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Meng B, Zhao N, Mlcochova P, Ferreira IATM, Ortmann BM, Davis T, Wit N, Rehwinkel J, Cook S, Maxwell PH, Nathan JA, Gupta RK. Hypoxia drives HIF2-dependent reversible macrophage cell cycle entry. Cell Rep 2024; 43:114471. [PMID: 38996069 DOI: 10.1016/j.celrep.2024.114471] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2024] [Revised: 05/22/2024] [Accepted: 06/24/2024] [Indexed: 07/14/2024] Open
Abstract
Low-oxygen conditions (hypoxia) have been associated primarily with cell-cycle arrest in dividing cells. Macrophages are typically quiescent in G0 but can proliferate in response to tissue signals. Here we show that hypoxia (1% oxygen tension) results in reversible entry into the cell cycle in macrophages. Cell cycle progression is largely limited to G0-G1/S phase transition with little progression to G2/M. This cell cycle transitioning is triggered by an HIF2α-directed transcriptional program. The response is accompanied by increased expression of cell-cycle-associated proteins, including CDK1, which is known to phosphorylate SAMHD1 at T592 and thereby regulate antiviral activity. Prolyl hydroxylase (PHD) inhibitors are able to recapitulate HIF2α-dependent cell cycle entry in macrophages. Finally, tumor-associated macrophages (TAMs) in lung cancers exhibit transcriptomic profiles representing responses to low oxygen and cell cycle progression at the single-cell level. These findings have implications for inflammation and tumor progression/metastasis where low-oxygen environments are common.
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Affiliation(s)
- Bo Meng
- Cambridge Institute of Therapeutic Immunology and Infectious Disease (CITIID), Cambridge, UK; Department of Medicine, University of Cambridge, Cambridge, UK.
| | - Na Zhao
- University of Oxford, Oxford, UK
| | - Petra Mlcochova
- Cambridge Institute of Therapeutic Immunology and Infectious Disease (CITIID), Cambridge, UK; Department of Medicine, University of Cambridge, Cambridge, UK
| | - Isabella A T M Ferreira
- Cambridge Institute of Therapeutic Immunology and Infectious Disease (CITIID), Cambridge, UK; Department of Medicine, University of Cambridge, Cambridge, UK
| | - Brian M Ortmann
- Cambridge Institute of Therapeutic Immunology and Infectious Disease (CITIID), Cambridge, UK; Department of Medicine, University of Cambridge, Cambridge, UK
| | | | - Niek Wit
- Cambridge Institute of Therapeutic Immunology and Infectious Disease (CITIID), Cambridge, UK; Department of Medicine, University of Cambridge, Cambridge, UK
| | | | | | | | - James A Nathan
- Cambridge Institute of Therapeutic Immunology and Infectious Disease (CITIID), Cambridge, UK; Department of Medicine, University of Cambridge, Cambridge, UK
| | - Ravindra K Gupta
- Cambridge Institute of Therapeutic Immunology and Infectious Disease (CITIID), Cambridge, UK; Department of Medicine, University of Cambridge, Cambridge, UK; Africa Health Research Institute, Durban, KwaZulu Natal, South Africa.
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2
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Gonzalez OA, Kirakodu S, Nguyen L, Ebersole JL. Macrophage-related gingival transcriptomic patterns and microbiome alterations in experimental periodontitis in nonhuman primates. J Periodontal Res 2023; 58:1148-1170. [PMID: 37610132 DOI: 10.1111/jre.13156] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Revised: 04/05/2023] [Accepted: 06/08/2023] [Indexed: 08/24/2023]
Abstract
OBJECTIVE This study examined the microbiome features specifically related to host macrophage polarization in health, initiation and progression of periodontitis, and in resolution samples using a nonhuman primate model of ligature-induced periodontitis. BACKGROUND The oral microbiome is a complex of bacterial phyla, genera, and species acquired early in life into the individual autochthonous oral ecology. The microbiome changes overtime in response to both intrinsic and extrinsic stressors, and transitions to a dysbiotic ecology at sites of periodontal lesions. METHODS Comparisons were made between the microbial and host features in young (≤7 years) and adult (≥12 years) cohorts of animals. Footprints of macrophage-related genes in the gingival tissues were evaluated using expression profiles including M0, M1, and M2 related genes. RESULTS Within the gingival tissues, similar macrophage-related gene patterns were observed with significant increases with disease initiation and continued elevation throughout disease in both age groups. Approximately, 70% of the taxa were similar in relative abundance between the two groups; however, the adults showed a large number of OTUs that were significantly altered compared with the younger animals. Developing a correlation map identified three major node levels of interactions that comprised approximately ⅓ of the Operational Taxonomic Units (OTUs) that dominated the microbiomes across the samples. Also noted was a much greater frequency of significant correlations of individual OTUs with the macrophage phenotype markers, compared with disease and resolution samples in both age groups, with a greater frequency in the younger group. Moreover, these correlations were assigned to differentially expressed genes representing M0, M1, and M2-related phenotypes. A cluster analyses across the macrophage-related transcriptome and the OTUs demonstrated multiple somewhat distinct bacterial consortia, incorporating both commensal and putative pathogens, linked to the gene responses that differed in health, disease, and resolution samples. Finally, there were minimal alterations in the OTUs in individual clusters with specific macrophage-related responses in the younger group, while in the adult samples substantial variations were noted with genes from all macrophage phenotypes. CONCLUSIONS The results confirmed important features that could reflect macrophage polarization in periodontal lesions, and provided some initial data supporting specific members of the oral microbiome feature prominently related to specific gene response patterns consistent with macrophages in the gingival tissues.
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Affiliation(s)
- O A Gonzalez
- Center for Oral Health Research, College of Dentistry, University of Kentucky, Lexington, Kentucky, USA
- Division of Periodontology, College of Dentistry, University of Kentucky, Lexington, Kentucky, USA
| | - S Kirakodu
- Center for Oral Health Research, College of Dentistry, University of Kentucky, Lexington, Kentucky, USA
| | - L Nguyen
- Department of Biomedical Sciences, School of Dental Medicine, University of Nevada Las Vegas, Las Vegas, Nevada, USA
| | - J L Ebersole
- Department of Biomedical Sciences, School of Dental Medicine, University of Nevada Las Vegas, Las Vegas, Nevada, USA
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Fernández-Billón M, Llambías-Cabot AE, Jordana-Lluch E, Oliver A, Macià MD. Mechanisms of antibiotic resistance in Pseudomonas aeruginosa biofilms. Biofilm 2023; 5:100129. [PMID: 37205903 PMCID: PMC10189392 DOI: 10.1016/j.bioflm.2023.100129] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Revised: 04/29/2023] [Accepted: 05/02/2023] [Indexed: 05/21/2023] Open
Abstract
Pseudomonas aeruginosa is a major cause of life-threatening acute infections and life-long lasting chronic infections. The characteristic biofilm mode of life in P. aeruginosa chronic infections severely limits the efficacy of antimicrobial therapies, as it leads to intrinsic tolerance, involving physical and physiological factors in addition to biofilm-specific genes that can confer a transient protection against antibiotics promoting the development of resistance. Indeed, a striking feature of this pathogen is the extraordinary capacity to develop resistance to nearly all available antibiotics through the selection of chromosomal mutations, evidenced by its outstanding and versatile mutational resistome. This threat is dramatically amplified in chronic infections, driven by the frequent emergence of mutator variants with enhanced spontaneous mutation rates. Thus, this mini review is focused on describing the complex interplay of antibiotic resistance mechanisms in P. aeruginosa biofilms, to provide potentially useful information for the design of effective therapeutic strategies.
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Affiliation(s)
- María Fernández-Billón
- Department of Microbiology, Hospital Universitario Son Espases, Health Research Institute of the Balearic Islands (IdISBa), 07120, Palma de Mallorca, Spain
- Centro de Investigación Biomédica en Red en Enfermedades Infecciosas, Instituto de Salud Carlos III (CIBERINFEC), 28029, Madrid, Spain
| | - Aina E. Llambías-Cabot
- Department of Microbiology, Hospital Universitario Son Espases, Health Research Institute of the Balearic Islands (IdISBa), 07120, Palma de Mallorca, Spain
- Centro de Investigación Biomédica en Red en Enfermedades Infecciosas, Instituto de Salud Carlos III (CIBERINFEC), 28029, Madrid, Spain
| | - Elena Jordana-Lluch
- Department of Microbiology, Hospital Universitario Son Espases, Health Research Institute of the Balearic Islands (IdISBa), 07120, Palma de Mallorca, Spain
- Centro de Investigación Biomédica en Red en Enfermedades Infecciosas, Instituto de Salud Carlos III (CIBERINFEC), 28029, Madrid, Spain
| | - Antonio Oliver
- Department of Microbiology, Hospital Universitario Son Espases, Health Research Institute of the Balearic Islands (IdISBa), 07120, Palma de Mallorca, Spain
- Centro de Investigación Biomédica en Red en Enfermedades Infecciosas, Instituto de Salud Carlos III (CIBERINFEC), 28029, Madrid, Spain
| | - María D. Macià
- Department of Microbiology, Hospital Universitario Son Espases, Health Research Institute of the Balearic Islands (IdISBa), 07120, Palma de Mallorca, Spain
- Centro de Investigación Biomédica en Red en Enfermedades Infecciosas, Instituto de Salud Carlos III (CIBERINFEC), 28029, Madrid, Spain
- Corresponding author. Department of Microbiology, Hospital Universitario Son Espases, Crta. Vallemossa 79, 07120, Palma de Mallorca, Spain.
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DeMichele E, Sosnowski O, Buret AG, Allain T. Regulatory Functions of Hypoxia in Host-Parasite Interactions: A Focus on Enteric, Tissue, and Blood Protozoa. Microorganisms 2023; 11:1598. [PMID: 37375100 PMCID: PMC10303274 DOI: 10.3390/microorganisms11061598] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Revised: 06/13/2023] [Accepted: 06/14/2023] [Indexed: 06/29/2023] Open
Abstract
Body tissues are subjected to various oxygenic gradients and fluctuations and hence can become transiently hypoxic. Hypoxia-inducible factor (HIF) is the master transcriptional regulator of the cellular hypoxic response and is capable of modulating cellular metabolism, immune responses, epithelial barrier integrity, and local microbiota. Recent reports have characterized the hypoxic response to various infections. However, little is known about the role of HIF activation in the context of protozoan parasitic infections. Growing evidence suggests that tissue and blood protozoa can activate HIF and subsequent HIF target genes in the host, helping or hindering their pathogenicity. In the gut, enteric protozoa are adapted to steep longitudinal and radial oxygen gradients to complete their life cycle, yet the role of HIF during these protozoan infections remains unclear. This review focuses on the hypoxic response to protozoa and its role in the pathophysiology of parasitic infections. We also discuss how hypoxia modulates host immune responses in the context of protozoan infections.
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Affiliation(s)
- Emily DeMichele
- Department of Biological Sciences, University of Calgary, Calgary, AB T2N 1N4, Canada; (E.D.); (O.S.); (A.G.B.)
- Inflammation Research Network, University of Calgary, Calgary, AB T2N 1N4, Canada
- Host-Parasite Interactions, University of Calgary, Calgary, AB T2N 1N4, Canada
| | - Olivia Sosnowski
- Department of Biological Sciences, University of Calgary, Calgary, AB T2N 1N4, Canada; (E.D.); (O.S.); (A.G.B.)
- Inflammation Research Network, University of Calgary, Calgary, AB T2N 1N4, Canada
- Host-Parasite Interactions, University of Calgary, Calgary, AB T2N 1N4, Canada
| | - Andre G. Buret
- Department of Biological Sciences, University of Calgary, Calgary, AB T2N 1N4, Canada; (E.D.); (O.S.); (A.G.B.)
- Inflammation Research Network, University of Calgary, Calgary, AB T2N 1N4, Canada
- Host-Parasite Interactions, University of Calgary, Calgary, AB T2N 1N4, Canada
| | - Thibault Allain
- Department of Biological Sciences, University of Calgary, Calgary, AB T2N 1N4, Canada; (E.D.); (O.S.); (A.G.B.)
- Inflammation Research Network, University of Calgary, Calgary, AB T2N 1N4, Canada
- Host-Parasite Interactions, University of Calgary, Calgary, AB T2N 1N4, Canada
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5
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Moore-Machacek A, Gloe A, O'Leary N, Reen FJ. Efflux, Signaling and Warfare in a Polymicrobial World. Antibiotics (Basel) 2023; 12:antibiotics12040731. [PMID: 37107093 PMCID: PMC10135244 DOI: 10.3390/antibiotics12040731] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Revised: 03/30/2023] [Accepted: 04/04/2023] [Indexed: 04/29/2023] Open
Abstract
The discovery void of antimicrobial development has occurred at a time when the world has seen a rapid emergence and spread of antimicrobial resistance, the 'perfect storm' as it has often been described. While the discovery and development of new antibiotics has continued in the research sphere, the pipeline to clinic has largely been fed by derivatives of existing classes of antibiotics, each prone to pre-existing resistance mechanisms. A novel approach to infection management has come from the ecological perspective whereby microbial networks and evolved communities already possess small molecular capabilities for pathogen control. The spatiotemporal nature of microbial interactions is such that mutualism and parasitism are often two ends of the same stick. Small molecule efflux inhibitors can directly target antibiotic efflux, a primary resistance mechanism adopted by many species of bacteria and fungi. However, a much broader anti-infective capability resides within the action of these inhibitors, borne from the role of efflux in key physiological and virulence processes, including biofilm formation, toxin efflux, and stress management. Understanding how these behaviors manifest within complex polymicrobial communities is key to unlocking the full potential of the advanced repertoires of efflux inhibitors.
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Affiliation(s)
| | - Antje Gloe
- School of Microbiology, University College Cork, T12 K8AF Cork, Ireland
- Institute for Pharmaceutical Microbiology, University of Bonn, D-53113 Bonn, Germany
| | - Niall O'Leary
- School of Microbiology, University College Cork, T12 K8AF Cork, Ireland
| | - F Jerry Reen
- School of Microbiology, University College Cork, T12 K8AF Cork, Ireland
- Synthesis and Solid-State Pharmaceutical Centre, University College Cork, T12 K8AF Cork, Ireland
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Cartwright IM, Colgan SP. The hypoxic tissue microenvironment as a driver of mucosal inflammatory resolution. Front Immunol 2023; 14:1124774. [PMID: 36742292 PMCID: PMC9890178 DOI: 10.3389/fimmu.2023.1124774] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Accepted: 01/06/2023] [Indexed: 01/19/2023] Open
Abstract
On the backdrop of all acute inflammatory processes lies the activation of the resolution response. Recent years have witnessed an emerging interest in defining molecular factors that influence the resolution of inflammation. A keystone feature of the mucosal inflammatory microenvironment is hypoxia. The gastrointestinal tract, particularly the colon, exists in a state of physiological hypoxia and during active inflammation, this hypoxic state is enhanced as a result of infiltrating leukocyte oxygen consumption and the activation of oxygen consuming enzymes. Most evidence suggests that mucosal hypoxia promotes the active resolution of inflammation through a variety of mechanisms, including extracellular acidification, purine biosynthesis/salvage, the generation of specialized pro-resolving lipid mediators (ie. resolvins) and altered chemokine/cytokine expression. It is now appreciated that infiltrating innate immune cells (neutrophils, eosinophils, macrophages) have an important role in molding the tissue microenvironment to program an active resolution response. Structural or functional dysregulation of this inflammatory microenvironment can result in the loss of tissue homeostasis and ultimately progression toward chronicity. In this review, we will discuss how inflammatory hypoxia drives mucosal inflammatory resolution and its impact on other microenvironmental factors that influence resolution.
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Affiliation(s)
- Ian M. Cartwright
- Division of Gastroenterology and Hepatology, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
- Department of Medicine, University of Colorado School of Medicine, Aurora, CO, United States
- Mucosal Inflammation Program, University of Colorado School of Medicine, Aurora, CO, United States
- Rocky Mountain Regional Veterans Affairs Medical Center, Aurora, CO, United States
| | - Sean P. Colgan
- Division of Gastroenterology and Hepatology, University of Colorado Anschutz Medical Campus, Aurora, CO, United States
- Department of Medicine, University of Colorado School of Medicine, Aurora, CO, United States
- Mucosal Inflammation Program, University of Colorado School of Medicine, Aurora, CO, United States
- Rocky Mountain Regional Veterans Affairs Medical Center, Aurora, CO, United States
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7
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Woods PS, Kimmig LM, Sun KA, Meliton AY, Shamaa OR, Tian Y, Cetin-Atalay R, Sharp WW, Hamanaka RB, Mutlu GM. HIF-1α induces glycolytic reprograming in tissue-resident alveolar macrophages to promote cell survival during acute lung injury. eLife 2022; 11:e77457. [PMID: 35822617 PMCID: PMC9323005 DOI: 10.7554/elife.77457] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Accepted: 07/10/2022] [Indexed: 12/03/2022] Open
Abstract
Cellular metabolism is a critical regulator of macrophage effector function. Tissue-resident alveolar macrophages (TR-AMs) inhabit a unique niche marked by high oxygen and low glucose. We have recently shown that in contrast to bone marrow-derived macrophages (BMDMs), TR-AMs do not utilize glycolysis and instead predominantly rely on mitochondrial function for their effector response. It is not known how changes in local oxygen concentration that occur during conditions such as acute respiratory distress syndrome (ARDS) might affect TR-AM metabolism and function; however, ARDS is associated with progressive loss of TR-AMs, which correlates with the severity of disease and mortality. Here, we demonstrate that hypoxia robustly stabilizes HIF-1α in TR-AMs to promote a glycolytic phenotype. Hypoxia altered TR-AM metabolite signatures, cytokine production, and decreased their sensitivity to the inhibition of mitochondrial function. By contrast, hypoxia had minimal effects on BMDM metabolism. The effects of hypoxia on TR-AMs were mimicked by FG-4592, a HIF-1α stabilizer. Treatment with FG-4592 decreased TR-AM death and attenuated acute lung injury in mice. These findings reveal the importance of microenvironment in determining macrophage metabolic phenotype and highlight the therapeutic potential in targeting cellular metabolism to improve outcomes in diseases characterized by acute inflammation.
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Affiliation(s)
- Parker S Woods
- Department of Medicine, Section of Pulmonary and Critical Care Medicine, The University of ChicagoChicagoUnited States
| | - Lucas M Kimmig
- Department of Medicine, Section of Pulmonary and Critical Care Medicine, The University of ChicagoChicagoUnited States
| | - Kaitlyn A Sun
- Department of Medicine, Section of Pulmonary and Critical Care Medicine, The University of ChicagoChicagoUnited States
| | - Angelo Y Meliton
- Department of Medicine, Section of Pulmonary and Critical Care Medicine, The University of ChicagoChicagoUnited States
| | - Obada R Shamaa
- Department of Medicine, Section of Pulmonary and Critical Care Medicine, The University of ChicagoChicagoUnited States
| | - Yufeng Tian
- Department of Medicine, Section of Pulmonary and Critical Care Medicine, The University of ChicagoChicagoUnited States
| | - Rengül Cetin-Atalay
- Department of Medicine, Section of Pulmonary and Critical Care Medicine, The University of ChicagoChicagoUnited States
| | - Willard W Sharp
- Department of Medicine, Section of Emergency Medicine, The University of ChicagoChicagoUnited States
| | - Robert B Hamanaka
- Department of Medicine, Section of Pulmonary and Critical Care Medicine, The University of ChicagoChicagoUnited States
| | - Gökhan M Mutlu
- Department of Medicine, Section of Pulmonary and Critical Care Medicine, The University of ChicagoChicagoUnited States
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8
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Margaroli C, Horati H, Garratt LW, Giacalone VD, Schofield C, Dittrich AS, Rosenow T, Dobosh BS, Lim HS, Frey DL, Veltman M, Silva GL, Brown MR, Schultz C, Tiddens HAWM, Ranganathan S, Chandler JD, Qiu P, Peng L, Scholte BJ, Mall MA, Kicic A, Guglani L, Stick SM, Janssens HM, Tirouvanziam R. Macrophage PD-1 associates with neutrophilia and reduced bacterial killing in early cystic fibrosis airway disease. J Cyst Fibros 2022; 21:967-976. [PMID: 35732550 DOI: 10.1016/j.jcf.2022.06.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Revised: 05/17/2022] [Accepted: 06/02/2022] [Indexed: 10/17/2022]
Abstract
BACKGROUND Macrophages are the major resident immune cells in human airways coordinating responses to infection and injury. In cystic fibrosis (CF), neutrophils are recruited to the airways shortly after birth, and actively exocytose damaging enzymes prior to chronic infection, suggesting a potential defect in macrophage immunomodulatory function. Signaling through the exhaustion marker programmed death protein 1 (PD-1) controls macrophage function in cancer, sepsis, and airway infection. Therefore, we sought to identify potential associations between macrophage PD-1 and markers of airway disease in children with CF. METHODS Blood and bronchoalveolar lavage fluid (BALF) were collected from 45 children with CF aged 3 to 62 months and structural lung damage was quantified by computed tomography. The phenotype of airway leukocytes was assessed by flow cytometry, while the release of enzymes and immunomodulatory mediators by molecular assays. RESULTS Airway macrophage PD-1 expression correlated positively with structural lung damage, neutrophilic inflammation, and infection. Interestingly, even in the absence of detectable infection, macrophage PD-1 expression was elevated and correlated with neutrophilic inflammation. In an in vitro model mimicking leukocyte recruitment into CF airways, soluble mediators derived from recruited neutrophils directly induced PD-1 expression on recruited monocytes/macrophages, suggesting a causal link between neutrophilic inflammation and macrophage PD-1 expression in CF. Finally, blockade of PD-1 in a short-term culture of CF BALF leukocytes resulted in improved pathogen clearance. CONCLUSION Taken together, these findings suggest that in early CF lung disease, PD-1 upregulation associates with airway macrophage exhaustion, neutrophil takeover, infection, and structural damage.
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Affiliation(s)
- Camilla Margaroli
- Department of Pediatrics, Center for CF & Airways Disease Research, Children's Healthcare of Atlanta, IMPEDE-CF Program, Emory University School of Medicine, Atlanta, GA, United States of America
| | - Hamed Horati
- Department of Pediatrics, Div. of Respiratory Medicine and Allergology, I-BALL program, Erasmus MC-Sophia Children's Hospital, University Hospital Rotterdam, Rotterdam, The Netherlands
| | - Luke W Garratt
- AREST-CF Program, Telethon Kids Institute, University of Western Australia, Perth, Australia
| | - Vincent D Giacalone
- Department of Pediatrics, Center for CF & Airways Disease Research, Children's Healthcare of Atlanta, IMPEDE-CF Program, Emory University School of Medicine, Atlanta, GA, United States of America
| | - Craig Schofield
- AREST-CF Program, Telethon Kids Institute, University of Western Australia, Perth, Australia
| | - A Susanne Dittrich
- Department of Translational Pulmonology, Translational Lung Research Center (TLRC), German Center for Lung Research (DZL) and Department of Pulmonology, and Critical Care Medicine, Thoraxklinik at the University of Heidelberg, Heidelberg, Germany
| | - Tim Rosenow
- AREST-CF Program, Telethon Kids Institute, University of Western Australia, Perth, Australia
| | - Brian S Dobosh
- Department of Pediatrics, Center for CF & Airways Disease Research, Children's Healthcare of Atlanta, IMPEDE-CF Program, Emory University School of Medicine, Atlanta, GA, United States of America
| | - Hong S Lim
- Department of Biomedical engineering, The Georgia Institute of Technology and Emory University, Atlanta, GA, United States of America
| | - Dario L Frey
- Department of Translational Pulmonology, Translational Lung Research Center (TLRC), German Center for Lung Research (DZL) and Department of Pulmonology, and Critical Care Medicine, Thoraxklinik at the University of Heidelberg, Heidelberg, Germany
| | - Mieke Veltman
- Department of Pediatrics, Div. of Respiratory Medicine and Allergology, I-BALL program, Erasmus MC-Sophia Children's Hospital, University Hospital Rotterdam, Rotterdam, The Netherlands
| | - George L Silva
- Department of Pediatrics, Center for CF & Airways Disease Research, Children's Healthcare of Atlanta, IMPEDE-CF Program, Emory University School of Medicine, Atlanta, GA, United States of America
| | - Milton R Brown
- Department of Pediatrics, Center for CF & Airways Disease Research, Children's Healthcare of Atlanta, IMPEDE-CF Program, Emory University School of Medicine, Atlanta, GA, United States of America
| | - Carsten Schultz
- Department of Physiology and Pharmacology, Oregon Health & Science University, Portland, OR, United States of America
| | - Harm A W M Tiddens
- Department of Pediatrics, Div. of Respiratory Medicine and Allergology, I-BALL program, Erasmus MC-Sophia Children's Hospital, University Hospital Rotterdam, Rotterdam, The Netherlands
| | - Sarath Ranganathan
- Department of Pediatrics, University of Melbourne, Melbourne, Australia; Murdoch Children's Research Institute, and Department of Respiratory and Sleep Medicine, Royal Children's Hospital, Parkville, Australia
| | - Joshua D Chandler
- Department of Pediatrics, Center for CF & Airways Disease Research, Children's Healthcare of Atlanta, IMPEDE-CF Program, Emory University School of Medicine, Atlanta, GA, United States of America
| | - Peng Qiu
- Department of Biomedical engineering, The Georgia Institute of Technology and Emory University, Atlanta, GA, United States of America
| | - Limin Peng
- Department of Pediatrics, Center for CF & Airways Disease Research, Children's Healthcare of Atlanta, IMPEDE-CF Program, Emory University School of Medicine, Atlanta, GA, United States of America; Department of Biostatistics, Emory University School of Public Health, Atlanta, GA, United States of America
| | - Bob J Scholte
- Department of Pediatrics, Div. of Respiratory Medicine and Allergology, I-BALL program, Erasmus MC-Sophia Children's Hospital, University Hospital Rotterdam, Rotterdam, The Netherlands
| | - Marcus A Mall
- Department of Translational Pulmonology, Translational Lung Research Center (TLRC), German Center for Lung Research (DZL) and Department of Pulmonology, and Critical Care Medicine, Thoraxklinik at the University of Heidelberg, Heidelberg, Germany; Department of Pediatric Pulmonology, Immunology and Intensive Care Medicine, Charité - Universitätsmedizin Berlin, and Berlin Institute of Health (BIH), Berlin, Germany
| | - Anthony Kicic
- AREST-CF Program, Telethon Kids Institute, University of Western Australia, Perth, Australia; Department of Respiratory and Sleep Medicine, Perth Children's Hospital and Faculty of Medicine, University of Western Australia, Perth, Western Australia, Australia; School of Public Heath, Curtin University, Perth, Western Australia, Australia
| | - Lokesh Guglani
- Department of Pediatrics, Center for CF & Airways Disease Research, Children's Healthcare of Atlanta, IMPEDE-CF Program, Emory University School of Medicine, Atlanta, GA, United States of America
| | - Stephen M Stick
- AREST-CF Program, Telethon Kids Institute, University of Western Australia, Perth, Australia; Department of Respiratory and Sleep Medicine, Perth Children's Hospital and Faculty of Medicine, University of Western Australia, Perth, Western Australia, Australia
| | - Hettie M Janssens
- Department of Pediatrics, Div. of Respiratory Medicine and Allergology, I-BALL program, Erasmus MC-Sophia Children's Hospital, University Hospital Rotterdam, Rotterdam, The Netherlands
| | - Rabindra Tirouvanziam
- Department of Pediatrics, Center for CF & Airways Disease Research, Children's Healthcare of Atlanta, IMPEDE-CF Program, Emory University School of Medicine, Atlanta, GA, United States of America.
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9
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Felix FB, Vago JP, Beltrami VA, Araújo JMD, Grespan R, Teixeira MM, Pinho V. Biochanin A as a modulator of the inflammatory response: an updated overview and therapeutic potential. Pharmacol Res 2022; 180:106246. [PMID: 35562014 DOI: 10.1016/j.phrs.2022.106246] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Revised: 04/19/2022] [Accepted: 05/03/2022] [Indexed: 12/15/2022]
Abstract
Uncontrolled inflammation and failure to resolve the inflammatory response are crucial factors involved in the progress of inflammatory diseases. Current therapeutic strategies aimed at controlling excessive inflammation are effective in some cases, though they may be accompanied by severe side effects, such as immunosuppression. Phytochemicals as a therapeutic alternative can have a fundamental impact on the different stages of inflammation and its resolution. Biochanin A (BCA) is an isoflavone known for its wide range of pharmacological properties, especially its marked anti-inflammatory effects. Recent studies have provided evidence of BCA's abilities to activate events essential for resolving inflammation. In this review, we summarize the most recent findings from pre-clinical studies of the pharmacological effects of BCA on the complex signaling network associated with the onset and resolution of inflammation and BCA's potential protective functionality in several models of inflammatory diseases, such as arthritis, pulmonary disease, neuroinflammation, and metabolic disease.
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Affiliation(s)
- Franciel Batista Felix
- Department of Morphology, Institute of Biological Sciences, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Juliana Priscila Vago
- Experimental Rheumatology, Department of Rheumatology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Vinícius Amorim Beltrami
- Department of Morphology, Institute of Biological Sciences, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | | | - Renata Grespan
- Cell Migration Laboratory, Department of Physiology, Universidade Federal de Sergipe, São Cristovão, Brazil
| | - Mauro Martins Teixeira
- Department of Biochemistry and Immunology, Institute of Biological Sciences, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Vanessa Pinho
- Department of Morphology, Institute of Biological Sciences, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil.
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Del Mar Cendra M, Torrents E. Differential adaptability between reference strains and clinical isolates of Pseudomonas aeruginosa into the lung epithelium intracellular lifestyle. Virulence 2021; 11:862-876. [PMID: 32697923 PMCID: PMC7549915 DOI: 10.1080/21505594.2020.1787034] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022] Open
Abstract
Intracellular invasion is an advantageous mechanism used by pathogens to evade host defense and antimicrobial therapy. In patients, the intracellular microbial lifestyle can lead to infection persistence and recurrence, thus worsening outcomes. Lung infections caused by Pseudomonas aeruginosa, especially in cystic fibrosis (CF) patients, are often aggravated by intracellular invasion and persistence of the pathogen. Proliferation of the infectious species relies on a continuous deoxyribonucleotide (dNTP) supply, for which the ribonucleotide reductase enzyme (RNR) is the unique provider. The large genome plasticity of P. aeruginosa and its ability to rapidly adapt to different environments are challenges for studying the pathophysiology associated with this type of infection. Using different reference strains and clinical isolates of P. aeruginosa independently combined with alveolar (A549) and bronchial (16HBE14o- and CF-CFBE41o-) epithelial cells, we analyzed host-pathogen interactions and intracellular bacterial persistence with the aim of determining a cell type-directed infection promoted by the P. aeruginosa strains. The oscillations in cellular toxicity and oxygen consumption promoted by the intracellular persistence of the strains were also analyzed among the different infectious lung models. Significantly, we identified class II RNR as the enzyme that supplies dNTPs to intracellular P. aeruginosa. This discovery could contribute to the development of RNR-targeted strategies against the chronicity occurring in this type of lung infection. Overall our study demonstrates that the choice of bacterial strain is critical to properly study the type of infectious process with relevant translational outcomes.
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Affiliation(s)
- Maria Del Mar Cendra
- Bacterial Infections and Antimicrobial Therapies Group, Institute for Bioengineering of Catalonia (IBEC), the Barcelona Institute of Science and Technology , Barcelona, Spain
| | - Eduard Torrents
- Bacterial Infections and Antimicrobial Therapies Group, Institute for Bioengineering of Catalonia (IBEC), the Barcelona Institute of Science and Technology , Barcelona, Spain.,Microbiology Section, Department of Genetics, Microbiology and Statistics, Faculty of Biology, University of Barcelona , Barcelona, Spain
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11
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Oktaria V, Triasih R, Graham SM, Bines JE, Soenarto Y, Clarke MW, Lauda M, Danchin M. Vitamin D deficiency and severity of pneumonia in Indonesian children. PLoS One 2021; 16:e0254488. [PMID: 34242372 PMCID: PMC8270442 DOI: 10.1371/journal.pone.0254488] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Accepted: 06/29/2021] [Indexed: 11/18/2022] Open
Abstract
Objective To determine the prevalence of vitamin D deficiency in Indonesian children hospitalized with pneumonia and evaluate the association between vitamin D status and severity of pneumonia. Methods A hospital-based cross-sectional study was conducted from February 2016 to July 2017 in two district hospitals in Yogyakarta province, Indonesia. Infants and young children aged 2–59 months hospitalized with pneumonia were recruited. Serum blood samples were collected on admission and analyzed for total serum 25-hydroxyvitamin D3 and 25-hydroxyvitamin D2 concentrations using liquid chromatography-tandem mass spectrometry. Vitamin D deficiency was defined as a level of serum vitamin D <50 nmol/L. The association between vitamin D deficiency and severity of hospitalized pneumonia according to WHO criteria, including the presence of danger signs, hypoxemia (SpO2 in air below 90%), duration of hospitalization, and admission to Intensive Care Unit (ICU), was analyzed using logistic regression. Results 133 children with WHO-defined pneumonia were enrolled in the study and 127 (96%) had their vitamin D status determined. The mean vitamin D concentration was 67 (± 24 SD) nmol/L and 19% of participants were vitamin D deficient. Age younger than 6 months was associated with prolonged hospitalization (> 5 days) and low birth weight and poor nutritional status on admission were risk factors for hypoxemia. However, vitamin D status was not associated with the presence of danger signs, duration of hospitalization, or hypoxemia. Conclusions One in every five children hospitalized with pneumonia was vitamin D deficient. Vitamin D status was not associated with the severity of pneumonia.
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Affiliation(s)
- Vicka Oktaria
- Faculty Medicine, Department of Paediatrics, Dentistry and Health Sciences, The University of Melbourne, Melbourne, Australia
- Murdoch Children’s Research Institute, Royal Children’s Hospital, Melbourne, Australia
- Faculty of Medicine, Department of Biostatistics, Epidemiology and Population Health, Public Health and Nursing, Universitas Gadjah Mada, Yogyakarta, Indonesia
- Faculty of Medicine, Center for Child Health–Pediatric Research Office (CCH_PRO), Public Health and Nursing, Universitas Gadjah Mada, Yogyakarta, Indonesia
- * E-mail:
| | - Rina Triasih
- Faculty of Medicine, Center for Child Health–Pediatric Research Office (CCH_PRO), Public Health and Nursing, Universitas Gadjah Mada, Yogyakarta, Indonesia
- Faculty of Medicine, Child Health Department, Public Health, and Nursing, Universitas Gadjah Mada/Dr. Sardjito Hospital, Yogyakarta, Indonesia
| | - Stephen M. Graham
- Faculty Medicine, Department of Paediatrics, Dentistry and Health Sciences, The University of Melbourne, Melbourne, Australia
- Murdoch Children’s Research Institute, Royal Children’s Hospital, Melbourne, Australia
| | - Julie E. Bines
- Faculty Medicine, Department of Paediatrics, Dentistry and Health Sciences, The University of Melbourne, Melbourne, Australia
- Murdoch Children’s Research Institute, Royal Children’s Hospital, Melbourne, Australia
| | - Yati Soenarto
- Faculty of Medicine, Center for Child Health–Pediatric Research Office (CCH_PRO), Public Health and Nursing, Universitas Gadjah Mada, Yogyakarta, Indonesia
- Faculty of Medicine, Child Health Department, Public Health, and Nursing, Universitas Gadjah Mada/Dr. Sardjito Hospital, Yogyakarta, Indonesia
| | - Michael W. Clarke
- Faculty of Health, and Medical Sciences, Metabolomics Australia, Centre for Microscopy, Characterisation, and Analysis, and School of Biomedical Sciences, The University of Western Australia, Perth, WA, Australia
| | - Mike Lauda
- Faculty of Medicine, Child Health Department, Public Health, and Nursing, Universitas Gadjah Mada/Dr. Sardjito Hospital, Yogyakarta, Indonesia
| | - Margaret Danchin
- Faculty Medicine, Department of Paediatrics, Dentistry and Health Sciences, The University of Melbourne, Melbourne, Australia
- Murdoch Children’s Research Institute, Royal Children’s Hospital, Melbourne, Australia
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12
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Ye Y, Chen Y, Sun J, Zhang H, Meng Y, Li W, Wang W. Hyperglycemia suppresses the regulatory effect of hypoxia-inducible factor-1α in pulmonary Aspergillus fumigatus infection. Pathog Dis 2021; 78:5873010. [PMID: 32678442 DOI: 10.1093/femspd/ftaa038] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2020] [Accepted: 07/16/2020] [Indexed: 12/27/2022] Open
Abstract
Aspergillus fumigatus is one of the most common fungal infections involved in the pulmonary diseases. Hypoxia-inducible factor-1α (HIF-1α) is important for antifungal immunity. Diabetes is a risk factor of pulmonary A. fumigatus infection and could affect the expression of HIF-1α. The aim of this investigation was to evaluate the role of HIF-1α in pulmonary A. fumigatus infection in diabetes. In murine model, we found diabetic mice had aggravated pulmonary A. fumigatus infection and declined expression of HIF-1α following pulmonary A. fumigatus infection. And these changes could be corrected by dimethyloxalylglycine (DMOG), the agonist of HIF-1α. In cell experiment, after A. fumigatus stimulation, hyperglycemic state was with a decreased HIF-1α expression and increased NLRP3/IL-1β signal pathway. The percentages of Th1 and Treg cells decreased, while percentages of Th2 and Th17 increased in hyperglycemic group. DMOG suppressed A. fumigatus-stimulated NLRP3 and IL-1β expressions in hyperglycemic group and corrected Th and Treg cells differentiation. These regulatory effects of DMOG could be dampened by activating of NLRP3. These data indicated that hyperglycemia suppressed the regulatory effect of HIF-1α in pulmonary A. fumigatus infection, which can affect Th and Treg cells differentiation by regulating the NLRP3/IL-1β signal pathway.
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Affiliation(s)
- Yao Ye
- Department of Respiratory and Critical Care Medicine, The First Hospital of China Medical University, Shenyang, 110000, China
| | - Yu Chen
- Department of Pulmonary and Critical Care Medicine, Shengjing Hospital of China Medical University, Shenyang, 110000, China
| | - Jianjun Sun
- Department of Respiratory and Critical Care Medicine, The First Hospital of China Medical University, Shenyang, 110000, China
| | - Hanyin Zhang
- Department of Respiratory and Critical Care Medicine, The First Hospital of China Medical University, Shenyang, 110000, China
| | - Yanling Meng
- Department of Respiratory and Critical Care Medicine, The First Hospital of China Medical University, Shenyang, 110000, China
| | - Wenyang Li
- Department of Respiratory and Critical Care Medicine, The First Hospital of China Medical University, Shenyang, 110000, China
| | - Wei Wang
- Department of Respiratory and Critical Care Medicine, The First Hospital of China Medical University, Shenyang, 110000, China
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13
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Gryffin PA, Diaz RE. Effects of Tai Chi and running on blood oxygen saturation: a pilot study. JOURNAL OF COMPLEMENTARY & INTEGRATIVE MEDICINE 2021; 18:821-825. [PMID: 33793144 DOI: 10.1515/jcim-2020-0306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2020] [Accepted: 10/21/2020] [Indexed: 11/15/2022]
Abstract
OBJECTIVES Large drops in blood oxygen saturation (SpO2) to levels as low as 84% was observed following Tai Chi practice, during a study on the effects of Tai Chi on SpO2. The objectives of the current pilot study were to determine if this was a statistically significant drop, and how SpO2 levels compared to an aerobic activity such as running, in pre, concurrent, and post measurements. METHODS Repeated measures of blood oxygen saturation (SpO2) were taken of a 50-year-old male before, during and for 1 min after TC and running. RESULTS Measurements of SpO2 before, during, and after TC resulted in a statistically significant increase in SpO2 during TC (p=1.69e-06), and a statistically significant (p=1.71e-06) brief momentary drop from resting levels, as low as 87% SpO2. Running showed no significant change in pre and post levels, with a significant change and decrease in SpO2 during running (p=1.1e-08), suggesting increased oxygen use by the large muscle groups during exercise. SpO2 returned to normal resting levels following running with no post drop. Results suggest a higher rate of oxygen metabolism during TC, with a potential effect on hypoxic (oxygen deficient) areas of the body. CONCLUSIONS Findings suggest direct and unique effects on enhanced blood oxygen saturation and oxygen metabolism, which may underlie benefits for conditions complicated by hypoxia, including cardiopulmonary disease, immunity, chronic pain, and arthritis.
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Affiliation(s)
| | - Rafael E Diaz
- California State University Sacramento, Sacramento, CA, USA
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14
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Redox Active Antimicrobial Peptides in Controlling Growth of Microorganisms at Body Barriers. Antioxidants (Basel) 2021; 10:antiox10030446. [PMID: 33805777 PMCID: PMC7998263 DOI: 10.3390/antiox10030446] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Revised: 03/05/2021] [Accepted: 03/09/2021] [Indexed: 01/14/2023] Open
Abstract
Epithelia in the skin, gut and other environmentally exposed organs display a variety of mechanisms to control microbial communities and limit potential pathogenic microbial invasion. Naturally occurring antimicrobial proteins/peptides and their synthetic derivatives (here collectively referred to as AMPs) reinforce the antimicrobial barrier function of epithelial cells. Understanding how these AMPs are functionally regulated may be important for new therapeutic approaches to combat microbial infections. Some AMPs are subject to redox-dependent regulation. This review aims to: (i) explore cysteine-based redox active AMPs in skin and intestine; (ii) discuss casual links between various redox environments of these barrier tissues and the ability of AMPs to control cutaneous and intestinal microbes; (iii) highlight how bacteria, through intrinsic mechanisms, can influence the bactericidal potential of redox-sensitive AMPs.
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15
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Gil-Marqués ML, Labrador Herrera G, Miró Canturri A, Pachón J, Smani Y, Pachón-Ibáñez ME. Role of PstS in the Pathogenesis of Acinetobacter baumannii Under Microaerobiosis and Normoxia. J Infect Dis 2021; 222:1204-1212. [PMID: 32324853 DOI: 10.1093/infdis/jiaa201] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Accepted: 04/20/2020] [Indexed: 01/15/2023] Open
Abstract
Acinetobacter baumannii is a successful pathogen responsible for infections with high mortality rate. During the course of infection it can be found in microaerobic environments, which influences virulence factor expression. From a previous transcriptomic analysis of A. baumannii ATCC 17978 under microaerobiosis, we know the gene pstS is overexpressed under microaerobiosis. Here, we studied its role in A. baumannii virulence. pstS loss significantly decreased bacterial adherence and invasion into A549 cells and increased A549 cell viability. pstS loss also reduced motility and biofilm-forming ability of A. baumannii. In a peritoneal sepsis murine model, the minimum lethal dose required by A. baumannii ATCC 17978 ΔpstS was lower compared to the wild type (4.3 vs 3.2 log colony forming units/mL, respectively), and the bacterial burden in tissues and fluids was lower. Thus, the loss of the phosphate sensor PstS produced a decrease in A. baumannii pathogenesis, supporting its role as a virulence factor.
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Affiliation(s)
- María Luisa Gil-Marqués
- Clinical Unit of Infectious Diseases, Microbiology, and Preventive Medicine, Institute of Biomedicine of Seville, University Hospital Virgen del Rocío, Consejo Superior de Investigaciones Científicas, University of Seville, Seville, Spain
| | - Gema Labrador Herrera
- Clinical Unit of Infectious Diseases, Microbiology, and Preventive Medicine, Institute of Biomedicine of Seville, University Hospital Virgen del Rocío, Consejo Superior de Investigaciones Científicas, University of Seville, Seville, Spain
| | - Andrea Miró Canturri
- Clinical Unit of Infectious Diseases, Microbiology, and Preventive Medicine, Institute of Biomedicine of Seville, University Hospital Virgen del Rocío, Consejo Superior de Investigaciones Científicas, University of Seville, Seville, Spain
| | - Jerónimo Pachón
- Clinical Unit of Infectious Diseases, Microbiology, and Preventive Medicine, Institute of Biomedicine of Seville, University Hospital Virgen del Rocío, Consejo Superior de Investigaciones Científicas, University of Seville, Seville, Spain
- Department of Medicine, University of Seville, Seville, Spain
| | - Younes Smani
- Clinical Unit of Infectious Diseases, Microbiology, and Preventive Medicine, Institute of Biomedicine of Seville, University Hospital Virgen del Rocío, Consejo Superior de Investigaciones Científicas, University of Seville, Seville, Spain
| | - María Eugenia Pachón-Ibáñez
- Clinical Unit of Infectious Diseases, Microbiology, and Preventive Medicine, Institute of Biomedicine of Seville, University Hospital Virgen del Rocío, Consejo Superior de Investigaciones Científicas, University of Seville, Seville, Spain
- Department of Medicine, University of Seville, Seville, Spain
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16
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Abstract
ABSTRACT Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) are caused by an exaggerated inflammatory response arising from a wide variety of pulmonary and systemic insults. Lung tissue is composed of a variety of cell populations, including parenchymal and immune cells. Emerging evidence has revealed that multiple cell populations in the lung work in concert to regulate lung inflammation in response to both direct and indirect stimulations. To date, the question of how different types of pulmonary cells communicate with each other and subsequently regulate or modulate inflammatory cascades remains to be fully addressed. In this review, we provide an overview of current advancements in understanding the role of cell-cell interaction in the development of ALI and depict molecular mechanisms by which cell-cell interactions regulate lung inflammation, focusing on inter-cellular activities and signaling pathways that point to possible therapeutic opportunities for ALI/ARDS.
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Affiliation(s)
- Huiting Zhou
- Department of Surgery, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
- Institute of Pediatric Research, Children’s Hospital of Soochow University, Suzhou, China
| | - Erica K. Fan
- Department of Epidemiology, University of Pittsburgh Graduate School of Public Health, Pittsburgh, Pennsylvania
| | - Jie Fan
- Department of Surgery, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
- Research and Development, Veterans Affairs Pittsburgh Healthcare System, Pittsburgh, Pennsylvania
- McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania
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17
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Marina CL, Bürgel PH, Agostinho DP, Zamith-Miranda D, Las-Casas LDO, Tavares AH, Nosanchuk JD, Bocca AL. Nutritional Conditions Modulate C. neoformans Extracellular Vesicles' Capacity to Elicit Host Immune Response. Microorganisms 2020; 8:E1815. [PMID: 33217920 PMCID: PMC7698703 DOI: 10.3390/microorganisms8111815] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 11/10/2020] [Accepted: 11/13/2020] [Indexed: 12/11/2022] Open
Abstract
Cryptococcus neoformans is a human pathogenic fungus that mainly afflicts immunocompromised patients. One of its virulence strategies is the production of extracellular vesicles (EVs), containing cargo with immunomodulatory properties. We evaluated EV's characteristics produced by capsular and acapsular strains of C. neoformans (B3501 and ΔCap67, respectively) growing in nutritionally poor or rich media and co-cultures with bone marrow-derived macrophages or dendritic cells from C57BL/6 mice. EVs produced under a poor nutritional condition displayed a larger hydrodynamic size, contained more virulence compounds, and induced a more robust inflammatory pattern than those produced in a rich nutritional medium, independently of strain. We treated infected mice with EVs produced in the rich medium, and the EVs inhibited more genes related to the inflammasome than untreated infected mice. These findings suggest that the EVs participate in the pathogenic processes that result in the dissemination of C. neoformans. Thus, these results highlight the versatility of EVs' properties during infection by C. neoformans in different tissues and support ongoing efforts to harness EVs to prevent and treat cryptococcosis.
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Affiliation(s)
- Clara Luna Marina
- Laboratory of Applied Immunity, Institute of Biology Sciences, University of Brasília, Brasília, Distrito Federal 70910-900, Brazil; (C.L.M.); (P.H.B.); (L.d.O.L.-C.)
| | - Pedro Henrique Bürgel
- Laboratory of Applied Immunity, Institute of Biology Sciences, University of Brasília, Brasília, Distrito Federal 70910-900, Brazil; (C.L.M.); (P.H.B.); (L.d.O.L.-C.)
| | - Daniel Paiva Agostinho
- Division of Infectious Diseases, Department of Medicine, Albert Einstein College of Medicine, New York, NY 10461, USA; (D.P.A.); (D.Z.-M.); (J.D.N.)
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York, NY 10461, USA
| | - Daniel Zamith-Miranda
- Division of Infectious Diseases, Department of Medicine, Albert Einstein College of Medicine, New York, NY 10461, USA; (D.P.A.); (D.Z.-M.); (J.D.N.)
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York, NY 10461, USA
| | - Lucas de Oliveira Las-Casas
- Laboratory of Applied Immunity, Institute of Biology Sciences, University of Brasília, Brasília, Distrito Federal 70910-900, Brazil; (C.L.M.); (P.H.B.); (L.d.O.L.-C.)
| | | | - Joshua Daniel Nosanchuk
- Division of Infectious Diseases, Department of Medicine, Albert Einstein College of Medicine, New York, NY 10461, USA; (D.P.A.); (D.Z.-M.); (J.D.N.)
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York, NY 10461, USA
| | - Anamelia Lorenzetti Bocca
- Laboratory of Applied Immunity, Institute of Biology Sciences, University of Brasília, Brasília, Distrito Federal 70910-900, Brazil; (C.L.M.); (P.H.B.); (L.d.O.L.-C.)
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18
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Islam ABMMK, Khan MAAK. Lung transcriptome of a COVID-19 patient and systems biology predictions suggest impaired surfactant production which may be druggable by surfactant therapy. Sci Rep 2020; 10:19395. [PMID: 33173052 PMCID: PMC7656460 DOI: 10.1038/s41598-020-76404-8] [Citation(s) in RCA: 55] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Accepted: 10/28/2020] [Indexed: 12/12/2022] Open
Abstract
An incomplete understanding of the molecular mechanisms behind impairment of lung pathobiology by COVID-19 complicates its clinical management. In this study, we analyzed the gene expression pattern of cells obtained from biopsies of COVID-19-affected patient and compared to the effects observed in typical SARS-CoV-2 and SARS-CoV-infected cell-lines. We then compared gene expression patterns of COVID-19-affected lung tissues and SARS-CoV-2-infected cell-lines and mapped those to known lung-related molecular networks, including hypoxia induced responses, lung development, respiratory processes, cholesterol biosynthesis and surfactant metabolism; all of which are suspected to be downregulated following SARS-CoV-2 infection based on the observed symptomatic impairments. Network analyses suggest that SARS-CoV-2 infection might lead to acute lung injury in COVID-19 by affecting surfactant proteins and their regulators SPD, SPC, and TTF1 through NSP5 and NSP12; thrombosis regulators PLAT, and EGR1 by ORF8 and NSP12; and mitochondrial NDUFA10, NDUFAF5, and SAMM50 through NSP12. Furthermore, hypoxia response through HIF-1 signaling might also be targeted by SARS-CoV-2 proteins. Drug enrichment analysis of dysregulated genes has allowed us to propose novel therapies, including lung surfactants, respiratory stimulants, sargramostim, and oseltamivir. Our study presents a distinct mechanism of probable virus induced lung damage apart from cytokine storm.
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19
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Bertelsen A, Elborn SJ, Schock BC. Toll like Receptor signalling by Prevotella histicola activates alternative NF-κB signalling in Cystic Fibrosis bronchial epithelial cells compared to P. aeruginosa. PLoS One 2020; 15:e0235803. [PMID: 33031374 PMCID: PMC7544055 DOI: 10.1371/journal.pone.0235803] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Accepted: 09/17/2020] [Indexed: 12/13/2022] Open
Abstract
Cystic Fibrosis (CF), caused by mutations affecting the CFTR gene, is characterised by viscid secretions in multiple organ systems. CF airways contain thick mucus, creating a gradient of hypoxia, which promotes the establishment of polymicrobial infection. Such inflammation predisposes to further infection, a self-perpetuating cycle in mediated by NF-κB. Anaerobic Gram-negative Prevotella spp. are found in sputum from healthy volunteers and CF patients and in CF lungs correlate with reduced levels of inflammation. Prevotella histicola (P. histicola) can suppress murine lung inflammation, however, no studies have examined the role of P. histicola in modulating infection and inflammation in the CF airways. We investigated innate immune signalling and NF-kB activation in CF epithelial cells CFBE41o- in response to clinical stains of P. histicola and Pseudomonas aeruginosa (P. aeruginosa). Toll-Like Receptor (TLR) expressing HEK-293 cells and siRNA assays for TLRs and IKKα were used to confirm signalling pathways. We show that P. histicola infection activated the alternative NF-kB signalling pathway in CF bronchial epithelial cells inducing HIF-1α protein. TLR5 signalling was responsible for the induction of the alternative NF-kB pathway through phosphorylation of IKKα. The induction of transcription factor HIF-1α was inversely associated with the induction of the alternative NF-kB pathway and knockdown of IKKα partially restored canonical NF-kB activation in response to P. histicola. This study demonstrates that different bacterial species in the respiratory microbiome can contribute differently to inflammation, either by activating inflammatory cascades (P. aeruginosa) or by muting the inflammatory response by modulating similar or related pathways (P. histicola). Further work is required to assess the complex interactions of the lung microbiome in response to mixed bacterial infections and their effects in people with CF.
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Affiliation(s)
- Anne Bertelsen
- Wellcome-Wolfson Institute for Experimental Medicine, Queens University Belfast, Belfast, United Kingdom
- Department of Medicine, University of Cambridge, Addenbrookes Hospital, Cambridge, United Kingdom
| | - Stuart J. Elborn
- Wellcome-Wolfson Institute for Experimental Medicine, Queens University Belfast, Belfast, United Kingdom
- Imperial College London, London, United Kingdom
| | - Bettina C. Schock
- Wellcome-Wolfson Institute for Experimental Medicine, Queens University Belfast, Belfast, United Kingdom
- * E-mail:
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The Underlying Causes of Respiratory Distress in Late-Preterm and Full-Term Infants Are Different From Those of Early-Preterm Infants. IRANIAN JOURNAL OF PEDIATRICS 2020. [DOI: 10.5812/ijp.104011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Background: A diagnosis of neonatal respiratory distress syndrome (RDS) is common among newborns in China. Some late-preterm and full-term (LP/FT) infants with respiratory distress (RD) symptoms but not primary surfactant deficiency are also diagnosed with RDS and given exogenous surfactant replacement therapy (SRT). Objectives: An increasing number of neonatologists have proposed that RD etiologies should be specifically classified to guide clinical treatment. Methods: The therapeutic effects of SRT on infants of different gestational ages (GAs) were compared in a large retrospective multicenter cohort study performed at 26 Neonatal Intensive Care units in China. The cause of RD at different GAs was further analyzed by comparing the different risk factors closely related to RDS severity at different GAs. Results: Analysis of 1240 infants diagnosed with RDS showed that SRT was less effective in LP/FT infants than in early-preterm (EP) infants. GA < 30 weeks and no prenatal corticosteroid use were closely related to RDS severity in EP infants, whereas perinatal infection- and perinatal hypoxia-associated risk factors and a high cesarean rate were closely related to RDS severity in LP/FT infants. Conclusions: The causes of RD might differ between LP/FT and EP infants, and the diagnosis of RDS might be overused in LP/FT infants. RD in LP/FT infants is more likely related to perinatal infection, perinatal hypoxia, elective cesarean and hereditary factors, which are important causes of neonatal pulmonary edema. New strategies for the treatment of refractory RD in LP/FT infants should concentrate more on pulmonary edema and neonatal ARDS.
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21
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Abstract
Recent years have witnessed an emergence of interest in understanding metabolic changes associated with immune responses, termed immunometabolism. As oxygen is central to all aerobic metabolism, hypoxia is now recognized to contribute fundamentally to inflammatory and immune responses. Studies from a number of groups have implicated a prominent role for oxygen metabolism and hypoxia in innate immunity of healthy tissue (physiologic hypoxia) and during active inflammation (inflammatory hypoxia). This inflammatory hypoxia emanates from a combination of recruited inflammatory cells (e.g., neutrophils, eosinophils, and monocytes), high rates of oxidative metabolism, and the activation of multiple oxygen-consuming enzymes during inflammation. These localized shifts toward hypoxia have identified a prominent role for the transcription factor hypoxia-inducible factor (HIF) in the regulation of innate immunity. Such studies have provided new and enlightening insight into our basic understanding of immune mechanisms, and extensions of these findings have identified potential therapeutic targets. In this review, we summarize recent literature around the topic of innate immunity and mucosal hypoxia with a focus on transcriptional responses mediated by HIF.
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Affiliation(s)
- Sean P Colgan
- Department of Medicine, University of Colorado School of Medicine, Aurora, Colorado 80045, USA;
- Mucosal Inflammation Program, University of Colorado School of Medicine, Aurora, Colorado 80045, USA
| | - Glenn T Furuta
- Mucosal Inflammation Program, University of Colorado School of Medicine, Aurora, Colorado 80045, USA
- Department of Pediatrics, University of Colorado School of Medicine, Aurora, Colorado 80045, USA
| | - Cormac T Taylor
- UCD Conway Institute, Systems Biology Ireland and School of Medicine, University College Dublin, Belfield, Dublin 4, Ireland
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22
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Abstract
Redox signalling in the gastrointestinal mucosa is held in an intricate balance. Potent microbicidal mechanisms can be used by infiltrating immune cells, such as neutrophils, to protect compromised mucosae from microbial infection through the generation of reactive oxygen species. Unchecked, collateral damage to the surrounding tissue from neutrophil-derived reactive oxygen species can be detrimental; thus, maintenance and restitution of a breached intestinal mucosal barrier are paramount to host survival. Redox reactions and redox signalling have been studied for decades with a primary focus on contributions to disease processes. Within the past decade, an upsurge of exciting findings have implicated subtoxic levels of oxidative stress in processes such as maintenance of mucosal homeostasis, the control of protective inflammation and even regulation of tissue wound healing. Resident gut microbial communities have been shown to trigger redox signalling within the mucosa, which expresses similar but distinct enzymes to phagocytes. At the fulcrum of this delicate balance is the colonic mucosal epithelium, and emerging evidence suggests that precise control of redox signalling by these barrier-forming cells may dictate the outcome of an inflammatory event. This Review will address both the spectrum and intensity of redox activity pertaining to host-immune and host-microbiota crosstalk during homeostasis and disease processes in the gastrointestinal tract.
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Effect of Hypoxia on the Pathogenesis of Acinetobacter baumannii and Pseudomonas aeruginosa In Vitro and in Murine Experimental Models of Infection. Infect Immun 2018; 86:IAI.00543-18. [PMID: 30082478 PMCID: PMC6204731 DOI: 10.1128/iai.00543-18] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Accepted: 07/27/2018] [Indexed: 12/18/2022] Open
Abstract
Hypoxia modulates bacterial virulence and the inflammation response through hypoxia-inducible factor 1α (HIF-1α). Here we study the influence of hypoxia on Acinetobacter baumannii and Pseudomonas aeruginosa infections. In vitro, hypoxia increases the bactericidal activities of epithelial cells against A. baumannii and P. aeruginosa, reducing extracellular bacterial concentrations to 50.5% ± 7.5% and 90.8% ± 13.9%, respectively, at 2 h postinfection. The same phenomenon occurs in macrophages (67.6% ± 18.2% for A. baumannii at 2 h and 50.3% ± 10.9% for P. aeruginosa at 24 h). Hypoxia decreases the adherence of A. baumannii to epithelial cells (42.87% ± 8.16% at 2 h) and macrophages (52.0% ± 18.7% at 24 h), as well as that of P. aeruginosa (24.9% ± 4.5% in epithelial cells and 65.7% ± 5.5% in macrophages at 2 h). Moreover, hypoxia decreases the invasion of epithelial cells (48.6% ± 3.8%) and macrophages (8.7% ± 6.9%) by A. baumannii at 24 h postinfection and by P. aeruginosa at 2 h postinfection (75.0% ± 16.3% and 63.4% ± 5.4%, respectively). In vivo, hypoxia diminishes bacterial loads in fluids and tissues in animal models of infection by both pathogens. In contrast, mouse survival time was shorter under hypoxia (23.92 versus 36.42 h) with A. baumannii infection. No differences in the production of cytokines or HIF-1α were found between hypoxia and normoxia in vitro or in vivo We conclude that hypoxia increases the bactericidal activities of host cells against both pathogens and reduces the interaction of pathogens with host cells. Moreover, hypoxia accelerates the rate at which animals die despite the lower bacterial concentrations in vivo.
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Abstract
Mucosal tissues represent surfaces that are exposed to the outside world and provide a conduit for internal and external communication. Tissues such as the intestine and the lung are lined by layer(s) of epithelial cells that, when organized in three dimensions, provide a critical barrier to the flux of luminal contents. This selective barrier is provided through the regulated expression of junctional proteins and mucins. Tissue oxygen metabolism is central to the maintenance of homeostasis in the mucosa. In some organs (e.g., the colon), low baseline Po2 determines tissue metabolism and results in basal expression of the transcription factor, hypoxia-inducible factor (HIF), which is enhanced after ischemia/inflammation. Recent studies have indicated that HIF contributes fundamentally to the expression of barrier-related genes and in the regulation of barrier-adaptive responses within the mucosa. Here, we briefly review recent literature on the topic of hypoxia and HIF regulation of barrier in mucosal health and during disease.
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25
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Taylor CT, Colgan SP. Regulation of immunity and inflammation by hypoxia in immunological niches. Nat Rev Immunol 2017; 17:774-785. [PMID: 28972206 PMCID: PMC5799081 DOI: 10.1038/nri.2017.103] [Citation(s) in RCA: 398] [Impact Index Per Article: 56.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Immunological niches are focal sites of immune activity that can have varying microenvironmental features. Hypoxia is a feature of physiological and pathological immunological niches. The impact of hypoxia on immunity and inflammation can vary depending on the microenvironment and immune processes occurring in a given niche. In physiological immunological niches, such as the bone marrow, lymphoid tissue, placenta and intestinal mucosa, physiological hypoxia controls innate and adaptive immunity by modulating immune cell proliferation, development and effector function, largely via transcriptional changes driven by hypoxia-inducible factor (HIF). By contrast, in pathological immunological niches, such as tumours and chronically inflamed, infected or ischaemic tissues, pathological hypoxia can drive tissue dysfunction and disease development through immune cell dysregulation. Here, we differentiate between the effects of physiological and pathological hypoxia on immune cells and the consequences for immunity and inflammation in different immunological niches. Furthermore, we discuss the possibility of targeting hypoxia-sensitive pathways in immune cells for the treatment of inflammatory disease.
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Affiliation(s)
- Cormac T Taylor
- UCD Conway Institute, Systems Biology Ireland and the School of Medicine, University College Dublin, Belfield, Dublin 4, Ireland
| | - Sean P Colgan
- Department of Medicine and the Mucosal Inflammation Program, University of Colorado School of Medicine, Aurora, 80045 Colorado, USA
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26
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Campbell EL, Kao DJ, Colgan SP. Neutrophils and the inflammatory tissue microenvironment in the mucosa. Immunol Rev 2017; 273:112-20. [PMID: 27558331 DOI: 10.1111/imr.12456] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The interaction of neutrophils (PMNs) and epithelial cells are requisite lines of communication during mucosal inflammatory responses. Consequences of such interactions often determine endpoint organ function, and for this reason, much interest has developed around defining the constituents of the tissue microenvironment of inflammatory lesions. Physiologic in vitro and in vivo models have aided in the discovery of components that define the basic inflammatory machinery that mold the inflammatory tissue microenvironment. Here, we will review the recent literature related to the contribution of PMNs to molding of the tissue microenvironment, with an emphasis on the gastrointestinal (GI) tract. We focus on endogenous pathways for promoting tissue homeostasis and the molecular determinants of neutrophil-epithelial cell interactions during ongoing inflammation. These recent studies highlight the dynamic nature of these pathways and lend insight into the complexity of treating mucosal inflammation.
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Affiliation(s)
- Eric L Campbell
- Department of Medicine the Mucosal Inflammation Program, University of Colorado School of Medicine, Aurora, CO, USA
| | - Daniel J Kao
- Department of Medicine the Mucosal Inflammation Program, University of Colorado School of Medicine, Aurora, CO, USA
| | - Sean P Colgan
- Department of Medicine the Mucosal Inflammation Program, University of Colorado School of Medicine, Aurora, CO, USA
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27
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Colgan SP, Campbell EL, Kominsky DJ. Hypoxia and Mucosal Inflammation. ANNUAL REVIEW OF PATHOLOGY-MECHANISMS OF DISEASE 2017; 11:77-100. [PMID: 27193451 DOI: 10.1146/annurev-pathol-012615-044231] [Citation(s) in RCA: 86] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Sites of inflammation are defined by significant changes in metabolic activity. Recent studies have suggested that O2 metabolism and hypoxia play a prominent role in inflammation so-called "inflammatory hypoxia," which results from a combination of recruited inflammatory cells (e.g., neutrophils and monocytes), the local proliferation of multiple cell types, and the activation of multiple O2-consuming enzymes during inflammation. These shifts in energy supply and demand result in localized regions of hypoxia and have revealed the important function off the transcription factor HIF (hypoxia-inducible factor) in the regulation of key target genes that promote inflammatory resolution. Analysis of these pathways has provided multiple opportunities for understanding basic mechanisms of inflammation and has defined new targets for intervention. Here, we review recent work addressing tissue hypoxia and metabolic control of inflammation and immunity.
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Affiliation(s)
- Sean P Colgan
- Department of Medicine, University of Colorado School of Medicine, Aurora, Colorado 80045; .,Mucosal Inflammation Program, University of Colorado School of Medicine, Aurora, Colorado 80045
| | - Eric L Campbell
- Department of Medicine, University of Colorado School of Medicine, Aurora, Colorado 80045; .,Mucosal Inflammation Program, University of Colorado School of Medicine, Aurora, Colorado 80045
| | - Douglas J Kominsky
- Mucosal Inflammation Program, University of Colorado School of Medicine, Aurora, Colorado 80045.,Department of Microbiology and Immunology, Montana State University, Bozeman, Montana 59717
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28
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Humphries CP. Lower Respiratory Tract Infection: An Unrecognised Risk Factor for High Altitude Pulmonary Oedema? Eur J Case Rep Intern Med 2017; 4:000539. [PMID: 30755928 PMCID: PMC6346869 DOI: 10.12890/2017_000539] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Accepted: 12/16/2016] [Indexed: 12/02/2022] Open
Abstract
The case of a 25-year-old expedition doctor who developed high altitude pulmonary oedema (HAPE) while climbing in the Swiss Alps is presented, with reference to the literature. The patient’s symptoms of HAPE were typical. Less typical was the fact that the doctor had previously been to similar altitudes uneventfully. The only differentiator is that on this expedition he developed a mild lower respiratory tract infection (LRTI) 2 days prior to travel. There has been limited, conflicting evidence regarding LRTI as a risk factor for HAPE and high quality research has not focused on this area. LRTI is not commonly recognised as being a risk in high altitude environments, which may be resulting in lethal consequences. This report aims to inform, provide a clinical question for future high altitude research expeditions, and encourage consideration by expedition and high altitude doctors.
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Fagundes RR, Taylor CT. Determinants of hypoxia-inducible factor activity in the intestinal mucosa. J Appl Physiol (1985) 2017; 123:1328-1334. [PMID: 28408694 DOI: 10.1152/japplphysiol.00203.2017] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2017] [Revised: 03/28/2017] [Accepted: 04/07/2017] [Indexed: 12/16/2022] Open
Abstract
The intestinal mucosa is exposed to fluctuations in oxygen levels due to constantly changing rates of oxygen demand and supply and its juxtaposition with the anoxic environment of the intestinal lumen. This frequently results in a state of hypoxia in the healthy mucosa even in the physiologic state. Furthermore, pathophysiologic hypoxia (which is more severe and extensive) is associated with chronic inflammatory diseases including inflammatory bowel disease (IBD). The hypoxia-inducible factor (HIF), a ubiquitously expressed regulator of cellular adaptation to hypoxia, is central to both the adaptive and the inflammatory responses of cells of the intestinal mucosa in IBD patients. In this review, we discuss the microenvironmental factors which influence the level of HIF activity in healthy and inflamed intestinal mucosae and the consequences that increased HIF activity has for tissue function and disease progression.
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Affiliation(s)
- Raphael R Fagundes
- Graduate School of Medical Sciences, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands; and.,UCD Conway Institute, Systems Biology Ireland and School of Medicine, University College Dublin, Belfield, Dublin, Ireland
| | - Cormac T Taylor
- UCD Conway Institute, Systems Biology Ireland and School of Medicine, University College Dublin, Belfield, Dublin, Ireland
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30
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Chun C, Zheng L, Colgan SP. Tissue metabolism and host-microbial interactions in the intestinal mucosa. Free Radic Biol Med 2017; 105:86-92. [PMID: 27687211 PMCID: PMC5797701 DOI: 10.1016/j.freeradbiomed.2016.09.027] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/12/2016] [Revised: 09/23/2016] [Accepted: 09/26/2016] [Indexed: 01/03/2023]
Abstract
In recent years, studies in the gastrointestinal (GI) mucosa have taught us a number of important lessons related to tissue oxygenation and metabolism in health and disease. The highly vascularized mucosa lies immediately adjacent to an anaerobic lumen containing trillions of metabolically active microbes (i.e. the microbiome) that results in one of the more austere tissue microenvironments in the body. These studies have also implicated a prominent role for oxygen metabolism and hypoxia in inflammation, so called "inflammatory hypoxia", that results from the activation of multiple oxygen consuming enzymes. Inflammation-associated shifts in the composition of the microbiome and microbial-derived metabolites have revealed a prominent role for the transcription factor hypoxia-inducible factor (HIF) in the regulation of key target genes that promote inflammatory resolution. Analyses of these pathways have provided a multitude of opportunities for understanding basic mechanisms of both homeostasis and disease and have defined new targets for intervention. Here, we review recent advances in our understanding of metabolic influences on host-microbe interactions in the GI mucosa.
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Affiliation(s)
- Carlene Chun
- Department of Medicine and the Mucosal Inflammation Program, University of Colorado School of Medicine, Aurora, CO, United States
| | - Leon Zheng
- Department of Medicine and the Mucosal Inflammation Program, University of Colorado School of Medicine, Aurora, CO, United States
| | - Sean P Colgan
- Department of Medicine and the Mucosal Inflammation Program, University of Colorado School of Medicine, Aurora, CO, United States.
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31
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Polke M, Seiler F, Lepper PM, Kamyschnikow A, Langer F, Monz D, Herr C, Bals R, Beisswenger C. Hypoxia and the hypoxia-regulated transcription factor HIF-1α suppress the host defence of airway epithelial cells. Innate Immun 2017; 23:373-380. [PMID: 28409544 DOI: 10.1177/1753425917698032] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Chronic diseases of the respiratory tract, such as cystic fibrosis, are associated with mucosal and systemic hypoxia. Innate immune functions of airway epithelial cells are required to prevent and control infections of the lung parenchyma. The transcription factor hypoxia-inducible factor 1α (HIF-1α) regulates cellular adaptation to low oxygen conditions. Here, we show that hypoxia and HIF-1α regulate innate immune mechanisms of cultured human bronchial epithelial cells (HBECs). Exposure of primary HBECs to hypoxia or the prolyl hydroxylase inhibitor dimethyloxaloylglycine (DMOG) resulted in a significantly decreased expression of inflammatory mediators (IL-6, IFN-γ-induced protein 10) in response to ligands for TLRs (flagellin, polyI:C) and Pseudomonas aeruginosa, whereas the expression of inflammatory mediators was not affected by hypoxia or DMOG in the absence of microbial factors. Small interfering RNA-mediated knockdown of HIF-1α in HBECs and in the bronchial epithelial cell line Calu-3 resulted in increased expression of inflammatory mediators. The inflammatory response was decreased in lungs of mice stimulated with inactivated P. aeruginosa under hypoxia. These data suggest that hypoxia suppresses the innate immune response of airway epithelial cells via HIF-1α.
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Affiliation(s)
- Markus Polke
- 1 Department of Internal Medicine V - Pulmonology, Allergology and Critical Care Medicine, Saarland University, Homburg, Germany
| | - Frederik Seiler
- 1 Department of Internal Medicine V - Pulmonology, Allergology and Critical Care Medicine, Saarland University, Homburg, Germany
| | - Philipp M Lepper
- 1 Department of Internal Medicine V - Pulmonology, Allergology and Critical Care Medicine, Saarland University, Homburg, Germany
| | - Andreas Kamyschnikow
- 1 Department of Internal Medicine V - Pulmonology, Allergology and Critical Care Medicine, Saarland University, Homburg, Germany
| | - Frank Langer
- 2 Department of Thoracic and Cardiovascular Surgery, Saarland University, Homburg, Germany
| | - Dominik Monz
- 3 Department of Pediatrics and Neonatology, Saarland University, Homburg, Germany
| | - Christian Herr
- 1 Department of Internal Medicine V - Pulmonology, Allergology and Critical Care Medicine, Saarland University, Homburg, Germany
| | - Robert Bals
- 1 Department of Internal Medicine V - Pulmonology, Allergology and Critical Care Medicine, Saarland University, Homburg, Germany
| | - Christoph Beisswenger
- 1 Department of Internal Medicine V - Pulmonology, Allergology and Critical Care Medicine, Saarland University, Homburg, Germany
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32
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Chen T, Yang C, Li M, Tan X. Alveolar Hypoxia-Induced Pulmonary Inflammation: From Local Initiation to Secondary Promotion by Activated Systemic Inflammation. J Vasc Res 2016; 53:317-329. [PMID: 27974708 DOI: 10.1159/000452800] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Accepted: 10/23/2016] [Indexed: 11/19/2022] Open
Abstract
Pulmonary hypertension (PH) is a pathological condition with high mortality and morbidity. Hypoxic PH (HPH) is a common form of PH occurring mainly due to lung disease and/or hypoxia. Most causes of HPH are associated with persistent or intermittent alveolar hypoxia, including exposure to high altitude and chronic obstructive respiratory disease. Recent evidence suggests that inflammation is a critical step for HPH initiation and development. A detailed understanding of the initiation and progression of pulmonary inflammation would help in exploring potential clinical treatments for HPH. In this review, the mechanism for alveolar hypoxia-induced local lung inflammation and its progression are discussed as follows: (1) low alveolar PO2 levels activate resident lung cells, mainly the alveolar macrophages, which initiate pulmonary inflammation; (2) systemic inflammation is induced by alveolar hypoxia through alveolar macrophage activation; (3) monocytes are recruited into the pulmonary circulation by alveolar hypoxia-induced macrophage activation, which then contributes to the progression of pulmonary inflammation during the chronic phase of alveolar hypoxia, and (4) alveolar hypoxia-induced systemic inflammation contributes to the development of HPH. We hypothesize that a combination of alveolar hypoxia-induced local lung inflammation and the initiation of systemic inflammation ("second hit") is essential for HPH progression.
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Affiliation(s)
- Ting Chen
- Department of High Altitude Physiology and Biology, College of High Altitude Medicine, Third Military Medical University, Ministry of Education, Chongqing, China
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33
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Tomechko SE, Lundberg KC, Jarvela J, Bebek G, Chesnokov NG, Schlatzer D, Ewing RM, Boom WH, Chance MR, Silver RF. Proteomic and bioinformatics profile of paired human alveolar macrophages and peripheral blood monocytes. Proteomics 2016; 15:3797-805. [PMID: 26389541 DOI: 10.1002/pmic.201400496] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2014] [Revised: 07/28/2015] [Accepted: 09/15/2015] [Indexed: 01/10/2023]
Abstract
Little is known about proteomic differences between pluripotent human peripheral blood monocytes (MN) and their terminally-differentiated pulmonary counterparts, alveolar macrophages (AM). To better characterize these cell populations, we performed a label-free shotgun proteomics assessment of matched AM and MN preparations from eight healthy volunteers. With an FDR of less than 0.45%, we identified 1754 proteins within AM and 1445 from MN. Comparison of the two proteomes revealed that 1239 of the proteins found in AM were shared with MN, whereas 206 proteins were uniquely identified in MN and 515 were unique to AM. Molecular and cellular functions, protein classes, development associations, and membership in physiological systems and canonical pathways were identified among the detected proteins. Analysis of biologic processes represented by these proteomes indicated that MN were most prominently enriched for proteins involved in cellular movement and immune cell trafficking. In contrast, AM were enriched for proteins involved in protein trafficking, molecular transport, and cellular assembly and organization. These findings provide a baseline proteomic resource for further studies aimed at better understanding of the functional differences between MN and AM in both health and disease.
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Affiliation(s)
- Sara E Tomechko
- Center for Proteomics and Bioinformatics, Case Western Reserve University, Cleveland, OH, USA.,Division of Pulmonary, Critical Care, and Sleep Medicine, Case Western Reserve University School of Medicine, Cleveland, OH, USA
| | - Kathleen C Lundberg
- Center for Proteomics and Bioinformatics, Case Western Reserve University, Cleveland, OH, USA
| | - Jessica Jarvela
- Division of Pulmonary, Critical Care, and Sleep Medicine, Case Western Reserve University School of Medicine, Cleveland, OH, USA.,The Louis Stokes Cleveland Department of Veterans' Affairs Medical Center, Cleveland, OH, USA
| | - Gurkan Bebek
- Center for Proteomics and Bioinformatics, Case Western Reserve University, Cleveland, OH, USA
| | - Nicole G Chesnokov
- Center for Proteomics and Bioinformatics, Case Western Reserve University, Cleveland, OH, USA
| | - Daniela Schlatzer
- Center for Proteomics and Bioinformatics, Case Western Reserve University, Cleveland, OH, USA
| | - Rob M Ewing
- Center for Proteomics and Bioinformatics, Case Western Reserve University, Cleveland, OH, USA
| | - W Henry Boom
- University Hospitals Case Medical Center, Cleveland, OH, USA.,Division of Infectious Diseases and HIV Medicine, Case Western Reserve University, Cleveland, OH, USA
| | - Mark R Chance
- Center for Proteomics and Bioinformatics, Case Western Reserve University, Cleveland, OH, USA
| | - Richard F Silver
- Division of Pulmonary, Critical Care, and Sleep Medicine, Case Western Reserve University School of Medicine, Cleveland, OH, USA.,The Louis Stokes Cleveland Department of Veterans' Affairs Medical Center, Cleveland, OH, USA.,University Hospitals Case Medical Center, Cleveland, OH, USA
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34
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Glover LE, Lee JS, Colgan SP. Oxygen metabolism and barrier regulation in the intestinal mucosa. J Clin Invest 2016; 126:3680-3688. [PMID: 27500494 DOI: 10.1172/jci84429] [Citation(s) in RCA: 98] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Mucosal surfaces are lined by epithelial cells and provide an important barrier to the flux of antigens from the outside. This barrier is provided at a number of levels, including epithelial junctional complexes, mucus production, and mucosa-derived antimicrobials. Tissue metabolism is central to the maintenance of homeostasis in the mucosa. In the intestine, for example, baseline pO2 levels are uniquely low due to counter-current blood flow and the presence of large numbers of bacteria. As such, hypoxia and HIF signaling predominates normal intestinal metabolism and barrier regulation during both homeostasis and active inflammation. Contributing factors that elicit important adaptive responses within the mucosa include the transcriptional regulation of tight junction proteins, metabolic regulation of barrier components, and changes in autophagic flux. Here, we review recent literature around the topic of hypoxia and barrier function in health and during disease.
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35
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Fliesser M, Wallstein M, Kurzai O, Einsele H, Löffler J. Hypoxia attenuates anti-Aspergillus fumigatusimmune responses initiated by human dendritic cells. Mycoses 2016; 59:503-8. [DOI: 10.1111/myc.12498] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2015] [Revised: 02/25/2016] [Accepted: 02/25/2016] [Indexed: 12/26/2022]
Affiliation(s)
- Mirjam Fliesser
- Medical Clinic and Polyclinic II; University Hospital; Wuerzburg Germany
| | - Marion Wallstein
- Medical Clinic and Polyclinic II; University Hospital; Wuerzburg Germany
| | - Oliver Kurzai
- Septomics Research Centre; Friedrich Schiller University and Leibniz Institute for Natural Product Research and Infection Biology-Hans Knoell Institute; Jena Germany
| | - Hermann Einsele
- Medical Clinic and Polyclinic II; University Hospital; Wuerzburg Germany
| | - Jürgen Löffler
- Medical Clinic and Polyclinic II; University Hospital; Wuerzburg Germany
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36
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Huang CB, Alimova Y, Ebersole JL. Macrophage polarization in response to oral commensals and pathogens. Pathog Dis 2016; 74:ftw011. [PMID: 26884502 DOI: 10.1093/femspd/ftw011] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/03/2016] [Indexed: 01/03/2023] Open
Abstract
Macrophages have been identified in the periodontium. Data have phenotypically described these cells, demonstrated changes with progressing periodontal disease, and identified their ability to function in antigen-presentation critical for adaptive immune responses to individual oral bacterium. Recent evidence has emphasized an important role for the plasticity of macrophage phenotypes, not only in the resulting function of these cells in various tissues, but also clear differences in the stimulatory signals that result in M1 (classical activation, inflammatory) and M2 (alternative activation/deactivated, immunomodulatory) cells. This investigation hypothesized that the oral pathogens, Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans induce M1-type cells, while oral commensal bacteria primarily elicit macrophage functions consistent with an M2 phenotype. However, we observed that the M1 output from P. gingivalis challenge, showed exaggerated levels of pro-inflammatory cytokines, with a much lower production of chemokines related to T-cell recruitment. This contrasted with A. actinomycetemcomitans infection that increased both the pro-inflammatory cytokines and T-cell chemokines. Thus, it appears that P. gingivalis, as an oral pathogen, may have a unique capacity to alter the programming of the M1 macrophage resulting in a hyperinflammatory environment and minimizing the ability for T-cell immunomodulatory influx into the lesions.
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Affiliation(s)
- Chifu B Huang
- Center for Oral Health Research, College of Dentistry, University of Kentucky, Lexington, KY 40536, USA
| | - Yelena Alimova
- Center for Oral Health Research, College of Dentistry, University of Kentucky, Lexington, KY 40536, USA
| | - Jeffrey L Ebersole
- Center for Oral Health Research, College of Dentistry, University of Kentucky, Lexington, KY 40536, USA
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37
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Abstract
In this review, I summarize some of the recent insight into pharmacological targeting of hypoxia in disease models. Studies from cultured cell systems, animal models, and translation to human patients have revealed that posttranslational modifications of individual proteins within NF-κB and hypoxia-inducible factor pathways serve as ideal targets for analysis in disease models. Studies defining differences and similarities between these responses have taught us a number of important lessons about the complexity of the inflammatory response. A clearer definition of these pathways has provided new insight into disease pathogenesis and, importantly, the potential for new therapeutic targets.
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38
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Roth JM, Köhler D, Schneider M, Granja TF, Rosenberger P. Semaphorin 7A Aggravates Pulmonary Inflammation during Lung Injury. PLoS One 2016; 11:e0146930. [PMID: 26752048 PMCID: PMC4720127 DOI: 10.1371/journal.pone.0146930] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2015] [Accepted: 12/17/2015] [Indexed: 01/11/2023] Open
Abstract
The extent of pulmonary inflammation during lung injury ultimately determines patient outcome. Pulmonary inflammation is initiated by the migration of neutrophils into the alveolar space. Recent work has demonstrated that the guidance protein semaphorin 7A (SEMA7A) influences the migration of neutrophils into hypoxic tissue sites, yet, its role during lung injury is not well understood. Here, we report that the expression of SEMA7A is induced in vitro through pro-inflammatory cytokines. SEMA7A itself induces the production of pro-inflammatory cytokines in endothelial and epithelial cells, enhancing pulmonary inflammation. The induction of SEMA7A facilitates the transendothelial migration of neutrophils. In vivo, animals with deletion of SEMA7A expression showed reduced signs of pulmonary inflammatory changes following lipopolysaccharide challenge. We define here the role of SEMA7A in the development of lung injury and identify a potential pathway to interfere with these detrimental changes. Future anti-inflammatory strategies for the treatment of lung injury might be based on this finding.
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Affiliation(s)
- Judith Marlene Roth
- Department of Anesthesiology and Intensive Care Medicine, Tübingen University Hospital, Tübingen, Germany
| | - David Köhler
- Department of Anesthesiology and Intensive Care Medicine, Tübingen University Hospital, Tübingen, Germany
| | - Mariella Schneider
- Department of Anesthesiology and Intensive Care Medicine, Tübingen University Hospital, Tübingen, Germany
| | - Tiago Folgosa Granja
- Department of Anesthesiology and Intensive Care Medicine, Tübingen University Hospital, Tübingen, Germany
| | - Peter Rosenberger
- Department of Anesthesiology and Intensive Care Medicine, Tübingen University Hospital, Tübingen, Germany
- * E-mail:
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39
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Jiang D, Tikhomirova A, Kidd SP. Haemophilus influenzae strains possess variations in the global transcriptional profile in response to oxygen levels and this influences sensitivity to environmental stresses. Res Microbiol 2015; 167:13-9. [PMID: 26362945 DOI: 10.1016/j.resmic.2015.08.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2015] [Revised: 08/05/2015] [Accepted: 08/27/2015] [Indexed: 01/22/2023]
Abstract
An alcohol dehydrogenase, AdhC, is required for Haemophilus influenzae Rd KW20 growth with high oxygen. AdhC protects against both exogenous and metabolically generated, endogenous reactive aldehydes. However, adhC in the strain 86-028NP is a pseudogene. Unlike the Rd KW20 adhC mutant, 86-028NP does grow with high oxygen. This suggests the differences between Rd KW20 and 86-028NP include broader pathways, such as for the maintenance of redox and metabolism that avoids the toxicity related to oxygen. We hypothesized that these differences affect their resistance to relevant toxic chemicals, including reactive aldehydes. Across a range of oxygen concentrations, despite the growth profiles of Rd KW20 and 86-028NP being similar, there was a significant variation in their sensitivity to reactive aldehydes. 86-028NP is more sensitive to methylglyoxal, formaldehyde and glycolaldehyde under high oxygen than low oxygen as well as compared to Rd KW20. Also, as oxygen levels changed the whole genome gene expression profiles of Rd KW20 and 86-028NP revealed distinctions in their transcriptomes (the iron, FNR and ArcAB regulons). These were indicative of a difference in their intracellular redox properties and we show it is this that underpins their survival against reactive aldehydes.
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Affiliation(s)
- Donald Jiang
- Research Centre for Infectious Diseases, School of Molecular and Biomedical Sciences, The University of Adelaide, North Terrace Campus, Adelaide, South Australia, 5005, Australia
| | - Alexandra Tikhomirova
- Research Centre for Infectious Diseases, School of Molecular and Biomedical Sciences, The University of Adelaide, North Terrace Campus, Adelaide, South Australia, 5005, Australia
| | - Stephen P Kidd
- Research Centre for Infectious Diseases, School of Molecular and Biomedical Sciences, The University of Adelaide, North Terrace Campus, Adelaide, South Australia, 5005, Australia.
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Zheng L, Kelly CJ, Colgan SP. Physiologic hypoxia and oxygen homeostasis in the healthy intestine. A Review in the Theme: Cellular Responses to Hypoxia. Am J Physiol Cell Physiol 2015; 309:C350-60. [PMID: 26179603 DOI: 10.1152/ajpcell.00191.2015] [Citation(s) in RCA: 295] [Impact Index Per Article: 32.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
In recent years, the intestinal mucosa has proven to be an intriguing organ to study tissue oxygenation. The highly vascularized lamina propria juxtaposed to an anaerobic lumen containing trillions of metabolically active microbes results in one of the most austere tissue microenvironments in the body. Studies to date have determined that a healthy mucosa contains a steep oxygen gradient along the length of the intestine and from the lumen to the serosa. Advances in technology have allowed multiple independent measures and indicate that, in the healthy mucosa of the small and large intestine, the lumen-apposed epithelia experience Po2 conditions of <10 mmHg, so-called physiologic hypoxia. This unique physiology results from a combination of factors, including countercurrent exchange blood flow, fluctuating oxygen demands, epithelial metabolism, and oxygen diffusion into the lumen. Such conditions result in the activation of a number of hypoxia-related signaling processes, including stabilization of the transcription factor hypoxia-inducible factor. Here, we review the principles of mucosal oxygen delivery, metabolism, and end-point functional responses that result from this unique oxygenation profile.
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Affiliation(s)
- Leon Zheng
- Department of Medicine and Mucosal Inflammation Program, University of Colorado School of Medicine, Aurora, Colorado
| | - Caleb J Kelly
- Department of Medicine and Mucosal Inflammation Program, University of Colorado School of Medicine, Aurora, Colorado
| | - Sean P Colgan
- Department of Medicine and Mucosal Inflammation Program, University of Colorado School of Medicine, Aurora, Colorado
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Anderson SL, Duke-Novakovski T, Singh B. The immune response to anesthesia: part 1. Vet Anaesth Analg 2014; 41:113-26. [PMID: 24588928 DOI: 10.1111/vaa.12125] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2013] [Accepted: 11/07/2013] [Indexed: 12/13/2022]
Abstract
OBJECTIVE To review the immune response to anesthesia including mechanical ventilation, inhaled anesthetic gases, and injectable anesthetics and sedatives. STUDY DESIGN Review. METHODS AND DATABASES Multiple literature searches were performed using PubMed and Google Scholar from spring 2012 through fall 2013. Relevant anesthetic and immune terms were used to search databases without year published or species constraints. The online database for Veterinary Anaesthesia and Analgesia and the Journal of Veterinary Emergency and Critical Care were searched by issue starting in 2000 for relevant articles. CONCLUSION Recent research data indicate that commonly used volatile anesthetic agents, such as isoflurane and sevoflurane, may have a protective effect on vital organs. With the lung as the target organ, protection using an appropriate anesthetic protocol may be possible during direct pulmonary insults, including mechanical ventilation, and during systemic disease processes, such as endotoxemia, generalized sepsis, and ischemia-reperfusion injury.
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Affiliation(s)
- Stacy L Anderson
- Department of Veterinary Biomedical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, SK, Canada
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Scotti JS, Leung IKH, Ge W, Bentley MA, Paps J, Kramer HB, Lee J, Aik W, Choi H, Paulsen SM, Bowman LAH, Loik ND, Horita S, Ho CH, Kershaw NJ, Tang CM, Claridge TDW, Preston GM, McDonough MA, Schofield CJ. Human oxygen sensing may have origins in prokaryotic elongation factor Tu prolyl-hydroxylation. Proc Natl Acad Sci U S A 2014; 111:13331-6. [PMID: 25197067 PMCID: PMC4169948 DOI: 10.1073/pnas.1409916111] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
The roles of 2-oxoglutarate (2OG)-dependent prolyl-hydroxylases in eukaryotes include collagen stabilization, hypoxia sensing, and translational regulation. The hypoxia-inducible factor (HIF) sensing system is conserved in animals, but not in other organisms. However, bioinformatics imply that 2OG-dependent prolyl-hydroxylases (PHDs) homologous to those acting as sensing components for the HIF system in animals occur in prokaryotes. We report cellular, biochemical, and crystallographic analyses revealing that Pseudomonas prolyl-hydroxylase domain containing protein (PPHD) contain a 2OG oxygenase related in structure and function to the animal PHDs. A Pseudomonas aeruginosa PPHD knockout mutant displays impaired growth in the presence of iron chelators and increased production of the virulence factor pyocyanin. We identify elongation factor Tu (EF-Tu) as a PPHD substrate, which undergoes prolyl-4-hydroxylation on its switch I loop. A crystal structure of PPHD reveals striking similarity to human PHD2 and a Chlamydomonas reinhardtii prolyl-4-hydroxylase. A crystal structure of PPHD complexed with intact EF-Tu reveals that major conformational changes occur in both PPHD and EF-Tu, including a >20-Å movement of the EF-Tu switch I loop. Comparison of the PPHD structures with those of HIF and collagen PHDs reveals conservation in substrate recognition despite diverse biological roles and origins. The observed changes will be useful in designing new types of 2OG oxygenase inhibitors based on various conformational states, rather than active site iron chelators, which make up most reported 2OG oxygenase inhibitors. Structurally informed phylogenetic analyses suggest that the role of prolyl-hydroxylation in human hypoxia sensing has ancient origins.
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Affiliation(s)
- John S Scotti
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Oxford OX1 3TA, United Kingdom
| | - Ivanhoe K H Leung
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Oxford OX1 3TA, United Kingdom
| | - Wei Ge
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Oxford OX1 3TA, United Kingdom; Chinese Academy of Medical Sciences, Beijing 100005, China
| | - Michael A Bentley
- Department of Plant Sciences, University of Oxford, Oxford OX1 3RB, United Kingdom
| | - Jordi Paps
- Department of Zoology, University of Oxford, Oxford OX1 3PS, United Kingdom
| | - Holger B Kramer
- Department of Physiology, Anatomy, and Genetics, University of Oxford, Oxford OX1 3QX, United Kingdom; and
| | - Joongoo Lee
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Oxford OX1 3TA, United Kingdom
| | - WeiShen Aik
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Oxford OX1 3TA, United Kingdom
| | - Hwanho Choi
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Oxford OX1 3TA, United Kingdom
| | - Steinar M Paulsen
- Department of Plant Sciences, University of Oxford, Oxford OX1 3RB, United Kingdom
| | - Lesley A H Bowman
- Department of Pathology, University of Oxford, Oxford OX1 3RE, United Kingdom
| | - Nikita D Loik
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Oxford OX1 3TA, United Kingdom
| | - Shoichiro Horita
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Oxford OX1 3TA, United Kingdom; Department of Physiology, Anatomy, and Genetics, University of Oxford, Oxford OX1 3QX, United Kingdom; and
| | - Chia-hua Ho
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Oxford OX1 3TA, United Kingdom
| | - Nadia J Kershaw
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Oxford OX1 3TA, United Kingdom
| | - Christoph M Tang
- Department of Pathology, University of Oxford, Oxford OX1 3RE, United Kingdom
| | - Timothy D W Claridge
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Oxford OX1 3TA, United Kingdom
| | - Gail M Preston
- Department of Plant Sciences, University of Oxford, Oxford OX1 3RB, United Kingdom
| | - Michael A McDonough
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Oxford OX1 3TA, United Kingdom
| | - Christopher J Schofield
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Oxford OX1 3TA, United Kingdom;
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Jantsch J, Schödel J. Hypoxia and hypoxia-inducible factors in myeloid cell-driven host defense and tissue homeostasis. Immunobiology 2014; 220:305-14. [PMID: 25439732 DOI: 10.1016/j.imbio.2014.09.009] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2014] [Revised: 08/01/2014] [Accepted: 09/05/2014] [Indexed: 02/08/2023]
Abstract
The impact of tissue oxygenation and hypoxia on immune cells has been recognized as a major determinant of host defense and tissue homeostasis. In this review, we will summarize the available data on tissue oxygenation in inflamed and infected tissue and the effect of low tissue oxygenation on myeloid cell function. Furthermore, we will highlight effects of the master regulators of the cellular hypoxic response, hypoxia-inducible transcription factors (HIF), in myeloid cells in antimicrobial defense and tissue homeostasis.
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Affiliation(s)
- Jonathan Jantsch
- Institut für Klinische Mikrobiologie und Hygiene, Universitätsklinikum Regensburg, Germany; Mikrobiologisches Institut - Klinische Mikrobiologie, Immunologie und Hygiene, Universitätsklinikum Erlangen und Friedrich-Alexander Universität (FAU) Erlangen-Nürnberg, Erlangen, Germany.
| | - Johannes Schödel
- Medizinische Klinik 4, Universitätsklinikum Erlangen und Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg, Erlangen, Germany; Translational Research Center, Universitätsklinikum Erlangen und Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg, Erlangen, Germany.
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Yao M, Wang X, Tang Y, Zhang W, Cui B, Liu Q, Xing L. Dicer mediating the expression of miR-143 and miR-155 regulates hexokinase II associated cellular response to hypoxia. Am J Physiol Lung Cell Mol Physiol 2014; 307:L829-37. [PMID: 25172909 DOI: 10.1152/ajplung.00081.2014] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Lung alveolar epithelial cells are exposed to hypoxia under a variety of physiological and pathological conditions. It has been shown recently that miR-143, which can directly target the key glycolytic enzyme hexokinase II (HK2), may be regulated by miR-155. We investigated whether microRNAs contribute to the cellular glycolysis in response to hypoxia. Using the A549 cells, we found that the expression of Dicer is decreased under hypoxia. When Dicer was knocked down with small-interfering RNA (siRNA), pre-miR143 was increased and mature miR-143 was decreased as that in hypoxia, indicating that reduction of Dicer is responsible for the change of miR-143 under hypoxia. Interestingly, both hypoxia and knockdown of Dicer resulted in miR-155 and pre-miR-155 expression increases. We also examined the expression of HK2 and glucose metabolism in the cells. Both HK2 mRNA and protein were increased under hypoxia, which is accompanied by an increase of glucose uptake and production of lactate. The same alterations were found with siRNA Dicer knockdown. Moreover, transfection with anti-miR-143 also led to a HK2 production and an increase of glucose uptake and lactate production, whereas anti-miR-155 had opposite effects. The miR-143 and anti-miR-155 transfection resulted in a significant cell apoptosis. The expression of Dicer was decreased with HK2 accumulating in mouse lung tissues under hypoxia identified by immunohistochemistry. The changes of miR-143 and miR-155 were similar to those in A549 cells. Our data demonstrate that Dicer regulation of miRNAs promotes HK2 activation and glycolysis, which might protect the cell from hypoxic damage and enter into an adaptive process.
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Affiliation(s)
- Mengying Yao
- Department of Severe Respiratory Diseases, the First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Xinhua Wang
- Department of Oncology, the First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Ying Tang
- Shanghai Navy Medical Institute, Shanghai, China
| | - Weihong Zhang
- Department of Anatomy, Nursing College of Zhengzhou University, Zhengzhou, China; and
| | - Bing Cui
- Center of Kidney Diseases, the First Affiliated Hospital, Henan College of Traditional Chinese Medicine, Zhengzhou, China
| | - Qiuhong Liu
- Department of Severe Respiratory Diseases, the First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Lihua Xing
- Department of Severe Respiratory Diseases, the First Affiliated Hospital of Zhengzhou University, Zhengzhou, China;
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Iannitti RG, Casagrande A, De Luca A, Cunha C, Sorci G, Riuzzi F, Borghi M, Galosi C, Massi-Benedetti C, Oury TD, Cariani L, Russo M, Porcaro L, Colombo C, Majo F, Lucidi V, Fiscarelli E, Ricciotti G, Lass-Flörl C, Ratclif L, Esposito A, De Benedictis FM, Donato R, Carvalho A, Romani L. Hypoxia promotes danger-mediated inflammation via receptor for advanced glycation end products in cystic fibrosis. Am J Respir Crit Care Med 2014; 188:1338-50. [PMID: 24127697 DOI: 10.1164/rccm.201305-0986oc] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
RATIONALE Hypoxia regulates the inflammatory-antiinflammatory balance by the receptor for advanced glycation end products (RAGE), a versatile sensor of damage-associated molecular patterns. The multiligand nature of RAGE places this receptor in the midst of chronic inflammatory diseases. OBJECTIVES To characterize the impact of the hypoxia-RAGE pathway on pathogenic airway inflammation preventing effective pathogen clearance in cystic fibrosis (CF) and elucidate the potential role of this danger signal in pathogenesis and therapy of lung inflammation. METHODS We used in vivo and in vitro models to study the impact of hypoxia on RAGE expression and activity in human and murine CF, the nature of the RAGE ligand, and the impact of RAGE on lung inflammation and antimicrobial resistance in fungal and bacterial pneumonia. MEASUREMENTS AND MAIN RESULTS Sustained expression of RAGE and its ligand S100B was observed in murine lung and human epithelial cells and exerted a proximal role in promoting inflammation in murine and human CF, as revealed by functional studies and analysis of the genetic variability of AGER in patients with CF. Both hypoxia and infections contributed to the sustained activation of the S100B-RAGE pathway, being RAGE up-regulated by hypoxia and S100B by infection by Toll-like receptors. Inhibiting the RAGE pathway in vivo with soluble (s) RAGE reduced pathogen load and inflammation in experimental CF, whereas sRAGE production was defective in patients with CF. CONCLUSIONS A causal link between hyperactivation of RAGE and inflammation in CF has been observed, such that targeting pathogenic inflammation alleviated inflammation in CF and measurement of sRAGE levels could be a useful biomarker for RAGE-dependent inflammation in patients with CF.
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Affiliation(s)
- Rossana G Iannitti
- 1 Department of Experimental Medicine and Biochemical Sciences, University of Perugia, Perugia, Italy
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Yoon GS, Dong C, Gao N, Kumar A, Standiford TJ, Yu FSX. Interferon regulatory factor-1 in flagellin-induced reprogramming: potential protective role of CXCL10 in cornea innate defense against Pseudomonas aeruginosa infection. Invest Ophthalmol Vis Sci 2013; 54:7510-21. [PMID: 24130180 DOI: 10.1167/iovs.13-12453] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
PURPOSE We previously showed that pre-exposure of the cornea to Toll-like receptor (TLR)5 ligand flagellin induces strong protective innate defense against microbial pathogens and hypothesized that flagellin modulates gene expression at the transcriptional levels. Thus, we sought to determine the role of one transcription factor, interferon regulatory factor (IRF1), and its target gene CXCL10 therein. METHODS Superarray was used to identify transcription factors differentially expressed in Pseudomonas aeruginosa-challenged human corneal epithelial cells (CECs) with or without flagellin pretreatment. The expression of CXCL10, IRF1, LI-8(CXCL2), and IFNγ was determined by PCR, immunohistochemistry, Western/dot blotting, and/or ELISA. IRF1 knockout mice, CXCL10 and IFNγ neutralization, and NK cell depletion were used to define in vivo regulation and function of CXCL10. The severity of P. aeruginosa was assessed using clinical scoring, slit-lamp microscopy, bacterial counting, polymorphonuclear leukocytes (PMN) infiltration, and macrophage inflammatory protein 2/Chemokine (C-X-C motif) ligand 2 (MIP-2/CXCL2) expression. RESULTS Flagellin pretreatment drastically affected P. aeruginosa-induced IRF1 expression in human CECs. However, flagellin pretreatment augmented the P. aeruginosa-induced expression of Irf1 and its target gene Cxcl10 in B6 mouse corneas. Irf1 deficiency reduced infection-triggered CXCL10 expression, increased keratitis severity, and attenuated flagellin-elicited protection compared to values in wild-type (WT) controls. CXCL10 neutralization in the cornea of WT mice displayed pathogenesis similar to that of IRF1⁻/⁻ mice. IFNγ receptor neutralization and NK cell depletion prevented flagellin-augmented IRF1 and CXCL10 expression and increased the susceptibility to P. aeruginosa infection in mouse corneas. CONCLUSIONS IRF1 plays a role in the corneal innate immune response by regulating CXCL10 expression. IFNγ-producing NK cells augment the epithelial expression of IRF1 and CXCL10 and thus contribute to the innate defense of the cornea against P. aeruginosa infection.
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Affiliation(s)
- Gi Sang Yoon
- Department of Anatomy and Cell Biology, Kresge Eye Institute, Wayne State University, Detroit, Michigan
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Berger EA, McClellan SA, Vistisen KS, Hazlett LD. HIF-1α is essential for effective PMN bacterial killing, antimicrobial peptide production and apoptosis in Pseudomonas aeruginosa keratitis. PLoS Pathog 2013; 9:e1003457. [PMID: 23874197 PMCID: PMC3715414 DOI: 10.1371/journal.ppat.1003457] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2013] [Accepted: 05/08/2013] [Indexed: 12/28/2022] Open
Abstract
Hypoxia-inducible factor (HIF)-1α, is a transcription factor that controls energy metabolism and angiogenesis under hypoxic conditions, and a potent regulator of innate immunity. The studies described herein examined the role of HIF-1α in disease resolution in BALB/c (resistant, cornea heals) mice after ocular infection with Pseudomonas (P.) aeruginosa. Furthermore, the current studies focused on the neutrophil (PMN), the predominant cell infiltrate in keratitis. Using both siRNA and an antagonist (17-DMAG), the role of HIF-1α was assessed in P. aeruginosa-infected BALB/c mice. Clinical score and slit lamp photography indicated HIF-1α inhibition exacerbated disease and corneal destruction. Real time RT-PCR, immunohistochemistry, ELISA, Greiss and MPO assays, bacterial load, intracellular killing, phagocytosis and apoptosis assays further tested the regulatory role of HIF-1α. Despite increased pro-inflammatory cytokine expression and increased MPO levels after knocking down HIF-1α expression, in vivo studies revealed a decrease in NO production and higher bacterial load. In vitro studies using PMN provided evidence that although inhibition of HIF-1α did not affect phagocytosis, both bacterial killing and apoptosis were significantly affected, as was production of antimicrobial peptides. Overall, data provide evidence that inhibition of HIF-1α converts a normally resistant disease response to susceptible (corneal thinning and perforation) after induction of bacterial keratitis. Although this inhibition does not appear to affect PMN transmigration or phagocytosis, both in vivo and in vitro approaches indicate that the transcriptional factor is essential for effective bacterial killing, apoptosis and antimicrobial peptide production.
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Affiliation(s)
- Elizabeth A. Berger
- Department of Anatomy and Cell Biology, Wayne State University School of Medicine, Detroit, Michigan, United States of America
| | - Sharon A. McClellan
- Department of Anatomy and Cell Biology, Wayne State University School of Medicine, Detroit, Michigan, United States of America
| | - Kerry S. Vistisen
- Department of Anatomy and Cell Biology, Wayne State University School of Medicine, Detroit, Michigan, United States of America
| | - Linda D. Hazlett
- Department of Anatomy and Cell Biology, Wayne State University School of Medicine, Detroit, Michigan, United States of America
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Schaible B, McClean S, Selfridge A, Broquet A, Asehnoune K, Taylor CT, Schaffer K. Hypoxia modulates infection of epithelial cells by Pseudomonas aeruginosa. PLoS One 2013; 8:e56491. [PMID: 23418576 PMCID: PMC3572047 DOI: 10.1371/journal.pone.0056491] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2012] [Accepted: 01/10/2013] [Indexed: 11/18/2022] Open
Abstract
Pseudomonas aeruginosa (P. aeruginosa) is an opportunistic pathogen commonly associated with lung and wound infections. Hypoxia is a frequent feature of the microenvironment of infected tissues which induces the expression of genes associated with innate immunity and inflammation in host cells primarily through the activation of the hypoxia-inducible factor (HIF) and Nuclear factor kappaB (NF-κB) pathways which are regulated by oxygen-dependent prolyl-hydroxylases. Hypoxia also affects virulence and antibiotic resistance in bacterial pathogens. However, less is known about the impact of hypoxia on host-pathogen interactions such as bacterial adhesion and infection. In the current study, we demonstrate that hypoxia decreases the internalization of P. aeruginosa into cultured epithelial cells resulting in decreased host cell death. This response can also be elicited by the hydroxylase inhibitor Dimethyloxallyl Glycine (DMOG). Reducing HIF-2α expression or Rho kinase activity diminished the effects of hypoxia on P. aeruginosa infection. Furthermore, in an in vivo pneumonia infection model, application of DMOG 48 h before infection with P. aeruginosa significantly reduced mortality. Thus, hypoxia reduces P. aeruginosa internalization into epithelial cells and pharmacologic manipulation of the host pathways involved may represent new therapeutic targets in the treatment of P. aeruginosa infection.
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Affiliation(s)
- Bettina Schaible
- UCD School of Medicine and Medical Science and The Conway Institute, University College Dublin, Dublin, Ireland
- School of Pharmacy, Queens's University, Belfast, United Kingdom
| | | | - Andrew Selfridge
- UCD School of Medicine and Medical Science and The Conway Institute, University College Dublin, Dublin, Ireland
| | - Alexis Broquet
- Laboratoire UPRES EA 3826 «Thérapeutiques cliniques et expérimentales des infections», Faculté de médecine, Université de Nantes, Nantes, France
| | - Karim Asehnoune
- Laboratoire UPRES EA 3826 «Thérapeutiques cliniques et expérimentales des infections», Faculté de médecine, Université de Nantes, Nantes, France
- Centre Hospitalier Universitaire de Nantes, Service anesthésie réanimation chirurgicale, Hôtel Dieu-HME, Nantes, France
| | - Cormac T. Taylor
- UCD School of Medicine and Medical Science and The Conway Institute, University College Dublin, Dublin, Ireland
| | - Kirsten Schaffer
- Department of Microbiology, St. Vincent's University Hospital, Dublin, Ireland
- * E-mail:
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Abstract
The pathogenic fungus Cryptococcus neoformans exhibits a striking propensity to cause central nervous system (CNS) disease in people with HIV/AIDS. Given that cryptococcal infections are generally initiated by pulmonary colonization, dissemination requires that the fungus withstand phagocytic killing, cross the alveolar-capillary interface in the lung, survive in the circulatory system and breach the blood-brain barrier. We know little about the molecular mechanisms underlying dissemination, but there is a rapidly growing list of mutants that fail to cause CNS disease. These mutants reveal a remarkable diversity of functions and therefore illustrate the complexity of the cryptococcal-host interaction. The challenge now is to extend the analysis of these mutants to acquire a detailed understanding of each step in dissemination.
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