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Konjevod M, Sreter KB, Popovic-Grle S, Lampalo M, Tudor L, Jukic I, Nedic Erjavec G, Bingulac-Popovic J, Safic Stanic H, Nikolac Perkovic M, Markeljevic J, Samarzija M, Pivac N, Svob Strac D. Platelet Serotonin (5-HT) Concentration, Platelet Monoamine Oxidase B (MAO-B) Activity and HTR2A, HTR2C, and MAOB Gene Polymorphisms in Asthma. Biomolecules 2023; 13:biom13050800. [PMID: 37238670 DOI: 10.3390/biom13050800] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Revised: 05/05/2023] [Accepted: 05/06/2023] [Indexed: 05/28/2023] Open
Abstract
The complex role of the serotonin system in respiratory function and inflammatory diseases such as asthma is unclear. Our study investigated platelet serotonin (5-HT) levels and platelet monoamine oxidase B (MAO-B) activity, as well as associations with HTR2A (rs6314; rs6313), HTR2C (rs3813929; rs518147), and MAOB (rs1799836; rs6651806) gene polymorphisms in 120 healthy individuals and 120 asthma patients of different severity and phenotypes. Platelet 5-HT concentration was significantly lower, while platelet MAO-B activity was considerably higher in asthma patients; however, they did not differ between patients with different asthma severity or phenotypes. Only the healthy subjects, but not the asthma patients, carrying the MAOB rs1799836 TT genotype had significantly lower platelet MAO-B activity than the C allele carriers. No significant differences in the frequency of the genotypes, alleles, or haplotypes for any of the investigated HTR2A, HTR2C and MAOB gene polymorphisms have been observed between asthma patients and healthy subjects or between patients with various asthma phenotypes. However, the carriers of the HTR2C rs518147 CC genotype or C allele were significantly less frequent in severe asthma patients than in the G allele carriers. Further studies are necessary to elucidate the involvement of the serotonergic system in asthma pathophysiology.
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Affiliation(s)
- Marcela Konjevod
- Rudjer Boskovic Institute, Division of Molecular Medicine, Bijenicka Cesta 54, 10000 Zagreb, Croatia
| | - Katherina B Sreter
- Department of Clinical Immunology, Pulmonology and Rheumatology, University Hospital Centre "Sestre Milosrdnice", 10000 Zagreb, Croatia
| | - Sanja Popovic-Grle
- Clinic for Lung Diseases Jordanovac, University Hospital Centre Zagreb, 10000 Zagreb, Croatia
- School of Medicine, University of Zagreb, 10000 Zagreb, Croatia
| | - Marina Lampalo
- Clinic for Lung Diseases Jordanovac, University Hospital Centre Zagreb, 10000 Zagreb, Croatia
| | - Lucija Tudor
- Rudjer Boskovic Institute, Division of Molecular Medicine, Bijenicka Cesta 54, 10000 Zagreb, Croatia
| | - Irena Jukic
- Croatian Institute of Transfusion Medicine, 10000 Zagreb, Croatia
- Faculty of Medicine, Josip Juraj Strossmayer University of Osijek, 31000 Osijek, Croatia
| | - Gordana Nedic Erjavec
- Rudjer Boskovic Institute, Division of Molecular Medicine, Bijenicka Cesta 54, 10000 Zagreb, Croatia
| | | | | | - Matea Nikolac Perkovic
- Rudjer Boskovic Institute, Division of Molecular Medicine, Bijenicka Cesta 54, 10000 Zagreb, Croatia
| | - Jasenka Markeljevic
- Department of Clinical Immunology, Pulmonology and Rheumatology, University Hospital Centre "Sestre Milosrdnice", 10000 Zagreb, Croatia
- School of Medicine, University of Zagreb, 10000 Zagreb, Croatia
| | - Miroslav Samarzija
- Clinic for Lung Diseases Jordanovac, University Hospital Centre Zagreb, 10000 Zagreb, Croatia
- School of Medicine, University of Zagreb, 10000 Zagreb, Croatia
| | - Nela Pivac
- Rudjer Boskovic Institute, Division of Molecular Medicine, Bijenicka Cesta 54, 10000 Zagreb, Croatia
- University of Applied Sciences "Hrvatsko Zagorje Krapina", 49000 Krapina, Croatia
| | - Dubravka Svob Strac
- Rudjer Boskovic Institute, Division of Molecular Medicine, Bijenicka Cesta 54, 10000 Zagreb, Croatia
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Association of the 5HTR2C gene Ser23 variation with childhood allergic asthma. THE EUROBIOTECH JOURNAL 2022. [DOI: 10.2478/ebtj-2022-0013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Abstract
Objective: Allergic asthma is the most frequently observed subtype of individuals with asthma. The effects of serotonin plays in the pathophysiology of asthma has not been clearly determined. Thus, this study aimed to investigate the association between the 5HTR2C gene rs 6318 G>C polymorphism and allergic asthma in pediatric patients in Cyprus.
Methods: This study included total number of 177 individuals with 118 control and 59 pediatric patients (43 atopic and 16 non-atopic asthma patient). A skin prick test was performed for each patient to confirm asthma diagnosis and to evaluate atopic status. Genotyping for the 5HTR2C was completed by Real Time-PCR analysis.
Results: The genotype distribution frequencies were not in agreement with the Hardy-Weinberg Equilibrium in the patients’ group (p<0.00001). The frequency of the risk allele (allele C) was not significantly different between the patient and control groups (p=0.255). The genotypic distribution between atopic asthma and non-atopic asthma within the patientsts groups was not in agreement with the Hardy-Weinberg Equilibrium (p=0.006). However, risk allele presence showed a statistically significant association with atopy-related asthma (p=0.037).
Discussion & Conclusion: Overall, despite the finding of no association between the 5HTR2C rs6318 C allele and childhood asthma, the current results indicated that there is a strong association between the 5HTR2C rs6318 C variant and childhood atopic asthma.
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Tian M, Xia P, Yan L, Gou X, Giesy JP, Dai J, Yu H, Zhang X. Toxicological Mechanism of Individual Susceptibility to Formaldehyde-Induced Respiratory Effects. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:6511-6524. [PMID: 35438505 DOI: 10.1021/acs.est.1c07945] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Understanding the mechanisms of individual susceptibility to exposure to environmental pollutants has been a challenge in health risk assessment. Here, an integrated approach combining a CRISPR screen in human cells and epidemiological analysis was developed to identify the individual susceptibility to the adverse health effects of air pollutants by taking formaldehyde (FA) and the associated chronic obstructive pulmonary disease (COPD) as a case study. Among the primary hits of CRISPR screening of FA in human A549 cells, HTR4 was the only gene genetically associated with COPD susceptibility in global populations. However, the association between HTR4 and FA-induced respiratory toxicity is unknown in the literature. Adverse outcome pathway (AOP) network analysis of CRISPR screen hits provided a potential mechanistic link between activation of HTR4 (molecular initiating event) and FA-induced lung injury (adverse outcome). Systematic toxicology tests (in vitro and animal experiments) were conducted to reveal the HTR4-involved biological mechanisms underlying the susceptibility to adverse health effects of FA. Functionality and enhanced expression of HTR4 were required for susceptibility to FA-induced lung injury, and FA-induced epigenetic changes could result in enhanced expression of HTR4. Specific epigenetic and genetic characteristics of HTR4 were associated with the progression and prevalence of COPD, respectively, and these genetic risk factors for COPD could be potential biomarkers of individual susceptibility to adverse respiratory effects of FA. These biomarkers could be of great significance for defining subpopulations susceptible to exposure to FA and reducing uncertainty in the next-generation health risk assessment of air pollutants. Our study delineated a novel toxicological pathway mediated by HTR4 in FA-induced lung injury, which could provide a mechanistic understanding of the potential biomarkers of individual susceptibility to adverse respiratory effects of FA.
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Affiliation(s)
- Mingming Tian
- State Key Laboratory of Pollution Control & Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, People's Republic of China
| | - Pu Xia
- State Key Laboratory of Pollution Control & Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, People's Republic of China
| | - Lu Yan
- State Key Laboratory of Pollution Control & Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, People's Republic of China
| | - Xiao Gou
- State Key Laboratory of Pollution Control & Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, People's Republic of China
| | - John P Giesy
- Department of Veterinary Biomedical Sciences and Toxicology Centre, University of Saskatchewan Saskatoon, Saskatoon SK S7N 5B3, Canada
- Zoology Department, Center for Integrative Toxicology, Michigan State University, 1129 Farm Lane Road, East Lansing, Michigan 48824, United States
- Department of Environmental Science, Baylor University, Waco, Texas 76798, United States
| | - Jiayin Dai
- Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, People's Republic of China
| | - Hongxia Yu
- State Key Laboratory of Pollution Control & Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, People's Republic of China
| | - Xiaowei Zhang
- State Key Laboratory of Pollution Control & Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, People's Republic of China
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Sohn M. Overview and challenges of current genetic research on allergic diseases in Korean children. ALLERGY ASTHMA & RESPIRATORY DISEASE 2018. [DOI: 10.4168/aard.2018.6.s1.s77] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- Myunghyun Sohn
- Department of Pediatrics, Yonsei University College of Medicine, Seoul, Korea
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Swanson G, Miller S, Alyahyawi A, Wilson B, Saadatmand F, Lee C, Dunston G, Abbas M. Genetic polymorphisms in the serotonin receptor 7 (HTR7) gene are associated with cortisol levels in African American young adults. F1000Res 2017. [DOI: 10.12688/f1000research.10442.1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Introduction: Serotonin is a neurohormone involved in biological processes, such as behavior and immune function. Chronic psychosocial stressors may cause serotonin release resulting in immune system dysregulation, as evidenced by increased or far decreased levels of cortisol, a blood biomarker of stress and immune function. We hypothesize that genetic polymorphisms in the HTR7 gene are associated with both hypo- and hyper-cortisolism. Methods: The study population included 602 African American subjects between 18-34 years of age, living in Washington, D.C. Five single nucleotide polymorphisms (SNPs) in HTR7, rs2420367, rs12412496, rs2185706, rs7089533, and rs7093602 were genotyped by restriction fragment length polymorphism or the TaqMan assay. Statistical analysis, using the program SNPstat, was performed to determine their associations with cortisol measured in the study population. Results: While an increased risk of hypocortisolism was found to be associated with rs2420367, rs2185706, and rs7093602 in a gender specific manner, no genotypes could be associated with hypercortisolism. Inversely, a decreased risk of hypocortisolism was found with the haplotype CGGCC (p=0.033), which remained significant in males. When adjusting for gender, females associated with the haplotype AGACC. Hypercortisolism was also associated with a decreased risk for the haplotypes AAACC (p=0.042) and AAGTT (p=0.001). Discussion: Based on these results, genetic variation in the HTR7 gene may contribute to both stress and inflammation, and will provide a new glimpse into stress-related inflammation psychophysiology.
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House JS, Li H, DeGraff LM, Flake G, Zeldin DC, London SJ. Genetic variation in HTR4 and lung function: GWAS follow-up in mouse. FASEB J 2014; 29:323-35. [PMID: 25342126 DOI: 10.1096/fj.14-253898] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Human genome-wide association studies (GWASs) have identified numerous associations between single nucleotide polymorphisms (SNPs) and pulmonary function. Proving that there is a causal relationship between GWAS SNPs, many of which are noncoding and without known functional impact, and these traits has been elusive. Furthermore, noncoding GWAS-identified SNPs may exert trans-regulatory effects rather than impact the proximal gene. Noncoding variants in 5-hydroxytryptamine (serotonin) receptor 4 (HTR4) are associated with pulmonary function in human GWASs. To gain insight into whether this association is causal, we tested whether Htr4-null mice have altered pulmonary function. We found that HTR4-deficient mice have 12% higher baseline lung resistance and also increased methacholine-induced airway hyperresponsiveness (AHR) as measured by lung resistance (27%), tissue resistance (48%), and tissue elastance (30%). Furthermore, Htr4-null mice were more sensitive to serotonin-induced AHR. In models of exposure to bacterial lipopolysaccharide, bleomycin, and allergic airway inflammation induced by house dust mites, pulmonary function and cytokine profiles in Htr4-null mice differed little from their wild-type controls. The findings of altered baseline lung function and increased AHR in Htr4-null mice support a causal relationship between genetic variation in HTR4 and pulmonary function identified in human GWAS.
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Affiliation(s)
- John S House
- *Division of Intramural Research, National Institute of Environmental Health Sciences, U.S. National Institutes of Health, Research Triangle Park, North Carolina, USA; and Division of the National Toxicology Program, U.S. National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina, USA
| | - Huiling Li
- *Division of Intramural Research, National Institute of Environmental Health Sciences, U.S. National Institutes of Health, Research Triangle Park, North Carolina, USA; and Division of the National Toxicology Program, U.S. National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina, USA
| | - Laura M DeGraff
- *Division of Intramural Research, National Institute of Environmental Health Sciences, U.S. National Institutes of Health, Research Triangle Park, North Carolina, USA; and Division of the National Toxicology Program, U.S. National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina, USA
| | - Gordon Flake
- *Division of Intramural Research, National Institute of Environmental Health Sciences, U.S. National Institutes of Health, Research Triangle Park, North Carolina, USA; and Division of the National Toxicology Program, U.S. National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina, USA
| | - Darryl C Zeldin
- *Division of Intramural Research, National Institute of Environmental Health Sciences, U.S. National Institutes of Health, Research Triangle Park, North Carolina, USA; and Division of the National Toxicology Program, U.S. National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina, USA
| | - Stephanie J London
- *Division of Intramural Research, National Institute of Environmental Health Sciences, U.S. National Institutes of Health, Research Triangle Park, North Carolina, USA; and Division of the National Toxicology Program, U.S. National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina, USA
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Park TJ, Park JS, Cheong HS, Park BL, Kim LH, Heo JS, Kim YK, Kim KU, Uh ST, Lee HS, Na JO, Seo KH, Choi JS, Kim YH, Kim MS, Park CS, Shin HD. Genome-wide association study identifies ALLC polymorphisms correlated with FEV₁ change by corticosteroid. Clin Chim Acta 2014; 436:20-6. [PMID: 24792382 DOI: 10.1016/j.cca.2014.04.023] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2014] [Revised: 04/16/2014] [Accepted: 04/18/2014] [Indexed: 12/14/2022]
Abstract
OBJECTIVES Asthma can be suppressed by inhaled corticosteroids (ICS). However, response to ICS shows marked inter-individual variability. This study is aimed to identify the genetic variants associated with the change in the percentage of forced expiratory volume in 1second (%ΔFEV1) following ICS treatment. METHODS A genome-wide association study was performed in a Korean asthmatic cohort. To further investigate these genetic associations, 11 additional single-nucleotide polymorphisms (SNPs) on the allantoicase (ALLC) gene were selected from the HapMap database and genotyped in the same asthmatic patients in the follow-up study. RESULTS In a genome-wide study, we identified the lowest P-value in ALLC, but none of the SNPs met the genome-wide association criteria (P<1.0×10(-8)). However, among 25 SNPs on ALLC in the follow-up study, 6 variants showed significant associations with the mean %ΔFEV1 in the study subjects (P<3.73×10(-6)). CONCLUSIONS Although the associated signals could not overcome the genome-wide multiple correction due to small sample size (n=189), our results suggest that associated SNPs of ALLC might be genetic predictors of response to ICS, at least with respect to ΔFEV1 in Korean asthmatics.
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Affiliation(s)
- Tae-Joon Park
- Department of Life Science, Sogang University, 35, Baekbeom-ro, Mapo-gu, Seoul 121-742, Republic of Korea
| | - Jong-Sook Park
- Division of Allergy and Respiratory Medicine, Soonchunhyang University Bucheon Hospital, 1174, Jung-dong, Wonmi-gu, Gyeonggi-do 420-020, Republic of Korea
| | - Hyun Sub Cheong
- Department of Genetic Epidemiology, SNP Genetics, Inc., 35, Baekbeom-ro, Mapo-gu, Seoul 121-742, Republic of Korea
| | - Byung-Lae Park
- Department of Genetic Epidemiology, SNP Genetics, Inc., 35, Baekbeom-ro, Mapo-gu, Seoul 121-742, Republic of Korea
| | - Lyoung Hyo Kim
- Department of Genetic Epidemiology, SNP Genetics, Inc., 35, Baekbeom-ro, Mapo-gu, Seoul 121-742, Republic of Korea
| | - Jeong Seok Heo
- Division of Allergy and Respiratory Medicine, Soonchunhyang University Bucheon Hospital, 1174, Jung-dong, Wonmi-gu, Gyeonggi-do 420-020, Republic of Korea
| | - Yang Ki Kim
- Division of Allergy and Respiratory Medicine, Soonchunhyang University Seoul Hospital, 59, Daesagwan-ro, Yongsan-gu, Seoul 140-887, Republic of Korea
| | - Ki-Up Kim
- Division of Allergy and Respiratory Medicine, Soonchunhyang University Seoul Hospital, 59, Daesagwan-ro, Yongsan-gu, Seoul 140-887, Republic of Korea
| | - Soo-Taek Uh
- Division of Allergy and Respiratory Medicine, Soonchunhyang University Seoul Hospital, 59, Daesagwan-ro, Yongsan-gu, Seoul 140-887, Republic of Korea
| | - Ho Sung Lee
- Division of Allergy and Respiratory Medicine, Soonchunhyang University Cheonan Hospital, 23-20, Byeongmyeong-dong, Dongnam-gu, Cheonan, Chungcheongnam-do 330-721, Republic of Korea
| | - Joo-Ock Na
- Division of Allergy and Respiratory Medicine, Soonchunhyang University Cheonan Hospital, 23-20, Byeongmyeong-dong, Dongnam-gu, Cheonan, Chungcheongnam-do 330-721, Republic of Korea
| | - Ki-Hyun Seo
- Division of Allergy and Respiratory Medicine, Soonchunhyang University Cheonan Hospital, 23-20, Byeongmyeong-dong, Dongnam-gu, Cheonan, Chungcheongnam-do 330-721, Republic of Korea
| | - Jae-Sung Choi
- Division of Allergy and Respiratory Medicine, Soonchunhyang University Cheonan Hospital, 23-20, Byeongmyeong-dong, Dongnam-gu, Cheonan, Chungcheongnam-do 330-721, Republic of Korea
| | - Yong Hoon Kim
- Division of Allergy and Respiratory Medicine, Soonchunhyang University Cheonan Hospital, 23-20, Byeongmyeong-dong, Dongnam-gu, Cheonan, Chungcheongnam-do 330-721, Republic of Korea
| | - Myung-Sin Kim
- Division of Allergy and Respiratory Medicine, Soonchunhyang University Gumi Hospital, 250, Gongdan-dong, Gumi, Kyungsangbook-do 730-706, Republic of Korea
| | - Choon-Sik Park
- Division of Allergy and Respiratory Medicine, Soonchunhyang University Bucheon Hospital, 1174, Jung-dong, Wonmi-gu, Gyeonggi-do 420-020, Republic of Korea.
| | - Hyoung Doo Shin
- Department of Life Science, Sogang University, 35, Baekbeom-ro, Mapo-gu, Seoul 121-742, Republic of Korea; Department of Genetic Epidemiology, SNP Genetics, Inc., 35, Baekbeom-ro, Mapo-gu, Seoul 121-742, Republic of Korea.
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Farjadian S, Moghtaderi M, Fakhraei B, Nasiri M, Farjam M. Association between serotonin transporter gene polymorphisms and childhood asthma. J Asthma 2013; 50:1031-5. [PMID: 23947391 DOI: 10.3109/02770903.2013.834503] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
BACKGROUND Asthma is a common chronic inflammatory disease of the airways in which genetic factors play a major role in its pathogenesis. High serotonin serum levels in patients with asthma suggest that serotonin is involved in the pathophysiology of the disease. Serotonin clearance is mediated by the serotonin reuptake transporter, and functional polymorphisms in this gene lead to altered serotonin reuptake efficiency. OBJECTIVE The aim of this study was to investigate the relationship between serotonin transporter gene polymorphisms and asthma. METHODS Serotonin transporter gene polymorphisms (5-HTTLPR, rs35521 and STin2.VNTR) were assessed by PCR-based methods in 100 children with mild to moderate persistent asthma and compared with 100 healthy controls. RESULTS There were no significant differences in allele, genotype or haplotype frequencies between patients and controls. No association was observed between SERT gene polymorphisms after stratification of patients for sex, age, spirometry indices, family history, passive smoking behavior and concomitant allergic rhinitis. Significant differences were observed in the distribution of 5-HTTLPR alleles (p = 0.025) and genotypes (p = 0.021) between patients with and without atopic dermatitis. CONCLUSIONS Despite strong evidence suggesting the role of serotonin in the pathophysiology of asthma, we found no association between serotonin transporter gene polymorphisms and mild to moderate persistent asthma. Further serotonin transporter gene analyses in patients with severe asthma may open up new horizons in the utilization of common serotonin regulators to treat asthma, based on their pharmacogenetic effects. However, serotonin may also be indirectly influenced by emotional stress during asthma attacks.
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Hodge E, Nelson CP, Miller S, Billington CK, Stewart CE, Swan C, Malarstig A, Henry AP, Gowland C, Melén E, Hall IP, Sayers I. HTR4 gene structure and altered expression in the developing lung. Respir Res 2013; 14:77. [PMID: 23890215 PMCID: PMC3750317 DOI: 10.1186/1465-9921-14-77] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2013] [Accepted: 07/23/2013] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Meta-analyses of genome-wide association studies (GWAS) have identified single nucleotide polymorphisms (SNPs) spanning the 5-hydroxytryptamine receptor 4 (5-HT₄R) gene (HTR4) associated with lung function. The aims of this study were to i) investigate the expression profile of HTR4 in adult and fetal lung tissue and cultured airway cells, ii) further define HTR4 gene structure and iii) explore the potential functional implications of key SNPs using a bioinformatic approach. METHODS Following reverse transcription (RT)-PCR in human brain, 5' rapid amplification of cDNA ends (5' RACE) was used to examine the exonic structure of HTR4 at the 5' end. Quantitative (Q)-PCR was used to quantify HTR4 mRNA expression in total RNA from cultured airway cells and whole lung tissue. Publically available gene microarray data on fetal samples of estimated gestational age 7-22 weeks were mined for HTR4 expression. Immunohistochemistry (IHC; in adult and fetal lung tissue) and a radioligand binding assay (in cultured airway cells) were used to analyze 5-HT₄R protein expression. RESULTS IHC in adult lung, irrespective of the presence of chronic obstructive pulmonary disease (COPD), suggested low level expression of 5-HT₄R protein, which was most prominent in alveolar pneumocytes. There was evidence of differential 5-HT₄R protein levels during gestation in fetal lung, which was also evident in gene expression microarray data. HTR4 mRNA expression, assessed by Q-PCR, was <0.5% relative to brain in total adult lung tissue and in human airway smooth muscle (HASM) and bronchial epithelial cells (HBEC) derived from adult donors. Radioligand binding experiments also indicated that HBEC and HASM cells did not express a significant 5-HT₄R population. 5' RACE in brain identified a novel N-terminal variant, containing an extended N-terminal sequence. The functional significance of key HTR4 SNPs was investigated using the encyclopedia of DNA elements consortium (ENCODE) dataset. These analyses identified multiple alterations in regulatory motifs for transcription factors implicated in lung development, including Foxp1. CONCLUSIONS Taken together, these data suggest a role for HTR4 in lung development, which may at least in part explain the genetic association with lung function.
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Affiliation(s)
- Emily Hodge
- Division of Respiratory Medicine, University of Nottingham, Queen’s Medical Centre, Nottingham NG7 2UH, UK
| | - Carl P Nelson
- Division of Respiratory Medicine, University of Nottingham, Queen’s Medical Centre, Nottingham NG7 2UH, UK
| | - Suzanne Miller
- Division of Respiratory Medicine, University of Nottingham, Queen’s Medical Centre, Nottingham NG7 2UH, UK
| | - Charlotte K Billington
- Division of Respiratory Medicine, University of Nottingham, Queen’s Medical Centre, Nottingham NG7 2UH, UK
| | - Ceri E Stewart
- Division of Respiratory Medicine, University of Nottingham, Queen’s Medical Centre, Nottingham NG7 2UH, UK
| | - Caroline Swan
- Division of Respiratory Medicine, University of Nottingham, Queen’s Medical Centre, Nottingham NG7 2UH, UK
| | - Anders Malarstig
- Precision Medicine Unit, Pfizer Global Research and Development, Cambridge, UK
| | - Amanda P Henry
- Division of Respiratory Medicine, University of Nottingham, Queen’s Medical Centre, Nottingham NG7 2UH, UK
| | - Catherine Gowland
- Division of Respiratory Medicine, University of Nottingham, Queen’s Medical Centre, Nottingham NG7 2UH, UK
| | - Erik Melén
- Institute of Environmental Medicine, Karolinska Institutet and Sachs’ Children’s Hospital, Stockholm, Sweden
| | - Ian P Hall
- Division of Respiratory Medicine, University of Nottingham, Queen’s Medical Centre, Nottingham NG7 2UH, UK
| | - Ian Sayers
- Division of Respiratory Medicine, University of Nottingham, Queen’s Medical Centre, Nottingham NG7 2UH, UK
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Knight DA, Yang IA, Ko FWS, Lim TK. Year in review 2011: asthma, chronic obstructive pulmonary disease and airway biology. Respirology 2012; 17:563-72. [PMID: 22248232 DOI: 10.1111/j.1440-1843.2012.02126.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Darryl A Knight
- UBC James Hogg Research Centre, Institute for Heart + Lung Health, Department of Anesthesiology, Pharmacology and Therapeutics, University of British Columbia, Vancouver, Canada.
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