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Bai X, Gao J, Guan X, Narum DE, Fornis LB, Griffith DE, Gao B, Sandhaus RA, Huang H, Chan ED. Analysis of alpha-1-antitrypsin (AAT)-regulated, glucocorticoid receptor-dependent genes in macrophages reveals a novel host defense function of AAT. Physiol Rep 2024; 12:e16124. [PMID: 39016119 PMCID: PMC11252833 DOI: 10.14814/phy2.16124] [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: 04/01/2024] [Revised: 06/14/2024] [Accepted: 06/14/2024] [Indexed: 07/18/2024] Open
Abstract
Alpha-1-antitrypsin (AAT) plays a homeostatic role in attenuating excessive inflammation and augmenting host defense against microbes. We demonstrated previously that AAT binds to the glucocorticoid receptor (GR) resulting in significant anti-inflammatory and antimycobacterial consequences in macrophages. Our current investigation aims to uncover AAT-regulated genes that rely on GR in macrophages. We incubated control THP-1 cells (THP-1control) and THP-1 cells knocked down for GR (THP-1GR-KD) with AAT, performed bulk RNA sequencing, and analyzed the findings. In THP-1control cells, AAT significantly upregulated 408 genes and downregulated 376 genes. Comparing THP-1control and THP-1GR-KD cells, 125 (30.6%) of the AAT-upregulated genes and 154 (41.0%) of the AAT-downregulated genes were significantly dependent on GR. Among the AAT-upregulated, GR-dependent genes, CSF-2 that encodes for granulocyte-monocyte colony-stimulating factor (GM-CSF), known to be host-protective against nontuberculous mycobacteria, was strongly upregulated by AAT and dependent on GR. We further quantified the mRNA and protein of several AAT-upregulated, GR-dependent genes in macrophages and the mRNA of several AAT-downregulated, GR-dependent genes. We also discussed the function(s) of selected AAT-regulated, GR-dependent gene products largely in the context of mycobacterial infections. In conclusion, AAT regulated several genes that are dependent on GR and play roles in host immunity against mycobacteria.
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Affiliation(s)
- Xiyuan Bai
- Department of MedicineRocky Mountain Regional Veterans Affairs Medical CenterAuroraColoradoUSA
- Department of Academic AffairsNational Jewish HealthDenverColoradoUSA
- Division of Pulmonary Sciences and Critical Care MedicineUniversity of Colorado Anschutz Medical CampusAuroraColoradoUSA
| | - Junfeng Gao
- Department of Immunology and Genomic MedicineNational Jewish HealthDenverColoradoUSA
| | - Xiaoyu Guan
- Department of Biostatistics and InformaticsUniversity of Colorado School of Public Health Anschutz Medical CampusAuroraColoradoUSA
| | - Drew E. Narum
- Department of Academic AffairsNational Jewish HealthDenverColoradoUSA
| | | | - David E. Griffith
- Division of Pulmonary Sciences and Critical Care MedicineUniversity of Colorado Anschutz Medical CampusAuroraColoradoUSA
- Department of MedicineNational Jewish HealthDenverColoradoUSA
| | - Bifeng Gao
- Division of Pulmonary Sciences and Critical Care MedicineUniversity of Colorado Anschutz Medical CampusAuroraColoradoUSA
| | - Robert A. Sandhaus
- Division of Pulmonary Sciences and Critical Care MedicineUniversity of Colorado Anschutz Medical CampusAuroraColoradoUSA
- Department of MedicineNational Jewish HealthDenverColoradoUSA
| | - Hua Huang
- Department of Immunology and Genomic MedicineNational Jewish HealthDenverColoradoUSA
- Department of Immunology and MicrobiologyUniversity of Colorado School of MedicineAuroraColoradoUSA
| | - Edward D. Chan
- Department of MedicineRocky Mountain Regional Veterans Affairs Medical CenterAuroraColoradoUSA
- Department of Academic AffairsNational Jewish HealthDenverColoradoUSA
- Division of Pulmonary Sciences and Critical Care MedicineUniversity of Colorado Anschutz Medical CampusAuroraColoradoUSA
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2
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Lian GY, Wang QM, Mak TSK, Huang XR, Yu XQ, Lan HY. Disrupting Smad3 potentiates immunostimulatory function of NK cells against lung carcinoma by promoting GM-CSF production. Cell Mol Life Sci 2024; 81:262. [PMID: 38878186 DOI: 10.1007/s00018-024-05290-4] [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: 09/25/2023] [Revised: 04/28/2024] [Accepted: 05/23/2024] [Indexed: 06/29/2024]
Abstract
Through Smad3-dependent signalings, transforming growth factor-β (TGF-β) suppresses the development, maturation, cytokine productions and cytolytic functions of NK cells in cancer. Silencing Smad3 remarkably restores the cytotoxicity of NK-92 against cancer in TGF-β-rich microenvironment, but its effects on the immunoregulatory functions of NK cells remain obscure. In this study, we identified Smad3 functioned as a transcriptional repressor for CSF2 (GM-CSF) in NK cells. Therefore, disrupting Smad3 largely mitigated TGF-β-mediated suppression on GM-CSF production by NK cells. Furthermore, silencing GM-CSF in Smad3 knockout NK cells substantially impaired their anti-lung carcinoma effects. In-depth study demonstrated that NK-derived GM-CSF strengthened T cell immune responses by stimulating dendritic cell differentiation and M1 macrophage polarization. Meanwhile, NK-derived GM-CSF promoted the survival of neutrophils, which in turn facilitated the terminal maturation of NK cells, and subsequently boosted NK-cell mediated cytotoxicity against lung carcinoma. Thus, Smad3-silenced NK-92 (NK-92-S3KD) may serve as a promising immunoadjuvant therapy with clinical translational value given its robust cytotoxicity against malignant cells and immunostimulatory functions to reinforce the therapeutic effects of other immunotherapies.
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Affiliation(s)
- Guang-Yu Lian
- Guangdong-Hong Kong Joint Research Laboratory on Immunological and Genetic Kidney Diseases, Departments of Pathology and Nephrology, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, 510080, China
- Guangdong Cardiovascular Institute, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, 510080, China
- Department of Medicine & Therapeutics, and Li Ka Shing Institute of Health Sciences, The Chinese University of Hong Kong, Hong Kong SAR, China
| | - Qing-Ming Wang
- Department of Medicine & Therapeutics, and Li Ka Shing Institute of Health Sciences, The Chinese University of Hong Kong, Hong Kong SAR, China
- Department of Hematology, The Second Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, China
| | - Thomas Shiu-Kwong Mak
- Department of Medicine & Therapeutics, and Li Ka Shing Institute of Health Sciences, The Chinese University of Hong Kong, Hong Kong SAR, China
| | - Xiao-Ru Huang
- Guangdong-Hong Kong Joint Research Laboratory on Immunological and Genetic Kidney Diseases, Departments of Pathology and Nephrology, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, 510080, China
- Department of Medicine & Therapeutics, and Li Ka Shing Institute of Health Sciences, The Chinese University of Hong Kong, Hong Kong SAR, China
| | - Xue-Qing Yu
- Guangdong-Hong Kong Joint Research Laboratory on Immunological and Genetic Kidney Diseases, Departments of Pathology and Nephrology, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, 510080, China.
- Guangdong Cardiovascular Institute, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, 510080, China.
| | - Hui-Yao Lan
- Guangdong-Hong Kong Joint Research Laboratory on Immunological and Genetic Kidney Diseases, Departments of Pathology and Nephrology, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, 510080, China.
- Department of Medicine & Therapeutics, and Li Ka Shing Institute of Health Sciences, The Chinese University of Hong Kong, Hong Kong SAR, China.
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3
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Tang M, Yin Y, Wang W, Gong K, Dong J, Gao X, Li J, Fang L, Ma J, Hong Y, Li Z, Bi T, Zhang W, Liu W. Exploring the multifaceted effects of Interleukin-1 in lung cancer: From tumor development to immune modulation. Life Sci 2024; 342:122539. [PMID: 38423172 DOI: 10.1016/j.lfs.2024.122539] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Revised: 02/21/2024] [Accepted: 02/25/2024] [Indexed: 03/02/2024]
Abstract
Lung cancer, acknowledged as one of the most fatal cancers globally, faces limited treatment options on an international scale. The success of clinical treatment is impeded by challenges such as late diagnosis, restricted treatment alternatives, relapse, and the emergence of drug resistance. This predicament has led to a saturation point in lung cancer treatment, prompting a rapid shift in focus towards the tumor microenvironment (TME) as a pivotal area in cancer research. Within the TME, Interleukin-1 (IL-1) is abundantly present, originating from immune cells, tissue stromal cells, and tumor cells. IL-1's induction of pro-inflammatory mediators and chemokines establishes an inflammatory milieu influencing tumor occurrence, development, and the interaction between tumors and the host immune system. Notably, IL-1 expression in the TME exhibits characteristics such as staging, tissue specificity, and functional pluripotency. This comprehensive review aims to delve into the impact of IL-1 on lung cancer, encompassing aspects of occurrence, invasion, metastasis, immunosuppression, and immune surveillance. The ultimate goal is to propose a novel treatment approach, considering the intricate dynamics of IL-1 within the TME.
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Affiliation(s)
- Mingbo Tang
- Department of Thoracic Surgery, The First Hospital of Jilin University, Changchun, Jilin, 130021, China
| | - Yipeng Yin
- Department of Thoracic Surgery, The First Hospital of Jilin University, Changchun, Jilin, 130021, China
| | - Wei Wang
- Key Laboratory of Endocrine Glucose & Lipids Metabolism and Brain Aging, Ministry of Education, Department of Endocrinology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, Shandong 250021, China; Shandong Key Laboratory of Endocrinology and Lipid Metabolism, Jinan, Shandong 250021, China; Shandong Institute of Endocrine and Metabolic Diseases, Jinan, Shandong 250021, China; "Chuangxin China" Innovation Base of stem cell and Gene Therapy for endocrine Metabolic diseases, Jinan, Shandong 250021, China; Shandong Engineering Laboratory of Prevention and Control for Endocrine and Metabolic Diseases, Jinan, Shandong 250021, China; Shandong Engineering Research Center of Stem Cell and Gene Therapy for Endocrine and Metabolic Diseases, Jinan, Shandong 250021, China
| | - Kejian Gong
- Department of Thoracic Surgery, The First Hospital of Jilin University, Changchun, Jilin, 130021, China
| | - Junxue Dong
- Laboratory of Infection Oncology, Institute of Clinical Molecular Biology, Universitätsklinikum Schleswig-Holstein (UKSH), Christian Albrechts University of Kiel, Kiel, Germany
| | - Xinliang Gao
- Department of Thoracic Surgery, The First Hospital of Jilin University, Changchun, Jilin, 130021, China
| | - Jialin Li
- Department of Thoracic Surgery, The First Hospital of Jilin University, Changchun, Jilin, 130021, China
| | - Linan Fang
- Department of Thoracic Surgery, The First Hospital of Jilin University, Changchun, Jilin, 130021, China
| | - Jianzun Ma
- Department of Thoracic Surgery, The First Hospital of Jilin University, Changchun, Jilin, 130021, China
| | - Yang Hong
- Department of Thoracic Surgery, The First Hospital of Jilin University, Changchun, Jilin, 130021, China
| | - Zhiqin Li
- Department of Thoracic Surgery, The First Hospital of Jilin University, Changchun, Jilin, 130021, China
| | - Taiyu Bi
- Department of Thoracic Surgery, The First Hospital of Jilin University, Changchun, Jilin, 130021, China
| | - Wenyu Zhang
- Department of Thoracic Surgery, The First Hospital of Jilin University, Changchun, Jilin, 130021, China
| | - Wei Liu
- Department of Thoracic Surgery, The First Hospital of Jilin University, Changchun, Jilin, 130021, China.
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Cataldo Russomando A, Steinberg D, Gati I, Vogt Sionov R, Eliashar R, Friedman M, Gross M. Sinonasal Stent Coated with Sustained-Release Varnish of Mometasone Furoate Inhibits Pro-Inflammatory Cytokine Release from Macrophages: An In Vitro Study. Pharmaceutics 2023; 15:pharmaceutics15031015. [PMID: 36986875 PMCID: PMC10051169 DOI: 10.3390/pharmaceutics15031015] [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: 02/24/2023] [Revised: 03/16/2023] [Accepted: 03/20/2023] [Indexed: 03/30/2023] Open
Abstract
The aim of the study was to develop a sustained-release varnish (SRV) containing mometasone furoate (MMF) for sinonasal stents (SNS) to reduce mucosa inflammation in the sinonasal cavity. The SNS' segments coated with SRV-MMF or an SRV-placebo were incubated daily in a fresh DMEM at 37 °C for 20 days. The immunosuppressive activity of the collected DMEM supernatants was tested on the ability of mouse RAW 264.7 macrophages to secrete the cytokines' tumor necrosis factor α (TNFα) and interleukin (IL)-10 and IL-6 in response to lipopolysaccharide (LPS). The cytokine levels were determined by respective Enzyme-Linked Immunosorbent Assays (ELISAs). We found that the daily amount of MMF released from the coated SNS was sufficient to significantly inhibit LPS-induced IL-6 and IL-10 secretion from the macrophages up to days 14 and 17, respectively. SRV-MMF had, however, only a mild inhibitory effect on LPS-induced TNFα secretion as compared to the SRV-placebo-coated SNS. In conclusion, the coating of SNS with SRV-MMF provides a sustained delivery of MMF for at least 2 weeks, maintaining a level sufficient for inhibiting pro-inflammatory cytokine release. This technological platform is, therefore, expected to provide anti-inflammatory benefits during the postoperative healing period and may play a significant role in the future treatment of chronic rhinosinusitis.
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Affiliation(s)
- Alessandra Cataldo Russomando
- Department of Otolaryngology-Head and Neck Surgery, Hadassah Medical Center, Jerusalem 9112102, Israel
- The Biofilm Research Laboratory, The Institute of Biomedical and Oral Research (IBOR), The Faculty of Dental Medicine, Hebrew University of Jerusalem, Jerusalem 9112102, Israel
| | - Doron Steinberg
- The Biofilm Research Laboratory, The Institute of Biomedical and Oral Research (IBOR), The Faculty of Dental Medicine, Hebrew University of Jerusalem, Jerusalem 9112102, Israel
| | - Irith Gati
- Institute for Drug Research, School of Pharmacy, The Hebrew University of Jerusalem, Jerusalem 9112102, Israel
| | - Ronit Vogt Sionov
- The Biofilm Research Laboratory, The Institute of Biomedical and Oral Research (IBOR), The Faculty of Dental Medicine, Hebrew University of Jerusalem, Jerusalem 9112102, Israel
| | - Ron Eliashar
- Department of Otolaryngology-Head and Neck Surgery, Hadassah Medical Center, Jerusalem 9112102, Israel
- The Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem 9112102, Israel
| | - Michael Friedman
- Institute for Drug Research, School of Pharmacy, The Hebrew University of Jerusalem, Jerusalem 9112102, Israel
| | - Menachem Gross
- Department of Otolaryngology-Head and Neck Surgery, Hadassah Medical Center, Jerusalem 9112102, Israel
- The Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem 9112102, Israel
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5
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Bansal A, Mostafa MM, Kooi C, Sasse SK, Michi AN, Shah SV, Leigh R, Gerber AN, Newton R. Interplay between nuclear factor-κB, p38 MAPK and glucocorticoid receptor signaling synergistically induces functional TLR2 in lung epithelial cells. J Biol Chem 2022; 298:101747. [PMID: 35189144 PMCID: PMC8942839 DOI: 10.1016/j.jbc.2022.101747] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 02/11/2022] [Accepted: 02/12/2022] [Indexed: 12/05/2022] Open
Abstract
While glucocorticoids act via the glucocorticoid receptor (GR; NR3C1) to reduce the expression of many inflammatory genes, repression is not an invariable outcome. Here, we explore synergy occurring between synthetic glucocorticoids (dexamethasone and budesonide) and proinflammatory cytokines (IL1B and TNF) on the expression of the toll-like receptor 2 (TLR2). This effect is observed in epithelial cell lines and both undifferentiated and differentiated primary human bronchial epithelial cells (pHBECs). In A549 cells, IL1B-plus-glucocorticoid–induced TLR2 expression required nuclear factor (NF)-κB and GR. Likewise, in A549 cells, BEAS-2B cells, and pHBECs, chromatin immunoprecipitation identified GR- and NF-κB/p65-binding regions ∼32 kb (R1) and ∼7.3 kb (R2) upstream of the TLR2 gene. Treatment of BEAS-2B cells with TNF or/and dexamethasone followed by global run-on sequencing confirmed transcriptional activity at these regions. Furthermore, cloning R1 or R2 into luciferase reporters revealed transcriptional activation by budesonide or IL1B, respectively, while R1+R2 juxtaposition enabled synergistic activation by IL1B and budesonide. In addition, small-molecule inhibitors and siRNA knockdown showed p38α MAPK to negatively regulate both IL1B-induced TLR2 expression and R1+R2 reporter activity. Finally, agonism of IL1B-plus-dexamethasone–induced TLR2 in A549 cells and pHBECs stimulated NF-κB- and interferon regulatory factor-dependent reporter activity and chemokine release. We conclude that glucocorticoid-plus-cytokine-driven synergy at TLR2 involves GR and NF-κB acting via specific enhancer regions, which combined with the inhibition of p38α MAPK promotes TLR2 expression. Subsequent inflammatory effects that occur following TLR2 agonism may be pertinent in severe neutrophilic asthma or chronic obstructive pulmonary disease, where glucocorticoid-based therapies are less efficacious.
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Affiliation(s)
- Akanksha Bansal
- Department of Physiology & Pharmacology and Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Mahmoud M Mostafa
- Department of Physiology & Pharmacology and Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Cora Kooi
- Department of Medicine and Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada
| | - Sarah K Sasse
- Department of Medicine, National Jewish Health, Denver, Colorado, USA
| | - Aubrey N Michi
- Department of Physiology & Pharmacology and Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Suharsh V Shah
- Department of Physiology & Pharmacology and Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Richard Leigh
- Department of Physiology & Pharmacology and Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada; Department of Medicine and Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada
| | - Anthony N Gerber
- Department of Medicine, National Jewish Health, Denver, Colorado, USA; Department of Medicine, University of Colorado, Aurora, Colorado, USA
| | - Robert Newton
- Department of Physiology & Pharmacology and Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.
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CMAHP promotes metastasis by reducing ubiquitination of Snail and inducing angiogenesis via GM-CSF overexpression in gastric cancer. Oncogene 2022; 41:159-172. [PMID: 34716430 DOI: 10.1038/s41388-021-02087-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 10/15/2021] [Accepted: 10/19/2021] [Indexed: 12/18/2022]
Abstract
Pseudogenes are generally considered "junk" DNA or "genomic fossils" generated during the evolution process that lack biological activity. However, accumulating reports indicate that pseudogenes have biological functions critical for cancer development. Experiments from the current study showed marked overexpression of the cytidine monophospho-N-acetylneuraminic acid hydroxylase pseudogene (CMAHP) in gastric cancer, which was associated with poor overall survival. However, the mechanisms underlying the activity of CMAHP in tumor development are largely unknown. Gene Set Enrichment Analysis (GSEA) revealed that CMAHP-correlated genes are significantly involved in epithelial-mesenchymal transition (EMT) and angiogenesis. Functional studies further confirmed that CMAHP mediates metastasis and angiogenesis in vitro and in vivo. Furthermore, CMAHP promoted cancer cell migration, invasion, and metastasis through Snail overexpression, which decreased ubiquitination mediated by NF-κB signaling. Angiogenesis is known to be induced by granulocyte-macrophage colony-stimulating factor (GM-CSF) stimulation. CMAHP increased GM-CSF transactivation via promoting direct binding of c-Jun to the -1981/-1975 region of the GM-CSF promoter. Notably, CMAHP interacts with Histone H1.4 promoting histone acetylation to enhance c-Jun and RelA (p65) expression. Our collective findings provide novel evidence that CMAHP contributes to tumor progression and modulates metastasis and angiogenesis in gastric cancer.
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Busada JT, Peterson KN, Khadka S, Xu X, Oakley RH, Cook DN, Cidlowski JA. Glucocorticoids and Androgens Protect From Gastric Metaplasia by Suppressing Group 2 Innate Lymphoid Cell Activation. Gastroenterology 2021; 161:637-652.e4. [PMID: 33971182 PMCID: PMC8328958 DOI: 10.1053/j.gastro.2021.04.075] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/21/2020] [Revised: 04/13/2021] [Accepted: 04/27/2021] [Indexed: 02/07/2023]
Abstract
BACKGROUND & AIMS The immune compartment is critical for maintaining tissue homeostasis. A weak immune response increases susceptibility to infection, but immune hyperactivation causes tissue damage, and chronic inflammation may lead to cancer development. In the stomach, inflammation damages the gastric glands and drives the development of potentially preneoplastic metaplasia. Glucocorticoids are potent anti-inflammatory steroid hormones that are required to suppress gastric inflammation and metaplasia. However, these hormones function differently in males and females. Here, we investigate the impact of sex on the regulation of gastric inflammation. METHODS Endogenous glucocorticoids and male sex hormones were removed from mice using adrenalectomy and castration, respectively. Mice were treated with 5α-dihydrotestosterone (DHT) to test the effects of androgens on regulating gastric inflammation. Single-cell RNA sequencing of gastric leukocytes was used to identify the leukocyte populations that were the direct targets of androgen signaling. Type 2 innate lymphoid cells (ILC2s) were depleted by treatment with CD90.2 antibodies. RESULTS We show that adrenalectomized female mice develop spontaneous gastric inflammation and spasmolytic polypeptide-expressing metaplasia (SPEM) but that the stomachs of adrenalectomized male mice remain quantitatively normal. Simultaneous depletion of glucocorticoids and sex hormones abolished the male-protective effects and triggered spontaneous pathogenic gastric inflammation and SPEM. Treatment of female mice with DHT prevented gastric inflammation and SPEM development when administered concurrent with adrenalectomy and also reversed the pathology when administered after disease onset. Single-cell RNAseq of gastric leukocytes revealed that ILC2s expressed abundant levels of both the glucocorticoid receptor (Gr) and androgen receptor (Ar). We demonstrated that DHT treatment potently suppressed the expression of the proinflammatory cytokines Il13 and Csf2 by ILC2s. Moreover, ILC2 depletion protected the stomach from SPEM development. CONCLUSIONS Here, we report a novel mechanism by which glucocorticoids and androgens exert overlapping effects to regulate gastric inflammation. Androgen signaling within ILC2s prevents their pathogenic activation by suppressing the transcription of proinflammatory cytokines. This work revealed a critical role for sex hormones in regulating gastric inflammation and metaplasia.
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MESH Headings
- Adrenalectomy
- Androgens/pharmacology
- Animals
- Anti-Inflammatory Agents/pharmacology
- Cellular Microenvironment
- Dihydrotestosterone/pharmacology
- Disease Models, Animal
- Disease Susceptibility
- Female
- Gastric Mucosa/drug effects
- Gastric Mucosa/immunology
- Gastric Mucosa/metabolism
- Gastric Mucosa/pathology
- Gastritis, Atrophic/immunology
- Gastritis, Atrophic/metabolism
- Gastritis, Atrophic/pathology
- Gastritis, Atrophic/prevention & control
- Glucocorticoids/metabolism
- Gonadal Steroid Hormones/metabolism
- Granulocyte-Macrophage Colony-Stimulating Factor/genetics
- Granulocyte-Macrophage Colony-Stimulating Factor/metabolism
- Homeodomain Proteins/genetics
- Homeodomain Proteins/metabolism
- Intercellular Signaling Peptides and Proteins/metabolism
- Interleukin-13/genetics
- Interleukin-13/metabolism
- Interleukin-33/genetics
- Interleukin-33/metabolism
- Lymphocytes/drug effects
- Lymphocytes/immunology
- Lymphocytes/metabolism
- Male
- Metaplasia
- Mice, Inbred C57BL
- Orchiectomy
- Receptors, Androgen/genetics
- Receptors, Androgen/metabolism
- Receptors, Glucocorticoid/genetics
- Receptors, Glucocorticoid/metabolism
- Sex Factors
- Signal Transduction
- Thy-1 Antigens/genetics
- Thy-1 Antigens/metabolism
- Mice
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Affiliation(s)
- Jonathan T Busada
- Molecular Endocrinology Group, Signal Transduction Laboratory, North Carolina; Department of Microbiology, Immunology and Cell Biology, West Virginia University School of Medicine, Morgantown, West Virginia.
| | - Kylie N Peterson
- Molecular Endocrinology Group, Signal Transduction Laboratory, North Carolina
| | - Stuti Khadka
- Department of Microbiology, Immunology and Cell Biology, West Virginia University School of Medicine, Morgantown, West Virginia
| | - Xiaojiang Xu
- Integrative Bioinformatics Support Group, Epigenetics and Stem Cell Biology Laboratory, North Carolina
| | - Robert H Oakley
- Molecular Endocrinology Group, Signal Transduction Laboratory, North Carolina
| | - Donald N Cook
- Immunogenetics Group, Immunity, Inflammation, and Disease Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, North Carolina
| | - John A Cidlowski
- Molecular Endocrinology Group, Signal Transduction Laboratory, North Carolina.
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8
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Manley GCA, Parker LC, Zhang Y. Emerging Regulatory Roles of Dual-Specificity Phosphatases in Inflammatory Airway Disease. Int J Mol Sci 2019; 20:E678. [PMID: 30764493 PMCID: PMC6387402 DOI: 10.3390/ijms20030678] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Revised: 01/31/2019] [Accepted: 02/01/2019] [Indexed: 12/16/2022] Open
Abstract
Inflammatory airway disease, such as asthma and chronic obstructive pulmonary disease (COPD), is a major health burden worldwide. These diseases cause large numbers of deaths each year due to airway obstruction, which is exacerbated by respiratory viral infection. The inflammatory response in the airway is mediated in part through the MAPK pathways: p38, JNK and ERK. These pathways also have roles in interferon production, viral replication, mucus production, and T cell responses, all of which are important processes in inflammatory airway disease. Dual-specificity phosphatases (DUSPs) are known to regulate the MAPKs, and roles for this family of proteins in the pathogenesis of airway disease are emerging. This review summarizes the function of DUSPs in regulation of cytokine expression, mucin production, and viral replication in the airway. The central role of DUSPs in T cell responses, including T cell activation, differentiation, and proliferation, will also be highlighted. In addition, the importance of this protein family in the lung, and the necessity of further investigation into their roles in airway disease, will be discussed.
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Affiliation(s)
- Grace C A Manley
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117545, Singapore.
- Immunology Programme, Life Science Institute, National University of Singapore, Singapore 117597, Singapore.
| | - Lisa C Parker
- Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, Sheffield S10 2RX, UK.
| | - Yongliang Zhang
- Department of Microbiology and Immunology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117545, Singapore.
- Immunology Programme, Life Science Institute, National University of Singapore, Singapore 117597, Singapore.
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9
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Mostafa MM, Rider CF, Shah S, Traves SL, Gordon PMK, Miller-Larsson A, Leigh R, Newton R. Glucocorticoid-driven transcriptomes in human airway epithelial cells: commonalities, differences and functional insight from cell lines and primary cells. BMC Med Genomics 2019; 12:29. [PMID: 30704470 PMCID: PMC6357449 DOI: 10.1186/s12920-018-0467-2] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Accepted: 12/21/2018] [Indexed: 12/16/2022] Open
Abstract
Background Glucocorticoids act on the glucocorticoid receptor (GR; NR3C1) to resolve inflammation and, as inhaled corticosteroids (ICS), are the cornerstone of treatment for asthma. However, reduced efficacy in severe disease or exacerbations indicates a need to improve ICS actions. Methods Glucocorticoid-driven transcriptomes were compared using PrimeView microarrays between primary human bronchial epithelial (HBE) cells and the model cell lines, pulmonary type II A549 and bronchial epithelial BEAS-2B cells. Results In BEAS-2B cells, budesonide induced (≥2-fold, P ≤ 0.05) or, in a more delayed fashion, repressed (≤0.5-fold, P ≤ 0.05) the expression of 63, 133, 240, and 257 or 15, 56, 236, and 344 mRNAs at 1, 2, 6, and 18 h, respectively. Within the early-induced mRNAs were multiple transcriptional activators and repressors, thereby providing mechanisms for the subsequent modulation of gene expression. Using the above criteria, 17 (BCL6, BIRC3, CEBPD, ERRFI1, FBXL16, FKBP5, GADD45B, IRS2, KLF9, PDK4, PER1, RGCC, RGS2, SEC14L2, SLC16A12, TFCP2L1, TSC22D3) induced and 8 (ARL4C, FLRT2, IER3, IL11, PLAUR, SEMA3A, SLC4A7, SOX9) repressed mRNAs were common between A549, BEAS-2B and HBE cells at 6 h. As absolute gene expression change showed greater commonality, lowering the cut-off (≥1.25 or ≤ 0.8-fold) within these groups produced 93 induced and 82 repressed genes in common. Since large changes in few mRNAs and/or small changes in many mRNAs may drive function, gene ontology (GO)/pathway analyses were performed using both stringency criteria. Budesonide-induced genes showed GO term enrichment for positive and negative regulation of transcription, signaling, proliferation, apoptosis, and movement, as well as FOXO and PI3K-Akt signaling pathways. Repressed genes were enriched for inflammatory signaling pathways (TNF, NF-κB) and GO terms for cytokine activity, chemotaxis and cell signaling. Reduced growth factor expression and effects on proliferation and apoptosis were highlighted. Conclusions While glucocorticoids repress mRNAs associated with inflammation, prior induction of transcriptional activators and repressors may explain longer-term responses to these agents. Furthermore, positive and negative effects on signaling, proliferation, migration and apoptosis were revealed. Since many such gene expression changes occurred in human airways post-ICS inhalation, the effects observed in cell lines and primary HBE cells in vitro may be relevant to ICS in vivo. Electronic supplementary material The online version of this article (10.1186/s12920-018-0467-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Mahmoud M Mostafa
- Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada.,Cardiovascular and Respiratory Sciences graduate program, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Christopher F Rider
- Department of Medicine, Vancouver General Hospital, University of British Columbia, Vancouver, British Columbia, Canada
| | - Suharsh Shah
- Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada
| | - Suzanne L Traves
- Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada
| | - Paul M K Gordon
- Centre for Health Genomics and Informatics, University of Calgary, Calgary, Alberta, Canada
| | | | - Richard Leigh
- Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada
| | - Robert Newton
- Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada.
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10
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Souffriau J, Eggermont M, Van Ryckeghem S, Van Looveren K, Van Wyngene L, Van Hamme E, Vuylsteke M, Beyaert R, De Bosscher K, Libert C. A screening assay for Selective Dimerizing Glucocorticoid Receptor Agonists and Modulators (SEDIGRAM) that are effective against acute inflammation. Sci Rep 2018; 8:12894. [PMID: 30150712 PMCID: PMC6110732 DOI: 10.1038/s41598-018-31150-w] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Accepted: 08/13/2018] [Indexed: 02/07/2023] Open
Abstract
It has been suggested that glucocorticoid receptor (GR) agonists that promote GR homodimerization more than standard glucocorticoids such as Dexamethasone could be more effective anti-inflammatory molecules against acute and life-threatening inflammatory conditions. To test this hypothesis, we set up a screening pipeline aimed at discovering such Selective Dimerizing GR Agonists and Modulators (SEDIGRAM). The pipeline consists of a reporter gene assay based on a palindromic glucocorticoid responsive element (GRE). This assay represents GR dimerization in human A549 lung epithelial cells. In the pipeline, this is followed by analysis of endogenous GRE-driven gene expression, a FRET assay confirming dimerization, and monitoring of in vitro and in vivo anti-inflammatory activity. In a proof of principle experiment, starting from seven candidate compounds, we identified two potentially interesting compounds (Cortivazol and AZD2906) that confer strong protection in a mouse model of aggressive TNF-induced lethal inflammation. A screening pipeline for SEDIGRAM may assist the search for compounds that promote GR dimerization and limit overwhelming acute inflammatory responses.
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Affiliation(s)
- Jolien Souffriau
- Center for Inflammation Research, VIB, Ghent, Belgium.,Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
| | - Melanie Eggermont
- Center for Inflammation Research, VIB, Ghent, Belgium.,Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
| | - Sara Van Ryckeghem
- Center for Inflammation Research, VIB, Ghent, Belgium.,Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
| | - Kelly Van Looveren
- Center for Inflammation Research, VIB, Ghent, Belgium.,Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
| | - Lise Van Wyngene
- Center for Inflammation Research, VIB, Ghent, Belgium.,Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
| | - Evelien Van Hamme
- Bio Imaging Core, Center for Inflammation Research, VIB, Ghent, Belgium
| | | | - Rudi Beyaert
- Center for Inflammation Research, VIB, Ghent, Belgium.,Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
| | - Karolien De Bosscher
- Receptor Research Laboratories, Nuclear Receptor Lab, Center for Medical Biotechnology Center, VIB, Ghent, Belgium.,Department of Biochemistry, Ghent University, Ghent, Belgium
| | - Claude Libert
- Center for Inflammation Research, VIB, Ghent, Belgium. .,Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium.
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11
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Jin X, Liu L, Zhang Y, Xiang Y, Yin G, Lu Y, Shi L, Dong J, Shen C. Advanced Glycation End Products Enhance Murine Monocyte Proliferation in Bone Marrow and Prime Them into an Inflammatory Phenotype through MAPK Signaling. J Diabetes Res 2018; 2018:2527406. [PMID: 29765986 PMCID: PMC5885396 DOI: 10.1155/2018/2527406] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/09/2017] [Revised: 11/28/2017] [Accepted: 01/04/2018] [Indexed: 02/07/2023] Open
Abstract
OBJECTIVE Increased monocytes, particularly the inflammatory subset, are associated with accelerated atherosclerosis in diabetes through thus far incompletely defined mechanisms. The present study tested the hypothesis that advanced glycation end products (AGEs) promote bone marrow monocytes to proliferate and drive them into an inflammatory phenotype. METHODS AND RESULTS In vivo, AGEs (25 mg/kg i.p. for 7 days) increased proportions of CD115+ monocytes and the inflammatory subset, the CD115+Ly6Chigh cells, in murine bone marrow (flow cytometry analysis (FCM)), and enhanced gene expression of proinflammatory cytokines (IL-1β and TNF-α) but only slightly upregulated mRNA expression of anti-inflammatory cytokine (IL-10) (real-time PCR) in monocytes. In vitro, when the monocytes were treated with different dosages of AGEs (50, 150, and 300 μg/mL), we found that proliferation (CCK8) but not apoptosis (FCM) of the monocytes was induced; the mRNA expressions of proinflammatory cytokines (IL-1β and TNF-α) and GM-CSF were upregulated in a dose-dependent manner while mRNA levels of IL-10 and M-CSF were changed much less in monocytes (real-time PCR). Furthermore, AGEs (300 μg/mL) significantly enhanced the expression of Ki67 in monocytes (immunofluorescence staining (IF)), and this dose of AGEs markedly increased secretion of GM-CSF but not that of M-CSF (ELISA). For a pathway study, the monocytes were stimulated by 300 μg/mL AGEs for different periods of time (0, 15, 30, and 120 min) and the activation of the MAPK pathway was tested (FCM); the results showed the p38 and ERK pathways were activated but not JNK signaling. Pretreatment with an inhibitor of p38 (SB203580) or ERK (U0126) attenuated AGE-induced gene expression of proinflammatory cytokines and GM-CSF (real-time PCR), as well as reversing AGE-induced Ki67 expression (IF). CONCLUSIONS AGEs promote bone marrow monocytes to proliferate and drive them into an inflammatory phenotype through p38 and ERK activation.
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Affiliation(s)
- Xian Jin
- Department of Cardiology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China
| | - Liang Liu
- Department of Cardiology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China
- Department of Cardiology, Xin Hua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Yaping Zhang
- Department of Cardiology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China
| | - Yin Xiang
- Department of Cardiology, Xin Hua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Guizhi Yin
- Department of Cardiology, Minhang Hospital, Fudan University, Shanghai, China
| | - Yi Lu
- Department of Cardiology, Minhang Hospital, Fudan University, Shanghai, China
| | - Ludong Shi
- Department of Cardiology, Minhang Hospital, Fudan University, Shanghai, China
| | - Jian Dong
- Department of Cardiology, Minhang Hospital, Fudan University, Shanghai, China
| | - Chengxing Shen
- Department of Cardiology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China
- Department of Cardiology, Xin Hua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
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12
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Yang TC, Chang PY, Kuo TL, Lu SC. Electronegative L5-LDL induces the production of G-CSF and GM-CSF in human macrophages through LOX-1 involving NF-κB and ERK2 activation. Atherosclerosis 2017; 267:1-9. [PMID: 29078142 DOI: 10.1016/j.atherosclerosis.2017.10.016] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2017] [Revised: 09/30/2017] [Accepted: 10/12/2017] [Indexed: 12/17/2022]
Abstract
BACKGROUND AND AIMS Circulating levels of granulocyte colony-stimulating factor (G-CSF) and granulocyte macrophage colony-stimulating factor (GM-CSF) are associated with the severity of acute myocardial infarction (AMI). However, what causes increases in G-CSF and GM-CSF is unclear. In this study, we investigated whether L5-low-density lipoprotein (LDL), a mildly oxidized LDL from AMI, can induce G-CSF and GM-CSF production in human macrophages. METHODS L1-LDL and L5-LDL were isolated through anion-exchange chromatography from AMI plasma. Human macrophages derived from THP-1 and peripheral blood mononuclear cells were treated with L1-LDL, L5-LDL, or copper-oxidized LDL (Cu-oxLDL) and G-CSF and GM-CSF protein levels in the medium were determined. In addition, the effects of L5-LDL on G-CSF and GM-CSF production were tested in lectin-type oxidized LDL receptor-1 (LOX-1), CD36, extracellular signal-regulated kinase (ERK) 1, and ERK2 knockdown THP-1 macrophages. RESULTS L5-LDL but not L1-LDL or Cu-oxLDL significantly induced production of G-CSF and GM-CSF in macrophages. In vitro oxidation of L1-LDL and L5-LDL altered their ability to induce G-CSF and GM-CSF, suggesting that the degree of oxidation is critical for the effects. Knockdown and antibody neutralization experiments suggested that the effects were caused by LOX-1. In addition, nuclear factor (NF)-κB and ERK1/2 inhibition resulted in marked reductions of L5-LDL-induced G-CSF and GM-CSF production. Moreover, knockdown of ERK2, but not ERK1, hindered L5-LDL-induced G-CSF and GM-CSF production. CONCLUSIONS The results indicate that L5-LDL, a naturally occurring mild oxidized LDL, induced G-CSF and GM-CSF production in human macrophages through LOX-1, ERK2, and NF-κB dependent pathways.
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Affiliation(s)
- Tzu-Ching Yang
- Department of Biochemistry and Molecular Biology, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Po-Yuan Chang
- Cardiovascular Center and Division of Cardiology, Department of Internal Medicine, National Taiwan University College of Medicine, Taipei, Taiwan.
| | - Tzu-Ling Kuo
- Department of Biochemistry and Molecular Biology, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Shao-Chun Lu
- Department of Biochemistry and Molecular Biology, National Taiwan University College of Medicine, Taipei, Taiwan.
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13
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Newton R, Shah S, Altonsy MO, Gerber AN. Glucocorticoid and cytokine crosstalk: Feedback, feedforward, and co-regulatory interactions determine repression or resistance. J Biol Chem 2017; 292:7163-7172. [PMID: 28283576 DOI: 10.1074/jbc.r117.777318] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Inflammatory signals induce feedback and feedforward systems that provide temporal control. Although glucocorticoids can repress inflammatory gene expression, glucocorticoid receptor recruitment increases expression of negative feedback and feedforward regulators, including the phosphatase, DUSP1, the ubiquitin-modifying enzyme, TNFAIP3, or the mRNA-destabilizing protein, ZFP36. Moreover, glucocorticoid receptor cooperativity with factors, including nuclear factor-κB (NF-κB), may enhance regulator expression to promote repression. Conversely, MAPKs, which are inhibited by glucocorticoids, provide feedforward control to limit expression of the transcription factor IRF1, and the chemokine, CXCL10. We propose that modulation of feedback and feedforward control can determine repression or resistance of inflammatory gene expression toglucocorticoid.
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Affiliation(s)
- Robert Newton
- From the Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, University of Calgary, Alberta T2N 4Z6, Canada,
| | - Suharsh Shah
- the Arnie Charbonneau Cancer Institute, Department of Oncology, University of Calgary, Alberta T2N 4Z6, Canada
| | - Mohammed O Altonsy
- From the Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, University of Calgary, Alberta T2N 4Z6, Canada.,the Faculty of Science, Sohag University, Sohag 82524, Egypt, and
| | - Antony N Gerber
- the Department of Medicine, National Jewish Health, Denver, Colorado 80206
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14
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Newton R, Giembycz MA. Understanding how long-acting β 2 -adrenoceptor agonists enhance the clinical efficacy of inhaled corticosteroids in asthma - an update. Br J Pharmacol 2016; 173:3405-3430. [PMID: 27646470 DOI: 10.1111/bph.13628] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Revised: 08/19/2016] [Accepted: 08/21/2016] [Indexed: 12/18/2022] Open
Abstract
In moderate-to-severe asthma, adding an inhaled long-acting β2 -adenoceptor agonist (LABA) to an inhaled corticosteroid (ICS) provides better disease control than simply increasing the dose of ICS. Acting on the glucocorticoid receptor (GR, gene NR3C1), ICSs promote anti-inflammatory/anti-asthma gene expression. In vitro, LABAs synergistically enhance the maximal expression of many glucocorticoid-induced genes. Other genes, including dual-specificity phosphatase 1(DUSP1) in human airways smooth muscle (ASM) and epithelial cells, are up-regulated additively by both drug classes. Synergy may also occur for LABA-induced genes, as illustrated by the bronchoprotective gene, regulator of G-protein signalling 2 (RGS2) in ASM. Such effects cannot be produced by either drug alone and may explain the therapeutic efficacy of ICS/LABA combination therapies. While the molecular basis of synergy remains unclear, mechanistic interpretations must accommodate gene-specific regulation. We explore the concept that each glucocorticoid-induced gene is an independent signal transducer optimally activated by a specific, ligand-directed, GR conformation. In addition to explaining partial agonism, this realization provides opportunities to identify novel GR ligands that exhibit gene expression bias. Translating this into improved therapeutic ratios requires consideration of GR density in target tissues and further understanding of gene function. Similarly, the ability of a LABA to interact with a glucocorticoid may be suboptimal due to low β2 -adrenoceptor density or biased β2 -adrenoceptor signalling. Strategies to overcome these limitations include adding-on a phosphodiesterase inhibitor and using agonists of other Gs-coupled receptors. In all cases, the rational design of ICS/LABA, and derivative, combination therapies requires functional knowledge of induced (and repressed) genes for therapeutic benefit to be maximized.
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Affiliation(s)
- Robert Newton
- Department of Cell Biology and Anatomy, Airways Inflammation Research Group, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Mark A Giembycz
- Department of Physiology and Pharmacology, Airways Inflammation Research Group, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
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15
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Shah S, King EM, Mostafa MM, Altonsy MO, Newton R. DUSP1 Maintains IRF1 and Leads to Increased Expression of IRF1-dependent Genes: A MECHANISM PROMOTING GLUCOCORTICOID INSENSITIVITY. J Biol Chem 2016; 291:21802-21816. [PMID: 27551049 DOI: 10.1074/jbc.m116.728964] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2016] [Revised: 08/19/2016] [Indexed: 11/06/2022] Open
Abstract
Although the mitogen-activated protein kinase (MAPK) phosphatase, DUSP1, mediates dexamethasone-induced repression of MAPKs, 14 of 46 interleukin-1β (IL1B)-induced mRNAs were significantly enhanced by DUSP1 overexpression in pulmonary A549 cells. These include the interferon regulatory factor, IRF1, and the chemokine, CXCL10. Of these, DUSP1-enhanced mRNAs, 10 including CXCL10, were IRF1-dependent. MAPK inhibitors and DUSP1 overexpression prolonged IRF1 expression by elevating transcription and increasing IRF1 mRNA and protein stability. Conversely, DUSP1 silencing increased IL1B-induced MAPK phosphorylation while significantly reducing IRF1 protein expression at 4 h. This confirms a regulatory network whereby DUSP1 switches off MAPKs to maintain IRF1 expression. There was no repression of IRF1 expression by dexamethasone in primary human bronchial epithelial cells, and in A549 cells IL1B-induced IRF1 protein was only modestly and transiently repressed. Although dexamethasone did not repress IL1B-induced IRF1 protein expression at 4-6 h, silencing of IL1B plus dexamethasone-induced DUSP1 significantly reduced IRF1 expression. IL1B-induced expression of CXCL10 was largely insensitive to dexamethasone, whereas other DUSP1-enhanced, IRF1-dependent mRNAs showed various degrees of repression. With IL1B plus dexamethasone, CXCL10 expression was also IRF1-dependent, and expression was reduced by DUSP1 silencing. Thus, IL1B plus dexamethasone-induced DUSP1 maintains expression of IRF1 and the IRF1-dependent gene, CXCL10. This is supported by chromatin immunoprecipitation showing IRF1 recruitment to be essentially unaffected by dexamethasone at the CXCL10 promoter or at the promoters of more highly repressed IRF1-dependent genes. Since IRF1-dependent genes, such as CXCL10, are central to host defense, these data may help explain the reduced effectiveness of glucocorticoids during asthma exacerbations.
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Affiliation(s)
- Suharsh Shah
- From the Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada T2N 4Z6 and
| | - Elizabeth M King
- From the Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada T2N 4Z6 and
| | - Mahmoud M Mostafa
- From the Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada T2N 4Z6 and
| | - Mohammed O Altonsy
- From the Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada T2N 4Z6 and.,Department of Zoology, Sohag University, Sohag 825224, Egypt
| | - Robert Newton
- From the Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada T2N 4Z6 and
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16
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Shah S, Mostafa MM, McWhae A, Traves SL, Newton R. Negative Feed-forward Control of Tumor Necrosis Factor (TNF) by Tristetraprolin (ZFP36) Is Limited by the Mitogen-activated Protein Kinase Phosphatase, Dual-specificity Phosphatase 1 (DUSP1): IMPLICATIONS FOR REGULATION BY GLUCOCORTICOIDS. J Biol Chem 2015; 291:110-25. [PMID: 26546680 DOI: 10.1074/jbc.m115.697599] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2015] [Indexed: 12/20/2022] Open
Abstract
TNF is central to inflammation and may play a role in the pathogenesis of asthma. The 3'-untranslated region of the TNF transcript contains AU-rich elements (AREs) that are targeted by the RNA-binding protein, tristetraprolin (also known as zinc finger protein 36 (ZFP36)), which is itself up-regulated by inflammatory stimuli, to promote mRNA degradation. Using primary human bronchial epithelial and pulmonary epithelial A549 cells, we confirm that interleukin-1β (IL1B) induces expression of dual-specificity phosphatase 1 (DUSP1), ZFP36, and TNF. Whereas IL1B-induced DUSP1 is involved in feedback control of MAPK pathways, ZFP36 exerts negative (incoherent) feed-forward control of TNF mRNA and protein expression. DUSP1 silencing increased IL1B-induced ZFP36 expression at 2 h and profoundly repressed TNF mRNA at 6 h. This was partly due to increased TNF mRNA degradation, an effect that was reduced by ZFP36 silencing. This confirms a regulatory network, whereby DUSP1-dependent negative feedback control reduces feed-forward control by ZFP36. Conversely, whereas DUSP1 overexpression and inhibition of MAPKs prevented IL1B-induced expression of ZFP36, this was associated with increased TNF mRNA expression at 6 h, an effect that was predominantly due to elevated transcription. This points to MAPK-dependent feed-forward control of TNF involving ZFP36-dependent and -independent mechanisms. In terms of repression by dexamethasone, neither silencing of DUSP1, silencing of ZFP36, nor silencing of both together prevented the repression of IL1B-induced TNF expression, thereby demonstrating the need for further repressive mechanisms by anti-inflammatory glucocorticoids. In summary, these data illustrate why understanding the competing effects of feedback and feed-forward control is relevant to the development of novel anti-inflammatory therapies.
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Affiliation(s)
- Suharsh Shah
- From the Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta T2N 4Z6, Canada
| | - Mahmoud M Mostafa
- From the Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta T2N 4Z6, Canada
| | - Andrew McWhae
- From the Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta T2N 4Z6, Canada
| | - Suzanne L Traves
- From the Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta T2N 4Z6, Canada
| | - Robert Newton
- From the Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta T2N 4Z6, Canada
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17
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Gerber AN. Glucocorticoids and the Lung. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2015. [PMID: 26215999 DOI: 10.1007/978-1-4939-2895-8_12] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The lung is a major clinical target of glucocorticoid-based therapeutics, and GR signaling has broad effects on respiratory physiology and inflammation. During lung development, expression of GR in the mesenchyme is required for normal terminal alveolar epithelial differentiation. Prenatal administration of exogenous glucocorticoids (GCs) to prevent neonatal respiratory distress syndrome, however, promotes alveolar maturation and accelerates surfactant expression in a manner consistent with direct effects on the developing alveolar epithelium. Likewise, cell autonomous effects of GCs in regulating gene expression and phenotype of the airway epithelium and airway smooth muscle have been demonstrated to control important therapeutic effects of GCs in treating asthma and chronic obstructive pulmonary disease. Here, mechanisms and consequences of GR signaling in the developing lung and in treating obstructive lung disease are reviewed, with a focus on direct effects of GR signaling on alveolar differentiation, surfactant expression, and airway epithelial and smooth muscle pathophysiology.
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Affiliation(s)
- Anthony N Gerber
- Department of Medicine, National Jewish Health, University of Colorado, Denver, 1400 Jackson Street, Room K621b, Denver, CO, 80206, USA,
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18
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Lei K, Georgiou EX, Chen L, Yulia A, Sooranna SR, Brosens JJ, Bennett PR, Johnson MR. Progesterone and the Repression of Myometrial Inflammation: The Roles of MKP-1 and the AP-1 System. Mol Endocrinol 2015; 29:1454-67. [PMID: 26280733 DOI: 10.1210/me.2015-1122] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Progesterone (P4) maintains uterine quiescence during pregnancy and its functional withdrawal is associated with increased prostaglandin synthesis and the onset of labor. In primary human myometrial cells, the glucocorticoid receptor (GR) rather than the P4 receptor mediates P4 antagonism of IL-1β-induced cyclooxygenase-2 (COX-2) expression, the rate-limiting enzyme in prostaglandin synthesis. We now report that P4 also acts via GR to induce MAPK phosphatase (MKP)-1 and knockdown of MKP-1 impairs the ability of P4 to repress IL-1β-dependent COX-2 induction. Microarray analysis revealed that P4 repressed preferentially activator protein-1-responsive genes in response to IL-1β. Consistent with these observations, we found that the ability of P4 to reduce c-Jun activation was lost upon GR as well as MKP-1 knockdown. Interestingly, c-Jun levels in human myometrial cells declined upon GR and MKP-1 knockdown, which suggests the presence of an activator protein-1 feedback loop. This is supported by our observation that c-Jun levels declined after an initial rise in primary myometrial cells treated with phorbol 12-myrisatate 13-acetate, a potent activator of c-Jun N-terminal kinase. Finally, we show that MKP-1 is an intermediate in P4-mediated repression of some but not all IL-1β-responsive genes. For example, P4 repression of IL11 and IRAK3 was maintained upon MKP-1 knockdown. Taken together, the data show that P4 acts via GR to drive MKP-1 expression, which in turn inhibits IL-1β-dependent c-Jun activation and COX-2 expression.
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Affiliation(s)
- K Lei
- Imperial College Parturition Research Group (K.L., E.X.G., L.C., A.Y., S.R.S., M.R.J.), Chelsea and Westminster Hospital, London SW10 9NH, United Kingdom; Institute of Reproductive and Developmental Biology (KL.,. E.X.G., A.Y., S.R.S., P.R.B., M.R.J.), Hammersmith Hospital Campus, London W12 0NN, United Kingdom; Obstetrics Department (L.C.), First Affiliated Hospital of Nanjing Medical University, Nanjing Medical University, Nanjing 210029, People's Republic of China; and Reproductive Health (J.J.B.), University of Warwick, Coventry CV4 7AL, United Kingdom
| | - E X Georgiou
- Imperial College Parturition Research Group (K.L., E.X.G., L.C., A.Y., S.R.S., M.R.J.), Chelsea and Westminster Hospital, London SW10 9NH, United Kingdom; Institute of Reproductive and Developmental Biology (KL.,. E.X.G., A.Y., S.R.S., P.R.B., M.R.J.), Hammersmith Hospital Campus, London W12 0NN, United Kingdom; Obstetrics Department (L.C.), First Affiliated Hospital of Nanjing Medical University, Nanjing Medical University, Nanjing 210029, People's Republic of China; and Reproductive Health (J.J.B.), University of Warwick, Coventry CV4 7AL, United Kingdom
| | - L Chen
- Imperial College Parturition Research Group (K.L., E.X.G., L.C., A.Y., S.R.S., M.R.J.), Chelsea and Westminster Hospital, London SW10 9NH, United Kingdom; Institute of Reproductive and Developmental Biology (KL.,. E.X.G., A.Y., S.R.S., P.R.B., M.R.J.), Hammersmith Hospital Campus, London W12 0NN, United Kingdom; Obstetrics Department (L.C.), First Affiliated Hospital of Nanjing Medical University, Nanjing Medical University, Nanjing 210029, People's Republic of China; and Reproductive Health (J.J.B.), University of Warwick, Coventry CV4 7AL, United Kingdom
| | - A Yulia
- Imperial College Parturition Research Group (K.L., E.X.G., L.C., A.Y., S.R.S., M.R.J.), Chelsea and Westminster Hospital, London SW10 9NH, United Kingdom; Institute of Reproductive and Developmental Biology (KL.,. E.X.G., A.Y., S.R.S., P.R.B., M.R.J.), Hammersmith Hospital Campus, London W12 0NN, United Kingdom; Obstetrics Department (L.C.), First Affiliated Hospital of Nanjing Medical University, Nanjing Medical University, Nanjing 210029, People's Republic of China; and Reproductive Health (J.J.B.), University of Warwick, Coventry CV4 7AL, United Kingdom
| | - S R Sooranna
- Imperial College Parturition Research Group (K.L., E.X.G., L.C., A.Y., S.R.S., M.R.J.), Chelsea and Westminster Hospital, London SW10 9NH, United Kingdom; Institute of Reproductive and Developmental Biology (KL.,. E.X.G., A.Y., S.R.S., P.R.B., M.R.J.), Hammersmith Hospital Campus, London W12 0NN, United Kingdom; Obstetrics Department (L.C.), First Affiliated Hospital of Nanjing Medical University, Nanjing Medical University, Nanjing 210029, People's Republic of China; and Reproductive Health (J.J.B.), University of Warwick, Coventry CV4 7AL, United Kingdom
| | - J J Brosens
- Imperial College Parturition Research Group (K.L., E.X.G., L.C., A.Y., S.R.S., M.R.J.), Chelsea and Westminster Hospital, London SW10 9NH, United Kingdom; Institute of Reproductive and Developmental Biology (KL.,. E.X.G., A.Y., S.R.S., P.R.B., M.R.J.), Hammersmith Hospital Campus, London W12 0NN, United Kingdom; Obstetrics Department (L.C.), First Affiliated Hospital of Nanjing Medical University, Nanjing Medical University, Nanjing 210029, People's Republic of China; and Reproductive Health (J.J.B.), University of Warwick, Coventry CV4 7AL, United Kingdom
| | - P R Bennett
- Imperial College Parturition Research Group (K.L., E.X.G., L.C., A.Y., S.R.S., M.R.J.), Chelsea and Westminster Hospital, London SW10 9NH, United Kingdom; Institute of Reproductive and Developmental Biology (KL.,. E.X.G., A.Y., S.R.S., P.R.B., M.R.J.), Hammersmith Hospital Campus, London W12 0NN, United Kingdom; Obstetrics Department (L.C.), First Affiliated Hospital of Nanjing Medical University, Nanjing Medical University, Nanjing 210029, People's Republic of China; and Reproductive Health (J.J.B.), University of Warwick, Coventry CV4 7AL, United Kingdom
| | - M R Johnson
- Imperial College Parturition Research Group (K.L., E.X.G., L.C., A.Y., S.R.S., M.R.J.), Chelsea and Westminster Hospital, London SW10 9NH, United Kingdom; Institute of Reproductive and Developmental Biology (KL.,. E.X.G., A.Y., S.R.S., P.R.B., M.R.J.), Hammersmith Hospital Campus, London W12 0NN, United Kingdom; Obstetrics Department (L.C.), First Affiliated Hospital of Nanjing Medical University, Nanjing Medical University, Nanjing 210029, People's Republic of China; and Reproductive Health (J.J.B.), University of Warwick, Coventry CV4 7AL, United Kingdom
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19
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Gueta I, Shoenfeld Y, Orbach H. Intravenous immune globulins (IVIg) treatment for organizing pneumonia in a selective IgG immune deficiency state. Immunol Res 2015; 60:165-9. [PMID: 25391610 DOI: 10.1007/s12026-014-8571-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
We describe herein a 61-year-old woman who presented with fever, night sweats and cough. The diagnosis of pneumonia was established, but with symptom recurrence following antibiotic therapy, further diagnostics were performed. Biopsy via bronchoscopy revealed cryptogenic organizing pneumonia, and later on follow-up, a selective IgG immune deficiency was also diagnosed. Initial treatment of high-dose glucocorticoid therapy induced remission, but with dose reduction recurrence was observed. Intravenous immune globulin treatment was initiated and induced a successful clinical and radiological remission. Few cases of cryptogenic organizing pneumonia and hypogammaglobulinemia have been reported. To our knowledge, this is the fourth case described of cryptogenic organizing pneumonia with a hypogammaglobulinemia state and the first reported case of a selective immune deficiency state treated successfully with intravenous immune globulins.
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Affiliation(s)
- Itai Gueta
- Department of Medicine B, Wolfson Medical Center, Holon, Israel
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20
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Rudisch A, Dewhurst MR, Horga LG, Kramer N, Harrer N, Dong M, van der Kuip H, Wernitznig A, Bernthaler A, Dolznig H, Sommergruber W. High EMT Signature Score of Invasive Non-Small Cell Lung Cancer (NSCLC) Cells Correlates with NFκB Driven Colony-Stimulating Factor 2 (CSF2/GM-CSF) Secretion by Neighboring Stromal Fibroblasts. PLoS One 2015; 10:e0124283. [PMID: 25919140 PMCID: PMC4412534 DOI: 10.1371/journal.pone.0124283] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2014] [Accepted: 03/12/2015] [Indexed: 12/23/2022] Open
Abstract
We established co-cultures of invasive or non-invasive NSCLC cell lines and various types of fibroblasts (FBs) to more precisely characterize the molecular mechanism of tumor-stroma crosstalk in lung cancer. The HGF-MET-ERK1/2-CREB-axis was shown to contribute to the onset of the invasive phenotype of Calu-1 with HGF being secreted by FBs. Differential expression analysis of the respective mono- and co-cultures revealed an upregulation of NFκB-related genes exclusively in co-cultures with Calu-1. Cytokine Array- and ELISA-based characterization of the “cytokine fingerprints” identified CSF2 (GM-CSF), CXCL1, CXCL6, VEGF, IL6, RANTES and IL8 as being specifically upregulated in various co-cultures. Whilst CXCL6 exhibited a strictly FB-type-specific induction profile regardless of the invasiveness of the tumor cell line, CSF2 was only induced in co-cultures of invasive cell lines regardless of the partnered FB type. These cultures revealed a clear link between the induction of CSF2 and the EMT signature of the cancer cell line. The canonical NFκB signaling in FBs, but not in tumor cells, was shown to be responsible for the induced and constitutive CSF2 expression. In addition to CSF2, cytokine IL6, IL8 and IL1B, and chemokine CXCL1 and CXCL6 transcripts were also shown to be increased in co-cultured FBs. In contrast, their induction was not strictly dependent on the invasiveness of the co-cultured tumor cell. In a multi-reporter assay, additional signaling pathways (AP-1, HIF1-α, KLF4, SP-1 and ELK-1) were found to be induced in FBs co-cultured with Calu-1. Most importantly, no difference was observed in the level of inducibility of these six signaling pathways with regard to the type of FBs used. Finally, upon tumor fibroblast interaction the massive induction of chemokines such as CXCL1 and CXCL6 in FBs might be responsible for increased recruitment of a monocytic cell line (THP-1) in a transwell assay.
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MESH Headings
- Animals
- Cadherins/metabolism
- Carcinoma, Non-Small-Cell Lung/genetics
- Carcinoma, Non-Small-Cell Lung/metabolism
- Carcinoma, Non-Small-Cell Lung/pathology
- Cell Communication/drug effects
- Cell Line, Tumor
- Cytokines/metabolism
- Dermis/pathology
- Epithelial-Mesenchymal Transition/drug effects
- Epithelial-Mesenchymal Transition/genetics
- Fibroblasts/drug effects
- Fibroblasts/metabolism
- Gene Expression Profiling
- Gene Expression Regulation, Neoplastic/drug effects
- Gene Regulatory Networks/drug effects
- Genes, Reporter
- Granulocyte-Macrophage Colony-Stimulating Factor/metabolism
- Hepatocyte Growth Factor/pharmacology
- Humans
- Inflammation/pathology
- Kruppel-Like Factor 4
- Lung Neoplasms/genetics
- Lung Neoplasms/metabolism
- Lung Neoplasms/pathology
- NF-kappa B/metabolism
- Neoplasm Invasiveness
- Phenotype
- Proto-Oncogene Proteins c-met/metabolism
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Rats
- Signal Transduction/drug effects
- Signal Transduction/genetics
- Spheroids, Cellular/drug effects
- Spheroids, Cellular/metabolism
- Spheroids, Cellular/pathology
- Stromal Cells/metabolism
- Up-Regulation/drug effects
- Up-Regulation/genetics
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Affiliation(s)
- Albin Rudisch
- Department of Lead Discovery, Boehringer Ingelheim RCV GmbH & Co KG, Vienna, Austria
- Department of Microbiology, Immunobiology and Genetics, Center of Molecular Biology, Max F. Perutz Laboratories, University of Vienna, Vienna, Austria
| | | | | | - Nina Kramer
- Institute of Medical Genetics, Medical University of Vienna, Vienna, Austria
| | - Nathalie Harrer
- Department of Lead Discovery, Boehringer Ingelheim RCV GmbH & Co KG, Vienna, Austria
| | - Meng Dong
- Dr. Margarete Fischer-Bosch Institute of Clinical Pharmacology and University of Tübingen, Stuttgart, Baden-Württemberg, Germany
| | - Heiko van der Kuip
- Dr. Margarete Fischer-Bosch Institute of Clinical Pharmacology and University of Tübingen, Stuttgart, Baden-Württemberg, Germany
| | - Andreas Wernitznig
- Department of Lead Discovery, Boehringer Ingelheim RCV GmbH & Co KG, Vienna, Austria
| | - Andreas Bernthaler
- Department of Lead Discovery, Boehringer Ingelheim RCV GmbH & Co KG, Vienna, Austria
| | - Helmut Dolznig
- Institute of Medical Genetics, Medical University of Vienna, Vienna, Austria
| | - Wolfgang Sommergruber
- Department of Lead Discovery, Boehringer Ingelheim RCV GmbH & Co KG, Vienna, Austria
- * E-mail:
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21
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Sturrock A, Baker JA, Mir-Kasimov M, Paine R. Contrasting effects of hyperoxia on GM-CSF gene transcription in alveolar epithelial cells and T cells. Physiol Rep 2015; 3:3/3/e12324. [PMID: 25747588 PMCID: PMC4393158 DOI: 10.14814/phy2.12324] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Granulocyte/macrophage colony-stimulating factor (GM-CSF) is critically important for normal pulmonary innate immunity and for functional maturation of alveolar macrophages. Alveolar epithelial cells (AEC) are a major source of GM-CSF in the lung and express this growth factor constitutively, whereas most other cells, including T cells, express GM-CSF following inflammatory stimulation. AEC expression of GM-CSF is suppressed by oxidative stress, at least in part through induction of microRNA leading to increased mRNA turnover. In this report, we compare and contrast the effect of hyperoxia on transcriptional aspects of gene regulation of GM-CSF in lung epithelia and T cells of human and mouse origin. Similar to primary murine AEC, human H820 cells that express multiple characteristics of normal alveolar epithelial cells express GM-CSF constitutively, with decreased expression and increased mRNA turnover following exposure to hyperoxia. In contrast, hyperoxia induces augmented GM-CSF expression in human and murine activated T cells, in association with enhanced GM-CSF mRNA stability. Alveolar epithelial cells demonstrate constitutive transcription, with the proximal promoter in an open configuration in normoxia, without change in hyperoxia. Conversely, in both human and murine T cells, hyperoxia increased GM-CSF gene transcription. The proximal promoter was in a closed configuration in unstimulated T cells but became accessible upon activation and still more accessible in activated T cells exposed to hyperoxia. These fundamental differences in molecular regulation of GM-CSF expression highlight the distinctive niche of alveolar epithelial cell expression of GM-CSF and offer insights into the biology of GM-CSF in the setting of acute lung injury.
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Affiliation(s)
- Anne Sturrock
- Department of Veterans, Affairs Medical Center, Salt Lake City, Utah, USA Division of Respiratory, Critical Care and Occupational Pulmonary Medicine, University of Utah School of Medicine, Salt Lake City, Utah, USA
| | - Jessica A Baker
- Department of Veterans, Affairs Medical Center, Salt Lake City, Utah, USA Division of Respiratory, Critical Care and Occupational Pulmonary Medicine, University of Utah School of Medicine, Salt Lake City, Utah, USA
| | - Mustafa Mir-Kasimov
- Department of Veterans, Affairs Medical Center, Salt Lake City, Utah, USA Division of Respiratory, Critical Care and Occupational Pulmonary Medicine, University of Utah School of Medicine, Salt Lake City, Utah, USA
| | - Robert Paine
- Department of Veterans, Affairs Medical Center, Salt Lake City, Utah, USA Division of Respiratory, Critical Care and Occupational Pulmonary Medicine, University of Utah School of Medicine, Salt Lake City, Utah, USA
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22
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Keenan CR, Radojicic D, Li M, Radwan A, Stewart AG. Heterogeneity in mechanisms influencing glucocorticoid sensitivity: the need for a systems biology approach to treatment of glucocorticoid-resistant inflammation. Pharmacol Ther 2015; 150:81-93. [PMID: 25596317 DOI: 10.1016/j.pharmthera.2015.01.006] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2015] [Accepted: 01/05/2015] [Indexed: 12/14/2022]
Abstract
Glucocorticoids (GCs) have impressive anti-inflammatory and immunosuppressive effects and show a diversity of actions across a variety of cell phenotypes. Implicit in efforts to optimize GCs as anti-inflammatory agents for any or all indications is the notion that the relevant mechanism(s) of action of GCs are fully elucidated. However, recent advances in understanding GC signalling mechanisms have revealed remarkable complexity and contextual dependence, calling into question whether the mechanisms of action are sufficiently well-described to embark on optimization. In the current review, we address evidence for differences in the mechanism of action in different cell types and contexts, and discuss contrasts in mechanisms of glucocorticoid insensitivity, with a focus on asthma and Chronic Obstructive Pulmonary Disease (COPD). Given this complexity, we consider the potential breadth of impact and selectivity of strategies directed to reversing the glucocorticoid insensitivity.
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Affiliation(s)
- Christine R Keenan
- Lung Health Research Centre, Department of Pharmacology and Therapeutics, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Danica Radojicic
- Lung Health Research Centre, Department of Pharmacology and Therapeutics, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Meina Li
- Lung Health Research Centre, Department of Pharmacology and Therapeutics, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Asmaa Radwan
- Lung Health Research Centre, Department of Pharmacology and Therapeutics, The University of Melbourne, Parkville, Victoria 3010, Australia
| | - Alastair G Stewart
- Lung Health Research Centre, Department of Pharmacology and Therapeutics, The University of Melbourne, Parkville, Victoria 3010, Australia.
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23
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Bao A, Li F, Zhang M, Chen Y, Zhang P, Zhou X. Impact of ozone exposure on the response to glucocorticoid in a mouse model of asthma: involvements of p38 MAPK and MKP-1. Respir Res 2014; 15:126. [PMID: 25287866 PMCID: PMC4196074 DOI: 10.1186/s12931-014-0126-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2014] [Accepted: 10/02/2014] [Indexed: 11/12/2022] Open
Abstract
Background Molecular mechanisms involved in the oxidative stress induced glucocorticoids insensitivity remain elusive. The mitogen-activated protein kinase phosphatase (MKP) 1 mediates a part of glucocorticoids action and can be modified by exogenous oxidants. Whether oxidant ozone (O3) can affect the function of MKP-1 and hence blunt the response to corticotherapy is not clear. Methods Here we employed a murine model of asthma established with ovalbumin (OVA) sensitization and challenge to evaluate the influence of O3 on the inhibitory effect of dexamethasone on AHR and airway inflammation, and by administration of SB239063, a selective p38 MAPK inhibitor, to explore the underlying involvements of the activation of p38 MAPK and the expression of MKP-1. Results Ozone exposure not only aggravated the pulmonary inflammation and AHR, but also decreased the inhibitory effects of dexamethasone, accompanied by the elevated oxidative stress, airway neutrophilia, enhanced phosphorylation of p38 MAPK, and upregulated expression of IL-17. Administration of SB239063 caused significant inhibition of the p38 MAPK phosphorylation, alleviation of the airway neutrophilia, and decrement of the ozone-induced IL-17 expression, and partly restored the ozone-impaired effects of dexamethasone. Ozone exposure not only decreased the protein expression of MKP-1, but also diminished the dexamethasone-mediated induction process of MKP-1 mRNA and protein expression. Conclusions The glucocorticoids insensitivity elicited by ozone exposure on current asthma model may involve the enhanced phosphorylation of p38 MAPK and disturbed expression of MKP-1. Electronic supplementary material The online version of this article (doi:10.1186/s12931-014-0126-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
| | | | | | | | | | - Xin Zhou
- Department of Respiratory Medicine, Shanghai First People's Hospital, Shanghai Jiao tong University, 100 Haining Road, Shanghai 200080China.
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24
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Shah S, King EM, Chandrasekhar A, Newton R. Roles for the mitogen-activated protein kinase (MAPK) phosphatase, DUSP1, in feedback control of inflammatory gene expression and repression by dexamethasone. J Biol Chem 2014; 289:13667-79. [PMID: 24692548 DOI: 10.1074/jbc.m113.540799] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Glucocorticoids act on the glucocorticoid receptor (NR3C1) to repress inflammatory gene expression. This is central to their anti-inflammatory effectiveness and rational improvements in therapeutic index depend on understanding the mechanism. Human pulmonary epithelial A549 cells were used to study the role of the mitogen-activated protein kinase (MAPK) phosphatase, dual-specificity phosphatase 1 (DUSP1), in the dexamethasone repression of 11 inflammatory genes induced, in a MAPK-dependent manner, by interleukin-1β (IL1B). Adenoviral over-expression of DUSP1 inactivated MAPK pathways and reduced expression of all 11 inflammatory genes. IL1B rapidly induced DUSP1 expression and RNA silencing revealed a transient role in feedback inhibition of MAPKs and inflammatory gene expression. With dexamethasone, which induced DUSP1 expression, plus IL1B (co-treatment), DUSP1 expression was further enhanced. At 1 h, this was responsible for the dexamethasone inhibition of IL1B-induced MAPK activation and CXCL1 and CXCL2 mRNA expression, with a similar trend for CSF2. Whereas, CCL20 mRNA was not repressed by dexamethasone at 1 h, repression of CCL2, CXCL3, IL6, and IL8 was unaffected, and PTGS2 repression was partially affected by DUSP1 knockdown. At later times, dexamethasone repression of MAPKs was unaffected by DUSP1 silencing. Likewise, 6 h post-IL1B, dexamethasone repression of all 11 mRNAs was essentially unaffected by DUSP1 knockdown. Qualitatively similar data were obtained for CSF2, CXCL1, IL6, and IL8 release. Thus, despite general roles in feedback inhibition, DUSP1 plays a transient, often partial, role in the dexamethasone-dependent repression of certain inflammatory genes. Therefore this also illustrates key roles for DUSP1-independent effectors in mediating glucocorticoid-dependent repression.
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Affiliation(s)
- Suharsh Shah
- From the Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta T2N 4Z6, Canada
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25
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Wang X, Shannahan JH, Brown JM. IL-33 modulates chronic airway resistance changes induced by multi-walled carbon nanotubes. Inhal Toxicol 2014; 26:240-9. [PMID: 24502429 DOI: 10.3109/08958378.2014.880202] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
OBJECTIVE Instillation of multi-walled carbon nanotubes (MWCNTs) in C57BL/6 mice results in decrements of pulmonary function specifically characterized by increases in airway resistance. In this study, we examined possible mechanisms responsible for these alterations following MWCNT exposure, including the roles of IL-33 and chronic inflammation. MATERIALS AND METHODS To elucidate the role of IL-33, we assessed lung histology and pulmonary function in C57BL/6 and IL-33(-/-) mice 30 days following MWCNT instillation. In addition, the impact of MWCNT instillation on airway hyperresponsiveness (AHR) was assessed by methacholine challenges of C57BL/6 and IL-33(-/-) mice. To further understand the mechanisms by which MWCNTs may increase airway constriction, C57BL/6 mice were treated with aerosolized albuterol or injected with multiple doses of methylprednisolone via intra-peritoneal injections prior to the assessment of MWCNT-induced changes in pulmonary function. RESULTS Total cell count, macrophages, and neutrophils were increased in the lavage fluid of C57BL/6 mice, but not in IL-33(-/-) mice, following MWCNT exposure. C57BL/6 mice displayed increased inflammation and fibrosis located proximal to the airways which was absent in IL-33(-/-) mice. Aerosolized methacholine increased parameters of airway resistance (R and Rn) in a dose-dependent manner in all groups, with MWCNT-instilled C57BL/6 mice responding more robustly compared to the controls, while no differences were found in IL-33(-/-) mice due to MWCNT exposure. Treatment with methylprednisolone reduced both the MWCNT-induced histopathological changes and increases in R and Rn in C57BL/6 mice. CONCLUSION These findings suggest that IL-33 and chronic inflammation in general are critical in the pulmonary toxicity induced by MWCNT resulting in modified pulmonary function.
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Affiliation(s)
- Xiaojia Wang
- Department of Physiology, Brody School of Medicine, East Carolina University , Greenville, NC , USA and
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26
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Wang Y, Han G, Wang K, Liu G, Wang R, Xiao H, Li X, Hou C, Shen B, Guo R, Li Y, Chen G. Tumor-Derived GM-CSF Promotes Inflammatory Colon Carcinogenesis via Stimulating Epithelial Release of VEGF. Cancer Res 2013; 74:716-26. [DOI: 10.1158/0008-5472.can-13-1459] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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27
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Holden NS, George T, Rider CF, Chandrasekhar A, Shah S, Kaur M, Johnson M, Siderovski DP, Leigh R, Giembycz MA, Newton R. Induction of regulator of G-protein signaling 2 expression by long-acting β2-adrenoceptor agonists and glucocorticoids in human airway epithelial cells. J Pharmacol Exp Ther 2013; 348:12-24. [PMID: 24163441 DOI: 10.1124/jpet.113.204586] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
In asthma and chronic obstructive pulmonary disease (COPD) multiple mediators act on Gαq-linked G-protein-coupled receptors (GPCRs) to cause bronchoconstriction. However, acting on the airway epithelium, such mediators may also elicit inflammatory responses. In human bronchial epithelial BEAS-2B cells (bronchial epithelium + adenovirus 12-SV40 hybrid), regulator of G-protein signaling (RGS) 2 mRNA and protein were synergistically induced in response to combinations of long-acting β2-adrenoceptor agonist (LABA) (salmeterol, formoterol) plus glucocorticoid (dexamethasone, fluticasone propionate, budesonide). Equivalent responses occurred in primary human bronchial epithelial cells. Concentrations of glucocorticoid plus LABA required to induce RGS2 expression in BEAS-2B cells were consistent with the levels achieved therapeutically in the lungs. As RGS2 is a GTPase-activating protein that switches off Gαq, intracellular free calcium ([Ca(2+)]i) flux was used as a surrogate of responses induced by histamine, methacholine, and the thromboxane receptor agonist U46619 [(Z)-7-[(1S,4R,5R,6S)-5-[(E,3S)-3-hydroxyoct-1-enyl]-3-oxabicyclo[2.2.1]heptan-6-yl]hept-5-enoic acid]. This was significantly attenuated by salmeterol plus dexamethasone pretreatment, or RGS2 overexpression, and the protective effect of salmeterol plus dexamethasone was abolished by RGS2 RNA silencing. Although methacholine and U46619 induced interleukin-8 (IL-8) release and this was inhibited by RGS2 overexpression, the repression of U46619-induced IL-8 release by salmeterol plus dexamethasone was unaffected by RGS2 knockdown. Given a role for Gαq-mediated pathways in inducing IL-8 release, we propose that RGS2 acts redundantly with other effector processes to repress IL-8 expression. Thus, RGS2 expression is a novel effector mechanism in the airway epithelium that is induced by glucocorticoid/LABA combinations. This could contribute to the efficacy of glucocorticoid/LABA combinations in asthma and COPD.
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Affiliation(s)
- Neil S Holden
- Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, Faculty of Medicine, University of Calgary, Calgary, Alberta, Canada (N.S.H., T.G., C.F.R., A.C., S.S., M.K., R.L., M.A.G., R.N.); GlaxoSmithKline Research and Development, Uxbridge, Middlesex, United Kingdom (M.J.); and Department of Physiology and Pharmacology, School of Medicine, West Virginia University, Morgantown, West Virginia (D.P.S.)
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28
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Spliethoff K, Meier D, Aeberli I, Gassmann M, Langhans W, Maggiorini M, Lutz TA, Goetze O. Reduced Insulin Sensitivity as a Marker for Acute Mountain Sickness? High Alt Med Biol 2013; 14:240-50. [DOI: 10.1089/ham.2012.1128] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Affiliation(s)
- Kerstin Spliethoff
- Institute of Veterinary Physiology, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
- Zurich Centre for Integrative Human Physiology (ZIHP) Zurich, Switzerland
| | - Daniela Meier
- Institute of Veterinary Physiology, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
| | - Isabelle Aeberli
- Clinic for Endocrinology, Diabetes and Clinical Nutrition, University Hospital Zurich, Zurich, Switzerland
| | - Max Gassmann
- Institute of Veterinary Physiology, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
- Zurich Centre for Integrative Human Physiology (ZIHP) Zurich, Switzerland
- Universidad Peruana Cayetano Heredia (UPCH), Lima, Peru
| | - Wolfgang Langhans
- Physiology and Behavior Laboratory, Institute of Food, Nutrition and Health, ETH Zurich, Zurich, Switzerland
- Zurich Centre for Integrative Human Physiology (ZIHP) Zurich, Switzerland
| | - Marco Maggiorini
- Medical Intensive Care Unit, University Hospital Zurich, Zurich, Switzerland
- Zurich Centre for Integrative Human Physiology (ZIHP) Zurich, Switzerland
| | - Thomas A. Lutz
- Institute of Veterinary Physiology, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland
- Zurich Centre for Integrative Human Physiology (ZIHP) Zurich, Switzerland
| | - Oliver Goetze
- Division of Gastroenterology and Hepatology, University Hospital Zurich, Zurich, Switzerland
- Zurich Centre for Integrative Human Physiology (ZIHP) Zurich, Switzerland
- Division of Hepatology, Department of Medicine II, University Hospital Wuerzburg, Wuerzburg, Germany
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29
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Newton R. Anti-inflammatory glucocorticoids: changing concepts. Eur J Pharmacol 2013; 724:231-6. [PMID: 23747654 DOI: 10.1016/j.ejphar.2013.05.035] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2013] [Revised: 05/13/2013] [Accepted: 05/29/2013] [Indexed: 10/26/2022]
Abstract
Despite being the most effective anti-inflammatory treatment for chronic inflammatory diseases, the mechanisms by which glucocorticoids (corticosteroids) effect repression of inflammatory gene expression remain incompletely understood. Direct interaction of the glucocorticoid receptor (NR3C1) with inflammatory transcription factors to repress transcriptional activity, i.e. transrepression, represents one mechanism of action. However, transcriptional activation, or transactivation, by NR3C1 also represents an important mechanism of glucocorticoid action. Glucocorticoids rapidly and profoundly increase expression of multiple genes, many with properties consistent with the repression of inflammatory gene expression. For example: the dual specificity phosphatase, DUSP1, reduces activation of mitogen-activated protein kinases; glucocorticoid-induced leucine zipper (TSC22D3) represses nuclear factor-κB (NF-κB) and activator protein 1 (AP-1) transcriptional responses; inhibitor of κBα (NFKBIA) inhibits NF-κB; tristraprolin (ZFP36) destabilises and translationally represses inflammatory mRNAs; CDKN1C, a cell cycle regulator, may attenuate JUN N-terminal kinase signalling; and regulator of G-protein signalling 2 (RGS2), by reducing signalling from Gαq-linked G protein-coupled receptors (GPCRs), is bronchoprotective. While glucocorticoid-dependent transrepression can co-exist with transactivation, transactivation may account for the greatest level and most potent repression of inflammatory genes. Equally, NR3C1 transactivation is enhanced by β2-adrenoceptor agonists and may explain the enhanced clinical efficacy of β2-adrenoceptor/glucocorticoid combination therapies in asthma and chronic obstructive pulmonary disease. Finally, NR3C1 transactivation is reduced by inflammatory stimuli, including respiratory syncytial virus and human rhinovirus. This provides an explanation for glucocorticoid resistance. Continuing efforts to understand roles for glucocorticoid-dependent transactivation will provide opportunities to improve glucocorticoid therapies.
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Affiliation(s)
- Robert Newton
- Department of Cell Biology and Anatomy, Airways Inflammation Research Group, Snyder Institute for Chronic Diseases, Faculty of Medicine, University of Calgary, 3330 Hospital Drive NW, Calgary, Alberta, Canada T2N 4N1.
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Long-acting β2-agonists increase fluticasone propionate-induced mitogen-activated protein kinase phosphatase 1 (MKP-1) in airway smooth muscle cells. PLoS One 2013; 8:e59635. [PMID: 23533638 PMCID: PMC3606114 DOI: 10.1371/journal.pone.0059635] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2012] [Accepted: 02/16/2013] [Indexed: 11/19/2022] Open
Abstract
Mitogen-activated protein kinase phosphatase 1 (MKP-1) represses MAPK-driven signalling and plays an important anti-inflammatory role in asthma and airway remodelling. Although MKP-1 is corticosteroid-responsive and increased by cAMP-mediated signalling, the upregulation of this critical anti-inflammatory protein by long-acting β2-agonists and clinically-used corticosteroids has been incompletely examined to date. To address this, we investigated MKP-1 gene expression and protein upregulation induced by two long-acting β2-agonists (salmeterol and formoterol), alone or in combination with the corticosteroid fluticasone propionate (abbreviated as fluticasone) in primary human airway smooth muscle (ASM) cells in vitro. β2-agonists increased MKP-1 protein in a rapid but transient manner, while fluticasone induced sustained upregulation. Together, long-acting β2-agonists increased fluticasone-induced MKP-1 and modulated ASM synthetic function (measured by interleukin 6 (IL-6) and interleukin 8 (IL-8) secretion). As IL-6 expression (like MKP-1) is cAMP/adenylate cyclase-mediated, the long-acting β2-agonist formoterol increased IL-6 mRNA expression and secretion. Nevertheless, when added in combination with fluticasone, β2-agonists significantly repressed IL-6 secretion induced by tumour necrosis factor α (TNFα). Conversely, as IL-8 is not cAMP-responsive, β2-agonists significantly inhibited TNFα-induced IL-8 in combination with fluticasone, where fluticasone alone was without repressive effect. In summary, long-acting β2-agonists increase fluticasone-induced MKP-1 in ASM cells and repress synthetic function of this immunomodulatory airway cell type.
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Ammit AJ. Glucocorticoid insensitivity as a source of drug targets for respiratory disease. Curr Opin Pharmacol 2013; 13:370-6. [PMID: 23434363 DOI: 10.1016/j.coph.2013.02.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2012] [Revised: 01/24/2013] [Accepted: 02/04/2013] [Indexed: 11/25/2022]
Abstract
Glucocorticoids (corticosteroids) are effective and clinically useful medicines for repressing inflammation in lung disease; however, the number of respiratory conditions that have been recognized to be refractory or insensitive to glucocorticoids is on the rise--either due to an inherent difference in the glucocorticoid sensitivity as part of the disease process or due to exogenous stressors such as cigarette smoke and other oxidative insults. Independent of causality, the aim of future therapeutic advances to conquer this frontier will no doubt be based on our growing knowledge of molecular mechanisms underlying glucocorticoid insensitivity in respiratory diseases. The current article aims to highlight the key molecular mechanisms responsible for glucocorticoid insensitivity in asthma and COPD. This new knowledge will ultimately allow us to enhance lung health by restoring glucocorticoid responsiveness in respiratory disease. In this way, our increased understanding of corticosteroid insensitivity can be exploited as a source of drug targets for respiratory disease in the future.
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Affiliation(s)
- Alaina J Ammit
- Faculty of Pharmacy, University of Sydney, NSW 2006, Australia.
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Glucocorticoid repression of inflammatory gene expression shows differential responsiveness by transactivation- and transrepression-dependent mechanisms. PLoS One 2013; 8:e53936. [PMID: 23349769 PMCID: PMC3545719 DOI: 10.1371/journal.pone.0053936] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2012] [Accepted: 12/04/2012] [Indexed: 12/25/2022] Open
Abstract
Binding of glucocorticoid to the glucocorticoid receptor (GR/NR3C1) may repress inflammatory gene transcription via direct, protein synthesis-independent processes (transrepression), or by activating transcription (transactivation) of multiple anti-inflammatory/repressive factors. Using human pulmonary A549 cells, we showed that 34 out of 39 IL-1β-inducible mRNAs were repressed to varying degrees by the synthetic glucocorticoid, dexamethasone. Whilst these repressive effects were GR-dependent, they did not correlate with either the magnitude of IL-1β-inducibility or the NF-κB-dependence of the inflammatory genes. This suggests that induction by IL-1β and repression by dexamethasone are independent events. Roles for transactivation were investigated using the protein synthesis inhibitor, cycloheximide. However, cycloheximide reduced the IL-1β-dependent expression of 13 mRNAs, which, along with the 5 not showing repression by dexamethasone, were not analysed further. Of the remaining 21 inflammatory mRNAs, cycloheximide significantly attenuated the dexamethasone-dependent repression of 11 mRNAs that also showed a marked time-dependence to their repression. Such effects are consistent with repression occurring via the de novo synthesis of a new product, or products, which subsequently cause repression (i.e., repression via a transactivation mechanism). Conversely, 10 mRNAs showed completely cycloheximide-independent, and time-independent, repression by dexamethasone. This is consistent with direct GR transrepression. Importantly, the inflammatory mRNAs showing attenuated repression by dexamethasone in the presence of cycloheximide also showed a significantly greater extent of repression and a higher potency to dexamethasone compared to those mRNAs showing cycloheximide-independent repression. This suggests that the repression of inflammatory mRNAs by GR transactivation-dependent mechanisms accounts for the greatest levels of repression and the most potent repression by dexamethasone. In conclusion, our data indicate roles for both transrepression and transactivation in the glucocorticoid-dependent repression of inflammatory gene expression. However, transactivation appears to account for the more potent and efficacious mechanism of repression by glucocorticoids on these IL-1β-induced genes.
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Kelly MM, King EM, Rider CF, Gwozd C, Holden NS, Eddleston J, Zuraw B, Leigh R, O'Byrne PM, Newton R. Corticosteroid-induced gene expression in allergen-challenged asthmatic subjects taking inhaled budesonide. Br J Pharmacol 2012; 165:1737-1747. [PMID: 21827450 DOI: 10.1111/j.1476-5381.2011.01620.x] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND AND PURPOSE Inhaled corticosteroids (ICS) are the cornerstone of asthma pharmacotherapy and, acting via the glucocorticoid receptor (GR), reduce inflammatory gene expression. While this is often attributed to a direct inhibitory effect of the GR on inflammatory gene transcription, corticosteroids also induce the expression of anti-inflammatory genes in vitro. As there are no data to support this effect in asthmatic subjects taking ICS, we have assessed whether ICS induce anti-inflammatory gene expression in subjects with atopic asthma. EXPERIMENTAL APPROACH Bronchial biopsies from allergen-challenged atopic asthmatic subjects taking inhaled budesonide or placebo were subjected to gene expression analysis using real-time reverse transcriptase-PCR for the corticosteroid-inducible genes (official gene symbols with aliases in parentheses): TSC22D3 [glucocorticoid-induced leucine zipper (GILZ)], dual-specificity phosphatase-1 (MAPK phosphatase-1), both anti-inflammatory effectors, and FKBP5 [FK506-binding protein 51 (FKBP51)], a regulator of GR function. Cultured pulmonary epithelial and smooth muscle cells were also treated with corticosteroids before gene expression analysis. KEY RESULTS Compared with placebo, GILZ and FKBP51 mRNA expression was significantly elevated in budesonide-treated subjects. Budesonide also increased GILZ expression in human epithelial and smooth muscle cells in culture. Immunostaining of bronchial biopsies revealed GILZ expression in the airways epithelium and smooth muscle of asthmatic subjects. CONCLUSIONS AND IMPLICATIONS Expression of the corticosteroid-induced genes, GILZ and FKBP51, is up-regulated in the airways of allergen-challenged asthmatic subjects taking inhaled budesonide. Consequently, the biological effects of corticosteroid-induced genes should be considered when assessing the actions of ICS. Treatment modalities that increase or decrease GR-dependent transcription may correspondingly affect corticosteroid efficacy.
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Affiliation(s)
- M M Kelly
- Airways Inflammation Research Group, Institute of Infection, Immunity and Inflammation, Faculty of Medicine, University of Calgary, Calgary, AB, CanadaAllergy and Immunology Section, University of California, San Diego School of Medicine, La Jolla, CA, USAFirestone Institute for Respiratory Health, St. Joseph's Hospital and the Department of Medicine, McMaster University, Hamilton, ON, Canada
| | - E M King
- Airways Inflammation Research Group, Institute of Infection, Immunity and Inflammation, Faculty of Medicine, University of Calgary, Calgary, AB, CanadaAllergy and Immunology Section, University of California, San Diego School of Medicine, La Jolla, CA, USAFirestone Institute for Respiratory Health, St. Joseph's Hospital and the Department of Medicine, McMaster University, Hamilton, ON, Canada
| | - C F Rider
- Airways Inflammation Research Group, Institute of Infection, Immunity and Inflammation, Faculty of Medicine, University of Calgary, Calgary, AB, CanadaAllergy and Immunology Section, University of California, San Diego School of Medicine, La Jolla, CA, USAFirestone Institute for Respiratory Health, St. Joseph's Hospital and the Department of Medicine, McMaster University, Hamilton, ON, Canada
| | - C Gwozd
- Airways Inflammation Research Group, Institute of Infection, Immunity and Inflammation, Faculty of Medicine, University of Calgary, Calgary, AB, CanadaAllergy and Immunology Section, University of California, San Diego School of Medicine, La Jolla, CA, USAFirestone Institute for Respiratory Health, St. Joseph's Hospital and the Department of Medicine, McMaster University, Hamilton, ON, Canada
| | - N S Holden
- Airways Inflammation Research Group, Institute of Infection, Immunity and Inflammation, Faculty of Medicine, University of Calgary, Calgary, AB, CanadaAllergy and Immunology Section, University of California, San Diego School of Medicine, La Jolla, CA, USAFirestone Institute for Respiratory Health, St. Joseph's Hospital and the Department of Medicine, McMaster University, Hamilton, ON, Canada
| | - J Eddleston
- Airways Inflammation Research Group, Institute of Infection, Immunity and Inflammation, Faculty of Medicine, University of Calgary, Calgary, AB, CanadaAllergy and Immunology Section, University of California, San Diego School of Medicine, La Jolla, CA, USAFirestone Institute for Respiratory Health, St. Joseph's Hospital and the Department of Medicine, McMaster University, Hamilton, ON, Canada
| | - B Zuraw
- Airways Inflammation Research Group, Institute of Infection, Immunity and Inflammation, Faculty of Medicine, University of Calgary, Calgary, AB, CanadaAllergy and Immunology Section, University of California, San Diego School of Medicine, La Jolla, CA, USAFirestone Institute for Respiratory Health, St. Joseph's Hospital and the Department of Medicine, McMaster University, Hamilton, ON, Canada
| | - R Leigh
- Airways Inflammation Research Group, Institute of Infection, Immunity and Inflammation, Faculty of Medicine, University of Calgary, Calgary, AB, CanadaAllergy and Immunology Section, University of California, San Diego School of Medicine, La Jolla, CA, USAFirestone Institute for Respiratory Health, St. Joseph's Hospital and the Department of Medicine, McMaster University, Hamilton, ON, Canada
| | - P M O'Byrne
- Airways Inflammation Research Group, Institute of Infection, Immunity and Inflammation, Faculty of Medicine, University of Calgary, Calgary, AB, CanadaAllergy and Immunology Section, University of California, San Diego School of Medicine, La Jolla, CA, USAFirestone Institute for Respiratory Health, St. Joseph's Hospital and the Department of Medicine, McMaster University, Hamilton, ON, Canada
| | - R Newton
- Airways Inflammation Research Group, Institute of Infection, Immunity and Inflammation, Faculty of Medicine, University of Calgary, Calgary, AB, CanadaAllergy and Immunology Section, University of California, San Diego School of Medicine, La Jolla, CA, USAFirestone Institute for Respiratory Health, St. Joseph's Hospital and the Department of Medicine, McMaster University, Hamilton, ON, Canada
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Niisato N, Ohta M, Eaton DC, Marunaka Y. Hypotonic stress upregulates β- and γ-ENaC expression through suppression of ERK by inducing MKP-1. Am J Physiol Renal Physiol 2012; 303:F240-52. [PMID: 22573375 DOI: 10.1152/ajprenal.00198.2011] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
We investigated a physiological role for ERK, a member of the MAPK family, in the hypotonic stimulation of epithelial Na(+) channel (ENaC)-mediated Na(+) reabsorption in renal epithelial A6 cells. We show that hypotonic stress causes a major dephosphorylation of ERK following a rapid transient phosphorylation. PD98059 (a MEK inhibitor) increases dephosphorylated ERK and enhances the hypotonic-stress-stimulated Na(+) reabsorption. ERK dephosphorylation is mediated by MAPK phosphatase (MKP). Hypotonic stress activates p38, which in turn induces MKP-1 and to a lesser extent MKP-3 mRNA expression. Inhibition of p38 suppresses MKP-1 induction, preventing hypotonic stress from dephosphorylating ERK. Inhibition of MKP-1 and -3 by the inhibitor NSC95397 also suppresses the hypotonicity-induced dephosphorylation of ERK. NSC95397 reduces both β- and γ-ENaC mRNA expression and ENaC-mediated Na(+) reabsorption stimulated by hypotonic stress. In contrast, pretreatment with PD98059 significantly enhances mRNA and protein expression of β- and γ-ENaC even under isotonic conditions. However, PD98059 only stimulates Na(+) reabsorption in response to hypotonic stress, suggesting that ERK inactivation by itself (i.e., under isotonic conditions) is not sufficient to stimulate Na(+) reabsorption, even though ERK inactivation enhances β- and γ-ENaC expression. Based on these results, we conclude that hypotonic stress stimulates Na(+) reabsorption through at least two signaling pathways: 1) induction of MKP-1 that suppresses ERK activity and induces β- and γ-ENaC expression, and 2) promotion of translocation of the newly synthesized ENaC to the apical membrane.
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Affiliation(s)
- Naomi Niisato
- Department of Molecular Cell Physiology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, Japan
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Clark AR, Belvisi MG. Maps and legends: the quest for dissociated ligands of the glucocorticoid receptor. Pharmacol Ther 2011; 134:54-67. [PMID: 22212616 DOI: 10.1016/j.pharmthera.2011.12.004] [Citation(s) in RCA: 171] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2011] [Accepted: 12/07/2011] [Indexed: 01/19/2023]
Abstract
Glucocorticoids are steroid hormones that have pleiotropic effects on development, metabolism, cognitive function and other aspects of physiology. Since the demonstration more than sixty years ago of their capacity to suppress inflammation, synthetic glucocorticoids have been extremely widely used in the treatment of inflammatory diseases. However, their clinical use is limited by numerous, unpredictable and potentially serious side effects. Glucocorticoids regulate gene expression both positively and negatively. Both of these effects are mediated by the glucocorticoid receptor, a ligand-dependent transcription factor. It has become widely accepted that anti-inflammatory effects of glucocorticoids are mostly due to inhibition of transcription, whereas the activation of transcription by the glucocorticoid receptor accounts for the majority of side effects. This dogma (which we refer to as the "transrepression hypothesis") predicts the possibility of uncoupling therapeutic, anti-inflammatory effects from side effects by identifying novel, selective ligands of the glucocorticoid receptor, which preferentially mediate inhibition rather than activation of transcription. It is argued that such "dissociated" glucocorticoid receptor ligands should retain anti-inflammatory potency but cause fewer side effects. Here we critically re-examine the history and foundations of the transrepression hypothesis. We argue that it is incompatible with the complexity of gene regulation by glucocorticoids and poorly supported by experimental evidence; that it no longer aids clear thinking about the actions of the glucocorticoid receptor; and that it will not prove a fruitful basis for continued refinement and improvement of anti-inflammatory drugs that target the glucocorticoid receptor.
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Affiliation(s)
- Andrew R Clark
- Kennedy Institute of Rheumatology, Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, 65 Aspenlea Road, Hammersmith, London W6 8LH, United Kingdom.
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Rider CF, King EM, Holden NS, Giembycz MA, Newton R. Inflammatory stimuli inhibit glucocorticoid-dependent transactivation in human pulmonary epithelial cells: rescue by long-acting beta2-adrenoceptor agonists. J Pharmacol Exp Ther 2011; 338:860-9. [PMID: 21622733 DOI: 10.1124/jpet.111.181016] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
By repressing inflammatory gene expression, glucocorticoids are the most effective treatment for chronic inflammatory diseases such as asthma. However, in some patients with severe disease, or who smoke or suffer from chronic obstructive pulmonary disease, glucocorticoids are poorly effective. Although many investigators focus on defects in the repression of inflammatory gene expression, glucocorticoids also induce (transactivate) the expression of numerous genes to elicit anti-inflammatory effects. Using human bronchial epithelial (BEAS-2B) and pulmonary (A549) cells, we show that cytokines [tumor necrosis factor α (TNFα) and interleukin 1β], mitogens [fetal calf serum (FCS) and phorbol ester], cigarette smoke, and a G(q)-linked G protein-coupled receptor agonist attenuate simple glucocorticoid response element (GRE)-dependent transcription. With TNFα and FCS, this effect was not overcome by increasing concentrations of dexamethasone, budesonide, or fluticasone propionate. Thus, the maximal ability of the glucocorticoid to promote GRE-dependent transcription was reduced, and this was shown additionally for the glucocorticoid-induced gene p57(KIP2). The long-acting β(2)-adrenoceptor agonists (LABAs) formoterol fumarate and salmeterol xinafoate enhanced simple GRE-dependent transcription to a level that could not be achieved by glucocorticoid alone. In the presence of TNFα or FCS, which repressed glucocorticoid responsiveness, these LABAs restored glucocorticoid-dependent transcription to levels that were achieved by glucocorticoid alone. Given the existence of genes, such as p57(KIP2), which may mediate anti-inflammatory actions of glucocorticoids, we propose that repression of transactivation represents a mechanism for glucocorticoid resistance and for understanding the clinical benefit of LABAs as an add-on therapy in asthma and chronic obstructive pulmonary disease.
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Affiliation(s)
- Christopher F Rider
- Airways Inflammation Research Group, Faculty of Medicine, University of Calgary, Calgary, Alberta, Canada
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Dual specificity phosphatase 1 regulates human inducible nitric oxide synthase expression by p38 MAP kinase. Mediators Inflamm 2011; 2011:127587. [PMID: 21547253 PMCID: PMC3086212 DOI: 10.1155/2011/127587] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2010] [Accepted: 02/15/2011] [Indexed: 01/12/2023] Open
Abstract
The role of dual specificity phosphatase 1 (DUSP1) in inducible nitric oxide synthase (iNOS) expression in A549 human pulmonary epithelial cells, J774 mouse macrophages and primary mouse bone marrow-derived macrophages (BMMs) was investigated. iNOS expression was induced by a cytokine mixture (TNF, IFNγ and IL-1β) in A549 cells and by LPS in J774 cells, and it was inhibited by p38 MAPK inhibitors SB202190 and BIRB 796. Stimulation with cytokine mixture or LPS enhanced also DUSP1 expression. Down-regulation of DUSP1 by siRNA increased p38 MAPK phosphorylation and iNOS expression in A549 and J774 cells. In addition, LPS-induced iNOS expression was enhanced in BMMs from DUSP1(−/−) mice as compared to that in BMMs from wild-type mice. The results indicate that DUSP1 suppresses iNOS expression by limiting p38 MAPK activity in human and mouse cells. Compounds that enhance DUSP1 expression or modulate its function may be beneficial in diseases complicated with increased iNOS-mediated NO production.
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Blaser C, Wittwer M, Grandgirard D, Leib SL. Adjunctive dexamethasone affects the expression of genes related to inflammation, neurogenesis and apoptosis in infant rat pneumococcal meningitis. PLoS One 2011; 6:e17840. [PMID: 21412436 PMCID: PMC3055894 DOI: 10.1371/journal.pone.0017840] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2010] [Accepted: 02/15/2011] [Indexed: 12/20/2022] Open
Abstract
Streptococcus pneumoniae is the most common pathogen causing non-epidemic bacterial meningitis worldwide. The immune response and inflammatory processes contribute to the pathophysiology. Hence, the anti-inflammatory dexamethasone is advocated as adjuvant treatment although its clinical efficacy remains a question at issue. In experimental models of pneumococcal meningitis, dexamethasone increased neuronal damage in the dentate gyrus. Here, we investigated expressional changes in the hippocampus and cortex at 72 h after infection when dexamethasone was given to infant rats with pneumococcal meningitis. Nursing Wistar rats were intracisternally infected with Streptococcus pneumoniae to induce experimental meningitis or were sham-infected with pyrogen-free saline. Besides antibiotics, animals were either treated with dexamethasone or saline. Expressional changes were assessed by the use of GeneChip® Rat Exon 1.0 ST Arrays and quantitative real-time PCR. Protein levels of brain-derived neurotrophic factor, cytokines and chemokines were evaluated in immunoassays using Luminex xMAP® technology. In infected animals, 213 and 264 genes were significantly regulated by dexamethasone in the hippocampus and cortex respectively. Separately for the cortex and the hippocampus, Gene Ontology analysis identified clusters of biological processes which were assigned to the predefined categories "inflammation", "growth", "apoptosis" and others. Dexamethasone affected the expression of genes and protein levels of chemokines reflecting diminished activation of microglia. Dexamethasone-induced changes of genes related to apoptosis suggest the downregulation of the Akt-survival pathway and the induction of caspase-independent apoptosis. Signalling of pro-neurogenic pathways such as transforming growth factor pathway was reduced by dexamethasone resulting in a lack of pro-survival triggers. The anti-inflammatory properties of dexamethasone were observed on gene and protein level in experimental pneumococcal meningitis. Further dexamethasone-induced expressional changes reflect an increase of pro-apoptotic signals and a decrease of pro-neurogenic processes. The findings may help to identify potential mechanisms leading to apoptosis by dexamethasone in experimental pneumococcal meningitis.
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Affiliation(s)
- Cornelia Blaser
- Institute for Infectious Diseases, University of Bern, Bern, Switzerland
| | | | - Denis Grandgirard
- Institute for Infectious Diseases, University of Bern, Bern, Switzerland
| | - Stephen L. Leib
- Institute for Infectious Diseases, University of Bern, Bern, Switzerland
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Nicoletti-Carvalho JE, Lellis-Santos C, Yamanaka TS, Nogueira TC, Caperuto LC, Leite AR, Anhê GF, Bordin S. MKP-1 mediates glucocorticoid-induced ERK1/2 dephosphorylation and reduction in pancreatic ß-cell proliferation in islets from early lactating mothers. Am J Physiol Endocrinol Metab 2010; 299:E1006-15. [PMID: 20858750 DOI: 10.1152/ajpendo.00341.2010] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Maternal pancreatic islets undergo a robust increase of mass and proliferation during pregnancy, which allows a compensation of gestational insulin resistance. Studies have described that this adaptation switches to a low proliferative status after the delivery. The mechanisms underlying this reversal are unknown, but the action of glucocorticoids (GCs) is believed to play an important role because GCs counteract the pregnancy-like effects of PRL on isolated pancreatic islets maintained in cell culture. Here, we demonstrate that ERK1/2 phosphorylation (phospho-ERK1/2) is increased in maternal rat islets isolated on the 19th day of pregnancy. Phospho-ERK1/2 status on the 3rd day after delivery (L3) rapidly turns to values lower than that found in virgin control rats (CTL). MKP-1, a protein phosphatase able to dephosphorylate ERK1/2, is increased in islets from L3 rats. Chromatin immunoprecipitation assay revealed that binding of glucocorticoid receptor (GR) to MKP-1 promoter is also increased in islets from L3 rats. In addition, dexamethasone (DEX) reduced phospho-ERK1/2 and increased MKP-1 expression in RINm5F and MIN-6 cells. Inhibition of transduction with cycloheximide and inhibition of phosphatases with orthovanadate efficiently blocked DEX-induced downregulation of phospho-ERK1/2. In addition, specific knockdown of MKP-1 with siRNA suppressed the downregulation of phospho-ERK1/2 and the reduction of proliferation induced by DEX. Altogether, our results indicate that downregulation of phospho-ERK1/2 is associated with reduction in proliferation found in islets of early lactating mothers. This mechanism is probably mediated by GC-induced MKP-1 expression.
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