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Safavi S, Thorpe J, Haywood B, Barlow M, Hall IP. P43 Hyperpolarised xenon-129 MRI of lungs in healthy volunteers: a safety & feasibility study. Thorax 2016. [DOI: 10.1136/thoraxjnl-2016-209333.186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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2
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Miller S, Melén E, Merid SK, Hall IP, Sayers I. Genes associated with polymorphic variants predicting lung function are differentially expressed during human lung development. Respir Res 2016; 17:95. [PMID: 27473260 PMCID: PMC4966770 DOI: 10.1186/s12931-016-0410-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Accepted: 07/20/2016] [Indexed: 01/20/2023] Open
Abstract
BACKGROUND Recent meta-analyses of genome-wide association studies have identified single nucleotide polymorphisms (SNPs) within/near 54 genes associated with lung function measures. Current understanding of the contribution of these genes to human lung development is limited. We set out to further define i) the expression profile of these genes during human lung development using a unique set of resources to examine both mRNA and protein expression and ii) the link between key polymorphisms and genes using expression quantitative trait loci (eQTL) approaches. METHODS The mRNA expression profile of lung function associated genes across pseudoglandular and canalicular stages of lung development were determined using expression array data of 38 human fetal lungs. eQTLs were investigated for selected genes using blood cell and lung tissue data. Immunohistochemistry of the top 5 candidates was performed in a panel of 24 fetal lung samples. RESULTS Twenty-nine lung function associated genes were differentially expressed during lung development at the mRNA level. The greatest magnitude of effect was observed for 5 genes; TMEM163, FAM13A and HHIP which had increasing expression and CDC123 and PTCH1 with decreased expression across developmental stages. Focussed eQTL analyses investigating SNPs in these five loci identified several cis-eQTL's. Protein expression of TMEM163 increased and CDC123 decreased with fetal lung age in agreement with mRNA data. Protein expression in FAM13A, HHIP and PTCH1 remained relatively constant throughout lung development. CONCLUSIONS We have identified that > 50 % of lung function associated genes show evidence of differential expression during lung development and we show that in particular TMEM163 and CDC123 are differentially expressed at both the mRNA and protein levels. Our data provides a systematic evaluation of lung function associated genes in this context and offers some insight into the potential role of several of these genes in contributing to human lung development.
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Affiliation(s)
- S Miller
- Division of Respiratory Medicine, Queen's Medical Centre, University of Nottingham, Nottingham, NG7 2UH, UK.
| | - E Melén
- Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden.,Sachs' Children's Hospital, Stockholm, Sweden
| | - S K Merid
- Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden
| | - I P Hall
- Division of Respiratory Medicine, Queen's Medical Centre, University of Nottingham, Nottingham, NG7 2UH, UK
| | - I Sayers
- Division of Respiratory Medicine, Queen's Medical Centre, University of Nottingham, Nottingham, NG7 2UH, UK
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Thorgeirsson TE, Steinberg S, Reginsson GW, Bjornsdottir G, Rafnar T, Jonsdottir I, Helgadottir A, Gretarsdottir S, Helgadottir H, Jonsson S, Matthiasson SE, Gislason T, Tyrfingsson T, Gudbjartsson T, Isaksson HJ, Hardardottir H, Sigvaldason A, Kiemeney LA, Haugen A, Zienolddiny S, Wolf HJ, Franklin WA, Panadero A, Mayordomo JI, Hall IP, Rönmark E, Lundbäck B, Dirksen A, Ashraf H, Pedersen JH, Masson G, Sulem P, Thorsteinsdottir U, Gudbjartsson DF, Stefansson K. A rare missense mutation in CHRNA4 associates with smoking behavior and its consequences. Mol Psychiatry 2016; 21:594-600. [PMID: 26952864 PMCID: PMC5414061 DOI: 10.1038/mp.2016.13] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/22/2015] [Revised: 12/17/2015] [Accepted: 01/04/2016] [Indexed: 11/22/2022]
Abstract
Using Icelandic whole-genome sequence data and an imputation approach we searched for rare sequence variants in CHRNA4 and tested them for association with nicotine dependence. We show that carriers of a rare missense variant (allele frequency=0.24%) within CHRNA4, encoding an R336C substitution, have greater risk of nicotine addiction than non-carriers as assessed by the Fagerstrom Test for Nicotine Dependence (P=1.2 × 10(-4)). The variant also confers risk of several serious smoking-related diseases previously shown to be associated with the D398N substitution in CHRNA5. We observed odds ratios (ORs) of 1.7-2.3 for lung cancer (LC; P=4.0 × 10(-4)), chronic obstructive pulmonary disease (COPD; P=9.3 × 10(-4)), peripheral artery disease (PAD; P=0.090) and abdominal aortic aneurysms (AAAs; P=0.12), and the variant associates strongly with the early-onset forms of LC (OR=4.49, P=2.2 × 10(-4)), COPD (OR=3.22, P=2.9 × 10(-4)), PAD (OR=3.47, P=9.2 × 10(-3)) and AAA (OR=6.44, P=6.3 × 10(-3)). Joint analysis of the four smoking-related diseases reveals significant association (P=6.8 × 10(-5)), particularly for early-onset cases (P=2.1 × 10(-7)). Our results are in agreement with functional studies showing that the human α4β2 isoform of the channel containing R336C has less sensitivity for its agonists than the wild-type form following nicotine incubation.
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Affiliation(s)
- T E Thorgeirsson
- deCODE genetics/Amgen, Reykjavik, Iceland,deCODE genetics/Amgen, Sturlugata 8, Reykjavik IS-101, Iceland. E-mail: or
| | | | | | | | - T Rafnar
- deCODE genetics/Amgen, Reykjavik, Iceland
| | - I Jonsdottir
- deCODE genetics/Amgen, Reykjavik, Iceland,Faculty of Medicine, University of Iceland, Reykjavik, Iceland
| | | | | | | | - S Jonsson
- Faculty of Medicine, University of Iceland, Reykjavik, Iceland,Department of Respiratory Medicine, Landspitali University Hospital, Reykjavik, Iceland
| | | | - T Gislason
- Faculty of Medicine, University of Iceland, Reykjavik, Iceland,Department of Respiratory Medicine, Landspitali University Hospital, Reykjavik, Iceland
| | - T Tyrfingsson
- SAA National Center of Addiction Medicine, Reykjavik, Iceland
| | - T Gudbjartsson
- Faculty of Medicine, University of Iceland, Reykjavik, Iceland,Department of Cardiothoracic Surgery, Landspitali University Hospital, Reykjavik, Iceland
| | - H J Isaksson
- Department of Pathology, Landspitali University Hospital, Reykjavik, Iceland
| | - H Hardardottir
- Department of Respiratory Medicine, Landspitali University Hospital, Reykjavik, Iceland
| | - A Sigvaldason
- Department of Respiratory Medicine, Landspitali University Hospital, Reykjavik, Iceland
| | - L A Kiemeney
- Radboud Institute for Health Sciences, Radboud University Medical Center, Nijmegen, The Netherlands,Department of Urology, Radboud University Medical Center, Nijmegen, The Netherlands
| | - A Haugen
- Department for the Chemical and Biological Work Environment, National Institute of Occupational Health, Oslo, Norway
| | - S Zienolddiny
- Department for the Chemical and Biological Work Environment, National Institute of Occupational Health, Oslo, Norway
| | - H J Wolf
- Community & Behavioral Health, Colorado School of Public Health, University of Colorado Denver, Aurora, CO, USA
| | - W A Franklin
- Department of Pathology, University of Colorado Denver, Aurora, CO, USA
| | - A Panadero
- Division of Medical Oncology, Hospital Ciudad de Coria, Coria, Spain
| | - J I Mayordomo
- Division of Medical Oncology, University of Colorado School of Medicine, Denver, CO, USA
| | - I P Hall
- Division of Respiratory Medicine, Queens Medical Centre, University of Nottingham, Nottingham, UK
| | - E Rönmark
- The OLIN studies, Department of Medicine, Sunderby Central Hospital of Norrbotten, Luleå, Sweden,Faculty of Medicine, Department of Public Health and Clinical Medicine, Occupational and Environmental Medicine, Umeå University, Umeå, Sweden
| | - B Lundbäck
- The OLIN studies, Department of Medicine, Sunderby Central Hospital of Norrbotten, Luleå, Sweden,Krefting Research Centre, Institute of Medicine, The Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - A Dirksen
- Department of Respiratory Medicine, Gentofte Hospital, Copenhagen University, Hellerup, Denmark
| | - H Ashraf
- Department of Respiratory Medicine, Gentofte Hospital, Copenhagen University, Hellerup, Denmark,Centre for Diagnostic Imaging—Thoracic Section, Akershus University Hospital, Loerenskog, Norway
| | - J H Pedersen
- Department of Thoracic Surgery RT, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - G Masson
- deCODE genetics/Amgen, Reykjavik, Iceland
| | - P Sulem
- deCODE genetics/Amgen, Reykjavik, Iceland
| | | | | | - K Stefansson
- deCODE genetics/Amgen, Reykjavik, Iceland,Faculty of Medicine, University of Iceland, Reykjavik, Iceland,deCODE genetics/Amgen, Sturlugata 8, Reykjavik IS-101, Iceland. E-mail: or
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Koppelman GH, Hall IP. Asthma genetics 2014: reaching for high-hanging fruit. Clin Exp Allergy 2015; 44:1296-8. [PMID: 25332085 DOI: 10.1111/cea.12420] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- G H Koppelman
- Department of Pediatric Pulmonology and Pediatric Allergology and GRIAC Research Institute, University Medical Center Groningen, University of Groningen, Beatrix Children's Hospital, Groningen, The Netherlands
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Donaldson JW, McKeever TM, Hall IP, Hubbard RB, Fogarty AW. The UK prevalence of hereditary haemorrhagic telangiectasia and its association with sex, socioeconomic status and region of residence: a population-based study. Thorax 2013; 69:161-7. [PMID: 24188926 DOI: 10.1136/thoraxjnl-2013-203720] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
BACKGROUND Hereditary haemorrhagic telangiectasia (HHT) is an autosomal dominant genetic disorder of aberrant blood vessel development characterised by arteriovenous malformations. HHT is associated with significant morbidity due to complications including epistaxis, gastrointestinal bleeding and stroke. We explored the hypothesis that a diagnosis of HHT is associated with sex, socioeconomic status and geographical location. METHODS We used The Health Improvement Network, a longitudinal, computerised general practice database covering 5% of the UK population to calculate prevalence estimates for HHT stratified by age, sex, socioeconomic status and geographical location. RESULTS The 2010 UK point prevalence for HHT was 1.06/10 000 person years (95% CI 0.95 to 1.17) or 1 in 9400 individuals. The diagnosed prevalence of HHT was significantly higher in women compared with men (adjusted prevalence rate ratio (PRR) 1.53, 95% CI 1.24 to 1.88) and in those from the most affluent socioeconomic group compared with the least (adjusted PRR 1.74, 95% CI 1.14 to 2.64). The PRR varied between different regions of the UK, being highest in the South West and lowest in the West Midlands (adjusted PRR for former compared with latter 1.86, 95% CI 1.61 to 2.15). CONCLUSIONS HHT prevalence is more common in the UK population than previously demonstrated, though this updated figure is still likely to be an underestimate. HHT appears to be significantly under-diagnosed in men, which is likely to reflect their lower rates of consultation with primary care services. There is under-diagnosis in patients from lower socioeconomic groups and a marked variation in the prevalence of diagnosis between different geographical regions across the UK that requires further investigation.
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Affiliation(s)
- J W Donaldson
- Division of Epidemiology and Public Health, University of Nottingham, , Nottingham, UK
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6
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C Dewar J, P Wheatley A, P Hall I. Methods for Determining β(2)-Adrenoreceptor Genotype. Methods Mol Med 2012; 44:253-73. [PMID: 21312135 DOI: 10.1385/1-59259-072-1:253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Polymorphisms of the β(2)-adrenoceptor (β(2)AR) have been the focus of much interest as part of the search to elucidate the genetic basis of asthma and allergic disease. More recently, these polymorphisms have also been implicated in the genetic etiology of essential hypertension (1,2) and obesity (3,4). This chapter describes in detail the method of allele-specific-oligonucleotide hybridization (ASO), a technique that has been used extensively by the authors' group to determine β(2)AR genotype. This method should prove useful not only to those intending to analyze β(2)AR polymorphisms, but also for the analysis of other candidate genes, given that this technique can be adapted and applied to any known single-base mutation.
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7
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Wan YI, Shrine NRG, Soler Artigas M, Wain LV, Blakey JD, Moffatt MF, Bush A, Chung KF, Cookson WOCM, Strachan DP, Heaney L, Al-Momani BAH, Mansur AH, Manney S, Thomson NC, Chaudhuri R, Brightling CE, Bafadhel M, Singapuri A, Niven R, Simpson A, Holloway JW, Howarth PH, Hui J, Musk AW, James AL, Brown MA, Baltic S, Ferreira MAR, Thompson PJ, Tobin MD, Sayers I, Hall IP. Genome-wide association study to identify genetic determinants of severe asthma. Thorax 2012; 67:762-8. [PMID: 22561531 DOI: 10.1136/thoraxjnl-2011-201262] [Citation(s) in RCA: 138] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
BACKGROUND The genetic basis for developing asthma has been extensively studied. However, association studies to date have mostly focused on mild to moderate disease and genetic risk factors for severe asthma remain unclear. OBJECTIVE To identify common genetic variants affecting susceptibility to severe asthma. METHODS A genome-wide association study was undertaken in 933 European ancestry individuals with severe asthma based on Global Initiative for Asthma (GINA) criteria 3 or above and 3346 clean controls. After standard quality control measures, the association of 480 889 genotyped single nucleotide polymorphisms (SNPs) was tested. To improve the resolution of the association signals identified, non-genotyped SNPs were imputed in these regions using a dense reference panel of SNP genotypes from the 1000 Genomes Project. Then replication of SNPs of interest was undertaken in a further 231 cases and 1345 controls and a meta-analysis was performed to combine the results across studies. RESULTS An association was confirmed in subjects with severe asthma of loci previously identified for association with mild to moderate asthma. The strongest evidence was seen for the ORMDL3/GSDMB locus on chromosome 17q12-21 (rs4794820, p=1.03×10((-8)) following meta-analysis) meeting genome-wide significance. Strong evidence was also found for the IL1RL1/IL18R1 locus on 2q12 (rs9807989, p=5.59×10((-8)) following meta-analysis) just below this threshold. No novel loci for susceptibility to severe asthma met strict criteria for genome-wide significance. CONCLUSIONS The largest genome-wide association study of severe asthma to date was carried out and strong evidence found for the association of two previously identified asthma susceptibility loci in patients with severe disease. A number of novel regions with suggestive evidence were also identified warranting further study.
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Affiliation(s)
- Y I Wan
- Therapeutics and Molecular Medicine, University of Nottingham, Nottingham, UK.
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8
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Soler Artigas M, Wain LV, Tobin MD, Hall IP. Joint Effect of Single-Nucleotide Polymorphisms and Smoking Exposure in Chronic Obstructive Pulmonary Disease Risk. Am J Respir Crit Care Med 2012. [DOI: 10.1164/ajrccm.185.6.683a] [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: 11/16/2022] Open
Affiliation(s)
| | - L. V. Wain
- University of LeicesterLeicester, United Kingdom
| | - M. D. Tobin
- University of LeicesterLeicester, United Kingdom
| | - I. P. Hall
- University of NottinghamNottingham, United Kingdom
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9
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John M, Hussain S, Selvarajah S, Sayers I, Hall IP, Fairclough L, Bolton CE. P40 Increased advanced glycation end products in patients with chronic obstructive pulmonary disease (COPD). Thorax 2011. [DOI: 10.1136/thoraxjnl-2011-201054c.40] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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10
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Roberts ME, Magowan L, Hall IP, Johnson SR. Discoidin domain receptor 1 regulates bronchial epithelial repair and matrix metalloproteinase production. Eur Respir J 2010; 37:1482-93. [PMID: 20884741 DOI: 10.1183/09031936.00039710] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Discoidin domain receptor (DDR)1 is an extracellular matrix (ECM)-sensing receptor tyrosine kinase, which is activated by collagen and expressed in bronchial epithelium. DDR1 is responsible for maintaining the normal structure of skin and kidney epithelia and we hypothesised that DDR1 plays a regulatory role in bronchial epithelial integrity by transducing signals from the airway ECM. Effects of DDR1 depletion were studied using RNA interference in primary human bronchial epithelial cells (HBECs) and BEAS-2B cells. The effects of overexpression of DDR1a and DDR1b in BEAS-2B cells were studied using a plasmid vector. We measured the effects on epithelial repair using a scratch wounding model, and levels of matrix metalloproteinases (MMPs) by gelatin zymography (MMP-2 and -9) and ELISA (MMP-7). We showed that knockdown of DDR1 slowed epithelial repair by 50%, which was associated with a reduction in levels of MMP-7, whilst DDR1 overexpression enhanced epithelial repair. DDR1 knockdown reduced proliferation of HBECs, but had no significant effect on adhesion to collagen I or other matrix substrates. These data suggest that ECM signalling via DDR1 regulates aspects of bronchial epithelial repair, integrity and MMP expression in the airways.
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Affiliation(s)
- M E Roberts
- Division of Therapeutics and Molecular Medicine, Respiratory Biomedical Research Unit, University of Nottingham, D Floor South Block, Queen's Medical Centre, Nottingham, NG7 2UH, UK
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11
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Beghé B, Hall IP, Parker SG, Moffatt MF, Wardlaw A, Connolly MJ, Fabbri LM, Ruse C, Sayers I. Polymorphisms in IL13 pathway genes in asthma and chronic obstructive pulmonary disease. Allergy 2010; 65:474-81. [PMID: 19796199 DOI: 10.1111/j.1398-9995.2009.02167.x] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.8] [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: 11/30/2022]
Abstract
BACKGROUND Asthma and chronic obstructive pulmonary disease (COPD) are chronic respiratory diseases involving an interaction between genetic and environmental factors. Interleukin-13 (IL13) has been suggested to have a role in both asthma and COPD. We investigated whether single nucleotide polymorphisms (SNPs) in the IL13 pathway may contribute to the susceptibility and severity of asthma and COPD in adults. METHODS Twelve SNPs in IL13 pathway genes -IL4, IL13, IL4RA, IL13RA1, IL13RA2 and STAT6- were genotyped in subjects with asthma (n = 299) and in subjects with COPD or healthy smokers (n = 992). Genetic association was evaluated using genotype and allele models for asthma severity, atopy phenotypes and COPD susceptibility. Linear regression was used to determine the effects of polymorphism on baseline lung function (FEV(1), FEV(1)/FVC). RESULTS In asthmatics, three IL13 SNPs - rs1881457(-1512), rs1800925(-1111) and rs20541(R130Q) - were associated with atopy risk. One SNP in IL4RA1 [rs1805010(I75V)] was associated with asthma severity, and several IL13 SNPs showed borderline significance. IL13 SNPs rs1881457(-1512) and rs1800925(-1111) were associated with better FEV(1) and FEV(1)/FVC in asthmatics. IL13 SNPs rs2066960(intron 1), rs20541(R130Q) and rs1295685(exon 4) were associated with COPD risk and lower baseline lung function in the recessive model. In females, but not in males, rs2250747 of the IL13RA1 gene was associated with COPD and lower FEV(1). CONCLUSION These data suggest that IL13 SNPs (promoter and coding region) and, to a lesser extent, IL4RA SNPs may contribute to atopy and asthma. We also provide tentative evidence that IL13 SNPs in the coding region may be of significance in COPD susceptibility.
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Affiliation(s)
- B Beghé
- Department of Oncology, Haematology and Respiratory Diseases, University of Modena and Reggio Emilia, Italy
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Brook BS, Peel SE, Hall IP, Politi AZ, Sneyd J, Bai Y, Sanderson MJ, Jensen OE. A biomechanical model of agonist-initiated contraction in the asthmatic airway. Respir Physiol Neurobiol 2010; 170:44-58. [PMID: 19932770 DOI: 10.1016/j.resp.2009.11.006] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [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] [Received: 06/11/2009] [Revised: 11/16/2009] [Accepted: 11/17/2009] [Indexed: 10/24/2022]
Abstract
This paper presents a modelling framework in which the local stress environment of airway smooth muscle (ASM) cells may be predicted and cellular responses to local stress may be investigated. We consider an elastic axisymmetric model of a layer of connective tissue and circumferential ASM fibres embedded in parenchymal tissue and model the active contractile force generated by ASM via a stress acting along the fibres. A constitutive law is proposed that accounts for active and passive material properties as well as the proportion of muscle to connective tissue. The model predicts significantly different contractile responses depending on the proportion of muscle to connective tissue in the remodelled airway. We find that radial and hoop-stress distributions in remodelled muscle layers are highly heterogenous with distinct regions of compression and tension. Such patterns of stress are likely to have important implications, from a mechano-transduction perspective, on contractility, short-term cytoskeletal adaptation and long-term airway remodelling in asthma.
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Affiliation(s)
- B S Brook
- School of Mathematical Sciences, University Park, University of Nottingham, Nottingham, UK.
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Sayers I, Hawley J, Stewart CE, Billington CK, Henry A, Leighton-Davies JR, Charlton SJ, Hall IP. Pharmacogenetic characterization of indacaterol, a novel beta 2-adrenoceptor agonist. Br J Pharmacol 2009; 158:277-86. [PMID: 19422388 DOI: 10.1111/j.1476-5381.2009.00224.x] [Citation(s) in RCA: 14] [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: 11/26/2022] Open
Abstract
BACKGROUND AND PURPOSE Indacaterol is a novel beta(2)-adrenoceptor agonist in development for the treatment of chronic obstructive pulmonary disease. The aim of this study was to investigate the comparative pharmacology of indacaterol in recombinant cells expressing the common polymorphic variants of the human beta(2)-adrenoceptor and in human primary airway smooth muscle (ASM) cells. EXPERIMENTAL APPROACH Chinese hamster ovarian-K1 cell lines expressing high and low levels of the common human beta(2)-adrenoceptor variants were generated [Gly16-Glu27-Val34-Thr164(GEVT), RQVT, GQVT] and also the rare GQVI variant. Human primary ASM cells were isolated from explants of trachealis muscle. Adenosine-3',5'-cyclic-monophosphate production was used as an outcome measure. KEY RESULTS In both the low- and high-expression recombinant GEVT 'wild type' cell lines indacaterol is a high-efficacy agonist. Salmeterol and formoterol were identified as low- and high-efficacy agonists, respectively, and showed similar potencies to indacaterol irrespective of the beta(2)-adrenoceptor genotype. The I164 variant cell line was associated with a reduced capacity to generate adenosine-3',5'-cyclic-monophosphate in response to beta(2)-adrenoceptor agonist. In the human primary ASM cells indacaterol gave a maximal response intermediate between that of salmeterol and formoterol. CONCLUSIONS AND IMPLICATIONS These data demonstrate that indacaterol is a high-efficacy agonist in recombinant cell systems but acts with lower efficacy in human primary ASM cells. No marked genotype-dependent effects were observed for common variants; however, changes in I164 receptor activity were identified, which were dependent on the level of expression of beta(2)-adrenoceptors.
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Affiliation(s)
- I Sayers
- Division of Therapeutics & Molecular Medicine, University Hospital of Nottingham, Nottingham, UK.
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14
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Blakey JD, Sayers I, Ring SM, Strachan DP, Hall IP. Positionally cloned asthma susceptibility gene polymorphisms and disease risk in the British 1958 Birth Cohort. Thorax 2009; 64:381-7. [PMID: 19237393 DOI: 10.1136/thx.2008.102053] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
OBJECTIVE The aim of this study was to estimate the contribution of polymorphisms in the positionally cloned asthma candidate genes ADAM33, PHF11, DPP10, GPRA and PTGDR to the risk of asthma, total and specific immunoglobulin E level, lung function and wheezing in a large, nationally representative, population. METHODS An association analysis was undertaken using genotype data for tagging and previously associated single nucleotide polymorphisms (SNPs) in regions of these genes and longitudinal phenotype data from singletons of white ethnicity in the British 1958 Birth Cohort DNA archive (n = 7703). Population-attributable risk fractions for SNPs showing association were calculated. RESULTS Polymorphisms producing small but statistically significant increases in asthma risk (OR 1.1 per allele) were identified in DPP10 and ADAM33, with the strongest evidence being for SNPs tagging the DPP10 gene. No individual SNP in any gene under study markedly increased risk for any of the phenotypes in the population studied. CONCLUSIONS These data suggest that DPP10 and ADAM33 influence asthma risk in the UK population. However, the effects driven by any given locus are small, and genotyping of multiple polymorphisms in many genes will be needed to define a full genetic profile for disease risk.
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15
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Hall IP. Natriuretic peptides and asthma: is there a connection? Clin Exp Allergy 2008; 38:1068-70. [PMID: 18498419 DOI: 10.1111/j.1365-2222.2008.03013.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Abstract
Pharmacogenetic approaches provide the opportunity to improve prescribing for asthmatic patients in order to optimise efficacy and prevent side-effects. Currently, there are comprehensive data available on the extent of genetic variation in the human genome that will further this area of research. However, less is known about the functional consequences of many of the identified polymorphisms in genes whose products may predict drug efficacy. In addition, there is a shortage of well-designed, adequately powered clinical studies in this area. This series summarises the current state of knowledge and identifies areas for further research.
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Affiliation(s)
- I P Hall
- Division of Therapeutics and Molecular Medicine, University Hospital of Nottingham, Nottingham, NG7 2UH, UK.
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Hidalgo-Bastida LA, Barry JJA, Everitt NM, Rose FRAJ, Buttery LD, Hall IP, Claycomb WC, Shakesheff KM. Cell adhesion and mechanical properties of a flexible scaffold for cardiac tissue engineering. Acta Biomater 2007; 3:457-62. [PMID: 17321810 DOI: 10.1016/j.actbio.2006.12.006] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.9] [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: 03/21/2006] [Revised: 12/07/2006] [Accepted: 12/12/2006] [Indexed: 11/20/2022]
Abstract
Cardiac tissue engineering is focused on obtaining functional cardiomyocyte constructs to provide an alternative to cellular cardiomyoplasty. Mechanical stimuli have been shown to stimulate protein expression and the differentiation of mammalian cells from contractile tissues. Our aim was to obtain a flexible scaffold which could be used to apply mechanical forces during tissue regeneration. Poly(1,8-octanediol-co-citric acid) (POC) is an elastomer that can be processed into scaffolds for tissue engineering. We investigated the effect of modifying the porosity on the mechanical properties of the POC scaffolds. In addition, the effects of the storage method and strain rate on material integrity were assessed. The maximum elongation of POC porous films varied from 60% to 160% of their original length. A decrease in the porosity caused a rise in this elastic modulus. The attachment of HL-1 cardiomyocytes to POC was assessed on films coated with fibronectin, collagen and laminin. These extracellular matrix proteins promoted cell adhesion in a protein-type- and concentration-dependent manner. Therefore, POC scaffolds can be optimised to meet the mechanical and biological parameters needed for cardiac culture. This porous material has the potential to be used for cardiac tissue engineering as well as for other soft tissue applications.
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Affiliation(s)
- L A Hidalgo-Bastida
- Division of Drug Delivery and Tissue Engineering, School of Pharmacy, University of Nottingham, Nottingham NG7 2RD, UK
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18
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Abstract
BACKGROUND Hyponatraemia is the most commonly identified electrolyte abnormality. Published data on severe hyponatraemia in general medical in-patients is lacking. AIM To determine the aetiology, adequacy of assessment, and outcome of severe hyponatraemia in general medical in-patients. DESIGN Retrospective case-note review. METHODS All general medical in-patients (n = 108) with serum sodium < or =125 mmol/l were identified from the clinical chemistry database, over a six-month period. A full review of notes and computer records was undertaken at the index date and a pre-determined follow-up date. RESULTS Follow-up data were available in 105 patients. There was a wide range of aetiologies: diuretic therapy (loop and thiazide), congestive cardiac failure and liver disease were the most common, and 75.3% of patients had multiple causes. None of the 48% of patients whose history suggested a possible diagnosis of the syndrome of inappropriate anti-diuretic hormone (SIADH) met the generally accepted diagnostic criteria. Overall mortality was 20% during the index admission and 44.6% at follow-up, vs. 7.1% and 22%, respectively, for other patients admitted to the same directorate over the same time period (p < 0.001). Mortality was linked to aetiology, but not to reduced absolute serum sodium concentration at admission. DISCUSSION Severe hyponatraemia in general medical patients is associated with a complex, multifactoral aetiology and a very poor prognosis. Outlook is governed principally by aetiology, and not by serum sodium level. Assessment of patients with hyponatraemia requires a practical clinical algorithm for diagnosing SIADH.
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Affiliation(s)
- J A Clayton
- Division of Therapeutics and Molecular Medicine, Queen's Medical Centre, Nottingham NG7 2UH.
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19
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Abstract
AIMS Thiazide diuretics have a number of well-documented metabolic adverse effects. The aim of this study was to estimate the frequency of hyponatraemia and hypokalaemia amongst patients taking a thiazide diuretic in primary care. METHODS A computerized search of the electronic prescribing and laboratory records of six UK general practices was performed. Of the 32 218 adult patients identified, 3773 had received at least one prescription for a thiazide between the years 1990 and 2002. RESULTS Detailed prescribing data were available for 2942 patients of whom 951 (32.3%) had a recorded check of their electrolytes. One hundred and ninety-six (20.6%) had a sodium and/or potassium concentration below the normal range. The sodium distribution had a negative skew (-1.8) and in 130 (13.7%) patients was within the hyponatraemic range. Hypokalaemia was less common, occurring in 79 (8.5%) patients. Hyponatraemia was significantly associated with increased age; the odds ratio for developing hyponatraemia in patients over 70 years was 3.87 compared with those of < or = 70 years. Hypokalaemia was significantly associated with increased thiazide dose. CONCLUSIONS Prescription of a thiazide diuretic in primary care is associated with a high frequency of hyponatraemia and hypokalaemia. Thiazides should be prescribed at low dose and the risk of hyponatraemia, especially in the elderly, should be considered and monitored for when prescribing these agents.
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Affiliation(s)
- J A Clayton
- Division of Therapeutics and Molecular Medicine, University Hospital, Queen's Medical Centre, Nottingham, UK.
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20
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Green RH, Brightling CE, McKenna S, Hargadon B, Neale N, Parker D, Ruse C, Hall IP, Pavord ID. Comparison of asthma treatment given in addition to inhaled corticosteroids on airway inflammation and responsiveness. Eur Respir J 2006; 27:1144-51. [PMID: 16455831 DOI: 10.1183/09031936.06.00102605] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
There is increasing evidence that the assessment of eosinophilic airway inflammation using induced sputum and measurement of airway hyperresponsiveness provides additional, clinically important information concerning asthma control. The aim of this study was to directly compare the effects of different treatments on these markers in patients with asthma and persistent symptoms, despite the use of low-dose inhaled corticosteroids. A double-blind four-way crossover study was performed, which compared a 1-month treatment with budesonide 400 mug b.i.d., additional formoterol, additional montelukast and placebo in 49 patients with uncontrolled asthma despite budesonide 100 mug b.i.d., with each treatment separated by a 4-week washout period. The change in sputum eosinophil count with formoterol (2.4 to 3.8% change, 0.6-fold reduction, 95% confidence interval (CI) 0.5-0.9) differed significantly from placebo (2.8 to 2.5% change, 1.1-fold reduction, 95% CI 0.7-1.6) and high-dose budesonide (2.7 to 1.6% change, 1.6-fold reduction, 95% CI 1.2-2.2). The effects of montelukast did not differ from placebo. The changes in methacholine airway responsiveness were small and did not differ between treatments. High-dose budesonide had the broadest range of beneficial effects on other outcomes, including symptom scores, morning peak expiratory flow and forced expiratory volume in one second. In conclusion, treatment given in addition to low-dose inhaled corticosteroids results in modest benefits. Formoterol and high-dose budesonide have contrasting effects on eosinophilic airway inflammation.
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Affiliation(s)
- R H Green
- Institute for Lung Health, Dept of Respiratory Medicine and Thoracic Surgery, Glenfield Hospital, Groby Road, Leicester LE3 9PQ, UK
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21
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Abstract
BACKGROUND The beta2-adrenoceptor exhibits genetic polymorphism which may be clinically relevant in terms of treatment response or bronchial hyper-responsiveness (BHR). The combined effect of these genotypes, or the haplotype, has not been fully characterized in terms of BHR. METHODS We performed a retrospective analysis of the effects of haplotypes of amino acid substitution at position 16 (Gly/Arg) and position 27 (Gln/Glu) on spirometry and BHR to methacholine and adenosine monophosphate (AMP) in 594 asthmatic patients. RESULTS There was a significant (P < 0.05) overall effect for forced expiratory volume (FEV(1)) but not after correction for steroid dose and atopic status. There were no significant differences for BHR to methacholine or AMP between the different haplotypes and no difference between the numbers of patients with or without clinically relevant BHR. Methacholine PD20 geometric mean-fold difference was 1.63 (95% CI: 0.95-2.80) between Arg-Arg/Gln-Gln and Gly-Gly/Gln-Gln and 1.26 (95% CI: 0.75-2.11) between Gly-Gly/Gln-Gln and Gly-Gly/Glu-Glu. CONCLUSIONS The degree of BHR to indirect and direct stimuli does not differ between beta2-adrenoceptor haplotypes, and haplotypes cannot be used to predict BHR in patients presenting with asthma. Although beta2-adrenoceptor haplotypes do not predict BHR they may be important in predicting response to bronchodilator therapy.
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Affiliation(s)
- A M Wilson
- Biomedicine Group, School of Medicine, Health Policy and Practice, University of East Anglia, Norwich, UK
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23
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Blakey J, Halapi E, Bjornsdottir US, Wheatley A, Kristinsson S, Upmanyu R, Stefansson K, Hakonarson H, Hall IP. Contribution of ADAM33 polymorphisms to the population risk of asthma. Thorax 2005; 60:274-6. [PMID: 15790980 PMCID: PMC1747383 DOI: 10.1136/thx.2004.027227] [Citation(s) in RCA: 101] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
BACKGROUND ADAM 33 is the first gene identified as a candidate for asthma by positional cloning techniques, with association studies reaching impressive statistical significance. It has a postulated role in myogenesis, airway modelling, and signalling via protein shedding. Concerns over the methodology of the initial study have led to several attempts at replication, with inconsistent results. METHOD To clarify the role of ADAM33 in determining the risk of asthma in the general population, new transmission disequilibrium and case-control studies were undertaken followed by a meta-analysis of all existing data. RESULTS Studies in Icelandic and UK populations revealed no association when taken in isolation. The meta-analysis, however, showed that the F+1 and ST+7 variants were significantly associated with asthma in both types of study. CONCLUSIONS The additional risk imparted by this variation would account for 50,000 excess asthma cases in the UK alone. This study also demonstrates the size of study required to investigate such hypotheses adequately.
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Affiliation(s)
- J Blakey
- Division of Therapeutics and Molecular Medicine, University Hospital of Nottingham, Nottingham, UK
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24
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Abstract
Expression profiling approaches are potentially valuable in helping to define novel gene products which may be important in disease pathogenesis or treatment response. However, there are many pitfalls which need to be considered in the design of experiments of this kind and in considering interpretation of data from such studies. Some of these are discussed.
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Affiliation(s)
- I P Hall
- Division of Therapeutics and Molecular Medicine, D Floor, South Block, Queen's Medical Centre, Nottingham NG7 2UH, UK.
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25
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Abstract
Asthma is one of the commonest chronic diseases of affluent societies. The striking increase in prevalence of asthma over recent decades and the rarity of this disease in less affluent populations confirms the importance of environmental factors in the cause of asthma--although which environmental factors are responsible is still not clear. Family studies show that genetic factors are also important in determining individual susceptibility to asthma, with results of genetic studies suggesting that there are many genes with moderate effects rather than a few major genes. Asthmatic airways show inflammation and remodelling, with CD4+ helper cells, mast cells, and eosinophils characterising the inflammatory response. Inhaled corticosteroids remain the cornerstone of treatment with the addition of long-acting beta agonists as the next step if symptoms continue. Leukotriene antagonists, the only new drugs to reach the market in the past decade, have modest effects. However, a better understanding of the mechanisms underlying asthma and the genetic and environmental factors that predispose individuals to asthma should lead to better preventative strategies and new therapeutic approaches.
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Affiliation(s)
- A E Tattersfield
- Division of Respiratory Medicine, Clinical Sciences Building, City Hospital, Nottingham, UK.
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26
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Glynn PC, Henney E, Hall IP. The selective CXCR2 antagonist SB272844 blocks interleukin-8 and growth-related oncogene-alpha-mediated inhibition of spontaneous neutrophil apoptosis. Pulm Pharmacol Ther 2002; 15:103-10. [PMID: 12090783 DOI: 10.1006/pupt.2001.0323] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The aims of this study were to investigate the effects of Interleukin-8 (IL-8) and Growth related oncogene-alpha (Gro-alpha) on neutrophil apoptosis and determine the potential for a selective CXCR2 antagonist to inhibit these responses. IL-8 and Gro-alpha both produced dose dependent inhibition of spontaneous human neutrophil apoptosis after 16 hours incubation (59+/-3.5% and 27.5+/-3% respectively; EC50s 2.2+/-1.8 nM, and 0.5+/-0.2 nM respectively). The pro-survival effect of a fixed concentration of agonist (IL-8 or Gro-alpha) on cultured neutrophils was abrogated by a selective CXCR2 antagonist SB272844 (K(D)s 253 nM and 49.9 nM in the presence of IL-8 or Gro-alpha respectively). Our data suggests that the anti-apoptotic effect of Gro-alpha is mediated through CXCR2 as selective CXCR2 blockade with SB272844 can potently abrogate this response. The inhibitory effect of IL-8 may in addition partly be mediated through CXCR1 as SB272844 was less potent in its ability to abrogate the anti-apoptotic effects of IL-8 when this agent was used as an agonist. CXCR2 antagonists may have a therapeutic role in controlling neutrophil-driven inflammation by reducing neutrophil recruitment and restoring neutrophils to the tissue clearance pathway of apoptosis.
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Affiliation(s)
- P C Glynn
- Division of Therapeutics, University of Nottingham South Block, C Floor, Queens Medical Centre, Nottingham, NG7 2UH
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27
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Lipworth B, Koppelman GH, Wheatley AP, Le Jeune I, Coutie W, Meurs H, Kauffman HF, Postma DS, Hall IP. Beta2 adrenoceptor promoter polymorphisms: extended haplotypes and functional effects in peripheral blood mononuclear cells. Thorax 2002; 57:61-6. [PMID: 11809992 PMCID: PMC1746184 DOI: 10.1136/thorax.57.1.61] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.1] [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: 11/03/2022]
Abstract
BACKGROUND The beta2 adrenoceptor and its 5' untranslated region contain a number of genetic variants. The aim of this study was to investigate the potential for genetic variation at this locus to influence the expression of beta2 adrenoceptors on circulating peripheral blood mononuclear cells (PBMCs). METHODS Genotype was determined in 96 individuals with asthma for four polymorphisms at the beta2 adrenoceptor locus. Beta2 adrenoceptor binding and cyclic AMP responses to isoprenaline in PBMCs were determined and the relationship between genotype/haplotype and beta2 adrenoceptor expression and response to isoprenaline examined. RESULTS Beta2 adrenoceptor promoter polymorphisms were found to be common in white subjects. Strong linkage disequilibrium exists across this locus, resulting in the occurrence of several common haplotypes. No single polymorphism or haplotype was correlated with the level of beta2 adrenoceptor expression or cyclic AMP responses to isoprenaline in vitro. CONCLUSION Beta2 adrenoceptor polymorphisms, when considered in isolation or by extended haplotypes, do not determine the basal level of expression or coupling of beta2 adrenoceptors in PBMCs from asthmatic subjects.
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Affiliation(s)
- B Lipworth
- Asthma and Allergy Research Group, Clinical Pharmacology and Therapeutics, Ninewells Hospital and Medical School, Dundee DD1 9SY, UK
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28
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Pascual RM, Billington CK, Hall IP, Panettieri RA, Fish JE, Peters SP, Penn RB. Mechanisms of cytokine effects on G protein-coupled receptor-mediated signaling in airway smooth muscle. Am J Physiol Lung Cell Mol Physiol 2001; 281:L1425-35. [PMID: 11704539 DOI: 10.1152/ajplung.2001.281.6.l1425] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.6] [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: 11/22/2022] Open
Abstract
Numerous in vitro and in vivo studies have implicated the cytokines interleukin-1 beta (IL-1 beta) and tumor necrosis factor-alpha (TNF-alpha) as mediators of airway inflammation and therefore potentially important substances in the pathogenesis of asthma. In this study, we examined the mechanisms by which IL-1 beta and TNF-alpha affect inhibition of cell growth, G protein-coupled receptor (GPCR) desensitization, and the recently reported adenylyl cyclase sensitization in human airway smooth muscle (HASM) cultures. Our findings demonstrate that adenylyl cyclase sensitization is independent of cytokine-mediated cyclooxygenase type 2 (COX-2) and prostaglandin E(2) (PGE(2)) induction, whereas COX-2 induction appears to be required for both growth inhibition and GPCR desensitization. However, GPCR desensitization was highly dependent on the presence of EGF during chronic treatment with cytokines, which could be explained by a synergistic effect of EGF on cytokine-mediated COX-2 and PGE(2) induction. Interestingly, various agents (including inhibitors of p42/p44 and p38 mitogen-activated protein kinase signaling) were significantly more effective in inhibiting cytokine-mediated PGE(2) induction, GPCR desensitization, and cell growth inhibition than in inhibiting COX-2 induction. These data demonstrate disparity in the requirement and sufficiency of COX-2 induction in promoting different functional effects of IL-1 beta and TNF-alpha in HASM.
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Affiliation(s)
- R M Pascual
- Division of Critical Care, Pulmonary, Allergic, and Immunological Diseases, Department of Medicine, Jefferson Medical College, Thomas Jefferson University, Philadelphia, PA 19107, USA
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29
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Freyer AM, Johnson SR, Hall IP. Effects of growth factors and extracellular matrix on survival of human airway smooth muscle cells. Am J Respir Cell Mol Biol 2001; 25:569-76. [PMID: 11713098 DOI: 10.1165/ajrcmb.25.5.4605] [Citation(s) in RCA: 105] [Impact Index Per Article: 4.6] [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: 01/13/2023] Open
Abstract
Airway remodeling complicates longstanding asthma. It is characterized by an increase in the number of airway smooth muscle cells (SMCs) as well as an increase in and alteration of the type of extra-cellular matrix (ECM) in the airways. Although the number of SMCs in the airways depends on the balance of cell proliferation and cell death, studies to date have concentrated on factors affecting SMC proliferation. Here we report the first study on airway SMC survival factors: these cells receive a strong survival signal, which is not dependent on the known growth factor mitogens. We identified the ECM factors fibronectin, laminin, and collagens I and IV as important anti-apoptotic elements, and characterized the expression of the ECM receptors (integrins) on cultured SMC. Functionally blocking antibody and peptide studies revealed the alpha(5)beta(1) integrin to be an important transducer of the ECM-derived survival signal in these cells. Confocal microscopy confirmed the striking effects that discrete ECM factors have on SMC phenotype, notably the cytoskeleton. In summary, our data improves the understanding of the mechanisms underlying airway remodeling by outlining the key survival factors for airway SMC and by highlighting the impact of the cell-matrix interactions on cell death and phenotype.
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Affiliation(s)
- A M Freyer
- Division of Therapeutics and Institute of Cell Signalling, University Hospital, Nottingham, United Kingdom.
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Xu D, Isaacs C, Hall IP, Emala CW. Human airway smooth muscle expresses 7 isoforms of adenylyl cyclase: a dominant role for isoform V. Am J Physiol Lung Cell Mol Physiol 2001; 281:L832-43. [PMID: 11557587 DOI: 10.1152/ajplung.2001.281.4.l832] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [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: 11/22/2022] Open
Abstract
Adenylyl cyclases are a nine-member family of differentially regulated enzymes responsible for the synthesis of cAMP. cAMP is an important second messenger that contributes to the regulation of airway smooth muscle tone. However, little is known regarding the expression and regulation of adenylyl cyclase isoforms in airway smooth muscle cells. Nondegenerate specific primers were designed for all nine known isoforms of human adenylyl cyclase. RT-PCR experiments were performed using total RNA extracted from whole human brain (positive control), whole rat brain (negative control), whole human trachea, human airway smooth muscle, and primary cultures of human airway smooth muscle cells. Seven of the nine known isoforms of adenylyl cyclase (isoforms I, III-VII, and IX) were expressed at the mRNA level in both human airway smooth muscle and primary cultures of human airway smooth muscle cells. Immunoblot and adenylyl cyclase functional assay indicated that isoform V is likely among the functionally predominant isoforms of adenylyl cyclase in human airway smooth muscle. These results suggest that multiple isoforms of adenylyl cyclase enzymes are coexpressed in human airway smooth muscle cells and that isoform V is among the functionally important isoforms.
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Affiliation(s)
- D Xu
- Department of Anesthesiology, College of Physicians and Surgeons of Columbia University, New York, New York 10032, USA
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31
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Abstract
Cryptogenic fibrosing alveolitis (CFA) is characterized by increased pulmonary recruitment of peripheral blood neutrophils (PBNs) by interleukin (IL)-8 and other chemotactic mediators. This study investigated whether, in CFA, the PBN motility response is primed by IL-8 and growth-related oncogene (Gro)-alpha, as demonstrated in other neutrophilic inflammatory diseases, and whether the motility response of PBNs to IL-8 and Gro-alpha can be abrogated using a selective antagonist for the neutrophil receptor for IL-8 and Gro-alpha, CXCR2. The percentage of PBNs to undergo shape change (%SC), spontaneously and in response to IL-8 and Gro-alpha, was measured in patients with CFA (n=10) and controls (n=10), and the effect of the CXCR2 antagonist SB272844 studied. Plasma levels of IL-8, and Gro-alpha were measured using an enzyme-linked immunosorbent assay (ELISA). The %SC of unstimulated PBNs and the potency of Gro-alpha and IL-8 to produce neutrophil polarization was greater in CFA than in controls; dose which produces 50% of maximal effect (EC50) of IL-8 was 3.6 +/- 0.7 nM for CFA versus 6.3 +/- 1.0 nM for controls; p<0.05. SB272844 inhibited Gro-alpha induced but not IL-8 induced neutrophil shape change (equilibrium constant (KD) 123 +/- 18 nM). Plasma concentrations of Gro-alpha were increased in patients with CFA. PBNs are spontaneously activated and undergo a greater motility response to IL-8 and Gro-alpha in CFA. Interleukin-8 and growth-related oncogene-alpha, circulating in substimulatory amounts in cryptogenic fibrosing alveolitis, may prime the peripheral blood neutrophils motility response, thus increasing their capacity for migration to the lung. Selective CXCR2 antagonists may be useful to block the Gro-alpha-induced priming response whilst preserving neutrophil functions mediated by CXCR1, the alternative neutrophil receptor for interleukin-8.
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Affiliation(s)
- P C Glynn
- Division of Therapeutics, University Hospital of Nottingham, UK
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32
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Hall IP. Chronic lung diseases--Institut Pasteur Euroconference. IDrugs 2001; 4:1021-4. [PMID: 15965847] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Affiliation(s)
- I P Hall
- Division of Therapeutics, C Floor, South Block, University Hospital of Nottingham, Nottingham, NG7 2UH, UK.
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33
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Cho SH, Hall IP, Wheatley A, Dewar J, Abraha D, Del Mundo J, Lee H, Oh CK. Possible role of the 4G/5G polymorphism of the plasminogen activator inhibitor 1 gene in the development of asthma. J Allergy Clin Immunol 2001; 108:212-4. [PMID: 11496236 DOI: 10.1067/mai.2001.117260] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- S H Cho
- Division of Allergy and Immunology, the Department of Pediatrics, Harbor-UCLA Medical Center, School of Medicine, University of California, Los Angeles, Torrance 90509, USA
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Billington CK, Pascual RM, Hawkins ML, Penn RB, Hall IP. Interleukin-1beta and rhinovirus sensitize adenylyl cyclase in human airway smooth-muscle cells. Am J Respir Cell Mol Biol 2001; 24:633-9. [PMID: 11350835 DOI: 10.1165/ajrcmb.24.5.4215] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [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: 11/24/2022] Open
Abstract
Rhinovirus (RV) is a major cause of wheezing in asthmatics and has been reported to cause beta2 adrenergic receptor hyporesponsiveness in human airway smooth muscle (HASM) via cellular secretion of interleukin (IL)-1beta. We studied the effects of IL-1beta and RV on cyclic adenosine monophosphate (cAMP) production in HASM cells. Chronic incubation with IL-1beta or RV caused a significant increase (approximately 3- and approximately 2-fold, respectively) in forskolin (FSK)-stimulated cAMP production, suggesting a sensitization of adenylyl cyclase (AC). The observed augmentation of FSK-stimulated cAMP formation by IL-1beta was completely abrogated by pretreatment with an IL-1 receptor antagonist or cycloheximide, demonstrating that the effect is mediated via the IL-1 receptor 1 (IL-1R1) and that de novo protein synthesis is required. In contrast, RV-induced AC sensitization was not mediated via the IL-1R1 but was observed to be protein kinase C-dependent. We suggest that the sensitization of AC observed after exposure to IL-1beta or RV infection is a cellular defense mechanism to promote pathways that induce relaxation in the inflamed airway.
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MESH Headings
- Adenylate Cyclase Toxin
- Adenylyl Cyclases/metabolism
- Adrenergic beta-Agonists/pharmacology
- Cells, Cultured
- Colforsin/pharmacology
- Cyclic AMP/metabolism
- Cycloheximide/pharmacology
- Dose-Response Relationship, Drug
- Enzyme Activation/drug effects
- Enzyme Inhibitors/pharmacology
- Feedback
- GTP-Binding Protein alpha Subunits, Gi-Go/antagonists & inhibitors
- Humans
- Interleukin 1 Receptor Antagonist Protein
- Interleukin-1/pharmacology
- Muscle, Smooth/cytology
- Muscle, Smooth/drug effects
- Muscle, Smooth/enzymology
- Muscle, Smooth/virology
- Picornaviridae Infections/enzymology
- Protein Kinase C/antagonists & inhibitors
- Protein Kinase C/metabolism
- Protein Synthesis Inhibitors/pharmacology
- Receptors, Interleukin-1/antagonists & inhibitors
- Receptors, Interleukin-1/metabolism
- Receptors, Interleukin-1 Type I
- Rhinovirus/metabolism
- Sialoglycoproteins/pharmacology
- Trachea
- Virulence Factors, Bordetella/pharmacology
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Affiliation(s)
- C K Billington
- Division of Therapeutics & Institute of Cell Signalling, and Public Health Laboratory, University Hospital of Nottingham, Nottingham, United Kingdom
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35
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Fenech AG, Ebejer MJ, Felice AE, Ellul-Micallef R, Hall IP. Mutation screening of the muscarinic M(2) and M(3) receptor genes in normal and asthmatic subjects. Br J Pharmacol 2001; 133:43-8. [PMID: 11325793 PMCID: PMC1572756 DOI: 10.1038/sj.bjp.0704039] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [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] [Indexed: 11/09/2022] Open
Abstract
1. Muscarinic receptors are important in the development of airway hyperresponsiveness, and dysfunction of these receptors has been suggested to be present in asthma. 2. The human muscarinic M(2) and M(3) receptor genes were screened for polymorphic variation using single-stranded conformation polymorphism (SSCP) analysis, complemented by direct fluorescent sequencing. Forty-six random DNA samples and 46 respiratory physician diagnosed asthmatic samples were used as a template for analysis. 3. Within the muscarinic M(2) receptor gene, we identified two degenerate single base substitutions (1197T-->C, Thr-->Thr and 976A-->C, Arg-->Arg) in one random and one asthmatic sample respectively. Analysis of the 3' UTR region revealed an additional 'A' at bp 1793 (c.f. ATG). This was present in all of 49 samples analysed by sequencing or BsmI digest, suggesting that the published sequence (GenBank Accession NO: M16404) is incorrect. A common 3' UTR polymorphism (T-->A) was found at bp 1696 (c.f. ATG) (allelic frequency=65%, n=60), but this does not alter transcription factor recognition sites. 4. We were unable to identify any polymorphic variation within the muscarinic M(3) coding region or the flanking regions investigated, using the methods described. 5. The coding regions for the human muscarinic M(2) and M(3) receptor genes are both highly conserved. These data suggest that polymorphic variation within these coding sequences is unlikely to account for inter-individual variability in response to methacholine or anticholinergic therapy. The potential functional significance of the muscarinic M(2) receptor 3' UTR polymorphism (bp 1696) remains to be determined.
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Affiliation(s)
- A G Fenech
- Department of Clinical Pharmacology and Therapeutics, University of Malta, Msida MSD 06, Malta
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Holloway JW, Lonjou C, Beghé B, Peng Q, Gaunt TR, Gomes I, Hall IP, Dewar JC, Wilkinson J, Thomas NS, Holgate ST, Morton NE. Linkage analysis of the 5q31-33 candidate region for asthma in 240 UK families. Genes Immun 2001; 2:20-4. [PMID: 11294563 DOI: 10.1038/sj.gene.6363723] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [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: 11/08/2022]
Abstract
Atopy and asthma are complex genetic diseases resulting from the interactions of a number of genetic and environmental factors. We had previously reported allelic association between the IL9 marker on chromosome 5q31-33 and atopy. In order to further investigate the role of susceptibility genes on 5q31-33 in the development of atopy and asthma we have studied 240 UK families comprising 131 families selected at random, 60 multiplex families with affected sib pairs, and 49 single proband nuclear families. Polymorphic markers on 5q31-33 were genotyped and both single and multipoint linkage analysis was undertaken using the BETA program. We have used both affection status and quantitative scores for atopy and asthma for phenotypic variables, combining data into scores for asthma and atopy. The strongest suggestion of linkage using multipoint analysis was centred around D5S410 with a maximum Lod of 1.946 at location 171.3 cM and a standard error of 3.3 for the asthma quantitative score. There was no evidence of linkage with atopy, the atopy quantitative score or total serum IgE.
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Affiliation(s)
- J W Holloway
- Human Genetics, Division School of Medicine, University of Southampton, UK.
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Lonjou C, Barnes K, Chen H, Cookson WO, Deichmann KA, Hall IP, Holloway JW, Laitinen T, Palmer LJ, Wjst M, Morton NE. A first trial of retrospective collaboration for positional cloning in complex inheritance: assay of the cytokine region on chromosome 5 by the consortium on asthma genetics (COAG). Proc Natl Acad Sci U S A 2000; 97:10942-7. [PMID: 11005866 PMCID: PMC27128 DOI: 10.1073/pnas.97.20.10942] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/03/2000] [Indexed: 01/22/2023] Open
Abstract
The central problem of complex inheritance is to map oligogenes for disease susceptibility, integrating linkage and association over samples that differ in several ways. Combination of evidence over multiple samples with 1,037 families supports loci contributing to asthma susceptibility in the cytokine region on 5q [maximum logarithm of odds (lod) = 2.61 near IL-4], but no evidence for atopy. The principal problems with retrospective collaboration on linkage appear to have been solved, providing far more information than a single study. A multipoint lod table evaluated at commonly agreed reference loci is required for both collaboration and metaanalysis, but variations in ascertainment, pedigree structure, phenotype definition, and marker selection are tolerated. These methods are invariant with statistical methods that increase the power of lods and are applicable to all diseases, motivating collaboration rather than competition. In contrast to linkage, positional cloning by allelic association has yet to be extended to multiple samples, a prerequisite for efficient combination with linkage and the greatest current challenge to genetic epidemiology.
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Affiliation(s)
- C Lonjou
- Human Genetics Research Division, University of Southampton, Southampton General Hospital, Southampton SO16 6YD, United Kingdom
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38
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Abstract
Altered beta-adrenergic regulation has been reported in individuals with hypertension. The variability in vascular responsiveness to beta-agonists, such as isoproterenol, observed in humans may be explained partially by beta(2)-adrenoceptor polymorphism. Individuals with the Gln27 form of the receptor may show reduced vascular reactivity because of downregulation expression of the receptor in the vasculature. We screened 127 normotensive white subjects, 37 of whom were homozygous for these alleles. Thirty-two subjects (17 Gln27 and 15 Glu27) agreed to receive brachial artery infusions of isoproterenol at doses of 1 to 300 ng. min(-1); forearm blood flow was measured by using venous occlusion plethysmography. Of these subjects, 25 (12 Glu27 and 13 Gln27) received local doses of isoproterenol (0.3 to 30.0 ng. min(-1)) via a dorsal hand vein preconstricted with norepinephrine. Compared with subjects homozygous for the Glu27 allele, subjects with the Gln27 substitution had lower baseline blood flow and, in response to isoproterenol, had a significantly attenuated increase in forearm blood flow. This pattern was more marked in veins. We also studied the relationship between the position 16 polymorphism and vascular reactivity. Homozygotes for Arg16 had significantly lower basal blood flow and attenuated increases in forearm blood flow compared with the Gly16 homozygotes. This was significant in veins but not in arteries. Thus, beta(2)-adrenoceptor genotype determines vascular responses to isoproterenol in forearm resistance vessels and in capacitance vessels. Further studies are necessary to establish whether beta(2)-adrenoceptor polymorphisms are important in the genesis of hypertension.
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Affiliation(s)
- J R Cockcroft
- School of Medical and Surgical Sciences, Division of Therapeutics, University of Nottingham Medical School, Queen's Medical Centre, Nottingham, UK.
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39
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Abstract
The airway smooth muscle cell is the chief effector cell governing the control of airway calibre in the human lung. The contractile state of the airway smooth muscle cell is predominantly influenced by the balance of constrictor and relaxant stimuli. Agents such as histamine and acetylcholine cause airway smooth muscle cells to contract through activation of specific cell surface receptors and engagement of signal transduction pathways and/or ion channels. The predominant pathway mediating constriction is activation of phospholipase C, with release of inositol 1,4,5-triphosphate and elevation of intracellular calcium levels. Relaxation is brought about predominantly by stimulation of adenylyl cyclase-coupled receptors (e.g. the beta2-adrenoceptor) resulting in elevation of cell cyclic adenosine monophosphate content. Complex crosstalk occurs between both of these pathways and also ion channels expressed on the airway smooth muscle cell membrane, leading to careful regulation of airway smooth muscle tone. A greater understanding of the mechanisms governing control of these pathways will lead to the identification of novel therapeutic targets which will in turn lead to new agents for the treatment of asthma.
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Affiliation(s)
- I P Hall
- Division of Therapeutics, University Hospital, Nottingham, UK
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Affiliation(s)
- I P Hall
- Division of Therapeutics, University Hospital, Nottingham, UK
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Affiliation(s)
- I P Hall
- Division of Therapeutics, University Hospital, Nottingham, UK
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Candy G, Samani N, Norton G, Woodiwiss A, Radevski I, Wheatley A, Cockcroft J, Hall IP. Association analysis of beta2 adrenoceptor polymorphisms with hypertension in a Black African population. J Hypertens 2000; 18:167-72. [PMID: 10694184 DOI: 10.1097/00004872-200018020-00006] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.8] [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: 11/25/2022]
Abstract
OBJECTIVE To determine whether or not beta2 adrenoceptor polymorphism is a risk factor for the development of hypertension in a Black South African population. BACKGROUND Attenuated vasodilator responses to endogenous catecholamines may contribute to the aetiology of hypertension. Downregulation of beta2 adrenoreceptors (beta2AR) following stimulation with agonists is determined in part by variation at the beta2AR gene locus. The Glu27 beta2AR genotype results in attenuated downregulation compared with the wild-type Gln27 receptor, whereas Gly16 exhibits enhanced down-regulation compared to Arg16. Possible racial differences in the prevalence of the beta2AR polymorphisms may be an explanation for the blunted responses to isoprenaline and the increased prevalence of hypertension in Black African populations. METHODS One hundred and ninety-two unrelated hypertensives and 123 normotensives of Black South African origin were studied. Hypertensives were recruited from hospital hypertension clinics in the province of Gauteng and if on treatment, had a 2-4 week washout period before 24-h ambulatory blood pressure assessment Normotensive controls were recruited from the same community. RESULTS There was no significant association between either the Arg-Gly16 polymorphism or the Gln-Glu27 polymorphism and hypertension status. Furthermore, in the hypertensives, no significant association was seen between beta2AR genotype at either site and clinical blood pressure, 24-h blood pressure or left ventricular mass. A significant association was seen between Arg16 homozygotes and lower body mass index in hypertensives (P = 0.007) although this was not a primary end point. Interestingly, the Glu27 polymorphism was much rarer in this population (allelic frequency 17%) compared to a Caucasian population. CONCLUSION These data suggest that beta2AR polymorphism is not a risk factor for hypertension per se in this defined population. The possibility that the decreased prevalence of Glu27 in black South African populations explains blunted vasodilator responses to isoprenaline requires further study.
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Affiliation(s)
- G Candy
- Department of Physiology and Medicine, University of the Witwatersrand, South Africa
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43
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Abstract
The interleukin-4 (IL-4) signalling cascade has been identified as a pathway potentially important in the development of asthma. Genetic variants within this signalling pathway might contribute to the risk of developing asthma in a given individual. A number of polymorphisms have been described within the IL-4 receptor alpha (IL-4Ralpha) gene. In addition polymorphism occurs in the promoter for the IL-4 gene itself. This commentary accompanies a paper by C Ober et al describing the contribution of IL-4Ralpha polymorphism to susceptibility to asthma and atopy in the Hutterite population and other outbred populations collected during the collaborative studies on the genetics of asthma (CSGA) programme.
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Affiliation(s)
- I P Hall
- Division of Therapeutics, University Hospital of Nottingham, Nottingham, UK.
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Billington CK, Hall IP, Mundell SJ, Parent JL, Panettieri RA, Benovic JL, Penn RB. Inflammatory and contractile agents sensitize specific adenylyl cyclase isoforms in human airway smooth muscle. Am J Respir Cell Mol Biol 1999; 21:597-606. [PMID: 10536119 DOI: 10.1165/ajrcmb.21.5.3759] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.9] [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: 11/24/2022] Open
Abstract
Beta-agonists, through activation of the beta(2)-adrenergic receptor (beta(2)AR)-G(s)-adenylyl cyclase (AC) pathway, promote bronchodilation via functional antagonism of airway smooth muscle (ASM) spasmogens associated with the asthmatic state. Although previous studies have demonstrated that beta(2)AR signaling in ASM is subject to homologous (beta-agonist-induced) beta(2)AR desensitization, the potential for inflammatory and contractile agents to impact beta(2)AR signaling in ASM through heterologous mechanisms has not been defined. Here we report that chronic exposure of human ASM (HASM) to carbachol, serotonin, the thromboxane analogue U46619, or histamine induced little change or a small increase in isoproterenol-stimulated cyclic adenosine monophosphate (cAMP) formation, but significantly increased cAMP formation elicited by stimulation with forskolin. This latter increase in intrinsic AC activity was largely reversed by pertussis toxin pretreatment, and was unaffected by protein kinase C inhibition. Analysis of both AC function and isoform expression supports a dominant role of AC VI in HASM, and points to important differences in ASM AC isoform expression among species. Additional studies identify AC as the limiting component in beta(2)AR-G(s)-AC signaling in HASM, and thus a potentially important target of therapeutic strategies designed to influence airway contractile state.
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Affiliation(s)
- C K Billington
- Department of Therapeutics, Institute of Cell Signalling, University Hospital of Nottingham, Nottingham, United Kingdom
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Abstract
We report that individuals carrying the CCR5 delta32 mutation, a naturally occurring variant of the C-C chemokine receptor 5 (CCR5), are at reduced risk of developing asthma. These data suggest a possible explanation for the high prevalence of this mutation in the general population.
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Lipworth BJ, Hall IP, Aziz I, Tan KS, Wheatley A. Beta2-adrenoceptor polymorphism and bronchoprotective sensitivity with regular short- and long-acting beta2-agonist therapy. Clin Sci (Lond) 1999; 96:253-9. [PMID: 10029561] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023]
Abstract
The aim of the present study was to investigate bronchoprotective sensitivity in patients receiving regular treatment with short- and long-acting beta2-agonists and to evaluate any possible association with genetic polymorphism. Thirty-eight patients with stable mild to moderate asthma and receiving inhaled corticosteroids were randomized in a parallel group, double-blind, double-dummy fashion to receive 2 weeks of treatment with either formoterol (12 microg once daily, 6 microg twice daily or 24 microg twice daily) or terbutaline (500 microg four times daily). Bronchoprotection against methacholine challenge (as a provocative dose to produce a 20% fall in forced expiratory volume in 1.0 s: PD20) was measured at baseline (unprotected) after an initial 1 week run-in without beta2-agonist, and at 1 h after the first and last doses of each treatment. The PD20 values were log-transformed and calculated as change from baseline. Percentage desensitization of log PD20 for first- versus last-dose bronchoprotection was calculated and analysed according to effects of treatment and beta2-adrenoceptor polymorphism at codon 16 or 27. The mean degree of desensitization for bronchoprotection was comparable with all four treatments and there were no significant differences in absolute PD20 values after 2 weeks of chronic dosing. The PD20 values were (as microg of methacholine, geometric means+/-S. E.M.): formoterol, 12 microg once daily, 99+/-42 microg; formoterol, 6 microg twice daily, 107+/-44 microg; formoterol, 24 microg twice daily, 108+/-45 microg; terbutaline, 500 microg four times daily, 88+/-37 microg. All patients receiving formoterol, 24 microg twice daily, exhibited a loss of protection greater than 30% which was unrelated to polymorphism at codon 16 or 27. For codon 16, the use of lower doses of formoterol (12 microg once daily or 6 microg twice daily) showed wider variability in the propensity for protection loss in patients who were heterozygous, in contrast to a more uniform protection loss seen with homozygous glycine patients. The amount of protection loss was not significantly related to polymorphism at codon 16 or 27, expressed as values (mean+/-S.E.M.) for percentage desensitization according to each genotype (pooled treatments): Gly-16, 66+/-11%; Het-16, 53+/-8%; Arg-16, 69+/-18%; Glu-27, 68+/-12%; Het-27, 58+/-8%; Gln-27, 52+/-12%. The results of this preliminary study showed that bronchoprotective desensitization occurred readily in response to short- or long-acting beta2-agonist exposure irrespective of beta2-adrenoceptor polymorphism at codon 16 or 27. Further studies with larger patient numbers are required to further evaluate the effects of polymorphisms with lower doses of regular formoterol.
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Affiliation(s)
- B J Lipworth
- Department of Clinical Pharmacology and Therapeutics, Ninewells Hospital and Medical School, University of Dundee, Dundee DD1 9SY, Scotland, U.K
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Billington CK, Joseph SK, Swan C, Scott MG, Jobson TM, Hall IP. Modulation of human airway smooth muscle proliferation by type 3 phosphodiesterase inhibition. Am J Physiol 1999; 276:L412-9. [PMID: 10070104 DOI: 10.1152/ajplung.1999.276.3.l412] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Elevation in cell cAMP content can inhibit mitogenic signaling in cultured human airway smooth muscle (HASM) cells. We studied the effects of the type 3-selective phosphodiesterase inhibitor siguazodan, the type 4-selective phosphodiesterase inhibitor rolipram, and the nonselective inhibitor 3-isobutyl-1-methylxanthine (IBMX) on proliferation of cultured HASM cells. At concentrations selective for the type 3 phosphodiesterase isoform, siguazodan inhibited both [3H]thymidine incorporation (IC50 2 microM) and the increase in cell number (10 microM; 64% reduction) induced by platelet-derived growth factor-BB (20 ng/ml). These effects were mimicked by IBMX. At concentrations selective for type 4 phosphodiesterase inhibition, rolipram was without effect. A 20-min exposure to siguazodan and rolipram did not increase whole cell cAMP levels. However, in HASM cells transfected with a cAMP-responsive luciferase reporter (p6CRE/Luc), increases in cAMP-driven luciferase expression were seen with siguazodan (3.9-fold) and IBMX (16.5-fold). These data suggest that inhibition of the type 3 phosphodiesterase isoform present in airway smooth muscle results in inhibition of mitogenic signaling, possibly through an increase in cAMP-driven gene expression.
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Affiliation(s)
- C K Billington
- Division of Therapeutics, University Hospital, Nottingham NG7 2UH, United Kingdom
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Lipworth BJ, Hall IP, Tan S, Aziz I, Coutie W. Effects of genetic polymorphism on ex vivo and in vivo function of beta2-adrenoceptors in asthmatic patients. Chest 1999; 115:324-8. [PMID: 10027427 DOI: 10.1378/chest.115.2.324] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.6] [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: 11/01/2022] Open
Abstract
BACKGROUND Genetic polymorphism determines agonist-induced down-regulation and desensitization of beta2-adrenoceptors. OBJECTIVES The aim of the present study was to investigate the effects of genetic polymorphism on ex vivo (lymphocytes) and in vivo (bronchoprotection) function of beta2-adrenoceptors in asthmatic patients, having been washed out of previous beta2-agonist exposure. METHODS Sixty patients with stable mild-to-moderate asthma were evaluated, with a post hoc analysis of genotype performed at end of study. Having withheld treatment with long-acting beta2-agonists for > or = 48 h and short-acting beta2-agonists for > or = 12 h, measurements of lymphocyte beta2-adrenoceptors were made for binding density, binding affinity, basal cyclic adenosine monophosphate (cAMP), and maximal cAMP response to isoproterenol (Emax). In addition, in 48 of these patients who were methacholine responsive (PD20 < 1,000 microg), the acute protective effect of formoterol as a 24-microg single dose (at 1 h) was also evaluated. Comparisons were made according to homozygous and heterozygous (Het) polymorphisms at codon 16 and codon 27. RESULTS There were no significant differences in age, FEV1 percent predicted, or inhaled corticosteroid dose, when comparing mean values for polymorphisms at either codon-16 or codon 27. There were also no significant differences between polymorphisms for any of the measured lymphocyte beta2-adrenoceptor parameters apart from basal cAMP between Glu-27 and Het-27. Mean values for Emax (after-before isoproterenol as pmol/10(6) cells) were as follows: Gly-16 (3.4), Arg-16 (3.5), Het-16 (4.0), Glu-27 (3.9), Gln-27 (3.5), and Het-27 (3.7). Polylorphism had no significant effect on formoterol protection as doubling dose shift in methacholine PD20 (geometric mean): Gly-16 (5.3), Arg-16 (5.4), Het-16 (4.6), Glu-27 (5.3), Gln-27 (5.3), Het-27 (4.5). CONCLUSIONS Our results show that genetic polymorphism at codon 16 or 27 does not influence stimulated coupling of lymphocyte beta2-adrenoceptors and similarly did not influence the degree of functional antagonism exhibited by formoterol. Thus, a single dose of beta2-agonist when used on demand affords equal protection against bronchoprotection regardless of genetic polymorphism.
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Affiliation(s)
- B J Lipworth
- Department of Clinical Pharmacology and Therapeutics, Ninewells Hospital and Medical School, University of Dundee, Scotland, UK.
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Abstract
The field of asthma genetics has evolved in a markedly short time into a research field which potentially can provide a new level of understanding on the pathophysiology of the disease. There is consensus over a number of candidate genes that are likely to be important in the disease and also in chromosomal regions likely to contain other novel genes. It is, however, clear that there is no single major genetic risk factor for the development of asthma and the development of the disease in an individual will depend upon the interaction of a number of genes of moderate effect with environmental factors.
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Affiliation(s)
- I P Hall
- Division of Therapeutics, University Hospital, Nottingham, UK
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