1
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Krontira AC, Cruceanu C, Dony L, Kyrousi C, Link MH, Rek N, Pöhlchen D, Raimundo C, Penner-Goeke S, Schowe A, Czamara D, Lahti-Pulkkinen M, Sammallahti S, Wolford E, Heinonen K, Roeh S, Sportelli V, Wölfel B, Ködel M, Sauer S, Rex-Haffner M, Räikkönen K, Labeur M, Cappello S, Binder EB. Human cortical neurogenesis is altered via glucocorticoid-mediated regulation of ZBTB16 expression. Neuron 2024; 112:1426-1443.e11. [PMID: 38442714 DOI: 10.1016/j.neuron.2024.02.005] [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: 01/17/2023] [Revised: 08/15/2023] [Accepted: 02/06/2024] [Indexed: 03/07/2024]
Abstract
Glucocorticoids are important for proper organ maturation, and their levels are tightly regulated during development. Here, we use human cerebral organoids and mice to study the cell-type-specific effects of glucocorticoids on neurogenesis. We show that glucocorticoids increase a specific type of basal progenitors (co-expressing PAX6 and EOMES) that has been shown to contribute to cortical expansion in gyrified species. This effect is mediated via the transcription factor ZBTB16 and leads to increased production of neurons. A phenome-wide Mendelian randomization analysis of an enhancer variant that moderates glucocorticoid-induced ZBTB16 levels reveals causal relationships with higher educational attainment and altered brain structure. The relationship with postnatal cognition is also supported by data from a prospective pregnancy cohort study. This work provides a cellular and molecular pathway for the effects of glucocorticoids on human neurogenesis that relates to lasting postnatal phenotypes.
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Affiliation(s)
- Anthi C Krontira
- Department Genes and Environment, Max Planck Institute of Psychiatry, Munich 80804, Germany; International Max Planck Research School for Translational Psychiatry, Munich 80804, Germany.
| | - Cristiana Cruceanu
- Department Genes and Environment, Max Planck Institute of Psychiatry, Munich 80804, Germany; Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm 17177, Sweden
| | - Leander Dony
- Department Genes and Environment, Max Planck Institute of Psychiatry, Munich 80804, Germany; International Max Planck Research School for Translational Psychiatry, Munich 80804, Germany; Department for Computational Health, Helmholtz Munich, Neuherberg 85764, Germany; TUM School of Life Sciences Weihenstephan, Technical University of Munich, Freising 85354, Germany
| | - Christina Kyrousi
- Developmental Neurobiology, Max Planck Institute of Psychiatry, Munich 80804, Germany; First Department of Psychiatry, Medical School, National and Kapodistrian University of Athens, Eginition Hospital, Athens 15784, Greece; University Mental Health, Neurosciences and Precision Medicine Research Institute "Costas Stefanis", Athens 15601, Greece
| | - Marie-Helen Link
- Department Genes and Environment, Max Planck Institute of Psychiatry, Munich 80804, Germany
| | - Nils Rek
- Department Genes and Environment, Max Planck Institute of Psychiatry, Munich 80804, Germany; International Max Planck Research School for Translational Psychiatry, Munich 80804, Germany
| | - Dorothee Pöhlchen
- Department Genes and Environment, Max Planck Institute of Psychiatry, Munich 80804, Germany; International Max Planck Research School for Translational Psychiatry, Munich 80804, Germany
| | - Catarina Raimundo
- Department Genes and Environment, Max Planck Institute of Psychiatry, Munich 80804, Germany
| | - Signe Penner-Goeke
- Department Genes and Environment, Max Planck Institute of Psychiatry, Munich 80804, Germany
| | - Alicia Schowe
- Department Genes and Environment, Max Planck Institute of Psychiatry, Munich 80804, Germany; Graduate School of Systemic Neurosciences, Ludwig-Maximilians-University, Munich 82152, Germany
| | - Darina Czamara
- Department Genes and Environment, Max Planck Institute of Psychiatry, Munich 80804, Germany
| | - Marius Lahti-Pulkkinen
- Department of Psychology and Logopedics, Faculty of Medicine, University of Helsinki, Helsinki 00014, Finland; Finnish Institute for Health and Welfare, Helsinki 00271, Finland; Centre for Cardiovascular Science, Queen's Medical Research Institute, University of Edinburgh, Edinburgh EH16 4TJ, UK
| | - Sara Sammallahti
- Department of Obstetrics and Gynecology, Helsinki University Hospital and University of Helsinki, Helsinki 00014, Finland
| | - Elina Wolford
- Department of Psychology and Logopedics, Faculty of Medicine, University of Helsinki, Helsinki 00014, Finland
| | - Kati Heinonen
- Department of Psychology and Logopedics, Faculty of Medicine, University of Helsinki, Helsinki 00014, Finland; Psychology/Welfare, Faculty of Social Sciences, University of Tampere, Tampere 33014, Finland; Lawrence S. Bloomberg Faculty of Nursing, University of Toronto, Toronto, ON M5T 1P8, Canada
| | - Simone Roeh
- Department Genes and Environment, Max Planck Institute of Psychiatry, Munich 80804, Germany
| | - Vincenza Sportelli
- Department Genes and Environment, Max Planck Institute of Psychiatry, Munich 80804, Germany
| | - Barbara Wölfel
- Department Genes and Environment, Max Planck Institute of Psychiatry, Munich 80804, Germany
| | - Maik Ködel
- Department Genes and Environment, Max Planck Institute of Psychiatry, Munich 80804, Germany
| | - Susann Sauer
- Department Genes and Environment, Max Planck Institute of Psychiatry, Munich 80804, Germany
| | - Monika Rex-Haffner
- Department Genes and Environment, Max Planck Institute of Psychiatry, Munich 80804, Germany
| | - Katri Räikkönen
- Department of Psychology and Logopedics, Faculty of Medicine, University of Helsinki, Helsinki 00014, Finland
| | - Marta Labeur
- Department Genes and Environment, Max Planck Institute of Psychiatry, Munich 80804, Germany
| | - Silvia Cappello
- Developmental Neurobiology, Max Planck Institute of Psychiatry, Munich 80804, Germany; Physiological Genomics, Biomedical Center (BMC), Faculty of Medicine, Ludwig-Maximilians-University (LMU), Munich 82152, Germany
| | - Elisabeth B Binder
- Department Genes and Environment, Max Planck Institute of Psychiatry, Munich 80804, Germany.
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2
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Martinez GJ, Appleton M, Kipp ZA, Loria AS, Min B, Hinds TD. Glucocorticoids, their uses, sexual dimorphisms, and diseases: new concepts, mechanisms, and discoveries. Physiol Rev 2024; 104:473-532. [PMID: 37732829 DOI: 10.1152/physrev.00021.2023] [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: 05/22/2023] [Revised: 08/07/2023] [Accepted: 09/10/2023] [Indexed: 09/22/2023] Open
Abstract
The normal stress response in humans is governed by the hypothalamic-pituitary-adrenal (HPA) axis through heightened mechanisms during stress, raising blood levels of the glucocorticoid hormone cortisol. Glucocorticoids are quintessential compounds that balance the proper functioning of numerous systems in the mammalian body. They are also generated synthetically and are the preeminent therapy for inflammatory diseases. They act by binding to the nuclear receptor transcription factor glucocorticoid receptor (GR), which has two main isoforms (GRα and GRβ). Our classical understanding of glucocorticoid signaling is from the GRα isoform, which binds the hormone, whereas GRβ has no known ligands. With glucocorticoids being involved in many physiological and cellular processes, even small disruptions in their release via the HPA axis, or changes in GR isoform expression, can have dire ramifications on health. Long-term chronic glucocorticoid therapy can lead to a glucocorticoid-resistant state, and we deliberate how this impacts disease treatment. Chronic glucocorticoid treatment can lead to noticeable side effects such as weight gain, adiposity, diabetes, and others that we discuss in detail. There are sexually dimorphic responses to glucocorticoids, and women tend to have a more hyperresponsive HPA axis than men. This review summarizes our understanding of glucocorticoids and critically analyzes the GR isoforms and their beneficial and deleterious mechanisms and the sexual differences that cause a dichotomy in responses. We also discuss the future of glucocorticoid therapy and propose a new concept of dual GR isoform agonist and postulate why activating both isoforms may prevent glucocorticoid resistance.
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Affiliation(s)
- Genesee J Martinez
- Department of Pharmacology and Nutritional Sciences, University of Kentucky College of Medicine, Lexington, Kentucky, United States
| | - Malik Appleton
- Department of Pharmacology and Nutritional Sciences, University of Kentucky College of Medicine, Lexington, Kentucky, United States
| | - Zachary A Kipp
- Department of Pharmacology and Nutritional Sciences, University of Kentucky College of Medicine, Lexington, Kentucky, United States
| | - Analia S Loria
- Department of Pharmacology and Nutritional Sciences, University of Kentucky College of Medicine, Lexington, Kentucky, United States
- Barnstable Brown Diabetes Center, University of Kentucky College of Medicine, Lexington, Kentucky, United States
| | - Booki Min
- Department of Microbiology and Immunology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, United States
| | - Terry D Hinds
- Department of Pharmacology and Nutritional Sciences, University of Kentucky College of Medicine, Lexington, Kentucky, United States
- Barnstable Brown Diabetes Center, University of Kentucky College of Medicine, Lexington, Kentucky, United States
- Markey Cancer Center, University of Kentucky, Lexington, Kentucky, United States
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3
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Pofi R, Caratti G, Ray DW, Tomlinson JW. Treating the Side Effects of Exogenous Glucocorticoids; Can We Separate the Good From the Bad? Endocr Rev 2023; 44:975-1011. [PMID: 37253115 PMCID: PMC10638606 DOI: 10.1210/endrev/bnad016] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Revised: 04/25/2023] [Accepted: 05/26/2023] [Indexed: 06/01/2023]
Abstract
It is estimated that 2% to 3% of the population are currently prescribed systemic or topical glucocorticoid treatment. The potent anti-inflammatory action of glucocorticoids to deliver therapeutic benefit is not in doubt. However, the side effects associated with their use, including central weight gain, hypertension, insulin resistance, type 2 diabetes (T2D), and osteoporosis, often collectively termed iatrogenic Cushing's syndrome, are associated with a significant health and economic burden. The precise cellular mechanisms underpinning the differential action of glucocorticoids to drive the desirable and undesirable effects are still not completely understood. Faced with the unmet clinical need to limit glucocorticoid-induced adverse effects alongside ensuring the preservation of anti-inflammatory actions, several strategies have been pursued. The coprescription of existing licensed drugs to treat incident adverse effects can be effective, but data examining the prevention of adverse effects are limited. Novel selective glucocorticoid receptor agonists and selective glucocorticoid receptor modulators have been designed that aim to specifically and selectively activate anti-inflammatory responses based upon their interaction with the glucocorticoid receptor. Several of these compounds are currently in clinical trials to evaluate their efficacy. More recently, strategies exploiting tissue-specific glucocorticoid metabolism through the isoforms of 11β-hydroxysteroid dehydrogenase has shown early potential, although data from clinical trials are limited. The aim of any treatment is to maximize benefit while minimizing risk, and within this review we define the adverse effect profile associated with glucocorticoid use and evaluate current and developing strategies that aim to limit side effects but preserve desirable therapeutic efficacy.
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Affiliation(s)
- Riccardo Pofi
- Oxford Centre for Diabetes, Endocrinology and Metabolism, NIHR Oxford Biomedical Research Centre, University of Oxford, Churchill Hospital, Oxford OX3 7LE, UK
| | - Giorgio Caratti
- Oxford Centre for Diabetes, Endocrinology and Metabolism, NIHR Oxford Biomedical Research Centre, University of Oxford, Churchill Hospital, Oxford OX3 7LE, UK
| | - David W Ray
- Oxford Centre for Diabetes, Endocrinology and Metabolism, NIHR Oxford Biomedical Research Centre, University of Oxford, Churchill Hospital, Oxford OX3 7LE, UK
- NIHR Oxford Biomedical Research Centre, John Radcliffe Hospital, Oxford OX3 9DU, UK
- Oxford Kavli Centre for Nanoscience Discovery, University of Oxford, Oxford OX37LE, UK
| | - Jeremy W Tomlinson
- Oxford Centre for Diabetes, Endocrinology and Metabolism, NIHR Oxford Biomedical Research Centre, University of Oxford, Churchill Hospital, Oxford OX3 7LE, UK
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Fadel L, Dacic M, Fonda V, Sokolsky BA, Quagliarini F, Rogatsky I, Uhlenhaut NH. Modulating glucocorticoid receptor actions in physiology and pathology: Insights from coregulators. Pharmacol Ther 2023; 251:108531. [PMID: 37717739 PMCID: PMC10841922 DOI: 10.1016/j.pharmthera.2023.108531] [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: 05/14/2023] [Revised: 09/11/2023] [Accepted: 09/13/2023] [Indexed: 09/19/2023]
Abstract
Glucocorticoids (GCs) are a class of steroid hormones that regulate key physiological processes such as metabolism, immune function, and stress responses. The effects of GCs are mediated by the glucocorticoid receptor (GR), a ligand-dependent transcription factor that activates or represses the expression of hundreds to thousands of genes in a tissue- and physiological state-specific manner. The activity of GR is modulated by numerous coregulator proteins that interact with GR in response to different stimuli assembling into a multitude of DNA-protein complexes and facilitate the integration of these signals, helping GR to communicate with basal transcriptional machinery and chromatin. Here, we provide a brief overview of the physiological and molecular functions of GR, and discuss the roles of GR coregulators in the immune system, key metabolic tissues and the central nervous system. We also present an analysis of the GR interactome in different cells and tissues, which suggests tissue-specific utilization of GR coregulators, despite widespread functions shared by some of them.
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Affiliation(s)
- Lina Fadel
- Institute for Diabetes and Endocrinology IDE, Helmholtz Munich, Ingolstaedter Landstr. 1, 857649 Neuherberg, Germany
| | - Marija Dacic
- Hospital for Special Surgery Research Institute, The David Rosenzweig Genomics Center, New York, NY, USA; Graduate Program in Physiology, Biophysics and Systems Biology, Weill Cornell Graduate School of Medical Sciences, New York, NY, USA
| | - Vlera Fonda
- Institute for Diabetes and Endocrinology IDE, Helmholtz Munich, Ingolstaedter Landstr. 1, 857649 Neuherberg, Germany
| | - Baila A Sokolsky
- Hospital for Special Surgery Research Institute, The David Rosenzweig Genomics Center, New York, NY, USA; Graduate Program in Immunology and Microbial Pathogenesis, Weill Cornell Graduate School of Medical Sciences, New York, NY, USA
| | - Fabiana Quagliarini
- Institute for Diabetes and Endocrinology IDE, Helmholtz Munich, Ingolstaedter Landstr. 1, 857649 Neuherberg, Germany
| | - Inez Rogatsky
- Hospital for Special Surgery Research Institute, The David Rosenzweig Genomics Center, New York, NY, USA; Graduate Program in Immunology and Microbial Pathogenesis, Weill Cornell Graduate School of Medical Sciences, New York, NY, USA.
| | - N Henriette Uhlenhaut
- Institute for Diabetes and Endocrinology IDE, Helmholtz Munich, Ingolstaedter Landstr. 1, 857649 Neuherberg, Germany; Metabolic Programming, TUM School of Life Sciences & ZIEL Institute for Food and Health, Gregor11 Mendel-Str. 2, 85354 Freising, Germany.
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5
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Hörberg J, Reymer A. Decoding the dual recognition mechanism of the glucocorticoid receptor for DNA and RNA: sequence versus shape. Sci Rep 2023; 13:16125. [PMID: 37752333 PMCID: PMC10522765 DOI: 10.1038/s41598-023-43244-1] [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: 03/03/2023] [Accepted: 09/21/2023] [Indexed: 09/28/2023] Open
Abstract
Transcription factors (TFs) regulate eukaryotic transcription through selective DNA-binding, can also specifically interact with RNA, which may present another layer of transcriptional control. The mechanisms of the TFs-DNA recognition are often well-characterised, while the details of TFs-RNA complexation are less understood. Here we investigate the dual recognition mechanism of the glucocorticoid receptor (GR), which interacts with similar affinities with consensus DNA and diverse RNA hairpin motifs but discriminates against uniform dsRNA. Using atomic molecular dynamics simulations, we demonstrate that the GR binding to nucleic acids requires a wide and shallow groove pocket. The protein effectively moulds its binding site within DNA major groove, which enables base-specific interactions. Contrary, the GR binding has little effect on the grooves geometry of RNA systems, most notably in uniform dsRNA. Instead, a hairpin motif in RNA yields a wide and shallow major groove pocket, allowing the protein to anchor itself through nonspecific electrostatic contacts with RNA backbone. Addition of a bulge increases RNA hairpin flexibility, which leads to a greater number of GR-RNA contacts and, thus, higher affinity. Thus, the combination of structural motifs defines the GR-RNA selective binding: a recognition mechanism, which may be shared by other zinc finger TFs.
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Affiliation(s)
- Johanna Hörberg
- Department of Chemistry and Molecular Biology, University of Gothenburg, 405 30, Göteborg, Sweden
| | - Anna Reymer
- Department of Chemistry and Molecular Biology, University of Gothenburg, 405 30, Göteborg, Sweden.
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6
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Lammer NC, Allen MA, Batey RT, Wuttke DS. Quantification of transcriptome changes to investigate the role of glucocorticoid receptor-RNA binding during dexamethasone treatment. BMC Res Notes 2023; 16:181. [PMID: 37608297 PMCID: PMC10464093 DOI: 10.1186/s13104-023-06446-4] [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: 11/23/2022] [Accepted: 07/31/2023] [Indexed: 08/24/2023] Open
Abstract
OBJECTIVES The glucocorticoid receptor (GR) is a well-studied, ligand-activated transcription factor and a common target of anti-inflammatory treatments. Recently, several studies have drawn attention the effects of binding of GR to RNA rather than DNA and the potential implications of this activity for GR function. The objective of our study was to further characterize the relationship between GR function and RNA binding by measuring changes in the glucocorticoid-driven transcriptome in the presence of a GR mutant that exhibited reduced RNA affinity. DATA DESCRIPTION GR was activated in three cell lines containing GR constructs (GR-HaloTag). One of the cell lines contained a wild-type GR-HaloTag. Another contained GR-HaloTag with a mutation that reduced RNA affinity and slightly reduced DNA affinity. The third cell line contained GR-HaloTag with a mutation that only slightly reduced DNA affinity. All three cell lines were treated with dexamethasone, a GR agonist. RNA-seq samples were collected every hour for 3 h. Moreover, transcriptome quantification was accomplished via labeling of RNAs transcribed in the final hour of dexamethasone treatment using 4-thiouridine. These labeled RNAs were then purified and sequenced. This data set is the first of its kind for GR and contains valuable insights into the function of RNA binding by GR.
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Affiliation(s)
- Nickolaus C Lammer
- Department of Biochemistry, University of Colorado at Boulder, Campus Box 596, Boulder, CO, 80309-0596, USA
| | - Mary A Allen
- BioFrontiers Institute, University of Colorado at Boulder, Campus Box 596, Boulder, CO, 80309-0596, USA
| | - Robert T Batey
- Department of Biochemistry, University of Colorado at Boulder, Campus Box 596, Boulder, CO, 80309-0596, USA.
| | - Deborah S Wuttke
- Department of Biochemistry, University of Colorado at Boulder, Campus Box 596, Boulder, CO, 80309-0596, USA.
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7
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Deploey N, Van Moortel L, Rogatsky I, Peelman F, De Bosscher K. The Biologist's Guide to the Glucocorticoid Receptor's Structure. Cells 2023; 12:1636. [PMID: 37371105 PMCID: PMC10297449 DOI: 10.3390/cells12121636] [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: 05/09/2023] [Revised: 06/07/2023] [Accepted: 06/09/2023] [Indexed: 06/29/2023] Open
Abstract
The glucocorticoid receptor α (GRα) is a member of the nuclear receptor superfamily and functions as a glucocorticoid (GC)-responsive transcription factor. GR can halt inflammation and kill off cancer cells, thus explaining the widespread use of glucocorticoids in the clinic. However, side effects and therapy resistance limit GR's therapeutic potential, emphasizing the importance of resolving all of GR's context-specific action mechanisms. Fortunately, the understanding of GR structure, conformation, and stoichiometry in the different GR-controlled biological pathways is now gradually increasing. This information will be crucial to close knowledge gaps on GR function. In this review, we focus on the various domains and mechanisms of action of GR, all from a structural perspective.
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Affiliation(s)
- Nick Deploey
- VIB Center for Medical Biotechnology, VIB, 9052 Ghent, Belgium; (N.D.); (L.V.M.); (F.P.)
- Department of Biomolecular Medicine, Ghent University, 9000 Ghent, Belgium
- Translational Nuclear Receptor Research (TNRR) Laboratory, VIB, 9052 Ghent, Belgium
| | - Laura Van Moortel
- VIB Center for Medical Biotechnology, VIB, 9052 Ghent, Belgium; (N.D.); (L.V.M.); (F.P.)
- Department of Biomolecular Medicine, Ghent University, 9000 Ghent, Belgium
- Translational Nuclear Receptor Research (TNRR) Laboratory, VIB, 9052 Ghent, Belgium
| | - Inez Rogatsky
- Hospital for Special Surgery Research Institute, The David Z. Rosensweig Genomics Center, New York, NY 10021, USA;
- Graduate Program in Immunology and Microbial Pathogenesis, Weill Cornell Graduate School of Medical Sciences, New York, NY 10065, USA
| | - Frank Peelman
- VIB Center for Medical Biotechnology, VIB, 9052 Ghent, Belgium; (N.D.); (L.V.M.); (F.P.)
- Department of Biomolecular Medicine, Ghent University, 9000 Ghent, Belgium
| | - Karolien De Bosscher
- VIB Center for Medical Biotechnology, VIB, 9052 Ghent, Belgium; (N.D.); (L.V.M.); (F.P.)
- Department of Biomolecular Medicine, Ghent University, 9000 Ghent, Belgium
- Translational Nuclear Receptor Research (TNRR) Laboratory, VIB, 9052 Ghent, Belgium
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8
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Lammer NC, Ashraf HM, Ugay DA, Spencer SL, Allen MA, Batey RT, Wuttke DS. RNA binding by the glucocorticoid receptor attenuates dexamethasone-induced gene activation. Sci Rep 2023; 13:9385. [PMID: 37296231 PMCID: PMC10251336 DOI: 10.1038/s41598-023-35549-y] [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: 12/14/2022] [Accepted: 05/19/2023] [Indexed: 06/12/2023] Open
Abstract
The glucocorticoid receptor (GR) is a ligand-activated transcription factor that regulates a suite of genes through direct binding of GR to specific DNA promoter elements. GR also interacts with RNA, but the function of this RNA-binding activity remains elusive. Current models speculate that RNA could repress the transcriptional activity of GR. To investigate the function of the GR-RNA interaction on GR's transcriptional activity, we generated cells that stably express a mutant of GR with reduced RNA binding affinity and treated the cells with the GR agonist dexamethasone. Changes in the dexamethasone-driven transcriptome were quantified using 4-thiouridine labeling of RNAs followed by high-throughput sequencing. We find that while many genes are unaffected, GR-RNA binding is repressive for specific subsets of genes in both dexamethasone-dependent and independent contexts. Genes that are dexamethasone-dependent are activated directly by chromatin-bound GR, suggesting a competition-based repression mechanism in which increasing local concentrations of RNA may compete with DNA for binding to GR at sites of transcription. Unexpectedly, genes that are dexamethasone-independent instead display a localization to specific chromosomal regions, which points to changes in chromatin accessibility or architecture. These results show that RNA binding plays a fundamental role in regulating GR function and highlights potential functions for transcription factor-RNA interactions.
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Affiliation(s)
- Nickolaus C Lammer
- Department of Biochemistry, University of Colorado, Boulder, CO, 80309, USA
| | - Humza M Ashraf
- Department of Biochemistry, University of Colorado, Boulder, CO, 80309, USA
| | - Daniella A Ugay
- Department of Biochemistry, University of Colorado, Boulder, CO, 80309, USA
| | - Sabrina L Spencer
- Department of Biochemistry, University of Colorado, Boulder, CO, 80309, USA
- BioFrontiers Institute, University of Colorado, Boulder, CO, 80309, USA
| | - Mary A Allen
- BioFrontiers Institute, University of Colorado, Boulder, CO, 80309, USA
| | - Robert T Batey
- Department of Biochemistry, University of Colorado, Boulder, CO, 80309, USA.
| | - Deborah S Wuttke
- Department of Biochemistry, University of Colorado, Boulder, CO, 80309, USA.
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9
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Alexandari AM, Horton CA, Shrikumar A, Shah N, Li E, Weilert M, Pufall MA, Zeitlinger J, Fordyce PM, Kundaje A. De novo distillation of thermodynamic affinity from deep learning regulatory sequence models of in vivo protein-DNA binding. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.11.540401. [PMID: 37214836 PMCID: PMC10197627 DOI: 10.1101/2023.05.11.540401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Transcription factors (TF) are proteins that bind DNA in a sequence-specific manner to regulate gene transcription. Despite their unique intrinsic sequence preferences, in vivo genomic occupancy profiles of TFs differ across cellular contexts. Hence, deciphering the sequence determinants of TF binding, both intrinsic and context-specific, is essential to understand gene regulation and the impact of regulatory, non-coding genetic variation. Biophysical models trained on in vitro TF binding assays can estimate intrinsic affinity landscapes and predict occupancy based on TF concentration and affinity. However, these models cannot adequately explain context-specific, in vivo binding profiles. Conversely, deep learning models, trained on in vivo TF binding assays, effectively predict and explain genomic occupancy profiles as a function of complex regulatory sequence syntax, albeit without a clear biophysical interpretation. To reconcile these complementary models of in vitro and in vivo TF binding, we developed Affinity Distillation (AD), a method that extracts thermodynamic affinities de-novo from deep learning models of TF chromatin immunoprecipitation (ChIP) experiments by marginalizing away the influence of genomic sequence context. Applied to neural networks modeling diverse classes of yeast and mammalian TFs, AD predicts energetic impacts of sequence variation within and surrounding motifs on TF binding as measured by diverse in vitro assays with superior dynamic range and accuracy compared to motif-based methods. Furthermore, AD can accurately discern affinities of TF paralogs. Our results highlight thermodynamic affinity as a key determinant of in vivo binding, suggest that deep learning models of in vivo binding implicitly learn high-resolution affinity landscapes, and show that these affinities can be successfully distilled using AD. This new biophysical interpretation of deep learning models enables high-throughput in silico experiments to explore the influence of sequence context and variation on both intrinsic affinity and in vivo occupancy.
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Affiliation(s)
- Amr M. Alexandari
- Department of Computer Science, Stanford University, Stanford, CA 94305
| | | | - Avanti Shrikumar
- Department of Earth System Science, Stanford University, Stanford, CA 94305
| | - Nilay Shah
- Stowers Institute for Medical Research, Kansas City, MO, USA
| | - Eileen Li
- Department of Genetics, Stanford University, Stanford, CA 94305
| | - Melanie Weilert
- Stowers Institute for Medical Research, Kansas City, MO, USA
| | - Miles A. Pufall
- Department of Biochemistry, Carver College of Medicine, University of Iowa, Iowa City, Iowa 52242, USA
| | - Julia Zeitlinger
- Stowers Institute for Medical Research, Kansas City, MO, USA
- The University of Kansas Medical Center, Kansas City, KS, USA
| | - Polly M. Fordyce
- Department of Genetics, Stanford University, Stanford, CA 94305
- Department of Bioengineering, Stanford University, Stanford, CA 94305
- ChEM-H Institute, Stanford University, Stanford, CA 94305
- Chan Zuckerberg Biohub, San Francisco, CA 94110
| | - Anshul Kundaje
- Department of Computer Science, Stanford University, Stanford, CA 94305
- Department of Genetics, Stanford University, Stanford, CA 94305
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10
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Langgartner D, Koenen M, Kupfer S, Glogger L, Kurz L, Perez-Rivas LG, Theodoropoulou M, Noll-Hussong M, Vettorazzi S, Tuckermann J, Reber SO. Intact GR dimerization is critical for restraining plasma ACTH levels during chronic psychosocial stress. Neurobiol Stress 2023; 24:100541. [PMID: 37215522 PMCID: PMC10196852 DOI: 10.1016/j.ynstr.2023.100541] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Revised: 04/13/2023] [Accepted: 04/25/2023] [Indexed: 05/24/2023] Open
Abstract
Male C57BL/6N mice exposed to the chronic subordinate colony housing (CSC; 19 days) paradigm, a preclinically validated model of chronic psychosocial stress, are characterized by unaffected basal morning plasma corticosterone (CORT) concentrations despite adrenal and pituitary hyperplasia and increased adrenocorticotropic hormone (ACTH) plasma concentrations, compared with single-housed control (SHC) mice. However, as CSC mice are still able to show an increased CORT secretion towards novel heterotypic stressors, these effects might reflect an adaptation rather than a functional breakdown of general hypothalamus-pituitary-adrenal (HPA) axis functionality. In the present study we used male mice of a genetically modified mouse line, to investigate whether genetically-driven ACTH overexpression compromises adaptational processes occurring at the level of the adrenals during CSC exposure. Experimental mice carried a point mutation in the DNA binding domain of the glucocorticoid (GC) receptor (GR), attenuating dimerization of GR (GRdim), resulting in a congenially compromised negative feedback inhibition at the level of the pituitary. In line with previous studies, CSC mice in both the wild type (WT; GR+/+) and GRdim group developed adrenal enlargement. Moreover, compared with respective SHC and WT mice, CSC GRdim mice show increased basal morning plasma ACTH and CORT concentrations. Quantitative polymerase chain reaction (qPCR) analysis revealed neither a genotype effect, nor a CSC effect on pituitary mRNA expression of the ACTH precursor proopiomelanocortin (POMC). Finally, CSC increased anxiety-related behavior, active coping and splenocyte in vitro (re)activity in both WT and GRdim mice, while a CSC-induced increase in adrenal lipid vesicles and splenic GC resistance was detectable only in WT mice. Of note, lipopolysaccharide (LPS)-stimulated splenocytes of GRdim mice were resistant to the inhibitory effects of CORT. Together our findings support the hypothesis that pituitary ACTH protein concentration is negatively controlled by GR dimerization under conditions of chronic psychosocial stress, while POMC gene transcription is not dependent on intact GR dimerization under both basal and chronic stress conditions. Finally, our data suggest that adrenal adaptations during chronic psychosocial stress (i.e., ACTH desensitization), aiming at the prevention of prolonged hypercorticism, are protective only to a certain threshold of plasma ACTH levels.
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Affiliation(s)
- Dominik Langgartner
- Laboratory for Molecular Psychosomatics, Department of Psychosomatic Medicine and Psychotherapy, Ulm University Medical Center, Ulm, Germany
| | - Mascha Koenen
- Institute of Comparative Molecular Endocrinology, University Ulm, Ulm, Germany
| | - Sandra Kupfer
- Laboratory for Molecular Psychosomatics, Department of Psychosomatic Medicine and Psychotherapy, Ulm University Medical Center, Ulm, Germany
| | - Lisa Glogger
- Laboratory for Molecular Psychosomatics, Department of Psychosomatic Medicine and Psychotherapy, Ulm University Medical Center, Ulm, Germany
| | - Lisa Kurz
- Laboratory for Molecular Psychosomatics, Department of Psychosomatic Medicine and Psychotherapy, Ulm University Medical Center, Ulm, Germany
| | - Luis Gustavo Perez-Rivas
- Medical Clinic and Polyclinic IV, LMU Clinic, Ludwig-Maximilian-University Munich, Munich, Germany
| | - Marily Theodoropoulou
- Medical Clinic and Polyclinic IV, LMU Clinic, Ludwig-Maximilian-University Munich, Munich, Germany
| | - Michael Noll-Hussong
- Psychosomatic Medicine and Psychotherapy, Saarland University Medical Centre, Homburg, Germany
| | - Sabine Vettorazzi
- Institute of Comparative Molecular Endocrinology, University Ulm, Ulm, Germany
| | - Jan Tuckermann
- Institute of Comparative Molecular Endocrinology, University Ulm, Ulm, Germany
| | - Stefan O. Reber
- Laboratory for Molecular Psychosomatics, Department of Psychosomatic Medicine and Psychotherapy, Ulm University Medical Center, Ulm, Germany
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11
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Santos VC, Ostler JB, Harrison KS, Jones C. Slug, a Stress-Induced Transcription Factor, Stimulates Herpes Simplex Virus 1 Replication and Transactivates a cis-Regulatory Module within the VP16 Promoter. J Virol 2023; 97:e0007323. [PMID: 37022165 PMCID: PMC10134811 DOI: 10.1128/jvi.00073-23] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Accepted: 03/16/2023] [Indexed: 04/07/2023] Open
Abstract
Stress-mediated activation of the glucocorticoid receptor (GR) and specific stress-induced transcription factors stimulate herpes simplex virus 1 (HSV-1) productive infection, explant-induced reactivation, and immediate early (IE) promoters that drive expression of infected cell protein 0 (ICP0), ICP4, and ICP27. Several published studies concluded the virion tegument protein VP16, ICP0, and/or ICP4 drives early steps of reactivation from latency. Notably, VP16 protein expression was induced in trigeminal ganglionic neurons of Swiss Webster or C57BL/6J mice during early stages of stress-induced reactivation. If VP16 mediates reactivation, we hypothesized stress-induced cellular transcription factors would stimulate its expression. To address this hypothesis, we tested whether stress-induced transcription factors transactivate a VP16 cis-regulatory module (CRM) located upstream of the VP16 TATA box (-249 to -30). Initial studies revealed the VP16 CRM cis-activated a minimal promoter more efficiently in mouse neuroblastoma cells (Neuro-2A) than mouse fibroblasts (NIH-3T3). GR and Slug, a stress-induced transcription factor that binds enhancer boxes (E-boxes), were the only stress-induced transcription factors examined that transactivated the VP16 CRM construct. GR- and Slug-mediated transactivation was reduced to basal levels when the E-box, two 1/2 GR response elements (GREs), or NF-κB binding site was mutated. Previous studies revealed GR and Slug cooperatively transactivated the ICP4 CRM, but not ICP0 or ICP27. Silencing of Slug expression in Neuro-2A cells significantly reduced viral replication, indicating Slug-mediated transactivation of ICP4 and VP16 CRM activity correlates with enhanced viral replication and reactivation from latency. IMPORTANCE Herpes simplex virus 1 (HSV-1) establishes lifelong latency in several types of neurons. Periodically cellular stressors trigger reactivation from latency. Viral regulatory proteins are not abundantly expressed during latency, indicating cellular transcription factors mediate early stages of reactivation. Notably, the glucocorticoid receptor (GR) and certain stress-induced transcription factors transactivate cis-regulatory modules (CRMs) essential for expression of infected cell protein 0 (ICP0) and ICP4, key viral transcriptional regulatory proteins linked to triggering reactivation from latency. Virion protein 16 (VP16) specifically transactivates IE promoter and was also reported to mediate early stages of reactivation from latency. GR and Slug, a stress-induced enhancer box (E-box) binding protein, transactivate a minimal promoter downstream of VP16 CRM, and these transcription factors occupy VP16 CRM sequences in transfected cells. Notably, Slug stimulates viral replication in mouse neuroblastoma cells suggesting Slug, by virtue of transactivating VP16 and ICP4 CRM sequences, can trigger reactivation in certain neurons.
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Affiliation(s)
- Vanessa Claire Santos
- Oklahoma State University, College of Veterinary Medicine, Department of Veterinary Pathobiology, Stillwater, Oklahoma, USA
| | - Jeffery B. Ostler
- Oklahoma State University, College of Veterinary Medicine, Department of Veterinary Pathobiology, Stillwater, Oklahoma, USA
| | - Kelly S. Harrison
- Oklahoma State University, College of Veterinary Medicine, Department of Veterinary Pathobiology, Stillwater, Oklahoma, USA
| | - Clinton Jones
- Oklahoma State University, College of Veterinary Medicine, Department of Veterinary Pathobiology, Stillwater, Oklahoma, USA
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12
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Postel S, Wissler L, Johansson CA, Gunnarsson A, Gordon E, Collins B, Castaldo M, Köhler C, Öling D, Johansson P, Fröderberg Roth L, Beinsteiner B, Dainty I, Delaney S, Klaholz BP, Billas IML, Edman K. Quaternary glucocorticoid receptor structure highlights allosteric interdomain communication. Nat Struct Mol Biol 2023; 30:286-295. [PMID: 36747092 DOI: 10.1038/s41594-022-00914-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Accepted: 12/15/2022] [Indexed: 02/08/2023]
Abstract
The glucocorticoid receptor (GR) is a ligand-activated transcription factor that binds DNA and assembles co-regulator complexes to regulate gene transcription. GR agonists are widely prescribed to people with inflammatory and autoimmune diseases. Here we present high-resolution, multidomain structures of GR in complex with ligand, DNA and co-regulator peptide. The structures reveal how the receptor forms an asymmetric dimer on the DNA and provide a detailed view of the domain interactions within and across the two monomers. Hydrogen-deuterium exchange and DNA-binding experiments demonstrate that ligand-dependent structural changes are communicated across the different domains in the full-length receptor. This study demonstrates how GR forms a distinct architecture on DNA and how signal transmission can be modulated by the ligand pharmacophore, provides a platform to build a new level of understanding of how receptor modifications can drive disease progression and offers key insight for future drug design.
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Affiliation(s)
- Sandra Postel
- Mechanistic & Structural Biology, Discovery Sciences, R&D, AstraZeneca, Gothenburg, Sweden
| | - Lisa Wissler
- Mechanistic & Structural Biology, Discovery Sciences, R&D, AstraZeneca, Gothenburg, Sweden
| | - Carina A Johansson
- Mechanistic & Structural Biology, Discovery Sciences, R&D, AstraZeneca, Gothenburg, Sweden
| | - Anders Gunnarsson
- Mechanistic & Structural Biology, Discovery Sciences, R&D, AstraZeneca, Gothenburg, Sweden
| | - Euan Gordon
- Discovery Biology, Discovery Sciences, R&D, AstraZeneca, Gothenburg, Sweden
| | - Barry Collins
- Bioscience COPD/IPF, Research and Early Development, Respiratory and Immunology (R&I), BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Marie Castaldo
- Discovery Biology, Discovery Sciences, R&D, AstraZeneca, Gothenburg, Sweden
| | - Christian Köhler
- Bioscience COPD/IPF, Research and Early Development, Respiratory and Immunology (R&I), BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - David Öling
- Discovery Biology, Discovery Sciences, R&D, AstraZeneca, Gothenburg, Sweden
| | - Patrik Johansson
- Mechanistic & Structural Biology, Discovery Sciences, R&D, AstraZeneca, Gothenburg, Sweden
| | | | - Brice Beinsteiner
- Centre for Integrative Biology (CBI), Department of Integrated Structural Biology, Institute of Genetics and of Molecular and Cellular Biology (IGBMC), Illkirch, France
- Université de Strasbourg, Illkirch, France
- Institut National de la Santé et de la Recherche Médicale (INSERM), Illkirch, France
- Centre National de la Recherche Scientifique (CNRS) UMR 7104, Illkirch, France
| | - Ian Dainty
- Bioscience COPD/IPF, Research and Early Development, Respiratory and Immunology (R&I), BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Stephen Delaney
- Bioscience COPD/IPF, Research and Early Development, Respiratory and Immunology (R&I), BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Bruno P Klaholz
- Centre for Integrative Biology (CBI), Department of Integrated Structural Biology, Institute of Genetics and of Molecular and Cellular Biology (IGBMC), Illkirch, France
- Université de Strasbourg, Illkirch, France
- Institut National de la Santé et de la Recherche Médicale (INSERM), Illkirch, France
- Centre National de la Recherche Scientifique (CNRS) UMR 7104, Illkirch, France
| | - Isabelle M L Billas
- Centre for Integrative Biology (CBI), Department of Integrated Structural Biology, Institute of Genetics and of Molecular and Cellular Biology (IGBMC), Illkirch, France
- Université de Strasbourg, Illkirch, France
- Institut National de la Santé et de la Recherche Médicale (INSERM), Illkirch, France
- Centre National de la Recherche Scientifique (CNRS) UMR 7104, Illkirch, France
| | - Karl Edman
- Mechanistic & Structural Biology, Discovery Sciences, R&D, AstraZeneca, Gothenburg, Sweden.
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13
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Butz H, Saskői É, Krokker L, Vereczki V, Alpár A, Likó I, Tóth E, Szőcs E, Cserepes M, Nagy K, Kacskovics I, Patócs A. Context-Dependent Role of Glucocorticoid Receptor Alpha and Beta in Breast Cancer Cell Behaviour. Cells 2023; 12:cells12050784. [PMID: 36899920 PMCID: PMC10000936 DOI: 10.3390/cells12050784] [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: 01/05/2023] [Revised: 02/22/2023] [Accepted: 02/24/2023] [Indexed: 03/06/2023] Open
Abstract
Background. The dual role of GCs has been observed in breast cancer; however, due to many concomitant factors, GR action in cancer biology is still ambiguous. In this study, we aimed to unravel the context-dependent action of GR in breast cancer. Methods. GR expression was characterized in multiple cohorts: (1) 24,256 breast cancer specimens on the RNA level, 220 samples on the protein level and correlated with clinicopathological data; (2) oestrogen receptor (ER)-positive and -negative cell lines were used to test for the presence of ER and ligand, and the effect of the GRβ isoform following GRα and GRβ overexpression on GR action, by in vitro functional assays. Results. We found that GR expression was higher in ER- breast cancer cells compared to ER+ ones, and GR-transactivated genes were implicated mainly in cell migration. Immunohistochemistry showed mostly cytoplasmic but heterogenous staining irrespective of ER status. GRα increased cell proliferation, viability, and the migration of ER- cells. GRβ had a similar effect on breast cancer cell viability, proliferation, and migration. However, the GRβ isoform had the opposite effect depending on the presence of ER: an increased dead cell ratio was found in ER+ breast cancer cells compared to ER- ones. Interestingly, GRα and GRβ action did not depend on the presence of the ligand, suggesting the role of the "intrinsic", ligand-independent action of GR in breast cancer. Conclusions. Staining differences using different GR antibodies may be the reason behind controversial findings in the literature regarding the expression of GR protein and clinicopathological data. Therefore, caution in the interpretation of immunohistochemistry should be applied. By dissecting the effects of GRα and GRβ, we found that the presence of the GR in the context of ER had a different effect on cancer cell behaviour, but independently of ligand availability. Additionally, GR-transactivated genes are mostly involved in cell migration, which raises GR's importance in disease progression.
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Affiliation(s)
- Henriett Butz
- Department of Molecular Genetics and the National Tumour Biology Laboratory, National Institute of Oncology, H-1122 Budapest, Hungary
- Department of Oncology Biobank, National Institute of Oncology, H-1122 Budapest, Hungary
- Hereditary Tumours Research Group, Hungarian Academy of Sciences, Semmelweis University, H-1089 Budapest, Hungary
- Department of Laboratory Medicine, Semmelweis University, H-1089 Budapest, Hungary
- Correspondence:
| | - Éva Saskői
- Department of Oncology Biobank, National Institute of Oncology, H-1122 Budapest, Hungary
| | - Lilla Krokker
- Hereditary Tumours Research Group, Hungarian Academy of Sciences, Semmelweis University, H-1089 Budapest, Hungary
- Department of Laboratory Medicine, Semmelweis University, H-1089 Budapest, Hungary
| | - Viktória Vereczki
- Department of Molecular Genetics and the National Tumour Biology Laboratory, National Institute of Oncology, H-1122 Budapest, Hungary
| | - Alán Alpár
- Department of Anatomy, Semmelweis University, H-1094 Budapest, Hungary
| | - István Likó
- Hereditary Tumours Research Group, Hungarian Academy of Sciences, Semmelweis University, H-1089 Budapest, Hungary
| | - Erika Tóth
- Department of Pathology, National Institute of Oncology, H-1122 Budapest, Hungary
| | - Erika Szőcs
- Department of Oncology Biobank, National Institute of Oncology, H-1122 Budapest, Hungary
| | - Mihály Cserepes
- Department of Experimental Pharmacology, National Institute of Oncology, H-1122 Budapest, Hungary
| | | | | | - Attila Patócs
- Department of Molecular Genetics and the National Tumour Biology Laboratory, National Institute of Oncology, H-1122 Budapest, Hungary
- Department of Oncology Biobank, National Institute of Oncology, H-1122 Budapest, Hungary
- Hereditary Tumours Research Group, Hungarian Academy of Sciences, Semmelweis University, H-1089 Budapest, Hungary
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14
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Wang Y, Gao J, Yu Y, Zhou L, Wang M, Xue W, Liu B, Wu X, Wu X, Gao H, Shen Y, Xu Q. A plant-derived glucocorticoid receptor modulator with potency to attenuate the side effects of glucocorticoid therapy. Br J Pharmacol 2023; 180:194-213. [PMID: 36165414 DOI: 10.1111/bph.15957] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 08/19/2022] [Accepted: 09/17/2022] [Indexed: 12/01/2022] Open
Abstract
BACKGROUND AND PURPOSE Continuous efforts have been made to move towards maintaining the beneficial anti-inflammatory functions of glucocorticoids (GCs) while minimizing side effects. Here, we investigated the selective glucocorticoid receptor (GR) modulator-like properties of a plant-derived compound caesaldekarin e (CA-e). EXPERIMENTAL APPROACH The therapeutic efficacy of CA-e was evaluated in several mouse models, including dextran sulfate sodium-induced colitis, ovalbumin-induced lung allergic inflammation, imiquimod-induced psoriasis-like skin inflammation and skin atrophy. The action of CA-e targeting the GR was analysed using molecular docking, cellular thermal shift assays and microscale thermophoresis. Other methods included DNA-protein pull-down assays and mass spectrometry. KEY RESULTS CA-e selectively inhibited positive GC response element ((+) GRE)-mediated direct transactivation while maintaining and even enhancing the anti-inflammatory effects of treatment with dexamethasone. CA-e, alone and in combination with dexamethasone, efficiently alleviated inflammation in several mouse models with milder side effects compared with dexamethasone alone. Mechanistically, CA-e inhibited the formation of dimers by binding to the dimerization interface located in the ligand-binding domain of GR and facilitated embryonic ectoderm development that is involved in the regulation of transcriptional repression to compete for binding to (+) GRE, eventually leading to the repression of (+) GRE-regulated genes. In addition, CA-e repressed NF-κB-dependent genes by enhancing the interaction between GR and p65. CONCLUSIONS AND IMPLICATIONS Our results reveal that CA-e is a novel GR modulator with strong potency to attenuate the side effects of GC therapy and can be used as a potential molecular tool for deciphering GR signalling.
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Affiliation(s)
- Yixuan Wang
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, China
| | - Jian Gao
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, China
| | - Ying Yu
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, China
| | - Lin Zhou
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, China
| | - Miao Wang
- School of Traditional Chinese Materia Medica, Shenyang Pharmaceutical University, Shenyang, China
| | - Wenwen Xue
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, China
| | - Bo Liu
- State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, Sichuan University, Collaborative Innovation Center of Biotherapy, Chengdu, China
| | - Xudong Wu
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, China
| | - Xuefeng Wu
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, China
| | - Huiyuan Gao
- School of Traditional Chinese Materia Medica, Shenyang Pharmaceutical University, Shenyang, China
| | - Yan Shen
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, China
| | - Qiang Xu
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, China
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15
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Jeon DY, Jeong SY, Lee JW, Kim J, Kim JH, Chu HS, Jeong WJ, Lee BJ, Ahn B, Kim J, Choi SH, Park JW. FOXO1 Is a Key Mediator of Glucocorticoid-Induced Expression of Tristetraprolin in MDA-MB-231 Breast Cancer Cells. Int J Mol Sci 2022; 23:ijms232213673. [PMID: 36430156 PMCID: PMC9693238 DOI: 10.3390/ijms232213673] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Revised: 11/03/2022] [Accepted: 11/04/2022] [Indexed: 11/10/2022] Open
Abstract
The mRNA destabilizing factor tristetraprolin (TTP) functions as a tumor suppressor by down-regulating cancer-associated genes. TTP expression is significantly reduced in various cancers, which contributes to cancer processes. Enforced expression of TTP impairs tumorigenesis and abolishes maintenance of the malignant state, emphasizing the need to identify a TTP inducer in cancer cells. To search for novel candidate agents for inducing TTP in cancer cells, we screened a library containing 1019 natural compounds using MCF-7 breast cancer cells transfected with a reporter vector containing the TTP promoter upstream of the luciferase gene. We identified one molecule, of which the enantiomers are betamethasone 21-phosphate (BTM-21-P) and dexamethasone 21-phosphate (BTM-21-P), as a potent inducer of TTP in cancer cells. We confirmed that BTM-21-P, DXM-21-P, and dexamethasone (DXM) induced the expression of TTP in MDA-MB-231 cells in a glucocorticoid receptor (GR)-dependent manner. To identify potential pathways linking BTM-21-P and DXM-21-P to TTP induction, we performed an RNA sequencing-based transcriptome analysis of MDA-MB-231 cells at 3 h after treatment with these compounds. A heat map analysis of FPKM expression showed a similar expression pattern between cells treated with the two compounds. The KEGG pathway analysis results revealed that the upregulated DEGs were strongly associated with several pathways, including the Hippo signaling pathway, PI3K-Akt signaling pathway, FOXO signaling pathway, NF-κB signaling pathway, and p53 signaling pathway. Inhibition of the FOXO pathway using a FOXO1 inhibitor blocked the effects of BTM-21-P and DXM-21-P on the induction of TTP in MDA-MB-231 cells. We found that DXM enhanced the binding of FOXO1 to the TTP promoter in a GR-dependent manner. In conclusion, we identified a natural compound of which the enantiomers are DXM-21-P and BTM-21-P as a potent inducer of TTP in breast cancer cells. We also present new insights into the role of FOXO1 in the DXM-21-P- and BTM-21-P-induced expression of TTP in cancer cells.
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Affiliation(s)
- Do Yong Jeon
- Department of Biological Sciences, University of Ulsan, Ulsan 44610, Korea
| | - So Yeon Jeong
- Department of Biological Sciences, University of Ulsan, Ulsan 44610, Korea
| | - Ju Won Lee
- Department of Biological Sciences, University of Ulsan, Ulsan 44610, Korea
| | - Jeonghwan Kim
- School of System Biomedical Science, Soongsil University, Seoul 06978, Korea
| | - Jee Hyun Kim
- RopheLBio, B102, Seoul Forest M Tower, Seoul 04778, Korea
| | - Hun Su Chu
- RopheLBio, B102, Seoul Forest M Tower, Seoul 04778, Korea
| | - Won Jin Jeong
- RopheLBio, B102, Seoul Forest M Tower, Seoul 04778, Korea
| | - Byung Ju Lee
- Department of Biological Sciences, University of Ulsan, Ulsan 44610, Korea
| | - Byungyong Ahn
- Department of Food Science and Nutrition, University of Ulsan, Ulsan 44610, Korea
| | - Junil Kim
- School of System Biomedical Science, Soongsil University, Seoul 06978, Korea
| | - Seong Hee Choi
- RopheLBio, B102, Seoul Forest M Tower, Seoul 04778, Korea
- Correspondence: (S.H.C.); (J.W.P.)
| | - Jeong Woo Park
- Department of Biological Sciences, University of Ulsan, Ulsan 44610, Korea
- Correspondence: (S.H.C.); (J.W.P.)
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16
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Henning P, Conaway HH, Lerner UH. Stimulation of osteoclast formation and bone resorption by glucocorticoids: Synergistic interactions with the calcium regulating hormones parathyroid hormone and 1,25(OH) 2-vitamin D3. VITAMINS AND HORMONES 2022; 120:231-270. [PMID: 35953112 DOI: 10.1016/bs.vh.2022.04.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Osteoporosis is a significant health problem, with skeletal fractures increasing morbidity and mortality. Excess glucocorticoids (GC) represents the leading cause of secondary osteoporosis. The first phase of glucocorticoid-induced osteoporosis is increased bone resorption. In this Chapter, in vitro studies of the direct glucocorticoid receptor (GR) mediated cellular effects of GC on osteoclasts to affect bone resorption and indirect effects on osteoblast lineage cells to increase the RANKL/OPG ratio and stimulate osteoclastogenesis and bone resorption are reviewed in detail, together with detailed descriptions of in vivo effects of GC in different portions of the skeleton in research animals and humans. Brief sections are devoted to contrasting functions of GC in osteonecrosis, vitamin D formation, in vitro and in vivo bone resorptive actions dependent on vitamin D receptor and vitamin D toxicity, as well as the molecular basis of GR action. Included are also more detailed assessments of the interactions of GC with the major calcium regulating hormones, 1,25(OH)2-vitamin D3 and parathyroid hormone, describing the in vitro increases in RANKL/OPG ratios, osteoclastogenesis and synergistic bone resorption that occurs when GC is combined with either 1,25(OH)2-vitamin D3 or parathyroid hormone. Additionally, a molecular basic for the synergistic interaction of GC with 1,25(OH)2-vitamin D3 is provided along with a suggested molecular basic for the interaction between GC and parathyroid hormone.
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Affiliation(s)
- Petra Henning
- Department of Internal Medicine and Clinical Nutrition, Institute of Medicine, Sahlgrenska Osteoporosis Centre and Centre for Bone and Arthritis Research at the Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - H Herschel Conaway
- Department of Physiology and Cell Biology, University of Arkansas for Medical Sciences, Little Rock, Arkansas, United States
| | - Ulf H Lerner
- Department of Internal Medicine and Clinical Nutrition, Institute of Medicine, Sahlgrenska Osteoporosis Centre and Centre for Bone and Arthritis Research at the Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
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17
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Dinarello A, Tesoriere A, Martini P, Fontana CM, Volpato D, Badenetti L, Terrin F, Facchinello N, Romualdi C, Carnevali O, Dalla Valle L, Argenton F. Zebrafish Mutant Lines Reveal the Interplay between nr3c1 and nr3c2 in the GC-Dependent Regulation of Gene Transcription. Int J Mol Sci 2022; 23:ijms23052678. [PMID: 35269817 PMCID: PMC8910431 DOI: 10.3390/ijms23052678] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 02/24/2022] [Accepted: 02/24/2022] [Indexed: 02/04/2023] Open
Abstract
Glucocorticoids mainly exert their biological functions through their cognate receptor, encoded by the nr3c1 gene. Here, we analysed the glucocorticoids mechanism of action taking advantage of the availability of different zebrafish mutant lines for their receptor. The differences in gene expression patterns between the zebrafish gr knock-out and the grs357 mutant line, in which a point mutation prevents binding of the receptor to the hormone-responsive elements, reveal an intricate network of GC-dependent transcription. Particularly, we show that Stat3 transcriptional activity mainly relies on glucocorticoid receptor GR tethering activity: several Stat3 target genes are induced upon glucocorticoid GC exposure both in wild type and in grs357/s357 larvae, but not in gr knock-out zebrafish. To understand the interplay between GC, their receptor, and the mineralocorticoid receptor, which is evolutionarily and structurally related to the GR, we generated an mr knock-out line and observed that several GC-target genes also need a functional mineralocorticoid receptor MR to be correctly transcribed. All in all, zebrafish mutants and transgenic models allow in vivo analysis of GR transcriptional activities and interactions with other transcription factors such as MR and Stat3 in an in-depth and rapid way.
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Affiliation(s)
- Alberto Dinarello
- Department of Biology, University of Padova, 35121 Padova, Italy; (A.D.); (A.T.); (C.M.F.); (D.V.); (L.B.); (F.T.); (N.F.); (C.R.); (F.A.)
| | - Annachiara Tesoriere
- Department of Biology, University of Padova, 35121 Padova, Italy; (A.D.); (A.T.); (C.M.F.); (D.V.); (L.B.); (F.T.); (N.F.); (C.R.); (F.A.)
| | - Paolo Martini
- Department of Molecular and Translational Medicine, University of Brescia, 25121 Brescia, Italy;
| | - Camilla Maria Fontana
- Department of Biology, University of Padova, 35121 Padova, Italy; (A.D.); (A.T.); (C.M.F.); (D.V.); (L.B.); (F.T.); (N.F.); (C.R.); (F.A.)
| | - Davide Volpato
- Department of Biology, University of Padova, 35121 Padova, Italy; (A.D.); (A.T.); (C.M.F.); (D.V.); (L.B.); (F.T.); (N.F.); (C.R.); (F.A.)
| | - Lorenzo Badenetti
- Department of Biology, University of Padova, 35121 Padova, Italy; (A.D.); (A.T.); (C.M.F.); (D.V.); (L.B.); (F.T.); (N.F.); (C.R.); (F.A.)
| | - Francesca Terrin
- Department of Biology, University of Padova, 35121 Padova, Italy; (A.D.); (A.T.); (C.M.F.); (D.V.); (L.B.); (F.T.); (N.F.); (C.R.); (F.A.)
| | - Nicola Facchinello
- Department of Biology, University of Padova, 35121 Padova, Italy; (A.D.); (A.T.); (C.M.F.); (D.V.); (L.B.); (F.T.); (N.F.); (C.R.); (F.A.)
| | - Chiara Romualdi
- Department of Biology, University of Padova, 35121 Padova, Italy; (A.D.); (A.T.); (C.M.F.); (D.V.); (L.B.); (F.T.); (N.F.); (C.R.); (F.A.)
| | - Oliana Carnevali
- Department of Life and Environmental Sciences, Università Politecnica delle Marche, 60131 Ancona, Italy;
| | - Luisa Dalla Valle
- Department of Biology, University of Padova, 35121 Padova, Italy; (A.D.); (A.T.); (C.M.F.); (D.V.); (L.B.); (F.T.); (N.F.); (C.R.); (F.A.)
- Correspondence:
| | - Francesco Argenton
- Department of Biology, University of Padova, 35121 Padova, Italy; (A.D.); (A.T.); (C.M.F.); (D.V.); (L.B.); (F.T.); (N.F.); (C.R.); (F.A.)
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18
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Datta RR, Rister J. The power of the (imperfect) palindrome: Sequence-specific roles of palindromic motifs in gene regulation. Bioessays 2022; 44:e2100191. [PMID: 35195290 PMCID: PMC8957550 DOI: 10.1002/bies.202100191] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Revised: 02/01/2022] [Accepted: 02/03/2022] [Indexed: 12/22/2022]
Abstract
In human languages, a palindrome reads the same forward as backward (e.g., 'madam'). In regulatory DNA, a palindrome is an inverted sequence repeat that allows a transcription factor to bind as a homodimer or as a heterodimer with another type of transcription factor. Regulatory palindromes are typically imperfect, that is, the repeated sequences differ in at least one base pair, but the functional significance of this asymmetry remains poorly understood. Here, we review the use of imperfect palindromes in Drosophila photoreceptor differentiation and mammalian steroid receptor signaling. Moreover, we discuss mechanistic explanations for the predominance of imperfect palindromes over perfect palindromes in these two gene regulatory contexts. Lastly, we propose to elucidate whether specific imperfectly palindromic variants have specific regulatory functions in steroid receptor signaling and whether such variants can help predict transcriptional outcomes as well as the response of individual patients to drug treatments.
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Affiliation(s)
- Rhea R Datta
- Department of Biology, Hamilton College, Clinton, New York, USA
| | - Jens Rister
- Department of Biology, University of Massachusetts Boston, Integrated Sciences Complex, Boston, Massachusetts, USA
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19
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Timmermans S, Vandewalle J, Libert C. Dimerization of the Glucocorticoid Receptor and Its Importance in (Patho)physiology: A Primer. Cells 2022; 11:cells11040683. [PMID: 35203332 PMCID: PMC8870481 DOI: 10.3390/cells11040683] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 02/10/2022] [Accepted: 02/13/2022] [Indexed: 02/01/2023] Open
Abstract
The glucocorticoid receptor (GR) is a very versatile protein that comes in several forms, interacts with many proteins and has multiple functions. Numerous therapies are based on GRs’ actions but the occurrence of side effects and reduced responses to glucocorticoids have motivated scientists to study GRs in great detail. The notion that GRs can perform functions as a monomeric protein, but also as a homodimer has raised questions about the underlying mechanisms, structural aspects of dimerization, influencing factors and biological functions. In this review paper, we are providing an overview of the current knowledge and insights about this important aspect of GR biology.
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Affiliation(s)
- Steven Timmermans
- Center for Inflammation Research, VIB, 9052 Ghent, Belgium; (S.T.); (J.V.)
- Department of Biomedical Molecular Biology, Ghent University, 9052 Ghent, Belgium
| | - Jolien Vandewalle
- Center for Inflammation Research, VIB, 9052 Ghent, Belgium; (S.T.); (J.V.)
- Department of Biomedical Molecular Biology, Ghent University, 9052 Ghent, Belgium
| | - Claude Libert
- Center for Inflammation Research, VIB, 9052 Ghent, Belgium; (S.T.); (J.V.)
- Department of Biomedical Molecular Biology, Ghent University, 9052 Ghent, Belgium
- Correspondence:
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20
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Timmermans S, Verhoog NJD, Van Looveren K, Dewaele S, Hochepied T, Eggermont M, Gilbert B, Boerema-de Munck A, Vanderhaeghen T, Vanden Berghe J, Garcia Gonzalez N, Vandewalle J, Bloch Y, Provost M, Savvides SN, De Bosscher K, Declercq W, Rottier RJ, Louw A, Libert C. Point mutation I634A in the glucocorticoid receptor causes embryonic lethality by reduced ligand binding. J Biol Chem 2022; 298:101574. [PMID: 35007536 PMCID: PMC8808175 DOI: 10.1016/j.jbc.2022.101574] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Revised: 12/30/2021] [Accepted: 12/31/2021] [Indexed: 12/23/2022] Open
Abstract
The glucocorticoid (GC) receptor (GR) is essential for normal development and in the initiation of inflammation. Healthy GRdim/dim mice with reduced dimerization propensity due to a point mutation (A465T) at the dimer interface of the GR DNA-binding domain (DBD) (here GRD/D) have previously helped to define the functions of GR monomers and dimers. Since GRD/D retains residual dimerization capacity, here we generated the dimer-nullifying double mutant GRD+L/D+L mice, featuring an additional mutation (I634A) in the ligand-binding domain (LBD) of GR. These mice are perinatally lethal, as are GRL/L mice (these mice have the I634A mutation but not the A465T mutation), displaying improper lung and skin formation. Using embryonic fibroblasts, high and low doses of dexamethasone (Dex), nuclear translocation assays, RNAseq, dimerization assays, and ligand-binding assays (and Kd values), we found that the lethal phenotype in these mice is due to insufficient ligand binding. These data suggest there is some correlation between GR dimerization potential and ligand affinity. We conclude that even a mutation as subtle as I634A, at a position not directly involved in ligand interactions sensu stricto, can still influence ligand binding and have a lethal outcome.
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Affiliation(s)
- Steven Timmermans
- VIB Center for Inflammation Research, VIB, Ghent, Belgium; Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
| | | | - Kelly Van Looveren
- VIB Center for Inflammation Research, VIB, Ghent, Belgium; Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
| | - Sylviane Dewaele
- VIB Center for Inflammation Research, VIB, Ghent, Belgium; Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
| | - Tino Hochepied
- VIB Center for Inflammation Research, VIB, Ghent, Belgium; Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
| | - Melanie Eggermont
- VIB Center for Inflammation Research, VIB, Ghent, Belgium; Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
| | - Barbara Gilbert
- VIB Center for Inflammation Research, VIB, Ghent, Belgium; Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
| | - Anne Boerema-de Munck
- Department of Pediatric Surgery, Erasmus Medical Center, Sophia Children's Hospital, Rotterdam, The Netherlands; Department of Cell Biology, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Tineke Vanderhaeghen
- VIB Center for Inflammation Research, VIB, Ghent, Belgium; Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
| | - Joke Vanden Berghe
- VIB Center for Inflammation Research, VIB, Ghent, Belgium; Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
| | - Natalia Garcia Gonzalez
- VIB Center for Inflammation Research, VIB, Ghent, Belgium; Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
| | - Jolien Vandewalle
- VIB Center for Inflammation Research, VIB, Ghent, Belgium; Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
| | - Yehudi Bloch
- VIB Center for Inflammation Research, VIB, Ghent, Belgium; Department of Biochemistry and Microbiology, Ghent University, Ghent, Belgium
| | - Mathias Provost
- VIB Center for Inflammation Research, VIB, Ghent, Belgium; Department of Biochemistry and Microbiology, Ghent University, Ghent, Belgium
| | - Savvas N Savvides
- VIB Center for Inflammation Research, VIB, Ghent, Belgium; Department of Biochemistry and Microbiology, Ghent University, Ghent, Belgium
| | - Karolien De Bosscher
- Department of Biochemistry, Ghent University, Ghent, Belgium; Receptor Research Laboratories, Nuclear Receptor Lab, Medical Biotechnology Center, VIB, Ghent, Belgium
| | - Wim Declercq
- VIB Center for Inflammation Research, VIB, Ghent, Belgium; Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
| | - Robbert J Rottier
- Department of Pediatric Surgery, Erasmus Medical Center, Sophia Children's Hospital, Rotterdam, The Netherlands; Department of Cell Biology, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Ann Louw
- Department of Biochemistry, Stellenbosch University, Stellenbosch, South Africa
| | - Claude Libert
- VIB Center for Inflammation Research, VIB, Ghent, Belgium; Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium.
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21
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Butz H, Patócs A. Mechanisms behind context-dependent role of glucocorticoids in breast cancer progression. Cancer Metastasis Rev 2022; 41:803-832. [PMID: 35761157 PMCID: PMC9758252 DOI: 10.1007/s10555-022-10047-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Accepted: 06/09/2022] [Indexed: 02/08/2023]
Abstract
Glucocorticoids (GCs), mostly dexamethasone (dex), are routinely administered as adjuvant therapy to manage side effects in breast cancer. However, recently, it has been revealed that dex triggers different effects and correlates with opposite outcomes depending on the breast cancer molecular subtype. This has raised new concerns regarding the generalized use of GC and suggested that the context-dependent effects of GCs can be taken into potential consideration during treatment design. Based on this, attention has recently been drawn to the role of the glucocorticoid receptor (GR) in development and progression of breast cancer. Therefore, in this comprehensive review, we aimed to summarize the different mechanisms behind different context-dependent GC actions in breast cancer by applying a multilevel examination, starting from the association of variants of the GR-encoding gene to expression at the mRNA and protein level of the receptor, and its interactions with other factors influencing GC action in breast cancer. The role of GCs in chemosensitivity and chemoresistance observed during breast cancer therapy is discussed. In addition, experiences using GC targeting therapeutic options (already used and investigated in preclinical and clinical trials), such as classic GC dexamethasone, selective glucocorticoid receptor agonists and modulators, the GC antagonist mifepristone, and GR coregulators, are also summarized. Evidence presented can aid a better understanding of the biology of context-dependent GC action that can lead to further advances in the personalized therapy of breast cancer by the evaluation of GR along with the conventional estrogen receptor (ER) and progesterone receptor (PR) in the routine diagnostic procedure.
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Affiliation(s)
- Henriett Butz
- Department of Molecular Genetics and the National Tumor Biology Laboratory, National Institute of Oncology, Budapest, Hungary.
- Hereditary Tumours Research Group, Hungarian Academy of Sciences-Semmelweis University, Budapest, Hungary.
- Department of Laboratory Medicine, Semmelweis University, Budapest, Hungary.
| | - Attila Patócs
- Department of Molecular Genetics and the National Tumor Biology Laboratory, National Institute of Oncology, Budapest, Hungary
- Hereditary Tumours Research Group, Hungarian Academy of Sciences-Semmelweis University, Budapest, Hungary
- Department of Laboratory Medicine, Semmelweis University, Budapest, Hungary
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22
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Reichardt SD, Amouret A, Muzzi C, Vettorazzi S, Tuckermann JP, Lühder F, Reichardt HM. The Role of Glucocorticoids in Inflammatory Diseases. Cells 2021; 10:cells10112921. [PMID: 34831143 PMCID: PMC8616489 DOI: 10.3390/cells10112921] [Citation(s) in RCA: 43] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 10/19/2021] [Accepted: 10/26/2021] [Indexed: 02/07/2023] Open
Abstract
For more than 70 years, glucocorticoids (GCs) have been a powerful and affordable treatment option for inflammatory diseases. However, their benefits do not come without a cost, since GCs also cause side effects. Therefore, strong efforts are being made to improve their therapeutic index. In this review, we illustrate the mechanisms and target cells of GCs in the pathogenesis and treatment of some of the most frequent inflammatory disorders affecting the central nervous system, the gastrointestinal tract, the lung, and the joints, as well as graft-versus-host disease, which often develops after hematopoietic stem cell transplantation. In addition, an overview is provided of novel approaches aimed at improving GC therapy based on chemical modifications or GC delivery using nanoformulations. GCs remain a topic of highly active scientific research despite being one of the oldest class of drugs in medical use.
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Affiliation(s)
- Sybille D. Reichardt
- Institute for Cellular and Molecular Immunology, University Medical Center Göttingen, 37073 Göttingen, Germany; (S.D.R.); (A.A.); (C.M.)
| | - Agathe Amouret
- Institute for Cellular and Molecular Immunology, University Medical Center Göttingen, 37073 Göttingen, Germany; (S.D.R.); (A.A.); (C.M.)
| | - Chiara Muzzi
- Institute for Cellular and Molecular Immunology, University Medical Center Göttingen, 37073 Göttingen, Germany; (S.D.R.); (A.A.); (C.M.)
| | - Sabine Vettorazzi
- Institute of Comparative Molecular Endocrinology, Ulm University, 89081 Ulm, Germany; (S.V.); (J.P.T.)
| | - Jan P. Tuckermann
- Institute of Comparative Molecular Endocrinology, Ulm University, 89081 Ulm, Germany; (S.V.); (J.P.T.)
| | - Fred Lühder
- Institute for Neuroimmunology and Multiple Sclerosis Research, University Medical Center Göttingen, 37075 Göttingen, Germany;
| | - Holger M. Reichardt
- Institute for Cellular and Molecular Immunology, University Medical Center Göttingen, 37073 Göttingen, Germany; (S.D.R.); (A.A.); (C.M.)
- Correspondence: ; Tel.: +49-551-3963365
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23
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Shimba A, Ejima A, Ikuta K. Pleiotropic Effects of Glucocorticoids on the Immune System in Circadian Rhythm and Stress. Front Immunol 2021; 12:706951. [PMID: 34691020 PMCID: PMC8531522 DOI: 10.3389/fimmu.2021.706951] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2021] [Accepted: 09/22/2021] [Indexed: 12/16/2022] Open
Abstract
Glucocorticoids (GCs) are a class of steroid hormones secreted from the adrenal cortex. Their production is controlled by circadian rhythm and stress, the latter of which includes physical restraint, hunger, and inflammation. Importantly, GCs have various effects on immunity, metabolism, and cognition, including pleiotropic effects on the immune system. In general, GCs have strong anti-inflammatory and immunosuppressive effects. Indeed, they suppress inflammatory cytokine expression and cell-mediated immunity, leading to increased risks of some infections. However, recent studies have shown that endogenous GCs induced by the diurnal cycle and dietary restriction enhance immune responses against some infections by promoting the survival, redistribution, and response of T and B cells via cytokine and chemokine receptors. Furthermore, although GCs are reported to reduce expression of Th2 cytokines, GCs enhance type 2 immunity and IL-17-associated immunity in some stress conditions. Taken together, GCs have both immunoenhancing and immunosuppressive effects on the immune system.
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Affiliation(s)
- Akihiro Shimba
- Laboratory of Immune Regulation, Department of Virus Research, Institute for Frontier Life and Medical Sciences, Kyoto University, Kyoto, Japan.,Department of Human Health Sciences, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Aki Ejima
- Laboratory of Immune Regulation, Department of Virus Research, Institute for Frontier Life and Medical Sciences, Kyoto University, Kyoto, Japan.,Graduate School of Biostudies, Kyoto University, Kyoto, Japan
| | - Koichi Ikuta
- Laboratory of Immune Regulation, Department of Virus Research, Institute for Frontier Life and Medical Sciences, Kyoto University, Kyoto, Japan
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24
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Bothe M, Buschow R, Meijsing SH. Glucocorticoid signaling induces transcriptional memory and universally reversible chromatin changes. Life Sci Alliance 2021; 4:4/10/e202101080. [PMID: 34446533 PMCID: PMC8403771 DOI: 10.26508/lsa.202101080] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 08/12/2021] [Accepted: 08/12/2021] [Indexed: 01/22/2023] Open
Abstract
Glucocorticoids are stress hormones that elicit various cellular responses. These responses are typically reversible; however, in some instances, a previous exposure is “remembered” and influences the response to a subsequent hormone encounter. Glucocorticoids are stress hormones that elicit cellular responses by binding to the glucocorticoid receptor, a ligand-activated transcription factor. The exposure of cells to this hormone induces wide-spread changes in the chromatin landscape and gene expression. Previous studies have suggested that some of these changes are reversible whereas others persist even when the hormone is no longer around. However, when we examined chromatin accessibility in human airway epithelial cells after hormone washout, we found that the hormone-induced changes were universally reversed after 1 d. Moreover, priming of cells by a previous exposure to hormone, in general, did not alter the transcriptional response to a subsequent encounter of the same cue except for one gene, ZBTB16, that displays transcriptional memory manifesting itself as a more robust transcriptional response upon repeated hormone stimulation. Single-cell analysis revealed that the more robust response is driven by a higher probability of primed cells to activate ZBTB16 and by a subset of cells that express the gene at levels that are higher than the induction levels observed for naïve cells.
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Affiliation(s)
- Melissa Bothe
- Max Planck Institute for Molecular Genetics, Berlin, Germany
| | - René Buschow
- Max Planck Institute for Molecular Genetics, Berlin, Germany
| | - Sebastiaan H Meijsing
- Max Planck Institute for Molecular Genetics, Berlin, Germany .,Max Planck Unit for the Science of Pathogens, Berlin, Germany
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25
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Frank F, Liu X, Ortlund EA. Glucocorticoid receptor condensates link DNA-dependent receptor dimerization and transcriptional transactivation. Proc Natl Acad Sci U S A 2021; 118:e2024685118. [PMID: 34285072 PMCID: PMC8325269 DOI: 10.1073/pnas.2024685118] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The glucocorticoid receptor (GR) is a ligand-regulated transcription factor (TF) that controls the tissue- and gene-specific transactivation and transrepression of thousands of target genes. Distinct GR DNA-binding sequences with activating or repressive activities have been identified, but how they modulate transcription in opposite ways is not known. We show that GR forms phase-separated condensates that specifically concentrate known coregulators via their intrinsically disordered regions (IDRs) in vitro. A combination of dynamic, multivalent (between IDRs) and specific, stable interactions (between LxxLL motifs and the GR ligand-binding domain) control the degree of recruitment. Importantly, GR DNA binding directs the selective partitioning of coregulators within GR condensates such that activating DNAs cause enhanced recruitment of coactivators. Our work shows that condensation controls GR function by modulating coregulator recruitment and provides a mechanism for the up- and down-regulation of GR target genes controlled by distinct DNA recognition elements.
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Affiliation(s)
- Filipp Frank
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA 30322
| | - Xu Liu
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA 30322
| | - Eric A Ortlund
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA 30322
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26
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Regulation of neurotropic herpesvirus productive infection and latency-reactivation cycle by glucocorticoid receptor and stress-induced transcription factors. VITAMINS AND HORMONES 2021; 117:101-132. [PMID: 34420577 DOI: 10.1016/bs.vh.2021.06.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Neurotropic α-herpesvirinae subfamily members, herpes simplex virus type 1 (HSV-1) and bovine herpesvirus 1 (BoHV-1), are important viral pathogens in their respective hosts. Following acute infection on mucosal surfaces, these viruses establish life-long latency in neurons within trigeminal ganglia (TG) and central nervous system. Chronic or acute stress (physiological or psychological) increases the frequency of reactivation from latency, which leads to virus shedding, virus transmission, and recurrent disease. While stress impairs immune responses and inflammatory signaling cascades, we predict stressful stimuli directly stimulate viral gene expression and productive infection during early stages of reactivation from latency. For example, BoHV-1 and HSV-1 productive infection is impaired by glucocorticoid receptor (GR) antagonists but is stimulated by the synthetic corticosteroid dexamethasone. Promoters that drive expression of key viral transcriptional regulatory proteins are cooperatively stimulated by GR and specific Krüppel like transcription factors (KLF) induced during stress induced reactivation from latency. The BoHV-1 immediate early transcription unit 1 promoter and contains two GR response elements (GRE) that are essential for cooperative transactivation by GR and KLF15. Conversely, the HSV-1 infected cell protein 0 (ICP0) and ICP4 promoter as well as the BoHV-1 ICP0 early promoter lack consensus GREs: however, these promoters are cooperatively transactivated by GR and KLF4 or KLF15. Hence, growing evidence suggests GR and stress-induced transcription factors directly stimulate viral gene expression and productive infection during early stages of reactivation from latency. We predict the immune inhibitory effects of stress enhance virus spread at late stages during reactivation from latency.
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27
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Vettorazzi S, Nalbantoglu D, Gebhardt JCM, Tuckermann J. A guide to changing paradigms of glucocorticoid receptor function-a model system for genome regulation and physiology. FEBS J 2021; 289:5718-5743. [PMID: 34213830 DOI: 10.1111/febs.16100] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Revised: 06/08/2021] [Accepted: 07/01/2021] [Indexed: 12/13/2022]
Abstract
The glucocorticoid receptor (GR) is a bona fide ligand-regulated transcription factor. Cloned in the 80s, the GR has become one of the best-studied and clinically most relevant members of the nuclear receptor superfamily. Cooperative activity of GR with other transcription factors and a plethora of coregulators contribute to the tissue- and context-specific response toward the endogenous and pharmacological glucocorticoids (GCs). Furthermore, nontranscriptional activities in the cytoplasm are emerging as an additional function of GR. Over the past 40 years, the concepts of GR mechanisms of action had been constantly changing. Different methodologies in the pregenomic and genomic era of molecular biological research and recent cutting-edge technology in single-cell and single-molecule analysis are steadily evolving the views, how the GR in particular and transcriptional regulation in general act in physiological and pathological processes. In addition to the development of technologies for GR analysis, the use of model organisms provides insights how the GR in vivo executes GC action in tissue homeostasis, inflammation, and energy metabolism. The model organisms, namely the mouse, but also rats, zebrafish, and recently fruit flies carrying mutations of the GR became a major driving force to analyze the molecular function of GR in disease models. This guide provides an overview of the exciting research and paradigm shifts in the GR field from past to present with a focus on GR transcription factor networks, GR DNA-binding and single-cell analysis, and model systems.
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Affiliation(s)
- Sabine Vettorazzi
- Institute of Comparative Molecular Endocrinology (CME), Ulm University, Germany
| | - Denis Nalbantoglu
- Institute of Comparative Molecular Endocrinology (CME), Ulm University, Germany
| | | | - Jan Tuckermann
- Institute of Comparative Molecular Endocrinology (CME), Ulm University, Germany
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28
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Diaz-Jimenez D, Kolb JP, Cidlowski JA. Glucocorticoids as Regulators of Macrophage-Mediated Tissue Homeostasis. Front Immunol 2021; 12:669891. [PMID: 34079551 PMCID: PMC8165320 DOI: 10.3389/fimmu.2021.669891] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Accepted: 05/05/2021] [Indexed: 02/06/2023] Open
Abstract
Our immune system has evolved as a complex network of cells and tissues tasked with maintaining host homeostasis. This is evident during the inflammatory responses elicited during a microbial infection or traumatic tissue damage. These responses seek to eliminate foreign material or restore tissue integrity. Even during periods without explicit disturbances, the immune system plays prominent roles in tissue homeostasis. Perhaps one of the most studied cells in this regard is the macrophage. Tissue-resident macrophages are a heterogenous group of sensory cells that respond to a variety of environmental cues and are essential for organ function. Endogenously produced glucocorticoid hormones connect external environmental stress signals with the function of many cell types, producing profound changes in immune cells, including macrophages. Here, we review the current literature which demonstrates specific effects of glucocorticoids in several organ systems. We propose that tissue-resident macrophages, through glucocorticoid signaling, may play an underappreciated role as regulators of organ homeostasis.
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Affiliation(s)
- David Diaz-Jimenez
- Molecular Endocrinology Group, Signal Transduction Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC, United States
| | - Joseph P Kolb
- Molecular Endocrinology Group, Signal Transduction Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC, United States
| | - John A Cidlowski
- Molecular Endocrinology Group, Signal Transduction Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC, United States
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29
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β-Ionone Attenuates Dexamethasone-Induced Suppression of Collagen and Hyaluronic Acid Synthesis in Human Dermal Fibroblasts. Biomolecules 2021; 11:biom11050619. [PMID: 33919331 PMCID: PMC8143342 DOI: 10.3390/biom11050619] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Revised: 03/02/2021] [Accepted: 04/19/2021] [Indexed: 12/17/2022] Open
Abstract
Stress is a major contributing factor of skin aging, which is clinically characterized by wrinkles, loss of elasticity, and dryness. In particular, glucocorticoids are generally considered key hormones for promoting stress-induced skin aging through binding to glucocorticoid receptors (GRs). In this work, we aimed to investigate whether β-ionone (a compound occurring in various foods such as carrots and almonds) attenuates dexamethasone-induced suppression of collagen and hyaluronic acid synthesis in human dermal fibroblasts, and to explore the mechanisms involved. We found that β-ionone promoted collagen production dose-dependently and increased mRNA expression levels, including collagen type I α 1 chain (COL1A1) and COL1A2 in dexamethasone-treated human dermal fibroblasts. It also raised hyaluronic acid synthase mRNA expression and hyaluronic acid levels. Notably, β-ionone inhibited cortisol binding to GR, subsequent dexamethasone-induced GR signaling, and the expression of several GR target genes. Our results reveal the strong potential of β-ionone for preventing stress-induced skin aging and suggest that its effects are related to the inhibition of GR signaling in human dermal fibroblasts.
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Repression of transcription by the glucocorticoid receptor: A parsimonious model for the genomics era. J Biol Chem 2021; 296:100687. [PMID: 33891947 PMCID: PMC8141881 DOI: 10.1016/j.jbc.2021.100687] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Revised: 04/16/2021] [Accepted: 04/19/2021] [Indexed: 12/15/2022] Open
Abstract
Glucocorticoids are potent anti-inflammatory drugs that are used to treat an extraordinary range of human disease, including COVID-19, underscoring the ongoing importance of understanding their molecular mechanisms. Early studies of GR signaling led to broad acceptance of models in which glucocorticoid receptor (GR) monomers tether repressively to inflammatory transcription factors, thus abrogating inflammatory gene expression. However, newer data challenge this core concept and present an exciting opportunity to reframe our understanding of GR signaling. Here, we present an alternate, two-part model for transcriptional repression by glucocorticoids. First, widespread GR-mediated induction of transcription results in rapid, primary repression of inflammatory gene transcription and associated enhancers through competition-based mechanisms. Second, a subset of GR-induced genes, including targets that are regulated in coordination with inflammatory transcription factors such as NF-κB, exerts secondary repressive effects on inflammatory gene expression. Within this framework, emerging data indicate that the gene set regulated through the cooperative convergence of GR and NF-κB signaling is central to the broad clinical effectiveness of glucocorticoids in terminating inflammation and promoting tissue repair.
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Kulik M, Bothe M, Kibar G, Fuchs A, Schöne S, Prekovic S, Mayayo-Peralta I, Chung HR, Zwart W, Helsen C, Claessens F, Meijsing SH. Androgen and glucocorticoid receptor direct distinct transcriptional programs by receptor-specific and shared DNA binding sites. Nucleic Acids Res 2021; 49:3856-3875. [PMID: 33751115 PMCID: PMC8053126 DOI: 10.1093/nar/gkab185] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Revised: 02/16/2021] [Accepted: 03/12/2021] [Indexed: 12/22/2022] Open
Abstract
The glucocorticoid (GR) and androgen (AR) receptors execute unique functions in vivo, yet have nearly identical DNA binding specificities. To identify mechanisms that facilitate functional diversification among these transcription factor paralogs, we studied them in an equivalent cellular context. Analysis of chromatin and sequence suggest that divergent binding, and corresponding gene regulation, are driven by different abilities of AR and GR to interact with relatively inaccessible chromatin. Divergent genomic binding patterns can also be the result of subtle differences in DNA binding preference between AR and GR. Furthermore, the sequence composition of large regions (>10 kb) surrounding selectively occupied binding sites differs significantly, indicating a role for the sequence environment in guiding AR and GR to distinct binding sites. The comparison of binding sites that are shared shows that the specificity paradox can also be resolved by differences in the events that occur downstream of receptor binding. Specifically, shared binding sites display receptor-specific enhancer activity, cofactor recruitment and changes in histone modifications. Genomic deletion of shared binding sites demonstrates their contribution to directing receptor-specific gene regulation. Together, these data suggest that differences in genomic occupancy as well as divergence in the events that occur downstream of receptor binding direct functional diversification among transcription factor paralogs.
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Affiliation(s)
- Marina Kulik
- Max Planck Institute for Molecular Genetics, Ihnestraße 63–73, 14195 Berlin, Germany
| | - Melissa Bothe
- Max Planck Institute for Molecular Genetics, Ihnestraße 63–73, 14195 Berlin, Germany
| | - Gözde Kibar
- Max Planck Institute for Molecular Genetics, Ihnestraße 63–73, 14195 Berlin, Germany
| | - Alisa Fuchs
- Max Planck Institute for Molecular Genetics, Ihnestraße 63–73, 14195 Berlin, Germany
| | - Stefanie Schöne
- Max Planck Institute for Molecular Genetics, Ihnestraße 63–73, 14195 Berlin, Germany
| | - Stefan Prekovic
- Division of Oncogenomics, Oncode Institute, The Netherlands Cancer Institute, Amsterdam, the Netherlands
| | - Isabel Mayayo-Peralta
- Division of Oncogenomics, Oncode Institute, The Netherlands Cancer Institute, Amsterdam, the Netherlands
| | - Ho-Ryun Chung
- Max Planck Institute for Molecular Genetics, Ihnestraße 63–73, 14195 Berlin, Germany
- Institute for Medical Bioinformatics and Biostatistics, Philipps University of Marburg, 35037, Marburg, Germany
| | - Wilbert Zwart
- Division of Oncogenomics, Oncode Institute, The Netherlands Cancer Institute, Amsterdam, the Netherlands
- Laboratory of Chemical Biology and Institute for Complex Molecular Systems, Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, the Netherlands
| | - Christine Helsen
- Molecular Endocrinology Laboratory, Department of Cellular and Molecular Medicine, KU Leuven, Leuven, Belgium
| | - Frank Claessens
- Molecular Endocrinology Laboratory, Department of Cellular and Molecular Medicine, KU Leuven, Leuven, Belgium
| | - Sebastiaan H Meijsing
- Max Planck Institute for Molecular Genetics, Ihnestraße 63–73, 14195 Berlin, Germany
- Max Planck Unit for the Science of Pathogens, D-10117 Berlin, Germany
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Genome-wide binding potential and regulatory activity of the glucocorticoid receptor's monomeric and dimeric forms. Nat Commun 2021; 12:1987. [PMID: 33790284 PMCID: PMC8012360 DOI: 10.1038/s41467-021-22234-9] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Accepted: 03/05/2021] [Indexed: 02/01/2023] Open
Abstract
A widely regarded model for glucocorticoid receptor (GR) action postulates that dimeric binding to DNA regulates unfavorable metabolic pathways while monomeric receptor binding promotes repressive gene responses related to its anti-inflammatory effects. This model has been built upon the characterization of the GRdim mutant, reported to be incapable of DNA binding and dimerization. Although quantitative live-cell imaging data shows GRdim as mostly dimeric, genomic studies based on recovery of enriched half-site response elements suggest monomeric engagement on DNA. Here, we perform genome-wide studies on GRdim and a constitutively monomeric mutant. Our results show that impairing dimerization affects binding even to open chromatin. We also find that GRdim does not exclusively bind half-response elements. Our results do not support a physiological role for monomeric GR and are consistent with a common mode of receptor binding via higher order structures that drives both the activating and repressive actions of glucocorticoids.
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HUZARD D, RAPPENEAU V, MEIJER OC, TOUMA C, ARANGO-LIEVANO M, GARABEDIAN MJ, JEANNETEAU F. Experience and activity-dependent control of glucocorticoid receptors during the stress response in large-scale brain networks. Stress 2021; 24:130-153. [PMID: 32755268 PMCID: PMC7907260 DOI: 10.1080/10253890.2020.1806226] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
The diversity of actions of the glucocorticoid stress hormones among individuals and within organs, tissues and cells is shaped by age, gender, genetics, metabolism, and the quantity of exposure. However, such factors cannot explain the heterogeneity of responses in the brain within cells of the same lineage, or similar tissue environment, or in the same individual. Here, we argue that the stress response is continuously updated by synchronized neural activity on large-scale brain networks. This occurs at the molecular, cellular and behavioral levels by crosstalk communication between activity-dependent and glucocorticoid signaling pathways, which updates the diversity of responses based on prior experience. Such a Bayesian process determines adaptation to the demands of the body and external world. We propose a framework for understanding how the diversity of glucocorticoid actions throughout brain networks is essential for supporting optimal health, while its disruption may contribute to the pathophysiology of stress-related disorders, such as major depression, and resistance to therapeutic treatments.
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Affiliation(s)
- Damien HUZARD
- Department of Neuroscience and Physiology, University of Montpellier, CNRS, INSERM, Institut de Génomique Fonctionnelle, Montpellier, France
| | - Virginie RAPPENEAU
- Department of Behavioural Biology, University of Osnabrück, Osnabrück, Germany
| | - Onno C. MEIJER
- Division of Endocrinology, Department of Internal Medicine, Leiden University Medical Center, Leiden University, Leiden, the Netherlands
| | - Chadi TOUMA
- Department of Behavioural Biology, University of Osnabrück, Osnabrück, Germany
| | - Margarita ARANGO-LIEVANO
- Department of Neuroscience and Physiology, University of Montpellier, CNRS, INSERM, Institut de Génomique Fonctionnelle, Montpellier, France
| | | | - Freddy JEANNETEAU
- Department of Neuroscience and Physiology, University of Montpellier, CNRS, INSERM, Institut de Génomique Fonctionnelle, Montpellier, France
- Corresponding author:
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Hachemi Y, Rapp AE, Lee S, Dorn AK, Krüger BT, Kaiser K, Ignatius A, Tuckermann J. Intact Glucocorticoid Receptor Dimerization Is Deleterious in Trauma-Induced Impaired Fracture Healing. Front Immunol 2021; 11:628287. [PMID: 33679723 PMCID: PMC7927427 DOI: 10.3389/fimmu.2020.628287] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Accepted: 12/29/2020] [Indexed: 11/13/2022] Open
Abstract
Following severe trauma, fracture healing is impaired because of overwhelming systemic and local inflammation. Glucocorticoids (GCs), acting via the glucocorticoid receptor (GR), influence fracture healing by modulating the trauma-induced immune response. GR dimerization-dependent gene regulation is essential for the anti-inflammatory effects of GCs. Therefore, we investigated in a murine trauma model of combined femur fracture and thoracic trauma, whether effective GR dimerization influences the pathomechanisms of trauma-induced compromised fracture healing. To this end, we used mice with decreased GR dimerization ability (GRdim). The healing process was analyzed by cytokine/chemokine multiplex analysis, flow cytometry, gene-expression analysis, histomorphometry, micro-computed tomography, and biomechanical testing. GRdim mice did not display a systemic or local hyper-inflammation upon combined fracture and thorax trauma. Strikingly, we discovered that GRdim mice were protected from fracture healing impairment induced by the additional thorax trauma. Collectively and in contrast to previous studies describing the beneficial effects of intact GR dimerization in inflammatory models, we report here an adverse role of intact GR dimerization in trauma-induced compromised fracture healing.
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Affiliation(s)
- Yasmine Hachemi
- Institute of Comparative Molecular Endocrinology, Ulm University, Ulm, Germany
| | - Anna E Rapp
- Institute of Orthopedic Research and Biomechanics, Ulm University Medical Center, Ulm, Germany
| | - Sooyeon Lee
- Institute of Comparative Molecular Endocrinology, Ulm University, Ulm, Germany
| | - Ann-Kristin Dorn
- Institute of Comparative Molecular Endocrinology, Ulm University, Ulm, Germany
| | - Benjamin T Krüger
- Institute of Orthopedic Research and Biomechanics, Ulm University Medical Center, Ulm, Germany
| | - Kathrin Kaiser
- Institute of Orthopedic Research and Biomechanics, Ulm University Medical Center, Ulm, Germany
| | - Anita Ignatius
- Institute of Orthopedic Research and Biomechanics, Ulm University Medical Center, Ulm, Germany
| | - Jan Tuckermann
- Institute of Comparative Molecular Endocrinology, Ulm University, Ulm, Germany
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León B, Ballesteros-Tato A. Modulating Th2 Cell Immunity for the Treatment of Asthma. Front Immunol 2021; 12:637948. [PMID: 33643321 PMCID: PMC7902894 DOI: 10.3389/fimmu.2021.637948] [Citation(s) in RCA: 73] [Impact Index Per Article: 24.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Accepted: 01/21/2021] [Indexed: 12/14/2022] Open
Abstract
It is estimated that more than 339 million people worldwide suffer from asthma. The leading cause of asthma development is the breakdown of immune tolerance to inhaled allergens, prompting the immune system's aberrant activation. During the early phase, also known as the sensitization phase, allergen-specific T cells are activated and become central players in orchestrating the subsequent development of allergic asthma following secondary exposure to the same allergens. It is well-established that allergen-specific T helper 2 (Th2) cells play central roles in developing allergic asthma. As such, 80% of children and 60% of adult asthma cases are linked to an unwarranted Th2 cell response against respiratory allergens. Thus, targeting essential components of Th2-type inflammation using neutralizing antibodies against key Th2 modulators has recently become an attractive option for asthmatic patients with moderate to severe symptoms. In addition to directly targeting Th2 mediators, allergen immunotherapy, also known as desensitization, is focused on redirecting the allergen-specific T cells response from a Th2-type profile to a tolerogenic one. This review highlights the current understanding of the heterogeneity of the Th2 cell compartment, their contribution to allergen-induced airway inflammation, and the therapies targeting the Th2 cell pathway in asthma. Further, we discuss available new leads for successful targeting pulmonary Th2 cell responses for future therapeutics.
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Affiliation(s)
- Beatriz León
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Andre Ballesteros-Tato
- Division of Clinical Immunology and Rheumatology, Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, United States
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Reduced Expression of Antimicrobial Protein Secretory Leukoprotease Inhibitor and Clusterin in Chronic Rhinosinusitis with Nasal Polyps. J Immunol Res 2021; 2021:1057186. [PMID: 33506054 PMCID: PMC7810533 DOI: 10.1155/2021/1057186] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2020] [Revised: 12/20/2020] [Accepted: 12/24/2020] [Indexed: 12/13/2022] Open
Abstract
Introduction Antimicrobial peptides and proteins (AMPs) constitute the first line of defense against pathogenic microorganisms in the airway. The association between AMPs and chronic rhinosinusitis with nasal polyps (CRSwNP) requires further investigations. This study is aimed at investigating the expression and regulation of major dysregulated AMPs in the nasal mucosa of CRSwNP. Methods The expression of AMPs was analyzed in nasal tissue from patients with eosinophilic (E) CRSwNP and nonECRSwNP and healthy subjects using RNA sequencing. The 10 most abundant AMPs expressed differentially in CRSwNP patients were verified by real-time PCR, and of these, the expression and regulation of secretory leukoprotease inhibitor (SLPI) and clusterin (CLU) were investigated further. Results The 10 most abundant AMPs expressed differentially in CRSwNP compared to healthy control, regardless of subtypes, included BPIFA1, BPIFB1, BPIFB2, CLU, LTF, LYZ, and SLPI, which were downregulated, and S100A8, S100A9, and HIST1H2BC, which were upregulated. ELISA and immunofluorescence confirmed the decreased expression of SLPI and CLU levels in CRSwNP. SLPI is expressed in both nasal epithelial cells and glandular cells, whereas CLU is mainly expressed in glandular cells. AB/PAS staining further demonstrated that both SLPI and CLU were mainly produced by mucous cells in submucosal glands. Furthermore, the numbers of submucosal glands were significantly decreased in nasal polyp tissue of CRSwNP compared to nasal tissue of controls. SLPI was downregulated by TGF-β1 and IL-4 in cultured nasal tissues in vitro, while CLU expression was inhibited by TGF-β1. Glucocorticoid treatment for 2 weeks significantly increased the expression of all downregulated AMPs, but not LYZ. Additionally, budesonide significantly increased the expression of SLPI and CLU in cultured nasal tissues. Conclusion The expression of major antimicrobial proteins is significantly decreased in nasal tissue of CRSwNP. The expression of SLPI and CLU is correlated with the numbers of submucosal glands and regulated by inflammatory cytokines and glucocorticoids.
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Sawant L, Thunuguntla P, Jones C. Cooperative activation of bovine herpesvirus 1 productive infection and viral regulatory promoters by androgen receptor and Krüppel-like transcription factors 4 and 15. Virology 2021; 552:63-72. [PMID: 33065464 DOI: 10.1016/j.virol.2020.08.015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 08/12/2020] [Accepted: 08/28/2020] [Indexed: 01/01/2023]
Abstract
Bovine herpesvirus 1 (BoHV-1), a significant viral pathogen, establishes latency in sensory neurons. The viral genome contains more than 100 consensus glucocorticoid receptor (GR) regulatory elements (GREs): consequently, stress stimulates viral replication and reactivation from latency. The immediate early transcription unit 1 (IEtu1) and bICP0 early promoters are transactivated by GR and synthetic corticosteroid dexamethasone. The androgen receptor (AR), like GR, is a Type 1 nuclear hormone receptor that binds and stimulates certain promoters containing GREs. Consequently, we hypothesized AR and 5α-Dihydrotestosterone (DHT) stimulate productive infection and key viral promoters. New studies demonstrated AR, DHT, and Krüppel like transcription factor 4 (KLF4) cooperatively stimulated productive infection and bICP0 E promoter activity in mouse neuroblastoma cells (Neuro-2A). KLF15 also cooperated with AR and DHT to stimulate IEtu1 promoter activity. We suggest AR and testosterone increase the prevalence of virus in semen by stimulating viral gene expression and replication.
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Affiliation(s)
- Laximan Sawant
- Oklahoma State University, Center for Veterinary Health Sciences, Department of Veterinary Pathobiology, Stillwater, OK, USA
| | - Prasanth Thunuguntla
- Oklahoma State University, Center for Veterinary Health Sciences, Department of Veterinary Pathobiology, Stillwater, OK, USA
| | - Clinton Jones
- Oklahoma State University, Center for Veterinary Health Sciences, Department of Veterinary Pathobiology, Stillwater, OK, USA.
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Podgorny OV, Gulyaeva NV. Glucocorticoid-mediated mechanisms of hippocampal damage: Contribution of subgranular neurogenesis. J Neurochem 2020; 157:370-392. [PMID: 33301616 DOI: 10.1111/jnc.15265] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Revised: 11/09/2020] [Accepted: 11/30/2020] [Indexed: 12/19/2022]
Abstract
A comprehensive overview of the interplay between glucocorticoids (GCs) and adult hippocampal neurogenesis (AHN) is presented, particularly, in the context of a diseased brain. The effectors of GCs in the dentate gyrus neurogenic niche of the hippocampal are reviewed, and the consequences of the GC signaling on the generation and integration of new neurons are discussed. Recent findings demonstrating how GC signaling mediates impairments of the AHN in various brain pathologies are overviewed. GC-mediated effects on the generation and integration of adult-born neurons in the hippocampal dentate gyrus depend on the nature, severity, and duration of the acting stress factor. GCs realize their effects on the AHN primarily via specific glucocorticoid and mineralocorticoid receptors. Disruption of the reciprocal regulation between the hypothalamic-pituitary-adrenal (HPA) axis and the generation of the adult-born granular neurons is currently considered to be a key mechanism implicating the AHN into the pathogenesis of numerous brain diseases, including those without a direct hippocampal damage. These alterations vary from reduced proliferation of stem and progenitor cells to increased cell death and abnormalities in morphology, connectivity, and localization of young neurons. Although the involvement of the mutual regulation between the HPA axis and the AHN in the pathogenesis of cognitive deficits and mood impairments is evident, several unresolved critical issues are stated. Understanding the details of GC-mediated mechanisms involved in the alterations in AHN could enable the identification of molecular targets for ameliorating pathology-induced imbalance in the HPA axis/AHN mutual regulation to conquer cognitive and psychiatric disturbances.
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Affiliation(s)
- Oleg V Podgorny
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia.,Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Pirogov Russian National Research Medical University, Moscow, Russia.,Koltzov Institute of Developmental Biology, Russian Academy of Sciences, Moscow, Russia
| | - Natalia V Gulyaeva
- Institute of Higher Nervous Activity and Neurophysiology, Russian Academy of Sciences, Moscow, Russia.,Research and Clinical Center for Neuropsychiatry of Moscow Healthcare Department, Moscow, Russia
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Wepler M, Preuss JM, Merz T, McCook O, Radermacher P, Tuckermann JP, Vettorazzi S. Impact of downstream effects of glucocorticoid receptor dysfunction on organ function in critical illness-associated systemic inflammation. Intensive Care Med Exp 2020; 8:37. [PMID: 33336296 PMCID: PMC7746781 DOI: 10.1186/s40635-020-00325-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Accepted: 07/14/2020] [Indexed: 12/20/2022] Open
Abstract
Glucocorticoids (GCs) are stress hormones that regulate developmental and physiological processes and are among the most potent anti-inflammatory drugs to suppress chronic and acute inflammation. GCs act through the glucocorticoid receptor (GR), a ubiquitously expressed ligand-activated transcription factor, which translocates into the nucleus and can act via two different modes, as a GR monomer or as a GR dimer. These two modes of action are not clearly differentiated in practice and may lead to completely different therapeutic outcomes. Detailed aspects of GR mechanisms are often not taken into account when GCs are used in different clinical scenarios. Patients, with critical illness-related corticosteroid insufficiency, treated with natural or synthetic GCs are still missing a clearly defined therapeutic strategy. This review discusses the different modes of GR function and its importance on organ function in vivo.
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Affiliation(s)
- Martin Wepler
- Institute for Anesthesiological Pathophysiology and Process Engineering, University Hospital Ulm, Ulm, Germany. .,Department of Anesthesia, University Hospital Ulm, Ulm, Germany.
| | - Jonathan M Preuss
- Institute of Comparative Molecular Endocrinology (CME), Ulm University, Ulm, Germany
| | - Tamara Merz
- Institute for Anesthesiological Pathophysiology and Process Engineering, University Hospital Ulm, Ulm, Germany
| | - Oscar McCook
- Institute for Anesthesiological Pathophysiology and Process Engineering, University Hospital Ulm, Ulm, Germany
| | - Peter Radermacher
- Institute for Anesthesiological Pathophysiology and Process Engineering, University Hospital Ulm, Ulm, Germany
| | - Jan P Tuckermann
- Institute of Comparative Molecular Endocrinology (CME), Ulm University, Ulm, Germany
| | - Sabine Vettorazzi
- Institute of Comparative Molecular Endocrinology (CME), Ulm University, Ulm, Germany
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Yang M, Chen J, Wei W. Dimerization of glucocorticoid receptors and its role in inflammation and immune responses. Pharmacol Res 2020; 166:105334. [PMID: 33276107 DOI: 10.1016/j.phrs.2020.105334] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Revised: 11/18/2020] [Accepted: 11/27/2020] [Indexed: 12/19/2022]
Abstract
Glucocorticoids (GCs) plays an irreplaceable role in inflammation and immune responses, fat metabolism and sugar metabolism, it is often used for the treatment of asthma, rheumatoid arthritis and allergic rhinitis clinically, but long-term or high-dose use will produce adverse drug reactions (ADRs). Its biological action is mediated by glucocorticoid receptors (GRs), of which the oligomerization state is closely related to the target gene of which the GRs act. A leading hypothesis is that the beneficial anti-inflammatory effects of GCs occur through the transrepression mechanism mediated by GR monomers, while ADRs may be dependent on the transactivation mechanism mediated by GR dimers. However, in recent years, multiple studies have shown that the transactivation and transrepression functions of the GR dimer also confer anti-inflammatory effects. Furthermore, some studies have shown that some selective glucocorticoid receptor agonists and modulators (SEGRAMs) have good separation characteristics (i.e., preferentially mediate the transrepression of proinflammatory genes or preferentially activate anti-inflammatory target genes). This article reviewed the formation of GR dimers, the role of GR dimers in the inflammation and immune responses, and the progress of SEGRAMs to provide novel ideas for further understanding the anti-inflammatory mechanism of GR and the development of SEGRAMs.
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Affiliation(s)
- Mei Yang
- Institute of Clinical Pharmacology, Anhui Medical University, Key Laboratory of Anti-Inflammatory and Immune Medicine, Ministry of Education, Anhui Collaborative Innovation Center of Anti-Inflammatory and Immune Medicine, Meishan Road 81, Hefei, 230032, China
| | - Jingyu Chen
- Institute of Clinical Pharmacology, Anhui Medical University, Key Laboratory of Anti-Inflammatory and Immune Medicine, Ministry of Education, Anhui Collaborative Innovation Center of Anti-Inflammatory and Immune Medicine, Meishan Road 81, Hefei, 230032, China.
| | - Wei Wei
- Institute of Clinical Pharmacology, Anhui Medical University, Key Laboratory of Anti-Inflammatory and Immune Medicine, Ministry of Education, Anhui Collaborative Innovation Center of Anti-Inflammatory and Immune Medicine, Meishan Road 81, Hefei, 230032, China.
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Specific Akt Family Members Impair Stress-Mediated Transactivation of Viral Promoters and Enhance Neuronal Differentiation: Important Functions for Maintaining Latency. J Virol 2020; 94:JVI.00901-20. [PMID: 32796067 DOI: 10.1128/jvi.00901-20] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Accepted: 07/30/2020] [Indexed: 01/02/2023] Open
Abstract
Neurotropic Alphaherpesvirinae subfamily members such as bovine herpesvirus 1 (BoHV-1) and herpes simplex virus 1 (HSV-1) establish and maintain lifelong latent infections in neurons. Following infection of ocular, oral, or nasal cavities, sensory neurons within trigeminal ganglia (TG) are an important site for latency. Certain external stressors can trigger reactivation from latency, in part because activation of the glucocorticoid receptor (GR) stimulates productive infection and promoters that drive expression of key viral transcriptional regulators. The Akt serine/threonine protein kinase family is linked to maintaining latency. For example, Akt3 is detected in more TG neurons during BoHV-1 latency than in reactivation and uninfected calves. Furthermore, Akt signaling correlates with maintaining HSV-1 latency in certain neuronal models of latency. Finally, an active Akt protein kinase is crucial for the ability of the HSV-1 latency-associated transcript (LAT) to inhibit apoptosis in neuronal cell lines. Consequently, we hypothesized that viral and/or cellular factors impair stress-induced transcription and reduce the incidence of reactivation triggered by low levels of stress. New studies demonstrate that Akt1 and Akt2, but not Akt3, significantly reduced GR-mediated transactivation of the BoHV-1 immediate early transcription unit 1 (IEtu1) promoter, the HSV-1 infected cell protein 0 (ICP0) promoter, and the mouse mammary tumor virus long terminal repeat (MMTV-LTR). Akt3, but not Akt1 or Akt2, significantly enhanced neurite formation in mouse neuroblastoma cells, which correlates with repairing damaged neurons. These studies suggest that unique biological properties of the three Akt family members promote the maintenance of latency in differentiated neurons.IMPORTANCE External stressful stimuli are known to increase the incidence of reactivation of Alphaherpesvirinae subfamily members. Activation of the glucocorticoid receptor (GR) by the synthetic corticosteroid dexamethasone (DEX) stimulates bovine herpesvirus 1 (BoHV-1) and herpes simplex virus 1 (HSV-1) reactivation. Furthermore, GR and dexamethasone stimulate productive infection and promoters that drive expression of viral transcriptional regulators. These observations lead us to predict that stress-induced transcription is impaired by factors abundantly expressed during latency. Interestingly, activation of the Akt family of serine/threonine protein kinases is linked to maintenance of latency. New studies reveal that Akt1 and Ak2, but not Akt3, impaired GR- and dexamethasone-mediated transactivation of the BoHV-1 immediate early transcription unit 1 and HSV-1 ICP0 promoters. Strikingly, Akt3, but not Akt1 or Akt2, stimulated neurite formation in mouse neuroblastoma cells, a requirement for neurogenesis. These studies provide insight into how Akt family members may promote the maintenance of lifelong latency.
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Præstholm SM, Correia CM, Grøntved L. Multifaceted Control of GR Signaling and Its Impact on Hepatic Transcriptional Networks and Metabolism. Front Endocrinol (Lausanne) 2020; 11:572981. [PMID: 33133019 PMCID: PMC7578419 DOI: 10.3389/fendo.2020.572981] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Accepted: 09/03/2020] [Indexed: 12/14/2022] Open
Abstract
Glucocorticoids (GCs) and the glucocorticoid receptor (GR) are important regulators of development, inflammation, stress response and metabolism, demonstrated in various diseases including Addison's disease, Cushing's syndrome and by the many side effects of prolonged clinical administration of GCs. These conditions include severe metabolic challenges in key metabolic organs like the liver. In the liver, GR is known to regulate the transcription of key enzymes in glucose and lipid metabolism and contribute to the regulation of circadian-expressed genes. Insights to the modes of GR regulation and the underlying functional mechanisms are key for understanding diseases and for the development of improved clinical uses of GCs. The activity and function of GR is regulated at numerous levels including ligand availability, interaction with heat shock protein (HSP) complexes, expression of GR isoforms and posttranslational modifications. Moreover, recent genomics studies show functional interaction with multiple transcription factors (TF) and coregulators in complex transcriptional networks controlling cell type-specific gene expression by GCs. In this review we describe the different regulatory steps important for GR activity and discuss how different TF interaction partners of GR selectively control hepatic gene transcription and metabolism.
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Affiliation(s)
| | | | - Lars Grøntved
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense, Denmark
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43
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Sawant L, Wijesekera N, Jones C. Pioneer transcription factors, progesterone receptor and Krüppel like transcription factor 4, cooperatively stimulate the bovine herpesvirus 1 ICP0 early promoter and productive late protein expression. Virus Res 2020; 288:198115. [PMID: 32795492 DOI: 10.1016/j.virusres.2020.198115] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 08/05/2020] [Accepted: 08/06/2020] [Indexed: 12/15/2022]
Abstract
Bovine herpesvirus 1 (BoHV-1), including commercially available modified live vaccines, readily infect the fetus and ovaries, which can cause reproductive failure. The BoHV-1 latency-reactivation cycle in sensory neurons further complicates reproductive failure because progesterone sporadically induces reactivation from latency. The progesterone receptor (PR) and Krüppel-like transcription factor 15 (KLF15) cooperatively stimulate productive infection and the immediate early transcription unit 1 (IEtu1) promoter. In addition to the IEtu1 promoter, the bICP0 gene also contains a separate early (E) promoter. In this study, we tested the hypothesis that PR and KLF family members transactivate the bICP0 E promoter. PR and KLF4 stimulated bICP0 E promoter activity and expression of late productive viral protein expression in a cooperative manner. Additional studies revealed three enhancer domains within the bICP0 E promoter were responsive to PR and KLF4. Chromatin immunoprecipitation studies demonstrated PR and KLF4 occupy bICP0 E promoter sequences in transfected Neuro-2A cells and at late times following infection of bovine kidney cells. Co-immunoprecipitation studies indicated PR and KLF4 stably interact with each other. These studies suggest cooperative activation of the bICP0 E promoter by PR and KLF4 correlate with interactions between these pioneer transcription factors.
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Affiliation(s)
- Laximan Sawant
- Oklahoma State University, College of Veterinary Medicine, Department of Veterinary Pathobiology, Stillwater, OK 74078, United States
| | - Nishani Wijesekera
- Oklahoma State University, College of Veterinary Medicine, Department of Veterinary Pathobiology, Stillwater, OK 74078, United States
| | - Clinton Jones
- Oklahoma State University, College of Veterinary Medicine, Department of Veterinary Pathobiology, Stillwater, OK 74078, United States.
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Kershaw S, Morgan DJ, Boyd J, Spiller DG, Kitchen G, Zindy E, Iqbal M, Rattray M, Sanderson CM, Brass A, Jorgensen C, Hussell T, Matthews LC, Ray DW. Glucocorticoids rapidly inhibit cell migration through a novel, non-transcriptional HDAC6 pathway. J Cell Sci 2020; 133:jcs242842. [PMID: 32381682 PMCID: PMC7295589 DOI: 10.1242/jcs.242842] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Accepted: 04/21/2020] [Indexed: 12/12/2022] Open
Abstract
Glucocorticoids (GCs) act through the glucocorticoid receptor (GR, also known as NR3C1) to regulate immunity, energy metabolism and tissue repair. Upon ligand binding, activated GR mediates cellular effects by regulating gene expression, but some GR effects can occur rapidly without new transcription. Here, we show that GCs rapidly inhibit cell migration, in response to both GR agonist and antagonist ligand binding. The inhibitory effect on migration is prevented by GR knockdown with siRNA, confirming GR specificity, but not by actinomycin D treatment, suggesting a non-transcriptional mechanism. We identified a rapid onset increase in microtubule polymerisation following GC treatment, identifying cytoskeletal stabilisation as the likely mechanism of action. HDAC6 overexpression, but not knockdown of αTAT1, rescued the GC effect, implicating HDAC6 as the GR effector. Consistent with this hypothesis, ligand-dependent cytoplasmic interaction between GR and HDAC6 was demonstrated by quantitative imaging. Taken together, we propose that activated GR inhibits HDAC6 function, and thereby increases the stability of the microtubule network to reduce cell motility. We therefore report a novel, non-transcriptional mechanism whereby GCs impair cell motility through inhibition of HDAC6 and rapid reorganization of the cell architecture.This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Stephen Kershaw
- Systems Oncology, Cancer Research UK Manchester Institute, Manchester, SK10 4TG, UK
| | - David J Morgan
- Manchester Collaborative Centre for Inflammation Research, University of Manchester, Manchester, M13 9PT, UK
- Lydia Becker Institute of Immunology and Inflammation University of Manchester, Manchester, M13 9PT, UK
| | - James Boyd
- Division of Cellular and Molecular Physiology, University of Liverpool, Liverpool, L69 3BX, UK
| | - David G Spiller
- Platform Sciences, Enabling Technologies, and Infrastructure, University of Manchester, Manchester, M13 9PT, UK
| | - Gareth Kitchen
- Division of Diabetes, Endocrinology, and Gastroenterology, University of Manchester, Manchester, M13 9PT, UK
| | - Egor Zindy
- Division of Informatics, Imaging, and Data Sciences, Faculty of Biology, Medicine, and Health, University of Manchester, Manchester, M13 9PT, UK
| | - Mudassar Iqbal
- Division of Informatics, Imaging, and Data Sciences, Faculty of Biology, Medicine, and Health, University of Manchester, Manchester, M13 9PT, UK
| | - Magnus Rattray
- Division of Informatics, Imaging, and Data Sciences, Faculty of Biology, Medicine, and Health, University of Manchester, Manchester, M13 9PT, UK
| | - Christopher M Sanderson
- Division of Cellular and Molecular Physiology, University of Liverpool, Liverpool, L69 3BX, UK
| | - Andrew Brass
- Division of Informatics, Imaging, and Data Sciences, Faculty of Biology, Medicine, and Health, University of Manchester, Manchester, M13 9PT, UK
| | - Claus Jorgensen
- Systems Oncology, Cancer Research UK Manchester Institute, Manchester, SK10 4TG, UK
| | - Tracy Hussell
- Manchester Collaborative Centre for Inflammation Research, University of Manchester, Manchester, M13 9PT, UK
- Lydia Becker Institute of Immunology and Inflammation University of Manchester, Manchester, M13 9PT, UK
| | - Laura C Matthews
- Leeds Institute of Cancer and Pathology, Faculty of Medicine and Health, University of Leeds, Leeds, LS2 9JT, UK
| | - David W Ray
- Division of Diabetes, Endocrinology, and Gastroenterology, University of Manchester, Manchester, M13 9PT, UK
- Oxford Centre for Diabetes, Endocrinology and Metabolism (OCDEM), University of Oxford, OX3 7LE, and NIHR Oxford Biomedical Research Centre, John Radcliffe Hospital, Oxford, OX3 9DU, UK
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Lucafò M, Franzin M, Decorti G, Stocco G. A patent review of anticancer glucocorticoid receptor modulators (2014-present). Expert Opin Ther Pat 2020; 30:313-324. [PMID: 32148111 DOI: 10.1080/13543776.2020.1740206] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Introduction: Natural and synthetic glucocorticoids are widely employed in different diseases, among which are hematological and solid tumors. Their use is however associated with a number of serious side effects and by the occurrence of resistance. With the aim of separating their gene transactivating effect, more linked to side effects, from transrepressive properties, associated with therapeutic efficacy, a number of selective glucocorticoid modulators have been identified.Areas covered: This review summarizes the patent applications from 2014 to present in the field of selective glucocorticoid receptor modulators employed in cancer therapy. Only few patents have been identified, that concern the identification of new molecules or the method of use of already patented compounds. In addition, a discussion of the mechanism of action of these compounds is included.Expert opinion: Only a very limited number of patents have been applied that concern selective glucocorticoid receptor modulators and their use in cancer. Biological information is scarce for most of these patents; more research is necessary in this field in particular concerning clinical data in order to understand whether it is actually possible to improve the efficacy and therapeutic index of these compounds in cancer therapy.
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Affiliation(s)
- Marianna Lucafò
- Institute for Maternal and Child Health I.R.C.C.S. Burlo Garofolo, Trieste, Italy
| | - Martina Franzin
- PhD Course in Reproductive and Developmental Sciences, University of Trieste, Trieste, Italy
| | - Giuliana Decorti
- Institute for Maternal and Child Health I.R.C.C.S. Burlo Garofolo, Trieste, Italy.,Department of Medical, Surgical and Health Sciences, University of Trieste, Trieste, Italy
| | - Gabriele Stocco
- Department of Life Sciences, University of Trieste, Trieste, Italy
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Two Pioneer Transcription Factors, Krüppel-Like Transcription Factor 4 and Glucocorticoid Receptor, Cooperatively Transactivate the Bovine Herpesvirus 1 ICP0 Early Promoter and Stimulate Productive Infection. J Virol 2020; 94:JVI.01670-19. [PMID: 31776270 DOI: 10.1128/jvi.01670-19] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Accepted: 11/14/2019] [Indexed: 12/13/2022] Open
Abstract
An important site for bovine herpesvirus 1 (BoHV-1) latency is sensory neurons within trigeminal ganglia (TG). The synthetic corticosteroid dexamethasone consistently induces BoHV-1 reactivation from latency. Expression of four Krüppel-like transcription factors (KLF), i.e., KLF4, KLF6, PLZF (promyelocytic leukemia zinc finger), and KLF15, are induced in TG neurons early during dexamethasone-induced reactivation. The glucocorticoid receptor (GR) and KLF15 form a feed-forward transcription loop that cooperatively transactivates the BoHV-1 immediate early transcription unit 1 (IEtu1) promoter that drives bovine infected cell protein 0 (bICP0) and bICP4 expression. Since the bICP0 gene also contains a separate early (E) promoter, we tested the hypothesis that GR and KLF family members transactivate the bICP0 E promoter. GR and KLF4, both pioneer transcription factors, cooperated to stimulate bICP0 E promoter activity in a ligand-independent manner in mouse neuroblastoma cells (Neuro-2A). Furthermore, GR and KLF4 stimulated productive infection. Mutating both half GR binding sites did not significantly reduce GR- and KLF4-mediated transactivation of the bICP0 E promoter, suggesting that a novel mechanism exists for transactivation. GR and KLF15 cooperatively stimulated bICP0 activity less efficiently than GR and KL4: however, KLF6, PLZF, and GR had little effect on the bICP0 E promoter. GR, KLF4, and KLF15 occupied bICP0 E promoter sequences in transfected Neuro-2A cells. GR and KLF15, but not KLF4, occupied the bICP0 E promoter at late times during productive infection of bovine cells. Collectively, these studies suggest that cooperative transactivation of the bICP0 E promoter by two pioneer transcription factors (GR and KLF4) correlates with stimulating lytic cycle viral gene expression following stressful stimuli.IMPORTANCE Bovine herpesvirus 1 (BoHV-1), an important bovine pathogen, establishes lifelong latency in sensory neurons. Reactivation from latency is consistently induced by the synthetic corticosteroid dexamethasone. We predict that increased corticosteroid levels activate the glucocorticoid receptor (GR). Consequently, viral gene expression is stimulated by the activated GR. The immediate early transcription unit 1 promoter (IEtu1) drives expression of two viral transcriptional regulatory proteins, bovine infected cell protein 0 (bICP0) and bICP4. Interestingly, a separate early promoter also drives bICP0 expression. Two pioneer transcription factors, GR and Krüppel-like transcription factor 4 (KLF4), cooperatively transactivate the bICP0 early (E) promoter. GR and KLF15 cooperate to stimulate bICP0 E promoter activity but significantly less than GR and KLF4. The bICP0 E promoter contains enhancer-like domains necessary for GR- and KLF4-mediated transactivation that are distinct from those for GR and KLF15. Stress-induced pioneer transcription factors are proposed to activate key viral promoters, including the bICP0 E promoter, during early stages of reactivation from latency.
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Parsonnet NV, Lammer NC, Holmes ZE, Batey RT, Wuttke DS. The glucocorticoid receptor DNA-binding domain recognizes RNA hairpin structures with high affinity. Nucleic Acids Res 2019; 47:8180-8192. [PMID: 31147715 DOI: 10.1093/nar/gkz486] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Revised: 05/17/2019] [Accepted: 05/21/2019] [Indexed: 01/04/2023] Open
Abstract
The glucocorticoid receptor (GR) binds the noncoding RNA Gas5 via its DNA-binding domain (DBD) with functional implications in pro-apoptosis signaling. Here, we report a comprehensive in vitro binding study where we have determined that GR-DBD is a robust structure-specific RNA-binding domain. GR-DBD binds to a diverse range of RNA hairpin motifs, both synthetic and biologically derived, with apparent mid-nanomolar affinity while discriminating against uniform dsRNA. As opposed to dimeric recognition of dsDNA, GR-DBD binds to RNA as a monomer and confers high affinity primarily through electrostatic contacts. GR-DBD adopts a discrete RNA-bound state, as assessed by NMR, distinct from both free and DNA-bound. NMR and alanine mutagenesis suggest a heightened involvement of the C-terminal α-helix of the GR-DBD in RNA-binding. RNA competes for binding with dsDNA and occurs in a similar affinity range as dimer binding to the canonical DNA element. Given the prevalence of RNA hairpins within the transcriptome, our findings strongly suggest that many RNAs have potential to impact GR biology.
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Affiliation(s)
- Nicholas V Parsonnet
- Department of Biochemistry, University of Colorado at Boulder, Campus Box 596, Boulder, CO 80309-0596, USA
| | - Nickolaus C Lammer
- Department of Biochemistry, University of Colorado at Boulder, Campus Box 596, Boulder, CO 80309-0596, USA
| | - Zachariah E Holmes
- Department of Biochemistry, University of Colorado at Boulder, Campus Box 596, Boulder, CO 80309-0596, USA
| | - Robert T Batey
- Department of Biochemistry, University of Colorado at Boulder, Campus Box 596, Boulder, CO 80309-0596, USA
| | - Deborah S Wuttke
- Department of Biochemistry, University of Colorado at Boulder, Campus Box 596, Boulder, CO 80309-0596, USA
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The shift in the balance between osteoblastogenesis and adipogenesis of mesenchymal stem cells mediated by glucocorticoid receptor. Stem Cell Res Ther 2019; 10:377. [PMID: 31805987 PMCID: PMC6896503 DOI: 10.1186/s13287-019-1498-0] [Citation(s) in RCA: 84] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2019] [Revised: 11/09/2019] [Accepted: 11/18/2019] [Indexed: 12/31/2022] Open
Abstract
Mesenchymal stem cells (MSCs) are multipotent cells capable of differentiating into several tissues, such as bone, cartilage, and fat. Glucocorticoids affect a variety of biological processes such as proliferation, differentiation, and apoptosis of various cell types, including osteoblasts, adipocytes, or chondrocytes. Glucocorticoids exert their function by binding to the glucocorticoid receptor (GR). Physiological concentrations of glucocorticoids stimulate osteoblast proliferation and promote osteogenic differentiation of MSCs. However, pharmacological concentrations of glucocorticoids can not only induce apoptosis of osteoblasts and osteocytes but can also reduce proliferation and inhibit the differentiation of osteoprogenitor cells. Several signaling pathways, including the Wnt, TGFβ/BMP superfamily and Notch signaling pathways, transcription factors, post-transcriptional regulators, and other regulators, regulate osteoblastogenesis and adipogenesis of MSCs mediated by GR. These signaling pathways target key transcription factors, such as Runx2 and TAZ for osteogenesis and PPARγ and C/EBPs for adipogenesis. Glucocorticoid-induced osteonecrosis and osteoporosis are caused by various factors including dysfunction of bone marrow MSCs. Transplantation of MSCs is valuable in regenerative medicine for the treatment of osteonecrosis of the femoral head, osteoporosis, osteogenesis imperfecta, and other skeletal disorders. However, the mechanism of inducing MSCs to differentiate toward the osteogenic lineage is the key to an efficient treatment. Thus, a better understanding of the molecular mechanisms behind the imbalance between GR-mediated osteoblastogenesis and adipogenesis of MSCs would not only help us to identify the pathogenic causes of glucocorticoid-induced osteonecrosis and osteoporosis but also promote future clinical applications for stem cell-based tissue engineering and regenerative medicine. Here, we primarily review the signaling mechanisms involved in adipogenesis and osteogenesis mediated by GR and discuss the factors that control the adipo-osteogenic balance.
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Escoter-Torres L, Caratti G, Mechtidou A, Tuckermann J, Uhlenhaut NH, Vettorazzi S. Fighting the Fire: Mechanisms of Inflammatory Gene Regulation by the Glucocorticoid Receptor. Front Immunol 2019; 10:1859. [PMID: 31440248 PMCID: PMC6693390 DOI: 10.3389/fimmu.2019.01859] [Citation(s) in RCA: 77] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Accepted: 07/23/2019] [Indexed: 12/12/2022] Open
Abstract
For many decades, glucocorticoids have been widely used as the gold standard treatment for inflammatory conditions. Unfortunately, their clinical use is limited by severe adverse effects such as insulin resistance, cardiometabolic diseases, muscle and skin atrophies, osteoporosis, and depression. Glucocorticoids exert their effects by binding to the Glucocorticoid Receptor (GR), a ligand-activated transcription factor which both positively, and negatively regulates gene expression. Extensive research during the past several years has uncovered novel mechanisms by which the GR activates and represses its target genes. Genome-wide studies and mouse models have provided valuable insight into the molecular mechanisms of inflammatory gene regulation by GR. This review focusses on newly identified target genes and GR co-regulators that are important for its anti-inflammatory effects in innate immune cells, as well as mutations within the GR itself that shed light on its transcriptional activity. This research progress will hopefully serve as the basis for the development of safer immune suppressants with reduced side effect profiles.
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Affiliation(s)
- Laura Escoter-Torres
- Molecular Endocrinology, Helmholtz Zentrum München (HMGU), German Center for Diabetes Research (DZD), Institute for Diabetes and Cancer IDC, Munich, Germany
| | - Giorgio Caratti
- Department of Biology, Institute for Comparative Molecular Endocrinology, University of Ulm, Ulm, Germany
| | - Aikaterini Mechtidou
- Molecular Endocrinology, Helmholtz Zentrum München (HMGU), German Center for Diabetes Research (DZD), Institute for Diabetes and Cancer IDC, Munich, Germany
| | - Jan Tuckermann
- Department of Biology, Institute for Comparative Molecular Endocrinology, University of Ulm, Ulm, Germany
| | - Nina Henriette Uhlenhaut
- Molecular Endocrinology, Helmholtz Zentrum München (HMGU), German Center for Diabetes Research (DZD), Institute for Diabetes and Cancer IDC, Munich, Germany.,Gene Center, Ludwig-Maximilians-Universität (LMU), Munich, Germany
| | - Sabine Vettorazzi
- Department of Biology, Institute for Comparative Molecular Endocrinology, University of Ulm, Ulm, Germany
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50
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Louw A. GR Dimerization and the Impact of GR Dimerization on GR Protein Stability and Half-Life. Front Immunol 2019; 10:1693. [PMID: 31379877 PMCID: PMC6653659 DOI: 10.3389/fimmu.2019.01693] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Accepted: 07/08/2019] [Indexed: 12/14/2022] Open
Abstract
Pharmacologically, glucocorticoids, which mediate their effects via the glucocorticoid receptor (GR), are a most effective therapy for inflammatory diseases despite the fact that chronic use causes side-effects and acquired GC resistance. The design of drugs with fewer side-effects and less potential for the development of resistance is therefore considered crucial for improved therapy. Dimerization of the GR is an integral step in glucocorticoid signaling and has been identified as a possible molecular site to target for drug development of anti-inflammatory drugs with an improved therapeutic index. Most of the current understanding regarding the role of GR dimerization in GC signaling derives for dimerization deficient mutants, although the role of ligands biased toward monomerization has also been described. Even though designing for loss of dimerization has mostly been applied for reduction of side-effect profile, designing for loss of dimerization may also be a fruitful strategy for the development of GC drugs with less potential to develop GC resistance. GC-induced resistance affects up to 30% of users and is due to a reduction in the GR functional pool. Several molecular mechanisms of GC-mediated reductions in GR pool have been described, one of which is the autologous down-regulation of GR density by the ubiquitin-proteasome-system (UPS). Loss of GR dimerization prevents autologous down-regulation of the receptor through modulation of interactions with components of the UPS and post-translational modifications (PTMs), such as phosphorylation, which prime the GR for degradation. Rational design of conformationally biased ligands that select for a monomeric GR conformation, which increases GC sensitivity through improving GR protein stability and increasing half-life, may be a productive avenue to explore. However, potential drawbacks to this approach should be considered as well as the advantages and disadvantages in chronic vs. acute treatment regimes.
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Affiliation(s)
- Ann Louw
- Department of Biochemistry, Stellenbosch University, Stellenbosch, South Africa
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