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Castaldo A, Gelzo M, Iacotucci P, Longobardi A, Taccetti G, Terlizzi V, Carnovale V. One year of treatment with elexacaftor/tezacaftor/ivacaftor in patients with cystic fibrosis homozygous for the F508del mutation causes a significant increase in liver biochemical indexes. Front Mol Biosci 2024; 10:1327958. [PMID: 38259684 PMCID: PMC10800484 DOI: 10.3389/fmolb.2023.1327958] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Accepted: 12/01/2023] [Indexed: 01/24/2024] Open
Abstract
Introduction: Modulators of cystic fibrosis transmembrane conductance regulator mutated protein significantly improved the outcome of patients with cystic fibrosis (CF). We describe 63 patients who were independently followed up in two CF regional centers (i.e., Campania and Tuscany regions). Methods: All patients were homozygous for the F508del mutation and were treated with lumacaftor/ivacaftor (LI) for 3 years, followed by 1 year of treatment with elexacaftor/tezacaftor/ivacaftor (ETI). We studied the biochemical parameters of liver damage and cholesterol metabolism. Results: Beyond the improvement of BMI and lung function with LI treatment and even more with ETI, we found that the 3 years of LI treatment significantly improved liver function parameters (total and conjugated bilirubin, ALT, AP, and GGT), while the subsequent ETI treatment caused a significant increase of such parameters. Discussion: We confirm that treatment with LI does not correct hypocholesterolemia, whereas treatment with ETI significantly increases serum cholesterol. Such an increase is likely due to enhanced de novo biosynthesis, as indicated by the significant increase in serum lathosterol, and it is likely that the subsequent liver cholesterol accumulation may contribute to triggering inflammation and worsening liver biochemical indexes. The increase in serum bilirubin and ALT that we observed in approximately 94% and 84% of patients treated with ETI, respectively, suggests further investigation of the impact of ETI therapy on liver function indexes.
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Affiliation(s)
- Alice Castaldo
- Dipartimento di Scienze Mediche Traslazionali, Centro Regionale Fibrosi Cistica del Bambino - Pediatria, Università di Napoli Federico II, Naples, Italy
- Ospedale Pediatrico Meyer IRCCS, Dipartimento di Scienze della Salute, Florence, Italy
- CEINGE-Biotecnologie Avanzate Franco Salvatore, Naples, Italy
| | - Monica Gelzo
- CEINGE-Biotecnologie Avanzate Franco Salvatore, Naples, Italy
- Dipartimento di Medicina Molecolare e Biotecnologie Mediche, Università di Napoli Federico II, Naples, Italy
| | - Paola Iacotucci
- Dipartimento di Medicina Clinica e Chirurgia, Università di Napoli Federico II, Naples, Italy
| | | | - Giovanni Taccetti
- Meyer Children’s Hospital IRCCS, Centro Regionale Toscano per la cura della Fibrosi Cistica, Dipartimento di Pediatria, Firenze, Italy
| | - Vito Terlizzi
- Meyer Children’s Hospital IRCCS, Centro Regionale Toscano per la cura della Fibrosi Cistica, Dipartimento di Pediatria, Firenze, Italy
| | - Vincenzo Carnovale
- Dipartimento di Scienze Mediche Traslazionali, Centro Regionale Fibrosi Cistica dell’Adulto – Geriatria, Università di Napoli Federico II, Naples, Italy
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Schnitker F, Liu Y, Keitsch S, Soddemann M, Verhasselt HL, Kehrmann J, Grassmé H, Kamler M, Gulbins E, Wu Y. Reduced Sphingosine in Cystic Fibrosis Increases Susceptibility to Mycobacterium abscessus Infections. Int J Mol Sci 2023; 24:14004. [PMID: 37762308 PMCID: PMC10530875 DOI: 10.3390/ijms241814004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Revised: 09/06/2023] [Accepted: 09/08/2023] [Indexed: 09/29/2023] Open
Abstract
Cystic fibrosis (CF) is an autosomal recessive disorder caused by the deficiency of the cystic fibrosis transmembrane conductance regulator (CFTR) and often leads to pulmonary infections caused by various pathogens, including Staphylococcus aureus, Pseudomonas aeruginosa, and nontuberculous mycobacteria, particularly Mycobacterium abscessus. Unfortunately, M. abscessus infections are increasing in prevalence and are associated with the rapid deterioration of CF patients. The treatment options for M. abscessus infections are limited, requiring the urgent need to comprehend infectious pathogenesis and develop new therapeutic interventions targeting affected CF patients. Here, we show that the deficiency of CFTR reduces sphingosine levels in bronchial and alveolar epithelial cells and macrophages from CF mice and humans. Decreased sphingosine contributes to the susceptibility of CF tissues to M. abscessus infection, resulting in a higher incidence of infections in CF mice. Notably, treatment of M. abscessus with sphingosine demonstrated potent bactericidal activity against the pathogen. Most importantly, restoration of sphingosine levels in CF cells, whether human or mouse, and in the lungs of CF mice, provided protection against M. abscessus infections. Our findings demonstrate that pulmonary sphingosine levels are important in controlling M. abscessus infection. These results offer a promising therapeutic avenue for CF patients with pulmonary M. abscessus infections.
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Affiliation(s)
- Fabian Schnitker
- Department of Molecular Biology, Institute of Molecular Biology, University Hospital Essen, University of Duisburg-Essen, 45122 Essen, Germany; (F.S.); (Y.L.); (S.K.); (M.S.); (H.G.); (E.G.)
| | - Yongjie Liu
- Department of Molecular Biology, Institute of Molecular Biology, University Hospital Essen, University of Duisburg-Essen, 45122 Essen, Germany; (F.S.); (Y.L.); (S.K.); (M.S.); (H.G.); (E.G.)
- West German Heart and Vascular Center, Thoracic Transplantation, Department of Thoracic and Cardiovascular Surgery, University Hospital Essen, University Duisburg-Essen, 45122 Essen, Germany;
| | - Simone Keitsch
- Department of Molecular Biology, Institute of Molecular Biology, University Hospital Essen, University of Duisburg-Essen, 45122 Essen, Germany; (F.S.); (Y.L.); (S.K.); (M.S.); (H.G.); (E.G.)
| | - Matthias Soddemann
- Department of Molecular Biology, Institute of Molecular Biology, University Hospital Essen, University of Duisburg-Essen, 45122 Essen, Germany; (F.S.); (Y.L.); (S.K.); (M.S.); (H.G.); (E.G.)
| | - Hedda Luise Verhasselt
- Institute of Medical Microbiology, University Hospital Essen, University of Duisburg-Essen, 45122 Essen, Germany; (H.L.V.); (J.K.)
| | - Jan Kehrmann
- Institute of Medical Microbiology, University Hospital Essen, University of Duisburg-Essen, 45122 Essen, Germany; (H.L.V.); (J.K.)
| | - Heike Grassmé
- Department of Molecular Biology, Institute of Molecular Biology, University Hospital Essen, University of Duisburg-Essen, 45122 Essen, Germany; (F.S.); (Y.L.); (S.K.); (M.S.); (H.G.); (E.G.)
| | - Markus Kamler
- West German Heart and Vascular Center, Thoracic Transplantation, Department of Thoracic and Cardiovascular Surgery, University Hospital Essen, University Duisburg-Essen, 45122 Essen, Germany;
| | - Erich Gulbins
- Department of Molecular Biology, Institute of Molecular Biology, University Hospital Essen, University of Duisburg-Essen, 45122 Essen, Germany; (F.S.); (Y.L.); (S.K.); (M.S.); (H.G.); (E.G.)
- Department of Surgery, University of Cincinnati College of Medicine, Cincinnati, OH 45229, USA
| | - Yuqing Wu
- Department of Molecular Biology, Institute of Molecular Biology, University Hospital Essen, University of Duisburg-Essen, 45122 Essen, Germany; (F.S.); (Y.L.); (S.K.); (M.S.); (H.G.); (E.G.)
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3
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Shrestha N, McCarron A, Rout-Pitt N, Donnelley M, Parsons DW, Hryciw DH. Essential Fatty Acid Deficiency in Cystic Fibrosis Disease Progression: Role of Genotype and Sex. Nutrients 2022; 14:nu14214666. [PMID: 36364928 PMCID: PMC9657825 DOI: 10.3390/nu14214666] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Revised: 11/01/2022] [Accepted: 11/01/2022] [Indexed: 11/06/2022] Open
Abstract
Adequate intake of nutrients such as essential fatty acids (EFA) are critical in cystic fibrosis (CF). The clinical course of deterioration of lung function in people with CF has been shown to relate to nutrition. Independent of the higher energy consumption and malabsorption due to pancreatic insufficiency, EFA deficiency is closely associated with the risk of pulmonary infection, the most significant pathology in CF. This review will focus on the EFA deficiency identified in people with CF, as well as the limited progress made in deciphering the exact metabolic pathways that are dysfunctional in CF. Specifically, people with CF are deficient in linoleic acid, an omega 6 fatty acid, and the ratio of arachidonic acid (omega 6 metabolite) and docosahexaenoic acid (omega 3 metabolite) is increased. Analysis of the molecular pathways in bronchial cells has identified changes in the enzymes that metabolise EFA. However, fatty acid metabolism primarily occurs in the liver, with EFA metabolism in CF liver not yet investigated, indicating that further research is required. Despite limited understanding in this area, it is well known that adequate EFA concentrations are critical to normal membrane structure and function, and thus are important to consider in disease processes. Novel insights into the relationship between CF genotype and EFA phenotype will be discussed, in addition to sex differences in EFA concentrations in people with CF. Collectively, investigating the specific effects of genotype and sex on fatty acid metabolism may provide support for the management of people with CF via personalised genotype- and sex-specific nutritional therapies.
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Affiliation(s)
- Nirajan Shrestha
- School of Pharmacy and Medical Sciences, Griffith University, Southport, QLD 4222, Australia
| | - Alexandra McCarron
- Adelaide Medical School, University of Adelaide, Adelaide, SA 5001, Australia
- Robinson Research Institute, University of Adelaide, Adelaide, SA 5001, Australia
- Respiratory and Sleep Medicine, Women’s and Children’s Hospital, 72 King William Road, North Adelaide, SA 5006, Australia
| | - Nathan Rout-Pitt
- Adelaide Medical School, University of Adelaide, Adelaide, SA 5001, Australia
- Robinson Research Institute, University of Adelaide, Adelaide, SA 5001, Australia
- Respiratory and Sleep Medicine, Women’s and Children’s Hospital, 72 King William Road, North Adelaide, SA 5006, Australia
| | - Martin Donnelley
- Adelaide Medical School, University of Adelaide, Adelaide, SA 5001, Australia
- Robinson Research Institute, University of Adelaide, Adelaide, SA 5001, Australia
- Respiratory and Sleep Medicine, Women’s and Children’s Hospital, 72 King William Road, North Adelaide, SA 5006, Australia
| | - David W. Parsons
- Adelaide Medical School, University of Adelaide, Adelaide, SA 5001, Australia
- Robinson Research Institute, University of Adelaide, Adelaide, SA 5001, Australia
- Respiratory and Sleep Medicine, Women’s and Children’s Hospital, 72 King William Road, North Adelaide, SA 5006, Australia
| | - Deanne H. Hryciw
- School of Environment and Science, Griffith University, Nathan, QLD 4111, Australia
- Institute for Health and Sport, Victoria University, Melbourne, VIC 3000, Australia
- Griffith Institute for Drug Discovery, Griffith University, Nathan, QLD 4111, Australia
- Correspondence: ; Tel.: +61-7-3735-3601
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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] [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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Hryciw DH, Jackson CA, Shrestha N, Parsons D, Donnelley M, McAinch AJ. Role for animal models in understanding essential fatty acid deficiency in cystic fibrosis. Cell Mol Life Sci 2021; 78:7991-7999. [PMID: 34741185 PMCID: PMC11072998 DOI: 10.1007/s00018-021-04014-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Revised: 10/11/2021] [Accepted: 10/25/2021] [Indexed: 10/19/2022]
Abstract
Essential fatty acid deficiency has been observed in most patients with Cystic Fibrosis (CF); however, pancreatic supplementation does not restore the deficiency, suggesting a different pathology independent of the pancreas. At this time, the underlying pathological mechanisms are largely unknown. Essential fatty acids are obtained from the diet and processed by organs including the liver and intestine, two organs significantly impacted by mutations in the cystic fibrosis transmembrane conductance regulator gene (Cftr). There are several CF animal models in a variety of species that have been developed to investigate molecular mechanisms associated with the CF phenotype. Specifically, global and systemic mutations in Cftr which mimic genotypic changes identified in CF patients have been generated in mice, rats, sheep, pigs and ferrets. These mutations produce CFTR proteins with a gating defect, trafficking defect, or an absent or inactive CFTR channel. Essential fatty acids are critical to CFTR function, with a bidirectional relationship between CFTR and essential fatty acids proposed. Currently, there are limited analyses on the essential fatty acid status in most of these animal models. Of interest, in the mouse model, essential fatty acid status is dependent on the genotype and resultant phenotype of the mouse. Future investigations should identify an optimal animal model that has most of the phenotypic changes associated with CF including the essential fatty acid deficiencies, which can be used in the development of therapeutics.
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Affiliation(s)
- Deanne H Hryciw
- School of Environment and Science, Griffith University, Nathan, QLD, Australia.
- Centre for Planetary Health and Food Security, Griffith University, Nathan, QLD, Australia.
- Institute for Health and Sport, Victoria University, Melbourne, VIC, Australia.
| | - Courtney A Jackson
- School of Environment and Science, Griffith University, Nathan, QLD, Australia
| | - Nirajan Shrestha
- School of Pharmacy and Medical Sciences, Griffith University, Southport, QLD, Australia
| | - David Parsons
- Adelaide Medical School, University of Adelaide, Adelaide, SA, Australia
- Respiratory and Sleep Medicine, Women's and Children's Hospital, North Adelaide, SA, Australia
- Robinson Research Institute, University of Adelaide, Adelaide, SA, Australia
| | - Martin Donnelley
- Adelaide Medical School, University of Adelaide, Adelaide, SA, Australia
- Respiratory and Sleep Medicine, Women's and Children's Hospital, North Adelaide, SA, Australia
- Robinson Research Institute, University of Adelaide, Adelaide, SA, Australia
| | - Andrew J McAinch
- Institute for Health and Sport, Victoria University, Melbourne, VIC, Australia
- Australian Institute for Musculoskeletal Science (AIMSS), Victoria University, St. Albans, VIC, Australia
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6
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Amato F, Castaldo A, Castaldo G, Cernera G, Corso G, Ferrari E, Gelzo M, Monzani R, Villella VR, Raia V. Impaired cholesterol metabolism in the mouse model of cystic fibrosis. A preliminary study. PLoS One 2021; 16:e0245302. [PMID: 33412572 PMCID: PMC7790534 DOI: 10.1371/journal.pone.0245302] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Accepted: 12/24/2020] [Indexed: 11/19/2022] Open
Abstract
This study aims to investigate cholesterol metabolism in a mouse model with cystic fibrosis (CF) by the comparison of affected homozygous versus wild type (WT) mice. In particular, we evaluated the effects of a diet enriched with cholesterol in both mice groups in comparison with the normal diet. To this purpose, beyond serum and liver cholesterol, we analyzed serum phytosterols as indirect markers of intestinal absorption of cholesterol, liver lathosterol as indirect marker of de novo cholesterol synthesis, liver cholestanol (a catabolite of bile salts synthesis) and the liver mRNA levels of LDL receptor (LDLR), 3-hydroxy-3-methylglutaryl-CoA reductase (HMG-CoAR), acyl CoA:cholesterol acyl transferase 2 (ACAT2), cytochrome P450 7A1 (CYP7A1) and tumor necrosis factor alpha (TNFα). CF mice showed lower intestinal absorption and higher liver synthesis of cholesterol than WT mice. In WT mice, the cholesterol supplementation inhibits the synthesis of liver cholesterol and enhances its catabolism, while in CF mice we did not observe a reduction of LDLR and HMG-CoAR expression (probably due to an altered feed-back), causing an increase of intracellular cholesterol. In addition, we observed a further increase (5-fold) in TNFα mRNA levels. This preliminary study suggests that in CF mice there is a vicious circle in which the altered synthesis/secretion of bile salts may reduce the digestion/absorption of cholesterol. As a result, the liver increases the biosynthesis of cholesterol that accumulates in the cells, triggering inflammation and further compromising the metabolism of bile salts.
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Affiliation(s)
- Felice Amato
- Dipartimento di Medicina Molecolare e Biotecnologie Mediche, University of Naples Federico II, Naples, Italy
- CEINGE-Biotecnologie Avanzate, Scarl, Naples, Italy
| | - Alice Castaldo
- Dipartimento di Scienze Mediche Traslazionali, University of Naples Federico II, Naples, Italy
| | - Giuseppe Castaldo
- Dipartimento di Medicina Molecolare e Biotecnologie Mediche, University of Naples Federico II, Naples, Italy
- CEINGE-Biotecnologie Avanzate, Scarl, Naples, Italy
| | - Gustavo Cernera
- Dipartimento di Medicina Molecolare e Biotecnologie Mediche, University of Naples Federico II, Naples, Italy
- CEINGE-Biotecnologie Avanzate, Scarl, Naples, Italy
| | - Gaetano Corso
- Dipartimento di Medicina Clinica e Sperimentale, University of Foggia, Foggia, Italy
- * E-mail:
| | - Eleonora Ferrari
- European Institute for Research in Cystic Fibrosis, San Raffaele Scientific Institute, Milan, Italy
- Dipartimento di Scienze della Salute, University of Eastern Piedmont, Novara, Italy
| | - Monica Gelzo
- Dipartimento di Medicina Molecolare e Biotecnologie Mediche, University of Naples Federico II, Naples, Italy
- CEINGE-Biotecnologie Avanzate, Scarl, Naples, Italy
| | - Romina Monzani
- European Institute for Research in Cystic Fibrosis, San Raffaele Scientific Institute, Milan, Italy
- Dipartimento di Scienze della Salute, University of Eastern Piedmont, Novara, Italy
| | - Valeria Rachela Villella
- European Institute for Research in Cystic Fibrosis, San Raffaele Scientific Institute, Milan, Italy
| | - Valeria Raia
- Dipartimento di Scienze Mediche Traslazionali, University of Naples Federico II, Naples, Italy
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Mingione A, Ottaviano E, Barcella M, Merelli I, Rosso L, Armeni T, Cirilli N, Ghidoni R, Borghi E, Signorelli P. Cystic Fibrosis Defective Response to Infection Involves Autophagy and Lipid Metabolism. Cells 2020; 9:cells9081845. [PMID: 32781626 PMCID: PMC7463682 DOI: 10.3390/cells9081845] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 07/31/2020] [Accepted: 08/04/2020] [Indexed: 12/14/2022] Open
Abstract
Cystic fibrosis (CF) is a hereditary disease, with 70% of patients developing a proteinopathy related to the deletion of phenylalanine 508. CF is associated with multiple organ dysfunction, chronic inflammation, and recurrent lung infections. CF is characterized by defective autophagy, lipid metabolism, and immune response. Intracellular lipid accumulation favors microbial infection, and autophagy deficiency impairs internalized pathogen clearance. Myriocin, an inhibitor of sphingolipid synthesis, significantly reduces inflammation, promotes microbial clearance in the lungs, and induces autophagy and lipid oxidation. RNA-seq was performed in Aspergillusfumigatus-infected and myriocin-treated CF patients’ derived monocytes and in a CF bronchial epithelial cell line. Fungal clearance was also evaluated in CF monocytes. Myriocin enhanced CF patients’ monocytes killing of A. fumigatus. CF patients’ monocytes and cell line responded to infection with a profound transcriptional change; myriocin regulates genes that are involved in inflammation, autophagy, lipid storage, and metabolism, including histones and heat shock proteins whose activity is related to the response to infection. We conclude that the regulation of sphingolipid synthesis induces a metabolism drift by promoting autophagy and lipid consumption. This process is driven by a transcriptional program that corrects part of the differences between CF and control samples, therefore ameliorating the infection response and pathogen clearance in the CF cell line and in CF peripheral blood monocytes.
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Affiliation(s)
- Alessandra Mingione
- Biochemistry and Molecular Biology Laboratory, Health Science Department, University of Milan, San Paolo Hospital, 20142 Milan, Italy; (A.M.); (R.G.)
| | - Emerenziana Ottaviano
- Laboratory of Clinical Microbiology, Health Science Department, University of Milan, San Paolo Hospital, 20142 Milan, Italy; (E.O.); (M.B.); (E.B.)
| | - Matteo Barcella
- Laboratory of Clinical Microbiology, Health Science Department, University of Milan, San Paolo Hospital, 20142 Milan, Italy; (E.O.); (M.B.); (E.B.)
| | - Ivan Merelli
- National Research Council of Italy, Institute for Biomedical Technologies, Via Fratelli Cervi 93, 20090 Milan, Italy;
| | - Lorenzo Rosso
- Health Sciences Department, University of Milan, Thoracic surgery and transplantation Unit, Fondazione IRCCS Ca Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy;
| | - Tatiana Armeni
- Department of Clinical Sciences, Section of Biochemistry, Biology and Physics, Polytechnic University of Marche, 60131 Ancona, Italy;
| | - Natalia Cirilli
- Cystic Fibrosis Referral Care Center, Mother-Child Department, United Hospitals Le Torrette, 60126 Ancona, Italy;
| | - Riccardo Ghidoni
- Biochemistry and Molecular Biology Laboratory, Health Science Department, University of Milan, San Paolo Hospital, 20142 Milan, Italy; (A.M.); (R.G.)
- “Aldo Ravelli” Center for Neurotechnology and Experimental Brain Therapeutics, via Antonio di Rudinì 8, 20142 Milan, Italy
| | - Elisa Borghi
- Laboratory of Clinical Microbiology, Health Science Department, University of Milan, San Paolo Hospital, 20142 Milan, Italy; (E.O.); (M.B.); (E.B.)
| | - Paola Signorelli
- Biochemistry and Molecular Biology Laboratory, Health Science Department, University of Milan, San Paolo Hospital, 20142 Milan, Italy; (A.M.); (R.G.)
- Correspondence:
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Dei Cas M, Zulueta A, Mingione A, Caretti A, Ghidoni R, Signorelli P, Paroni R. An Innovative Lipidomic Workflow to Investigate the Lipid Profile in a Cystic Fibrosis Cell Line. Cells 2020; 9:E1197. [PMID: 32408521 PMCID: PMC7291020 DOI: 10.3390/cells9051197] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 05/07/2020] [Accepted: 05/08/2020] [Indexed: 12/22/2022] Open
Abstract
Altered lipid metabolism has been associated to cystic fibrosis disease, which is characterized by chronic lung inflammation and various organs dysfunction. Here, we present the validation of an untargeted lipidomics approach based on high-resolution mass spectrometry aimed at identifying those lipid species that unequivocally sign CF pathophysiology. Of n.13375 mass spectra recorded on cystic fibrosis bronchial epithelial airways epithelial cells IB3, n.7787 presented the MS/MS data, and, after software and manual validation, the final number of annotated lipids was restricted to n.1159. On these lipids, univariate and multivariate statistical approaches were employed in order to select relevant lipids for cellular phenotype discrimination between cystic fibrosis and HBE healthy cells. In cystic fibrosis IB3 cells, a pervasive alteration in the lipid metabolism revealed changes in the classes of ether-linked phospholipids, cholesterol esters, and glycosylated sphingolipids. Through functions association, it was evidenced that lipids variation involves the moiety implicated in membrane composition, endoplasmic reticulum, mitochondria compartments, and chemical and biophysical lipids properties. This study provides a new perspective in understanding the pathogenesis of cystic fibrosis and strengthens the need to use a validated mass spectrometry-based lipidomics approach for the discovery of potential biomarkers and perturbed metabolism.
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Affiliation(s)
- Michele Dei Cas
- Laboratory of Clinical Biochemistry and Mass Spectrometry, Department of Health Sciences, Università degli Studi di Milano, 20142 Milan, Italy;
- Laboratory of Biochemistry and Molecular Biology, Department of Health Sciences, Università degli Studi di Milano, 20142 Milan, Italy; (A.Z.); (A.M.); (A.C.); (R.G.); (P.S.)
| | - Aida Zulueta
- Laboratory of Biochemistry and Molecular Biology, Department of Health Sciences, Università degli Studi di Milano, 20142 Milan, Italy; (A.Z.); (A.M.); (A.C.); (R.G.); (P.S.)
| | - Alessandra Mingione
- Laboratory of Biochemistry and Molecular Biology, Department of Health Sciences, Università degli Studi di Milano, 20142 Milan, Italy; (A.Z.); (A.M.); (A.C.); (R.G.); (P.S.)
- Aldo Ravelli Center for Neurotechnology and Experimental Brain Therapeutics, Department of Health Sciences, Università degli Studi di Milano, 20142 Milan, Italy
| | - Anna Caretti
- Laboratory of Biochemistry and Molecular Biology, Department of Health Sciences, Università degli Studi di Milano, 20142 Milan, Italy; (A.Z.); (A.M.); (A.C.); (R.G.); (P.S.)
| | - Riccardo Ghidoni
- Laboratory of Biochemistry and Molecular Biology, Department of Health Sciences, Università degli Studi di Milano, 20142 Milan, Italy; (A.Z.); (A.M.); (A.C.); (R.G.); (P.S.)
- Aldo Ravelli Center for Neurotechnology and Experimental Brain Therapeutics, Department of Health Sciences, Università degli Studi di Milano, 20142 Milan, Italy
| | - Paola Signorelli
- Laboratory of Biochemistry and Molecular Biology, Department of Health Sciences, Università degli Studi di Milano, 20142 Milan, Italy; (A.Z.); (A.M.); (A.C.); (R.G.); (P.S.)
| | - Rita Paroni
- Laboratory of Clinical Biochemistry and Mass Spectrometry, Department of Health Sciences, Università degli Studi di Milano, 20142 Milan, Italy;
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Abstract
Cystic Fibrosis (CF) is the most common life-shortening genetic disease among Caucasians, resulting from mutations in the gene encoding the Cystic Fibrosis Transmembrane conductance Regulator (CFTR). While work to understand this protein has resulted in new treatment strategies, it is important to emphasize that CFTR exists within a complex lipid bilayer — a concept largely overlooked when performing structural and functional studies. In this review we discuss cellular lipid imbalances in CF, mechanisms by which lipids affect membrane protein activity, and the specific impact of detergents and lipids on CFTR function. In this review, Cottrill et al. discuss how the Cystic Fibrosis Transmembrane conductance Regulator (CFTR) interacts with the membrane into which it is inserted. They summarize recent insight into the ways lipids are imbalanced in CF epithelia and how the lipid environment affects CFTR.
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Lu B, Corey DA, Kelley TJ. Resveratrol restores intracellular transport in cystic fibrosis epithelial cells. Am J Physiol Lung Cell Mol Physiol 2020; 318:L1145-L1157. [PMID: 32267731 DOI: 10.1152/ajplung.00006.2020] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
We have demonstrated previously that intracellular transport is impaired in cystic fibrosis (CF) epithelial cells. This impairment is related to both growth and inflammatory regulation in CF cell and animal models. Understanding how transport in CF cells is regulated and identifying means to manipulate that regulation are key to identifying new therapies that can address key CF phenotypes. It was hypothesized that resveratrol could replicate these benefits since it interfaces with multiple pathways identified to affect microtubule regulation in CF. It was found that resveratrol treatment significantly restored intracellular transport as determined by monitoring both cholesterol distribution and the distribution of rab7-positive organelles in CF cells. This restoration of intracellular transport is due to correction of both microtubule formation rates and microtubule acetylation in cultured CF cell models and primary nasal epithelial cells. Mechanistically, the effect of resveratrol on microtubule regulation and intracellular transport was dependent on peroxisome proliferator-activated receptor-γ signaling and its ability to act as a pan-histone deacetylase (HDAC) inhibitor. Resveratrol represents a candidate compound with known anti-inflammatory properties that can restore both microtubule formation and acetylation in CF epithelial cells.
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Affiliation(s)
- Binyu Lu
- Department of Pediatrics, Case Western Reserve University, Cleveland, Ohio
| | - Deborah A Corey
- Department of Pediatrics, Case Western Reserve University, Cleveland, Ohio
| | - Thomas J Kelley
- Department of Pediatrics, Case Western Reserve University, Cleveland, Ohio
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11
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Favia M, de Bari L, Bobba A, Atlante A. An Intriguing Involvement of Mitochondria in Cystic Fibrosis. J Clin Med 2019; 8:jcm8111890. [PMID: 31698802 PMCID: PMC6912654 DOI: 10.3390/jcm8111890] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Revised: 10/31/2019] [Accepted: 11/04/2019] [Indexed: 12/16/2022] Open
Abstract
Cystic fibrosis (CF) occurs when the cystic fibrosis transmembrane conductance regulator (CFTR) protein is not synthetized and folded correctly. The CFTR protein helps to maintain the balance of salt and water on many body surfaces, such as the lung surface. When the protein is not working correctly, chloride becomes trapped in cells, then water cannot hydrate the cellular surface and the mucus covering the cells becomes thick and sticky. Furthermore, a defective CFTR appears to produce a redox imbalance in epithelial cells and extracellular fluids and to cause an abnormal generation of reactive oxygen species: as a consequence, oxidative stress has been implicated as a causative factor in the aetiology of the process. Moreover, massive evidences show that defective CFTR gives rise to extracellular GSH level decrease and elevated glucose concentrations in airway surface liquid (ASL), thus encouraging lung infection by pathogens in the CF advancement. Recent research in progress aims to rediscover a possible role of mitochondria in CF. Here the latest new and recent studies on mitochondrial bioenergetics are collected. Surprisingly, they have enabled us to ascertain that mitochondria have a leading role in opposing the high ASL glucose level as well as oxidative stress in CF.
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Affiliation(s)
- Maria Favia
- Istituto di Biomembrane, Bioenergetica e Biotecnologie Molecolari—CNR, Via G. Amendola 122/O, 70126 Bari, Italy; (L.d.B.); (A.B.)
- Dipartimento di Bioscienze, Biotecnologie e Biofarmaceutica, Università di Bari, Via E. Orabona 4, 70126 Bari, Italy
- Correspondence: (M.F.); (A.A.)
| | - Lidia de Bari
- Istituto di Biomembrane, Bioenergetica e Biotecnologie Molecolari—CNR, Via G. Amendola 122/O, 70126 Bari, Italy; (L.d.B.); (A.B.)
| | - Antonella Bobba
- Istituto di Biomembrane, Bioenergetica e Biotecnologie Molecolari—CNR, Via G. Amendola 122/O, 70126 Bari, Italy; (L.d.B.); (A.B.)
| | - Anna Atlante
- Istituto di Biomembrane, Bioenergetica e Biotecnologie Molecolari—CNR, Via G. Amendola 122/O, 70126 Bari, Italy; (L.d.B.); (A.B.)
- Correspondence: (M.F.); (A.A.)
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12
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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] [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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13
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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] [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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14
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Akhtar N, Pradhan N, Saha A, Kumar V, Biswas O, Dey S, Shah M, Kumar S, Manna D. Tuning the solubility of ionophores: glutathione-mediated transport of chloride ions across hydrophobic membranes. Chem Commun (Camb) 2019; 55:8482-8485. [DOI: 10.1039/c9cc04518j] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Glutathione-mediated transformation of a water-soluble proanionophore to an active anionophore allows controlled transport of Cl− ion across hydrophobic lipid bilayers.
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Affiliation(s)
- Nasim Akhtar
- Department of Chemistry
- Indian Institute of Technology Guwahati
- Assam-781039
- India
| | - Nirmalya Pradhan
- Department of Chemistry
- Indian Institute of Technology Guwahati
- Assam-781039
- India
| | - Abhishek Saha
- Department of Chemistry
- Indian Institute of Technology Guwahati
- Assam-781039
- India
| | - Vishnu Kumar
- Department of Bioscience and Bioengineering
- Indian Institute of Technology Guwahati
- Assam-781039
- India
| | - Oindrila Biswas
- Department of Chemistry
- Indian Institute of Technology Guwahati
- Assam-781039
- India
| | - Subhasis Dey
- Department of Chemistry
- Indian Institute of Technology Guwahati
- Assam-781039
- India
| | - Manisha Shah
- Department of Bioscience and Bioengineering
- Indian Institute of Technology Guwahati
- Assam-781039
- India
| | - Sachin Kumar
- Department of Bioscience and Bioengineering
- Indian Institute of Technology Guwahati
- Assam-781039
- India
| | - Debasis Manna
- Department of Chemistry
- Indian Institute of Technology Guwahati
- Assam-781039
- India
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15
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White MM, Geraghty P, Hayes E, Cox S, Leitch W, Alfawaz B, Lavelle GM, McElvaney OJ, Flannery R, Keenan J, Meleady P, Henry M, Clynes M, Gunaratnam C, McElvaney NG, Reeves EP. Neutrophil Membrane Cholesterol Content is a Key Factor in Cystic Fibrosis Lung Disease. EBioMedicine 2017; 23:173-184. [PMID: 28835336 PMCID: PMC5605378 DOI: 10.1016/j.ebiom.2017.08.013] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Revised: 08/09/2017] [Accepted: 08/14/2017] [Indexed: 01/13/2023] Open
Abstract
Background Identification of mechanisms promoting neutrophil trafficking to the lungs of patients with cystic fibrosis (CF) is a challenge for next generation therapeutics. Cholesterol, a structural component of neutrophil plasma membranes influences cell adhesion, a key step in transmigration. The effect of chronic inflammation on neutrophil membrane cholesterol content in patients with CF (PWCF) remains unclear. To address this we examined neutrophils of PWCF to evaluate the cause and consequence of altered membrane cholesterol and identified the effects of lung transplantation and ion channel potentiator therapy on the cellular mechanisms responsible for perturbed membrane cholesterol and increased cell adhesion. Methodology PWCF homozygous for the ΔF508 mutation or heterozygous for the G551D mutation were recruited (n = 48). Membrane protein expression was investigated by mass spectrometry. The effect of lung transplantation or ivacaftor therapy was assessed by ELISAs, and calcium fluorometric and μ-calpain assays. Findings Membranes of CF neutrophils contain less cholesterol, yet increased integrin CD11b expression, and respond to inflammatory induced endoplasmic reticulum (ER) stress by activating μ-calpain. In vivo and in vitro, increased μ-calpain activity resulted in proteolysis of the membrane cholesterol trafficking protein caveolin-1. The critical role of caveolin-1 for adequate membrane cholesterol content was confirmed in caveolin-1 knock-out mice. Lung transplant therapy or treatment of PWCF with ivacaftor, reduced levels of circulating inflammatory mediators and actuated increased caveolin-1 and membrane cholesterol, with concurrent normalized neutrophil adhesion. Interpretation Results demonstrate an auxiliary benefit of lung transplant and potentiator therapy, evident by a reduction in circulating inflammation and controlled neutrophil adhesion. This study explored neutrophil adhesion in cystic fibrosis. Altered membrane cholesterol lead to increased adhesion. Circulating inflammatory mediators caused increased calpain activity and reduced membrane cholesterol content.
In patients with cystic fibrosis (CF), chronic inflammation in the circulation, in part originating from the pulmonary compartment, leads to decreased membrane cholesterol in circulating neutrophils, resulting in increased cell adhesion. The mechanism of action involves proteolytic down-regulation of the cholesterol trafficking protein caveolin-1. The overall effect of lung transplant therapy, or CFTR potentiator treatment, was to significantly diminish the circulating inflammatory burden thereby permitting caveolin-1 expression, with concomitant decreased CF cell adhesion and significant clinical improvement.
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Affiliation(s)
- Michelle M White
- Irish Centre for Genetic Lung Disease, Department of Medicine, Royal College of Surgeons in Ireland, Beaumont Hospital, Dublin 9, Ireland
| | - Patrick Geraghty
- Division of Pulmonary & Critical Care Medicine, Department of Medicine, State University of New York Downstate Medical Center, Brooklyn, NY, USA
| | - Elaine Hayes
- Irish Centre for Genetic Lung Disease, Department of Medicine, Royal College of Surgeons in Ireland, Beaumont Hospital, Dublin 9, Ireland
| | - Stephen Cox
- Irish Centre for Genetic Lung Disease, Department of Medicine, Royal College of Surgeons in Ireland, Beaumont Hospital, Dublin 9, Ireland
| | - William Leitch
- Irish Centre for Genetic Lung Disease, Department of Medicine, Royal College of Surgeons in Ireland, Beaumont Hospital, Dublin 9, Ireland
| | - Bader Alfawaz
- Irish Centre for Genetic Lung Disease, Department of Medicine, Royal College of Surgeons in Ireland, Beaumont Hospital, Dublin 9, Ireland
| | - Gillian M Lavelle
- Irish Centre for Genetic Lung Disease, Department of Medicine, Royal College of Surgeons in Ireland, Beaumont Hospital, Dublin 9, Ireland
| | - Oliver J McElvaney
- Irish Centre for Genetic Lung Disease, Department of Medicine, Royal College of Surgeons in Ireland, Beaumont Hospital, Dublin 9, Ireland
| | - Ryan Flannery
- Irish Centre for Genetic Lung Disease, Department of Medicine, Royal College of Surgeons in Ireland, Beaumont Hospital, Dublin 9, Ireland; Coláiste Dhúlaigh College of Further Education, Dublin 17, Ireland
| | - Joanne Keenan
- National Institute for Cellular Biotechnology, Dublin City University, Dublin 9, Ireland
| | - Paula Meleady
- National Institute for Cellular Biotechnology, Dublin City University, Dublin 9, Ireland
| | - Michael Henry
- National Institute for Cellular Biotechnology, Dublin City University, Dublin 9, Ireland
| | - Martin Clynes
- National Institute for Cellular Biotechnology, Dublin City University, Dublin 9, Ireland
| | - Cedric Gunaratnam
- Irish Centre for Genetic Lung Disease, Department of Medicine, Royal College of Surgeons in Ireland, Beaumont Hospital, Dublin 9, Ireland
| | - Noel G McElvaney
- Irish Centre for Genetic Lung Disease, Department of Medicine, Royal College of Surgeons in Ireland, Beaumont Hospital, Dublin 9, Ireland
| | - Emer P Reeves
- Irish Centre for Genetic Lung Disease, Department of Medicine, Royal College of Surgeons in Ireland, Beaumont Hospital, Dublin 9, Ireland.
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16
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Xu Q, Hou YX, Chang XB. CRISPR/Cas9-Mediated Three Nucleotide Insertion Corrects a Deletion Mutation in MRP1/ABCC1 and Restores Its Proper Folding and Function. MOLECULAR THERAPY. NUCLEIC ACIDS 2017. [PMID: 28624219 PMCID: PMC5443964 DOI: 10.1016/j.omtn.2017.05.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
A three-nucleotide deletion in cystic fibrosis transmembrane conductance regulator/ATP-binding cassette transporter C7 (CFTR/ABCC7) resulting in the absence of phenylalanine at 508 leads to mis-fold of the mutated protein and causes cystic fibrosis. We have used a comparable three-nucleotide deletion mutant in another ABCC family member, multidrug resistance-associated protein (MRP1)/ABCC1, to determine whether CRISPR-Cas9-mediated recombination can safely and efficiently knock in three-nucleotide to correct the mutation. We have found that the rate of homology-directed recombination mediated by guideRNA (gRNA) complementary to the deletion mutant is significantly higher than the one mediated by gRNA complementary to the wild-type (WT) donor. In addition, the rate of homology-directed recombination mediated by gRNA complementary to the WT donor is significantly higher than that of gRNAs complementary to the 5' or 3' side of the deletion mutant. Interestingly, the frequency of mutations introduced by gRNA complementary to the deletion mutant is significantly higher than with gRNA complementary to WT donor. However, combination of gRNAs complementary to both WT donor and deletion mutant decreased the rate of homology-directed recombination, but did not significantly decrease the mutation rate introduced by this system. Thus, the data presented here provide guidance for designing of gRNA and donor DNA to do genome editing, especially to correct the mutations with three mismatched nucleotides, such as three-nucleotide deletion or insertion.
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Affiliation(s)
- Qinqin Xu
- Department of Biochemistry & Molecular Biology, College of Medicine, Mayo Clinic in Arizona, Scottsdale, AZ 85259, USA
| | - Yue-Xian Hou
- Department of Biochemistry & Molecular Biology, College of Medicine, Mayo Clinic in Arizona, Scottsdale, AZ 85259, USA
| | - Xiu-Bao Chang
- Department of Biochemistry & Molecular Biology, College of Medicine, Mayo Clinic in Arizona, Scottsdale, AZ 85259, USA.
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17
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Sayyid ZN, Sellers ZM. Technological advances shed light on left ventricular cardiac disturbances in cystic fibrosis. J Cyst Fibros 2017; 16:454-464. [PMID: 28314540 DOI: 10.1016/j.jcf.2017.02.013] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Revised: 02/21/2017] [Accepted: 02/27/2017] [Indexed: 01/08/2023]
Abstract
Cystic fibrosis (CF), the most common autosomal recessive lethal disease in Caucasians, causes chronic pulmonary disease and can lead to cor pulmonale with right ventricular dysfunction. The presence of the cystic fibrosis transmembrane conductance regulator (CFTR) in cardiac myocardia has prompted debate regarding possible defective ion channel-induced cardiomyopathy. Clinical heart disease in CF is considered rare and is restricted to case reports. It has been unclear if this is due to the lack of physiological importance of CFTR in the heart, the relatively short lifespan of those with CF, or a technical inability to detect subclinical disease. Extensive echocardiographic investigations have yielded contradictory results, leading to the dogma that left ventricular defects in CF occur secondary to lung disease. In this review, we consider why studies examining heart function in CF have not provided clarity on this topic. We then focus on data from new echocardiographic and magnetic resonance imaging technology, which are providing greater insight into cardiac function in CF and demonstrating that, in addition to secondary effects from pulmonary disease, there may be an intrinsic primary defect in the CF heart. With advancing lifespans and activity levels, understanding the risk of cardiac disease is vital to minimizing morbidity in adults with CF.
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Affiliation(s)
- Zahra N Sayyid
- Stanford University, School of Medicine, Palo Alto, CA, United States
| | - Zachary M Sellers
- Stanford University, School of Medicine, Palo Alto, CA, United States.
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18
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Rymut SM, Kampman CM, Corey DA, Endres T, Cotton CU, Kelley TJ. Ibuprofen regulation of microtubule dynamics in cystic fibrosis epithelial cells. Am J Physiol Lung Cell Mol Physiol 2016; 311:L317-27. [PMID: 27317686 DOI: 10.1152/ajplung.00126.2016] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2016] [Accepted: 06/12/2016] [Indexed: 11/22/2022] Open
Abstract
High-dose ibuprofen, an effective anti-inflammatory therapy for the treatment of cystic fibrosis (CF), has been shown to preserve lung function in a pediatric population. Despite its efficacy, few patients receive ibuprofen treatment due to potential renal and gastrointestinal toxicity. The mechanism of ibuprofen efficacy is also unclear. We have previously demonstrated that CF microtubules are slower to reform after depolymerization compared with respective wild-type controls. Slower microtubule dynamics in CF cells are responsible for impaired intracellular transport and are related to inflammatory signaling. Here, it is identified that high-dose ibuprofen treatment in both CF cell models and primary CF nasal epithelial cells restores microtubule reformation rates to wild-type levels, as well as induce extension of microtubules to the cell periphery. Ibuprofen treatment also restores microtubule-dependent intracellular transport monitored by measuring intracellular cholesterol transport. These effects are specific to ibuprofen as other cyclooxygenase inhibitors have no effect on these measures. Effects of ibuprofen are mimicked by stimulation of AMPK and blocked by the AMPK inhibitor compound C. We conclude that high-dose ibuprofen treatment enhances microtubule formation in CF cells likely through an AMPK-related pathway. These findings define a potential mechanism to explain the efficacy of ibuprofen therapy in CF.
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Affiliation(s)
- Sharon M Rymut
- Departments of Pediatrics, Case Western Reserve University, Cleveland, Ohio
| | - Claire M Kampman
- Departments of Pediatrics, Case Western Reserve University, Cleveland, Ohio
| | - Deborah A Corey
- Departments of Pediatrics, Case Western Reserve University, Cleveland, Ohio
| | - Tori Endres
- Departments of Pediatrics, Case Western Reserve University, Cleveland, Ohio
| | - Calvin U Cotton
- Departments of Pediatrics, Case Western Reserve University, Cleveland, Ohio
| | - Thomas J Kelley
- Departments of Pediatrics, Case Western Reserve University, Cleveland, Ohio
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19
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Kucera A, Borg Distefano M, Berg-Larsen A, Skjeldal F, Repnik U, Bakke O, Progida C. Spatiotemporal Resolution of Rab9 and CI-MPR Dynamics in the Endocytic Pathway. Traffic 2016; 17:211-29. [PMID: 26663757 DOI: 10.1111/tra.12357] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2015] [Revised: 12/08/2015] [Accepted: 12/08/2015] [Indexed: 12/21/2022]
Abstract
Rab9 is a small GTPase that localizes to the trans-Golgi Network (TGN) and late endosomes. Its main function has long been connected to the recycling of mannose-6-phosphate receptors (MPRs). However, recent studies link Rab9 also to autophagy and lysosome biogenesis. In this paper, using confocal imaging, we characterize for the first time the live dynamics of the Rab9 constitutively active mutant, Rab9Q66L. We find that it localizes predominantly to late endosomes and that its expression in HeLa cells disperses TGN46 and cation-independent (CI-MPR) away from the Golgi yet, has no effect on the retrograde transport of CI-MPR. We also show that CI-MPR and Rab9 enter the endosomal pathway together at the transition stage between early, Rab5-positive, and late, Rab7a-positive, endosomes. CI-MPR localizes transiently to separate domains on these endosomes, where vesicles carrying CI-MPR attach and detach within seconds. Taken together, our results demonstrate that Rab9 mediates the delivery of CI-MPR to the endosomal pathway, entering the maturing endosome at the early-to-late transition.
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Affiliation(s)
- Ana Kucera
- Department of Biosciences, Centre for Immune Regulation, University of Oslo, Oslo, Norway
| | - Marita Borg Distefano
- Department of Biosciences, Centre for Immune Regulation, University of Oslo, Oslo, Norway
| | - Axel Berg-Larsen
- Department of Biosciences, Centre for Immune Regulation, University of Oslo, Oslo, Norway.,Current address: Department of Cancer Immunology, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway
| | - Frode Skjeldal
- Department of Biosciences, Centre for Immune Regulation, University of Oslo, Oslo, Norway
| | - Urska Repnik
- Department of Biosciences, Centre for Immune Regulation, University of Oslo, Oslo, Norway
| | - Oddmund Bakke
- Department of Biosciences, Centre for Immune Regulation, University of Oslo, Oslo, Norway
| | - Cinzia Progida
- Department of Biosciences, Centre for Immune Regulation, University of Oslo, Oslo, Norway
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20
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Ernst WL, Shome K, Wu CC, Gong X, Frizzell RA, Aridor M. VAMP-associated Proteins (VAP) as Receptors That Couple Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) Proteostasis with Lipid Homeostasis. J Biol Chem 2016; 291:5206-20. [PMID: 26740627 DOI: 10.1074/jbc.m115.692749] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Indexed: 12/27/2022] Open
Abstract
Unesterified cholesterol accumulates in late endosomes in cells expressing the misfolded cystic fibrosis transmembrane conductance regulator (CFTR). CFTR misfolding in the endoplasmic reticulum (ER) or general activation of ER stress led to dynein-mediated clustering of cholesterol-loaded late endosomes at the Golgi region, a process regulated by ER-localized VAMP-associated proteins (VAPs). We hypothesized that VAPs serve as intracellular receptors that couple lipid homeostasis through interactions with two phenylalanines in an acidic track (FFAT) binding signals (found in lipid sorting and sensing proteins, LSS) with proteostasis regulation. VAPB inhibited the degradation of ΔF508-CFTR. The activity was mapped to the ligand-binding major sperm protein (MSP) domain, which was sufficient in regulating CFTR biogenesis. We identified mutations in an unstructured loop within the MSP that uncoupled VAPB-regulated CFTR biogenesis from basic interactions with FFAT. Using this information, we defined functional and physical interactions between VAPB and proteostasis regulators (ligands), including the unfolded protein response sensor ATF6 and the ER degradation cluster that included FAF1, VCP, BAP31, and Derlin-1. VAPB inhibited the degradation of ΔF508-CFTR in the ER through interactions with the RMA1-Derlin-BAP31-VCP pathway. Analysis of pseudoligands containing tandem FFAT signals supports a competitive model for VAP interactions that direct CFTR biogenesis. The results suggest a model in which VAP-ligand binding couples proteostasis and lipid homeostasis leading to observed phenotypes of lipid abnormalities in protein folding diseases.
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Affiliation(s)
- Wayne L Ernst
- From the Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15261
| | - Kuntala Shome
- From the Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15261
| | - Christine C Wu
- From the Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15261
| | - Xiaoyan Gong
- From the Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15261
| | - Raymond A Frizzell
- From the Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15261
| | - Meir Aridor
- From the Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15261
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21
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Wei S, Roessler BC, Icyuz M, Chauvet S, Tao B, Hartman JL, Kirk KL. Long-range coupling between the extracellular gates and the intracellular ATP binding domains of multidrug resistance protein pumps and cystic fibrosis transmembrane conductance regulator channels. FASEB J 2015; 30:1247-62. [PMID: 26606940 DOI: 10.1096/fj.15-278382] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Accepted: 11/16/2015] [Indexed: 12/22/2022]
Abstract
The ABCC transporter subfamily includes pumps, the long and short multidrug resistance proteins (MRPs), and an ATP-gated anion channel, the cystic fibrosis transmembrane conductance regulator (CFTR). We show that despite their thermodynamic differences, these ABCC transporter subtypes use broadly similar mechanisms to couple their extracellular gates to the ATP occupancies of their cytosolic nucleotide binding domains. A conserved extracellular phenylalanine at this gate was a prime location for producing gain of function (GOF) mutants of a long MRP in yeast (Ycf1p cadmium transporter), a short yeast MRP (Yor1p oligomycin exporter), and human CFTR channels. Extracellular gate mutations rescued ATP binding mutants of the yeast MRPs and CFTR by increasing ATP sensitivity. Control ATPase-defective MRP mutants could not be rescued by this mechanism. A CFTR double mutant with an extracellular gate mutation plus a cytosolic GOF mutation was highly active (single-channel open probability >0.3) in the absence of ATP and protein kinase A, each normally required for CFTR activity. We conclude that all 3 ABCC transporter subtypes use similar mechanisms to couple their extracellular gates to ATP occupancy, and highly active CFTR channels that bypass defects in ATP binding or phosphorylation can be produced.
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Affiliation(s)
- Shipeng Wei
- *Department of Cell, Developmental, and Integrative Biology, Department of Genetics, and Department of Neurobiology, Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Bryan C Roessler
- *Department of Cell, Developmental, and Integrative Biology, Department of Genetics, and Department of Neurobiology, Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Mert Icyuz
- *Department of Cell, Developmental, and Integrative Biology, Department of Genetics, and Department of Neurobiology, Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Sylvain Chauvet
- *Department of Cell, Developmental, and Integrative Biology, Department of Genetics, and Department of Neurobiology, Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Binli Tao
- *Department of Cell, Developmental, and Integrative Biology, Department of Genetics, and Department of Neurobiology, Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - John L Hartman
- *Department of Cell, Developmental, and Integrative Biology, Department of Genetics, and Department of Neurobiology, Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Kevin L Kirk
- *Department of Cell, Developmental, and Integrative Biology, Department of Genetics, and Department of Neurobiology, Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham, Birmingham, Alabama, USA
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Reverri EJ, Morrissey BM, Cross CE, Steinberg FM. Inflammation, oxidative stress, and cardiovascular disease risk factors in adults with cystic fibrosis. Free Radic Biol Med 2014; 76:261-77. [PMID: 25172163 DOI: 10.1016/j.freeradbiomed.2014.08.005] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2013] [Revised: 07/31/2014] [Accepted: 08/05/2014] [Indexed: 12/21/2022]
Abstract
Cystic fibrosis (CF) represents one of a number of localized lung and non-lung diseases with an intense chronic inflammatory component associated with evidence of systemic oxidative stress. Many of these chronic inflammatory diseases are accompanied by an array of atherosclerotic processes and cardiovascular disease (CVD), another condition strongly related to inflammation and oxidative stress. As a consequence of a dramatic increase in long-lived patients with CF in recent decades, the specter of CVD must be considered in these patients who are now reaching middle age and beyond. Buttressed by recent data documenting that CF patients exhibit evidence of endothelial dysfunction, a recognized precursor of atherosclerosis and CVD, the spectrum of risk factors for CVD in CF is reviewed here. Epidemiological data further characterizing the presence and extent of atherogenic processes in CF patients would seem important to obtain. Such studies should further inform and offer mechanistic insights into how other chronic inflammatory diseases potentiate the processes leading to CVDs.
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Affiliation(s)
- Elizabeth J Reverri
- Department of Nutrition, University of California Davis, One Shields Avenue, 3135 Meyer Hall, Davis, CA 95616, USA
| | - Brian M Morrissey
- Adult Cystic Fibrosis Clinic and Division of Pulmonary-Critical Care Medicine, University of California Davis Medical Center, 4150 V Street, Sacramento, CA 95817, USA
| | - Carroll E Cross
- Adult Cystic Fibrosis Clinic and Division of Pulmonary-Critical Care Medicine, University of California Davis Medical Center, 4150 V Street, Sacramento, CA 95817, USA.
| | - Francene M Steinberg
- Department of Nutrition, University of California Davis, One Shields Avenue, 3135 Meyer Hall, Davis, CA 95616, USA
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Smerieri A, Montanini L, Maiuri L, Bernasconi S, Street ME. FOXO1 content is reduced in cystic fibrosis and increases with IGF-I treatment. Int J Mol Sci 2014; 15:18000-22. [PMID: 25299696 PMCID: PMC4227201 DOI: 10.3390/ijms151018000] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2014] [Revised: 09/02/2014] [Accepted: 09/22/2014] [Indexed: 12/27/2022] Open
Abstract
Cystic fibrosis-related diabetes is to date the most frequent complication in cystic fibrosis (CF). The mechanisms underlying this condition are not well understood, and a possible role of insulin resistance is debated. We investigated insulin signal transduction in CF. Total insulin receptor, IRS1, p85 PI3K, and AKT contents were substantially normal in CF cells (CFBE41o-), whereas winged helix forkhead (FOX)O1 contents were reduced both in baseline conditions and after insulin stimulation. In addition, CF cells showed increased ERK1/2, and reduced β2 arrestin contents. No significant change in SOCS2 was observed. By using a CFTR inhibitor and siRNA, changes in FOXO1 were related to CFTR loss of function. In a CF-affected mouse model, FOXO1 content was reduced in the muscle while no significant difference was observed in liver and adipose tissue compared with wild-type. Insulin-like growth factor 1 (IGF-I) increased FOXO1 content in vitro and in vivo in muscle and adipose tissue. In conclusion; we present the first description of reduced FOXO1 content in CF, which is compatible with reduced gluconeogenesis and increased adipogenesis, both features of insulin insensitivity. IGF-I treatment was effective in increasing FOXO1, thereby suggesting that it could be considered as a potential treatment in CF patients possibly to prevent and treat cystic fibrosis-related diabetes.
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Affiliation(s)
- Arianna Smerieri
- Department of Pediatrics, University Hospital of Parma, Via Gramsci 14, 43126 Parma, Italy.
| | - Luisa Montanini
- Department of Pediatrics, University Hospital of Parma, Via Gramsci 14, 43126 Parma, Italy.
| | - Luigi Maiuri
- European Institute for Research in Cystic Fibrosis, San Raffaele Scientific Institute, Via Olgettina 60, 20132 Milan, Italy.
| | - Sergio Bernasconi
- Department of Pediatrics, University Hospital of Parma, Via Gramsci 14, 43126 Parma, Italy.
| | - Maria E Street
- Department of Pediatrics, University Hospital of Parma, Via Gramsci 14, 43126 Parma, Italy.
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Wei S, Roessler BC, Chauvet S, Guo J, Hartman JL, Kirk KL. Conserved allosteric hot spots in the transmembrane domains of cystic fibrosis transmembrane conductance regulator (CFTR) channels and multidrug resistance protein (MRP) pumps. J Biol Chem 2014; 289:19942-57. [PMID: 24876383 DOI: 10.1074/jbc.m114.562116] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
ATP-binding cassette (ABC) transporters are an ancient family of transmembrane proteins that utilize ATPase activity to move substrates across cell membranes. The ABCC subfamily of the ABC transporters includes active drug exporters (the multidrug resistance proteins (MRPs)) and a unique ATP-gated ion channel (cystic fibrosis transmembrane conductance regulator (CFTR)). The CFTR channel shares gating principles with conventional ligand-gated ion channels, but the allosteric network that couples ATP binding at its nucleotide binding domains (NBDs) with conformational changes in its transmembrane helices (TMs) is poorly defined. It is also unclear whether the mechanisms that govern CFTR gating are conserved with the thermodynamically distinct MRPs. Here we report a new class of gain of function (GOF) mutation of a conserved proline at the base of the pore-lining TM6. Multiple substitutions of this proline promoted ATP-free CFTR activity and activation by the weak agonist, 5'-adenylyl-β,γ-imidodiphosphate (AMP-PNP). TM6 proline mutations exhibited additive GOF effects when combined with a previously reported GOF mutation located in an outer collar of TMs that surrounds the pore-lining TMs. Each TM substitution allosterically rescued the ATP sensitivity of CFTR gating when introduced into an NBD mutant with defective ATP binding. Both classes of GOF mutations also rescued defective drug export by a yeast MRP (Yor1p) with ATP binding defects in its NBDs. We conclude that the conserved TM6 proline helps set the energy barrier to both CFTR channel opening and MRP-mediated drug efflux and that CFTR channels and MRP pumps utilize similar allosteric mechanisms for coupling conformational changes in their translocation pathways to ATP binding at their NBDs.
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Affiliation(s)
- Shipeng Wei
- From the Departments of Cell, Developmental, and Integrative Biology
| | - Bryan C Roessler
- From the Departments of Cell, Developmental, and Integrative Biology
| | - Sylvain Chauvet
- From the Departments of Cell, Developmental, and Integrative Biology
| | | | | | - Kevin L Kirk
- From the Departments of Cell, Developmental, and Integrative Biology, Neurobiology and the Gregory Fleming James Cystic Fibrosis Research Center, University of Alabama at Birmingham, Birmingham Alabama 35294-0005
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25
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Eckford P, Ramjeesingh M, Molinski S, Pasyk S, Dekkers JF, Li C, Ahmadi S, Ip W, Chung T, Du K, Yeger H, Beekman J, Gonska T, Bear C. VX-809 and Related Corrector Compounds Exhibit Secondary Activity Stabilizing Active F508del-CFTR after Its Partial Rescue to the Cell Surface. ACTA ACUST UNITED AC 2014; 21:666-78. [DOI: 10.1016/j.chembiol.2014.02.021] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2013] [Revised: 02/22/2014] [Accepted: 02/25/2014] [Indexed: 12/11/2022]
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27
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van Meegen MA, Terheggen SWJ, Koymans KJ, Vijftigschild LAW, Dekkers JF, van der Ent CK, Beekman JM. CFTR-mutation specific applications of CFTR-directed monoclonal antibodies. J Cyst Fibros 2013; 12:487-96. [PMID: 23317763 DOI: 10.1016/j.jcf.2012.12.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2012] [Revised: 12/01/2012] [Accepted: 12/11/2012] [Indexed: 11/18/2022]
Abstract
BACKGROUND Over the last decade novel monoclonal CFTR-specific antibodies have been developed. We here present a paired analysis to detect wild-type and mutant CFTR using Western blot analysis, flow cytometry and confocal microscopy in several cellular expression systems. METHODS The following CFTR-specific antibodies were used; 217, 432, 450, 570, 769, 596, 660, L12B4 and 24.1. Mutant CFTR was detected in HEK293 cells transiently expressing the mutations; G542X, R1162X, F508del, N1303K, G551D, R117H, A455E. RESULTS The majority of these antibodies are suitable for most applications tested. Using immunofluorescence, some antibodies can better detect mutant forms of CFTR (F508del and N1303K by mAbs 596 and 769), or display lower aspecific detection by Western blot analysis (mAbs 432, 450, 769 and 596) or immunofluorescence (mAbs 432, 450, 570 and 769). CONCLUSION Optimal detection of CFTR by monoclonal antibodies depends on CFTR mutation and the specific research application.
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Affiliation(s)
- M A van Meegen
- Department of Pediatric Pulmonology, University Medical Centre Utrecht, The Netherlands
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Molinski S, Eckford PDW, Pasyk S, Ahmadi S, Chin S, Bear CE. Functional Rescue of F508del-CFTR Using Small Molecule Correctors. Front Pharmacol 2012; 3:160. [PMID: 23055971 PMCID: PMC3458236 DOI: 10.3389/fphar.2012.00160] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2012] [Accepted: 08/17/2012] [Indexed: 01/21/2023] Open
Abstract
High-throughput screens for small molecules that are effective in “correcting” the functional expression of F508del-CFTR have yielded several promising hits. Two such compounds are currently in clinical trial. Despite this success, it is clear that further advances will be required in order to restore 50% or greater of wild-type CFTR function to the airways of patients harboring the F508del-CFTR protein. Progress will be enhanced by our better understanding of the molecular and cellular defects caused by the F508del mutation, present in 90% of CF patients. The goal of this chapter is to review the current understanding of defects caused by F508del in the CFTR protein and in CFTR-mediated interactions important for its biosynthesis, trafficking, channel function, and stability at the cell surface. Finally, we will discuss the gaps in our knowledge regarding the mechanism of action of existing correctors, the unmet need to discover compounds which restore proper CFTR structure and function in CF affected tissues and new strategies for therapy development.
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Affiliation(s)
- Steven Molinski
- Programme in Molecular Structure and Function, Research Institute, Hospital for Sick Children Toronto, ON, Canada ; Department of Biochemistry, University of Toronto Toronto, ON, Canada
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29
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Manson ME, Corey DA, Bederman I, Burgess JD, Kelley TJ. Regulatory role of β-arrestin-2 in cholesterol processing in cystic fibrosis epithelial cells. J Lipid Res 2012; 53:1268-76. [PMID: 22523395 DOI: 10.1194/jlr.m021972] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Cystic fibrosis (CF) cells exhibit an increase in the protein expression of β-arrestin-2 (βarr2) coincident with perinuclear accumulation of free cholesterol. Arrestins are proteins that both serve as broad signaling regulators and contribute to G-protein coupled receptor internalization after agonist stimulation. The hypothesis of this study is that βarr2 is an important component in the mechanisms leading to cholesterol accumulation characteristic of CF cells. To test this hypothesis, epithelial cells stably expressing GFP-tagged βarr2 (βarr2-GFP) and respective GFP-expressing control cells (cont-GFP) were analyzed by filipin staining. The βarr2-GFP cells show a late endosomal/lysosomal cholesterol accumulation that is identical to that seen in CF cells. This βarr2-mediated accumulation is sensitive to Rp-cAMPS treatment, and depleting βarr2 expression in CF-model cells by shRNA alleviates cholesterol accumulation compared with controls. Cftr/βarr2 double knockout mice also exhibit wild-type (WT) levels of cholesterol synthesis, and WT profiles of signaling protein expression have previously been shown to be altered in CF due to cholesterol-related pathways. These data indicate a significant regulatory role for βarr2 in the development of CF-like cholesterol accumulation and give further insight into cholesterol processing mechanisms. An impact of βarr2 expression on Niemann-Pick type C-1 (NPC1)-containing organelle movement is proposed as the mechanism of βarr2-mediated alterations on cholesterol processing. It is concluded that βarr2 expression contributes to altered cholesterol trafficking observed in CF cells.
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Affiliation(s)
- Mary E Manson
- Departments of Chemistry, Case Western Reserve University, Cleveland, OH, USA
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30
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Abstract
Uromodulin is exclusively expressed in the thick ascending limb and is the most abundant protein secreted in urine where it is found in high-molecular-weight polymers. Its biological functions are still elusive, but it is thought to play a protective role against urinary tract infection, calcium oxalate crystal formation, and regulation of water and salt balance in the thick ascending limb. Mutations in uromodulin are responsible for autosomal-dominant kidney diseases characterized by defective urine concentrating ability, hyperuricemia, gout, tubulointerstitial fibrosis, renal cysts, and chronic kidney disease. Previous in vitro studies found retention in the endoplasmic reticulum as a common feature of all uromodulin mutant isoforms. Both in vitro and in vivo we found that mutant isoforms partially escaped retention in the endoplasmic reticulum and reached the plasma membrane where they formed large extracellular aggregates that have a dominant-negative effect on coexpressed wild-type protein. Notably, mutant uromodulin excretion was detected in patients carrying uromodulin mutations. Thus, our results suggest that mutant uromodulin exerts a gain-of-function effect that can be exerted by both intra- and extracellular forms of the protein.
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31
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Cianciola NL, Carlin CR, Kelley TJ. Molecular pathways for intracellular cholesterol accumulation: common pathogenic mechanisms in Niemann-Pick disease Type C and cystic fibrosis. Arch Biochem Biophys 2011; 515:54-63. [PMID: 21924233 PMCID: PMC3192251 DOI: 10.1016/j.abb.2011.08.012] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2011] [Revised: 08/29/2011] [Accepted: 08/30/2011] [Indexed: 12/11/2022]
Abstract
It has been less than two decades since the underlying genetic defects in Niemann-Pick disease Type C were first identified. These defects impair function of two proteins with a direct role in lipid trafficking, resulting in deposition of free cholesterol within late endosomal compartments and a multitude of effects on cell function and clinical manifestations. The rapid pace of research in this area has vastly improved our overall understanding of intracellular cholesterol homeostasis. Excessive cholesterol buildup has also been implicated in clinical manifestations associated with a number of genetically unrelated diseases including cystic fibrosis. Applying knowledge about anomalous cell signaling behavior in cystic fibrosis opens prospects for identifying similar previously unrecognized disease pathways in Niemann-Pick disease Type C. Recognition that Niemann-Pick disease Type C and cystic fibrosis both impair cholesterol regulatory pathways also provides a rationale for identifying common therapeutic targets.
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Affiliation(s)
- Nicholas L. Cianciola
- Department of Molecular Biology and Microbiology, School of Medicine, Case Western Reserve University, Cleveland, Ohio 44106-4970
| | - Cathleen R. Carlin
- Department of Molecular Biology and Microbiology, School of Medicine, Case Western Reserve University, Cleveland, Ohio 44106-4970
- Case Western Reserve University Comprehensive Cancer Center, School of Medicine, Case Western Reserve University, Cleveland, Ohio 44106-4970
| | - Thomas J. Kelley
- Department of Pediatrics, School of Medicine, Case Western Reserve University, Cleveland, Ohio 44106-4970
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Abstract
The combination of carbohydrate and lipid generates unusual molecules in which the two distinctive halves of the glycoconjugate influence the function of each other. Membrane glycolipids can act as primary receptors for carbohydrate binding proteins to mediate transmembrane signaling despite restriction to the outer bilayer leaflet. The extensive heterogeneity of the lipid moiety plays a significant, but still largely unknown, role in glycosphingolipid function. Potential interplay between glycolipids and their fatty acid isoforms, together with their preferential interaction with cholesterol, generates a complex mechanism for the regulation of their function in cellular physiology.
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Affiliation(s)
- Clifford A Lingwood
- Research Institute, Hospital for Sick Children, Molecular Structure and Function, Toronto, Ontario M5G 1X8, Canada.
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34
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Watson MJ, Worthington EN, Clunes LA, Rasmussen JE, Jones L, Tarran R. Defective adenosine-stimulated cAMP production in cystic fibrosis airway epithelia: a novel role for CFTR in cell signaling. FASEB J 2011; 25:2996-3003. [PMID: 21628448 DOI: 10.1096/fj.11-186080] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Adenosine (ADO) is an extracellular signaling molecule that is an important regulator of innate lung defense. On binding ADO, the A2B receptor (A2BR) stimulates cAMP production to activate the CFTR Cl(-) channel, increase ciliary beating, and initiate cytokine secretion. We tested the hypothesis that CFTR served as a positive regulator of the A2BRs. We found that A2BR and CFTR coimmunoprecipitated. They also underwent ADO-dependent Förster resonance energy transfer (FRET), which increased from 5% in the absence of agonist to 18% with 100 μM ADO (EC₅₀ 1.7 μM), suggesting that they dynamically associate in the plasma membrane. In contrast, despite colocalization, no FRET was observed between CFTR and GAP43. The interaction between A2BR and CFTR had some specificity: A2BR-stimulated but not forskolin-stimulated cAMP production was ~50% greater in the presence of CFTR, due to a CFTR-dependent increase in plasma membrane A2BR levels. These CFTR-dependent increases in A2BR levels and cAMP production resulted in significantly enhanced ciliary beating and increased cytokine secretion in normal compared to cystic fibrosis airway epithelia. Thus, we hypothesize that CFTR regulates A2BR levels in the plasma membrane to modulate cell signaling and to enhance selective components of the innate lung defense system.
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Affiliation(s)
- Michael J Watson
- Cystic Fibrosis/Pulmonary Research and Treatment Center, The University of North Carolina, Chapel Hill, NC 27599-7248, USA
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Johnson JS, Gentzsch M, Zhang L, Ribeiro CMP, Kantor B, Kafri T, Pickles RJ, Samulski RJ. AAV exploits subcellular stress associated with inflammation, endoplasmic reticulum expansion, and misfolded proteins in models of cystic fibrosis. PLoS Pathog 2011; 7:e1002053. [PMID: 21625534 PMCID: PMC3098238 DOI: 10.1371/journal.ppat.1002053] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2011] [Accepted: 03/16/2011] [Indexed: 12/11/2022] Open
Abstract
Barriers to infection act at multiple levels to prevent viruses, bacteria, and parasites from commandeering host cells for their own purposes. An intriguing hypothesis is that if a cell experiences stress, such as that elicited by inflammation, endoplasmic reticulum (ER) expansion, or misfolded proteins, then subcellular barriers will be less effective at preventing viral infection. Here we have used models of cystic fibrosis (CF) to test whether subcellular stress increases susceptibility to adeno-associated virus (AAV) infection. In human airway epithelium cultured at an air/liquid interface, physiological conditions of subcellular stress and ER expansion were mimicked using supernatant from mucopurulent material derived from CF lungs. Using this inflammatory stimulus to recapitulate stress found in diseased airways, we demonstrated that AAV infection was significantly enhanced. Since over 90% of CF cases are associated with a misfolded variant of Cystic Fibrosis Transmembrane Conductance Regulator (ΔF508-CFTR), we then explored whether the presence of misfolded proteins could independently increase susceptibility to AAV infection. In these models, AAV was an order of magnitude more efficient at transducing cells expressing ΔF508-CFTR than in cells expressing wild-type CFTR. Rescue of misfolded ΔF508-CFTR under low temperature conditions restored viral transduction efficiency to that demonstrated in controls, suggesting effects related to protein misfolding were responsible for increasing susceptibility to infection. By testing other CFTR mutants, G551D, D572N, and 1410X, we have shown this phenomenon is common to other misfolded proteins and not related to loss of CFTR activity. The presence of misfolded proteins did not affect cell surface attachment of virus or influence expression levels from promoter transgene cassettes in plasmid transfection studies, indicating exploitation occurs at the level of virion trafficking or processing. Thus, we surmised that factors enlisted to process misfolded proteins such as ΔF508-CFTR in the secretory pathway also act to restrict viral infection. In line with this hypothesis, we found that AAV trafficked to the microtubule organizing center and localized near Golgi/ER transport proteins. Moreover, AAV infection efficiency could be modulated with siRNA-mediated knockdown of proteins involved in processing ΔF508-CFTR or sorting retrograde cargo from the Golgi and ER (calnexin, KDEL-R, β-COP, and PSMB3). In summary, our data support a model where AAV exploits a compromised secretory system and, importantly, underscore the gravity with which a stressed subcellular environment, under internal or external insults, can impact infection efficiency. Misfolded proteins have been associated with a variety of disorders such as cystic fibrosis, diabetes insipidus, alpha-antitrypsin deficiency, Parkinson's disease, and cancer. In this study, by using cellular models of events in cystic fibrosis lung disease we have revealed an effect of misfolded proteins on increasing susceptibility to infection with a parvovirus. Infection efficiency was an order of magnitude higher in cells expressing misfolded Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) mutant proteins than in cells expressing the correctly folded protein. During infection, virus capsids accumulated near cellular factors that normally process misfolded proteins and are involved in retrograde trafficking from the Golgi to endoplasmic reticulum. Furthermore, we have demonstrated that infection efficiency can be attenuated by restoring correct protein folding or augmented by siRNA-mediated knockdown of secretory pathway components. Taken together our results indicate that converging cellular systems operate to clear misfolded proteins and virus capsids from an infected cell. We raise the possibility that parvoviruses and perhaps other viruses exploit congested cellular secretory pathways during entry, and that viral infection could be a contributing factor in the progression of diseases associated with misfolded proteins.
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Affiliation(s)
- Jarrod S Johnson
- Department of Pharmacology, University of North Carolina, Chapel Hill, North Carolina, United States of America.
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36
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Bruscia EM, Zhang PX, Satoh A, Caputo C, Medzhitov R, Shenoy A, Egan ME, Krause DS. Abnormal trafficking and degradation of TLR4 underlie the elevated inflammatory response in cystic fibrosis. THE JOURNAL OF IMMUNOLOGY 2011; 186:6990-8. [PMID: 21593379 DOI: 10.4049/jimmunol.1100396] [Citation(s) in RCA: 110] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Morbidity and mortality in cystic fibrosis (CF) are due not only to abnormal epithelial cell function, but also to an abnormal immune response. We have shown previously that macrophages lacking CF transmembrane conductance regulator (CFTR), the gene mutated in CF, contribute significantly to the hyperinflammatory response observed in CF. In this study, we show that lack of functional CFTR in murine macrophages causes abnormal TLR4 subcellular localization. Upon LPS stimulation, CFTR macrophages have prolonged TLR4 retention in the early endosome and reduced translocation into the lysosomal compartment. This abnormal TLR4 trafficking leads to increased LPS-induced activation of the NF-κB, MAPK, and IFN regulatory factor-3 pathways and decreased TLR4 degradation, which affects downregulation of the proinflammatory state. In addition to primary murine cells, mononuclear cells isolated from CF patients demonstrate similar defects in response to LPS. Moreover, specific inhibition of CFTR function induces abnormal TLR4 trafficking and enhances the inflammatory response of wild-type murine cells to LPS. Thus, functional CFTR in macrophages influences TLR4 spatial and temporal localization and perturbs LPS-mediated signaling in both murine CF models and patients with CF.
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Affiliation(s)
- Emanuela M Bruscia
- Department of Pediatrics, Yale University School of Medicine, New Haven, CT 06509, USA.
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Faria D, Dahimène S, Alessio L, Scott-Ward T, Schreiber R, Kunzelmann K, Amaral MD. Effect of Annexin A5 on CFTR: regulated traffic or scaffolding? Mol Membr Biol 2010; 28:14-29. [PMID: 21067452 DOI: 10.3109/09687688.2010.506264] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Previous studies have implicated annexins in regulating ion channels and in particular annexin A5 (AnxA5) in the traffic of the cystic fibrosis transmembrane conductance regulator (CFTR). In the present study, we further investigated the role of AnxA5 in regulating CFTR function and intracellular trafficking in both Xenopus oocytes and mammalian cells. Although we could confirm the previously reported CFTR/AnnxA5 interaction, we found that in oocytes AnxA5 inhibits CFTR-mediated whole-cell membrane conductance presumably by a mechanism independent of PDZ-binding domain at the C-terminus of CFTR but protein kinase C (PKC)-dependent and results from either endocytosis activation and/or exocytosis block. In contrast, in human cells, co-expression of AnxA5 augmented CFTR whole-cell currents, an effect that was independent of CFTR PDZ-binding domain. We conclude that annexin A5 has multiple effects on CFTR, so that the net effect observed is cell system-dependent. Nevertheless, both effects observed here are consistent with the described role of annexins forming scaffolding platforms at cell membranes, thus contributing to a decrease in their dynamics. Finally, we could not confirm that AnxA5 overexpression rescues traffic/function of the most frequent disease-causing mutant F508del-CFTR, thus concluding that AnxA5 is not a promising tool for correction of the F508del-CFTR defect.
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Affiliation(s)
- Diana Faria
- Department of Physiology, University of Regensburg, Germany
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Kalid O, Mense M, Fischman S, Shitrit A, Bihler H, Ben-Zeev E, Schutz N, Pedemonte N, Thomas PJ, Bridges RJ, Wetmore DR, Marantz Y, Senderowitz H. Small molecule correctors of F508del-CFTR discovered by structure-based virtual screening. J Comput Aided Mol Des 2010; 24:971-91. [PMID: 20976528 DOI: 10.1007/s10822-010-9390-0] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2010] [Accepted: 10/06/2010] [Indexed: 10/18/2022]
Abstract
Folding correctors of F508del-CFTR were discovered by in silico structure-based screening utilizing homology models of CFTR. The intracellular segment of CFTR was modeled and three cavities were identified at inter-domain interfaces: (1) Interface between the two Nucleotide Binding Domains (NBDs); (2) Interface between NBD1 and Intracellular Loop (ICL) 4, in the region of the F508 deletion; (3) multi-domain interface between NBD1:2:ICL1:2:4. We hypothesized that compounds binding at these interfaces may improve the stability of the protein, potentially affecting the folding yield or surface stability. In silico structure-based screening was performed at the putative binding-sites and a total of 496 candidate compounds from all three sites were tested in functional assays. A total of 15 compounds, representing diverse chemotypes, were identified as F508del folding correctors. This corresponds to a 3% hit rate, ~tenfold higher than hit rates obtained in corresponding high-throughput screening campaigns. The same binding sites also yielded potentiators and, most notably, compounds with a dual corrector-potentiator activity (dual-acting). Compounds harboring both activity types may prove to be better leads for the development of CF therapeutics than either pure correctors or pure potentiators. To the best of our knowledge this is the first report of structure-based discovery of CFTR modulators.
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Affiliation(s)
- Ori Kalid
- EPIX Pharmaceuticals Ltd., 3 Hayetzira Street, Ramat Gan, Israel.
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Strandvik B. Fatty acid metabolism in cystic fibrosis. Prostaglandins Leukot Essent Fatty Acids 2010; 83:121-9. [PMID: 20673710 DOI: 10.1016/j.plefa.2010.07.002] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/29/2010] [Accepted: 07/07/2010] [Indexed: 12/23/2022]
Abstract
Despite identification twenty years ago of the gene responsible for cystic fibrosis transmembrane conductance regulator (CFTR), the protein defective in cystic fibrosis (CF), research of this monogenetic disease has not provided an explanation for the divergent symptoms, and a treatment breakthrough is still awaited. This review discusses different aspects of disturbances in lipid metabolism seen in CF. These include increased release of arachidonic acid (AA) from cell membrane phospholipids and a low status of linoleic and docosahexaenoic acids. Recent research has explored more complicated lipid associations. Disturbances in annexins and ceramides might act in concert to explain the impact on inflammation and AA release. The connections to CFTR and between the disturbances in essential fatty acid metabolism are reviewed. The metabolic interactions, some of which might be compensating, possibly explain the difficulties in understanding the fatty acid disturbances in relation to different symptoms and their relation to the defective CFTR.
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Affiliation(s)
- Birgitta Strandvik
- Department of Biosciences and Nutrition, Unit of Public Health Nutrition, NOVUM, Karolinska Institutet, Hälsovägen 7, 14157 Huddinge, Stockholm, Sweden.
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Xu Y, Krause A, Hamai H, Harvey BG, Worgall TS, Worgall S. Proinflammatory phenotype and increased caveolin-1 in alveolar macrophages with silenced CFTR mRNA. PLoS One 2010; 5:e11004. [PMID: 20543983 PMCID: PMC2882373 DOI: 10.1371/journal.pone.0011004] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2010] [Accepted: 05/15/2010] [Indexed: 11/18/2022] Open
Abstract
The inflammatory milieu in the respiratory tract in cystic fibrosis (CF) has been linked to the defective expression of the cystic transmembrane regulator (CFTR) in epithelial cells. Alveolar macrophages (AM), important contibutors to inflammatory responses in the lung, also express CFTR. The present study analyzes the phenotype of human AM with silenced CFTR. Expression of CFTR mRNA and the immature form of the CFTR protein decreased 100-fold and 5.2-fold, respectively, in AM transfected with a CFTR specific siRNA (CFTR-siRNA) compared to controls. Reduction of CFTR expression in AM resulted in increased secretion of IL-8, increased phosphorylation of NF-κB, a positive regulator of IL-8 expression, and decreased expression of IκB-α, the inhibitory protein of NF-κB activation. AM with silenced CFTR expression also showed increased apoptosis. We hypothesized that caveolin-1 (Cav1), a membrane protein that is co-localized with CFTR in lipid rafts and that is related to inflammation and apoptosis in macrophages, may be affected by decreased CFTR expression. Messenger RNA and protein levels of Cav1 were increased in AM with silenced CFTR. Expression and transcriptional activity of sterol regulatory element binding protein (SREBP), a negative transcriptional regulator of Cav1, was decreased in AM with silenced CFTR, but total and free cholesterol mass did not change. These findings indicate that silencing of CFTR in human AM results in an inflammatory phenotype and apoptosis, which is associated to SREBP-mediated regulation of Cav1.
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Affiliation(s)
- Yaqin Xu
- Department of Pediatrics, Weill Cornell Medical College, New York, New York, United States of America
| | - Anja Krause
- Department of Genetic Medicine, Weill Cornell Medical College, New York, New York, United States of America
| | - Hiroko Hamai
- Department of Pathology, Columbia University, New York, New York, United States of America
| | - Ben-Gary Harvey
- Department of Genetic Medicine, Weill Cornell Medical College, New York, New York, United States of America
| | - Tilla S. Worgall
- Department of Pathology, Columbia University, New York, New York, United States of America
| | - Stefan Worgall
- Department of Pediatrics, Weill Cornell Medical College, New York, New York, United States of America
- Department of Genetic Medicine, Weill Cornell Medical College, New York, New York, United States of America
- * E-mail:
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Fang D, West RH, Manson ME, Ruddy J, Jiang D, Previs SF, Sonawane ND, Burgess JD, Kelley TJ. Increased plasma membrane cholesterol in cystic fibrosis cells correlates with CFTR genotype and depends on de novo cholesterol synthesis. Respir Res 2010; 11:61. [PMID: 20487541 PMCID: PMC2880018 DOI: 10.1186/1465-9921-11-61] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2010] [Accepted: 05/20/2010] [Indexed: 01/12/2023] Open
Abstract
Background Previous observations demonstrate that Cftr-null cells and tissues exhibit alterations in cholesterol processing including perinuclear cholesterol accumulation, increased de novo synthesis, and an increase in plasma membrane cholesterol accessibility compared to wild type controls. The hypothesis of this study is that membrane cholesterol accessibility correlates with CFTR genotype and is in part influenced by de novo cholesterol synthesis. Methods Electrochemical detection of cholesterol at the plasma membrane is achieved with capillary microelectrodes with a modified platinum coil that accepts covalent attachment of cholesterol oxidase. Modified electrodes absent cholesterol oxidase serves as a baseline control. Cholesterol synthesis is determined by deuterium incorporation into lipids over time. Incorporation into cholesterol specifically is determined by mass spectrometry analysis. All mice used in the study are on a C57Bl/6 background and are between 6 and 8 weeks of age. Results Membrane cholesterol measurements are elevated in both R117H and ΔF508 mouse nasal epithelium compared to age-matched sibling wt controls demonstrating a genotype correlation to membrane cholesterol detection. Expression of wt CFTR in CF epithelial cells reverts membrane cholesterol to WT levels further demonstrating the impact of CFTR on these processes. In wt epithelial cell, the addition of the CFTR inhibitors, Gly H101 or CFTRinh-172, for 24 h surprisingly results in an initial drop in membrane cholesterol measurement followed by a rebound at 72 h suggesting a feedback mechanism may be driving the increase in membrane cholesterol. De novo cholesterol synthesis contributes to membrane cholesterol accessibility. Conclusions The data in this study suggest that CFTR influences cholesterol trafficking to the plasma membrane, which when depleted, leads to an increase in de novo cholesterol synthesis to restore membrane content.
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Affiliation(s)
- Danjun Fang
- Department of Pediatrics and Pharmacology, Case Western Reserve University, Cleveland, OH 44106, USA
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42
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Guo Y, Su M, Su M, McNutt MA, Gu J. Expression and distribution of cystic fibrosis transmembrane conductance regulator in neurons of the spinal cord. J Neurosci Res 2010; 87:3611-9. [PMID: 19533735 PMCID: PMC7167064 DOI: 10.1002/jnr.22154] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
To verify the hypothesis that cystic fibrosis transmembrane conductance regulator (CFTR) is expressed in neurons of the human spinal cord, we investigated the presence and distribution of CFTR protein and mRNA in different segments of the human spinal cord obtained from autopsies. The techniques employed included reverse transcriptase‐polymerase chain reaction (RT‐PCR) to detect CFTR gene expression, in situ hybridization to detect mRNA distribution, and immunohistochemistry to detect protein distribution. The specificity of these experiments was established with extensive controls. We found widespread and abundant expression of CFTR in neurons of the human spinal cord. CFTR protein and mRNA are localized to the cytoplasm of neurons in all segments of the spinal cord but not to glial fibrillary acidic protein (GFAP)‐positive cells. CFTR is a very important molecule, acting as a chloride channel and regulating many physiological functions, including salt transport, fluid flow, and intracellular ion concentrations. Its mutation causes cystic fibrosis. Our finding of abundant CFTR in the spinal cord suggests that this molecule may be significant in the normal function and pathology of the spinal cord. © 2009 Wiley‐Liss, Inc.
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Affiliation(s)
- Yong Guo
- Department of Pathology, Peking University Health Science Center, Beijing, China
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Cholon DM, O'Neal WK, Randell SH, Riordan JR, Gentzsch M. Modulation of endocytic trafficking and apical stability of CFTR in primary human airway epithelial cultures. Am J Physiol Lung Cell Mol Physiol 2009; 298:L304-14. [PMID: 20008117 DOI: 10.1152/ajplung.00016.2009] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
CFTR is a highly regulated apical chloride channel of epithelial cells that is mutated in cystic fibrosis (CF). In this study, we characterized the apical stability and intracellular trafficking of wild-type and mutant CFTR in its native environment, i.e., highly differentiated primary human airway epithelial (HAE) cultures. We labeled the apical pool of CFTR and subsequently visualized the protein in intracellular compartments. CFTR moved from the apical surface to endosomes and then efficiently recycled back to the surface. CFTR endocytosis occurred more slowly in polarized than in nonpolarized HAE cells or in a polarized epithelial cell line. The most common mutation in CF, DeltaF508 CFTR, was rescued from endoplasmic reticulum retention by low-temperature incubation but transited from the apical membrane to endocytic compartments more rapidly and recycled less efficiently than wild-type CFTR. Incubation with small-molecule correctors resulted in DeltaF508 CFTR at the apical membrane but did not restore apical stability. To stabilize the mutant protein at the apical membrane, we found that the dynamin inhibitor Dynasore and the cholesterol-extracting agent cyclodextrin dramatically reduced internalization of DeltaF508, whereas the proteasomal inhibitor MG-132 completely blocked endocytosis of DeltaF508. On examination of intrinsic properties of CFTR that may affect its apical stability, we found that N-linked oligosaccharides were not necessary for transport to the apical membrane but were required for efficient apical recycling and, therefore, influenced the turnover of surface CFTR. Thus apical stability of CFTR in its native environment is affected by properties of the protein and modulation of endocytic trafficking.
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Affiliation(s)
- Deborah M Cholon
- Cystic Fibrosis Research Center and Department of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-7248, USA
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44
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Mailhot G, Ravid Z, Barchi S, Moreau A, Rabasa-Lhoret R, Levy E. CFTR knockdown stimulates lipid synthesis and transport in intestinal Caco-2/15 cells. Am J Physiol Gastrointest Liver Physiol 2009; 297:G1239-49. [PMID: 19808659 DOI: 10.1152/ajpgi.00206.2009] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Cystic fibrosis transmembrane conductance regulator (CFTR) is a chloride channel highly expressed in epithelial cells of the gastrointestinal tract. Mutations in the CFTR gene cause cystic fibrosis (CF), a disease characterized by pancreatic insufficiency, fat malabsorption, and steatorrhea. Despite the administration of pancreatic enzymes to normalize malabsorption, CF patients still experienced lipid fecal loss, nutritional deficiencies, and abnormalities in serum lipid profile, suggesting the presence of intrinsic defects in the intestinal handling of nutrients. The objective of the present study was to assess the impact of CFTR gene knockdown on intracellular lipid metabolism of the intestinal Caco-2/15 cell line. Partial CFTR gene inactivation led to cellular lipid accretion of phospholipids, triglycerides, and cholesteryl esters. Likewise, secretion of these lipid fractions was significantly increased following CFTR gene manipulation. As expected from these findings, the output of triglyceride-rich lipoproteins showed the same increasing pattern. Investigation of the mechanisms underlying these changes revealed that CFTR knockdown resulted in raised levels of apolipoproteins in cells and media and microsomal transfer protein activity, two important factors for the efficient assembly and secretion of lipoproteins. Similarly, scrutiny of the enzymatic monoacylglycerol acyltransferase and diacylglycerol acyltransferase, which exhibit dynamic function in triacylglycerol resynthesis and chylomicron formation in enterocytes, revealed a significant augmentation in their activity. Conversely, cholesterol uptake mediated by Niemann-Pick C1 like 1, Scavenger Receptor Class B Type I, and ATP-binding cassette G8 remains unaffected by genetic modification of CFTR. Collectively, these results highlight the role played by CFTR in intestinal handling of lipids and may suggest that factors other than defective CFTR are responsible for the abnormal intracellular events leading to fat malabsorption in CF patients.
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Affiliation(s)
- Geneviève Mailhot
- Research Centre, CHU Sainte-Justine, Université de Montréal, Québec, Canada
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Guo Y, Su M, McNutt MA, Gu J. Expression and distribution of cystic fibrosis transmembrane conductance regulator in neurons of the human brain. J Histochem Cytochem 2009; 57:1113-20. [PMID: 19654104 DOI: 10.1369/jhc.2009.953455] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The importance of the molecule cystic fibrosis transmembrane conductance regulator (CFTR) is reflected in the many physiological functions it regulates. It is known to be present in epithelial cells of the lungs, pancreas, sweat glands, gut, and other tissues, and gene mutations of CFTR cause cystic fibrosis (CF). We studied the expression and distribution of CFTR in the human brain with reverse transcriptase polymerase chain reaction, in situ hybridization, and immunohistochemistry. This study demonstrates widespread and abundant expression of CFTR in neurons of the human brain. Techniques of double labeling and evaluation of consecutive tissue sections localized CFTR protein and mRNA signals to the cytoplasm of neurons in all regions of the brain studied, but not to glial cells. The presence of CFTR in central neurons not only provides a possible explanation for the neural symptoms observed in CF patients, but also may lead to a better understanding of the functions of CFTR in the human brain.
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Affiliation(s)
- Yong Guo
- Department of Pathology, School of Basic Medical Sciences, Peking (Beijing) University Health Science Center, Beijing, China
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Park HJ, Mylvaganum M, McPherson A, Fewell SW, Brodsky JL, Lingwood CA. A soluble sulfogalactosyl ceramide mimic promotes Delta F508 CFTR escape from endoplasmic reticulum associated degradation. ACTA ACUST UNITED AC 2009; 16:461-70. [PMID: 19389632 DOI: 10.1016/j.chembiol.2009.02.014] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2008] [Revised: 02/19/2009] [Accepted: 02/25/2009] [Indexed: 10/20/2022]
Abstract
AdaSGC binds Hsc70s to inhibit ATPase activity. Using single-turnover assays, adaSGC, a soluble SGC mimic, preferentially inhibited Hsp40-activated Hsc70 ATP hydrolysis (Ki approximately 10 microM) to reduce C-terminal Hsc70-peptide binding and, potentially, chaperone function. ERAD of misfolded Delta F508 CFTR requires Hsc70-Hsp40 chaperones. In transfected baby hamster kidney (BHK) cells, adaSGC increased Delta F508CFTR ERAD escape, and after low-temperature glycerol rescue, maturation, and iodide efflux. Inhibition of SGC biosynthesis reduced Delta F508CFTR but not wtCFTR expression, whereas depletion of other glycosphingolipids had no affect. WtCFTR transfected BHK cells showed increased SGC synthesis compared with Delta F508CFTR/mock-transfected cells. Partial rescue of Delta F508CFTR by low-temperature glycerol increased SGC synthesis. AdaSGC also increased cellular endogenous SGC levels. SGC in the lung, liver, and kidney was severely depleted in Delta F508CFTR compared with wtCFTR mice, suggesting a role for CFTR in SGC biosynthesis.
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Affiliation(s)
- Hyun-Joo Park
- Research Institute, Division of Molecular Structure and Function, The Hospital for Sick Children, Toronto, ON M5G 1X8, Canada
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Barriere H, Bagdany M, Bossard F, Okiyoneda T, Wojewodka G, Gruenert D, Radzioch D, Lukacs GL. Revisiting the role of cystic fibrosis transmembrane conductance regulator and counterion permeability in the pH regulation of endocytic organelles. Mol Biol Cell 2009; 20:3125-41. [PMID: 19420138 DOI: 10.1091/mbc.e09-01-0061] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Organellar acidification by the electrogenic vacuolar proton-ATPase is coupled to anion uptake and cation efflux to preserve electroneutrality. The defective organellar pH regulation, caused by impaired counterion conductance of the mutant cystic fibrosis transmembrane conductance regulator (CFTR), remains highly controversial in epithelia and macrophages. Restricting the pH-sensitive probe to CFTR-containing vesicles, the counterion and proton permeability, and the luminal pH of endosomes were measured in various cells, including genetically matched CF and non-CF human respiratory epithelia, as well as cftr(+/+) and cftr(-/-) mouse alveolar macrophages. Passive proton and relative counterion permeabilities, determinants of endosomal, lysosomal, and phagosomal pH-regulation, were probed with FITC-conjugated transferrin, dextran, and Pseudomonas aeruginosa, respectively. Although CFTR function could be documented in recycling endosomes and immature phagosomes, neither channel activation nor inhibition influenced the pH in any of these organelles. CFTR heterologous overexpression also failed to alter endocytic organellar pH. We propose that the relatively large CFTR-independent counterion and small passive proton permeability ensure efficient shunting of the proton-ATPase-generated membrane potential. These results have implications in the regulation of organelle acidification in general and demonstrate that perturbations of the endolysosomal organelles pH homeostasis cannot be linked to the etiology of the CF lung disease.
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Affiliation(s)
- Herve Barriere
- Department of Physiology, McGill University, Montreal, Quebec, H3G 1Y6, Canada
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Xu Y, Tertilt C, Krause A, Quadri LEN, Crystal RG, Worgall S. Influence of the cystic fibrosis transmembrane conductance regulator on expression of lipid metabolism-related genes in dendritic cells. Respir Res 2009; 10:26. [PMID: 19344509 PMCID: PMC2683168 DOI: 10.1186/1465-9921-10-26] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2008] [Accepted: 04/03/2009] [Indexed: 12/23/2022] Open
Abstract
Background Cystic fibrosis (CF) is caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. Infections of the respiratory tract are a hallmark in CF. The host immune responses in CF are not adequate to eradicate pathogens, such as P. aeruginosa. Dendritic cells (DC) are crucial in initiation and regulation of immune responses. Changes in DC function could contribute to abnormal immune responses on multiple levels. The role of DC in CF lung disease remains unknown. Methods This study investigated the expression of CFTR gene in bone marrow-derived DC. We compared the differentiation and maturation profile of DC from CF and wild type (WT) mice. We analyzed the gene expression levels in DC from naive CF and WT mice or following P. aeruginosa infection. Results CFTR is expressed in DC with lower level compared to lung tissue. DC from CF mice showed a delayed in the early phase of differentiation. Gene expression analysis in DC generated from naive CF and WT mice revealed decreased expression of Caveolin-1 (Cav1), a membrane lipid raft protein, in the CF DC compared to WT DC. Consistently, protein and activity levels of the sterol regulatory element binding protein (SREBP), a negative regulator of Cav1 expression, were increased in CF DC. Following exposure to P. aeruginosa, expression of 3β-hydroxysterol-Δ7 reductase (Dhcr7) and stearoyl-CoA desaturase 2 (Scd2), two enzymes involved in the lipid metabolism that are also regulated by SREBP, was less decreased in the CF DC compared to WT DC. Conclusion These results suggest that CFTR dysfunction in DC affects factors involved in membrane structure and lipid-metabolism, which may contribute to the abnormal inflammatory and immune response characteristic of CF.
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Affiliation(s)
- Yaqin Xu
- Department of Pediatrics, Weill Cornell Medical College, New York, USA.
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Bradford EM, Sartor MA, Gawenis LR, Clarke LL, Shull GE. Reduced NHE3-mediated Na+ absorption increases survival and decreases the incidence of intestinal obstructions in cystic fibrosis mice. Am J Physiol Gastrointest Liver Physiol 2009; 296:G886-98. [PMID: 19164484 PMCID: PMC2670667 DOI: 10.1152/ajpgi.90520.2008] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
In cystic fibrosis, impaired secretion resulting from loss of activity of the cystic fibrosis transmembrane conductance regulator (CFTR) causes dehydration of intestinal contents and life-threatening obstructions. Conversely, impaired absorption resulting from loss of the NHE3 Na+/H+ exchanger causes increased fluidity of the intestinal contents and diarrhea. To test the hypothesis that reduced NHE3-mediated absorption could increase survival and prevent some of the intestinal pathologies of cystic fibrosis, Cftr/Nhe3 double heterozygous mice were mated and their offspring analyzed. Cftr-null mice lacking one or both copies of the NHE3 gene exhibited increased fluidity of their intestinal contents, which prevented the formation of obstructions and increased survival. Goblet cell hyperplasia was eliminated, but not the accumulation of Paneth cell granules or increased cell proliferation in the crypts. Microarray analysis of small intestine RNA from Cftr-null, NHE3-null, and double-null mice all revealed downregulation of genes involved in xenobiotic metabolism, including a cohort of genes involved in glutathione metabolism. Expression of energy metabolism genes was altered, but there were no changes in genes involved in inflammation. Total intracellular glutathione was increased in the jejunum of all of the mutants and the ratio of reduced to oxidized glutathione was reduced in Cftr-null mutants, indicating that CFTR deficiency affects intestinal glutathione metabolism. The data establish a major role for NHE3 in regulating the fluidity of the intestinal contents and show that reduced NHE3-mediated absorption reverses some of the intestinal pathologies of cystic fibrosis, thus suggesting that it may serve as a potential therapeutic target.
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Affiliation(s)
- Emily M. Bradford
- Department of Molecular Genetics, Biochemistry and Microbiology and Department of Environmental Health, University of Cincinnati College of Medicine, Cincinnati, Ohio; Department of Physiology, University of Utah, Salt Lake City, Utah; and Dalton Cardiovascular Research Center and the Department of Biomedical Sciences, University of Missouri, Columbia, Missouri
| | - Maureen A. Sartor
- Department of Molecular Genetics, Biochemistry and Microbiology and Department of Environmental Health, University of Cincinnati College of Medicine, Cincinnati, Ohio; Department of Physiology, University of Utah, Salt Lake City, Utah; and Dalton Cardiovascular Research Center and the Department of Biomedical Sciences, University of Missouri, Columbia, Missouri
| | - Lara R. Gawenis
- Department of Molecular Genetics, Biochemistry and Microbiology and Department of Environmental Health, University of Cincinnati College of Medicine, Cincinnati, Ohio; Department of Physiology, University of Utah, Salt Lake City, Utah; and Dalton Cardiovascular Research Center and the Department of Biomedical Sciences, University of Missouri, Columbia, Missouri
| | - Lane L. Clarke
- Department of Molecular Genetics, Biochemistry and Microbiology and Department of Environmental Health, University of Cincinnati College of Medicine, Cincinnati, Ohio; Department of Physiology, University of Utah, Salt Lake City, Utah; and Dalton Cardiovascular Research Center and the Department of Biomedical Sciences, University of Missouri, Columbia, Missouri
| | - Gary E. Shull
- Department of Molecular Genetics, Biochemistry and Microbiology and Department of Environmental Health, University of Cincinnati College of Medicine, Cincinnati, Ohio; Department of Physiology, University of Utah, Salt Lake City, Utah; and Dalton Cardiovascular Research Center and the Department of Biomedical Sciences, University of Missouri, Columbia, Missouri
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Abstract
PURPOSE OF REVIEW Expression of defective cystic fibrosis transmembrane conductance regulator (CFTR), the cause for cystic fibrosis, affects fatty acid, cholesterol and sphingolipid metabolism. This review summarizes recent observations and evaluates current understanding of mechanisms. RECENT FINDINGS Recent observations implicate CFTR, in addition to known effects on fatty acid and cholesterol metabolism, in the regulation of sphingolipid metabolism and suggest that this pathway is relevant to inflammation and infection. A common mechanism on how CFTR affects such a wide spectrum of lipid classes is currently not known. One mechanism for low linoleic acid, amenable to inhibition by docosahexaenoic acid, is increased metabolism in the n-6 fatty acid pathway. Accumulation of free cholesterol in distinct perinuclear compartments, reversible by overexpression of rab9, suggests that cystic fibrosis and the lysosomal storage disease Niemann-Pick-C could share similar cell signaling defects, in addition to increased cAMP signaling and sterol-regulatory element binding protein (SREBP) expression that affect cholesterol metabolism. Novel is the recognition that CFTR modulates ceramide mass and uptake of sphingosine-1- phosphate. Experiments in different cystic fibrosis-mouse models, although not able to establish whether ceramide mass is increased or decreased, suggest that normalization of ceramide decreases infection and selected parameters of inflammation, of relevance to the complex phenotype that characterizes cystic fibrosis. SUMMARY Expression of defective CFTR has profound effects on fatty acid, cholesterol and sphingolipid metabolism, for which mechanisms are currently poorly understood. Recent studies in different cystic fibrosis models suggest a causal relationship between altered ceramide mass and increased inflammation and susceptibility to infection. Studies in cystic fibrosis knockout mouse models suggest that normalization of ceramide decreases infection and inflammation. Studies that evaluate the diagnostic and clinical relevance of sphingolipids in patients with cystic fibrosis are needed.
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Affiliation(s)
- Tilla S Worgall
- Department of Pathology, Pediatrics and Institute of Human Nutrition, Columbia University, BB 457, New York 10032, USA.
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