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Xu F, Zhao L, Zhuang J, Gao X. Peripheral Neuroplasticity of Respiratory Chemoreflexes, Induced by Prenatal Nicotinic Exposure: Implication for SIDS. Respir Physiol Neurobiol 2023; 313:104053. [PMID: 37019251 DOI: 10.1016/j.resp.2023.104053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Revised: 03/23/2023] [Accepted: 04/02/2023] [Indexed: 04/05/2023]
Abstract
Sudden Infant Death Syndrome (SIDS) occurs during sleep in seemingly healthy infants. Maternal cigarette smoking and hypoxemia during sleep are assumed to be the major causal factors. Depressed hypoxic ventilatory response (dHVR) is observed in infants with high risk of SIDS, and apneas (lethal ventilatory arrest) appear during the fatal episode of SIDS. Disturbance of the respiratory center has been proposed to be involved, but the pathogenesis of SIDS is still not fully understood. Peripherally, the carotid body is critical to generate HVR, and bronchopulmonary and superior laryngeal C-fibers (PCFs and SLCFs) are important for triggering central apneas; however, their roles in the pathogenesis of SIDS have not been explored until recently. There are three lines of recently accumulated evidence to show the disorders of peripheral sensory afferent-mediated respiratory chemoreflexes in rat pups with prenatal nicotinic exposure (a SIDS model) in which acute severe hypoxia leads to dHVR followed by lethal apneas. (1) The carotid body-mediated HVR is suppressed with a reduction of the number and sensitivity of glomus cells. (2) PCF-mediated apneic response is largely prolonged via increased PCF density, pulmonary IL-1β and serotonin (5-hydroxytryptamine, 5-HT) release, along with the enhanced expression of TRPV1, NK1R, IL1RI and 5-HT3R in pulmonary C-neurons to strengthen these neural responses to capsaicin, a selective stimulant to C-fibers. (3) SLCF-mediated apnea and capsaicin-induced currents in superior laryngeal C-neurons are augmented by upregulation of TRPV1 expression in these neurons. These results, along with hypoxic sensitization/stimulation of PCFs, gain insight into the mechanisms of prenatal nicotinic exposure-induced peripheral neuroplasticity responsible for dHVR and long-lasting apnea during hypoxia in rat pups. Therefore, in addition to the disturbance in the respiratory center, the disorders of peripheral sensory afferent-mediated chemoreflexes may also be involved in respiratory failure and death denoted in SIDS victims.
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Farooq S, Khatri S. Life Course of Asthma. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2023; 1426:43-76. [PMID: 37464116 DOI: 10.1007/978-3-031-32259-4_3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/20/2023]
Abstract
Asthma is a heterogeneous chronic airway disease that can vary over a lifetime. Although broad categories of asthma by severity and type have been constructed, there remains a tremendous opportunity to discover an approach to managing asthma with additional factors in mind. Many in the field have suggested and are pursuing a novel paradigm shift in how asthma might be better managed, considering the life course of exposures, management priorities, and predicted trajectory of lung function growth. This approach will require a more holistic view of prenatal, postnatal, adolescence, hormonal and gender aspects, and the aging process. In addition, the environment, externally and internally, including in one's genetic code and epigenetic changes, are factors that affect how asthma progresses or becomes more stable in individuals. This chapter focuses on the various influences that may, to differing degrees, affect people with asthma, which can develop at any time in their lives. Shifting the paradigm of thought and strategies for care and advocating for public policies and health delivery that focus on this philosophy is paramount to advance asthma care for all.
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Affiliation(s)
- Sobia Farooq
- National Heart, Lung, and Blood Institute, CMO Division of Lung Diseases, Bethesda, MD, USA
| | - Sumita Khatri
- National Heart, Lung, and Blood Institute, CMO Division of Lung Diseases, Bethesda, MD, USA.
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3
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Yang D, Kim JW, Jeong H, Kim MS, Lim CW, Lee K, Kim B. Effects of maternal cigarette smoke exposure on the progression of nonalcoholic steatohepatitis in offspring mice. Toxicol Res 2023; 39:91-103. [PMID: 36726830 PMCID: PMC9839905 DOI: 10.1007/s43188-022-00153-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 08/01/2022] [Accepted: 08/22/2022] [Indexed: 02/04/2023] Open
Abstract
Cigarette smoke (CS) is a dominant carcinogenic agent in a variety of human cancers. CS exposure during pregnancy can adversely affect the fetus. Non-alcoholic fatty liver disease (NAFLD) is considered as a hepatic manifestation of a metabolic disorder, and ranges from simple steatosis to cirrhosis leading to hepatocellular carcinoma. Non-alcoholic steatohepatitis (NASH) is a more severe phase of NAFLD. Recently, there is increasing apprehension about the CS-related chronic liver diseases. Therefore, we examined whether maternal CS exposure could affect the pathogenesis of NASH in offspring. Mainstream CS (MSCS) was exposed to pregnant C57BL/6 mice via nose-only inhalation for 2 h/day, 5 days/week for 2 weeks from day 6 to 17 of gestation at 0, 300, or 600 μg/L. Three-week-old male offspring mice were fed methionine and choline-supplemented (MCS) diet or methionine and choline-deficient including high-fat (MCDHF) diet for 6 weeks to induce NASH. Maternal MSCS exposure increased the severity of NASH by increasing serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels, hepatic total cholesterol (TC) and triglyceride (TG) levels, pro-inflammation, fibrosis, and steatosis in offspring mice. Especially, maternal MSCS exposure significantly downregulated the phosphorylation of AMP-activated protein kinase (AMPK) in MCDHF diet-fed offspring mice. Subsequently, the protein levels of sterol regulatory element-binding protein (SREBP)-1c and stearoyl-CoA desaturase-1 (SCD1) were upregulated by maternal MSCS exposure. In conclusion, maternal MSCS exposure exacerbates the progression of NASH by modulating lipogenesis on offspring mice. Supplementary Information The online version contains supplementary material available at 10.1007/s43188-022-00153-1.
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Affiliation(s)
- Daram Yang
- Biosafety Research Institute and Laboratory of Veterinary Pathology, College of Veterinary Medicine, Jeonbuk National University, 79 Gobong-Ro, Iksan-Si, Jeollabuk-Do 54596 Republic of Korea
| | - Jong Won Kim
- Biosafety Research Institute and Laboratory of Veterinary Pathology, College of Veterinary Medicine, Jeonbuk National University, 79 Gobong-Ro, Iksan-Si, Jeollabuk-Do 54596 Republic of Korea
| | - Hyuneui Jeong
- Biosafety Research Institute and Laboratory of Veterinary Pathology, College of Veterinary Medicine, Jeonbuk National University, 79 Gobong-Ro, Iksan-Si, Jeollabuk-Do 54596 Republic of Korea
| | - Min Seok Kim
- Inhalation Toxicology Center, Jeonbuk Department of Inhalation Research, Korea Institute of Toxicology, 30, Baekak 1-Gil, Jeongeup, 56212 Republic of Korea
| | - Chae Woong Lim
- Biosafety Research Institute and Laboratory of Veterinary Pathology, College of Veterinary Medicine, Jeonbuk National University, 79 Gobong-Ro, Iksan-Si, Jeollabuk-Do 54596 Republic of Korea
| | - Kyuhong Lee
- Inhalation Toxicology Center, Jeonbuk Department of Inhalation Research, Korea Institute of Toxicology, 30, Baekak 1-Gil, Jeongeup, 56212 Republic of Korea
| | - Bumseok Kim
- Biosafety Research Institute and Laboratory of Veterinary Pathology, College of Veterinary Medicine, Jeonbuk National University, 79 Gobong-Ro, Iksan-Si, Jeollabuk-Do 54596 Republic of Korea
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Shapiro CO, Proskocil BJ, Oppegard LJ, Blum ED, Kappel NL, Chang CH, Fryer AD, Jacoby DB, Costello RW, Drake MG. Airway Sensory Nerve Density Is Increased in Chronic Cough. Am J Respir Crit Care Med 2021; 203:348-355. [PMID: 32809840 DOI: 10.1164/rccm.201912-2347oc] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Rationale: Chronic cough is characterized by frequent urges to cough and a heightened sensitivity to inhaled irritants. Airway sensory nerves trigger cough. We hypothesized that sensory nerve density is increased in chronic cough, which may contribute to excessive and persistent coughing.Objectives: To measure airway nerve density (axonal length) and complexity (nerve branching, neuropeptide expression) in humans with and without chronic cough.Methods: Bronchoscopic human airway biopsies were immunolabeled for nerves and the sensory neuropeptide substance P. Eosinophil peroxidase was also quantified given previous reports showing associations between eosinophils and nerve density. Three-dimensional image z-stacks of epithelium and subepithelium were generated using confocal microscopy, and from these z-stacks, total nerve length, the number of nerve branch points, substance P expression, and eosinophil peroxidase were quantified within each airway compartment.Measurements and Main Results: Nerve length and the number of branch points were significantly increased in epithelium, but not subepithelium, in chronic cough compared with healthy airways. Substance P expression was scarce and was similar in chronic cough and healthy airways. Nerve length and branching were not associated with eosinophil peroxidase nor with demographics such as age and sex in either group.Conclusions: Airway epithelial sensory nerve density is increased in chronic cough, suggesting sensory neuroplasticity contributes to cough hypersensitivity.
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Affiliation(s)
- Clare O Shapiro
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Oregon Health & Science University, Portland, Oregon; and
| | - Becky J Proskocil
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Oregon Health & Science University, Portland, Oregon; and
| | - Laura J Oppegard
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Oregon Health & Science University, Portland, Oregon; and
| | - Emily D Blum
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Oregon Health & Science University, Portland, Oregon; and
| | - Nicole L Kappel
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Oregon Health & Science University, Portland, Oregon; and
| | - Christopher H Chang
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Oregon Health & Science University, Portland, Oregon; and
| | - Allison D Fryer
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Oregon Health & Science University, Portland, Oregon; and
| | - David B Jacoby
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Oregon Health & Science University, Portland, Oregon; and
| | - Richard W Costello
- Department of Medicine, Royal College of Surgeons in Ireland, Dublin, Ireland
| | - Matthew G Drake
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Oregon Health & Science University, Portland, Oregon; and
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5
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Wang Z, Wang L, Zhong F, Wu C, Hou ST. Early postnatal tobacco smoke exposure aggravates experimental autoimmune encephalomyelitis in adult rats. Neurochem Int 2020; 141:104892. [PMID: 33127393 DOI: 10.1016/j.neuint.2020.104892] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2020] [Revised: 10/13/2020] [Accepted: 10/23/2020] [Indexed: 12/20/2022]
Abstract
Although substantial evidence supports smoking as a risk factor for the development of multiple sclerosis (MS) in adulthood, it remains controversial whether early-life exposure to environmental tobacco smoke (ETS) increases the risk of MS later in life. Here, using experimental autoimmune encephalomyelitis (EAE) as an animal model for MS, we show that exposing neonatal rats during the first week (ETS1-EAE), but not the second week (ETS2-EAE) and the third week (ETS3-EAE) after birth, increased the severity of EAE in adulthood in comparison to pups exposed to filtered compressed air (AIR-EAE). The ETS1-EAE rats showed a worse neurological deficit score and a significant increase in CD4+ cell infiltration, demyelination, and axonal injury in the spinal cord compared to AIR-EAE, ETS2-EAE, and ETS3-EAE groups. Flow cytometry analysis showed that the ETS1 group had decreased numbers of regulatory T (Treg) cells and increased effector T (Teff) cells in the brain and spinal cord. The expressions of Treg upstream regulator Foxp3 and downstream cytokines such as IL-10 were also altered accordingly. Together, these findings demonstrate that neonatal ETS exposure suppresses Treg functions and aggravates the severity of EAE, confirming early-life exposure to ETS as a potential risk factor for multiple sclerosis in adulthood.
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Affiliation(s)
- Zhaowei Wang
- Department of Neurology, Shaoxing People's Hospital (Shaoxing Hospital, Zhejiang University School of Medicine), 568 Zhonxin Bei Road, Shaoxing City, Zhejiang Province, 312000, PR China
| | - Liping Wang
- Department of Neurology, Shaoxing People's Hospital (Shaoxing Hospital, Zhejiang University School of Medicine), 568 Zhonxin Bei Road, Shaoxing City, Zhejiang Province, 312000, PR China
| | - Fangfang Zhong
- Department of Neurology, Shaoxing People's Hospital (Shaoxing Hospital, Zhejiang University School of Medicine), 568 Zhonxin Bei Road, Shaoxing City, Zhejiang Province, 312000, PR China
| | - Chenglong Wu
- Department of Neurology, Shaoxing People's Hospital (Shaoxing Hospital, Zhejiang University School of Medicine), 568 Zhonxin Bei Road, Shaoxing City, Zhejiang Province, 312000, PR China
| | - Sheng-Tao Hou
- Brain Research Centre and Department of Biology, Southern University of Science and Technology, 1088 Xueyuan Blvd, Nanshan District, Shenzhen, Guangdong Province, 518055, PR China; Department of Biochemistry, Microbiology, and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada.
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Barrios J, Kho AT, Aven L, Mitchel JA, Park JA, Randell SH, Miller LA, Tantisira KG, Ai X. Pulmonary Neuroendocrine Cells Secrete γ-Aminobutyric Acid to Induce Goblet Cell Hyperplasia in Primate Models. Am J Respir Cell Mol Biol 2020; 60:687-694. [PMID: 30571139 DOI: 10.1165/rcmb.2018-0179oc] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Mucus overproduction is a major contributor to morbidity and mortality in asthma. Mucus overproduction is induced by orchestrated actions of multiple factors that include inflammatory cytokines and γ-aminobutyric acid (GABA). GABA is produced only by pulmonary neuroendocrine cells (PNECs) in the mouse lung. Recent studies in a neonatal mouse model of allergic inflammation have shown that PNECs play an essential role in mucus overproduction by GABA hypersecretion. Whether PNECs mediate dysregulated GABA signaling for mucus overproduction in asthma is unknown. In this study, we characterized the cellular source of GABA in the lungs of nonhuman primates and humans and assessed GABA secretion and signaling in primate disease models. We found that like in mice, PNECs were the major source of GABA in primate lungs. In addition, an infant nonhuman primate model of asthma exhibited an increase in GABA secretion. Furthermore, subjects with asthma had elevated levels of expression of a subset of GABA type α (GABAα) and type β (GABAβ) receptors in airway epithelium compared with those of healthy control subjects. Last, employing a normal human bronchial epithelial cell model of preinduced mucus overproduction, we showed pharmaceutical blockade of GABAα and GABAβ receptor signaling reversed the effect of IL-13 on MUC5AC gene expression and goblet cell proliferation. Together, our data demonstrate an evolutionarily conserved intraepithelial GABA signaling that, in concert with IL-13, plays an essential role in mucus overproduction. Our findings may offer new strategies to ameliorate mucus overproduction in patients with asthma by targeting PNEC secretion and GABA signaling.
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Affiliation(s)
- Juliana Barrios
- 1 The Pulmonary Center, Department of Medicine, Boston University School of Medicine, Boston, Massachusetts
| | - Alvin T Kho
- 2 The Channing Division of Network Medicine, and
| | - Linh Aven
- 1 The Pulmonary Center, Department of Medicine, Boston University School of Medicine, Boston, Massachusetts
| | - Jennifer A Mitchel
- 3 Department of Environmental Health, Harvard T. H. Chan School of Public Health, Boston, Massachusetts
| | - Jin-Ah Park
- 3 Department of Environmental Health, Harvard T. H. Chan School of Public Health, Boston, Massachusetts
| | - Scott H Randell
- 4 Department of Cell Biology and Physiology, School of Medicine, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina; and
| | - Lisa A Miller
- 5 Department of Anatomy, Physiology, and Cell Biology, School of Veterinary Medicine, University of California, Davis, California
| | | | - Xingbin Ai
- 6 Division of Pulmonary and Critical Care Medicine, Brigham and Women's Hospital, Boston, Massachusetts
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Hammer B, Wagner C, Divac Rankov A, Reuter S, Bartel S, Hylkema MN, Krüger A, Svanes C, Krauss-Etschmann S. In utero exposure to cigarette smoke and effects across generations: A conference of animals on asthma. Clin Exp Allergy 2019; 48:1378-1390. [PMID: 30244507 DOI: 10.1111/cea.13283] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Revised: 07/24/2018] [Accepted: 09/01/2018] [Indexed: 12/15/2022]
Abstract
BACKGROUND The prevalence of asthma and chronic obstructive pulmonary disease (COPD) has risen markedly over the last decades and is reaching epidemic proportions. However, underlying molecular mechanisms are not fully understood, hampering the urgently needed development of approaches to prevent these diseases. It is well established from epidemiological studies that prenatal exposure to cigarette smoke is one of the main risk factors for aberrant lung function development or reduced fetal growth, but also for the development of asthma and possibly COPD later in life. Of note, recent evidence suggests that the disease risk can be transferred across generations, that is, from grandparents to their grandchildren. While initial studies in mouse models on in utero smoke exposure have provided important mechanistic insights, there are still knowledge gaps that need to be filled. OBJECTIVE Thus, in this review, we summarize current knowledge on this topic derived from mouse models, while also introducing two other relevant animal models: the fruit fly Drosophila melanogaster and the zebrafish Danio rerio. METHODS This review is based on an intensive review of PubMed-listed transgenerational animal studies from 1902 to 2018 and focuses in detail on selected literature due to space limitations. RESULTS This review gives a comprehensive overview of mechanistic insights obtained in studies with the three species, while highlighting the remaining knowledge gaps. We will further discuss potential (dis)advantages of all three animal models. CONCLUSION/CLINICAL RELEVANCE Many studies have already addressed transgenerational inheritance of disease risk in mouse, zebrafish or fly models. We here propose a novel strategy for how these three model organisms can be synergistically combined to achieve a more detailed understanding of in utero cigarette smoke-induced transgenerational inheritance of disease risk.
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Affiliation(s)
- Barbara Hammer
- Early Life Origins of Chronic Lung Diseases, Research Center Borstel, Leibniz Lung Center, German Center for Lung Research (DZL), Borstel, Germany
| | - Christina Wagner
- Invertebrate Models, Research Center Borstel, Leibniz Lung Center, Borstel, Germany
| | - Aleksandra Divac Rankov
- Institute of Molecular Genetics and Genetic Engineering, University of Belgrade, Belgrade, Serbia
| | - Sebastian Reuter
- Department of Pulmonary Medicine, University Hospital Essen - Ruhrlandklinik, Essen, Germany
| | - Sabine Bartel
- Early Life Origins of Chronic Lung Diseases, Research Center Borstel, Leibniz Lung Center, German Center for Lung Research (DZL), Borstel, Germany
| | - Machteld N Hylkema
- GRIAC Research Institute, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.,Department of Pathology and Medical Biology, University Medical Center Groningen, Groningen, The Netherlands
| | - Arne Krüger
- Early Life Origins of Chronic Lung Diseases, Research Center Borstel, Leibniz Lung Center, German Center for Lung Research (DZL), Borstel, Germany.,Institute for Life Science and Technology, Hanze University of Applied Sciences, Groningen, The Netherlands
| | - Cecilie Svanes
- Centre for International Health, University of Bergen, Bergen, Norway.,Department of Occupational Medicine, Haukeland University Hospital, Bergen, Norway
| | - Susanne Krauss-Etschmann
- Early Life Origins of Chronic Lung Diseases, Research Center Borstel, Leibniz Lung Center, German Center for Lung Research (DZL), Borstel, Germany.,Institute for Experimental Medicine, Christian-Albrechts-Universitaet zu Kiel, Kiel, Germany
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8
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Neophytou AM, Oh SS, Hu D, Huntsman S, Eng C, Rodríguez-Santana JR, Kumar R, Balmes JR, Eisen EA, Burchard EG. In utero tobacco smoke exposure, DNA methylation, and asthma in Latino children. Environ Epidemiol 2019; 3:e048. [PMID: 31342008 PMCID: PMC6571182 DOI: 10.1097/ee9.0000000000000048] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Accepted: 03/26/2019] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND Maternal smoking during pregnancy is a risk factor for chronic disease later in life and has been associated with variability of DNA methylation at specific cytosine-phosphate-guanine (CpG) loci. We assessed the role of DNA methylation as a potential mediator of adverse effects of in utero tobacco smoke exposures on asthma outcomes in Latino children from the US mainland and Puerto Rico. METHODS Relationships between self-reported exposure and DNA methylation at CpG loci previously reported to be associated with maternal smoking were assessed in a subsample consisting of 572 children aged 8-21 years (310 cases with asthma, 262 healthy controls), sampled from a larger asthma case-control study. Subsequently, we assessed associations between top loci and asthma-related outcomes, followed by mediation analysis for loci for which associations with outcomes were observed. RESULTS Self-reported maternal smoking was associated with a -1.5% (95% confidence interval (CI) = -2.4%, -0.6%) lower methylation at CpG locus cg05575921 on the AHRR gene; a 1% increase in DNA methylation at the same locus resulted in an odds ratio (OR) of 0.90 (95% CI = 0.83, 0.96) for the odds of asthma. The OR for the indirect effect of maternal smoking on asthma mediated through methylation at the cg05575921 locus was 1.18 (95% CI = 1.07, 1.68), compared to the OR for the total effect of exposure in the parent study of 1.48 (95% CI = 1.03, 2.11). CONCLUSIONS Our findings suggest potential mediation by DNA methylation in the association between maternal smoking during pregnancy and asthma status.
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Affiliation(s)
- Andreas M. Neophytou
- Division of Environmental Health Sciences, School of Public Health, University of California, Berkeley, California
- Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, Colorado
| | - Sam S. Oh
- Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, Colorado
| | - Donglei Hu
- Department of Medicine, University of California, San Francisco, California
| | - Scott Huntsman
- Department of Medicine, University of California, San Francisco, California
| | - Celeste Eng
- Department of Medicine, University of California, San Francisco, California
| | | | - Rajesh Kumar
- Division of Allergy and Immunology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
- Ann & Robert H. Lurie Children’s Hospital of Chicago, Chicago, Illinois
| | - John R. Balmes
- Division of Environmental Health Sciences, School of Public Health, University of California, Berkeley, California
- Department of Medicine, University of California, San Francisco, California
| | - Ellen A. Eisen
- Division of Environmental Health Sciences, School of Public Health, University of California, Berkeley, California
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Abstract
Cough is a physiological defense reflex for protecting the airways from aspiration and irritation. Thus, roles of environmental triggers are postulated in the pathogenesis of chronic cough. There are several lines of epidemiological evidence demonstrating the relationships between environmental irritant and pollutant exposure and chronic cough. However, positive findings from cross-sectional studies just reflect the protective nature of cough but may not properly address the true impact of environmental triggers. If harmful inhalation is repeated, cough may be seen as chronic but indeed is protective in nature. Therefore, long-term residual outcomes would be the key for understanding the effects of environmental triggers on chronic cough. The present review aims to summarize the associations between chronic cough and environmental pollutants or irritant exposure, with a focus on the long-term residual effects of (1) chronic persistent exposure and (2) acute high-intensity exposure on chronic cough, and also to examine (3) whether childhood irritant/pollutant exposure may increase the risk of chronic cough in adulthood.
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Affiliation(s)
- Eun-Jung Jo
- Department of Internal Medicine, Pusan National University Hospital, Busan, Korea
| | - Woo-Jung Song
- Airway Sensation and Cough Research Laboratory, Department of Allergy and Clinical Immunology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
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10
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Chen L, He X, Xie Y, Huang Y, Wolff DW, Abel PW, Tu Y. Up-regulated miR-133a orchestrates epithelial-mesenchymal transition of airway epithelial cells. Sci Rep 2018; 8:15543. [PMID: 30341388 PMCID: PMC6195555 DOI: 10.1038/s41598-018-33913-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Accepted: 10/08/2018] [Indexed: 12/11/2022] Open
Abstract
Dysregulation of microRNAs (miRNAs) contributes to epithelial-mesenchymal transition (EMT) of cancer, but the pathological roles of miRNAs in airway EMT of lung diseases remains largely unknown. We performed sequencing and real-time PCR analysis of the miRNA expression profile of human airway epithelial cells undergoing EMT, and revealed miR-133a to be one of the most common up-regulated miRNAs. MiR-133a was previously reported to be persistently up-regulated in airway epithelial cells of smokers. We found that mice exposed to cigarette smoke (CS) showed airway hyper-responsiveness, a typical symptom occurring in CS-related lung diseases, up-regulation of miR-133a and EMT marker protein N-cadherin in airway epithelium. Importantly, miR-133a overexpression induces airway epithelial cells to undergo spontaneous EMT via down-regulation of grainyhead-like 2 (GRHL2), an epithelial specific transcriptional factor. Loss of GRHL2 causes down-regulation of epithelial splicing regulatory protein 1 (ESRP1), a central coordinator of alternative splicing processes that are critical in the regulation of EMT. Down-regulation of ESRP1 induces isoform switching of adherens junction-associated protein p120-catenin, and leads to the loss of E-cadherin. Our study is the first to demonstrate that up-regulated miR-133a orchestrates airway EMT via alternative splicing processes, which points to novel therapeutic possibilities for the treatment of CS-related lung disease.
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Affiliation(s)
- Linjie Chen
- Department of Pharmacology, Creighton University School of Medicine, Omaha, NE, USA
| | - Xiaobai He
- College of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang, Jiangsu, China
| | - Yan Xie
- Department of Pharmacology, Creighton University School of Medicine, Omaha, NE, USA
| | - Yapei Huang
- Department of Pharmacology, Creighton University School of Medicine, Omaha, NE, USA
| | - Dennis W Wolff
- Kansas City University of Medicine and Biosciences-Joplin, Joplin, MO, USA
| | - Peter W Abel
- Department of Pharmacology, Creighton University School of Medicine, Omaha, NE, USA
| | - Yaping Tu
- Department of Pharmacology, Creighton University School of Medicine, Omaha, NE, USA.
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11
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Shaffo FC, Grodzki AC, Fryer AD, Lein PJ. Mechanisms of organophosphorus pesticide toxicity in the context of airway hyperreactivity and asthma. Am J Physiol Lung Cell Mol Physiol 2018; 315:L485-L501. [PMID: 29952220 PMCID: PMC6230874 DOI: 10.1152/ajplung.00211.2018] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2018] [Revised: 06/15/2018] [Accepted: 06/18/2018] [Indexed: 12/14/2022] Open
Abstract
Numerous epidemiologic studies have identified an association between occupational exposures to organophosphorus pesticides (OPs) and asthma or asthmatic symptoms in adults. Emerging epidemiologic data suggest that environmentally relevant levels of OPs may also be linked to respiratory dysfunction in the general population and that in utero and/or early life exposures to environmental OPs may increase risk for childhood asthma. In support of a causal link between OPs and asthma, experimental evidence demonstrates that occupationally and environmentally relevant OP exposures induce bronchospasm and airway hyperreactivity in preclinical models. Mechanistic studies have identified blockade of autoinhibitory M2 muscarinic receptors on parasympathetic nerves that innervate airway smooth muscle as one mechanism by which OPs induce airway hyperreactivity, but significant questions remain regarding the mechanism(s) by which OPs cause neuronal M2 receptor dysfunction and, more generally, how OPs cause persistent asthma, especially after developmental exposures. The goals of this review are to 1) summarize current understanding of OPs in asthma; 2) discuss mechanisms of OP neurotoxicity and immunotoxicity that warrant consideration in the context of OP-induced airway hyperreactivity and asthma, specifically, inflammatory responses, oxidative stress, neural plasticity, and neurogenic inflammation; and 3) identify critical data gaps that need to be addressed in order to better protect adults and children against the harmful respiratory effects of low-level OP exposures.
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Affiliation(s)
- Frances C Shaffo
- Department of Molecular Biosciences, University of California , Davis, California
| | - Ana Cristina Grodzki
- Department of Molecular Biosciences, University of California , Davis, California
| | - Allison D Fryer
- Pulmonary Critical Care Medicine, Department of Medicine, Oregon Health & Science University , Portland, Oregon
| | - Pamela J Lein
- Department of Molecular Biosciences, University of California , Davis, California
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12
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Patel KR, Bai Y, Trieu KG, Barrios J, Ai X. Targeting acetylcholine receptor M3 prevents the progression of airway hyperreactivity in a mouse model of childhood asthma. FASEB J 2017; 31:4335-4346. [PMID: 28619712 PMCID: PMC5602904 DOI: 10.1096/fj.201700186r] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2017] [Accepted: 05/30/2017] [Indexed: 12/19/2022]
Abstract
Asthma often progresses into adulthood from early-life episodes of adverse environmental exposures. However, how the injury to developing lungs contributes to the pathophysiology of persistent asthma remains poorly understood. In this study, we identified an age-related mechanism along the cholinergic nerve-airway smooth muscle (ASM) axis that underlies prolonged airway hyperreactivity (AHR) in mice. We showed that ASM continued to mature until ∼3 wk after birth. Coinciding with postnatal ASM maturation, there was a critical time window for the development of ASM hypercontractility after cholinergic stimulation. We found that allergen exposure in neonatal mice, but not in adult mice, elevated the level and activity of cholinergic nerves (termed neuroplasticity). We demonstrated that cholinergic neuroplasticity is necessary for the induction of persistent AHR after neonatal exposure during rescue assays in mice deficient in neuroplasticity. In addition, early intervention with cholinergic receptor muscarinic (ChRM)-3 blocker reversed the progression of AHR in the neonatal exposure model, whereas β2-adrenoceptor agonists had no such effect. Together, our findings demonstrate a functional relationship between cholinergic neuroplasticity and ASM contractile phenotypes that operates uniquely in early life to induce persistent AHR after allergen exposure. Targeting ChRM3 may have disease-modifying benefits in childhood asthma.-Patel, K. R., Bai, Y., Trieu, K. G., Barrios, J., Ai, X. Targeting acetylcholine receptor M3 prevents the progression of airway hyperreactivity in a mouse model of childhood asthma.
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Affiliation(s)
- Kruti R Patel
- Division of Neurology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Yan Bai
- Division of Pulmonary and Critical Care Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Kenneth G Trieu
- Division of Pulmonary and Critical Care Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Juliana Barrios
- Pulmonary Division, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Xingbin Ai
- Division of Pulmonary and Critical Care Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA;
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13
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Barrios J, Patel KR, Aven L, Achey R, Minns MS, Lee Y, Trinkaus-Randall VE, Ai X. Early life allergen-induced mucus overproduction requires augmented neural stimulation of pulmonary neuroendocrine cell secretion. FASEB J 2017; 31:4117-4128. [PMID: 28566470 DOI: 10.1096/fj.201700115r] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Accepted: 05/15/2017] [Indexed: 12/13/2022]
Abstract
Pulmonary neuroendocrine cells (PNECs) are the only innervated airway epithelial cells. To what extent neural innervation regulates PNEC secretion and function is unknown. Here, we discover that neurotrophin 4 (NT4) plays an essential role in mucus overproduction after early life allergen exposure by orchestrating PNEC innervation and secretion of GABA. We found that PNECs were the only cellular source of GABA in airways. In addition, PNECs expressed NT4 as a target-derived mechanism underlying PNEC innervation during development. Early life allergen exposure elevated the level of NT4 and caused PNEC hyperinnervation and nodose neuron hyperactivity. Associated with aberrant PNEC innervation, the authors discovered that GABA hypersecretion was required for the induction of mucin Muc5ac expression. In contrast, NT4-/- mice were protected from allergen-induced mucus overproduction and changes along the nerve-PNEC axis without any defects in inflammation. Last, GABA installation restored mucus overproduction in NT4-/- mice after early life allergen exposure. Together, our findings provide the first evidence for NT4-dependent neural regulation of PNEC secretion of GABA in a neonatal disease model. Targeting the nerve-PNEC axis may be a valid treatment strategy for mucus overproduction in airway diseases, such as childhood asthma.-Barrios, J., Patel, K. R., Aven, L., Achey, R., Minns, M. S., Lee, Y., Trinkaus-Randall, V. E., Ai, X. Early life allergen-induced mucus overproduction requires augmented neural stimulation of pulmonary neuroendocrine cell secretion.
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Affiliation(s)
- Juliana Barrios
- The Pulmonary Center, Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Kruti R Patel
- The Pulmonary Center, Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Linh Aven
- The Pulmonary Center, Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Rebecca Achey
- The Pulmonary Center, Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Martin S Minns
- Department of Biochemistry, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Yoonjoo Lee
- Department of Biochemistry, Boston University School of Medicine, Boston, Massachusetts, USA
| | | | - Xingbin Ai
- Division of Pulmonary and Critical Care Medicine, Brigham and Women's Hospital, Boston, Massachusetts, USA;
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14
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Paul E, Franco-Montoya ML, Paineau E, Angeletti B, Vibhushan S, Ridoux A, Tiendrebeogo A, Salome M, Hesse B, Vantelon D, Rose J, Canouï-Poitrine F, Boczkowski J, Lanone S, Delacourt C, Pairon JC. Pulmonary exposure to metallic nanomaterials during pregnancy irreversibly impairs lung development of the offspring. Nanotoxicology 2017; 11:484-495. [DOI: 10.1080/17435390.2017.1311381] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- Emmanuel Paul
- Inserm U955, Equipe 04, Créteil, France
- Faculté de Médecine, DHU A-TVB, IMRB, Université Paris Est Créteil, Créteil, France
| | - Marie-Laure Franco-Montoya
- Inserm U955, Equipe 04, Créteil, France
- Faculté de Médecine, DHU A-TVB, IMRB, Université Paris Est Créteil, Créteil, France
| | - Erwan Paineau
- Laboratoire de Physique des Solides, CNRS, University of Paris-Sud, Université Paris-Saclay, Orsay, France
| | - Bernard Angeletti
- CEREGE, Aix Marseille Université-CNRS-IRD-Collège de France, Aix-en-Provence, France
| | - Shamila Vibhushan
- Inserm U955, Equipe 04, Créteil, France
- Faculté de Médecine, DHU A-TVB, IMRB, Université Paris Est Créteil, Créteil, France
| | - Audrey Ridoux
- Inserm U955, Equipe 04, Créteil, France
- Faculté de Médecine, DHU A-TVB, IMRB, Université Paris Est Créteil, Créteil, France
| | - Arnaud Tiendrebeogo
- Inserm U955, Equipe 04, Créteil, France
- Faculté de Médecine, DHU A-TVB, IMRB, Université Paris Est Créteil, Créteil, France
| | | | - Bernhard Hesse
- European Synchrotron Radiation Facility, Grenoble, France
| | | | - Jérôme Rose
- CEREGE, Aix Marseille Université-CNRS-IRD-Collège de France, Aix-en-Provence, France
| | - Florence Canouï-Poitrine
- DHU A-TVB, IMRB, EA 7376 CEpiA (Clinical Epidemiology And Ageing Unit), Université Paris-Est Créteil (UPEC), Créteil, France
- Public Health Department, AP-HP, Henri-Mondor Teaching Hospital, Créteil, France
| | - Jorge Boczkowski
- Inserm U955, Equipe 04, Créteil, France
- Faculté de Médecine, DHU A-TVB, IMRB, Université Paris Est Créteil, Créteil, France
| | - Sophie Lanone
- Inserm U955, Equipe 04, Créteil, France
- Faculté de Médecine, DHU A-TVB, IMRB, Université Paris Est Créteil, Créteil, France
| | - Christophe Delacourt
- Inserm U955, Equipe 04, Créteil, France
- Faculté de Médecine, DHU A-TVB, IMRB, Université Paris Est Créteil, Créteil, France
| | - Jean-Claude Pairon
- Inserm U955, Equipe 04, Créteil, France
- Faculté de Médecine, DHU A-TVB, IMRB, Université Paris Est Créteil, Créteil, France
- Centre Hospitalier Intercommunal, Institut Santé-Travail Paris-Est, Créteil, France
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15
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Bauer SM. Atopic Eczema: Genetic Associations and Potential Links to Developmental Exposures. Int J Toxicol 2017; 36:187-198. [DOI: 10.1177/1091581817701075] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Atopic eczema (AE), or atopic dermatitis (AD), is a common inflammatory skin disease with a disrupted epidermal barrier and an allergic immune response. AD/AE is prominently characterized by a symptomatic itch and transient skin lesions. Infants compose a significant percentage affected. Two models have been proposed to explain AD/AE skin pathology: the gut microbiome-focused inside-outside model and the outside-inside model concentrating on the disrupted skin barrier/skin microbiome. Gene disruptions contributing to epidermal structure, as well as those in immune system genes, are implicated. Over 30 genes have been linked to AD/AE with Flg and Tmem79/Matt alterations being common. Other linked disruptions are in the interleukin-1 family of cytokines/receptors and the TH2 gene family of cytokines. Inheritable epigenetic modifications of the genes or associated proteins may also be involved. Skin barrier disruption and the allergic immune response have been the main foci in mechanistic studies of AD/AE, but the role of the environment is becoming more apparent. Thus, an examination of in utero exposures could be very helpful in understanding the heterogeneity of AD/AE. Although research is limited, there is evidence that developmental exposure to environmental tobacco smoke or phthalates may impact disease. Management for AD/AE includes topical corticosteroids and calcineurin inhibitors, which safely facilitate improvements in select individuals. Disease heterogeneity warrants continued research not only into elucidating disease mechanism(s), via identification of contributing genetic alterations, but also research to understand how/when these genetic alterations occur. This may lead to the cure that those affected by AD/AE eagerly await.
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Affiliation(s)
- Stephen M. Bauer
- Assistant Professor of Biology, Department of Biology, Belmont Abbey College, Belmont, NC, USA
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16
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Meuret AE, Kroll J, Ritz T. Panic Disorder Comorbidity with Medical Conditions and Treatment Implications. Annu Rev Clin Psychol 2017; 13:209-240. [PMID: 28375724 DOI: 10.1146/annurev-clinpsy-021815-093044] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Panic disorder (PD) is unique among the anxiety disorders in that panic symptoms are primarily of a physical nature. Consequently, comorbidity with medical illness is significant. This review examines the association between PD and medical illness. We identify shared pathophysiological and psychological correlates and illustrate how physiological activation in panic sufferers underlies their symptom experience in the context of the fight-or-flight response and beyond a situation-specific response pattern. We then review evidence for bodily symptom perception accuracy in PD. Prevalence of comorbidity for PD and medical illness is presented, with a focus on respiratory and cardiovascular illness, irritable bowel syndrome, and diabetes, followed by an outline for potential pathways of a bidirectional association. We conclude by illustrating commonalities in mediating mechanistic pathways and moderating risk factors across medical illnesses, and we discuss implications for diagnosis and treatment of both types of conditions.
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Affiliation(s)
- Alicia E Meuret
- Department of Psychology, Southern Methodist University, Dallas, Texas 75275;
| | - Juliet Kroll
- Department of Psychology, Southern Methodist University, Dallas, Texas 75275;
| | - Thomas Ritz
- Department of Psychology, Southern Methodist University, Dallas, Texas 75275;
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17
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Drummond D, Baravalle-Einaudi M, Lezmi G, Vibhushan S, Franco-Montoya ML, Hadchouel A, Boczkowski J, Delacourt C. Combined Effects of in Utero and Adolescent Tobacco Smoke Exposure on Lung Function in C57Bl/6J Mice. ENVIRONMENTAL HEALTH PERSPECTIVES 2017; 125:392-399. [PMID: 27814244 PMCID: PMC5332197 DOI: 10.1289/ehp54] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Revised: 10/10/2016] [Accepted: 10/13/2016] [Indexed: 05/30/2023]
Abstract
BACKGROUND Fetal determinants of airway function, such as in utero exposure to maternal cigarette smoke (CS), may create a predisposition to adult airflow obstruction and chronic obstructive pulmonary disease (COPD) in adulthood. It has been suggested that active smoking in adolescence and preexisting airflow obstruction have synergistic deleterious effects. OBJECTIVE We used a mouse model to investigate whether there is a synergistic effect of exposure to CS in utero and during adolescence on lung function. METHODS Female C57Bl/6J mice were exposed to CS or to filtered room air during pregnancy. Exposure to CS began 2 weeks before mating and continued until delivery. After birth, the pups were not exposed to CS until day 21 (D21). Between D21 and D49, corresponding to "adolescence," litters were randomized for an additional 4 weeks of exposure to CS. Lung morphometry, lung mechanics, and the expression of genes involved in senescence were evaluated in different subsets of mice on D21 and D49. RESULTS In utero exposure to CS induced significant lung function impairment by D21. CS exposure between D21 and D49 induced significant functional impairment only in mice exposed to CS prenatally. On D49, no difference was observed between subgroups in terms of lung p53, p16, p21, and Bax mRNA levels. CONCLUSIONS Our findings suggest that prenatal and adolescent CS exposure have a synergistic effect on lung function in mice. The combined effect did not appear to be a consequence of early pulmonary senescence. Citation: Drummond D, Baravalle-Einaudi M, Lezmi G, Vibhushan S, Franco-Montoya ML, Hadchouel A, Boczkowski J, Delacourt C. 2017. Combined effects of in utero and adolescent tobacco smoke exposure on lung function in C57Bl/6J mice. Environ Health Perspect 125:392-399; http://dx.doi.org/10.1289/EHP54.
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Affiliation(s)
- David Drummond
- INSERM (Institut National de la Santé et de la Recherche Médicale), U955, Equipe 04, IMRB (Institut Mondor de Recherche Biomédicale), Créteil, France
| | - Mélissa Baravalle-Einaudi
- INSERM (Institut National de la Santé et de la Recherche Médicale), U955, Equipe 04, IMRB (Institut Mondor de Recherche Biomédicale), Créteil, France
| | - Guillaume Lezmi
- INSERM (Institut National de la Santé et de la Recherche Médicale), U955, Equipe 04, IMRB (Institut Mondor de Recherche Biomédicale), Créteil, France
| | - Shamila Vibhushan
- INSERM (Institut National de la Santé et de la Recherche Médicale), U955, Equipe 04, IMRB (Institut Mondor de Recherche Biomédicale), Créteil, France
| | - Marie-Laure Franco-Montoya
- INSERM (Institut National de la Santé et de la Recherche Médicale), U955, Equipe 04, IMRB (Institut Mondor de Recherche Biomédicale), Créteil, France
| | - Alice Hadchouel
- INSERM (Institut National de la Santé et de la Recherche Médicale), U955, Equipe 04, IMRB (Institut Mondor de Recherche Biomédicale), Créteil, France
- Pneumologie Pédiatrique, Necker, AP-HP (Assistance Publique-Hôpitaux de Paris), France; Centre de Référence des Maladies Respiratoires Rares, Paris, France
- Université Paris-Descartes, Paris, France
| | - Jorge Boczkowski
- INSERM (Institut National de la Santé et de la Recherche Médicale), U955, Equipe 04, IMRB (Institut Mondor de Recherche Biomédicale), Créteil, France
| | - Christophe Delacourt
- INSERM (Institut National de la Santé et de la Recherche Médicale), U955, Equipe 04, IMRB (Institut Mondor de Recherche Biomédicale), Créteil, France
- Pneumologie Pédiatrique, Necker, AP-HP (Assistance Publique-Hôpitaux de Paris), France; Centre de Référence des Maladies Respiratoires Rares, Paris, France
- Université Paris-Descartes, Paris, France
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18
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Patel KR, Aven L, Shao F, Krishnamoorthy N, Duvall MG, Levy BD, Ai X. Mast cell-derived neurotrophin 4 mediates allergen-induced airway hyperinnervation in early life. Mucosal Immunol 2016; 9:1466-1476. [PMID: 26860818 PMCID: PMC4980297 DOI: 10.1038/mi.2016.11] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2015] [Accepted: 01/04/2016] [Indexed: 02/04/2023]
Abstract
Asthma often progresses from early episodes of insults. How early-life events connect to long-term airway dysfunction remains poorly understood. We demonstrated previously that increased neurotrophin 4 (NT4) levels following early-life allergen exposure cause persistent changes in airway smooth muscle (ASM) innervation and airway hyper-reactivity (AHR) in mice. Herein, we identify pulmonary mast cells as a key source of aberrant NT4 expression following early insults. NT4 is selectively expressed by ASM and mast cells in mice, nonhuman primates, and humans. We show in mice that mast cell-derived NT4 is dispensable for ASM innervation during development. However, upon insults, mast cells expand in number and degranulate to release NT4 and thus become the major source of NT4 under pathological condition. Adoptive transfer of wild-type mast cells, but not NT4-/- mast cells restores ASM hyperinnervation and AHR in KitW-sh/W-sh mice following early-life insults. Notably, an infant nonhuman primate model of asthma also exhibits ASM hyperinnervation associated with the expansion and degranulation of mast cells. Together, these findings identify an essential role of mast cells in mediating ASM hyperinnervation following early-life insults by producing NT4. This role may be evolutionarily conserved in linking early insults to long-term airway dysfunction.
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Affiliation(s)
- Kruti R. Patel
- The Pulmonary Center, Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Linh Aven
- The Pulmonary Center, Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Fengzhi Shao
- The Pulmonary Center, Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, USA
| | - Nandini Krishnamoorthy
- Division of Pulmonary and Critical Care Medicine, Brigham & Women's Hospital, Harvard Medical School, 75 Francis Street, Boston, Massachusetts, USA
| | - Melody G. Duvall
- Division of Critical Care Medicine, Department of Anesthesia, Perioperative and Pain Medicine, Boston Children's Hospital, Boston, Massachusetts, USA.,Division of Pulmonary and Critical Care Medicine, Brigham & Women's Hospital, Harvard Medical School, 75 Francis Street, Boston, Massachusetts, USA
| | - Bruce D. Levy
- Division of Pulmonary and Critical Care Medicine, Brigham & Women's Hospital, Harvard Medical School, 75 Francis Street, Boston, Massachusetts, USA
| | - Xingbin Ai
- The Pulmonary Center, Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, USA.,Division of Pulmonary and Critical Care Medicine, Brigham & Women's Hospital, Harvard Medical School, 75 Francis Street, Boston, Massachusetts, USA
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19
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Wu ZX, Hunter DD, Batchelor TP, Dey RD. Side-stream tobacco smoke-induced airway hyperresponsiveness in early postnatal period is involved nerve growth factor. Respir Physiol Neurobiol 2016; 223:1-8. [PMID: 26638730 DOI: 10.1016/j.resp.2015.11.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2015] [Revised: 11/11/2015] [Accepted: 11/12/2015] [Indexed: 12/28/2022]
Abstract
Epidemiological studies have shown that children are more susceptible to adverse respiratory effects of passive smoking than adults. The goal of this study is to elucidate the possible neural mechanism induced by exposure to passive smoking during early life. Postnatal day (PD) 2 and PD 21 mice were exposed to side-stream tobacco smoke (SS), a surrogate to secondhand smoke, or filtered air (FA) for 10 consecutive days. Pulmonary function, substance P (SP) airway innervation, neurotrophin gene expression in lung and nerve growth factor (NGF) release in bronchoalveolar lavage (BAL) fluid were measured at different times after the last SS or FA exposure. Exposure to SS significantly altered pulmonary function in PD2, accompanied with an enhanced SP innervation in airway. However, exposure to SS during the later developmental period (PD21) did not appear to affect pulmonary function and SP innervation of the airways. Interestingly, SS exposure in PD2 group significantly induced an increased gene expression on NGF, and decreased NGF receptor P75 in lung; parallel with high levels of NGF protein in BAL. Furthermore, pretreatment with NGF antibody significantly diminished SS-induced airway hyperresponsivenss and the increased SP airway innervation in the PD2 group. These findings suggest that enhanced NGF released in the lung contributes to SS-enhanced SP tracheal innervation and airway responsiveness in early life.
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Affiliation(s)
- Z-X Wu
- Department of Neurobiology and Anatomy, Robert C. Byrd Health Sciences Center, West Virginia University, Morgantown, WV 26506, United States.
| | - D D Hunter
- Department of Neurobiology and Anatomy, Robert C. Byrd Health Sciences Center, West Virginia University, Morgantown, WV 26506, United States
| | - T P Batchelor
- Department of Neurobiology and Anatomy, Robert C. Byrd Health Sciences Center, West Virginia University, Morgantown, WV 26506, United States
| | - R D Dey
- Department of Neurobiology and Anatomy, Robert C. Byrd Health Sciences Center, West Virginia University, Morgantown, WV 26506, United States
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20
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Zhao L, Zhuang J, Zang N, Lin Y, Lee LY, Xu F. Prenatal nicotinic exposure upregulates pulmonary C-fiber NK1R expression to prolong pulmonary C-fiber-mediated apneic response. Toxicol Appl Pharmacol 2016; 290:107-15. [PMID: 26524655 PMCID: PMC4732869 DOI: 10.1016/j.taap.2015.10.023] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2015] [Revised: 09/06/2015] [Accepted: 10/29/2015] [Indexed: 01/15/2023]
Abstract
Prenatal nicotinic exposure (PNE) prolongs bronchopulmonary C-fiber (PCF)-mediated apneic response to intra-atrial bolus injection of capsaicin in rat pups. The relevant mechanisms remain unclear. Pulmonary substance P and adenosine and their receptors (neurokinin-A receptor, NK1R and ADA1 receptor, ADA1R) and transient receptor potential cation channel subfamily V member 1 (TRPV1) expressed on PCFs are critical for PCF sensitization and/or activation. Here, we compared substance P and adenosine in BALF and NK1R, ADA1R, and TRPV1 expression in the nodose/jugular (N/J) ganglia (vagal pulmonary C-neurons retrogradely labeled) between Ctrl and PNE pups. We found that PNE failed to change BALF substance P and adenosine content, but significantly upregulated both mRNA and protein TRPV1 and NK1R in the N/J ganglia and only NK1R mRNA in pulmonary C-neurons. To define the role of NK1R in the PNE-induced PCF sensitization, the apneic response to capsaicin (i.v.) without or with pretreatment of SR140333 (a peripheral and selective NK1R antagonist) was compared and the prolonged apnea by PNE significantly shortened by SR140333. To clarify if the PNE-evoked responses depended on action of nicotinic acetylcholine receptors (nAChRs), particularly α7nAChR, mecamylamine or methyllycaconitine (a general nAChR or a selective α7nAChR antagonist) was administrated via another mini-pump over the PNE period. Mecamylamine or methyllycaconitine eliminated the PNE-evoked mRNA and protein responses. Our data suggest that PNE is able to elevate PCF NK1R expression via activation of nAChRs, especially α7nAChR, which likely contributes to sensitize PCFs and prolong the PCF-mediated apneic response to capsaicin.
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MESH Headings
- Adenosine/pharmacology
- Animals
- Animals, Newborn
- Apnea/drug therapy
- Bronchoalveolar Lavage Fluid
- Capsaicin/pharmacology
- Female
- Ganglia/drug effects
- Ganglia/metabolism
- Lung/drug effects
- Male
- Nerve Fibers, Unmyelinated/drug effects
- Nerve Fibers, Unmyelinated/metabolism
- Nicotine/blood
- Nicotine/toxicity
- Pregnancy
- Prenatal Exposure Delayed Effects
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Rats
- Rats, Sprague-Dawley
- Receptors, Neurokinin-1/genetics
- Receptors, Neurokinin-1/metabolism
- Receptors, Neurokinin-2/genetics
- Receptors, Neurokinin-2/metabolism
- Substance P/pharmacology
- TRPV Cation Channels/genetics
- TRPV Cation Channels/metabolism
- Up-Regulation
- Vagus Nerve/drug effects
- Vagus Nerve/metabolism
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Affiliation(s)
- Lei Zhao
- Pathophysiology Program, Lovelace Respiratory Research Institute, Albuquerque, NM, USA
| | - Jianguo Zhuang
- Pathophysiology Program, Lovelace Respiratory Research Institute, Albuquerque, NM, USA
| | - Na Zang
- Pathophysiology Program, Lovelace Respiratory Research Institute, Albuquerque, NM, USA
| | - Yong Lin
- Pathophysiology Program, Lovelace Respiratory Research Institute, Albuquerque, NM, USA
| | - Lu-Yuan Lee
- Department of Physiology, University of Kentucky, Lexington, KY, USA
| | - Fadi Xu
- Pathophysiology Program, Lovelace Respiratory Research Institute, Albuquerque, NM, USA; Department of Physiology, University of Kentucky, Lexington, KY, USA.
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21
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Cao J, Xu X, Hylkema MN, Zeng EY, Sly PD, Suk WA, Bergman Å, Huo X. Early-life Exposure to Widespread Environmental Toxicants and Health Risk: A Focus on the Immune and Respiratory Systems. Ann Glob Health 2016; 82:119-31. [PMID: 27325070 DOI: 10.1016/j.aogh.2016.01.023] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Evidence has accumulated that exposure to widespread environmental toxicants, such as heavy metals, persistent organic pollutants, and tobacco smoke adversely affect fetal development and organ maturation, even after birth. The developing immune and respiratory systems are more sensitive to environmental toxicants due to their long-term physical development, starting from the early embryonic stage and persisting into early postnatal life, which requires complex signaling pathways that control proliferation and differentiation of highly heterogeneous cell types. In this review, we summarize the effect of early-life exposure to several widespread environmental toxicants on immune and lung development before and after birth, including the effects on immune cell counts, baseline characteristics of cell-mediated and humoral immunity, and alteration of lung structure and function in offspring. We also review evidence supporting the association between early-life exposure to environmental toxicants and risk for immune-related diseases and lung dysfunction in offspring in later life.
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Affiliation(s)
- Junjun Cao
- Laboratory of Environmental Medicine and Developmental Toxicology, Shantou University Medical College, Shantou, China; Department of Pathology and Medical Biology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands; GRIAC Research Institute, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Xijin Xu
- Laboratory of Environmental Medicine and Developmental Toxicology, Shantou University Medical College, Shantou, China.
| | - Machteld N Hylkema
- Department of Pathology and Medical Biology, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands; GRIAC Research Institute, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Eddy Y Zeng
- School of Environment, Guangzhou Key Laboratory of Environmental Exposure and Health, Guangdong Key Laboratory of Environmental Pollution and Health, Jinan University, Guangzhou, China
| | - Peter D Sly
- Children's Health and Environment Program, Child Health Research Centre, The University of Queensland, Queensland, Australia
| | - William A Suk
- Hazardous Substances Research Branch, Superfund Research Program, National Institute for Environmental Health Sciences, National Institutes of Health, Bethesda, MD
| | - Åke Bergman
- Swedish Toxicology Sciences Research Center (Swetox), Södertälje, Sweden
| | - Xia Huo
- Laboratory of Environmental Medicine and Developmental Toxicology, Shantou University Medical College, Shantou, China; School of Environment, Guangzhou Key Laboratory of Environmental Exposure and Health, Guangdong Key Laboratory of Environmental Pollution and Health, Jinan University, Guangzhou, China
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In Utero Cigarette Smoke Affects Allergic Airway Disease But Does Not Alter the Lung Methylome. PLoS One 2015; 10:e0144087. [PMID: 26642056 PMCID: PMC4671614 DOI: 10.1371/journal.pone.0144087] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Accepted: 11/12/2015] [Indexed: 11/19/2022] Open
Abstract
Prenatal and postnatal cigarette smoke exposure enhances the risk of developing asthma. Despite this as well as other smoking related risks, 11% of women still smoke during pregnancy. We hypothesized that cigarette smoke exposure during prenatal development generates long lasting differential methylation altering transcriptional activity that correlates with disease. In a house dust mite (HDM) model of allergic airway disease, we measured airway hyperresponsiveness (AHR) and airway inflammation between mice exposed prenatally to cigarette smoke (CS) or filtered air (FA). DNA methylation and gene expression were then measured in lung tissue. We demonstrate that HDM-treated CS mice develop a more severe allergic airway disease compared to HDM-treated FA mice including increased AHR and airway inflammation. While DNA methylation changes between the two HDM-treated groups failed to reach genome-wide significance, 99 DMRs had an uncorrected p-value < 0.001. 6 of these 99 DMRs were selected for validation, based on the immune function of adjacent genes, and only 2 of the 6 DMRs confirmed the bisulfite sequencing data. Additionally, genes near these 6 DMRs (Lif, Il27ra, Tle4, Ptk7, Nfatc2, and Runx3) are differentially expressed between HDM-treated CS mice and HDM-treated FA mice. Our findings confirm that prenatal exposure to cigarette smoke is sufficient to modify allergic airway disease; however, it is unlikely that specific methylation changes account for the exposure-response relationship. These findings highlight the important role in utero cigarette smoke exposure plays in the development of allergic airway disease.
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Lee JW, Jaffar Z, Pinkerton KE, Porter V, Postma B, Ferrini M, Holian A, Roberts K, Cho YH. Alterations in DNA methylation and airway hyperreactivity in response to in utero exposure to environmental tobacco smoke. Inhal Toxicol 2015; 27:724-30. [PMID: 26525176 PMCID: PMC4760648 DOI: 10.3109/08958378.2015.1104402] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Growing evidence indicates that prenatal exposure to maternal smoking is a risk factor for the development of asthma in children. However, the effects of prenatal environmental tobacco smoke (ETS) exposure on the genome and lung immune cells are unclear. This study aims to determine whether in utero ETS exposure alters DNA methylation patterns and increases airway hyperreactivity (AHR) and inflammation. Pregnant C57BL/6 mice were exposed daily to a concentration of 1.0 mg/m(3) ETS. AHR was determined in the 6-week-old offspring by measurement of airway resistance. Global and gene promoter methylation levels in lung DNA from offspring were analyzed by luminometric methylation and pyrosequencing assays, respectively. Offspring exposed to ETS showed a marked increase in the number of alveolar macrophages in the bronchoalveolar lavage fluid and level of IL-13 in the airways compared with offspring of filtered-air exposed dams (controls). ETS exposure significantly augmented AHR compared with controls. In the methylation analysis, ETS-exposed offspring had a significantly lower level of global DNA methylation than the controls. We observed a significant increase in IFN-γ, and significant decrease in IL-13 methylation levels in the ETS group compared with controls. Collectively, these data suggest that in utero ETS exposure increases the risk of pulmonary inflammation and AHR through altered DNA methylation, but additional studies are needed to fully determine the causal link between changes in methylation and cytokines levels, as well as AHR.
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Affiliation(s)
- Joong Won Lee
- Department of Biomedical and Pharmaceutical Sciences, Center for Environmental Health Sciences, University of Montana, Missoula, MT, USA
| | - Zeina Jaffar
- Department of Biomedical and Pharmaceutical Sciences, Center for Environmental Health Sciences, University of Montana, Missoula, MT, USA
| | - Kent E. Pinkerton
- Department of Anatomy, Physiology and Cell Biology, Center for Health and the Environment, University of California, Davis, CA, USA
| | - Virginia Porter
- Department of Biomedical and Pharmaceutical Sciences, Center for Environmental Health Sciences, University of Montana, Missoula, MT, USA
| | - Britten Postma
- Department of Biomedical and Pharmaceutical Sciences, Center for Environmental Health Sciences, University of Montana, Missoula, MT, USA
| | - Maria Ferrini
- Department of Biomedical and Pharmaceutical Sciences, Center for Environmental Health Sciences, University of Montana, Missoula, MT, USA
| | - Andrij Holian
- Department of Biomedical and Pharmaceutical Sciences, Center for Environmental Health Sciences, University of Montana, Missoula, MT, USA
| | - Kevan Roberts
- Department of Biomedical and Pharmaceutical Sciences, Center for Environmental Health Sciences, University of Montana, Missoula, MT, USA
| | - Yoon Hee Cho
- Department of Biomedical and Pharmaceutical Sciences, Center for Environmental Health Sciences, University of Montana, Missoula, MT, USA
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Xiao L, Kish VL, Benders KM, Wu ZX. Prenatal and Early Postnatal Exposure to Cigarette Smoke Decreases BDNF/TrkB Signaling and Increases Abnormal Behaviors Later in Life. Int J Neuropsychopharmacol 2015; 19:pyv117. [PMID: 26503133 PMCID: PMC4886663 DOI: 10.1093/ijnp/pyv117] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/17/2015] [Accepted: 10/07/2015] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Cigarette smoke exposure during prenatal and early postnatal periods increases the incidence of a variety of abnormal behaviors later in life. The purpose of this study was to identify the possible critical period of susceptibility to cigarette smoke exposure and evaluate the possibe effects of cigarette smoke during early life on brain-derived neurotrophic factor/neurotrophic tyrosine kinase receptor B signaling in the brain. METHODS Three different age of imprinting control region mice were exposed to cigarette smoke or filtered air for 10 consecutive days beginning on either gestational day 7 by maternal exposure, or postnatal days 2 or 21 by direct inhalation. A series of behavioral profiles and neurotrophins in brain were measured 24 hours after mice received acute restraint stress for 1 hour on postnatal day 59. RESULTS Cigarette smoke exposure in gestational day 7 and postnatal day 2 produced depression-like behaviors as evidenced by significantly increased immobility in both tail suspension and forced-swim test. Increased entry latencies, but not ambulation in the open field test, were also observed in the gestational day 7 and postnatal day 2 cigarette smoke exposure groups. Genetic analysis showed that gestational day 7 cigarette smoke exposure significantly altered mRNA level of brain-derived neurotrophic factor/tyrosine kinase receptor B in the hippocampus. However, behavioral profiles and brain-derived neurotrophic factor/tyrosine kinase receptor B signaling were not significantly changed in PND21 cigarette smoke exposure group compared with FA group. CONCLUSIONS These results suggest that a critical period of susceptibility to cigarette smoke exposure exists in the prenatal and early postnatal period, which results a downregulation in brain-derived neurotrophic factor/tyrosine kinase receptor B signaling in the hippocampus and enhances depression-like behaviors later in life.
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Affiliation(s)
| | | | | | - Zhong-Xin Wu
- Department of Neurobiology and Anatomy, Robert C. Byrd Health Sciences Center, West Virginia University, Morgantown, WV
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HIF-1α Plays a Critical Role in the Gestational Sidestream Smoke-Induced Bronchopulmonary Dysplasia in Mice. PLoS One 2015; 10:e0137757. [PMID: 26361040 PMCID: PMC4567349 DOI: 10.1371/journal.pone.0137757] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2015] [Accepted: 08/20/2015] [Indexed: 11/24/2022] Open
Abstract
Rationale Smoking during pregnancy increases the risk of bronchopulmonary dysplasia (BPD) and, in mice, gestational exposure to sidestream cigarette smoke (SS) induces BPD-like condition characterized by alveolar simplification, impaired angiogenesis, and suppressed surfactant protein production. Normal fetal development occurs in a hypoxic environment and nicotinic acetylcholine receptors (nAChRs) regulate the hypoxia-inducible factor (HIF)-1α that controls apoptosis and angiogenesis. To understand SS-induced BPD, we hypothesized that gestational SS affected alveolar development through HIF-1α. Methods Pregnant BALB/c mice were exposed to air (control) or SS throughout the gestational period and the 7-day-old lungs of the progeny were examined. Results Gestational SS increased apoptosis of alveolar and airway epithelial cells. This response was associated with increased alveolar volumes, higher levels of proapoptotic factors (FOXO3a, HIPK2, p53, BIM, BIK, and BAX) and the antiangiogenic factor (GAX), and lower levels of antiapoptotic factors (Akt-PI3K, NF-κB, HIF-1α, and Bcl-2) in the lung. Although gestational SS increased the cells containing the proangiogenic bombesin-like-peptide, it markedly decreased the expression of its receptor GRPR in the lung. The effects of SS on apoptosis were attenuated by the nAChR antagonist mecamylamine. Conclusions Gestational SS-induced BPD is potentially regulated by nAChRs and associated with downregulation of HIF-1α, increased apoptosis of epithelial cells, and increased alveolar volumes. Thus, in mice, exposure to sidestream tobacco smoke during pregnancy promotes BPD-like condition that is potentially mediated through the nAChR/HIF-1α pathway.
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26
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Zhuang J, Zhao L, Zang N, Xu F. Prenatal nicotinic exposure augments cardiorespiratory responses to activation of bronchopulmonary C-fibers. Am J Physiol Lung Cell Mol Physiol 2015; 308:L922-30. [PMID: 25747962 PMCID: PMC4421788 DOI: 10.1152/ajplung.00241.2014] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2014] [Accepted: 03/01/2015] [Indexed: 12/26/2022] Open
Abstract
Rat pups prenatally exposed to nicotine (PNE) present apneic (lethal ventilatory arrest) responses during severe hypoxia. To clarify whether these responses are of central origin, we tested PNE effects on ventilation and diaphragm electromyography (EMGdi) during hypoxia in conscious rat pups. PNE produced apnea (lethal ventilatory arrest) identical to EMGdi silencing during hypoxia, indicating a central origin of this apneic response. We further asked whether PNE would sensitize bronchopulmonary C-fibers (PCFs), a key player in generating central apnea, with increase of the density and transient receptor potential cation channel subfamily V member 1 (TRPV1) expression of C-fibers/neurons in the nodose/jugular (N/J) ganglia and neurotrophic factors in the airways and lungs. We compared 1) ventilatory and pulmonary C-neural responses to right atrial bolus injection of capsaicin (CAP, 0.5 μg/kg), 2) bronchial substance P-immunoreactive (SP-IR) fiber density, 3) gene and protein expressions of TRPV1 in the ganglia, and 4) nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF) protein in bronchoalveolar lavage fluid (BALF) and TrkA and TrkB genes in the ganglia between control and PNE pups. PNE markedly strengthened the PCF-mediated apneic response to CAP via increasing pulmonary C-neural sensitivity. PNE also enhanced bronchial SP-IR fiber density and N/J ganglia neural TRPV1 expression associated with increased gene expression of TrkA in the N/G ganglia and decreased NGF and BDNF in BALF. Our results suggest that PNE enhances PCF sensitivity likely through increasing PCF density and TRPV1 expression via upregulation of neural TrkA and downregulation of pulmonary BDNF, which may contribute to the PNE-promoted central apnea (lethal ventilatory arrest) during hypoxia.
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Affiliation(s)
- Jianguo Zhuang
- Pathophysiology Program, Lovelace Respiratory Research Institute, Albuquerque, New Mexico
| | - Lei Zhao
- Pathophysiology Program, Lovelace Respiratory Research Institute, Albuquerque, New Mexico
| | - Na Zang
- Pathophysiology Program, Lovelace Respiratory Research Institute, Albuquerque, New Mexico
| | - Fadi Xu
- Pathophysiology Program, Lovelace Respiratory Research Institute, Albuquerque, New Mexico
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Krauss-Etschmann S, Meyer KF, Dehmel S, Hylkema MN. Inter- and transgenerational epigenetic inheritance: evidence in asthma and COPD? Clin Epigenetics 2015; 7:53. [PMID: 26052354 PMCID: PMC4456695 DOI: 10.1186/s13148-015-0085-1] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2015] [Accepted: 04/09/2015] [Indexed: 12/21/2022] Open
Abstract
Evidence is now emerging that early life environment can have lifelong effects on metabolic, cardiovascular, and pulmonary function in offspring, a concept also known as fetal or developmental programming. In mammals, developmental programming is thought to occur mainly via epigenetic mechanisms, which include DNA methylation, histone modifications, and expression of non-coding RNAs. The effects of developmental programming can be induced by the intrauterine environment, leading to intergenerational epigenetic effects from one generation to the next. Transgenerational epigenetic inheritance may be considered when developmental programming is transmitted across generations that were not exposed to the initial environment which triggered the change. So far, inter- and transgenerational programming has been mainly described for cardiovascular and metabolic disease risk. In this review, we discuss available evidence that epigenetic inheritance also occurs in respiratory diseases, using asthma and chronic obstructive pulmonary disease (COPD) as examples. While multiple epidemiological as well as animal studies demonstrate effects of 'toxic' intrauterine exposure on various asthma-related phenotypes in the offspring, only few studies link epigenetic marks to the observed phenotypes. As epigenetic marks may distinguish individuals most at risk of later disease at early age, it will enable early intervention strategies to reduce such risks. To achieve this goal further, well designed experimental and human studies are needed.
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Affiliation(s)
- Susanne Krauss-Etschmann
- />Comprehensive Pneumology Center, Helmholtz Center Munich and Children’s Hospital of Ludwig-Maximilians University, Max-Lebsche-Platz 31, 81377 Munich, Germany
- />Priority Area Asthma & Allergy, Leibniz Center for Medicine and Biosciences, Research Center Borstel and Christian Albrechts University Kiel, Airway Research Center North, Member of the German Center for Lung Research, Parkallee 1-40, Borstel, Germany
| | - Karolin F Meyer
- />Department of Pathology and Medical Biology, University of Groningen, University Medical Center Groningen, Hanzeplein 1, Groningen, The Netherlands
- />University of Groningen, GRIAC Research Institute, University Medical Center Groningen, Hanzeplein 1, Groningen, The Netherlands
| | - Stefan Dehmel
- />Comprehensive Pneumology Center, Helmholtz Center Munich and Children’s Hospital of Ludwig-Maximilians University, Max-Lebsche-Platz 31, 81377 Munich, Germany
| | - Machteld N Hylkema
- />Department of Pathology and Medical Biology, University of Groningen, University Medical Center Groningen, Hanzeplein 1, Groningen, The Netherlands
- />University of Groningen, GRIAC Research Institute, University Medical Center Groningen, Hanzeplein 1, Groningen, The Netherlands
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Aven L, Paez-Cortez J, Achey R, Krishnan R, Ram-Mohan S, Cruikshank WW, Fine A, Ai X. An NT4/TrkB-dependent increase in innervation links early-life allergen exposure to persistent airway hyperreactivity. FASEB J 2014; 28:897-907. [PMID: 24221086 PMCID: PMC3898648 DOI: 10.1096/fj.13-238212] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2013] [Accepted: 11/04/2013] [Indexed: 11/11/2022]
Abstract
Children who are exposed to environmental respiratory insults often develop asthma that persists into adulthood. In this study, we used a neonatal mouse model of ovalbumin (OVA)-induced allergic airway inflammation to understand the long-term effects of early childhood insults on airway structure and function. We showed that OVA sensitization and challenge in early life led to a 2-fold increase in airway smooth muscle (ASM) innervation (P<0.05) and persistent airway hyperreactivity (AHR). In contrast, OVA exposure in adult life elicited short-term AHR without affecting innervation levels. We found that postnatal ASM innervation required neurotrophin (NT)-4 signaling through the TrkB receptor and that early-life OVA exposure significantly elevated NT4 levels and TrkB signaling by 5- and 2-fold, respectively, to increase innervation. Notably, blockade of NT4/TrkB signaling in OVA-exposed pups prevented both acute and persistent AHR without affecting baseline airway function or inflammation. Furthermore, biophysical assays using lung slices and isolated cells demonstrated that NT4 was necessary for hyperreactivity of ASM induced by early-life OVA exposure. Together, our findings show that the NT4/TrkB-dependent increase in innervation plays a critical role in the alteration of the ASM phenotype during postnatal growth, thereby linking early-life allergen exposure to persistent airway dysfunction.
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Affiliation(s)
- Linh Aven
- 1The Pulmonary Center, Department of Medicine, Boston University School of Medicine, 72 East Concord Street, Boston, MA 02118, USA.
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Undem BJ, Taylor-Clark T. Mechanisms underlying the neuronal-based symptoms of allergy. J Allergy Clin Immunol 2014; 133:1521-34. [PMID: 24433703 DOI: 10.1016/j.jaci.2013.11.027] [Citation(s) in RCA: 123] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2013] [Revised: 11/05/2013] [Accepted: 11/13/2013] [Indexed: 12/13/2022]
Abstract
Persons with allergies present with symptoms that often are the result of alterations in the nervous system. Neuronally based symptoms depend on the organ in which the allergic reaction occurs but can include red itchy eyes, sneezing, nasal congestion, rhinorrhea, coughing, bronchoconstriction, airway mucus secretion, dysphagia, altered gastrointestinal motility, and itchy swollen skin. These symptoms occur because mediators released during an allergic reaction can interact with sensory nerves, change processing in the central nervous system, and alter transmission in sympathetic, parasympathetic, and enteric autonomic nerves. In addition, evidence supports the idea that in some subjects this neuromodulation is, for reasons poorly understood, upregulated such that the same degree of nerve stimulus causes a larger effect than seen in healthy subjects. There are distinctions in the mechanisms and nerve types involved in allergen-induced neuromodulation among different organ systems, but general principles have emerged. The products of activated mast cells, other inflammatory cells, and resident cells can overtly stimulate nerve endings, cause long-lasting changes in neuronal excitability, increase synaptic efficacy, and also change gene expression in nerves, resulting in phenotypically altered neurons. A better understanding of these processes might lead to novel therapeutic strategies aimed at limiting the suffering of those with allergies.
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Affiliation(s)
- Bradley J Undem
- Division of Allergy & Clinical Immunology, Johns Hopkins School of Medicine, Baltimore, Md.
| | - Thomas Taylor-Clark
- Department of Molecular Pharmacology & Physiology, Morsani College of Medicine, University of South Florida, Tampa, Fla
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Selgrade MK, Blain RB, Fedak KM, Cawley MA. Potential risk of asthma associated with in utero exposure to xenobiotics. ACTA ACUST UNITED AC 2014; 99:1-13. [PMID: 23723168 DOI: 10.1002/bdrc.21028] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2013] [Accepted: 03/06/2013] [Indexed: 12/27/2022]
Abstract
The incidence of asthma, a complex disease and significant public health problem, has been increasing over the last 30 years for unknown reasons. Changes in environmental exposures or lifestyle may be involved. In some cases asthma may originate in utero or in early life. Associations have been found between in utero exposures to several xenobiotics and increased risk of asthma. There is convincing evidence that maternal smoking and/or in utero and perinatal exposure to environmental tobacco smoke are associated with increased risk of asthma. Similar effects have been demonstrated in animal models of allergic asthma. Evidence also suggests that in utero and/or early-life exposures to various ambient air pollutants may increase the risk of asthma although supporting animal data are very limited. A few studies have suggested that in utero exposure to acetaminophen is associated with increased risk of asthma; however, animal data are lacking. Various vitamin deficiencies and supplements during pregnancy have been studied. In general, it appears that vitamins A, C, and E have protective effects and vitamins D and B may, in some instances, increase the risk, but the data are not conclusive. Some studies related to in utero exposures to polychlorinated biphenyls and bisphenol A and asthma risk are also reported. The underlying mechanisms for an association between xenobiotic exposures and asthma remain a matter of speculation. Genetic predisposition and epigenetic changes have been explored. The developing immune, respiratory, and nervous systems are potential targets. Oxidative stress and modulation of inflammation are thought to be involved.
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Pedersen M, Siroux V, Pin I, Charles MA, Forhan A, Hulin A, Galineau J, Lepeule J, Giorgis-Allemand L, Sunyer J, Annesi-Maesano I, Slama R. Does consideration of larger study areas yield more accurate estimates of air pollution health effects? An illustration of the bias-variance trade-off in air pollution epidemiology. ENVIRONMENT INTERNATIONAL 2013; 60:23-30. [PMID: 23994839 DOI: 10.1016/j.envint.2013.07.005] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2012] [Revised: 06/22/2013] [Accepted: 07/06/2013] [Indexed: 06/02/2023]
Abstract
BACKGROUND Spatially-resolved air pollution models can be developed in large areas. The resulting increased exposure contrasts and population size offer opportunities to better characterize the effect of atmospheric pollutants on respiratory health. However the heterogeneity of these areas may also enhance the potential for confounding. We aimed to discuss some analytical approaches to handle this trade-off. METHODS We modeled NO2 and PM10 concentrations at the home addresses of 1082 pregnant mothers from EDEN cohort living in and around urban areas, using ADMS dispersion model. Simulations were performed to identify the best strategy to limit confounding by unmeasured factors varying with area type. We examined the relation between modeled concentrations and respiratory health in infants using regression models with and without adjustment or interaction terms with area type. RESULTS Simulations indicated that adjustment for area limited the bias due to unmeasured confounders varying with area at the costs of a slight decrease in statistical power. In our cohort, rural and urban areas differed for air pollution levels and for many factors associated with respiratory health and exposure. Area tended to modify effect measures of air pollution on respiratory health. CONCLUSIONS Increasing the size of the study area also increases the potential for residual confounding. Our simulations suggest that adjusting for type of area is a good option to limit residual confounding due to area-associated factors without restricting the area size. Other statistical approaches developed in the field of spatial epidemiology are an alternative to control for poorly-measured spatially-varying confounders.
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Affiliation(s)
- Marie Pedersen
- Centre for Research in Environmental Epidemiology (CREAL), Parc de Recerca Biomèdica de Barcelona, Doctor Aiguader 88, 08003 Barcelona, Spain; IMIM (Hospital del Mar Research Institute), Passeig Marítim 25-29, 08003 Barcelona, Spain; CIBER Epidemiologia y Salud Pública (CIBERESP), Spain; INSERM, U823, Team of Environmental Epidemiology Applied to Reproduction and Respiratory Health, Institute Albert Bonniot, 38042 Grenoble, France
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Alexander M, Karmaus W, Holloway JW, Zhang H, Roberts G, Kurukulaaratchy RJ, Arshad SH, Ewart S. Effect of GSTM2-5 polymorphisms in relation to tobacco smoke exposures on lung function growth: a birth cohort study. BMC Pulm Med 2013; 13:56. [PMID: 24004509 PMCID: PMC3846453 DOI: 10.1186/1471-2466-13-56] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2012] [Accepted: 08/20/2013] [Indexed: 02/07/2023] Open
Abstract
Background Genetic variation within GSTM2-5 genes may interfere with detoxification of environmental compounds, thereby having a detrimental effect on lung function following exposures such as tobacco smoke. We aim to investigate the influence of variants and associated methylation in the GSTM gene cluster with changes in lung function growth during adolescence. Methods Growth in forced expiratory volume (FEV1), forced vital capacity (FVC), and change in FEV1/FVC ratio measures were obtained from children in the Isle of Wight birth cohort at ages 10 and 18. Illumina GoldenGate assays were used to genotype 10 tagging polymorphisms from GSTM2 (rs574344 and rs12024479), GSTM3 (rs1537236, rs7483, and rs10735234), GSTM4 (rs668413, rs560018, and rs506008), and GSTM5 (rs929166 and rs11807) genes. Diplotypes were generated in the software Phase 3.0.2. DNA methylation was measured in over 450,000 CpG sites using the Infinium HumanMethylation450 BeadChip (Illumina 450K) in a subsample of 245 18-year olds from the Isle of Wight birth cohort. Gender, age, in utero smoke exposure, secondhand smoke exposure (SHS), and current smoking status were assessed via questionnaire; smoke exposures were validated with urine cotinine. We used linear mixed models to estimate the effect of GSTM diplotypes on lung function across time and examine interactions with tobacco smoke. Results 1,121 (77%) out of 1,456 children had information on lung function at ages 10 or 18. After adjustment for false discovery rate, one diplotype in GSTM3 had a detrimental effect on changes in FEV1 (p=0.03), and another diplotype in GSTM3 reduced FVC (p=0.02) over time. No significant interactions with smoking were identified. SHS significantly modified the relationship between diplotypes and methylation levels in one GSTM2 CpG site; however, this site did not predict lung function outcomes at age 18. Joint effects of GSTM loci and CpG sites located within these loci on adolescent lung growth were detected. Conclusions Diplotypes within GSTM2-5 genes are associated with lung function growth across adolescence, but do not appear to modify the effect of tobacco smoke exposures on adolescent lung growth. Interactions between DNA methylation and diplotypes should be taken into account to gain further understanding on lung function in adolescence.
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Affiliation(s)
- Melannie Alexander
- Division of Epidemiology, Biostatistics and Environmental Health, School of Public Health, University of Memphis, 236A Robison Hall, Memphis, TN 38152, USA.
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Coogan PF, Wise LA, O'Connor GT, Brown TA, Palmer JR, Rosenberg L. Abuse during childhood and adolescence and risk of adult-onset asthma in African American women. J Allergy Clin Immunol 2012; 131:1058-63. [PMID: 23219171 DOI: 10.1016/j.jaci.2012.10.023] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2012] [Revised: 10/16/2012] [Accepted: 10/19/2012] [Indexed: 10/27/2022]
Abstract
BACKGROUND Experiences of violence contribute to the occurrence of childhood asthma, but there is little information on the effect of early-life abuse on adult-onset asthma. OBJECTIVE We prospectively assessed the relation between physical and sexual abuse during childhood and adolescence and the incidence of adult-onset asthma in the Black Women's Health Study. METHODS We followed 28,456 women from 1995 through 2011 with biennial mailed questionnaires. Experiences of physical and sexual abuse that occurred during childhood and adolescence were obtained in 2005. Cox regression models were used to estimate incidence rate ratios (IRRs) and 95% CIs. RESULTS During 417,931 person-years of follow-up, 1,160 participants reported physician-diagnosed asthma and concurrent use of asthma medication. Compared with women who experienced no abuse during childhood or adolescence, the multivariable IRR for any childhood abuse was 1.24 (95% CI, 1.06-1.45), and for any adolescent abuse, it was 1.10 (95% CI, 0.88-1.36). The IRR was higher for childhood physical abuse (IRR, 1.29; 95% CI, 1.07-1.49) than for childhood sexual abuse (IRR, 1.15; 95% CI, 0.88-1.49). IRRs for physical and sexual abuse during adolescence were compatible with 1.0. The association between childhood abuse and asthma incidence was stronger in older compared with younger women. CONCLUSION In this large cohort of African American women, there was a positive association between adult-onset asthma and childhood physical abuse and weaker associations for childhood sexual abuse and any abuse during adolescence. Given the high prevalence of asthma and childhood abuse, this association is of public health importance.
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Affiliation(s)
- Patricia F Coogan
- Slone Epidemiology Center, Department of Medicine, Boston University School of Medicine, Boston University, Boston, MA 02215, USA.
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Neuman Å, Hohmann C, Orsini N, Pershagen G, Eller E, Kjaer HF, Gehring U, Granell R, Henderson J, Heinrich J, Lau S, Nieuwenhuijsen M, Sunyer J, Tischer C, Torrent M, Wahn U, Wijga AH, Wickman M, Keil T, Bergström A. Maternal smoking in pregnancy and asthma in preschool children: a pooled analysis of eight birth cohorts. Am J Respir Crit Care Med 2012; 186:1037-43. [PMID: 22952297 DOI: 10.1164/rccm.201203-0501oc] [Citation(s) in RCA: 163] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
RATIONALE Although epidemiological studies suggest that exposure to maternal smoking during fetal and early life increases the risk of childhood wheezing and asthma, previous studies were not able to differentiate the effects of prenatal from postnatal exposure. OBJECTIVES To assess the effect of exposure to maternal smoking only during pregnancy on wheeze and asthma among preschool-age children. METHODS A pooled analysis was performed based on individual participant data from eight European birth cohorts. Cohort-specific effects of maternal smoking during pregnancy, but not during the first year, on wheeze and asthma at 4 to 6 years of age were estimated using logistic regression and then combined using a random effects model. Adjustments were made for sex, parental education, parental asthma, birth weight, and siblings. MEASUREMENTS AND MAIN RESULTS Among the 21,600 children included in the analysis, 735 children (3.4%) were exposed to maternal smoking exclusively during pregnancy but not in the first year after birth. In the pooled analysis, maternal smoking only during pregnancy was associated with wheeze and asthma at 4 to 6 years of age, with adjusted odds ratios of 1.39 (95% confidence interval, 1.08-1.77) and 1.65 (95% confidence interval, 1.18-2.31), respectively. The likelihood to develop wheeze and asthma increased statistically significantly in a linear dose-dependent manner in relation to maternal daily cigarette consumption during the first trimester of pregnancy. CONCLUSIONS Maternal smoking during pregnancy appears to increase the risk of wheeze and asthma among children who are not exposed to maternal smoking after birth.
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Affiliation(s)
- Åsa Neuman
- Institute of Environmental Medicine, Karolinska Institutet, Box 210, SE-171 77 Stockholm, Sweden
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Substance p regulates environmental tobacco smoke-enhanced tracheal smooth muscle responsiveness in mice. J Allergy (Cairo) 2012; 2012:423612. [PMID: 22927867 PMCID: PMC3425797 DOI: 10.1155/2012/423612] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2012] [Revised: 06/05/2012] [Accepted: 07/04/2012] [Indexed: 11/17/2022] Open
Abstract
Environmental tobacco smoke (ETS) is an environmental trigger that leads to airway inflammation and airway hyperresponsiveness (AHR) in susceptible individuals and animals, but the underlying mechanism is not fully understood. Substance P (SP) release from sensory nerve fibers has been linked to AHR. The present experiments characterize the role of SP in tracheal smooth muscle on ETS-increased airway responses. The mice were exposed to either sidestream tobacco smoke (SS), a surrogate to ETS, or filtered air (FA) for 1 day or 5 consecutive days. Contractions of tracheal smooth muscle to SP and electrical field stimulation (EFS) were not significantly altered in 1 of day SS-exposed mice. However, 5 of days SS exposure significantly increased airway smooth muscle contractions to SP and EFS. Administration of CP-99994, an antagonist of the neurokinin (NK)1 receptor, attenuates the SS exposure-enhanced tracheal smooth muscle responses to EFS. Furthermore, the immunohistochemistry showed that SP nerve fibers were increased in tracheal smooth muscle after 5 of days SS exposure. These results suggest that the increased SP production may contribute to SS-enhanced smooth muscle responsiveness in mice trachea.
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Effect of secondhand smoke on asthma control among black and Latino children. J Allergy Clin Immunol 2012; 129:1478-83.e7. [PMID: 22552109 DOI: 10.1016/j.jaci.2012.03.017] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2011] [Revised: 03/05/2012] [Accepted: 03/06/2012] [Indexed: 11/20/2022]
Abstract
BACKGROUND Among patients with asthma, the clinical effect and relative contribution of maternal smoking during pregnancy (in utero smoking) and current secondhand smoke (SHS) exposure on asthma control is poorly documented, and there is a paucity of research involving minority populations. OBJECTIVES We sought to examine the association between poor asthma control and in utero smoking and current SHS exposure among Latino and black children with asthma. METHODS We performed a case-only analysis of 2 multicenter case-control studies conducted from 2008-2010 with similar protocols. We recruited 2481 Latino and black subjects with asthma (ages 8-17 years) from the mainland United States and Puerto Rico. Ordinal logistic regression was used to estimate the effect of in utero smoking and current SHS exposures on National Heart, Lung, and Blood Institute-defined asthma control. RESULTS Poor asthma control among children 8 to 17 years of age was independently associated with in utero smoking (odds ratio [OR], 1.5; 95% CI, 1.1-2.0). In utero smoking through the mother was also associated with secondary asthma outcomes, including early-onset asthma (OR, 1.7; 95% CI, 1.1-2.4), daytime symptoms (OR, 1.6; 95% CI, 1.1-2.1), and asthma-related limitation of activities (OR, 1.6; 95% CI, 1.2-2.2). CONCLUSIONS Maternal smoking while in utero is associated with poor asthma control in black and Latino subjects assessed at 8-17 years of age.
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Alder JK, Guo N, Kembou F, Parry EM, Anderson CJ, Gorgy AI, Walsh MF, Sussan T, Biswal S, Mitzner W, Tuder RM, Armanios M. Telomere length is a determinant of emphysema susceptibility. Am J Respir Crit Care Med 2011; 184:904-12. [PMID: 21757622 PMCID: PMC3208661 DOI: 10.1164/rccm.201103-0520oc] [Citation(s) in RCA: 182] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2011] [Accepted: 06/30/2011] [Indexed: 01/14/2023] Open
Abstract
RATIONALE Germline mutations in the enzyme telomerase cause telomere shortening, and have their most common clinical manifestation in age-related lung disease that manifests as idiopathic pulmonary fibrosis. Short telomeres are also a unique heritable trait that is acquired with age. OBJECTIVES We sought to understand the mechanisms by which telomerase deficiency contributes to lung disease. METHODS We studied telomerase null mice with short telomeres. MEASUREMENTS AND MAIN RESULTS Although they have no baseline histologic defects, when mice with short telomeres are exposed to chronic cigarette smoke, in contrast with controls, they develop emphysematous air space enlargement. The emphysema susceptibility did not depend on circulating cell genotype, because mice with short telomeres developed emphysema even when transplanted with wild-type bone marrow. In lung epithelium, cigarette smoke exposure caused additive DNA damage to telomere dysfunction, which limited their proliferative recovery, and coincided with a failure to down-regulate p21, a mediator of cellular senescence, and we show here, a determinant of alveolar epithelial cell cycle progression. We also report early onset of emphysema, in addition to pulmonary fibrosis, in a family with a germline deletion in the Box H domain of the RNA component of telomerase. CONCLUSIONS Our data indicate that short telomeres lower the threshold of cigarette smoke-induced damage, and implicate telomere length as a genetic susceptibility factor in emphysema, potentially contributing to its age-related onset in humans.
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Affiliation(s)
| | | | | | | | | | | | | | - Thomas Sussan
- Department of Environmental Health Sciences, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland; and
| | - Shyam Biswal
- Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, Maryland
- Department of Environmental Health Sciences, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland; and
| | - Wayne Mitzner
- Department of Environmental Health Sciences, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland; and
| | - Rubin M. Tuder
- Division of Pulmonary Sciences and Critical Care Medicine, University of Colorado Denver, Aurora, Colorado
| | - Mary Armanios
- Department of Oncology
- McKusick-Nathans Institute of Genetic Medicine, and the
- Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, Maryland
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Wu ZX, Benders KB, Hunter DD, Dey RD. Early postnatal exposure of mice to side-steam tobacco smoke increases neuropeptide Y in lung. Am J Physiol Lung Cell Mol Physiol 2011; 302:L152-9. [PMID: 22003086 DOI: 10.1152/ajplung.00071.2011] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Our recent study showed that prenatal and early postnatal exposure of mice to side-steam tobacco smoke (SS), a surrogate to environmental tobacco smoke (ETS), leads to increased airway responsiveness and sensory innervation later in life. However, the underlying mechanism initiated in early life that affects airway responses later in life remains undefined. The concomitant increase in nerve growth factor (NGF) after exposures suggests that NGF may be involved the regulation of airway innervation. Since NGF regulates sympathetic nerve responses, as well as sensory nerves, we extended previous studies by examining neuropeptide Y (NPY), a neuropeptide associated with sympathetic nerves. Different age groups of mice, postnatal day (PD) 2 and PD21, were exposed to either SS or filtered air (FA) for 10 consecutive days. The level of NPY protein in lung and the density of NPY nerve fibers in tracheal smooth muscle were significantly increased in the PD2-11SS exposure group compared with PD2-11FA exposure. At the same time, the level of NGF in lung tissue was significantly elevated in the PD2-11SS exposure groups. However, neither NPY (protein or nerves) nor NGF levels were significantly altered in PD21-30SS exposure group compared with the PD21-30FA exposure group. Furthermore, pretreatment with NGF antibody or K252a, which inhibits a key enzyme (tyrosine kinase) in the transduction pathway for NGF receptor binding, significantly diminished SS-enhanced NPY tracheal smooth muscle innervation and the increase in methacholine-induced airway resistance. These findings show that SS exposure in early life increases NPY tracheal innervation and alters pulmonary function and that these changes are mediated through the NGF.
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Affiliation(s)
- Z-X Wu
- Dept. of Neurobiology and Anatomy, PO Box 9128, Robert C. Byrd Health, Sciences Center, West Virginia Univ., Morgantown, WV 26506, USA.
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Sharkhuu T, Doerfler DL, Copeland C, Luebke RW, Gilmour MI. Effect of maternal exposure to ozone on reproductive outcome and immune, inflammatory, and allergic responses in the offspring. J Immunotoxicol 2011; 8:183-94. [PMID: 21534884 DOI: 10.3109/1547691x.2011.568978] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
There is growing concern that exposure to air pollutants during pregnancy affects health outcomes in the offspring due to alterations in the development of immune and other homeostatic processes. To assess the risks of maternal inhalation exposure to ozone (O(3)), timed pregnant BALB/c mice were exposed to different concentrations of O(3) (0, 0.4, 0.8, and 1.2 ppm) for 4 h/day for 10 days during gestation (GD9-GD18), and pulmonary inflammation and immune responses were assessed in the offspring at 6 weeks-of-age. Maternal O(3) exposure reduced the number of productive dams by 25% at the highest O(3) concentration (1.2 ppm) and decreased the rate of weight gain in the offspring. Delayed-type hypersensitivity responses to bovine serum albumin were suppressed in the female offspring by maternal exposure to the two highest concentrations of O(3), whereas humoral immune responses to sheep red blood cells were not altered in either sex. Maternal exposure to 1.2 ppm O(3) increased lactate dehydrogenase (LDH) activity in bronchoalveolar lavage fluid (BALF) of the offspring but did not affect the number of inflammatory cells or levels of total protein, IFN-γ, IL-17, and IL-4 cytokines in BALF, or CD4(+), CD8(+), CD25(+), and TCRβ(+)CD1d(+) T-cells in the spleen. Offspring born from air-exposed dams sensitized early in life (postnatal day [PND] 3) to ovalbumin (OVA) antigen and then challenged as adults developed eosinophilia, elevated levels of LDH activity and total protein in BALF, and increased pulmonary responsiveness to methacholine, compared with animals sensitized at PND42. Maternal O(3) exposure in the 1.2 ppm O(3) group decreased BALF eosinophilia and serum OVA-specific IgE in the female offspring sensitized early in life but did not affect development of allergic airway inflammation by offspring sensitized late in life. In summary, maternal exposure to O(3) affected reproductive outcome and produced modest decreases in immune function and indicators of allergic lung disease in surviving offspring.
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Affiliation(s)
- Tuya Sharkhuu
- Cardiopulmonary and Immunotoxicology Branch, Environmental Public Health Division, US Environmental Protection Agency (EPA), Research Triangle Park, NC 27711, USA
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Wang IJ, Hsieh WS, Chen CY, Fletcher T, Lien GW, Chiang HL, Chiang CF, Wu TN, Chen PC. The effect of prenatal perfluorinated chemicals exposures on pediatric atopy. ENVIRONMENTAL RESEARCH 2011; 111:785-91. [PMID: 21601844 DOI: 10.1016/j.envres.2011.04.006] [Citation(s) in RCA: 93] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2010] [Revised: 02/26/2011] [Accepted: 04/19/2011] [Indexed: 05/22/2023]
Abstract
BACKGROUND The role of perfluorinated compounds (PFCs) in the immune system and allergic diseases is not well-known. This study examined the effects of pre-natal exposure to PFCs on immunoglobulin E (IgE) levels and atopic dermatitis (AD). METHODS In Taiwan Birth Panel cohort study, newborns with cord blood and peri-natal factors (i.e. birth body weight, weeks of gestation, and type of delivery) gathered at birth were evaluated. At the age of 2 years, information on the development of AD, environmental exposures, and serum total IgE were collected. The AD and non-AD children were compared for the concentration of cord blood serum PFCs measured by Ultra-performance liquid chromatography/triple-quadrupole mass (UPLC-MS/MS). Correlations among cord blood IgE, serum total IgE at 2 years of age, and cord blood PFC levels were made. RESULTS Of 244 children who completed the follow-up and specimen collections, 43 (17.6%) developed AD. Concentrations of cord blood serum perfluorooctanoic acid (PFOA), perfluorooctane sulfonate (PFOS), perfluorononanoic acid (PFNA), and perfluorohexane sulfonic acid (PFHxS) were median (range) 1.71 (0.75-17.40), 5.50 (0.11-48.36), 2.30 (0.38-63.87), and 0.035 (0.035-0.420)ng/mL, respectively. PFOA and PFOS levels positively correlated with cord blood IgE levels (per ln-unit: β=0.134 KU/l, p=0.047 for PFOA; β=0.161 KU/l, p=0.017 for PFOS). Analyses stratified by gender revealed that PFOA and PFOS levels positively correlated with cord blood IgE levels only in boys (per ln-unit: β=0.206 KU/l, p=0.025 for PFOA; β=0.175 KU/l, p=0.053 for PFOS). When dividing cord blood serum PFCs into quartiles in the fully adjusted models, AD had no significant association with PFOS. CONCLUSIONS Pre-natal PFOA and PFOS exposures positively correlated with cord blood IgE levels.
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Affiliation(s)
- I-Jen Wang
- Department of Pediatrics, Taipei Hospital, Department of Health, Taipei, Taiwan
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McGrath-Morrow S, Malhotra D, Lauer T, Collaco JM, Mitzner W, Neptune E, Wise R, Biswal S. Exposure to neonatal cigarette smoke causes durable lung changes but does not potentiate cigarette smoke-induced chronic obstructive pulmonary disease in adult mice. Exp Lung Res 2011; 37:354-63. [PMID: 21649527 DOI: 10.3109/01902148.2011.577268] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The impact of early childhood cigarette smoke (CS) exposure on CS-induced chronic obstructive pulmonary disease (COPD) is unknown. This study was performed to evaluate the individual and combined effects of neonatal and adult CS exposure on lung structure, function, and gene expression in adult mice. To model a childhood CS exposure, neonatal C57/B6 mice were exposed to 14 days of CS (Neo CS). At 10 weeks of age, Neo CS and control mice were exposed to 4 months of CS. Pulmonary function tests, bronchoalveolar lavage, and lung morphometry were measured and gene expression profiling was performed on lung tissue. Mean chord lengths and lung volumes were increased in neonatal and/or adult CS-exposed mice. Differences in immune, cornified envelope protein, muscle, and erythrocyte genes were found in CS-exposed lung. Neonatal CS exposure caused durable structural and functional changes in the adult lung but did not potentiate CS-induced COPD changes. Cornified envelope protein gene expression was decreased in all CS-exposed mice, whereas myosin and erythrocyte gene expression was increased in mice exposed to both neonatal and adult CS, suggesting an adaptive response. Additional studies may be warranted to determine the utility of these genes as biomarkers of respiratory outcomes.
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Affiliation(s)
- Sharon McGrath-Morrow
- Division of Pediatric Pulmonary, Department of Pediatrics, Johns Hopkins School of Medicine, Baltimore, Maryland 21287-2533, USA.
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Rosa MJ, Jung KH, Perzanowski MS, Kelvin EA, Darling KW, Camann DE, Chillrud SN, Whyatt RM, Kinney PL, Perera FP, Miller RL. Prenatal exposure to polycyclic aromatic hydrocarbons, environmental tobacco smoke and asthma. Respir Med 2011; 105:869-76. [PMID: 21163637 PMCID: PMC3081952 DOI: 10.1016/j.rmed.2010.11.022] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/11/2010] [Revised: 11/17/2010] [Accepted: 11/19/2010] [Indexed: 01/25/2023]
Abstract
BACKGROUND Previously, we reported that prenatal exposures to polycyclic aromatic hydrocarbons (PAH) and postnatal environmental tobacco smoke (ETS) in combination were associated with respiratory symptoms at ages 1 and 2 years. Here, we hypothesized that children exposed to both prenatal PAH and ETS may be at greater risk of asthma and seroatopy at ages 5-6 years, after controlling for current pollution exposure. METHODS Prenatal PAH exposure was measured by personal air monitoring over 48 h. ETS exposure, respiratory symptoms and asthma at ages 5-6 years were assessed through questionnaire. Immunoglobulin (Ig) E was measured by Immunocap. RESULTS A significant interaction between prenatal PAH and prenatal (but not postnatal) ETS exposure on asthma (p < 0.05), but not IgE, was detected. Among children exposed to prenatal ETS, a positive nonsignificant association was found between prenatal PAH exposure and asthma (OR 1.96, 95% CI [0.95-4.05]). Among children without exposure to prenatal ETS, a negative nonsignificant association was found between prenatal PAH exposure and asthma (OR 0.65, 95% CI [0.41-1.01]). Prenatal PAH exposure was not associated with asthma or IgE at age 5-6 years. CONCLUSIONS Combined prenatal exposure to PAH and ETS appears to be associated with asthma but not seroatopy at age 5-6. Exposure to PAH alone does not appear associated with either asthma or seroatopy at age 5-6 years. Discerning the differential effects between ETS exposed and ETS nonexposed children requires further study.
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Affiliation(s)
- Maria José Rosa
- Division of Pulmonary, Allergy, Critical Care Medicine, Department of Medicine, Columbia University College of Physicians and Surgeons, NY 10032, USA.
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Takeda M, Miyake M, Muto T, Kamijima M, Sakamoto T. Proliferation of sensory C-fibers and subsequent neurogenic inflammation in rat airway induced by inhaled lipopolysaccharide. Neurotoxicology 2011; 32:954-62. [PMID: 21570423 DOI: 10.1016/j.neuro.2011.03.015] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2010] [Revised: 03/02/2011] [Accepted: 03/30/2011] [Indexed: 11/16/2022]
Abstract
Lipopolysaccharide (LPS) is associated with the development and exacerbation of airway inflammation. Increases in innervation of sensory C-fibers and tachykinin receptors, which mainly involve overproduction of neurotrophins such as nerve growth factor (NGF), may enhance neurogenic inflammation. Expression of NGF and its receptors in rat lungs is known to decline with age. We examined whether inhaled LPS causes proliferation of sensory C-fibers, increased expression of tachykinin receptors and subsequent enhancement of neurogenic inflammation in the airways of preweaning rats. Wistar male rats aged 2 weeks inhaled aerosolized LPS derived from Escherichia coli (0.1mg/ml) for 30 min. Evans blue dye leakage into the trachea induced by gaseous formaldehyde or intravenous capsaicin was measured as an index of tachykinin NK1 receptor-mediated vascular permeability. Expression of substance P-immunoreactive nerves, tachykinin NK1 receptors, tumor necrosis factor (TNF)-α and NGF in the trachea was also assessed immunohistochemically. Neurogenic plasma leakage in the trachea increased significantly between 7 and 21 days after LPS inhalation. Expression of TNF-α, NGF, substance P-immunoreactive nerves and tachykinin NK1 receptors was enhanced, peaking at 28 h, 7 days, 14 days and 14 days after LPS inhalation, respectively. Pretreatment with infliximab, a blocking antibody for TNF-α, almost completely abolished the airway changes seen after LPS inhalation. In conclusion, inhaled LPS increased innervation of sensory C-fibers and expression of tachykinin NK1 receptors in the airway, probably resulting in enhancement of neurogenic airway inflammation. These airway responses may be caused by overproduction of neurotrophins including NGF, mainly through a TNF-α-mediated pathway.
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Affiliation(s)
- Masanori Takeda
- Department of Pediatrics, Nagoya University Graduate School of Medicine, Tsurumai-cho 65, Showa-ku, Nagoya 466-8550, Japan
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Hunter DD, Carrell-Jacks LA, Batchelor TP, Dey RD. Role of nerve growth factor in ozone-induced neural responses in early postnatal airway development. Am J Respir Cell Mol Biol 2010; 45:359-65. [PMID: 21075861 DOI: 10.1165/rcmb.2010-0345oc] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Airway neural plasticity contributes to the process of airway remodeling in response to airway irritants. However, the mechanisms of neural remodeling in the airways during the early postnatal period, when responses to airway irritation may be most sensitive, have not been characterized. This study used a rat model to examine a possible mechanism of ozone (O(3))-induced neural hyperresponsiveness during a critical period of developmental, postnatal day (PD) 6, that may be mediated by the neurotrophin nerve growth factor (NGF), resulting in an enhanced release of inflammatory neuropeptide substance P (SP) from airway nerves. Rat pups between PD6-PD28 were killed 24 hours after exposure to O(3) (2 ppm, 3 hours) or filtered air (FA), to establish a timeline of NGF synthesis, or else they were exposed to O(3) or NGF on PD6 or PD21 and re-exposed to O(3) on PD28, and killed on PD29. Measurement endpoints included NGF mRNA in tracheal epithelial cells, NGF protein in bronchoalveolar lavage fluid, airway SP-nerve fiber density (NFD), and SP-positive airway neurons in vagal ganglia. Acute exposure to O(3) increased NGF in bronchoalveolar lavage fluid on PD10 and PD15, and mRNA expression in epithelial cells on PD6, compared with FA controls. NGF protein and mRNA expression in the O(3)-PD6/O(3)-PD28 groups were significantly higher than in the O(3)-PD21/O(3)-PD28 and O(3)-PD6/FA-PD28 groups. NGF-PD6/O(3)-PD28 increased the SP innervation of airway smooth muscle and SP-positive sensory neurons, compared with the NGF-PD21/O(3)-PD28 or NGF-PD6/FA-PD28 groups. NGF enhanced sensory innervation, which may mediate acute responses or prolong sensitivity to O(3) during early life. The model may be relevant in O(3) responses during early childhood.
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Affiliation(s)
- Dawn D Hunter
- Department of Neurobiology and Anatomy, West Virginia University, Morgantown, 26506, USA.
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Abstract
Significant strides in the understanding of the role of epigenetic regulation in asthma and allergy using both epidemiological approaches as well as experimental ones have been made. This review focuses on new research within the last 2 years. These include advances in determining how environmental agents implicated in airway disease can induce epigenetic changes, how epigenetic regulation can influence T helper cell differentiation and T regulatory cell production, and new discoveries of epigenetic regulation associated with clinical outcomes.
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Affiliation(s)
- J S Kuriakose
- Division of Pulmonary, Allergy, and Critical Care Medicine, Columbia University College of Physicians and Surgeons, 630 W. 168th Street, New York, NY 10032, USA
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Lee D, Wallis C, Wexler AS, Schelegle ES, Van Winkle LS, Plopper CG, Fanucchi MV, Kumfer B, Kennedy IM, Chan JKW. Small particles disrupt postnatal airway development. J Appl Physiol (1985) 2010; 109:1115-24. [PMID: 20634362 DOI: 10.1152/japplphysiol.00295.2010] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Increasing numbers of epidemiologic studies associate air pollution exposure in children with decreased lung function development. The objective of this study was to examine the effects of exposure to combustion-generated fine [230 and 212 nm number mean aerodynamic particle diameter (NMAD)] to ultrafine (73 nm NMAD) particles differing in elemental (EC) and organic (OC) carbon content on postnatal airway development in rats. Neonatal Sprague-Dawley rats were exposed from postnatal day 7 through 25, and lung function and airway architecture were evaluated 81 days of age. In a separate group of rats, cell proliferation was examined after a single particle exposure at 7 days of age. Early life exposure to 73 nm high OC/EC particles altered distal airway architecture and resulted in subtle changes in lung mechanics. Early life exposure to 212 nm high OC/EC particles did not alter lung architecture but did alter lung mechanics in a manner suggestive of central airway changes. In contrast, early life exposure to 230 nm low OC/EC particles did not alter lung architecture or mechanics. A single 6-h exposure to 73 nm high OC/EC particle decreased airway cell proliferation, whereas 212 nm high OC/EC particles increased it and 230 nm low OC/EC particles did not. The early life exposure to ultrafine, high OC/EC particles results in persistent alterations in distal airway architecture that is characterized by an initial decrease in airway cell proliferation.
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Affiliation(s)
- DongYoub Lee
- Department of Mechanical and Aerospace Engineering, Univ. of California, Davis, CA 95616, USA
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Hunter DD, Wu Z, Dey RD. Sensory neural responses to ozone exposure during early postnatal development in rat airways. Am J Respir Cell Mol Biol 2010; 43:750-7. [PMID: 20118220 DOI: 10.1165/rcmb.2009-0191oc] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Airway infections or irritant exposures during early postnatal periods may contribute to the onset of childhood asthma. The purpose of this study was to examine critical periods of postnatal airway development during which ozone (O(3)) exposure leads to heightened neural responses. Rats were exposed to O(3) (2 ppm) or filtered air for 1 hour on specific postnatal days (PDs) between PD1 and PD29, and killed 24 hours after exposure. In a second experiment, rats were exposed to O(3) on PD2-PD6, inside a proposed critical period of development, or on PD19-PD23, outside the critical period. Both groups were re-exposed to O(3) on PD28, and killed 24 hours later. Airways were removed, fixed, and prepared for substance P (SP) immunocytochemistry. SP nerve fiber density (NFD) in control extrapulmonary (EXP) epithelium/lamina propria (EPLP) increased threefold, from 1% to 3.3% from PD1-PD3 through PD13-PD15, and maintained through PD29. Upon O(3) exposure, SP-NFD in EXP-smooth muscle (SM) and intrapulmonary (INT)-SM increased at least twofold at PD1-PD3 through PD13-PD15 in comparison to air exposure. No change was observed at PD21-PD22 or PD28-PD29. In critical period studies, SP-NFD in the INT-SM and EXP-SM of the PD2-PD6 O(3) group re-exposed to O(3) on PD28 was significantly higher than that of the group exposed at PD19-PD23 and re-exposed at PD28. These findings suggest that O(3)-mediated changes in sensory innervation of SM are more responsive during earlier postnatal development. Enhanced responsiveness of airway sensory nerves may be a contributing mechanism of increased susceptibility to environmental exposures observed in human infants and children.
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Affiliation(s)
- Dawn D Hunter
- Department of Neurobiology and Anatomy, West Virginia University, Morgantown, WV 26506, USA.
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