1
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Ljungholm PL, Ermund A, Söderlund Garsveden MM, Pettersson VL, Gustafsson JK. The anion exchanger slc26a3 regulates colonic mucus expansion during steady state and in response to prostaglandin E 2, while Cftr regulates de novo mucus release in response to carbamylcholine. Pflugers Arch 2024; 476:1209-1219. [PMID: 38829391 DOI: 10.1007/s00424-024-02975-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2024] [Revised: 05/02/2024] [Accepted: 05/19/2024] [Indexed: 06/05/2024]
Abstract
The intestinal epithelium is covered by mucus that protects the tissue from the luminal content. Studies have shown that anion secretion via the cystic fibrosis conductance regulator (Cftr) regulates mucus formation in the small intestine. However, mechanisms regulating mucus formation in the colon are less understood. The aim of this study was to explore the role of anion transport in the regulation of mucus formation during steady state and in response to carbamylcholine (CCh) and prostaglandin E2 (PGE2). The broad-spectrum anion transport inhibitor 4,4'-diisothiocyanatostilbene-2,2'-disulfonate (DIDS), CftrdF508 (CF) mice, and the slc26a3 inhibitor SLC26A3-IN-2 were used to inhibit anion transport. In the distal colon, steady-state mucus expansion was reduced by SLC26A3-IN-2 and normal in CF mice. PGE2 stimulated mucus expansion without de novo mucus release in wild type (WT) and CF colon via slc26a3 sensitive mechanisms, while CCh induced de novo mucus secretion in WT but not in CF colon. However, when added simultaneously, CCh and PGE2 stimulated de novo mucus secretion in the CF colon via DIDS-sensitive pathways. A similar response was observed in CF ileum that responded to CCh and PGE2 with DIDS-sensitive de novo mucus secretion. In conclusion, this study suggests that slc26a3 regulates colonic mucus expansion, while Cftr regulates CCh-induced de novo mucus secretion from ileal and distal colon crypts. Furthermore, these findings demonstrate that in the absence of a functional Cftr channel, parallel stimulation with CCh and PGE2 activates additional anion transport processes that help release mucus from intestinal goblet cells.
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Affiliation(s)
- Penny L Ljungholm
- Department of Physiology, University of Gothenburg, Medicinaregatan 11, Box 432, 405 30, Gothenburg, Sweden
| | - Anna Ermund
- Department of Medical Chemistry and Cell Biology, University of Gothenburg, Gothenburg, Sweden
| | | | - Victor L Pettersson
- Department of Physiology, University of Gothenburg, Medicinaregatan 11, Box 432, 405 30, Gothenburg, Sweden
| | - Jenny K Gustafsson
- Department of Physiology, University of Gothenburg, Medicinaregatan 11, Box 432, 405 30, Gothenburg, Sweden.
- Department of Medical Chemistry and Cell Biology, University of Gothenburg, Gothenburg, Sweden.
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2
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Meng X, Ford RC. Investigation of F508del CFTR unfolding and a search for stabilizing small molecules. Arch Biochem Biophys 2024; 758:110050. [PMID: 38876247 DOI: 10.1016/j.abb.2024.110050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Revised: 03/31/2024] [Accepted: 04/30/2024] [Indexed: 06/16/2024]
Abstract
Mutation of phenylalanine at position 508 in the cystic fibrosis transmembrane conductance regulator (F508del CFTR) yields a protein unstable at physiological temperatures that is rapidly degraded in the cell. This mutation is present in about 90% of cystic fibrosis patients, hence there is great interest in compounds reversing its instability. We have previously reported the expression of the mutated protein at low temperature and its purification in detergent. Here we describe the use of the protein to screen compounds present in a library of Federal Drug Administration (FDA) - approved drugs and also in a small natural product library. The kinetics of unfolding of F508del CFTR at 37 °C were probed by the increase in solvent-exposed cysteine residues accessible to a fluorescent reporter molecule. This occurred in a bi-exponential manner with a major (≈60%) component of half-life around 5 min and a minor component of around 60 min. The faster kinetics match those observed for loss of channel activity of F508del CFTR in cells at 37 °C. Most compounds tested had no effect on the fluorescence increase, but some were identified that significantly slowed the kinetics. The general properties of these compounds, and any likely mechanisms for inducing stability in purified CFTR are discussed. These experimental data may be useful for artificial intelligence - aided design of CFTR-specific drugs and in the identification of stabilizing additives for membrane proteins (in general).
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Affiliation(s)
- Xin Meng
- University of Manchester, School of Biological Sciences, Oxford Road, Manchester, M13 9PL, UK; The Francis Crick Institute, Cellular Degradation Systems Lab, 1 Midland Road, London, NW1 1AT, UK
| | - Robert C Ford
- University of Manchester, School of Biological Sciences, Oxford Road, Manchester, M13 9PL, UK.
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3
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Harris ES, McIntire HJ, Mazur M, Schulz-Hildebrandt H, Leung HM, Tearney GJ, Krick S, Rowe SM, Barnes JW. Reduced sialylation of airway mucin impairs mucus transport by altering the biophysical properties of mucin. Sci Rep 2024; 14:16568. [PMID: 39019950 PMCID: PMC11255327 DOI: 10.1038/s41598-024-66510-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2024] [Accepted: 07/02/2024] [Indexed: 07/19/2024] Open
Abstract
Mucus stasis is a pathologic hallmark of muco-obstructive diseases, including cystic fibrosis (CF). Mucins, the principal component of mucus, are extensively modified with hydroxyl (O)-linked glycans, which are largely terminated by sialic acid. Sialic acid is a negatively charged monosaccharide and contributes to the biochemical/biophysical properties of mucins. Reports suggest that mucin sialylation may be altered in CF; however, the consequences of reduced sialylation on mucus clearance have not been fully determined. Here, we investigated the consequences of reduced sialylation on the charge state and conformation of the most prominent airway mucin, MUC5B, and defined the functional consequences of reduced sialylation on mucociliary transport (MCT). Reduced sialylation contributed to a lower charged MUC5B form and decreased polymer expansion. The inhibition of total mucin sialylation de novo impaired MCT in primary human bronchial epithelial cells and rat airways, and specific α-2,3 sialylation blockade was sufficient to recapitulate these findings. Finally, we show that ST3 beta-galactoside alpha-2,3-sialyltransferase (ST3Gal1) expression is downregulated in CF and partially restored by correcting CFTR via Elexacaftor/Tezacaftor/Ivacaftor treatment. Overall, this study demonstrates the importance of mucin sialylation in mucus clearance and identifies decreased sialylation by ST3Gal1 as a possible therapeutic target in CF and potentially other muco-obstructive diseases.
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Affiliation(s)
- Elex S Harris
- Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham, 1900 University Blvd. Tinsley Harrison Tower, Suite 422, Birmingham, AL, 35294, USA
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Hannah J McIntire
- Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham, 1900 University Blvd. Tinsley Harrison Tower, Suite 422, Birmingham, AL, 35294, USA
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Marina Mazur
- Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham, 1900 University Blvd. Tinsley Harrison Tower, Suite 422, Birmingham, AL, 35294, USA
| | | | - Hui Min Leung
- Massachusetts General Hospital, Boston, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - Guillermo J Tearney
- Massachusetts General Hospital, Boston, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - Stefanie Krick
- Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham, 1900 University Blvd. Tinsley Harrison Tower, Suite 422, Birmingham, AL, 35294, USA
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Steven M Rowe
- Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham, 1900 University Blvd. Tinsley Harrison Tower, Suite 422, Birmingham, AL, 35294, USA.
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA.
- Departments of Pediatrics and Cell Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL, USA.
| | - Jarrod W Barnes
- Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham, 1900 University Blvd. Tinsley Harrison Tower, Suite 422, Birmingham, AL, 35294, USA.
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA.
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4
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Sousa AA, Hemez C, Lei L, Traore S, Kulhankova K, Newby GA, Doman JL, Oye K, Pandey S, Karp PH, McCray PB, Liu DR. Systematic optimization of prime editing for the efficient functional correction of CFTR F508del in human airway epithelial cells. Nat Biomed Eng 2024:10.1038/s41551-024-01233-3. [PMID: 38987629 DOI: 10.1038/s41551-024-01233-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2023] [Accepted: 06/12/2024] [Indexed: 07/12/2024]
Abstract
Prime editing (PE) enables precise and versatile genome editing without requiring double-stranded DNA breaks. Here we describe the systematic optimization of PE systems to efficiently correct human cystic fibrosis (CF) transmembrane conductance regulator (CFTR) F508del, a three-nucleotide deletion that is the predominant cause of CF. By combining six efficiency optimizations for PE-engineered PE guide RNAs, the PEmax architecture, the transient expression of a dominant-negative mismatch repair protein, strategic silent edits, PE6 variants and proximal 'dead' single-guide RNAs-we increased correction efficiencies for CFTR F508del from less than 0.5% in HEK293T cells to 58% in immortalized bronchial epithelial cells (a 140-fold improvement) and to 25% in patient-derived airway epithelial cells. The optimizations also resulted in minimal off-target editing, in edit-to-indel ratios 3.5-fold greater than those achieved by nuclease-mediated homology-directed repair, and in the functional restoration of CFTR ion channels to over 50% of wild-type levels (similar to those achieved via combination treatment with elexacaftor, tezacaftor and ivacaftor) in primary airway cells. Our findings support the feasibility of a durable one-time treatment for CF.
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Affiliation(s)
- Alexander A Sousa
- Merkin Institute of Transformative Technologies in Healthcare, The Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA
- Howard Hughes Medical Institute, Harvard University, Cambridge, MA, USA
| | - Colin Hemez
- Merkin Institute of Transformative Technologies in Healthcare, The Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA
- Howard Hughes Medical Institute, Harvard University, Cambridge, MA, USA
| | - Lei Lei
- Stead Family Department of Pediatrics and Pappajohn Biomedical Institute, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, IA, USA
| | - Soumba Traore
- Stead Family Department of Pediatrics and Pappajohn Biomedical Institute, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, IA, USA
| | - Katarina Kulhankova
- Stead Family Department of Pediatrics and Pappajohn Biomedical Institute, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, IA, USA
| | - Gregory A Newby
- Merkin Institute of Transformative Technologies in Healthcare, The Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA
- Howard Hughes Medical Institute, Harvard University, Cambridge, MA, USA
- Department of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, USA
| | - Jordan L Doman
- Merkin Institute of Transformative Technologies in Healthcare, The Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA
- Howard Hughes Medical Institute, Harvard University, Cambridge, MA, USA
| | - Keyede Oye
- Merkin Institute of Transformative Technologies in Healthcare, The Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA
- Howard Hughes Medical Institute, Harvard University, Cambridge, MA, USA
| | - Smriti Pandey
- Merkin Institute of Transformative Technologies in Healthcare, The Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA
- Howard Hughes Medical Institute, Harvard University, Cambridge, MA, USA
| | - Philip H Karp
- Department of Internal Medicine and Pappajohn Biomedical Institute, Roy J. and Lucille A. Carver College of Medicine, Iowa City, IA, USA
- Howard Hughes Medical Institute, University of Iowa, Iowa City, IA, USA
| | - Paul B McCray
- Stead Family Department of Pediatrics and Pappajohn Biomedical Institute, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, IA, USA
| | - David R Liu
- Merkin Institute of Transformative Technologies in Healthcare, The Broad Institute of MIT and Harvard, Cambridge, MA, USA.
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA.
- Howard Hughes Medical Institute, Harvard University, Cambridge, MA, USA.
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5
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Rulff H, Schmidt RF, Wei LF, Fentker K, Kerkhoff Y, Mertins P, Mall MA, Lauster D, Gradzielski M. Comprehensive Characterization of the Viscoelastic Properties of Bovine Submaxillary Mucin (BSM) Hydrogels and the Effect of Additives. Biomacromolecules 2024; 25:4014-4029. [PMID: 38832927 PMCID: PMC11238336 DOI: 10.1021/acs.biomac.4c00153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2024]
Abstract
This study presents a comprehensive characterization of the viscoelastic and structural properties of bovine submaxillary mucin (BSM), which is widely used as a commercial source to conduct mucus-related research. We conducted concentration studies of BSM and examined the effects of various additives, NaCl, CaCl2, MgCl2, lysozyme, and DNA, on its rheological behavior. A notable connection between BSM concentration and viscoelastic properties was observed, particularly under varying ionic conditions. The rheological spectra could be well described by a fractional Kelvin-Voigt model with a minimum of model parameters. A detailed proteomics analysis provided insight into the protein, especially mucin composition within BSM, showing MUC19 as the main component. Cryo-scanning electron microscopy enabled the visualization of the porous BSM network structure. These investigations give us a more profound comprehension of the BSM properties, especially those pertaining to viscoelasticity, and how they are influenced by concentration and environmental conditions, aspects relevant to the field of mucus research.
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Affiliation(s)
- Hanna Rulff
- Institute of Chemistry, Technische Universität Berlin, 10623 Berlin, Germany
| | - Robert F Schmidt
- Institute of Chemistry, Technische Universität Berlin, 10623 Berlin, Germany
| | - Ling-Fang Wei
- Institute of Pharmacy, Freie Universität Berlin, 14195 Berlin, Germany
| | - Kerstin Fentker
- Proteomics Platform, Max-Delbrück-Center for Molecular Medicine, 13125 Berlin, Germany
- Institute of Chemistry and Biochemistry, Freie Universität Berlin, 14195 Berlin, Germany
| | - Yannic Kerkhoff
- Research Center of Electron Microscopy, Institute of Chemistry and Biochemistry, Freie Universität Berlin, 14195 Berlin, Germany
| | - Philipp Mertins
- Proteomics Platform, Max-Delbrück-Center for Molecular Medicine, 13125 Berlin, Germany
- Berlin Institute of Health at Charite, Universitätsmedizin Berlin, 10178 Berlin, Germany
| | - Marcus A Mall
- Berlin Institute of Health at Charite, Universitätsmedizin Berlin, 10178 Berlin, Germany
- Department of Pediatric Respiratory Medicine, Immunology and Critical Care Medicine, Charite, Universitätsmedizin Berlin, 13353 Berlin, Germany
- German Centre for Lung Research (DZL), Associated Partner Site, 13353 Berlin, Germany
| | - Daniel Lauster
- Institute of Pharmacy, Freie Universität Berlin, 14195 Berlin, Germany
| | - Michael Gradzielski
- Institute of Chemistry, Technische Universität Berlin, 10623 Berlin, Germany
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6
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Stanforth KJ, Zakhour MI, Chater PI, Wilcox MD, Adamson B, Robson NA, Pearson JP. The MUC2 Gene Product: Polymerisation and Post-Secretory Organisation-Current Models. Polymers (Basel) 2024; 16:1663. [PMID: 38932019 PMCID: PMC11207715 DOI: 10.3390/polym16121663] [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: 05/22/2024] [Revised: 06/03/2024] [Accepted: 06/10/2024] [Indexed: 06/28/2024] Open
Abstract
MUC2 mucin, the primary gel-forming component of intestinal mucus, is well researched and a model of polymerisation and post-secretory organisation has been published previously. Recently, several significant developments have been made which either introduce new ideas or challenge previous theories. New ideas include an overhaul of the MUC2 C-terminal globular structure which is proposed to harbour several previously unobserved domains, and include a site for an extra intermolecular disulphide bridge dimer between the cysteine 4379 of adjacent MUC2 C-termini. MUC2 polymers are also now thought to be secreted attached to the epithelial surface of goblet cells in the small intestine and removed following secretion via a metalloprotease meprin β-mediated cleavage of the von Willebrand D2 domain of the N-terminus. It remains unclear whether MUC2 forms intermolecular dimers, trimers, or both, at the N-termini during polymerisation, with several articles supporting either trimer or dimer formation. The presence of a firm inner mucus layer in the small intestine is similarly unclear. Considering this recent research, this review proposes an update to the previous model of MUC2 polymerisation and secretion, considers conflicting theories and data, and highlights the importance of this research to the understanding of MUC2 mucus layers in health and disease.
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Affiliation(s)
- Kyle J. Stanforth
- Aelius Biotech, The Medical School, Framlington Place, Newcastle-upon-Tyne NE2 4HH, UK; (P.I.C.); (M.D.W.); (B.A.); (N.A.R.)
| | - Maria I. Zakhour
- Biosciences Institute, Newcastle University Biosciences Institute, Catherine Cookson Building, Framlington Place, Newcastle-upon-Tyne NE2 4HH, UK; (M.I.Z.); (J.P.P.)
| | - Peter I. Chater
- Aelius Biotech, The Medical School, Framlington Place, Newcastle-upon-Tyne NE2 4HH, UK; (P.I.C.); (M.D.W.); (B.A.); (N.A.R.)
| | - Matthew D. Wilcox
- Aelius Biotech, The Medical School, Framlington Place, Newcastle-upon-Tyne NE2 4HH, UK; (P.I.C.); (M.D.W.); (B.A.); (N.A.R.)
| | - Beth Adamson
- Aelius Biotech, The Medical School, Framlington Place, Newcastle-upon-Tyne NE2 4HH, UK; (P.I.C.); (M.D.W.); (B.A.); (N.A.R.)
| | - Niamh A. Robson
- Aelius Biotech, The Medical School, Framlington Place, Newcastle-upon-Tyne NE2 4HH, UK; (P.I.C.); (M.D.W.); (B.A.); (N.A.R.)
| | - Jeffrey P. Pearson
- Biosciences Institute, Newcastle University Biosciences Institute, Catherine Cookson Building, Framlington Place, Newcastle-upon-Tyne NE2 4HH, UK; (M.I.Z.); (J.P.P.)
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7
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Harris ES, McIntire HJ, Mazur M, Schulz-Hildebrandt H, Leung HM, Tearney GJ, Krick S, Rowe SM, Barnes JW. Reduced Sialylation of Airway Mucin Impairs Mucus Transport by Altering the Biophysical Properties of Mucin. RESEARCH SQUARE 2024:rs.3.rs-4421613. [PMID: 38853971 PMCID: PMC11160914 DOI: 10.21203/rs.3.rs-4421613/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2024]
Abstract
Mucus stasis is a pathologic hallmark of muco-obstructive diseases, including cystic fibrosis (CF). Mucins, the principal component of mucus, are extensively modified with hydroxyl (O)-linked glycans, which are largely terminated by sialic acid. Sialic acid is a negatively charged monosaccharide and contributes to the biochemical/biophysical properties of mucins. Reports suggest that mucin sialylation may be altered in CF; however, the consequences of reduced sialylation on mucus clearance have not been fully determined. Here, we investigated the consequences of reduced sialylation on the charge state and conformation of the most prominent airway mucin, MUC5B, and defined the functional consequences of reduced sialylation on mucociliary transport (MCT). Reduced sialylation contributed to a lower charged MUC5B form and decreased polymer expansion. The inhibition of total mucin sialylation de novo impaired MCT in primary human bronchial epithelial cells and rat airways, and specific α-2,3 sialylation blockade was sufficient to recapitulate these findings. Finally, we show that ST3 beta-galactoside alpha-2,3-sialyltransferase (ST3Gal1) expression is downregulated in CF and partially restored by correcting CFTR via Elexacaftor/Tezacaftor/Ivacaftor treatment. Overall, this study demonstrates the importance of mucin sialylation in mucus clearance and identifies decreased sialylation by ST3Gal1 as a possible therapeutic target in CF and potentially other muco-obstructive diseases.
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Affiliation(s)
- Elex S Harris
- Gregory Fleming James Cystic Fibrosis Research Center, Univ. of Alabama at Birmingham, Birmingham, AL, USA
| | - Hannah J McIntire
- Gregory Fleming James Cystic Fibrosis Research Center, Univ. of Alabama at Birmingham, Birmingham, AL, USA
| | - Marina Mazur
- Gregory Fleming James Cystic Fibrosis Research Center, Univ. of Alabama at Birmingham, Birmingham, AL, USA
| | | | | | | | - Stefanie Krick
- Gregory Fleming James Cystic Fibrosis Research Center, Univ. of Alabama at Birmingham, Birmingham, AL, USA
| | - Steven M Rowe
- Gregory Fleming James Cystic Fibrosis Research Center, Univ. of Alabama at Birmingham, Birmingham, AL, USA
| | - Jarrod W Barnes
- Gregory Fleming James Cystic Fibrosis Research Center, Univ. of Alabama at Birmingham, Birmingham, AL, USA
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8
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Kovac A, Goss GG. Cellular mechanisms of ion and acid-base regulation in teleost gill ionocytes. J Comp Physiol B 2024:10.1007/s00360-024-01560-6. [PMID: 38761226 DOI: 10.1007/s00360-024-01560-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2024] [Revised: 04/16/2024] [Accepted: 04/27/2024] [Indexed: 05/20/2024]
Abstract
The mechanism(s) of sodium, chloride and pH regulation in teleost fishes has been the subject of intense interest for researchers over the past 100 years. The primary organ responsible for ionoregulatory homeostasis is the gill, and more specifically, gill ionocytes. Building on the theoretical and experimental research of the past, recent advances in molecular and cellular techniques in the past two decades have allowed for substantial advances in our understanding of mechanisms involved. With an increased diversity of teleost species and environmental conditions being investigated, it has become apparent that there are multiple strategies and mechanisms employed to achieve ion and acid-base homeostasis. This review will cover the historical developments in our understanding of the teleost fish gill, highlight some of the recent advances and conflicting information in our understanding of ionocyte function, and serve to identify areas that require further investigation to improve our understanding of complex cellular and molecular machineries involved in iono- and acid-base regulation.
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Affiliation(s)
- Anthony Kovac
- Department of Biological Sciences, University of Alberta, Edmonton, AB, T6G 2E9, Canada
| | - Greg G Goss
- Department of Biological Sciences, University of Alberta, Edmonton, AB, T6G 2E9, Canada.
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9
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Sackville MA, Gillis JA, Brauner CJ. The origins of gas exchange and ion regulation in fish gills: evidence from structure and function. J Comp Physiol B 2024:10.1007/s00360-024-01545-5. [PMID: 38530435 DOI: 10.1007/s00360-024-01545-5] [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: 12/18/2023] [Revised: 01/15/2024] [Accepted: 02/12/2024] [Indexed: 03/28/2024]
Abstract
Gill function in gas exchange and ion regulation has played key roles in the evolution of fishes. In this review, we summarize data from the fields of palaeontology, developmental biology and comparative physiology for when and how the gills first acquired these functions. Data from across disciplines strongly supports a stem vertebrate origin for gas exchange structures and function at the gills with the emergence of larger, more active fishes. However, the recent discovery of putative ionocytes in extant cephalochordates and hemichordates suggests that ion regulation at gills might have originated much earlier than gas exchange, perhaps in the ciliated pharyngeal arches in the last common ancestor of deuterostomes. We hypothesize that the ancestral form of ion regulation served a filter-feeding function in the ciliated pharyngeal arches, and was later coopted in vertebrates to regulate extracellular ion and acid-base balance. We propose that future research should explore ionocyte homology and function across extant deuterostomes to test this hypothesis and others in order to determine the ancestral origins of ion regulation in fish gills.
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Affiliation(s)
| | - J Andrew Gillis
- Bay Paul Centre, Marine Biological Laboratory, Woods Hole, MA, USA
| | - Colin J Brauner
- Department of Zoology, University of British Columbia, Vancouver, BC, Canada
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10
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Kelly S, Genevskiy V, Björklund S, Gonzalez-Martinez JF, Poeschke L, Schröder M, Nilius G, Tatkov S, Kocherbitov V. Water Sorption and Structural Properties of Human Airway Mucus in Health and Muco-Obstructive Diseases. Biomacromolecules 2024; 25:1578-1591. [PMID: 38333985 PMCID: PMC10934264 DOI: 10.1021/acs.biomac.3c01170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2023] [Revised: 01/25/2024] [Accepted: 01/25/2024] [Indexed: 02/10/2024]
Abstract
Muco-obstructive diseases change airway mucus properties, impairing mucociliary transport and increasing the likelihood of infections. To investigate the sorption properties and nanostructures of mucus in health and disease, we investigated mucus samples from patients and cell cultures (cc) from healthy, chronic obstructive pulmonary disease (COPD), and cystic fibrosis (CF) airways. Atomic force microscopy (AFM) revealed mucin monomers with typical barbell structures, where the globule to spacer volume ratio was the highest for CF mucin. Accordingly, synchrotron small-angle X-ray scattering (SAXS) revealed more pronounced scattering from CF mucin globules and suggested shorter carbohydrate side chains in CF mucin and longer side chains in COPD mucin. Quartz crystal microbalance with dissipation (QCM-D) analysis presented water sorption isotherms of the three types of human airway mucus, where, at high relative humidity, COPD mucus had the highest water content compared to cc-CF and healthy airway mucus (HAM). The higher hydration of the COPD mucus is consistent with the observation of longer side chains of the COPD mucins. At low humidity, no dehydration-induced glass transition was observed in healthy and diseased mucus, suggesting mucus remained in a rubbery state. However, in dialyzed cc-HAM, a sorption-desorption hysteresis (typically observed in the glassy state) appeared, suggesting that small molecules present in mucus suppress the glass transition.
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Affiliation(s)
- Susyn
J. Kelly
- Fisher
& Paykel Healthcare Ltd., 15 Maurice Paykel Place, East Tamaki, Auckland NZ-2013, New Zealand
- Department
of Clinical Sciences, Ross University of
Veterinary Medicine, Basseterre KN-0101, Saint
Kitts and Nevis
| | - Vladislav Genevskiy
- Biomedical
Science, Faculty of Health and Society, Malmö University, Malmö SE-20506, Sweden
- Biofilms
Research Center for Biointerfaces, Faculty of Health and Society, Malmö University, Malmö SE-20506, Sweden
| | - Sebastian Björklund
- Biomedical
Science, Faculty of Health and Society, Malmö University, Malmö SE-20506, Sweden
- Biofilms
Research Center for Biointerfaces, Faculty of Health and Society, Malmö University, Malmö SE-20506, Sweden
| | | | - Lara Poeschke
- Evang. Kliniken
Essen-Mitte GmbH, Essen DE-45136, Germany
| | - Maik Schröder
- Evang. Kliniken
Essen-Mitte GmbH, Essen DE-45136, Germany
| | - Georg Nilius
- Evang. Kliniken
Essen-Mitte GmbH, Essen DE-45136, Germany
- Universität
Witten/Herdecke, Witten DE-58455, Germany
| | - Stanislav Tatkov
- Fisher
& Paykel Healthcare Ltd., 15 Maurice Paykel Place, East Tamaki, Auckland NZ-2013, New Zealand
| | - Vitaly Kocherbitov
- Biomedical
Science, Faculty of Health and Society, Malmö University, Malmö SE-20506, Sweden
- Biofilms
Research Center for Biointerfaces, Faculty of Health and Society, Malmö University, Malmö SE-20506, Sweden
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Bruorton M, Donnelley M, Goddard T, O'Connor A, Parsons D, Phillips J, Carson-Chahhoud K, Tai A. Pilot study of paediatric regional lung function assessment via X-ray velocimetry (XV) imaging in children with normal lungs and in children with cystic fibrosis. BMJ Open 2024; 14:e080034. [PMID: 38316593 PMCID: PMC10860032 DOI: 10.1136/bmjopen-2023-080034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Accepted: 01/07/2024] [Indexed: 02/07/2024] Open
Abstract
INTRODUCTION Cystic fibrosis (CF) is a life-limiting autosomal recessive genetic condition. It is caused by mutations in the gene that encodes for a chloride and bicarbonate conducting transmembrane channel. X-ray velocimetry (XV) is a novel form of X-ray imaging that can generate lung ventilation data through the breathing cycle. XV technology has been validated in multiple animal models, including the β-ENaC mouse model of CF lung disease. It has since been assessed in early-phase clinical trials in adult human subjects; however, there is a paucity of data in the paediatric cohort, including in CF. The aim of this pilot study was to investigate the feasibility of performing a single-centre cohort study in paediatric patients with CF and in those with normal lungs to demonstrate the appropriateness of proceeding with further studies of XV in these cohorts. METHODS AND ANALYSIS This is a cross-sectional, single-centre, pilot study. It will recruit children aged 3-18 years to have XV lung imaging performed, as well as paired pulmonary function testing. The study will aim to recruit 20 children without CF with normal lungs and 20 children with CF. The primary outcome will be the feasibility of recruiting children and performing XV testing. Secondary outcomes will include comparisons between XV and current assessments of pulmonary function and structure. ETHICS AND DISSEMINATION This project has ethical approval granted by The Women's and Children's Hospital Human Research Ethics Committee (HREC ID 2021/HRE00396). Findings will be disseminated through peer-reviewed publication and conferences. TRIAL REGISTRATION NUMBER ACTRN12623000109606.
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Affiliation(s)
- Matthew Bruorton
- Adelaide Medical School and The Robinson Research Institute, The University of Adelaide, Adelaide, South Australia, Australia
- Respiratory and Sleep Department, Women's and Children's Health Network, North Adelaide, South Australia, Australia
| | - Martin Donnelley
- Adelaide Medical School and The Robinson Research Institute, The University of Adelaide, Adelaide, South Australia, Australia
| | - Thomas Goddard
- Adelaide Medical School and The Robinson Research Institute, The University of Adelaide, Adelaide, South Australia, Australia
- Respiratory and Sleep Department, Women's and Children's Health Network, North Adelaide, South Australia, Australia
| | - Antonia O'Connor
- Sleep Department, Sydney Children's Hospitals Network, Westmead, New South Wales, Australia
- University of New South Wales, Sydney, Sydney, Australia
| | - David Parsons
- Adelaide Medical School and The Robinson Research Institute, The University of Adelaide, Adelaide, South Australia, Australia
- Respiratory and Sleep Department, Women's and Children's Health Network, North Adelaide, South Australia, Australia
| | - Jessica Phillips
- Adelaide Medical School and The Robinson Research Institute, The University of Adelaide, Adelaide, South Australia, Australia
- Respiratory and Sleep Department, Women's and Children's Health Network, North Adelaide, South Australia, Australia
| | - Kristin Carson-Chahhoud
- Adelaide Medical School and The Robinson Research Institute, The University of Adelaide, Adelaide, South Australia, Australia
- Respiratory and Sleep Department, Women's and Children's Health Network, North Adelaide, South Australia, Australia
| | - Andrew Tai
- Adelaide Medical School and The Robinson Research Institute, The University of Adelaide, Adelaide, South Australia, Australia
- Respiratory and Sleep Department, Women's and Children's Health Network, North Adelaide, South Australia, Australia
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Abrami M, Biasin A, Tescione F, Tierno D, Dapas B, Carbone A, Grassi G, Conese M, Di Gioia S, Larobina D, Grassi M. Mucus Structure, Viscoelastic Properties, and Composition in Chronic Respiratory Diseases. Int J Mol Sci 2024; 25:1933. [PMID: 38339210 PMCID: PMC10856136 DOI: 10.3390/ijms25031933] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2023] [Revised: 01/25/2024] [Accepted: 01/31/2024] [Indexed: 02/12/2024] Open
Abstract
The respiratory mucus, a viscoelastic gel, effectuates a primary line of the airway defense when operated by the mucociliary clearance. In chronic respiratory diseases (CRDs), such as asthma, chronic obstructive pulmonary disease (COPD), and cystic fibrosis (CF), the mucus is overproduced and its solid content augments, changing its structure and viscoelastic properties and determining a derangement of essential defense mechanisms against opportunistic microbial (virus and bacteria) pathogens. This ensues in damaging of the airways, leading to a vicious cycle of obstruction and infection responsible for the harsh clinical evolution of these CRDs. Here, we review the essential features of normal and pathological mucus (i.e., sputum in CF, COPD, and asthma), i.e., mucin content, structure (mesh size), micro/macro-rheology, pH, and osmotic pressure, ending with the awareness that sputum biomarkers (mucins, inflammatory proteins and peptides, and metabolites) might serve to indicate acute exacerbation and response to therapies. There are some indications that old and novel treatments may change the structure, viscoelastic properties, and biomarker content of sputum; however, a wealth of work is still needed to embrace these measures as correlates of disease severity in association with (or even as substitutes of) pulmonary functional tests.
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Affiliation(s)
- Michela Abrami
- Department of Engineering and Architecture, University of Trieste, Via Valerio 6/A, I-34127 Trieste, Italy; (M.A.); (A.B.); (M.G.)
| | - Alice Biasin
- Department of Engineering and Architecture, University of Trieste, Via Valerio 6/A, I-34127 Trieste, Italy; (M.A.); (A.B.); (M.G.)
| | - Fabiana Tescione
- Institute of Polymers, Composites and Biomaterials, National Research Council of Italy, P.le E. Fermi 1, I-80055 Portici, Italy; (F.T.); (D.L.)
| | - Domenico Tierno
- Clinical Department of Medical, Surgical and Health Sciences, Cattinara University Hospital, University of Trieste, Strada di Fiume 447, I-34149 Trieste, Italy; (D.T.); (G.G.)
| | - Barbara Dapas
- Department of Chemical and Pharmaceutical Sciences, University of Trieste, Via L. Giorgieri 1, I-34127 Trieste, Italy;
| | - Annalucia Carbone
- Department of Clinical and Experimental Medicine, University of Foggia, Via Napoli 121, I-71122 Foggia, Italy; (A.C.); (S.D.G.)
| | - Gabriele Grassi
- Clinical Department of Medical, Surgical and Health Sciences, Cattinara University Hospital, University of Trieste, Strada di Fiume 447, I-34149 Trieste, Italy; (D.T.); (G.G.)
| | - Massimo Conese
- Department of Clinical and Experimental Medicine, University of Foggia, Via Napoli 121, I-71122 Foggia, Italy; (A.C.); (S.D.G.)
| | - Sante Di Gioia
- Department of Clinical and Experimental Medicine, University of Foggia, Via Napoli 121, I-71122 Foggia, Italy; (A.C.); (S.D.G.)
| | - Domenico Larobina
- Institute of Polymers, Composites and Biomaterials, National Research Council of Italy, P.le E. Fermi 1, I-80055 Portici, Italy; (F.T.); (D.L.)
| | - Mario Grassi
- Department of Engineering and Architecture, University of Trieste, Via Valerio 6/A, I-34127 Trieste, Italy; (M.A.); (A.B.); (M.G.)
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13
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Zajac M, Lepissier A, Dréano E, Chevalier B, Hatton A, Kelly-Aubert M, Guidone D, Planelles G, Edelman A, Girodon E, Hinzpeter A, Crambert G, Pranke I, Galietta LJV, Sermet-Gaudelus I. Putting bicarbonate on the spot: pharmacological insights for CFTR correction in the airway epithelium. Front Pharmacol 2023; 14:1293578. [PMID: 38149052 PMCID: PMC10750368 DOI: 10.3389/fphar.2023.1293578] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Accepted: 11/17/2023] [Indexed: 12/28/2023] Open
Abstract
Introduction: Cystic fibrosis (CF) is caused by defective Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) proteins. CFTR controls chloride (Cl-) and bicarbonate (HCO3 -) transport into the Airway Surface Liquid (ASL). We investigated the impact of F508del-CFTR correction on HCO3 - secretion by studying transepithelial HCO3 - fluxes. Methods: HCO3 - secretion was measured by pH-stat technique in primary human respiratory epithelial cells from healthy subjects (WT) and people with CF (pwCF) carrying at least one F508del variant. Its changes after CFTR modulation by the triple combination VX445/661/770 and in the context of TNF-α+IL-17 induced inflammation were correlated to ASL pH and transcriptional levels of CFTR and other HCO3 - transporters of airway epithelia such as SLC26A4 (Pendrin), SLC26A9 and NBCe1. Results: CFTR-mediated HCO3 - secretion was not detected in F508del primary human respiratory epithelial cells. It was rescued up to ∼ 80% of the WT level by VX-445/661/770. In contrast, TNF-α+IL-17 normalized transepithelial HCO3 - transport and increased ASL pH. This was related to an increase in SLC26A4 and CFTR transcript levels. VX-445/661/770 induced an increase in pH only in the context of inflammation. Effects on HCO3 - transport were not different between F508del homozygous and F508del compound heterozygous CF airway epithelia. Conclusion: Our studies show that correction of F508del-CFTR HCO3 - is not sufficient to buffer acidic ASL and inflammation is a key regulator of HCO3 - secretion in CF airways. Prediction of the response to CFTR modulators by theratyping should take into account airway inflammation.
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Affiliation(s)
- Miroslaw Zajac
- INSERM U1151, Institut Necker Enfants Malades, Paris, France
- Université de Paris-Cité, Paris, France
- Centre de Référence Maladie Rare Pour La Mucoviscidose et Maladies de CFTR, Hôpital Necker Enfants Malades, Assistance Publique Hôpitaux de Paris, Paris, France
- Department of Physics and Biophysics, Institute of Biology, Warsaw University of Life Sciences, Warsaw, Poland
| | - Agathe Lepissier
- INSERM U1151, Institut Necker Enfants Malades, Paris, France
- Université de Paris-Cité, Paris, France
- Centre de Référence Maladie Rare Pour La Mucoviscidose et Maladies de CFTR, Hôpital Necker Enfants Malades, Assistance Publique Hôpitaux de Paris, Paris, France
| | - Elise Dréano
- INSERM U1151, Institut Necker Enfants Malades, Paris, France
- Université de Paris-Cité, Paris, France
- Centre de Référence Maladie Rare Pour La Mucoviscidose et Maladies de CFTR, Hôpital Necker Enfants Malades, Assistance Publique Hôpitaux de Paris, Paris, France
| | - Benoit Chevalier
- INSERM U1151, Institut Necker Enfants Malades, Paris, France
- Université de Paris-Cité, Paris, France
- Centre de Référence Maladie Rare Pour La Mucoviscidose et Maladies de CFTR, Hôpital Necker Enfants Malades, Assistance Publique Hôpitaux de Paris, Paris, France
| | - Aurélie Hatton
- INSERM U1151, Institut Necker Enfants Malades, Paris, France
- Université de Paris-Cité, Paris, France
- Centre de Référence Maladie Rare Pour La Mucoviscidose et Maladies de CFTR, Hôpital Necker Enfants Malades, Assistance Publique Hôpitaux de Paris, Paris, France
| | - Mairead Kelly-Aubert
- INSERM U1151, Institut Necker Enfants Malades, Paris, France
- Université de Paris-Cité, Paris, France
- Centre de Référence Maladie Rare Pour La Mucoviscidose et Maladies de CFTR, Hôpital Necker Enfants Malades, Assistance Publique Hôpitaux de Paris, Paris, France
| | - Daniela Guidone
- Telethon Institute of Genetics and Medicine, Pozzuoli, Italy
| | | | - Aleksander Edelman
- INSERM U1151, Institut Necker Enfants Malades, Paris, France
- Université de Paris-Cité, Paris, France
- Centre de Référence Maladie Rare Pour La Mucoviscidose et Maladies de CFTR, Hôpital Necker Enfants Malades, Assistance Publique Hôpitaux de Paris, Paris, France
| | - Emmanuelle Girodon
- Université de Paris-Cité, Paris, France
- Service de Médecine Génomique des Maladies de Système et d’Organe, Hôpital Cochin, Paris, France
| | - Alexandre Hinzpeter
- INSERM U1151, Institut Necker Enfants Malades, Paris, France
- Université de Paris-Cité, Paris, France
- Centre de Référence Maladie Rare Pour La Mucoviscidose et Maladies de CFTR, Hôpital Necker Enfants Malades, Assistance Publique Hôpitaux de Paris, Paris, France
| | - Gilles Crambert
- U1138/CNRS ERL 8228, Centre de Recherche des Cordeliers, Paris, France
| | - Iwona Pranke
- INSERM U1151, Institut Necker Enfants Malades, Paris, France
- Université de Paris-Cité, Paris, France
- Centre de Référence Maladie Rare Pour La Mucoviscidose et Maladies de CFTR, Hôpital Necker Enfants Malades, Assistance Publique Hôpitaux de Paris, Paris, France
| | | | - Isabelle Sermet-Gaudelus
- INSERM U1151, Institut Necker Enfants Malades, Paris, France
- Université de Paris-Cité, Paris, France
- Centre de Référence Maladie Rare Pour La Mucoviscidose et Maladies de CFTR, Hôpital Necker Enfants Malades, Assistance Publique Hôpitaux de Paris, Paris, France
- European Reference Network for Rare Diseases, Frankfurt, Belgium
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14
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Habibullah MM. The role of CFTR channel in female infertility. HUM FERTIL 2023; 26:1228-1237. [PMID: 36576330 DOI: 10.1080/14647273.2022.2161427] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2021] [Accepted: 03/06/2022] [Indexed: 12/29/2022]
Abstract
The cystic fibrosis transmembrane conductance regulator (CFTR) is a cAMP-activated trans-membrane ATP gated anion channel present in most epithelia, which transports chloride and bicarbonate ions across the apical membrane. Mutations in the CFTR protein are known to result in defective expression or function, notably the inhibition of chloride and bicarbonate transport. This can result in cystic fibrosis (CF), a disorder characterised by thickness of the mucus lining of the epithelial cells of the alimentary and respiratory tracts, sweat ducts and reproductive organs. As a consequence, there is a reduction in fluid transport at the apical surface. While the most devastating effect of CF is mortality, about 98% of men with CF are infertile, consequent of early blockage of or failure to develop the mesonephrotic ducts as well as the vas deferens. The effect of CF of female fertility is less well-understood. This review highlights the genetics and pathophysiology as well as the mechanism of action of CF on female infertility.
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Affiliation(s)
- Mahmoud M Habibullah
- Department of Medical Laboratory Technology, Faculty of Applied Medical Sciences, Jazan University, Jazan, Saudi Arabia
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15
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Harris ES, Novak L, Fernandez-Petty CM, Lindgren NR, Baker SM, Birket SE, Rowe SM. SNSP113 (PAAG) improves mucociliary transport and lung pathology in the Scnn1b-Tg murine model of CF lung disease. J Cyst Fibros 2023; 22:1104-1112. [PMID: 37714777 PMCID: PMC10843010 DOI: 10.1016/j.jcf.2023.08.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Revised: 07/25/2023] [Accepted: 08/29/2023] [Indexed: 09/17/2023]
Abstract
BACKGROUND Mucus stasis, a hallmark of muco-obstructive disease, results from impaired mucociliary transport and leads to lung function decline and chronic infection. Although therapeutics that target mucus stasis in the airway, such as hypertonic saline or rhDNAse, show some therapeutic benefit, they do not address the underlying electrostatic defect apparent in mucins in CF and related conditions. We have previously shown poly (acetyl, arginyl) glucosamine (PAAG, developed as SNSP113), a soluble, cationic polymer, significantly improves mucociliary transport in a rat model of CF by normalizing the charge defects of CF mucin. Here, we report efficacy in the CFTR-sufficient, ENaC hyperactive, Scnn1b-Tg mouse model that develops airway muco-obstruction due to sodium hyperabsorption and airway dehydration. METHODS Scnn1b-Tg mice were treated with either 250 µg/mL SNSP113 or vehicle control (1.38% glycerol in PBS) via nebulization once daily for 7 days and then euthanized for analysis. Micro-Optical Coherence Tomography-based evaluation of excised mouse trachea was used to determine the effect on the functional microanatomy. Tissue analysis was performed by routine histopathology. RESULTS Nebulized treatment of SNSP113 significantly improved mucociliary transport in the airways of Scnn1b-Tg mice, without altering the airway surface or periciliary liquid layer. In addition, SNSP113 significantly reversed epithelial hypertrophy and goblet cell metaplasia. Finally, SNSP113 significantly ameliorated eosinophilic crystalline pneumonia and lung consolidation in addition to inflammatory macrophage influx in this model. CONCLUSION Overall, this study extends the efficacy of SNSP113 as a potential therapeutic to alleviate mucus stasis in muco-obstructive diseases in CF and potentially in related conditions.
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Affiliation(s)
- Elex S Harris
- Gregory Fleming James Cystic Fibrosis Research Center, Univ. of Alabama at Birmingham, Birmingham, AL, USA
| | - Lea Novak
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Courtney M Fernandez-Petty
- Gregory Fleming James Cystic Fibrosis Research Center, Univ. of Alabama at Birmingham, Birmingham, AL, USA
| | - Natalie R Lindgren
- Gregory Fleming James Cystic Fibrosis Research Center, Univ. of Alabama at Birmingham, Birmingham, AL, USA
| | | | - Susan E Birket
- Gregory Fleming James Cystic Fibrosis Research Center, Univ. of Alabama at Birmingham, Birmingham, AL, USA; Departments of Pediatrics, and Cell Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Steven M Rowe
- Gregory Fleming James Cystic Fibrosis Research Center, Univ. of Alabama at Birmingham, Birmingham, AL, USA; Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA; Departments of Pediatrics, and Cell Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL, USA.
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16
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Graeber SY, Mall MA. The future of cystic fibrosis treatment: from disease mechanisms to novel therapeutic approaches. Lancet 2023; 402:1185-1198. [PMID: 37699417 DOI: 10.1016/s0140-6736(23)01608-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Revised: 07/23/2023] [Accepted: 07/31/2023] [Indexed: 09/14/2023]
Abstract
With the 2019 breakthrough in the development of highly effective modulator therapy providing unprecedented clinical benefits for over 90% of patients with cystic fibrosis who are genetically eligible for treatment, this rare disease has become a front runner of transformative molecular therapy. This success is based on fundamental research, which led to the identification of the disease-causing CFTR gene and our subsequent understanding of the disease mechanisms underlying the pathogenesis of cystic fibrosis, working together with a continuously evolving clinical research and drug development pipeline. In this Series paper, we focus on advances since 2018, and remaining knowledge gaps in our understanding of the molecular mechanisms of CFTR dysfunction in the airway epithelium and their links to mucus dysfunction, impaired host defences, airway infection, and chronic inflammation of the lungs of people with cystic fibrosis. We review progress in (and the remaining obstacles to) pharmacological approaches to rescue CFTR function, and novel strategies for improved symptomatic therapies for cystic fibrosis, including how these might be applicable to common lung diseases, such as bronchiectasis and chronic obstructive pulmonary disease. Finally, we discuss the promise of genetic therapies and gene editing approaches to restore CFTR function in the lungs of all patients with cystic fibrosis independent of their CFTR genotype, and the unprecedented opportunities to transform cystic fibrosis from a fatal disease to a treatable and potentially curable one.
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Affiliation(s)
- Simon Y Graeber
- Department of Pediatric Respiratory Medicine, Immunology and Critical Care Medicine, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany; Cystic Fibrosis Center, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany; German Center for Lung Research, associated partner site, Berlin, Germany; Berlin Institute of Health at Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Marcus A Mall
- Department of Pediatric Respiratory Medicine, Immunology and Critical Care Medicine, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany; Cystic Fibrosis Center, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany; German Center for Lung Research, associated partner site, Berlin, Germany; Berlin Institute of Health at Charité-Universitätsmedizin Berlin, Berlin, Germany.
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Dębczyński M, Gorrieri G, Mojsak D, Guida F, Zara F, Scudieri P. ATP12A Proton Pump as an Emerging Therapeutic Target in Cystic Fibrosis and Other Respiratory Diseases. Biomolecules 2023; 13:1455. [PMID: 37892136 PMCID: PMC10605105 DOI: 10.3390/biom13101455] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Revised: 09/15/2023] [Accepted: 09/25/2023] [Indexed: 10/29/2023] Open
Abstract
ATP12A encodes the catalytic subunit of the non-gastric proton pump, which is expressed in many epithelial tissues and mediates the secretion of protons in exchange for potassium ions. In the airways, ATP12A-dependent proton secretion contributes to complex mechanisms regulating the composition and properties of the fluid and mucus lining the respiratory epithelia, which are essential to maintain the airway host defense and the respiratory health. Increased expression and activity of ATP12A in combination with the loss of other balancing activities, such as the bicarbonate secretion mediated by CFTR, leads to excessive acidification of the airway surface liquid and mucus dysfunction, processes that play relevant roles in the pathogenesis of cystic fibrosis and other chronic inflammatory respiratory disorders. In this review, we summarize the findings dealing with ATP12A expression, function, and modulation in the airways, which led to the consideration of ATP12A as a potential therapeutic target for the treatment of cystic fibrosis and other airway diseases; we also highlight the current advances and gaps regarding the development of therapeutic strategies aimed at ATP12A inhibition.
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Affiliation(s)
- Michał Dębczyński
- 2nd Department of Lung Diseases and Tuberculosis, Medical University of Bialystok, 15-540 Bialystok, Poland; (M.D.); (D.M.)
| | - Giulia Gorrieri
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health (DiNOGMI), University of Genoa, 16132 Genoa, Italy; (G.G.); (F.G.); (F.Z.)
| | - Damian Mojsak
- 2nd Department of Lung Diseases and Tuberculosis, Medical University of Bialystok, 15-540 Bialystok, Poland; (M.D.); (D.M.)
| | - Floriana Guida
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health (DiNOGMI), University of Genoa, 16132 Genoa, Italy; (G.G.); (F.G.); (F.Z.)
| | - Federico Zara
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health (DiNOGMI), University of Genoa, 16132 Genoa, Italy; (G.G.); (F.G.); (F.Z.)
- Unit of Medical Genetics, IRCCS Istituto Giannina Gaslini, 16147 Genoa, Italy
| | - Paolo Scudieri
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health (DiNOGMI), University of Genoa, 16132 Genoa, Italy; (G.G.); (F.G.); (F.Z.)
- Unit of Medical Genetics, IRCCS Istituto Giannina Gaslini, 16147 Genoa, Italy
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18
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Salari A, Xiu R, Amiri M, Pallenberg ST, Schreiber R, Dittrich AM, Tümmler B, Kunzelmann K, Seidler U. The Anion Channel TMEM16a/Ano1 Modulates CFTR Activity, but Does Not Function as an Apical Anion Channel in Colonic Epithelium from Cystic Fibrosis Patients and Healthy Individuals. Int J Mol Sci 2023; 24:14214. [PMID: 37762516 PMCID: PMC10531629 DOI: 10.3390/ijms241814214] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Revised: 09/08/2023] [Accepted: 09/11/2023] [Indexed: 09/29/2023] Open
Abstract
Studies in human colonic cell lines and murine intestine suggest the presence of a Ca2+-activated anion channel, presumably TMEM16a. Is there a potential for fluid secretion in patients with severe cystic fibrosis transmembrane conductance regulator (CFTR) mutations by activating this alternative pathway? Two-dimensional nondifferentiated colonoid-myofibroblast cocultures resembling transit amplifying/progenitor (TA/PE) cells, as well as differentiated monolayer (DM) cultures resembling near-surface cells, were established from both healthy controls (HLs) and patients with severe functional defects in the CFTR gene (PwCF). F508del mutant and CFTR knockout (null) mice ileal and colonic mucosa was also studied. HL TA/PE monolayers displayed a robust short-circuit current response (ΔIeq) to UTP (100 µM), forskolin (Fsk, 10 µM) and carbachol (CCH, 100 µM), while ΔIeq was much smaller in differentiated monolayers. The selective TMEM16a inhibitor Ani9 (up to 30 µM) did not alter the response to luminal UTP, significantly decreased Fsk-induced ΔIeq, and significantly increased CCH-induced ΔIeq in HL TA/PE colonoid monolayers. The PwCF TA/PE and the PwCF differentiated monolayers displayed negligible agonist-induced ΔIeq, without a significant effect of Ani9. When TMEM16a was localized in intracellular structures, a staining in the apical membrane was not detected. TMEM16a is highly expressed in human colonoid monolayers resembling transit amplifying cells of the colonic cryptal neck zone, from both HL and PwCF. While it may play a role in modulating agonist-induced CFTR-mediated anion currents, it is not localized in the apical membrane, and it has no function as an apical anion channel in cystic fibrosis (CF) and healthy human colonic epithelium.
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Affiliation(s)
- Azam Salari
- Department of Gastroenterology, Hannover Medical School, 30625 Hannover, Germany; (A.S.); (R.X.); (M.A.)
| | - Renjie Xiu
- Department of Gastroenterology, Hannover Medical School, 30625 Hannover, Germany; (A.S.); (R.X.); (M.A.)
| | - Mahdi Amiri
- Department of Gastroenterology, Hannover Medical School, 30625 Hannover, Germany; (A.S.); (R.X.); (M.A.)
| | - Sophia Theres Pallenberg
- Department of Pediatric Pneumonology, Allergology and Neonatology, Hannover Medical School, 30625 Hannover, Germany (A.-M.D.)
| | - Rainer Schreiber
- Institute of Physiology, University of Regensburg, 93040 Regensburg, Germany; (R.S.); (K.K.)
| | - Anna-Maria Dittrich
- Department of Pediatric Pneumonology, Allergology and Neonatology, Hannover Medical School, 30625 Hannover, Germany (A.-M.D.)
| | - Burkhard Tümmler
- Department of Pediatric Pneumonology, Allergology and Neonatology, Hannover Medical School, 30625 Hannover, Germany (A.-M.D.)
| | - Karl Kunzelmann
- Institute of Physiology, University of Regensburg, 93040 Regensburg, Germany; (R.S.); (K.K.)
| | - Ursula Seidler
- Department of Gastroenterology, Hannover Medical School, 30625 Hannover, Germany; (A.S.); (R.X.); (M.A.)
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19
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Abstract
Cystic fibrosis (CF) is an autosomal recessive genetic disease caused by variants in the gene encoding for the cystic fibrosis transmembrane conductance regulator (CFTR) protein. CFTR dysfunction results in abnormal chloride and bicarbonate transport in epithelial cells, leading to a multiorgan disease dominated by respiratory and digestive manifestations. The respiratory disease, which is characterized by airway mucus plugging, chronic bacterial infection and progressive development of bronchiectasis, may lead to chronic respiratory failure, which is the main cause of premature death in people with CF. Over the past 50 years, major progress has been obtained by implementing multidisciplinary care, including nutritional support, airway clearance techniques and antibiotics in specialized CF centers. The past 10 years have further seen the progressive development of oral medications, called CFTR modulators, that partially restore ion transport and lead to a major improvement in clinical manifestations and lung function, presumably resulting in longer survival. Although an increasing proportion of people with CF are being treated with CFTR modulators, challenges remain regarding access to CFTR modulators due to their high cost, and their lack of marketing approval and/or effectiveness in people with rare CFTR variants. The anticipated increase in the number of adults with CF and their aging also challenge the current organization of CF care. The purpose of this review article is to describe current status and future perspective of CF disease and care.
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Affiliation(s)
- Isabelle Fajac
- Department of Respiratory Medicine and National Cystic Fibrosis Reference Centre, Cochin Hospital, Assistance Publique Hôpitaux de Paris, 27 rue du faubourg Saint-Jacques, 75014 Paris, France; Université Paris Cité, Inserm U1016, Institut Cochin, 24 rue du faubourg Saint-Jacques, 75014 Paris, France; ERN-LUNG, CF Core Network, Frankfurt, Germany.
| | - Pierre-Régis Burgel
- Department of Respiratory Medicine and National Cystic Fibrosis Reference Centre, Cochin Hospital, Assistance Publique Hôpitaux de Paris, 27 rue du faubourg Saint-Jacques, 75014 Paris, France; Université Paris Cité, Inserm U1016, Institut Cochin, 24 rue du faubourg Saint-Jacques, 75014 Paris, France; ERN-LUNG, CF Core Network, Frankfurt, Germany.
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20
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Pellielo G, Agyapong ED, Pinton P, Rimessi A. Control of mitochondrial functions by Pseudomonas aeruginosa in cystic fibrosis. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2023; 377:19-43. [PMID: 37268349 DOI: 10.1016/bs.ircmb.2023.03.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Cystic fibrosis (CF) is a genetic disease characterized by mutations of cystic fibrosis transmembrane conductance regulator (CFTR) gene, which lead to a dysfunctional chloride and bicarbonate channel. Abnormal mucus viscosity, persistent infections and hyperinflammation that preferentially affect the airways, referred to the pathogenesis of CF lung disease. It has largely demonstrated that Pseudomonas aeruginosa (P. aeruginosa) represents the most important pathogen that affect CF patients, leading to worsen inflammation by stimulating pro-inflammatory mediators release and tissue destruction. The conversion to mucoid phenotype and formation of biofilms, together with the increased frequency of mutations, are only few changes that characterize the P. aeruginosa's evolution during CF lung chronic infection. Recently, mitochondria received increasing attention due to their involvement in inflammatory-related diseases, including in CF. Alteration of mitochondrial homeostasis is sufficient to stimulate immune response. Exogenous or endogenous stimuli that perturb mitochondrial activity are used by cells, which, through the mitochondrial stress, potentiate immunity programs. Studies show the relationship between mitochondria and CF, supporting the idea that mitochondrial dysfunction endorses the exacerbation of inflammatory responses in CF lung. In particular, evidences suggest that mitochondria in CF airway cells are more susceptible to P. aeruginosa infection, with consequent detrimental effects that lead to amplify the inflammatory signals. This review discusses the evolution of P. aeruginosa in relationship with the pathogenesis of CF, a fundamental step to establish chronic infection in CF lung disease. Specifically, we focus on the role of P. aeruginosa in the exacerbation of inflammatory response, by triggering mitochondria in CF.
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Affiliation(s)
- Giulia Pellielo
- Department of Medical Sciences, Section of Experimental Medicine, Laboratory for Technologies of Advanced Therapies, University of Ferrara, Ferrara, Italy
| | - Esther Densu Agyapong
- Department of Medical Sciences, Section of Experimental Medicine, Laboratory for Technologies of Advanced Therapies, University of Ferrara, Ferrara, Italy
| | - Paolo Pinton
- Department of Medical Sciences, Section of Experimental Medicine, Laboratory for Technologies of Advanced Therapies, University of Ferrara, Ferrara, Italy; Center of research for innovative therapies in cystic fibrosis, University of Ferrara, Ferrara, Italy
| | - Alessandro Rimessi
- Department of Medical Sciences, Section of Experimental Medicine, Laboratory for Technologies of Advanced Therapies, University of Ferrara, Ferrara, Italy; Center of research for innovative therapies in cystic fibrosis, University of Ferrara, Ferrara, Italy.
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21
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Pangeni R, Meng T, Poudel S, Sharma D, Hutsell H, Ma J, Rubin BK, Longest W, Hindle M, Xu Q. Airway mucus in pulmonary diseases: Muco-adhesive and muco-penetrating particles to overcome the airway mucus barriers. Int J Pharm 2023; 634:122661. [PMID: 36736964 PMCID: PMC9975059 DOI: 10.1016/j.ijpharm.2023.122661] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Revised: 01/26/2023] [Accepted: 01/27/2023] [Indexed: 02/04/2023]
Abstract
Airway mucus is a complex viscoelastic gel that provides a defensive physical barrier and shields the airway epithelium by trapping inhaled foreign pathogens and facilitating their removal via mucociliary clearance (MCC). In patients with respiratory diseases, such as chronic obstructive pulmonary disease (COPD), cystic fibrosis (CF), non-CF bronchiectasis, and asthma, an increase in crosslinking and physical entanglement of mucin polymers as well as mucus dehydration often alters and typically reduces mucus mesh network pore size, which reduces neutrophil migration, decreases pathogen capture, sustains bacterial infection, and accelerates lung function decline. Conventional aerosol particles containing hydrophobic drugs are rapidly captured and removed by MCC. Therefore, it is critical to design aerosol delivery systems with the appropriate size and surface chemistry that can improve drug retention and absorption with the goal of increased efficacy. Biodegradable muco-adhesive particles (MAPs) and muco-penetrating particles (MPPs) have been engineered to achieve effective pulmonary delivery and extend drug residence time in the lungs. MAPs can be used to target mucus as they get trapped in airway mucus by steric obstruction and/or adhesion. MPPs avoid muco-adhesion and are designed to have a particle size smaller than the mucus network, enhancing lung retention of particles as well as transport to the respiratory epithelial layer and drug absorption. In this review, we aim to provide insight into the composition of airway mucus, rheological characteristics of airway mucus in healthy and diseased subjects, the most recent techniques to study the flow dynamics and particle diffusion in airway mucus (in particular, multiple particle tracking, MPT), and the advancements in engineering MPPs that have contributed to improved airway mucus penetration, lung distribution, and retention.
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Affiliation(s)
- Rudra Pangeni
- Department of Pharmaceutics, Virginia Commonwealth University, Richmond, VA, USA
| | - Tuo Meng
- Department of Pharmaceutics, Virginia Commonwealth University, Richmond, VA, USA
| | - Sagun Poudel
- Department of Pharmaceutics, Virginia Commonwealth University, Richmond, VA, USA
| | - Divya Sharma
- Department of Physiology and Biophysics, Virginia Commonwealth University, Richmond, VA, USA
| | - Hallie Hutsell
- Department of Pharmaceutics, Virginia Commonwealth University, Richmond, VA, USA
| | - Jonathan Ma
- Department of Pediatrics, Children's Hospital of Richmond, Richmond, VA, USA
| | - Bruce K Rubin
- Department of Physiology and Biophysics, Virginia Commonwealth University, Richmond, VA, USA; Department of Pediatrics, Children's Hospital of Richmond, Richmond, VA, USA
| | - Worth Longest
- Department of Pharmaceutics, Virginia Commonwealth University, Richmond, VA, USA; Department of Mechanical and Nuclear Engineering, Virginia Commonwealth University, Richmond, VA, USA
| | - Michael Hindle
- Department of Pharmaceutics, Virginia Commonwealth University, Richmond, VA, USA
| | - Qingguo Xu
- Department of Pharmaceutics, Virginia Commonwealth University, Richmond, VA, USA; Department of Ophthalmology, Massey Cancer Center, Center for Pharmaceutical Engineering, and Institute for Structural Biology, Drug Discovery & Development (ISB3D), Virginia Commonwealth University, Richmond, VA, USA.
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22
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Ehre C, Hansson GC, Thornton DJ, Ostedgaard LS. Mucus aberrant properties in CF: Insights from cells and animal models. J Cyst Fibros 2023; 22 Suppl 1:S23-S26. [PMID: 36117114 PMCID: PMC10018425 DOI: 10.1016/j.jcf.2022.08.019] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Revised: 08/26/2022] [Accepted: 08/30/2022] [Indexed: 10/14/2022]
Abstract
Cystic fibrosis (CF), an autosomal genetic disorder caused by the dysfunction of the cystic fibrosis transmembrane conductance regulator (CFTR) protein, is characterized by mucus accumulation in the lungs, the intestinal tract, and the pancreatic ducts. Mucins are high-molecular-weight glycoproteins that govern the biochemical and biophysical properties of mucus. In the CF lung, increased mucus viscoelasticity is associated with decreased mucociliary clearance and defects in host defense mechanisms. The link between defective ion channel and abnormal mucus properties has been investigated in studies involving cell and animal models. In this review article, we discuss recent progress toward understanding the different regions and cells that express CFTR in the airways and how mucus is produced and cleared from the lungs. In addition, we reflect on animal models that provided insights into the organization and the role of the mucin network and how mucus and antimicrobial activities act in concert to protect the lungs from invading pathogens.
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Affiliation(s)
- Camille Ehre
- University of North Carolina at Chapel Hill, Department of Pediatrics, Marsico Lung Institute, Chapel Hill, NC, USA
| | - Gunnar C Hansson
- Department Medical Biochemistry and Cell Biology, University of Gothenburg, Gothenburg, Sweden
| | - David J Thornton
- The Wellcome Trust Centre for Cell-Matrix Research, and The Lydia Becker Institute of Immunology and Inflammation, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
| | - Lynda S Ostedgaard
- Department of Internal Medicine, Carver College of Medicine, University of Iowa, Iowa City, IA, USA.
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23
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Rehman T, Karp PH, Thurman AL, Mather SE, Jain A, Cooney AL, Sinn PL, Pezzulo AA, Duffey ME, Welsh MJ. WNK Inhibition Increases Surface Liquid pH and Host Defense in Cystic Fibrosis Airway Epithelia. Am J Respir Cell Mol Biol 2022; 67:491-502. [PMID: 35849656 PMCID: PMC9564924 DOI: 10.1165/rcmb.2022-0172oc] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Accepted: 07/18/2022] [Indexed: 02/05/2023] Open
Abstract
In cystic fibrosis (CF), reduced HCO3- secretion acidifies the airway surface liquid (ASL), and the acidic pH disrupts host defenses. Thus, understanding the control of ASL pH (pHASL) in CF may help identify novel targets and facilitate therapeutic development. In diverse epithelia, the WNK (with-no-lysine [K]) kinases coordinate HCO3- and Cl- transport, but their functions in airway epithelia are poorly understood. Here, we tested the hypothesis that WNK kinases regulate CF pHASL. In primary cultures of differentiated human airway epithelia, inhibiting WNK kinases acutely increased both CF and non-CF pHASL. This response was HCO3- dependent and involved downstream SPAK/OSR1 (Ste20/SPS1-related proline-alanine-rich protein kinase/oxidative stress responsive 1 kinase). Importantly, WNK inhibition enhanced key host defenses otherwise impaired in CF. Human airway epithelia expressed two WNK isoforms in secretory cells and ionocytes, and knockdown of either WNK1 or WNK2 increased CF pHASL. WNK inhibition decreased Cl- secretion and the response to bumetanide, an NKCC1 (sodium-potassium-chloride cotransporter 1) inhibitor. Surprisingly, bumetanide alone or basolateral Cl- substitution also alkalinized CF pHASL. These data suggest that WNK kinases influence the balance between transepithelial Cl- versus HCO3- secretion. Moreover, reducing basolateral Cl- entry may increase HCO3- secretion and raise pHASL, thereby improving CF host defenses.
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Affiliation(s)
| | - Philip H. Karp
- Department of Internal Medicine and
- Howard Hughes Medical Institute, University of Iowa, Iowa City, Iowa; and
| | | | | | | | | | | | | | - Michael E. Duffey
- Department of Physiology and Biophysics, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, New York
| | - Michael J. Welsh
- Department of Internal Medicine and
- Department of Molecular Physiology and Biophysics, Roy J. and Lucille A. Carver College of Medicine, and
- Howard Hughes Medical Institute, University of Iowa, Iowa City, Iowa; and
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24
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Hill DB, Button B, Rubinstein M, Boucher RC. Physiology and pathophysiology of human airway mucus. Physiol Rev 2022; 102:1757-1836. [PMID: 35001665 PMCID: PMC9665957 DOI: 10.1152/physrev.00004.2021] [Citation(s) in RCA: 78] [Impact Index Per Article: 39.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Revised: 12/13/2021] [Accepted: 12/19/2021] [Indexed: 01/27/2023] Open
Abstract
The mucus clearance system is the dominant mechanical host defense system of the human lung. Mucus is cleared from the lung by cilia and airflow, including both two-phase gas-liquid pumping and cough-dependent mechanisms, and mucus transport rates are heavily dependent on mucus concentration. Importantly, mucus transport rates are accurately predicted by the gel-on-brush model of the mucociliary apparatus from the relative osmotic moduli of the mucus and periciliary-glycocalyceal (PCL-G) layers. The fluid available to hydrate mucus is generated by transepithelial fluid transport. Feedback interactions between mucus concentrations and cilia beating, via purinergic signaling, coordinate Na+ absorptive vs Cl- secretory rates to maintain mucus hydration in health. In disease, mucus becomes hyperconcentrated (dehydrated). Multiple mechanisms derange the ion transport pathways that normally hydrate mucus in muco-obstructive lung diseases, e.g., cystic fibrosis (CF), chronic obstructive pulmonary disease (COPD), non-CF bronchiectasis (NCFB), and primary ciliary dyskinesia (PCD). A key step in muco-obstructive disease pathogenesis is the osmotic compression of the mucus layer onto the airway surface with the formation of adherent mucus plaques and plugs, particularly in distal airways. Mucus plaques create locally hypoxic conditions and produce airflow obstruction, inflammation, infection, and, ultimately, airway wall damage. Therapies to clear adherent mucus with hydrating and mucolytic agents are rational, and strategies to develop these agents are reviewed.
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Affiliation(s)
- David B Hill
- Marsico Lung Institute, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
- Joint Department of Biomedical Engineering, The University of North Carolina and North Carolina State University, Chapel Hill, North Carolina
| | - Brian Button
- Marsico Lung Institute, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Michael Rubinstein
- Marsico Lung Institute, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
- Department of Mechanical Engineering and Materials Science, Biomedical Engineering, Physics, and Chemistry, Duke University, Durham, North Carolina
| | - Richard C Boucher
- Marsico Lung Institute, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
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25
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Dolan B, Ermund A, Martinez-Abad B, Johansson ME, Hansson GC. Clearance of small intestinal crypts involves goblet cell mucus secretion by intracellular granule rupture and enterocyte ion transport. Sci Signal 2022; 15:eabl5848. [PMID: 36126118 PMCID: PMC9749883 DOI: 10.1126/scisignal.abl5848] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Goblet cells in the small intestinal crypts contain large numbers of mucin granules that are rapidly discharged to clean bacteria from the crypt. Because acetylcholine released by neuronal and nonneuronal cells controls many aspects of intestinal epithelial function, we used tissue explants and organoids to investigate the response of the small intestinal crypt to cholinergic stimulation. The activation of muscarinic acetylcholine receptors initiated a coordinated and rapid emptying of crypt goblet cells that flushed the crypt contents into the intestinal lumen. Cholinergic stimulation induced an expansion of the granule contents followed by intracellular rupture of the mucin granules. The mucus expanded intracellularly before the rupture of the goblet cell apical membrane and continued to expand after its release into the crypt lumen. The goblet cells recovered from membrane rupture and replenished their stores of mucin granules. Mucus secretion from the goblet cells depended on Ca2+ signaling and the expansion of the mucus in the crypt depended on gap junctions and on ion and water transport by enterocytes adjacent to the goblet cells. This distinctive mode of mucus secretion, which we refer to as "expanding secretion," efficiently cleans the small intestine crypt through coordinated mucus, ion, and fluid secretion by goblet cells and enterocytes.
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Affiliation(s)
- Brendan Dolan
- Department of Medical Biochemistry and Cell Biology, University of
Gothenburg, 405 30 Gothenburg, Sweden
| | - Anna Ermund
- Department of Medical Biochemistry and Cell Biology, University of
Gothenburg, 405 30 Gothenburg, Sweden
| | - Beatriz Martinez-Abad
- Department of Medical Biochemistry and Cell Biology, University of
Gothenburg, 405 30 Gothenburg, Sweden
| | - Malin E.V. Johansson
- Department of Medical Biochemistry and Cell Biology, University of
Gothenburg, 405 30 Gothenburg, Sweden
| | - Gunnar C. Hansson
- Department of Medical Biochemistry and Cell Biology, University of
Gothenburg, 405 30 Gothenburg, Sweden
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26
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Mucins and CFTR: Their Close Relationship. Int J Mol Sci 2022; 23:ijms231810232. [PMID: 36142171 PMCID: PMC9499620 DOI: 10.3390/ijms231810232] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 08/27/2022] [Accepted: 08/29/2022] [Indexed: 01/27/2023] Open
Abstract
Mucociliary clearance is a critical defense mechanism for the lungs governed by regionally coordinated epithelial cellular activities, including mucin secretion, cilia beating, and transepithelial ion transport. Cystic fibrosis (CF), an autosomal genetic disorder caused by the dysfunction of the cystic fibrosis transmembrane conductance regulator (CFTR) channel, is characterized by failed mucociliary clearance due to abnormal mucus biophysical properties. In recent years, with the development of highly effective modulator therapies, the quality of life of a significant number of people living with CF has greatly improved; however, further understanding the cellular biology relevant to CFTR and airway mucus biochemical interactions are necessary to develop novel therapies aimed at restoring CFTR gene expression in the lungs. In this article, we discuss recent advances of transcriptome analysis at single-cell levels that revealed a heretofore unanticipated close relationship between secretory MUC5AC and MUC5B mucins and CFTR in the lungs. In addition, we review recent findings on airway mucus biochemical and biophysical properties, focusing on how mucin secretion and CFTR-mediated ion transport are integrated to maintain airway mucus homeostasis in health and how CFTR dysfunction and restoration of function affect mucus properties.
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27
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Bicarbonate Effects on Antibacterial Immunity and Mucus Glycobiology in the Cystic Fibrosis Lung: A Review With Selected Experimental Observations. INFECTIOUS MICROBES & DISEASES 2022; 4:103-110. [PMID: 36793929 PMCID: PMC9928163 DOI: 10.1097/im9.0000000000000101] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The primary defect in cystic fibrosis (CF) is abnormal chloride and bicarbonate transport in the cystic fibrosis transmembrane conductance regulator (CFTR) epithelial ion channel. The apical surface of the respiratory tract is lined by an airway surface liquid layer (ASL) composed of mucin comprising mainly MUC5A and MUC5B glycoproteins. ASL homeostasis depends on sodium bicarbonate secretion into the airways and secretion deficits alter mucus properties leading to airway obstruction, inflammation, and infections. Downstream effects of abnormal ion transport in the lungs include altered intrinsic immune defenses. We observed that neutrophils killed Pseudomonas aeruginosa more efficiently when it had been exposed to sodium bicarbonate, and formation of neutrophil extracellular traps (NETs) by neutrophils was augmented in the presence of increasing bicarbonate concentrations. Physiological levels of bicarbonate sensitized P. aeruginosa to the antimicrobial peptide cathelicidin LL-37, which is present in both lung ASL and in NETs. Sodium bicarbonate has various uses in clinical medicine and in the care of CF patients, and could be further explored as a therapeutic adjunct against Pseudomonas infections.
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28
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Current state of CFTR modulators for treatment of Cystic Fibrosis. Curr Opin Pharmacol 2022; 65:102239. [DOI: 10.1016/j.coph.2022.102239] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Revised: 03/31/2022] [Accepted: 04/13/2022] [Indexed: 12/23/2022]
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29
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Liu L, Yamamoto A, Yamaguchi M, Taniguchi I, Nomura N, Nakakuki M, Kozawa Y, Fukuyasu T, Higuchi M, Niwa E, Tamada T, Ishiguro H. Bicarbonate transport of airway surface epithelia in luminally perfused mice bronchioles. J Physiol Sci 2022; 72:4. [PMID: 35196991 PMCID: PMC10717372 DOI: 10.1186/s12576-022-00828-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2021] [Accepted: 02/14/2022] [Indexed: 01/06/2023]
Abstract
HCO3- secretion in distal airways is critical for airway mucosal defense. HCO3-/H+ transport across the apical membrane of airway surface epithelial cells was studied by measuring intracellular pH in luminally microperfused freshly dissected mice bronchioles. Functional studies demonstrated that CFTR, ENaC, Cl--HCO3- exchange, Na+-H+ exchange, and Na+-HCO3- cotransport are involved in apical HCO3-/H+ transport. RT-PCR of isolated bronchioles detected fragments from Cftr, α, β, γ subunits of ENaC, Ae2, Ae3, NBCe1, NBCe2, NBCn1, NDCBE, NBCn2, Nhe1, Nhe2, Nhe4, Nhe5, Slc26a4, Slc26a6, and Slc26a9. We assume that continuous decline of intracellular pH following alkaline load demonstrates time course of HCO3- secretion into the lumen which is perfused with a HCO3--free solution. Forskolin-stimulated HCO3- secretion was substantially inhibited by luminal application of CFTRinh-172 (5 μM), H2DIDS (200 μM), and amiloride (1 μM). In bronchioles from a cystic fibrosis mouse model, basal and acetylcholine-stimulated HCO3- secretion was substantially impaired, but forskolin transiently accelerated HCO3- secretion of which the magnitude was comparable to wild-type bronchioles. In conclusion, we have characterized apical HCO3-/H+ transport in native bronchioles. We have demonstrated that cAMP-mediated and Ca2+-mediated pathways are involved in HCO3- secretion and that apical HCO3- secretion is largely mediated by CFTR and H2DIDS-sensitive Cl--HCO3- exchanger, most likely Slc26a9. The impairment of HCO3- secretion in bronchioles from a cystic fibrosis mouse model may be related to the pathogenesis of early lung disease in cystic fibrosis.
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Affiliation(s)
- Libin Liu
- Department of Human Nutrition, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Akiko Yamamoto
- Department of Human Nutrition, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Makoto Yamaguchi
- Department of Human Nutrition, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Itsuka Taniguchi
- Department of Human Nutrition, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Nao Nomura
- Department of Human Nutrition, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Miyuki Nakakuki
- Department of Human Nutrition, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Yuka Kozawa
- Department of Human Nutrition, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Tomoya Fukuyasu
- Department of Human Nutrition, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Mayuko Higuchi
- Department of Human Nutrition, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Erina Niwa
- Department of Human Nutrition, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Tsutomu Tamada
- Department of Respiratory Medicine, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Hiroshi Ishiguro
- Department of Human Nutrition, Nagoya University Graduate School of Medicine, Nagoya, Japan.
- Research Center of Health, Physical Fitness, and Sports, Nagoya University, Furo-cho E5-2 (130), Chikusa-ku, Nagoya, 464-8601, Japan.
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30
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Badr A, Eltobgy M, Krause K, Hamilton K, Estfanous S, Daily KP, Abu Khweek A, Hegazi A, Anne MNK, Carafice C, Robledo-Avila F, Saqr Y, Zhang X, Bonfield TL, Gavrilin MA, Partida-Sanchez S, Seveau S, Cormet-Boyaka E, Amer AO. CFTR Modulators Restore Acidification of Autophago-Lysosomes and Bacterial Clearance in Cystic Fibrosis Macrophages. Front Cell Infect Microbiol 2022; 12:819554. [PMID: 35252032 PMCID: PMC8890004 DOI: 10.3389/fcimb.2022.819554] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2021] [Accepted: 01/19/2022] [Indexed: 12/17/2022] Open
Abstract
Cystic fibrosis (CF) human and mouse macrophages are defective in their ability to clear bacteria such as Burkholderia cenocepacia. The autophagy process in CF (F508del) macrophages is halted, and the underlying mechanism remains unclear. Furthermore, the role of CFTR in maintaining the acidification of endosomal and lysosomal compartments in CF cells has been a subject of debate. Using 3D reconstruction of z-stack confocal images, we show that CFTR is recruited to LC3-labeled autophagosomes harboring B. cenocepacia. Using several complementary approaches, we report that CF macrophages display defective lysosomal acidification and degradative function for cargos destined to autophagosomes, whereas non-autophagosomal cargos are effectively degraded within acidic compartments. Notably, treatment of CF macrophages with CFTR modulators (tezacaftor/ivacaftor) improved the autophagy flux, lysosomal acidification and function, and bacterial clearance. In addition, CFTR modulators improved CFTR function as demonstrated by patch-clamp. In conclusion, CFTR regulates the acidification of a specific subset of lysosomes that specifically fuse with autophagosomes. Therefore, our study describes a new biological location and function for CFTR in autophago-lysosomes and clarifies the long-standing discrepancies in the field.
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Affiliation(s)
- Asmaa Badr
- Department of Microbial Infection and Immunity, College of Medicine, The Ohio State University, Columbus, OH, United States
- Clinical Pathology Department, College of Medicine, Mansoura University, Mansoura, Egypt
| | - Mostafa Eltobgy
- Department of Microbial Infection and Immunity, College of Medicine, The Ohio State University, Columbus, OH, United States
| | - Kathrin Krause
- Department of Microbial Infection and Immunity, College of Medicine, The Ohio State University, Columbus, OH, United States
- Max Planck Unit for the Science of Pathogens, Berlin, Germany
| | - Kaitlin Hamilton
- Department of Microbial Infection and Immunity, College of Medicine, The Ohio State University, Columbus, OH, United States
| | - Shady Estfanous
- Department of Microbial Infection and Immunity, College of Medicine, The Ohio State University, Columbus, OH, United States
- Biochemistry and Molecular Biology Department, Faculty of Pharmacy, Helwan University, Cairo, Egypt
| | - Kylene P. Daily
- Department of Microbial Infection and Immunity, College of Medicine, The Ohio State University, Columbus, OH, United States
| | - Arwa Abu Khweek
- Department of Microbial Infection and Immunity, College of Medicine, The Ohio State University, Columbus, OH, United States
- Department of Biology and Biochemistry, Birzeit University, West Bank, Palestine
| | - Ahmad Hegazi
- Department of Microbial Infection and Immunity, College of Medicine, The Ohio State University, Columbus, OH, United States
| | - Midhun N. K. Anne
- Department of Microbial Infection and Immunity, College of Medicine, The Ohio State University, Columbus, OH, United States
| | - Cierra Carafice
- Department of Microbial Infection and Immunity, College of Medicine, The Ohio State University, Columbus, OH, United States
| | - Frank Robledo-Avila
- Center for Microbial Pathogenesis, Nationwide Children’s Hospital, Columbus, OH, United States
| | - Youssra Saqr
- Department of Microbial Infection and Immunity, College of Medicine, The Ohio State University, Columbus, OH, United States
| | - Xiaoli Zhang
- Center for Biostatistics, Ohio State University, Columbus, OH, United States
| | - Tracey L. Bonfield
- Department of Genetics and Genome Sciences, School of Medicine, Case Western Reserve University, Cleveland, OH, United States
| | - Mikhail A. Gavrilin
- Department of Genetics and Genome Sciences, School of Medicine, Case Western Reserve University, Columbus, OH, United States
| | | | - Stephanie Seveau
- Department of Microbial Infection and Immunity, College of Medicine, The Ohio State University, Columbus, OH, United States
| | - Estelle Cormet-Boyaka
- Department of Veterinary Biosciences, College of Veterinary Medicine, The Ohio State University, Columbus, OH, United States
| | - Amal O. Amer
- Department of Microbial Infection and Immunity, College of Medicine, The Ohio State University, Columbus, OH, United States
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31
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Morrison CB, Shaffer KM, Araba KC, Markovetz MR, Wykoff JA, Quinney NL, Hao S, Delion MF, Flen AL, Morton LC, Liao J, Hill DB, Drumm ML, O’Neal WK, Kesimer M, Gentzsch M, Ehre C. Treatment of cystic fibrosis airway cells with CFTR modulators reverses aberrant mucus properties via hydration. Eur Respir J 2022; 59:13993003.00185-2021. [PMID: 34172469 PMCID: PMC8859811 DOI: 10.1183/13993003.00185-2021] [Citation(s) in RCA: 34] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Accepted: 06/11/2021] [Indexed: 02/05/2023]
Abstract
QUESTION Cystic fibrosis (CF) is characterised by the accumulation of viscous adherent mucus in the lungs. While several hypotheses invoke a direct relationship with cystic fibrosis transmembrane conductance regulator (CFTR) dysfunction (i.e. acidic airway surface liquid (ASL) pH, low bicarbonate (HCO3 -) concentration, airway dehydration), the dominant biochemical alteration of CF mucus remains unknown. MATERIALS/METHODS We characterised a novel cell line (CFTR-KO Calu3 cells) and the responses of human bronchial epithelial (HBE) cells from subjects with G551D or F508del mutations to ivacaftor and elexacaftor-tezacaftor-ivacaftor. A spectrum of assays such as short-circuit currents, quantitative PCR, ASL pH, Western blotting, light scattering/refractometry (size-exclusion chromatography with inline multi-angle light scattering), scanning electron microscopy, percentage solids and particle tracking were performed to determine the impact of CFTR function on mucus properties. RESULTS Loss of CFTR function in Calu3 cells resulted in ASL pH acidification and mucus hyperconcentration (dehydration). Modulation of CFTR in CF HBE cells did not affect ASL pH or mucin mRNA expression, but decreased mucus concentration, relaxed mucus network ultrastructure and improved mucus transport. In contrast with modulator-treated cells, a large fraction of airway mucins remained attached to naïve CF cells following short apical washes, as revealed by the use of reducing agents to remove residual mucus from the cell surfaces. Extended hydration, but not buffers alkalised with sodium hydroxide or HCO3 -, normalised mucus recovery to modulator-treated cell levels. CONCLUSION These results indicate that airway dehydration, not acidic pH and/or low [HCO3 -], is responsible for abnormal mucus properties in CF airways and CFTR modulation predominantly restores normal mucin entanglement.
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Affiliation(s)
- Cameron B. Morrison
- Marsico Lung Institute / CF Center, The University of North Carolina at Chapel Hill
| | - Kendall M. Shaffer
- Marsico Lung Institute / CF Center, The University of North Carolina at Chapel Hill
| | - Kenza C. Araba
- Marsico Lung Institute / CF Center, The University of North Carolina at Chapel Hill
| | - Matthew R. Markovetz
- Marsico Lung Institute / CF Center, The University of North Carolina at Chapel Hill
| | - Jason A. Wykoff
- Marsico Lung Institute / CF Center, The University of North Carolina at Chapel Hill
| | - Nancy L. Quinney
- Marsico Lung Institute / CF Center, The University of North Carolina at Chapel Hill
| | - Shuyu Hao
- Department of Cell Biology and Physiology, The University of North Carolina at Chapel Hill
| | - Martial F. Delion
- Marsico Lung Institute / CF Center, The University of North Carolina at Chapel Hill
| | - Alexis L. Flen
- Marsico Lung Institute / CF Center, The University of North Carolina at Chapel Hill
| | - Lisa C. Morton
- Marsico Lung Institute / CF Center, The University of North Carolina at Chapel Hill
| | - Jimmy Liao
- Marsico Lung Institute / CF Center, The University of North Carolina at Chapel Hill
| | - David B. Hill
- Marsico Lung Institute / CF Center, The University of North Carolina at Chapel Hill,Department of Physics and Astronomy, The University of North Carolina at Chapel Hill
| | - Mitchell L. Drumm
- Department of Genetics and Genome Sciences, Case Western Reserve University School of Medicine
| | - Wanda K. O’Neal
- Marsico Lung Institute / CF Center, The University of North Carolina at Chapel Hill
| | - Mehmet Kesimer
- Marsico Lung Institute / CF Center, The University of North Carolina at Chapel Hill
| | - Martina Gentzsch
- Marsico Lung Institute / CF Center, The University of North Carolina at Chapel Hill,Division of Pediatric Pulmonology, The University of North Carolina at Chapel Hill,Department of Cell Biology and Physiology, The University of North Carolina at Chapel Hill
| | - Camille Ehre
- Marsico Lung Institute / CF Center, The University of North Carolina at Chapel Hill,Division of Pediatric Pulmonology, The University of North Carolina at Chapel Hill,To whom correspondence should be addressed:
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32
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Wine JJ. How the sweat gland reveals levels of CFTR activity. J Cyst Fibros 2022; 21:396-406. [DOI: 10.1016/j.jcf.2022.02.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 02/05/2022] [Accepted: 02/05/2022] [Indexed: 10/19/2022]
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Garcia BA, McDaniel MS, Loughran AJ, Johns JD, Narayanaswamy V, Fernandez Petty C, Birket SE, Baker SM, Barnaby R, Stanton BA, Foote JB, Rowe SM, Swords WE. Poly (acetyl, arginyl) glucosamine disrupts Pseudomonas aeruginosa biofilms and enhances bacterial clearance in a rat lung infection model. MICROBIOLOGY (READING, ENGLAND) 2022; 168. [PMID: 35077346 PMCID: PMC8914243 DOI: 10.1099/mic.0.001121] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Pseudomonas aeruginosa is a common opportunistic pathogen that can cause chronic infections in multiple disease states, including respiratory infections in patients with cystic fibrosis (CF) and non-CF bronchiectasis. Like many opportunists, P. aeruginosa forms multicellular biofilm communities that are widely thought to be an important determinant of bacterial persistence and resistance to antimicrobials and host immune effectors during chronic/recurrent infections. Poly (acetyl, arginyl) glucosamine (PAAG) is a glycopolymer that has antimicrobial activity against a broad range of bacterial species, and also has mucolytic activity, which can normalize the rheological properties of cystic fibrosis mucus. In this study, we sought to evaluate the effect of PAAG on P. aeruginosa bacteria within biofilms in vitro, and in the context of experimental pulmonary infection in a rodent infection model. PAAG treatment caused significant bactericidal activity against P. aeruginosa biofilms, and a reduction in the total biomass of preformed P. aeruginosa biofilms on abiotic surfaces, as well as on the surface of immortalized cystic fibrosis human bronchial epithelial cells. Studies of membrane integrity indicated that PAAG causes changes to P. aeruginosa cell morphology and dysregulates membrane polarity. PAAG treatment reduced infection and consequent tissue inflammation in experimental P. aeruginosa rat infections. Based on these findings we conclude that PAAG represents a novel means to combat P. aeruginosa infection, and may warrant further evaluation as a therapeutic.
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Affiliation(s)
- Bryan A Garcia
- Department of Medicine, Division of Pulmonary, Critical Care, and Sleep Medicine, Medical University of South Carolina, Charleston, SC, USA.,Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA.,Division of Pulmonary, Allergy, and Critical Care Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Melissa S McDaniel
- Division of Pulmonary, Allergy, and Critical Care Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA.,Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Allister J Loughran
- Synedgen, Inc., Claremont, CA, USA.,St Jude Children's Research Hospital, Memphis, TN, USA
| | - J Dixon Johns
- Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA.,Division of Pulmonary, Allergy, and Critical Care Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | | | | | - Susan E Birket
- Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA.,Division of Pulmonary, Allergy, and Critical Care Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA.,Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham, Birmingham, Alabama, USA.,Department of Cell Developmental and Integrative Physiology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Shenda M Baker
- Synedgen, Inc., Claremont, CA, USA.,Synspira Therapeutics, Inc., Framingham, MA, USA
| | - Roxanna Barnaby
- Dartmouth Cystic Fibrosis Research Center, New Hanover, NH, USA
| | - Bruce A Stanton
- Dartmouth Cystic Fibrosis Research Center, New Hanover, NH, USA
| | - Jeremy B Foote
- Comparative Pathology Laboratory, at University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Steven M Rowe
- Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA.,Division of Pulmonary, Allergy, and Critical Care Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA.,Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham, Birmingham, Alabama, USA.,Department of Cell Developmental and Integrative Physiology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - W Edward Swords
- Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA.,Division of Pulmonary, Allergy, and Critical Care Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA.,Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham, Birmingham, Alabama, USA
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34
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Pseudomonas aeruginosa in the Cystic Fibrosis Lung. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2022; 1386:347-369. [DOI: 10.1007/978-3-031-08491-1_13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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35
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Pathophysiological role of ion channels and transporters in gastrointestinal mucosal diseases. Cell Mol Life Sci 2021; 78:8109-8125. [PMID: 34778915 PMCID: PMC8629801 DOI: 10.1007/s00018-021-04011-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 09/10/2021] [Accepted: 10/23/2021] [Indexed: 11/13/2022]
Abstract
The incidence of gastrointestinal (GI) mucosal diseases, including various types of gastritis, ulcers, inflammatory bowel disease and GI cancer, is increasing. Therefore, it is necessary to identify new therapeutic targets. Ion channels/transporters are located on cell membranes, and tight junctions (TJs) affect acid–base balance, the mucus layer, permeability, the microbiota and mucosal blood flow, which are essential for maintaining GI mucosal integrity. As ion channel/transporter dysfunction results in various GI mucosal diseases, this review focuses on understanding the contribution of ion channels/transporters to protecting the GI mucosal barrier and the relationship between GI mucosal disease and ion channels/transporters, including Cl−/HCO3− exchangers, Cl− channels, aquaporins, Na+/H+ exchangers, and K+ channels. Here, we provide novel prospects for the treatment of GI mucosal diseases.
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36
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Multi-Omics Study of Keystone Species in a Cystic Fibrosis Microbiome. Int J Mol Sci 2021; 22:ijms222112050. [PMID: 34769481 PMCID: PMC8584531 DOI: 10.3390/ijms222112050] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Revised: 10/28/2021] [Accepted: 11/02/2021] [Indexed: 12/23/2022] Open
Abstract
Ecological networking and in vitro studies predict that anaerobic, mucus-degrading bacteria are keystone species in cystic fibrosis (CF) microbiomes. The metabolic byproducts from these bacteria facilitate the colonization and growth of CF pathogens like Pseudomonas aeruginosa. Here, a multi-omics study informed the control of putative anaerobic keystone species during a transition in antibiotic therapy of a CF patient. A quantitative metagenomics approach combining sequence data with epifluorescence microscopy showed that during periods of rapid lung function loss, the patient's lung microbiome was dominated by the anaerobic, mucus-degrading bacteria belonging to Streptococcus, Veillonella, and Prevotella genera. Untargeted metabolomics and community cultures identified high rates of fermentation in these sputa, with the accumulation of lactic acid, citric acid, and acetic acid. P. aeruginosa utilized these fermentation products for growth, as indicated by quantitative transcriptomics data. Transcription levels of P. aeruginosa genes for the utilization of fermentation products were proportional to the abundance of anaerobic bacteria. Clindamycin therapy targeting Gram-positive anaerobes rapidly suppressed anaerobic bacteria and the accumulation of fermentation products. Clindamycin also lowered the abundance and transcription of P. aeruginosa, even though this patient's strain was resistant to this antibiotic. The treatment stabilized the patient's lung function and improved respiratory health for two months, lengthening by a factor of four the between-hospitalization time for this patient. Killing anaerobes indirectly limited the growth of P. aeruginosa by disrupting the cross-feeding of fermentation products. This case study supports the hypothesis that facultative anaerobes operated as keystone species in this CF microbiome. Personalized multi-omics may become a viable approach for routine clinical diagnostics in the future, providing critical information to inform treatment decisions.
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37
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Lukasiak A, Zajac M. The Distribution and Role of the CFTR Protein in the Intracellular Compartments. MEMBRANES 2021; 11:membranes11110804. [PMID: 34832033 PMCID: PMC8618639 DOI: 10.3390/membranes11110804] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 10/18/2021] [Accepted: 10/21/2021] [Indexed: 12/11/2022]
Abstract
Cystic fibrosis is a hereditary disease that mainly affects secretory organs in humans. It is caused by mutations in the gene encoding CFTR with the most common phenylalanine deletion at position 508. CFTR is an anion channel mainly conducting Cl− across the apical membranes of many different epithelial cells, the impairment of which causes dysregulation of epithelial fluid secretion and thickening of the mucus. This, in turn, leads to the dysfunction of organs such as the lungs, pancreas, kidney and liver. The CFTR protein is mainly localized in the plasma membrane; however, there is a growing body of evidence that it is also present in the intracellular organelles such as the endosomes, lysosomes, phagosomes and mitochondria. Dysfunction of the CFTR protein affects not only the ion transport across the epithelial tissues, but also has an impact on the proper functioning of the intracellular compartments. The review aims to provide a summary of the present state of knowledge regarding CFTR localization and function in intracellular compartments, the physiological role of this localization and the consequences of protein dysfunction at cellular, epithelial and organ levels. An in-depth understanding of intracellular processes involved in CFTR impairment may reveal novel opportunities in pharmacological agents of cystic fibrosis.
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38
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Hanssens LS, Duchateau J, Casimir GJ. CFTR Protein: Not Just a Chloride Channel? Cells 2021; 10:2844. [PMID: 34831067 PMCID: PMC8616376 DOI: 10.3390/cells10112844] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Revised: 10/15/2021] [Accepted: 10/19/2021] [Indexed: 12/17/2022] Open
Abstract
Cystic fibrosis (CF) is a recessive genetic disease caused by mutations in a gene encoding a protein called Cystic Fibrosis Transmembrane Conductance Regulator (CFTR). The CFTR protein is known to acts as a chloride (Cl-) channel expressed in the exocrine glands of several body systems where it also regulates other ion channels, including the epithelial sodium (Na+) channel (ENaC) that plays a key role in salt absorption. This function is crucial to the osmotic balance of the mucus and its viscosity. However, the pathophysiology of CF is more challenging than a mere dysregulation of epithelial ion transport, mainly resulting in impaired mucociliary clearance (MCC) with consecutive bronchiectasis and in exocrine pancreatic insufficiency. This review shows that the CFTR protein is not just a chloride channel. For a long time, research in CF has focused on abnormal Cl- and Na+ transport. Yet, the CFTR protein also regulates numerous other pathways, such as the transport of HCO3-, glutathione and thiocyanate, immune cells, and the metabolism of lipids. It influences the pH homeostasis of airway surface liquid and thus the MCC as well as innate immunity leading to chronic infection and inflammation, all of which are considered as key pathophysiological characteristics of CF.
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Affiliation(s)
- Laurence S. Hanssens
- Department of Pediatric Pulmonology and Cystic Fibrosis Clinic, Hôpital Universitaire des Enfants Reine Fabiola, Université Libre de Bruxelles (ULB), Avenue J.J. Crocq 15, 1020 Brussels, Belgium;
| | - Jean Duchateau
- Laboratoire Académique de Pédiatrie, Hôpital Universitaire des Enfants Reine Fabiola, Université Libre de Bruxelles (ULB), Avenue J.J. Crocq 15, 1020 Brussels, Belgium;
| | - Georges J. Casimir
- Department of Pediatric Pulmonology and Cystic Fibrosis Clinic, Hôpital Universitaire des Enfants Reine Fabiola, Université Libre de Bruxelles (ULB), Avenue J.J. Crocq 15, 1020 Brussels, Belgium;
- Laboratoire Académique de Pédiatrie, Hôpital Universitaire des Enfants Reine Fabiola, Université Libre de Bruxelles (ULB), Avenue J.J. Crocq 15, 1020 Brussels, Belgium;
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Combined agonists act synergistically to increase mucociliary clearance in a cystic fibrosis airway model. Sci Rep 2021; 11:18828. [PMID: 34552115 PMCID: PMC8458446 DOI: 10.1038/s41598-021-98122-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Accepted: 09/03/2021] [Indexed: 11/30/2022] Open
Abstract
Mucus clearance, a primary innate defense mechanism of airways, is defective in patients with cystic fibrosis (CF) and CF animals. In previous work, the combination of a low dose of the cholinergic agonist, carbachol with forskolin or a β adrenergic agonist, isoproterenol synergistically increased mucociliary clearance velocity (MCCV) in ferret tracheas. Importantly, the present study shows that synergistic MCCV can also be produced in CF ferrets, with increases ~ 55% of WT. Synergistic MCCV was also produced in pigs. The combined agonists increased MCCV by increasing surface fluid via multiple mechanisms: increased fluid secretion from submucosal glands, increased anion secretion across surface epithelia and decreased Na+ absorption. To avoid bronchoconstriction, the cAMP agonist was applied 30 min before carbachol. This approach to increasing mucus clearance warrants testing for safety and efficacy in humans as a potential therapeutic for muco-obstructive diseases.
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40
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Rehman T, Karp PH, Tan P, Goodell BJ, Pezzulo AA, Thurman AL, Thornell IM, Durfey SL, Duffey ME, Stoltz DA, McKone EF, Singh PK, Welsh MJ. Inflammatory cytokines TNF-α and IL-17 enhance the efficacy of cystic fibrosis transmembrane conductance regulator modulators. J Clin Invest 2021; 131:e150398. [PMID: 34166230 DOI: 10.1172/jci150398] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Accepted: 06/22/2021] [Indexed: 12/12/2022] Open
Abstract
Without cystic fibrosis transmembrane conductance regulator-mediated (CFTR-mediated) HCO3- secretion, airway epithelia of newborns with cystic fibrosis (CF) produce an abnormally acidic airway surface liquid (ASL), and the decreased pH impairs respiratory host defenses. However, within a few months of birth, ASL pH increases to match that in non-CF airways. Although the physiological basis for the increase is unknown, this time course matches the development of inflammation in CF airways. To learn whether inflammation alters CF ASL pH, we treated CF epithelia with TNF-α and IL-17 (TNF-α+IL-17), 2 inflammatory cytokines that are elevated in CF airways. TNF-α+IL-17 markedly increased ASL pH by upregulating pendrin, an apical Cl-/HCO3- exchanger. Moreover, when CF epithelia were exposed to TNF-α+IL-17, clinically approved CFTR modulators further alkalinized ASL pH. As predicted by these results, in vivo data revealed a positive correlation between airway inflammation and CFTR modulator-induced improvement in lung function. These findings suggest that inflammation is a key regulator of HCO3- secretion in CF airways. Thus, they explain earlier observations that ASL pH increases after birth and indicate that, for similar levels of inflammation, the pH of CF ASL is abnormally acidic. These results also suggest that a non-cell-autonomous mechanism, airway inflammation, is an important determinant of the response to CFTR modulators.
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Affiliation(s)
- Tayyab Rehman
- Department of Internal Medicine and Pappajohn Biomedical Institute, Roy J. and Lucille A. Carver College of Medicine and
| | - Philip H Karp
- Department of Internal Medicine and Pappajohn Biomedical Institute, Roy J. and Lucille A. Carver College of Medicine and.,Howard Hughes Medical Institute, University of Iowa, Iowa City, Iowa, USA
| | - Ping Tan
- Department of Internal Medicine and Pappajohn Biomedical Institute, Roy J. and Lucille A. Carver College of Medicine and
| | - Brian J Goodell
- Department of Internal Medicine and Pappajohn Biomedical Institute, Roy J. and Lucille A. Carver College of Medicine and
| | - Alejandro A Pezzulo
- Department of Internal Medicine and Pappajohn Biomedical Institute, Roy J. and Lucille A. Carver College of Medicine and
| | - Andrew L Thurman
- Department of Internal Medicine and Pappajohn Biomedical Institute, Roy J. and Lucille A. Carver College of Medicine and
| | - Ian M Thornell
- Department of Internal Medicine and Pappajohn Biomedical Institute, Roy J. and Lucille A. Carver College of Medicine and
| | - Samantha L Durfey
- Departments of Medicine and Microbiology, University of Washington, Seattle, Washington, USA
| | - Michael E Duffey
- Department of Physiology and Biophysics, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, New York, USA
| | - David A Stoltz
- Department of Internal Medicine and Pappajohn Biomedical Institute, Roy J. and Lucille A. Carver College of Medicine and.,Department of Molecular Physiology and Biophysics, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa, USA
| | - Edward F McKone
- National Referral Centre for Adult Cystic Fibrosis, St. Vincent's University Hospital and University College Dublin School of Medicine, Dublin, Ireland
| | - Pradeep K Singh
- Departments of Medicine and Microbiology, University of Washington, Seattle, Washington, USA
| | - Michael J Welsh
- Department of Internal Medicine and Pappajohn Biomedical Institute, Roy J. and Lucille A. Carver College of Medicine and.,Howard Hughes Medical Institute, University of Iowa, Iowa City, Iowa, USA.,Department of Molecular Physiology and Biophysics, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, Iowa, USA
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Cmielewski P, Delhove J, Donnelley M, Parsons D. Assessment of Lentiviral Vector Mediated CFTR Correction in Mice Using an Improved Rapid in vivo Nasal Potential Difference Measurement Protocol. Front Pharmacol 2021; 12:714452. [PMID: 34385926 PMCID: PMC8353152 DOI: 10.3389/fphar.2021.714452] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Accepted: 07/05/2021] [Indexed: 12/20/2022] Open
Abstract
Cystic Fibrosis (CF) is caused by a defect in the CF transmembrane conductance regulator (CFTR) gene responsible for epithelial ion transport. Nasal potential difference (PD) measurement is a well established diagnostic technique for assessing the efficacy of therapies in CF patients and animal models. The aim was to establish a rapid nasal PD protocol in mice and quantify the efficacy of lentiviral (LV) vector-based CFTR gene therapy. Anaesthetised wild-type (WT) and CF mice were non-surgically intubated and nasal PD measurements were made using a range of buffer flow rates. Addition of the cAMP agonist, isoproterenol, to the buffer sequence was then examined. The optimised rapid PD technique was then used to assess CFTR function produced by second and third generation LV-CFTR vectors. V5 epitope tagged-CFTR in nasal tissue was identified by immunohistochemistry. When intubated, mice tolerated higher flow rates. Isoproterenol could discriminate between WT and CF mice. Improved chloride transport was observed for the second and third generation LV-CFTR vectors, with up to 60% correction of the cAMP-driven chloride response towards WT. V5-CFTR was located in ciliated epithelial cells. The rapid PD technique enables improved functional assessment of the bioelectrical ion transport defect for both current and potential CF therapies.
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Affiliation(s)
- P Cmielewski
- Respiratory and Sleep Medicine, Women's and Children's Hospital, Adelaide, SA, Australia.,Robinson Research Institute, University of Adelaide, Adelaide, SA, Australia.,Adelaide Medical School, University of Adelaide, Adelaide, SA, Australia
| | - J Delhove
- Respiratory and Sleep Medicine, Women's and Children's Hospital, Adelaide, SA, Australia.,Robinson Research Institute, University of Adelaide, Adelaide, SA, Australia.,Adelaide Medical School, University of Adelaide, Adelaide, SA, Australia
| | - M Donnelley
- Respiratory and Sleep Medicine, Women's and Children's Hospital, Adelaide, SA, Australia.,Robinson Research Institute, University of Adelaide, Adelaide, SA, Australia.,Adelaide Medical School, University of Adelaide, Adelaide, SA, Australia
| | - D Parsons
- Respiratory and Sleep Medicine, Women's and Children's Hospital, Adelaide, SA, Australia.,Robinson Research Institute, University of Adelaide, Adelaide, SA, Australia.,Adelaide Medical School, University of Adelaide, Adelaide, SA, Australia
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Budai-Szűcs M, Berkó S, Kovács A, Jaikumpun P, Ambrus R, Halász A, Szabó-Révész P, Csányi E, Zsembery Á. Rheological effects of hypertonic saline and sodium bicarbonate solutions on cystic fibrosis sputum in vitro. BMC Pulm Med 2021; 21:225. [PMID: 34253193 PMCID: PMC8276516 DOI: 10.1186/s12890-021-01599-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Accepted: 06/09/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Cystic fibrosis (CF) is a life-threatening multiorgan genetic disease, particularly affecting the lungs, where recurrent infections are the main cause of reduced life expectancy. In CF, mutations in the gene encoding the cystic fibrosis transmembrane conductance regulator (CFTR) protein impair transepithelial electrolyte and water transport, resulting in airway dehydration, and a thickening of the mucus associated with abnormal viscoelastic properties. Our aim was to develop a rheological method to assess the effects of hypertonic saline (NaCl) and NaHCO3 on CF sputum viscoelasticity in vitro, and to identify the critical steps in sample preparation and in the rheological measurements. METHODS Sputum samples were mixed with hypertonic salt solutions in vitro in a ratio of either 10:4 or 10:1. Distilled water was applied as a reference treatment. The rheological properties of sputum from CF patients, and the effects of these in vitro treatments, were studied with a rheometer at constant frequency and strain, followed by frequency sweep tests, where storage modulus (G'), loss modulus (G″) and loss factor were determined. RESULTS We identified three distinct categories of sputum: (i) highly elastic (G' > 100,000 Pa), (ii) elastic (100,000 Pa > G' > 1000 Pa), and (iii) viscoelastic (G' < 1000). At the higher additive ratio (10:4), all of the added solutions were found to significantly reduce the gel strength of the sputum, but the most pronounced changes were observed with NaHCO3 (p < 0.001). Samples with high elasticity exhibited the greatest changes while, for less elastic samples, a weakening of the gel structure was observed when they were treated with water or NaHCO3, but not with NaCl. For the viscoelastic samples, the additives did not cause significant changes in the parameters. When the lower additive ratio (10:1) was used, the mean values of the rheological parameters usually decreased, but the changes were not statistically significant. CONCLUSION Based on the rheological properties of the initial sputum samples, we can predict with some confidence the treatment efficacy of each of the alternative additives. The marked differences between the three categories suggest that it is advisable to evaluate each sample individually using a rheological approach such as that described here.
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Affiliation(s)
- Mária Budai-Szűcs
- Institute of Pharmaceutical Technology and Regulatory Affairs, University of Szeged, Szeged, Hungary.
| | - Szilvia Berkó
- Institute of Pharmaceutical Technology and Regulatory Affairs, University of Szeged, Szeged, Hungary
| | - Anita Kovács
- Institute of Pharmaceutical Technology and Regulatory Affairs, University of Szeged, Szeged, Hungary
| | | | - Rita Ambrus
- Institute of Pharmaceutical Technology and Regulatory Affairs, University of Szeged, Szeged, Hungary
| | - Adrien Halász
- National Korányi Institute for Pulmonology, Budapest, Hungary
| | - Piroska Szabó-Révész
- Institute of Pharmaceutical Technology and Regulatory Affairs, University of Szeged, Szeged, Hungary
| | - Erzsébet Csányi
- Institute of Pharmaceutical Technology and Regulatory Affairs, University of Szeged, Szeged, Hungary
| | - Ákos Zsembery
- Department of Oral Biology, Semmelweis University, Budapest, Hungary
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Harris A. Human molecular genetics and the long road to treating cystic fibrosis. Hum Mol Genet 2021; 30:R264-R273. [PMID: 34245257 DOI: 10.1093/hmg/ddab191] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Revised: 07/04/2021] [Accepted: 07/06/2021] [Indexed: 11/13/2022] Open
Abstract
The causative gene in cystic fibrosis was identified in 1989, three years before the publication of the first issue of Human Molecular Genetics. CFTR was among the first genes underlying a common inherited disorder to be cloned, and hence its subsequent utilization towards a cure for CF provides a roadmap for other monogenic diseases. Over the past 30 years the advances that built upon knowledge of the gene and the CFTR protein to develop effective therapeutics have been remarkable, and yet the setbacks have also been challenging. Technological progress in other fields has often circumvented the barriers. This review focuses on key aspects of CF diagnostics and current approaches to develop new therapies for all CFTR mutations. It also highlights the major research advances that underpinned progress towards treatments, and considers the remaining obstacles.
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Affiliation(s)
- Ann Harris
- Department of Genetics and Genome Sciences, Case Western Reserve University, Cleveland, OH, 44106, USA
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Bouzek DC, Abou Alaiwa MH, Adam RJ, Pezzulo AA, Reznikov LR, Cook DP, Aguilar Pescozo MI, Ten Eyck P, Wu C, Gross TJ, Hornick DB, Hoffman EA, Meyerholz DK, Stoltz DA. Early Lung Disease Exhibits Bacterial-Dependent and -Independent Abnormalities in Cystic Fibrosis Pigs. Am J Respir Crit Care Med 2021; 204:692-702. [PMID: 34170795 DOI: 10.1164/rccm.202102-0451oc] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
RATIONALE While it is clear that cystic fibrosis airway disease begins at a very young age, the early and subsequent steps in disease pathogenesis and the relative contribution of infection, mucus, and inflammation are not well understood. OBJECTIVES As one approach to assessing the early contribution of infection, we tested the hypothesis that early and continuous antibiotics would decrease the airway bacterial burden. We thought that, if it does, it might reveal aspects of the disease that are more or less sensitive to decreasing infection. METHODS Three groups of pigs were studied from birth until ~3 weeks of age: 1) wild-type, 2) cystic fibrosis, and 3) cystic fibrosis pigs treated continuously with broad-spectrum antibiotics from birth until study completion. Disease was assessed with chest computed tomography, histopathology, microbiology, and bronchoalveolar lavage. MEASUREMENTS AND MAIN RESULTS Disease was present by 3 weeks of age in cystic fibrosis pigs. Continuous antibiotics from birth improved chest computed tomography imaging abnormalities and airway mucus accumulation, but not airway inflammation in the cystic fibrosis pig model. However, reducing bacterial infection did not improve two disease features already present at birth in cystic fibrosis pigs, air trapping and submucosal gland duct plugging. In the cystic fibrosis sinuses, antibiotics did not prevent the development of infection, disease, or the number of bacteria but did alter the bacterial species. CONCLUSIONS These findings suggest that cystic fibrosis airway disease begins immediately following birth, and that early and continuous antibiotics impact some, but not all, aspects of CF lung disease development.
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Affiliation(s)
- Drake C Bouzek
- The University of Iowa Roy J and Lucille A Carver College of Medicine, 12243, Iowa City, Iowa, United States
| | - Mahmoud H Abou Alaiwa
- The University of Iowa Roy J and Lucille A Carver College of Medicine, 12243, Internal Medicine, Iowa City, Iowa, United States
| | - Ryan J Adam
- The University of Iowa Roy J and Lucille A Carver College of Medicine, 12243, Iowa City, Iowa, United States
| | - Alejandro A Pezzulo
- The University of Iowa Roy J and Lucille A Carver College of Medicine, 12243, Internal Medicine, Iowa City, Iowa, United States
| | - Leah R Reznikov
- University of Florida, 3463, Physiological Sciences, Gainesville, Florida, United States
| | - Daniel P Cook
- Vanderbilt University Medical Center, 12328, Department of Medicine, Nashville, Tennessee, United States
| | - Maria I Aguilar Pescozo
- The University of Iowa Roy J and Lucille A Carver College of Medicine, 12243, Iowa City, Iowa, United States
| | - Patrick Ten Eyck
- The University of Iowa, 4083, Institute for Clinical and Translational Science, Iowa City, Iowa, United States
| | - Chaorong Wu
- The University of Iowa Roy J and Lucille A Carver College of Medicine, 12243, Iowa City, Iowa, United States
| | - Thomas J Gross
- The University of Iowa Roy J and Lucille A Carver College of Medicine, 12243, Iowa City, Iowa, United States
| | - Douglas B Hornick
- The University of Iowa Roy J and Lucille A Carver College of Medicine, 12243, Iowa City, Iowa, United States
| | - Eric A Hoffman
- The University of Iowa Roy J and Lucille A Carver College of Medicine, 12243, Radiology, Iowa City, Iowa, United States
| | - David K Meyerholz
- The University of Iowa Roy J and Lucille A Carver College of Medicine, 12243, Pathology, Iowa City, Iowa, United States
| | - David A Stoltz
- The University of Iowa Roy J and Lucille A Carver College of Medicine, 12243, Iowa City, Iowa, United States;
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Ruksakiet K, Stercz B, Tóth G, Jaikumpun P, Gróf I, Tengölics R, Lohinai ZM, Horváth P, Deli MA, Steward MC, Dobay O, Zsembery Á. Bicarbonate Evokes Reciprocal Changes in Intracellular Cyclic di-GMP and Cyclic AMP Levels in Pseudomonas aeruginosa. BIOLOGY 2021; 10:biology10060519. [PMID: 34200909 PMCID: PMC8230467 DOI: 10.3390/biology10060519] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 06/04/2021] [Accepted: 06/08/2021] [Indexed: 11/23/2022]
Abstract
The formation of Pseudomonas aeruginosa biofilms in cystic fibrosis (CF) is one of the most common causes of morbidity and mortality in CF patients. Cyclic di-GMP and cyclic AMP are second messengers regulating the bacterial lifestyle transition in response to environmental signals. We aimed to investigate the effects of extracellular pH and bicarbonate on intracellular c-di-GMP and cAMP levels, and on biofilm formation. P. aeruginosa was inoculated in a brain−heart infusion medium supplemented with 25 and 50 mM NaCl in ambient air (pH adjusted to 7.4 and 7.7 respectively), or with 25 and 50 mM NaHCO3 in 5% CO2 (pH 7.4 and 7.7). After 16 h incubation, c-di-GMP and cAMP were extracted and their concentrations determined. Biofilm formation was investigated using an xCelligence real-time cell analyzer and by crystal violet assay. Our results show that HCO3− exposure decreased c-di-GMP and increased cAMP levels in a dose-dependent manner. Biofilm formation was also reduced after 48 h exposure to HCO3−. The reciprocal changes in second messenger concentrations were not influenced by changes in medium pH or osmolality. These findings indicate that HCO3− per se modulates the levels of c-di-GMP and cAMP, thereby inhibiting biofilm formation and promoting the planktonic lifestyle of the bacteria.
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Affiliation(s)
- Kasidid Ruksakiet
- Department of Oral Biology, Semmelweis University, H-1089 Budapest, Hungary; (K.R.); (P.J.); (M.C.S.)
- Department of Conservative Dentistry, Semmelweis University, H-1085 Budapest, Hungary;
| | - Balázs Stercz
- Institute of Medical Microbiology, Faculty of Medicine, Semmelweis University, H-1089 Budapest, Hungary; (B.S.); (O.D.)
| | - Gergő Tóth
- Department of Pharmaceutical Chemistry, Semmelweis University, H-1092 Budapest, Hungary; (G.T.); (P.H.)
| | - Pongsiri Jaikumpun
- Department of Oral Biology, Semmelweis University, H-1089 Budapest, Hungary; (K.R.); (P.J.); (M.C.S.)
| | - Ilona Gróf
- Institute of Biophysics, Biological Research Centre, H-6726 Szeged, Hungary; (I.G.); (M.A.D.)
| | - Roland Tengölics
- Institute of Biochemistry, Biological Research Centre, H-6726 Szeged, Hungary;
- HCEMM-BRC Metabolic Systems Biology Laboratory, H-6726 Szeged, Hungary
| | - Zsolt M. Lohinai
- Department of Conservative Dentistry, Semmelweis University, H-1085 Budapest, Hungary;
| | - Péter Horváth
- Department of Pharmaceutical Chemistry, Semmelweis University, H-1092 Budapest, Hungary; (G.T.); (P.H.)
| | - Mária A. Deli
- Institute of Biophysics, Biological Research Centre, H-6726 Szeged, Hungary; (I.G.); (M.A.D.)
| | - Martin C. Steward
- Department of Oral Biology, Semmelweis University, H-1089 Budapest, Hungary; (K.R.); (P.J.); (M.C.S.)
- School of Medical Sciences, University of Manchester, Manchester M13 9PL, UK
| | - Orsolya Dobay
- Institute of Medical Microbiology, Faculty of Medicine, Semmelweis University, H-1089 Budapest, Hungary; (B.S.); (O.D.)
| | - Ákos Zsembery
- Department of Oral Biology, Semmelweis University, H-1089 Budapest, Hungary; (K.R.); (P.J.); (M.C.S.)
- Correspondence:
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46
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Berg P, Svendsen SL, Sorensen MV, Schreiber R, Kunzelmann K, Leipziger J. The molecular mechanism of CFTR- and secretin-dependent renal bicarbonate excretion. J Physiol 2021; 599:3003-3011. [PMID: 33963548 DOI: 10.1113/jp281285] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2021] [Accepted: 04/12/2021] [Indexed: 11/08/2022] Open
Abstract
This review summarizes the newly discovered molecular mechanism of secretin-stimulated urine HCO3 - excretion and the role of cystic fibrosis transmembrane conductance regulator (CFTR) in renal HCO3 - excretion. The secretin receptor is functionally expressed in the basolateral membrane of the HCO3 - -secreting β-intercalated cells of the collecting duct. Here it activates a fast and efficient secretion of HCO3 - into the urine serving to normalize metabolic alkalosis. The ability to acutely increase renal base excretion is entirely dependent on functional pendrin (SLC26A4) and CFTR, and both proteins localize to the apical membrane of the β-intercalated cells. In cystic fibrosis mice and patients, this function is absent or markedly reduced. We discuss that the alkaline tide, namely the transient urine alkalinity after a meal, has now received a clear physiological explanation.
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Affiliation(s)
- Peder Berg
- Department of Biomedicine, Physiology, Health, Aarhus University, Aarhus, Denmark
| | - Samuel L Svendsen
- Department of Biomedicine, Physiology, Health, Aarhus University, Aarhus, Denmark
| | - Mads Vaarby Sorensen
- Department of Biomedicine, Physiology, Health, Aarhus University, Aarhus, Denmark
| | - Rainer Schreiber
- Department of Physiology, University of Regensburg, Regensburg, Germany
| | - Karl Kunzelmann
- Department of Physiology, University of Regensburg, Regensburg, Germany
| | - Jens Leipziger
- Department of Biomedicine, Physiology, Health, Aarhus University, Aarhus, Denmark
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47
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Treatment of Pulmonary Disease of Cystic Fibrosis: A Comprehensive Review. Antibiotics (Basel) 2021; 10:antibiotics10050486. [PMID: 33922413 PMCID: PMC8144952 DOI: 10.3390/antibiotics10050486] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Revised: 04/13/2021] [Accepted: 04/17/2021] [Indexed: 01/08/2023] Open
Abstract
Cystic fibrosis (CF) is a genetic disease that causes absence or dysfunction of a protein named transmembrane conductance regulatory protein (CFTR) that works as an anion channel. As a result, the secretions of the organs where CFTR is expressed are very viscous, so their functionality is altered. The main cause of morbidity is due to the involvement of the respiratory system as a result of recurrent respiratory infections by different pathogens. In recent decades, survival has been increasing, rising by around age 50. This is due to the monitoring of patients in multidisciplinary units, early diagnosis with neonatal screening, and advances in treatments. In this chapter, we will approach the different therapies used in CF for the treatment of symptoms, obstruction, inflammation, and infection. Moreover, we will discuss specific and personalized treatments to correct the defective gene and repair the altered protein CFTR. The obstacle for personalized CF treatment is to predict the drug response of patients due to genetic complexity and heterogeneity of uncommon mutations.
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48
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Kim D, Liao J, Scales NB, Martini C, Luan X, Abu-Arish A, Robert R, Luo Y, McKay GA, Nguyen D, Tewfik MA, Poirier CD, Matouk E, Ianowski JP, Frenkiel S, Hanrahan JW. Large pH oscillations promote host defense against human airways infection. J Exp Med 2021; 218:e20201831. [PMID: 33533914 PMCID: PMC7845918 DOI: 10.1084/jem.20201831] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 11/01/2020] [Accepted: 11/18/2020] [Indexed: 12/19/2022] Open
Abstract
The airway mucosal microenvironment is crucial for host defense against inhaled pathogens but remains poorly understood. We report here that the airway surface normally undergoes surprisingly large excursions in pH during breathing that can reach pH 9.0 during inhalation, making it the most alkaline fluid in the body. Transient alkalinization requires luminal bicarbonate and membrane-bound carbonic anhydrase 12 (CA12) and is antimicrobial. Luminal bicarbonate concentration and CA12 expression are both reduced in cystic fibrosis (CF), and mucus accumulation both buffers the pH and obstructs airflow, further suppressing the oscillations and bacterial-killing efficacy. Defective pH oscillations may compromise airway host defense in other respiratory diseases and explain CF-like airway infections in people with CA12 mutations.
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Affiliation(s)
- Dusik Kim
- Department of Physiology, McGill University, Montréal, Québec, Canada
- Cystic Fibrosis Translational Research Center, McGill University, Montréal, Québec, Canada
| | - Jie Liao
- Department of Physiology, McGill University, Montréal, Québec, Canada
- Cystic Fibrosis Translational Research Center, McGill University, Montréal, Québec, Canada
| | - Nathan B. Scales
- Department of Physiology, McGill University, Montréal, Québec, Canada
- Cystic Fibrosis Translational Research Center, McGill University, Montréal, Québec, Canada
| | - Carolina Martini
- Department of Physiology, McGill University, Montréal, Québec, Canada
- Cystic Fibrosis Translational Research Center, McGill University, Montréal, Québec, Canada
| | - Xiaojie Luan
- Department of Anatomy, Physiology and Pharmacology, College of Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Asmahan Abu-Arish
- Department of Physiology, McGill University, Montréal, Québec, Canada
- Cystic Fibrosis Translational Research Center, McGill University, Montréal, Québec, Canada
| | - Renaud Robert
- Department of Physiology, McGill University, Montréal, Québec, Canada
- Cystic Fibrosis Translational Research Center, McGill University, Montréal, Québec, Canada
| | - Yishan Luo
- Department of Physiology, McGill University, Montréal, Québec, Canada
- Cystic Fibrosis Translational Research Center, McGill University, Montréal, Québec, Canada
| | - Geoffrey A. McKay
- Department of Medicine, McGill University, Research Institute–McGill University Health Centre, Montréal, Québec, Canada
| | - Dao Nguyen
- Cystic Fibrosis Translational Research Center, McGill University, Montréal, Québec, Canada
- Department of Medicine, McGill University, Research Institute–McGill University Health Centre, Montréal, Québec, Canada
| | - Marc A. Tewfik
- Cystic Fibrosis Translational Research Center, McGill University, Montréal, Québec, Canada
- Department of Medicine, McGill University, Research Institute–McGill University Health Centre, Montréal, Québec, Canada
- Department of Otolaryngology–Head and Neck Surgery, McGill University Health Centre, Montréal, Québec, Canada
| | - Charles D. Poirier
- Centre Hospitalier de l'Université de Montréal, Montréal, Québec, Canada
| | - Elias Matouk
- Cystic Fibrosis Translational Research Center, McGill University, Montréal, Québec, Canada
- Adult Cystic Fibrosis Clinic, Montreal Chest Institute, McGill University Health Centre, Montréal, Québec, Canada
| | - Juan P. Ianowski
- Department of Anatomy, Physiology and Pharmacology, College of Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | - Saul Frenkiel
- Cystic Fibrosis Translational Research Center, McGill University, Montréal, Québec, Canada
- Department of Medicine, McGill University, Research Institute–McGill University Health Centre, Montréal, Québec, Canada
- Department of Otolaryngology–Head and Neck Surgery, McGill University Health Centre, Montréal, Québec, Canada
| | - John W. Hanrahan
- Department of Physiology, McGill University, Montréal, Québec, Canada
- Cystic Fibrosis Translational Research Center, McGill University, Montréal, Québec, Canada
- Department of Medicine, McGill University, Research Institute–McGill University Health Centre, Montréal, Québec, Canada
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49
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The Application of Bicarbonate Recovers the Chemical-Physical Properties of Airway Surface Liquid in Cystic Fibrosis Epithelia Models. BIOLOGY 2021; 10:biology10040278. [PMID: 33805545 PMCID: PMC8065534 DOI: 10.3390/biology10040278] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Revised: 03/22/2021] [Accepted: 03/24/2021] [Indexed: 01/24/2023]
Abstract
Cystic fibrosis (CF) is a genetic disease associated with the defective function of the cystic fibrosis transmembrane conductance regulator (CFTR) protein that causes obstructive disease and chronic bacterial infections in airway epithelia. Deletion of phenylalanine at position 508, p.F508del, the most frequent mutation among CF patients, causes a folding and traffic defect, resulting in a dramatic reduction in the CFTR expression. To investigate whether the direct application of bicarbonate could modify the properties of the airway surface liquid (ASL), we measured the micro-viscosity, fluid transport and pH of human bronchial epithelial cells monolayers. We have demonstrated that the treatment of a CF-epithelia with an iso-osmotic solution containing bicarbonate is capable of reducing both, the ASL viscosity and the apical fluid re-absorption. We suggest the possibility of design a supportive treatment based on topical application of bicarbonate, or any other alkaline buffer.
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50
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Zajac M, Dreano E, Edwards A, Planelles G, Sermet-Gaudelus I. Airway Surface Liquid pH Regulation in Airway Epithelium Current Understandings and Gaps in Knowledge. Int J Mol Sci 2021; 22:3384. [PMID: 33806154 PMCID: PMC8037888 DOI: 10.3390/ijms22073384] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Revised: 03/08/2021] [Accepted: 03/08/2021] [Indexed: 12/22/2022] Open
Abstract
Knowledge on the mechanisms of acid and base secretion in airways has progressed recently. The aim of this review is to summarize the known mechanisms of airway surface liquid (ASL) pH regulation and their implication in lung diseases. Normal ASL is slightly acidic relative to the interstitium, and defects in ASL pH regulation are associated with various respiratory diseases, such as cystic fibrosis. Basolateral bicarbonate (HCO3-) entry occurs via the electrogenic, coupled transport of sodium (Na+) and HCO3-, and, together with carbonic anhydrase enzymatic activity, provides HCO3- for apical secretion. The latter mainly involves CFTR, the apical chloride/bicarbonate exchanger pendrin and paracellular transport. Proton (H+) secretion into ASL is crucial to maintain its relative acidity compared to the blood. This is enabled by H+ apical secretion, mainly involving H+/K+ ATPase and vacuolar H+-ATPase that carry H+ against the electrochemical potential gradient. Paracellular HCO3- transport, the direction of which depends on the ASL pH value, acts as an ASL protective buffering mechanism. How the transepithelial transport of H+ and HCO3- is coordinated to tightly regulate ASL pH remains poorly understood, and should be the focus of new studies.
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Affiliation(s)
- Miroslaw Zajac
- Department of Physics and Biophysics, Institute of Biology, Warsaw University of Life Sciences, 02-776 Warsaw, Poland;
| | - Elise Dreano
- Institut Necker Enfants Malades, INSERM U1151, 75015 Paris, France;
- Centre de Recherche des Cordeliers, Sorbonne Université, INSERM, Université de Paris, 75006 Paris, France;
| | - Aurelie Edwards
- Department of Biomedical Engineering, Boston University, Boston, MA 02215, USA;
| | - Gabrielle Planelles
- Centre de Recherche des Cordeliers, Sorbonne Université, INSERM, Université de Paris, 75006 Paris, France;
- Laboratoire de Physiologie rénale et Tubulopathies, CNRS ERL 8228, 75006 Paris, France
| | - Isabelle Sermet-Gaudelus
- Institut Necker Enfants Malades, INSERM U1151, 75015 Paris, France;
- Centre de Recherche des Cordeliers, Sorbonne Université, INSERM, Université de Paris, 75006 Paris, France;
- Centre de Référence Maladies Rares, Mucoviscidose et Maladies de CFTR, Hôpital Necker Enfants Malades, 75015 Paris, France
- Clinical Trial Network, European Cystic Fibrosis Society, BT2 Belfast, Ireland
- European Respiratory Network Lung, 75006 Paris, France
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