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Kolousek A, Pak-Harvey E, Liu-Lam O, White M, Smith P, Henning F, Koval M, Levy JM. The Effects of Endogenous Cannabinoids on the Mammalian Respiratory System: A Scoping Review of Cyclooxygenase-Dependent Pathways. Cannabis Cannabinoid Res 2023; 8:434-444. [PMID: 37074668 PMCID: PMC10249741 DOI: 10.1089/can.2022.0277] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/20/2023] Open
Abstract
Introduction: The endogenous cannabinoid (endocannabinoid) system is an emerging target for the treatment of chronic inflammatory disease with the potential to advance treatment for many respiratory illnesses. The varied effects of endocannabinoids across tissue types makes it imperative that we explore their physiologic impact within unique tissue targets. The aim of this scoping review is to explore the impact of endocannabinoid activity on eicosanoid production as a measure of human airway inflammation. Methods: A scoping literature review was conducted according to PRISMA-ScR (Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews) guidelines. Search strategies using MeSH terms related to cannabinoids, eicosanoids, cyclooxygenase (COX), and the respiratory system were used to query Medline, Embase, Cochrane, CINAHL, Web of Science, and Biosis Previews in December 2021. Only studies that investigated the relationship between endocannabinoids and the eicosanoid system in mammalian respiratory tissue after 1992 were included. Results: Sixteen studies were incorporated in the final qualitative review. Endocannabinoid activation increases COX-2 expression, potentially through ceramide-dependent or p38 and p42/44 Mitogen-Activated Protein Kinase pathways and is associated with a concentration-dependent increase in prostaglandin (PG)E2. Inhibitors of endocannabinoid hydrolysis found either an increase or no change in levels of PGE2 and PGD2 and decreased levels of leukotriene (LT)B4, PGI2, and thromboxane A2 (TXA2). Endocannabinoids increase bronchial epithelial cell permeability and have vasorelaxant effects in human pulmonary arteries and cause contraction of bronchi and decreased gas trapping in guinea pigs. Inhibitors of endocannabinoid hydrolysis were found to have anti-inflammatory effects on pulmonary tissue and are primarily mediated by COX-2 and activation of eicosanoid receptors. Direct agonism of endocannabinoid receptors appears to play a minor role. Conclusion: The endocannabinoid system has diverse effects on the mammalian airway. While endocannabinoid-derived PGs can have anti-inflammatory effects, endocannabinoids also produce proinflammatory conditions, such as increased epithelial permeability and bronchial contraction. These conflicting findings suggest that endocannabinoids produce a variety of effects depending on their local metabolism and receptor agonism. Elucidation of the complex interplay between the endocannabinoid and eicosanoid pathways is key to leveraging the endocannabinoid system as a potential therapeutic target for human airway disease.
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Affiliation(s)
| | | | - Oliver Liu-Lam
- Emory University School of Medicine, Atlanta, Georgia, USA
| | - Mia White
- Emory Libraries, Emory University, Atlanta, Georgia, USA
| | - Prestina Smith
- Division of Pulmonary, Allergy, Critical Care, and Sleep Medicine, Department of Medicine, Emory University School of Medicine, Atlanta, Georgia, USA
| | | | - Michael Koval
- Division of Pulmonary, Allergy, Critical Care, and Sleep Medicine, Department of Medicine, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Joshua M. Levy
- Department of Otolaryngology—Head & Neck Surgery, Emory University School of Medicine, Atlanta, Georgia, USA
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Ta HQ, Teman NR, Kron IL, Roeser ME, Laubach VE. Steen solution protects pulmonary microvascular endothelial cells and preserves endothelial barrier after lipopolysaccharide-induced injury. J Thorac Cardiovasc Surg 2023; 165:e5-e20. [PMID: 35577593 PMCID: PMC9576825 DOI: 10.1016/j.jtcvs.2022.04.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 03/04/2022] [Accepted: 04/01/2022] [Indexed: 12/16/2022]
Abstract
OBJECTIVES Acute respiratory distress syndrome represents the devastating result of acute lung injury, with high mortality. Limited methods are available for rehabilitation of lungs affected by acute respiratory distress syndrome. Our laboratory has demonstrated rehabilitation of sepsis-injured lungs via normothermic ex vivo and in vivo perfusion with Steen solution (Steen). However, mechanisms responsible for the protective effects of Steen remain unclear. This study tests the hypothesis that Steen directly attenuates pulmonary endothelial barrier dysfunction and inflammation induced by lipopolysaccharide. METHODS Primary pulmonary microvascular endothelial cells were exposed to lipopolysaccharide for 4 hours and then recovered for 8 hours in complete media (Media), Steen, or Steen followed by complete media (Steen/Media). Oxidative stress, chemokines, permeability, interendothelial junction proteins, and toll-like receptor 4-mediated pathways were assessed in pulmonary microvascular endothelial cells using standard methods. RESULTS Lipopolysaccharide treatment of pulmonary microvascular endothelial cells and recovery in Media significantly induced reactive oxygen species, lipid peroxidation, expression of chemokines (eg, chemokine [C-X-C motif] ligand 1 and C-C motif chemokine ligand 2) and cell adhesion molecules (P-selectin, E-selectin, and vascular cell adhesion molecule 1), permeability, neutrophil transmigration, p38 mitogen-activated protein kinase and nuclear factor kappa B signaling, and decreased expression of tight and adherens junction proteins (zonula occludens-1, zonula occludens-2, and vascular endothelial-cadherin). All of these inflammatory pathways were significantly attenuated after recovery of pulmonary microvascular endothelial cells in Steen or Steen/Media. CONCLUSIONS Steen solution preserves pulmonary endothelial barrier function after lipopolysaccharide exposure by promoting an anti-inflammatory environment via attenuation of oxidative stress, toll-like receptor 4-mediated signaling, and conservation of interendothelial junctions. These protective mechanisms offer insight into the advancement of methods for in vivo lung perfusion with Steen for the treatment of severe acute respiratory distress syndrome.
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Affiliation(s)
| | | | | | | | - Victor E. Laubach
- Address for reprints: Victor E. Laubach, PhD, Department of Surgery, University of Virginia School of Medicine, PO Box 801359, Charlottesville, VA 22908
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Yadav R, Kumar Y, Dahiya D, Bhatia A. Claudins: The Newly Emerging Targets in Breast Cancer. Clin Breast Cancer 2022; 22:737-752. [PMID: 36175290 DOI: 10.1016/j.clbc.2022.09.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2022] [Accepted: 09/04/2022] [Indexed: 01/25/2023]
Abstract
Claudin-low breast cancers are recently described entities showing low expression of certain claudins and cell adhesion molecules. Claudins constitute the backbone of tight junctions (TJs) formed between 2 cells. Their dysregulation plays a vital role in tumorigenesis. First part of the article focuses on the role of claudins in the TJ organization, their structural-functional characteristics, and post-transcriptional and translational modifications. The latter part of the review attempts to summarize existing knowledge regarding the status of claudins in breast cancer. The article also provides an overview of the effect of claudins on tumor progression, metastasis, stemness, chemotherapy resistance, and their crosstalk with relevant signaling pathways in breast cancer. Claudins can act as 2-edged swords in tumors. Some claudins have either tumor-suppressive/ promoting action, while others work as both in a context-dependent manner. Claudins regulate many important events in breast cancer. However, the intricacies involved in their activity are poorly understood. Post-translational modifications in claudins and their impact on TJ integrity, function, and tumor behavior are still unclear. Although their role in adverse events in breast cancer is recognized, their potential to serve as relevant targets for future therapeutics, especially for difficult-to-treat subtypes of the above malignancy, remains to be explored.
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Affiliation(s)
- Reena Yadav
- Department of Experimental Medicine and Biotechnology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Yashwant Kumar
- Department of Immunopathology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Divya Dahiya
- Department of General Surgery, Postgraduate Institute of Medical Education and Research, Chandigarh, India
| | - Alka Bhatia
- Department of Experimental Medicine and Biotechnology, Postgraduate Institute of Medical Education and Research, Chandigarh, India.
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Airway Epithelial Cell Junctions as Targets for Pathogens and Antimicrobial Therapy. Pharmaceutics 2022; 14:pharmaceutics14122619. [PMID: 36559113 PMCID: PMC9786141 DOI: 10.3390/pharmaceutics14122619] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Revised: 11/22/2022] [Accepted: 11/24/2022] [Indexed: 11/29/2022] Open
Abstract
Intercellular contacts between epithelial cells are established and maintained by the apical junctional complexes (AJCs). AJCs conserve cell polarity and build epithelial barriers to pathogens, inhaled allergens, and environmental particles in the respiratory tract. AJCs consist of tight junctions (TJs) and adherens junctions (AJs), which play a key role in maintaining the integrity of the airway barrier. Emerging evidence has shown that different microorganisms cause airway barrier dysfunction by targeting TJ and AJ proteins. This review discusses the pathophysiologic mechanisms by which several microorganisms (bacteria and viruses) lead to the disruption of AJCs in airway epithelial cells. We present recent progress in understanding signaling pathways involved in the formation and regulation of cell junctions. We also summarize the potential chemical inhibitors and pharmacological approaches to restore the integrity of the airway epithelial barrier. Understanding the AJCs-pathogen interactions and mechanisms by which microorganisms target the AJC and impair barrier function may further help design therapeutic innovations to treat these infections.
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Berselli A, Benfenati F, Maragliano L, Alberini G. Multiscale modelling of claudin-based assemblies: a magnifying glass for novel structures of biological interfaces. Comput Struct Biotechnol J 2022; 20:5984-6010. [DOI: 10.1016/j.csbj.2022.10.038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Revised: 10/24/2022] [Accepted: 10/24/2022] [Indexed: 11/03/2022] Open
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Grund SC, Wu XX, Müller D, Wennemuth G, Grümmer R. Impact of endometrial claudin-3 deletion on murine implantation, decidualization and embryo development. Biol Reprod 2022; 107:984-997. [PMID: 35863769 DOI: 10.1093/biolre/ioac143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Revised: 05/10/2022] [Accepted: 07/07/2022] [Indexed: 11/12/2022] Open
Abstract
The composition of cell contacts in the endometrium plays an important role in the process of embryo implantation and the establishment of pregnancy. In previous studies, we showed an induction of the tight junction protein claudin-3 in the developing decidua from 6.5 dpc onwards. To evaluate the role if this specific claudin-3 distribution, we here evaluated the effect of an endometrial claudin-3 deletion in implantation and embryo development in claudin-3 knockout mice. Claudin-3 KO mice were fertile but revealed a slightly reduced amount of implantation sites as well as of litter size. Though implantation sites showed morphologically regularly developed embryos and deciduas, depth of ectoplacental cone invasion was reduced in tendency compared to controls. The weight of the implantation sites on 6.5 and 8.5 dpc as well as the weight of the embryos on 17.5 dpc, but not of the placentas, was significantly reduced in claudin-3 KO mice due to a maternal effect. This could be due to an impairment of decidualization as substantiated by a downregulation of the transcription of various decidua-associated genes in the early implantation sites of claudin-3 KO mice. The fact that claudin-3 KO mice are nevertheless fertile possibly may be compensated by the presence of other claudins like claudin-4 and claudin-10.
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Affiliation(s)
- Susanne C Grund
- Department of Anatomy, University Hospital, University of Duisburg-Essen, 45147 Essen, Germany
| | - Xin Xin Wu
- Department of Anatomy, University Hospital, University of Duisburg-Essen, 45147 Essen, Germany
| | - Dominik Müller
- Department of Pediatric Gastroenterology, Nephrology and Metabolic Diseases Charité Universitätsmedizin Berlin, 13353 Berlin, Germany
| | - Gunther Wennemuth
- Department of Anatomy, University Hospital, University of Duisburg-Essen, 45147 Essen, Germany
| | - Ruth Grümmer
- Department of Anatomy, University Hospital, University of Duisburg-Essen, 45147 Essen, Germany
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Single-cell transcriptomic analysis of neuroepithelial cells and other cell types of the gills of zebrafish (Danio rerio) exposed to hypoxia. Sci Rep 2022; 12:10144. [PMID: 35710785 PMCID: PMC9203529 DOI: 10.1038/s41598-022-13693-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Accepted: 05/26/2022] [Indexed: 12/21/2022] Open
Abstract
The fish gill is a multifunctional organ involved in numerous physiological processes, such as gas exchange and sensing of hypoxia by respiratory chemoreceptors, called neuroepithelial cells (NECs). Many studies have focused on zebrafish (Danio rerio) to investigate the structure, function and development of the gills, yet the transcriptomic profile of most gill cells remains obscure. We present the results of a comprehensive transcriptomic analysis of the gills of zebrafish using single-cell RNA sequencing (scRNA‐seq). Gill cells from ETvmat2:EGFP zebrafish were individually labelled before scRNA‐seq library construction using 10× Genomics Chromium technology. 12,819 cells were sequenced with an average depth of over 27,000 reads per cell. We identified a median of 485 genes per cell and 16 cell clusters, including NECs, neurons, pavement cells, endothelial cells and mitochondrion-rich cells. The identity of NECs was confirmed by expression of slc18a2, encoding the vesicular monoamine transporter, Vmat2. Highly differentially-expressed genes in NECs included tph1a, encoding tryptophan hydroxylase, sv2 (synaptic vesicle protein), and proteins implicated in O2 sensing (ndufa4l2a, cox8al and epas1a). In addition, NECs and neurons expressed genes encoding transmembrane receptors for serotonergic, cholinergic or dopaminergic neurotransmission. Differential expression analysis showed a clear shift in the transcriptome of NECs following 14 days of acclimation to hypoxia. NECs in the hypoxia group showed high expression of genes involved in cell cycle control and proliferation. The present article provides a complete cell atlas for the zebrafish gill and serves as a platform for future studies investigating the molecular biology and physiology of this organ.
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Keulers L, Dehghani A, Knippels L, Garssen J, Papadopoulos N, Folkerts G, Braber S, van Bergenhenegouwen J. Probiotics, prebiotics, and synbiotics to prevent or combat air pollution consequences: The gut-lung axis. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2022; 302:119066. [PMID: 35240267 DOI: 10.1016/j.envpol.2022.119066] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 02/24/2022] [Accepted: 02/25/2022] [Indexed: 05/26/2023]
Abstract
Air pollution exposure is a public health emergency, which attributes globally to an estimated seven million deaths on a yearly basis We are all exposed to air pollutants, varying from ambient air pollution hanging over cities to dust inside the home. It is a mixture of airborne particulate matter and gases that can be subdivided into three categories based on particle diameter. The smallest category called PM0.1 is the most abundant. A fraction of the particles included in this category might enter the blood stream spreading to other parts of the body. As air pollutants can enter the body via the lungs and gut, growing evidence links its exposure to gastrointestinal and respiratory impairments and diseases, like asthma, rhinitis, respiratory tract infections, Crohn's disease, ulcerative colitis, and abdominal pain. It has become evident that there exists a crosstalk between the respiratory and gastrointestinal tracts, commonly referred to as the gut-lung axis. Via microbial secretions, metabolites, immune mediators and lipid profiles, these two separate organ systems can influence each other. Well-known immunomodulators and gut health stimulators are probiotics, prebiotics, together called synbiotics. They might combat air pollution-induced systemic inflammation and oxidative stress by optimizing the microbiota composition and microbial metabolites, thereby stimulating anti-inflammatory pathways and strengthening mucosal and epithelial barriers. Although clinical studies investigating the role of probiotics, prebiotics, and synbiotics in an air pollution setting are lacking, these interventions show promising health promoting effects by affecting the gastrointestinal- and respiratory tract. This review summarizes the current data on how air pollution can affect the gut-lung axis and might impact gut and lung health. It will further elaborate on the potential role of probiotics, prebiotics and synbiotics on the gut-lung axis, and gut and lung health.
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Affiliation(s)
- Loret Keulers
- Division of Pharmacology, Utrecht Institute for Pharmaceutical Sciences, Faculty of Science, Utrecht University, Universiteitsweg 99, 3584, CG, Utrecht, the Netherlands; Danone Nutricia Research, Uppsalalaan 12, 3584, CT, Utrecht, the Netherlands.
| | - Ali Dehghani
- Division of Pharmacology, Utrecht Institute for Pharmaceutical Sciences, Faculty of Science, Utrecht University, Universiteitsweg 99, 3584, CG, Utrecht, the Netherlands
| | - Leon Knippels
- Division of Pharmacology, Utrecht Institute for Pharmaceutical Sciences, Faculty of Science, Utrecht University, Universiteitsweg 99, 3584, CG, Utrecht, the Netherlands; Danone Nutricia Research, Uppsalalaan 12, 3584, CT, Utrecht, the Netherlands
| | - Johan Garssen
- Division of Pharmacology, Utrecht Institute for Pharmaceutical Sciences, Faculty of Science, Utrecht University, Universiteitsweg 99, 3584, CG, Utrecht, the Netherlands; Danone Nutricia Research, Uppsalalaan 12, 3584, CT, Utrecht, the Netherlands
| | - Nikolaos Papadopoulos
- Centre for Paediatrics and Child Health, Institute of Human Development, University of Manchester, Oxford Road M13 9PL, Manchester, United Kingdom
| | - Gert Folkerts
- Division of Pharmacology, Utrecht Institute for Pharmaceutical Sciences, Faculty of Science, Utrecht University, Universiteitsweg 99, 3584, CG, Utrecht, the Netherlands
| | - Saskia Braber
- Division of Pharmacology, Utrecht Institute for Pharmaceutical Sciences, Faculty of Science, Utrecht University, Universiteitsweg 99, 3584, CG, Utrecht, the Netherlands
| | - Jeroen van Bergenhenegouwen
- Division of Pharmacology, Utrecht Institute for Pharmaceutical Sciences, Faculty of Science, Utrecht University, Universiteitsweg 99, 3584, CG, Utrecht, the Netherlands; Danone Nutricia Research, Uppsalalaan 12, 3584, CT, Utrecht, the Netherlands
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Looi K, Larcombe AN, Perks KL, Berry LJ, Zosky GR, Rigby P, Knight DA, Kicic A, Stick SM. Previous Influenza Infection Exacerbates Allergen Specific Response and Impairs Airway Barrier Integrity in Pre-Sensitized Mice. Int J Mol Sci 2021; 22:ijms22168790. [PMID: 34445491 PMCID: PMC8395745 DOI: 10.3390/ijms22168790] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2021] [Revised: 08/04/2021] [Accepted: 08/11/2021] [Indexed: 01/15/2023] Open
Abstract
In this study we assessed the effects of antigen exposure in mice pre-sensitized with allergen following viral infection on changes in lung function, cellular responses and tight junction expression. Female BALB/c mice were sensitized to ovalbumin and infected with influenza A before receiving a second ovalbumin sensitization and challenge with saline, ovalbumin (OVA) or house dust mite (HDM). Fifteen days post-infection, bronchoalveolar inflammation, serum antibodies, responsiveness to methacholine and barrier integrity were assessed. There was no effect of infection alone on bronchoalveolar lavage cellular inflammation 15 days post-infection; however, OVA or HDM challenge resulted in increased bronchoalveolar inflammation dominated by eosinophils/neutrophils or neutrophils, respectively. Previously infected mice had higher serum OVA-specific IgE compared with uninfected mice. Mice previously infected, sensitized and challenged with OVA were most responsive to methacholine with respect to airway resistance, while HDM challenge caused significant increases in both tissue damping and tissue elastance regardless of previous infection status. Previous influenza infection was associated with decreased claudin-1 expression in all groups and decreased occludin expression in OVA or HDM-challenged mice. This study demonstrates the importance of the respiratory epithelium in pre-sensitized individuals, where influenza-infection-induced barrier disruption resulted in increased systemic OVA sensitization and downstream effects on lung function.
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Affiliation(s)
- Kevin Looi
- Wal-yan Respiratory Research Centre, Telethon Kids Institute, Nedlands 6009, Australia; (K.L.); (K.L.P.); (L.J.B.); (A.K.); (S.M.S.)
- Occupation, Environment and Safety, School of Population Health, Curtin University, Perth 6845, Australia
| | - Alexander N. Larcombe
- Wal-yan Respiratory Research Centre, Telethon Kids Institute, Nedlands 6009, Australia; (K.L.); (K.L.P.); (L.J.B.); (A.K.); (S.M.S.)
- Occupation, Environment and Safety, School of Population Health, Curtin University, Perth 6845, Australia
- Correspondence:
| | - Kara L. Perks
- Wal-yan Respiratory Research Centre, Telethon Kids Institute, Nedlands 6009, Australia; (K.L.); (K.L.P.); (L.J.B.); (A.K.); (S.M.S.)
| | - Luke J. Berry
- Wal-yan Respiratory Research Centre, Telethon Kids Institute, Nedlands 6009, Australia; (K.L.); (K.L.P.); (L.J.B.); (A.K.); (S.M.S.)
| | - Graeme R. Zosky
- Menzies Institute for Medical Research, College of Health and Medicine, University of Tasmania, Hobart 7001, Australia;
- Tasmanian School of Medicine, College of Health and Medicine, University of Tasmania, Hobart 7001, Australia
| | - Paul Rigby
- Centre for Microscopy, Characterisation and Analysis (CMCA), University of Western Australia, Nedlands 6009, Australia;
| | - Darryl A. Knight
- School of Biomedical Sciences and Pharmacy, University of Newcastle, Callaghan 2308, Australia;
- Priority Research Centre for Asthma and Respiratory Disease, Hunter Medical Research Institute, Newcastle 2305, Australia
- Department of Anaesthesiology, Pharmacology and Therapeutics, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Anthony Kicic
- Wal-yan Respiratory Research Centre, Telethon Kids Institute, Nedlands 6009, Australia; (K.L.); (K.L.P.); (L.J.B.); (A.K.); (S.M.S.)
- Occupation, Environment and Safety, School of Population Health, Curtin University, Perth 6845, Australia
- Centre for Cell Therapy and Regenerative Medicine, University of Western Australia, Nedlands 6009, Australia
- Department of Respiratory and Sleep Medicine, Perth Children’s Hospital, Perth 6009, Australia
| | - Stephen M. Stick
- Wal-yan Respiratory Research Centre, Telethon Kids Institute, Nedlands 6009, Australia; (K.L.); (K.L.P.); (L.J.B.); (A.K.); (S.M.S.)
- Centre for Cell Therapy and Regenerative Medicine, University of Western Australia, Nedlands 6009, Australia
- Department of Respiratory and Sleep Medicine, Perth Children’s Hospital, Perth 6009, Australia
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Smyth T, Georas SN. Effects of ozone and particulate matter on airway epithelial barrier structure and function: a review of in vitro and in vivo studies. Inhal Toxicol 2021; 33:177-192. [PMID: 34346824 DOI: 10.1080/08958378.2021.1956021] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
The airway epithelium represents a crucial line of defense against the spread of inhaled pathogens. As the epithelium is the first part of the body to be exposed to the inhaled environment, it must act as both a barrier to and sentinel against any inhaled agents. Despite its vital role in limiting the spread of inhaled pathogens, the airway epithelium is also regularly exposed to air pollutants which disrupt its normal function. Here we review the current understanding of the structure and composition of the airway epithelial barrier, as well as the impact of inhaled pollutants, including the reactive gas ozone and particulate matter, on epithelial function. We discuss the current in vitro, rodent model, and human exposure findings surrounding the impact of various inhaled pollutants on epithelial barrier function, mucus production, and mucociliary clearance. Detailed information on how inhaled pollutants impact epithelial structure and function will further our understanding of the adverse health effects of air pollution exposure.
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Affiliation(s)
- Timothy Smyth
- Department of Environmental Medicine, University of Rochester Medical Center, Rochester, NY, USA
| | - Steve N Georas
- Department of Environmental Medicine, University of Rochester Medical Center, Rochester, NY, USA.,Department of Medicine, University of Rochester Medical Center, Rochester, NY, USA
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Zhang Y, Zhang L, Chen W, Zhang Y, Wang X, Dong Y, Zhang W, Lin X. Shp2 regulates PM2.5-induced airway epithelial barrier dysfunction by modulating ERK1/2 signaling pathway. Toxicol Lett 2021; 350:62-70. [PMID: 34252507 DOI: 10.1016/j.toxlet.2021.07.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Revised: 07/01/2021] [Accepted: 07/07/2021] [Indexed: 11/27/2022]
Abstract
The impact of fine particulate matter (PM2.5) on public health has received increasing attention. Through various biochemical mechanisms, PM2.5 alters the normal structure and function of the airway epithelium, causing epithelial barrier dysfunction. Src homology domain 2-containing protein tyrosine phosphatase 2 (Shp2) has been implicated in various respiratory diseases; however, its role in PM2.5-induced epithelial barrier dysfunction remains unclear. Herein, we assessed the regulatory effects of Shp2 on PM2.5-mediated epithelial barrier function and tight junction (TJ) protein expression in both mice and human pulmonary epithelial (16HBE) cells. We observed that Shp2 levels were upregulated and claudin-4 levels were downregulated after PM2.5 stimulation in vivo and in vitro. Mice were exposed to PM2.5 to induce acute lung injury, and disrupted epithelial barrier function, with decreased transepithelial electrical resistance (TER) and increased paracellular flux that was observed in 16HBE cells. In contrast, the selective inhibition or knockdown of Shp2 retained airway epithelial barrier function and reversed claudin-4 downregulation that triggered by PM2.5, and these effects may occur through the ERK1/2 MAPK signaling pathway. These data highlight an important role of Shp2 in PM2.5-induced airway epithelial barrier dysfunction and suggest a possible new course of therapy for PM2.5-induced respiratory diseases.
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Affiliation(s)
- Youting Zhang
- Department of Pharmacy, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, China
| | - Likang Zhang
- Wenzhou Medical University, Wenzhou, Zhejiang, 325035, China
| | - Wanwan Chen
- Department of Pathology, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, China
| | - Yuanyuan Zhang
- Department of Pediatric Allergy and Immunology, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, China
| | - Xiaoming Wang
- Department of Pediatric Allergy and Immunology, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, China
| | - Yaoyao Dong
- Department of Pharmacy, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, China
| | - Weixi Zhang
- Department of Pediatric Allergy and Immunology, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, China.
| | - Xixi Lin
- Department of Pharmacy, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, China.
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Kim YH, Kim KJ, D’Argenio DZ, Crandall ED. Characteristics of Passive Solute Transport across Primary Rat Alveolar Epithelial Cell Monolayers. MEMBRANES 2021; 11:331. [PMID: 33946241 PMCID: PMC8145727 DOI: 10.3390/membranes11050331] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 04/26/2021] [Accepted: 04/27/2021] [Indexed: 11/16/2022]
Abstract
Primary rat alveolar epithelial cell monolayers (RAECM) were grown without (type I cell-like phenotype, RAECM-I) or with (type II cell-like phenotype, RAECM-II) keratinocyte growth factor to assess passive transport of 11 hydrophilic solutes. We estimated apparent permeability (Papp) in the absence/presence of calcium chelator EGTA to determine the effects of perturbing tight junctions on "equivalent" pores. Papp across RAECM-I and -II in the absence of EGTA are similar and decrease as solute size increases. We modeled Papp of the hydrophilic solutes across RAECM-I/-II as taking place via heterogeneous populations of equivalent pores comprised of small (0.41/0.32 nm radius) and large (9.88/11.56 nm radius) pores, respectively. Total equivalent pore area is dominated by small equivalent pores (99.92-99.97%). The number of small and large equivalent pores in RAECM-I was 8.55 and 1.29 times greater, respectively, than those in RAECM-II. With EGTA, the large pore radius in RAECM-I/-II increased by 1.58/4.34 times and the small equivalent pore radius increased by 1.84/1.90 times, respectively. These results indicate that passive diffusion of hydrophilic solutes across an alveolar epithelium occurs via small and large equivalent pores, reflecting interactions of transmembrane proteins expressed in intercellular tight junctions of alveolar epithelial cells.
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Affiliation(s)
- Yong Ho Kim
- Will Rogers Institute Pulmonary Research Center and Hastings Center for Pulmonary Research, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033-0906, USA; (Y.H.K.); (K.-J.K.)
- Division of Pulmonary, Critical Care and Sleep Medicine, Department of Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033-0906, USA
| | - Kwang-Jin Kim
- Will Rogers Institute Pulmonary Research Center and Hastings Center for Pulmonary Research, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033-0906, USA; (Y.H.K.); (K.-J.K.)
- Division of Pulmonary, Critical Care and Sleep Medicine, Department of Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033-0906, USA
- Department of Biomedical Engineering, Viterbi School of Engineering, University of Southern California, Los Angeles, CA 90089-1111, USA;
- Department of Physiology and Neuroscience, Keck School of Medicine, University of Southern California, Los Angeles, CA 90089-9037, USA
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA 90089-9121, USA
| | - David Z. D’Argenio
- Department of Biomedical Engineering, Viterbi School of Engineering, University of Southern California, Los Angeles, CA 90089-1111, USA;
| | - Edward D. Crandall
- Will Rogers Institute Pulmonary Research Center and Hastings Center for Pulmonary Research, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033-0906, USA; (Y.H.K.); (K.-J.K.)
- Division of Pulmonary, Critical Care and Sleep Medicine, Department of Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033-0906, USA
- Department of Pathology, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033-9092, USA
- Mork Family Department of Chemical Engineering and Materials Science, Viterbi School of Engineering, University of Southern California, Los Angeles, CA 90089-1211, USA
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13
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Huang ZQ, Liu J, Ong HH, Yuan T, Zhou XM, Wang J, Tan KS, Chow VT, Yang QT, Shi L, Ye J, Wang DY. Interleukin-13 Alters Tight Junction Proteins Expression Thereby Compromising Barrier Function and Dampens Rhinovirus Induced Immune Responses in Nasal Epithelium. Front Cell Dev Biol 2020; 8:572749. [PMID: 33102478 PMCID: PMC7546404 DOI: 10.3389/fcell.2020.572749] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Accepted: 09/07/2020] [Indexed: 12/15/2022] Open
Abstract
Tight junctions (TJs) are intercellular structures which are essential for epithelial barrier function and play an important role in antimicrobial defense. Epithelium dysfunction and type-2-skewed inflammation are two main pathological phenomena of chronic rhinosinusitis with nasal polyps (CRSwNP). However, the effect of pro-inflammatory type-2 cytokine IL-13 on TJs in CRSwNP is poorly understood. Nasal biopsies of CRSwNP patients and in vitro IL-13-matured human nasal epithelial cells (hNECs) were used to analyze epithelial markers and TJ proteins. Epithelium permeability, transepithelial electrical resistance (TEER), expression of TJs were quantified for IL-13-matured hNECs and that with RV infection. The expression of occludin, claudin-3, and ZO-1 were significantly decreased in CRSwNP biopsies and in hNECs after IL-13 treatment. IL-13 treatment increased epithelium permeability, decreased TEER and altered hNECs composition resulting in lesser ciliated cells and mucus over-secretion. Interestingly, claudin-3 is selectively expressed on ciliated cells. While RV infection induced minimal changes to TJs, the IL-13-matured hNECs has reduced capacity for upregulation of IFN-λ1 and CXCL10 but further increased the expression of TSLP upon RV infection. These findings suggested that IL-13-mediated dysfunction of TJs and compromised epithelial barrier. IL-13-induced cilia loss conferred lowered viral replication and impaired antiviral responses of nasal epithelium against RV infection.
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Affiliation(s)
- Zhi-Qun Huang
- Department of Otolaryngology-Head and Neck Surgery, First Affiliated Hospital of Nanchang University, Jiangxi, China.,Department of Otolaryngology, Yong Loo Lin School of Medicine, National University of Singapore, National University Health System, Singapore, Singapore.,Department of Otolaryngology-Head and Neck Surgery, Affiliated Hospital of Jiujiang University, Jiangxi, China
| | - Jing Liu
- Department of Otolaryngology, Yong Loo Lin School of Medicine, National University of Singapore, National University Health System, Singapore, Singapore
| | - Hsiao Hui Ong
- Department of Otolaryngology, Yong Loo Lin School of Medicine, National University of Singapore, National University Health System, Singapore, Singapore
| | - Tian Yuan
- Department of Otolaryngology, Yong Loo Lin School of Medicine, National University of Singapore, National University Health System, Singapore, Singapore.,Department of Otorhinolaryngology-Head and Neck Surgery, Third Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Xiang-Min Zhou
- Department of Otolaryngology, Yong Loo Lin School of Medicine, National University of Singapore, National University Health System, Singapore, Singapore.,Department of Otolaryngology, Second Hospital of Shandong University, Jinan, China
| | - Jun Wang
- Department of Otolaryngology-Head and Neck Surgery, First Affiliated Hospital of Nanchang University, Jiangxi, China
| | - Kai Sen Tan
- Department of Otolaryngology, Yong Loo Lin School of Medicine, National University of Singapore, National University Health System, Singapore, Singapore
| | - Vincent T Chow
- NUHS Infectious Diseases Translational Research Program, Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Qin-Tai Yang
- Department of Otorhinolaryngology-Head and Neck Surgery, Third Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Li Shi
- Department of Otolaryngology, Second Hospital of Shandong University, Jinan, China
| | - Jing Ye
- Department of Otolaryngology-Head and Neck Surgery, First Affiliated Hospital of Nanchang University, Jiangxi, China
| | - De-Yun Wang
- Department of Otolaryngology, Yong Loo Lin School of Medicine, National University of Singapore, National University Health System, Singapore, Singapore
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14
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Young BM, Shankar K, Tho CK, Pellegrino AR, Heise RL. Laminin-driven Epac/Rap1 regulation of epithelial barriers on decellularized matrix. Acta Biomater 2019; 100:223-234. [PMID: 31593773 DOI: 10.1016/j.actbio.2019.10.009] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Revised: 10/03/2019] [Accepted: 10/03/2019] [Indexed: 12/28/2022]
Abstract
Decellularized tissues offer a unique tool for developing regenerative biomaterials or in vitro platforms for the study of cell-extracellular matrix (ECM) interactions. One main challenge associated with decellularized lung tissue is that ECM components can be stripped away or altered by the detergents used to remove cellular debris. Without characterizing the composition of lung decellularized ECM (dECM) and the cellular response caused by the altered composition, it is difficult to utilize dECM for regeneration and specifically, engineering the complexities of the alveolar-capillary barrier. This study takes steps towards uncovering if dECM must be enhanced with lost ECM proteins to achieve proper epithelial barrier formation. To achieve this, the epithelial barrier function was assessed on dECM coatings with and without the systematic addition of several key basement membrane proteins. After comparing barrier function on collagen I, fibronectin, laminin, and dECM in varying combinations as an in vitro coating, the alveolar epithelium exhibited superior barrier function when dECM was supplemented with laminin as evidenced by trans-epithelial electrical resistance (TEER) and permeability assays. Increased barrier resistance with laminin addition was associated with upregulation of Claudin-18, E-cadherin, and junction adhesion molecule (JAM)-A, and stabilization of zonula occludens (ZO)-1 at junction complexes. The Epac/Rap1 pathway was observed to play a role in the ECM-mediated barrier function determined by protein expression and Epac inhibition. These findings revealed potential ECM coatings and molecular therapeutic targets for improved regeneration with decellularized scaffolds. STATEMENT OF SIGNIFICANCE: Efforts to produce a transplantable organ-scale biomaterial for lung regeneration has not been entirely successful to date, due to incomplete cell-cell junction formation, ultimately leading to severe edema in vivo. To fully understand the process of alveolar junction formation on ECM-derived biomaterials, this research has characterized and tailored decellularized ECM (dECM) to mitigate reductions in barrier strength or cell attachment caused by abnormal ECM compositions or detergent damage to dECM. These results indicate that laminin-driven Epac signaling plays a vital role in the stabilization of the alveolar barrier. Addition of laminin or Epac agonists during alveolar regeneration can reduce epithelial permeability within bioengineered lungs.
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Affiliation(s)
- Bethany M Young
- Department of Biomedical Engineering, Virginia Commonwealth University, 800 E. Leigh St, Room 1071, Richmond, VA 23219, United States
| | - Keerthana Shankar
- Department of Biomedical Engineering, Virginia Commonwealth University, 800 E. Leigh St, Room 1071, Richmond, VA 23219, United States
| | - Cindy K Tho
- Department of Biomedical Engineering, Virginia Commonwealth University, 800 E. Leigh St, Room 1071, Richmond, VA 23219, United States
| | - Amanda R Pellegrino
- Department of Biomedical Engineering and Nursing, Duquesne University, 600 Forbes Ave, Pittsburg, Pennsylvania 15282, United States
| | - Rebecca L Heise
- Department of Biomedical Engineering, Virginia Commonwealth University, 800 E. Leigh St, Room 1071, Richmond, VA 23219, United States; Department of Physiology and Biophysics, Virginia Commonwealth University School of Medicine, 1101 East Marshall St, Richmond, Virginia 23298, United States.
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15
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Li X, Liu H, Yu W, Liu X, Liu C. Tandem mass tag (TMT) proteomic analysis of fetal lungs revealed differential expression of tight junction proteins in a rat model of congenital diaphragmatic hernia. Biomed Pharmacother 2019; 121:109621. [PMID: 31734580 DOI: 10.1016/j.biopha.2019.109621] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Revised: 11/01/2019] [Accepted: 11/01/2019] [Indexed: 02/04/2023] Open
Abstract
OBJECTIVE Congenital diaphragmatic hernia (CDH) is a common and often lethal birth defect characterized by congenital lung malformation, which severely affects neonate prognosis and mortality. This study aimed to investigate differences in protein expression in order to elucidate the mechanism of CDH-associated pulmonary hypoplasia during the early stage of lung development using tandem mass tag (TMT) quantitative proteomics. METHODS Nitrofen was administered orally to establish a rat CDH model, and pathological changes were evaluated through hematoxylin-eosin (H&E), PCNA, and Ki67 staining at the pseudoglandular stage. Fetal lungs were then collected, pooled before TMT labeling, and subjected to mass spectrometry. Immunohistochemistry (IHC), Western blotting, and Q-PCR were used to further validate the candidate proteins. RESULTS A total of 79 differentially expressed proteins (DEPs) were identified when CDH and control lungs were compared, and further bioinformatics analysis showed that these proteins play important roles in tight-junctions, phospholipase D signaling, and the HIF-1 signaling pathway. Three differentially expressed proteins, Cldn3, Magi1, and Myh9 are involved in the tight-junction pathway (P < 0.05), and their differential expressions were confirmed by IHC, Western blotting, and Q-PCR. CONCLUSION These findings indicate that alterations of tight-junction protein expression may play an important role in the pathogenesis of abnormal lung development in CDH. Further studies are warranted to verify the mechanism by which these tight-junction proteins influence the pathogenesis of CDH-associated pulmonary hypoplasia.
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Affiliation(s)
- Xue Li
- Department of Gynecology and Obstetrics, Shengjing Hospital of China Medical University, Shenyang, China; Key Laboratory of Maternal-Fetal Medicine of Liaoning Province, Benxi, China.
| | - Hao Liu
- Department of Gynecology and Obstetrics, Shengjing Hospital of China Medical University, Shenyang, China; Key Laboratory of Maternal-Fetal Medicine of Liaoning Province, Benxi, China.
| | - Wenqian Yu
- Department of Gynecology and Obstetrics, Shengjing Hospital of China Medical University, Shenyang, China; Key Laboratory of Maternal-Fetal Medicine of Liaoning Province, Benxi, China.
| | - Xiaomei Liu
- Department of Gynecology and Obstetrics, Shengjing Hospital of China Medical University, Shenyang, China; Key Laboratory of Maternal-Fetal Medicine of Liaoning Province, Benxi, China.
| | - Caixia Liu
- Department of Gynecology and Obstetrics, Shengjing Hospital of China Medical University, Shenyang, China; Key Laboratory of Maternal-Fetal Medicine of Liaoning Province, Benxi, China.
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16
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A Breath of Fresh Air in the Fog of Antimicrobial Resistance: Inhaled Polymyxins for Gram-Negative Pneumonia. Antibiotics (Basel) 2019; 8:antibiotics8010027. [PMID: 30884839 PMCID: PMC6466860 DOI: 10.3390/antibiotics8010027] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Revised: 03/08/2019] [Accepted: 03/12/2019] [Indexed: 01/08/2023] Open
Abstract
Despite advancements in therapy, pneumonia remains the leading cause of death due to infectious diseases. Novel treatment strategies are desperately needed to optimize the antimicrobial therapy of patients suffering from this disease. One such strategy that has recently garnered significant attention is the use of inhaled antibiotics to rapidly achieve therapeutic concentrations directly at the site of infection. In particular, there is significant interest in the role of inhaled polymyxins for the treatment of nosocomial pneumonia, including ventilator-associated pneumonia, due to their retained activity against multi-drug resistant Gram-negative pathogens, including Acinetobacter baumannii and Pseudomonas aeruginosa. This review will provide a comprehensive overview of the pharmacokinetic/pharmacodynamic profile, clinical outcomes, safety, and potential role of inhaled polymyxins in clinical practice.
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17
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Increase in resistance to anticancer drugs involves occludin in spheroid culture model of lung adenocarcinoma A549 cells. Sci Rep 2018; 8:15157. [PMID: 30310131 PMCID: PMC6181945 DOI: 10.1038/s41598-018-33566-w] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Accepted: 10/01/2018] [Indexed: 12/12/2022] Open
Abstract
Chemoresistance is a serious issue in the therapy of many cancers, but the molecular mechanism is little understood. The mRNA level of occludin (OCLN), a tight junctional protein, was increased in the cisplatin (CDDP), doxorubicin (DXR), 7-ethyl-10-hydroxy-camptothecin, or gemcitabine-resistant human lung adenocarcinoma A549 cells. Here, we investigated the regulatory mechanism and pathophysiological role of OCLN. OCLN was mainly localized at tight junctions in A549 and CDDP-resistant A549 (A549/CDDP) cells. The level of p-Akt in A549/CDDP cells was higher than that in A549 cells, and the mRNA and protein levels of OCLN were suppressed by a phosphoinositide 3-kinase (PI3K)/Akt pathway inhibitor, LY-294002, suggesting that a PI3K/Akt pathway is involved in the elevation of OCLN expression. The overexpression of OCLN in A549 cells decreased paracellular permeability to DXR. Cytotoxicity to CDDP was unaffected by OCLN-overexpression in 2D culture model. In 3D culture model, the spheroid size, hypoxic level, and cell viability were significantly elevated by CDDP resistance, but not by OCLN-overexpression. The accumulation inside the spheroids and toxicity of DXR were correlated with OCLN expression. Our data suggest that OCLN is not directly involved in the chemoresistance, but it enhances chemoresistance mediated by suppression of accumulation of anticancer drugs inside the spheroids.
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18
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Vyas-Read S, Vance RJ, Wang W, Colvocoresses-Dodds J, Brown LA, Koval M. Hyperoxia induces paracellular leak and alters claudin expression by neonatal alveolar epithelial cells. Pediatr Pulmonol 2018; 53:17-27. [PMID: 29168340 PMCID: PMC5938176 DOI: 10.1002/ppul.23681] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2016] [Revised: 01/03/2017] [Accepted: 01/25/2017] [Indexed: 12/16/2022]
Abstract
BACKGROUND Premature neonates frequently require oxygen supplementation as a therapeutic intervention that, while necessary, also exposes the lung to significant oxidant stress. We hypothesized that hyperoxia has a deleterious effect on alveolar epithelial barrier function rendering the neonatal lung susceptible to injury and/or bronchopulmonary dysplasia (BPD). MATERIALS AND METHODS We examined the effects of exposure to 85% oxygen on neonatal rat alveolar barrier function in vitro and in vivo. Whole lung was measured using wet-to-dry weight ratios and bronchoalveolar lavage protein content and cultured primary neonatal alveolar epithelial cells (AECs) were measured using transepithelial electrical resistance (TEER) and paracellular flux measurements. Expression of claudin-family tight junction proteins, E-cadherin and the Snail transcription factor SNAI1 were measured by Q-PCR, immunoblot and confocal immunofluorescence microscopy. RESULTS Cultured neonatal AECs exposed to 85% oxygen showed impaired barrier function. This oxygen-induced increase in paracellular leak was associated with altered claudin expression, where claudin-3 and -18 were downregulated at both the mRNA and protein level. Claudin-4 and -5 mRNA were also decreased, although protein expression of these claudins was largely maintained. Lung alveolarization and barrier function in vivo were impaired in response to hyperoxia. Oxygen exposure also significantly decreased E-cadherin expression and induced expression of the SNAI1 transcription factor in vivo and in vitro. CONCLUSIONS These data support a model in which hyperoxia has a direct impact on alveolar tight and adherens junctions to impair barrier function. Strategies to antagonize the effects of high oxygen on alveolar junctions may potentially reverse this deleterious effect.
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Affiliation(s)
- Shilpa Vyas-Read
- Division of Neonatology, Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia.,Emory + Children's Center for Cystic Fibrosis and Airways Disease Research, Emory University School of Medicine and Children's Healthcare of Atlanta, Atlanta, Georgia
| | - Rachel J Vance
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Medicine, Emory University School of Medicine, Atlanta, Georgia
| | - Wenyi Wang
- Division of Neonatology, Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia
| | | | - Lou Ann Brown
- Division of Neonatology, Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia.,Emory + Children's Center for Cystic Fibrosis and Airways Disease Research, Emory University School of Medicine and Children's Healthcare of Atlanta, Atlanta, Georgia
| | - Michael Koval
- Emory + Children's Center for Cystic Fibrosis and Airways Disease Research, Emory University School of Medicine and Children's Healthcare of Atlanta, Atlanta, Georgia.,Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Medicine, Emory University School of Medicine, Atlanta, Georgia.,Department of Cell Biology, Emory University School of Medicine, Atlanta, Georgia
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19
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Cai J, Culley MK, Zhao Y, Zhao J. The role of ubiquitination and deubiquitination in the regulation of cell junctions. Protein Cell 2017; 9:754-769. [PMID: 29080116 PMCID: PMC6107491 DOI: 10.1007/s13238-017-0486-3] [Citation(s) in RCA: 64] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2017] [Accepted: 10/09/2017] [Indexed: 12/11/2022] Open
Abstract
Maintenance of cell junctions plays a crucial role in the regulation of cellular functions including cell proliferation, permeability, and cell death. Disruption of cell junctions is implicated in a variety of human disorders, such as inflammatory diseases and cancers. Understanding molecular regulation of cell junctions is important for development of therapeutic strategies for intervention of human diseases. Ubiquitination is an important type of post-translational modification that primarily regulates endogenous protein stability, receptor internalization, enzyme activity, and protein-protein interactions. Ubiquitination is tightly regulated by ubiquitin E3 ligases and can be reversed by deubiquitinating enzymes. Recent studies have been focusing on investigating the effect of protein stability in the regulation of cell-cell junctions. Ubiquitination and degradation of cadherins, claudins, and their interacting proteins are implicated in epithelial and endothelial barrier disruption. Recent studies have revealed that ubiquitination is involved in regulation of Rho GTPases’ biological activities. Taken together these studies, ubiquitination plays a critical role in modulating cell junctions and motility. In this review, we will discuss the effects of ubiquitination and deubiquitination on protein stability and expression of key proteins in the cell-cell junctions, including junction proteins, their interacting proteins, and small Rho GTPases. We provide an overview of protein stability in modulation of epithelial and endothelial barrier integrity and introduce potential future search directions to better understand the effects of ubiquitination on human disorders caused by dysfunction of cell junctions.
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Affiliation(s)
- Junting Cai
- Acute Lung Injury Center of Excellence, Division of Pulmonary, Asthma, and Critical Care Medicine, Department of Medicine, The University of Pittsburgh, Pittsburgh, PA, 15213, USA.,Xiangya Hospital of Central South University, Changsha, 410008, China
| | - Miranda K Culley
- Acute Lung Injury Center of Excellence, Division of Pulmonary, Asthma, and Critical Care Medicine, Department of Medicine, The University of Pittsburgh, Pittsburgh, PA, 15213, USA
| | - Yutong Zhao
- Acute Lung Injury Center of Excellence, Division of Pulmonary, Asthma, and Critical Care Medicine, Department of Medicine, The University of Pittsburgh, Pittsburgh, PA, 15213, USA
| | - Jing Zhao
- Acute Lung Injury Center of Excellence, Division of Pulmonary, Asthma, and Critical Care Medicine, Department of Medicine, The University of Pittsburgh, Pittsburgh, PA, 15213, USA.
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20
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Wittekindt OH. Tight junctions in pulmonary epithelia during lung inflammation. Pflugers Arch 2017; 469:135-147. [PMID: 27921210 PMCID: PMC5203840 DOI: 10.1007/s00424-016-1917-3] [Citation(s) in RCA: 136] [Impact Index Per Article: 19.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Revised: 11/23/2016] [Accepted: 11/27/2016] [Indexed: 12/31/2022]
Abstract
Inflammatory lung diseases like asthma bronchiale, chronic obstructive pulmonary disease and allergic airway inflammation are widespread public diseases that constitute an enormous burden to the health systems. Mainly classified as inflammatory diseases, the treatment focuses on strategies interfering with local inflammatory responses by the immune system. Inflammatory lung diseases predispose patients to severe lung failures like alveolar oedema, respiratory distress syndrome and acute lung injury. These life-threatening syndromes are caused by increased permeability of the alveolar and airway epithelium and exudate formation. However, the mechanism underlying epithelium barrier breakdown in the lung during inflammation is elusive. This review emphasises the role of the tight junction of the airway epithelium as the predominating structure conferring epithelial tightness and preventing exudate formation and the impact of inflammatory perturbations on their function.
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Affiliation(s)
- Oliver H Wittekindt
- Institute of General Physiology, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany.
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21
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Barmeyer C, Fromm M, Schulzke JD. Active and passive involvement of claudins in the pathophysiology of intestinal inflammatory diseases. Pflugers Arch 2016; 469:15-26. [PMID: 27904960 DOI: 10.1007/s00424-016-1914-6] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2016] [Revised: 11/20/2016] [Accepted: 11/22/2016] [Indexed: 12/18/2022]
Abstract
Intestinal inflammatory diseases, four of which are discussed here, are associated with alterations of claudins. In ulcerative colitis, diarrhea and antigen entry into the mucosa occurs. Claudin-2 is upregulated but data on other claudins are still limited or vary (e.g., claudin-1 and -4). Apart from that, tight junction changes contribute to diarrhea via a leak flux mechanism, while protection against antigen entry disappears behind epithelial gross lesions (erosions) and apoptotic foci. Crohn's disease is additionally characterized by a claudin-5 and claudin-8 reduction which plays an active role in antigen uptake already before gross lesions appear. In microscopic colitis (MC), upregulation of claudin-2 expression is weak and a reduction in claudin-4 may be only passively involved, while sodium malabsorption represents the main diarrheal mechanism. However, claudin-5 is removed from MC tight junctions which may be an active trigger for inflammation through antigen uptake along the so-called leaky gut concept. In celiac disease, primary barrier defects are discussed in the context of candidate genes as PARD3 which regulate cell polarity and tight junctions. The loss of claudin-5 allows small antigens to invade, while the reductions in others like claudin-3 are rather passive events. Taken together, the specific role of single tight junction proteins for the onset and perpetuation of inflammation and the recovery from these diseases is far from being fully understood and is clearly dependent on the stage of the disease, the background of the other tight junction components, the transport activity of the mucosa, and the presence of other barrier features like gross lesions, an orchestral interplay which is discussed in this article.
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Affiliation(s)
- Christian Barmeyer
- Institute of Clinical Physiology, Charité-Universitätsmedizin Berlin, 12203, Berlin, Germany
| | - Michael Fromm
- Institute of Clinical Physiology, Charité-Universitätsmedizin Berlin, 12203, Berlin, Germany
| | - Jörg-Dieter Schulzke
- Institute of Clinical Physiology, Charité-Universitätsmedizin Berlin, 12203, Berlin, Germany.
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22
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Schlingmann B, Overgaard CE, Molina SA, Lynn KS, Mitchell LA, Dorsainvil White S, Mattheyses AL, Guidot DM, Capaldo CT, Koval M. Regulation of claudin/zonula occludens-1 complexes by hetero-claudin interactions. Nat Commun 2016; 7:12276. [PMID: 27452368 PMCID: PMC4962485 DOI: 10.1038/ncomms12276] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2016] [Accepted: 06/15/2016] [Indexed: 01/06/2023] Open
Abstract
Claudins are tetraspan transmembrane tight-junction proteins that regulate epithelial barriers. In the distal airspaces of the lung, alveolar epithelial tight junctions are crucial to regulate airspace fluid. Chronic alcohol abuse weakens alveolar tight junctions, priming the lung for acute respiratory distress syndrome, a frequently lethal condition caused by airspace flooding. Here we demonstrate that in response to alcohol, increased claudin-5 paradoxically accompanies an increase in paracellular leak and rearrangement of alveolar tight junctions. Claudin-5 is necessary and sufficient to diminish alveolar epithelial barrier function by impairing the ability of claudin-18 to interact with a scaffold protein, zonula occludens 1 (ZO-1), demonstrating that one claudin affects the ability of another claudin to interact with the tight-junction scaffold. Critically, a claudin-5 peptide mimetic reverses the deleterious effects of alcohol on alveolar barrier function. Thus, claudin controlled claudin-scaffold protein interactions are a novel target to regulate tight-junction permeability.
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Affiliation(s)
- Barbara Schlingmann
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Medicine, Emory University, 205 Whitehead Building, 615 Michael Street, Atlanta, Georgia 30322, USA.,Emory Alcohol and Lung Biology Center, Emory University, Atlanta, Georgia 30322, USA
| | - Christian E Overgaard
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Medicine, Emory University, 205 Whitehead Building, 615 Michael Street, Atlanta, Georgia 30322, USA.,Emory Alcohol and Lung Biology Center, Emory University, Atlanta, Georgia 30322, USA
| | - Samuel A Molina
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Medicine, Emory University, 205 Whitehead Building, 615 Michael Street, Atlanta, Georgia 30322, USA.,Emory Alcohol and Lung Biology Center, Emory University, Atlanta, Georgia 30322, USA
| | - K Sabrina Lynn
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Medicine, Emory University, 205 Whitehead Building, 615 Michael Street, Atlanta, Georgia 30322, USA.,Emory Alcohol and Lung Biology Center, Emory University, Atlanta, Georgia 30322, USA
| | - Leslie A Mitchell
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Medicine, Emory University, 205 Whitehead Building, 615 Michael Street, Atlanta, Georgia 30322, USA
| | - StevenClaude Dorsainvil White
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Medicine, Emory University, 205 Whitehead Building, 615 Michael Street, Atlanta, Georgia 30322, USA.,Emory Alcohol and Lung Biology Center, Emory University, Atlanta, Georgia 30322, USA
| | - Alexa L Mattheyses
- Department of Cell Biology, Emory University, Atlanta, Georgia 30322, USA
| | - David M Guidot
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Medicine, Emory University, 205 Whitehead Building, 615 Michael Street, Atlanta, Georgia 30322, USA.,Emory Alcohol and Lung Biology Center, Emory University, Atlanta, Georgia 30322, USA.,Atlanta Veterans Affairs Medical Center, Decatur, Georgia 30033, USA
| | - Christopher T Capaldo
- Department of Pathology; Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Michael Koval
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Medicine, Emory University, 205 Whitehead Building, 615 Michael Street, Atlanta, Georgia 30322, USA.,Emory Alcohol and Lung Biology Center, Emory University, Atlanta, Georgia 30322, USA.,Department of Cell Biology, Emory University, Atlanta, Georgia 30322, USA
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23
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Wenzler E, Fraidenburg DR, Scardina T, Danziger LH. Inhaled Antibiotics for Gram-Negative Respiratory Infections. Clin Microbiol Rev 2016; 29:581-632. [PMID: 27226088 PMCID: PMC4978611 DOI: 10.1128/cmr.00101-15] [Citation(s) in RCA: 75] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Gram-negative organisms comprise a large portion of the pathogens responsible for lower respiratory tract infections, especially those that are nosocomially acquired, and the rate of antibiotic resistance among these organisms continues to rise. Systemically administered antibiotics used to treat these infections often have poor penetration into the lung parenchyma and narrow therapeutic windows between efficacy and toxicity. The use of inhaled antibiotics allows for maximization of target site concentrations and optimization of pharmacokinetic/pharmacodynamic indices while minimizing systemic exposure and toxicity. This review is a comprehensive discussion of formulation and drug delivery aspects, in vitro and microbiological considerations, pharmacokinetics, and clinical outcomes with inhaled antibiotics as they apply to disease states other than cystic fibrosis. In reviewing the literature surrounding the use of inhaled antibiotics, we also highlight the complexities related to this route of administration and the shortcomings in the available evidence. The lack of novel anti-Gram-negative antibiotics in the developmental pipeline will encourage the innovative use of our existing agents, and the inhaled route is one that deserves to be further studied and adopted in the clinical arena.
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Affiliation(s)
- Eric Wenzler
- University of Illinois at Chicago, College of Pharmacy, Chicago, Illinois, USA
| | - Dustin R Fraidenburg
- Department of Medicine, Division of Pulmonary, Critical Care, Sleep and Allergy Medicine, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Tonya Scardina
- Loyola University Medical Center, Chicago, Illinois, USA
| | - Larry H Danziger
- University of Illinois at Chicago, College of Pharmacy, Chicago, Illinois, USA University of Illinois at Chicago, College of Medicine, Chicago, Illinois, USA
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24
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Song MJ, Davidovich N, Lawrence GG, Margulies SS. Superoxide mediates tight junction complex dissociation in cyclically stretched lung slices. J Biomech 2016; 49:1330-1335. [PMID: 26592435 PMCID: PMC4864146 DOI: 10.1016/j.jbiomech.2015.10.032] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Revised: 10/20/2015] [Accepted: 10/21/2015] [Indexed: 12/25/2022]
Abstract
We found that stretching Type I rat alveolar epithelial cell (RAEC) monolayers at magnitudes that correspond to high tidal-volume mechanical ventilation results in the production of reactive oxygen species, including nitric oxide and superoxide. Scavenging superoxide with Tiron eliminated the stretch-induced increase in cell monolayer permeability, and similar results were reported for rats ventilated at large tidal volumes, suggesting that oxidative stress plays an important role in barrier impairment in ventilator-induced lung injury associated with large stretch and tidal volumes. In this communication we show that mechanisms that involve oxidative injury are also present in a novel precision cut lung slices (PCLS) model under identical mechanical loads. PCLSs from healthy rats were stretched cyclically to 37% change in surface area for 1 hour. Superoxide was visualized using MitoSOX. To evaluate functional relationships, in separate stretch studies superoxide was scavenged using Tiron or mito-Tempo. PCLS and RAEC permeability was assessed as tight junction (TJ) protein (occludin, claudin-4 and claudin-7) dissociation from zona occludins-1 (ZO-1) via co-immunoprecipitation and Western blot, after 1h (PCLS) or 10min (RAEC) of stretch. Superoxide was increased significantly in PCLS, and Tiron and mito-Tempo dramatically attenuated the response, preventing claudin-4 and claudin-7 dissociation from ZO-1. Using a novel PCLS model for ventilator-induced lung injury studies, we have shown that uniform, biaxial, cyclic stretch generates ROS in the slices, and that superoxide scavenging that can protect the lung tissue under stretch conditions. We conclude that PCLS offer a valuable platform for investigating antioxidant treatments to prevent ventilation-induced lung injury.
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Affiliation(s)
- Min Jae Song
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, USA
| | - Nurit Davidovich
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, USA
| | - Gladys G Lawrence
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, USA
| | - Susan S Margulies
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, USA.
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25
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Togami K, Chono S, Tada H. Alteration in Intrapulmonary Pharmacokinetics of Aerosolized Model Compounds Due to Disruption of the Alveolar Epithelial Barriers Following Bleomycin-Induced Pulmonary Fibrosis in Rats. J Pharm Sci 2016; 105:1327-34. [DOI: 10.1016/j.xphs.2015.12.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Revised: 12/06/2015] [Accepted: 12/09/2015] [Indexed: 12/17/2022]
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26
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Patkee WRA, Carr G, Baker EH, Baines DL, Garnett JP. Metformin prevents the effects of Pseudomonas aeruginosa on airway epithelial tight junctions and restricts hyperglycaemia-induced bacterial growth. J Cell Mol Med 2016; 20:758-64. [PMID: 26837005 PMCID: PMC4864950 DOI: 10.1111/jcmm.12784] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Accepted: 12/07/2015] [Indexed: 12/20/2022] Open
Abstract
Lung disease and elevation of blood glucose are associated with increased glucose concentration in the airway surface liquid (ASL). Raised ASL glucose is associated with increased susceptibility to infection by respiratory pathogens including Staphylococcus aureus and Pseudomonas aeruginosa. We have previously shown that the anti‐diabetes drug, metformin, reduces glucose‐induced S. aureus growth across in vitro airway epithelial cultures. The aim of this study was to investigate whether metformin has the potential to reduce glucose‐induced P. aeruginosa infections across airway epithelial (Calu‐3) cultures by limiting glucose permeability. We also explored the effect of P. aeruginosa and metformin on airway epithelial barrier function by investigating changes in tight junction protein abundance. Apical P. aeruginosa growth increased with basolateral glucose concentration, reduced transepithelial electrical resistance (TEER) and increased paracellular glucose flux. Metformin pre‐treatment of the epithelium inhibited the glucose‐induced growth of P. aeruginosa, increased TEER and decreased glucose flux. Similar effects on bacterial growth and TEER were observed with the AMP activated protein kinase agonist, 5‐aminoimidazole‐4‐carboxamide ribonucleotide. Interestingly, metformin was able to prevent the P. aeruginosa‐induced reduction in the abundance of tight junction proteins, claudin‐1 and occludin. Our study highlights the potential of metformin to reduce hyperglycaemia‐induced P. aeruginosa growth through airway epithelial tight junction modulation, and that claudin‐1 and occludin could be important targets to regulate glucose permeability across airway epithelia and supress bacterial growth. Further investigation into the mechanisms regulating metformin and P. aeruginosa action on airway epithelial tight junctions could yield new therapeutic targets to prevent/suppress hyperglycaemia‐induced respiratory infections, avoiding the use of antibiotics.
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Affiliation(s)
| | - Georgina Carr
- Institute of Cellular Medicine, Newcastle University, Newcastle-upon-Tyne, UK
| | - Emma H Baker
- Institute for Infection and Immunity, St George's, University of London, London, UK
| | - Deborah L Baines
- Institute for Infection and Immunity, St George's, University of London, London, UK
| | - James P Garnett
- Institute of Cellular Medicine, Newcastle University, Newcastle-upon-Tyne, UK
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27
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Capaldo CT, Nusrat A. Claudin switching: Physiological plasticity of the Tight Junction. Semin Cell Dev Biol 2015; 42:22-9. [PMID: 25957515 DOI: 10.1016/j.semcdb.2015.04.003] [Citation(s) in RCA: 69] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2015] [Revised: 04/15/2015] [Accepted: 04/16/2015] [Indexed: 01/22/2023]
Abstract
Tight Junctions (TJs) are multi-molecular complexes in epithelial tissues that regulate paracellular permeability. Within the TJ complex, claudins proteins span the paracellular space to form a seal between adjacent cells. This seal allows regulated passage of ions, fluids, and solutes, contingent upon the complement of claudins expressed. With as many as 27 claudins in the human genome, the TJ seal is complex indeed. This review focuses on changes in claudin expression within the epithelial cells of the gastrointestinal tract, where claudin differentiation results in several physiologically distinct TJs within the lifetime of the cell. We also review mechanistic studies revealing that TJs are highly dynamic, with the potential to undergo molecular remodeling while structurally intact. Therefore, physiologic Tight Junction plasticity involves both the adaptability of claudin expression and gene specific retention in the TJ; a process we term claudin switching.
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Affiliation(s)
- Christopher T Capaldo
- Epithelial Pathobiology and Mucosal Inflammation Research Unit, Department of Pathology and Laboratory Medicine, Emory University, Atlanta, GA 30322, United States
| | - Asma Nusrat
- Epithelial Pathobiology and Mucosal Inflammation Research Unit, Department of Pathology and Laboratory Medicine, Emory University, Atlanta, GA 30322, United States; Department of Pathology, University of Michigan, Ann Arbor, MI 48109, United States.
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28
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Schlingmann B, Molina SA, Koval M. Claudins: Gatekeepers of lung epithelial function. Semin Cell Dev Biol 2015; 42:47-57. [PMID: 25951797 DOI: 10.1016/j.semcdb.2015.04.009] [Citation(s) in RCA: 125] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Accepted: 04/24/2015] [Indexed: 12/25/2022]
Abstract
The lung must maintain a proper barrier between airspaces and fluid filled tissues in order to maintain lung fluid balance. Central to maintaining lung fluid balance are epithelial cells which create a barrier to water and solutes. The barrier function of these cells is mainly provided by tight junction proteins known as claudins. Epithelial barrier function varies depending on the different needs within the segments of the respiratory tree. In the lower airways, fluid is required to maintain mucociliary clearance, whereas in the terminal alveolar airspaces a thin layer of surfactant enriched fluid lowers surface tension to prevent airspace collapse and is critical for gas exchange. As the epithelial cells within the segments of the respiratory tree differ, the composition of claudins found in these epithelial cells is also different. Among these differences is claudin-18 which is uniquely expressed by the alveolar epithelial cells. Other claudins, notably claudin-4 and claudin-7, are more ubiquitously expressed throughout the respiratory epithelium. Claudin-5 is expressed by both pulmonary epithelial and endothelial cells. Based on in vitro and in vivo model systems and histologic analysis of lungs from human patients, roles for specific claudins in maintaining barrier function and protecting the lung from the effects of acute injury and disease are being identified. One surprising finding is that claudin-18 and claudin-4 control lung cell phenotype and inflammation beyond simply maintaining a selective paracellular permeability barrier. This suggests claudins have more nuanced roles for the control of airway and alveolar physiology in the healthy and diseased lung.
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Affiliation(s)
- Barbara Schlingmann
- Department of Medicine, Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Emory University School of Medicine, Atlanta, GA 30322, United States; Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322, United States
| | - Samuel A Molina
- Department of Medicine, Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Emory University School of Medicine, Atlanta, GA 30322, United States; Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322, United States
| | - Michael Koval
- Department of Medicine, Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Emory University School of Medicine, Atlanta, GA 30322, United States; Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322, United States.
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29
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Overgaard CE, Schlingmann B, Dorsainvil White S, Ward C, Fan X, Swarnakar S, Brown LAS, Guidot DM, Koval M. The relative balance of GM-CSF and TGF-β1 regulates lung epithelial barrier function. Am J Physiol Lung Cell Mol Physiol 2015; 308:L1212-23. [PMID: 25888574 DOI: 10.1152/ajplung.00042.2014] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2014] [Accepted: 04/09/2015] [Indexed: 11/22/2022] Open
Abstract
Lung barrier dysfunction is a cardinal feature of the acute respiratory distress syndrome (ARDS). Alcohol abuse, which increases the risk of ARDS two- to fourfold, induces transforming growth factor (TGF)-β1, which increases epithelial permeability and impairs granulocyte/macrophage colony-stimulating factor (GM-CSF)-dependent barrier integrity in experimental models. We hypothesized that the relative balance of GM-CSF and TGF-β1 signaling regulates lung epithelial barrier function. GM-CSF and TGF-β1 were tested separately and simultaneously for their effects on lung epithelial cell barrier function in vitro. TGF-β1 alone caused an ∼ 25% decrease in transepithelial resistance (TER), increased paracellular flux, and was associated with projections perpendicular to tight junctions ("spikes") containing claudin-18 that colocalized with F-actin. In contrast, GM-CSF treatment induced an ∼ 20% increase in TER, decreased paracellular flux, and showed decreased colocalization of spike-associated claudin-18 with F-actin. When simultaneously administered to lung epithelial cells, GM-CSF antagonized the effects of TGF-β1 on epithelial barrier function in cultured cells. Given this, GM-CSF and TGF-β1 levels were measured in bronchoalveolar lavage (BAL) fluid from patients with ventilator-associated pneumonia and correlated with markers for pulmonary edema and patient outcome. In patient BAL fluid, protein markers of lung barrier dysfunction, serum α2-macroglobulin, and IgM levels were increased at lower ratios of GM-CSF/TGF-β1. Critically, patients who survived had significantly higher GM-CSF/TGF-β1 ratios than nonsurviving patients. This study provides experimental and clinical evidence that the relative balance between GM-CSF and TGF-β1 signaling is a key regulator of lung epithelial barrier function. The GM-CSF/TGF-β1 ratio in BAL fluid may provide a concentration-independent biomarker that can predict patient outcomes in ARDS.
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Affiliation(s)
- Christian E Overgaard
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Medicine, Emory University, Atlanta, Georgia; Emory Alcohol and Lung Biology Center, Emory University, Atlanta, Georgia
| | - Barbara Schlingmann
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Medicine, Emory University, Atlanta, Georgia
| | - StevenClaude Dorsainvil White
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Medicine, Emory University, Atlanta, Georgia
| | - Christina Ward
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Medicine, Emory University, Atlanta, Georgia; Emory Alcohol and Lung Biology Center, Emory University, Atlanta, Georgia
| | - Xian Fan
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Medicine, Emory University, Atlanta, Georgia; Atlanta Veterans Affairs Medical Center, Decatur, Georgia
| | - Snehasikta Swarnakar
- Drug Development Diagnostics and Biotechnology, CSIR-Indian Institute of Chemical Biology, Kolkata, India
| | - Lou Ann S Brown
- Emory Alcohol and Lung Biology Center, Emory University, Atlanta, Georgia; Division of Neonatology, Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia
| | - David M Guidot
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Medicine, Emory University, Atlanta, Georgia; Emory Alcohol and Lung Biology Center, Emory University, Atlanta, Georgia; Atlanta Veterans Affairs Medical Center, Decatur, Georgia
| | - Michael Koval
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Medicine, Emory University, Atlanta, Georgia; Emory Alcohol and Lung Biology Center, Emory University, Atlanta, Georgia; Department of Cell Biology, Emory University, Atlanta, Georgia;
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30
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Transcriptional regulators of claudins in epithelial tight junctions. Mediators Inflamm 2015; 2015:219843. [PMID: 25948882 PMCID: PMC4407569 DOI: 10.1155/2015/219843] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2014] [Revised: 09/22/2014] [Accepted: 10/03/2014] [Indexed: 02/06/2023] Open
Abstract
Human gastrointestinal tract is covered by a monolayer of specialized epithelial cells that constitute a protective barrier surface to external toxic and infectious agents along with metabolic and digestive functions. Intercellular junctions, among epithelial cells, such as desmosomes, adherens, gap, and tight junctions (TJs), not only provide mechanical integrity but also limit movement of molecules across the monolayer. TJ is a complex structure composed of approximately 35 different proteins that interact with each other at the apical side of two adjacent epithelial cells. Claudin family proteins are important members of TJ with so far 24 known isoforms in different species. Claudins are structural proteins of TJ that help to control the paracellular movement by forming fence and barrier across the epithelial monolayer. Altered function of claudins is implicated in different form of cancers, inflammatory bowel diseases (IBDs), and leaky diarrhea. Based on their significant role in the molecular architecture of TJ, diversity, and disease association, further understanding about claudin family proteins and their genetic/epigenetic regulators is indispensable.
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31
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Ward C, Schlingmann B, Stecenko AA, Guidot DM, Koval M. NF-κB inhibitors impair lung epithelial tight junctions in the absence of inflammation. Tissue Barriers 2015; 3:e982424. [PMID: 25838984 DOI: 10.4161/21688370.2014.982424] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2014] [Accepted: 10/27/2014] [Indexed: 01/11/2023] Open
Abstract
NF-κB (p50/p65) is the best characterized transcription factor known to regulate cell responses to inflammation. However, NF-κB is also constitutively expressed. We used inhibitors of the classical NF-κB signaling pathway to determine whether this transcription factor has a role in regulating alveolar epithelial tight junctions. Primary rat type II alveolar epithelial cells were isolated and cultured on Transwell permeable supports coated with collagen for 5 d to generate a model type I cell monolayer. Treatment of alveolar epithelial monolayers overnight with one of 2 different IκB kinase inhibitors (BAY 11-7082 or BMS-345541) resulted in a dose-dependent decrease in TER at concentrations that did not affect cell viability. In response to BMS-345541 treatment there was an increase in total claudin-4 and claudin-5 along with a decrease in claudin-18, as determined by immunoblot. However, there was little effect on the total amount of cell-associated claudin-7, occludin, junctional adhesion molecule A (JAM-A), zonula occludens (ZO)-1 or ZO-2. Moreover, treatment with BMS-345541 resulted in altered tight junction morphology as assessed by immunofluorescence microscopy. Cells treated with BMS-345541 had an increase in claudin-18 containing projections emanating from tight junctions ("spikes") that were less prominent in control cells. There also were several areas of cell-cell contact which lacked ZO-1 and ZO-2 localization as well as rearrangements to the actin cytoskeleton in response to BMS-345541. Consistent with an anti-inflammatory effect, BMS-345541 antagonized the deleterious effects of lipopolysaccharide (LPS) on alveolar epithelial barrier function. However, BMS-345541 also inhibited the ability of GM-CSF to increase alveolar epithelial TER. These data suggest a dual role for NF-κB in regulating alveolar barrier function and that constitutive NF-κB function is required for the integrity of alveolar epithelial tight junctions.
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Key Words
- ARDS, Acute Respiratory Distress Syndrome
- GM-CSF, Granulocyte Macrophage Colony Stimulating Factor
- IL, interleukin
- IκB, Inhibitor of κB
- JAM-A, junctional adhesion molecule A
- LPS, lipolysaccharide
- NF-κB, nuclear factor kappa-light-chain-enhancer of activated B cells
- PBS, phosphate buffered saline
- TER, transepithelial resistance
- TNF, Tumor Necrosis Factor
- ZO, zonula occludens
- alveolus
- claudin
- lung barrier
- tight junction
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Affiliation(s)
- Christina Ward
- Pulmonary Division; Department of Medicine; Emory University School of Medicine ; Atlanta, GA USA
| | - Barbara Schlingmann
- Pulmonary Division; Department of Medicine; Emory University School of Medicine ; Atlanta, GA USA
| | - Arlene A Stecenko
- Department of Pediatrics; Emory University School of Medicine ; Atlanta, GA USA
| | - David M Guidot
- Pulmonary Division; Department of Medicine; Emory University School of Medicine ; Atlanta, GA USA
| | - Michael Koval
- Pulmonary Division; Department of Medicine; Emory University School of Medicine ; Atlanta, GA USA ; Department of Cell Biology; Emory University School of Medicine ; Atlanta, GA USA
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Chiba N, Shimada K, Chen S, Jones HD, Alsabeh R, Slepenkin AV, Peterson E, Crother TR, Arditi M. Mast cells play an important role in chlamydia pneumoniae lung infection by facilitating immune cell recruitment into the airway. THE JOURNAL OF IMMUNOLOGY 2015; 194:3840-51. [PMID: 25754739 DOI: 10.4049/jimmunol.1402685] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2014] [Accepted: 02/02/2015] [Indexed: 01/17/2023]
Abstract
Mast cells are known as central players in allergy and anaphylaxis, and they play a pivotal role in host defense against certain pathogens. Chlamydia pneumoniae is an important human pathogen, but it is unclear what role mast cells play during C. pneumoniae infection. We infected C57BL/6 (wild-type [WT]) and mast cell-deficient mice (Kit(W-sh/W-sh) [Wsh]) with C. pneumoniae. Wsh mice showed improved survival compared with WT mice, with fewer cells in Wsh bronchoalveolar lavage fluid (BALF), despite similar levels of cytokines and chemokines. We also found a more rapid clearance of bacteria from the lungs of Wsh mice compared with WT mice. Cromolyn, a mast cell stabilizer, reduced BALF cells and bacterial burden similar to the levels seen in Wsh mice; conversely, Compound 48/80, a mast cell degranulator, increased the number of BALF cells and bacterial burden. Histology showed that WT lungs had diffuse inflammation, whereas Wsh mice had patchy accumulations of neutrophils and perivascular accumulations of lymphocytes. Infected Wsh mice had reduced amounts of matrix metalloprotease-9 in BALF and were resistant to epithelial integral membrane protein degradation, suggesting that barrier integrity remains intact in Wsh mice. Mast cell reconstitution in Wsh mice led to enhanced bacterial growth and normal epithelial integral membrane protein degradation, highlighting the specific role of mast cells in this model. These data suggest that mast cells play a detrimental role during C. pneumoniae infection by facilitating immune cell infiltration into the airspace and providing a more favorable replicative environment for C. pneumoniae.
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Affiliation(s)
- Norika Chiba
- Division of Pediatric Infectious Diseases and Immunology, Department of Biomedical Sciences, Cedars-Sinai Medical Center and David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90048
| | - Kenichi Shimada
- Division of Pediatric Infectious Diseases and Immunology, Department of Biomedical Sciences, Cedars-Sinai Medical Center and David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90048
| | - Shuang Chen
- Division of Pediatric Infectious Diseases and Immunology, Department of Biomedical Sciences, Cedars-Sinai Medical Center and David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90048
| | - Heather D Jones
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Cedars-Sinai Medical Center and David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90048
| | - Randa Alsabeh
- Department of Pathology and Laboratory Medicine, Cedars-Sinai Medical Center and David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90048; and
| | | | - Ellena Peterson
- Department of Pathology, University of California Irvine, Irvine, CA 92697
| | - Timothy R Crother
- Division of Pediatric Infectious Diseases and Immunology, Department of Biomedical Sciences, Cedars-Sinai Medical Center and David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90048
| | - Moshe Arditi
- Division of Pediatric Infectious Diseases and Immunology, Department of Biomedical Sciences, Cedars-Sinai Medical Center and David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90048;
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33
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Alshbool FZ, Mohan S. Differential expression of claudin family members during osteoblast and osteoclast differentiation: Cldn-1 is a novel positive regulator of osteoblastogenesis. PLoS One 2014; 9:e114357. [PMID: 25479235 PMCID: PMC4257558 DOI: 10.1371/journal.pone.0114357] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2014] [Accepted: 11/06/2014] [Indexed: 01/14/2023] Open
Abstract
Claudins (Cldns), a family of 27 transmembrane proteins, represent major components of tight junctions. Aside from functioning as tight junctions, Cldns have emerging roles as regulators of cell proliferation and differentiation. While Cldns are known to be expressed and have important functions in various tissues, their expression and function in bone cells is ill-defined. In this study, the expression of Cldns was examined during osteoblast and osteoclast differentiation. The expression of Cldn-1, -7, -11, and -15 was downregulated during early stages of osteoclast differentiation, whereas Cldn-6 was upregulated. Moreover, the expression of several Cldns increased 3–7 fold in fully differentiated osteoclasts. As for osteoblasts, the expression of several Cldns was found to increase more than 10-fold during differentiation, with some peaking at early, and others at late stages. By contrast, only expression of Cldn-12, and -15 decreased during osteoblast differentiation. In subsequent studies, we focused on the role of Cldn-1 in osteoblasts as its expression was increased by more than 10 fold during osteoblast differentiation and was found to be regulated by multiple osteoregulatory agents including IGF-1 and Wnt3a. We evaluated the consequence of lentiviral shRNA-mediated knockdown of Cldn-1 on osteoblast proliferation and differentiation using MC3T3-E1 mouse osteoblasts. Cldn-1 knockdown caused a significant reduction in MC3T3-E1 cell proliferation and ALP activity. Accordingly, expression levels of cyclinD1 and ALP mRNA levels were reduced in Cldn-1 shRNA knockdown cells. We next determined if Cldn-1 regulates the expression of Runx-2 and osterix, master transcription factors of osteoblast differentiation, and found that their levels were reduced significantly as a consequence of Cldn-1 knockdown. Moreover, knocking down Cldn-1 reduced β-catenin level. In conclusion, the expression of Cldn family members during bone cell differentiation is complex and involves cell type and differentiation stage-dependent regulation. In addition, Cldn-1 is a positive regulator of osteoblast proliferation and differentiation.
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Affiliation(s)
- Fatima Z Alshbool
- Musculoskeletal Disease Center, Jerry L Pettis VA Med Ctr, Loma Linda, CA 92357, United States of America; Department of Pharmacology, Loma Linda University, Loma Linda, CA 92354, United States of America
| | - Subburaman Mohan
- Musculoskeletal Disease Center, Jerry L Pettis VA Med Ctr, Loma Linda, CA 92357, United States of America; Department of Medicine, Loma Linda University, Loma Linda, CA 92354, United States of America; Department of Biochemistry, Loma Linda University, Loma Linda, CA 92354, United States of America; Department of Physiology, Loma Linda University, Loma Linda, CA 92354, United States of America
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34
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Junctional adhesion molecule A promotes epithelial tight junction assembly to augment lung barrier function. THE AMERICAN JOURNAL OF PATHOLOGY 2014; 185:372-86. [PMID: 25438062 DOI: 10.1016/j.ajpath.2014.10.010] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2014] [Revised: 09/12/2014] [Accepted: 10/15/2014] [Indexed: 12/14/2022]
Abstract
Epithelial barrier function is maintained by tight junction proteins that control paracellular fluid flux. Among these proteins is junctional adhesion molecule A (JAM-A), an Ig fold transmembrane protein. To assess JAM-A function in the lung, we depleted JAM-A in primary alveolar epithelial cells using shRNA. In cultured cells, loss of JAM-A caused an approximately 30% decrease in transepithelial resistance, decreased expression of the tight junction scaffold protein zonula occludens 1, and disrupted junctional localization of the structural transmembrane protein claudin-18. Consistent with findings in other organs, loss of JAM-A decreased β1 integrin expression and impaired filamentous actin formation. Using a model of mild systemic endoxotemia induced by i.p. injection of lipopolysaccharide, we report that JAM-A(-/-) mice showed increased susceptibility to pulmonary edema. On injury, the enhanced susceptibility of JAM-A(-/-) mice to edema correlated with increased, transient disruption of claudin-18, zonula occludens 1, and zonula occludens 2 localization to lung tight junctions in situ along with a delay in up-regulation of claudin-4. In contrast, wild-type mice showed no change in lung tight junction morphologic features in response to mild systemic endotoxemia. These findings support a key role of JAM-A in promoting tight junction homeostasis and lung barrier function by coordinating interactions among claudins, the tight junction scaffold, and the cytoskeleton.
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Skrovanek S, DiGuilio K, Bailey R, Huntington W, Urbas R, Mayilvaganan B, Mercogliano G, Mullin JM. Zinc and gastrointestinal disease. World J Gastrointest Pathophysiol 2014; 5:496-513. [PMID: 25400994 PMCID: PMC4231515 DOI: 10.4291/wjgp.v5.i4.496] [Citation(s) in RCA: 83] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/28/2014] [Revised: 09/18/2014] [Accepted: 10/01/2014] [Indexed: 02/06/2023] Open
Abstract
This review is a current summary of the role that both zinc deficiency and zinc supplementation can play in the etiology and therapy of a wide range of gastrointestinal diseases. The recent literature describing zinc action on gastrointestinal epithelial tight junctions and epithelial barrier function is described. Zinc enhancement of gastrointestinal epithelial barrier function may figure prominently in its potential therapeutic action in several gastrointestinal diseases.
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Kage H, Flodby P, Gao D, Kim YH, Marconett CN, DeMaio L, Kim KJ, Crandall ED, Borok Z. Claudin 4 knockout mice: normal physiological phenotype with increased susceptibility to lung injury. Am J Physiol Lung Cell Mol Physiol 2014; 307:L524-36. [PMID: 25106430 DOI: 10.1152/ajplung.00077.2014] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Claudins are tight junction proteins that regulate paracellular ion permeability of epithelium and endothelium. Claudin 4 has been reported to function as a paracellular sodium barrier and is one of three major claudins expressed in lung alveolar epithelial cells (AEC). To directly assess the role of claudin 4 in regulation of alveolar epithelial barrier function and fluid homeostasis in vivo, we generated claudin 4 knockout (Cldn4 KO) mice. Unexpectedly, Cldn4 KO mice exhibited normal physiological phenotype although increased permeability to 5-carboxyfluorescein and decreased alveolar fluid clearance were noted. Cldn4 KO AEC monolayers exhibited unchanged ion permeability, higher solute permeability, and lower short-circuit current compared with monolayers from wild-type mice. Claudin 3 and 18 expression was similar between wild-type and Cldn4 KO alveolar epithelial type II cells. In response to either ventilator-induced lung injury or hyperoxia, claudin 4 expression was markedly upregulated in wild-type mice, whereas Cldn4 KO mice showed greater degrees of lung injury. RNA sequencing, in conjunction with differential expression and upstream analysis after ventilator-induced lung injury, suggested Egr1, Tnf, and Il1b as potential mediators of increased lung injury in Cldn4 KO mice. These results demonstrate that claudin 4 has little effect on normal lung physiology but may function to protect against acute lung injury.
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Affiliation(s)
- Hidenori Kage
- Will Rogers Institute Pulmonary Research Center, Division of Pulmonary, Critical Care, and Sleep Medicine, Department of Medicine
| | - Per Flodby
- Will Rogers Institute Pulmonary Research Center, Division of Pulmonary, Critical Care, and Sleep Medicine, Department of Medicine
| | - Danping Gao
- Will Rogers Institute Pulmonary Research Center, Division of Pulmonary, Critical Care, and Sleep Medicine, Department of Medicine
| | - Yong Ho Kim
- Will Rogers Institute Pulmonary Research Center, Division of Pulmonary, Critical Care, and Sleep Medicine, Department of Medicine
| | - Crystal N Marconett
- Departments of Surgery and Biochemistry and Molecular Biology, Norris Comprehensive Cancer Center
| | - Lucas DeMaio
- Will Rogers Institute Pulmonary Research Center, Division of Pulmonary, Critical Care, and Sleep Medicine, Department of Medicine
| | - Kwang-Jin Kim
- Will Rogers Institute Pulmonary Research Center, Division of Pulmonary, Critical Care, and Sleep Medicine, Department of Medicine, Departments of Physiology and Biophysics and Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California; Department of Biomedical Engineering and
| | - Edward D Crandall
- Will Rogers Institute Pulmonary Research Center, Division of Pulmonary, Critical Care, and Sleep Medicine, Department of Medicine, Pathology, Keck School of Medicine, University of Southern California; Mork Family Department of Chemical Engineering and Materials Science, Viterbi School of Engineering, University of Southern California, Los Angeles, California
| | - Zea Borok
- Will Rogers Institute Pulmonary Research Center, Division of Pulmonary, Critical Care, and Sleep Medicine, Department of Medicine, Biochemistry and Molecular Biology, Norris Comprehensive Cancer Center,
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Abstract
The imbalance between bone formation and resorption during bone remodeling has been documented to be a major factor in the pathogenesis of osteoporosis. Recent evidence suggests a significant role for the tight junction proteins, Claudins (Cldns), in the regulation of bone remodeling processes. In terms of function, whereas Cldns act "canonically" as key determinants of paracellular permeability, there is considerable recent evidence to suggest that Cldns also participate in cell signaling, ie, a "noncanonical function". To this end, Cldns have been shown to regulate cell proliferation, differentiation, and gene expression in a variety of cell types. The present review will discuss Cldns' structure, their expression profile, regulation of expression, and their canonical and non- canonical functions in general with special emphasis on bone cells. In order to shed light on the noncanonical functions of Cldns in bone, we will highlight the role of Cldn-18 in regulating bone resorption and osteoclast differentiation. Collectively, we hope to provide a framework for guiding future research on understanding how Cldns modulate osteoblast and osteoclast function and overall bone homeostasis. Such studies should provide valuable insights into the pathogenesis of osteoporosis, and may highlight Cldns as novel targets for the diagnosis and therapeutic management of osteoporosis.
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Affiliation(s)
- Fatima Z Alshbool
- Musculoskeletal Disease Center (F.Z.A., S.M.), Jerry L. Pettis VA Medical Center, Loma Linda, CA 92357; Departments of Medicine (S.M.), Biochemistry (S.M.), Physiology (S.M.), and Pharmacology (F.Z.A., S.M.), Loma Linda University, Loma Linda, California 92354
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Cui J, Wang H, Liu S, Zhu L, Qiu X, Jiang Z, Wang X, Liu Z. SNP discovery from transcriptome of the swimbladder of Takifugu rubripes. PLoS One 2014; 9:e92502. [PMID: 24651578 PMCID: PMC3961390 DOI: 10.1371/journal.pone.0092502] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2013] [Accepted: 02/23/2014] [Indexed: 12/24/2022] Open
Abstract
Single nucleotide polymorphisms (SNPs) have become the marker of choice for genome-wide association studies in many species. High-throughput sequencing of RNA was developed primarily to analyze global gene expression, while it is an efficient way to discover SNPs from the expressed genes. In this study, we conducted transcriptome sequencing of the swimbladder of Takifugu rubripes using Illumina HiSeq2000 platform to identify gene-associated SNPs in the swimbladder. A total of 30,312,181 unique-mapped-reads were obtained from 44,736,850 raw reads. A total of 62,270 putative SNPs were discovered, which were located in 11,306 expressed genes and 2,246 scaffolds. The average minor allele frequency (MAF) of the SNPs was 0.26. GO and KEGG pathway analysis were conducted to analyze the genes containing SNPs. Validation of selected SNPs revealed that 54% of SNPs (26/48) were true SNPs. The results suggest that RNA-Seq is an efficient and cost-effective approach to discover gene-associated SNPs. In this study, a large number of SNPs were identified and these data will be useful resources for population genetic study, evolution analysis, resource assessment, genetic linkage analysis and genome-wide association studies.
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Affiliation(s)
- Jun Cui
- Key Laboratory of Mariculture & Stock Enhancement in North China's Sea, Ministry of Agriculture, Dalian Ocean University, Dalian, China
| | - Hongdi Wang
- Key Laboratory of Mariculture & Stock Enhancement in North China's Sea, Ministry of Agriculture, Dalian Ocean University, Dalian, China
| | - Shikai Liu
- The Fish Molecular Genetics and Biotechnology Laboratory, Aquatic Genomics Unit, School of Fisheries, Aquaculture and Aquatic Sciences and Program of Cell and Molecular Biosciences, Auburn University, Auburn, Alabama, United States of America
| | - Lifu Zhu
- School of Environmental and Chemical Engineering, Dalian Jiaotong University, Dalian, China
| | - Xuemei Qiu
- Key Laboratory of Mariculture & Stock Enhancement in North China's Sea, Ministry of Agriculture, Dalian Ocean University, Dalian, China
| | - Zhiqiang Jiang
- Key Laboratory of Mariculture & Stock Enhancement in North China's Sea, Ministry of Agriculture, Dalian Ocean University, Dalian, China
- * E-mail: (ZJ); (XW); (ZL)
| | - Xiuli Wang
- Key Laboratory of Mariculture & Stock Enhancement in North China's Sea, Ministry of Agriculture, Dalian Ocean University, Dalian, China
- * E-mail: (ZJ); (XW); (ZL)
| | - Zhanjiang Liu
- The Fish Molecular Genetics and Biotechnology Laboratory, Aquatic Genomics Unit, School of Fisheries, Aquaculture and Aquatic Sciences and Program of Cell and Molecular Biosciences, Auburn University, Auburn, Alabama, United States of America
- * E-mail: (ZJ); (XW); (ZL)
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Dittmann I, Amasheh M, Krug SM, Markov AG, Fromm M, Amasheh S. Laurate Permeates the Paracellular Pathway for Small Molecules in the Intestinal Epithelial Cell Model HT-29/B6 via Opening the Tight Junctions by Reversible Relocation of Claudin-5. Pharm Res 2014; 31:2539-48. [DOI: 10.1007/s11095-014-1350-2] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2013] [Accepted: 02/24/2014] [Indexed: 12/11/2022]
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Cui J, Liu S, Zhang B, Wang H, Sun H, Song S, Qiu X, Liu Y, Wang X, Jiang Z, Liu Z. Transciptome analysis of the gill and swimbladder of Takifugu rubripes by RNA-Seq. PLoS One 2014; 9:e85505. [PMID: 24454879 PMCID: PMC3894188 DOI: 10.1371/journal.pone.0085505] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2013] [Accepted: 11/28/2013] [Indexed: 11/25/2022] Open
Abstract
The fish gill, as one of the mucosal barriers, plays an important role in mucosal immune response. The fish swimbladder functions for regulating buoyancy. The fish swimbladder has long been postulated as a homologous organ of the tetrapod lung, but the molecular evidence is scarce. In order to provide new information that is complementary to gill immune genes, initiate new research directions concerning the genetic basis of the gill immune response and understand the molecular function of swimbladder as well as its relationship with lungs, transcriptome analysis of the fugu Takifugu rubripes gill and swimbladder was carried out by RNA-Seq. Approximately 55,061,524 and 44,736,850 raw sequence reads from gill and swimbladder were generated, respectively. Gene ontology (GO) and KEGG pathway analysis revealed diverse biological functions and processes. Transcriptome comparison between gill and swimbladder resulted in 3,790 differentially expressed genes, of which 1,520 were up-regulated in the swimbladder while 2,270 were down-regulated. In addition, 406 up regulated isoforms and 296 down regulated isoforms were observed in swimbladder in comparison to gill. By the gene enrichment analysis, the three immune-related pathways and 32 immune-related genes in gill were identified. In swimbladder, five pathways including 43 swimbladder-enriched genes were identified. This work should set the foundation for studying immune-related genes for the mucosal immunity and provide genomic resources to study the relatedness of the fish swimbladder and mammalian lung.
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Affiliation(s)
- Jun Cui
- Key Laboratory of Mariculture and Stock Enhancement in North China's Sea, Ministry of Agriculture, Dalian Ocean University, Dalian, China
| | - Shikai Liu
- The Fish Molecular Genetics and Biotechnology Laboratory, Department of Fisheries and Allied Aquacultures and Program of Cell and Molecular Biosciences, Aquatic Genomics Unit, Auburn University, Auburn, Alabama, United States of America
| | - Bing Zhang
- Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing, China
| | - Hongdi Wang
- Key Laboratory of Mariculture and Stock Enhancement in North China's Sea, Ministry of Agriculture, Dalian Ocean University, Dalian, China
| | - Hongjuan Sun
- Key Laboratory of Mariculture and Stock Enhancement in North China's Sea, Ministry of Agriculture, Dalian Ocean University, Dalian, China
| | - Shuhui Song
- Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing, China
| | - Xuemei Qiu
- Key Laboratory of Mariculture and Stock Enhancement in North China's Sea, Ministry of Agriculture, Dalian Ocean University, Dalian, China
| | - Yang Liu
- Key Laboratory of Mariculture and Stock Enhancement in North China's Sea, Ministry of Agriculture, Dalian Ocean University, Dalian, China
| | - Xiuli Wang
- Key Laboratory of Mariculture and Stock Enhancement in North China's Sea, Ministry of Agriculture, Dalian Ocean University, Dalian, China
- * E-mail: (XW); (ZJ); (ZL)
| | - Zhiqiang Jiang
- Key Laboratory of Mariculture and Stock Enhancement in North China's Sea, Ministry of Agriculture, Dalian Ocean University, Dalian, China
- * E-mail: (XW); (ZJ); (ZL)
| | - Zhanjiang Liu
- The Fish Molecular Genetics and Biotechnology Laboratory, Department of Fisheries and Allied Aquacultures and Program of Cell and Molecular Biosciences, Aquatic Genomics Unit, Auburn University, Auburn, Alabama, United States of America
- * E-mail: (XW); (ZJ); (ZL)
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Hata M, Yamanegi K, Yamada N, Ohyama H, Yukitatsu Y, Nakasho K, Okamura H, Terada N. Estrogen decreases the expression of claudin-5 in vascular endothelial cells in the murine uterus. Endocr J 2014; 61:705-15. [PMID: 24759004 DOI: 10.1507/endocrj.ej13-0442] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Vascular endothelial (VE)-cadherin and claudin-5 are major components of the adherens and tight junctions of vascular endothelial cells, respectively, and decreases in their expression are associated with increases in endothelial paracellular permeability. In the uterus, estrogen induces endometrial edema. However, the in vivo effect of estrogen on endothelial paracellular permeability is unknown. Therefore, we studied the expression of VE-cadherin and claudin-5 in vascular endothelial cells in murine uteri stimulated by estrogen or progesterone. Ovariectomized mature mice were injected with estradiol-17β (1 μg/mouse) or progesterone (1 mg/mouse) at intervals of 24 hours for 6 days. The frozen transverse sections of the uteri of these mice and untreated mice were stained for CD31 (vascular endothelial cell marker) plus VE-cadherin or claudin-5 using a double-immunofluorescence method. Then, the percentages of VE-cadherin- or claudin-5-positive vessels among CD31-positive vessels were examined in the uterine endometria. VE-cadherin and claudin-5 were expressed in most CD31-positive vessels in the endometria of the untreated mice. Progesterone did not affect the expression of both VE-cadherin and claudin-5 and estradiol-17β also did not affect the VE-cadherin expression, but estradiol-17β significantly decreased the claudin-5 expression. This decreasing effect of estradiol-17β was detected from 24 hours later when the water content per a uterus significantly increased. The present study indicates that estrogen, but not progesterone, decreases the expression of claudin-5 in vascular endothelial cells in the murine uterine endometrium from 24 hours later, suggesting that the decrease in the claudin-5 expression contributes to the endometrial edema late after the estrogen stimulation.
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Affiliation(s)
- Masaki Hata
- Department of Pathology, Hyogo College of Medicine, Nishinomiya 663-8501, Japan
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Arsenic compromises conducting airway epithelial barrier properties in primary mouse and immortalized human cell cultures. PLoS One 2013; 8:e82970. [PMID: 24349408 PMCID: PMC3857810 DOI: 10.1371/journal.pone.0082970] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2013] [Accepted: 11/08/2013] [Indexed: 12/31/2022] Open
Abstract
Arsenic is a lung toxicant that can lead to respiratory illness through inhalation and ingestion, although the most common exposure is through contaminated drinking water. Lung effects reported from arsenic exposure include lung cancer and obstructive lung disease, as well as reductions in lung function and immune response. As part of their role in innate immune function, airway epithelial cells provide a barrier that protects underlying tissue from inhaled particulates, pathogens, and toxicants frequently found in inspired air. We evaluated the effects of a five-day exposure to environmentally relevant levels of arsenic {<4μM [~300 μg/L (ppb)] as NaAsO2} on airway epithelial barrier function and structure. In a primary mouse tracheal epithelial (MTE) cell model we found that both micromolar (3.9 μM) and submicromolar (0.8 μM) arsenic concentrations reduced transepithelial resistance, a measure of barrier function. Immunofluorescent staining of arsenic-treated MTE cells showed altered patterns of localization of the transmembrane tight junction proteins claudin (Cl) Cl-1, Cl-4, Cl-7 and occludin at cell-cell contacts when compared with untreated controls. To better quantify arsenic-induced changes in tight junction transmembrane proteins we conducted arsenic exposure experiments with an immortalized human bronchial epithelial cell line (16HBE14o-). We found that arsenic exposure significantly increased the protein expression of Cl-4 and occludin as well as the mRNA levels of Cl-4 and Cl-7 in these cells. Additionally, arsenic exposure resulted in altered phosphorylation of occludin. In summary, exposure to environmentally relevant levels of arsenic can alter both the function and structure of airway epithelial barrier constituents. These changes likely contribute to the observed arsenic-induced loss in basic innate immune defense and increased infection in the airway.
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The degradation of airway tight junction protein under acidic conditions is probably mediated by transient receptor potential vanilloid 1 receptor. Biosci Rep 2013; 33:BSR20130087. [PMID: 24073800 PMCID: PMC3814059 DOI: 10.1042/bsr20130087] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Acidic airway microenvironment is one of the representative pathophysiological features of chronic inflammatory respiratory diseases. Epithelial barrier function is maintained by TJs (tight junctions), which act as the first physical barrier against the inhaled substances and pathogens of airway. As previous studies described, acid stress caused impaired epithelial barriers and led the hyperpermeability of epithelium. However, the specific mechanism is still unclear. We have showed previously the existence of TRPV (transient receptor potential vanilloid) 1 channel in airway epithelium, as well as its activation by acidic stress in 16HBE cells. In this study, we explored the acidic stress on airway barrier function and TJ proteins in vitro with 16HBE cell lines. Airway epithelial barrier function was determined by measuring by TER (trans-epithelial electrical resistance). TJ-related protein [claudin-1, claudin-3, claudin-4, claudin-5, claudin-7 and ZO-1 (zonula occluden 1)] expression was examined by western blotting of insoluble fractions of cell extraction. The localization of TJ proteins were visualized by immunofluorescent staining. Interestingly, stimulation by pH 6.0 for 8 h slightly increased the epithelial resistance in 16HBE cells insignificantly. However, higher concentration of hydrochloric acid (lower than pH 5.0) did reduce the airway epithelial TER of 16HBE cells. The decline of epithelial barrier function induced by acidic stress exhibited a TRPV1-[Ca2+]i-dependent pathway. Of the TJ proteins, claudin-3 and claudin-4 seemed to be sensitive to acidic stress. The degradation of claudin-3 and claudin-4 induced by acidic stress could be attenuated by the specific TRPV1 blocker or intracellular Ca2+ chelator BAPTA/AM [1,2-bis-(o-aminophenoxy)ethane-N,N,N',N'-tetra-acetic acid tetrakis(acetoxymethyl ester)].
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Zarogoulidis P, Kioumis I, Porpodis K, Spyratos D, Tsakiridis K, Huang H, Li Q, Turner JF, Browning R, Hohenforst-Schmidt W, Zarogoulidis K. Clinical experimentation with aerosol antibiotics: current and future methods of administration. DRUG DESIGN DEVELOPMENT AND THERAPY 2013; 7:1115-34. [PMID: 24115836 PMCID: PMC3793595 DOI: 10.2147/dddt.s51303] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Currently almost all antibiotics are administered by the intravenous route. Since several systems and situations require more efficient methods of administration, investigation and experimentation in drug design has produced local treatment modalities. Administration of antibiotics in aerosol form is one of the treatment methods of increasing interest. As the field of drug nanotechnology grows, new molecules have been produced and combined with aerosol production systems. In the current review, we discuss the efficiency of aerosol antibiotic studies along with aerosol production systems. The different parts of the aerosol antibiotic methodology are presented. Additionally, information regarding the drug molecules used is presented and future applications of this method are discussed.
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Affiliation(s)
- Paul Zarogoulidis
- Pulmonary Department, G Papanikolaou General Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece ; Department of Interventional Pneumology, Ruhrlandklinik, West German Lung Center, University Hospital, University Duisburg-Essen, Essen, Germany
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Abstract
The distal airways are covered with a heterogeneous layer of cells known as the alveolar epithelium. Alveolar epithelial cells provide the major barrier between the airspace and fluid filled tissue compartments. As such, regulation of the alveolar epithelium is critical to maintain a healthy lung and for optimal gas exchange. In this chapter, we discuss functional roles for alveolar epithelial cells with particular emphasis on intercellular junctions and communication. As a thin layer of cells directly exposed to atmospheric oxygen, alveoli are particularly sensitive to oxidant insults. Alcohol significantly diminishes the normal antioxidant reserves of the alveolar epithelium, thereby rendering it sensitized for an exaggerated damage response to acute and chronic injuries. The effects of alcohol on alveolar epithelia are discussed along with open questions and potential therapeutic targets to prevent the pathophysiology of alcoholic lung disease.
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Zarogoulidis P, Kioumis I, Ritzoulis C, Petridis D, Darwiche K, Porpodis K, Spyratos D, Parrish S, Browning R, Li Q, Turner JF, Freitag L, Zarogoulidis K. New insights in the production of aerosol antibiotics. Evaluation of the optimal aerosol production system for ampicillin-sulbactam, meropenem, ceftazidime, cefepime and piperacillin-tazobactam. Int J Pharm 2013; 455:182-8. [PMID: 23891745 DOI: 10.1016/j.ijpharm.2013.07.040] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2013] [Revised: 07/15/2013] [Accepted: 07/17/2013] [Indexed: 02/04/2023]
Abstract
BACKGROUND Several aerosol antibiotics are on the market and several others are currently being evaluated. Aim of the study was to evaluate the aerosol droplet size of five different antibiotics for future evaluation as an aerosol administration. MATERIALS AND METHODS The nebulizers Sunmist(®), Maxineb(®) and Invacare(®) were used in combination with four different "small <6 ml" residual cups and two "large <10 ml" with different loadings 2-4-6-8 ml (8 ml only for large residual cups) with five different antibiotic drugs (ampicilln-sulbactam, meropenem, ceftazidime, cefepime and piperacillin-tazobactam). The Mastersizer 2000 (Malvern) was used to evaluate the produced droplet size from each combination RESULTS Significant effect on the droplet size produced the different antibiotic (F=96.657, p<0.001) and the residual cup design (F=68.535, p<0.001) but not the different loading amount (p=0.127) and the nebulizer (p=0.715). Interactions effects were found significant only between antibiotic and residual cup (F=16.736, p<0.001). No second order interactions were found statistically significant. CONCLUSION Our results firstly indicate us indirectly that the chemical formulation of the drug is the main factor affecting the produced droplet size and secondly but closely the residual cup design.
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Affiliation(s)
- Paul Zarogoulidis
- Pulmonary Department-Oncology Unit, G. Papanikolaou General Hospital, Aristotle Univesrity of Thessaloniki, Thessaloniki, Greece.
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Oxidative stress mediates the disruption of airway epithelial tight junctions through a TRPM2-PLCγ1-PKCα signaling pathway. Int J Mol Sci 2013; 14:9475-86. [PMID: 23629676 PMCID: PMC3676794 DOI: 10.3390/ijms14059475] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2013] [Revised: 03/18/2013] [Accepted: 04/16/2013] [Indexed: 11/16/2022] Open
Abstract
Oxidative stress has been implicated as an important contributing factor in the pathogenesis of several pulmonary inflammatory diseases. Previous studies have indicated a relationship between oxidative stress and the attenuation of epithelial tight junctions (TJs). In Human Bronchial Epithelial-16 cells (16HBE), we demonstrated the degradation of zonula occludens-1 (ZO-1), and claudin-2 exhibited a great dependence on the activation of the transient receptor potential melastatin (TRPM) 2 channel, phospholipase Cγ1 (PLCγ1) and the protein kinase Cα (PKCα) signaling cascade.
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Abstract
Claudins are tight junction membrane proteins that are expressed in epithelia and endothelia and form paracellular barriers and pores that determine tight junction permeability. This review summarizes our current knowledge of this large protein family and discusses recent advances in our understanding of their structure and physiological functions.
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Affiliation(s)
- Dorothee Günzel
- Department of Clinical Physiology, Charité, Campus Benjamin Franklin, Berlin, Germany
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Yukitatsu Y, Hata M, Yamanegi K, Yamada N, Ohyama H, Nakasho K, Kojima Y, Oka H, Tsuzuki K, Sakagami M, Terada N. Decreased expression of VE-cadherin and claudin-5 and increased phosphorylation of VE-cadherin in vascular endothelium in nasal polyps. Cell Tissue Res 2013; 352:647-57. [DOI: 10.1007/s00441-013-1583-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2012] [Accepted: 02/04/2013] [Indexed: 12/27/2022]
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50
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Regulation of Tight Junctions for Therapeutic Advantages. CANCER METASTASIS - BIOLOGY AND TREATMENT 2013. [DOI: 10.1007/978-94-007-6028-8_9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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