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Maus M, López-Polo V, Mateo L, Lafarga M, Aguilera M, De Lama E, Meyer K, Sola A, Lopez-Martinez C, López-Alonso I, Guasch-Piqueras M, Hernandez-Gonzalez F, Chaib S, Rovira M, Sanchez M, Faner R, Agusti A, Diéguez-Hurtado R, Ortega S, Manonelles A, Engelhardt S, Monteiro F, Stephan-Otto Attolini C, Prats N, Albaiceta G, Cruzado JM, Serrano M. Iron accumulation drives fibrosis, senescence and the senescence-associated secretory phenotype. Nat Metab 2023; 5:2111-2130. [PMID: 38097808 PMCID: PMC10730403 DOI: 10.1038/s42255-023-00928-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Accepted: 10/11/2023] [Indexed: 12/21/2023]
Abstract
Fibrogenesis is part of a normal protective response to tissue injury that can become irreversible and progressive, leading to fatal diseases. Senescent cells are a main driver of fibrotic diseases through their secretome, known as senescence-associated secretory phenotype (SASP). Here, we report that cellular senescence, and multiple types of fibrotic diseases in mice and humans are characterized by the accumulation of iron. We show that vascular and hemolytic injuries are efficient in triggering iron accumulation, which in turn can cause senescence and promote fibrosis. Notably, we find that senescent cells persistently accumulate iron, even when the surge of extracellular iron has subdued. Indeed, under normal conditions of extracellular iron, cells exposed to different types of senescence-inducing insults accumulate abundant ferritin-bound iron, mostly within lysosomes, and present high levels of labile iron, which fuels the generation of reactive oxygen species and the SASP. Finally, we demonstrate that detection of iron by magnetic resonance imaging might allow non-invasive assessment of fibrotic burden in the kidneys of mice and in patients with renal fibrosis. Our findings suggest that iron accumulation plays a central role in senescence and fibrosis, even when the initiating events may be independent of iron, and identify iron metabolism as a potential therapeutic target for senescence-associated diseases.
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Grants
- SAF2017-82613-R "la Caixa" Foundation (Caixa Foundation)
- of M. Serrano was funded by the IRB and “laCaixa” Foundation, and by grants from the Spanish Ministry of Science co-funded by the European Regional Development Fund (ERDF) (SAF2017-82613-R), European Research Council (ERC-2014-AdG/669622), and grant RETOS COLABORACION RTC2019-007125-1 from MCIN/AEI, and Secretaria d'Universitats i Recerca del Departament d'Empresa i Coneixement of Catalonia (Grup de Recerca consolidat 2017 SGR 282)
- M.M. received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement (No 794744) and from the Spanish Ministry of Science and Innovation (MCIN) (RYC2020-030652-I /AEI /10.13039/501100011033)
- V.L.P. was recipient of a predoctoral contract from Spanish Ministry of Education (FPU-18/05917).
- K.M. was recipient of fellowships from the German Cardiac, the German Research Foundation, and a postdoctoral contract Juan de la Cierva from the MCIN.
- F.H.G. was supported by the PhD4MD Collaborative Research Training Programme for Medical Doctors (IRB Barcelona/Hospital Clinic/IDIBAPS).
- M. Sanchez was funded by grants PID2021-122436OB-I00 from MCIN/ AEI /10.13039/501100011033 / FEDER, UE, and RETOS COLABORACION RTC2019-007074-1 from MCIN/AEI /10.13039/501100011033.
- G.A. was funded by Instituto de Salud Carlos III through project PI 20/01360, FEDER funds.
- J.M.C was funded by Instituto de Salud Carlos III through projects PI18/00910 and PI21/00931 (Co-funded by European Regional Development Fund. ERDF, a way to build Europe), and thanks CERCA Programme / Generalitat de Catalunya for institutional support.
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Affiliation(s)
- Mate Maus
- Institute for Research in Biomedicine (IRB Barcelona), Barcelona Institute of Science and Technology (BIST), Barcelona, Spain.
- Vall d'Hebron Institute of Oncology, Barcelona, Spain.
| | - Vanessa López-Polo
- Institute for Research in Biomedicine (IRB Barcelona), Barcelona Institute of Science and Technology (BIST), Barcelona, Spain
| | - Lidia Mateo
- Institute for Research in Biomedicine (IRB Barcelona), Barcelona Institute of Science and Technology (BIST), Barcelona, Spain
| | - Miguel Lafarga
- Departamento de Anatomía y Biología Celular, Universidad de Cantabria-IDIVAL, Santander, Spain
| | - Mònica Aguilera
- Institute for Research in Biomedicine (IRB Barcelona), Barcelona Institute of Science and Technology (BIST), Barcelona, Spain
| | - Eugenia De Lama
- Radiology Department, Hospital Universitari de Bellvitge, IDIBELL, L'Hospitalet de Llobregat, Barcelona, Spain
| | - Kathleen Meyer
- Institute for Research in Biomedicine (IRB Barcelona), Barcelona Institute of Science and Technology (BIST), Barcelona, Spain
- Altos Labs, Cambridge Institute of Science, Cambridge, UK
| | - Anna Sola
- Nephrology and Renal Transplantation Research Group. Bellvitge Biomedical Research Institute (IDIBELL), Hospitalet de Llobregat, Barcelona, Spain
| | - Cecilia Lopez-Martinez
- Departamento de Biología Funcional, Instituto Universitario de Oncología del principado de Asturias, Universidad de Oviedo, Oviedo, Spain
- Unidad de Cuidados Intensivos Cardiológicos. Hospital Universitario Central de Asturias, Instituto de Investigación Sanitaria del Principado de Asturias, Oviedo, Spain
- CIBER-Enfermedades Respiratorias, Instituto de Salud Carlos III, Madrid, Spain
| | - Ines López-Alonso
- Departamento de Morfología y Biología Celular, Universidad de Oviedo, Instituto de Investigación Sanitaria del Principado de Asturias, Oviedo, Spain
| | | | - Fernanda Hernandez-Gonzalez
- Institute for Research in Biomedicine (IRB Barcelona), Barcelona Institute of Science and Technology (BIST), Barcelona, Spain
- Department of Pulmonary Medicine, Respiratory Institute, Hospital Clinic, IDIBAPS, University of Barcelona, Barcelona, Spain
| | - Selim Chaib
- Institute for Research in Biomedicine (IRB Barcelona), Barcelona Institute of Science and Technology (BIST), Barcelona, Spain
| | - Miguel Rovira
- Institute for Research in Biomedicine (IRB Barcelona), Barcelona Institute of Science and Technology (BIST), Barcelona, Spain
| | - Mayka Sanchez
- Iron Metabolism: Regulation and Diseases Group, Department of Basic Sciences, Universitat Internacional de Catalunya (UIC), Sant Cugat del Vallès, Spain
| | - Rosa Faner
- Biomedicine Department, University of Barcelona, IDIBAPS, CIBERES, Barcelona, Spain
| | - Alvar Agusti
- Universitat de Barcelona, Institut Respiratori, Hospital Clinic, IDIBAPS, CIBERES, Barcelona, Spain
| | - Rodrigo Diéguez-Hurtado
- Deparment of Tissue Morphogenesis, Max Planck Institute for Molecular Biomedicine, Münster, Germany
| | - Sagrario Ortega
- Transgenics Unit, Spanish National Cancer Research Centre (CNIO), Madrid, Spain
| | - Anna Manonelles
- Nephrology and Renal Transplantation Research Group. Bellvitge Biomedical Research Institute (IDIBELL), Hospitalet de Llobregat, Barcelona, Spain
- Nephrology Department, Bellvitge University Hospital, Hospitalet de Llobregat, Barcelona, Spain
- Department of Clinical Sciences, University of Barcelona, Hospitalet de Llobregat, Barcelona, Spain
| | - Stefan Engelhardt
- Institute of Pharmacology and Toxicology, Technical University of Munich (TUM), Munich, Germany
- DZHK (German Centre for Cardiovascular Research), Partner Site Munich Heart Alliance, Munich, Germany
| | - Freddy Monteiro
- Institute for Research in Biomedicine (IRB Barcelona), Barcelona Institute of Science and Technology (BIST), Barcelona, Spain
| | - Camille Stephan-Otto Attolini
- Institute for Research in Biomedicine (IRB Barcelona), Barcelona Institute of Science and Technology (BIST), Barcelona, Spain
| | - Neus Prats
- Institute for Research in Biomedicine (IRB Barcelona), Barcelona Institute of Science and Technology (BIST), Barcelona, Spain
| | - Guillermo Albaiceta
- Departamento de Biología Funcional, Instituto Universitario de Oncología del principado de Asturias, Universidad de Oviedo, Oviedo, Spain
- Unidad de Cuidados Intensivos Cardiológicos. Hospital Universitario Central de Asturias, Instituto de Investigación Sanitaria del Principado de Asturias, Oviedo, Spain
- CIBER-Enfermedades Respiratorias, Instituto de Salud Carlos III, Madrid, Spain
| | - Josep M Cruzado
- Nephrology and Renal Transplantation Research Group. Bellvitge Biomedical Research Institute (IDIBELL), Hospitalet de Llobregat, Barcelona, Spain
- Nephrology Department, Bellvitge University Hospital, Hospitalet de Llobregat, Barcelona, Spain
- Department of Clinical Sciences, University of Barcelona, Hospitalet de Llobregat, Barcelona, Spain
| | - Manuel Serrano
- Institute for Research in Biomedicine (IRB Barcelona), Barcelona Institute of Science and Technology (BIST), Barcelona, Spain.
- Altos Labs, Cambridge Institute of Science, Cambridge, UK.
- Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Spain.
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2
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Wang C, Hua S, Song L. Ferroptosis in pulmonary fibrosis: an emerging therapeutic target. Front Physiol 2023; 14:1205771. [PMID: 37664432 PMCID: PMC10470006 DOI: 10.3389/fphys.2023.1205771] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Accepted: 07/28/2023] [Indexed: 09/05/2023] Open
Abstract
In recent years, the role of ferroptosis in pulmonary fibrosis has garnered increasing interest as a potential therapeutic target. Pulmonary fibrosis is a pathological process characterized by the accumulation of extracellular matrix in affected lung tissues, and currently, there are no effective therapies for preventing or reversing the fibrotic lesions. Ferroptosis is a form of programmed cell death that is regulated by a network of enzymes and signaling pathways. Dysregulation of ferroptosis has been implicated in several diseases, including pulmonary fibrosis. The accumulation of lipid peroxides in the course of ferroptosis causes damage to cell membranes and other cellular components, leading ultimately to cell death. Relevant targets for therapeutic intervention in ferroptosis include key enzymes, such as glutathione peroxidase 4, transcription factors like nuclear factor erythroid 2-related factor 2, and iron chelation. This review provides an overview of the emerging role of ferroptosis in pulmonary fibrosis and highlights potential therapeutic targets in this pathway. Further research is needed to develop safe and effective approaches targeting ferroptosis in treatment of pulmonary fibrosis.
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Affiliation(s)
- Chunyan Wang
- Department of General Practice, Key Laboratory of Organ Regeneration and Transplantation of the Ministry of Education, The First Hospital of Jilin University, Changchun, China
| | - Shucheng Hua
- Department of Respiratory Medicine, Center for Pathogen Biology and Infectious Diseases, The First Hospital of Jilin University, Changchun, China
| | - Lei Song
- Department of Respiratory Medicine, Center for Pathogen Biology and Infectious Diseases, The First Hospital of Jilin University, Changchun, China
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Carroll OR, Pillar AL, Brown AC, Feng M, Chen H, Donovan C. Advances in respiratory physiology in mouse models of experimental asthma. Front Physiol 2023; 14:1099719. [PMID: 37008013 PMCID: PMC10060990 DOI: 10.3389/fphys.2023.1099719] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Accepted: 02/07/2023] [Indexed: 03/18/2023] Open
Abstract
Recent advances in mouse models of experimental asthma coupled with vast improvements in systems that assess respiratory physiology have considerably increased the accuracy and human relevance of the outputs from these studies. In fact, these models have become important pre-clinical testing platforms with proven value and their capacity to be rapidly adapted to interrogate emerging clinical concepts, including the recent discovery of different asthma phenotypes and endotypes, has accelerated the discovery of disease-causing mechanisms and increased our understanding of asthma pathogenesis and the associated effects on lung physiology. In this review, we discuss key distinctions in respiratory physiology between asthma and severe asthma, including the magnitude of airway hyperresponsiveness and recently discovered disease drivers that underpin this phenomenon such as structural changes, airway remodeling, airway smooth muscle hypertrophy, altered airway smooth muscle calcium signaling, and inflammation. We also explore state-of-the-art mouse lung function measurement techniques that accurately recapitulate the human scenario as well as recent advances in precision cut lung slices and cell culture systems. Furthermore, we consider how these techniques have been applied to recently developed mouse models of asthma, severe asthma, and asthma-chronic obstructive pulmonary disease overlap, to examine the effects of clinically relevant exposures (including ovalbumin, house dust mite antigen in the absence or presence of cigarette smoke, cockroach allergen, pollen, and respiratory microbes) and to increase our understanding of lung physiology in these diseases and identify new therapeutic targets. Lastly, we focus on recent studies that examine the effects of diet on asthma outcomes, including high fat diet and asthma, low iron diet during pregnancy and predisposition to asthma development in offspring, and environmental exposures on asthma outcomes. We conclude our review with a discussion of new clinical concepts in asthma and severe asthma that warrant investigation and how we could utilize mouse models and advanced lung physiology measurement systems to identify factors and mechanisms with potential for therapeutic targeting.
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Affiliation(s)
- Olivia R. Carroll
- Hunter Medical Research Institute, The University of Newcastle, Newcastle, NSW, Australia
| | - Amber L. Pillar
- Hunter Medical Research Institute, The University of Newcastle, Newcastle, NSW, Australia
| | - Alexandra C. Brown
- Hunter Medical Research Institute, The University of Newcastle, Newcastle, NSW, Australia
| | - Min Feng
- Faculty of Science, School of Life Sciences, University of Technology Sydney, Sydney, NSW, Australia
| | - Hui Chen
- Faculty of Science, School of Life Sciences, University of Technology Sydney, Sydney, NSW, Australia
| | - Chantal Donovan
- Hunter Medical Research Institute, The University of Newcastle, Newcastle, NSW, Australia
- Faculty of Science, School of Life Sciences, University of Technology Sydney, Sydney, NSW, Australia
- *Correspondence: Chantal Donovan,
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Abstract
Cystic fibrosis (CF) pathophysiology is hallmarked by excessive inflammation and the inability to resolve lung infections, contributing to morbidity and eventually mortality. Paradoxically, despite a robust inflammatory response, CF lungs fail to clear bacteria and are susceptible to chronic infections. Impaired mucociliary transport plays a critical role in chronic infection but the immune mechanisms contributing to the adaptation of bacteria to the lung microenvironment is not clear. CFTR modulator therapy has advanced CF life expectancy opening up the need to understand changes in immunity as CF patients age. Here, we have summarized the current understanding of immune dysregulation in CF.
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Affiliation(s)
- Emanuela M Bruscia
- Department of Pediatrics, Section of Pulmonology, Allergy, Immunology and Sleep Medicine, Yale University School of Medicine, New Haven, CT, USA.
| | - Tracey L Bonfield
- Department of Genetics and Genome Sciences, Case Western Reserve University School of Medicine, Cleveland, OH, USA.
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5
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Donegan RK. The role of host heme in bacterial infection. Biol Chem 2022; 403:1017-1029. [PMID: 36228088 DOI: 10.1515/hsz-2022-0192] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2022] [Accepted: 09/14/2022] [Indexed: 11/15/2022]
Abstract
Heme is an indispensable cofactor for almost all aerobic life, including the human host and many bacterial pathogens. During infection, heme and hemoproteins are the largest source of bioavailable iron, and pathogens have evolved various heme acquisition pathways to satisfy their need for iron and heme. Many of these pathways are regulated transcriptionally by intracellular iron levels, however, host heme availability and intracellular heme levels have also been found to regulate heme uptake in some species. Knowledge of these pathways has helped to uncover not only how these bacteria incorporate host heme into their metabolism but also provided insight into the importance of host heme as a nutrient source during infection. Within this review is covered multiple aspects of the role of heme at the host pathogen interface, including the various routes of heme biosynthesis, how heme is sequestered by the host, and how heme is scavenged by bacterial pathogens. Also discussed is how heme and hemoproteins alter the behavior of the host immune system and bacterial pathogens. Finally, some unanswered questions about the regulation of heme uptake and how host heme is integrated into bacterial metabolism are highlighted.
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Affiliation(s)
- Rebecca K Donegan
- Department of Chemistry, Barnard College, 3009 Broadway, New York, NY, 10027, USA
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6
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Physiological Effects of Ferroptosis on Organ Fibrosis. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2022; 2022:5295434. [PMID: 36238649 PMCID: PMC9553398 DOI: 10.1155/2022/5295434] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Revised: 09/12/2022] [Accepted: 09/14/2022] [Indexed: 12/16/2022]
Abstract
Ferroptosis is a new type of programmed cell death with unique morphological, biochemical, and genetic features. From the initial study of histomorphology to the exploration of subcellular organelles and even molecular mechanisms, a net connecting ferroptosis and fibrosis is being woven and formed. Inflammation may be the bridge between both processes. In this review, we will discuss the ferroptosis theory and process and the physiological functions of ferroptosis, followed by a description of the pathological effects and the underlying mechanisms of ferroptosis in the pathogenesis of tumorigenesis, ischemic damage, degenerative lesions, autoimmune diseases, and necroinflammation. We then focus on the role of ferroptosis in the fibrosis process in the liver, lung, kidney, heart, and other organs. Although the molecular mechanism of ferroptosis has been explored extensively in the past few years, many challenges remain to be resolved to translate this information into antifibrotic practice, which is becoming a promising new direction in the field of fibrotic disease prevention and treatment.
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7
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Markovetz MR, Garbarine IC, Morrison CB, Kissner WJ, Seim I, Forest MG, Papanikolas MJ, Freeman R, Ceppe A, Ghio A, Alexis NE, Stick SM, Ehre C, Boucher RC, Esther CR, Muhlebach MS, Hill DB. Mucus and mucus flake composition and abundance reflect inflammatory and infection status in cystic fibrosis. J Cyst Fibros 2022; 21:959-966. [DOI: 10.1016/j.jcf.2022.04.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Revised: 03/11/2022] [Accepted: 04/06/2022] [Indexed: 10/18/2022]
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8
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Maniam P, Essilfie AT, Kalimutho M, Ling D, Frazer DM, Phipps S, Anderson GJ, Reid DW. Increased susceptibility of cystic fibrosis airway epithelial cells to ferroptosis. Biol Res 2021; 54:38. [PMID: 34903297 PMCID: PMC8670191 DOI: 10.1186/s40659-021-00361-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Accepted: 11/28/2021] [Indexed: 01/22/2023] Open
Abstract
BACKGROUND Defective chloride transport in airway epithelial cells (AECs) and the associated lung disease are the main causes of morbidity and early mortality in cystic fibrosis (CF). Abnormal airway iron homeostasis and the presence of lipid peroxidation products, indicative of oxidative stress, are features of CF lung disease. RESULTS Here, we report that CF AECs (IB3-1) are susceptible to ferroptosis, a type of cell death associated with iron accumulation and lipid peroxidation. Compared to isogenic CFTR corrected cells (C38), the IB3-1 cells showed increased susceptibility to cell death upon exposure to iron in the form of ferric ammonium citrate (FAC) and the ferroptosis inducer, erastin. This phenotype was accompanied by accumulation of intracellular ferrous iron and lipid peroxides and the extracellular release of malondialdehyde, all indicative of redox stress, and increased levels of lactate dehydrogenase in the culture supernatant, indicating enhanced cell injury. The ferric iron chelator deferoxamine (DFO) and the lipophilic antioxidant ferrostatin-1 inhibited FAC and erastin induced ferroptosis in IB3-1 cells. Glutathione peroxidase 4 (GPX4) expression was decreased in IB3-1 cells treated with FAC and erastin, but was unchanged in C38 AECs. Necroptosis appeared to be involved in the enhanced susceptibility of IB3-1 AECs to ferroptosis, as evidenced by partial cell death rescue with necroptosis inhibitors and enhanced mixed lineage kinase domain-like (MLKL) localisation to the plasma membrane. CONCLUSION These studies suggest that the increased susceptibility of CF AECs to ferroptosis is linked to abnormal intracellular ferrous iron accumulation and reduced antioxidant defences. In addition, the process of ferroptotic cell death in CF AECs does not appear to be a single entity and for the first time we describe necroptosis as a potential contributory factor. Iron chelation and antioxidant treatments may be promising therapeutic interventions in cystic fibrosis.
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Affiliation(s)
- Pramila Maniam
- Immunology Department, QIMR Berghofer Medical Research Institute, Brisbane, Australia
| | - Ama-Tawiah Essilfie
- Immunology Department, QIMR Berghofer Medical Research Institute, Brisbane, Australia
| | - Murugan Kalimutho
- Cell and Molecular Biology Department, QIMR Berghofer Medical Research Institute, Brisbane, Australia
| | - Dora Ling
- Immunology Department, QIMR Berghofer Medical Research Institute, Brisbane, Australia
| | - David M Frazer
- Cell and Molecular Biology Department, QIMR Berghofer Medical Research Institute, Brisbane, Australia
| | - Simon Phipps
- Immunology Department, QIMR Berghofer Medical Research Institute, Brisbane, Australia
| | - Gregory J Anderson
- Cell and Molecular Biology Department, QIMR Berghofer Medical Research Institute, Brisbane, Australia
- School of Chemistry and Molecular Bioscience, University of Queensland, St Lucia, Australia
| | - David W Reid
- Immunology Department, QIMR Berghofer Medical Research Institute, Brisbane, Australia.
- Adult Cystic Fibrosis Centre, The Prince Charles Hospital, Chermside, Australia.
- Lung Inflammation and Infection Laboratory, Immunology Department, QIMR Berghofer Medical Research Institute, Herston, QLD, 4003, Australia.
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9
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Li S, Zhang H, Chang J, Li D, Cao P. Iron overload and mitochondrial dysfunction orchestrate pulmonary fibrosis. Eur J Pharmacol 2021; 912:174613. [PMID: 34740581 DOI: 10.1016/j.ejphar.2021.174613] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Revised: 09/06/2021] [Accepted: 09/11/2021] [Indexed: 12/26/2022]
Abstract
Pulmonary fibrosis (PF) is a chronic, progressive heterogeneous disease of lung tissues with poor lung function caused by scar tissue. Due to our limited understanding of its mechanism, there is currently no treatment strategy that can prevent the development of PF. In recent years, iron accumulation and mitochondrial damage have been reported to participate in PF, and drugs that reduce iron content and improve mitochondrial function have shown significant efficacy in animal experimental models. Excessive iron leads to mitochondrial impairment, which may be the key cause that results in the dysfunction of various kinds of pulmonary cells and further promotes PF. As an emerging research hotspot, there are few targeted effective therapeutic strategies at present due to limited mechanistic understanding. In this review, the roles of iron homeostasis imbalance and mitochondrial damage in PF are summarized and discussed, highlighting a promising direction for finding truly effective therapeutics for PF.
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Affiliation(s)
- Shuxin Li
- Ministry of Education Key Laboratory of Molecular and Cellular Biology, Key Laboratory of Animal Physiology, Biochemistry and Molecular Biology of Hebei Province, College of Life Sciences, Hebei Normal University, Shijiazhuang, Hebei, 050024, People's Republic of China
| | - Hongmin Zhang
- Ministry of Education Key Laboratory of Molecular and Cellular Biology, Key Laboratory of Animal Physiology, Biochemistry and Molecular Biology of Hebei Province, College of Life Sciences, Hebei Normal University, Shijiazhuang, Hebei, 050024, People's Republic of China
| | - Jing Chang
- Ministry of Education Key Laboratory of Molecular and Cellular Biology, Key Laboratory of Animal Physiology, Biochemistry and Molecular Biology of Hebei Province, College of Life Sciences, Hebei Normal University, Shijiazhuang, Hebei, 050024, People's Republic of China
| | - Dongming Li
- Ministry of Education Key Laboratory of Molecular and Cellular Biology, Key Laboratory of Animal Physiology, Biochemistry and Molecular Biology of Hebei Province, College of Life Sciences, Hebei Normal University, Shijiazhuang, Hebei, 050024, People's Republic of China.
| | - Pengxiu Cao
- Ministry of Education Key Laboratory of Molecular and Cellular Biology, Key Laboratory of Animal Physiology, Biochemistry and Molecular Biology of Hebei Province, College of Life Sciences, Hebei Normal University, Shijiazhuang, Hebei, 050024, People's Republic of China.
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10
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Hwang W, Yong JH, Min KB, Lee KM, Pascoe B, Sheppard SK, Yoon SS. Genome-wide association study of signature genetic alterations among pseudomonas aeruginosa cystic fibrosis isolates. PLoS Pathog 2021; 17:e1009681. [PMID: 34161396 PMCID: PMC8274868 DOI: 10.1371/journal.ppat.1009681] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Revised: 07/12/2021] [Accepted: 05/31/2021] [Indexed: 12/18/2022] Open
Abstract
Pseudomonas aeruginosa (PA) is an opportunistic pathogen that causes diverse human infections including chronic airway infection in patients with cystic fibrosis (CF). Comparing the genomes of CF and non-CF PA isolates has great potential to identify the genetic basis of pathogenicity. To gain a deeper understanding of PA adaptation in CF airways, we performed a genome-wide association study (GWAS) on 1,001 PA genomes. Genetic variations identified among CF isolates were categorized into (i) alterations in protein-coding regions, either large- or small-scale, and (ii) polymorphic variation in intergenic regions. We introduced each CF-associated genetic alteration into the genome of PAO1, a prototype PA strain, and validated the outcomes experimentally. Loci readily mutated among CF isolates included genes encoding a probable sulfatase, a probable TonB-dependent receptor (PA2332~PA2336), L-cystine transporter (YecS, PA0313), and a probable transcriptional regulator (PA5438). A promoter region of a heme/hemoglobin uptake outer membrane receptor (PhuR, PA4710) was also different between the CF and non-CF isolate groups. Our analysis highlights ways in which the PA genome evolves to survive and persist within the context of chronic CF infection.
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Affiliation(s)
- Wontae Hwang
- Department of Microbiology and Immunology, Seoul, Republic of Korea
- Brain Korea 21 PLUS Project for Medical Sciences, Seoul, Republic of Korea
| | - Ji Hyun Yong
- Department of Microbiology and Immunology, Seoul, Republic of Korea
- Brain Korea 21 PLUS Project for Medical Sciences, Seoul, Republic of Korea
| | - Kyung Bae Min
- Department of Microbiology and Immunology, Seoul, Republic of Korea
- Brain Korea 21 PLUS Project for Medical Sciences, Seoul, Republic of Korea
| | - Kang-Mu Lee
- Department of Microbiology and Immunology, Seoul, Republic of Korea
- Brain Korea 21 PLUS Project for Medical Sciences, Seoul, Republic of Korea
| | - Ben Pascoe
- The Milner Centre for Evolution, Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath, United Kingdom
| | - Samuel K Sheppard
- The Milner Centre for Evolution, Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath, United Kingdom
| | - Sang Sun Yoon
- Department of Microbiology and Immunology, Seoul, Republic of Korea
- Brain Korea 21 PLUS Project for Medical Sciences, Seoul, Republic of Korea
- Institute for Immunology and Immunological Diseases, Seoul, Republic of Korea
- Severance Biomedical Science Institute, Yonsei University College of Medicine, Seoul, Republic of Korea
- * E-mail:
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11
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Deferasirox, an Iron-Chelating Agent, Improves Testicular Morphometric and Sperm Functional Parameters in a Rat Model of Varicocele. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2021; 2021:6698482. [PMID: 33897943 PMCID: PMC8052147 DOI: 10.1155/2021/6698482] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/01/2020] [Revised: 03/17/2021] [Accepted: 03/26/2021] [Indexed: 12/13/2022]
Abstract
Varicocele is characterized by testicular dysfunction that originates from hyperthermia and hypoxia, leading to defects in testicular tissue and altered spermatozoa structure and function. The varicocele testis is characterized by the presence of intracellular iron deposits that contribute to the associated oxidative stress. Therefore, we tested the hypothesis that administration of an iron-chelating agent, such as deferasirox (DFX), could potentially mitigate the consequences of varicocele on testicular tissue and spermatozoa. Using a well-established rat model of varicocele (VCL), we show that treatment with DFX partially improved the structure and function of the testis and spermatozoa. In particular, sperm motility was markedly restored whereas abnormal sperm morphology was only partially improved. No significant improvement in sperm count was observed that could be associated with the proapoptotic response observed following iron chelation treatment. No reduction in oxidative damage to spermatozoa was observed since lipid peroxidation and DNA integrity were not modified. This was suggested to be a result of increased oxidative stress. Finally, we also saw no indication of attenuation of the endoplasmic reticulum/unfolded protein (ER/UPR) stress response that we recently found associated with the VCL testis in rats.
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12
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Gifford AH, Polineni D, He J, D'Amico JL, Dorman DB, Williams MA, Nymon AB, Balwan A, Budden T, Zuckerman JB. A pilot study of cystic fibrosis exacerbation response phenotypes reveals contrasting serum and sputum iron trends. Sci Rep 2021; 11:4897. [PMID: 33649353 PMCID: PMC7921142 DOI: 10.1038/s41598-021-84041-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2020] [Accepted: 02/11/2021] [Indexed: 11/09/2022] Open
Abstract
The cystic fibrosis (CF) community seeks to explain heterogeneous outcomes of pulmonary exacerbation (PEX) treatment. Serum and sputum inflammatory mediators may identify people with CF (PwCF) at risk for suboptimal responses. However, lack of an established association between response phenotypes and these mediators limits clinical application. In this pilot study, we prospectively characterized treatment response phenotypes by assessing health-related quality-of-life (HRQoL) during PEX. We also measured lung function and iron-related biochemical parameters in serum and sputum. We classified subjects as sustained symptom-responders (SRs) or non-sustained symptom-responders (NSRs) based on the absence or presence, respectively, of worsened symptom scores after initial improvement. We used linear mixed models (LMMs) to determine whether trends in lung function, hematologic, serum, and sputum indices of inflammation differed between response cohorts. In 20 PwCF, we identified 10 SRs and 10 NSRs with no significant differences in lung function at PEX onset and treatment durations. SRs had better model-predicted trends in lung function than NSRs during PEX. Non-linear trends in serum and sputum iron levels significantly differed between SRs and NSRs. In adults with cystic fibrosis, PEX treatment response phenotypes may be correlated with distinctive trends in serum and sputum iron concentrations.
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Affiliation(s)
- Alex H Gifford
- Section of Pulmonary Medicine, 5C, Dartmouth-Hitchcock Medical Center, One Medical Center Drive, Lebanon, NH, 03756, USA.
| | - Deepika Polineni
- Division of Pulmonary, Critical Care and Sleep Medicine, University of Kansas Medical Center, 3901 Rainbow Boulevard, Mailstop 3007, Kansas City, KS, 66160, USA.
| | - Jianghua He
- Biostatistics and Data Science, University of Kansas Medical Center, Kansas City, KS, USA
| | - Jessica L D'Amico
- Pulmonary and Critical Care Medicine, Maine Medical Center, Portland, ME, USA
| | - Dana B Dorman
- Section of Pulmonary Medicine, 5C, Dartmouth-Hitchcock Medical Center, One Medical Center Drive, Lebanon, NH, 03756, USA
| | - Molly A Williams
- Section of Pulmonary Medicine, 5C, Dartmouth-Hitchcock Medical Center, One Medical Center Drive, Lebanon, NH, 03756, USA
| | - Amanda B Nymon
- Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, NH, USA
| | - Akshu Balwan
- Pulmonary and Critical Care Medicine, University of New Mexico, Albuquerque, NM, USA
| | - Theodore Budden
- Division of Pulmonary, Critical Care and Sleep Medicine, University of Kansas Medical Center, 3901 Rainbow Boulevard, Mailstop 3007, Kansas City, KS, 66160, USA
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13
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Veltman M, De Sanctis JB, Stolarczyk M, Klymiuk N, Bähr A, Brouwer RW, Oole E, Shah J, Ozdian T, Liao J, Martini C, Radzioch D, Hanrahan JW, Scholte BJ. CFTR Correctors and Antioxidants Partially Normalize Lipid Imbalance but not Abnormal Basal Inflammatory Cytokine Profile in CF Bronchial Epithelial Cells. Front Physiol 2021; 12:619442. [PMID: 33613309 PMCID: PMC7891400 DOI: 10.3389/fphys.2021.619442] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Accepted: 01/07/2021] [Indexed: 12/20/2022] Open
Abstract
A deficiency in cystic fibrosis transmembrane conductance regulator (CFTR) function in CF leads to chronic lung disease. CF is associated with abnormalities in fatty acids, ceramides, and cholesterol, their relationship with CF lung pathology is not completely understood. Therefore, we examined the impact of CFTR deficiency on lipid metabolism and pro-inflammatory signaling in airway epithelium using mass spectrometric, protein array. We observed a striking imbalance in fatty acid and ceramide metabolism, associated with chronic oxidative stress under basal conditions in CF mouse lung and well-differentiated bronchial epithelial cell cultures of CFTR knock out pig and CF patients. Cell-autonomous features of all three CF models included high ratios of ω-6- to ω-3-polyunsaturated fatty acids and of long- to very long-chain ceramide species (LCC/VLCC), reduced levels of total ceramides and ceramide precursors. In addition to the retinoic acid analog fenretinide, the anti-oxidants glutathione (GSH) and deferoxamine partially corrected the lipid profile indicating that oxidative stress may promote the lipid abnormalities. CFTR-targeted modulators reduced the lipid imbalance and oxidative stress, confirming the CFTR dependence of lipid ratios. However, despite functional correction of CF cells up to 60% of non-CF in Ussing chamber experiments, a 72-h triple compound treatment (elexacaftor/tezacaftor/ivacaftor surrogate) did not completely normalize lipid imbalance or oxidative stress. Protein array analysis revealed differential expression and shedding of cytokines and growth factors from CF epithelial cells compared to non-CF cells, consistent with sterile inflammation and tissue remodeling under basal conditions, including enhanced secretion of the neutrophil activator CXCL5, and the T-cell activator CCL17. However, treatment with antioxidants or CFTR modulators that mimic the approved combination therapies, ivacaftor/lumacaftor and ivacaftor/tezacaftor/elexacaftor, did not effectively suppress the inflammatory phenotype. We propose that CFTR deficiency causes oxidative stress in CF airway epithelium, affecting multiple bioactive lipid metabolic pathways, which likely play a role in CF lung disease progression. A combination of anti-oxidant, anti-inflammatory and CFTR targeted therapeutics may be required for full correction of the CF phenotype.
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Affiliation(s)
- Mieke Veltman
- Cell Biology Department, Erasmus Medical Center, Rotterdam, Netherlands.,Pediatric Pulmonology, Sophia Children's Hospital, Erasmus Medical Center, Rotterdam, Netherlands
| | - Juan B De Sanctis
- Faculty of Medicine and Dentistry, Institute of Molecular and Translational Medicine, Palacký University, Olomouc, Czechia
| | - Marta Stolarczyk
- Cell Biology Department, Erasmus Medical Center, Rotterdam, Netherlands
| | - Nikolai Klymiuk
- Large Animal Models for Cardiovascular Research, TU Munich, Munich, Germany.,Center for Innovative Medical Models, LMU Munich, Munich, Germany
| | - Andrea Bähr
- Large Animal Models for Cardiovascular Research, TU Munich, Munich, Germany.,Center for Innovative Medical Models, LMU Munich, Munich, Germany
| | - Rutger W Brouwer
- Cell Biology Department, Erasmus Medical Center, Rotterdam, Netherlands.,Center for Biomics, Erasmus Medical Center, Rotterdam, Netherlands
| | - Edwin Oole
- Cell Biology Department, Erasmus Medical Center, Rotterdam, Netherlands.,Center for Biomics, Erasmus Medical Center, Rotterdam, Netherlands
| | - Juhi Shah
- Department of Medicine, The Research Institute of the McGill University Health Centre, McGill University, Montreal, QC, Canada
| | - Tomas Ozdian
- Faculty of Medicine and Dentistry, Institute of Molecular and Translational Medicine, Palacký University, Olomouc, Czechia
| | - Jie Liao
- Department of Physiology, CF Translational Research Centre, McGill University, Montreal, QC, Canada
| | - Carolina Martini
- Department of Physiology, CF Translational Research Centre, McGill University, Montreal, QC, Canada
| | - Danuta Radzioch
- Department of Medicine, The Research Institute of the McGill University Health Centre, McGill University, Montreal, QC, Canada
| | - John W Hanrahan
- Department of Medicine, The Research Institute of the McGill University Health Centre, McGill University, Montreal, QC, Canada.,Department of Physiology, CF Translational Research Centre, McGill University, Montreal, QC, Canada
| | - Bob J Scholte
- Cell Biology Department, Erasmus Medical Center, Rotterdam, Netherlands.,Pediatric Pulmonology, Sophia Children's Hospital, Erasmus Medical Center, Rotterdam, Netherlands
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14
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Macrophage metabolic reprogramming during chronic lung disease. Mucosal Immunol 2021; 14:282-295. [PMID: 33184475 PMCID: PMC7658438 DOI: 10.1038/s41385-020-00356-5] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 10/13/2020] [Accepted: 10/24/2020] [Indexed: 02/04/2023]
Abstract
Airway macrophages (AMs) play key roles in the maintenance of lung immune tolerance. Tissue tailored, highly specialised and strategically positioned, AMs are critical sentinels of lung homoeostasis. In the last decade, there has been a revolution in our understanding of how metabolism underlies key macrophage functions. While these initial observations were made during steady state or using in vitro polarised macrophages, recent studies have indicated that during many chronic lung diseases (CLDs), AMs adapt their metabolic profile to fit their local niche. By generating reactive oxygen species (ROS) for pathogen defence, utilising aerobic glycolysis to rapidly generate cytokines, and employing mitochondrial respiration to fuel inflammatory responses, AMs utilise metabolic reprogramming for host defence, although these changes may also support chronic pathology. This review focuses on how metabolic alterations underlie AM phenotype and function during CLDs. Particular emphasis is given to how our new understanding of AM metabolic plasticity may be exploited to develop AM-focused therapies.
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15
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Zygiel EM, Obisesan AO, Nelson CE, Oglesby AG, Nolan EM. Heme protects Pseudomonas aeruginosa and Staphylococcus aureus from calprotectin-induced iron starvation. J Biol Chem 2020; 296:100160. [PMID: 33273016 PMCID: PMC7948498 DOI: 10.1074/jbc.ra120.015975] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Revised: 11/25/2020] [Accepted: 12/03/2020] [Indexed: 11/13/2022] Open
Abstract
Pseudomonas aeruginosa and Staphylococcus aureus are opportunistic bacterial pathogens that cause severe infections in immunocompromised individuals and patients with cystic fibrosis. Both P. aeruginosa and S. aureus require iron to infect the mammalian host. To obtain iron, these pathogens may rely on siderophore-mediated ferric iron uptake, ferrous iron uptake, or heme uptake at different points during infection. The preferred iron source depends on environmental conditions, including the presence of iron-sequestering host-defense proteins. Here, we investigate how the presence of heme, a highly relevant iron source during infection, affects bacterial responses to iron withholding by the innate immune protein calprotectin (CP). Prior work has shown that P. aeruginosa is starved of iron in the presence of CP. We report that P. aeruginosa upregulates expression of heme uptake machinery in response to CP. Furthermore, we show that heme protects P. aeruginosa from CP-mediated inhibition of iron uptake and iron-starvation responses. We extend our study to a second bacterial pathogen, S. aureus, and demonstrate that CP also inhibits iron uptake and induces iron-starvation responses by this pathogen. Similarly to P. aeruginosa, we show that heme protects S. aureus from CP-mediated inhibition of iron uptake and iron-starvation responses. These findings expand our understanding of microbial responses to iron sequestration by CP and highlight the importance of heme utilization for bacterial adaptation to host iron-withholding strategies.
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Affiliation(s)
- Emily M Zygiel
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Adunoluwa O Obisesan
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Cassandra E Nelson
- School of Pharmacy, Department of Pharmaceutical Sciences, University of Maryland, Baltimore, Maryland, USA
| | - Amanda G Oglesby
- School of Pharmacy, Department of Pharmaceutical Sciences, University of Maryland, Baltimore, Maryland, USA; School of Medicine, Department of Microbiology and Immunology, University of Maryland, Baltimore, Maryland, USA.
| | - Elizabeth M Nolan
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA.
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16
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Mancinelli R, Cutone A, Rosa L, Lepanto MS, Onori P, Pannarale L, Franchitto A, Gaudio E, Valenti P. Different iron-handling in inflamed small and large cholangiocytes and in small and large-duct type intrahepatic cholangiocarcinoma. Eur J Histochem 2020; 64. [PMID: 33131269 PMCID: PMC7586138 DOI: 10.4081/ejh.2020.3156] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Accepted: 09/14/2020] [Indexed: 12/15/2022] Open
Abstract
Cholangiocarcinoma (CCA) represents the second most common primary hepatic malignancy and originates from the neoplastic transformation of the biliary cells. The intrahepatic subtype includes two morpho-molecular forms: large-duct type intrahepatic CCA (iCCA) and small-duct type iCCA. Iron is fundamental for the cellular processes, contributing in tumor development and progression. The aim of this study was to evaluate iron uptake, storage, and efflux proteins in both lipopolysaccharide-inflamed small and large cholangiocytes as well as in different iCCA subtypes. Our results show that, despite an increase in interleukin-6 production by both small and large cholangiocytes, ferroportin (Fpn) was decreased only in small cholangiocytes, whereas transferrin receptor-1 (TfR1) and ferritin (Ftn) did not show any change. Differently from in vitro models, Fpn expression was increased in malignant cholangiocytes of small-duct type iCCA in comparison to large-duct type iCCA and peritumoral tissues. TfR1, Ftn and hepcidin were enhanced, even if at different extent, in both malignant cholangiocytes in comparison to the surrounding samples. Lactoferrin was higher in large-duct type iCCA in respect to small-duct type iCCA and peritumoral tissues. These findings show a different iron handling by inflamed small and large cholangiocytes, and small and large-duct type iCCA. The difference in iron homeostasis by the iCCA subtypes may have implications for the tumor management.
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Affiliation(s)
- Romina Mancinelli
- Department of Anatomical, Histological, Forensic Medicine and Orthopedic Sciences, Sapienza University of Rome.
| | - Antimo Cutone
- Department of Biosciences and Territory, University of Molise, Pesche (IS).
| | - Luigi Rosa
- Department of Public Health and Infectious Diseases, Sapienza University of Rome.
| | | | - Paolo Onori
- Department of Anatomical, Histological, Forensic Medicine and Orthopedic Sciences, Sapienza University of Rome .
| | - Luigi Pannarale
- Department of Anatomical, Histological, Forensic Medicine and Orthopedic Sciences, Sapienza University of Rome .
| | - Antonio Franchitto
- Department of Anatomical, Histological, Forensic Medicine and Orthopedic Sciences, Sapienza University of Rome; Eleonora Lorillard Spencer Cenci Foundation, Rome.
| | - Eugenio Gaudio
- Department of Anatomical, Histological, Forensic Medicine and Orthopedic Sciences, Sapienza University of Rome .
| | - Piera Valenti
- Department of Public Health and Infectious Diseases, Sapienza University of Rome.
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17
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Di Pietro C, Öz HH, Murray TS, Bruscia EM. Targeting the Heme Oxygenase 1/Carbon Monoxide Pathway to Resolve Lung Hyper-Inflammation and Restore a Regulated Immune Response in Cystic Fibrosis. Front Pharmacol 2020; 11:1059. [PMID: 32760278 PMCID: PMC7372134 DOI: 10.3389/fphar.2020.01059] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Accepted: 06/30/2020] [Indexed: 12/11/2022] Open
Abstract
In individuals with cystic fibrosis (CF), lung hyper-inflammation starts early in life and is perpetuated by mucus obstruction and persistent bacterial infections. The continuous tissue damage and scarring caused by non-resolving inflammation leads to bronchiectasis and, ultimately, respiratory failure. Macrophages (MΦs) are key regulators of immune response and host defense. We and others have shown that, in CF, MΦs are hyper-inflammatory and exhibit reduced bactericidal activity. Thus, MΦs contribute to the inability of CF lung tissues to control the inflammatory response or restore tissue homeostasis. The non-resolving hyper-inflammation in CF lungs is attributed to an impairment of several signaling pathways associated with resolution of the inflammatory response, including the heme oxygenase-1/carbon monoxide (HO-1/CO) pathway. HO-1 is an enzyme that degrades heme groups, leading to the production of potent antioxidant, anti-inflammatory, and bactericidal mediators, such as biliverdin, bilirubin, and CO. This pathway is fundamental to re-establishing cellular homeostasis in response to various insults, such as oxidative stress and infection. Monocytes/MΦs rely on abundant induction of the HO-1/CO pathway for a controlled immune response and for potent bactericidal activity. Here, we discuss studies showing that blunted HO-1 activation in CF-affected cells contributes to hyper-inflammation and defective host defense against bacteria. We dissect potential cellular mechanisms that may lead to decreased HO-1 induction in CF cells. We review literature suggesting that induction of HO-1 may be beneficial for the treatment of CF lung disease. Finally, we discuss recent studies highlighting how endogenous HO-1 can be induced by administration of controlled doses of CO to reduce lung hyper-inflammation, oxidative stress, bacterial infection, and dysfunctional ion transport, which are all hallmarks of CF lung disease.
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Affiliation(s)
| | | | | | - Emanuela M. Bruscia
- Department of Pediatrics, Yale University School of Medicine, New Haven, CT, United States
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18
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Voynow JA, Zheng S, Kummarapurugu AB. Glycosaminoglycans as Multifunctional Anti-Elastase and Anti-Inflammatory Drugs in Cystic Fibrosis Lung Disease. Front Pharmacol 2020; 11:1011. [PMID: 32733248 PMCID: PMC7360816 DOI: 10.3389/fphar.2020.01011] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Accepted: 06/23/2020] [Indexed: 12/28/2022] Open
Abstract
Neutrophil elastase (NE) is a major protease in the airways of patients with cystic fibrosis (CF) that activates airway inflammation by several mechanisms. NE stimulates epithelial toll like receptors (TLR) resulting in cytokine upregulation and release, upregulates MUC5AC, a major airway mucin, degrades both phagocytic receptors and opsonins resulting in both neutrophil and macrophage phagocytic failure, generates oxidative stress via extracellular generation and uptake of heme free iron, and activates other proteases. Altogether, these mechanisms create a significant inflammatory challenge that impairs innate immune function and results in airway remodeling. Currently, a major gap in our therapeutic approach to CF lung disease is the lack of an effective therapeutic strategy targeting active NE and its downstream pro-inflammatory sequelae. Polysulfated glycosaminoglycans (GAGs) are potent anti-elastase drugs that have additional anti-inflammatory properties. Heparin is a prototype of a glycosaminoglycan with both anti-elastase and anti-inflammatory properties. Heparin inhibits NE in an allosteric manner with high potency. Heparin also inhibits cathepsin G, blocks P-selectin and L-selectin, hinders ligand binding to the receptor for advanced glycation endproducts, and impedes histone acetyltransferase activity which dampens cytokine transcription and High Mobility Group Box 1 release. Furthermore, nebulized heparin treatment improves outcomes for patients with chronic obstructive pulmonary disease (COPD), asthma, acute lung injury and smoke inhalation. However, the anticoagulant activity of heparin is a potential contraindication for this therapy to be developed for CF lung disease. Therefore, modified heparins and other GAGs are being developed that retain the anti-elastase and anti-inflammatory qualities of heparin with minimal to no anticoagulant activity. The modified heparin, 2-O, 3-O desulfated heparin (ODSH), maintains anti-elastase and anti-inflammatory activities in vitro and in vivo, and has little residual anticoagulant activity. Heparan sulfate with O-sulfate residues but not N-sulfate residues blocks allergic asthmatic inflammation in a murine model. Polysulfated hyaluronic acid abrogates allergen- triggered rhinosinusitis in a murine model. Finally, nonsaccharide glycosaminoglycan mimetics with specific sulfate modifications can be designed to inhibit NE activity. Altogether, these novel GAGs or GAG mimetics hold significant promise to address the unmet need for inhaled anti-elastase and anti-inflammatory therapy for patients with CF.
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Affiliation(s)
- Judith A Voynow
- Department of Pediatric Pulmonology, Children's Hospital of Richmond at VCU, Richmond, VA, United States
| | - Shuo Zheng
- Department of Pediatric Pulmonology, Children's Hospital of Richmond at VCU, Richmond, VA, United States
| | - Apparao B Kummarapurugu
- Department of Pediatric Pulmonology, Children's Hospital of Richmond at VCU, Richmond, VA, United States
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19
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Altered iron metabolism in cystic fibrosis macrophages: the impact of CFTR modulators and implications for Pseudomonas aeruginosa survival. Sci Rep 2020; 10:10935. [PMID: 32616918 PMCID: PMC7331733 DOI: 10.1038/s41598-020-67729-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Accepted: 06/02/2020] [Indexed: 12/21/2022] Open
Abstract
Cystic fibrosis (CF) is a genetic disease caused by mutations in the CF transmembrane conductance regulator (CFTR) gene, resulting in chronic bacterial lung infections and tissue damage. CF macrophages exhibit reduced bacterial killing and increased inflammatory signaling. Iron is elevated in the CF lung and is a critical nutrient for bacteria, including the common CF pathogen Pseudomonas aeruginosa (Pa). While macrophages are a key regulatory component of extracellular iron, iron metabolism has yet to be characterized in human CF macrophages. Secreted and total protein levels were analyzed in non-CF and F508del/F508del CF monocyte derived macrophages (MDMs) with and without clinically approved CFTR modulators ivacaftor/lumacaftor. CF macrophage transferrin receptor 1 (TfR1) was reduced with ivacaftor/lumacaftor treatment. When activated with LPS, CF macrophage expressed reduced ferroportin (Fpn). After the addition of exogenous iron, total iron was elevated in conditioned media from CF MDMs and reduced in conditioned media from ivacaftor/lumacaftor treated CF MDMs. Pa biofilm formation and viability were elevated in conditioned media from CF MDMs and biofilm formation was reduced in the presence of conditioned media from ivacaftor/lumacaftor treated CF MDMs. Defects in iron metabolism observed in this study may inform host–pathogen interactions between CF macrophages and Pa.
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20
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McKelvey MC, Weldon S, McAuley DF, Mall MA, Taggart CC. Targeting Proteases in Cystic Fibrosis Lung Disease. Paradigms, Progress, and Potential. Am J Respir Crit Care Med 2020; 201:141-147. [PMID: 31626562 DOI: 10.1164/rccm.201906-1190pp] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Affiliation(s)
| | | | - Daniel F McAuley
- Wellcome-Wolfson Institute for Experimental Medicine, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, United Kingdom
| | - Marcus A Mall
- Department of Pediatric Pulmonology, Immunology and Intensive Care Medicine, Charité - Universitätsmedizin Berlin, Berlin, Germany.,Berlin Institute of Health, Berlin, Germany; and.,German Center for Lung Research, Berlin, Germany
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21
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O'Brien TJ, Welch M. Recapitulation of polymicrobial communities associated with cystic fibrosis airway infections: a perspective. Future Microbiol 2019; 14:1437-1450. [PMID: 31778075 DOI: 10.2217/fmb-2019-0200] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
The airways of persons with cystic fibrosis are prone to infection by a diverse and dynamic polymicrobial consortium. Currently, no models exist that permit recapitulation of this consortium within the laboratory. Such microbial ecosystems likely have a network of interspecies interactions, serving to modulate metabolic pathways and impact upon disease severity. The contribution of less abundant/fastidious microbial species on this cross-talk has often been neglected due to lack of experimental tractability. Here, we critically assess the existing models for studying polymicrobial infections. Particular attention is paid to 3Rs-compliant in vitro and in silico infection models, offering significant advantages over mammalian infection models. We outline why these models will likely become the 'go to' approaches when recapitulating polymicrobial cystic fibrosis infection.
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Affiliation(s)
- Thomas J O'Brien
- Department of Biochemistry, University of Cambridge, Cambridge, CB2 1QW, UK
| | - Martin Welch
- Department of Biochemistry, University of Cambridge, Cambridge, CB2 1QW, UK
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22
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O’Brien TJ, Welch M. A Continuous-Flow Model for in vitro Cultivation of Mixed Microbial Populations Associated With Cystic Fibrosis Airway Infections. Front Microbiol 2019; 10:2713. [PMID: 31824471 PMCID: PMC6883238 DOI: 10.3389/fmicb.2019.02713] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Accepted: 11/08/2019] [Indexed: 12/13/2022] Open
Abstract
The airways of people with cystic fibrosis (CF) provide a nutrient-rich environment which favours colonisation by a variety of bacteria and fungi. Although the dominant pathogen associated with CF airway infections is Pseudomonas aeruginosa, it is becoming increasingly clear that inter-species interactions between P. aeruginosa and other colonists in the airways may have a large impact on microbial physiology and virulence. However, there are currently no suitable experimental models that permit long-term co-culture of P. aeruginosa with other CF-associated pathogens. Here, we redress this problem by describing a "3R's-compliant" continuous-flow in vitro culture model which enables long-term co-culture of three representative CF-associated microbes: P. aeruginosa, Staphylococcus aureus and Candida albicans. Although these species rapidly out-compete one another when grown together or in pairs in batch culture, we show that in a continuously-fed setup, they can be maintained in a very stable, steady-state community. We use our system to show that even numerically (0.1%) minor species can have a major impact on intercellular signalling by P. aeruginosa. Importantly, we also show that co-culturing does not appear to influence species mutation rates, further reinforcing the notion that the system favours stability rather than divergence. The model is experimentally tractable and offers an inexpensive yet robust means of investigating inter-species interactions between CF pathogens.
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Affiliation(s)
| | - Martin Welch
- Department of Biochemistry, University of Cambridge, Cambridge, United Kingdom
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23
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Cutone A, Lepanto MS, Rosa L, Scotti MJ, Rossi A, Ranucci S, De Fino I, Bragonzi A, Valenti P, Musci G, Berlutti F. Aerosolized Bovine Lactoferrin Counteracts Infection, Inflammation and Iron Dysbalance in A Cystic Fibrosis Mouse Model of Pseudomonas aeruginosa Chronic Lung Infection. Int J Mol Sci 2019; 20:ijms20092128. [PMID: 31052156 PMCID: PMC6540064 DOI: 10.3390/ijms20092128] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Revised: 04/24/2019] [Accepted: 04/25/2019] [Indexed: 02/07/2023] Open
Abstract
Cystic fibrosis (CF) is a genetic disorder affecting several organs including airways. Bacterial infection, inflammation and iron dysbalance play a major role in the chronicity and severity of the lung pathology. The aim of this study was to investigate the effect of lactoferrin (Lf), a multifunctional iron-chelating glycoprotein of innate immunity, in a CF murine model of Pseudomonas aeruginosa chronic lung infection. To induce chronic lung infection, C57BL/6 mice, either cystic fibrosis transmembrane conductance regulator (CFTR)-deficient (Cftrtm1UNCTgN(FABPCFTR)#Jaw) or wild-type (WT), were intra-tracheally inoculated with multidrug-resistant MDR-RP73 P. aeruginosa embedded in agar beads. Treatments with aerosolized bovine Lf (bLf) or saline were started five minutes after infection and repeated daily for six days. Our results demonstrated that aerosolized bLf was effective in significantly reducing both pulmonary bacterial load and infiltrated leukocytes in infected CF mice. Furthermore, for the first time, we showed that bLf reduced pulmonary iron overload, in both WT and CF mice. In particular, at molecular level, a significant decrease of both the iron exporter ferroportin and iron storage ferritin, as well as luminal iron content was observed. Overall, bLf acts as a potent multi-targeting agent able to break the vicious cycle induced by P. aeruginosa, inflammation and iron dysbalance, thus mitigating the severity of CF-related pathology and sequelae.
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Affiliation(s)
- Antimo Cutone
- Department of Biosciences and Territory, University of Molise, 86090 Pesche, Italy.
- Department of Public Health and Infectious Diseases, University of Rome La Sapienza, 00185 Rome, Italy.
| | - Maria Stefania Lepanto
- Department of Public Health and Infectious Diseases, University of Rome La Sapienza, 00185 Rome, Italy.
| | - Luigi Rosa
- Department of Public Health and Infectious Diseases, University of Rome La Sapienza, 00185 Rome, Italy.
| | - Mellani Jinnett Scotti
- Department of Public Health and Infectious Diseases, University of Rome La Sapienza, 00185 Rome, Italy.
| | - Alice Rossi
- Infections and Cystic Fibrosis Unit, Division of Immunology, Transplantation and Infectious Diseases, IRCCS San Raffaele Scientific Institute, 20132 Milano, Italy.
| | - Serena Ranucci
- Infections and Cystic Fibrosis Unit, Division of Immunology, Transplantation and Infectious Diseases, IRCCS San Raffaele Scientific Institute, 20132 Milano, Italy.
| | - Ida De Fino
- Infections and Cystic Fibrosis Unit, Division of Immunology, Transplantation and Infectious Diseases, IRCCS San Raffaele Scientific Institute, 20132 Milano, Italy.
| | - Alessandra Bragonzi
- Infections and Cystic Fibrosis Unit, Division of Immunology, Transplantation and Infectious Diseases, IRCCS San Raffaele Scientific Institute, 20132 Milano, Italy.
| | - Piera Valenti
- Department of Public Health and Infectious Diseases, University of Rome La Sapienza, 00185 Rome, Italy.
| | - Giovanni Musci
- Department of Biosciences and Territory, University of Molise, 86090 Pesche, Italy.
| | - Francesca Berlutti
- Department of Public Health and Infectious Diseases, University of Rome La Sapienza, 00185 Rome, Italy.
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Iron Homeostasis in the Lungs-A Balance between Health and Disease. Pharmaceuticals (Basel) 2019; 12:ph12010005. [PMID: 30609678 PMCID: PMC6469191 DOI: 10.3390/ph12010005] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Revised: 12/23/2018] [Accepted: 12/25/2018] [Indexed: 12/15/2022] Open
Abstract
A strong mechanistic link between the regulation of iron homeostasis and oxygen sensing is evident in the lung, where both systems must be properly controlled to maintain lung function. Imbalances in pulmonary iron homeostasis are frequently associated with respiratory diseases, such as chronic obstructive pulmonary disease and with lung cancer. However, the underlying mechanisms causing alterations in iron levels and the involvement of iron in the development of lung disorders are incompletely understood. Here, we review current knowledge about the regulation of pulmonary iron homeostasis, its functional importance, and the link between dysregulated iron levels and lung diseases. Gaining greater knowledge on how iron contributes to the pathogenesis of these diseases holds promise for future iron-related therapeutic strategies.
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Andersen SB, Ghoul M, Marvig RL, Lee ZB, Molin S, Johansen HK, Griffin AS. Privatisation rescues function following loss of cooperation. eLife 2018; 7:e38594. [PMID: 30558711 PMCID: PMC6298776 DOI: 10.7554/elife.38594] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Accepted: 11/17/2018] [Indexed: 12/11/2022] Open
Abstract
A single cheating mutant can lead to the invasion and eventual eradication of cooperation from a population. Consequently, cheat invasion is often considered equal to extinction in empirical and theoretical studies of cooperator-cheat dynamics. But does cheat invasion necessarily equate extinction in nature? By following the social dynamics of iron metabolism in Pseudomonas aeruginosa during cystic fibrosis lung infection, we observed that individuals evolved to replace cooperation with a 'private' behaviour. Phenotypic assays showed that cooperative iron acquisition frequently was upregulated early in infection, which, however, increased the risk of cheat invasion. With whole-genome sequencing we showed that if, and only if, cooperative iron acquisition is lost from the population, a private system was upregulated. The benefit of upregulation depended on iron availability. These findings highlight the importance of social dynamics of natural populations and emphasizes the potential impact of past social interaction on the evolution of private traits.
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Affiliation(s)
- Sandra Breum Andersen
- Department of ZoologyUniversity of OxfordOxfordUnited Kingdom
- Novo Nordisk Foundation Center for BiosustainabilityTechnical University of DenmarkLyngbyDenmark
| | - Melanie Ghoul
- Department of ZoologyUniversity of OxfordOxfordUnited Kingdom
| | | | - Zhuo-Bin Lee
- Department of ZoologyUniversity of OxfordOxfordUnited Kingdom
| | - Søren Molin
- Novo Nordisk Foundation Center for BiosustainabilityTechnical University of DenmarkLyngbyDenmark
| | - Helle Krogh Johansen
- Department of Clinical MicrobiologyRigshospitaletCopenhagenDenmark
- Department of Clinical Medicine, Faculty of Health and Medical SciencesUniversity of CopenhagenCopenhagenDenmark
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26
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Ghio AJ, Madden MC, Esther CR. Transition and post-transition metals in exhaled breath condensate. J Breath Res 2018; 12:027112. [PMID: 29244031 DOI: 10.1088/1752-7163/aaa214] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Water vapor in expired air, as well as dispersed non-volatile components, condense onto a cooler surface after exiting the respiratory tract. This exhaled breath condensate (EBC) provides a dilute sampling of the epithelial lining fluid. Accordingly, the collection of EBC imparts a capacity to provide biomarkers of injury preceding clinical disease. Concentrations of transition and post-transition metals in EBC are included among these endpoints. Iron and zinc are the metals with the highest concentration and are measurable in all EBC samples from healthy subjects; other metals are most frequently either at or below the level of detection in this group. Gender, age, and smoking can impact EBC metal concentrations in healthy subjects. EBC metal concentrations among patients diagnosed with particular lung diseases (e.g. asthma, chronic obstructive disease, and interstitial lung disease) have been of research interest but no definite pattern of involvement has been delineated. Studies of occupationally exposed workers confirm significant exposure to specific metals, but such EBC metal measurements frequently provide evidence redundant with environmental sampling. Measurements of metal concentrations in EBC remain a research tool into metal homeostasis in the respiratory tract and participation of metals in disease pathogenesis. The quantification of metal concentrations in EBC is currently not reliable for clinical use in either supporting or determining any diagnosis. Issues that must be addressed prior to the use of EBC metal measurements include the establishment of both standardized collection and measurement techniques.
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Affiliation(s)
- Andrew J Ghio
- National Health and Environmental Effects Research Laboratory, Environmental Protection Agency, Chapel Hill NC, United States of America
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27
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Ali MK, Kim RY, Karim R, Mayall JR, Martin KL, Shahandeh A, Abbasian F, Starkey MR, Loustaud-Ratti V, Johnstone D, Milward EA, Hansbro PM, Horvat JC. Role of iron in the pathogenesis of respiratory disease. Int J Biochem Cell Biol 2017; 88:181-195. [PMID: 28495571 DOI: 10.1016/j.biocel.2017.05.003] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Revised: 05/01/2017] [Accepted: 05/03/2017] [Indexed: 12/13/2022]
Abstract
Iron is essential for many biological processes, however, too much or too little iron can result in a wide variety of pathological consequences, depending on the organ system, tissue or cell type affected. In order to reduce pathogenesis, iron levels are tightly controlled in throughout the body by regulatory systems that control iron absorption, systemic transport and cellular uptake and storage. Altered iron levels and/or dysregulated homeostasis have been associated with several lung diseases, including chronic obstructive pulmonary disease, lung cancer, cystic fibrosis, idiopathic pulmonary fibrosis and asthma. However, the mechanisms that underpin these associations and whether iron plays a key role in the pathogenesis of lung disease are yet to be fully elucidated. Furthermore, in order to survive and replicate, pathogenic micro-organisms have evolved strategies to source host iron, including freeing iron from cells and proteins that store and transport iron. To counter these microbial strategies, mammals have evolved immune-mediated defence mechanisms that reduce iron availability to pathogens. This interplay between iron, infection and immunity has important ramifications for the pathogenesis and management of human respiratory infections and diseases. An increased understanding of the role that iron plays in the pathogenesis of lung disease and respiratory infections may help inform novel therapeutic strategies. Here we review the clinical and experimental evidence that highlights the potential importance of iron in respiratory diseases and infections.
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Affiliation(s)
- Md Khadem Ali
- School of Biomedical Sciences and Pharmacy, Faculty of Health and Medicine, The University of Newcastle, Callaghan NSW 2308, Australia
| | - Richard Y Kim
- School of Biomedical Sciences and Pharmacy, Faculty of Health and Medicine, The University of Newcastle, Callaghan NSW 2308, Australia
| | - Rafia Karim
- School of Biomedical Sciences and Pharmacy, Faculty of Health and Medicine, The University of Newcastle, Callaghan NSW 2308, Australia
| | - Jemma R Mayall
- School of Biomedical Sciences and Pharmacy, Faculty of Health and Medicine, The University of Newcastle, Callaghan NSW 2308, Australia
| | - Kristy L Martin
- School of Biomedical Sciences and Pharmacy, Faculty of Health and Medicine, The University of Newcastle, Callaghan NSW 2308, Australia
| | - Ali Shahandeh
- School of Biomedical Sciences and Pharmacy, Faculty of Health and Medicine, The University of Newcastle, Callaghan NSW 2308, Australia
| | - Firouz Abbasian
- Global Centre for Environmental Remediation, Faculty of Science, the University of Newcastle, Callaghan, NSW 2308, Australia
| | - Malcolm R Starkey
- School of Biomedical Sciences and Pharmacy, Faculty of Health and Medicine, The University of Newcastle, Callaghan NSW 2308, Australia
| | | | - Daniel Johnstone
- Bosch Institute and Discipline of Physiology, The University of Sydney, Sydney NSW 2000, Australia
| | - Elizabeth A Milward
- School of Biomedical Sciences and Pharmacy, Faculty of Health and Medicine, The University of Newcastle, Callaghan NSW 2308, Australia
| | - Philip M Hansbro
- School of Biomedical Sciences and Pharmacy, Faculty of Health and Medicine, The University of Newcastle, Callaghan NSW 2308, Australia
| | - Jay C Horvat
- School of Biomedical Sciences and Pharmacy, Faculty of Health and Medicine, The University of Newcastle, Callaghan NSW 2308, Australia.
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Neves J, Leitz D, Kraut S, Brandenberger C, Agrawal R, Weissmann N, Mühlfeld C, Mall MA, Altamura S, Muckenthaler MU. Disruption of the Hepcidin/Ferroportin Regulatory System Causes Pulmonary Iron Overload and Restrictive Lung Disease. EBioMedicine 2017; 20:230-239. [PMID: 28499927 PMCID: PMC5478206 DOI: 10.1016/j.ebiom.2017.04.036] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Revised: 04/27/2017] [Accepted: 04/28/2017] [Indexed: 01/01/2023] Open
Abstract
Emerging evidence suggests that pulmonary iron accumulation is implicated in a spectrum of chronic lung diseases. However, the mechanism(s) involved in pulmonary iron deposition and its role in the in vivo pathogenesis of lung diseases remains unknown. Here we show that a point mutation in the murine ferroportin gene, which causes hereditary hemochromatosis type 4 (Slc40a1C326S), increases iron levels in alveolar macrophages, epithelial cells lining the conducting airways and lung parenchyma, and in vascular smooth muscle cells. Pulmonary iron overload is associated with oxidative stress, restrictive lung disease with decreased total lung capacity and reduced blood oxygen saturation in homozygous Slc40a1C326S/C326S mice compared to wild-type controls. These findings implicate iron in lung pathology, which is so far not considered a classical iron-related disorder. Ferroportin resistance to hepcidin binding leads to pulmonary iron overload. Lung iron accumulation is restricted to specific cell types. Iron overload causes restrictive lung disease and decreased blood oxygen saturation.
Pulmonary iron accumulation is associated with a wide spectrum of lung diseases, such as chronic obstructive pulmonary disease and cystic fibrosis. Impaired lung function was further reported in patients with thalassemia major, a disease hallmarked by transfusional iron overload. So far, the mechanism(s) leading to pulmonary iron deposition and its role in disease onset and progression are still unknown. Our study shows that in a murine disease model, in which the control of systemic iron homeostasis is disrupted, iron accumulates in the lung and correlates with oxidative stress, restrictive lung disease and decreased blood oxygen saturation. These findings implicate iron overload in lung pathology, which is not considered a classical iron-related disorder.
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Affiliation(s)
- Joana Neves
- Department of Pediatric Hematology, Oncology and Immunology - University of Heidelberg, Im Neuenheimer Feld 350, D-69120 Heidelberg, Germany; Molecular Medicine Partnership Unit, D-69120 Heidelberg, Germany; Graduate Program in Areas of Basic and Applied Biology, Abel Salazar Biomedical Sciences Institute, University of Porto, 4050-343 Porto, Portugal; Translational Lung Research Center Heidelberg (TLRC), German Center for Lung Research (DZL), University of Heidelberg, D-69120 Heidelberg, Germany
| | - Dominik Leitz
- Translational Lung Research Center Heidelberg (TLRC), German Center for Lung Research (DZL), University of Heidelberg, D-69120 Heidelberg, Germany; Department of Translational Pulmonology, University of Heidelberg, D-69120 Heidelberg, Germany
| | - Simone Kraut
- Justus-Liebig University of Giessen (JLUG), Excellence Cluster Cardiopulmonary System (ECCPS), Universities of Giessen and Marburg Lung Center (UGMLC), German Center for Lung Research (DZL), Germany
| | - Christina Brandenberger
- Institute of Functional and Applied Anatomy, Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), German Center for Lung Research (DZL), Hannover Medical School, D-30625 Hannover, Germany
| | - Raman Agrawal
- Translational Lung Research Center Heidelberg (TLRC), German Center for Lung Research (DZL), University of Heidelberg, D-69120 Heidelberg, Germany; Department of Translational Pulmonology, University of Heidelberg, D-69120 Heidelberg, Germany
| | - Norbert Weissmann
- Justus-Liebig University of Giessen (JLUG), Excellence Cluster Cardiopulmonary System (ECCPS), Universities of Giessen and Marburg Lung Center (UGMLC), German Center for Lung Research (DZL), Germany
| | - Christian Mühlfeld
- Institute of Functional and Applied Anatomy, Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), German Center for Lung Research (DZL), Hannover Medical School, D-30625 Hannover, Germany
| | - Marcus A Mall
- Molecular Medicine Partnership Unit, D-69120 Heidelberg, Germany; Translational Lung Research Center Heidelberg (TLRC), German Center for Lung Research (DZL), University of Heidelberg, D-69120 Heidelberg, Germany; Department of Translational Pulmonology, University of Heidelberg, D-69120 Heidelberg, Germany
| | - Sandro Altamura
- Department of Pediatric Hematology, Oncology and Immunology - University of Heidelberg, Im Neuenheimer Feld 350, D-69120 Heidelberg, Germany; Molecular Medicine Partnership Unit, D-69120 Heidelberg, Germany
| | - Martina U Muckenthaler
- Department of Pediatric Hematology, Oncology and Immunology - University of Heidelberg, Im Neuenheimer Feld 350, D-69120 Heidelberg, Germany; Molecular Medicine Partnership Unit, D-69120 Heidelberg, Germany; Translational Lung Research Center Heidelberg (TLRC), German Center for Lung Research (DZL), University of Heidelberg, D-69120 Heidelberg, Germany.
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Kido T, Morimoto Y, Yatera K, Ishimoto H, Ogoshi T, Oda K, Yamasaki K, Kawanami T, Shimajiri S, Mukae H. The utility of electron microscopy in detecting asbestos fibers and particles in BALF in diffuse lung diseases. BMC Pulm Med 2017; 17:71. [PMID: 28431523 PMCID: PMC5401470 DOI: 10.1186/s12890-017-0415-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Accepted: 04/18/2017] [Indexed: 12/03/2022] Open
Abstract
Background In patients with diffuse lung diseases, differentiating occupational lung diseases from other diseases is clinically important. However, the value of assessing asbestos and particles in bronchoalveolar lavage fluid (BALF) in diffuse lung diseases by electron microscopy (EM) remains unclear. We evaluated the utility of EM in detecting asbestos fibers and particles in patients with diffuse lung diseases. Methods The BALF specimens of 107 patients with diffuse lung diseases were evaluated. First, detection of asbestos by EM and light microscopy (LM) were compared. Second, the detection of asbestos using surgically obtained lung tissues of 8 of 107 patients were compared with the results of EM and LM in BALF. Third, we compared the results of mineralogical components of particles in patients with (n = 48) and without (n = 59) a history of occupational exposure to inorganic dust. Results BALF asbestos were detected in 11 of 48 patients with a history of occupational exposure by EM; whereas asbestos as asbestos bodies (ABs) were detected in BALF in 4 of these 11 patients by LM. Eight of 107 patients in whom lung tissue samples were surgically obtained, EM detected BALF asbestos at a level of >1,000 fibers/ml in all three patients who had ABs in lung tissue samples by LM at a level of >1,000 fibers/g. The BALF asbestos concentration by EM and in lung tissue by LM were positively correlated. The particle fractions of iron and phosphorus were increased in patients with a history of occupational exposure and both correlated with a history of occupational exposure by a multiple regression analysis. Conclusions EM using BALF seemed to be superior to LM using BALF and displayed a similar sensitivity to LM using surgically-obtained lung tissue samples in the detection of asbestos. Our results also suggest that detection of elements, such as iron and phosphorus in particles, is useful for evaluating occupational exposure. We conclude that the detection of asbestos and iron and phosphorus in particles in BALF by EM is very useful for the evaluation of occupational exposure.
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Affiliation(s)
- Takashi Kido
- Department of Respiratory Medicine, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu, Fukuoka, Japan.
| | - Yasuo Morimoto
- Department of Occupational Pneumology, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu, Fukuoka, Japan
| | - Kazuhiro Yatera
- Department of Respiratory Medicine, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu, Fukuoka, Japan
| | - Hiroshi Ishimoto
- Department of Respiratory Medicine, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu, Fukuoka, Japan
| | - Takaaki Ogoshi
- Department of Respiratory Medicine, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu, Fukuoka, Japan
| | - Keishi Oda
- Department of Respiratory Medicine, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu, Fukuoka, Japan
| | - Kei Yamasaki
- Department of Respiratory Medicine, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu, Fukuoka, Japan
| | - Toshinori Kawanami
- Department of Respiratory Medicine, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu, Fukuoka, Japan
| | - Shohei Shimajiri
- Second Department of Internal Medicine, Nagasaki University School of Medicine, 1-7-1 Sakamoto, Nagasaki, Japan
| | - Hiroshi Mukae
- Department of Respiratory Medicine, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu, Fukuoka, Japan
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30
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Quinn RA, Phelan VV, Whiteson KL, Garg N, Bailey BA, Lim YW, Conrad DJ, Dorrestein PC, Rohwer FL. Microbial, host and xenobiotic diversity in the cystic fibrosis sputum metabolome. THE ISME JOURNAL 2016; 10:1483-98. [PMID: 26623545 PMCID: PMC5029181 DOI: 10.1038/ismej.2015.207] [Citation(s) in RCA: 75] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/19/2015] [Revised: 10/19/2015] [Accepted: 10/12/2015] [Indexed: 12/21/2022]
Abstract
Cystic fibrosis (CF) lungs are filled with thick mucus that obstructs airways and facilitates chronic infections. Pseudomonas aeruginosa is a significant pathogen of this disease that produces a variety of toxic small molecules. We used molecular networking-based metabolomics to investigate the chemistry of CF sputa and assess how the microbial molecules detected reflect the microbiome and clinical culture history of the patients. Metabolites detected included xenobiotics, P. aeruginosa specialized metabolites and host sphingolipids. The clinical culture and microbiome profiles did not correspond to the detection of P. aeruginosa metabolites in the same samples. The P. aeruginosa molecules that were detected in sputum did not match those from laboratory cultures. The pseudomonas quinolone signal (PQS) was readily detectable from cultured strains, but absent from sputum, even when its precursor molecules were present. The lack of PQS production in vivo is potentially due to the chemical nature of the CF lung environment, indicating that culture-based studies of this pathogen may not explain its behavior in the lung. The most differentially abundant molecules between CF and non-CF sputum were sphingolipids, including sphingomyelins, ceramides and lactosylceramide. As these highly abundant molecules contain the inflammatory mediator ceramide, they may have a significant role in CF hyperinflammation. This study demonstrates that the chemical makeup of CF sputum is a complex milieu of microbial, host and xenobiotic molecules. Detection of a bacterium by clinical culturing and 16S rRNA gene profiling do not necessarily reflect the active production of metabolites from that bacterium in a sputum sample.
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Affiliation(s)
- Robert A Quinn
- Department of Biology, San Diego State
University, San Diego, CA, USA
- Skaggs School of Pharmacy and
Pharmaceutical Sciences, University of California at San Diego, La
Jolla, CA, USA
| | - Vanessa V Phelan
- Skaggs School of Pharmacy and
Pharmaceutical Sciences, University of California at San Diego, La
Jolla, CA, USA
| | - Katrine L Whiteson
- Department of Molecular Biology and
Biochemistry, University of California Irvine, Irvine,
CA, USA
| | - Neha Garg
- Skaggs School of Pharmacy and
Pharmaceutical Sciences, University of California at San Diego, La
Jolla, CA, USA
| | - Barbara A Bailey
- Department of Mathematics and Statistics,
San Diego State University, San Diego, CA,
USA
| | - Yan Wei Lim
- Department of Biology, San Diego State
University, San Diego, CA, USA
| | - Douglas J Conrad
- Department of Medicine, University of
California at San Diego, La Jolla, CA,
USA
| | - Pieter C Dorrestein
- Skaggs School of Pharmacy and
Pharmaceutical Sciences, University of California at San Diego, La
Jolla, CA, USA
| | - Forest L Rohwer
- Department of Biology, San Diego State
University, San Diego, CA, USA
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Chanvorachote P, Luanpitpong S. Iron induces cancer stem cells and aggressive phenotypes in human lung cancer cells. Am J Physiol Cell Physiol 2016; 310:C728-39. [DOI: 10.1152/ajpcell.00322.2015] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2015] [Accepted: 02/17/2016] [Indexed: 12/20/2022]
Abstract
Evidence has accumulated in support of the critical impact of cancer stem cells (CSCs) behind the chemotherapeutic failure, cancer metastasis, and subsequent disease recurrence and relapse, but knowledge of how CSCs are regulated is still limited. Redox status of the cells has been shown to dramatically influence cell signaling and CSC-like aggressive behaviors. Here, we investigated how subtoxic concentrations of iron, which have been found to specifically induce cellular hydroxyl radical, affected CSC-like subpopulations of human non-small cell lung carcinoma (NSCLC). We reveal for the first time that subchronic iron exposure and higher levels of hydroxyl radical correlated well with increased CSC-like phenotypes. The iron-exposed NSCLC H460 and H292 cells exhibited a remarkable increase in propensities to form CSC spheroids and to proliferate, migrate, and invade in parallel with an increase in level of a well-known CSC marker, ABCG2. We further observed that such phenotypic changes induced by iron were not related to an epithelial-to-mesenchymal transition (EMT). Instead, the sex-determining region Y (SRY)-box 9 protein (SOX9) was substantially linked to iron treatment and hydroxyl radical level. Using gene manipulations, including ectopic SOX9 overexpression and SOX9 short hairpin RNA knockdown, we have verified that SOX9 is responsible for CSC enrichment mediated by iron. These findings indicate a novel role of iron via hydroxyl radical in CSC regulation and its importance in aggressive cancer behaviors and likely metastasis through SOX9 upregulation.
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Affiliation(s)
- Pithi Chanvorachote
- Department of Pharmacology and Physiology, Faculty of Pharmaceutical Sciences, Chulalongkorn University, Bangkok, Thailand
- Cell-based Drug and Health Products Development Research Unit, Chulalongkorn University, Bangkok, Thailand; and
| | - Sudjit Luanpitpong
- Cell-based Drug and Health Products Development Research Unit, Chulalongkorn University, Bangkok, Thailand; and
- Siriraj Center of Excellence for Stem Cell Research, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
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On endocytosis of foreign ferritin and occurrence of phagolysosomes in fish heart endothelial cells. Acta Histochem 2016; 118:252-5. [PMID: 26852295 DOI: 10.1016/j.acthis.2016.01.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2015] [Revised: 01/05/2016] [Accepted: 01/25/2016] [Indexed: 12/20/2022]
Abstract
In the present study the ultrastructure and function of the endothelial cells enveloping the muscle trabeculae in heart in two teleosts, platyfish and firemouth cichlid, are described and discussed. These cells displayed a structure making them able to take up large amounts of foreign ferritin particles from the blood stream. The ferritin particles were assembled into huge phagolysosomes. Large amounts of Prussian blue were precipitated throughout these lysosomes when treated with acid ferrohexacyanide solution. The occurrence of Prussian blue precipitations in the control heart endothelial cells after Schmorl's solution, suggests that these cells normally contain undigestible material, a finding which strengthens the view that this tissue is involved in blood clearance in the present species. In conclusion, these heart endothelial cells seem able to perform a very efficient blood clearance of scavenger and foreign macromolecules and particles in the present species.
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Abstract
Cystic fibrosis (CF) lung disease is characterized by persistent and unresolved inflammation, with elevated proinflammatory and decreased anti-inflammatory cytokines, and greater numbers of immune cells. Hyperinflammation is recognized as a leading cause of lung tissue destruction in CF. Hyper-inflammation is not solely observed in the lungs of CF patients, since it may contribute to destruction of exocrine pancreas and, likely, to defects in gastrointestinal tract tissue integrity. Paradoxically, despite the robust inflammatory response, and elevated number of immune cells (such as neutrophils and macrophages), CF lungs fail to clear bacteria and are more susceptible to infections. Here, we have summarized the current understanding of immune dysregulation in CF, which may drive hyperinflammation and impaired host defense.
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Affiliation(s)
- Emanuela M Bruscia
- Section of Respiratory Medicine, Department of Pediatrics, Yale University School of Medicine, 330 Cedar Street, FMP, Room#524, New Haven, CT 06520, USA.
| | - Tracey L Bonfield
- Division of Pulmonology, Allergy and Immunology, Department of Pediatrics, Case Western Reserve University School of Medicine, 0900 Euclid Avenue, Cleveland, OH 44106-4948, USA.
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Cystic fibrosis and the war for iron at the host-pathogen battlefront. Proc Natl Acad Sci U S A 2016; 113:1480-2. [PMID: 26802119 DOI: 10.1073/pnas.1525101113] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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Deschemin JC, Allouche S, Brouillard F, Vaulont S. Iron Homeostasis and Inflammatory Status in Mice Deficient for the Cystic Fibrosis Transmembrane Regulator. PLoS One 2015; 10:e0145685. [PMID: 26709821 PMCID: PMC4699203 DOI: 10.1371/journal.pone.0145685] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Accepted: 12/07/2015] [Indexed: 12/27/2022] Open
Abstract
BACKGROUND Cystic Fibrosis (CF) is a frequent and lethal autosomal recessive disease caused by mutations in the gene encoding the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR). Patients with CF suffer from chronic infections and severe inflammation, which lead to progressive pulmonary and gut diseases. Recently, an expanding body of evidence has suggested that iron homeostasis was abnormal in CF with, in particular, systemic iron deficiency and iron sequestration in the epithelium airway. The molecular mechanisms responsible for iron dysregulation and the relationship with inflammation in CF are unknown. METHODS AND RESULTS We assessed the impact of CFTR deficiency on systemic and tissue iron homeostasis as well as inflammation in wildtype and CFTR knockout (KO) mice. First, in contrast to the systemic and intestinal inflammation we observed in the CFTR KO mice, we reported the absence of lung phenotype with regards to both inflammation and iron status. Second, we showed a significant decrease of plasma ferritin levels in the KO mice, as in CF patients, likely caused by a decrease in spleen ferritin levels. However, we measured unchanged plasma iron levels in the KO mice that may be explained by increased intestinal iron absorption. CONCLUSION These results indicate that in CF, the lung do not predominantly contributes to the systemic ferritin deficiency and we propose the spleen as the major organ responsible for hypoferritinemia in the KO mouse. These results should provide a better understanding of iron dysregulation in CF patients where treating or not iron deficiency remains a challenging question.
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Affiliation(s)
- Jean-Christophe Deschemin
- INSERM, U1016, Institut Cochin, Paris, France
- CNRS, UMR8104, Paris, France
- Université Paris Descartes, Sorbonne Paris Cité, Paris, France
- Laboratory of Excellence GR-Ex, Paris, France
| | - Sarah Allouche
- INSERM, U1016, Institut Cochin, Paris, France
- CNRS, UMR8104, Paris, France
- Université Paris Descartes, Sorbonne Paris Cité, Paris, France
- Laboratory of Excellence GR-Ex, Paris, France
| | - Franck Brouillard
- Université Paris Descartes, Sorbonne Paris Cité, Paris, France
- Institut de Chimie des Substances Naturelles, UPR2301 CNRS, Gif-sur-Yvette, France
| | - Sophie Vaulont
- INSERM, U1016, Institut Cochin, Paris, France
- CNRS, UMR8104, Paris, France
- Université Paris Descartes, Sorbonne Paris Cité, Paris, France
- Laboratory of Excellence GR-Ex, Paris, France
- * E-mail:
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Gifford AH, Dorman DB, Moulton LA, Helm JE, Griffin MM, MacKenzie TA. Serum Iron Level Is Associated with Time to Antibiotics in Cystic Fibrosis. Clin Transl Sci 2015; 8:754-8. [PMID: 26643575 DOI: 10.1111/cts.12358] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Serum levels of hepcidin-25, a peptide hormone that reduces blood iron content, are elevated when patients with cystic fibrosis (CF) develop pulmonary exacerbation (PEx). Because hepcidin-25 is unavailable as a clinical laboratory test, we questioned whether a one-time serum iron level was associated with the subsequent number of days until PEx, as defined by the need to receive systemic antibiotics (ABX) for health deterioration. METHODS Clinical, biochemical, and microbiological parameters were simultaneously checked in 54 adults with CF. Charts were reviewed to determine when they first experienced a PEx after these parameters were assessed. Time to ABX was compared in subgroups with and without specific attributes. Multivariate linear regression was used to identify parameters that significantly explained variation in time to ABX. RESULTS In univariate analyses, time to ABX was significantly shorter in subjects with Aspergillus-positive sputum cultures and CF-related diabetes. Multivariate linear regression models demonstrated that shorter time to ABX was associated with younger age, lower serum iron level, and Aspergillus sputum culture positivity. CONCLUSIONS Serum iron, age, and Aspergillus sputum culture positivity are factors associated with shorter time to subsequent PEx in CF adults.
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Affiliation(s)
- Alex H Gifford
- Department of Medicine, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire, USA
| | - Dana B Dorman
- Translational Research Core, Dartmouth Lung Biology Center, Lebanon, New Hampshire, USA
| | - Lisa A Moulton
- Translational Research Core, Dartmouth Lung Biology Center, Lebanon, New Hampshire, USA
| | - Jennifer E Helm
- Translational Research Core, Dartmouth Lung Biology Center, Lebanon, New Hampshire, USA
| | - Mary M Griffin
- Translational Research Core, Dartmouth Lung Biology Center, Lebanon, New Hampshire, USA
| | - Todd A MacKenzie
- Department of Community and Family Medicine, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA
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Tyrrell J, Callaghan M. Iron acquisition in the cystic fibrosis lung and potential for novel therapeutic strategies. MICROBIOLOGY-SGM 2015; 162:191-205. [PMID: 26643057 DOI: 10.1099/mic.0.000220] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Iron acquisition is vital to microbial survival and is implicated in the virulence of many of the pathogens that reside in the cystic fibrosis (CF) lung. The multifaceted nature of iron acquisition by both bacterial and fungal pathogens encompasses a range of conserved and species-specific mechanisms, including secretion of iron-binding siderophores, utilization of siderophores from other species, release of iron from host iron-binding proteins and haemoproteins, and ferrous iron uptake. Pathogens adapt and deploy specific systems depending on iron availability, bioavailability of the iron pool, stage of infection and presence of competing pathogens. Understanding the dynamics of pathogen iron acquisition has the potential to unveil new avenues for therapeutic intervention to treat both acute and chronic CF infections. Here, we examine the range of strategies utilized by the primary CF pathogens to acquire iron and discuss the different approaches to targeting iron acquisition systems as an antimicrobial strategy.
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Affiliation(s)
- Jean Tyrrell
- Centre of Microbial Host Interactions, Institute of Technology Tallaght, Dublin D24KT9, Ireland
| | - Máire Callaghan
- Centre of Microbial Host Interactions, Institute of Technology Tallaght, Dublin D24KT9, Ireland
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Papp Á, Bene Z, Gáspár I, Nagy B, Kádár L, Márialigeti T, Bánfi A, Baktai G, Balla G, Nagy B. Decreased VEGF Level Is Associated with Elevated Ferritin Concentration in Bronchoalveolar Lavage Fluid of Children with Interstitial Lung Diseases. Respiration 2015; 90:443-450. [PMID: 26473738 DOI: 10.1159/000440888] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2015] [Accepted: 09/01/2015] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND A decreased level of vascular endothelial growth factor (VEGF) was previously described in bronchoalveolar lavage fluid (BALF) of adults with interstitial lung diseases (ILD) due to bronchial epithelial cell apoptosis and its proteolytic degradation. Elevated intrapulmonary ferritin was produced by alveolar cells that promoted oxidative injury in such patients. OBJECTIVES In this study, we analyzed the concentrations of VEGF and ferritin in BALF samples of ILD children and studied the relationship between their levels and the degree of inflammation. METHODS BALF and serum concentration of VEGF as well as ferritin and albumin in BALF samples were measured using enzyme-linked immunosorbent assay in children with idiopathic interstitial pneumonia (n = 16), hypersensitivity pneumonitis (n = 11) and idiopathic pulmonary hemosiderosis (n = 3). Twenty-four age- and gender-matched subjects with suspicious foreign body aspiration served as a control group. RESULTS VEGF per albumin levels in BALF were significantly decreased in ILD children compared to controls (1,075 [784-1,415] pg/mg albumin vs. 2,741 [1,131-4,660] pg/mg albumin, p = 0.0008). These values showed a significant negative correlation with inflammatory markers of total immune cell count in BALF (r = -0.411, p = 0.002) and serum C-reactive protein (r = -0.367, p = 0.006). Although serum VEGF was augmented in ILD children versus controls, no difference was observed among the ILD groups. In addition, BALF ferritin/albumin level (688 [188-1,571] ng/mg albumin vs. 256 [178-350] ng/mg albumin, p = 0.022) was significantly higher than normal in ILD individuals, especially in idiopathic pulmonary hemosiderosis. CONCLUSION Depressed VEGF and increased ferritin in BALF may reflect the severity of chronic pulmonary inflammation in altered respiratory epithelium of childhood ILD.
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Affiliation(s)
- Ágnes Papp
- Department of Pediatrics, Clinical Center, University of Debrecen, Debrecen, Hungary
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Quinn RA, Whiteson K, Lim YW, Salamon P, Bailey B, Mienardi S, Sanchez SE, Blake D, Conrad D, Rohwer F. A Winogradsky-based culture system shows an association between microbial fermentation and cystic fibrosis exacerbation. THE ISME JOURNAL 2015; 9:1024-38. [PMID: 25514533 PMCID: PMC4817692 DOI: 10.1038/ismej.2014.234] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2014] [Revised: 10/24/2014] [Accepted: 11/04/2014] [Indexed: 01/09/2023]
Abstract
There is a poor understanding of how the physiology of polymicrobial communities in cystic fibrosis (CF) lungs contributes to pulmonary exacerbations and lung function decline. In this study, a microbial culture system based on the principles of the Winogradsky column (WinCF system) was developed to study the physiology of CF microbes. The system used glass capillary tubes filled with artificial sputum medium to mimic a clogged airway bronchiole. Chemical indicators were added to observe microbial physiology within the tubes. Characterization of sputum samples from seven patients showed variation in pH, respiration, biofilm formation and gas production, indicating that the physiology of CF microbial communities varied among patients. Incubation of homogenized tissues from an explant CF lung mirrored responses of a Pseudomonas aeruginosa pure culture, supporting evidence that end-stage lungs are dominated by this pathogen. Longitudinal sputum samples taken through two exacerbation events in a single patient showed that a two-unit drop in pH and a 30% increase in gas production occurred in the tubes prior to exacerbation, which was reversed with antibiotic treatment. Microbial community profiles obtained through amplification and sequencing of the 16S rRNA gene showed that fermentative anaerobes became more abundant during exacerbation and were then reduced during treatment where P. aeruginosa became the dominant bacterium. Results from the WinCF experiments support the model where two functionally different CF microbial communities exist, the persistent Climax Community and the acute Attack Community. Fermentative anaerobes are hypothesized to be the core members of the Attack Community and production of acidic and gaseous products from fermentation may drive developing exacerbations. Treatment targeting the Attack Community may better resolve exacerbations and resulting lung damage.
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Affiliation(s)
- Robert A Quinn
- Department of Biology, San Diego State University, San Diego, CA, USA
| | - Katrine Whiteson
- Department of Biology, San Diego State University, San Diego, CA, USA
| | - Yan-Wei Lim
- Department of Biology, San Diego State University, San Diego, CA, USA
| | - Peter Salamon
- Department of Mathematics and Statistics, San Diego State University, San Diego, CA, USA
| | - Barbara Bailey
- Department of Mathematics and Statistics, San Diego State University, San Diego, CA, USA
| | - Simone Mienardi
- Department of Chemistry, University of California, Irvine, CA, USA
| | | | - Don Blake
- Department of Chemistry, University of California, Irvine, CA, USA
| | - Doug Conrad
- Department of Medicine, University of California, San Diego, CA, USA
| | - Forest Rohwer
- Department of Biology, San Diego State University, San Diego, CA, USA
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Tyrrell J, Whelan N, Wright C, Sá-Correia I, McClean S, Thomas M, Callaghan M. Investigation of the multifaceted iron acquisition strategies of Burkholderia cenocepacia. Biometals 2015; 28:367-80. [DOI: 10.1007/s10534-015-9840-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2014] [Accepted: 02/18/2015] [Indexed: 10/23/2022]
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Chillappagari S, Venkatesan S, Garapati V, Mahavadi P, Munder A, Seubert A, Sarode G, Guenther A, Schmeck BT, Tümmler B, Henke MO. Impaired TLR4 and HIF expression in cystic fibrosis bronchial epithelial cells downregulates hemeoxygenase-1 and alters iron homeostasis in vitro. Am J Physiol Lung Cell Mol Physiol 2014; 307:L791-9. [DOI: 10.1152/ajplung.00167.2014] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Hemeoxygenase-1 (HO-1), an inducible heat shock protein, is upregulated in response to multiple cellular insults via oxidative stress, lipopolysaccharides (LPS), and hypoxia. In this study, we investigated in vitro the role of Toll-like receptor 4 (TLR4), hypoxia-inducible factor 1α (HIF-1α), and iron on HO-1 expression in cystic fibrosis (CF). Immunohistochemical analysis of TLR4, HO-1, ferritin, and HIF-1α were performed on lung sections of CFTR−/− and wild-type mice. CFBE41o- and 16HBE14o- cell lines were employed for in vitro analysis via immunoblotting, immunofluorescence, real-time PCR, luciferase reporter gene analysis, and iron quantification. We observed a reduced TLR4, HIF-1α, HO-1, and ferritin in CFBE41o- cell line and CF mice. Knockdown studies using TLR4-siRNA in 16HBE14o- revealed significant decrease of HO-1, confirming the role of TLR4 in HO-1 downregulation. Inhibition of HO-1 using tin protoporphyrin in 16HBE14o- cells resulted in increased iron levels, suggesting a probable role of HO-1 in iron accumulation. Additionally, sequestration of excess iron using iron chelators resulted in increased hypoxia response element response in CFBE41o- and 16HBE14o-, implicating a role of iron in HIF-1α stabilization and HO-1. To conclude, our in vitro results demonstrate that multiple regulatory factors, such as impaired TLR4 surface expression, increased intracellular iron, and decreased HIF-1α, downregulate HO-1 expression in CFBE41o- cells.
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Affiliation(s)
- Shashi Chillappagari
- Department of Medicine, Pulmonary Critical Care Philipps University, Marburg, Germany
- Institute for Lung Research, Philipps-University, Marburg, Germany
- Universities of Giessen and Marburg Lung Center (UGMLC), Giessen, Germany
- Member of the German Center for Lung Research (DZL)
| | - Shalini Venkatesan
- Department of Internal Medicine, Justus-Liebig-University, Giessen, Germany
- Universities of Giessen and Marburg Lung Center (UGMLC), Giessen, Germany
- Member of the German Center for Lung Research (DZL)
| | - Virajith Garapati
- Department of Medicine, Pulmonary Critical Care Philipps University, Marburg, Germany
- Institute for Lung Research, Philipps-University, Marburg, Germany
- Universities of Giessen and Marburg Lung Center (UGMLC), Giessen, Germany
- Member of the German Center for Lung Research (DZL)
| | - Poornima Mahavadi
- Department of Internal Medicine, Justus-Liebig-University, Giessen, Germany
- Universities of Giessen and Marburg Lung Center (UGMLC), Giessen, Germany
- Member of the German Center for Lung Research (DZL)
| | - Antje Munder
- Clinical Research Group ‘Molecular Pathology of Cystic Fibrosis and Pseudomonas Genomics’, Clinic for Pediatric Pneumology, Allergology and Neonatology, Hannover Medical School, Hannover, Germany
- Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Germany
| | - Andreas Seubert
- Department of Chemistry-Biochemistry, Philipps University, Marburg, Germany
| | - Gaurav Sarode
- Department of Medicine, Pulmonary Critical Care Philipps University, Marburg, Germany
- Universities of Giessen and Marburg Lung Center (UGMLC), Giessen, Germany
| | - Andreas Guenther
- Department of Internal Medicine, Justus-Liebig-University, Giessen, Germany
- Lung Clinic Waldhof-Elgershausen, Greifenstein, Germany
- Universities of Giessen and Marburg Lung Center (UGMLC), Giessen, Germany
- Member of the German Center for Lung Research (DZL)
| | - Bernd T. Schmeck
- Institute for Lung Research, Philipps-University, Marburg, Germany
- Universities of Giessen and Marburg Lung Center (UGMLC), Giessen, Germany
- Member of the German Center for Lung Research (DZL)
| | - Burkhard Tümmler
- Clinical Research Group ‘Molecular Pathology of Cystic Fibrosis and Pseudomonas Genomics’, Clinic for Pediatric Pneumology, Allergology and Neonatology, Hannover Medical School, Hannover, Germany
- Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Germany
| | - Markus O. Henke
- Department of Medicine, Pulmonary Critical Care Philipps University, Marburg, Germany
- Universities of Giessen and Marburg Lung Center (UGMLC), Giessen, Germany
- Member of the German Center for Lung Research (DZL)
- Pneumology, Asklepios Fachkliniken München-Gauting, Germany
- Comprehensive Pneumology Center (CPC), Helmholtz Zentrum, Munich, Germany
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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: 46] [Impact Index Per Article: 4.6] [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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What is hepcidin telling us about the natural history of cystic fibrosis? J Cyst Fibros 2014; 14:155-7. [PMID: 24795218 DOI: 10.1016/j.jcf.2014.03.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2014] [Revised: 03/26/2014] [Accepted: 03/26/2014] [Indexed: 12/25/2022]
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Biogeochemical forces shape the composition and physiology of polymicrobial communities in the cystic fibrosis lung. mBio 2014; 5:e00956-13. [PMID: 24643867 PMCID: PMC3967525 DOI: 10.1128/mbio.00956-13] [Citation(s) in RCA: 89] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The cystic fibrosis (CF) lung contains thick mucus colonized by opportunistic pathogens which adapt to the CF lung environment over decades. The difficulty associated with sampling airways has impeded a thorough examination of the biochemical microhabitats these pathogens are exposed to. An indirect approach is to study the responses of microbial communities to these microhabitats, facilitated by high-throughput sequencing of microbial DNA and RNA from sputum samples. Microbial metagenomes and metatranscriptomes were sequenced from multiple CF patients, and the reads were assigned taxonomy and function through sequence homology to NCBI and the Kyoto Encyclopedia of Genes and Genomes (KEGG) database hierarchies. For a comparison, saliva microbial metagenomes from the Human Microbiome Project (HMP) were also analyzed. These analyses identified that functions encoded and expressed by CF microbes were significantly enriched for amino acid catabolism, folate biosynthesis, and lipoic acid biosynthesis. The data indicate that the community uses oxidative phosphorylation as a major energy source but that terminal electron acceptors were diverse. Nitrate reduction was the most abundant anaerobic respiratory pathway, and genes for nitrate reductase were largely assigned to Pseudomonas and Rothia. Although many reductive pathways of the nitrogen cycle were present, the cycle was incomplete, because the oxidative pathways were absent. Due to the abundant amino acid catabolism and incomplete nitrogen cycle, the CF microbial community appears to accumulate ammonia. This finding was verified experimentally using a CF bronchiole culture model system. The data also revealed abundant sensing and transport of iron, ammonium, zinc, and other metals along with a low-oxygen environment. This study reveals the core biochemistry and physiology of the CF microbiome. The cystic fibrosis (CF) microbial community is complex and adapts to the environmental conditions of the lung over the lifetime of a CF patient. This analysis illustrates the core functions of the CF microbial community in the context of CF lung biochemistry. There are many studies of the metabolism and physiology of individual microbes within the CF lung, but none that collectively analyze data from the whole microbiome. Understanding the core metabolism of microbes that inhabit the CF lung can provide new targets for novel therapies. The fundamental processes that CF pathogens rely on for survival may represent an Achilles heel for this pathogenic community. Novel therapies that are designed to disrupt understudied survival strategies of the CF microbial community may succeed against otherwise untreatable or antibiotic-resistant microbes.
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Abstract
Particle exposures increase the risk for human infections. Particles can deposit in the nose, pharynx, larynx, trachea, bronchi, and distal lung and, accordingly, the respiratory tract is the system most frequently infected after such exposure; however, meningitis also occurs. Cigarette smoking, burning of biomass, dust storms, mining, agricultural work, environmental tobacco smoke (ETS), wood stoves, traffic-related emissions, gas stoves, and ambient air pollution are all particle-related exposures associated with an increased risk for respiratory infections. In addition, cigarette smoking, burning of biomass, dust storms, mining, and ETS can result in an elevated risk for tuberculosis, atypical mycobacterial infections, and meningitis. One of the mechanisms for particle-related infections includes an accumulation of iron by surface functional groups of particulate matter (PM). Since elevations in metal availability are common to every particle exposure, all PM potentially contributes to these infections. Therefore, exposures to wood stove emissions, diesel exhaust, and air pollution particles are predicted to increase the incidence and prevalence of tuberculosis, atypical mycobacterial infections, and meningitis, albeit these elevations are likely to be small and detectable only in large population studies. Since iron accumulation correlates with the presence of surface functional groups and dependent metal coordination by the PM, the risk for infection continues as long as the particle is retained. Subsequently, it is expected that the cessation of exposure will diminish, but not totally reverse, the elevated risk for infection.
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Affiliation(s)
- A J Ghio
- National Health and Environmental Effects Research Laboratory, US EPA, Research Triangle Park, NC, 27711, USA,
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Breath gas metabolites and bacterial metagenomes from cystic fibrosis airways indicate active pH neutral 2,3-butanedione fermentation. ISME JOURNAL 2014; 8:1247-58. [PMID: 24401860 PMCID: PMC4030226 DOI: 10.1038/ismej.2013.229] [Citation(s) in RCA: 97] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/05/2013] [Revised: 11/14/2013] [Accepted: 11/15/2013] [Indexed: 12/20/2022]
Abstract
The airways of cystic fibrosis (CF) patients are chronically colonized by patient-specific polymicrobial communities. The conditions and nutrients available in CF lungs affect the physiology and composition of the colonizing microbes. Recent work in bioreactors has shown that the fermentation product 2,3-butanediol mediates cross-feeding between some fermenting bacteria and Pseudomonas aeruginosa, and that this mechanism increases bacterial current production. To examine bacterial fermentation in the respiratory tract, breath gas metabolites were measured and several metagenomes were sequenced from CF and non-CF volunteers. 2,3-butanedione was produced in nearly all respiratory tracts. Elevated levels in one patient decreased during antibiotic treatment, and breath concentrations varied between CF patients at the same time point. Some patients had high enough levels of 2,3-butanedione to irreversibly damage lung tissue. Antibiotic therapy likely dictates the activities of 2,3-butanedione-producing microbes, which suggests a need for further study with larger sample size. Sputum microbiomes were dominated by P. aeruginosa, Streptococcus spp. and Rothia mucilaginosa, and revealed the potential for 2,3-butanedione biosynthesis. Genes encoding 2,3-butanedione biosynthesis were disproportionately abundant in Streptococcus spp, whereas genes for consumption of butanedione pathway products were encoded by P. aeruginosa and R. mucilaginosa. We propose a model where low oxygen conditions in CF lung lead to fermentation and a decrease in pH, triggering 2,3-butanedione fermentation to avoid lethal acidification. We hypothesize that this may also increase phenazine production by P. aeruginosa, increasing reactive oxygen species and providing additional electron acceptors to CF microbes.
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Abstract
Chronic, biofilm-like infections by the opportunistic pathogen Pseudomonas aeruginosa are a major cause of mortality in cystic fibrosis (CF) patients. While much is known about P. aeruginosa from laboratory studies, far less is understood about what it experiences in vivo. Iron is an important environmental parameter thought to play a central role in the development and maintenance of P. aeruginosa infections, for both anabolic and signaling purposes. Previous studies have focused on ferric iron [Fe(III)] as a target for antimicrobial therapies; however, here we show that ferrous iron [Fe(II)] is abundant in the CF lung (~39 µM on average for severely sick patients) and significantly correlates with disease severity (ρ = −0.56, P = 0.004), whereas ferric iron does not (ρ = −0.28, P = 0.179). Expression of the P. aeruginosa genes bqsRS, whose transcription is upregulated in response to Fe(II), was high in the majority of patients tested, suggesting that increased Fe(II) is bioavailable to the infectious bacterial population. Because limiting Fe(III) acquisition inhibits biofilm formation by P. aeruginosa in various oxic in vitro systems, we also tested whether interfering with Fe(II) acquisition would improve biofilm control under anoxic conditions; concurrent sequestration of both iron oxidation states resulted in a 58% reduction in biofilm accumulation and 28% increase in biofilm dissolution, a significant improvement over Fe(III) chelation treatment alone. This study demonstrates that the chemistry of infected host environments coevolves with the microbial community as infections progress, which should be considered in the design of effective treatment strategies at different stages of disease. Iron is an important environmental parameter that helps pathogens thrive in sites of infection, including those of cystic fibrosis (CF) patients. Ferric iron chelation therapy has been proposed as a novel therapeutic strategy for CF lung infections, yet until now, the iron oxidation state has not been measured in the host. In studying mucus from the infected lungs of multiple CF patients from Europe and the United States, we found that ferric and ferrous iron change in concentration and relative proportion as infections progress; over time, ferrous iron comes to dominate the iron pool. This information is relevant to the design of novel CF therapeutics and, more broadly, to developing accurate models of chronic CF infections.
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