist and glucocorticoid responses in human airway epithelial cells. J Allergy Clin Immunol 2017; 141:1127-1130.e5. [PMID: 29103996 DOI: 10.1016/j.jaci.2017.10.011] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Revised: 09/27/2017] [Accepted: 10/04/2017] [Indexed: 10/18/2022]
Affiliation(s)
- Ryan D Huff
- Division of Respiratory Medicine, Department of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Christopher F Rider
- Division of Respiratory Medicine, Department of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Dong Yan
- Department of Physiology & Pharmacology, Snyder Institute of Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Robert Newton
- Department of Cell Biology & Anatomy, Snyder Institute of Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Mark A Giembycz
- Department of Physiology & Pharmacology, Snyder Institute of Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Chris Carlsten
- Division of Respiratory Medicine, Department of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Jeremy A Hirota
- Firestone Institute for Respiratory Health, Division of Respirology, Department of Medicine, McMaster University, Hamilton, Ontario, Canada.
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16
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George CH, Stanford SC, Alexander S, Cirino G, Docherty JR, Giembycz MA, Hoyer D, Insel PA, Izzo AA, Ji Y, MacEwan DJ, Sobey CG, Wonnacott S, Ahluwalia A. Updating the guidelines for data transparency in the British Journal of Pharmacology - data sharing and the use of scatter plots instead of bar charts. Br J Pharmacol 2017; 174:2801-2804. [PMID: 28801996 PMCID: PMC5554317 DOI: 10.1111/bph.13925] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Affiliation(s)
| | | | | | | | | | | | | | | | | | - Yong Ji
- British Journal of PharmacologyLondonUK
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17
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George T, Bell M, Chakraborty M, Siderovski DP, Giembycz MA, Newton R. Protective Roles for RGS2 in a Mouse Model of House Dust Mite-Induced Airway Inflammation. PLoS One 2017; 12:e0170269. [PMID: 28107494 PMCID: PMC5249169 DOI: 10.1371/journal.pone.0170269] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Accepted: 12/30/2016] [Indexed: 12/16/2022] Open
Abstract
The GTPase-accelerating protein, regulator of G-protein signalling 2 (RGS2) reduces signalling from G-protein-coupled receptors (GPCRs) that signal via Gαq. In humans, RGS2 expression is up-regulated by inhaled corticosteroids (ICSs) and long-acting β2-adrenoceptor agonists (LABAs) such that synergy is produced in combination. This may contribute to the superior clinical efficacy of ICS/LABA therapy in asthma relative to ICS alone. In a murine model of house dust mite (HDM)-induced airways inflammation, three weeks of intranasal HDM (25 μg, 3×/week) reduced lung function and induced granulocytic airways inflammation. Compared to wild type animals, Rgs2-/- mice showed airways hyperresponsiveness (increased airways resistance and reduced compliance). While HDM increased pulmonary inflammation observed on hematoxylin and eosin-stained sections, there was no difference between wild type and Rgs2-/- animals. HDM-induced mucus hypersecretion was also unaffected by RGS2 deficiency. However, inflammatory cell counts in the bronchoalveolar lavage fluid of Rgs2-/- animals were significantly increased (57%) compared to wild type animals and this correlated with increased granulocyte (neutrophil and eosinophil) numbers. Likewise, cytokine and chemokine (IL4, IL17, IL5, LIF, IL6, CSF3, CXCLl, CXCL10 and CXCL11) release was increased by HDM exposure. Compared to wild type, Rgs2-/- animals showed a trend towards increased expression for many cytokines/chemokines, with CCL3, CCL11, CXCL9 and CXCL10 being significantly enhanced. As RGS2 expression was unaffected by HDM exposure, these data indicate that RGS2 exerts tonic bronchoprotection in HDM-induced airways inflammation. Modest anti-inflammatory and anti-remodelling roles for RGS2 are also suggested. If translatable to humans, therapies that maximize RGS2 expression may prove advantageous.
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Affiliation(s)
- Tresa George
- Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada
| | - Matthew Bell
- Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada
| | - Mainak Chakraborty
- Immunology Research Group, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada
| | - David P. Siderovski
- Blanchette Rockefeller Neuroscience Institute, West Virginia University, Morgantown, West Virginia, United States of America
| | - Mark A. Giembycz
- Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada
| | - Robert Newton
- Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada
- * E-mail:
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18
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Joshi T, Yan D, Hamed O, Tannheimer SL, Phillips GB, Wright CD, Kim M, Salmon M, Newton R, Giembycz MA. GS-5759, a Bifunctional β2-Adrenoceptor Agonist and Phosphodiesterase 4 Inhibitor for Chronic Obstructive Pulmonary Disease with a Unique Mode of Action: Effects on Gene Expression in Human Airway Epithelial Cells. J Pharmacol Exp Ther 2016; 360:324-340. [DOI: 10.1124/jpet.116.237743] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2016] [Accepted: 12/05/2016] [Indexed: 12/31/2022] Open
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Newton R, Giembycz MA. Understanding how long-acting β 2 -adrenoceptor agonists enhance the clinical efficacy of inhaled corticosteroids in asthma - an update. Br J Pharmacol 2016; 173:3405-3430. [PMID: 27646470 DOI: 10.1111/bph.13628] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Revised: 08/19/2016] [Accepted: 08/21/2016] [Indexed: 12/18/2022] Open
Abstract
In moderate-to-severe asthma, adding an inhaled long-acting β2 -adenoceptor agonist (LABA) to an inhaled corticosteroid (ICS) provides better disease control than simply increasing the dose of ICS. Acting on the glucocorticoid receptor (GR, gene NR3C1), ICSs promote anti-inflammatory/anti-asthma gene expression. In vitro, LABAs synergistically enhance the maximal expression of many glucocorticoid-induced genes. Other genes, including dual-specificity phosphatase 1(DUSP1) in human airways smooth muscle (ASM) and epithelial cells, are up-regulated additively by both drug classes. Synergy may also occur for LABA-induced genes, as illustrated by the bronchoprotective gene, regulator of G-protein signalling 2 (RGS2) in ASM. Such effects cannot be produced by either drug alone and may explain the therapeutic efficacy of ICS/LABA combination therapies. While the molecular basis of synergy remains unclear, mechanistic interpretations must accommodate gene-specific regulation. We explore the concept that each glucocorticoid-induced gene is an independent signal transducer optimally activated by a specific, ligand-directed, GR conformation. In addition to explaining partial agonism, this realization provides opportunities to identify novel GR ligands that exhibit gene expression bias. Translating this into improved therapeutic ratios requires consideration of GR density in target tissues and further understanding of gene function. Similarly, the ability of a LABA to interact with a glucocorticoid may be suboptimal due to low β2 -adrenoceptor density or biased β2 -adrenoceptor signalling. Strategies to overcome these limitations include adding-on a phosphodiesterase inhibitor and using agonists of other Gs-coupled receptors. In all cases, the rational design of ICS/LABA, and derivative, combination therapies requires functional knowledge of induced (and repressed) genes for therapeutic benefit to be maximized.
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Affiliation(s)
- Robert Newton
- Department of Cell Biology and Anatomy, Airways Inflammation Research Group, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Mark A Giembycz
- Department of Physiology and Pharmacology, Airways Inflammation Research Group, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
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20
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Fernando MR, Giembycz MA, McKay DM. Bidirectional crosstalk via IL-6, PGE2 and PGD2 between murine myofibroblasts and alternatively activated macrophages enhances anti-inflammatory phenotype in both cells. Br J Pharmacol 2016; 173:899-912. [PMID: 26676587 DOI: 10.1111/bph.13409] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Revised: 11/25/2015] [Accepted: 12/10/2015] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND AND PURPOSE Alternatively activated macrophages (AAMs) are important cells in the resolution of inflammation and tissue repair. We examined the impact of myofibroblasts, a vital cell in wound healing and tissue repair, on the development and function of AAMs. EXPERIMENTAL APPROACH The interaction between AAMs and myofibroblasts was tested using conditioned medium from murine dermal myofibroblasts and bone marrow-derived macrophages. AAMs were differentiated with IL-4 and IL-13. KEY RESULTS Conditioned medium from myofibroblasts enhanced the expression of AAM markers, arginase 1 and Ym1 (chitinase-3-like 3) and the spontaneous production of IL-10, while suppressing LPS-induced nitric oxide production. IL-6 from the myofibroblasts contributed to the amplification of the AAM phenotype; the selective COX-2 inhibitor, NS-398, significantly reduced the ability of myofibroblasts to promote an AAM phenotype. Pharmacological analyses indicated that myofibroblast-derived IL-6 enhanced arginase activity and spontaneous IL-10 output, while PGE2 , via the EP4 receptor, enhanced arginase expression and LPS-evoked IL-10 production. PGD2 suppressed LPS-evoked nitric oxide via the DP1 receptor. Reciprocally, conditioned medium from macrophages treated with IL-4 + IL-13 and myofibroblast conditioned medium components, but not macrophages given IL-4 + IL-13 only, reduced myofibroblast migration, the expression of COX-2, and the production of PGE2 and PGD2 . CONCLUSIONS AND IMPLICATIONS These findings define mechanisms by which myofibroblasts enhance an AAM phenotype, which can promote wound healing directly, and/or via feedback communication to the myofibroblast, subsequently down-regulating its capacity to promote AAM function. This is an important homeostatic regulatory pathway in wound healing that can also limit unwanted fibrosis.
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Affiliation(s)
- Maria R Fernando
- Gastrointestinal Research Group and Inflammation Research Network
| | - Mark A Giembycz
- Airways Inflammation Research Group, Department of Physiology & Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Derek M McKay
- Gastrointestinal Research Group and Inflammation Research Network
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21
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Curtis MJ, Bond RA, Spina D, Ahluwalia A, Alexander SPA, Giembycz MA, Gilchrist A, Hoyer D, Insel PA, Izzo AA, Lawrence AJ, MacEwan DJ, Moon LDF, Wonnacott S, Weston AH, McGrath JC. Experimental design and analysis and their reporting: new guidance for publication in BJP. Br J Pharmacol 2015; 172:3461-71. [PMID: 26114403 PMCID: PMC4507152 DOI: 10.1111/bph.12856] [Citation(s) in RCA: 924] [Impact Index Per Article: 102.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Linked EditorialsThis Editorial is part of a series. To view the other Editorials in this series, visit: http://onlinelibrary.wiley.com/doi/10.1111/bph.12956/abstract; http://onlinelibrary.wiley.com/doi/10.1111/bph.12954/abstract; http://onlinelibrary.wiley.com/doi/10.1111/bph.12955/abstract and http://onlinelibrary.wiley.com/doi/10.1111/bph.13112/abstract
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Affiliation(s)
| | | | | | | | | | | | | | - Daniel Hoyer
- Editorial Office, British Journal of Pharmacology
| | - Paul A Insel
- Editorial Office, British Journal of Pharmacology
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Joshi T, Johnson M, Newton R, Giembycz MA. The long-acting β2 -adrenoceptor agonist, indacaterol, enhances glucocorticoid receptor-mediated transcription in human airway epithelial cells in a gene- and agonist-dependent manner. Br J Pharmacol 2015; 172:2634-53. [PMID: 25598440 DOI: 10.1111/bph.13087] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2014] [Revised: 12/11/2014] [Accepted: 01/13/2015] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND AND PURPOSE Inhaled glucocorticoid (ICS)/long-acting β2 -adrenoceptor agonist (LABA) combination therapy is a recommended treatment option for patients with moderate/severe asthma in whom adequate control cannot be achieved by an ICS alone. Previously, we discovered that LABAs can augment dexamethasone-inducible gene expression and proposed that this effect may explain how these two drugs interact to deliver superior clinical benefit. Herein, we extended that observation by analysing, pharmacodynamically, the effect of the LABA, indacaterol, on glucocorticoid receptor (GR)-mediated gene transcription induced by seven ligands with intrinsic activity values that span the spectrum of full agonism to antagonism. EXPERIMENTAL APPROACH BEAS-2B human airway epithelial cells stably transfected with a 2× glucocorticoid response element luciferase reporter were used to model gene transcription together with an analysis of several glucocorticoid-inducible genes. KEY RESULTS Indacaterol augmented glucocorticoid-induced reporter activation in a manner that was positively related to the intrinsic activity of the GR agonist. This effect was demonstrated by an increase in response maxima without a change in GR agonist affinity or efficacy. Indacaterol also enhanced glucocorticoid-inducible gene expression. However, the magnitude of this effect was dependent on both the GR agonist and the gene of interest. CONCLUSIONS AND IMPLICATIONS These data suggest that indacaterol activates a molecular rheostat, which increases the transcriptional competency of GR in an agonist- and gene-dependent manner without apparently changing the relationship between fractional GR occupancy and response. These findings provide a platform to rationally design ICS/LABA combination therapy that is based on the generation of agonist-dependent gene expression profiles in target and off-target tissues.
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Affiliation(s)
- T Joshi
- Department of Physiology and Pharmacology, University of Calgary, Calgary, Alberta, Canada
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Giembycz MA, Newton R. Potential mechanisms to explain how LABAs and PDE4 inhibitors enhance the clinical efficacy of glucocorticoids in inflammatory lung diseases. F1000Prime Rep 2015; 7:16. [PMID: 25750734 PMCID: PMC4335793 DOI: 10.12703/p7-16] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Inhaled glucocorticoids acting via the glucocorticoid receptor are a mainstay treatment option for individuals with asthma. There is a consensus that the remedial actions of inhaled glucocorticoids are due to their ability to suppress inflammation by modulating gene expression. While inhaled glucocorticoids are generally effective in asthma, there are subjects with moderate-to-severe disease in whom inhaled glucocorticoids fail to provide adequate control. For these individuals, asthma guidelines recommend that a long-acting β2-adrenoceptor agonist (LABA) be administered concurrently with an inhaled glucocorticoid. This so-called “combination therapy” is often effective and clinically superior to the inhaled glucocorticoid alone, irrespective of dose. LABAs, and another class of drug known as phosphodiesterase 4 (PDE4) inhibitors, may also enhance the efficacy of inhaled glucocorticoids in chronic obstructive pulmonary disease (COPD). In both conditions, these drugs are believed to work by elevating the concentration of cyclic adenosine-3',5'-monophosphate (cAMP) in target cells and tissues. Despite the success of inhaled glucocorticoid/LABA combination therapy, it remains unclear how an increase in cAMP enhances the clinical efficacy of an inhaled glucocorticoid. In this report, we provide a state-of-the-art appraisal, including unresolved and controversial issues, of how cAMP-elevating drugs and inhaled glucocorticoids interact at a molecular level to deliver enhanced anti-inflammatory benefit over inhaled glucocorticoid monotherapy. We also speculate on ways to further exploit this desirable interaction. Critical discussion of how these two drug classes regulate gene transcription, often in a synergistic manner, is a particular focus. Indeed, because interplay between glucocorticoid receptor and cAMP signaling pathways may contribute to the superiority of inhaled glucocorticoid/LABA combination therapy, understanding this interaction may provide a logical framework to rationally design these multicomponent therapeutics that was not previously possible.
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Affiliation(s)
- Mark A. Giembycz
- Department of Physiology & Pharmacology, Snyder Institute of Chronic Diseases, Cumming School of Medicine, University of Calgary3820 Hospital Drive NW, Calgary, AlbertaCanada T2N 1N4
| | - Robert Newton
- Department of Cell Biology & Anatomy, Snyder Institute of Chronic Diseases, Cumming School of Medicine, University of Calgary3820 Hospital Drive NW, Calgary, AlbertaCanada T2N 1N4
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Rider CF, Shah S, Miller-Larsson A, Giembycz MA, Newton R. Cytokine-induced loss of glucocorticoid function: effect of kinase inhibitors, long-acting β(2)-adrenoceptor [corrected] agonist and glucocorticoid receptor ligands. PLoS One 2015; 10:e0116773. [PMID: 25625944 PMCID: PMC4308083 DOI: 10.1371/journal.pone.0116773] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2014] [Accepted: 12/13/2014] [Indexed: 11/19/2022] Open
Abstract
Acting on the glucocorticoid receptor (NR3C1), glucocorticoids are widely used to treat inflammatory diseases. However, glucocorticoid resistance often leads to suboptimal asthma control. Since glucocorticoid-induced gene expression contributes to glucocorticoid activity, the aim of this study was to use a 2 × glucocorticoid response element (GRE) reporter and glucocorticoid-induced gene expression to investigate approaches to combat cytokine-induced glucocorticoid resistance. Pre-treatment with tumor necrosis factor-α (TNF) or interleukin-1β inhibited dexamethasone-induced mRNA expression of the putative anti-inflammatory genes RGS2 and TSC22D3, or just TSC22D3, in primary human airway epithelial and smooth muscle cells, respectively. Dexamethasone-induced DUSP1 mRNA was unaffected. In human bronchial epithelial BEAS-2B cells, dexamethasone-induced TSC22D3 and CDKN1C expression (at 6 h) was reduced by TNF pre-treatment, whereas DUSP1 and RGS2 mRNAs were unaffected. TNF pre-treatment also reduced dexamethasone-dependent 2×GRE reporter activation. This was partially reversed by PS-1145 and c-jun N-terminal kinase (JNK) inhibitor VIII, inhibitors of IKK2 and JNK, respectively. However, neither inhibitor affected TNF-dependent loss of dexamethasone-induced CDKN1C or TSC22D3 mRNA. Similarly, inhibitors of the extracellular signal-regulated kinase, p38, phosphoinositide 3-kinase or protein kinase C pathways failed to attenuate TNF-dependent repression of the 2×GRE reporter. Fluticasone furoate, fluticasone propionate and budesonide were full agonists relative to dexamethasone, while GSK9027, RU24858, des-ciclesonide and GW870086X were partial agonists on the 2×GRE reporter. TNF reduced reporter activity in proportion with agonist efficacy. Full and partial agonists showed various degrees of agonism on RGS2 and TSC22D3 expression, but were equally effective at inducing CDKN1C and DUSP1, and did not affect the repression of CDKN1C or TSC22D3 expression by TNF. Finally, formoterol-enhanced 2×GRE reporter activity was also proportional to agonist efficacy and functionally reversed repression by TNF. As similar effects were apparent on glucocorticoid-induced gene expression, the most effective strategy to overcome glucocorticoid resistance in this model was addition of formoterol to high efficacy NR3C1 agonists.
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Affiliation(s)
- Christopher F. Rider
- Airways Inflammation Research Group, Snyder Institute of Chronic Diseases, Faculty of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Suharsh Shah
- Airways Inflammation Research Group, Snyder Institute of Chronic Diseases, Faculty of Medicine, University of Calgary, Calgary, Alberta, Canada
| | | | - Mark A. Giembycz
- Airways Inflammation Research Group, Snyder Institute of Chronic Diseases, Faculty of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Robert Newton
- Airways Inflammation Research Group, Snyder Institute of Chronic Diseases, Faculty of Medicine, University of Calgary, Calgary, Alberta, Canada
- * E-mail:
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BinMahfouz H, Borthakur B, Yan D, George T, Giembycz MA, Newton R. Superiority of combined phosphodiesterase PDE3/PDE4 inhibition over PDE4 inhibition alone on glucocorticoid- and long-acting β2-adrenoceptor agonist-induced gene expression in human airway epithelial cells. Mol Pharmacol 2014; 87:64-76. [PMID: 25324049 DOI: 10.1124/mol.114.093393] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Glucocorticoids, also known as corticosteroids, induce effector gene transcription as a part of their anti-inflammatory mechanisms of action. Such genomic effects can be significantly enhanced by long-acting β2-adrenoceptor agonists (LABAs) and may contribute to the clinical superiority of inhaled corticosteroid (ICS)/LABA combinations in asthma and chronic obstructive pulmonary disease (COPD) over ICSs alone. Using models of cAMP- and glucocorticoid-induced transcription in human bronchial epithelial BEAS-2B cells, we show that combining inhibitors of phosphodiesterase (PDE) 3 and PDE4 provides greater benefits compared with inhibiting either PDE alone. In respect to cAMP-dependent transcription, inhibitors of PDE3 (siguazodan, cilostazol) and PDE4 (rolipram, GSK256066, roflumilast N-oxide) each sensitized to the LABA, formoterol. This effect was magnified by dual PDE3 and PDE4 inhibition. Siguazodan plus rolipram was also more effective at inducing cAMP-dependent transcription than either inhibitor alone. Conversely, the concentration-response curve describing the enhancement of dexamethasone-induced, glucocorticoid response element-dependent transcription by formoterol was displaced to the left by PDE4, but not PDE3, inhibition. Overall, similar effects were described for bona fide genes, including RGS2, CD200, and CRISPLD2. Importantly, the combination of siguazodan plus rolipram prolonged the duration of gene expression induced by formoterol, dexamethasone, or dexamethasone plus formoterol. This was most apparent for RGS2, a bronchoprotective gene that may also reduce the proinflammatory effects of constrictor mediators. Collectively, these data provide a rationale for the use of PDE3 and PDE4 inhibitors in the treatment of COPD and asthma where they may enhance, sensitize, and prolong the effects of LABA/ICS combination therapies.
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Affiliation(s)
- Hawazen BinMahfouz
- Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, Faculty of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Bibhusana Borthakur
- Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, Faculty of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Dong Yan
- Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, Faculty of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Tresa George
- Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, Faculty of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Mark A Giembycz
- Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, Faculty of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Robert Newton
- Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, Faculty of Medicine, University of Calgary, Calgary, Alberta, Canada
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Giembycz MA, Maurice DH. Cyclic nucleotide-based therapeutics for chronic obstructive pulmonary disease. Curr Opin Pharmacol 2014; 16:89-107. [PMID: 24810285 DOI: 10.1016/j.coph.2014.04.001] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2014] [Revised: 04/10/2014] [Accepted: 04/11/2014] [Indexed: 12/18/2022]
Abstract
Chronic obstructive pulmonary disease (COPD) defines a group of chronic inflammatory disorders of the airways that are characterised by a progressive and largely irreversible decline in expiratory airflow. Drugs used to treat COPD through actions mediated by cyclic AMP (cAMP) are restricted to long-acting and short-acting β2-adrenoceptor agonists and, in a subset of patients with chronic bronchitis, a phosphodiesterase 4 inhibitor, roflumilast. These agents relax airway smooth muscle and suppress inflammation. At the molecular level, these effects in the airways are mediated by two cAMP effectors, cAMP-dependent protein kinase and exchange proteins activated by cAMP. The pharmacology of newer agents, acting through these systems, is discussed here with an emphasis on their potential to interact and increase therapeutic effectiveness.
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Affiliation(s)
- Mark A Giembycz
- Department of Physiology & Pharmacology, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada
| | - Donald H Maurice
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada.
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Giembycz MA, Newton R. How Phosphodiesterase 4 Inhibitors Work in Patients with Chronic Obstructive Pulmonary Disease of the Severe, Bronchitic, Frequent Exacerbator Phenotype. Clin Chest Med 2014; 35:203-17. [DOI: 10.1016/j.ccm.2013.09.007] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Birrell MA, Maher SA, Buckley J, Dale N, Bonvini S, Raemdonck K, Pullen N, Giembycz MA, Belvisi MG. Selectivity profiling of the novel EP2 receptor antagonist, PF-04418948, in functional bioassay systems: atypical affinity at the guinea pig EP2 receptor. Br J Pharmacol 2014; 168:129-38. [PMID: 22747912 DOI: 10.1111/j.1476-5381.2012.02088.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND AND PURPOSE Understanding the role of the EP(2) receptor has been hampered by the lack of a selective antagonist. Recently, a selective EP(2) receptor antagonist, PF-04418948, has been discovered. The aim of this study was to demonstrate the selectivity profile of PF-04418948 for the EP(2) receptor over other EP receptors using a range of isolated tissue systems. EXPERIMENTAL APPROACH PF-04418948 was profiled on a range of isolated tissues to assess its EP receptor potency and selectivity: ONO-DI-004-induced contraction of guinea pig trachea (EP(1)); ONO-AE1-259 and PGE(2)- induced relaxation of mouse and guinea pig trachea (EP(2)); PGE(2)-induced depolarization of guinea pig isolated vagus (EP(3)); PGE(2)-induced relaxation of human and rat trachea (EP(4)). PF-04418948 was also profiled in functional murine TP, IP, DP and FP receptor assays. KEY RESULTS In bioassay systems, where assessment of potency/selectivity is made against the 'native' receptor, PF-04418948 only acted as an antagonist of EP(2) receptor-mediated events. PF-04418948 competitively inhibited relaxations of murine and guinea pig trachea induced by ONO-AE1-259 and PGE(2) respectively. However, the affinity of PF-04418948 was not equal in the two preparations. CONCLUSIONS AND IMPLICATIONS Using a wide range of bioassay systems, we have demonstrated that PF-04418948 is a selective EP(2)-receptor antagonist. Interestingly, an atypically low affinity was found on the guinea pig trachea, questioning its utility as an EP(2) receptor assay system. Nevertheless, this compound should be an invaluable tool for investigating the biological activity of PGE(2) and the role of EP(2) receptors in health and disease.
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Affiliation(s)
- Mark A Birrell
- Respiratory Pharmacology, Pharmacology & Toxicology Section, Imperial College London, Faculty of Medicine, National Heart and Lung Institute, UK.
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Holden NS, George T, Rider CF, Chandrasekhar A, Shah S, Kaur M, Johnson M, Siderovski DP, Leigh R, Giembycz MA, Newton R. Induction of regulator of G-protein signaling 2 expression by long-acting β2-adrenoceptor agonists and glucocorticoids in human airway epithelial cells. J Pharmacol Exp Ther 2013; 348:12-24. [PMID: 24163441 DOI: 10.1124/jpet.113.204586] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
In asthma and chronic obstructive pulmonary disease (COPD) multiple mediators act on Gαq-linked G-protein-coupled receptors (GPCRs) to cause bronchoconstriction. However, acting on the airway epithelium, such mediators may also elicit inflammatory responses. In human bronchial epithelial BEAS-2B cells (bronchial epithelium + adenovirus 12-SV40 hybrid), regulator of G-protein signaling (RGS) 2 mRNA and protein were synergistically induced in response to combinations of long-acting β2-adrenoceptor agonist (LABA) (salmeterol, formoterol) plus glucocorticoid (dexamethasone, fluticasone propionate, budesonide). Equivalent responses occurred in primary human bronchial epithelial cells. Concentrations of glucocorticoid plus LABA required to induce RGS2 expression in BEAS-2B cells were consistent with the levels achieved therapeutically in the lungs. As RGS2 is a GTPase-activating protein that switches off Gαq, intracellular free calcium ([Ca(2+)]i) flux was used as a surrogate of responses induced by histamine, methacholine, and the thromboxane receptor agonist U46619 [(Z)-7-[(1S,4R,5R,6S)-5-[(E,3S)-3-hydroxyoct-1-enyl]-3-oxabicyclo[2.2.1]heptan-6-yl]hept-5-enoic acid]. This was significantly attenuated by salmeterol plus dexamethasone pretreatment, or RGS2 overexpression, and the protective effect of salmeterol plus dexamethasone was abolished by RGS2 RNA silencing. Although methacholine and U46619 induced interleukin-8 (IL-8) release and this was inhibited by RGS2 overexpression, the repression of U46619-induced IL-8 release by salmeterol plus dexamethasone was unaffected by RGS2 knockdown. Given a role for Gαq-mediated pathways in inducing IL-8 release, we propose that RGS2 acts redundantly with other effector processes to repress IL-8 expression. Thus, RGS2 expression is a novel effector mechanism in the airway epithelium that is induced by glucocorticoid/LABA combinations. This could contribute to the efficacy of glucocorticoid/LABA combinations in asthma and COPD.
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Affiliation(s)
- Neil S Holden
- Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, Faculty of Medicine, University of Calgary, Calgary, Alberta, Canada (N.S.H., T.G., C.F.R., A.C., S.S., M.K., R.L., M.A.G., R.N.); GlaxoSmithKline Research and Development, Uxbridge, Middlesex, United Kingdom (M.J.); and Department of Physiology and Pharmacology, School of Medicine, West Virginia University, Morgantown, West Virginia (D.P.S.)
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Greer S, Page CW, Joshi T, Yan D, Newton R, Giembycz MA. Concurrent agonism of adenosine A2B and glucocorticoid receptors in human airway epithelial cells cooperatively induces genes with anti-inflammatory potential: a novel approach to treat chronic obstructive pulmonary disease. J Pharmacol Exp Ther 2013; 346:473-85. [PMID: 23820127 DOI: 10.1124/jpet.113.206284] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Chronic obstructive pulmonary disease (COPD) is a neutrophilic inflammatory disorder that is weakly responsive to glucocorticoids. Identification of ways to enhance the anti-inflammatory activity of glucocorticoids is, therefore, a major research objective. Adenosine receptor agonists that target the A2B-receptor subtype are efficacious in several cell-based assays and preclinical models of inflammation. Accordingly, the present study was designed to determine if a selective A2B-receptor agonist, 2-[6-amino-3,5-dicyano-4-[4-(cyclopropylmethoxy)phenyl]pyridin-2-ylsulphanyl]acetamide (Bay 60-6583), and a glucocorticoid, dexamethasone, in combination display putative anti-inflammatory activity that is superior to either drug alone. In BEAS-2B human airway epithelial cells stably transfected with cAMP-response element (CRE) and glucocorticoid response element (GRE) reporter constructs, Bay 60-6583 promoted CRE-dependent transcription and enhanced GRE-dependent transcription by an adenosine A2B-receptor-mediated mechanism that was associated with cAMP formation and abolished by an inhibitor of cAMP-dependent protein kinase. Analysis of the concentration-response relationship that described the enhancement of GRE-dependent transcription showed that Bay 60-6583 increased the magnitude of response without affecting the potency of dexamethasone. Bay 60-6583 and dexamethasone also induced a panel of genes that, collectively, could have benefit in COPD. These were categorized into genes that were induced in a positive cooperative manner (RGS2, p57(kip2)), an additive manner (TTP, BRL-1), or by Bay 60-6583 (CD200, CRISPLD2, SOCS3) or dexamethasone (GILZ) only. Thus, the gene induction "fingerprints" produced by Bay 60-6583 and dexamethasone, alone and in combination, were distinct. Collectively, through their actions on gene expression, an adenosine A2B-receptor agonist and a glucocorticoid administered together may have utility in the treatment of inflammatory disorders that respond suboptimally to glucocorticoids as a monotherapy.
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Affiliation(s)
- Stephanie Greer
- Airways Inflammation Research Group, Department of Physiology and Pharmacology, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada
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Rider CF, Miller-Larsson A, Proud D, Giembycz MA, Newton R. Modulation of transcriptional responses by poly(I:C) and human rhinovirus: effect of long-acting β₂-adrenoceptor agonists. Eur J Pharmacol 2013; 708:60-7. [PMID: 23523474 DOI: 10.1016/j.ejphar.2013.02.056] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2012] [Revised: 02/14/2013] [Accepted: 02/24/2013] [Indexed: 12/23/2022]
Abstract
Exacerbations of asthma, a chronic inflammatory respiratory disease, are associated with viral upper respiratory tract infections involving human rhinovirus. Although glucocorticoids (corticosteroids) effectively control airways inflammation in many asthmatics, human rhinovirus-associated exacerbations show reduced glucocorticoid responsiveness. Using human bronchial epithelial BEAS-2B cells, we show that human rhinovirus reduced glucocorticoid-inducible activation of glucocorticoid response element (GRE) reporter systems in a time- and concentration-dependent manner. The synthetic double-stranded viral RNA mimetic, polyinosinic:polycytidylic acid (poly(I:C)), also reduced activation of GRE reporter systems in BEAS-2B and pulmonary A549 cells. In addition, poly(I:C) decreased transcription from cAMP response element (CRE)-, TATA-, simian virus 40- and nuclear factor-kappa B (NF-κB)-dependent reporter systems. The effects of poly(I:C) on GRE-reporter activation were countered by the long-acting β2-adrenoceptor agonists, formoterol and salmeterol. Likewise, increased expression of the gene cyclin-dependent kinase inhibitor 1C (CDKN1C; p57(KIP2)) by dexamethasone was reduced by poly(I:C), but was substantially enhanced by the addition of formoterol. Poly(I:C) induced the expression of interleukin-8 (IL8; CXCL8) and this was significantly decreased by dexamethasone, formoterol or their combination. This confirms that not all transcriptional responses were attenuated by poly(I:C) and that decreased glucocorticoid-dependent transcription can be counteracted by the addition of long-acting β2-adrenoceptor agonists. These data show how human rhinovirus may attenuate glucocorticoid-induced transcription to reduce anti-inflammatory activity. However, addition of long-acting β2-adrenoceptor agonist to the glucocorticoid functionally restored this response and shows how glucocorticoid plus long-acting β2-adrenoceptor agonist combinations may prove beneficial during virus-induced exacerbations of asthma.
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Affiliation(s)
- Christopher F Rider
- Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, Faculty of Medicine, University of Calgary, Calgary, 3330 Hospital Drive NW, AB, Canada T2N 4N1.
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Moodley T, Wilson SM, Joshi T, Rider CF, Sharma P, Yan D, Newton R, Giembycz MA. Phosphodiesterase 4 Inhibitors Augment the Ability of Formoterol to Enhance Glucocorticoid-Dependent Gene Transcription in Human Airway Epithelial Cells: A Novel Mechanism for the Clinical Efficacy of Roflumilast in Severe Chronic Obstructive Pulmonary Disease. Mol Pharmacol 2013; 83:894-906. [DOI: 10.1124/mol.112.083493] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Kankaanranta H, de Souza PM, Giembycz MA, Lindsay MA. Human eosinophil isolation and the measurement of apoptosis. Methods Mol Med 2012; 44:99-110. [PMID: 21312124 DOI: 10.1385/1-59259-072-1:99] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Eosinophils have been implicated in allergic diseases, such as bronchial asthma, which is characterized by elevated eosinophil numbers in the bronchoalveolar lavage fluid and peripheral blood. Their accumulation and activation within the airway mucosa is thought to cause tissue injury, contraction of airway smooth muscle, and increased bronchial responsiveness (1-3). The balance between cell maturation and death is of great importance in determining the number of eosinophils in the blood and tissues (4-6). Following in vitro culture in the absence of cytokines, eosinophils undergo apoptosis, or programmed cell death (7,8), a process that can be inhibited by cytokines such as interleukin-3 and -5 and granulocyte-macrophage colony-stimulating factor (GM-CSF), and accelerated by such factors as corticosteroids and Fas (7-11).
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Affiliation(s)
- H Kankaanranta
- National Heart and Lung Institute, Imperial College School of Medicine, London, UK
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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Rider CF, King EM, Holden NS, Giembycz MA, Newton R. Inflammatory stimuli inhibit glucocorticoid-dependent transactivation in human pulmonary epithelial cells: rescue by long-acting beta2-adrenoceptor agonists. J Pharmacol Exp Ther 2011; 338:860-9. [PMID: 21622733 DOI: 10.1124/jpet.111.181016] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
By repressing inflammatory gene expression, glucocorticoids are the most effective treatment for chronic inflammatory diseases such as asthma. However, in some patients with severe disease, or who smoke or suffer from chronic obstructive pulmonary disease, glucocorticoids are poorly effective. Although many investigators focus on defects in the repression of inflammatory gene expression, glucocorticoids also induce (transactivate) the expression of numerous genes to elicit anti-inflammatory effects. Using human bronchial epithelial (BEAS-2B) and pulmonary (A549) cells, we show that cytokines [tumor necrosis factor α (TNFα) and interleukin 1β], mitogens [fetal calf serum (FCS) and phorbol ester], cigarette smoke, and a G(q)-linked G protein-coupled receptor agonist attenuate simple glucocorticoid response element (GRE)-dependent transcription. With TNFα and FCS, this effect was not overcome by increasing concentrations of dexamethasone, budesonide, or fluticasone propionate. Thus, the maximal ability of the glucocorticoid to promote GRE-dependent transcription was reduced, and this was shown additionally for the glucocorticoid-induced gene p57(KIP2). The long-acting β(2)-adrenoceptor agonists (LABAs) formoterol fumarate and salmeterol xinafoate enhanced simple GRE-dependent transcription to a level that could not be achieved by glucocorticoid alone. In the presence of TNFα or FCS, which repressed glucocorticoid responsiveness, these LABAs restored glucocorticoid-dependent transcription to levels that were achieved by glucocorticoid alone. Given the existence of genes, such as p57(KIP2), which may mediate anti-inflammatory actions of glucocorticoids, we propose that repression of transactivation represents a mechanism for glucocorticoid resistance and for understanding the clinical benefit of LABAs as an add-on therapy in asthma and chronic obstructive pulmonary disease.
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Affiliation(s)
- Christopher F Rider
- Airways Inflammation Research Group, Faculty of Medicine, University of Calgary, Calgary, Alberta, Canada
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Kankaanranta H, Parkkonen J, Ilmarinen-Salo P, Giembycz MA, Moilanen E. Salbutamol delays human eosinophil apoptosis via a cAMP-dependent mechanism. Pulm Pharmacol Ther 2011; 24:394-400. [PMID: 21396479 DOI: 10.1016/j.pupt.2011.03.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2010] [Revised: 12/14/2010] [Accepted: 03/01/2011] [Indexed: 11/27/2022]
Abstract
Eosinophils play a major role in asthma. One described mechanism leading to the impaired clearance of these cells from the lung is the delay in their programmed cell death (apoptosis). β(2)-Adrenoceptor agonists have been shown to prolong survival and delay apoptosis of eosinophils. The aim of the present study was to evaluate the mechanisms, especially the role of cAMP pathway, in the prolongation of human eosinophil survival by a selective β(2)-agonist salbutamol. Isolated human peripheral blood eosinophils were cultured in the absence or presence of a β(2)-agonist salbutamol and the indicated antagonists/inhibitors under sterile conditions. Apoptosis was measured by using the relative DNA fragmentation assay and Annexin-V binding. Salbutamol prolonged survival of human eosinophils and it was inhibited by a β-receptor antagonist propranolol and mimicked by cell-permeant cAMP analogues dibutyryl- and 8-bromo-cAMP. Pharmacological inhibitors of adenylyl cyclase (SQ-22,536) and protein kinase A (Rp-8-CPT-cAMPS) antagonized the effects of salbutamol. The survival-prolonging action of salbutamol was potentiated by a phosphodiesterase inhibitor rolipram (EC(50) for the salbutamol effect was 13.6 ± 4.0 and 8.1 ± 3.1 nM in the absence and presence of rolipram, respectively; p=0.0142, n=10). In contrast, inhibition of Ca(2+)-activated K(+)-channels by apamin, charybdotoxin, iberiotoxin or paxilline did not affect the ability of salbutamol to prolong eosinophil survival. Taken together, the present results suggest that salbutamol at clinically relevant concentrations decreases apoptosis in human eosinophils by activating the cannonical β(2)-receptor-adenylyl cyclase-cAMP-protein kinase A pathway.
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Affiliation(s)
- Hannu Kankaanranta
- The Immunopharmacology Research Group, Medical School/B, FIN-33014 University of Tampere, Tampere, Finland.
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Giembycz MA, Newton R. Harnessing the clinical efficacy of phosphodiesterase 4 inhibitors in inflammatory lung diseases: dual-selective phosphodiesterase inhibitors and novel combination therapies. Handb Exp Pharmacol 2011:415-446. [PMID: 21695651 DOI: 10.1007/978-3-642-17969-3_18] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Phosphodiesterase (PDE) 4 inhibitors have been in development as a novel anti-inflammatory therapy for more than 20 years, with asthma and chronic obstructive pulmonary disease (COPD) being primary indications. Despite initial optimism, only one selective PDE4 inhibitor, roflumilast (Daxas (®)), has been approved for use in humans and available in Canada and the European Union in 2011 for the treatment of a specific population of patients with severe COPD. In many other cases, the development of PDE4 inhibitors of various structural classes has been discontinued due to lack of efficacy and/or dose-limiting adverse events. Indeed, for many of these compounds, it is likely that the maximum tolerated dose is either subtherapeutic or at the very bottom of the efficacy dose-response curve. Thus, a significant ongoing challenge that faces the pharmaceutical industry is to synthesize compounds with therapeutic ratios that are superior to roflumilast. Several strategies are being considered, but clinically effective compounds with an optimal pharmacophore have not, thus far, been reported. In this chapter, alternative means of harnessing the clinical efficacy of PDE4 inhibitors are described. These concepts are based on the assumption that additive or synergistic anti-inflammatory effects can be produced with inhibitors that target either two or more PDE families or with a PDE4 inhibitor in combination with other anti-inflammatory drugs such as a glucocorticoid.
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Affiliation(s)
- Mark A Giembycz
- Airways Inflammation Research Group, Departments of Physiology and Pharmacology, Institute of Infection, Immunity and Inflammation, University of Calgary, 3280 Hospital Drive NW, Calgary, AB T2N 4N1, Canada.
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Wilson SM, Sheddan NA, Newton R, Giembycz MA. Evidence for a second receptor for prostacyclin on human airway epithelial cells that mediates inhibition of CXCL9 and CXCL10 release. Mol Pharmacol 2010; 79:586-95. [PMID: 21173040 DOI: 10.1124/mol.110.069674] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Herein we provide evidence for the coexpression of two distinct prostacyclin (PGI(2)) receptors (IP) on BEAS-2B human airway epithelial cells. IP receptor heterogeneity initially was suggested by the finding that the rank orders of potency of PGI(2) and three structurally similar analogs [taprostene, iloprost, 15-deoxy-16-(m-tolyl)-17,18,19,20-tetranorisocarbacyclin (15-deoxy-TIC)] for the inhibition of chemokine (CXCL9 and CXCL10) release and for transcriptional activation/augmentation of cAMP response element and glucocorticoid response element luciferase reporters were distinct. Indeed, PGI(2), taprostene, and iloprost activated both reporters whereas 15-deoxy-TIC was inert. Conversely, 15-deoxy-TIC, PGI(2), and taprostene (but not iloprost) suppressed chemokine release. Further experiments established that iloprost did not antagonize the inhibitory effect taprostene or 15-deoxy-TIC on chemokine output. Likewise, 15-deoxy-TIC failed to antagonize taprostene- and iloprost-induced reporter transactivation. Thus, iloprost- and 15-deoxy-TIC-induced responses were apparently mediated via pharmacologically distinct receptors. In human embryonic kidney 293 cells overexpressing the human recombinant IP receptor receptor, 15-deoxy-TIC was considerably less potent (>10,000-fold) than iloprost and taprostene in promoting cAMP accumulation, yet in BEAS-2B cells, these analogs were equipotent. IP receptor heterogeneity was also supported by the finding that the affinity of the IP receptor antagonist R-3-(4-fluorophenyl)-2-[5-(4-fluorophenyl)-benzofuran-2-yl-methoxycarbonyl-amino] propionic acid (RO3244794) for the receptor mediating inhibition of chemokine release was approximately 10-fold lower than for the receptor mediating both transcriptional outputs. Finally, small interfering RNAs directed against the IP receptor gene, PTGIR, failed to block the suppression of chemokine output induced by taprostene and 15-deoxy-TIC, whereas taprostene- and iloprost-induced transcriptional responses were markedly attenuated. Collectively, these results indicate that PGI(2), taprostene and 15-deoxy-TIC suppress chemokine release from BEAS-2B cells by interacting with a novel IP receptor that we denote here as the "IP(2)" subtype.
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Affiliation(s)
- Sylvia M Wilson
- Department of Physiology and Pharmacology, Faculty of Medicine, University of Calgary, Calgary, Alberta, Canada
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Abstract
In April 2010, the European Medicines Agency Committee for Medicinal Products for Human Use recommended approval of roflumilast, a selective phosphodiesterase 4 inhibitor, for the “maintenance treatment of severe chronic obstructive pulmonary disease (COPD, FEV1 postbronchodilator less than 50% predicted) associated with chronic bronchitis in adult patients with a history of frequent exacerbations as add-on to bronchodilator treatment”. This decision was based, in part, on the results of several large, international, multicenter, randomized, placebo-controlled trials of either six or 12 months’ duration that had been undertaken in COPD patients. Roflumilast 500 μg daily improved lung function and reduced exacerbations in patients with more severe COPD, especially those with chronic bronchitis, frequent exacerbations, or who required frequent rescue inhaler therapy in the placebo-controlled trials. It also improved lung function and reduced exacerbations in patients with moderately severe COPD treated with salmeterol or tiotropium. Advantages of roflumilast over inhaler therapy are that it is an oral tablet and only needs to be taken once daily. While taking roflumilast, the most common adverse effects patients experienced were gastrointestinal upset and headache. Weight loss, averaging 2.2 kg, occurred in patients treated with roflumilast. Patients taking roflumilast were more likely to drop out of the trials than patients in the control groups. Patients who discontinued therapy usually did so during the first few weeks and were more likely to have experienced gastrointestinal side effects. Roflumilast is the first selective phosphodiesterase 4 inhibitor and will offer physicians another treatment option for patients with more severe COPD.
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Affiliation(s)
- Mark A Giembycz
- Department of Physiology and Pharmacology, Faculty of Medicine, University of Calgary, Alberta, Canada
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Gross NJ, Giembycz MA, Rennard SI. Treatment of Chronic Obstructive Pulmonary Disease with Roflumilast, a New Phosphodiesterase 4 Inhibitor. COPD 2010; 7:141-53. [DOI: 10.3109/15412551003758304] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Newton R, Leigh R, Giembycz MA. Pharmacological strategies for improving the efficacy and therapeutic ratio of glucocorticoids in inflammatory lung diseases. Pharmacol Ther 2009; 125:286-327. [PMID: 19932713 DOI: 10.1016/j.pharmthera.2009.11.003] [Citation(s) in RCA: 78] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2009] [Accepted: 11/02/2009] [Indexed: 10/20/2022]
Abstract
Glucocorticoids are widely used to treat various inflammatory lung diseases. Acting via the glucocorticoid receptor (GR), they exert clinical effects predominantly by modulating gene transcription. This may be to either induce (transactivate) or repress (transrepress) gene transcription. However, certain individuals, including those who smoke, have certain asthma phenotypes, chronic obstructive pulmonary disease (COPD) or some interstitial diseases may respond poorly to the beneficial effects of glucocorticoids. In these cases, high dose, often oral or parental, glucocorticoids are typically prescribed. This generally leads to adverse effects that compromise clinical utility. There is, therefore, a need to enhance the clinical efficacy of glucocorticoids while minimizing adverse effects. In this context, a long-acting beta(2)-adrenoceptor agonist (LABA) can enhance the clinical efficacy of an inhaled corticosteroid (ICS) in asthma and COPD. Furthermore, LABAs can augment glucocorticoid-dependent gene expression and this action may account for some of the benefits of LABA/ICS combination therapies when compared to ICS given as a monotherapy. In addition to metabolic genes and other adverse effects that are induced by glucocorticoids, there are many other glucocorticoid-inducible genes that have significant anti-inflammatory potential. We therefore advocate a move away from the search for ligands of GR that dissociate transactivation from transrepression. Instead, we submit that ligands should be functionally screened by virtue of their ability to induce or repress biologically-relevant genes in target tissues. In this review, we discuss pharmacological methods by which selective GR modulators and "add-on" therapies may be exploited to improve the clinical efficacy of glucocorticoids while reducing potential adverse effects.
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Affiliation(s)
- Robert Newton
- Department of Cell Biology and Anatomy, Airway Inflammation Group, Institute of Infection, Immunity and Inflammation, Faculty of Medicine, University of Calgary, Calgary, Alberta, Canada.
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Wilson SM, Shen P, Rider CF, Traves SL, Proud D, Newton R, Giembycz MA. Selective prostacyclin receptor agonism augments glucocorticoid-induced gene expression in human bronchial epithelial cells. J Immunol 2009; 183:6788-99. [PMID: 19880449 DOI: 10.4049/jimmunol.0902738] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Prostacyclin receptor (IP-receptor) agonists display anti-inflammatory and antiviral activity in cell-based assays and in preclinical models of asthma and chronic obstructive pulmonary disease. In this study, we have extended these observations by demonstrating that IP-receptor activation also can enhance the ability of glucocorticoids to induce genes with anti-inflammatory activity. BEAS-2B bronchial epithelial cells stably transfected with a glucocorticoid response element (GRE) luciferase reporter were activated in a concentration-dependent manner by the glucocorticoid dexamethasone. An IP-receptor agonist, taprostene, increased cAMP in these cells and augmented luciferase expression at all concentrations of dexamethasone examined. Analysis of the concentration-response relationship that described this effect showed that taprostene increased the magnitude of transcription without affecting the potency of dexamethasone and was, thus, steroid-sparing in this simple system. RO3244794, an IP-receptor antagonist, and oligonucleotides that selectively silenced the IP-receptor gene, PTGIR, abolished these effects of taprostene. Infection of BEAS-2B GRE reporter cells with an adenovirus vector encoding a highly selective inhibitor of cAMP-dependent protein kinase (PKA) also prevented taprostene from enhancing GRE-dependent transcription. In BEAS-2B cells and primary cultures of human airway epithelial cells, taprostene and dexamethasone interacted either additively or cooperatively in the expression of three glucocorticoid-inducible genes (GILZ, MKP-1, and p57(kip2)) that have anti-inflammatory potential. Collectively, these data show that IP-receptor agonists can augment the ability of glucocorticoids to induce anti-inflammatory genes in human airway epithelial cells by activating a cAMP/PKA-dependent mechanism. This observation may have clinical relevance in the treatment of airway inflammatory diseases that are either refractory or respond suboptimally to glucocorticoids.
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Affiliation(s)
- Sylvia M Wilson
- Department of Physiology and Pharmacology, Faculty of Medicine, University of Calgary, Calgary, Alberta, Canada
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Cowie RL, Giembycz MA, Leigh R. Mometasone furoate: an inhaled glucocorticoid for the management of asthma in adults and children. Expert Opin Pharmacother 2009; 10:2009-14. [PMID: 19618993 DOI: 10.1517/14656560903078428] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Mometasone furoate has been available for clinical use, starting with a dermatologic preparation, for nearly 20 years. An inhaled format of the drug for management of asthma had been in development during the last decade and has been available for clinical use for 6 years as a dry powder inhaler delivering either 100 mcg or 200 mcg per dose. It has a long half-life and is suitable for daily dosing. The drug is approved for use in the USA for the treatment of asthma in patients aged 4 years or over. Mometasone furoate is a topically potent glucocorticoid with a favorable risk-benefit profile. A wide variety of randomized clinical trials have shown the drug to have a clinically beneficial effect on asthma comparable to fluticasone propionate, and to permit the reduction or withdrawal of oral glucocorticoid therapy in patients with asthma. Mometasone furoate has approximately 1% oral bioavailability but does produce systemic glucocorticoid effects from the drug released from the lung and its metabolites. These effects are minimal when mometasone is used appropriately at low or moderate doses.
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Affiliation(s)
- Robert L Cowie
- Faculty of Medicine, University of Calgary, Institute of Infection, Immunity and Inflammation, Department of Medicine, 3280 Hospital Drive NW, Calgary, Alberta, Canada.
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Kroegel C, Warner JA, Giembycz MA, Matthys H, Lichtenstein LM, Barnes PJ. Dual Transmembrane Signalling Mechanisms in Eosinophils: Evidence for Two Functionally Distinct Receptors for Platelet-Activating Factor. Int Arch Allergy Immunol 2009; 99:226-229. [DOI: 10.1159/000236253] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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Jones RL, Giembycz MA, Woodward DF. Prostanoid receptor antagonists: development strategies and therapeutic applications. Br J Pharmacol 2009; 158:104-45. [PMID: 19624532 PMCID: PMC2795261 DOI: 10.1111/j.1476-5381.2009.00317.x] [Citation(s) in RCA: 128] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2009] [Accepted: 04/07/2009] [Indexed: 01/17/2023] Open
Abstract
Identification of the primary products of cyclo-oxygenase (COX)/prostaglandin synthase(s), which occurred between 1958 and 1976, was followed by a classification system for prostanoid receptors (DP, EP(1), EP(2) ...) based mainly on the pharmacological actions of natural and synthetic agonists and a few antagonists. The design of potent selective antagonists was rapid for certain prostanoid receptors (EP(1), TP), slow for others (FP, IP) and has yet to be achieved in certain cases (EP(2)). While some antagonists are structurally related to the natural agonist, most recent compounds are 'non-prostanoid' (often acyl-sulphonamides) and have emerged from high-throughput screening of compound libraries, made possible by the development of (functional) assays involving single recombinant prostanoid receptors. Selective antagonists have been crucial to defining the roles of PGD(2) (acting on DP(1) and DP(2) receptors) and PGE(2) (on EP(1) and EP(4) receptors) in various inflammatory conditions; there are clear opportunities for therapeutic intervention. The vast endeavour on TP (thromboxane) antagonists is considered in relation to their limited pharmaceutical success in the cardiovascular area. Correspondingly, the clinical utility of IP (prostacyclin) antagonists is assessed in relation to the cloud hanging over the long-term safety of selective COX-2 inhibitors. Aspirin apart, COX inhibitors broadly suppress all prostanoid pathways, while high selectivity has been a major goal in receptor antagonist development; more targeted therapy may require an intermediate position with defined antagonist selectivity profiles. This review is intended to provide overviews of each antagonist class (including prostamide antagonists), covering major development strategies and current and potential clinical usage.
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Affiliation(s)
- R L Jones
- Strathclyde Institute of Pharmacy & Biomedical Sciences, University of Strathclyde, Glasgow, UK.
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Freund-Michel VC, Birrell MA, Giembycz MA, Hele DJ, Haj-Yahia S, Belvisi MG. Beta(2)-agonists block tussive responses in guinea pigs via an atypical cAMP-dependent pathway. Eur Respir J 2009; 35:647-54. [PMID: 19679606 DOI: 10.1183/09031936.00034009] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
beta(2)-Adrenoceptor agonists are the most effective bronchodilators currently available, and are used for symptom management in asthmatics. However, whether beta(2)-agonists are also antitussive is controversial. Identifying an antitussive role for beta(2)-agonists and dissecting the possible mechanism of action may help to explain the inconsistencies in the clinical literature and lead to the development of novel therapeutic agents. The aim of the present study was to determine whether or not beta(2)-agonists attenuate the tussive response in guinea pig and human models, and, if so, to identify the mechanism(s) involved. Depolarisation of vagal sensory nerves (human and guinea pig) was assessed as an indicator of sensory nerve activity. Cough was measured in a conscious guinea pig model. A beta(2)-agonist, terbutaline, dose-dependently inhibited the cough response to tussive agents in conscious guinea pigs. Terbutaline and another beta(2)-agonist, fenoterol, blocked sensory nerve activation in vitro. Using these mechanistic models, it was established that beta(2)-agonists suppress the tussive response via a nonclassical cyclic adenosine monosphosphate-dependent pathway that involves the activation of protein kinase G and, subsequently, the opening of large-conductance calcium-activated potassium channels. In conclusion, beta(2)-adrenoceptor agonists are antitussive, and this property occurs due to a direct inhibition of sensory nerve activation. These findings may help to explain the confusion that exists in the clinical literature, and could be exploited to identify novel therapies for the treatment of cough, which is a significant unmet medical need.
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Abstract
BACKGROUND AND PURPOSE The beta(2)-adrenoceptor on human pro-inflammatory cells is exquisitely sensitive to desensitization, whereas beta(2)-adrenoceptor-mediated relaxation of human airways smooth muscle (HASM) is relatively resistant to this phenomenon. An explanation for this discrepancy is that a large beta(2)-adrenoceptor 'reserve' exists on HASM cells for sympathomimetic bronchodilators, which protects against desensitization. EXPERIMENTAL APPROACH The operational model of agonism was used to estimate the affinity of salbutamol, terbutaline, formoterol and procaterol for the beta(2)-adrenoceptors in methacholine (MCh)-contracted HASM from which the relationship between fractional receptor occupancy and relaxation was determined. This analysis was performed under conditions of fractional, irreversible, beta(2)-adrenoceptor inactivation and, for salbutamol and terbutaline only, by the comparative method of Barlow et al. The affinity of salbutamol for the beta(2)-adrenoceptor guinea-pig eosinophils and the receptor/occupancy-response relationship for the suppression of the respiratory burst (an index of pro-inflammatory cell function) was also determined. KEY RESULTS For salbutamol and terbutaline, both pharmacological approaches yielded in HASM discrepant affinity estimates (values differed, maximally, by 0.67 log(10) unit). However, affinity values more closely agreed (difference <0.47 log(10) unit), when operational analysis was performed on data corrected for 'fade' of the MCh-induced contraction. Plots of fractional beta(2)-adrenoceptor occupancy versus relaxation indicated a receptor 'reserve' for all agonists tested at all levels of response. In contrast, minimal receptor reserve was detected for the ability of salbutamol to suppress respiratory burst activity in eosinophils. CONCLUSIONS AND IMPLICATIONS These data may help explain the relative inability of sympathomimetic bronchodilators to render HASM tolerant to beta(2)-adrenoceptor-mediated relaxation.
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Affiliation(s)
- Mark A Giembycz
- Department of Physiology & Pharmacology, Institute of Infection, Immunity and Inflammation, Faculty of Medicine, University of Calgary, Calgary, AB, Canada.
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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Koetzler R, Zaheer RS, Wiehler S, Holden NS, Giembycz MA, Proud D. Nitric oxide inhibits human rhinovirus-induced transcriptional activation of CXCL10 in airway epithelial cells. J Allergy Clin Immunol 2008; 123:201-208.e9. [PMID: 18986693 DOI: 10.1016/j.jaci.2008.09.041] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2008] [Revised: 08/25/2008] [Accepted: 09/29/2008] [Indexed: 12/16/2022]
Abstract
BACKGROUND Human rhinovirus (HRV) infections trigger exacerbations of asthma and chronic obstructive pulmonary disease. Nitric oxide (NO) inhibits HRV replication in human airway epithelial cells and suppresses HRV-induced epithelial production of several cytokines and chemokines. OBJECTIVE We sought to delineate the mechanisms by which NO inhibits HRV-induced epithelial production of CXCL10, a chemoattractant for type 1 T cells and natural killer cells. METHODS Primary human bronchial epithelial cells or cells of the BEAS-2B human bronchial epithelial cell line were exposed to HRV-16 in the presence or absence of the NO donor 3-(2-hydroxy-2-nitroso-1-propylhydrazino)-1-propanamine (PAPA NONOate). A cGMP analogue and an inhibitor of soluble guanylyl cyclase were used to examine the role of the cyclic guanosine monophosphate (cGMP) pathway in the actions of NO. BEAS-2B cells were transfected with CXCL10 promoter-luciferase constructs and the effects of PAPA NONOate were examined to study mechanisms of transcriptional regulation. Electrophoretic mobility shift assays were also used. RESULTS PAPA NONOate inhibited HRV-16-induced increases in CXCL10 mRNA and protein. Inhibition of CXCL10 production occurred through a cGMP-independent pathway. PAPA NONOate inhibited HRV-16-induced CXCL10 transcription by blocking nuclear translocation, binding, or both of both nuclear factor kappaB and IFN response factors (IRFs) to their respective recognition elements in the CXCL10 promoter. CONCLUSIONS NO inhibits HRV-16-induced production of CXCL10 by inhibiting viral activation of nuclear factor kappaB and of IRFs, including IRF-1, through a cGMP-independent pathway. The broad-ranging inhibition of HRV-induced epithelial cytokine and chemokine production by NO suggests a potential therapeutic utility of NO donors in viral exacerbations of asthma and chronic obstructive pulmonary disease.
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Affiliation(s)
- Rommy Koetzler
- Airway Inflammation Group, Institute of Infection, Immunity and Inflammation, University of Calgary, Calgary, Alberta, Canada
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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