1
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Yousefi Adlsadabad S, Hanrahan JW, Kakkar A. mRNA Delivery: Challenges and Advances through Polymeric Soft Nanoparticles. Int J Mol Sci 2024; 25:1739. [PMID: 38339015 PMCID: PMC10855060 DOI: 10.3390/ijms25031739] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Revised: 01/16/2024] [Accepted: 01/26/2024] [Indexed: 02/12/2024] Open
Abstract
Single-stranded messenger ribonucleic acid (mRNA) plays a pivotal role in transferring genetic information, and tremendous effort has been devoted over the years to utilize its transcription efficacy in therapeutic interventions for a variety of diseases with high morbidity and mortality. Lipid nanocarriers have been extensively investigated for mRNA delivery and enabled the rapid and successful development of mRNA vaccines against SARS-CoV-2. Some constraints of lipid nanocarriers have encouraged the development of alternative delivery systems, such as polymer-based soft nanoparticles, which offer a modular gene delivery platform. Such macromolecule-based nanocarriers can be synthetically articulated for tailored parameters including mRNA protection, loading efficacy, and targeted release. In this review, we highlight recent advances in the development of polymeric architectures for mRNA delivery, their limitations, and the challenges that still exist, with the aim of expediting further research and the clinical translation of such formulations.
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Affiliation(s)
| | - John W. Hanrahan
- Department of Physiology, McGill University, 3655 Promenade Sir-William-Osler, Montreal, QC H3G 1Y6, Canada;
| | - Ashok Kakkar
- Department of Chemistry, McGill University, 801 Sherbrooke St West, Montreal, QC H3A 0B8, Canada;
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2
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Ondra M, Lenart L, Centorame A, Dumut DC, He A, Zaidi SSZ, Hanrahan JW, De Sanctis JB, Radzioch D, Hajduch M. CRISPR/Cas9 bioluminescence-based assay for monitoring CFTR trafficking to the plasma membrane. Life Sci Alliance 2024; 7:e202302045. [PMID: 37918963 PMCID: PMC10622324 DOI: 10.26508/lsa.202302045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Revised: 10/20/2023] [Accepted: 10/20/2023] [Indexed: 11/04/2023] Open
Abstract
CFTR is a membrane protein that functions as an ion channel. Mutations that disrupt its biosynthesis, trafficking or function cause cystic fibrosis (CF). Here, we present a novel in vitro model system prepared using CRISPR/Cas9 genome editing with endogenously expressed WT-CFTR tagged with a HiBiT peptide. To enable the detection of CFTR in the plasma membrane of live cells, we inserted the HiBiT tag in the fourth extracellular loop of WT-CFTR. The 11-amino acid HiBiT tag binds with high affinity to a large inactive subunit (LgBiT), generating a reporter luciferase with bright luminescence. Nine homozygous clones with the HiBiT knock-in were identified from the 182 screened clones; two were genetically and functionally validated. In summary, this work describes the preparation and validation of a novel reporter cell line with the potential to be used as an ultimate building block for developing unique cellular CF models by CRISPR-mediated insertion of CF-causing mutations.
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Affiliation(s)
- Martin Ondra
- https://ror.org/04qxnmv42 Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacky University, Olomouc, Czech Republic
- https://ror.org/04qxnmv42 Czech Advanced Technology and Research Institute, Palacky University, Olomouc, Czech Republic
| | - Lukas Lenart
- https://ror.org/04qxnmv42 Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacky University, Olomouc, Czech Republic
| | - Amanda Centorame
- https://ror.org/01pxwe438 Faculty of Medicine and Health Sciences, McGill University, Montreal, Canada
- RI-MUHC, Montreal, Canada
| | - Daciana C Dumut
- https://ror.org/01pxwe438 Faculty of Medicine and Health Sciences, McGill University, Montreal, Canada
- RI-MUHC, Montreal, Canada
| | - Alexander He
- https://ror.org/01pxwe438 Physiology, McGill University, Montreal, Canada
| | | | - John W Hanrahan
- RI-MUHC, Montreal, Canada
- https://ror.org/01pxwe438 Physiology, McGill University, Montreal, Canada
| | - Juan Bautista De Sanctis
- https://ror.org/04qxnmv42 Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacky University, Olomouc, Czech Republic
| | - Danuta Radzioch
- https://ror.org/04qxnmv42 Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacky University, Olomouc, Czech Republic
- https://ror.org/01pxwe438 Faculty of Medicine and Health Sciences, McGill University, Montreal, Canada
- RI-MUHC, Montreal, Canada
| | - Marian Hajduch
- https://ror.org/04qxnmv42 Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacky University, Olomouc, Czech Republic
- https://ror.org/04qxnmv42 Czech Advanced Technology and Research Institute, Palacky University, Olomouc, Czech Republic
- Laboratory of Experimental Medicine, Institute of Molecular and Translational Medicine, University Hospital Olomouc, Olomouc, Czech Republic
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3
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Sato Y, Kim D, Turner MJ, Luo Y, Zaidi SSZ, Thomas DY, Hanrahan JW. Ionocyte-Specific Regulation of Cystic Fibrosis Transmembrane Conductance Regulator. Am J Respir Cell Mol Biol 2023; 69:281-294. [PMID: 36952679 DOI: 10.1165/rcmb.2022-0241oc] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2022] [Accepted: 03/23/2023] [Indexed: 03/25/2023] Open
Abstract
CFTR (cystic fibrosis transmembrane conductance regulator) is a tightly regulated anion channel that mediates chloride and bicarbonate conductance in many epithelia and in other tissues, but whether its regulation varies depending on the cell type has not been investigated. Epithelial CFTR expression is highest in rare cells called ionocytes. We studied CFTR regulation in control and ionocyte-enriched cultures by transducing bronchial basal cells with adenoviruses that encode only eGFP or FOXI1 (forkhead box I1) + eGFP as separate polypeptides. FOXI1 dramatically increased the number of transcripts for ionocyte markers ASCL3 (Achaete-Scute Family BHLH Transcription Factor 3), BSND, ATP6V1G3, ATP6V0D2, KCNMA1, and CFTR without altering those for secretory (SCGB1A1), basal (KRT5, KRT6, TP63), goblet (MUC5AC), or ciliated (FOXJ1) cells. The number of cells displaying strong FOXI1 expression was increased 7-fold, and there was no evidence for a broad increase in background immunofluorescence. Total CFTR mRNA and protein levels increased 10-fold and 2.5-fold, respectively. Ionocyte-enriched cultures displayed elevated basal current, increased adenylyl cyclase 5 expression, and tonic suppression of CFTR activity by the phosphodiesterase PDE1C, which has not been shown previously to regulate CFTR activity. The results indicate that CFTR regulation depends on cell type and identifies PDE1C as a potential target for therapeutics that aim to increase CFTR function specifically in ionocytes.
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Affiliation(s)
- Yukiko Sato
- Department of Physiology
- Cystic Fibrosis Translational Research Center
| | - Dusik Kim
- Department of Physiology
- Cystic Fibrosis Translational Research Center
| | - Mark J Turner
- Department of Physiology
- Cystic Fibrosis Translational Research Center
| | - Yishan Luo
- Department of Physiology
- Cystic Fibrosis Translational Research Center
| | | | - David Y Thomas
- Cystic Fibrosis Translational Research Center
- Department of Biochemistry, McGill University, Montreal, Quebec, Canada, and
| | - John W Hanrahan
- Department of Physiology
- Cystic Fibrosis Translational Research Center
- Research Institute, McGill University Health Centre, Montreal, Quebec, Canada
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4
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Hanrahan JW, Abu-Arish A, Wong FH, Turner MJ, Carlile GW, Thomas DY, Cantin AM. COPD and the modulation of CFTR by acute exposure to cigarette smoke. Am J Physiol Cell Physiol 2022; 323:C1374-C1392. [PMID: 36121129 DOI: 10.1152/ajpcell.00356.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Chronic obstructive lung disease (COPD) is a leading cause of death and cigarette smoke is the main risk factor. Detecting its earliest stages and preventing a decline in lung function are key goals. The pathogenesis of COPD is complex but has some similarities to cystic fibrosis (CF), a disease caused by mutations in the cftr gene. CF leads to chronic inflammation, abnormal mucus and cycles of infection. Cigarette smoke exposure also causes CFTR dysfunction, and it is probably not a coincidence that inflammation, mucus obstruction and infections are also characteristics of COPD, although the exacerbations can be quite different. We review here the acute effects of cigarette smoke on CFTR function and its potential role in COPD. Understanding CFTR regulation by cigarette smoke may identify novel drug targets and facilitate the development of therapeutics that reduce the progression and severity of COPD.
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Affiliation(s)
- John W Hanrahan
- Department of Physiology, McGill University, Montreal, QC, Canada.,CF Translational Research Centre, McGill University, Montreal, QC, Canada.,Research Institute of McGill University Hospital Centre, Montreal, Quebec, Canada
| | - Asmahan Abu-Arish
- Department of Anatomy, Physiology and Pharmacology, College of Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
| | | | - Mark J Turner
- Health Canada, Tunney's Pasture, Ottawa, Ontario, Canada
| | - Graeme W Carlile
- CF Translational Research Centre, McGill University, Montreal, QC, Canada.,Department of Biochemistry, McGill University, Montreal, Quebec, Canada
| | - David Y Thomas
- CF Translational Research Centre, McGill University, Montreal, QC, Canada.,Department of Biochemistry, McGill University, Montreal, Quebec, Canada
| | - Andre M Cantin
- CF Translational Research Centre, McGill University, Montreal, QC, Canada.,Pulmonary Division, Faculty of Medicine, Université de Sherbrooke, Sherbrooke, Quebec, Canada
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5
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Stevers LM, Wolter M, Carlile GW, Macdonald D, Richard L, Gielkens F, Hanrahan JW, Thomas DY, Chakka SK, Peterson ML, Thomas H, Brunsveld L, Ottmann C. Macrocycle-stabilization of its interaction with 14-3-3 increases plasma membrane localization and activity of CFTR. Nat Commun 2022; 13:3586. [PMID: 35739107 PMCID: PMC9226124 DOI: 10.1038/s41467-022-31206-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2021] [Accepted: 06/07/2022] [Indexed: 11/09/2022] Open
Abstract
Impaired activity of the chloride channel CFTR is the cause of cystic fibrosis. 14-3-3 proteins have been shown to stabilize CFTR and increase its biogenesis and activity. Here, we report the identification and mechanism of action of a macrocycle stabilizing the 14-3-3/CFTR complex. This molecule rescues plasma membrane localization and chloride transport of F508del-CFTR and works additively with the CFTR pharmacological chaperone corrector lumacaftor (VX-809) and the triple combination Trikafta®. This macrocycle is a useful tool to study the CFTR/14-3-3 interaction and the potential of molecular glues in cystic fibrosis therapeutics.
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Affiliation(s)
- Loes M Stevers
- Laboratory of Chemical Biology, Department of Biomedical Engineering and Institute for Complex Molecular Systems, Eindhoven University of Technology, Eindhoven, The Netherlands
| | - Madita Wolter
- Laboratory of Chemical Biology, Department of Biomedical Engineering and Institute for Complex Molecular Systems, Eindhoven University of Technology, Eindhoven, The Netherlands
| | - Graeme W Carlile
- Cystic Fibrosis Translational Research Centre, Department of Biochemistry and Physiology, McGill University, Montreal, QC, Canada
| | - Dwight Macdonald
- Cyclenium Pharma Inc., 7171 rue Frederick Banting, Montreal, Quebec, Canada
| | - Luc Richard
- Cyclenium Pharma Inc., 7171 rue Frederick Banting, Montreal, Quebec, Canada
| | - Frank Gielkens
- Laboratory of Chemical Biology, Department of Biomedical Engineering and Institute for Complex Molecular Systems, Eindhoven University of Technology, Eindhoven, The Netherlands
| | - John W Hanrahan
- Cystic Fibrosis Translational Research Centre, Department of Biochemistry and Physiology, McGill University, Montreal, QC, Canada
| | - David Y Thomas
- Cystic Fibrosis Translational Research Centre, Department of Biochemistry and Physiology, McGill University, Montreal, QC, Canada
| | - Sai Kumar Chakka
- Cyclenium Pharma Inc., 7171 rue Frederick Banting, Montreal, Quebec, Canada
| | - Mark L Peterson
- Cyclenium Pharma Inc., 7171 rue Frederick Banting, Montreal, Quebec, Canada
| | - Helmut Thomas
- Cyclenium Pharma Inc., 7171 rue Frederick Banting, Montreal, Quebec, Canada
| | - Luc Brunsveld
- Laboratory of Chemical Biology, Department of Biomedical Engineering and Institute for Complex Molecular Systems, Eindhoven University of Technology, Eindhoven, The Netherlands
| | - Christian Ottmann
- Laboratory of Chemical Biology, Department of Biomedical Engineering and Institute for Complex Molecular Systems, Eindhoven University of Technology, Eindhoven, The Netherlands.
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6
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Centorame A, Dumut DC, Youssef M, Ondra M, Kianicka I, Shah J, Paun RA, Ozdian T, Hanrahan JW, Gusev E, Petrof B, Hajduch M, Pislariu R, De Sanctis JB, Radzioch D. Treatment With LAU-7b Complements CFTR Modulator Therapy by Improving Lung Physiology and Normalizing Lipid Imbalance Associated With CF Lung Disease. Front Pharmacol 2022; 13:876842. [PMID: 35668939 PMCID: PMC9163687 DOI: 10.3389/fphar.2022.876842] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Accepted: 04/08/2022] [Indexed: 11/13/2022] Open
Abstract
Cystic fibrosis (CF) is the most common autosomal recessive genetic disease in Caucasians, affecting more than 100,000 individuals worldwide. It is caused by pathogenic variants in the gene encoding CFTR, an anion channel at the plasma membrane of epithelial and other cells. Many CF pathogenic variants disrupt the biosynthesis and trafficking of CFTR or reduce its ion channel function. The most frequent mutation, loss of a phenylalanine at position 508 (F508del), leads to misfolding, retention in the endoplasmic reticulum, and premature degradation of the protein. The therapeutics available for treating CF lung disease include antibiotics, mucolytics, bronchodilators, physiotherapy, and most recently CFTR modulators. To date, no cure for this life shortening disease has been found. Treatment with the Triple combination drug therapy, TRIKAFTA®, is composed of three drugs: Elexacaftor (VX-445), Tezacaftor (VX-661) and Ivacaftor (VX-770). This therapy, benefits persons with CF, improving their weight, lung function, energy levels (as defined by reduced fatigue), and overall quality of life. We examined the effect of combining LAU-7b oral treatment and Triple therapy combination on lung function in a F508deltm1EUR mouse model that displays lung abnormalities relevant to human CF. We assessed lung function, lung histopathology, protein oxidation, lipid oxidation, and fatty acid and lipid profiles in F508deltm1EUR mice.
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Affiliation(s)
- Amanda Centorame
- Faculty of Medicine, McGill University, Montreal, QC, Canada
- Infectious Diseases and Immunity in Global Health, Research Institute of the McGill University Health Centre, Montreal, QC, Canada
| | - Daciana Catalina Dumut
- Faculty of Medicine, McGill University, Montreal, QC, Canada
- Infectious Diseases and Immunity in Global Health, Research Institute of the McGill University Health Centre, Montreal, QC, Canada
| | - Mina Youssef
- Infectious Diseases and Immunity in Global Health, Research Institute of the McGill University Health Centre, Montreal, QC, Canada
| | - Martin Ondra
- Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacky University, Olomouc, Czechia
- Czech Advanced Technology and Research Institute, Palacky University, Olomouc, Czechia
| | | | - Juhi Shah
- Infectious Diseases and Immunity in Global Health, Research Institute of the McGill University Health Centre, Montreal, QC, Canada
| | - Radu Alexandru Paun
- Infectious Diseases and Immunity in Global Health, Research Institute of the McGill University Health Centre, Montreal, QC, Canada
- Department of Biomedical Engineering, McGill University, Montreal, QC, Canada
| | - Tomas Ozdian
- Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacky University, Olomouc, Czechia
| | - John W. Hanrahan
- Department of Physiology, McGill University, Montreal, QC, Canada
| | - Ekaterina Gusev
- Meakins-Christie Laboratories, The Centre for Respiratory Research at McGill University and the Research Institute of the McGill University Health Centre, Montreal, QC, Canada
| | - Basil Petrof
- Meakins-Christie Laboratories, The Centre for Respiratory Research at McGill University and the Research Institute of the McGill University Health Centre, Montreal, QC, Canada
| | - Marian Hajduch
- Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacky University, Olomouc, Czechia
- Czech Advanced Technology and Research Institute, Palacky University, Olomouc, Czechia
| | | | - Juan Bautista De Sanctis
- Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacky University, Olomouc, Czechia
- Czech Advanced Technology and Research Institute, Palacky University, Olomouc, Czechia
| | - Danuta Radzioch
- Faculty of Medicine, McGill University, Montreal, QC, Canada
- Infectious Diseases and Immunity in Global Health, Research Institute of the McGill University Health Centre, Montreal, QC, Canada
- Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacky University, Olomouc, Czechia
- Laurent Pharmaceuticals, Montreal, QC, Canada
- *Correspondence: Danuta Radzioch,
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7
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Abu-Arish A, Pandžić E, Luo Y, Sato Y, Turner MJ, Wiseman PW, Hanrahan JW. Lipid-driven CFTR clustering is impaired in CF and restored by corrector drugs. J Cell Sci 2022; 135:274066. [PMID: 35060604 PMCID: PMC8976878 DOI: 10.1242/jcs.259002] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Accepted: 01/08/2022] [Indexed: 11/20/2022] Open
Abstract
Membrane proteins often cluster in nanoscale membrane domains (lipid rafts) that coalesce into ceramide-rich platforms during cell stress, however the clustering mechanisms remain uncertain. The cystic fibrosis transmembrane conductance regulator (CFTR), which is mutated in cystic fibrosis (CF), forms clusters that are cholesterol-dependent and become incorporated into long-lived platforms during hormonal stimulation. We report here that clustering does not involve known tethering interactions of CFTR with PDZ domain proteins, filamin A or the actin cytoskeleton. It also does not require CFTR palmitoylation but is critically dependent on membrane lipid order and is induced by detergents that increase the phase separation of membrane lipids. Clustering and integration of CFTR into ceramide-rich platforms are abolished by the disease mutations F508del and S13F and rescued by the CFTR modulators elexacaftor+tezacaftor. These results indicate CF therapeutics that correct mutant protein folding restore both trafficking and normal lipid interactions in the plasma membrane.
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Affiliation(s)
- Asmahan Abu-Arish
- Department of Physiology, McGill University, Montréal QC H3G 1Y6, Canada
- Cystic Fibrosis Translational Research centre, McGill University, Canada
| | - Elvis Pandžić
- UNSW Australia, Biomedical Imaging Facility, Mark Wainwright Analytical Center, Sydney, Australia
| | - Yishan Luo
- Department of Physiology, McGill University, Montréal QC H3G 1Y6, Canada
- Cystic Fibrosis Translational Research centre, McGill University, Canada
| | - Yukiko Sato
- Department of Physiology, McGill University, Montréal QC H3G 1Y6, Canada
- Cystic Fibrosis Translational Research centre, McGill University, Canada
| | - Mark J. Turner
- Department of Physiology, McGill University, Montréal QC H3G 1Y6, Canada
- Cystic Fibrosis Translational Research centre, McGill University, Canada
| | - Paul W. Wiseman
- Department of Chemistry and Department of Physics, McGill University, Montréal, QC, Canada
| | - John W. Hanrahan
- Department of Physiology, McGill University, Montréal QC H3G 1Y6, Canada
- Cystic Fibrosis Translational Research centre, McGill University, Canada
- Research Institute of the McGill University Health Centre, Canada
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8
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Turner MJ, Sato Y, Thomas DY, Abbott-Banner K, Hanrahan JW. Phosphodiesterase 8A Regulates CFTR Activity in Airway Epithelial Cells. Cell Physiol Biochem 2021; 55:784-804. [PMID: 34936285 DOI: 10.33594/000000477] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/09/2021] [Indexed: 11/06/2022] Open
Abstract
BACKGROUND/AIMS Cystic fibrosis transmembrane conductance regulator (CFTR), the anion channel that is defective in cystic fibrosis (CF), is phosphorylated and activated by cAMP-dependent protein kinase (PKA). cAMP levels are downregulated by a large family of phosphodiesterases that have variable expression in different cell types. We have previously observed high levels of PDE8A expression in well-differentiated primary human bronchial epithelial (pHBE) cells and thus aimed to assess whether it played a role in cAMP-dependent regulation of CFTR activity. METHODS We assessed the effect of the selective PDE8 inhibitor PF-04957325 (PF) on intracellular cAMP levels ([cAMP]i) in well differentiated pHBE cells from non-CF or CF donors and also in CFBE41o- cells that stably express wild-type CFTR (CFBE41o- WT) using ELISA and FRET-FLIM microscopy. CFTR channel function was also measured using electrophysiological recordings from pHBE and CFBE41o- WT cells mounted in Ussing Chambers. RESULTS PDE8 inhibition elevated [cAMP]i in well-differentiated pHBE cells and stimulated wild-type CFTR-dependent ion transport under basal conditions or after cells had been pre-stimulated with physiological cAMP-elevating agents. The response to PDE8 inhibition was larger than to PDE3 or PDE5 inhibition but smaller and synergistic with that elicited by PDE4 inhibition. CRISPR Cas9-mediated knockdown of PDE8A enhanced CFTR gene and protein expression yet reduced the effect of PDE8 inhibition. Acute pharmacological inhibition PDE8 increased CFTR activity in CF pHBE cells (F508del/F508del and F508del/R117H-5T) treated with clinically-approved CFTR modulators. CONCLUSION These results provide the first evidence that PDE8A regulates CFTR and identifies PDE8A as a potential target for adjunct therapies to treat CF.
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Affiliation(s)
- Mark J Turner
- Department of Physiology, McGill University, Montréal, QC, Canada, .,Cystic Fibrosis Translational Research Centre, McGill University, Montréal, QC, Canada
| | - Yukiko Sato
- Department of Physiology, McGill University, Montréal, QC, Canada.,Cystic Fibrosis Translational Research Centre, McGill University, Montréal, QC, Canada
| | - David Y Thomas
- Cystic Fibrosis Translational Research Centre, McGill University, Montréal, QC, Canada.,Department of Biochemistry, McGill University, Montréal, QC, Canada
| | | | - John W Hanrahan
- Department of Physiology, McGill University, Montréal, QC, Canada.,Cystic Fibrosis Translational Research Centre, McGill University, Montréal, QC, Canada
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9
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Sato Y, Mustafina KR, Luo Y, Martini C, Thomas DY, Wiseman PW, Hanrahan JW. Nonspecific binding of common anti-CFTR antibodies in ciliated cells of human airway epithelium. Sci Rep 2021; 11:23256. [PMID: 34853321 PMCID: PMC8636639 DOI: 10.1038/s41598-021-02420-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Accepted: 11/11/2021] [Indexed: 11/10/2022] Open
Abstract
There is evidence that the cystic fibrosis transmembrane conductance regulator (CFTR) anion channel is highly expressed at the apical pole of ciliated cells in human bronchial epithelium (HBE), however recent studies have detected little CFTR mRNA in those cells. To understand this discrepancy we immunostained well differentiated primary HBE cells using CFTR antibodies. We confirmed apical immunofluorescence in ciliated cells and quantified the covariance of the fluorescence signals and that of an antibody against the ciliary marker centrin-2 using image cross-correlation spectroscopy (ICCS). Super-resolution stimulated emission depletion (STED) imaging localized the immunofluorescence in distinct clusters at the bases of the cilia. However, similar apical fluorescence was observed when the monoclonal CFTR antibodies 596, 528 and 769 were used to immunostain ciliated cells expressing F508del-CFTR, or cells lacking CFTR due to a Class I mutation. A BLAST search using the CFTR epitope identified a similar amino acid sequence in the ciliary protein rootletin X1. Its expression level correlated with the intensity of immunostaining by CFTR antibodies and it was detected by 596 antibody after transfection into CFBE cells. These results may explain the high apparent expression of CFTR in ciliated cells and reports of anomalous apical immunofluorescence in well differentiated cells that express F508del-CFTR.
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Affiliation(s)
- Yukiko Sato
- Department of Physiology, McGill University, McIntyre Medical Sciences Building, 3655 Promenade Sir William Osler, Montréal, QC, H3G 1Y6, Canada.,Cystic Fibrosis Translational Research Centre, McGill University, Montréal, Canada
| | - Kamila R Mustafina
- Cystic Fibrosis Translational Research Centre, McGill University, Montréal, Canada.,Department of Chemistry, McGill University, Montréal, Canada
| | - Yishan Luo
- Department of Physiology, McGill University, McIntyre Medical Sciences Building, 3655 Promenade Sir William Osler, Montréal, QC, H3G 1Y6, Canada.,Cystic Fibrosis Translational Research Centre, McGill University, Montréal, Canada
| | - Carolina Martini
- Department of Physiology, McGill University, McIntyre Medical Sciences Building, 3655 Promenade Sir William Osler, Montréal, QC, H3G 1Y6, Canada.,Cystic Fibrosis Translational Research Centre, McGill University, Montréal, Canada
| | - David Y Thomas
- Cystic Fibrosis Translational Research Centre, McGill University, Montréal, Canada.,Department of Biochemistry, McGill University, Montréal, Canada
| | - Paul W Wiseman
- Cystic Fibrosis Translational Research Centre, McGill University, Montréal, Canada.,Department of Chemistry, McGill University, Montréal, Canada.,Department of Physics, McGill University, Montréal, Canada
| | - John W Hanrahan
- Department of Physiology, McGill University, McIntyre Medical Sciences Building, 3655 Promenade Sir William Osler, Montréal, QC, H3G 1Y6, Canada. .,Cystic Fibrosis Translational Research Centre, McGill University, Montréal, Canada. .,Research Institute - McGill University Health Centre, Montréal, Canada.
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10
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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11
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Kouthouridis S, Goepp J, Martini C, Matthes E, Hanrahan JW, Moraes C. Oxygenation as a driving factor in epithelial differentiation at the air-liquid interface. Integr Biol (Camb) 2021; 13:61-72. [PMID: 33677549 PMCID: PMC7965686 DOI: 10.1093/intbio/zyab002] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Revised: 12/13/2020] [Accepted: 01/12/2021] [Indexed: 01/05/2023]
Abstract
Culture at the air-liquid interface is broadly accepted as necessary for differentiation of cultured epithelial cells towards an in vivo-like phenotype. However, air-liquid interface cultures are expensive, laborious and challenging to scale for increased throughput applications. Deconstructing the microenvironmental parameters that drive these differentiation processes could circumvent these limitations, and here we hypothesize that reduced oxygenation due to diffusion limitations in liquid media limits differentiation in submerged cultures; and that this phenotype can be rescued by recreating normoxic conditions at the epithelial monolayer, even under submerged conditions. Guided by computational models, hyperoxygenation of atmospheric conditions was applied to manipulate oxygenation at the monolayer surface. The impact of this rescue condition was confirmed by assessing protein expression of hypoxia-sensitive markers. Differentiation of primary human bronchial epithelial cells isolated from healthy patients was then assessed in air-liquid interface, submerged and hyperoxygenated submerged culture conditions. Markers of differentiation, including epithelial layer thickness, tight junction formation, ciliated surface area and functional capacity for mucociliary clearance, were assessed and found to improve significantly in hyperoxygenated submerged cultures, beyond standard air-liquid interface or submerged culture conditions. These results demonstrate that an air-liquid interface is not necessary to produce highly differentiated epithelial structures, and that increased availability of oxygen and nutrient media can be leveraged as important strategies to improve epithelial differentiation for applications in respiratory toxicology and therapeutic development.
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Affiliation(s)
- Sonya Kouthouridis
- Department of Chemical Engineering, McGill University, Montreal, Canada
- Department of Chemical Engineering, McMaster University, Hamilton, Canada
| | - Julie Goepp
- Department of Physiology, Cystic Fibrosis Translational Research Centre, McGill University, Montreal, Canada
| | | | | | - John W Hanrahan
- Department of Physiology, Cystic Fibrosis Translational Research Centre, McGill University, Montreal, Canada
- Department of Physiology, McGill University, Montreal, Canada
| | - Christopher Moraes
- Department of Chemical Engineering, McGill University, Montreal, Canada
- Department of Physiology, Cystic Fibrosis Translational Research Centre, McGill University, Montreal, Canada
- Department of Biological and Biomedical Engineering, McGill University, Montreal, Canada
- Faculty of Medicine, Rosalind and Morris Goodman Cancer Research Center, Montreal, Canada
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12
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Turner MJ, Abbott-Banner K, Thomas DY, Hanrahan JW. Cyclic nucleotide phosphodiesterase inhibitors as therapeutic interventions for cystic fibrosis. Pharmacol Ther 2021; 224:107826. [PMID: 33662448 DOI: 10.1016/j.pharmthera.2021.107826] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Revised: 01/05/2021] [Accepted: 02/22/2021] [Indexed: 12/13/2022]
Abstract
Cystic Fibrosis (CF) lung disease results from mutations in the CFTR anion channel that reduce anion and fluid secretion by airway epithelia. Impaired secretion compromises airway innate defence mechanisms and leads to bacterial colonization, excessive inflammation and tissue damage; thus, restoration of CFTR function is the goal of many CF therapies. CFTR channels are activated by cyclic nucleotide-dependent protein kinases. The second messengers 3'5'-cAMP and 3'5'-cGMP are hydrolysed by a large family of cyclic nucleotide phosphodiesterases that provide subcellular spatial and temporal control of cyclic nucleotide-dependent signalling. Selective inhibition of these enzymes elevates cyclic nucleotide levels, leading to activation of CFTR and other downstream effectors. Here we examine members of the PDE family that are likely to regulate CFTR-dependent ion and fluid secretion in the airways and discuss other actions of PDE inhibitors that can influence cyclic nucleotide-regulated mucociliary transport, inflammation and bronchodilation. Finally, we review PDE inhibitors and the potential benefits they could provide as CF therapeutics.
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Affiliation(s)
- Mark J Turner
- Department of Physiology, McGill University, Montreal, QC, Canada; Cystic Fibrosis Translational Research Centre, McGill University, Montreal, QC, Canada.
| | | | - David Y Thomas
- Cystic Fibrosis Translational Research Centre, McGill University, Montreal, QC, Canada; Department of Biochemistry, McGill University, Montreal, QC, Canada
| | - John W Hanrahan
- Department of Physiology, McGill University, Montreal, QC, Canada; Cystic Fibrosis Translational Research Centre, McGill University, Montreal, QC, Canada
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13
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Veltman M, De Sanctis JB, Stolarczyk M, Klymiuk N, Bähr A, Brouwer RW, Oole E, Shah J, Ozdian T, Liao J, Martini C, Radzioch D, Hanrahan JW, Scholte BJ. CFTR Correctors and Antioxidants Partially Normalize Lipid Imbalance but not Abnormal Basal Inflammatory Cytokine Profile in CF Bronchial Epithelial Cells. Front Physiol 2021; 12:619442. [PMID: 33613309 PMCID: PMC7891400 DOI: 10.3389/fphys.2021.619442] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Accepted: 01/07/2021] [Indexed: 12/20/2022] Open
Abstract
A deficiency in cystic fibrosis transmembrane conductance regulator (CFTR) function in CF leads to chronic lung disease. CF is associated with abnormalities in fatty acids, ceramides, and cholesterol, their relationship with CF lung pathology is not completely understood. Therefore, we examined the impact of CFTR deficiency on lipid metabolism and pro-inflammatory signaling in airway epithelium using mass spectrometric, protein array. We observed a striking imbalance in fatty acid and ceramide metabolism, associated with chronic oxidative stress under basal conditions in CF mouse lung and well-differentiated bronchial epithelial cell cultures of CFTR knock out pig and CF patients. Cell-autonomous features of all three CF models included high ratios of ω-6- to ω-3-polyunsaturated fatty acids and of long- to very long-chain ceramide species (LCC/VLCC), reduced levels of total ceramides and ceramide precursors. In addition to the retinoic acid analog fenretinide, the anti-oxidants glutathione (GSH) and deferoxamine partially corrected the lipid profile indicating that oxidative stress may promote the lipid abnormalities. CFTR-targeted modulators reduced the lipid imbalance and oxidative stress, confirming the CFTR dependence of lipid ratios. However, despite functional correction of CF cells up to 60% of non-CF in Ussing chamber experiments, a 72-h triple compound treatment (elexacaftor/tezacaftor/ivacaftor surrogate) did not completely normalize lipid imbalance or oxidative stress. Protein array analysis revealed differential expression and shedding of cytokines and growth factors from CF epithelial cells compared to non-CF cells, consistent with sterile inflammation and tissue remodeling under basal conditions, including enhanced secretion of the neutrophil activator CXCL5, and the T-cell activator CCL17. However, treatment with antioxidants or CFTR modulators that mimic the approved combination therapies, ivacaftor/lumacaftor and ivacaftor/tezacaftor/elexacaftor, did not effectively suppress the inflammatory phenotype. We propose that CFTR deficiency causes oxidative stress in CF airway epithelium, affecting multiple bioactive lipid metabolic pathways, which likely play a role in CF lung disease progression. A combination of anti-oxidant, anti-inflammatory and CFTR targeted therapeutics may be required for full correction of the CF phenotype.
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Affiliation(s)
- Mieke Veltman
- Cell Biology Department, Erasmus Medical Center, Rotterdam, Netherlands.,Pediatric Pulmonology, Sophia Children's Hospital, Erasmus Medical Center, Rotterdam, Netherlands
| | - Juan B De Sanctis
- Faculty of Medicine and Dentistry, Institute of Molecular and Translational Medicine, Palacký University, Olomouc, Czechia
| | - Marta Stolarczyk
- Cell Biology Department, Erasmus Medical Center, Rotterdam, Netherlands
| | - Nikolai Klymiuk
- Large Animal Models for Cardiovascular Research, TU Munich, Munich, Germany.,Center for Innovative Medical Models, LMU Munich, Munich, Germany
| | - Andrea Bähr
- Large Animal Models for Cardiovascular Research, TU Munich, Munich, Germany.,Center for Innovative Medical Models, LMU Munich, Munich, Germany
| | - Rutger W Brouwer
- Cell Biology Department, Erasmus Medical Center, Rotterdam, Netherlands.,Center for Biomics, Erasmus Medical Center, Rotterdam, Netherlands
| | - Edwin Oole
- Cell Biology Department, Erasmus Medical Center, Rotterdam, Netherlands.,Center for Biomics, Erasmus Medical Center, Rotterdam, Netherlands
| | - Juhi Shah
- Department of Medicine, The Research Institute of the McGill University Health Centre, McGill University, Montreal, QC, Canada
| | - Tomas Ozdian
- Faculty of Medicine and Dentistry, Institute of Molecular and Translational Medicine, Palacký University, Olomouc, Czechia
| | - Jie Liao
- Department of Physiology, CF Translational Research Centre, McGill University, Montreal, QC, Canada
| | - Carolina Martini
- Department of Physiology, CF Translational Research Centre, McGill University, Montreal, QC, Canada
| | - Danuta Radzioch
- Department of Medicine, The Research Institute of the McGill University Health Centre, McGill University, Montreal, QC, Canada
| | - John W Hanrahan
- Department of Medicine, The Research Institute of the McGill University Health Centre, McGill University, Montreal, QC, Canada.,Department of Physiology, CF Translational Research Centre, McGill University, Montreal, QC, Canada
| | - Bob J Scholte
- Cell Biology Department, Erasmus Medical Center, Rotterdam, Netherlands.,Pediatric Pulmonology, Sophia Children's Hospital, Erasmus Medical Center, Rotterdam, Netherlands
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14
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Turner MJ, Dauletbaev N, Lands LC, Hanrahan JW. The Phosphodiesterase Inhibitor Ensifentrine Reduces Production of Proinflammatory Mediators in Well Differentiated Bronchial Epithelial Cells by Inhibiting PDE4. J Pharmacol Exp Ther 2020; 375:414-429. [PMID: 33012706 DOI: 10.1124/jpet.120.000080] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Accepted: 09/24/2020] [Indexed: 12/15/2022] Open
Abstract
Cystic fibrosis (CF) is caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) anion channel that impair airway salt and fluid secretion. Excessive release of proinflammatory cytokines and chemokines by CF bronchial epithelium during airway infection leads to chronic inflammation and a slow decline in lung function; thus, there is much interest in finding safe and effective treatments that reduce inflammation in CF. We showed previously that the cyclic nucleotide phosphodiesterase (PDE) inhibitor ensifentrine (RPL554; Verona Pharma) stimulates the channel function of CFTR mutants with abnormal gating and also those with defective trafficking that are partially rescued using a clinically approved corrector drug. PDE inhibitors also have known anti-inflammatory effects; therefore, we examined whether ensifentrine alters the production of proinflammatory cytokines in CF bronchial epithelial cells. Ensifentrine reduced the production of monocyte chemoattractant protein-1 and granulocyte monocyte colony-stimulating factor (GM-CSF) during challenge with interleukin-1β Comparing the effect of ensifentrine with milrinone and roflumilast, selective PDE3 and PDE4 inhibitors, respectively, demonstrated that the anti-inflammatory effect of ensifentrine was mainly due to inhibition of PDE4. Beneficial modulation of GM-CSF was further enhanced when ensifentrine was combined with low concentrations of the β 2-adrenergic agonist isoproterenol or the corticosteroid dexamethasone. The results indicate that ensifentrine may have beneficial anti-inflammatory effects in CF airways particularly when used in combination with β 2-adrenergic agonists or corticosteroids. SIGNIFICANCE STATEMENT: Airway inflammation that is disproportionate to the burden of chronic airway infection causes much of the pathology in the cystic fibrosis (CF) lung. We show here that ensifentrine beneficially modulates the release of proinflammatory factors in well differentiated CF bronchial epithelial cells that is further enhanced when combined with β2-adrenergic agonists or low-concentration corticosteroids. The results encourage further clinical testing of ensifentrine, alone and in combination with β2-adrenergic agonists or low-concentration corticosteroids, as a novel anti-inflammatory therapy for CF.
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Affiliation(s)
- Mark J Turner
- Departments of Physiology (M.J.T., J.W.H.) and Pediatrics (N.D.) and Cystic Fibrosis Translational Research Centre (M.J.T., L.C.L., J.W.H), McGill University, Montréal, Québec, Canada; Pediatric Respiratory Medicine, Montreal Children's Hospital, Montréal, Québec, Canada (N.D., L.C.L.); Research Institute - McGill University Health Centre, Montréal, Québec, Canada (L.C.L., J.W.H.); Department of Internal, Respiratory Translational Laboratory, Respiratory and Critical Care Medicine, Philipps-University of Marburg, Marburg, Germany (N.D.); and Faculty of Medicine and Healthcare, al-Farabi Kazakh National University, Almaty, Kazakhstan (N.D.)
| | - Nurlan Dauletbaev
- Departments of Physiology (M.J.T., J.W.H.) and Pediatrics (N.D.) and Cystic Fibrosis Translational Research Centre (M.J.T., L.C.L., J.W.H), McGill University, Montréal, Québec, Canada; Pediatric Respiratory Medicine, Montreal Children's Hospital, Montréal, Québec, Canada (N.D., L.C.L.); Research Institute - McGill University Health Centre, Montréal, Québec, Canada (L.C.L., J.W.H.); Department of Internal, Respiratory Translational Laboratory, Respiratory and Critical Care Medicine, Philipps-University of Marburg, Marburg, Germany (N.D.); and Faculty of Medicine and Healthcare, al-Farabi Kazakh National University, Almaty, Kazakhstan (N.D.)
| | - Larry C Lands
- Departments of Physiology (M.J.T., J.W.H.) and Pediatrics (N.D.) and Cystic Fibrosis Translational Research Centre (M.J.T., L.C.L., J.W.H), McGill University, Montréal, Québec, Canada; Pediatric Respiratory Medicine, Montreal Children's Hospital, Montréal, Québec, Canada (N.D., L.C.L.); Research Institute - McGill University Health Centre, Montréal, Québec, Canada (L.C.L., J.W.H.); Department of Internal, Respiratory Translational Laboratory, Respiratory and Critical Care Medicine, Philipps-University of Marburg, Marburg, Germany (N.D.); and Faculty of Medicine and Healthcare, al-Farabi Kazakh National University, Almaty, Kazakhstan (N.D.)
| | - John W Hanrahan
- Departments of Physiology (M.J.T., J.W.H.) and Pediatrics (N.D.) and Cystic Fibrosis Translational Research Centre (M.J.T., L.C.L., J.W.H), McGill University, Montréal, Québec, Canada; Pediatric Respiratory Medicine, Montreal Children's Hospital, Montréal, Québec, Canada (N.D., L.C.L.); Research Institute - McGill University Health Centre, Montréal, Québec, Canada (L.C.L., J.W.H.); Department of Internal, Respiratory Translational Laboratory, Respiratory and Critical Care Medicine, Philipps-University of Marburg, Marburg, Germany (N.D.); and Faculty of Medicine and Healthcare, al-Farabi Kazakh National University, Almaty, Kazakhstan (N.D.)
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15
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Turner MJ, Luo Y, Thomas DY, Hanrahan JW. The dual phosphodiesterase 3/4 inhibitor RPL554 stimulates rare class III and IV CFTR mutants. Am J Physiol Lung Cell Mol Physiol 2020; 318:L908-L920. [PMID: 32159371 DOI: 10.1152/ajplung.00285.2019] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Over 2,000 mutations have been reported in the cystic fibrosis transmembrane conductance regulator (cftr) gene, many of which cause disease but are rare and have no effective treatment. Thus, there is an unmet need for new, mutation-agnostic therapies for cystic fibrosis (CF). Phosphodiesterase (PDE) inhibitors are one such class of therapeutics that have been shown to elevate intracellular cAMP levels and stimulate CFTR-dependent anion secretion in human airway epithelia; however, the number of people with CF that could be helped by PDE inhibitors remains to be determined. Here we used Fisher rat thyroid (FRT) cells stably transduced with rare human CFTR mutants and studied their responsiveness to the dual phosphodiesterase 3/4 inhibitor RPL554 (Verona Pharma). Through its inhibitory effect on PDE4D, we find that RPL554 can elevate intracellular cAMP leading to a potentiation of forskolin-stimulated current mediated by R334W, T338I, G551D, and S549R mutants of CFTR when used alone or in combination with CFTR modulators. We also were able to reproduce these effects of RPL554 on G551D-CFTR when it was expressed in primary human bronchial epithelial cells, indicating that RPL554 would have stimulatory effects on rare CFTR mutants in human airways and validating FRT cells as a model for PDE inhibitor studies. Furthermore, we provide biochemical evidence that VX-809 causes surprisingly robust correction of several class III and IV CFTR mutants. Together, our findings further support the therapeutic potential of RPL554 for patients with CF with class III/IV mutations and emphasize the potential of PDEs as potential drug targets that could benefit patients with CF.
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Affiliation(s)
- Mark J Turner
- Department of Physiology, McGill University, Montreal, Quebec, Canada.,Cystic Fibrosis Translational Research Centre, McGill University, Montreal, Quebec, Canada
| | - Yishan Luo
- Department of Physiology, McGill University, Montreal, Quebec, Canada.,Cystic Fibrosis Translational Research Centre, McGill University, Montreal, Quebec, Canada
| | - David Y Thomas
- Cystic Fibrosis Translational Research Centre, McGill University, Montreal, Quebec, Canada.,Department of Biochemistry, McGill University, Montreal, Quebec, Canada
| | - John W Hanrahan
- Department of Physiology, McGill University, Montreal, Quebec, Canada.,Cystic Fibrosis Translational Research Centre, McGill University, Montreal, Quebec, Canada
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16
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Kim D, Huang J, Billet A, Abu-Arish A, Goepp J, Matthes E, Tewfik MA, Frenkiel S, Hanrahan JW. Pendrin Mediates Bicarbonate Secretion and Enhances Cystic Fibrosis Transmembrane Conductance Regulator Function in Airway Surface Epithelia. Am J Respir Cell Mol Biol 2020; 60:705-716. [PMID: 30742493 DOI: 10.1165/rcmb.2018-0158oc] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Bicarbonate facilitates mucin unpacking and bacterial killing; however, its transport mechanisms in the airways are not well understood. cAMP stimulates anion efflux through the cystic fibrosis (CF) transmembrane conductance regulator (CFTR; ABCC7) anion channel, and this is defective in CF. The anion exchanger pendrin (SLC26A4) also mediates HCO3- efflux and is upregulated by proinflammatory cytokines. Here, we examined pendrin and CFTR expression and their contributions to HCO3- secretion by human nasal and bronchial epithelia. In native tissue, both proteins were most abundant at the apical pole of ciliated surface cells with little expression in submucosal glands. In well-differentiated primary nasal and bronchial cell cultures, IL-4 dramatically increased pendrin mRNA levels and apical immunostaining. Exposure to low-Cl- apical solution caused intracellular alkalinization (ΔpHi) that was enhanced fourfold by IL-4 pretreatment. ΔpHi was unaffected by 4,4'-diisothiocyano-2,2'-stilbenedisulfonic acid (DIDS) or CFTR inhibitor CFTRinh-172, but was reduced by adenoviral shRNA targeting pendrin. Forskolin increased ΔpHi, and this stimulation was prevented by CFTRinh-172, implicating CFTR, yet forskolin only increased ΔpHi after pendrin expression had been induced by IL-4. The dependence of ΔpHi on pendrin suggests there is minimal electrical coupling between Cl- and HCO3- fluxes and that CFTR activation increases anion exchange-mediated HCO3- influx. Conversely, inducing pendrin expression increased forskolin-stimulated, CFTRinh-172-sensitive current by approximately twofold in epithelial and nonepithelial cells. We conclude that pendrin mediates most HCO3- secretion across airway surface epithelium during inflammation and enhances electrogenic Cl- secretion via CFTR, as described for other SLC26A transporters.
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Affiliation(s)
- Dusik Kim
- 1 Department of Physiology and.,2 Cystic Fibrosis Translational Research Centre, McGill University, Montréal, Québec, Canada; and
| | - Junwei Huang
- 1 Department of Physiology and.,2 Cystic Fibrosis Translational Research Centre, McGill University, Montréal, Québec, Canada; and
| | - Arnaud Billet
- 1 Department of Physiology and.,2 Cystic Fibrosis Translational Research Centre, McGill University, Montréal, Québec, Canada; and
| | - Asmahan Abu-Arish
- 1 Department of Physiology and.,2 Cystic Fibrosis Translational Research Centre, McGill University, Montréal, Québec, Canada; and
| | - Julie Goepp
- 1 Department of Physiology and.,2 Cystic Fibrosis Translational Research Centre, McGill University, Montréal, Québec, Canada; and
| | - Elizabeth Matthes
- 1 Department of Physiology and.,2 Cystic Fibrosis Translational Research Centre, McGill University, Montréal, Québec, Canada; and
| | - Marc A Tewfik
- 2 Cystic Fibrosis Translational Research Centre, McGill University, Montréal, Québec, Canada; and.,3 Department of Otolaryngology-Head and Neck Surgery and
| | - Saul Frenkiel
- 2 Cystic Fibrosis Translational Research Centre, McGill University, Montréal, Québec, Canada; and.,3 Department of Otolaryngology-Head and Neck Surgery and
| | - John W Hanrahan
- 1 Department of Physiology and.,2 Cystic Fibrosis Translational Research Centre, McGill University, Montréal, Québec, Canada; and.,4 Research Institute, McGill University Health Centre, Montréal, Québec, Canada
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17
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Mustafina KR, Sato Y, Hanrahan JW, Wiseman PW. STED Superresolution Imaging of DUOX1 and CEN2 Reveals Substructure of Membrane Macromolecular Complexes in Human Bronchial Epithelial Cells. Biophys J 2020. [DOI: 10.1016/j.bpj.2019.11.928] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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18
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Poroca DR, Amer N, Li A, Hanrahan JW, Chappe VM. Changes in the R-region interactions depend on phosphorylation and contribute to PKA and PKC regulation of the cystic fibrosis transmembrane conductance regulator chloride channel. FASEB Bioadv 2020; 2:33-48. [PMID: 32123855 PMCID: PMC6996395 DOI: 10.1096/fba.2019-00053] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Accepted: 11/19/2019] [Indexed: 01/30/2023] Open
Abstract
The CFTR chloride channel is regulated by phosphorylation at PKA and PKC consensus sites within its regulatory region (R-region) through a mechanism, which is still not completely understood. We used a split-CFTR construct expressing the N-term-TMD1-NBD1 (Front Half; FH), TMD2-NBD2-C-Term (Back Half; BH), and the R-region as separate polypeptides (Split-R) in BHK cells, to investigate in situ how different phosphorylation conditions affect the R-region interactions with other parts of the protein. In proximity ligation assays, we studied the formation of complexes between the R-region and each half of the Split-CFTR. We found that at basal conditions, the density of complexes formed between the R-region and both halves of the split channel were equal. PKC stimulation alone had no effect, whereas PKA stimulation induced the formation of more complexes between the R-region and both halves compared to basal conditions. Moreover, PKC + PKA stimulation further enhanced the formation of FH-R complexes by 40% from PKA level. In cells expressing the Split-R with the two inhibitory PKC sites on the R-region inactivated (SR-S641A/T682A), density of FH-R complexes was much higher than in Split-R WT expressing cells after PKC or PKC + PKA stimulation. No differences were observed for BH-R complexes measured at all phosphorylation conditions. Since full-length CFTR channels display large functional responses to PKC + PKA in WT and S641A/T682A mutant, we conclude that FH-R interactions are important for CFTR function. Inactivation of consensus PKC site serine 686 (S686A) significantly reduced the basal BH-R interaction and prevented the PKC enhancing effect on CFTR function and FH-R interaction. The phospho-mimetic mutation (S686D) restored basal BH-R interaction and the PKC enhancing effect on CFTR function with enhanced FH-R interaction. As the channel function is mainly stimulated by PKA phosphorylation of the R-region, and this response is known to be enhanced by PKC phosphorylation, our data support a model in which the regulation of CFTR activation results from increased interactions of the R-region with the N-term-TMD1-NBD1. Also, serine S686 was found to be critical for the PKC enhancing effect which requires a permissive BH-R interaction at basal level and increased FH-R interaction after PKC + PKA phosphorylation.
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Affiliation(s)
- Diogo R. Poroca
- Department of Physiology & BiophysicsDalhousie UniversityHalifaxNSCanada
| | - Noha Amer
- Department of Physiology & BiophysicsDalhousie UniversityHalifaxNSCanada
| | - Audrey Li
- Department of Physiology & BiophysicsDalhousie UniversityHalifaxNSCanada
| | | | - Valerie M. Chappe
- Department of Physiology & BiophysicsDalhousie UniversityHalifaxNSCanada
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19
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Sato Y, Thomas DY, Hanrahan JW. The anion transporter SLC26A9 localizes to tight junctions and is degraded by the proteasome when co-expressed with F508del-CFTR. J Biol Chem 2019; 294:18269-18284. [PMID: 31645438 PMCID: PMC6885613 DOI: 10.1074/jbc.ra119.010192] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Revised: 10/21/2019] [Indexed: 01/05/2023] Open
Abstract
Mutations in the gene encoding the cystic fibrosis transmembrane conductance regulator (CFTR) disrupt epithelial secretion and cause cystic fibrosis (CF). Available CFTR modulators provide only modest clinical benefits, so alternative therapeutic targets are being explored. The anion-conducting transporter solute carrier family 26 member 9 (SLC26A9) is a promising candidate, but its functional expression is drastically reduced in cells that express the most common CF-associated CFTR variant, F508del-CFTR, through mechanisms that remain incompletely understood. Here, we examined the metabolic stability and location of SLC26A9 and its relationship to CFTR. Compared with SLC26A9 levels in BHK cells expressing SLC26A9 alone or with WT-CFTR, co-expression of SLC26A9 with F508del-CFTR reduced total and plasma membrane levels of SLC26A9. Proteasome inhibitors increased SLC26A9 immunofluorescence in primary human bronchial epithelial cells (pHBEs) homozygous for F508del-CFTR but not in non-CF pHBEs, suggesting that F508del-CFTR enhances proteasomal SLC26A9 degradation. Apical SLC26A9 expression increased when F508del-CFTR trafficking was partially corrected by low temperature or with the CFTR modulator VX-809. The immature glycoforms of SLC26A9 and CFTR co-immunoprecipitated, consistent with their interaction in the endoplasmic reticulum (ER). Transfection with increasing amounts of WT-CFTR cDNA progressively increased SLC26A9 levels in F508del-CFTR-expressing cells, suggesting that WT-CFTR competes with F508del-CFTR for SLC26A9 binding. Immunofluorescence staining of endogenous SLC26A9 and transfection of a 3HA-tagged construct into well-differentiated cells revealed that SLC26A9 is mostly present at tight junctions. We conclude that SLC26A9 interacts with CFTR in both the ER and Golgi and that its interaction with F508del-CFTR increases proteasomal SLC26A9 degradation.
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Affiliation(s)
- Yukiko Sato
- Department of Physiology, McGill University, Montréal, Québec H3G 1Y6, Canada; Cystic Fibrosis Translational Research Center, McGill University, Montréal, Québec H3G 1Y6, Canada
| | - David Y Thomas
- Cystic Fibrosis Translational Research Center, McGill University, Montréal, Québec H3G 1Y6, Canada; Department of Biochemistry, McGill University, Montréal, Québec H3A 1A3, Canada
| | - John W Hanrahan
- Department of Physiology, McGill University, Montréal, Québec H3G 1Y6, Canada; Cystic Fibrosis Translational Research Center, McGill University, Montréal, Québec H3G 1Y6, Canada.
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20
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Garić D, De Sanctis JB, Dumut DC, Shah J, Peña MJ, Youssef M, Petrof BJ, Kopriva F, Hanrahan JW, Hajduch M, Radzioch D. Fenretinide favorably affects mucins (MUC5AC/MUC5B) and fatty acid imbalance in a manner mimicking CFTR-induced correction. Biochim Biophys Acta Mol Cell Biol Lipids 2019; 1865:158538. [PMID: 31678518 DOI: 10.1016/j.bbalip.2019.158538] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2019] [Revised: 09/28/2019] [Accepted: 10/03/2019] [Indexed: 02/07/2023]
Abstract
Cystic fibrosis (CF) is the most common genetic disease in Caucasians. CF is manifested by abnormal accumulation of mucus in the lungs, which serves as fertile ground for the growth of microorganisms leading to recurrent infections and ultimately, lung failure. Mucus in CF patients consists of DNA from dead neutrophils as well as mucins produced by goblet cells. MUC5AC mucin leads to pathological plugging of the airways whereas MUC5B has a protective role against bacterial infection. Therefore, decreasing the level of MUC5AC while maintaining MUC5B intact would in principle be a desirable mucoregulatory treatment outcome. Fenretinide prevented the lipopolysaccharide-induced increase of MUC5AC gene expression, without affecting the level of MUC5B, in a lung goblet cell line. Additionally, fenretinide treatment reversed the pro-inflammatory imbalance of fatty acids by increasing docosahexaenoic acid and decreasing the levels of arachidonic acid in a lung epithelial cell line and primary leukocytes derived from CF patients. Furthermore, for the first time we also demonstrate the effect of fenretinide on multiple unsaturated fatty acids, as well as differential effects on the levels of long- compared to very-long-chain saturated fatty acids which are important substrates of complex phospholipids. Finally, we demonstrate that pre-treating mice with fenretinide in a chronic model of P. aeruginosa lung infection efficiently decreases the accumulation of mucus. These findings suggest that fenretinide may offer a new approach to therapeutic modulation of pathological mucus production in CF.
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Affiliation(s)
- Dušan Garić
- Department of Human Genetics, McGill University, Montreal, Quebec, Canada; Program in Infectious Diseases and Immunity in Global Health, McGill University Health Center, Montreal, Quebec, Canada
| | - Juan B De Sanctis
- Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacky University, Olomouc, Czech Republic; Institute of Immunology, Faculty of Medicine, Universidad Central de Venezuela, Bolivarian Republic of Venezuela
| | - Daciana Catalina Dumut
- Department of Medicine, Division of Experimental Medicine, McGill University, Montreal, Quebec, Canada; Program in Infectious Diseases and Immunity in Global Health, McGill University Health Center, Montreal, Quebec, Canada
| | - Juhi Shah
- Department of Pharmacology and Therapeutics, McGill University, Montreal, Quebec, Canada; Program in Infectious Diseases and Immunity in Global Health, McGill University Health Center, Montreal, Quebec, Canada
| | - Maria Johanna Peña
- Institute of Immunology, Faculty of Medicine, Universidad Central de Venezuela, Bolivarian Republic of Venezuela
| | - Mina Youssef
- Department of Human Genetics, McGill University, Montreal, Quebec, Canada; Program in Infectious Diseases and Immunity in Global Health, McGill University Health Center, Montreal, Quebec, Canada
| | - Basil J Petrof
- Meakins-Christie Laboratories, Translational Research in Respiratory Diseases Program, Department of Medicine, McGill University Health Centre, Montreal, Quebec, Canada
| | - Francisek Kopriva
- Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacky University, Olomouc, Czech Republic
| | - John W Hanrahan
- Department of Biochemistry, McGill University, Montreal, Quebec, Canada
| | - Marian Hajduch
- Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacky University, Olomouc, Czech Republic
| | - Danuta Radzioch
- Department of Human Genetics, McGill University, Montreal, Quebec, Canada; Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacky University, Olomouc, Czech Republic; Department of Medicine, Division of Experimental Medicine, McGill University, Montreal, Quebec, Canada; Program in Infectious Diseases and Immunity in Global Health, McGill University Health Center, Montreal, Quebec, Canada.
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21
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Chandrasekaran A, Kouthouridis S, Lee W, Lin N, Ma Z, Turner MJ, Hanrahan JW, Moraes C. Magnetic microboats for floating, stiffness tunable, air-liquid interface epithelial cultures. Lab Chip 2019; 19:2786-2798. [PMID: 31332423 DOI: 10.1039/c9lc00267g] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
To study respiratory diseases, in vitro airway epithelial models are commonly implemented by culturing airway cells on a porous surface at an air-liquid interface (ALI). However, these surfaces are often supraphysiologically stiff, which is known to affect the organization, maturation, and responses of cells to potential therapies in other biological culture models. While it is possible to culture cells on soft hydrogel substrates at an air-liquid interface, these techniques are challenging to implement particularly in high-throughput applications which require robust and repetitive material handling procedures. To address these two limitations and characterize epithelial cultures on substrates of varying stiffness at the ALI, we developed a novel "lung-on-a-boat", in which stiffness-tuneable hydrogels are integrated into the bottoms of polymeric microstructures, which normally float at the air-liquid interface. An embedded magnetic material can be used to sink the boat on demand when a magnetic field is applied, enabling reliable transition between submerged and ALI culture. In this work, we prototype a functional ALI microboat platform, with integrated stiffness-tunable polyacrylamide hydrogel surfaces, and validate the use of this technology with a model epithelial cell line. We verify sufficient transport through the hydrogel base to maintain cell viability and stimulate cultures, using a model nanoparticle with known toxicity. We then demonstrate significant morphological and functional effects on epithelial barrier formation, suggesting that substrate stiffness is an important parameter to consider in the design of in vitro epithelial ALI models for drug discovery and fundamental research.
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Affiliation(s)
| | - Sonya Kouthouridis
- Department of Chemical Engineering, McGill University, Montreal, Canada.
| | - Wontae Lee
- Department of Chemical Engineering, McGill University, Montreal, Canada.
| | - Nicholas Lin
- Department of Chemical Engineering, McGill University, Montreal, Canada.
| | - Zhenwei Ma
- Department of Chemical Engineering, McGill University, Montreal, Canada.
| | - Mark J Turner
- Department of Physiology, McGill University, Montreal, QC, Canada
| | - John W Hanrahan
- Department of Physiology, McGill University, Montreal, QC, Canada and Cystic Fibrosis Translational Research Center, McGill University, Montreal, Canada
| | - Christopher Moraes
- Department of Chemical Engineering, McGill University, Montreal, Canada. and Cystic Fibrosis Translational Research Center, McGill University, Montreal, Canada and Department of Biological and Biomedical Engineering, McGill University, Montreal, Canada and Goodman Cancer Research Center, McGill University, Montreal, Canada
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Kim Chiaw P, Hantouche C, Wong MJH, Matthes E, Robert R, Hanrahan JW, Shrier A, Young JC. Hsp70 and DNAJA2 limit CFTR levels through degradation. PLoS One 2019; 14:e0220984. [PMID: 31408507 PMCID: PMC6692068 DOI: 10.1371/journal.pone.0220984] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2019] [Accepted: 07/26/2019] [Indexed: 11/18/2022] Open
Abstract
Cystic Fibrosis is caused by mutations in the CFTR anion channel, many of which cause its misfolding and degradation. CFTR folding depends on the Hsc70 and Hsp70 chaperones and their co-chaperone DNAJA1, but Hsc70/Hsp70 is also involved in CFTR degradation. Here, we address how these opposing functions are balanced. DNAJA2 and DNAJA1 were both important for CFTR folding, however overexpressing DNAJA2 but not DNAJA1 enhanced CFTR degradation at the endoplasmic reticulum by Hsc70/Hsp70 and the E3 ubiquitin ligase CHIP. Excess Hsp70 also promoted CFTR degradation, but this occurred through the lysosomal pathway and required CHIP but not complex formation with HOP and Hsp90. Notably, the Hsp70 inhibitor MKT077 enhanced levels of mature CFTR and the most common disease variant ΔF508-CFTR, by slowing turnover and allowing delayed maturation, respectively. MKT077 also boosted the channel activity of ΔF508-CFTR when combined with the corrector compound VX809. Thus, the Hsp70 system is the major determinant of CFTR degradation, and its modulation can partially relieve the misfolding phenotype.
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Affiliation(s)
- Patrick Kim Chiaw
- Department of Biochemistry, McGill University, Montreal, Quebec, Canada
- Groupe de Recherche Axé sur la Structure des Protéines, McGill University, Montreal, Quebec, Canada
| | - Christine Hantouche
- Groupe de Recherche Axé sur la Structure des Protéines, McGill University, Montreal, Quebec, Canada
- Department of Physiology, McGill University, Montreal, Quebec, Canada
| | - Michael J. H. Wong
- Department of Biochemistry, McGill University, Montreal, Quebec, Canada
- Groupe de Recherche Axé sur la Structure des Protéines, McGill University, Montreal, Quebec, Canada
| | - Elizabeth Matthes
- Groupe de Recherche Axé sur la Structure des Protéines, McGill University, Montreal, Quebec, Canada
- Department of Physiology, McGill University, Montreal, Quebec, Canada
| | - Renaud Robert
- Groupe de Recherche Axé sur la Structure des Protéines, McGill University, Montreal, Quebec, Canada
- Department of Physiology, McGill University, Montreal, Quebec, Canada
| | - John W. Hanrahan
- Groupe de Recherche Axé sur la Structure des Protéines, McGill University, Montreal, Quebec, Canada
- Department of Physiology, McGill University, Montreal, Quebec, Canada
| | - Alvin Shrier
- Groupe de Recherche Axé sur la Structure des Protéines, McGill University, Montreal, Quebec, Canada
- Department of Physiology, McGill University, Montreal, Quebec, Canada
| | - Jason C. Young
- Department of Biochemistry, McGill University, Montreal, Quebec, Canada
- Groupe de Recherche Axé sur la Structure des Protéines, McGill University, Montreal, Quebec, Canada
- * E-mail:
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23
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Hanrahan JW, Sato Y, Carlile GW, Jansen G, Young JC, Thomas DY. Cystic Fibrosis: Proteostatic correctors of CFTR trafficking and alternative therapeutic targets. Expert Opin Ther Targets 2019; 23:711-724. [PMID: 31169041 DOI: 10.1080/14728222.2019.1628948] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Introduction: Cystic fibrosis (CF) is the most frequent lethal orphan disease and is caused by mutations in the CFTR gene. The most frequent mutation F508del-CFTR affects multiple organs; infections and subsequent infections and complications in the lung lead to death. Areas covered: This review focuses on new targets and mechanisms that are attracting interest for the development of CF therapies. The F508del-CFTR protein is retained in the endoplasmic reticulum (ER) but has some function if it can traffic to the plasma membrane. Cell-based assays have been used to screen chemical libraries for small molecule correctors that restore its trafficking. Pharmacological chaperones are correctors that bind directly to the F508del-CFTR mutant and promote its folding and trafficking. Other correctors fall into a heterogeneous class of proteostasis modulators that act indirectly by altering cellular homeostasis. Expert opinion: Pharmacological chaperones have so far been the most successful correctors of F508del-CFTR trafficking, but their level of correction means that more than one corrector is required. Proteostasis modulators have low levels of correction but hold promise because some can correct several different CFTR mutations. Identification of their cellular targets and the potential for development may lead to new therapies for CF.
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Affiliation(s)
- John W Hanrahan
- a Department of Physiology , McGill University , Montréal , QC , Canada.,c Research Institute of the McGill University Health Centre , McGill University , Montréal , QC , Canada
| | - Yukiko Sato
- a Department of Physiology , McGill University , Montréal , QC , Canada.,b Cystic Fibrosis Translational Research centre , McGill University , Montréal , QC , Canada
| | - Graeme W Carlile
- b Cystic Fibrosis Translational Research centre , McGill University , Montréal , QC , Canada.,d Department of Biochemistry , McGill University , Montréal , QC , Canada
| | - Gregor Jansen
- d Department of Biochemistry , McGill University , Montréal , QC , Canada
| | - Jason C Young
- b Cystic Fibrosis Translational Research centre , McGill University , Montréal , QC , Canada.,d Department of Biochemistry , McGill University , Montréal , QC , Canada
| | - David Y Thomas
- b Cystic Fibrosis Translational Research centre , McGill University , Montréal , QC , Canada.,d Department of Biochemistry , McGill University , Montréal , QC , Canada.,e Department of Human Genetics , McGill University , Montréal , QC , Canada
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24
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Abu-Arish A, Pandžić E, Kim D, Tseng HW, Wiseman PW, Hanrahan JW. Agonists that stimulate secretion promote the recruitment of CFTR into membrane lipid microdomains. J Gen Physiol 2019; 151:834-849. [PMID: 31048413 PMCID: PMC6572005 DOI: 10.1085/jgp.201812143] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2018] [Accepted: 04/05/2019] [Indexed: 01/20/2023] Open
Abstract
The cystic fibrosis transmembrane conductance regulator (CFTR) is a tightly regulated anion channel that mediates secretion by epithelia and is mutated in the disease cystic fibrosis. CFTR forms macromolecular complexes with many proteins; however, little is known regarding its associations with membrane lipids or the regulation of its distribution and mobility at the cell surface. We report here that secretagogues (agonists that stimulate secretion) such as the peptide hormone vasoactive intestinal peptide (VIP) and muscarinic agonist carbachol increase CFTR aggregation into cholesterol-dependent clusters, reduce CFTR lateral mobility within and between membrane microdomains, and trigger the fusion of clusters into large (3.0 µm2) ceramide-rich platforms. CFTR clusters are closely associated with motile cilia and with the enzyme acid sphingomyelinase (ASMase) that is constitutively bound on the cell surface. Platform induction is prevented by pretreating cells with cholesterol oxidase to disrupt lipid rafts or by exposure to the ASMase functional inhibitor amitriptyline or the membrane-impermeant reducing agent 2-mercaptoethanesulfonate. Platforms are reversible, and their induction does not lead to an increase in apoptosis; however, blocking platform formation does prevent the increase in CFTR surface expression that normally occurs during VIP stimulation. These results demonstrate that CFTR is colocalized with motile cilia and reveal surprisingly robust regulation of CFTR distribution and lateral mobility, most likely through autocrine redox activation of extracellular ASMase. Formation of ceramide-rich platforms containing CFTR enhances transepithelial secretion and likely has other functions related to inflammation and mucosal immunity.
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Affiliation(s)
- Asmahan Abu-Arish
- Department of Physiology, McGill University, Montréal, Canada
- Department of Physics, McGill University, Montréal, Canada
- Cystic Fibrosis Translational Research Centre, McGill University, Montréal, Canada
| | - Elvis Pandžić
- Department of Physics, McGill University, Montréal, Canada
| | - Dusik Kim
- Department of Physiology, McGill University, Montréal, Canada
- Cystic Fibrosis Translational Research Centre, McGill University, Montréal, Canada
| | - Hsin Wei Tseng
- Department of Physiology, McGill University, Montréal, Canada
| | - Paul W Wiseman
- Department of Physics, McGill University, Montréal, Canada
- Department of Chemistry, McGill University, Montréal, Canada
- Cystic Fibrosis Translational Research Centre, McGill University, Montréal, Canada
| | - John W Hanrahan
- Department of Physiology, McGill University, Montréal, Canada
- Cystic Fibrosis Translational Research Centre, McGill University, Montréal, Canada
- McGill University Health Centre Research Institute, Montréal, Canada
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25
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Kim D, Huang J, Billet A, Abu‐Arish A, Goepp J, Matthes E, Tewfik MA, Frenkiel S, Hanrahan JW. Pendrin Mediates Bicarbonate Secretion and Enhances CFTR Function in Airway Surface Epithelia. FASEB J 2019. [DOI: 10.1096/fasebj.2019.33.1_supplement.544.16] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Dusik Kim
- PhysiologyMcGill UniversityMontrealQCCanada
- CF Translational Research centreMcGill UniversityMontrealQCCanada
| | | | | | | | | | | | - Marc A. Tewfik
- Otolaryngology‐Head and Neck SurgeryMcGill UniversityMontrealQCCanada
| | - Saul Frenkiel
- Otolaryngology‐Head and Neck SurgeryMcGill UniversityMontrealQCCanada
| | - John W. Hanrahan
- PhysiologyMcGill UniversityMontrealQCCanada
- Research Institute‐McGill University Health CentreMontrealQCCanada
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26
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Matthes E, Goepp J, Martini C, Shan J, Liao J, Thomas DY, Hanrahan JW. Variable Responses to CFTR Correctors in vitro: Estimating the Design Effect in Precision Medicine. Front Pharmacol 2018; 9:1490. [PMID: 30618775 PMCID: PMC6305743 DOI: 10.3389/fphar.2018.01490] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Accepted: 12/05/2018] [Indexed: 12/19/2022] Open
Abstract
Interest in precision medicine has grown in recent years due to the variable clinical benefit provided by some medications, their cost, and by new opportunities to tailor therapies to individual patients. In cystic fibrosis it may soon be possible to test several corrector drugs that improve the folding and functional expression of mutant cystic fibrosis transmembrane conductance regulator (CFTR) prospectively using cells from a patient to find the one that is best for that individual. Patient-to-patient variation in cell culture responses to correctors and the reproducibility of those responses has not been studied quantitatively. We measured the functional correction provided by lumacaftor (VX-809) using bronchial epithelial cells from 20 patients homozygous for the F508del-CFTR mutation. Significant differences were observed between individuals, supporting the utility of prospective testing. However, when correction of F508del-CFTR was measured repeatedly using cell aliquots from the same individuals, a design effect was observed that would impact statistical tests of significance. The results suggest that the sample size obtained from power calculations should be increased to compensate for group sampling when CFTR corrector drugs are compared in vitro for precision medicine.
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Affiliation(s)
- Elizabeth Matthes
- Department of Physiology, McGill University, Montréal, QC, Canada
- Cystic Fibrosis Translational Research Centre, McGill University, Montréal, QC, Canada
| | - Julie Goepp
- Department of Physiology, McGill University, Montréal, QC, Canada
- Cystic Fibrosis Translational Research Centre, McGill University, Montréal, QC, Canada
| | - Carolina Martini
- Department of Physiology, McGill University, Montréal, QC, Canada
- Cystic Fibrosis Translational Research Centre, McGill University, Montréal, QC, Canada
| | - Jiajie Shan
- Department of Physiology, McGill University, Montréal, QC, Canada
- Cystic Fibrosis Translational Research Centre, McGill University, Montréal, QC, Canada
| | - Jie Liao
- Department of Physiology, McGill University, Montréal, QC, Canada
- Cystic Fibrosis Translational Research Centre, McGill University, Montréal, QC, Canada
| | - David Y. Thomas
- Cystic Fibrosis Translational Research Centre, McGill University, Montréal, QC, Canada
- Department of Biochemistry, McGill University, Montréal, QC, Canada
| | - John W. Hanrahan
- Department of Physiology, McGill University, Montréal, QC, Canada
- Cystic Fibrosis Translational Research Centre, McGill University, Montréal, QC, Canada
- Research Institute of the McGill University Health Centre, McGill University, Montréal, QC, Canada
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27
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Carlile GW, Yang Q, Matthes E, Liao J, Radinovic S, Miyamoto C, Robert R, Hanrahan JW, Thomas DY. A novel triple combination of pharmacological chaperones improves F508del-CFTR correction. Sci Rep 2018; 8:11404. [PMID: 30061653 PMCID: PMC6065411 DOI: 10.1038/s41598-018-29276-y] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Accepted: 07/09/2018] [Indexed: 12/29/2022] Open
Abstract
Pharmacological chaperones (e.g. VX-809, lumacaftor) that bind directly to F508del-CFTR and correct its mislocalization are promising therapeutics for Cystic Fibrosis (CF). However to date, individual correctors provide only ~4% improvement in lung function measured as FEV1, suggesting that multiple drugs will be needed to achieve substantial clinical benefit. Here we examine if multiple sites for pharmacological chaperones exist and can be targeted to enhance the rescue of F508del-CFTR with the premise that additive or synergistic rescue by multiple pharmacological chaperones compared to single correctors indicates that they have different sites of action. First, we found that a combination of the pharmacological chaperones VX-809 and RDR1 provide additive correction of F508del-CFTR. Then using cellular thermal stability assays (CETSA) we demonstrated the possibility of a third pharmacologically important site using the novel pharmacological chaperone tool compound 4-methyl-N-[3-(morpholin-4-yl) quinoxalin-2-yl] benzenesulfonamide (MCG1516A). All three pharmacological chaperones appear to interact with the first nucleotide-binding domain (NBD1). The triple combination of MCG1516A, RDR1, and VX-809 restored CFTR function to >20% that of non-CF cells in well differentiated HBE cells and to much higher levels in other cell types. Thus the results suggest the presence of at least three distinct sites for pharmacological chaperones on F508del-CFTR NBD1, encouraging the development of triple corrector combinations.
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Affiliation(s)
- Graeme W Carlile
- Cystic Fibrosis Translational Research Center, Department of Biochemistry McGill University Montreal Quebec Canada, H3G 1Y6, Montreal, Quebec, Canada.
| | - Qi Yang
- Cystic Fibrosis Translational Research Center, Department of Biochemistry McGill University Montreal Quebec Canada, H3G 1Y6, Montreal, Quebec, Canada
| | - Elizabeth Matthes
- Cystic Fibrosis Translational Research Center, Department of Physiology McGill University Montreal Quebec Canada, H3G 1Y6, Montreal, Quebec, Canada
| | - Jie Liao
- Cystic Fibrosis Translational Research Center, Department of Physiology McGill University Montreal Quebec Canada, H3G 1Y6, Montreal, Quebec, Canada
| | - Stevo Radinovic
- Cystic Fibrosis Translational Research Center, Department of Biochemistry McGill University Montreal Quebec Canada, H3G 1Y6, Montreal, Quebec, Canada.,National Research Council, Biotechnology Research Institute, 6100 Royalmount Ave, H4P 2R2, Montreal, Quebec, Canada
| | - Carol Miyamoto
- Cystic Fibrosis Translational Research Center, Department of Biochemistry McGill University Montreal Quebec Canada, H3G 1Y6, Montreal, Quebec, Canada
| | - Renaud Robert
- Cystic Fibrosis Translational Research Center, Department of Physiology McGill University Montreal Quebec Canada, H3G 1Y6, Montreal, Quebec, Canada
| | - John W Hanrahan
- Cystic Fibrosis Translational Research Center, Department of Physiology McGill University Montreal Quebec Canada, H3G 1Y6, Montreal, Quebec, Canada
| | - David Y Thomas
- Cystic Fibrosis Translational Research Center, Department of Biochemistry McGill University Montreal Quebec Canada, H3G 1Y6, Montreal, Quebec, Canada
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28
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Pandžić E, Abu-Arish A, Whan RM, Hanrahan JW, Wiseman PW. Velocity landscape correlation resolves multiple flowing protein populations from fluorescence image time series. Methods 2018; 140-141:126-139. [DOI: 10.1016/j.ymeth.2018.02.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Revised: 12/06/2017] [Accepted: 02/12/2018] [Indexed: 11/16/2022] Open
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29
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Huang J, Kim D, Shan J, Abu‐Arish A, Luo Y, Hanrahan JW. Most bicarbonate secretion by Calu-3 cells is mediated by CFTR and independent of pendrin. Physiol Rep 2018; 6:e13641. [PMID: 29536650 PMCID: PMC5849580 DOI: 10.14814/phy2.13641] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2018] [Revised: 02/10/2018] [Accepted: 02/12/2018] [Indexed: 11/24/2022] Open
Abstract
Bicarbonate plays an important role in airway host defense, however, its transport mechanisms remain uncertain. Here we examined the relative contributions of the anion channel CFTR (cystic fibrosis transmembrane conductance regulator, ABCC7) and the anion exchanger pendrin (SLC26A4) to HCO3- secretion by the human airway cell line Calu-3. Pendrin and CFTR were both detected in parental Calu-3 cells, although mRNA and protein expression appeared higher for CFTR than for pendrin. Targeting pendrin transcripts with lentiviral shRNA reduced pendrin detection by immunofluorescence staining but did not alter the rates of HCO3- or fluid secretion, HCO3- transport under pH-stat conditions, or net HCO3- flux across basolaterally permeabilized monolayers. Intracellular pH varied with step changes in apical Cl- and HCO3- concentrations in control and pendrin knockdown Calu-3 cells, but not in CFTR deficient cells. Exposure to the proinflammatory cytokine IL-4, which strongly upregulates pendrin expression in airway surface epithelia, had little effect on Calu-3 pendrin expression and did not alter fluid or HCO3- secretion. Similar results were obtained using air-liquid interface and submerged cultures, although CFTR and pendrin mRNA expression were both lower when cells were cultured under submerged conditions. While the conclusions cannot be extrapolated to other airway epithelia, the present results demonstrate that most HCO3- secretion by Calu-3 cells is mediated by CFTR.
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Affiliation(s)
- Junwei Huang
- Department of PhysiologyMcGill UniversityMontréalQuébecCanada
- Cystic Fibrosis Translational Research CenterMcGill UniversityMontréalQuébecCanada
- Present address:
AbbVie Bioresearch CenterAbbVie Inc.381 Plantation St.WorcesterMA01605
| | - Dusik Kim
- Department of PhysiologyMcGill UniversityMontréalQuébecCanada
- Cystic Fibrosis Translational Research CenterMcGill UniversityMontréalQuébecCanada
| | - Jiajie Shan
- Department of PhysiologyMcGill UniversityMontréalQuébecCanada
- Cystic Fibrosis Translational Research CenterMcGill UniversityMontréalQuébecCanada
- Present address:
School of MedicineSouth China University of TechnologyGuangzhou University TownPanyu DistrictGuangzhouChina
| | - Asmahan Abu‐Arish
- Department of PhysiologyMcGill UniversityMontréalQuébecCanada
- Cystic Fibrosis Translational Research CenterMcGill UniversityMontréalQuébecCanada
| | - Yishan Luo
- Department of PhysiologyMcGill UniversityMontréalQuébecCanada
- Cystic Fibrosis Translational Research CenterMcGill UniversityMontréalQuébecCanada
| | - John W. Hanrahan
- Department of PhysiologyMcGill UniversityMontréalQuébecCanada
- Cystic Fibrosis Translational Research CenterMcGill UniversityMontréalQuébecCanada
- Research Institute‐McGill University Health CentreMontréalQuébecCanada
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Wong FH, AbuArish A, Matthes E, Turner MJ, Greene LE, Cloutier A, Robert R, Thomas DY, Cosa G, Cantin AM, Hanrahan JW. Cigarette smoke activates CFTR through ROS-stimulated cAMP signaling in human bronchial epithelial cells. Am J Physiol Cell Physiol 2018; 314:C118-C134. [PMID: 28978522 PMCID: PMC5866379 DOI: 10.1152/ajpcell.00099.2017] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Revised: 09/27/2017] [Accepted: 09/27/2017] [Indexed: 11/22/2022]
Abstract
Air pollution stimulates airway epithelial secretion through a cholinergic reflex that is unaffected in cystic fibrosis (CF), yet a strong correlation is observed between passive smoke exposure in the home and impaired lung function in CF children. Our aim was to study the effects of low smoke concentrations on cystic fibrosis transmembrane conductance regulator (CFTR) function in vitro. Cigarette smoke extract stimulated robust anion secretion that was transient, mediated by CFTR, and dependent on cAMP-dependent protein kinase activation. Secretion was initiated by reactive oxygen species (ROS) and mediated by at least two distinct pathways: autocrine activation of EP4 prostanoid receptors and stimulation of Ca2+ store-operated cAMP signaling. The response was absent in cells expressing the most common disease-causing mutant F508del-CFTR. In addition to the initial secretion, prolonged exposure of non-CF bronchial epithelial cells to low levels of smoke also caused a gradual decline in CFTR functional expression. F508del-CFTR channels that had been rescued by the CF drug combination VX-809 (lumacaftor) + VX-770 (ivacaftor) were more sensitive to this downregulation than wild-type CFTR. The results suggest that CFTR-mediated secretion during acute cigarette smoke exposure initially protects the airway epithelium while prolonged exposure reduces CFTR functional expression and reduces the efficacy of CF drugs.
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Affiliation(s)
- Francis H Wong
- Department of Physiology, McGill University , Montreal, Quebec , Canada
- Cystic Fibrosis Translational Research Centre, McGill University , Montreal, Quebec , Canada
| | - Asmahan AbuArish
- Department of Physiology, McGill University , Montreal, Quebec , Canada
- Cystic Fibrosis Translational Research Centre, McGill University , Montreal, Quebec , Canada
| | - Elizabeth Matthes
- Department of Physiology, McGill University , Montreal, Quebec , Canada
- Cystic Fibrosis Translational Research Centre, McGill University , Montreal, Quebec , Canada
| | - Mark J Turner
- Department of Physiology, McGill University , Montreal, Quebec , Canada
- Cystic Fibrosis Translational Research Centre, McGill University , Montreal, Quebec , Canada
| | - Lana E Greene
- Department of Chemistry, McGill University , Montreal, Quebec , Canada
| | - Alexandre Cloutier
- Pulmonary Division, Faculty of Medicine, Université de Sherbrooke , Sherbrooke, Quebec , Canada
| | - Renaud Robert
- Department of Physiology, McGill University , Montreal, Quebec , Canada
- Cystic Fibrosis Translational Research Centre, McGill University , Montreal, Quebec , Canada
- Department of Biochemistry, McGill University , Montreal, Quebec , Canada
| | - David Y Thomas
- Cystic Fibrosis Translational Research Centre, McGill University , Montreal, Quebec , Canada
- Department of Biochemistry, McGill University , Montreal, Quebec , Canada
| | - Gonzalo Cosa
- Department of Chemistry, McGill University , Montreal, Quebec , Canada
| | - André M Cantin
- Cystic Fibrosis Translational Research Centre, McGill University , Montreal, Quebec , Canada
- Pulmonary Division, Faculty of Medicine, Université de Sherbrooke , Sherbrooke, Quebec , Canada
| | - John W Hanrahan
- Department of Physiology, McGill University , Montreal, Quebec , Canada
- Cystic Fibrosis Translational Research Centre, McGill University , Montreal, Quebec , Canada
- Research Institute of McGill Univ. Hospital Centre , Montreal, Quebec , Canada
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Hanrahan JW, Matthes E, Carlile G, Thomas DY. Corrector combination therapies for F508del-CFTR. Curr Opin Pharmacol 2017; 34:105-111. [PMID: 29080476 DOI: 10.1016/j.coph.2017.09.016] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Revised: 09/18/2017] [Accepted: 09/26/2017] [Indexed: 10/18/2022]
Abstract
These are exciting times in the development of therapeutics for cystic fibrosis (CF). New correctors and potentiators of the cystic fibrosis transmembrane conductance regulator (CFTR) are being developed in academic laboratories and pharmaceutical companies, and the field is just beginning to understand their mechanisms of action. Studies of CFTR modulators are also yielding insight into the general principles and strategies that can be used when developing pharmacological chaperones, a new class of drugs. Combining two or even three correctors with a potentiator is an especially promising approach which should lead to further improvements in efficacy and clinical benefit for patients.
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Affiliation(s)
- John W Hanrahan
- Department of Physiology, McGill University, Montréal, Québec H3G 1Y6, Canada; CF Translational Research Centre, McGill University, Canada; Research Institute of the McGill University Hospital Centre, Canada.
| | - Elizabeth Matthes
- Department of Physiology, McGill University, Montréal, Québec H3G 1Y6, Canada; CF Translational Research Centre, McGill University, Canada
| | - Graeme Carlile
- CF Translational Research Centre, McGill University, Canada; Department of Biochemistry, McGill University, Canada
| | - David Y Thomas
- CF Translational Research Centre, McGill University, Canada; Department of Biochemistry, McGill University, Canada
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Garić D, De Sanctis JB, Wojewodka G, Houle D, Cupri S, Abu-Arish A, Hanrahan JW, Hajduch M, Matouk E, Radzioch D. Fenretinide differentially modulates the levels of long- and very long-chain ceramides by downregulating Cers5 enzyme: evidence from bench to bedside. J Mol Med (Berl) 2017; 95:1053-1064. [DOI: 10.1007/s00109-017-1564-y] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2016] [Revised: 05/01/2017] [Accepted: 06/15/2017] [Indexed: 10/19/2022]
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Billet A, Froux L, Hanrahan JW, Becq F. Development of Automated Patch Clamp Technique to Investigate CFTR Chloride Channel Function. Front Pharmacol 2017; 8:195. [PMID: 28439239 PMCID: PMC5383655 DOI: 10.3389/fphar.2017.00195] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Accepted: 03/24/2017] [Indexed: 11/13/2022] Open
Abstract
The chloride (Cl-) channel cystic fibrosis transmembrane conductance regulator (CFTR) is defective in cystic fibrosis (CF), and mutation of its encoding gene leads to various defects such as retention of the misfolded protein in the endoplasmic reticulum, reduced stability at the plasma membrane, abnormal channel gating with low open probability, and thermal instability, which leads to inactivation of the channel at physiological temperature. Pharmacotherapy is one major therapeutic approach in the CF field and needs sensible and fast tools to identify promising compounds. The high throughput screening assays available are often fast and sensible techniques but with lack of specificity. Few works used automated patch clamp (APC) for CFTR recording, and none have compared conventional and planar techniques and demonstrated their capabilities for different types of experiments. In this study, we evaluated the use of planar parallel APC technique for pharmacological search of CFTR-trafficking correctors and CFTR function modulators. Using optimized conditions, we recorded both wt- and corrected F508del-CFTR Cl- currents with automated whole-cell patch clamp and compared the data to results obtained with conventional manual whole-cell patch clamp. We found no significant difference in patch clamp parameters such as cell capacitance and series resistance between automated and manual patch clamp. Also, the results showed good similarities of CFTR currents recording between the two methods. We showed that similar stimulation protocols could be used in both manual and automatic techniques allowing precise control of temperature, classic I/V relationship, and monitoring of current stability in time. In conclusion, parallel patch-clamp recording allows rapid and efficient investigation of CFTR currents with a variety of tests available and could be considered as new tool for medium throughput screening in CF pharmacotherapy.
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Affiliation(s)
- Arnaud Billet
- Laboratoire Signalisation et Transports Ioniques Membranaires, Université de Poitiers - ERL7368, Centre National de la Recherche ScientifiquePoitiers, France
| | - Lionel Froux
- Laboratoire Signalisation et Transports Ioniques Membranaires, Université de Poitiers - ERL7368, Centre National de la Recherche ScientifiquePoitiers, France
| | - John W Hanrahan
- Department of Physiology, McGill University, MontrealQC, Canada.,McGill Cystic Fibrosis Translational Research Centre, MontrealQC, Canada.,The Research Institute of the McGill University Health Centre, MontrealQC, Canada
| | - Frederic Becq
- Laboratoire Signalisation et Transports Ioniques Membranaires, Université de Poitiers - ERL7368, Centre National de la Recherche ScientifiquePoitiers, France
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Vijftigschild LAW, Berkers G, Dekkers JF, Zomer-van Ommen DD, Matthes E, Kruisselbrink E, Vonk A, Hensen CE, Heida-Michel S, Geerdink M, Janssens HM, van de Graaf EA, Bronsveld I, de Winter-de Groot KM, Majoor CJ, Heijerman HGM, de Jonge HR, Hanrahan JW, van der Ent CK, Beekman JM. β2-Adrenergic receptor agonists activate CFTR in intestinal organoids and subjects with cystic fibrosis. Eur Respir J 2016; 48:768-79. [PMID: 27471203 DOI: 10.1183/13993003.01661-2015] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2015] [Accepted: 05/11/2016] [Indexed: 01/12/2023]
Abstract
We hypothesized that people with cystic fibrosis (CF) who express CFTR (cystic fibrosis transmembrane conductance regulator) gene mutations associated with residual function may benefit from G-protein coupled receptor (GPCR)-targeting drugs that can activate and enhance CFTR function.We used intestinal organoids to screen a GPCR-modulating compound library and identified β2-adrenergic receptor agonists as the most potent inducers of CFTR function.β2-Agonist-induced organoid swelling correlated with the CFTR genotype, and could be induced in homozygous CFTR-F508del organoids and highly differentiated primary CF airway epithelial cells after rescue of CFTR trafficking by small molecules. The in vivo response to treatment with an oral or inhaled β2-agonist (salbutamol) in CF patients with residual CFTR function was evaluated in a pilot study. 10 subjects with a R117H or A455E mutation were included and showed changes in the nasal potential difference measurement after treatment with oral salbutamol, including a significant improvement of the baseline potential difference of the nasal mucosa (+6.35 mV, p<0.05), suggesting that this treatment might be effective in vivo Furthermore, plasma that was collected after oral salbutamol treatment induced CFTR activation when administered ex vivo to organoids.This proof-of-concept study suggests that organoids can be used to identify drugs that activate CFTR function in vivo and to select route of administration.
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Affiliation(s)
- Lodewijk A W Vijftigschild
- Dept of Pediatric Pulmonology, University Medical Center, Utrecht, The Netherlands Laboratory of Translational Immunology, University Medical Center, Utrecht, The Netherlands These two authors contributed equally to this work
| | - Gitte Berkers
- Dept of Pediatric Pulmonology, University Medical Center, Utrecht, The Netherlands These two authors contributed equally to this work
| | - Johanna F Dekkers
- Dept of Pediatric Pulmonology, University Medical Center, Utrecht, The Netherlands Laboratory of Translational Immunology, University Medical Center, Utrecht, The Netherlands These two authors contributed equally to this work
| | - Domenique D Zomer-van Ommen
- Dept of Pediatric Pulmonology, University Medical Center, Utrecht, The Netherlands Laboratory of Translational Immunology, University Medical Center, Utrecht, The Netherlands These two authors contributed equally to this work
| | - Elizabeth Matthes
- CF Translational Research Centre, Dept of Physiology, McGill University, Montréal, QC, Canada
| | - Evelien Kruisselbrink
- Dept of Pediatric Pulmonology, University Medical Center, Utrecht, The Netherlands Laboratory of Translational Immunology, University Medical Center, Utrecht, The Netherlands
| | - Annelotte Vonk
- Dept of Pediatric Pulmonology, University Medical Center, Utrecht, The Netherlands Laboratory of Translational Immunology, University Medical Center, Utrecht, The Netherlands
| | - Chantal E Hensen
- Dept of Pediatric Pulmonology, University Medical Center, Utrecht, The Netherlands
| | - Sabine Heida-Michel
- Dept of Pediatric Pulmonology, University Medical Center, Utrecht, The Netherlands
| | - Margot Geerdink
- Dept of Pediatric Pulmonology, University Medical Center, Utrecht, The Netherlands
| | - Hettie M Janssens
- Dept of Pediatric Pulmonology, Erasmus Medical Center/Sophia Children's Hospital, Rotterdam, The Netherlands
| | | | - Inez Bronsveld
- Dept of Pulmonology, University Medical Center, Utrecht, The Netherlands
| | | | - Christof J Majoor
- Dept of Respiratory Medicine, Academic Medical Center, Amsterdam, The Netherlands
| | - Harry G M Heijerman
- Dept of Pulmonology and Cystic Fibrosis, Haga Teaching Hospital, The Hague, The Netherlands
| | - Hugo R de Jonge
- Dept of Gastroenterology and Hepatology, Erasmus University Medical Center, Rotterdam, The Netherlands
| | - John W Hanrahan
- CF Translational Research Centre, Dept of Physiology, McGill University, Montréal, QC, Canada
| | | | - Jeffrey M Beekman
- Dept of Pediatric Pulmonology, University Medical Center, Utrecht, The Netherlands Regenerative Medicine Center Utrecht, University Medical Center, Utrecht, The Netherlands
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Carlile GW, Robert R, Matthes E, Yang Q, Solari R, Hatley R, Edge CM, Hanrahan JW, Andersen R, Thomas DY, Birault V. Latonduine Analogs Restore F508del-Cystic Fibrosis Transmembrane Conductance Regulator Trafficking through the Modulation of Poly-ADP Ribose Polymerase 3 and Poly-ADP Ribose Polymerase 16 Activity. Mol Pharmacol 2016; 90:65-79. [PMID: 27193581 DOI: 10.1124/mol.115.102418] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2015] [Accepted: 05/17/2016] [Indexed: 01/02/2023] Open
Abstract
Cystic fibrosis (CF) is a major lethal genetic disease caused by mutations in the CF transmembrane conductance regulator gene (CFTR). This encodes a chloride ion channel on the apical surface of epithelial cells. The most common mutation in CFTR (F508del-CFTR) generates a protein that is misfolded and retained in the endoplasmic reticulum. Identifying small molecules that correct this CFTR trafficking defect is a promising approach in CF therapy. However, to date only modest efficacy has been reported for correctors in clinical trials. We identified the marine sponge metabolite latonduine as a corrector. We have now developed a series of latonduine derivatives that are more potent F508del-CFTR correctors with one (MCG315 [2,3-dihydro-1H-2-benzazepin-1-one]) having 10-fold increased corrector activity and an EC50 of 72.25 nM. We show that the latonduine analogs inhibit poly-ADP ribose polymerase (PARP) isozymes 1, 3, and 16. Further our molecular modeling studies point to the latonduine analogs binding to the PARP nicotinamide-binding domain. We established the relationship between the ability of the latonduine analogs to inhibit PARP-16 and their ability to correct F508del-CFTR trafficking. We show that latonduine can inhibit both PARP-3 and -16 and that this is necessary for CFTR correction. We demonstrate that latonduine triggers correction by regulating the activity of the unfolded protein response activator inositol-requiring enzyme (IRE-1) via modulation of the level of its ribosylation by PARP-16. These results establish latonduines novel site of action as well as its proteostatic mechanism of action.
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Affiliation(s)
- Graeme W Carlile
- Department of Biochemistry (G.W.C., R.R., Q.Y., D.Y.T.), Cystic Fibrosis Translational Research Center (G.W.C., R.R., E.M., Q.Y., J.W.H., D.Y.T.), and Department of Physiology (E.M., J.W.H.), McGill University, Montréal, Québec, Canada; GSK Respiratory Therapeutic Area Unit (R.S., R.H., V.B.), and R&D Platform Technology and Science (C.M.E.), GlaxoSmithKline Medicines Research Centre, Stevenage, Hertfordshire, United Kingdom; Departments of Chemistry and Earth, Ocean and Atmospheric Sciences, University of British Columbia, Vancouver, British Columbia, Canada (R.A.); Faculty of Medicine National Heart and Lung Institute, Imperial College London, London, United Kingdom (R.S.); Francis Crick Institute, London, United Kingdom (V.B.)
| | - Renaud Robert
- Department of Biochemistry (G.W.C., R.R., Q.Y., D.Y.T.), Cystic Fibrosis Translational Research Center (G.W.C., R.R., E.M., Q.Y., J.W.H., D.Y.T.), and Department of Physiology (E.M., J.W.H.), McGill University, Montréal, Québec, Canada; GSK Respiratory Therapeutic Area Unit (R.S., R.H., V.B.), and R&D Platform Technology and Science (C.M.E.), GlaxoSmithKline Medicines Research Centre, Stevenage, Hertfordshire, United Kingdom; Departments of Chemistry and Earth, Ocean and Atmospheric Sciences, University of British Columbia, Vancouver, British Columbia, Canada (R.A.); Faculty of Medicine National Heart and Lung Institute, Imperial College London, London, United Kingdom (R.S.); Francis Crick Institute, London, United Kingdom (V.B.)
| | - Elizabeth Matthes
- Department of Biochemistry (G.W.C., R.R., Q.Y., D.Y.T.), Cystic Fibrosis Translational Research Center (G.W.C., R.R., E.M., Q.Y., J.W.H., D.Y.T.), and Department of Physiology (E.M., J.W.H.), McGill University, Montréal, Québec, Canada; GSK Respiratory Therapeutic Area Unit (R.S., R.H., V.B.), and R&D Platform Technology and Science (C.M.E.), GlaxoSmithKline Medicines Research Centre, Stevenage, Hertfordshire, United Kingdom; Departments of Chemistry and Earth, Ocean and Atmospheric Sciences, University of British Columbia, Vancouver, British Columbia, Canada (R.A.); Faculty of Medicine National Heart and Lung Institute, Imperial College London, London, United Kingdom (R.S.); Francis Crick Institute, London, United Kingdom (V.B.)
| | - Qi Yang
- Department of Biochemistry (G.W.C., R.R., Q.Y., D.Y.T.), Cystic Fibrosis Translational Research Center (G.W.C., R.R., E.M., Q.Y., J.W.H., D.Y.T.), and Department of Physiology (E.M., J.W.H.), McGill University, Montréal, Québec, Canada; GSK Respiratory Therapeutic Area Unit (R.S., R.H., V.B.), and R&D Platform Technology and Science (C.M.E.), GlaxoSmithKline Medicines Research Centre, Stevenage, Hertfordshire, United Kingdom; Departments of Chemistry and Earth, Ocean and Atmospheric Sciences, University of British Columbia, Vancouver, British Columbia, Canada (R.A.); Faculty of Medicine National Heart and Lung Institute, Imperial College London, London, United Kingdom (R.S.); Francis Crick Institute, London, United Kingdom (V.B.)
| | - Roberto Solari
- Department of Biochemistry (G.W.C., R.R., Q.Y., D.Y.T.), Cystic Fibrosis Translational Research Center (G.W.C., R.R., E.M., Q.Y., J.W.H., D.Y.T.), and Department of Physiology (E.M., J.W.H.), McGill University, Montréal, Québec, Canada; GSK Respiratory Therapeutic Area Unit (R.S., R.H., V.B.), and R&D Platform Technology and Science (C.M.E.), GlaxoSmithKline Medicines Research Centre, Stevenage, Hertfordshire, United Kingdom; Departments of Chemistry and Earth, Ocean and Atmospheric Sciences, University of British Columbia, Vancouver, British Columbia, Canada (R.A.); Faculty of Medicine National Heart and Lung Institute, Imperial College London, London, United Kingdom (R.S.); Francis Crick Institute, London, United Kingdom (V.B.)
| | - Richard Hatley
- Department of Biochemistry (G.W.C., R.R., Q.Y., D.Y.T.), Cystic Fibrosis Translational Research Center (G.W.C., R.R., E.M., Q.Y., J.W.H., D.Y.T.), and Department of Physiology (E.M., J.W.H.), McGill University, Montréal, Québec, Canada; GSK Respiratory Therapeutic Area Unit (R.S., R.H., V.B.), and R&D Platform Technology and Science (C.M.E.), GlaxoSmithKline Medicines Research Centre, Stevenage, Hertfordshire, United Kingdom; Departments of Chemistry and Earth, Ocean and Atmospheric Sciences, University of British Columbia, Vancouver, British Columbia, Canada (R.A.); Faculty of Medicine National Heart and Lung Institute, Imperial College London, London, United Kingdom (R.S.); Francis Crick Institute, London, United Kingdom (V.B.)
| | - Colin M Edge
- Department of Biochemistry (G.W.C., R.R., Q.Y., D.Y.T.), Cystic Fibrosis Translational Research Center (G.W.C., R.R., E.M., Q.Y., J.W.H., D.Y.T.), and Department of Physiology (E.M., J.W.H.), McGill University, Montréal, Québec, Canada; GSK Respiratory Therapeutic Area Unit (R.S., R.H., V.B.), and R&D Platform Technology and Science (C.M.E.), GlaxoSmithKline Medicines Research Centre, Stevenage, Hertfordshire, United Kingdom; Departments of Chemistry and Earth, Ocean and Atmospheric Sciences, University of British Columbia, Vancouver, British Columbia, Canada (R.A.); Faculty of Medicine National Heart and Lung Institute, Imperial College London, London, United Kingdom (R.S.); Francis Crick Institute, London, United Kingdom (V.B.)
| | - John W Hanrahan
- Department of Biochemistry (G.W.C., R.R., Q.Y., D.Y.T.), Cystic Fibrosis Translational Research Center (G.W.C., R.R., E.M., Q.Y., J.W.H., D.Y.T.), and Department of Physiology (E.M., J.W.H.), McGill University, Montréal, Québec, Canada; GSK Respiratory Therapeutic Area Unit (R.S., R.H., V.B.), and R&D Platform Technology and Science (C.M.E.), GlaxoSmithKline Medicines Research Centre, Stevenage, Hertfordshire, United Kingdom; Departments of Chemistry and Earth, Ocean and Atmospheric Sciences, University of British Columbia, Vancouver, British Columbia, Canada (R.A.); Faculty of Medicine National Heart and Lung Institute, Imperial College London, London, United Kingdom (R.S.); Francis Crick Institute, London, United Kingdom (V.B.)
| | - Raymond Andersen
- Department of Biochemistry (G.W.C., R.R., Q.Y., D.Y.T.), Cystic Fibrosis Translational Research Center (G.W.C., R.R., E.M., Q.Y., J.W.H., D.Y.T.), and Department of Physiology (E.M., J.W.H.), McGill University, Montréal, Québec, Canada; GSK Respiratory Therapeutic Area Unit (R.S., R.H., V.B.), and R&D Platform Technology and Science (C.M.E.), GlaxoSmithKline Medicines Research Centre, Stevenage, Hertfordshire, United Kingdom; Departments of Chemistry and Earth, Ocean and Atmospheric Sciences, University of British Columbia, Vancouver, British Columbia, Canada (R.A.); Faculty of Medicine National Heart and Lung Institute, Imperial College London, London, United Kingdom (R.S.); Francis Crick Institute, London, United Kingdom (V.B.)
| | - David Y Thomas
- Department of Biochemistry (G.W.C., R.R., Q.Y., D.Y.T.), Cystic Fibrosis Translational Research Center (G.W.C., R.R., E.M., Q.Y., J.W.H., D.Y.T.), and Department of Physiology (E.M., J.W.H.), McGill University, Montréal, Québec, Canada; GSK Respiratory Therapeutic Area Unit (R.S., R.H., V.B.), and R&D Platform Technology and Science (C.M.E.), GlaxoSmithKline Medicines Research Centre, Stevenage, Hertfordshire, United Kingdom; Departments of Chemistry and Earth, Ocean and Atmospheric Sciences, University of British Columbia, Vancouver, British Columbia, Canada (R.A.); Faculty of Medicine National Heart and Lung Institute, Imperial College London, London, United Kingdom (R.S.); Francis Crick Institute, London, United Kingdom (V.B.)
| | - Véronique Birault
- Department of Biochemistry (G.W.C., R.R., Q.Y., D.Y.T.), Cystic Fibrosis Translational Research Center (G.W.C., R.R., E.M., Q.Y., J.W.H., D.Y.T.), and Department of Physiology (E.M., J.W.H.), McGill University, Montréal, Québec, Canada; GSK Respiratory Therapeutic Area Unit (R.S., R.H., V.B.), and R&D Platform Technology and Science (C.M.E.), GlaxoSmithKline Medicines Research Centre, Stevenage, Hertfordshire, United Kingdom; Departments of Chemistry and Earth, Ocean and Atmospheric Sciences, University of British Columbia, Vancouver, British Columbia, Canada (R.A.); Faculty of Medicine National Heart and Lung Institute, Imperial College London, London, United Kingdom (R.S.); Francis Crick Institute, London, United Kingdom (V.B.)
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Abu-Arish A, Pandzic E, Goepp J, Matthes E, Hanrahan JW, Wiseman PW. Cholesterol modulates CFTR confinement in the plasma membrane of primary epithelial cells. Biophys J 2016; 109:85-94. [PMID: 26153705 DOI: 10.1016/j.bpj.2015.04.042] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2015] [Accepted: 04/23/2015] [Indexed: 01/01/2023] Open
Abstract
The cystic fibrosis transmembrane conductance regulator (CFTR) is a plasma-membrane anion channel that, when mutated, causes the disease cystic fibrosis. Although CFTR has been detected in a detergent-resistant membrane fraction prepared from airway epithelial cells, suggesting that it may partition into cholesterol-rich membrane microdomains (lipid rafts), its compartmentalization has not been demonstrated in intact cells and the influence of microdomains on CFTR lateral mobility is unknown. We used live-cell imaging, spatial image correlation spectroscopy, and k-space image correlation spectroscopy to examine the aggregation state of CFTR and its dynamics both within and outside microdomains in the plasma membrane of primary human bronchial epithelial cells. These studies were also performed during treatments that augment or deplete membrane cholesterol. We found two populations of CFTR molecules that were distinguishable based on their dynamics at the cell surface. One population showed confinement and had slow dynamics that were highly cholesterol dependent. The other, more abundant population was less confined and diffused more rapidly. Treatments that deplete the membrane of cholesterol caused the confined fraction and average number of CFTR molecules per cluster to decrease. Elevating cholesterol had the opposite effect, increasing channel aggregation and the fraction of channels displaying confinement, consistent with CFTR recruitment into cholesterol-rich microdomains with dimensions below the optical resolution limit. Viral infection caused the nanoscale microdomains to fuse into large platforms and reduced CFTR mobility. To our knowledge, these results provide the first biophysical evidence for multiple CFTR populations and have implications for regulation of their surface expression and channel function.
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Affiliation(s)
| | - Elvis Pandzic
- Physics, McGill University, Montreal, Quebec, Canada
| | - Julie Goepp
- Physiology, McGill University, Montreal, Quebec, Canada
| | | | | | - Paul W Wiseman
- Chemistry & Physics, McGill University, Montreal, Quebec, Canada.
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Wiseman PW, Desjardins JF, Abuarish A, Hanrahan JW. Mapping CFTR Clusters in 3D via Single Molecule Step Photobleaching Analysis in Epithelial Cells. Biophys J 2016. [DOI: 10.1016/j.bpj.2015.11.2588] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Matthes E, Goepp J, Carlile GW, Luo Y, Dejgaard K, Billet A, Robert R, Thomas DY, Hanrahan JW. Low free drug concentration prevents inhibition of F508del CFTR functional expression by the potentiator VX-770 (ivacaftor). Br J Pharmacol 2016; 173:459-70. [PMID: 26492939 DOI: 10.1111/bph.13365] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2015] [Revised: 07/22/2015] [Accepted: 10/12/2015] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND AND PURPOSE The most common cystic fibrosis (CF) mutation F508del inhibits the gating and surface expression of CFTR, a plasma membrane anion channel. Optimal pharmacotherapies will probably require both a 'potentiator' to increase channel open probability and a 'corrector' that improves folding and trafficking of the mutant protein and its stability at the cell surface. Interaction between CF drugs has been reported but remains poorly understood. EXPERIMENTAL APPROACH CF bronchial epithelial cells were exposed to the corrector VX-809 (lumacaftor) and potentiator VX-770 (ivacaftor) individually or in combination. Functional expression of CFTR was assayed as the forskolin-stimulated short-circuit current (Isc ) across airway epithelial monolayers expressing F508del CFTR. KEY RESULTS The potentiated Isc response during forskolin stimulation was increased sixfold after pretreatment with VX-809 alone and reached ~11% that measured across non-CF monolayers. VX-770 (100 nM) and genistein (50 μM) caused similar levels of potentiation, which were not additive and were abolished by the CFTR inhibitor CFTRinh -172. The unbound fraction of VX-770 in plasma was 0.13 ± 0.04%, which together with previous measurements in patients given 250 mg p.o. twice daily, suggests a peak free plasma concentration of 1.5-8.5 nM. Chronic exposure to high VX-770 concentrations (>1 μM) inhibited functional correction by VX-809 but not in the presence of physiological protein levels (20-40 mg·mL(-1) ). Chronic exposure to a low concentration of VX-770 (100 nM) together with VX-809 (1 μM) also did not reduce the forskolin-stimulated Isc , relative to cells chronically exposed to VX-809 alone, provided it was assayed acutely using the same, clinically relevant concentration of potentiator. CONCLUSIONS AND IMPLICATIONS Chronic exposure to clinically relevant concentrations of VX-770 did not reduce F508del CFTR function. Therapeutic benefit of VX-770 + VX-809 (Orkambi) is probably limited by the efficacy of VX-809 rather than by inhibition by VX-770.
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Affiliation(s)
- Elizabeth Matthes
- Department of Physiology, McGill University, Montréal, QC, Canada.,CF Translational Research Centre, McGill University, Montréal, QC, Canada
| | - Julie Goepp
- Department of Physiology, McGill University, Montréal, QC, Canada.,CF Translational Research Centre, McGill University, Montréal, QC, Canada
| | - Graeme W Carlile
- CF Translational Research Centre, McGill University, Montréal, QC, Canada.,Department of Biochemistry, McGill University, Montréal, QC, Canada
| | - Yishan Luo
- Department of Physiology, McGill University, Montréal, QC, Canada.,CF Translational Research Centre, McGill University, Montréal, QC, Canada
| | - Kurt Dejgaard
- Department of Biochemistry, McGill University, Montréal, QC, Canada
| | - Arnaud Billet
- Department of Physiology, McGill University, Montréal, QC, Canada.,CF Translational Research Centre, McGill University, Montréal, QC, Canada
| | - Renaud Robert
- Department of Physiology, McGill University, Montréal, QC, Canada.,CF Translational Research Centre, McGill University, Montréal, QC, Canada
| | - David Y Thomas
- CF Translational Research Centre, McGill University, Montréal, QC, Canada.,Department of Biochemistry, McGill University, Montréal, QC, Canada
| | - John W Hanrahan
- Department of Physiology, McGill University, Montréal, QC, Canada.,CF Translational Research Centre, McGill University, Montréal, QC, Canada.,Research Institute of the McGill University Health Centre, Montréal, QC, Canada
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Abstract
The CFTR chloride channel is tightly regulated by phosphorylation at multiple serine residues. Recently it has been proposed that its activity is also regulated by tyrosine kinases, however the tyrosine phosphorylation sites remain to be identified. In this study we examined 2 candidate tyrosine residues near the boundary between the first nucleotide binding domain and the R domain, a region which is important for channel function but devoid of PKA consensus sequences. Mutating tyrosines at positions 625 and 627 dramatically reduced responses to Src or Pyk2 without altering the activation by PKA, suggesting they may contribute to CFTR regulation.
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Affiliation(s)
- Arnaud Billet
- a Department of Physiology , McGill University , Montreal , Quebec , Canada.,b CF Translational Research Center, McGill University , Montreal , Quebec , Canada
| | - Yanlin Jia
- a Department of Physiology , McGill University , Montreal , Quebec , Canada.,b CF Translational Research Center, McGill University , Montreal , Quebec , Canada
| | - Timothy J Jensen
- c Department of Biochemistry and Biophysics & CF Research Center , UNC Chapel Hill, Chapel Hill , NC , USA
| | - Yue-Xian Hou
- c Department of Biochemistry and Biophysics & CF Research Center , UNC Chapel Hill, Chapel Hill , NC , USA
| | - Xiu-Bao Chang
- c Department of Biochemistry and Biophysics & CF Research Center , UNC Chapel Hill, Chapel Hill , NC , USA
| | - John R Riordan
- c Department of Biochemistry and Biophysics & CF Research Center , UNC Chapel Hill, Chapel Hill , NC , USA
| | - John W Hanrahan
- a Department of Physiology , McGill University , Montreal , Quebec , Canada.,b CF Translational Research Center, McGill University , Montreal , Quebec , Canada.,d Research Institute of the McGill University Hospital Center , Montréal , Quebec , Canada
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Turner MJ, Matthes E, Billet A, Ferguson AJ, Thomas DY, Randell SH, Ostrowski LE, Abbott-Banner K, Hanrahan JW. The dual phosphodiesterase 3 and 4 inhibitor RPL554 stimulates CFTR and ciliary beating in primary cultures of bronchial epithelia. Am J Physiol Lung Cell Mol Physiol 2015; 310:L59-70. [PMID: 26545902 DOI: 10.1152/ajplung.00324.2015] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2015] [Accepted: 10/30/2015] [Indexed: 11/22/2022] Open
Abstract
Cystic fibrosis (CF), a genetic disease caused by mutations in the CFTR gene, is a life-limiting disease characterized by chronic bacterial airway infection and severe inflammation. Some CFTR mutants have reduced responsiveness to cAMP/PKA signaling; hence, pharmacological agents that elevate intracellular cAMP are potentially useful for the treatment of CF. By inhibiting cAMP breakdown, phosphodiesterase (PDE) inhibitors stimulate CFTR in vitro and in vivo. Here, we demonstrate that PDE inhibition by RPL554, a drug that has been shown to cause bronchodilation in asthma and chronic obstructive pulmonary disease (COPD) patients, stimulates CFTR-dependent ion secretion across bronchial epithelial cells isolated from patients carrying the R117H/F508del CF genotype. RPL554-induced CFTR activity was further increased by the potentiator VX-770, suggesting an additional benefit by the drug combination. RPL554 also increased cilia beat frequency in primary human bronchial epithelial cells. The results indicate RPL554 may increase mucociliary clearance through stimulation of CFTR and increasing ciliary beat frequency and thus could provide a novel therapeutic option for CF.
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Affiliation(s)
- Mark J Turner
- Department of Physiology, McIntyre Medical Sciences Building, McGill University, Montreal, Canada; McGill CF Translational Research Centre, Montreal, Canada;
| | - Elizabeth Matthes
- Department of Physiology, McIntyre Medical Sciences Building, McGill University, Montreal, Canada; McGill CF Translational Research Centre, Montreal, Canada
| | - Arnaud Billet
- Department of Physiology, McIntyre Medical Sciences Building, McGill University, Montreal, Canada; McGill CF Translational Research Centre, Montreal, Canada
| | - Amy J Ferguson
- Marsico Lung Institute, University of North Carolina, Chapel Hill, North Carolina
| | - David Y Thomas
- McGill CF Translational Research Centre, Montreal, Canada; Department of Biochemistry, McIntyre Medical Sciences Building, McGill University, Montreal, Canada
| | - Scott H Randell
- Department of Cell Biology and Physiology and the Marsico Lung Institute/Cystic Fibrosis Center, University of North Carolina, Chapel Hill, North Carolina
| | - Lawrence E Ostrowski
- Marsico Lung Institute, University of North Carolina, Chapel Hill, North Carolina
| | | | - John W Hanrahan
- Department of Physiology, McIntyre Medical Sciences Building, McGill University, Montreal, Canada; McGill CF Translational Research Centre, Montreal, Canada; Research Institute of the McGill University Health Centre, Montreal, Canada
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Billet A, Jia Y, Jensen T, Riordan JR, Hanrahan JW. Regulation of the cystic fibrosis transmembrane conductance regulator anion channel by tyrosine phosphorylation. FASEB J 2015; 29:3945-53. [PMID: 26062600 DOI: 10.1096/fj.15-273151] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2015] [Accepted: 05/26/2015] [Indexed: 11/11/2022]
Abstract
The cystic fibrosis transmembrane conductance regulator (CFTR) channel is activated by PKA phosphorylation of a regulatory domain that interacts dynamically with multiple CFTR domains and with other proteins. The large number of consensus sequences for phosphorylation by PKA has naturally focused most attention on regulation by this kinase. We report here that human CFTR is also phosphorylated by the tyrosine kinases p60c-Src (proto-oncogene tyrosine-protein kinase) and the proline-rich tyrosine kinase 2 (Pyk2), and they can also cause robust activation of quiescent CFTR channels. In excised patch-clamp experiments, CFTR activity during exposure to Src or Pyk2 reached ∼80% of that stimulated by PKA. Exposure to PKA after Src or Pyk2 caused a further increase to the level induced by PKA alone, implying a common limiting step. Channels became spontaneously active when v-Src or the catalytic domain of Pyk2 was coexpressed with CFTR and were further stimulated by the tyrosine phosphatase inhibitor dephostatin. Exogenous Src also activated 15SA-CFTR, a variant that lacks 15 potential PKA sites and has little response to PKA. PKA-independent activation by tyrosine phosphorylation has implications for the mechanism of regulation by the R domain and for the physiologic functions of CFTR.
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Affiliation(s)
- Arnaud Billet
- *Department of Physiology and Cystic Fibrosis Translational Research Centre, McGill University, Montreal, Quebec, Canada; Department of Biochemistry and Biophysics and Cystic Fibrosis Research Center, University of North Carolina, Chapel Hill, Chapel Hill, North Carolina, USA; and Research Institute of the McGill University Hospital Centre, Montreal, Quebec, Canada
| | - Yanlin Jia
- *Department of Physiology and Cystic Fibrosis Translational Research Centre, McGill University, Montreal, Quebec, Canada; Department of Biochemistry and Biophysics and Cystic Fibrosis Research Center, University of North Carolina, Chapel Hill, Chapel Hill, North Carolina, USA; and Research Institute of the McGill University Hospital Centre, Montreal, Quebec, Canada
| | - Tim Jensen
- *Department of Physiology and Cystic Fibrosis Translational Research Centre, McGill University, Montreal, Quebec, Canada; Department of Biochemistry and Biophysics and Cystic Fibrosis Research Center, University of North Carolina, Chapel Hill, Chapel Hill, North Carolina, USA; and Research Institute of the McGill University Hospital Centre, Montreal, Quebec, Canada
| | - John R Riordan
- *Department of Physiology and Cystic Fibrosis Translational Research Centre, McGill University, Montreal, Quebec, Canada; Department of Biochemistry and Biophysics and Cystic Fibrosis Research Center, University of North Carolina, Chapel Hill, Chapel Hill, North Carolina, USA; and Research Institute of the McGill University Hospital Centre, Montreal, Quebec, Canada
| | - John W Hanrahan
- *Department of Physiology and Cystic Fibrosis Translational Research Centre, McGill University, Montreal, Quebec, Canada; Department of Biochemistry and Biophysics and Cystic Fibrosis Research Center, University of North Carolina, Chapel Hill, Chapel Hill, North Carolina, USA; and Research Institute of the McGill University Hospital Centre, Montreal, Quebec, Canada
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AbuArish A, Wiseman PW, Hanrahan JW. The Role of ROS in Tethering CFTR within Ceramide Platforms at the Plasma Membrane. Biophys J 2015. [DOI: 10.1016/j.bpj.2014.11.707] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
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44
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Kolate A, Kore G, Lesimple P, Baradia D, Patil S, Hanrahan JW, Misra A. Polymer assisted entrapment of netilmicin in PLGA nanoparticles for sustained antibacterial activity. J Microencapsul 2014; 32:61-74. [PMID: 25238317 DOI: 10.3109/02652048.2014.944951] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
This study was aimed to develop poly(dl-lactide-co-glycolide) (PLGA) nanoparticle of highly water soluble antibiotic drug, netilmicin sulfate (NS) with improved entrapment efficiency (EE) and antibacterial activity. Dextran sulfate was introduced as helper polymer to form electrostatic complex with NS. Nanoparticles were prepared by double emulsification method and optimized using 2(5-1) fractional factorial design. EE was mainly influenced by dextran sulfate: NS charge ratio and PLGA concentration, whereas particle size (PS) was affected by all factors examined. The optimized NS-loaded-NPs had EE and PS of 93.23 ± 2.7% and 140.83 ± 2.4 nm respectively. NS-loaded-NPs effectively inhibited bacterial growth compared to free NS. Sustained release protected its inactivation and reduced the decline in its killing activity over time even in presence of bronchial cells. A MIC value of 18 μg/mL was observed for NPs on P. aeruginosa. Therefore, NPs with sustained bactericidal efficiency against P. aeruginosa may provide therapeutic benefit in chronic pulmonary infection, like cystic fibrosis.
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Affiliation(s)
- Atul Kolate
- Pharmacy Department, Faculty of Technology and Engineering, The Maharaja Sayajirao University of Baroda , Vadodara, Gujarat , India , and
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45
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Carlile GW, Robert R, Goepp J, Matthes E, Liao J, Kus B, Macknight SD, Rotin D, Hanrahan JW, Thomas DY. Ibuprofen rescues mutant cystic fibrosis transmembrane conductance regulator trafficking. J Cyst Fibros 2014; 14:16-25. [PMID: 24974227 DOI: 10.1016/j.jcf.2014.06.001] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2013] [Revised: 05/27/2014] [Accepted: 06/01/2014] [Indexed: 11/30/2022]
Abstract
BACKGROUND Small molecules as shown by VX809 can rescue the mislocalization of F508del-CFTR. The aim of this study was to identify correctors with a clinical history and their targets of action. METHODS CFTR correctors were screened using two F508del-CFTR expressing cell based HTS assays. Electrophysiological studies using CFBE41o(-) and HBE cells and in-vivo mouse assays confirmed CFTR rescue. The target of action was attained using pharmacological inhibitors and siRNA to specific genes. RESULTS Ibuprofen was identified as a CFTR corrector. Ibuprofen treatment of polarized CFBE41o(-) monolayers increased the short-circuit current (Isc) response to stimulation. In vivo CF mice treatment with ibuprofen restored the CFTR trafficking. SiRNA knock down of cyclooxygenase expression caused partial F508del-CFTR correction. CONCLUSION These studies show that ibuprofen is a CFTR corrector and that it causes correction by COX-1 inhibition. Hence ibuprofen may be suitable to be part of a future CF combination therapy.
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Affiliation(s)
- Graeme W Carlile
- Cystic Fibrosis Translational Research Center, Dept. of Biochemistry, McGill University, Montreal, Quebec H3G1Y6, Canada.
| | - Renaud Robert
- Cystic Fibrosis Translational Research Center, Dept. of Physiology, McGill University, Montreal, Quebec H3G1Y6, Canada
| | - Julie Goepp
- Cystic Fibrosis Translational Research Center, Dept. of Physiology, McGill University, Montreal, Quebec H3G1Y6, Canada
| | - Elizabeth Matthes
- Cystic Fibrosis Translational Research Center, Dept. of Physiology, McGill University, Montreal, Quebec H3G1Y6, Canada
| | - Jie Liao
- Cystic Fibrosis Translational Research Center, Dept. of Physiology, McGill University, Montreal, Quebec H3G1Y6, Canada
| | - Bart Kus
- Hospital for Sick Children, Dept. of Biochemistry, University of Toronto, Ontario M5G 1X8, Canada
| | - Sean D Macknight
- Cystic Fibrosis Translational Research Center, Dept. of Biochemistry, McGill University, Montreal, Quebec H3G1Y6, Canada
| | - Daniela Rotin
- Hospital for Sick Children, Dept. of Biochemistry, University of Toronto, Ontario M5G 1X8, Canada
| | - John W Hanrahan
- Cystic Fibrosis Translational Research Center, Dept. of Physiology, McGill University, Montreal, Quebec H3G1Y6, Canada
| | - David Y Thomas
- Cystic Fibrosis Translational Research Center, Dept. of Biochemistry, McGill University, Montreal, Quebec H3G1Y6, Canada
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Abstract
The pH of airway epithelial secretions influences bacterial killing and mucus properties and is reduced by acidic pollutants, gastric reflux, and respiratory diseases such as cystic fibrosis (CF). The effect of acute acid loads depends on buffer capacity, however the buffering of airway secretions has not been well characterized. In this work we develop a method for titrating micro-scale (30 μl) volumes and use it to study fluid secreted by the human airway epithelial cell line Calu-3, a widely used model for submucosal gland serous cells. Microtitration curves revealed that HCO−3 is the major buffer. Peak buffer capacity (β) increased from 17 to 28 mM/pH during forskolin stimulation, and was reduced by >50% in fluid secreted by cystic fibrosis transmembrane conductance regulator (CFTR)-deficient Calu-3 monolayers, confirming an important role of CFTR in HCO−3 secretion. Back-titration with NaOH revealed non-volatile buffer capacity due to proteins synthesized and released by the epithelial cells. Lysozyme and mucin concentrations were too low to buffer Calu-3 fluid significantly, however model titrations of porcine gastric mucins at concentrations near the sol-gel transition suggest that mucins may contribute to the buffer capacity of ASL in vivo. We conclude that CFTR-dependent HCO−3 secretion and epithelially-derived proteins are the predominant buffers in Calu-3 secretions.
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Affiliation(s)
- Dusik Kim
- Department of Physiology, McGill University Montréal, QC, Canada
| | - Jie Liao
- Department of Physiology, McGill University Montréal, QC, Canada
| | - John W Hanrahan
- Department of Physiology, McGill University Montréal, QC, Canada ; McGill University Health Centre Research Institute Montréal, QC, Canada
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AbuArish A, Pandzic E, Wiseman PW, Hanrahan JW. CFTR Clustering and Tethering in Ceramide-Platforms in Response to Post-Infection PKC Stimulation. Biophys J 2014. [DOI: 10.1016/j.bpj.2013.11.3467] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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48
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LeSimple P, Goepp J, Palmer ML, Fahrenkrug SC, O’Grady SM, Ferraro P, Robert R, Hanrahan JW. Cystic Fibrosis Transmembrane Conductance Regulator Is Expressed in Mucin Granules from Calu-3 and Primary Human Airway Epithelial Cells. Am J Respir Cell Mol Biol 2013; 49:511-6. [DOI: 10.1165/rcmb.2012-0419rc] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
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Hanrahan JW, Sampson HM, Thomas DY. Novel pharmacological strategies to treat cystic fibrosis. Trends Pharmacol Sci 2013; 34:119-25. [PMID: 23380248 DOI: 10.1016/j.tips.2012.11.006] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2012] [Revised: 11/28/2012] [Accepted: 11/28/2012] [Indexed: 12/15/2022]
Abstract
Cystic fibrosis (CF) is a lethal disease caused by mutations in the CFTR gene. The most frequent mutation is deletion of a phenylalanine residue (ΔF508) that results in retention of the mutant, but otherwise functional, protein in the endoplasmic reticulum (ER). There have been recent advances in the identification of chemically diverse corrector compounds that allow ΔF508-CFTR protein to traffic from the ER to the plasma membrane. The most studied correctors fall into two categories, pharmacological chaperones that bind to the mutant protein and circumvent its recognition by the cellular protein quality control systems and proteostasis regulators that modify the cellular pathways responsible for protein quality control and trafficking. This review focuses on recent advances in the field, strategies for the development of drugs from corrector compounds for the treatment of CF, and identification of their targets and mechanism(s) of action.
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Affiliation(s)
- John W Hanrahan
- Cystic Fibrosis Translation Research centre, Faculty of Medicine, McGill University, 3655 Promenade Sir William Osler, Montreal H3G 1Y6, Quebec, Canada
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Abstract
cAMP-stimulated anion conductance is defective in cystic fibrosis (CF). The regulatory domain of CFTR, the anion channel protein encoded by the CF gene, possesses an unusually high density of consensus sequences for phosphorylation by protein kinase A (14 in a stretch of <200 amino acids). Thus it is not surprising that CFTR is viewed primarily as a cAMP-stimulated anion channel, and most studies have focused on this mode of activation. However, there is growing evidence that CFTR also responds to Ca(2+)-mobilizing secretagogues and contributes substantially to cholinergic and purinergic responses in native tissues. G protein-coupled receptors that signal through Gαq can stimulate CFTR channels by activating Ca(2+)-dependent adenylyl cyclase and tyrosine kinases, and also by inhibiting protein phosphatase type 2A. Here we review evidence for these novel mechanisms of CFTR activation and discuss how they may help explain previous observations.
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Affiliation(s)
- Arnaud Billet
- J. W. Hanrahan: Department of Physiology, McGill University, 3655 Promenade Sir William Osler, Montreal, QC, Canada H3G 1Y6.
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