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Ocampo D, Damon LJ, Sanford L, Holtzen SE, Jones T, Allen MA, Dowell RD, Palmer AE. Cellular zinc status alters chromatin accessibility and binding of p53 to DNA. Life Sci Alliance 2024; 7:e202402638. [PMID: 38969365 PMCID: PMC11231577 DOI: 10.26508/lsa.202402638] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2024] [Revised: 06/20/2024] [Accepted: 06/21/2024] [Indexed: 07/07/2024] Open
Abstract
Zn2+ is an essential metal required by approximately 850 human transcription factors. How these proteins acquire their essential Zn2+ cofactor and whether they are sensitive to changes in the labile Zn2+ pool in cells remain open questions. Using ATAC-seq to profile regions of accessible chromatin coupled with transcription factor enrichment analysis, we examined how increases and decreases in the labile zinc pool affect chromatin accessibility and transcription factor enrichment. We found 685 transcription factor motifs were differentially enriched, corresponding to 507 unique transcription factors. The pattern of perturbation and the types of transcription factors were notably different at promoters versus intergenic regions, with zinc-finger transcription factors strongly enriched in intergenic regions in elevated Zn2+ To test whether ATAC-seq and transcription factor enrichment analysis predictions correlate with changes in transcription factor binding, we used ChIP-qPCR to profile six p53 binding sites. We found that for five of the six targets, p53 binding correlates with the local accessibility determined by ATAC-seq. These results demonstrate that changes in labile zinc alter chromatin accessibility and transcription factor binding to DNA.
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Affiliation(s)
- Daniel Ocampo
- Department of Biochemistry, University of Colorado, Boulder, CO, USA
| | - Leah J Damon
- Department of Biochemistry, University of Colorado, Boulder, CO, USA
| | - Lynn Sanford
- Department of Molecular, Cellular, Developmental Biology, University of Colorado, Boulder, CO, USA
| | - Samuel E Holtzen
- Department of Molecular, Cellular, Developmental Biology, University of Colorado, Boulder, CO, USA
| | - Taylor Jones
- Department of Molecular, Cellular, Developmental Biology, University of Colorado, Boulder, CO, USA
| | - Mary A Allen
- Department of Molecular, Cellular, Developmental Biology, University of Colorado, Boulder, CO, USA
- BioFrontiers Institute, University of Colorado, Boulder, CO, USA
| | - Robin D Dowell
- Department of Molecular, Cellular, Developmental Biology, University of Colorado, Boulder, CO, USA
- BioFrontiers Institute, University of Colorado, Boulder, CO, USA
| | - Amy E Palmer
- Department of Biochemistry, University of Colorado, Boulder, CO, USA
- BioFrontiers Institute, University of Colorado, Boulder, CO, USA
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Damon LJ, Ocampo D, Sanford L, Jones T, Allen MA, Dowell RD, Palmer AE. Cellular zinc status alters chromatin accessibility and binding of transcription factor p53 to genomic sites. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.20.567954. [PMID: 38045276 PMCID: PMC10690171 DOI: 10.1101/2023.11.20.567954] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/05/2023]
Abstract
Zinc (Zn2+) is an essential metal required by approximately 2500 proteins. Nearly half of these proteins act on DNA, including > 850 human transcription factors, polymerases, DNA damage response factors, and proteins involved in chromatin architecture. How these proteins acquire their essential Zn2+ cofactor and whether they are sensitive to changes in the labile Zn2+ pool in cells remain open questions. Here, we examine how changes in the labile Zn2+ pool affect chromatin accessibility and transcription factor binding to DNA. We observed both increases and decreases in accessibility in different chromatin regions via ATAC-seq upon treating MCF10A cells with elevated Zn2+ or the Zn2+-specific chelator tris(2-pyridylmethyl)amine (TPA). Transcription factor enrichment analysis was used to correlate changes in chromatin accessibility with transcription factor motifs, revealing 477 transcription factor motifs that were differentially enriched upon Zn2+ perturbation. 186 of these transcription factor motifs were enriched in Zn2+ and depleted in TPA, and the majority correspond to Zn2+ finger transcription factors. We selected TP53 as a candidate to examine how changes in motif enrichment correlate with changes in transcription factor occupancy by ChIP-qPCR. Using publicly available ChIP-seq and nascent transcription datasets, we narrowed the 50,000+ ATAC-seq peaks to 2164 TP53 targets and subsequently selected 6 high-probability TP53 binding sites for testing. ChIP-qPCR revealed that for 5 of the 6 targets, TP53 binding correlates with the local accessibility determined by ATAC-seq. These results demonstrate that changes in labile zinc directly alter chromatin accessibility and transcription factor binding to DNA.
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Affiliation(s)
- Leah J. Damon
- Department of Biochemistry, University of Colorado, Boulder, CO 80303
| | - Daniel Ocampo
- Department of Biochemistry, University of Colorado, Boulder, CO 80303
| | - Lynn Sanford
- Department of Molecular, Cellular, Developmental Biology, University of Colorado, Boulder, 80309
| | - Taylor Jones
- Department of Molecular, Cellular, Developmental Biology, University of Colorado, Boulder, 80309
| | - Mary A. Allen
- Department of Molecular, Cellular, Developmental Biology, University of Colorado, Boulder, 80309
- BioFrontiers Institute, University of Colorado, Boulder, CO 80303
| | - Robin D. Dowell
- Department of Molecular, Cellular, Developmental Biology, University of Colorado, Boulder, 80309
- BioFrontiers Institute, University of Colorado, Boulder, CO 80303
| | - Amy E. Palmer
- Department of Biochemistry, University of Colorado, Boulder, CO 80303
- BioFrontiers Institute, University of Colorado, Boulder, CO 80303
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Karlebach G, Steinhaus R, Danis D, Devoucoux M, Anczuków O, Sheynkman G, Seelow D, Robinson PN. Alternative splicing is coupled to gene expression in a subset of variably expressed genes. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.06.13.544742. [PMID: 37398049 PMCID: PMC10312658 DOI: 10.1101/2023.06.13.544742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/04/2023]
Abstract
Numerous factors regulate alternative splicing of human genes at a co-transcriptional level. However, how alternative splicing depends on the regulation of gene expression is poorly understood. We leveraged data from the Genotype-Tissue Expression (GTEx) project to show a significant association of gene expression and splicing for 6874 (4.9%) of 141,043 exons in 1106 (13.3%) of 8314 genes with substantially variable expression in ten GTEx tissues. About half of these exons demonstrate higher inclusion with higher gene expression, and half demonstrate higher exclusion, with the observed direction of coupling being highly consistent across different tissues and in external datasets. The exons differ with respect to sequence characteristics, enriched sequence motifs, RNA polymerase II binding, and inferred transcription rate of downstream introns. The exons were enriched for hundreds of isoform-specific Gene Ontology annotations, suggesting that the coupling of expression and alternative splicing described here may provide an important gene regulatory mechanism that might be used in a variety of biological contexts. In particular, higher inclusion exons could play an important role during cell division.
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Affiliation(s)
- Guy Karlebach
- The Jackson Laboratory for Genomic Medicine, Farmington, CT 06032, USA
| | - Robin Steinhaus
- Exploratory Diagnostic Sciences, Berlin Institute of Health, 10117 Berlin, Germany
- Institute of Medical Genetics and Human Genetics, Charité - Universitätsmedizin Berlin, corporate member of Freie Universitat Berlin and Humboldt-Universität zu Berlin, 13353 10117 Berlin, Germany
| | - Daniel Danis
- The Jackson Laboratory for Genomic Medicine, Farmington, CT 06032, USA
| | - Maeva Devoucoux
- The Jackson Laboratory for Genomic Medicine, Farmington, CT 06032, USA
| | - Olga Anczuków
- The Jackson Laboratory for Genomic Medicine, Farmington, CT 06032, USA
- Department of Genetics and Genome Sciences, UConn Health, Farmington, CT 06032, USA
- Institute for Systems Genomics, University of Connecticut, Farmington, CT 06032, USA
| | - Gloria Sheynkman
- Department of Molecular Physiology and Biological Physics, University of Virginia School of Medicine, Charlottesville, VA 22903, USA
| | - Dominik Seelow
- Exploratory Diagnostic Sciences, Berlin Institute of Health, 10117 Berlin, Germany
- Institute of Medical Genetics and Human Genetics, Charité - Universitätsmedizin Berlin, corporate member of Freie Universitat Berlin and Humboldt-Universität zu Berlin, 13353 10117 Berlin, Germany
| | - Peter N Robinson
- The Jackson Laboratory for Genomic Medicine, Farmington, CT 06032, USA
- Department of Molecular Physiology and Biological Physics, University of Virginia School of Medicine, Charlottesville, VA 22903, USA
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Noah TL, Worden CP, Rebuli ME, Jaspers I. The Effects of Wildfire Smoke on Asthma and Allergy. Curr Allergy Asthma Rep 2023; 23:375-387. [PMID: 37171670 PMCID: PMC10176314 DOI: 10.1007/s11882-023-01090-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/01/2023] [Indexed: 05/13/2023]
Abstract
PURPOSE OF REVIEW To review the recent literature on the effects of wildfire smoke (WFS) exposure on asthma and allergic disease, and on potential mechanisms of disease. RECENT FINDINGS Spatiotemporal modeling and increased ground-level monitoring data are allowing a more detailed picture of the health effects of WFS exposure to emerge, especially with regard to asthma. There is also epidemiologic and some experimental evidence to suggest that WFS exposure increases allergic predisposition and upper airway or sinonasal disease, though much of the literature in this area is focused more generally on PM2.5 and is not specific for WFS. Experimental evidence for mechanisms includes disruption of epithelial integrity with downstream effects on inflammatory or immune pathways, but experimental models to date have not consistently reflected human disease in this area. Exposure to WFS has an acute detrimental effect on asthma. Potential mechanisms are suggested by in vitro and animal studies.
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Affiliation(s)
- Terry L Noah
- Department of Pediatrics, University of North Carolina at Chapel Hill, 260 Macnider Building, 333 S. Columbia St., Chapel Hill, NC, 27599, USA.
- Center for Environmental Medicine, Asthma and Lung Biology, University of North Carolina at Chapel Hill, Chapel Hill, USA.
| | - Cameron P Worden
- Department of Otolaryngology/Head & Neck Surgery, University of North Carolina at Chapel Hill, Chapel Hill, USA
- Center for Environmental Medicine, Asthma and Lung Biology, University of North Carolina at Chapel Hill, Chapel Hill, USA
| | - Meghan E Rebuli
- Department of Pediatrics, University of North Carolina at Chapel Hill, 260 Macnider Building, 333 S. Columbia St., Chapel Hill, NC, 27599, USA
- Center for Environmental Medicine, Asthma and Lung Biology, University of North Carolina at Chapel Hill, Chapel Hill, USA
| | - Ilona Jaspers
- Department of Pediatrics, University of North Carolina at Chapel Hill, 260 Macnider Building, 333 S. Columbia St., Chapel Hill, NC, 27599, USA
- Center for Environmental Medicine, Asthma and Lung Biology, University of North Carolina at Chapel Hill, Chapel Hill, USA
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Perez MF, Yurieva M, Poddutoori S, Mortensen EM, Crotty Alexander LE, Williams A. Transcriptomic responses in the blood and sputum of cigarette smokers compared to e-cigarette vapers. Respir Res 2023; 24:134. [PMID: 37208747 PMCID: PMC10196320 DOI: 10.1186/s12931-023-02438-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Accepted: 04/27/2023] [Indexed: 05/21/2023] Open
Abstract
RATIONALE Electronic (e)-cigarettes are popular among youth and cigarette smokers attempting to quit. Studies to date have focused on the utility of e-cigarettes as a smoking cessation tool, but the biological effects are largely unknown. OBJECTIVES To identify transcriptomic differences in the blood and sputum of e-cigarette users compared to conventional cigarettes smokers and healthy controls and describe biological pathways affected by these tobacco products. METHODS Cross-sectional analysis of whole blood and sputum RNA-sequencing data from 8 smokers, 9 e-cigarette users (e-cigs) and 4 controls. Weighted gene co-network analysis (WGCNA) identified gene module associations. Ingenuity Pathway Analysis (IPA) identified canonical pathways associated with tobacco products. MAIN RESULTS In blood, a three-group comparison showed 16 differentially expressed genes (DEGs); pair-wise comparison showed 7 DEGs between e-cigs and controls, 35 DEGs between smokers and controls, and 13 DEGs between smokers and e-cigs. In sputum, 438 DEGs were in the three-group comparison. In pair-wise comparisons, there were 2 DEGs between e-cigs and controls, 270 DEGs between smokers and controls, and 468 DEGs between smokers and e-cigs. Only 2 genes in the smokers vs. control comparison overlapped between blood and sputum. Most gene modules identified through WGCNA associated with tobacco product exposures also were associated with cotinine and exhaled CO levels. IPA showed more canonical pathways altered by conventional cigarette smoking than by e-cigarette use. CONCLUSION Cigarette smoking and e-cigarette use led to transcriptomic changes in both blood and sputum. However, conventional cigarettes induced much stronger transcriptomic responses in both compartments.
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Affiliation(s)
- Mario F Perez
- Department of Pulmonary, Critical Care and Sleep Medicine, University of Connecticut School of Medicine, Farmington, CT, USA.
| | - Marina Yurieva
- The Jackson Laboratory for Genomic Medicine, Farmington, CT, USA
| | | | - Eric M Mortensen
- Department of Pulmonary, Critical Care and Sleep Medicine, University of Connecticut School of Medicine, Farmington, CT, USA
| | - Laura E Crotty Alexander
- Division of Pulmonary Critical Care, Department of Medicine, University of California San Diego, San Diego, CA, USA
| | - Adam Williams
- The Jackson Laboratory for Genomic Medicine, Farmington, CT, USA
- Division of Allergy and Immunology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
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Despréaux P, Jeanton C, Desaulle D, Al Zallouha M, Verdin A, Momas I, Achard S. Innovative graph analysis method to assess gene expression modulation after fine particles exposures of 3D human airway epithelia. ENVIRONMENTAL RESEARCH 2023; 221:115296. [PMID: 36642119 DOI: 10.1016/j.envres.2023.115296] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Revised: 12/27/2022] [Accepted: 01/11/2023] [Indexed: 06/17/2023]
Abstract
Environmental particles have dramatic consequences for health, especially for the most vulnerable people, such as asthmatics. To better understand the impact on gene expression modulation of fine particles (PM2.5-0.3) from different emission sources, a 3D-airway model, a human bronchial epithelium (MucilAir-HF™) reconstructed from primary cells from healthy (EpiH) or asthmatic (EpiA) donors, was used. Repeated air-liquid exposures were performed, and epithelia were sacrificed to extract RNAs and assess gene expression. Data were analyzed according to the emission sources, physiological status, and exposure doses using a recent model consisting in a graph analysis on pairwise expression ratio. The results were compared with those from the classical ΔΔCt method. The graph analysis method proved to have better statistical properties than the classical ΔΔCt method and demonstrated that repeated PM2.5-0.3 exposures induced a dose-dependent up-regulation of the metabolic gene (CYP1B1) and a down-regulation of the inflammation gene (CXCL10). These modulations were greater for "industrial" than for "urban traffic" fine particles, and the effects were found to be greater after exposure of EpiA than EpiH, thus emphasizing the importance of the epithelium's physiological status in sensitivity to particles. Our study is original in terms of the experimental conditions and the graphical statistical analysis model established. The results highlight the importance of particle chemistry on the modulation of cellular and molecular responses, which may vary according to the individual's vulnerability.
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Affiliation(s)
- Philomène Despréaux
- Université Paris Cité, Faculté de Pharmacie, CRESS INSERM UMR 1153, équipe HERA (Health Environmental Risk Assessment), Paris, France
| | - Capucine Jeanton
- Université Paris Cité, Faculté de Pharmacie, CRESS INSERM UMR 1153, équipe HERA (Health Environmental Risk Assessment), Paris, France
| | - Dorota Desaulle
- Université Paris Cité, Faculté de Pharmacie, UR 7537 - BioSTM (Biostatistique, Traitement et Modélisation des données biologiques), Paris, France
| | - Margueritta Al Zallouha
- Université Paris Cité, Faculté de Pharmacie, CRESS INSERM UMR 1153, équipe HERA (Health Environmental Risk Assessment), Paris, France
| | - Anthony Verdin
- Université du Littoral Côte d'Opale, Unité de Chimie Environnementale et Interactions sur le Vivant (UCEIV) UR4492, SFR Condorcet CNRS 3417, Dunkerque, France
| | - Isabelle Momas
- Université Paris Cité, Faculté de Pharmacie, CRESS INSERM UMR 1153, équipe HERA (Health Environmental Risk Assessment), Paris, France
| | - Sophie Achard
- Université Paris Cité, Faculté de Pharmacie, CRESS INSERM UMR 1153, équipe HERA (Health Environmental Risk Assessment), Paris, France.
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Pesticides and Their Impairing Effects on Epithelial Barrier Integrity, Dysbiosis, Disruption of the AhR Signaling Pathway and Development of Immune-Mediated Inflammatory Diseases. Int J Mol Sci 2022; 23:ijms232012402. [PMID: 36293259 PMCID: PMC9604036 DOI: 10.3390/ijms232012402] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 10/04/2022] [Accepted: 10/12/2022] [Indexed: 11/16/2022] Open
Abstract
The environmental and occupational risk we confront from agricultural chemicals increases as their presence in natural habitats rises to hazardous levels, building a major part of the exposome. This is of particular concern in low- and middle-income countries, such as Brazil, known as a leading producer of agricultural commodities and consumer of pesticides. As long as public policies continue to encourage the indiscriminate use of pesticides and governments continue to support this strategy instead of endorsing sustainable agricultural alternatives, the environmental burden that damages epithelial barriers will continue to grow. Chronic exposure to environmental contaminants in early life can affect crucial barrier tissue, such as skin epithelium, airways, and intestine, causing increased permeability, leaking, dysbiosis, and inflammation, with serious implications for metabolism and homeostasis. This vicious cycle of exposure to environmental factors and the consequent damage to the epithelial barrier has been associated with an increase in immune-mediated chronic inflammatory diseases. Understanding how the harmful effects of pesticides on the epithelial barrier impact cellular interactions mediated by endogenous sensors that coordinate a successful immune system represents a crucial challenge. In line with the epithelial barrier hypothesis, this narrative review reports the available evidence on the effects of pesticides on epithelial barrier integrity, dysbiosis, AhR signaling, and the consequent development of immune-mediated inflammatory diseases.
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Gupta A, Sasse SK, Berman R, Gruca MA, Dowell RD, Chu HW, Downey GP, Gerber AN. Integrated genomics approaches identify transcriptional mediators and epigenetic responses to Afghan desert particulate matter in small airway epithelial cells. Physiol Genomics 2022; 54:389-401. [PMID: 36062885 PMCID: PMC9550581 DOI: 10.1152/physiolgenomics.00063.2022] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Revised: 08/15/2022] [Accepted: 08/29/2022] [Indexed: 01/14/2023] Open
Abstract
Military Deployment to Southwest Asia and Afghanistan and exposure to toxic airborne particulates have been associated with an increased risk of developing respiratory disease, collectively termed deployment-related respiratory diseases (DRRDs). Our knowledge about how particulates mediate respiratory disease is limited, precluding the appropriate recognition or management. Central to this limitation is the lack of understanding of how exposures translate into dysregulated cell identity with dysregulated transcriptional programs. The small airway epithelium is involved in both the pathobiology of DRRD and fine particulate matter deposition. To characterize small airway epithelial cell epigenetic and transcriptional responses to Afghan desert particulate matter (APM) and investigate the functional interactions of transcription factors that mediate these responses, we applied two genomics assays, the assay for transposase accessible chromatin with sequencing (ATAC-seq) and Precision Run-on sequencing (PRO-seq). We identified activity changes in a series of transcriptional pathways as candidate regulators of susceptibility to subsequent insults, including signal-dependent pathways, such as loss of cytochrome P450 or P53/P63, and lineage-determining transcription factors, such as GRHL2 loss or TEAD3 activation. We further demonstrated that TEAD3 activation was unique to APM exposure despite similar inflammatory responses when compared with wood smoke particle exposure and that P53/P63 program loss was uniquely positioned at the intersection of signal-dependent and lineage-determining transcriptional programs. Our results establish the utility of an integrated genomics approach in characterizing responses to exposures and identifying genomic targets for the advanced investigation of the pathogenesis of DRRD.
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Affiliation(s)
- Arnav Gupta
- Department of Medicine, National Jewish Health, Denver, Colorado
| | - Sarah K Sasse
- Department of Medicine, National Jewish Health, Denver, Colorado
| | - Reena Berman
- Department of Medicine, National Jewish Health, Denver, Colorado
| | - Margaret A Gruca
- Biofrontiers Institute, University of Colorado Boulder, Boulder, Colorado
| | - Robin D Dowell
- Biofrontiers Institute, University of Colorado Boulder, Boulder, Colorado
| | - Hong Wei Chu
- Department of Medicine, National Jewish Health, Denver, Colorado
| | - Gregory P Downey
- Department of Medicine, National Jewish Health, Denver, Colorado
| | - Anthony N Gerber
- Department of Medicine, National Jewish Health, Denver, Colorado
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El Kharbili M, Aviszus K, Sasse SK, Zhao X, Serban KA, Majka SM, Gerber AN, Gally F. Macrophage programming is regulated by a cooperative interaction between fatty acid binding protein 5 and peroxisome proliferator-activated receptor γ. FASEB J 2022; 36:e22300. [PMID: 35436029 PMCID: PMC9320869 DOI: 10.1096/fj.202200128r] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Revised: 03/07/2022] [Accepted: 03/24/2022] [Indexed: 11/11/2022]
Abstract
Resolution of inflammation is an active process that is tightly regulated to achieve repair and tissue homeostasis. In the absence of resolution, persistent inflammation underlies the pathogenesis of chronic lung disease such as chronic obstructive pulmonary disease (COPD) with recurrent exacerbations. Over the course of inflammation, macrophage programming transitions from pro-inflammatory to pro-resolving, which is in part regulated by the nuclear receptor Peroxisome Proliferator-Activated Receptor γ (PPARγ). Our previous work demonstrated an association between Fatty Acid Binding Protein 5 (FABP5) expression and PPARγ activity in peripheral blood mononuclear cells of healthy and COPD patients. However, a role for FABP5 in macrophage programming has not been examined. Here, using a combination of in vitro and in vivo approaches, we demonstrate that FABP5 is necessary for PPARγ activation. In turn, PPARγ acts directly to increase FABP5 expression in primary human alveolar macrophages. We further illustrate that lack of FABP5 expression promotes a pro-inflammatory macrophage programming with increased secretion of pro-inflammatory cytokines and increased chromatin accessibility for pro-inflammatory transcription factors (e.g., NF-κB and MAPK). And finally, real-time cell metabolic analysis using the Seahorse technology shows an inhibition of oxidative phosphorylation in FABP5-deficient macrophages. Taken together, our data indicate that FABP5 and PPARγ reciprocally regulate each other's expression and function, consistent with a novel positive feedback loop between the two factors that mediates macrophage pro-resolving programming. Our studies highlight the importance of defining targets and regulatory mechanisms that control the resolution of inflammation and may serve to inform novel interventional strategies directed towards COPD.
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Affiliation(s)
- Manale El Kharbili
- Department of Immunology and Genomic MedicineNational Jewish HealthDenverColoradoUSA
| | - Katja Aviszus
- Department of Immunology and Genomic MedicineNational Jewish HealthDenverColoradoUSA
| | - Sarah K. Sasse
- Department of MedicineNational Jewish HealthDenverColoradoUSA
| | - Xiaoyun Zhao
- Department of Immunology and Genomic MedicineNational Jewish HealthDenverColoradoUSA
| | - Karina A. Serban
- Department of MedicineNational Jewish HealthDenverColoradoUSA
- Department of MedicineUniversity of ColoradoAuroraColoradoUSA
| | - Susan M. Majka
- Department of Immunology and Genomic MedicineNational Jewish HealthDenverColoradoUSA
- Department of MedicineNational Jewish HealthDenverColoradoUSA
- Department of MedicineUniversity of ColoradoAuroraColoradoUSA
| | - Anthony N. Gerber
- Department of Immunology and Genomic MedicineNational Jewish HealthDenverColoradoUSA
- Department of MedicineNational Jewish HealthDenverColoradoUSA
- Department of MedicineUniversity of ColoradoAuroraColoradoUSA
| | - Fabienne Gally
- Department of Immunology and Genomic MedicineNational Jewish HealthDenverColoradoUSA
- Department of MedicineUniversity of ColoradoAuroraColoradoUSA
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