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Roberts JD. Nitric oxide regulation of fetal and newborn lung development and function. Nitric Oxide 2024; 147:13-25. [PMID: 38588917 PMCID: PMC11148871 DOI: 10.1016/j.niox.2024.04.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2024] [Revised: 03/21/2024] [Accepted: 04/05/2024] [Indexed: 04/10/2024]
Abstract
In the developing lung, nitric oxide (NO) and cyclic guanosine monophosphate (cGMP) signaling are essential in regulating lung formation and vascular tone. Animal studies have linked many anatomical and pathophysiological features of newborn lung disease to abnormalities in the NO/cGMP signaling system. They have demonstrated that driving this system with agonists and antagonists alleviates many of them. This research has spurred the rapid clinical development, testing, and application of several NO/cGMP-targeting therapies with the hope of treating and potentially preventing significant pediatric lung diseases. However, there are instances when the therapeutic effectiveness of these agents is limited. Studies indicate that injury-induced disruption of several critical components within the signaling system may hinder the promise of some of these therapies. Recent research has identified basic mechanisms that suppress NO/cGMP signaling in the injured newborn lung. They have also pinpointed biomarkers that offer insight into the activation of these pathogenic mechanisms and their influence on the NO/cGMP signaling system's integrity in vivo. Together, these will guide the development of new therapies to protect NO/cGMP signaling and safeguard newborn lung development and function. This review summarizes the important role of the NO/cGMP signaling system in regulating pulmonary development and function and our evolving understanding of how it is disrupted by newborn lung injury.
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Affiliation(s)
- Jesse D Roberts
- Cardiovascular Research Center of the General Medical Services and the Departments of Anesthesia, Critical Care and Pain Medicine, Pediatrics, and Medicine, Massachusetts General Hospital - East, 149 13th St, Boston, MA, USA; Harvard Medical School, Harvard University, Cambridge, MA, USA.
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2
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Ge R, Huang GM. Targeting transforming growth factor beta signaling in metastatic osteosarcoma. J Bone Oncol 2023; 43:100513. [PMID: 38021074 PMCID: PMC10666000 DOI: 10.1016/j.jbo.2023.100513] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2023] [Revised: 10/28/2023] [Accepted: 11/07/2023] [Indexed: 12/01/2023] Open
Abstract
Osteosarcoma is a rare type of bone cancer, and half of the cases affect children and adolescents younger than 20 years of age. Despite intensive efforts to improve both chemotherapeutics and surgical management, the clinical outcome for metastatic osteosarcoma remains poor. Transforming growth factor β (TGF-β) is one of the most abundant growth factors in bones. The TGF-β signaling pathway has complex and contradictory roles in the pathogenesis of human cancers. TGF-β is primarily a tumor suppressor that inhibits proliferation and induces apoptosis of premalignant epithelial cells. In the later stages of cancer progression, however, TGF-β functions as a metastasis promoter by promoting tumor growth, inducing epithelial-mesenchymal transition (EMT), blocking antitumor immune responses, increasing tumor-associated fibrosis, and enhancing angiogenesis. In contrast with the dual effects of TGF-β on carcinoma (epithelial origin) progression, TGF-β seems to mainly have a pro-tumoral effect on sarcomas including osteosarcoma (mesenchymal origin). Many drugs that target TGF-β signaling have been developed: neutralizing antibodies that prevent TGF-β binding to receptor complexes; ligand trap employing recombinant Fc-fusion proteins containing the soluble ectodomain of either type II (TβRII) or the type III receptor ((TβRIII), preventing TGF-β from binding to its receptors; antisense nucleotides that reduce TGF-β expression at the transcriptional/translational level; small molecule inhibitors of serine/threonine kinases of the type I receptor (TβRI) preventing downstream signaling; and vaccines that contain cell lines transfected with TβRII antisense genes, or target furin convertase, resulting in reduced TGF-β signaling. TGF-β antagonists have been shown to have effects on osteosarcoma in vitro and in vivo. One of the small molecule TβRI inhibitors, Vactosertib, is currently undergoing a phase 1/2 clinical trial to evaluate its effect on osteosarcoma. Several phase 1/2/3 clinical trials have shown TGF-β antagonists are safe and well tolerated. For instance, Luspatercept, a TGF-β ligand trap, has been approved by the FDA for the treatment of anemia associated with myeloid dysplastic syndrome (MDS) with ring sideroblasts/mutated SF3B1 with acceptable safety. Clinical trials evaluating the long-term safety of Luspatercept are in process.
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Affiliation(s)
- Rongrong Ge
- Hillman Cancer Center at Central Pennsylvania, University of Pittsburg Medical Center, Harrisburg, PA, 17109, USA
| | - Gavin M. Huang
- Harrisburg Academy School, 10 Erford Rd, Wormleysburg, PA, 17043, USA
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3
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Davies ER, Denney L, Wandel M, Lloyd CM, Davies DE, Haitchi HM. Regulation of ectodomain shedding of ADAM33 in vitro and in vivo. J Allergy Clin Immunol 2019; 143:2281-2284.e3. [PMID: 30721763 PMCID: PMC6550363 DOI: 10.1016/j.jaci.2019.01.026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2018] [Revised: 01/10/2019] [Accepted: 01/23/2019] [Indexed: 11/07/2022]
Affiliation(s)
- Elizabeth R Davies
- Brooke Laboratories, Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton, United Kingdom.
| | - Laura Denney
- Inflammation, Repair & Development, National Heart and Lung Institute, Imperial College London, London, United Kingdom
| | - Marieke Wandel
- Brooke Laboratories, Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton, United Kingdom
| | - Clare M Lloyd
- Inflammation, Repair & Development, National Heart and Lung Institute, Imperial College London, London, United Kingdom
| | - Donna E Davies
- Brooke Laboratories, Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton, United Kingdom; National Institute for Health Research Southampton Biomedical Research Centre at University Hospital Southampton NHS Foundation Trust, Southampton, United Kingdom; Institute for Life Sciences, University of Southampton, Southampton, United Kingdom
| | - Hans Michael Haitchi
- Brooke Laboratories, Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton, United Kingdom; National Institute for Health Research Southampton Biomedical Research Centre at University Hospital Southampton NHS Foundation Trust, Southampton, United Kingdom; Institute for Life Sciences, University of Southampton, Southampton, United Kingdom
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4
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Zhang H, Du L, Zhong Y, Flanders KC, Roberts JD. Transforming growth factor-β stimulates Smad1/5 signaling in pulmonary artery smooth muscle cells and fibroblasts of the newborn mouse through ALK1. Am J Physiol Lung Cell Mol Physiol 2017. [PMID: 28642261 DOI: 10.1152/ajplung.00079.2017] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The intracellular signaling mechanisms through which TGF-β regulates pulmonary development are incompletely understood. Canonical TGF-β signaling involves Smad2/3 phosphorylation, Smad2/3·Smad4 complex formation and nuclear localization, and gene regulation. Here, we show that physiologically relevant TGF-β1 levels also stimulate Smad1/5 phosphorylation, which is typically a mediator of bone morphogenetic protein (BMP) signaling, in mouse pup pulmonary artery smooth muscle cells (mPASMC) and lung fibroblasts and other interstitial lung cell lines. This cross-talk mechanism likely has in vivo relevance because mixed Smad1/5/8·Smad2/3 complexes, which are indicative of TGF-β-stimulated Smad1/5 activation, were detected in the developing mouse lung using a proximity ligation assay. Although mixed Smad complexes have been shown not to transduce nuclear signaling, we determined that TGF-β stimulates nuclear localization of phosphorylated Smad1/5 and induces the expression of prototypical BMP-regulated genes in the mPASMC. Small-molecule kinase inhibitor studies suggested that TGF-β-regulated Smad1/5 phosphorylation in these cells is mediated by TGF-β-type I receptors, not BMP-type I receptors, but possibly the accessory activin-like kinase (ALK1) receptor. Although work by others suggested that ALK1 is expressed exclusively in endothelial cells in the vasculature, we detected ALK1 mRNA and protein expression in mPASMC in vitro and in mouse pup lungs. Moreover, using an antimurine ALK1 antibody and mPASMC, we determined that ALK1 regulates Smad1/5 phosphorylation by TGF-β. Together, these studies characterize an accessory TGF-β-stimulated BMP R-Smad signaling mechanism in interstitial cells of the developing lung. They also indicate the importance of considering alternate Smad pathways in studies directed at determining how TGF-β regulates newborn lung development.
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Affiliation(s)
- Huili Zhang
- Cardiovascular Research Center of the General Medical Services, Massachusetts General Hospital, Boston, Massachusetts
| | - Lili Du
- Cardiovascular Research Center of the General Medical Services, Massachusetts General Hospital, Boston, Massachusetts
| | - Ying Zhong
- Cardiovascular Research Center of the General Medical Services, Massachusetts General Hospital, Boston, Massachusetts
| | - Kathleen C Flanders
- Laboratory of Cancer Biology and Genetics, Center for Cancer Research, National Cancer Institute, Bethesda, Maryland; and
| | - Jesse D Roberts
- Cardiovascular Research Center of the General Medical Services, Massachusetts General Hospital, Boston, Massachusetts; .,Department of Anesthesia and the Division of Newborn Medicine in the Department of Pediatrics, Massachusetts General Hospital, Boston, Massachusetts
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Abstract
The number of blood-borne chemotherapeutic agents implicated in drug-induced lung toxicity continues to increase, although problems in detection remain. The initiation of drug-induced lung injury can have an immunologic or nonimmunologic basis. If endothelial cells are injured, interstitial pulmonary edema may result. Regardless of the source of injury, the progression of drug-induced lung toxicity is often quite similar, involving (1) parenchymal damage, (2) recruitment of inflammatory cells, and (3) progression of the inflammatory process. If the inflammatory reponse is sufficiently severe and disperse, increased collagen can be deposited in interstitial and intra-alveolar areas. The resulting attenuation of gas exchange can induce dyspnea and possibly death. Recent research suggests mediation of the fibrogenic process via cytokines such as transforming growth factor-β and tumor necrosis factor. Preliminary results demonstrating amelioration of cytokine mediated lung-induced fibrosis in animal models with appropriate antibodies suggest a possible future modality of therapy. Certain amphiphilic drugs are capable of eliciting a more specific form of lung toxicity. This class of drugs can interfere with phospholipid metabolism in pulmonary macrophages. In these cases, phospholipidosis results from phospholipid accumulation. The physiologic sequelae in human phospholipidosis is still uncertain.
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Affiliation(s)
- Mannfred A. Hollinger
- Chairman Dept. of Medical Pharmacology & Toxicology School of Medicine University of California Davis, CA 95616
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6
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Ahlfeld SK, Wang J, Gao Y, Snider P, Conway SJ. Initial Suppression of Transforming Growth Factor-β Signaling and Loss of TGFBI Causes Early Alveolar Structural Defects Resulting in Bronchopulmonary Dysplasia. THE AMERICAN JOURNAL OF PATHOLOGY 2016; 186:777-93. [PMID: 26878215 DOI: 10.1016/j.ajpath.2015.11.024] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2015] [Revised: 11/02/2015] [Accepted: 11/18/2015] [Indexed: 12/22/2022]
Abstract
Septation of the gas-exchange saccules of the morphologically immature mouse lung requires regulated timing, spatial direction, and dosage of transforming growth factor (TGF)-β signaling. We found that neonatal hyperoxia acutely initially diminished saccular TGF-β signaling coincident with alveolar simplification. However, sustained hyperoxia resulted in a biphasic response and subsequent up-regulation of TGF-β signaling, ultimately resulting in bronchopulmonary dysplasia. Significantly, we found that the TGF-β-induced matricellular protein (TGFBI) was similarly biphasically altered in response to hyperoxia. Moreover, genetic ablation revealed that TGFBI was required for normal alveolar structure and function. Although the phenotype was not neonatal lethal, Tgfbi-deficient lungs were morphologically abnormal. Mutant septal tips were stunted, lacked elastin-positive tips, exhibited reduced proliferation, and contained abnormally persistent alveolar α-smooth muscle actin myofibroblasts. In addition, Tgfbi-deficient lungs misexpressed TGF-β-responsive follistatin and serpine 1, and transiently suppressed myofibroblast platelet-derived growth factor α differentiation marker. Finally, despite normal lung volume, Tgfbi-null lungs displayed diminished elastic recoil and gas exchange efficiency. Combined, these data demonstrate that initial suppression of the TGF-β signaling apparatus, as well as loss of key TGF-β effectors (like TGFBI), underlies early alveolar structural defects, as well as long-lasting functional deficits routinely observed in chronic lung disease of infancy patients. These studies underline the complex (and often contradictory) role of TGF-β and indicate a need to design studies to associate alterations with initial appearance of phenotypical changes suggestive of bronchopulmonary dysplasia.
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Affiliation(s)
- Shawn K Ahlfeld
- HB Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana
| | - Jian Wang
- HB Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana
| | - Yong Gao
- HB Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana
| | - Paige Snider
- HB Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana
| | - Simon J Conway
- HB Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana.
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7
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Mishra A, Stueckle TA, Mercer RR, Derk R, Rojanasakul Y, Castranova V, Wang L. Identification of TGF-β receptor-1 as a key regulator of carbon nanotube-induced fibrogenesis. Am J Physiol Lung Cell Mol Physiol 2015; 309:L821-33. [PMID: 26472812 DOI: 10.1152/ajplung.00002.2015] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2015] [Accepted: 08/18/2015] [Indexed: 11/22/2022] Open
Abstract
Carbon nanotubes (CNTs) induce rapid interstitial lung fibrosis, but the underlying mechanisms are unclear. Previous studies indicated that the ability of CNTs to penetrate lung epithelium, enter interstitial tissue, and stimulate fibroblasts to produce collagen matrix is important to lung fibrosis. In this study, we investigated the activation of transforming growth factor-β receptor-1 [TGF-β R1; i.e., activin receptor-like kinase 5 (ALK5) receptor] and TGF-β/Smad signaling pathway in CNT-induced collagen production in human lung fibroblasts. Human lung fibroblasts and epithelial cells were exposed to low, physiologically relevant concentrations (0.02-0.6 μg/cm(2)) of single-walled CNTs (SWCNT) and multiwalled CNTs (MWCNT) in culture and analyzed for collagen, TGF-β1, TGF-β R1, and SMAD proteins by Western blotting and immunofluorescence. Chemical inhibition of ALK5 and short-hairpin (sh) RNA targeting of TGF-β R1 and Smad2 were used to probe the fibrogenic mechanism of CNTs. Both SWCNT and MWCNT induced an overexpression of TGF-β1, TGF-β R1 and Smad2/3 proteins in lung fibroblasts compared with vehicle or ultrafine carbon black-exposed controls. SWCNT- and MWCNT-induced collagen production was blocked by ALK5 inhibitor or shRNA knockdown of TGF-β R1 and Smad2. Our results indicate the critical role of TGF-β R1/Smad2/3 signaling in CNT-induced fibrogenesis by upregulating collagen production in lung fibroblasts. This novel finding may aid in the design of mechanism-based risk assessment and development of rapid screening tests for nanomaterial fibrogenicity.
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Affiliation(s)
- Anurag Mishra
- Health Effects Laboratory Division (HELD), National Institute for Occupational Safety and Health, Morgantown, West Virginia; and Department of Pharmaceutical Sciences, West Virginia University, Morgantown, West Virginia
| | - Todd A Stueckle
- Health Effects Laboratory Division (HELD), National Institute for Occupational Safety and Health, Morgantown, West Virginia; and Department of Pharmaceutical Sciences, West Virginia University, Morgantown, West Virginia
| | - Robert R Mercer
- Health Effects Laboratory Division (HELD), National Institute for Occupational Safety and Health, Morgantown, West Virginia; and
| | - Raymond Derk
- Health Effects Laboratory Division (HELD), National Institute for Occupational Safety and Health, Morgantown, West Virginia; and
| | - Yon Rojanasakul
- Department of Pharmaceutical Sciences, West Virginia University, Morgantown, West Virginia
| | - Vincent Castranova
- Department of Pharmaceutical Sciences, West Virginia University, Morgantown, West Virginia
| | - Liying Wang
- Health Effects Laboratory Division (HELD), National Institute for Occupational Safety and Health, Morgantown, West Virginia; and Department of Pharmaceutical Sciences, West Virginia University, Morgantown, West Virginia
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8
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Abstract
Bone morphogenetic proteins (BMPs), together with the eponymous transforming growth factor (TGF) β and the Activins form the TGFβ superfamily of ligands. This protein family comprises more than 30 structurally highly related proteins, which determine formation, maintenance, and regeneration of tissues and organs. Their importance for the development of multicellular organisms is evident from their existence in all vertebrates as well as nonvertebrate animals. From their highly specific functions in vivo either a strict relation between a particular ligand and its cognate cellular receptor and/or a stringent regulation to define a distinct temperospatial expression pattern for the various ligands and receptor is expected. However, only a limited number of receptors are found to serve a large number of ligands thus implicating highly promiscuous ligand-receptor interactions instead. Since in tissues a multitude of ligands are often found, which signal via a highly overlapping set of receptors, this raises the question how such promiscuous interactions between different ligands and their receptors can generate concerted and highly specific cellular signals required during embryonic development and tissue homeostasis.
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Affiliation(s)
- Thomas D Mueller
- Department Plant Physiology and Biophysics, Julius-von-Sachs Institute of the University Wuerzburg, Wuerzburg, Germany.
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9
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Wang P, Nie X, Wang Y, Li Y, Ge C, Zhang L, Wang L, Bai R, Chen Z, Zhao Y, Chen C. Multiwall carbon nanotubes mediate macrophage activation and promote pulmonary fibrosis through TGF-β/Smad signaling pathway. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2013; 9:3799-3811. [PMID: 23650105 DOI: 10.1002/smll.201300607] [Citation(s) in RCA: 105] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2013] [Indexed: 06/02/2023]
Abstract
Multiwall carbon nanotubes (MWCNTs) have been widely used in many disciplines due to their unique physical and chemical properties, but have also raised great concerns about their possible negative health impacts, especially through occupational exposure. Although recent studies have demonstrated that MWCNTs induce granuloma formation and/or fibrotic responses in the lungs of rats or mice, their cellular and molecular mechanisms remain largely unaddressed. Here, it is reported that the TGF-β/Smad signaling pathway can be activated by MWCNTs and play a critical role in MWCNT-induced pulmonary fibrosis. Firstly, in vivo data show that spontaneously hypertensive (SH) rats administered long MWCNTs (20-50 μm) but not short MWCNTs (0.5-2 μm) exhibit increased fibroblast proliferation, collagen deposition and granuloma formation in lung tissue. Secondly, the in vivo experiments also indicate that only long MWCNTs can significantly activate macrophages and increase the production of transforming growth factor (TGF)-β1, which induces the phosphorylation of Smad2 and then the expression of collagen I/III and extracellular matrix (ECM) protease inhibitors in lung tissues. Finally, the present in vitro studies further demonstrate that the TGF-β/Smad signaling pathway is indeed necessary for the expression of collagen III in fibroblast cells. Together, these data demonstrate that MWCNTs stimulate pulmonary fibrotic responses such as fibroblast proliferation and collagen deposition in a TGF-β/Smad-dependent manner. These observations also suggest that tube length acts as an important factor in MWCNT-induced macrophage activation and subsequent TGF-β1 secretion. These in vivo and in vitro studies further highlight the potential adverse health effects that may occur following MWCNT exposure and provide a better understanding of the cellular and molecular mechanisms by which MWCNTs induce pulmonary fibrotic reactions.
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Affiliation(s)
- Peng Wang
- CAS Key Laboratory for Biomedical Effects of Nanomaterials & Nanosafety, National Center for Nanoscience and Technology, Beijing 100190, China
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10
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Abstract
During the development of the pulmonary vasculature in the fetus, many structural and functional changes occur to prepare the lung for the transition to air breathing. The development of the pulmonary circulation is genetically controlled by an array of mitogenic factors in a temporo-spatial order. With advancing gestation, pulmonary vessels acquire increased vasoreactivity. The fetal pulmonary vasculature is exposed to a low oxygen tension environment that promotes high intrinsic myogenic tone and high vasocontractility. At birth, a dramatic reduction in pulmonary arterial pressure and resistance occurs with an increase in oxygen tension and blood flow. The striking hemodynamic differences in the pulmonary circulation of the fetus and newborn are regulated by various factors and vasoactive agents. Among them, nitric oxide, endothelin-1, and prostaglandin I2 are mainly derived from endothelial cells and exert their effects via cGMP, cAMP, and Rho kinase signaling pathways. Alterations in these signaling pathways may lead to vascular remodeling, high vasocontractility, and persistent pulmonary hypertension of the newborn.
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Affiliation(s)
- Yuansheng Gao
- Department of Physiology and Pathophysiology, Peking University, Health Science Center, Beijing, China; and Department of Pediatrics, University of Illinois, College of Medicine at Chicago, Chicago, Illinois
| | - J. Usha Raj
- Department of Physiology and Pathophysiology, Peking University, Health Science Center, Beijing, China; and Department of Pediatrics, University of Illinois, College of Medicine at Chicago, Chicago, Illinois
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11
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Sullivan DE, Ferris M, Nguyen H, Abboud E, Brody AR. TNF-alpha induces TGF-beta1 expression in lung fibroblasts at the transcriptional level via AP-1 activation. J Cell Mol Med 2010. [PMID: 20141610 DOI: 10.1111/j.1582-4934.2008.00647.x] [Citation(s) in RCA: 120] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Tumour necrosis factor-alpha (TNF-alpha) and transforming growth factor-beta(1) (TGF-beta(1)) are peptides with multiple biological activities that influence neoplastic, immunologic and fibroproliferative diseases. There are clear interrelationships and overlap between the actions of TNF-alpha and TGF-beta(1) in lung fibrosis; therefore, we postulated that TNF-alpha may play a significant role in regulating TGF-beta(1) expression in lungs. We recently reported that TNF-alpha activates the extracellular regulated kinase (ERK)-specific pathway in fibroblasts resulting in stabilization of TGF-beta(1) mRNA and increased expression of TGF-beta(1). In the current study, we further investigated the molecular mechanisms involved in TNF-alpha regulation of TGF-beta(1) expression. Nuclear run-on assays showed that treatment of Swiss 3T3 fibroblasts with TNF-alpha increased transcription of the TGF-beta(1) gene in an ERK independent manner. Pre-treatment with the activator protein-1 (AP-1) inhibitor curcumin attenuated TNF-alpha induced transcription of the TGF-beta(1) gene. TNF-alpha induced increased levels of c-Jun and C-Fos in the nucleus accompanied by phosphorylation of c-Jun. In electrophoretic mobility shift assays, AP-1 binding to an AP-1 binding site found within the TGF-beta(1) promoter was increased in nuclear extracts from Swiss 3T3 fibroblasts treated with TNF-alpha. Together, these results suggest that TNF-alpha induces expression and DNA binding of AP-1 resulting in increased transcription of the TGF-beta(1) gene. It is essential to know which transcription pathways are activated because of the wide distribution of TNF-alpha and TGF-beta(1), the general lack of effective treatments for fibroproliferative disease and the possibility that targeting the correct transcription factors could be palliative.
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Affiliation(s)
- Deborah E Sullivan
- Department of Microbiology and Immunology, Biomedical Sciences Graduate Program, Tulane University School of Medicine, New Orleans, LA, USA
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12
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Sullivan DE, Ferris M, Nguyen H, Abboud E, Brody AR. TNF-alpha induces TGF-beta1 expression in lung fibroblasts at the transcriptional level via AP-1 activation. J Cell Mol Med 2010; 13:1866-76. [PMID: 20141610 DOI: 10.1111/j.1582-4934.2009.00647.x] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Tumour necrosis factor-alpha (TNF-alpha) and transforming growth factor-beta(1) (TGF-beta(1)) are peptides with multiple biological activities that influence neoplastic, immunologic and fibroproliferative diseases. There are clear interrelationships and overlap between the actions of TNF-alpha and TGF-beta(1) in lung fibrosis; therefore, we postulated that TNF-alpha may play a significant role in regulating TGF-beta(1) expression in lungs. We recently reported that TNF-alpha activates the extracellular regulated kinase (ERK)-specific pathway in fibroblasts resulting in stabilization of TGF-beta(1) mRNA and increased expression of TGF-beta(1). In the current study, we further investigated the molecular mechanisms involved in TNF-alpha regulation of TGF-beta(1) expression. Nuclear run-on assays showed that treatment of Swiss 3T3 fibroblasts with TNF-alpha increased transcription of the TGF-beta(1) gene in an ERK independent manner. Pre-treatment with the activator protein-1 (AP-1) inhibitor curcumin attenuated TNF-alpha induced transcription of the TGF-beta(1) gene. TNF-alpha induced increased levels of c-Jun and C-Fos in the nucleus accompanied by phosphorylation of c-Jun. In electrophoretic mobility shift assays, AP-1 binding to an AP-1 binding site found within the TGF-beta(1) promoter was increased in nuclear extracts from Swiss 3T3 fibroblasts treated with TNF-alpha. Together, these results suggest that TNF-alpha induces expression and DNA binding of AP-1 resulting in increased transcription of the TGF-beta(1) gene. It is essential to know which transcription pathways are activated because of the wide distribution of TNF-alpha and TGF-beta(1), the general lack of effective treatments for fibroproliferative disease and the possibility that targeting the correct transcription factors could be palliative.
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Affiliation(s)
- Deborah E Sullivan
- Department of Microbiology and Immunology, Biomedical Sciences Graduate Program, Tulane University School of Medicine, New Orleans, LA, USA
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13
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Buday A, Orsy P, Godó M, Mózes M, Kökény G, Lacza Z, Koller A, Ungvári Z, Gross ML, Benyó Z, Hamar P. Elevated systemic TGF-beta impairs aortic vasomotor function through activation of NADPH oxidase-driven superoxide production and leads to hypertension, myocardial remodeling, and increased plaque formation in apoE(-/-) mice. Am J Physiol Heart Circ Physiol 2010; 299:H386-95. [PMID: 20511416 DOI: 10.1152/ajpheart.01042.2009] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The role of circulating, systemic TGF-beta levels in endothelial function is not clear. TGF-beta(1) may cause endothelial dysfunction in apolipoprotein E-deficient (apoE(-/-)) mice via stimulation of reactive oxygen species (ROS) production by the NADPH oxidase (NOX) system and aggravate aortic and heart remodeling and hypertension. Thoracic aorta (TA) were isolated from 4-mo-old control (C57Bl/6), apoE(-/-), TGF-beta(1)-overexpressing (TGFbeta(1)), and crossbred apoE(-/-) x TGFbeta(1) mice. Endothelium-dependent relaxation was measured before and after incubation with apocynin (NOX inhibitor) or superoxide dismutase (SOD; ROS scavenger). Superoxide production within the vessel wall was determined by dihydroethidine staining under confocal microscope. In 8-mo-old mice, aortic and myocardial morphometric changes, plaque formation by en face fat staining, and blood pressure were determined. Serum TGF-beta(1) levels (ELISA) were elevated in TGFbeta(1) mice without downregulation of TGF-beta-I receptor (immunohistochemistry). In the aortic wall, superoxide production was enhanced and NO-dependent relaxation diminished in apoE(-/-) x TGFbeta(1) mice but improved significantly after apocynin or SOD. Myocardial capillary density was reduced, fibrocyte density increased, aortic wall was thicker, combined lesion area was greater, and blood pressure was higher in the apoE(-/-) x TGFbeta vs. C57Bl/6 mice. Our results demonstrate that elevated circulating TGF-beta(1) causes endothelial dysfunction through NOX activation-induced oxidative stress, accelerating atherosclerosis and hypertension in apoE(-/-) mice. These findings may provide a mechanism explaining accelerated atherosclerosis in patients with elevated plasma TGFbeta(1).
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Affiliation(s)
- Anna Buday
- Institute of Pathophysiology, Dept. of Medicine, Semmelweis Univ., Budapest, 1089 Nagyvárad tér 4, Hungary
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14
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Bottoms SE, Howell JE, Reinhardt AK, Evans IC, McAnulty RJ. Tgf-Beta isoform specific regulation of airway inflammation and remodelling in a murine model of asthma. PLoS One 2010; 5:e9674. [PMID: 20300191 PMCID: PMC2837347 DOI: 10.1371/journal.pone.0009674] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2009] [Accepted: 02/22/2010] [Indexed: 01/01/2023] Open
Abstract
The TGF-β family of mediators are thought to play important roles in the regulation of inflammation and airway remodelling in asthma. All three mammalian isoforms of TGF-β, TGF-β1–3, are expressed in the airways and TGF-β1 and -β2 are increased in asthma. However, there is little information on the specific roles of individual TGF-β isoforms. In this study we assess the roles of TGF-β1 and TGF-β2 in the regulation of allergen-induced airway inflammation and remodelling associated with asthma, using a validated murine model of ovalbumin sensitization and challenge, and isoform specific TGF-β neutralising antibodies. Antibodies to both isoforms inhibited TGF-β mediated Smad signalling. Anti-TGF-β1 and anti-TGF-β2 inhibited ovalbumin-induced sub-epithelial collagen deposition but anti-TGF-β1 also specifically regulated airway and fibroblast decorin deposition by TGF-β1. Neither antibody affected the allergen-induced increase in sub-epithelial fibroblast-like cells. Anti- TGF-β1 also specifically inhibited ovalbumin-induced increases in monocyte/macrophage recruitment. Whereas, both TGF-β1 and TGF-β2 were involved in regulating allergen-induced increases in eosinophil and lymphocyte numbers. These data show that TGF-β1 and TGF-β2 exhibit a combination of specific and shared roles in the regulation of allergen-induced airway inflammation and remodelling. They also provide evidence in support of the potential for therapeutic regulation of specific subsets of cells and extracellular matrix proteins associated with inflammation and remodelling in airway diseases such as asthma and COPD, as well as other fibroproliferative diseases.
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Affiliation(s)
- Stephen E. Bottoms
- Lung Pathobiology Group, Centre for Respiratory Research, University College London, London, United Kingdom
| | - Jane E. Howell
- Lung Pathobiology Group, Centre for Respiratory Research, University College London, London, United Kingdom
| | - Alistair K. Reinhardt
- Lung Pathobiology Group, Centre for Respiratory Research, University College London, London, United Kingdom
| | - Iona C. Evans
- Lung Pathobiology Group, Centre for Respiratory Research, University College London, London, United Kingdom
| | - Robin J. McAnulty
- Lung Pathobiology Group, Centre for Respiratory Research, University College London, London, United Kingdom
- * E-mail: *
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15
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Warburton D, El-Hashash A, Carraro G, Tiozzo C, Sala F, Rogers O, De Langhe S, Kemp PJ, Riccardi D, Torday J, Bellusci S, Shi W, Lubkin SR, Jesudason E. Lung organogenesis. Curr Top Dev Biol 2010; 90:73-158. [PMID: 20691848 DOI: 10.1016/s0070-2153(10)90003-3] [Citation(s) in RCA: 297] [Impact Index Per Article: 21.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Developmental lung biology is a field that has the potential for significant human impact: lung disease at the extremes of age continues to cause major morbidity and mortality worldwide. Understanding how the lung develops holds the promise that investigators can use this knowledge to aid lung repair and regeneration. In the decade since the "molecular embryology" of the lung was first comprehensively reviewed, new challenges have emerged-and it is on these that we focus the current review. Firstly, there is a critical need to understand the progenitor cell biology of the lung in order to exploit the potential of stem cells for the treatment of lung disease. Secondly, the current familiar descriptions of lung morphogenesis governed by growth and transcription factors need to be elaborated upon with the reinclusion and reconsideration of other factors, such as mechanics, in lung growth. Thirdly, efforts to parse the finer detail of lung bud signaling may need to be combined with broader consideration of overarching mechanisms that may be therapeutically easier to target: in this arena, we advance the proposal that looking at the lung in general (and branching in particular) in terms of clocks may yield unexpected benefits.
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Affiliation(s)
- David Warburton
- The Saban Research Institute, Childrens Hospital Los Angeles, Los Angeles, California, USA
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16
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Leppäranta O, Myllärniemi M, Salmenkivi K, Kinnula VL, Keski-Oja J, Koli K. Reduced Phosphorylation of the TGF-β Signal Transducer Smad2 in Emphysematous Human Lung. COPD 2009; 6:234-41. [DOI: 10.1080/15412550903049173] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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17
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Nakamura Y, Miyata M, Shimokawa N, Ohnuma Y, Katoh R, Ogawa H, Okumura K, Nakao A. House dust mite allergen Der f 1 can induce the activation of latent TGF-beta via its protease activity. FEBS Lett 2009; 583:2088-92. [PMID: 19467230 DOI: 10.1016/j.febslet.2009.05.030] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2009] [Accepted: 05/18/2009] [Indexed: 10/20/2022]
Abstract
A major house dust mite allergen Der f 1 belongs to the papain-like cysteine protease family. This study investigated whether Der f 1 can cleave the latency-associated peptide (LAP) of transforming growth factor (TGF)-beta via its proteolytic activity and activate latent TGF-beta. We found that Der f 1 can cleave LAP and induce the activation of latent TGF-beta, leading to functional Smad signaling. Importantly, these actions of Der f 1 were inhibited by cysteine protease inhibitor E64 or inactivation of the protease activity by heat. Thus, latent TGF-beta may be a direct target of Der f 1 protease activity.
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Affiliation(s)
- Yuki Nakamura
- Department of Immunology, Faculty of Medicine, University of Yamanashi, Chuo, Yamanashi, Japan
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18
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Anthwal N, Chai Y, Tucker AS. The role of transforming growth factor-beta signalling in the patterning of the proximal processes of the murine dentary. Dev Dyn 2008; 237:1604-13. [PMID: 18498113 DOI: 10.1002/dvdy.21567] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
The evolution of the novel mammalian jaw articulation has resulted in an increased complexity of the dentary bone, reflecting the multiple roles it now fulfils as the primary bone of the mandible. Signalling through the Tgf-beta type II receptor is important in the development and patterning of the proximal dentary processes, especially the angular process, and secondary cartilages. We show that expression of Tgf-beta2 is associated with the developing angular process, and that the connective tissue marker Scleraxis is co-expressed with Tgf-beta2. Scleraxis expression is lost around the angular process of Tgfbr2 conditional knockouts and Tgf-beta signalling can induce Scleraxis expression in explant culture. Induction of secondary cartilages in explant culture can be prevented by inhibition of Tgf-beta signalling. This study suggests that the proper development of the processes and their secondary cartilages relies on both Tgf-beta signalling and mechanical forces working in concert.
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Affiliation(s)
- Neal Anthwal
- Department of Craniofacial Development, Kings College London, London, United Kingdom.
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19
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Alejandre-Alcázar MA, Michiels-Corsten M, Vicencio AG, Reiss I, Ryu J, de Krijger RR, Haddad GG, Tibboel D, Seeger W, Eickelberg O, Morty RE. TGF-beta signaling is dynamically regulated during the alveolarization of rodent and human lungs. Dev Dyn 2008; 237:259-69. [PMID: 18095342 DOI: 10.1002/dvdy.21403] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Although transforming growth factor-beta (TGF-beta) signaling negatively regulates branching morphogenesis in early lung development, few studies to date have addressed the role of this family of growth factors during late lung development. We describe here that the expression, tissue localization, and activity of components of the TGF-beta signaling machinery are dynamically regulated during late lung development in the mouse and human. Pronounced changes in the expression and localization of the TGF-beta receptors Acvrl1, Tgfbr1, Tgfbr2, Tgfbr3, and endoglin, and the intracellular messengers Smad2, Smad3, Smad4, Smad6, and Smad7 were noted as mouse and human lungs progressed through the canalicular, saccular, and alveolar stages of development. TGF-beta signaling, assessed by phosphorylation of Smad2, was detected in the vascular and airway smooth muscle, as well as the alveolar and airway epithelium throughout late lung development. These data suggest that active TGF-beta signaling is required for normal late lung development.
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Affiliation(s)
- Miguel A Alejandre-Alcázar
- Department of Internal Medicine, University of Giessen Lung Center, Justus Liebig University, Giessen, Germany
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20
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Ambalavanan N, Nicola T, Hagood J, Bulger A, Serra R, Murphy-Ullrich J, Oparil S, Chen YF. Transforming growth factor-beta signaling mediates hypoxia-induced pulmonary arterial remodeling and inhibition of alveolar development in newborn mouse lung. Am J Physiol Lung Cell Mol Physiol 2008; 295:L86-95. [PMID: 18487357 DOI: 10.1152/ajplung.00534.2007] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Hypoxia causes abnormal neonatal pulmonary artery remodeling (PAR) and inhibition of alveolar development (IAD). Transforming growth factor (TGF)-beta is an important regulator of lung development and repair from injury. We tested the hypothesis that inhibition of TGF-beta signaling attenuates hypoxia-induced PAR and IAD. Mice with an inducible dominant-negative mutation of the TGF-beta type II receptor (DNTGFbetaRII) and nontransgenic wild-type (WT) mice were exposed to hypoxia (12% O(2)) or air from birth to 14 days of age. Expression of DNTGFbetaRII was induced by 20 microg/g ZnSO(4) given intraperitoneally daily from birth. PAR, IAD, cell proliferation, and expression of extracellular matrix (ECM) proteins were assessed. In WT mice, hypoxia led to thicker, more muscularized resistance pulmonary arteries and impaired alveolarization, accompanied by increases in active TGF-beta and phosphorylated Smad2. Hypoxia-induced PAR and IAD were greatly attenuated in DNTGFbetaRII mice given ZnSO(4) compared with WT control mice and DNTGFbetaRII mice not given ZnSO(4). The stimulatory effects of hypoxic exposure on pulmonary arterial cell proliferation and lung ECM proteins were abrogated in DNTGFbetaRII mice given ZnSO(4). These data support the conclusion that TGF-beta plays an important role in hypoxia-induced pulmonary vascular adaptation and IAD in the newborn animal model.
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Affiliation(s)
- Namasivayam Ambalavanan
- Department of Pediatrics, University of Alabama at Birmingham, Birmingham, Alabama 35233, USA.
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21
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Chen H, Zhuang F, Liu YH, Xu B, Del Moral P, Deng W, Chai Y, Kolb M, Gauldie J, Warburton D, Moses HL, Shi W. TGF-beta receptor II in epithelia versus mesenchyme plays distinct roles in the developing lung. Eur Respir J 2008; 32:285-95. [PMID: 18321928 DOI: 10.1183/09031936.00165407] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Transforming growth factor (TGF)-beta signalling plays important roles in regulating lung development. However, the specific regulatory functions of TGF-beta signalling in developing lung epithelial versus mesenchymal cells are still unknown. By immunostaining, the expression pattern of the TGF-beta type II receptor (TbetaRII) was first determined in the developing mouse lung. The functions of TbetaRII in developing lung were then determined by conditionally knocking out TbetaRII in the lung epithelium of floxed-TbetaRII/surfactant protein C-reverse tetracycline transactivator/TetO-Cre mice versus mesenchyme of floxed-TbetaRII/Dermo1-Cre mice. TbetaRII was expressed only in distal airway epithelium at early gestation (embryonic day (E)11.5), but in both airway epithelium and mesenchyme from mid-gestation (E14.5) to post-natal day 14. Abrogation of TbetaRII in mouse lung epithelium resulted in retardation of post-natal lung alveolarisation, with markedly decreased type I alveolar epithelial cells, while no abnormality in prenatal lung development was observed. In contrast, blockade of TbetaRII in mesoderm-derived tissues, including lung mesenchyme, resulted in mildly abnormal lung branching and reduced cell proliferation after mid-gestation, accompanied by multiple defects in other organs, including diaphragmatic hernia. The primary lung branching defect was verified in embryonic lung explant culture. The novel findings of the present study suggest that transforming growth factor-beta type II receptor-mediated transforming growth factor-beta signalling plays distinct roles in lung epithelium versus mesenchyme to differentially control specific stages of lung development.
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Affiliation(s)
- H Chen
- Developmental Biology Program, Dept of Surgery, Childrens Hospital Los Angeles, 4650 Sunset Blvd, MS 35, Los Angeles, CA 90027, USA
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22
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Austin AF, Compton LA, Love JD, Brown CB, Barnett JV. Primary and immortalized mouse epicardial cells undergo differentiation in response to TGFbeta. Dev Dyn 2008; 237:366-76. [PMID: 18213583 DOI: 10.1002/dvdy.21421] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Cells derived from the epicardium are required for coronary vessel development. Transforming growth factor beta (TGFbeta) induces loss of epithelial character and smooth muscle differentiation in chick epicardial cells. Here, we show that epicardial explants from embryonic day (E) 11.5 mouse embryos incubated with TGFbeta1 or TGFbeta2 lose epithelial character and undergo smooth muscle differentiation. To further study TGFbeta Signaling, we generated immortalized mouse epicardial cells. Cells from E10.5, 11.5, and 13.5 formed tightly packed epithelium and expressed the epicardial marker Wilm's tumor 1 (WT1). TGFbeta induced the loss of zonula occludens-1 (ZO-1) and the appearance of SM22alpha and calponin consistent with smooth muscle differentiation. Inhibition of activin receptor-like kinase (ALK) 5 or p160 rho kinase activity prevented the effects of TGFbeta while inhibition of p38 mitogen activated protein (MAP) kinase did not. These data demonstrate that TGFbeta induces epicardial cell differentiation and that immortalized epicardial cells provide a suitable model for differentiation.
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Affiliation(s)
- Anita F Austin
- Department of Pharmacology, Vanderbilt University Medical Center, Nashville, Tennessee 37232-6600, USA
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23
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Bossé Y, Thompson C, McMahon S, Dubois CM, Stankova J, Rola-Pleszczynski M. Leukotriene D4-induced, epithelial cell-derived transforming growth factor beta1 in human bronchial smooth muscle cell proliferation. Clin Exp Allergy 2007; 38:113-21. [PMID: 18028462 DOI: 10.1111/j.1365-2222.2007.02873.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
BACKGROUND Cysteinyl-leukotrienes (cys-LTs) orchestrate many pathognomonic features of asthma in animal models of allergic airway inflammation, including bronchial smooth muscle cell (BSMC) hyperplasia. However, because cys-LTs alone do not induce mitogenesis in monocultures of human BSMC, the effect observed in vivo seemingly involves indirect mechanisms, which are still undefined. OBJECTIVE This study aims to investigate the regulatory role of leukotriene (LT)D(4) on TGF-beta1 expression in airway epithelial cells and the consequence of this interplay on BSMC proliferation. METHODS HEK293 cells stably transfected with cys-LT receptor 1 (CysLT1) (293LT1) were stimulated with LTD(4) and TGF-beta1 mRNA and protein expression was measured using Northern blot and ELISA, respectively. Conditioned medium (CM) harvested from LTD(4)-treated cells was then assayed for its proliferative effect on primary human BSMC. TGF-beta1 mRNA expression was also determined in tumoural type II pneumocytes A549 and in normal human bronchial epithelial cells (NHBE) following LTD(4) stimulation. RESULTS The results demonstrated that LTD(4)-induced TGF-beta1 mRNA production in a time- and concentration-dependent manner in 293LT1. TGF-beta1 secretion was also up-regulated and CM from LTD(4)-treated 293LT1 was shown to increase BSMC proliferation in a TGF-beta1-dependent manner. The increased expression of TGF-beta1 mRNA by LTD(4) also occured in A549 and NHBE cells via a CysLT1-dependent mechanism. CONCLUSION In conclusion, elevated expression of cys-LTs in asthmatic airways might contribute to BSMC hyperplasia and concomitant clinical features of asthma such as airway hyperresponsiveness via a paracrine loop involving TGF-beta1 production by airway epithelial cells.
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Affiliation(s)
- Y Bossé
- Department of Pediatrics, Immunology Division, Faculty of Medicine, Université de Sherbrooke, Sherbrooke, QC, Canada
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24
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Bossé Y, Rola-Pleszczynski M. Controversy surrounding the increased expression of TGF beta 1 in asthma. Respir Res 2007; 8:66. [PMID: 17892594 PMCID: PMC2078588 DOI: 10.1186/1465-9921-8-66] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2007] [Accepted: 09/24/2007] [Indexed: 01/18/2023] Open
Abstract
Asthma is a waxing and waning disease that leads to structural changes in the airways, such as subepithelial fibrosis, increased mass of airway smooth muscle and epithelial metaplasia. Such a remodeling of the airways futher amplifies asthma symptoms, but its etiology is unknown. Transforming growth factor β1 is a pleiotropic cytokine involved in many fibrotic, oncologic and immunologic diseases and is believed to play an essential role in airway remodeling that occurs in asthmatic patients. Since it is secreted in an inactive form, the overall activity of this cytokine is not exclusively determined by its level of expression, but also by extensive and complex post-translational mechanisms, which are all importanin modulating the magnitude of the TGFβ1 response. Even if TGFβ1 upregulation in asthma is considered as a dogma by certain investigators in the field, the overall picture of the published litterature is not that clear and the cellular origin of this cytokine in the airways of asthmatics is still a contemporaneous debate. On the other hand, it is becoming clear that TGFβ1 signaling is increased in the lungs of asthmatics, which testifies the increased activity of this cytokine in asthma pathogenesis. The current work is an impartial and exhaustive compilation of the reported papers regarding the expression of TGFβ1 in human asthmatics. For the sake of comparison, several studies performed in animal models of the disease are also included. Inconsistencies observed in human studies are discussed and conclusions as well as trends from the current state of the litterature on the matter are proposed. Finally, the different points of regulation that can affect the amplitude of the TGFβ1 response are briefly revised and the possibility that TGFβ1 is disregulated at another level in asthma, rather than simply in its expression, is highlighted.
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Affiliation(s)
- Ynuk Bossé
- Immunology Division, Department of Pediatrics, Faculty of Medicine, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Marek Rola-Pleszczynski
- Immunology Division, Department of Pediatrics, Faculty of Medicine, Université de Sherbrooke, Sherbrooke, QC, Canada
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25
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Spagnoli A, O'Rear L, Chandler RL, Granero-Molto F, Mortlock DP, Gorska AE, Weis JA, Longobardi L, Chytil A, Shimer K, Moses HL. TGF-beta signaling is essential for joint morphogenesis. ACTA ACUST UNITED AC 2007; 177:1105-17. [PMID: 17576802 PMCID: PMC2064369 DOI: 10.1083/jcb.200611031] [Citation(s) in RCA: 124] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Despite its clinical significance, joint morphogenesis is still an obscure process. In this study, we determine the role of transforming growth factor beta (TGF-beta) signaling in mice lacking the TGF-beta type II receptor gene (Tgfbr2) in their limbs (Tgfbr2(PRX-1KO)). In Tgfbr2(PRX-1KO) mice, the loss of TGF-beta responsiveness resulted in the absence of interphalangeal joints. The Tgfbr2(Prx1KO) joint phenotype is similar to that in patients with symphalangism (SYM1-OMIM185800). By generating a Tgfbr2-green fluorescent protein-beta-GEO-bacterial artificial chromosome beta-galactosidase reporter transgenic mouse and by in situ hybridization and immunofluorescence, we determined that Tgfbr2 is highly and specifically expressed in developing joints. We demonstrated that in Tgfbr2(PRX-1KO) mice, the failure of joint interzone development resulted from an aberrant persistence of differentiated chondrocytes and failure of Jagged-1 expression. We found that TGF-beta receptor II signaling regulates Noggin, Wnt9a, and growth and differentiation factor-5 joint morphogenic gene expressions. In Tgfbr2(PRX-1KO) growth plates adjacent to interphalangeal joints, Indian hedgehog expression is increased, whereas Collagen 10 expression decreased. We propose a model for joint development in which TGF-beta signaling represents a means of entry to initiate the process.
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Affiliation(s)
- Anna Spagnoli
- Department of Pediatrics, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
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26
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Abstract
Chronic obstructive pulmonary disease (COPD) is a condition which is characterized by irreversible airway obstruction due to narrowing of small airways, bronchiolitis, and destruction of the lung parenchyma, emphysema. It is the fourth most common cause of mortality in the world and is expected to be the third most common cause of death by 2020. The main cause of COPD is smoking but other exposures may be of importance. Exposure leads to airway inflammation in which a variety of cells are involved. Besides neutrophil granulocytes, macrophages and lymphocytes, airway epithelial cells are also of particular importance in the inflammatory process and in the development of emphysema. Cell trafficking orchestrated by chemokines and other chamoattractants, the proteinase-antiproteinase system, oxidative stress and airway remodelling are central processes associated with the development of COPD. Recently systemic effects of COPD have attracted attention and the importance of systemic inflammation has been recognized. This seems to have direct therapeutic implications as treatment with inhaled glucocorticosteroids has been shown to influence mortality. The increasing body of knowledge regarding the inflammatory mechanism in COPD will most likely have implications for future therapy and new drugs, specifically aimed at interaction with the inflammatory processes, are currently being developed.
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Affiliation(s)
- Kjell Larsson
- Unit of Lung and Allergy Research, National Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden.
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27
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Abstract
With respect to CD8 effector T cells, interleukin-12 (IL-12) and transforming growth factor beta (TGFbeta) are 2 cytokines that exert opposing effects. IL-12 promotes antitumor immune responses by augmenting activated CD8 T-cell proliferation and interferon-gamma secretion. Conversely, TGFbeta generates a permissive environment for cancer growth, in part by antagonizing the effects of immunomodulatory cytokines, including IL-12. We demonstrate that TGFbeta-resistant T cells are capable of sustaining IL-12-induced mitogenesis and interferon-gamma secretion in a TGFbeta-rich milieu. Furthermore, in 2 murine tumor models associated with high TGFbeta1 levels in the local microenvironment, treatment with IL-12 and adoptively transferred TGFbeta-resistant T cells provided improved survival times. These results suggest that combining IL-12 with TGFbeta neutralization strategies may be effective in enhancing antitumor immune responses.
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MESH Headings
- Animals
- CD4-Positive T-Lymphocytes/immunology
- CD4-Positive T-Lymphocytes/pathology
- CD8-Positive T-Lymphocytes/immunology
- CD8-Positive T-Lymphocytes/pathology
- Cell Line
- Cell Proliferation
- Female
- Immunotherapy, Adoptive
- Interferon-gamma/biosynthesis
- Interleukin-12/immunology
- Interleukin-12/pharmacology
- Male
- Melanoma, Experimental/mortality
- Melanoma, Experimental/pathology
- Melanoma, Experimental/therapy
- Mice
- Mice, Inbred C57BL
- Mice, Transgenic
- Neoplasms, Experimental/mortality
- Neoplasms, Experimental/pathology
- Neoplasms, Experimental/therapy
- Papilloma, Choroid Plexus/mortality
- Papilloma, Choroid Plexus/pathology
- Papilloma, Choroid Plexus/therapy
- Receptors, Transforming Growth Factor beta/genetics
- T-Lymphocytes/immunology
- T-Lymphocytes/transplantation
- Transforming Growth Factor beta1/immunology
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Affiliation(s)
- Timothy M Fan
- Department of Veterinary Clinical Medicine, University of Illinois at Urbana-Champaign, 1008 West Hazelwood Drive, Urbana, IL 61801, USA.
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28
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Abstract
The immune system is organized as a number of distinct lymphoid organs interconnected by recirculating lymphocytes. These organs, such as lymph nodes, spleen, and gut-associated Peyer's patches, are compartmentalized, providing separate niches for T and B cells. In addition, regional compartmentalization of lymphoid organs themselves exists, leading to the distinction between the mucosal and the systemic immune systems. This distinction not only reflects the anatomical localization but also is based on functional differences, with predominant tolerance induction via mucosal routes and immunity seen after systemic antigen exposure. These differences are associated with regional differences in the lymphoid organs and with environmental conditions of the tissues in which the immune system functions. Recirculation patterns of lymphocytes differ between mucosal and systemic lymphoid organs, and more insight into the mechanisms that imprint this behavior has been generated recently. Differences in dendritic cells have been observed between mucosal and systemic sites, and knowledge on how local factors contribute to the immune system is emerging. From our studies on mucosal tolerance in mouse models, it has become evident that regional lymph nodes draining the mucosa are important sites to direct immune responses. Here, we discuss the way regional lymph nodes contribute to the direction of immune responses and what is known about the local factors and cell behavior that form the basis for these differences.
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Affiliation(s)
- Georg Kraal
- Department of Molecular Cell Biology and Immunology, VU University Medical Center, Amsterdam, The Netherlands.
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29
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Perkett EA, Ornatowski W, Poschet JF, Deretic V. Chloroquine normalizes aberrant transforming growth factor beta activity in cystic fibrosis bronchial epithelial cells. Pediatr Pulmonol 2006; 41:771-8. [PMID: 16779853 DOI: 10.1002/ppul.20452] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Cystic fibrosis (CF) remains a fatal progressive disease in spite of the discovery and characterization of the CFTR gene. Transforming growth factor beta (TGF-beta) has been implicated in pathophysiology of CF. Previous reports have shown the trans-Golgi network (TGN) is hyperacdified in CF epithelial cells in culture and that this hyperacidification can be corrected with the membrane permeant weak base, chloroquine. In this study bioactive TGF-beta produced by CF and normal cells was measured using a reporter cell line with a TGF-beta responsive promoter linked to luciferase. Increased levels of TGF-beta were detected in the conditioned media from CF epithelial cells compared to their matched controls-(IB3-1 vs. S9; pCEP-R vs. pCEP, CuFi-4 vs. NuLi-1). Levels of TGF-beta were normalized with chloroquine indicating that the hyperacidification of the TGN of CF cells is responsible for the altered TGF-beta levels.
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Affiliation(s)
- Elizabeth A Perkett
- Department of Pediatrics, University of New Mexico Health Sciences Center, Albuquerque, New Mexico 87131-0001, USA.
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30
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Yamazaki K, Crowe DL, Shuler CF. Hunchback sequence binding protein suppresses mouse TGF-β3 promoter in vitro. Biochem Biophys Res Commun 2006; 346:802-9. [PMID: 16781676 DOI: 10.1016/j.bbrc.2006.05.178] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2006] [Accepted: 05/29/2006] [Indexed: 10/24/2022]
Abstract
Transforming growth factor-beta3 (TGF-beta3) has a specific role in vivo in the patterning of embryonic and tissue-specific gene expression. We have cloned and sequenced the mouse TGF-beta3 5'-flanking region to study the transcriptional regulation of this gene. Promoter fragments were cloned into a promoterless luciferase reporter plasmid to study functional activity in a human skin melanoma cell line A375 (A375). Sequential 5'-deletion encompassing DNA sequences from -2297 to -1003 bp exhibited high promoter activity in A375 cells, whereas the promoter activity decreased to minimal in the -742 to 104 bp regions, suggesting both positive and negative transcriptional regulation in the TGF-beta3 promoter. The fragment containing 1.8 kb had the highest luciferase activity. Characterization of this 1.8 kb 5'-flanking region upstream of the translation start site showed a putative hunchback-binding site consensus sequence. The electrophoretic mobility shift assay (EMSA) and transient transfection experiments showed that the putative hunchback-binding site is functional and regulated TGF-beta3 promoter transcriptional activity. The DNA-complex including the hunchback sequence binding protein (HbSBP) was important for suppression of the promoter activity in A375 cells. Mutation of the hunchback consensus sequence resulted in up to 2-fold higher promoter activity than the wild type construct. There was an absence of HbSBP in other cell lines tested including 3T3 fibroblast and B-16 mouse skin melanoma as determined by EMSA and Western blot analysis. HbSBP may function as a TGF-beta3 gene transcriptional regulator and may be expressed in a cell type-specific manner.
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Affiliation(s)
- Kiyomi Yamazaki
- Center for Craniofacial Molecular Biology, School of Dentistry, University of Southern California, Los Angeles, CA, USA
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Cardoso WV, Lü J. Regulation of early lung morphogenesis: questions, facts and controversies. Development 2006; 133:1611-24. [PMID: 16613830 DOI: 10.1242/dev.02310] [Citation(s) in RCA: 409] [Impact Index Per Article: 22.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
During early respiratory system development, the foregut endoderm gives rise to the tracheal and lung cell progenitors. Through branching morphogenesis, and in coordination with vascular development, a tree-like structure of epithelial tubules forms and differentiates to produce the airways and alveoli. Recent studies have implicated the fibroblast growth factor, sonic hedgehog, bone morphogenetic protein, retinoic acid and Wnt signaling pathways, and various transcription factors in regulating the initial stages of lung development. However, the precise roles of these molecules and how they interact in the developing lung is subject to debate. Here, we review early stages in lung development and highlight questions and controversies regarding their molecular regulation.
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Akiho H, Deng Y, Blennerhassett P, Kanbayashi H, Collins SM. Mechanisms underlying the maintenance of muscle hypercontractility in a model of postinfective gut dysfunction. Gastroenterology 2005; 129:131-41. [PMID: 16012943 DOI: 10.1053/j.gastro.2005.03.049] [Citation(s) in RCA: 118] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND & AIMS Acute gastroenteritis is a strong risk factor for the development of irritable bowel syndrome (IBS). We have developed an animal model in which transient acute infection leads to persistent muscle hypercontractility. Here, we investigate the mechanisms underlying the maintenance of this hypercontractility in the postinfective (PI) state. METHODS Muscle contraction and messenger RNA (mRNA) or protein expression of cytokines were examined from jejunal longitudinal muscle cells of NIH Swiss mice infected with Trichinella spiralis or incubated with or without cytokines. RESULTS During acute infection, interleukin (IL)-4 or IL-13, transforming growth factor (TGF)-beta1, and cyclooxygenase (COX)-2 were increased in the muscle layer ( P < .05). In the PI phase of the model, T helper (Th)2 cytokines returned to normal, but TGF-beta1 remained in the muscle ( P < .05). Exposure of muscle cells to IL-4 or IL-13 increased TGF-beta1 ( P < .01), COX-2 protein, and prostaglandin (PG)E 2 . Exposure of muscle cells to TGF-beta1 increased PGE 2 ( P < .05) and COX-2 protein. Incubation of tissue with IL-4, IL-13, TGF-beta1, or PGE 2 enhanced carbachol-induced muscle cell contractility ( P < .05). COX-2 inhibitor attenuated TGF-beta1-induced muscle hypercontractility ( P < .05). CONCLUSIONS These results support the hypothesis that Th2 cytokines induce muscle hypercontractility during infection by a direct action on smooth muscle. The maintenance of hypercontractility results from Th2 cytokine-induced expression of TGF-beta1 and the subsequent up-regulation of COX-2 and PGE 2 at the level of the smooth muscle cell. We propose that PI gut dysfunction reflects mediator production in the neuromuscular tissues and that this may occur in PI-IBS.
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Affiliation(s)
- Hirotada Akiho
- Intestinal Diseases Research Program, Department of Medicine, McMaster University, Hamilton, Ontario, Canada
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Scherf W, Burdach S, Hansen G. Reduced expression of transforming growth factor beta 1 exacerbates pathology in an experimental asthma model. Eur J Immunol 2005; 35:198-206. [PMID: 15593298 DOI: 10.1002/eji.200425209] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Allergic asthma is characterized by airway hyperreactivity (AHR), eosinophilic airway inflammation and elevated serum IgE levels. T-helper 2 (Th2) cells play a critical role in the pathogenesis of asthma, but the immunological mechanisms that inhibit Th2 cell function in vivo are not well understood. Conflicting results regarding the protective role of Th1 cytokines and TGF-beta in asthma have been reported. To further investigate the role of TGF-beta(1 )in asthma, we examined mice heterozygous for deletion of the TGF-beta(1) gene (TGF-beta(1) (+/-) mice) in a murine asthma model. While TGF-beta(1) (+/-) mice seem phenotypically normal, they express only about 30% of wild type TGF-beta(1) protein levels as shown before. The reduced expression of TGF-beta(1) is accompanied by a strikingly increased eosinophilic inflammation and mucus secretion in response to ovalbumin (OVA) sensitization. Moreover, TGF-beta(1) (+/-) mice develop significantly enhanced Th2-cytokine levels, decreased IFN-gamma production and increased levels of OVA-specific IgE in serum. In contrast, AHR in response to methacholine is not altered significantly. Our data demonstrate that reduced expression of TGF-beta(1) exacerbates pathology in an experimental asthma model and support the view that the elevated levels of TGF-beta(1) in asthmatic airways might be, at least in part, a result of anti-inflammatory compensation by this cytokine.
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Affiliation(s)
- Wiebke Scherf
- Department of Pediatrics, Division of Allergy and Pulmonology, Martin-Luther-University Halle-Wittenberg, D-06120 Halle, Germany
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van Helvoort JMLM, Samsom JN, Chantry D, Jansen W, Schadee-Eestermans I, Thepen T, Mebius RE, Kraal G. Preferential expression of IgG2b in nose draining cervical lymph nodes and its putative role in mucosal tolerance induction. Allergy 2004; 59:1211-8. [PMID: 15461604 DOI: 10.1111/j.1398-9995.2004.00510.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Induction of intranasal tolerance prevents the body from eliciting unwanted immune responses against harmless antigens that enter the body through the nasal mucosa. To study the intrinsic capacities of the cervical, nose draining lymph nodes (CLN), which are essential for tolerance induction, genes that are differentially expressed in CLN and not in peripheral lymph nodes (PLN) were characterized. The gene that is predominantly overexpressed in CLN codes for IgG2b. This is confirmed by a higher percentage of IgG2b+ B220+ cells in CLN compared with any PLN. However, this predominance of IgG2b-positive B cells in the CLN is not specific for the lymph node itself but rather determined by the region drained by lymph nodes at the cervical site, as transplanted PLN at these locations show a comparable predominance. It was demonstrated that IgG2b, when compared with IgG1, led to differential activation of dendritic cells (DC) through Fc receptor signalling. The results point to a unique local combination of cells and factors in the nose draining CLN leading to highly specialized immune reactivity. The results point out that predominance of a distinct IgG isotype in a lymphoid environment may lead to highly specialized immune reactivity.
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Affiliation(s)
- J M L M van Helvoort
- Department of Molecular Cell Biology and Immunology, Vrije Universiteit Medical Center, Amsterdam, The Netherlands
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Kumar RK, Herbert C, Foster PS. Expression of growth factors by airway epithelial cells in a model of chronic asthma: regulation and relationship to subepithelial fibrosis. Clin Exp Allergy 2004; 34:567-75. [PMID: 15080809 DOI: 10.1111/j.1365-2222.2004.1917.x] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
BACKGROUND Growth factors produced by airway epithelial cells may be important in the pathogenesis of subepithelial fibrosis, a distinctive lesion of chronic human asthma. OBJECTIVE To examine the relationship between the development of subepithelial fibrosis and the expression of transforming growth factor-beta 1 (TGF-beta 1) and ligands for the epidermal growth factor receptor. METHODS BALB/c mice sensitized to ovalbumin were chronically challenged by inhalation of low levels of antigen, leading to development of subepithelial fibrosis and other changes of airway wall remodelling. Growth factor expression was assessed by immunohistochemistry and enzyme immunoassay. RESULTS Allergic sensitization directly correlated with airway epithelial expression of both the cleaved, potentially biologically active form of TGF-beta 1 and of amphiregulin in response to allergen challenge. Accumulation of TGF-beta 1 was related to remodelling of the airway wall in chronic asthma, whereas expression of amphiregulin did not exhibit a similar relationship. Production of epithelial cell-derived TGF-beta 1 appeared to be regulated by IL-13, while both IL-13 and CD4(+) T cells regulated accumulation of TGF-beta 1. In contrast to results reported in high-level exposure models of airway fibrosis, eosinophils did not appear to be a significant source of TGF-beta 1. CONCLUSION Airway epithelial cell-derived TGF-beta 1 has a potentially crucial role in the development of airway wall remodelling in asthma. Immunological mechanisms may regulate the release and accumulation of TGF-beta 1.
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Affiliation(s)
- R K Kumar
- Department of Pathology, University of New South Wales, Sydney, Australia.
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Abstract
Transforming growth factor (TGF) beta plays an important role in normal pulmonary morphogenesis and function and in the pathogenesis of lung disease. The effect of TGFbeta is regulated via a selective pathway of TGFbeta synthesis and signaling that involves activation of latent TGFbeta, specific TGFbeta receptors, and intracellular signaling via Smad molecules. All three isoforms of TGFbeta are expressed at high levels during normal lung development, being particularly important for branching morphogenesis and epithelial cell differentiation with maturation of surfactant synthesis. Small amounts of TGFbeta are still present in the adult lung, and TGFbeta is involved in normal tissue repair following lung injury. However, in a variety of forms of pulmonary pathology, the expression of TGFbeta is increased. These include chronic lung disease of prematurity as well as several forms of acute and chronic adult lung disease. While TGFbeta1 appears to be the predominant isoform involved, elevated levels of all three isoforms have been demonstrated. The increase in TGFbeta precedes abnormalities in lung function and detectable lung pathology, but correlates with the severity of the disease. TGFbeta plays a key role in mediating fibrotic tissue remodeling by increasing the production and decreasing the degradation of connective tissue via several mechanisms.
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Affiliation(s)
- Ulrike Bartram
- University Children's Hospital, Josef-Schnewider-Strasse 2, 97080 Wuerzburg, Germany.
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Tanaka H, Komai M, Nagao K, Ishizaki M, Kajiwara D, Takatsu K, Delespesse G, Nagai H. Role of interleukin-5 and eosinophils in allergen-induced airway remodeling in mice. Am J Respir Cell Mol Biol 2004; 31:62-8. [PMID: 14975941 DOI: 10.1165/rcmb.2003-0305oc] [Citation(s) in RCA: 143] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Asthma is a chronic inflammatory disease characterized by variable bronchial obstruction, hyperresponsiveness, and by tissue damage known as airway remodeling. In the present study we demonstrate that interleukin (IL)-5 plays an obligatory role in the airway remodeling observed in experimental asthma. BALB/c mice sensitized by intraperitoneal injections of ovalbumin and exposed daily to aerosol of ovalbumin for up to 3 wk, develop eosinophilic infiltration of the bronchi and subepithelial and peribronchial fibrosis. The lesions are associated with increased amounts of hydroxyproline in the lungs and elevated levels of eosinophils and transforming growth factor (TGF)-beta1 in the bronchoalveolar lavage fluid. After 1 wk of allergen challenge, TGF-beta is mainly produced by eosinophils accumulated in the peribronchial and perivascular lesions. At a later stage of the disease, the main source of TGF-beta is myofibroblasts, identified by alpha-smooth muscle actin mAb. We show that all these lesions, including fibrosis, are abolished in sensitized and allergen-exposed IL-5 receptor-null mice, whereas they are markedly accentuated in IL-5 transgenic animals. More importantly, treatment of wild-type mice with neutralizing anti-IL-5 antibody, administered before each allergen challenge, almost completely prevented subepithelial and peribronchial fibrosis. These findings demonstrated that eosinophils are involved in allergen-induced subepithelial and peribronchial fibrosis probably by producing a fibrogenic factor, TGF-beta1.
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Affiliation(s)
- Hiroyuki Tanaka
- Department of Pharmacology, Gifu Pharmaceutical University, Gifu, Japan
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Hardie WD, Le Cras TD, Jiang K, Tichelaar JW, Azhar M, Korfhagen TR. Conditional expression of transforming growth factor-alpha in adult mouse lung causes pulmonary fibrosis. Am J Physiol Lung Cell Mol Physiol 2003; 286:L741-9. [PMID: 14660483 DOI: 10.1152/ajplung.00208.2003] [Citation(s) in RCA: 92] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
To determine whether overexpression of transforming growth factor (TGF)-alpha in the adult lung causes remodeling independently of developmental influences, we generated conditional transgenic mice expressing TGF-alpha in the epithelium under control of the doxycycline (Dox)-regulatable Clara cell secretory protein promoter. Two transgenic lines were generated, and following 4 days of Dox-induction TGF-alpha levels in whole lung homogenate were increased 13- to 18-fold above nontransgenic levels. After TGF-alpha induction, transgenic mice developed progressive pulmonary fibrosis and body weight loss, with mice losing 15% of their weight after 6 wk of TGF-alpha induction. Fibrosis was detected within 4 days of TGF-alpha induction and developed initially in the perivascular, peribronchial, and pleural regions but later extended into the interstitium. Fibrotic regions were composed of increased collagen and cellular proliferation and were adjacent to airway and alveolar epithelial sites of TGF-alpha expression. Fibrosis progressed in the absence of inflammatory cell infiltrates as determined by histology, without changes in bronchiolar alveolar lavage total or differential cell counts and without changes in proinflammatory cytokines TNF-alpha or IL-6. Active TGF-beta in whole lung homogenate was not altered 1 and 4 days after TGF-alpha induction, and immunostaining was not increased in the peribronchial/perivascular areas at all time points. Chronic epithelial expression of TGF-alpha in adult mice caused progressive pulmonary fibrosis associated with increased collagen and extracellular matrix deposition and increased cellular proliferation. Induction of pulmonary fibrosis by TGF-alpha was independent of inflammation or early activation of TGF-beta.
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Affiliation(s)
- William D Hardie
- Div. of Pulmonary Medicine, Cincinnati Children's Hospital Medical Center, 3333 Burnet Ave., Cincinnati, OH 45229-3039, USA.
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O'Reilly MA, Watkins RH, Staversky RJ, Maniscalco WM. Induced p21Cip1 in premature baboons with CLD: implications for alveolar hypoplasia. Am J Physiol Lung Cell Mol Physiol 2003; 285:L964-71. [PMID: 12871858 DOI: 10.1152/ajplung.00171.2003] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Aberrant pulmonary epithelial and mesenchymal cell proliferation occurs when newborns are treated with oxygen and ventilation to mitigate chronic lung disease. Because the cyclin-dependent kinase inhibitor p21 inhibits proliferation of oxygen-exposed cells, its expression was investigated in premature baboons delivered at 125 days (67% of term) and treated with oxygen and ventilation pro re nata (PRN) for 2, 6, 14, and 21 days. Approximately 5% of all cells expressed p21 during normal lung development of which <1% of these cells were pro-surfactant protein (SP)-B-positive epithelial cells. The percentage of cells expressing p21 increased threefold in all PRN-treated animals, but different cell populations expressed it during disease progression. Between 2 and 6 days of treatment, p21 was detected in 30-40% of pro-SP-B cells. In contrast, only 12% of pro-SP-B cells expressed p21 by 14 and 21 days of treatment, by which time p21 was also detected in mesenchymal cells. Even though increased epithelial and mesenchymal cell proliferation occurs during disease progression, those cells expressing p21 did not also express the proliferative marker Ki67. Thus two populations of epithelial and mesenchymal cells can be identified that are either expressing Ki67 and proliferating or expressing p21 and not proliferating. These data suggest that p21 may play a role in disorganized proliferation and alveolar hypoplasia seen in newborn chronic lung disease.
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Affiliation(s)
- Michael A O'Reilly
- Dept. of Pediatrics, Box 850, Univ. of Rochester, 601 Elm-wood Ave., Rochester, NY 14642, USA.
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41
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Peti-Peterdi J, Komlosi P, Fuson AL, Guan Y, Schneider A, Qi Z, Redha R, Rosivall L, Breyer MD, Bell PD. Luminal NaCl delivery regulates basolateral PGE2 release from macula densa cells. J Clin Invest 2003. [DOI: 10.1172/jci200318018] [Citation(s) in RCA: 122] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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Peti-Peterdi J, Komlosi P, Fuson AL, Guan Y, Schneider A, Qi Z, Redha R, Rosivall L, Breyer MD, Bell PD. Luminal NaCl delivery regulates basolateral PGE2 release from macula densa cells. J Clin Invest 2003; 112:76-82. [PMID: 12840061 PMCID: PMC162292 DOI: 10.1172/jci18018] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Macula densa (MD) cells express COX-2 and COX-2-derived PGs appear to signal the release of renin from the renal juxtaglomerular apparatus, especially during volume depletion. However, the synthetic machinery and identity of the specific prostanoid released from intact MD cells remains uncertain. In the present studies, a novel biosensor tool was engineered to directly determine whether MD cells release PGE2 in response to low luminal NaCl concentration ([NaCl]L). HEK293 cells were transfected with the Ca2+-coupled E-prostanoid receptor EP1 (HEK/EP1) and loaded with fura-2. HEK/EP1 cells produced a significant elevation in intracellular [Ca2+] ([Ca2+]i) by 29.6 +/- 12.8 nM (n = 6) when positioned at the basolateral surface of isolated perfused MD cells and [NaCl]L was reduced from 150 mM to zero. HEK/EP1 [Ca2+]i responses were observed mainly in preparations from rabbits on a low-salt diet and were completely inhibited by either a selective COX-2 inhibitor or an EP1 antagonist, and also by 100 microM luminal furosemide. Also, 20-mM graduated reductions in [NaCl]L between 80 and 0 mM caused step-by-step increases in HEK/EP1 [Ca2+]i. Low-salt diet greatly increased the expression of both COX-2 and microsome-associated PGE synthase (mPGES) in the MD. These studies provide the first direct evidence that intact MD cells synthesize and release PGE2 during reduced luminal salt content and suggest that this response is important in the control of renin release and renal vascular resistance during salt deprivation.
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Affiliation(s)
- Janos Peti-Peterdi
- Department of Medicine, University of Alabama at Birmingham, Alabama, USA.
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43
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Warburton D, Bellusci S, Del Moral PM, Kaartinen V, Lee M, Tefft D, Shi W. Growth factor signaling in lung morphogenetic centers: automaticity, stereotypy and symmetry. Respir Res 2003; 4:5. [PMID: 12818006 PMCID: PMC185249 DOI: 10.1186/1465-9921-4-5] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2002] [Revised: 01/28/2003] [Accepted: 02/17/2003] [Indexed: 12/16/2022] Open
Abstract
Lung morphogenesis is stereotypic, both for lobation and for the first several generations of airways, implying mechanistic control by a well conserved, genetically hardwired developmental program. This program is not only directed by transcriptional factors and peptide growth factor signaling, but also co-opts and is modulated by physical forces. Peptide growth factors signal within repeating epithelial-mesenchymal temporospatial patterns that constitute morphogenetic centers, automatically directing millions of repetitive events during both stereotypic branching and nonstereotypic branching as well as alveolar surface expansion phases of lung development. Transduction of peptide growth factor signaling within these centers is finely regulated at multiple levels. These may include ligand expression, proteolytic activation of latent ligand, ligand bioavailability, ligand binding proteins and receptor affinity and presentation, receptor complex assembly and kinase activation, phosphorylation and activation of adapter and messenger protein complexes as well as downstream events and cross-talk both inside and outside the nucleus. Herein we review the critical Sonic Hedgehog, Fibroblast Growth Factor, Bone Morphogenetic Protein, Vascular Endothelial Growth Factor and Transforming Growth Factorbeta signaling pathways and propose how they may be functionally coordinated within compound, highly regulated morphogenetic gradients that drive first stereotypic and then non-stereotypic, automatically repetitive, symmetrical as well as asymmetrical branching events in the lung.
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Affiliation(s)
- David Warburton
- Developmental Biology Program, Childrens Hospital Los Angeles Research Institute and the Center for Craniofacial Molecular Biology, Keck School of Medicine and School of Dentistry, University of Southern California
| | - Saverio Bellusci
- Developmental Biology Program, Childrens Hospital Los Angeles Research Institute and the Center for Craniofacial Molecular Biology, Keck School of Medicine and School of Dentistry, University of Southern California
| | - Pierre-Marie Del Moral
- Developmental Biology Program, Childrens Hospital Los Angeles Research Institute and the Center for Craniofacial Molecular Biology, Keck School of Medicine and School of Dentistry, University of Southern California
| | - Vesa Kaartinen
- Developmental Biology Program, Childrens Hospital Los Angeles Research Institute and the Center for Craniofacial Molecular Biology, Keck School of Medicine and School of Dentistry, University of Southern California
| | - Matt Lee
- Developmental Biology Program, Childrens Hospital Los Angeles Research Institute and the Center for Craniofacial Molecular Biology, Keck School of Medicine and School of Dentistry, University of Southern California
| | - Denise Tefft
- Developmental Biology Program, Childrens Hospital Los Angeles Research Institute and the Center for Craniofacial Molecular Biology, Keck School of Medicine and School of Dentistry, University of Southern California
| | - Wei Shi
- Developmental Biology Program, Childrens Hospital Los Angeles Research Institute and the Center for Craniofacial Molecular Biology, Keck School of Medicine and School of Dentistry, University of Southern California
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Abstract
The mechanisms that control proliferation and differentiation of embryonic lung mesenchyme are largely unknown. We describe an explant system in which exogenous recombinant N-Sonic Hedgehog (N-Shh) protein sustains the survival and proliferation of lung mesenchyme in a dose-dependent manner. In addition, Shh upregulates several mesenchymal cell markers, including its target gene Patched (Ptc), intercellular signaling genes Bone Morphogenetic Protein-4 (Bmp4) and Noggin (Nog), and smooth muscle actin and myosin. In explants exposed to N-Shh in the medium, these products are upregulated throughout the mesenchyme, but not in the periphery. This exclusion zone correlates with the presence of an overlying mesothelial layer, which, as in vivo, expresses Fibroblast Growth Factor 9 (Fgf9). Recombinant Fgf9 protein inhibits the differentiation response of the mesenchyme to N-Shh, but does not affect proliferation. We propose a model for how factors made by two epithelial cell populations, the inner endoderm and the outer jacket of mesothelium, coordinately regulate the proliferation and differentiation of the lung mesoderm.
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Affiliation(s)
- Molly Weaver
- Department of Cell and Developmental Biology, Vanderbilt University Medical Center, Nashville, TN 37232-2175, USA
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45
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Richman JM, Lee SH. About face: signals and genes controlling jaw patterning and identity in vertebrates. Bioessays 2003; 25:554-68. [PMID: 12766945 DOI: 10.1002/bies.10288] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The embryonic vertebrate face is composed of similarly sized buds of neural crest-derived mesenchyme encased in epithelium. These buds or facial prominences grow and fuse together to give the postnatal morphology characteristic of each species. Here we review the role of neural crest cells and foregut endoderm in differentiating facial features. We relate the developing facial prominences to the skeletal structure of the face and review the signals and genes that have been shown to play an important role in facial morphogenesis. We also examine two experiments one at the genetic level and one at the signal level in which transformation of facial prominences and subsequent change of jaw identity was induced. We propose that signals such as retinoids and BMPs and downstream transcription factors such as Distal-less related genes specify jaw identity.
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Affiliation(s)
- Joy M Richman
- Department of Oral Health Sciences, University of British Columbia, 2199 Wesbrook Mall, Vancouver, BC, V6T 1Z3 Canada.
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Tschumperlin DJ, Shively JD, Kikuchi T, Drazen JM. Mechanical stress triggers selective release of fibrotic mediators from bronchial epithelium. Am J Respir Cell Mol Biol 2003; 28:142-9. [PMID: 12540481 DOI: 10.1165/rcmb.2002-0121oc] [Citation(s) in RCA: 113] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Transforming growth factor-beta (TGF-beta) and endothelin (ET) are found in elevated amounts in the airways of individuals with asthma. The cellular source of these peptides and their role in mediating the airway fibrosis of chronic asthma are unknown. In response to mechanical stresses similar to those occurring in vivo during airway constriction, bronchial epithelial cells increase the steady-state level of mRNA for both ET-1 and ET-2, followed by increased release of ET protein. Mechanical stress also enhances release of TGF-beta2 from a preformed cell-associated pool. TGF-beta2 and ET act individually and, more importantly, synergistically to promote fibrotic protein synthesis in reporter fibroblasts. To confirm the role of these intermediates in stress-induced fibrosis, conditioned medium from mechanically stressed bronchial epithelial cells was shown to elicit fibrotic protein synthesis in reporter fibroblasts; this effect was significantly inhibited by combined treatment with ET receptor antagonists and a neutralizing antibody to TGF-beta2. These data are consistent with a primary pathogenic role for mechanical stress-induced release of both TGF-beta2 and ET in the subepithelial fibrosis that characterizes chronic asthma.
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Affiliation(s)
- Daniel J Tschumperlin
- Pulmonary and Critical Care Division, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
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47
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Poschet J, Perkett E, Deretic V. Hyperacidification in cystic fibrosis: links with lung disease and new prospects for treatment. Trends Mol Med 2002; 8:512-9. [PMID: 12421684 DOI: 10.1016/s1471-4914(02)02414-0] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
A new link between the genetic defect and lung pathology in cystic fibrosis (CF) has been established by the recent discovery of an abnormally acidic pH in the organelles of CF respiratory epithelial cells, along with an increased acidity of the CF airway surface liquid. The defect in cystic fibrosis transmembrane resistance regulator (CFTR) results in hyperacidification of the trans-Golgi network, an organelle responsible for glycosylation, and protein- and membrane-sorting in mammalian cells. Hyperacidification and altered surface glycoconjugates might contribute to mucus thickening, bacterial adhesion and colonization, inflammation, and irreversible tissue damage. The increased acidity of the intracellular organelles and of the lung lining in CF could be linked, and both represent potential therapeutic targets.
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Affiliation(s)
- Jens Poschet
- Dept of Molecular Genetics and Microbiology, University of New Mexico School of Medicine, Albuquerque, NM 87131, USA
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Gründer A, Ebel TT, Mallo M, Schwarzkopf G, Shimizu T, Sippel AE, Schrewe H. Nuclear factor I-B (Nfib) deficient mice have severe lung hypoplasia. Mech Dev 2002; 112:69-77. [PMID: 11850179 DOI: 10.1016/s0925-4773(01)00640-2] [Citation(s) in RCA: 84] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Binding sites for transcription factor nuclear factor one (NFI) proteins, encoded by four genes in the mouse, have been characterized from many tissue-specific genes. NFI genes are expressed in unique but overlapping patterns in embryonic and in adult tissues. Nfib is highly expressed in the embryonic lung. Here we show that Nfib null mutants die early postnatally and display severe lung hypoplasia. Heterozygotes do survive, but exhibit delayed pulmonary differentiation. Expression of transforming growth factor beta 1 (TGF-beta1) and sonic hedgehog (Shh) is not down-regulated in mutant lung epithelium at late stages of morphogenesis, which may result in incomplete lung maturation. Our study demonstrates that Nfib is essential for normal lung development, and suggests that it could be involved in the pathogenesis of respiratory distress syndromes in humans.
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Affiliation(s)
- Albert Gründer
- Institut fur Biologie III, Albert-Ludwigs-Universitat, Freiburg, Germany
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Bragg AD, Moses HL, Serra R. Signaling to the epithelium is not sufficient to mediate all of the effects of transforming growth factor beta and bone morphogenetic protein 4 on murine embryonic lung development. Mech Dev 2001; 109:13-26. [PMID: 11677049 DOI: 10.1016/s0925-4773(01)00508-1] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Many studies have suggested that transforming growth factor beta (TGF-beta) and bone morphogenetic protein 4 (Bmp4) regulate early development of the lung. In this study, administration of growth factors directly into the lumen of lungs grown in organ culture was used to limit their activity to the epithelium and test the hypothesis that signaling to the epithelium is sufficient to mediate the known effects of TGF-beta and BMP-4 on early lung development. Addition of TGF-beta1, beta2, or beta3 to the medium surrounding lungs grown in organ culture resulted in decreased branching, reduced cell proliferation, accumulation of alpha-smooth muscle actin protein (alpha-SMA) in the mesenchyme, and decreased expression of a marker for respiratory epithelium, surfactant protein-C (Sp-C). When TGF-beta1 was restricted to the epithelium, accumulation of alpha-SMA and inhibition of Sp-C expression were not observed but branching and proliferation were inhibited. In contrast, branching was not inhibited in lungs where TGF-beta2 or TGF-beta3 were restricted to the epithelium suggesting differences in the mechanism of signaling by TGF-beta1, TGF-beta2 or TGF -beta3 in lung. Addition of Bmp4 to the medium surrounding lungs grown in organ culture stimulated cell proliferation and branching morphogenesis; however, direct injection of Bmp4 into the lung lumen had no effect on proliferation or branching. Based on these data and data from mesenchyme-free cultures, we propose that the mesenchyme influences growth factor signaling in the lung.
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Affiliation(s)
- A D Bragg
- Vanderbilt Ingram Cancer Center, Vanderbilt University, Nashville, TN 37232, USA
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Laitakari J, Stenbäck F. Collagen matrix in development and progression of experimentally induced respiratory neoplasms in the hamster. Toxicol Pathol 2001; 29:514-27. [PMID: 11695568 DOI: 10.1080/019262301317226311] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Intratracheal instillations of 7H-dibenzo(c, g)carbazole (DBC), a tobacco smoke component, into Syrian golden hamsters, resulted in preneoplastic lesions and benign and malignant respiratory neoplasms. Neoplastic progression was associated with specific changes in the extracellular matrix (ECM), dependent on the stage of tumor development. DBC-induced tracheobronchial squamous metaplasia was associated with an increase in collagen type I and type III deposition in the subepithelial ECM, as observed by computer-assisted image analysis of immunohistochemical staining for the aminoterminal propeptides of collagen type I (PINP) and collagen type III (PIIINP). Increased collagen matrix synthesis was detected in dysplasia by in situ hybridization of alpha1(I) mRNA for collagen I and alpha1(III) mRNA for collagen type III after continued exposure to DBC. In well-differentiated squamous cell carcinomas with an expansive growth pattern, collagen deposition increased, as did fiber size. In moderately differentiated neoplasms, basement membrane (BM) destruction and invasion was associated with a destructive growth pattern and decreases in collagen synthesis and the deposition of new collagen. Preserved deposition of mature collagen was detected by staining for the telopeptide of collagen type I propeptide. In less differentiated tumors, ECM development was minimal, with few and small fibers, possibly explaining the rapid development of these neoplasms. Transforming growth factor beta (TGFbeta1) immunoreactivity was increased in hyperplastic epithelium and well differentiated neoplasms and decreased in dysplasia and less differentiated squamous cell carcinomas, while TGFbeta2 and TGFbeta3 expression was also distinct in neoplastic cells. Collagen synthesis and epithelial differentiation were associated with an increased number of myofibroblasts in the ECM and with increased TGFbeta3 immunoreactivity in differentiated cells and in the matrix. The nature of the composition of the ECM was related to neoplastic growth and progression when analyzed by computer-associated image analysis, revealing alterations in collagen structure, size, and shape.
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Affiliation(s)
- J Laitakari
- Department of Pathology, University of Oulu, Finland
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