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Luo Y, Cao K, Chiu J, Chen H, Wang HJ, Thornton ME, Grubbs BH, Kolb M, Parmacek MS, Mishina Y, Shi W. Defective mesenchymal Bmpr1a-mediated BMP signaling causes congenital pulmonary cysts. eLife 2024; 12:RP91876. [PMID: 38856718 PMCID: PMC11164533 DOI: 10.7554/elife.91876] [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] [Indexed: 06/11/2024] Open
Abstract
Abnormal lung development can cause congenital pulmonary cysts, the mechanisms of which remain largely unknown. Although the cystic lesions are believed to result directly from disrupted airway epithelial cell growth, the extent to which developmental defects in lung mesenchymal cells contribute to abnormal airway epithelial cell growth and subsequent cystic lesions has not been thoroughly examined. In the present study using genetic mouse models, we dissected the roles of bone morphogenetic protein (BMP) receptor 1a (Bmpr1a)-mediated BMP signaling in lung mesenchyme during prenatal lung development and discovered that abrogation of mesenchymal Bmpr1a disrupted normal lung branching morphogenesis, leading to the formation of prenatal pulmonary cystic lesions. Severe deficiency of airway smooth muscle cells and subepithelial elastin fibers were found in the cystic airways of the mesenchymal Bmpr1a knockout lungs. In addition, ectopic mesenchymal expression of BMP ligands and airway epithelial perturbation of the Sox2-Sox9 proximal-distal axis were detected in the mesenchymal Bmpr1a knockout lungs. However, deletion of Smad1/5, two major BMP signaling downstream effectors, from the lung mesenchyme did not phenocopy the cystic abnormalities observed in the mesenchymal Bmpr1a knockout lungs, suggesting that a Smad-independent mechanism contributes to prenatal pulmonary cystic lesions. These findings reveal for the first time the role of mesenchymal BMP signaling in lung development and a potential pathogenic mechanism underlying congenital pulmonary cysts.
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Affiliation(s)
- Yongfeng Luo
- Department of Surgery, Children’s Hospital Los Angeles, Keck School of Medicine, University of Southern CaliforniaLos AngelesUnited States
| | - Ke Cao
- Division of Pulmonary, Critical Care & Sleep Medicine, Department of Internal Medicine, University of Cincinnati College of MedicineCincinnatiUnited States
| | - Joanne Chiu
- Department of Surgery, Children’s Hospital Los Angeles, Keck School of Medicine, University of Southern CaliforniaLos AngelesUnited States
| | - Hui Chen
- Division of Pulmonary, Critical Care & Sleep Medicine, Department of Internal Medicine, University of Cincinnati College of MedicineCincinnatiUnited States
| | - Hong-Jun Wang
- Division of Pulmonary, Critical Care & Sleep Medicine, Department of Internal Medicine, University of Cincinnati College of MedicineCincinnatiUnited States
| | - Matthew E Thornton
- Division of Maternal Fetal Medicine, Department of Obstetrics and Gynecology, Keck School of Medicine, University of Southern CaliforniaLos AngelesUnited States
| | - Brendan H Grubbs
- Division of Maternal Fetal Medicine, Department of Obstetrics and Gynecology, Keck School of Medicine, University of Southern CaliforniaLos AngelesUnited States
| | - Martin Kolb
- Department of Medicine, McMaster UniversityHamiltonCanada
| | - Michael S Parmacek
- Department of Medicine, Perelman School of Medicine, University of PennsylvaniaPhiladelphiaUnited States
| | - Yuji Mishina
- Department of Biologic and Material Sciences, University of Michigan-Ann ArborAnn ArborUnited States
| | - Wei Shi
- Division of Pulmonary, Critical Care & Sleep Medicine, Department of Internal Medicine, University of Cincinnati College of MedicineCincinnatiUnited States
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2
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Luo Y, Cao K, Chiu J, Chen H, Wang HJ, Thornton ME, Grubbs BH, Kolb M, Parmacek MS, Mishina Y, Shi W. Defective mesenchymal Bmpr1a-mediated BMP signaling causes congenital pulmonary cysts. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.09.26.559527. [PMID: 37808788 PMCID: PMC10557633 DOI: 10.1101/2023.09.26.559527] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/10/2023]
Abstract
Abnormal lung development can cause congenital pulmonary cysts, the mechanisms of which remain largely unknown. Although the cystic lesions are believed to result directly from disrupted airway epithelial cell growth, the extent to which developmental defects in lung mesenchymal cells contribute to abnormal airway epithelial cell growth and subsequent cystic lesions has not been thoroughly examined. In the present study, we dissected the roles of BMP receptor 1a (Bmpr1a)-mediated BMP signaling in lung mesenchyme during prenatal lung development and discovered that abrogation of mesenchymal Bmpr1a disrupted normal lung branching morphogenesis, leading to the formation of prenatal pulmonary cystic lesions. Severe deficiency of airway smooth muscle cells and subepithelial elastin fibers were found in the cystic airways of the mesenchymal Bmpr1a knockout lungs. In addition, ectopic mesenchymal expression of BMP ligands and airway epithelial perturbation of the Sox2-Sox9 proximal-distal axis were detected in the mesenchymal Bmpr1a knockout lungs. However, deletion of Smad1/5, two major BMP signaling downstream effectors, from the lung mesenchyme did not phenocopy the cystic abnormalities observed in the mesenchymal Bmpr1a knockout lungs, suggesting that a Smad-independent mechanism contributes to prenatal pulmonary cystic lesions. These findings reveal for the first time the role of mesenchymal BMP signaling in lung development and a potential pathogenic mechanism underlying congenital pulmonary cysts.
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Affiliation(s)
- Yongfeng Luo
- Department of Surgery, Children’s Hospital Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, CA 90027
| | - Ke Cao
- Division of Pulmonary, Critical Care & Sleep Medicine, Department of Internal Medicine, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA
| | - Joanne Chiu
- Department of Surgery, Children’s Hospital Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, CA 90027
| | - Hui Chen
- Division of Pulmonary, Critical Care & Sleep Medicine, Department of Internal Medicine, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA
| | - Hong-Jun Wang
- Division of Pulmonary, Critical Care & Sleep Medicine, Department of Internal Medicine, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA
| | - Matthew E. Thornton
- Division of Maternal Fetal Medicine, Department of Obstetrics and Gynecology, Keck School of Medicine, University of Southern California, Los Angeles, CA 90089, USA
| | - Brendan H. Grubbs
- Division of Maternal Fetal Medicine, Department of Obstetrics and Gynecology, Keck School of Medicine, University of Southern California, Los Angeles, CA 90089, USA
| | - Martin Kolb
- Department of Medicine, McMaster University, Hamilton, ON, Canada L8N 4A6
| | - Michael S. Parmacek
- Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Yuji Mishina
- Department of Biologic and Material Sciences, University of Michigan, 1011 N. University Ave., Ann Arbor, MI 48109
| | - Wei Shi
- Division of Pulmonary, Critical Care & Sleep Medicine, Department of Internal Medicine, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA
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Yang Q, Miao Q, Chen H, Li D, Luo Y, Chiu J, Wang HJ, Chuvanjyan M, Parmacek MS, Shi W. Myocd regulates airway smooth muscle cell remodeling in response to chronic asthmatic injury. J Pathol 2023; 259:331-341. [PMID: 36484734 PMCID: PMC10107741 DOI: 10.1002/path.6044] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2022] [Revised: 11/13/2022] [Accepted: 12/06/2022] [Indexed: 12/14/2022]
Abstract
Abnormal growth of airway smooth muscle cells is one of the key features in asthmatic airway remodeling, which is associated with asthma severity. The mechanisms underlying inappropriate airway smooth muscle cell growth in asthma remain largely unknown. Myocd has been reported to act as a key transcriptional coactivator in promoting airway-specific smooth muscle development in fetal lungs. Whether Myocd controls airway smooth muscle remodeling in asthma has not been investigated. Mice with lung mesenchyme-specific deletion of Myocd after lung development were generated, and a chronic asthma model was established by sensitizing and challenging the mice with ovalbumin for a prolonged period. Comparison of the asthmatic pathology between the Myocd knockout mice and the wild-type controls revealed that abrogation of Myocd mitigated airway smooth muscle cell hypertrophy and hyperplasia, accompanied by reduced peri-airway inflammation, decreased fibrillar collagen deposition on airway walls, and attenuation of abnormal mucin production in airway epithelial cells. Our study indicates that Myocd is a key transcriptional coactivator involved in asthma airway remodeling. Inhibition of Myocd in asthmatic airways may be an effective approach to breaking the vicious cycle of asthmatic progression, providing a novel strategy in treating severe and persistent asthma. © 2022 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.
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Affiliation(s)
- Qin Yang
- Department of Surgery, Children's Hospital Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA.,Department of Respiratory Medicine, Shenzhen Children's Hospital, Shenzhen, PR China
| | - Qing Miao
- Department of Surgery, Children's Hospital Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Hui Chen
- Department of Surgery, Children's Hospital Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA.,Division of Pulmonary, Critical Care and Sleep Medicine, Department of Internal Medicine, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Duo Li
- Department of Surgery, Children's Hospital Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Yongfeng Luo
- Department of Surgery, Children's Hospital Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Joanne Chiu
- Department of Surgery, Children's Hospital Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Hong-Jun Wang
- Department of Surgery, Children's Hospital Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA.,Division of Pulmonary, Critical Care and Sleep Medicine, Department of Internal Medicine, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Michael Chuvanjyan
- Department of Surgery, Children's Hospital Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Michael S Parmacek
- Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Wei Shi
- Department of Surgery, Children's Hospital Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA.,Division of Pulmonary, Critical Care and Sleep Medicine, Department of Internal Medicine, University of Cincinnati College of Medicine, Cincinnati, OH, USA
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4
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Goodwin K, Jaslove JM, Tao H, Zhu M, Hopyan S, Nelson CM. Patterning the embryonic pulmonary mesenchyme. iScience 2022; 25:103838. [PMID: 35252804 PMCID: PMC8889149 DOI: 10.1016/j.isci.2022.103838] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Revised: 12/13/2021] [Accepted: 01/25/2022] [Indexed: 12/31/2022] Open
Abstract
Smooth muscle guides the morphogenesis of several epithelia during organogenesis, including the mammalian airways. However, it remains unclear how airway smooth muscle differentiation is spatiotemporally patterned and whether it originates from transcriptionally distinct mesenchymal progenitors. Using single-cell RNA-sequencing of embryonic mouse lungs, we show that the pulmonary mesenchyme contains a continuum of cell identities, but no transcriptionally distinct progenitors. Transcriptional variability correlates with spatially distinct sub-epithelial and sub-mesothelial mesenchymal compartments that are regulated by Wnt signaling. Live-imaging and tension-sensors reveal compartment-specific migratory behaviors and cortical forces and show that sub-epithelial mesenchyme contributes to airway smooth muscle. Reconstructing differentiation trajectories reveals early activation of cytoskeletal and Wnt signaling genes. Consistently, Wnt activation induces the earliest stages of smooth muscle differentiation and local accumulation of mesenchymal F-actin, which influences epithelial morphology. Our single-cell approach uncovers the principles of pulmonary mesenchymal patterning and identifies a morphogenetically active mesenchymal layer that sculpts the airway epithelium. The embryonic lung mesenchyme is organized into spatially distinct compartments Migratory behaviors and cortical forces differ between compartments Diffusion analysis recapitulates airway smooth muscle differentiation The early stages of smooth muscle differentiation influence airway branching
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Affiliation(s)
- Katharine Goodwin
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08544, USA
| | - Jacob M. Jaslove
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA
- Graduate School of Biomedical Sciences, Rutgers Robert Wood Johnson Medical School, Piscataway, NJ 08854, USA
| | - Hirotaka Tao
- Program in Developmental and Stem Cell Biology, Research Institute, The Hospital for Sick Children, Toronto, ON M5G 0A4, Canada
| | - Min Zhu
- Program in Developmental and Stem Cell Biology, Research Institute, The Hospital for Sick Children, Toronto, ON M5G 0A4, Canada
- Department of Mechanical and Industrial Engineering, University of Toronto, Toronto M5S 3G8, Canada
| | - Sevan Hopyan
- Program in Developmental and Stem Cell Biology, Research Institute, The Hospital for Sick Children, Toronto, ON M5G 0A4, Canada
- Department of Molecular Genetics, University of Toronto, Toronto M5S 1A8, Canada
- Division of Orthopaedic Surgery, Hospital for Sick Children and University of Toronto, Toronto M5G 1X8, Canada
| | - Celeste M. Nelson
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA
- Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ 08544, USA
- Corresponding author
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5
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Wu Y, Zhang X, Wang J, Ji R, Zhang L, Qin J, Tian M, Jin G, Zhang X. P4HA2 promotes cell proliferation and migration in glioblastoma. Oncol Lett 2021; 22:601. [PMID: 34188703 PMCID: PMC8228437 DOI: 10.3892/ol.2021.12862] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Accepted: 04/08/2021] [Indexed: 01/05/2023] Open
Abstract
Glioblastoma (GBM) is a primary malignant tumor characterized by high infiltration and angiogenesis in the brain parenchyma. Glioma stem cells (GSCs), a heterogeneous GBM cell type with the potential for self-renewal and differentiation to tumor cells, are responsible for the high malignancy of GBM. The purpose of the present study was to investigate the roles of significantly differentially expressed genes between GSCs and GBM cells in GBM progression. The gene profiles GSE74304 and GSE124145, containing 10 GSC samples and 12 GBM samples in total, were obtained from the Gene Expression Omnibus (GEO) database. The overlapping differentially expressed genes were identified with GEO2R tools and Venn software online. Subsequently, Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analysis was performed on the 41 upregulated and 142 downregulated differentially expressed genes in GSCs compared with in GBM cells via the DAVID website. Protein-protein interaction and module analyses in Cytoscape with the STRING database revealed 21 hub genes that were downregulated in GSCs compared with in GBM cells. Survival analysis conducted via the GEPIA2 website revealed that low expression levels of the hub genes prolyl 4-hydroxylase subunit α2 (P4HA2), TGF-β induced, integrin subunit α3 and thrombospondin 1 were associated with significantly prolonged survival time in patients with GBM. Further experiments were performed focusing on P4HA2. Reverse transcription-quantitative PCR was used to detect P4HA2 gene expression. In agreement with the bioinformatics analysis, P4HA2 expression was higher in U87 cells than in GSCs. Cell Counting Kit-8, EdU incorporation, cell cycle analysis, wound healing and Transwell assays demonstrated that the cell proliferation and migration increased after P4HA2 overexpression and decreased after P4HA2-knockdown. In conclusion, the present study demonstrated that low P4HA2 expression in GSCs promoted GBM cell proliferation and migration, suggesting that P4HA2 may act as a switch in the transition from GSCs to GBM cells.
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Affiliation(s)
- Yuying Wu
- Department of Anatomy, Medical School and Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu 226001, P.R. China
| | - Xunrui Zhang
- Department of Clinical Medicine, Faculty of Medicine, Xinglin College, Nantong University, Nantong, Jiangsu 226008, P.R. China
| | - Jue Wang
- Department of Anatomy, Medical School and Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu 226001, P.R. China
| | - Ruijie Ji
- Department of Anatomy, Medical School and Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu 226001, P.R. China.,Department of Clinical Medicine, Faculty of Medicine, Xinglin College, Nantong University, Nantong, Jiangsu 226008, P.R. China
| | - Lei Zhang
- Department of Anatomy, Medical School and Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu 226001, P.R. China
| | - Jianbing Qin
- Department of Anatomy, Medical School and Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu 226001, P.R. China
| | - Meiling Tian
- Department of Anatomy, Medical School and Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu 226001, P.R. China
| | - Guohua Jin
- Department of Anatomy, Medical School and Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu 226001, P.R. China
| | - Xinhua Zhang
- Department of Anatomy, Medical School and Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu 226001, P.R. China
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6
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Miao Q, Chen H, Luo Y, Chiu J, Chu L, Thornton ME, Grubbs BH, Kolb M, Lou J, Shi W. Abrogation of mesenchyme-specific TGF-β signaling results in lung malformation with prenatal pulmonary cysts in mice. Am J Physiol Lung Cell Mol Physiol 2021; 320:L1158-L1168. [PMID: 33881909 DOI: 10.1152/ajplung.00299.2020] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The TGF-β signaling pathway plays a pivotal role in controlling organogenesis during fetal development. Although the role of TGF-β signaling in promoting lung alveolar epithelial growth has been determined, mesenchymal TGF-β signaling in regulating lung development has not been studied in vivo due to a lack of genetic tools for specifically manipulating gene expression in lung mesenchymal cells. Therefore, the integral roles of TGF-β signaling in regulating lung development and congenital lung diseases are not completely understood. Using a Tbx4 lung enhancer-driven Tet-On inducible Cre transgenic mouse system, we have developed a mouse model in which lung mesenchyme-specific deletion of TGF-β receptor 2 gene (Tgfbr2) is achieved. Reduced airway branching accompanied by defective airway smooth muscle growth and later peripheral cystic lesions occurred when lung mesenchymal Tgfbr2 was deleted from embryonic day 13.5 to 15.5, resulting in postnatal death due to respiratory insufficiency. Although cell proliferation in both lung epithelium and mesenchyme was reduced, epithelial differentiation was not significantly affected. Tgfbr2 downstream Smad-independent ERK1/2 may mediate these mesenchymal effects of TGF-β signaling through the GSK3β-β-catenin-Wnt canonical pathway in fetal mouse lung. Our study suggests that Tgfbr2-mediated TGF-β signaling in prenatal lung mesenchyme is essential for lung development and maturation, and defective TGF-β signaling in lung mesenchyme may be related to abnormal airway branching morphogenesis and congenital airway cystic lesions.
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Affiliation(s)
- Qing Miao
- Department of Surgery, Children's Hospital Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, California.,Department of Allergy, Beijing Key Laboratory for Pediatric Diseases of Otolaryngology, Head and Neck Surgery, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, People's Republic of China
| | - Hui Chen
- Department of Surgery, Children's Hospital Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, California
| | - Yongfeng Luo
- Department of Surgery, Children's Hospital Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, California
| | - Joanne Chiu
- Department of Surgery, Children's Hospital Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, California
| | - Ling Chu
- Department of Surgery, Children's Hospital Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, California
| | - Matthew E Thornton
- Division of Maternal Fetal Medicine, Department of Obstetrics and Gynecology, Keck School of Medicine, University of Southern California, Los Angeles, California
| | - Brendan H Grubbs
- Division of Maternal Fetal Medicine, Department of Obstetrics and Gynecology, Keck School of Medicine, University of Southern California, Los Angeles, California
| | - Martin Kolb
- Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Ontario, Canada
| | - Jianlin Lou
- Institute of Occupational Diseases, Hangzhou Medical College (Zhejiang Academy of Medical Science), Hangzhou, People's Republic of China
| | - Wei Shi
- Department of Surgery, Children's Hospital Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, California
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7
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Chu L, Luo Y, Chen H, Miao Q, Wang L, Moats R, Wang T, Kennedy JC, Henske EP, Shi W. Mesenchymal folliculin is required for alveolar development: implications for cystic lung disease in Birt-Hogg-Dubé syndrome. Thorax 2020; 75:486-493. [PMID: 32238524 DOI: 10.1136/thoraxjnl-2019-214112] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Revised: 02/13/2020] [Accepted: 03/18/2020] [Indexed: 12/20/2022]
Abstract
BACKGROUND Pulmonary cysts and spontaneous pneumothorax are presented in most patients with Birt-Hogg-Dubé (BHD) syndrome, which is caused by loss of function mutations in the folliculin (FLCN) gene. The pathogenic mechanisms underlying the cystic lung disease in BHD are poorly understood. METHODS Mesenchymal Flcn was specifically deleted in mice or in cultured lung mesenchymal progenitor cells using a Cre/loxP approach. Dynamic changes in lung structure, cellular and molecular phenotypes and signalling were measured by histology, immunofluorescence staining and immunoblotting. RESULTS Deletion of Flcn in mesoderm-derived mesenchymal cells results in significant reduction of postnatal alveolar growth and subsequent alveolar destruction, leading to cystic lesions. Cell proliferation and alveolar myofibroblast differentiation are inhibited in the Flcn knockout lungs, and expression of the extracellular matrix proteins Col3a1 and elastin are downregulated. Signalling pathways including mTORC1, AMP-activated protein kinase, ERK1/2 and Wnt-β-catenin are differentially affected at different developmental stages. All the above changes have statistical significance (p<0.05). CONCLUSIONS Mesenchymal Flcn is an essential regulator during alveolar development and maintenance, through multiple cellular and molecular mechanisms. The mesenchymal Flcn knockout mouse model provides the first in vivo disease model that may recapitulate the stages of cyst development in human BHD. These findings elucidate the developmental origins and mechanisms of lung disease in BHD.
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Affiliation(s)
- Ling Chu
- The Third Xiangya Hospital, Central South University, Changsha, Hunan, China.,The Saban Research Institute, Children's Hospital Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
| | - Yongfeng Luo
- The Saban Research Institute, Children's Hospital Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
| | - Hui Chen
- The Saban Research Institute, Children's Hospital Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
| | - Qing Miao
- The Saban Research Institute, Children's Hospital Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
| | - Larry Wang
- The Saban Research Institute, Children's Hospital Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
| | - Rex Moats
- The Saban Research Institute, Children's Hospital Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
| | - Tiansheng Wang
- The Third Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - John C Kennedy
- Division of Pulmonary and Critical Care Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Elizabeth P Henske
- Division of Pulmonary and Critical Care Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Wei Shi
- The Saban Research Institute, Children's Hospital Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
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8
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Mesenchyme-specific deletion of Tgf-β1 in the embryonic lung disrupts branching morphogenesis and induces lung hypoplasia. J Transl Med 2019; 99:1363-1375. [PMID: 31028279 PMCID: PMC7422700 DOI: 10.1038/s41374-019-0256-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Revised: 03/06/2019] [Accepted: 03/13/2019] [Indexed: 01/08/2023] Open
Abstract
Proper lung development depends on the precise temporal and spatial expression of several morphogenic factors, including Fgf10, Fgf9, Shh, Bmp4, and Tgf-β. Over- or under-expression of these molecules often leads to aberrant embryonic or postnatal lung development. Herein, we deleted the Tgf-β1 gene specifically within the lung embryonic mesenchymal compartment at specific gestational stages to determine the contribution of this cytokine to lung development. Mutant embryos developed severe lung hypoplasia and died at birth due to the inability to breathe. Despite the markedly reduced lung size, proliferation and differentiation of the lung epithelium was not affected by the lack of mesenchymal expression of the Tgf-β1 gene, while apoptosis was significantly increased in the mutant lung parenchyma. Lack of mesenchymal expression of the Tgf-β1 gene was also associated with reduced lung branching morphogenesis, with accompanying inhibition of the local FGF10 signaling pathway as well as abnormal development of the vascular system. To shed light on the mechanism of lung hypoplasia, we quantified the phosphorylation of 226 proteins in the mutant E12.5 lung compared with control. We identified five proteins, Hrs, Vav2, c-Kit, the regulatory subunit of Pi3k (P85), and Fgfr1, that were over- or under-phosphorylated in the mutant lung, suggesting that they could be indispensable effectors of the TGF-β signaling program during embryonic lung development. In conclusion, we have uncovered novel roles of the mesenchyme-specific Tgf-β1 ligand in embryonic mouse lung development and generated a mouse model that may prove helpful to identify some of the key pathogenic mechanisms underlying lung hypoplasia in humans.
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9
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Spatial and temporal changes in extracellular elastin and laminin distribution during lung alveolar development. Sci Rep 2018; 8:8334. [PMID: 29844468 PMCID: PMC5974327 DOI: 10.1038/s41598-018-26673-1] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Accepted: 05/17/2018] [Indexed: 12/14/2022] Open
Abstract
Lung alveolarization requires precise coordination of cell growth with extracellular matrix (ECM) synthesis and deposition. The role of extracellular matrices in alveogenesis is not fully understood, because prior knowledge is largely extrapolated from two-dimensional structural analysis. Herein, we studied temporospatial changes of two important ECM proteins, laminin and elastin that are tightly associated with alveolar capillary growth and lung elastic recoil respectively, during both mouse and human lung alveolarization. By combining protein immunofluorescence staining with two- and three-dimensional imaging, we found that the laminin network was simplified along with the thinning of septal walls during alveogenesis, and more tightly associated with alveolar endothelial cells in matured lung. In contrast, elastin fibers were initially localized to the saccular openings of nascent alveoli, forming a ring-like structure. Then, throughout alveolar growth, the number of such alveolar mouth ring-like structures increased, while the relative ring size decreased. These rings were interconnected via additional elastin fibers. The apparent patches and dots of elastin at the tips of alveolar septae found in two-dimensional images were cross sections of elastin ring fibers in the three-dimension. Thus, the previous concept that deposition of elastin at alveolar tips drives septal inward growth may potentially be conceptually challenged by our data.
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10
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Gerhardt B, Leesman L, Burra K, Snowball J, Rosenzweig R, Guzman N, Ambalavanan M, Sinner D. Notum attenuates Wnt/β-catenin signaling to promote tracheal cartilage patterning. Dev Biol 2018; 436:14-27. [PMID: 29428562 DOI: 10.1016/j.ydbio.2018.02.002] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Revised: 02/05/2018] [Accepted: 02/05/2018] [Indexed: 12/20/2022]
Abstract
Tracheobronchomalacia (TBM) is a common congenital disorder in which the cartilaginous rings of the trachea are weakened or missing. Despite the high prevalence and clinical issues associated with TBM, the etiology is largely unknown. Our previous studies demonstrated that Wntless (Wls) and its associated Wnt pathways are critical for patterning of the upper airways. Deletion of Wls in respiratory endoderm caused TBM and ectopic trachealis muscle. To understand mechanisms by which Wls mediates tracheal patterning, we performed RNA sequencing in prechondrogenic tracheal tissue of Wlsf/f;ShhCre/wt embryos. Chondrogenic Bmp4, and Sox9 were decreased, while expression of myogenic genes was increased. We identified Notum, a deacylase that inactivates Wnt ligands, as a target of Wls induced Wnt signaling. Notum's mesenchymal ventral expression in prechondrogenic trachea overlaps with expression of Axin2, a Wnt/β-catenin target and inhibitor. Notum is induced by Wnt/β-catenin in developing trachea. Deletion of Notum activated mesenchymal Wnt/β-catenin and caused tracheal mispatterning of trachealis muscle and cartilage as well as tracheal stenosis. Notum is required for tracheal morphogenesis, influencing mesenchymal condensations critical for patterning of tracheal cartilage and muscle. We propose that Notum influences mesenchymal cell differentiation by generating a barrier for Wnt ligands produced and secreted by airway epithelial cells to attenuate Wnt signaling.
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Affiliation(s)
- Bradley Gerhardt
- Division of Neonatology and Pulmonary Biology, CCHMC, University of Cincinnati, College of Medicine and University Honors Program, Cincinnati, OH 45229, United States of America
| | - Lauren Leesman
- Division of Neonatology and Pulmonary Biology, CCHMC, University of Cincinnati, College of Medicine and University Honors Program, Cincinnati, OH 45229, United States of America
| | - Kaulini Burra
- Division of Neonatology and Pulmonary Biology, CCHMC, University of Cincinnati, College of Medicine and University Honors Program, Cincinnati, OH 45229, United States of America
| | - John Snowball
- Division of Neonatology and Pulmonary Biology, CCHMC, University of Cincinnati, College of Medicine and University Honors Program, Cincinnati, OH 45229, United States of America
| | - Rachel Rosenzweig
- Division of Neonatology and Pulmonary Biology, CCHMC, University of Cincinnati, College of Medicine and University Honors Program, Cincinnati, OH 45229, United States of America
| | - Natalie Guzman
- Division of Neonatology and Pulmonary Biology, CCHMC, University of Cincinnati, College of Medicine and University Honors Program, Cincinnati, OH 45229, United States of America
| | - Manoj Ambalavanan
- Division of Neonatology and Pulmonary Biology, CCHMC, University of Cincinnati, College of Medicine and University Honors Program, Cincinnati, OH 45229, United States of America
| | - Debora Sinner
- Division of Neonatology and Pulmonary Biology, CCHMC, University of Cincinnati, College of Medicine and University Honors Program, Cincinnati, OH 45229, United States of America
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11
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Hussain M, Xu C, Lu M, Wu X, Tang L, Wu X. Wnt/β-catenin signaling links embryonic lung development and asthmatic airway remodeling. Biochim Biophys Acta Mol Basis Dis 2017; 1863:3226-3242. [PMID: 28866134 DOI: 10.1016/j.bbadis.2017.08.031] [Citation(s) in RCA: 68] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Revised: 08/10/2017] [Accepted: 08/29/2017] [Indexed: 12/23/2022]
Abstract
Embryonic lung development requires reciprocal endodermal-mesodermal interactions; mediated by various signaling proteins. Wnt/β-catenin is a signaling protein that exhibits the pivotal role in lung development, injury and repair while aberrant expression of Wnt/β-catenin signaling leads to asthmatic airway remodeling: characterized by hyperplasia and hypertrophy of airway smooth muscle cells, alveolar and vascular damage goblet cells metaplasia, and deposition of extracellular matrix; resulting in decreased lung compliance and increased airway resistance. The substantial evidence suggests that Wnt/β-catenin signaling links embryonic lung development and asthmatic airway remodeling. Here, we summarized the recent advances related to the mechanistic role of Wnt/β-catenin signaling in lung development, consequences of aberrant expression or deletion of Wnt/β-catenin signaling in expansion and progression of asthmatic airway remodeling, and linking early-impaired pulmonary development and airway remodeling later in life. Finally, we emphasized all possible recent potential therapeutic significance and future prospectives, that are adaptable for therapeutic intervention to treat asthmatic airway remodeling.
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Affiliation(s)
- Musaddique Hussain
- Department of Pharmacology, School of Medicine, Zhejiang University, Hangzhou City 310058, China; The Key Respiratory Drug Research Laboratory of China Food and Drug Administration, School of Medicine, Zhejiang University, Hangzhou City 310058, China.
| | - Chengyun Xu
- Department of Pharmacology, School of Medicine, Zhejiang University, Hangzhou City 310058, China; The Key Respiratory Drug Research Laboratory of China Food and Drug Administration, School of Medicine, Zhejiang University, Hangzhou City 310058, China
| | - Meiping Lu
- Department of Respiratory Medicine, the Affiliated Children Hospital, School of Medicine, Zhejiang University, Hangzhou City 310006, China
| | - Xiling Wu
- Department of Respiratory Medicine, the Affiliated Children Hospital, School of Medicine, Zhejiang University, Hangzhou City 310006, China.
| | - Lanfang Tang
- Department of Respiratory Medicine, the Affiliated Children Hospital, School of Medicine, Zhejiang University, Hangzhou City 310006, China
| | - Ximei Wu
- Department of Pharmacology, School of Medicine, Zhejiang University, Hangzhou City 310058, China; The Key Respiratory Drug Research Laboratory of China Food and Drug Administration, School of Medicine, Zhejiang University, Hangzhou City 310058, China.
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12
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Ren S, Luo Y, Chen H, Warburton D, Lam HC, Wang LL, Chen P, Henske EP, Shi W. Inactivation of Tsc2 in Mesoderm-Derived Cells Causes Polycystic Kidney Lesions and Impairs Lung Alveolarization. THE AMERICAN JOURNAL OF PATHOLOGY 2016; 186:3261-3272. [PMID: 27768862 DOI: 10.1016/j.ajpath.2016.08.013] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2016] [Revised: 08/09/2016] [Accepted: 08/29/2016] [Indexed: 01/15/2023]
Abstract
The tuberous sclerosis complex (TSC) proteins are critical negative regulators of the mammalian/mechanistic target of rapamycin complex 1 pathway. Germline mutations of TSC1 or TSC2 cause TSC, affecting multiple organs, including the kidney and lung, and causing substantial morbidity and mortality. The mechanisms of organ-specific disease in TSC remain incompletely understood, and the impact of TSC inactivation on mesenchymal lineage cells has not been specifically studied. We deleted Tsc2 specifically in mesoderm-derived mesenchymal cells of multiple organs in mice using the Dermo1-Cre driver. The Dermo1-Cre-driven Tsc2 conditional knockout mice had body growth retardation and died approximately 3 weeks after birth. Significant phenotypes were observed in the postnatal kidney and lung. Inactivation of Tsc2 in kidney mesenchyme caused polycystic lesions starting from the second week of age, with increased cell proliferation, tubular epithelial hyperplasia, and epithelial-mesenchymal transition. In contrast, Tsc2 deletion in lung mesenchyme led to decreased cell proliferation, reduced postnatal alveolarization, and decreased differentiation with reduced numbers of alveolar myofibroblast and type II alveolar epithelial cells. Two major findings thus result from this model: inactivation of Tsc2 in mesoderm-derived cells causes increased cell proliferation in the kidneys but reduced proliferation in the lungs, and inactivation of Tsc2 in mesoderm-derived cells causes epithelial-lined renal cysts. Therefore, Tsc2-mTOR signaling in mesenchyme is essential for the maintenance of renal structure and for lung alveolarization.
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Affiliation(s)
- Siying Ren
- Department of Respiratory Medicine, The Second Xiangya Hospital, Central-South University, Changsha, People's Republic of China; Developmental Biology and Regenerative Medicine Program, The Saban Research Institute, Children's Hospital Los Angeles, Los Angeles, California
| | - Yongfeng Luo
- Developmental Biology and Regenerative Medicine Program, The Saban Research Institute, Children's Hospital Los Angeles, Los Angeles, California
| | - Hui Chen
- Developmental Biology and Regenerative Medicine Program, The Saban Research Institute, Children's Hospital Los Angeles, Los Angeles, California
| | - David Warburton
- Developmental Biology and Regenerative Medicine Program, The Saban Research Institute, Children's Hospital Los Angeles, Los Angeles, California; Department of Surgery, Keck School of Medicine, University of Southern California, Los Angeles, California
| | - Hilaire C Lam
- Division of Pulmonary and Critical Care Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts
| | - Larry L Wang
- Developmental Biology and Regenerative Medicine Program, The Saban Research Institute, Children's Hospital Los Angeles, Los Angeles, California
| | - Ping Chen
- Department of Respiratory Medicine, The Second Xiangya Hospital, Central-South University, Changsha, People's Republic of China
| | - Elizabeth P Henske
- Division of Pulmonary and Critical Care Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts.
| | - Wei Shi
- Developmental Biology and Regenerative Medicine Program, The Saban Research Institute, Children's Hospital Los Angeles, Los Angeles, California; Department of Surgery, Keck School of Medicine, University of Southern California, Los Angeles, California.
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13
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Ota C, Baarsma HA, Wagner DE, Hilgendorff A, Königshoff M. Linking bronchopulmonary dysplasia to adult chronic lung diseases: role of WNT signaling. Mol Cell Pediatr 2016; 3:34. [PMID: 27718180 PMCID: PMC5055515 DOI: 10.1186/s40348-016-0062-6] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Accepted: 09/25/2016] [Indexed: 12/21/2022] Open
Abstract
Bronchopulmonary dysplasia (BPD) is one of the most common chronic lung diseases in infants caused by pre- and/or postnatal lung injury. BPD is characterized by arrested alveolarization and vascularization due to extracellular matrix remodeling, inflammation, and impaired growth factor signaling. WNT signaling is a critical pathway for normal lung development, and its altered signaling has been shown to be involved in the onset and progression of incurable chronic lung diseases in adulthood, such as chronic obstructive pulmonary disease (COPD) or idiopathic pulmonary fibrosis (IPF). In this review, we summarize the impact of WNT signaling on different stages of lung development and its potential contribution to developmental lung diseases, especially BPD, and chronic lung diseases in adulthood.
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Affiliation(s)
- Chiharu Ota
- Comprehensive Pneumology Center, Helmholtz Center Munich, Ludwig-Maximilians-University, University Hospital Grosshadern, German Center of Lung Research (DZL), Munich, Germany.
| | - Hoeke A Baarsma
- Comprehensive Pneumology Center, Helmholtz Center Munich, Ludwig-Maximilians-University, University Hospital Grosshadern, German Center of Lung Research (DZL), Munich, Germany
| | - Darcy E Wagner
- Comprehensive Pneumology Center, Helmholtz Center Munich, Ludwig-Maximilians-University, University Hospital Grosshadern, German Center of Lung Research (DZL), Munich, Germany
| | - Anne Hilgendorff
- Comprehensive Pneumology Center, Helmholtz Center Munich, Ludwig-Maximilians-University, University Hospital Grosshadern, German Center of Lung Research (DZL), Munich, Germany.,The Perinatal Center, Campus Grosshadern, Ludwig-Maximilians-University, Munich, Germany
| | - Melanie Königshoff
- Comprehensive Pneumology Center, Helmholtz Center Munich, Ludwig-Maximilians-University, University Hospital Grosshadern, German Center of Lung Research (DZL), Munich, Germany
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14
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Luo Y, Chen H, Ren S, Li N, Mishina Y, Shi W. BMP signaling is essential in neonatal surfactant production during respiratory adaptation. Am J Physiol Lung Cell Mol Physiol 2016; 311:L29-38. [PMID: 27190064 DOI: 10.1152/ajplung.00391.2015] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2015] [Accepted: 05/17/2016] [Indexed: 01/08/2023] Open
Abstract
Deficiency in pulmonary surfactant results in neonatal respiratory distress, and the known genetic mutations in key components of surfactant only account for a small number of cases. Therefore, determining the regulatory mechanisms of surfactant production and secretion, particularly during the transition from prenatal to neonatal stages, is essential for better understanding of the pathogenesis of human neonatal respiratory distress. We have observed significant increase of bone morphogenetic protein (BMP) signaling in neonatal mouse lungs immediately after birth. Using genetically manipulated mice, we then studied the relationship between BMP signaling and surfactant production in neonates. Blockade of endogenous BMP signaling by deleting Bmpr1a (Alk3) or Smad1 in embryonic day 18.5 in perinatal lung epithelial cells resulted in severe neonatal respiratory distress and death, accompanied by atelectasis in histopathology and significant reductions of surfactant protein B and C, as well as Abca3, whereas prenatal lung development was not significantly affected. We then identified a new BMP-Smad1 downstream target, Nfatc3, which is known as an important transcription activator for surfactant proteins and Abca3. Furthermore, activation of BMP signaling in cultured lung epithelial cells was able to promote endogenous Nfatc3 expression and also stimulate the activity of an Nfatc3 promoter that contains a Smad1-binding site. Therefore, our study suggests that the BMP-Alk3-Smad1-Nfatc3 regulatory loop plays an important role in enhancing surfactant production in neonates, possibly helping neonatal respiratory adaptation from prenatal amniotic fluid environment to neonatal air breathing.
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Affiliation(s)
- Yongfeng Luo
- Saban Research Institute, Children's Hospital Los Angeles, Los Angeles, California; Department of Surgery, Keck School of Medicine, University of Southern California, Los Angeles, California
| | - Hui Chen
- Saban Research Institute, Children's Hospital Los Angeles, Los Angeles, California; Department of Surgery, Keck School of Medicine, University of Southern California, Los Angeles, California
| | - Siying Ren
- Saban Research Institute, Children's Hospital Los Angeles, Los Angeles, California; Department of Respiratory Medicine, The Second Xiangya Hospital, Central-South University, Changsha, Hunan, People's Republic of China
| | - Nan Li
- Saban Research Institute, Children's Hospital Los Angeles, Los Angeles, California; Department of Surgery, Keck School of Medicine, University of Southern California, Los Angeles, California
| | - Yuji Mishina
- Department of Biologic and Material Sciences, University of Michigan, Ann Arbor, Michigan
| | - Wei Shi
- Saban Research Institute, Children's Hospital Los Angeles, Los Angeles, California; Department of Surgery, Keck School of Medicine, University of Southern California, Los Angeles, California;
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15
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Han L, Nasr T, Zorn AM. Mesodermal lineages in the developing respiratory system. TRENDS IN DEVELOPMENTAL BIOLOGY 2016; 9:91-110. [PMID: 34707332 PMCID: PMC8547324] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The life-sustaining air-blood interface of the respiratory system requires the exquisite integration of the epithelial lining with the mesenchymal capillary network, all supported by elastic smooth muscle and rigid cartilage keeping the expandable airways open. These intimate tissue interactions originate in the early embryo, where bidirectional paracrine signaling between the endoderm epithelium and adjacent mesoderm orchestrates lung and trachea development and controls the stereotypical branching morphogenesis. Although much attention has focused on how these interactions impact the differentiation of the respiratory epithelium, relatively less is known about the patterning and differentiation of the mesenchyme. Endothelial cells, smooth muscle cells, and chondrocytes together with other types of mesenchymal cells are essential components of a functional respiratory system, and malformation of these cells can lead to various congenital defects. In this review, we summarize the current understanding of mesenchymal development in the fetal trachea and lung, focusing on recent findings from animal models that have begun to shed light on the poorly understood respiratory mesenchyme lineages.
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16
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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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