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Yang M, Chen Y, Huang X, Shen F, Meng Y. Lysine demethylase KDM3A alleviates hyperoxia-induced bronchopulmonary dysplasia in mice by promoting ETS1 expression. Exp Cell Res 2024; 435:113945. [PMID: 38286256 DOI: 10.1016/j.yexcr.2024.113945] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Revised: 01/15/2024] [Accepted: 01/21/2024] [Indexed: 01/31/2024]
Abstract
Bronchopulmonary dysplasia (BPD) is the most common chronic lung disease among neonates, with increasing morbidity and mortality. This study aims to investigate the effect and mechanism of lysine demethylase 3A (KDM3A) on hyperoxia-induced BPD. Hyperoxia-induced BPD mouse and alveolar epithelial cell models were constructed. The effects of hyperoxia on lung development were evaluated by histological and morphological analysis. The levels of KDM3A, E26 transformation specific-1 (ETS1), H3 lysine 9 dimethylation (H3K9me2), and endoplasmic reticulum (ER) stress-related indexes were quantified by RT-qPCR, Western blot, and IF staining. Cell apoptosis was assessed by flow cytometry and TUNEL staining. Transfection of oe-ETS1, oe-KDM3A, and sh-ETS1 was applied in hyperoxia-induced alveolar epithelial cells to explore the mechanism of the KDM3A/ETS1 axis in hyperoxia-induced apoptosis. KDM3A inhibitor IOX1 was applied to validate the in vivo effect of KDM3A in hyperoxia-induced BPD mice. The results displayed that hyperoxia-induced BPD mice showed reduced body weight, severe destruction of alveolar structure, decreased radial alveolar count (RAC), and increased mean linear intercept (MLI) and mean alveolar diameter (MAD). Further, hyperoxia induction down-regulated ETS1 expression, raised ER stress levels, and increased apoptosis rate in BPD mice and alveolar epithelial cells. However, transfection of oe-ETS1 improved the above changes in hyperoxia-induced alveolar epithelial cells. Moreover, transfection of oe-KDM3A up-regulated ETS1 expression, down-regulated H3K9me2 expression, inhibited ER stress, and reduced apoptosis rate in hyperoxia-induced alveolar epithelial cells. In addition, transfection of sh-ETS1 reversed the inhibitory effect of KDM3A on hyperoxia-induced apoptosis by regulating ER stress. In vivo experiments, KDM3A inhibitor IOX1 intervention further aggravated BPD in newborn mice. In a word, KDM3A alleviated hyperoxia-induced BPD in mice by promoting ETS1 expression.
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Affiliation(s)
- Min Yang
- Respiratory Department, Hunan Children's Hospital, Changsha, 410007, China.
| | - Yanping Chen
- Respiratory Department, Hunan Children's Hospital, Changsha, 410007, China
| | | | - Fang Shen
- Research Institute of Children, Hunan Children's Hospital, Changsha, 410007, China
| | - Yanni Meng
- Respiratory Department, Hunan Children's Hospital, Changsha, 410007, China
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2
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McGraw MD, Yee M, Kim SY, Dylag AM, Lawrence BP, O'Reilly MA. Diacetyl inhalation impairs airway epithelial repair in mice infected with influenza A virus. Am J Physiol Lung Cell Mol Physiol 2022; 323:L578-L592. [PMID: 36068185 PMCID: PMC9639765 DOI: 10.1152/ajplung.00124.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Revised: 08/12/2022] [Accepted: 08/29/2022] [Indexed: 01/11/2023] Open
Abstract
Bronchiolitis obliterans (BO) is a debilitating disease of the small airways that can develop following exposure to toxic chemicals as well as respiratory tract infections. BO development is strongly associated with diacetyl (DA) inhalation exposures at occupationally relevant concentrations or severe influenza A viral (IAV) infections. However, it remains unclear whether lower dose exposures or more mild IAV infections can result in similar pathology. In the current work, we combined these two common environmental exposures, DA and IAV, to test whether shorter DA exposures followed by sublethal IAV infection would result in similar airways disease. Adult mice exposed to DA vapors 1 h/day for 5 consecutive days followed by infection with the airway-tropic IAV H3N2 (HKx31) resulted in increased mortality, increased bronchoalveolar lavage (BAL) neutrophil percentage, mixed obstruction and restriction by lung function, and subsequent airway remodeling. Exposure to DA or IAV alone failed to result in significant pathology, whereas mice exposed to DA + IAV showed increased α-smooth muscle actin (αSMA) and epithelial cells coexpressing the basal cell marker keratin 5 (KRT5) with the club cell marker SCGB1A1. To test whether DA exposure impairs epithelial repair after IAV infection, mice were infected first with IAV and then exposed to DA during airway epithelial repair. Mice exposed to IAV + DA developed similar airway remodeling with increased subepithelial αSMA and epithelial cells coexpressing KRT5 and SCGB1A1. Our findings reveal an underappreciated concept that common environmental insults while seemingly harmless by themselves can have catastrophic implications on lung function and long-term respiratory health when combined.
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Affiliation(s)
- Matthew D McGraw
- Department of Pediatrics, University of Rochester Medical Center, Rochester, New York
- Department of Environmental Medicine, University of Rochester Medical Center, Rochester, New York
| | - Min Yee
- Department of Pediatrics, University of Rochester Medical Center, Rochester, New York
| | - So-Young Kim
- Department of Pediatrics, University of Rochester Medical Center, Rochester, New York
| | - Andrew M Dylag
- Department of Pediatrics, University of Rochester Medical Center, Rochester, New York
| | - B Paige Lawrence
- Department of Environmental Medicine, University of Rochester Medical Center, Rochester, New York
| | - Michael A O'Reilly
- Department of Pediatrics, University of Rochester Medical Center, Rochester, New York
- Department of Environmental Medicine, University of Rochester Medical Center, Rochester, New York
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Age-dependent alveolar epithelial plasticity orchestrates lung homeostasis and regeneration. Cell Stem Cell 2021; 28:1775-1789.e5. [PMID: 33974915 PMCID: PMC8500919 DOI: 10.1016/j.stem.2021.04.026] [Citation(s) in RCA: 54] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Revised: 03/11/2021] [Accepted: 04/21/2021] [Indexed: 02/07/2023]
Abstract
Regeneration of the architecturally complex alveolar niche of the lung requires precise temporal and spatial control of epithelial cell behavior. Injury can lead to a permanent reduction in gas exchange surface area and respiratory function. Using mouse models, we show that alveolar type 1 (AT1) cell plasticity is a major and unappreciated mechanism that drives regeneration, beginning in the early postnatal period during alveolar maturation. Upon acute neonatal lung injury, AT1 cells reprogram into alveolar type 2 (AT2) cells, promoting alveolar regeneration. In contrast, the ability of AT2 cells to regenerate AT1 cells is restricted to the mature lung. Unbiased genomic assessment reveals that this previously unappreciated level of plasticity is governed by the preferential activity of Hippo signaling in the AT1 cell lineage. Thus, cellular plasticity is a temporally acquired trait of the alveolar epithelium and presents an alternative mode of tissue regeneration in the postnatal lung.
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Yue L, Shi Y, Su X, Ouyang L, Wang G, Ye T. Matrix metalloproteinases inhibitors in idiopathic pulmonary fibrosis: Medicinal chemistry perspectives. Eur J Med Chem 2021; 224:113714. [PMID: 34315043 DOI: 10.1016/j.ejmech.2021.113714] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 07/06/2021] [Accepted: 07/06/2021] [Indexed: 02/05/2023]
Abstract
Idiopathic pulmonary fibrosis (IPF) is a lethal disease with limited therapeutic options and a particularly poor prognosis. Matrix metalloproteinases (MMPs), promising targets for the treatment of IPF, have been identified as playing a pivotal role in IPF. Although the pathological processes of MMPs and IPF have been verified, there are no MMP inhibitors for the treatment of IPF in the clinic. In this review, we will present the latest developments in MMP inhibitors, including pharmacophores, binding modes, selectivity and optimization strategies. In addition, we will also discuss the future development direction of MMP inhibitors based on emerging tools and techniques.
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Affiliation(s)
- Lin Yue
- Sichuan University-University of Oxford Huaxi Joint Centre for Gastrointestinal Cancer, Department of Gastroenterology and Hepatology, Frontiers Science Center for Disease-Related Molecular Network, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, 610041, China
| | - Yaojie Shi
- Sichuan University-University of Oxford Huaxi Joint Centre for Gastrointestinal Cancer, Department of Gastroenterology and Hepatology, Frontiers Science Center for Disease-Related Molecular Network, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, 610041, China
| | - Xingping Su
- Sichuan University-University of Oxford Huaxi Joint Centre for Gastrointestinal Cancer, Department of Gastroenterology and Hepatology, Frontiers Science Center for Disease-Related Molecular Network, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, 610041, China
| | - Liang Ouyang
- Sichuan University-University of Oxford Huaxi Joint Centre for Gastrointestinal Cancer, Department of Gastroenterology and Hepatology, Frontiers Science Center for Disease-Related Molecular Network, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, 610041, China
| | - Guan Wang
- Sichuan University-University of Oxford Huaxi Joint Centre for Gastrointestinal Cancer, Department of Gastroenterology and Hepatology, Frontiers Science Center for Disease-Related Molecular Network, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, 610041, China; Innovation Center of Nursing Research, Nursing Key Laboratory of Sichuan Province, West China Hospital, Sichuan University, Chengdu, 610041, China.
| | - Tinghong Ye
- Sichuan University-University of Oxford Huaxi Joint Centre for Gastrointestinal Cancer, Department of Gastroenterology and Hepatology, Frontiers Science Center for Disease-Related Molecular Network, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, 610041, China.
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5
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Sucre J, Haist L, Bolton CE, Hilgendorff A. Early Changes and Indicators Characterizing Lung Aging in Neonatal Chronic Lung Disease. Front Med (Lausanne) 2021; 8:665152. [PMID: 34136503 PMCID: PMC8200413 DOI: 10.3389/fmed.2021.665152] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2021] [Accepted: 05/04/2021] [Indexed: 12/16/2022] Open
Abstract
Infants suffering from neonatal chronic lung disease, i.e., bronchopulmonary dysplasia, are facing long-term consequences determined by individual genetic background, presence of infections, and postnatal treatment strategies such as mechanical ventilation and oxygen toxicity. The adverse effects provoked by these measures include inflammatory processes, oxidative stress, altered growth factor signaling, and remodeling of the extracellular matrix. Both, acute and long-term consequences are determined by the capacity of the immature lung to respond to the challenges outlined above. The subsequent impairment of lung growth translates into an altered trajectory of lung function later in life. Here, knowledge about second and third hit events provoked through environmental insults are of specific importance when advocating lifestyle recommendations to this patient population. A profound exchange between the different health care professionals involved is urgently needed and needs to consider disease origin while future monitoring and treatment strategies are developed.
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Affiliation(s)
- Jennifer Sucre
- Mildred Stahlman Division of Neonatology, Department of Pediatrics, Vanderbilt University, Nashville, TN, United States
| | - Lena Haist
- Institute for Lung Biology and Disease and Comprehensive Pneumology Center With the CPC-M bioArchive, Helmholtz Center Munich, Member of the German Center for Lung Research (DZL), Munich, Germany.,Center for Comprehensive Developmental Care (CDeCLMU), University Hospital Ludwig-Maximilian University, Munich, Germany
| | - Charlotte E Bolton
- Division of Respiratory Medicine, NIHR Nottingham Biomedical Research Centre, School of Medicine, University of Nottingham, City Hospital NUH Campus, Nottingham, United Kingdom
| | - Anne Hilgendorff
- Institute for Lung Biology and Disease and Comprehensive Pneumology Center With the CPC-M bioArchive, Helmholtz Center Munich, Member of the German Center for Lung Research (DZL), Munich, Germany.,Center for Comprehensive Developmental Care (CDeCLMU), University Hospital Ludwig-Maximilian University, Munich, Germany
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6
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Matrix metalloproteinase: An upcoming therapeutic approach for idiopathic pulmonary fibrosis. Pharmacol Res 2020; 152:104591. [PMID: 31837390 DOI: 10.1016/j.phrs.2019.104591] [Citation(s) in RCA: 67] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Revised: 12/04/2019] [Accepted: 12/06/2019] [Indexed: 01/26/2023]
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Yee M, Cohen ED, Domm W, Porter GA, McDavid AN, O’Reilly MA. Neonatal hyperoxia depletes pulmonary vein cardiomyocytes in adult mice via mitochondrial oxidation. Am J Physiol Lung Cell Mol Physiol 2018; 314:L846-L859. [PMID: 29345197 PMCID: PMC6008126 DOI: 10.1152/ajplung.00409.2017] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Supplemental oxygen given to preterm infants has been associated with permanently altering postnatal lung development. Now that these individuals are reaching adulthood, there is growing concern that early life oxygen exposure may also promote cardiovascular disease through poorly understood mechanisms. We previously reported that adult mice exposed to 100% oxygen between postnatal days 0 and 4 develop pulmonary hypertension, defined pathologically by capillary rarefaction, dilation of arterioles and veins, cardiac failure, and a reduced lifespan. Here, Affymetrix Gene Arrays are used to identify early transcriptional changes that take place in the lung before pulmonary capillary rarefaction. We discovered neonatal hyperoxia reduced expression of cardiac muscle genes, including those involved in contraction, calcium signaling, mitochondrial respiration, and vasodilation. Quantitative RT-PCR, immunohistochemistry, and genetic lineage mapping using Myh6CreER; Rosa26RmT/mG mice revealed this reflected loss of pulmonary vein cardiomyocytes. The greatest loss of cadiomyocytes was seen within the lung followed by a graded loss beginning at the hilum and extending into the left atrium. Loss of these cells was seen by 2 wk of age in mice exposed to ≥80% oxygen and was attributed, in part, to reduced proliferation. Administering mitoTEMPO, a scavenger of mitochondrial superoxide during neonatal hyperoxia prevented loss of these cells. Since pulmonary vein cardiomyocytes help pump oxygen-rich blood out of the lung, their early loss following neonatal hyperoxia may contribute to cardiovascular disease seen in these mice, and perhaps in people who were born preterm.
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Affiliation(s)
- Min Yee
- 1Department of Pediatrics, School of Medicine and Dentistry, The University of Rochester, Rochester, New York
| | - Ethan David Cohen
- 2Department of Medicine, School of Medicine and Dentistry, The University of Rochester, Rochester, New York
| | - William Domm
- 1Department of Pediatrics, School of Medicine and Dentistry, The University of Rochester, Rochester, New York
| | - George A. Porter
- 1Department of Pediatrics, School of Medicine and Dentistry, The University of Rochester, Rochester, New York
| | - Andrew N. McDavid
- 3Biostatistics and Computational Biology, School of Medicine and Dentistry, The University of Rochester, Rochester, New York
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8
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Cox AM, Gao Y, Perl AKT, Tepper RS, Ahlfeld SK. Cumulative effects of neonatal hyperoxia on murine alveolar structure and function. Pediatr Pulmonol 2017; 52:616-624. [PMID: 28186703 PMCID: PMC5621136 DOI: 10.1002/ppul.23654] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/12/2016] [Revised: 11/07/2016] [Accepted: 11/23/2016] [Indexed: 12/23/2022]
Abstract
BACKGROUND Bronchopulmonary dysplasia (BPD) results from alveolar simplification and abnormal development of alveolar and capillary structure. Survivors of BPD display persistent deficits in airflow and membrane and vascular components of alveolar gas diffusion. Despite being the defining feature of BPD, various neonatal hyperoxia models of BPD have not routinely assessed pulmonary gas diffusion. METHODS To simulate the most commonly-utilized neonatal hyperoxia models, we exposed neonatal mice to room air or ≥90% hyperoxia during key stages of distal lung development: through the first 4 (saccular), 7 (early alveolar), or 14 (bulk alveolar) postnatal days, followed by a period of recovery in room air until 8 weeks of age when alveolar septation is essentially complete. We systematically assessed and correlated the effects of neonatal hyperoxia on the degree of alveolar-capillary structural and functional impairment. We hypothesized that the degree of alveolar-capillary simplification would correlate strongly with worsening diffusion impairment. RESULTS Neonatal hyperoxia exposure, of any duration, resulted in alveolar simplification and impaired pulmonary gas diffusion. Mean Linear Intercept increased in proportion to the length of hyperoxia exposure while alveolar and total lung volume increased markedly only with prolonged exposure. Surprisingly, despite having a similar effect on alveolar surface area, only prolonged hyperoxia for 14 days resulted in reduced pulmonary microvascular volume. Estimates of alveolar and capillary structure, in general, correlated poorly with assessment of gas diffusion. CONCLUSION Our results help define the physiological and structural consequences of commonly-employed neonatal hyperoxia models of BPD and inform their clinical utility. Pediatr Pulmonol. 2017;52:616-624. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Angela M. Cox
- Program in Developmental Biology and Neonatal Medicine, Herman B Wells Center for Pediatric Research, Indianapolis, Indiana
- Division of Neonatology, James Whitcomb Riley Hospital for Children, Indiana University School of Medicine, Indianapolis, Indiana
| | - Yong Gao
- Program in Developmental Biology and Neonatal Medicine, Herman B Wells Center for Pediatric Research, Indianapolis, Indiana
- Program in Pulmonary Inflammation, Asthma and Allergic Diseases, Herman B Wells Center for Pediatric Research, Indianapolis, Indiana
| | - Anne-Karina T. Perl
- Division of Neonatology, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio
- Division of Pulmonary Biology, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio
| | - Robert S. Tepper
- Program in Pulmonary Inflammation, Asthma and Allergic Diseases, Herman B Wells Center for Pediatric Research, Indianapolis, Indiana
- Division of Pulmonary Medicine, Department of Pediatrics, James Whitcomb Riley Hospital for Children, Indiana University School of Medicine, Indianapolis, Indiana
| | - Shawn K. Ahlfeld
- Division of Neonatology, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio
- Division of Pulmonary Biology, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio
- Correspondence to: Shawn K. Ahlfeld, MD, Cincinnati Children’s Hospital Medical Center, 3333 Burnet Ave, MLC 7009, Cincinnati, OH 45229.
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9
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Hibbs AM, Muhlebach MS. Infection and Inflammation: Catalysts of Pulmonary Morbidity in Bronchopulmonary Dysplasia. RESPIRATORY OUTCOMES IN PRETERM INFANTS 2017. [PMCID: PMC7121702 DOI: 10.1007/978-3-319-48835-6_13] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Anna Maria Hibbs
- Department of Pediatrics, Case Western Reserve University, Cleveland, Ohio USA
| | - Marianne S. Muhlebach
- Department of Pediatrics, University of North Carolina Chapel Hill, Chapel Hill, North Carolina USA
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10
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Xiong Z, Zhou X, Yue SJ. [Methods for establishing animal model of bronchopulmonary dysplasia and their evaluation]. ZHONGGUO DANG DAI ER KE ZA ZHI = CHINESE JOURNAL OF CONTEMPORARY PEDIATRICS 2017; 19:121-125. [PMID: 28100335 PMCID: PMC7390119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 07/14/2016] [Accepted: 08/23/2016] [Indexed: 08/01/2024]
Abstract
With the development of treatment, the survival rate of premature infants has significantly increased, especially extremely premature infants and very low birth weight infants. This has led to an increase in incidence of bronchopulmonary dysplasia (BPD) year by year. BPD has been one of the most common respiratory system diseases in premature infants, especially the small premature infants. Arrested alveolar development is an important cause of BPD. Therefore, the mechanism of arrested alveolar development and the intervention measures for promoting alveolar development are the focuses of research on BPD. Selecting the appropriate animal model of BPD is the key to obtaining meaningful results in the basic research on BPD. Based on above, several common methods for establishing an animal model of BPD and the corresponding changes in pathophysiology are summarized and evaluated in order to provide a reference for selecting the appropriate animal model in studies on the pathogenesis, pathophysiology, and prevention and control strategies of BPD.
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Affiliation(s)
- Zeng Xiong
- Department of Radiology, Xiangya Hospital, Central South University, Changsha 410008, China.
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11
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Xiong Z, Zhou X, Yue SJ. [Methods for establishing animal model of bronchopulmonary dysplasia and their evaluation]. ZHONGGUO DANG DAI ER KE ZA ZHI = CHINESE JOURNAL OF CONTEMPORARY PEDIATRICS 2017; 19:121-125. [PMID: 28100335 PMCID: PMC7390119 DOI: 10.7499/j.issn.1008-8830.2017.01.020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 07/14/2016] [Accepted: 08/23/2016] [Indexed: 06/06/2023]
Abstract
With the development of treatment, the survival rate of premature infants has significantly increased, especially extremely premature infants and very low birth weight infants. This has led to an increase in incidence of bronchopulmonary dysplasia (BPD) year by year. BPD has been one of the most common respiratory system diseases in premature infants, especially the small premature infants. Arrested alveolar development is an important cause of BPD. Therefore, the mechanism of arrested alveolar development and the intervention measures for promoting alveolar development are the focuses of research on BPD. Selecting the appropriate animal model of BPD is the key to obtaining meaningful results in the basic research on BPD. Based on above, several common methods for establishing an animal model of BPD and the corresponding changes in pathophysiology are summarized and evaluated in order to provide a reference for selecting the appropriate animal model in studies on the pathogenesis, pathophysiology, and prevention and control strategies of BPD.
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Affiliation(s)
- Zeng Xiong
- Department of Radiology, Xiangya Hospital, Central South University, Changsha 410008, China.
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12
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Namba F, Ogawa R, Ito M, Watanabe T, Dennery PA, Tamura M. Sex-related differences in long-term pulmonary outcomes of neonatal hyperoxia in mice. Exp Lung Res 2016; 42:57-65. [DOI: 10.3109/01902148.2016.1141264] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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Balany J, Bhandari V. Understanding the Impact of Infection, Inflammation, and Their Persistence in the Pathogenesis of Bronchopulmonary Dysplasia. Front Med (Lausanne) 2015; 2:90. [PMID: 26734611 PMCID: PMC4685088 DOI: 10.3389/fmed.2015.00090] [Citation(s) in RCA: 111] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2015] [Accepted: 12/03/2015] [Indexed: 12/11/2022] Open
Abstract
The concerted interaction of genetic and environmental factors acts on the preterm human immature lung with inflammation being the common denominator leading to the multifactorial origin of the most common chronic lung disease in infants – bronchopulmonary dysplasia (BPD). Adverse perinatal exposure to infection/inflammation with added insults like invasive mecha nical ventilation, exposure to hyperoxia, and sepsis causes persistent immune dysregulation. In this review article, we have attempted to analyze and consolidate current knowledge about the role played by persistent prenatal and postnatal inflammation in the pathogenesis of BPD. While some parameters of the early inflammatory response (neutrophils, cytokines, etc.) may not be detectable after days to weeks of exposure to noxious stimuli, they have already initiated the signaling pathways of the inflammatory process/immune cascade and have affected permanent defects structurally and functionally in the BPD lungs. Hence, translational research aimed at prevention/amelioration of BPD needs to focus on dampening the inflammatory response at an early stage to prevent the cascade of events leading to lung injury with impaired healing resulting in the pathologic pulmonary phenotype of alveolar simplification and dysregulated vascularization characteristic of BPD.
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Affiliation(s)
- Jherna Balany
- Section of Neonatology, Department of Pediatrics, St. Christopher's Hospital for Children, Drexel University College of Medicine , Philadelphia, PA , USA
| | - Vineet Bhandari
- Section of Neonatology, Department of Pediatrics, St. Christopher's Hospital for Children, Drexel University College of Medicine , Philadelphia, PA , USA
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14
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Bolton CE, Bush A, Hurst JR, Kotecha S, McGarvey L. Republished: Lung consequences in adults born prematurely. Postgrad Med J 2015; 91:712-8. [DOI: 10.1136/postgradmedj-2014-206590rep] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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15
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Silva DMG, Nardiello C, Pozarska A, Morty RE. Recent advances in the mechanisms of lung alveolarization and the pathogenesis of bronchopulmonary dysplasia. Am J Physiol Lung Cell Mol Physiol 2015; 309:L1239-72. [PMID: 26361876 DOI: 10.1152/ajplung.00268.2015] [Citation(s) in RCA: 114] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Accepted: 09/09/2015] [Indexed: 02/08/2023] Open
Abstract
Alveolarization is the process by which the alveoli, the principal gas exchange units of the lung, are formed. Along with the maturation of the pulmonary vasculature, alveolarization is the objective of late lung development. The terminal airspaces that were formed during early lung development are divided by the process of secondary septation, progressively generating an increasing number of alveoli that are of smaller size, which substantially increases the surface area over which gas exchange can take place. Disturbances to alveolarization occur in bronchopulmonary dysplasia (BPD), which can be complicated by perturbations to the pulmonary vasculature that are associated with the development of pulmonary hypertension. Disturbances to lung development may also occur in persistent pulmonary hypertension of the newborn in term newborn infants, as well as in patients with congenital diaphragmatic hernia. These disturbances can lead to the formation of lungs with fewer and larger alveoli and a dysmorphic pulmonary vasculature. Consequently, affected lungs exhibit a reduced capacity for gas exchange, with important implications for morbidity and mortality in the immediate postnatal period and respiratory health consequences that may persist into adulthood. It is the objective of this Perspectives article to update the reader about recent developments in our understanding of the molecular mechanisms of alveolarization and the pathogenesis of BPD.
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Affiliation(s)
- Diogo M G Silva
- Department of Internal Medicine (Pulmonology), University of Giessen and Marburg Lung Center (UGMLC), Member of the German Center for Lung Research (DZL), Giessen, Germany; Department of Lung Development and Remodelling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Claudio Nardiello
- Department of Internal Medicine (Pulmonology), University of Giessen and Marburg Lung Center (UGMLC), Member of the German Center for Lung Research (DZL), Giessen, Germany; Department of Lung Development and Remodelling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Agnieszka Pozarska
- Department of Internal Medicine (Pulmonology), University of Giessen and Marburg Lung Center (UGMLC), Member of the German Center for Lung Research (DZL), Giessen, Germany; Department of Lung Development and Remodelling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - Rory E Morty
- Department of Internal Medicine (Pulmonology), University of Giessen and Marburg Lung Center (UGMLC), Member of the German Center for Lung Research (DZL), Giessen, Germany; Department of Lung Development and Remodelling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
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16
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Domm W, Misra RS, O'Reilly MA. Affect of Early Life Oxygen Exposure on Proper Lung Development and Response to Respiratory Viral Infections. Front Med (Lausanne) 2015; 2:55. [PMID: 26322310 PMCID: PMC4530667 DOI: 10.3389/fmed.2015.00055] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Accepted: 07/27/2015] [Indexed: 12/22/2022] Open
Abstract
Children born preterm often exhibit reduced lung function and increased severity of response to respiratory viruses, suggesting that premature birth has compromised proper development of the respiratory epithelium and innate immune defenses. Increasing evidence suggests that premature birth promotes aberrant lung development likely due to the neonatal oxygen transition occurring before pulmonary development has matured. Given that preterm infants are born at a point of time where their immune system is also still developing, early life oxygen exposure may also be disrupting proper development of innate immunity. Here, we review current literature in hopes of stimulating research that enhances understanding of how the oxygen environment at birth influences lung development and host defense. This knowledge may help identify those children at risk for disease and ideally culminate in the development of novel therapies that improve their health.
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Affiliation(s)
- William Domm
- Department of Pediatrics, School of Medicine and Dentistry, The University of Rochester , Rochester, NY , USA ; Department of Environmental Medicine, School of Medicine and Dentistry, The University of Rochester , Rochester, NY , USA
| | - Ravi S Misra
- Department of Pediatrics, School of Medicine and Dentistry, The University of Rochester , Rochester, NY , USA
| | - Michael A O'Reilly
- Department of Pediatrics, School of Medicine and Dentistry, The University of Rochester , Rochester, NY , USA ; Department of Environmental Medicine, School of Medicine and Dentistry, The University of Rochester , Rochester, NY , USA
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Bolton CE, Bush A, Hurst JR, Kotecha S, McGarvey L. Lung consequences in adults born prematurely. Thorax 2015; 70:574-80. [DOI: 10.1136/thoraxjnl-2014-206590] [Citation(s) in RCA: 81] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2014] [Accepted: 03/06/2015] [Indexed: 11/04/2022]
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Varechova S, Demoulin B, Leblanc AL, Coutier L, Ioan I, Bonabel C, Schweitzer C, Marchal F. Neonatal hyperoxia up regulates cough reflex in young rabbits. Respir Physiol Neurobiol 2015; 208:51-6. [DOI: 10.1016/j.resp.2015.01.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2014] [Revised: 12/09/2014] [Accepted: 01/02/2015] [Indexed: 12/24/2022]
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Maduekwe ET, Buczynski BW, Yee M, Rangasamy T, Stevens TP, Lawrence BP, O'Reilly MA. Cumulative neonatal oxygen exposure predicts response of adult mice infected with influenza A virus. Pediatr Pulmonol 2015; 50:222-230. [PMID: 24850805 PMCID: PMC4334747 DOI: 10.1002/ppul.23063] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/01/2013] [Accepted: 03/31/2014] [Indexed: 11/05/2022]
Abstract
An acceptable level of oxygen exposure in preterm infants that maximizes efficacy and minimizes harm has yet to be determined. Quantifying oxygen exposure as an area-under-the curve (OAUC ) has been predictive of later respiratory symptoms among former low birth weight infants. Here, we test the hypothesis that quantifying OAUC in newborn mice can predict their risk for altered lung development and respiratory viral infections as adults. Newborn mice were exposed to room air or a FiO2 of 100% oxygen for 4 days, 60% oxygen for 8 days, or 40% oxygen for 16 days (same cumulative dose of excess oxygen). At 8 weeks of age, mice were infected intranasally with a non-lethal dose of influenza A virus. Adult mice exposed to 100% oxygen for 4 days or 60% oxygen for 8 days exhibited alveolar simplification and altered elastin deposition compared to siblings birthed into room air, as well as increased inflammation and fibrotic lung disease following viral infection. These changes were not observed in mice exposed to 40% oxygen for 16 days. Our findings in mice support the concept that quantifying OAUC over a currently unspecified threshold can predict human risk for respiratory morbidity later in life. Pediatr Pulmonol. 2015; 50:222-230. © 2014 Wiley Periodicals, Inc.
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Affiliation(s)
- Echezona T. Maduekwe
- Department of Pediatrics, School of Medicine and Dentistry, The University of Rochester, Rochester NY 14642
| | - Bradley W. Buczynski
- Department of Environmental Medicine, School of Medicine and Dentistry, The University of Rochester, Rochester NY 14642
| | - Min Yee
- Department of Pediatrics, School of Medicine and Dentistry, The University of Rochester, Rochester NY 14642
| | - Tiruamalai Rangasamy
- Department of Medicine, School of Medicine and Dentistry, The University of Rochester, Rochester NY 14642
| | - Timothy P. Stevens
- Department of Pediatrics, School of Medicine and Dentistry, The University of Rochester, Rochester NY 14642
| | - B. Paige Lawrence
- Department of Environmental Medicine, School of Medicine and Dentistry, The University of Rochester, Rochester NY 14642
| | - Michael A. O'Reilly
- Department of Pediatrics, School of Medicine and Dentistry, The University of Rochester, Rochester NY 14642
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20
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Hilgendorff A, O'Reilly MA. Bronchopulmonary dysplasia early changes leading to long-term consequences. Front Med (Lausanne) 2015; 2:2. [PMID: 25729750 PMCID: PMC4325927 DOI: 10.3389/fmed.2015.00002] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2014] [Accepted: 01/05/2015] [Indexed: 12/05/2022] Open
Abstract
Neonatal chronic lung disease, i.e., bronchopulmonary dysplasia, is characterized by impaired pulmonary development resulting from the impact of different risk factors including infections, hyperoxia, and mechanical ventilation on the immature lung. Remodeling of the extracellular matrix, apoptosis as well as altered growth factor signaling characterize the disease. The immediate consequences of these early insults have been studied in different animal models supported by results from in vitro approaches leading to the successful application of some findings to the clinical setting in the past. Nonetheless, existing information about long-term consequences of the identified early and most likely sustained changes to the developing lung is limited. Interesting results point towards a tremendous impact of these early injuries on the pulmonary repair capacity as well as aging related processes in the adult lung.
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Affiliation(s)
- Anne Hilgendorff
- Comprehensive Pneumology Center, Helmholtz Zentrum München, Member of the German Center for Lung Research (DZL) , Munich , Germany ; Neonatology, Perinatal Center Grosshadern, Dr. von Hauner Children's Hospital, Ludwig-Maximilians University , Munich , Germany
| | - Michael A O'Reilly
- Department of Pediatrics, School of Medicine and Dentistry, The University of Rochester , Rochester, NY , USA
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21
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Reilly EC, Martin KC, Jin GB, Yee M, O'Reilly MA, Lawrence BP. Neonatal hyperoxia leads to persistent alterations in NK responses to influenza A virus infection. Am J Physiol Lung Cell Mol Physiol 2015; 308:L76-85. [PMID: 25381024 PMCID: PMC4281699 DOI: 10.1152/ajplung.00233.2014] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2014] [Accepted: 11/02/2014] [Indexed: 02/06/2023] Open
Abstract
Respiratory distress in preterm or low birth weight infants is often treated with supplemental oxygen. However, this therapy can disrupt normal lung development and architecture and alter responses to respiratory insults. Similarly, exposure of newborn mice to 100% oxygen during saccular lung development leads to permanent alveolar simplification, and upon challenge with influenza A virus, mice exhibit reduced host resistance. Natural killer (NK) cells are key players in antiviral immunity, and emerging evidence suggest they also help to maintain homeostasis in peripheral tissues, including the lung, by promoting epithelial cell regeneration via IL-22. We tested the hypothesis that adult mice exposed to hyperoxia as neonates have modified NK cell responses to infection. We report here that mice exposed to neonatal hyperoxia had fewer IL-22(+) NK cells in their lungs after influenza virus challenge and a parallel increase in IFN-γ(+) NK cells. Using reciprocal bone marrow chimeric mice, we show that exposure of either hematopoietic or nonhematopoietic cells was sufficient to increase the severity of infection and to diminish the frequency of IL-22(+) NK cells in the infected lung. Overall, our findings suggest that neonatal hyperoxia leads to long-term changes in the reparative vs. cytotoxic nature of NK cells and that this is due in part to intrinsic changes in hematopoietic cells. These differences may contribute to how oxygen alters the host response to respiratory viral infections.
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Affiliation(s)
- Emma C Reilly
- Department of Environmental Medicine, University of Rochester School of Medicine and Dentistry, Rochester, New York; and
| | - Kyle C Martin
- Department of Environmental Medicine, University of Rochester School of Medicine and Dentistry, Rochester, New York; and
| | - Guang-bi Jin
- Department of Environmental Medicine, University of Rochester School of Medicine and Dentistry, Rochester, New York; and
| | - Min Yee
- Department of Pediatrics, University of Rochester School of Medicine and Dentistry, Rochester, New York
| | - Michael A O'Reilly
- Department of Environmental Medicine, University of Rochester School of Medicine and Dentistry, Rochester, New York; and Department of Pediatrics, University of Rochester School of Medicine and Dentistry, Rochester, New York
| | - B Paige Lawrence
- Department of Environmental Medicine, University of Rochester School of Medicine and Dentistry, Rochester, New York; and
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22
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Poonyagariyagorn HK, Metzger S, Dikeman D, Mercado AL, Malinina A, Calvi C, McGrath-Morrow S, Neptune ER. Superoxide dismutase 3 dysregulation in a murine model of neonatal lung injury. Am J Respir Cell Mol Biol 2014; 51:380-90. [PMID: 24673633 DOI: 10.1165/rcmb.2013-0043oc] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Bronchopulmonary dysplasia (BPD), a common chronic respiratory disease that occurs after premature birth, is believed to be secondary to oxidative damage from hyperoxia and inflammation, which leads to impaired alveolar formation and chronic lung dysfunction. We hypothesized that extracellular superoxide dismutase (SOD)3, an antioxidant uniquely targeted to the extracellular matrix (ECM) and alveolar fluid, might have a different response (down-regulation) to hyperoxic injury and recovery in room air (RA), thereby contributing to the persistent airspace injury and inflammation. We used a murine BPD model using postnatal hyperoxia (O2) (4 or 5 d) followed by short-term recovery (14 d) in RA, which mimics the durable effects after injury during alveolar development. This was associated with significantly increased mRNA expression for antioxidant genes mediated by nuclear factor erythroid 2-related factor (Nrf2) in the O2 (n = 4) versus RA group (n = 5). SOD3, an Nrf2-independent antioxidant, was significantly reduced in the O2-exposed mice compared with RA. Immunohistochemistry revealed decreased and disrupted SOD3 deposition in the alveolar ECM of O2-exposed mice. Furthermore, this distinct hyperoxic antioxidant and injury profile was reproducible in murine lung epithelial 12 cells exposed to O2. Overexpression of SOD3 rescued the injury measures in the O2-exposed cells. We establish that reduced SOD3 expression correlates with alveolar injury measures in the recovered neonatal hyperoxic lung, and SOD3 overexpression attenuates hyperoxic injury in an alveolar epithelial cell line. Such findings suggest a candidate mechanism for the pathogenesis of BPD that may lead to targeted interventions.
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23
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Berger J, Bhandari V. Animal models of bronchopulmonary dysplasia. The term mouse models. Am J Physiol Lung Cell Mol Physiol 2014; 307:L936-47. [PMID: 25305249 DOI: 10.1152/ajplung.00159.2014] [Citation(s) in RCA: 186] [Impact Index Per Article: 18.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
The etiology of bronchopulmonary dysplasia (BPD) is multifactorial, with genetics, ante- and postnatal sepsis, invasive mechanical ventilation, and exposure to hyperoxia being well described as contributing factors. Much of what is known about the pathogenesis of BPD is derived from animal models being exposed to the environmental factors noted above. This review will briefly cover the various mouse models of BPD, focusing mainly on the hyperoxia-induced lung injury models. We will also include hypoxia, hypoxia/hyperoxia, inflammation-induced, and transgenic models in room air. Attention to the stage of lung development at the timing of the initiation of the environmental insult and the duration of lung injury is critical to attempt to mimic the human disease pulmonary phenotype, both in the short term and in outcomes extending into childhood, adolescence, and adulthood. The various indexes of alveolar and vascular development as well as pulmonary function including pulmonary hypertension will be highlighted. The advantages (and limitations) of using such approaches will be discussed in the context of understanding the pathogenesis of and targeting therapeutic interventions to ameliorate human BPD.
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Affiliation(s)
- Jessica Berger
- Division of Perinatal Medicine, Department of Pediatrics, Yale University School of Medicine, New Haven, Connecticut
| | - Vineet Bhandari
- Division of Perinatal Medicine, Department of Pediatrics, Yale University School of Medicine, New Haven, Connecticut
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24
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Bhattacharya S, Zhou Z, Yee M, Chu CY, Lopez AM, Lunger VA, Solleti SK, Resseguie E, Buczynski B, Mariani TJ, O'Reilly MA. The genome-wide transcriptional response to neonatal hyperoxia identifies Ahr as a key regulator. Am J Physiol Lung Cell Mol Physiol 2014; 307:L516-23. [PMID: 25150061 DOI: 10.1152/ajplung.00200.2014] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Premature infants requiring supplemental oxygen are at increased risk for developing bronchopulmonary dysplasia (BPD). Rodent models involving neonatal exposure to excessive oxygen concentrations (hyperoxia) have helped to identify mechanisms of BPD-associated pathology. Genome-wide assessments of the effects of hyperoxia in neonatal mouse lungs could identify novel BPD-related genes and pathways. Newborn C57BL/6 mice were exposed to 100% oxygen for 10 days, and whole lung tissue RNA was used for high-throughput, sequencing-based transcriptomic analysis (RNA-Seq). Significance Analysis of Microarrays and Ingenuity Pathway Analysis were used to identify genes and pathways affected. Expression patterns for selected genes were validated by qPCR. Mechanistic relationships between genes were further tested in cultured mouse lung epithelial cells. We identified 300 genes significantly and substantially affected following acute neonatal hyperoxia. Canonical pathways dysregulated in hyperoxia lungs included nuclear factor (erythryoid-derived-2)-like 2-mediated oxidative stress signaling, p53 signaling, eNOS signaling, and aryl hydrocarbon receptor (Ahr) pathways. Cluster analysis identified Ccnd1, Cdkn1a, and Ahr as critical regulatory nodes in the response to hyperoxia, with Ahr serving as the major effector node. A mechanistic role for Ahr was assessed in lung epithelial cells, and we confirmed its ability to regulate the expression of multiple hyperoxia markers, including Cdkn1a, Pdgfrb, and A2m. We conclude that a global assessment of gene regulation in the acute neonatal hyperoxia model of BPD-like pathology has identified Ahr as one driver of gene dysregulation.
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Affiliation(s)
- Soumyaroop Bhattacharya
- Division of Neonatology, Department of Pediatrics, University of Rochester Medical Center, Rochester, New York; Pediatric Molecular and Personalized Medicine Program, Department of Pediatrics, University of Rochester Medical Center, Rochester, New York; and
| | - Zhongyang Zhou
- Division of Neonatology, Department of Pediatrics, University of Rochester Medical Center, Rochester, New York
| | - Min Yee
- Division of Neonatology, Department of Pediatrics, University of Rochester Medical Center, Rochester, New York; Perinatal and Pediatric Origins of Disease Program, Department of Pediatrics, University of Rochester Medical Center, Rochester, New York
| | - Chin-Yi Chu
- Division of Neonatology, Department of Pediatrics, University of Rochester Medical Center, Rochester, New York; Pediatric Molecular and Personalized Medicine Program, Department of Pediatrics, University of Rochester Medical Center, Rochester, New York; and
| | - Ashley M Lopez
- Division of Neonatology, Department of Pediatrics, University of Rochester Medical Center, Rochester, New York; Pediatric Molecular and Personalized Medicine Program, Department of Pediatrics, University of Rochester Medical Center, Rochester, New York; and
| | - Valerie A Lunger
- Division of Neonatology, Department of Pediatrics, University of Rochester Medical Center, Rochester, New York; Pediatric Molecular and Personalized Medicine Program, Department of Pediatrics, University of Rochester Medical Center, Rochester, New York; and
| | - Siva Kumar Solleti
- Division of Neonatology, Department of Pediatrics, University of Rochester Medical Center, Rochester, New York; Pediatric Molecular and Personalized Medicine Program, Department of Pediatrics, University of Rochester Medical Center, Rochester, New York; and
| | - Emily Resseguie
- Division of Neonatology, Department of Pediatrics, University of Rochester Medical Center, Rochester, New York; Perinatal and Pediatric Origins of Disease Program, Department of Pediatrics, University of Rochester Medical Center, Rochester, New York
| | - Bradley Buczynski
- Division of Neonatology, Department of Pediatrics, University of Rochester Medical Center, Rochester, New York; Perinatal and Pediatric Origins of Disease Program, Department of Pediatrics, University of Rochester Medical Center, Rochester, New York
| | - Thomas J Mariani
- Division of Neonatology, Department of Pediatrics, University of Rochester Medical Center, Rochester, New York; Pediatric Molecular and Personalized Medicine Program, Department of Pediatrics, University of Rochester Medical Center, Rochester, New York; and
| | - Michael A O'Reilly
- Division of Neonatology, Department of Pediatrics, University of Rochester Medical Center, Rochester, New York; Perinatal and Pediatric Origins of Disease Program, Department of Pediatrics, University of Rochester Medical Center, Rochester, New York
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25
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Hilgendorff A, Reiss I, Ehrhardt H, Eickelberg O, Alvira CM. Chronic lung disease in the preterm infant. Lessons learned from animal models. Am J Respir Cell Mol Biol 2014; 50:233-45. [PMID: 24024524 DOI: 10.1165/rcmb.2013-0014tr] [Citation(s) in RCA: 89] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Neonatal chronic lung disease, also known as bronchopulmonary dysplasia (BPD), is the most common complication of premature birth, affecting up to 30% of very low birth weight infants. Improved medical care has allowed for the survival of the most premature infants and has significantly changed the pathology of BPD from a disease marked by severe lung injury to the "new" form characterized by alveolar hypoplasia and impaired vascular development. However, increased patient survival has led to a paucity of pathologic specimens available from infants with BPD. This, combined with the lack of a system to model alveolarization in vitro, has resulted in a great need for animal models that mimic key features of the disease. To this end, a number of animal models have been created by exposing the immature lung to injuries induced by hyperoxia, mechanical stretch, and inflammation and most recently by the genetic modification of mice. These animal studies have 1) allowed insight into the mechanisms that determine alveolar growth, 2) delineated factors central to the pathogenesis of neonatal chronic lung disease, and 3) informed the development of new therapies. In this review, we summarize the key findings and limitations of the most common animal models of BPD and discuss how knowledge obtained from these studies has informed clinical care. Future studies should aim to provide a more complete understanding of the pathways that preserve and repair alveolar growth during injury, which might be translated into novel strategies to treat lung diseases in infants and adults.
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Affiliation(s)
- Anne Hilgendorff
- 1 Department of Perinatology Grosshadern, Ludwig-Maximilian-University, Munich, Germany
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26
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Yee M, Buczynski BW, O’Reilly MA. Neonatal hyperoxia stimulates the expansion of alveolar epithelial type II cells. Am J Respir Cell Mol Biol 2014; 50:757-66. [PMID: 24188066 PMCID: PMC4068921 DOI: 10.1165/rcmb.2013-0207oc] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2013] [Accepted: 10/29/2013] [Indexed: 01/02/2023] Open
Abstract
Supplemental oxygen used to treat infants born prematurely disrupts angiogenesis and is a risk factor for persistent pulmonary disease later in life. Although it is unclear how neonatal oxygen affects development of the respiratory epithelium, alveolar simplification and depletion of type II cells has been observed in adult mice exposed to hyperoxia between postnatal Days 0 and 4. Because hyperoxia inhibits cell proliferation, we hypothesized that it depleted the adult lung of type II cells by inhibiting their proliferation at birth. Newborn mice were exposed to room air (RA) or hyperoxia, and the oxygen-exposed mice were recovered in RA. Hyperoxia stimulated mRNA expressed by type II (Sftpc, Abca3) and type I (T1α, Aquaporin 5) cells and inhibited Pecam expressed by endothelial cells. 5-Bromo-2'-deoxyuridine labeling and fate mapping with enhanced green fluorescence protein controlled statically by the Sftpc promoter or conditionally by the Scgb1a1 promoter revealed increased Sftpc and Abca3 mRNA seen on Day 4 reflected an increase in expansion of type II cells shortly after birth. When mice were returned to RA, this expanded population of type II cells was slowly depleted until few were detected by 8 weeks. These findings reveal that hyperoxia stimulates alveolar epithelial cell expansion when it disrupts angiogenesis. The loss of type II cells during recovery in RA may contribute to persistent pulmonary diseases such as those reported in children born preterm who were exposed to supplemental oxygen.
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Affiliation(s)
- Min Yee
- Department of Pediatrics and
| | - Bradley W. Buczynski
- Department of Environmental Medicine, School of Medicine and Dentistry, The University of Rochester, Rochester New York
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27
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Ahlfeld SK, Conway SJ. Assessment of inhibited alveolar-capillary membrane structural development and function in bronchopulmonary dysplasia. ACTA ACUST UNITED AC 2014; 100:168-79. [PMID: 24604816 DOI: 10.1002/bdra.23226] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2013] [Revised: 01/17/2014] [Accepted: 01/19/2014] [Indexed: 12/20/2022]
Abstract
Bronchopulmonary dysplasia (BPD) is a chronic lung disease of extreme prematurity and is defined clinically by dependence on supplemental oxygen due to impaired gas exchange. Optimal gas exchange is dependent on the development of a sufficient surface area for diffusion. In the mammalian lung, rapid acquisition of distal lung surface area is accomplished in neonatal and early adult life by means of vascularization and secondary septation of distal lung airspaces. Extreme preterm birth interrupts secondary septation and pulmonary capillary development and ultimately reduces the efficiency of the alveolar-capillary membrane. Although pulmonary health in BPD infants rapidly improves over the first few years, persistent alveolar-capillary membrane dysfunction continues into adolescence and adulthood. Preventative therapies have been largely ineffective, and therapies aimed at promoting normal development of the air-blood barrier in infants with established BPD remain largely unexplored. The purpose of this review will be: (1) to summarize the histological evidence of aberrant alveolar-capillary membrane development associated with extreme preterm birth and BPD, (2) to review the clinical evidence assessing the long-term impact of BPD on alveolar-capillary membrane function, and (3) to discuss the need to develop and incorporate direct measurements of functional gas exchange into clinically relevant animal models of inhibited alveolar development.
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Affiliation(s)
- Shawn K Ahlfeld
- Developmental Biology and Neonatal Medicine Program, HB Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana
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28
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Regal JF, Lawrence BP, Johnson AC, Lojovich SJ, O’Reilly MA. Neonatal oxygen exposure alters airway hyper-responsiveness but not the response to allergen challenge in adult mice. Pediatr Allergy Immunol 2014; 25:180-6. [PMID: 24520985 PMCID: PMC3976144 DOI: 10.1111/pai.12206] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 01/18/2014] [Indexed: 11/29/2022]
Abstract
BACKGROUND Infants born prematurely are often treated with supplemental oxygen, which can increase their risk for airway hyper-responsiveness (AHR), asthma, reduced lung function, and altered responses to respiratory viral infections later in childhood. Likewise, exposure of newborn mice to hyperoxia alters baseline pulmonary mechanics and the host response to influenza A virus infection in adult mice. Here, we use this mouse model to test the hypothesis that neonatal hyperoxia also promotes AHR and exacerbated allergen-induced symptoms in adult mice. METHODS Baseline lung mechanics and AHR measured by methacholine provocation were assessed in adult male and female mice exposed to room air or 100% oxygen (hyperoxia) between post-natal days 0-4. AHR and lung inflammation were evaluated after adult female mice were sensitized with ovalbumin (OVA) plus alum and challenged with aerosolized OVA. RESULTS Baseline lung compliance increased and resistance decreased in adult female, but not male, mice exposed to neonatal hyperoxia compared with siblings exposed to room air. Neonatal hyperoxia significantly enhanced methacholine-induced AHR in female mice, but did not affect allergen-induced AHR to methacholine or lung inflammation. CONCLUSION Increased incidence of AHR and asthma is reported in children born prematurely and exposed to supplemental oxygen. Our findings in adult female mice exposed to hyperoxia as neonates suggest that this AHR reported in children born prematurely may reflect non-atopic wheezing due to intrinsic structural changes in airway development.
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Affiliation(s)
- Jean F. Regal
- Department of Biomedical Sciences University of Minnesota Medical School, Duluth, Minnesota, USA
| | - B. Paige Lawrence
- Department of Environmental Medicine, University of Rochester, Rochester, New York, USA
| | - Alex C. Johnson
- Department of Biomedical Sciences University of Minnesota Medical School, Duluth, Minnesota, USA
| | - Sarah J. Lojovich
- Department of Biomedical Sciences University of Minnesota Medical School, Duluth, Minnesota, USA
| | - Michael A. O’Reilly
- Department of Pediatrics School of Medicine and Dentistry, University of Rochester, Rochester, New York, USA
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29
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Bhandari V. Postnatal inflammation in the pathogenesis of bronchopulmonary dysplasia. ACTA ACUST UNITED AC 2014; 100:189-201. [PMID: 24578018 DOI: 10.1002/bdra.23220] [Citation(s) in RCA: 75] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2013] [Revised: 01/02/2014] [Accepted: 01/05/2014] [Indexed: 12/18/2022]
Abstract
Exposure to hyperoxia, invasive mechanical ventilation, and systemic/local sepsis are important antecedents of postnatal inflammation in the pathogenesis of bronchopulmonary dysplasia (BPD). This review will summarize information obtained from animal (baboon, lamb/sheep, rat and mouse) models that pertain to the specific inflammatory agents and signaling molecules that predispose a premature infant to BPD.
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Affiliation(s)
- Vineet Bhandari
- Division of Perinatal Medicine, Department of Pediatrics, Yale University School of Medicine, New Haven, Connecticut
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30
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Madurga A, Mižíková I, Ruiz-Camp J, Vadász I, Herold S, Mayer K, Fehrenbach H, Seeger W, Morty RE. Systemic hydrogen sulfide administration partially restores normal alveolarization in an experimental animal model of bronchopulmonary dysplasia. Am J Physiol Lung Cell Mol Physiol 2014; 306:L684-97. [PMID: 24508731 DOI: 10.1152/ajplung.00361.2013] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Arrested alveolarization is the pathological hallmark of bronchopulmonary dysplasia (BPD), a complication of premature birth. Here, the impact of systemic application of hydrogen sulfide (H2S) on postnatal alveolarization was assessed in a mouse BPD model. Exposure of newborn mice to 85% O2 for 10 days reduced the total lung alveoli number by 56% and increased alveolar septal wall thickness by 29%, as assessed by state-of-the-art stereological analysis. Systemic application of H2S via the slow-release H2S donor GYY4137 for 10 days resulted in pronounced improvement in lung alveolarization in pups breathing 85% O2, compared with vehicle-treated littermates. Although without impact on lung oxidative status, systemic H2S blunted leukocyte infiltration into alveolar air spaces provoked by hyperoxia, and restored normal lung interleukin 10 levels that were otherwise depressed by 85% O2. Treatment of primary mouse alveolar type II (ATII) cells with the rapid-release H2S donor NaHS had no impact on cell viability; however, NaHS promoted ATII cell migration. Although exposure of ATII cells to 85% O2 caused dramatic changes in mRNA expression, exposure to either GYY4137 or NaHS had no impact on ATII cell mRNA expression, as assessed by microarray, suggesting that the effects observed were independent of changes in gene expression. The impact of NaHS on ATII cell migration was attenuated by glibenclamide, implicating ion channels, and was accompanied by activation of Akt, hinting at two possible mechanisms of H2S action. These data support further investigation of H2S as a candidate interventional strategy to limit the arrested alveolarization associated with BPD.
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Affiliation(s)
- Alicia Madurga
- Dept. of Lung Development and Remodelling, Max Planck Institute for Heart and Lung Research, Parkstrasse 1, D-61231 Bad Nauheim, Germany.
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31
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Witsch TJ, Turowski P, Sakkas E, Niess G, Becker S, Herold S, Mayer K, Vadász I, Roberts JD, Seeger W, Morty RE. Deregulation of the lysyl hydroxylase matrix cross-linking system in experimental and clinical bronchopulmonary dysplasia. Am J Physiol Lung Cell Mol Physiol 2013; 306:L246-59. [PMID: 24285264 DOI: 10.1152/ajplung.00109.2013] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Bronchopulmonary dysplasia (BPD) is a common and serious complication of premature birth, characterized by a pronounced arrest of alveolar development. The underlying pathophysiological mechanisms are poorly understood although perturbations to the maturation and remodeling of the extracellular matrix (ECM) are emerging as candidate disease pathomechanisms. In this study, the expression and regulation of three members of the lysyl hydroxylase family of ECM remodeling enzymes (Plod1, Plod2, and Plod3) in clinical BPD, as well as in an experimental animal model of BPD, were addressed. All three enzymes were localized to the septal walls in developing mouse lungs, with Plod1 also expressed in the vessel walls of the developing lung and Plod3 expressed uniquely at the base of developing septa. The expression of plod1, plod2, and plod3 was upregulated in the lungs of mouse pups exposed to 85% O2, an experimental animal model of BPD. Transforming growth factor (TGF)-β increased plod2 mRNA levels and activated the plod2 promoter in vitro in lung epithelial cells and in lung fibroblasts. Using in vivo neutralization of TGF-β signaling in the experimental animal model of BPD, TGF-β was identified as the regulator of aberrant plod2 expression. PLOD2 mRNA expression was also elevated in human neonates who died with BPD or at risk for BPD, compared with neonates matched for gestational age at birth or chronological age at death. These data point to potential roles for lysyl hydroxylases in normal lung development, as well as in perturbed late lung development associated with BPD.
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Affiliation(s)
- Thilo J Witsch
- Dept. of Lung Development and Remodelling, Max Planck Institute for Heart and Lung Research, Parkstrasse 1, D-61231 Bad Nauheim, Germany.
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Madurga A, Mizíková I, Ruiz-Camp J, Morty RE. Recent advances in late lung development and the pathogenesis of bronchopulmonary dysplasia. Am J Physiol Lung Cell Mol Physiol 2013; 305:L893-905. [PMID: 24213917 DOI: 10.1152/ajplung.00267.2013] [Citation(s) in RCA: 113] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
In contrast to early lung development, a process exemplified by the branching of the developing airways, the later development of the immature lung remains very poorly understood. A key event in late lung development is secondary septation, in which secondary septa arise from primary septa, creating a greater number of alveoli of a smaller size, which dramatically expands the surface area over which gas exchange can take place. Secondary septation, together with architectural changes to the vascular structure of the lung that minimize the distance between the inspired air and the blood, are the objectives of late lung development. The process of late lung development is disturbed in bronchopulmonary dysplasia (BPD), a disease of prematurely born infants in which the structural development of the alveoli is blunted as a consequence of inflammation, volutrauma, and oxygen toxicity. This review aims to highlight notable recent developments in our understanding of late lung development and the pathogenesis of BPD.
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Affiliation(s)
- Alicia Madurga
- Dept. of Lung Development and Remodelling, Max Planck Institute for Heart and Lung Research, Parkstrasse 1, D-61231 Bad Nauheim, Germany.
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Buczynski BW, Yee M, Martin KC, Lawrence BP, O'Reilly MA. Neonatal hyperoxia alters the host response to influenza A virus infection in adult mice through multiple pathways. Am J Physiol Lung Cell Mol Physiol 2013; 305:L282-90. [PMID: 23748535 DOI: 10.1152/ajplung.00112.2013] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Exposing preterm infants or newborn mice to high concentrations of oxygen disrupts lung development and alters the response to respiratory viral infections later in life. Superoxide dismutase (SOD) has been separately shown to mitigate hyperoxia-mediated changes in lung development and attenuate virus-mediated lung inflammation. However, its potential to protect adult mice exposed to hyperoxia as neonates against viral infection is not known. Here, transgenic mice overexpressing extracellular (EC)-SOD in alveolar type II epithelial cells are used to test whether SOD can alleviate the deviant pulmonary response to influenza virus infection in adult mice exposed to hyperoxia as neonates. Fibrotic lung disease, observed following infection in wild-type (WT) mice exposed to hyperoxia as neonates, was prevented by overexpression of EC-SOD. However, leukocyte recruitment remained excessive, and levels of monocyte chemoattractant protein (MCP)-1 remained modestly elevated following infection in EC-SOD Tg mice exposed to hyperoxia as neonates. Because MCP-1 is often associated with pulmonary inflammation and fibrosis, the host response to infection was concurrently evaluated in adult Mcp-1 WT and Mcp-1 knockout mice exposed to neonatal hyperoxia. In contrast to EC-SOD, excessive leukocyte recruitment, but not lung fibrosis, was dependent upon MCP-1. Our findings demonstrate that neonatal hyperoxia alters the inflammatory and fibrotic responses to influenza A virus infection through different pathways. Therefore, these data suggest that multiple therapeutic strategies may be needed to provide complete protection against diseases attributed to prematurity and early life exposure to oxygen.
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Affiliation(s)
- Bradley W Buczynski
- Dept. of Pediatrics, Box 850, The Univ. of Rochester, School of Medicine and Dentistry, 601 Elmwood Ave., Rochester, NY 14642.
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Abstract
Supplemental oxygen is often used as a life-saving therapy in the treatment of preterm infants. However, its protracted use can lead to the development of bronchopulmonary dysplasia (BPD), and more recently, has been associated with adversely affecting the general health of children and adolescents who were born preterm. Efforts to understand how exposure to excess oxygen can disrupt lung development have historically focused on the interplay between oxidative stress and antioxidant defense mechanisms. However, there has been a growing appreciation for how changes in gene-environment interactions occurring during critically important periods of organ development can profoundly affect human health and disease later in life. Here, we review the concept that oxygen is an environmental stressor that may play an important role at birth to control normal lung development via its interactions with genes and cells. Understanding how changes in the oxygen environment have the potential to alter the developmental programing of the lung, such that it now proceeds along a different developmental trajectory, could lead to novel therapies in the prevention and treatment of respiratory diseases, such as BPD.
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Affiliation(s)
- Bradley W. Buczynski
- Department of Environmental Medicine, School of Medicine and Dentistry, The University of Rochester, Rochester NY 14642,Address Correspondence to: Bradley W. Buczynski, M.S., Department of Environmental Medicine, Box EHSC, The University of Rochester, School of Medicine and Dentistry, 601 Elmwood Avenue, Rochester, NY 14642, Tel: (585) 273-4831, . Michael A. O’Reilly, Ph.D., Department of Pediatrics, Box 850, The University of Rochester, School of Medicine and Dentistry, 601 Elmwood Avenue, Rochester, NY 14642, Tel: (585) 275-5948, Fax: (585) 756-7780,
| | - Echezona T. Maduekwe
- Department of Pediatrics, School of Medicine and Dentistry, The University of Rochester, Rochester NY 14642
| | - Michael A. O’Reilly
- Department of Pediatrics, School of Medicine and Dentistry, The University of Rochester, Rochester NY 14642,Address Correspondence to: Bradley W. Buczynski, M.S., Department of Environmental Medicine, Box EHSC, The University of Rochester, School of Medicine and Dentistry, 601 Elmwood Avenue, Rochester, NY 14642, Tel: (585) 273-4831, . Michael A. O’Reilly, Ph.D., Department of Pediatrics, Box 850, The University of Rochester, School of Medicine and Dentistry, 601 Elmwood Avenue, Rochester, NY 14642, Tel: (585) 275-5948, Fax: (585) 756-7780,
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Yee M, Buczynski BW, Lawrence BP, O'Reilly MA. Neonatal hyperoxia increases sensitivity of adult mice to bleomycin-induced lung fibrosis. Am J Respir Cell Mol Biol 2012; 48:258-66. [PMID: 23258231 DOI: 10.1165/rcmb.2012-0238oc] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Supplemental oxygen used to treat infants born prematurely constitutes a major risk factor for long-term deficits in lung function and host defense against respiratory infections. Likewise, neonatal oxygen exposure results in alveolar simplification in adult mice, and enhances leukocyte recruitment and fibrosis when adult mice are infected with a sublethal dose of influenza A virus. Because pulmonary fibrosis was not observed in infected adult mice exposed to room air as neonates, previous neonatal oxygen exposure may have reprogrammed how the adult lung responds to epithelial injury. By administering bleomycin to adult mice exposed to room air or hyperoxia as neonates, we tested the hypothesis that neonatal hyperoxia enhances fibrosis when the epithelium is injured by direct fibrotic stimulus. Increased sensitivity to bleomycin-induced lung fibrosis was observed in adult mice exposed to neonatal hyperoxia, and was associated with increased numbers of leukocytes and an accumulation of active transforming growth factor (TGF)-β1 in the lung. Fate mapping of the respiratory epithelium revealed that the epithelial-mesenchymal transition was not a significant source of fibroblasts in room air-exposed or oxygen-exposed mice treated with bleomycin. Instead, the treatment of mice with anti-Gr-1 antibody that depletes neutrophils and myeloid-derived suppressor cells reduced the early activation of TGF-β1 and attenuated hyperoxia-enhanced fibrosis. Because bleomycin and influenza A virus both cause epithelial injury, understanding how neonatal hyperoxia reprograms the epithelial response to these two different injurious agents could lead to new therapeutic opportunities for treating lung diseases attributed to prematurity.
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Affiliation(s)
- Min Yee
- Department of Pediatrics, School of Medicine and Dentistry, University of Rochester, Rochester, NY 14642, USA
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