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Chaudhry FN, Michki NS, Shirmer DL, McGrath-Morrow S, Young LR, Frank DB, Zepp JA. Dynamic Hippo pathway activity underlies mesenchymal differentiation during lung alveolar morphogenesis. Development 2024; 151:dev202430. [PMID: 38602485 DOI: 10.1242/dev.202430] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Accepted: 03/26/2024] [Indexed: 04/12/2024]
Abstract
Alveologenesis, the final stage in lung development, substantially remodels the distal lung, expanding the alveolar surface area for efficient gas exchange. Secondary crest myofibroblasts (SCMF) exist transiently in the neonatal distal lung and are crucial for alveologenesis. However, the pathways that regulate SCMF function, proliferation and temporal identity remain poorly understood. To address this, we purified SCMFs from reporter mice, performed bulk RNA-seq and found dynamic changes in Hippo-signaling components during alveologenesis. We deleted the Hippo effectors Yap/Taz from Acta2-expressing cells at the onset of alveologenesis, causing a significant arrest in alveolar development. Using single cell RNA-seq, we identified a distinct cluster of cells in mutant lungs with altered expression of marker genes associated with proximal mesenchymal cell types, airway smooth muscle and alveolar duct myofibroblasts. In vitro studies confirmed that Yap/Taz regulates myofibroblast-associated gene signature and contractility. Together, our findings show that Yap/Taz is essential for maintaining functional myofibroblast identity during postnatal alveologenesis.
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Affiliation(s)
- Fatima N Chaudhry
- Division of Pulmonary and Sleep Medicine, Department of Pediatrics, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Nigel S Michki
- Division of Pulmonary and Sleep Medicine, Department of Pediatrics, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
- Division of Cardiology, Department of Pediatrics, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Dain L Shirmer
- Division of Pulmonary and Sleep Medicine, Department of Pediatrics, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Sharon McGrath-Morrow
- Division of Pulmonary and Sleep Medicine, Department of Pediatrics, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Lisa R Young
- Division of Pulmonary and Sleep Medicine, Department of Pediatrics, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - David B Frank
- Division of Cardiology, Department of Pediatrics, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Jarod A Zepp
- Division of Pulmonary and Sleep Medicine, Department of Pediatrics, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
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2
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Yin Y, Koenitzer JR, Patra D, Dietmann S, Bayguinov P, Hagan AS, Ornitz DM. Identification of a myofibroblast differentiation program during neonatal lung development. Development 2024:dev.202659. [PMID: 38602479 DOI: 10.1242/dev.202659] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2023] [Accepted: 03/25/2024] [Indexed: 04/12/2024]
Abstract
Alveologenesis is the final stage of lung development in which the internal surface area of the lung is increased to facilitate efficient gas exchange in the mature organism. The first phase of alveologenesis involves the formation of septal ridges (secondary septae) and the second phase involves thinning of the alveolar septa. Within secondary septa, mesenchymal cells include a transient population of alveolar myofibroblasts (MyoFB) and a stable but poorly described population of lipid rich cells that have been referred to as lipofibroblasts or matrix fibroblasts (MatFB). Using a unique Fgf18CreER lineage trace mouse line, cell sorting, single cell RNA sequencing, and primary cell culture, we have identified multiple subtypes of mesenchymal cells in the neonatal lung, including an immature progenitor cell that gives rise to mature MyoFB. We also show that the endogenous and targeted ROSA26 locus serves as a sensitive reporter for MyoFB maturation. These studies identify a MyoFB differentiation program that is distinct from other mesenchymal cell types and increases the known repertoire of mesenchymal cell types in the neonatal lung.
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Affiliation(s)
- Yongjun Yin
- Departments of Developmental Biology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Jeffrey R Koenitzer
- Departments of Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Debabrata Patra
- Departments of Developmental Biology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Sabine Dietmann
- Departments of Developmental Biology, Washington University School of Medicine, St. Louis, MO 63110, USA
- Institute for Informatics, Data Science & Biostatistics, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Peter Bayguinov
- Departments of Neuroscience, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Andrew S Hagan
- Departments of Developmental Biology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - David M Ornitz
- Departments of Developmental Biology, Washington University School of Medicine, St. Louis, MO 63110, USA
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3
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Yin Y, Koenitzer JR, Patra D, Dietmann S, Bayguinov P, Hagan AS, Ornitz DM. Identification of a myofibroblast differentiation program during neonatal lung development. bioRxiv 2023:2023.12.28.573370. [PMID: 38234814 PMCID: PMC10793446 DOI: 10.1101/2023.12.28.573370] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2024]
Abstract
Alveologenesis is the final stage of lung development in which the internal surface area of the lung is increased to facilitate efficient gas exchange in the mature organism. The first phase of alveologenesis involves the formation of septal ridges (secondary septae) and the second phase involves thinning of the alveolar septa. Within secondary septa, mesenchymal cells include a transient population of alveolar myofibroblasts (MyoFB) and a stable but poorly described population of lipid rich cells that have been referred to as lipofibroblasts or matrix fibroblasts (MatFB). Using a unique Fgf18CreER lineage trace mouse line, cell sorting, single cell RNA sequencing, and primary cell culture, we have identified multiple subtypes of mesenchymal cells in the neonatal lung, including an immature progenitor cell that gives rise to mature MyoFB. We also show that the endogenous and targeted ROSA26 locus serves as a sensitive reporter for MyoFB maturation. These studies identify a myofibroblast differentiation program that is distinct form other mesenchymal cells types and increases the known repertoire of mesenchymal cell types in the neonatal lung.
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Affiliation(s)
- Yongjun Yin
- Departments of Developmental Biology, Washington University School of Medicine, St. Louis, MO 63110
| | | | - Debabrata Patra
- Departments of Developmental Biology, Washington University School of Medicine, St. Louis, MO 63110
| | - Sabine Dietmann
- Departments of Developmental Biology, Washington University School of Medicine, St. Louis, MO 63110
- Institute for Informatics, Data Science & Biostatistics, Washington University School of Medicine, St. Louis, MO 63110
| | - Peter Bayguinov
- Neuroscience, Washington University School of Medicine, St. Louis, MO 63110
| | - Andrew S. Hagan
- Departments of Developmental Biology, Washington University School of Medicine, St. Louis, MO 63110
| | - David M. Ornitz
- Departments of Developmental Biology, Washington University School of Medicine, St. Louis, MO 63110
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4
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Goodwin AT, John AE, Joseph C, Habgood A, Tatler AL, Susztak K, Palmer M, Offermanns S, Henderson NC, Jenkins RG. Stretch regulates alveologenesis and homeostasis via mesenchymal Gαq/11-mediated TGFβ2 activation. Development 2023; 150:dev201046. [PMID: 37102682 PMCID: PMC10259661 DOI: 10.1242/dev.201046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Accepted: 04/05/2023] [Indexed: 04/28/2023]
Abstract
Alveolar development and repair require tight spatiotemporal regulation of numerous signalling pathways that are influenced by chemical and mechanical stimuli. Mesenchymal cells play key roles in numerous developmental processes. Transforming growth factor-β (TGFβ) is essential for alveologenesis and lung repair, and the G protein α subunits Gαq and Gα11 (Gαq/11) transmit mechanical and chemical signals to activate TGFβ in epithelial cells. To understand the role of mesenchymal Gαq/11 in lung development, we generated constitutive (Pdgfrb-Cre+/-;Gnaqfl/fl;Gna11-/-) and inducible (Pdgfrb-Cre/ERT2+/-;Gnaqfl/fl;Gna11-/-) mesenchymal Gαq/11 deleted mice. Mice with constitutive Gαq/11 gene deletion exhibited abnormal alveolar development, with suppressed myofibroblast differentiation, altered mesenchymal cell synthetic function, and reduced lung TGFβ2 deposition, as well as kidney abnormalities. Tamoxifen-induced mesenchymal Gαq/11 gene deletion in adult mice resulted in emphysema associated with reduced TGFβ2 and elastin deposition. Cyclical mechanical stretch-induced TGFβ activation required Gαq/11 signalling and serine protease activity, but was independent of integrins, suggesting an isoform-specific role for TGFβ2 in this model. These data highlight a previously undescribed mechanism of cyclical stretch-induced Gαq/11-dependent TGFβ2 signalling in mesenchymal cells, which is imperative for normal alveologenesis and maintenance of lung homeostasis.
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Affiliation(s)
- Amanda T. Goodwin
- Centre for Respiratory Research, Translational Medical Sciences, School of Medicine, University of Nottingham, Nottingham, NG7 2RD, UK
- Respiratory Medicine, Nottingham NIHR Biomedical Research Centre, Nottingham, NG7 2RD, UK
- Respiratory Medicine, Biodiscovery Institute, University Park, University of Nottingham, Nottingham, NG7 2RD, UK
| | - Alison E. John
- Margaret Turner Warwick Centre for Fibrosing Lung Disease, National Heart and Lung Institute, Imperial College London, London, SW3 6LY, UK
| | - Chitra Joseph
- Centre for Respiratory Research, Translational Medical Sciences, School of Medicine, University of Nottingham, Nottingham, NG7 2RD, UK
- Respiratory Medicine, Nottingham NIHR Biomedical Research Centre, Nottingham, NG7 2RD, UK
- Respiratory Medicine, Biodiscovery Institute, University Park, University of Nottingham, Nottingham, NG7 2RD, UK
| | - Anthony Habgood
- Centre for Respiratory Research, Translational Medical Sciences, School of Medicine, University of Nottingham, Nottingham, NG7 2RD, UK
- Respiratory Medicine, Nottingham NIHR Biomedical Research Centre, Nottingham, NG7 2RD, UK
- Respiratory Medicine, Biodiscovery Institute, University Park, University of Nottingham, Nottingham, NG7 2RD, UK
| | - Amanda L. Tatler
- Centre for Respiratory Research, Translational Medical Sciences, School of Medicine, University of Nottingham, Nottingham, NG7 2RD, UK
- Respiratory Medicine, Nottingham NIHR Biomedical Research Centre, Nottingham, NG7 2RD, UK
- Respiratory Medicine, Biodiscovery Institute, University Park, University of Nottingham, Nottingham, NG7 2RD, UK
| | - Katalin Susztak
- Department of Medicine, Division of Nephrology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
| | - Matthew Palmer
- Department of Pathology, Division of Nephrology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104-4238, USA
| | - Stefan Offermanns
- Department of Pharmacology, Max Planck Institute for Heart and Lung Research, 61231 Bad Nauheim, Germany
| | - Neil C. Henderson
- Centre for Inflammation Research, University of Edinburgh, EH16 4TJ, UK
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, EH4 2XU, UK
| | - R. Gisli Jenkins
- Margaret Turner Warwick Centre for Fibrosing Lung Disease, National Heart and Lung Institute, Imperial College London, London, SW3 6LY, UK
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5
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Al-Khaldi S, Almohanna F, Barnawi R, Fallatah M, Islam SS, Ghebeh H, Al-Alwan M. Fascin is essential for mammary gland lactogenesis. Dev Biol 2022; 492:25-36. [PMID: 36152869 DOI: 10.1016/j.ydbio.2022.09.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Revised: 05/29/2022] [Accepted: 09/16/2022] [Indexed: 11/03/2022]
Abstract
Fascin expression has commonly been observed in certain subtypes of breast cancer, where its expression is associated with poor clinical outcome. However, its role in normal mammary gland development has not been elucidated. Here, we used a fascin knockout mouse model to assess its role in normal mammary gland morphogenesis and lactation. Fascin knockout was not embryonically lethal, and its effect on the litter size or condition at birth was minimal. However, litter survival until the weaning stage significantly depended on fascin expression solely in the nursing dams. Accordingly, pups that nursed from fascin-/- dams had smaller milk spots in their abdomen, suggesting a lactation defect in the nursing dams. Mammary gland whole-mounts of pregnant and lactating fascin-/- mice showed significantly reduced side branching and alveologenesis. Despite a typical composition of basal, luminal, and stromal subsets of mammary cells and normal ductal architecture of myoepithelial and luminal layers, the percentage of alveolar progenitors (ALDH+) in fascin-/- epithelial fraction was significantly reduced. Further in-depth analyses of fascin-/- mammary glands showed a significant reduction in the expression of Elf5, the master regulator of alveologenesis, and a decrease in the activity of its downstream target p-STAT5. In agreement, there was a significant reduction in the expression of the milk proteins, whey acidic protein (WAP), and β-casein in fascin-/- mammary glands. Collectively, our data demonstrate, for the first time, the physiological role of fascin in normal mammary gland lactogenesis, an addition that could reveal its contribution to breast cancer initiation and progression.
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Affiliation(s)
- Samiyah Al-Khaldi
- National Center for Biotechnology, Life Science and Environment Research Institute, King Abdulaziz City for Sciences and Technology, Riyadh, Saudi Arabia.
| | | | | | - Mohannad Fallatah
- National Center for Biotechnology, Life Science and Environment Research Institute, King Abdulaziz City for Sciences and Technology, Riyadh, Saudi Arabia.
| | - Syed S Islam
- Molecular Oncology, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia; Collage of Medicine, Al-Faisal University, Riyadh, Saudi Arabia.
| | - Hazem Ghebeh
- Stem Cell and Tissue Re-Engineering Program, Saudi Arabia; Collage of Medicine, Al-Faisal University, Riyadh, Saudi Arabia.
| | - Monther Al-Alwan
- Stem Cell and Tissue Re-Engineering Program, Saudi Arabia; Collage of Medicine, Al-Faisal University, Riyadh, Saudi Arabia.
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6
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Gao F, Li C, Danopoulos S, Al Alam D, Peinado N, Webster S, Borok Z, Kohbodi GA, Bellusci S, Minoo P. Hedgehog-responsive PDGFRa(+) fibroblasts maintain a unique pool of alveolar epithelial progenitor cells during alveologenesis. Cell Rep 2022; 39:110608. [PMID: 35385750 PMCID: PMC9199394 DOI: 10.1016/j.celrep.2022.110608] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Revised: 12/06/2021] [Accepted: 03/11/2022] [Indexed: 01/08/2023] Open
Abstract
The lung alveolus is lined with alveolar type 1 (AT1) and type 2 (AT2) epithelial cells. During alveologenesis, increasing demand associated with expanding alveolar numbers is met by proliferating progenitor AT2s (pAT2). Little information exists regarding the identity of this population and their niche microenvironment. We show that during alveologenesis, Hedgehog-responsive PDGFRa(+) progenitors (also known as SCMFs) are a source of secreted trophic molecules that maintain a unique pAT2 population. SCMFs are in turn maintained by TGFβ signaling. Compound inactivation of Alk5 TβR2 in SCMFs reduced their numbers and depleted the pAT2 pool without impacting differentiation of daughter cells. In lungs of preterm infants who died with bronchopulmonary dysplasia, PDGFRa is reduced and the number of proliferative AT2s is diminished, indicating that an evolutionarily conserved mechanism governs pAT2 behavior during alveologenesis. SCMFs are a transient cell population, active only during alveologenesis, making them a unique stage-specific niche mesodermal cell type in mammalian organs.
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Affiliation(s)
- Feng Gao
- Division of Neonatology, Department of Pediatrics, LAC+USC Medical Center and Childrens Hospital Los Angeles, Los Angeles, CA 90033, USA
| | - Changgong Li
- Division of Neonatology, Department of Pediatrics, LAC+USC Medical Center and Childrens Hospital Los Angeles, Los Angeles, CA 90033, USA
| | - Soula Danopoulos
- Lundquist Institute for Biomedical Innovation at Harbor-UCLA Medical Center, Torrance, CA 90502, USA
| | - Denise Al Alam
- Lundquist Institute for Biomedical Innovation at Harbor-UCLA Medical Center, Torrance, CA 90502, USA
| | - Neil Peinado
- Division of Neonatology, Department of Pediatrics, LAC+USC Medical Center and Childrens Hospital Los Angeles, Los Angeles, CA 90033, USA
| | - Sha Webster
- Division of Neonatology, Department of Pediatrics, LAC+USC Medical Center and Childrens Hospital Los Angeles, Los Angeles, CA 90033, USA
| | - Zea Borok
- Hastings Center for Pulmonary Research, Keck School of Medicine of University of Southern California, Los Angeles, CA 90033, USA; Division of Pulmonary, Critical Care and Sleep Medicine, University of California San Diego School of Medicine, San Diego, CA 92093, USA
| | - GoleNaz Adeli Kohbodi
- Division of Neonatology, Department of Pediatrics, LAC+USC Medical Center and Childrens Hospital Los Angeles, Los Angeles, CA 90033, USA
| | - Saverio Bellusci
- Division of Neonatology, Department of Pediatrics, LAC+USC Medical Center and Childrens Hospital Los Angeles, Los Angeles, CA 90033, USA; Universities of Giessen and Marburg Lung Center (UGMLC), Justus-Liebig-University Giessen, German Center for Lung Research (DZL), 35390 Giessen, Germany
| | - Parviz Minoo
- Division of Neonatology, Department of Pediatrics, LAC+USC Medical Center and Childrens Hospital Los Angeles, Los Angeles, CA 90033, USA; Hastings Center for Pulmonary Research, Keck School of Medicine of University of Southern California, Los Angeles, CA 90033, USA.
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7
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Fang Y, Shao H, Wu Q, Wong NC, Tsong N, Sime PJ, Que J. Epithelial Wntless regulates postnatal alveologenesis. Development 2022; 149:273807. [PMID: 34931663 PMCID: PMC8881739 DOI: 10.1242/dev.199505] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Accepted: 12/09/2021] [Indexed: 01/12/2023]
Abstract
Alveologenesis requires the coordinated modulation of the epithelial and mesenchymal compartments to generate mature alveolar saccules for efficient gas exchange. However, the molecular mechanisms underlying the epithelial-mesenchymal interaction during alveologenesis are poorly understood. Here, we report that Wnts produced by epithelial cells are crucial for neonatal alveologenesis. Deletion of the Wnt chaperone protein Wntless homolog (Wls) disrupts alveolar formation, resulting in enlarged saccules in Sftpc-Cre/Nkx2.1-Cre; Wlsloxp/loxp mutants. Although commitment of the alveolar epithelium is unaffected, α-SMA+ mesenchymal cells persist in the alveoli, accompanied by increased collagen deposition, and mutants exhibit exacerbated fibrosis following bleomycin challenge. Notably, α-SMA+ cells include a significant number of endothelial cells resembling endothelial to mesenchymal transition (EndMT), which is also present in Ager-CreER; Wlsloxp/loxp mutants following early postnatal Wls deletion. These findings provide initial evidence that epithelial-derived Wnts are crucial for the differentiation of the surrounding mesenchyme during early postnatal alveologenesis.
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Affiliation(s)
- Yinshan Fang
- Division of Digestive and Liver Diseases, Department of Medicine, Columbia Center for Human Development, Columbia University Medical Center, New York, NY 10032, USA
| | - Hongxia Shao
- Division of Digestive and Liver Diseases, Department of Medicine, Columbia Center for Human Development, Columbia University Medical Center, New York, NY 10032, USA,Tianjin Haihe Hospital, Tianjin, Tianjin 300350, China
| | - Qi Wu
- Tianjin Haihe Hospital, Tianjin, Tianjin 300350, China
| | - Neng Chun Wong
- Division of Digestive and Liver Diseases, Department of Medicine, Columbia Center for Human Development, Columbia University Medical Center, New York, NY 10032, USA
| | - Natalie Tsong
- Division of Digestive and Liver Diseases, Department of Medicine, Columbia Center for Human Development, Columbia University Medical Center, New York, NY 10032, USA
| | - Patricia J. Sime
- Department of Internal Medicine, Virginia Commonwealth University in Richmond, Richmond, VA 23298, USA
| | - Jianwen Que
- Division of Digestive and Liver Diseases, Department of Medicine, Columbia Center for Human Development, Columbia University Medical Center, New York, NY 10032, USA,Author for correspondence ()
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Walker MR, Amante JJ, Li J, Liu H, Zhu LJ, Feltri ML, Goel HL, Mercurio AM. Alveolar progenitor cells in the mammary gland are dependent on the β4 integrin. Dev Biol 2020; 457:13-9. [PMID: 31586558 DOI: 10.1016/j.ydbio.2019.10.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Revised: 09/18/2019] [Accepted: 10/01/2019] [Indexed: 01/13/2023]
Abstract
Understanding how progenitor cell function is regulated in the mammary gland is an important developmental problem that has significant implications for breast cancer. Although it had been assumed that the expression the α6β4 integrin (β4) is restricted to the basal lineage, we report that alveolar progenitor cells in the mouse mammary gland also express this integrin based on analysis of single cell RNA-Seq data. Subsequent experiments using a mouse mammary epithelial cell line (NMuMG) confirmed this finding and revealed that β4 is essential for maintaining progenitor function as assessed by serial passage mammosphere assays. These data were substantiated by analyzing the alveolar progenitor population isolated from nulliparous mouse mammary glands. Based on the finding that the alveolar progenitor cells express Whey Acidic Protein (WAP), WAP-Cre mice were crossed with itgβ4flox/flox mice to generate conditional knock-out of β4 in alveolar progenitor cells. These itgβ4flox/floxWAP-Cre+ mice exhibited significant defects in alveologenesis and milk production during pregnancy compared to itgβ4flox/floxWAP-Cre- mice, establishing a novel role for the β4 integrin in alveolar progenitor function and alveologenesis.
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9
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Ma G, Gao A, Yang Y, He Y, Zhang X, Zhang B, Zhang Z, Li M, Fu X, Zhao D, Wu R, Qi L, Hu Q, Li J, Fu L, Zhu Z, Dong JT. Zfhx3 is essential for progesterone/progesterone receptor signaling to drive ductal side-branching and alveologenesis in mouse mammary glands. J Genet Genomics 2019; 46:119-131. [PMID: 30954439 DOI: 10.1016/j.jgg.2019.03.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Accepted: 03/05/2019] [Indexed: 01/26/2023]
Abstract
Progesterone (Pg)/progesterone receptor (PR) signaling drives mammary gland side-branching and alveologenesis, but the mechanisms through which Pg/PR signaling functions remain to be clarified. Using in vitro and in vivo models and histological and molecular analyses, we determined the role of Zfhx3 transcription factor in mammary gland development driven by Pg/PR signaling. Postnatal deletion of Zfhx3 in mouse mammary epithelial cells attenuated side-branching morphogenesis and alveologenesis. These effects were undetectable in the absence of Pg/PR signaling. During the estrus cycle, Zfhx3 expression corresponded to that of Pg, being at the highest level at the diestrus stage; Zfhx3 deletion inhibited mammary gland branching more potently at diestrus than estrus stage. Loss of Zfhx3 not only attenuated the expansion of stem/progenitor cells driven by Pg/PR signaling, but also impaired the function of Pg/PR signaling in the transcriptional activation of multiple genes. In addition, Pg/PR signaling significantly expanded PR- and Zfhx3-positive epithelial cells, and induced the physical association of ZFHX3 with PR. These findings establish Zfhx3 as an integral transcription factor of Pg/PR signaling in driving side-branching and alveologenesis during mammary gland development.
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Affiliation(s)
- Gui Ma
- Department of Genetics and Cell Biology, College of Life Sciences, Nankai University, Tianjin, 300071, China
| | - Ang Gao
- Department of Genetics and Cell Biology, College of Life Sciences, Nankai University, Tianjin, 300071, China
| | - Yinan Yang
- Department of Genetics and Cell Biology, College of Life Sciences, Nankai University, Tianjin, 300071, China
| | - Yuan He
- Department of Genetics and Cell Biology, College of Life Sciences, Nankai University, Tianjin, 300071, China
| | - Xi Zhang
- Department of Genetics and Cell Biology, College of Life Sciences, Nankai University, Tianjin, 300071, China
| | - Baotong Zhang
- Department of Hematology and Medical Oncology, School of Medicine, Winship Cancer Institute, Emory University, Atlanta, GA, 30322, USA
| | - Zhiqian Zhang
- Department of Genetics and Cell Biology, College of Life Sciences, Nankai University, Tianjin, 300071, China
| | - Mei Li
- Ningbo Institute of Medical Sciences, Ningbo, 315020, China
| | - Xing Fu
- Department of Genetics and Cell Biology, College of Life Sciences, Nankai University, Tianjin, 300071, China
| | - Dan Zhao
- Department of Genetics and Cell Biology, College of Life Sciences, Nankai University, Tianjin, 300071, China
| | - Rui Wu
- Department of Genetics and Cell Biology, College of Life Sciences, Nankai University, Tianjin, 300071, China
| | - Leilei Qi
- Department of Genetics and Cell Biology, College of Life Sciences, Nankai University, Tianjin, 300071, China
| | - Qingxia Hu
- Department of Genetics and Cell Biology, College of Life Sciences, Nankai University, Tianjin, 300071, China
| | - Juan Li
- Department of Genetics and Cell Biology, College of Life Sciences, Nankai University, Tianjin, 300071, China
| | - Liya Fu
- Department of Genetics and Cell Biology, College of Life Sciences, Nankai University, Tianjin, 300071, China
| | - Zhengmao Zhu
- Department of Genetics and Cell Biology, College of Life Sciences, Nankai University, Tianjin, 300071, China
| | - Jin-Tang Dong
- Department of Genetics and Cell Biology, College of Life Sciences, Nankai University, Tianjin, 300071, China; Department of Hematology and Medical Oncology, School of Medicine, Winship Cancer Institute, Emory University, Atlanta, GA, 30322, USA.
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10
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Abstract
Although it is necessary and part of standard practice, supplemental oxygen (40-90% O2) or hyperoxia is a significant contributing factor to development of bronchopulmonary dysplasia, persistent pulmonary hypertension, recurrent wheezing, and asthma in preterm infants. This chapter discusses hyperoxia and the role of redox signaling in the context of neonatal lung growth and disease. Here, we discuss how hyperoxia promotes dysfunction in the airway and the known redox-mediated mechanisms that are important for postnatal vascular and alveolar development. Whether in the airway or alveoli, redox pathways are important and greatly influence the neonatal lung.
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Affiliation(s)
- Christina M Pabelick
- Department of Anesthesiology, College of Medicine, Mayo Clinic, 4-184 W Jos SMH, 200 First St SW, Rochester, MN, 55905, USA. .,Departments Physiology and Biomedical Engineering, College of Medicine, Mayo Clinic, 4-184 W Jos SMH, 200 First St SW, Rochester, MN, 55905, USA.
| | - Michael A Thompson
- Department of Anesthesiology, College of Medicine, Mayo Clinic, 4-184 W Jos SMH, 200 First St SW, Rochester, MN, 55905, USA
| | - Rodney D Britt
- Departments Physiology and Biomedical Engineering, College of Medicine, Mayo Clinic, 4-184 W Jos SMH, 200 First St SW, Rochester, MN, 55905, USA
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11
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Li R, Herriges JC, Chen L, Mecham RP, Sun X. FGF receptors control alveolar elastogenesis. Development 2017; 144:4563-4572. [PMID: 29122839 DOI: 10.1242/dev.149443] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2017] [Accepted: 09/28/2017] [Indexed: 12/21/2022]
Abstract
Alveologenesis, the final step of lung development, is characterized by the formation of millions of alveolar septa that constitute the vast gas-exchange surface area. The genetic network driving alveologenesis is poorly understood compared with earlier steps in lung development. FGF signaling through receptors Fgfr3 and Fgfr4 is crucial for alveologenesis, but the mechanisms through which they mediate this process remain unclear. Here we show that in Fgfr3;Fgfr4 (Fgfr3;4) global mutant mice, alveolar simplification is first observed at the onset of alveologenesis at postnatal day 3. This is preceded by disorganization of elastin, indicating defects in the extracellular matrix (ECM). Although Fgfr3 and Fgfr4 are expressed in the mesenchyme and epithelium, inactivation in the mesenchyme, but not the epithelium, recapitulated the defects. Expression analysis of components of the elastogenesis machinery revealed that Mfap5 (also known as Magp2), which encodes an elastin-microfibril bridging factor, is upregulated in Fgfr3;4 mutants. Mfap5 mutation in the Fgfr3;4 mutant background partially attenuated the alveologenesis defects. These data demonstrate that, during normal lung maturation, FGF signaling restricts expression of the elastogenic machinery in the lung mesenchyme to control orderly formation of the elastin ECM, thereby driving alveolar septa formation to increase the gas-exchange surface.
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Affiliation(s)
- Rongbo Li
- Department of Pediatrics, University of California, San Diego, La Jolla, CA 92093, USA.,Laboratory of Genetics, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - John C Herriges
- Laboratory of Genetics, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Lin Chen
- Department of Rehabilitation Medicine, Center of Bone Metabolism and Repair (CBMR), Trauma Center, State Key Laboratory of Trauma, Burns and Combined Injury, Daping Hospital, Third Military Medical University, Chongqing 400042, China
| | - Robert P Mecham
- Department of Cell Biology & Physiology, Washington University School of Medicine, Saint Louis, MO 631103, USA
| | - Xin Sun
- Department of Pediatrics, University of California, San Diego, La Jolla, CA 92093, USA .,Laboratory of Genetics, University of Wisconsin-Madison, Madison, WI 53706, USA
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12
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Shahzad T, Radajewski S, Chao CM, Bellusci S, Ehrhardt H. Pathogenesis of bronchopulmonary dysplasia: when inflammation meets organ development. Mol Cell Pediatr 2016; 3:23. [PMID: 27357257 PMCID: PMC4927524 DOI: 10.1186/s40348-016-0051-9] [Citation(s) in RCA: 76] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Accepted: 06/20/2016] [Indexed: 01/12/2023] Open
Abstract
Bronchopulmonary dysplasia is a chronic lung disease of preterm infants. It is caused by the disturbance of physiologic lung development mainly in the saccular stage with lifelong restrictions of pulmonary function and an increased risk of abnormal somatic and psychomotor development. The contributors to this disease’s entity are multifactorial with pre- and postnatal origin. Central to the pathogenesis of bronchopulmonary is the induction of a massive pulmonary inflammatory response due to mechanical ventilation and oxygen toxicity. The extent of the pro-inflammatory reaction and the disturbance of further alveolar growth and vasculogenesis vary largely and can be modified by prenatal infections, antenatal steroids, and surfactant application. This minireview summarizes the important recent research findings on the pulmonary inflammatory reaction obtained in patient cohorts and in experimental models. Unfortunately, recent changes in clinical practice based on these findings had only limited impact on the incidence of bronchopulmonary dysplasia.
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Affiliation(s)
- Tayyab Shahzad
- 1Department of General Pediatrics and Neonatology, Center for Pediatrics and Youth Medicine, Justus-Liebig-University, Feulgenstrasse 12, D-35392 Gießen, Universities of Gießen and Marburg Lung Center (UGMLC), Member of the German Lung Research Center (DZL), Giessen, Germany.,University of Giessen Lung Center, Excellence Cluster Cardio-Pulmonary Systems, Member of the German Lung Center, Department of Internal Medicine II, Aulweg 130, 35392, Giessen, Germany
| | - Sarah Radajewski
- 1Department of General Pediatrics and Neonatology, Center for Pediatrics and Youth Medicine, Justus-Liebig-University, Feulgenstrasse 12, D-35392 Gießen, Universities of Gießen and Marburg Lung Center (UGMLC), Member of the German Lung Research Center (DZL), Giessen, Germany.,University of Giessen Lung Center, Excellence Cluster Cardio-Pulmonary Systems, Member of the German Lung Center, Department of Internal Medicine II, Aulweg 130, 35392, Giessen, Germany
| | - Cho-Ming Chao
- 1Department of General Pediatrics and Neonatology, Center for Pediatrics and Youth Medicine, Justus-Liebig-University, Feulgenstrasse 12, D-35392 Gießen, Universities of Gießen and Marburg Lung Center (UGMLC), Member of the German Lung Research Center (DZL), Giessen, Germany.,University of Giessen Lung Center, Excellence Cluster Cardio-Pulmonary Systems, Member of the German Lung Center, Department of Internal Medicine II, Aulweg 130, 35392, Giessen, Germany
| | - Saverio Bellusci
- University of Giessen Lung Center, Excellence Cluster Cardio-Pulmonary Systems, Member of the German Lung Center, Department of Internal Medicine II, Aulweg 130, 35392, Giessen, Germany
| | - Harald Ehrhardt
- 1Department of General Pediatrics and Neonatology, Center for Pediatrics and Youth Medicine, Justus-Liebig-University, Feulgenstrasse 12, D-35392 Gießen, Universities of Gießen and Marburg Lung Center (UGMLC), Member of the German Lung Research Center (DZL), Giessen, Germany. .,University of Giessen Lung Center, Excellence Cluster Cardio-Pulmonary Systems, Member of the German Lung Center, Department of Internal Medicine II, Aulweg 130, 35392, Giessen, Germany.
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13
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Chao CM, Moiseenko A, Zimmer KP, Bellusci S. Alveologenesis: key cellular players and fibroblast growth factor 10 signaling. Mol Cell Pediatr 2016; 3:17. [PMID: 27098664 PMCID: PMC4840179 DOI: 10.1186/s40348-016-0045-7] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2015] [Accepted: 04/14/2016] [Indexed: 11/26/2022] Open
Abstract
Background Alveologenesis is the last stage in lung development and is essential for building the gas-exchanging units called alveoli. Despite intensive lung research, the intricate crosstalk between mesenchymal and epithelial cell lineages during alveologenesis is poorly understood. This crosstalk contributes to the formation of the secondary septae, which are key structures of healthy alveoli. Conclusions A better understanding of the cellular and molecular processes underlying the formation of the secondary septae is critical for the development of new therapies to protect or regenerate the alveoli. This review summarizes briefly the alveologenesis process in mouse and human. Further, it discusses the current knowledge on the epithelial and mesenchymal progenitor cells during early lung development giving rise to the key cellular players (e.g., alveolar epithelial cell type I, alveolar epithelial cell type II, alveolar myofibroblast, lipofibroblast) involved in alveologenesis. This review focusses mainly on the role of fibroblast growth factor 10 (FGF10), one of the most important signaling molecules during lung development, in epithelial and mesenchymal cell lineage formation.
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Affiliation(s)
- Cho-Ming Chao
- Universities of Giessen and Marburg Lung Center (UGMLC), Excellence Cluster Cardio-Pulmonary System (ECCPS), Member of the German Center for Lung Research (DZL), Department of Internal Medicine II, Aulweg 130, 35392, Giessen, Germany.,Division of General Pediatrics and Neonatology, University Children's Hospital Gießen, Justus-Liebig-University, Gießen, Germany
| | - Alena Moiseenko
- Universities of Giessen and Marburg Lung Center (UGMLC), Excellence Cluster Cardio-Pulmonary System (ECCPS), Member of the German Center for Lung Research (DZL), Department of Internal Medicine II, Aulweg 130, 35392, Giessen, Germany
| | - Klaus-Peter Zimmer
- Division of General Pediatrics and Neonatology, University Children's Hospital Gießen, Justus-Liebig-University, Gießen, Germany
| | - Saverio Bellusci
- Universities of Giessen and Marburg Lung Center (UGMLC), Excellence Cluster Cardio-Pulmonary System (ECCPS), Member of the German Center for Lung Research (DZL), Department of Internal Medicine II, Aulweg 130, 35392, Giessen, Germany. .,Institute of Fundamental Medicine and Biology, Kazan (Volga Region) Federal University, Kazan, Russian Federation.
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14
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Chen C, Breslin MB, Lan MS. Ectopic expression of a small cell lung cancer transcription factor, INSM1 impairs alveologenesis in lung development. BMC Pulm Med 2016; 16:49. [PMID: 27072116 PMCID: PMC4830008 DOI: 10.1186/s12890-016-0215-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Accepted: 04/04/2016] [Indexed: 02/08/2023] Open
Abstract
Background Insulinoma associated-1 (INSM1) gene is expressed exclusively in early embryonic neuroendocrine tissues, but has been found highly re-activated in most of the neuroendocrine tumors including small cell lung carcinoma. Methods In order to elucidate the functional effects of INSM1 in normal lung development, we used a conditional lung-specific INSM1 transgenic mouse model. Transgenic (Tet-on system) CMV-INSM1 responder mice were bred with the lung-specific, club cell secretory protein (CCSP) promoter-rtTA activator mice to produce bi-transgenic progeny carrying both alleles, CCSP-rtTA and Tet-on-INSM1. Mice were fed with doxycycline containing food at the initial mating day to the postnatal day 21. Lung samples were collected at embryonic day 17.5, newborn, and postnatal day 21 for analyses. Results Northern blot, RT-PCR, and immunohistochemical analyses revealed that doxycycline induced respiratory epithelium-specific INSM1 expression in bi-transgenic mice. Samples from postnatal day 21 mice revealed a larger lung size in the bi-transgenic mouse as compared to the single-transgenic or wild-type littermates. The histopathology results showed that the alveolar space in the bi-transgenic mice were 4 times larger than those in the single transgenic or wild-type littermates. In contrast, the size was not significantly different in the lungs collected at E17.5 or newborn among the bi-transgenic, single transgenic, or wild type mice. The respiratory epithelium with INSM1 ectopic expression suppressed cyclin D1 signal. Further in vitro studies revealed that the ectopic expression of INSM1 suppresses cyclin D1 expression and delays cell cycle progression. Conclusion The current study suggests that CCSP promoter-driven INSM1 ectopic expression impairs normal lung development especially in postnatal alveologenesis.
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Affiliation(s)
- Chiachen Chen
- Research Institute for Children, Children's Hospital, 200 Henry Clay Avenue, Research and Education Building, Room. 2211, New Orleans, LA, 70118, USA.,Departments of Pediatrics, Louisiana State University Health Sciences Center, New Orleans, LA, 70112, USA
| | - Mary B Breslin
- Research Institute for Children, Children's Hospital, 200 Henry Clay Avenue, Research and Education Building, Room. 2211, New Orleans, LA, 70118, USA.,Departments of Pediatrics, Louisiana State University Health Sciences Center, New Orleans, LA, 70112, USA
| | - Michael S Lan
- Research Institute for Children, Children's Hospital, 200 Henry Clay Avenue, Research and Education Building, Room. 2211, New Orleans, LA, 70118, USA. .,Departments of Pediatrics, Louisiana State University Health Sciences Center, New Orleans, LA, 70112, USA. .,Departments of Genetics, Louisiana State University Health Sciences Center, New Orleans, LA, 70112, USA.
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15
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Branchfield K, Li R, Lungova V, Verheyden JM, McCulley D, Sun X. A three-dimensional study of alveologenesis in mouse lung. Dev Biol 2015; 409:429-41. [PMID: 26632490 DOI: 10.1016/j.ydbio.2015.11.017] [Citation(s) in RCA: 99] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Revised: 11/23/2015] [Accepted: 11/23/2015] [Indexed: 01/08/2023]
Abstract
Alveologenesis is the final step of lung maturation, which subdivides the alveolar region of the lung into smaller units called alveoli. Each of the nascent dividers serves as a new gas-exchange surface, and collectively they drastically increase the surface area for breathing. Disruption of alveologenesis results in simplification of alveoli, as is seen in premature infants diagnosed with bronchopulmonary dysplasia (BPD), a prevalent lung disease that is often associated with lifelong breathing deficiencies. To date, a majority of studies of alveologenesis rely on two-dimensional (2D) analysis of tissue sections. Given that an overarching theme of alveologenesis is thinning and extension of the epithelium and mesenchyme to facilitate gas exchange, often only a small portion of a cell or a cellular structure is represented in a single 2D plane. Here, we use a three-dimensional (3D) approach to examine the structural architecture and cellular composition of myofibroblasts, alveolar type 2 cells, elastin and lipid droplets in normal as well as BPD-like mouse lung. We found that 2D finger-like septal crests, commonly used to depict growing alveolar septae, are often artifacts of sectioning through fully established alveolar walls. Instead, a more accurate representation of growing septae are 3D ridges that are lined by platelet-derived growth factor receptor alpha (PDGFRA) and alpha smooth muscle actin (α-SMA)-expressing myofibroblasts, as well as the elastin fibers that they produce. Accordingly in 3D, both α-SMA and elastin were each found in connected networks underlying the 3D septal ridges rather than as isolated dots at the tip of 2D septal crests. Analysis through representative stages of alveologenesis revealed unappreciated dynamic changes in these patterns. PDGFRA-expressing cells are only α-SMA-positive during the first phase of alveologenesis, but not in the second phase, suggesting that the two phases of septae formation may be driven by distinct mechanisms. Thin elastin fibers are already present in the alveolar region prior to alveologenesis, suggesting that during alveologenesis, there is not only new elastin deposition, but also extensive remodeling to transform thin and uniformly distributed fibers into thick cables that rim the nascent septae. Analysis of several genetic as well as hyperoxia-induced models of BPD revealed that the myofibroblast organization is perturbed in all, regardless of whether the origin of defect is epithelial, mesenchymal, endothelial or environmental. Finally, analysis of relative position of PDGFRA-positive cells and alveolar type 2 cells reveal that during alveologenesis, these two cell types are not always adjacent to one another. This result suggests that the niche and progenitor relationship afforded by their close juxtaposition in the adult lung may be a later acquired property. These insights revealed by 3D reconstruction of the septae set the foundation for future investigations of the mechanisms driving normal alveologenesis, as well as causes of alveolar simplification in BPD.
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Affiliation(s)
- Kelsey Branchfield
- Laboratory of Genetics, University of Wisconsin-Madison Madison, WI 52706, United States
| | - Rongbo Li
- Laboratory of Genetics, University of Wisconsin-Madison Madison, WI 52706, United States
| | - Vlasta Lungova
- Department of Surgery, University of Wisconsin-Madison Madison, WI 53706, United States
| | - Jamie M Verheyden
- Laboratory of Genetics, University of Wisconsin-Madison Madison, WI 52706, United States
| | - David McCulley
- Department of Pediatrics University of Wisconsin-Madison Madison, WI 53706, United States
| | - Xin Sun
- Laboratory of Genetics, University of Wisconsin-Madison Madison, WI 52706, United States.
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16
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Gajewska M, Zielniok K, Debski B, Motyl T. IGF-I retards proper development of acinar structures formed by bovine mammary epithelial cells via sustained activation of Akt kinase. Domest Anim Endocrinol 2013; 45:111-21. [PMID: 23932581 DOI: 10.1016/j.domaniend.2013.06.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2013] [Revised: 06/24/2013] [Accepted: 06/26/2013] [Indexed: 11/29/2022]
Abstract
Insulin-like growth factor-I is involved in mammary gland development, promoting proliferation and inhibiting apoptosis of mammary epithelial cells (MECs). Mitogenic actions of IGF-I are mainly mediated by the phosphatidylinositol-3 kinase (PI3K)/Akt signaling pathway. We have found that in the presence of IGF-I bovine BME-UV1 MECs cultured on reconstituted basement membrane form large spheroids with disrupted polarity and no cavity in the center. These cells showed enhanced phosphorylation of Akt, decreased level of cleaved caspase-3, and sustained proliferative activity throughout the 16-d period of 3-dimensional culture. Inhibition of the PI3K/Akt pathway by a specific inhibitor of PI3K, LY294002, resulted in the restoration of the normal acinar phenotype. However, this effect was noted only when LY294002 was added in the second week of 3-dimensional culture, which corresponded with the time of cell cycle arrest and polarity formation under control conditions. Normal development of acini was also obtained when BME-UV1 cells were treated simultaneously with IGF-I and 17β-estradiol. The addition of 17β-estradiol regulated Akt activation, enabling the subsequent initiation of polarization processes. 17β-Estradiol also increased the level of IGFBP-3 protein in MECs cultured on Matrigel in the presence of IGF-I. The presented results indicate important interactions between signaling pathways activated by estrogen and IGF-I, which regulate alveologenesis in bovine mammary gland.
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Affiliation(s)
- M Gajewska
- Department of Physiological Sciences, Faculty of Veterinary Medicine, Warsaw University of Life Sciences, Nowoursynowska 159, 02-776 Warsaw, Poland.
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