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Abdoul-Azize S, Hami R, Riou G, Derambure C, Charbonnier C, Vannier JP, Guzman ML, Schneider P, Boyer O. Glucocorticoids paradoxically promote steroid resistance in B cell acute lymphoblastic leukemia through CXCR4/PLC signaling. Nat Commun 2024; 15:4557. [PMID: 38811530 PMCID: PMC11136999 DOI: 10.1038/s41467-024-48818-9] [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: 02/15/2023] [Accepted: 05/15/2024] [Indexed: 05/31/2024] Open
Abstract
Glucocorticoid (GC) resistance in childhood relapsed B-cell acute lymphoblastic leukemia (B-ALL) represents an important challenge. Despite decades of clinical use, the mechanisms underlying resistance remain poorly understood. Here, we report that in B-ALL, GC paradoxically induce their own resistance by activating a phospholipase C (PLC)-mediated cell survival pathway through the chemokine receptor, CXCR4. We identify PLC as aberrantly activated in GC-resistant B-ALL and its inhibition is able to induce cell death by compromising several transcriptional programs. Mechanistically, dexamethasone (Dex) provokes CXCR4 signaling, resulting in the activation of PLC-dependent Ca2+ and protein kinase C signaling pathways, which curtail anticancer activity. Treatment with a CXCR4 antagonist or a PLC inhibitor improves survival of Dex-treated NSG mice in vivo. CXCR4/PLC axis inhibition significantly reverses Dex resistance in B-ALL cell lines (in vitro and in vivo) and cells from Dex resistant ALL patients. Our study identifies how activation of the PLC signalosome in B-ALL by Dex limits the upfront efficacy of this chemotherapeutic agent.
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Affiliation(s)
| | - Rihab Hami
- Univ Brest, Inserm, UMR 1101, F-29200, Brest, France
| | - Gaetan Riou
- Univ Rouen Normandie, Inserm, UMR 1234, F-76000, Rouen, France
| | | | | | | | - Monica L Guzman
- Division of Hematology and Oncology, Department of Medicine, Weill Cornell Medicine, New York, NY, USA
| | - Pascale Schneider
- Univ Rouen Normandie, Inserm, UMR 1234, F-76000, Rouen, France
- Rouen University Hospital, Department of Pediatric Immuno-Hemato-Oncology, F-76000, Rouen, France
| | - Olivier Boyer
- Univ Rouen Normandie, Inserm, UMR 1234, F-76000, Rouen, France
- Rouen University Hospital, Department of Immunology and Biotherapy, F-76000, Rouen, France
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2
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Viola MF, Chavero-Pieres M, Modave E, Delfini M, Stakenborg N, Estévez MC, Fabre N, Appeltans I, Martens T, Vandereyken K, Theobald H, Van Herck J, Petry P, Verheijden S, De Schepper S, Sifrim A, Liu Z, Ginhoux F, Azhar M, Schlitzer A, Matteoli G, Kierdorf K, Prinz M, Berghe PV, Voet T, Boeckxstaens G. Dedicated macrophages organize and maintain the enteric nervous system. Nature 2023:10.1038/s41586-023-06200-7. [PMID: 37316669 DOI: 10.1038/s41586-023-06200-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Accepted: 05/11/2023] [Indexed: 06/16/2023]
Abstract
Correct development and maturation of the enteric nervous system (ENS) is critical for survival1. At birth, the ENS is immature and requires considerable refinement to exert its functions in adulthood2. Here we demonstrate that resident macrophages of the muscularis externa (MMϕ) refine the ENS early in life by pruning synapses and phagocytosing enteric neurons. Depletion of MMϕ before weaning disrupts this process and results in abnormal intestinal transit. After weaning, MMϕ continue to interact closely with the ENS and acquire a neurosupportive phenotype. The latter is instructed by transforming growth factor-β produced by the ENS; depletion of the ENS and disruption of transforming growth factor-β signalling result in a decrease in neuron-associated MMϕ associated with loss of enteric neurons and altered intestinal transit. These findings introduce a new reciprocal cell-cell communication responsible for maintenance of the ENS and indicate that the ENS, similarly to the brain, is shaped and maintained by a dedicated population of resident macrophages that adapts its phenotype and transcriptome to the timely needs of the ENS niche.
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Affiliation(s)
- Maria Francesca Viola
- Laboratory for Intestinal Neuro-Immune Interaction, Translational Research Center for Gastrointestinal Disorders, Department of Chronic Diseases, Metabolism and Ageing, KU Leuven, Leuven, Belgium
| | - Marta Chavero-Pieres
- Laboratory for Intestinal Neuro-Immune Interaction, Translational Research Center for Gastrointestinal Disorders, Department of Chronic Diseases, Metabolism and Ageing, KU Leuven, Leuven, Belgium
| | - Elodie Modave
- Laboratory for Intestinal Neuro-Immune Interaction, Translational Research Center for Gastrointestinal Disorders, Department of Chronic Diseases, Metabolism and Ageing, KU Leuven, Leuven, Belgium
| | - Marcello Delfini
- Laboratory for Intestinal Neuro-Immune Interaction, Translational Research Center for Gastrointestinal Disorders, Department of Chronic Diseases, Metabolism and Ageing, KU Leuven, Leuven, Belgium
| | - Nathalie Stakenborg
- Laboratory for Intestinal Neuro-Immune Interaction, Translational Research Center for Gastrointestinal Disorders, Department of Chronic Diseases, Metabolism and Ageing, KU Leuven, Leuven, Belgium
| | - Maria Cuende Estévez
- Laboratory for Intestinal Neuro-Immune Interaction, Translational Research Center for Gastrointestinal Disorders, Department of Chronic Diseases, Metabolism and Ageing, KU Leuven, Leuven, Belgium
| | - Naomi Fabre
- Laboratory for Intestinal Neuro-Immune Interaction, Translational Research Center for Gastrointestinal Disorders, Department of Chronic Diseases, Metabolism and Ageing, KU Leuven, Leuven, Belgium
| | - Iris Appeltans
- Laboratory for Intestinal Neuro-Immune Interaction, Translational Research Center for Gastrointestinal Disorders, Department of Chronic Diseases, Metabolism and Ageing, KU Leuven, Leuven, Belgium
| | - Tobie Martens
- Laboratory for Enteric NeuroScience, Translational Research Center for Gastrointestinal Disorders, Department of Chronic Diseases, Metabolism and Ageing, KU Leuven, Leuven, Belgium
| | - Katy Vandereyken
- Laboratory of Reproductive Genomics, Department of Human Genetics, KU Leuven, Leuven, Belgium
- KU Leuven Institute for Single Cell Omics, KU Leuven, Leuven, Belgium
| | - Hannah Theobald
- Quantitative Systems Biology, LIMES-Institute, University of Bonn, Bonn, Germany
| | - Jens Van Herck
- Laboratory of Reproductive Genomics, Department of Human Genetics, KU Leuven, Leuven, Belgium
| | - Philippe Petry
- Institute of Neuropathology, Faculty of Medicine, University of Freiburg, Freiburg, Germany
- Faculty of Biology, University of Freiburg, Freiburg, Germany
| | - Simon Verheijden
- Laboratory for Intestinal Neuro-Immune Interaction, Translational Research Center for Gastrointestinal Disorders, Department of Chronic Diseases, Metabolism and Ageing, KU Leuven, Leuven, Belgium
- Janssen Research and Development, Janssen Pharmaceutica NV, Beerse, Belgium
| | - Sebastiaan De Schepper
- Laboratory for Intestinal Neuro-Immune Interaction, Translational Research Center for Gastrointestinal Disorders, Department of Chronic Diseases, Metabolism and Ageing, KU Leuven, Leuven, Belgium
- UK Dementia Research Institute, UCL Queen Square Institute of Neurology, Faculty of Brain Sciences, University College London, London, UK
| | - Alejandro Sifrim
- KU Leuven Institute for Single Cell Omics, KU Leuven, Leuven, Belgium
- Laboratory of Multi-Omic Integrative Bioinformatics, Department of Genetics, KU Leuven, Leuven, Belgium
- Leuven AI Institute, KU Leuven, Leuven, Belgium
| | - Zhaoyuan Liu
- Shanghai Institute of Immunology, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Florent Ginhoux
- Shanghai Institute of Immunology, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Singapore Immunology Network, Agency for Science, Technology & Research, Singapore, Singapore
- Translational Immunology Institute, SingHealth Duke-NUS Academic Medical Centre, Singapore, Singapore
| | - Mohamad Azhar
- Department of Cell Biology and Anatomy, University of South Carolina School of Medicine, Columbia, SC, USA
| | - Andreas Schlitzer
- Quantitative Systems Biology, LIMES-Institute, University of Bonn, Bonn, Germany
| | - Gianluca Matteoli
- Laboratory for Mucosal Immunology, Translational Research Center for Gastrointestinal Disorders, Department of Chronic Diseases, Metabolism and Ageing, KU Leuven, Leuven, Belgium
| | - Katrin Kierdorf
- Institute of Neuropathology, Faculty of Medicine, University of Freiburg, Freiburg, Germany
- Centre for Integrative Biological Signalling Studies, University of Freiburg, Freiburg, Germany
- Center for Basics in NeuroModulation (NeuroModulBasics), Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Marco Prinz
- Institute of Neuropathology, Faculty of Medicine, University of Freiburg, Freiburg, Germany
- Center for Basics in NeuroModulation (NeuroModulBasics), Faculty of Medicine, University of Freiburg, Freiburg, Germany
- Faculty of Medicine, University of Freiburg, Freiburg, Germany
- Signalling Research Centres BIOSS and CIBSS, University of Freiburg, Freiburg, Germany
| | - Pieter Vanden Berghe
- Laboratory for Enteric NeuroScience, Translational Research Center for Gastrointestinal Disorders, Department of Chronic Diseases, Metabolism and Ageing, KU Leuven, Leuven, Belgium
| | - Thierry Voet
- Laboratory of Reproductive Genomics, Department of Human Genetics, KU Leuven, Leuven, Belgium
- KU Leuven Institute for Single Cell Omics, KU Leuven, Leuven, Belgium
| | - Guy Boeckxstaens
- Laboratory for Intestinal Neuro-Immune Interaction, Translational Research Center for Gastrointestinal Disorders, Department of Chronic Diseases, Metabolism and Ageing, KU Leuven, Leuven, Belgium.
- KU Leuven Institute for Single Cell Omics, KU Leuven, Leuven, Belgium.
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Li W, Yuan J. Targeting RIPK1 kinase for modulating inflammation in human diseases. Front Immunol 2023; 14:1159743. [PMID: 36969188 PMCID: PMC10030951 DOI: 10.3389/fimmu.2023.1159743] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Accepted: 02/27/2023] [Indexed: 03/29/2023] Open
Abstract
Receptor-Interacting Serine/Threonine-Protein Kinase 1 (RIPK1) is a master regulator of TNFR1 signaling in controlling cell death and survival. While the scaffold of RIPK1 participates in the canonical NF-κB pathway, the activation of RIPK1 kinase promotes not only necroptosis and apoptosis, but also inflammation by mediating the transcriptional induction of inflammatory cytokines. The nuclear translocation of activated RIPK1 has been shown to interact BAF-complex to promote chromatin remodeling and transcription. This review will highlight the proinflammatory role of RIPK1 kinase with focus on human neurodegenerative diseases. We will discuss the possibility of targeting RIPK1 kinase for the treatment of inflammatory pathology in human diseases.
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Affiliation(s)
- Wanjin Li
- *Correspondence: Wanjin Li, ; Junying Yuan,
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4
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Pal P, Atilla-Gokcumen GE, Frasor J. Emerging Roles of Ceramides in Breast Cancer Biology and Therapy. Int J Mol Sci 2022; 23:ijms231911178. [PMID: 36232480 PMCID: PMC9569866 DOI: 10.3390/ijms231911178] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 09/15/2022] [Accepted: 09/20/2022] [Indexed: 11/16/2022] Open
Abstract
One of the classic hallmarks of cancer is the imbalance between elevated cell proliferation and reduced cell death. Ceramide, a bioactive sphingolipid that can regulate this balance, has long been implicated in cancer. While the effects of ceramide on cell death and therapeutic efficacy are well established, emerging evidence indicates that ceramide turnover to downstream sphingolipids, such as sphingomyelin, hexosylceramides, sphingosine-1-phosphate, and ceramide-1-phosphate, is equally important in driving pro-tumorigenic phenotypes, such as proliferation, survival, migration, stemness, and therapy resistance. The complex and dynamic sphingolipid network has been extensively studied in several cancers, including breast cancer, to find key sphingolipidomic alterations that can be exploited to develop new therapeutic strategies to improve patient outcomes. Here, we review how the current literature shapes our understanding of how ceramide synthesis and turnover are altered in breast cancer and how these changes offer potential strategies to improve breast cancer therapy.
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Affiliation(s)
- Purab Pal
- Department of Physiology and Biophysics, College of Medicine, University of Illinois at Chicago, Chicago, IL 60612, USA
| | - G. Ekin Atilla-Gokcumen
- Department of Chemistry, University at Buffalo, The State University of New York (SUNY), Buffalo, NY 14260, USA
- Correspondence: (G.E.A.-G.); (J.F.)
| | - Jonna Frasor
- Department of Physiology and Biophysics, College of Medicine, University of Illinois at Chicago, Chicago, IL 60612, USA
- Correspondence: (G.E.A.-G.); (J.F.)
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5
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Witas R, Shen Y, Nguyen CQ. Bone marrow-derived macrophages from a murine model of Sjögren's syndrome demonstrate an aberrant, inflammatory response to apoptotic cells. Sci Rep 2022; 12:8593. [PMID: 35597820 PMCID: PMC9124194 DOI: 10.1038/s41598-022-12608-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Accepted: 05/05/2022] [Indexed: 11/30/2022] Open
Abstract
Sjögren's syndrome (SjS) is a female-dominated autoimmune disease involving lymphocytic infiltration of the exocrine glands. We have previously demonstrated cleavage of the TAM (Tyro3, Axl, Mer) receptor Mer is enhanced in SjS, leading to defective efferocytosis. Mer also plays a role in modulating phagocyte inflammatory response to apoptotic cells. Here we investigated the SjS macrophage response to apoptotic cells (AC). Bone marrow-derived macrophages (BMDMs) from SjS-susceptible (SjSs) C57BL/6.NOD-Aec1Aec2 mice and C57BL/6 (B6) controls were treated with either AC or CpG-oligodeoxynucleotides. RNA was collected from macrophages and bulk sequencing was performed to analyze transcripts. Cytokine expression was confirmed by Bio-plex. RT-qPCR was used to determine toll-like receptor (TLR) 7 and 9 involvement in BMDM inflammatory response to apoptotic cells. SjSS BMDMs exhibited a distinct transcriptional profile involving upregulation of a broad array of inflammatory genes that were not elevated in B6 BMDMs by AC. Inhibition of TLR 7 and 9 was found to limit the inflammatory response of SjSS BMDMs to ACs. ACs elicit an inflammatory reaction in SjSS BMDMs distinct from that observed in B6 BMDMs. This discovery of aberrant macrophage behavior in SjS in conjunction with previously described efferocytosis defects suggests an expanded role for macrophages in SjS, where uncleared dead cells stimulate an inflammatory response through macrophage TLRs recruiting lymphocytes, participating in co-stimulation and establishing an environment conducive to autoimmunity.
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Affiliation(s)
- Richard Witas
- Department of Infectious Diseases and Immunology, College of Veterinary Medicine, University of Florida, PO Box 110880, Gainesville, FL, 32611-0880, USA.,Department of Oral Biology, College of Dentistry, University of Florida, Gainesville, FL, USA
| | - Yiran Shen
- Department of Infectious Diseases and Immunology, College of Veterinary Medicine, University of Florida, PO Box 110880, Gainesville, FL, 32611-0880, USA
| | - Cuong Q Nguyen
- Department of Infectious Diseases and Immunology, College of Veterinary Medicine, University of Florida, PO Box 110880, Gainesville, FL, 32611-0880, USA. .,Department of Oral Biology, College of Dentistry, University of Florida, Gainesville, FL, USA. .,Center of Orphaned Autoimmune Diseases, University of Florida, Gainesville, FL, USA.
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6
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Dacic M, Shibu G, Rogatsky I. Physiological Convergence and Antagonism Between GR and PPARγ in Inflammation and Metabolism. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2022; 1390:123-141. [PMID: 36107316 DOI: 10.1007/978-3-031-11836-4_7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Nuclear receptors (NRs) are transcription factors that modulate gene expression in a ligand-dependent manner. The ubiquitously expressed glucocorticoid receptor (GR) and peroxisome proliferator-activated receptor gamma (PPARγ) represent steroid (type I) and non-steroid (type II) classes of NRs, respectively. The diverse transcriptional and physiological outcomes of their activation are highly tissue-specific. For example, in subsets of immune cells, such as macrophages, the signaling of GR and PPARγ converges to elicit an anti-inflammatory phenotype; in contrast, in the adipose tissue, their signaling can lead to reciprocal metabolic outcomes. This review explores the cooperative and divergent outcomes of GR and PPARγ functions in different cell types and tissues, including immune cells, adipose tissue and the liver. Understanding the coordinated control of these NR pathways should advance studies in the field and potentially pave the way for developing new therapeutic approaches to exploit the GR:PPARγ crosstalk.
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Affiliation(s)
- 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
| | - Gayathri Shibu
- 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
| | - 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.
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7
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Bruscoli S, Riccardi C, Ronchetti S. GILZ as a Regulator of Cell Fate and Inflammation. Cells 2021; 11:cells11010122. [PMID: 35011684 PMCID: PMC8750894 DOI: 10.3390/cells11010122] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Revised: 12/21/2021] [Accepted: 12/29/2021] [Indexed: 12/30/2022] Open
Abstract
One of the human body’s initial responses to stress is the adrenal response, involving the release of mediators that include adrenaline and glucocorticoids (GC). GC are involved in controlling the inflammatory and immune response mechanisms. Of these, the molecular mechanisms that contribute to anti-inflammatory effects warrant more investigation. Previously, we found that GC induced GILZ (glucocorticoid-induced leucine zipper) quickly and widely in thymocytes, T lymphocytes, and other leukocytes. GILZ regulates the activation of cells and is an essential mediator of endogenous GC and the majority of GC anti-inflammatory effects. Further research in this regard could lead to the development of an anti-inflammatory treatment that yields the therapeutic outcomes of GC but without their characteristic adverse effects. Here, we examine the mechanisms of GILZ in the context of GC. Specifically, we review its role in the proliferation and differentiation of cells and in apoptosis. We also examine its involvement in immune cells (macrophages, neutrophils, dendritic cells, T and B lymphocytes), and in non-immune cells, including cancer cells. In conclusion, GILZ is an anti-inflammatory molecule that could mediate the immunomodulatory activities of GC, with less adverse effects, and could be a target molecule for designing new therapies to treat inflammatory diseases.
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Kinsella S, Evandy CA, Cooper K, Iovino L, deRoos PC, Hopwo KS, Granadier DW, Smith CW, Rafii S, Dudakov JA. Attenuation of apoptotic cell detection triggers thymic regeneration after damage. Cell Rep 2021; 37:109789. [PMID: 34610317 PMCID: PMC8627669 DOI: 10.1016/j.celrep.2021.109789] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 07/02/2021] [Accepted: 09/10/2021] [Indexed: 01/21/2023] Open
Abstract
The thymus, which is the primary site of T cell development, is particularly sensitive to insult but also has a remarkable capacity for repair. However, the mechanisms orchestrating regeneration are poorly understood, and delayed repair is common after cytoreductive therapies. Here, we demonstrate a trigger of thymic regeneration, centered on detecting the loss of dying thymocytes that are abundant during steady-state T cell development. Specifically, apoptotic thymocytes suppressed production of the regenerative factors IL-23 and BMP4 via TAM receptor signaling and activation of the Rho-GTPase Rac1, the intracellular pattern recognition receptor NOD2, and micro-RNA-29c. However, after damage, when profound thymocyte depletion occurs, this TAM-Rac1-NOD2-miR29c pathway is attenuated, increasing production of IL-23 and BMP4. Notably, pharmacological inhibition of Rac1-GTPase enhanced thymic function after acute damage. These findings identify a complex trigger of tissue regeneration and offer a regenerative strategy for restoring immune competence in patients whose thymic function has been compromised.
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Affiliation(s)
- Sinéad Kinsella
- Program in Immunology, Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA; Immunotherapy Integrated Research Center, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA.
| | - Cindy A Evandy
- Program in Immunology, Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA; Immunotherapy Integrated Research Center, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
| | - Kirsten Cooper
- Program in Immunology, Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA; Immunotherapy Integrated Research Center, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
| | - Lorenzo Iovino
- Program in Immunology, Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA; Immunotherapy Integrated Research Center, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
| | - Paul C deRoos
- Program in Immunology, Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA; Immunotherapy Integrated Research Center, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
| | - Kayla S Hopwo
- Program in Immunology, Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA; Immunotherapy Integrated Research Center, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
| | - David W Granadier
- Program in Immunology, Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA; Immunotherapy Integrated Research Center, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
| | - Colton W Smith
- Program in Immunology, Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA; Immunotherapy Integrated Research Center, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
| | - Shahin Rafii
- Department of Genetic Medicine and Ansary Stem Cell Institute, Weill Cornell Medical College, New York, NY 10021, USA
| | - Jarrod A Dudakov
- Program in Immunology, Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA; Immunotherapy Integrated Research Center, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA; Department of Immunology, University of Washington, Seattle, WA 98109, USA.
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9
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Pontejo SM, Murphy PM. Chemokines act as phosphatidylserine-bound "find-me" signals in apoptotic cell clearance. PLoS Biol 2021; 19:e3001259. [PMID: 34038417 PMCID: PMC8213124 DOI: 10.1371/journal.pbio.3001259] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Revised: 06/18/2021] [Accepted: 05/05/2021] [Indexed: 12/14/2022] Open
Abstract
Removal of apoptotic cells is essential for maintenance of tissue homeostasis. Chemotactic cues termed "find-me" signals attract phagocytes toward apoptotic cells, which selectively expose the anionic phospholipid phosphatidylserine (PS) and other "eat-me" signals to distinguish healthy from apoptotic cells for phagocytosis. Blebs released by apoptotic cells can deliver find-me signals; however, the mechanism is poorly understood. Here, we demonstrate that apoptotic blebs generated in vivo from mouse thymus attract phagocytes using endogenous chemokines bound to the bleb surface. We show that chemokine binding to apoptotic cells is mediated by PS and that high affinity binding of PS and other anionic phospholipids is a general property of many but not all chemokines. Chemokines are positively charged proteins that also bind to anionic glycosaminoglycans (GAGs) on cell surfaces for presentation to leukocyte G protein-coupled receptors (GPCRs). We found that apoptotic cells down-regulate GAGs as they up-regulate PS on the cell surface and that PS-bound chemokines, unlike GAG-bound chemokines, are able to directly activate chemokine receptors. Thus, we conclude that PS-bound chemokines may serve as find-me signals on apoptotic vesicles acting at cognate chemokine receptors on leukocytes.
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Affiliation(s)
- Sergio M Pontejo
- Molecular Signaling Section, Laboratory of Molecular Immunology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Philip M Murphy
- Molecular Signaling Section, Laboratory of Molecular Immunology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
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Comparison of Hearing Preservation Outcomes Using Extended Versus Single-Dose Steroid Therapy in Cochlear Implantation. Otol Neurotol 2021; 41:e449-e457. [PMID: 32176129 DOI: 10.1097/mao.0000000000002570] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
OBJECTIVES The purpose of this study was to compare the hearing preservation outcomes of patients who received extended versus single-dose steroid therapy in cochlear implant surgery. DESIGN Case-control. SETTING Tertiary referral centers in Taiwan from April 2017 to 2019. PARTICIPANTS A total of 70 patients aged 1 to 78 years old (mean = 18.04, standard deviation [SD] = 21.51) who received cochlear implantation via the round window approach were included in the study. Prospectively, 35 cases were enrolled for cochlear implantation with single-dose therapy. Thirty-five controls who underwent cochlear implantation with extended therapy were retrospectively enrolled after frequency matching. OUTCOME MEASURES The main outcome measure was the rate of hearing preservation. This was calculated based on the HEARRING Network formula and results were categorized as complete, partial, and minimal. Impedances served as secondary outcomes. RESULTS There was no significant difference in the complete hearing preservation rates between the extended and single-dose groups at 6 months postoperatively. Impedances were significantly lower in the extended group after 1 month and 6 months of follow up. When the complete and partial hearing preservation groups were compared, the size of round window opening and speed of insertion were found to be statistically significant. CONCLUSIONS Both extended and single-dose therapies result in good hearing preservation in patients who undergo cochlear implantation. However, better impedances can be expected from patients who received extended therapy. A slower speed of insertion and a widely opened round window play a role in hearing preservation.
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11
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Field BC, Gordillo R, Scherer PE. The Role of Ceramides in Diabetes and Cardiovascular Disease Regulation of Ceramides by Adipokines. Front Endocrinol (Lausanne) 2020; 11:569250. [PMID: 33133017 PMCID: PMC7564167 DOI: 10.3389/fendo.2020.569250] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Accepted: 09/09/2020] [Indexed: 12/12/2022] Open
Abstract
Metabolic dysfunction is intertwined with the pathophysiology of both diabetes and cardiovascular disease. Recently, one particular lipid class has been shown to influence the development and sustainment of these diseases: ceramides. As a subtype of sphingolipids, these species are particularly central to many sphingolipid pathways. Increased levels of ceramides are known to correlate with impaired cardiovascular and metabolic health. Furthermore, the interaction between ceramides and adipokines, most notably adiponectin and leptin, appears to play a role in the pathophysiology of these conditions. Adiponectin appears to counteract the detrimental effects of elevated ceramides, largely through activation of the ceramidase activity of its receptors. Elevated ceramides appear to worsen leptin resistance, which is an important phenomenon in the pathophysiology of obesity and metabolic syndrome.
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Affiliation(s)
- Bianca C. Field
- Touchstone Diabetes Center, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - Ruth Gordillo
- Touchstone Diabetes Center, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - Philipp E. Scherer
- Touchstone Diabetes Center, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, United States
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, United States
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12
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Clarisse D, Offner F, De Bosscher K. Latest perspectives on glucocorticoid-induced apoptosis and resistance in lymphoid malignancies. Biochim Biophys Acta Rev Cancer 2020; 1874:188430. [PMID: 32950642 DOI: 10.1016/j.bbcan.2020.188430] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Revised: 08/13/2020] [Accepted: 09/14/2020] [Indexed: 02/09/2023]
Abstract
Glucocorticoids are essential drugs in the treatment protocols of lymphoid malignancies. These steroidal hormones trigger apoptosis of the malignant cells by binding to the glucocorticoid receptor (GR), which is a member of the nuclear receptor superfamily. Long term glucocorticoid treatment is limited by two major problems: the development of glucocorticoid-related side effects, which hampers patient quality of life, and the emergence of glucocorticoid resistance, which is a gradual process that is inevitable in many patients. This emphasizes the need to reevaluate and optimize the widespread use of glucocorticoids in lymphoid malignancies. To achieve this goal, a deep understanding of the mechanisms governing glucocorticoid responsiveness is required, yet, a recent comprehensive overview is currently lacking. In this review, we examine how glucocorticoids mediate apoptosis by detailing GR's genomic and non-genomic action mechanisms in lymphoid malignancies. We continue with a discussion of the glucocorticoid-related problems and how these are intertwined with one another. We further zoom in on glucocorticoid resistance by critically analyzing the plethora of proposed mechanisms and highlighting therapeutic opportunities that emerge from these studies. In conclusion, early detection of glucocorticoid resistance in patients remains an important challenge as this would result in a timelier treatment reorientation and reduced glucocorticoid-instigated side effects.
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Affiliation(s)
- Dorien Clarisse
- Translational Nuclear Receptor Research, VIB-UGent Center for Medical Biotechnology, Ghent, Belgium; Department of Biomolecular Medicine, Ghent University, Ghent, Belgium; Cancer Research Institute Ghent (CRIG), Ghent, Belgium.
| | - Fritz Offner
- Cancer Research Institute Ghent (CRIG), Ghent, Belgium; Department of Internal Medicine and Pediatrics, Ghent University Hospital, Ghent, Belgium
| | - Karolien De Bosscher
- Translational Nuclear Receptor Research, VIB-UGent Center for Medical Biotechnology, Ghent, Belgium; Department of Biomolecular Medicine, Ghent University, Ghent, Belgium; Cancer Research Institute Ghent (CRIG), Ghent, Belgium.
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13
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Maggioncalda EC, Story-Roller E, Mylius J, Illei P, Basaraba RJ, Lamichhane G. A mouse model of pulmonary Mycobacteroides abscessus infection. Sci Rep 2020; 10:3690. [PMID: 32111900 PMCID: PMC7048719 DOI: 10.1038/s41598-020-60452-1] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Accepted: 02/12/2020] [Indexed: 02/01/2023] Open
Abstract
There is no preclinical mouse model to investigate pulmonary Mycobacteroides abscessus (formerly Mycobacterium abscessus) infection in an immunocompetent mouse strain, especially in the context of antibiotic testing and regimen development. We developed a mouse model of pulmonary M. abscessus infection using the aerosolized route of infection that leads to an increase in bacterial burden post- implantation and develops pathology as a result. In this mouse model, treatment with corticosteroid allows for initial proliferation and sustained M. abscessus pulmonary infection and permits evaluation of efficacies of antibiotics. Administration of corticosteroids that permitted higher levels of bacterial burden in the lungs were more likely to have pathology. Treatment of mice with antibiotics administered intranasally or subcutaneously significantly reduced lung M. abscessus burden. In addition to the reference strain, independent clinical isolates of M. abscessus also readily establish infection and proliferate in the lungs of mice in this model.
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Affiliation(s)
- Emily C Maggioncalda
- Division of Infectious Diseases, School of Medicine, Johns Hopkins University, Baltimore, MD, 21287, USA
| | - Elizabeth Story-Roller
- Division of Infectious Diseases, School of Medicine, Johns Hopkins University, Baltimore, MD, 21287, USA
| | - Julian Mylius
- Department of Microbiology, Immunology, and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO, 80523, USA
| | - Peter Illei
- The Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA.,Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Randall J Basaraba
- Department of Microbiology, Immunology, and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO, 80523, USA
| | - Gyanu Lamichhane
- Division of Infectious Diseases, School of Medicine, Johns Hopkins University, Baltimore, MD, 21287, USA.
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14
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Mücke VT, Thomas D, Mücke MM, Waidmann O, Zeuzem S, Sarrazin C, Pfeilschifter J, Vermehren J, Finkelmeier F, Grammatikos G. Serum sphingolipids predict de novo hepatocellular carcinoma in hepatitis C cirrhotic patients with sustained virologic response. Liver Int 2019; 39:2174-2183. [PMID: 31207039 DOI: 10.1111/liv.14178] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Revised: 05/28/2019] [Accepted: 06/08/2019] [Indexed: 12/13/2022]
Abstract
BACKGROUND & AIMS Curing hepatitis C virus (HCV) infection reduces the risk of hepatocellular carcinoma (HCC) development, yet HCC occurs despite sustained virologic response (SVR) in 2%-8% of cirrhotic patients. Sphingolipids (SLs) have been identified as new biomarkers of chronic liver disease and HCC. The aim of this study was to evaluate serum SLs as diagnostic HCC biomarkers in patients with HCV-associated cirrhosis at SVR12. METHODS From 2014 to 2016, 166 patients with HCV-cirrhosis and SVR were recruited and SL profiles were measured at baseline and 12 weeks after completion of direct-acting antiviral (DAA) therapy. All patients received HCC surveillance in line with current guideline recommendations. Minimum follow-up period comprised 6 months. RESULTS Our study included 130 (78%) patients without history of HCC, 25 (15%) with history of HCC prior DAA therapy and 11 (7%) patients with de novo HCC after FU12. In those with upcoming de novo HCC serum C24DHC (P = 0.006), C24:1DHC (P = 0.048) and C16Cer (P = 0.011) were significantly upregulated at FU12, but not AFP (P = 0.138). Contemporaneous ultrasound did not visualize HCC, at this time. C16Cer stayed sole independent predictor with high diagnostic accuracy of AFP-positive (AUC = 0.741) and -negative (AUC = 0.766) HCC development. Serum SL parameters decreased from baseline to SVR12. CONCLUSIONS C24DHC, C24:1DHC and especially C16Cer were superior to AFP in early detection of AFP-positive and -negative de novo HCC development. We observed significant SL profile changes upon SVR. SLs may play a role in non-invasive HCC surveillance and hepatocarcinogenesis.
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Affiliation(s)
| | - Dominique Thomas
- Pharmazentrum Frankfurt, Institut für Klinische Pharmakologie, Frankfurt am Main, Germany
| | - Marcus M Mücke
- Universitätsklinikum Frankfurt, Frankfurt am Main, Germany
| | | | - Stefan Zeuzem
- Universitätsklinikum Frankfurt, Frankfurt am Main, Germany
| | - Christoph Sarrazin
- Universitätsklinikum Frankfurt, Frankfurt am Main, Germany.,St. Josefs-Hospital, Wiesbaden, Germany
| | - Josef Pfeilschifter
- Pharmazentrum Frankfurt, Institut für Allgemeine Pharmakologie und Toxikologie, Frankfurt am Main, Germany
| | | | | | - Georgios Grammatikos
- Universitätsklinikum Frankfurt, Frankfurt am Main, Germany.,St. Luke's Hospital Thessaloniki, Panorama, Greece
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15
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Defining the role of glucocorticoids in inflammation. Clin Sci (Lond) 2018; 132:1529-1543. [DOI: 10.1042/cs20171505] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Revised: 06/14/2018] [Accepted: 07/09/2018] [Indexed: 12/20/2022]
Abstract
An established body of knowledge and clinical practice has argued in favor of the use of glucocorticoids in various chronic inflammatory and autoimmune diseases. However, the very well-known adverse effects associated with their treatment hampers continuation of therapy with glucocorticoids. Analyses of the molecular mechanisms underlying the actions of glucocorticoids have led to the discovery of several mediators that add complexity and diversity to the puzzling world of these hormones and anti-inflammatory drugs. Such mediators hold great promise as alternative pharmacologic tools to be used as anti-inflammatory drugs with the same properties as glucocorticoids, but avoiding their metabolic side effects. This review summarizes findings about the molecular targets and mediators of glucocorticoid function.
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16
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Bereshchenko O, Bruscoli S, Riccardi C. Glucocorticoids, Sex Hormones, and Immunity. Front Immunol 2018; 9:1332. [PMID: 29946321 PMCID: PMC6006719 DOI: 10.3389/fimmu.2018.01332] [Citation(s) in RCA: 153] [Impact Index Per Article: 25.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2018] [Accepted: 05/29/2018] [Indexed: 12/15/2022] Open
Abstract
Glucocorticoid hormones regulate essential body functions in mammals, control cell metabolism, growth, differentiation, and apoptosis. Importantly, they are potent suppressors of inflammation, and multiple immune-modulatory mechanisms involving leukocyte apoptosis, differentiation, and cytokine production have been described. Due to their potent anti-inflammatory and immune-suppressive activity, synthetic glucocorticoids (GCs) are the most prescribed drugs used for treatment of autoimmune and inflammatory diseases. It is long been noted that males and females exhibit differences in the prevalence in several autoimmune diseases (AD). This can be due to the role of sexual hormones in regulation of the immune responses, acting through their endogenous nuclear receptors to mediate gene expression and generate unique gender-specific cellular environments. Given the fact that GCs are the primary physiological anti-inflammatory hormones, and that sex hormones may also exert immune-modulatory functions, the link between GCs and sex hormones may exist. Understanding the nature of this possible crosstalk is important to unravel the reason of sexual disparity in AD and to carefully prescribe these drugs for the treatment of inflammatory diseases. In this review, we discuss similarities and differences between the effects of sex hormones and GCs on the immune system, to highlight possible axes of functional interaction.
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Affiliation(s)
- Oxana Bereshchenko
- Section of Pharmacology, Department of Medicine, University of Perugia, Perugia, Italy.,Department of Surgery and Biomedical Sciences, University of Perugia, Perugia, Italy
| | - Stefano Bruscoli
- Section of Pharmacology, Department of Medicine, University of Perugia, Perugia, Italy
| | - Carlo Riccardi
- Section of Pharmacology, Department of Medicine, University of Perugia, Perugia, Italy
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17
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Abstract
Currently, over 10% of the US population is taking antidepressants. Numerous antidepressants such as amitriptyline are known to inhibit acid sphingomyelinase (Asm), an enzyme that is known to mediate leukocyte function and homeostasis. Severe burn injury can lead to an immunosuppressive state that is characterized by decreased leukocyte function and numbers as well as increased susceptibility to infection. Based upon the intersection of these facts, we hypothesized that amitriptyline-treated, scald-injured mice would have an altered immune response to injury as compared with untreated scald mice. Prior to burn, mice were pretreated with amitriptyline. Drug- or saline-treated mice were subjected full thickness dorsal scald- or sham-injury. Immune cells from spleen, thymus, and bone marrow were subsequently harvested and characterized. We first observed that amitriptyline prior to burn injury increased body mass loss and spleen contraction. Both amitriptylinetreatment and burn injury resulted in a 40% decrease of leukocyte Asm activity. Following scald injury, we demonstrate increased reduction of lymphocyte precursors in the bone marrow and thymus, as well as mature leukocytes in the spleen in mice that were treated with amitriptyline. We also demonstrate that amitriptyline treatment prior to injury reduced neutrophil accumulation following peptidoglycan stimulus in scald-injured mice. These data show that Asm alterations can play a significant role in mediating alterations to the immune system after injury. The data further suggest that those taking antidepressants may be at a higher risk for complications following burn injury.
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18
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Karatzanis A, Chatzidakis A, Milioni A, Vlaminck S, Kawauchi H, Velegrakis S, Prokopakis E. Contemporary Use of Corticosteroids in Rhinology. Curr Allergy Asthma Rep 2017; 17:11. [PMID: 28233155 DOI: 10.1007/s11882-017-0679-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
PURPOSE OF REVIEW Exogenously administered corticosteroids are widely used today in the field of rhinology. Allergic rhinitis (AR), non-allergic rhinitis (NAR), acute rhinosinusitis (ARS), chronic rhinosinusitis with (CRSwNP) and without (CRSsNP) nasal polyps, and autoimmune disorders with nasal manifestations are common diseases treated effectively with intranasal and oral glucocorticoids. We focus on physiological pathways, therapeutic benefits, indications, contra-indications, and side effects of glucocorticoid utilization in the treatment of rhinologic disorders such as AR, NAR, ARS, CRSsNP, and CRSwNP. RECENT FINDINGS Second-generation intranasal steroid (INS) agents have pharmacokinetic characteristics that minimize their systemic bioavailability, resulting in minimum risk for systemic adverse events. Several studies have demonstrated the symptomatic efficacy of both intranasal and oral corticosteroids in ARS. Moreover, intranasal and systemic steroid administration has been repeatedly proven beneficial in the conservative and perioperative management of CRSwNP. For patients with AR, there is no need for oral steroids, with the exception of severe cases, as there is lack of superiority to INS. SCUAD patients challenge currently available treatment schemes, underlining the importance of research in the field. Corticosteroids' effectiveness in the treatment of various rhinologic disorders is indisputable. However, their characteristics, and potential side effects, make a clear consensus for utilization difficult.
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Affiliation(s)
- Alexander Karatzanis
- Department of Otorhinolaryngology, School of Medicine, University of Crete, Heraklion, Crete, Greece
| | - Alkiviadis Chatzidakis
- Department of Otorhinolaryngology, School of Medicine, University of Crete, Heraklion, Crete, Greece
| | - Athanasia Milioni
- Department of Otorhinolaryngology, School of Medicine, University of Crete, Heraklion, Crete, Greece
| | - Stephan Vlaminck
- Department of Otorhinolaryngology, St. Jan General Hospital, Bruges, Belgium
| | - Hideyuki Kawauchi
- Department of Otorhinolaryngology, School of Medicine, University of Shimane, Shimane, Japan
| | - Stylianos Velegrakis
- Department of Otorhinolaryngology, School of Medicine, University of Crete, Heraklion, Crete, Greece
| | - Emmanuel Prokopakis
- Department of Otorhinolaryngology, School of Medicine, University of Crete, Heraklion, Crete, Greece. .,Department of Otorhinolaryngology, University Hospital of Crete, University avenue, A Building 3rd Floor, 71110, Heraklion, Crete, Greece.
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19
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Kilbey A, Terry A, Wotton S, Borland G, Zhang Q, Mackay N, McDonald A, Bell M, Wakelam MJO, Cameron ER, Neil JC. Runx1 Orchestrates Sphingolipid Metabolism and Glucocorticoid Resistance in Lymphomagenesis. J Cell Biochem 2017; 118:1432-1441. [PMID: 27869314 PMCID: PMC5408393 DOI: 10.1002/jcb.25802] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2016] [Accepted: 11/18/2016] [Indexed: 12/12/2022]
Abstract
The three‐membered RUNX gene family includes RUNX1, a major mutational target in human leukemias, and displays hallmarks of both tumor suppressors and oncogenes. In mouse models, the Runx genes appear to act as conditional oncogenes, as ectopic expression is growth suppressive in normal cells but drives lymphoma development potently when combined with over‐expressed Myc or loss of p53. Clues to underlying mechanisms emerged previously from murine fibroblasts where ectopic expression of any of the Runx genes promotes survival through direct and indirect regulation of key enzymes in sphingolipid metabolism associated with a shift in the “sphingolipid rheostat” from ceramide to sphingosine‐1‐phosphate (S1P). Testing of this relationship in lymphoma cells was therefore a high priority. We find that ectopic expression of Runx1 in lymphoma cells consistently perturbs the sphingolipid rheostat, whereas an essential physiological role for Runx1 is revealed by reduced S1P levels in normal spleen after partial Cre‐mediated excision. Furthermore, we show that ectopic Runx1 expression confers increased resistance of lymphoma cells to glucocorticoid‐mediated apoptosis, and elucidate the mechanism of cross‐talk between glucocorticoid and sphingolipid metabolism through Sgpp1. Dexamethasone potently induces expression of Sgpp1 in T‐lymphoma cells and drives cell death which is reduced by partial knockdown of Sgpp1 with shRNA or direct transcriptional repression of Sgpp1 by ectopic Runx1. Together these data show that Runx1 plays a role in regulating the sphingolipid rheostat in normal development and that perturbation of this cell fate regulator contributes to Runx‐driven lymphomagenesis. J. Cell. Biochem. 118: 1432–1441, 2017. © 2016 The Authors. Journal of Cellular Biochemistry Published by Wiley Periodicals, Inc.
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Affiliation(s)
- A Kilbey
- Molecular Oncology Laboratory, Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, G61 1QH, United Kingdom
| | - A Terry
- Molecular Oncology Laboratory, Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, G61 1QH, United Kingdom
| | - S Wotton
- Molecular Oncology Laboratory, Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, G61 1QH, United Kingdom
| | - G Borland
- Molecular Oncology Laboratory, Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, G61 1QH, United Kingdom
| | - Q Zhang
- The Babraham Institute, Babraham Research Campus, Cambridge, CB22 3AT, Cambridgeshire, United Kingdom
| | - N Mackay
- Molecular Oncology Laboratory, Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, G61 1QH, United Kingdom
| | - A McDonald
- Molecular Oncology Laboratory, Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, G61 1QH, United Kingdom
| | - M Bell
- Molecular Oncology Laboratory, Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, G61 1QH, United Kingdom
| | - M J O Wakelam
- The Babraham Institute, Babraham Research Campus, Cambridge, CB22 3AT, Cambridgeshire, United Kingdom
| | - E R Cameron
- Molecular Oncology Laboratory, Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, G61 1QH, United Kingdom
| | - J C Neil
- Molecular Oncology Laboratory, Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, G61 1QH, United Kingdom
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20
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Chen YL, Chen YT, Lo CF, Hsieh CI, Chiu SY, Wu CY, Yeh YS, Hung SH, Cheng PH, Su YH, Jiang ST, Chin HJ, Su YC. Early Detection of T cell Transfer-induced Autoimmune Colitis by In Vivo Imaging System. Sci Rep 2016; 6:35635. [PMID: 27762297 PMCID: PMC5071899 DOI: 10.1038/srep35635] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2016] [Accepted: 10/03/2016] [Indexed: 12/15/2022] Open
Abstract
Inflammatory bowel disease is a chronic and progressive inflammatory intestinal disease that includes two major types, namely ulcerative colitis and Crohn’s disease (CD). CD is characterized by intestinal epithelial hyperplasia and inflammatory cell infiltration. Transfer of CD25−CD45RBhiCD4+ (naïve) T cells into immunodeficiency mice induces autoimmune colitis with pathological lesions similar to CD and loss of body weight 4 weeks after cell transfer. However, weight loss neither has sufficient sensitivity nor totally matches the pathological findings of CD. To establish an early and sensitive indicator of autoimmune colitis model, the transferred T cell-induced colitis mouse model was modified by transferring luciferase-expressing donor T cells and determining the colitis by in vivo imaging system (IVIS). Colitis was detected with IVIS 7–10 days before the onset of body weight loss and diarrhea. IVIS was also applied in the dexamethasone treatment trial, and was a more sensitive indicator than body weight changes. All IVIS signals were parallel to the pathological abnormalities of the gut and immunological analysis results. In summary, IVIS provides both sensitive and objective means to monitor the disease course of transferred T cell-induced CD and fulfills the 3Rs principle of humane care of laboratory animals.
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Affiliation(s)
- Yu-Ling Chen
- National Laboratory Animal Center, National Applied Research Laboratories, Taipei, Taiwan
| | - Yi-Ting Chen
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | - Cheng-Feng Lo
- National Laboratory Animal Center, National Applied Research Laboratories, Taipei, Taiwan
| | - Ching-I Hsieh
- National Laboratory Animal Center, National Applied Research Laboratories, Taipei, Taiwan
| | - Shang-Yi Chiu
- National Laboratory Animal Center, National Applied Research Laboratories, Taipei, Taiwan
| | - Chang-Yen Wu
- National Laboratory Animal Center, National Applied Research Laboratories, Taipei, Taiwan
| | - Yu-Shan Yeh
- National Laboratory Animal Center, National Applied Research Laboratories, Taipei, Taiwan
| | - Shu-Hsuan Hung
- National Laboratory Animal Center, National Applied Research Laboratories, Taipei, Taiwan
| | - Po-Hao Cheng
- National Laboratory Animal Center, National Applied Research Laboratories, Taipei, Taiwan
| | - Yu-Hsuan Su
- National Laboratory Animal Center, National Applied Research Laboratories, Taipei, Taiwan
| | - Si-Tse Jiang
- National Laboratory Animal Center, National Applied Research Laboratories, Taipei, Taiwan
| | - Hsian-Jean Chin
- National Laboratory Animal Center, National Applied Research Laboratories, Taipei, Taiwan
| | - Yu-Chia Su
- National Laboratory Animal Center, National Applied Research Laboratories, Taipei, Taiwan
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21
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Mostafa HH, Vogel P, Srinivasan A, Russell CJ. Non-invasive Imaging of Sendai Virus Infection in Pharmacologically Immunocompromised Mice: NK and T Cells, but not Neutrophils, Promote Viral Clearance after Therapy with Cyclophosphamide and Dexamethasone. PLoS Pathog 2016; 12:e1005875. [PMID: 27589232 PMCID: PMC5010285 DOI: 10.1371/journal.ppat.1005875] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2016] [Accepted: 08/17/2016] [Indexed: 11/19/2022] Open
Abstract
In immunocompromised patients, parainfluenza virus (PIV) infections have an increased potential to spread to the lower respiratory tract (LRT), resulting in increased morbidity and mortality. Understanding the immunologic defects that facilitate viral spread to the LRT will help in developing better management protocols. In this study, we immunosuppressed mice with dexamethasone and/or cyclophosphamide then monitored the spread of viral infection into the LRT by using a noninvasive bioluminescence imaging system and a reporter Sendai virus (murine PIV type 1). Our results show that immunosuppression led to delayed viral clearance and increased viral loads in the lungs. After cessation of cyclophosphamide treatment, viral clearance occurred before the generation of Sendai-specific antibody responses and coincided with rebounds in neutrophils, T lymphocytes, and natural killer (NK) cells. Neutrophil suppression using anti-Ly6G antibody had no effect on infection clearance, NK-cell suppression using anti-NK antibody delayed clearance, and T-cell suppression using anti-CD3 antibody resulted in no clearance (chronic infection). Therapeutic use of hematopoietic growth factors G-CSF and GM-CSF had no effect on clearance of infection. In contrast, treatment with Sendai virus-specific polysera or a monoclonal antibody limited viral spread into the lungs and accelerated clearance. Overall, noninvasive bioluminescence was shown to be a useful tool to study respiratory viral progression, revealing roles for NK and T cells, but not neutrophils, in Sendai virus clearance after treatment with dexamethasone and cyclophosphamide. Virus-specific antibodies appear to have therapeutic potential.
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Affiliation(s)
- Heba H. Mostafa
- Department of Infectious Diseases, St. Jude Children’s Research Hospital, Memphis, Tennessee, United States of America
| | - Peter Vogel
- Department of Pathology, St. Jude Children’s Research Hospital, Memphis, Tennessee, United States of America
| | - Ashok Srinivasan
- Department of Bone Marrow Transplantation and Cellular Therapy, St. Jude Children’s Research Hospital, Memphis, Tennessee, United States of America
- Department of Pediatrics, College of Medicine, University of Tennessee Health Science Center, Memphis, Tennessee, United States of America
| | - Charles J. Russell
- Department of Infectious Diseases, St. Jude Children’s Research Hospital, Memphis, Tennessee, United States of America
- Department of Microbiology, Immunology & Biochemistry, College of Medicine, University of Tennessee Health Science Center, Memphis, Tennessee, United States of America
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22
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Balcan E. Quantitative approach to lectin-based glycoprofiling of thymic tissues in the control- and the dexamethasone-treated mice. Tissue Cell 2016; 48:168-82. [PMID: 27067421 DOI: 10.1016/j.tice.2016.03.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Revised: 03/22/2016] [Accepted: 03/22/2016] [Indexed: 12/18/2022]
Abstract
Dexamethasone (DEX) is the most commonly used synthetic glucocorticoid in treatment of various inflammatory conditions. Here we focused on evaluating the effect of DEX on apoptosis and glycan profile in the mouse thymic tissues. Histological examinations revealed that the DEX treatment cause severe alterations in thymus, such as disruption of thymic capsule, impaired epithelial cell-thymocyte contacts, cellular loss and increased apoptosis. The identification of thymic glycans in the control- and the DEX-treated mice was carried out by using a panel of five plant lectins, Maackia amurensis agglutinin (MAA), peanut agglutinin (PNA), Sambucus nigra agglutinin (SNA), Concanavalin A (ConA) and wheat germ agglutinin (WGA). Lectin histochemistry results showed that glycosylation pattern of thymus changes upon DEX treatment. For further detailed quantitative analyses of the binding intensities for each lectin, histochemical data were scored as high positive (HP), mild positive (MP) and low positive (LP) and differences among signaling densities were investigated. The staining patterns of thymic regions observed with lectin histochemistry suggest that DEX can affect the thymic glycan profile as well as thymocyte apoptosis. These results are consistent with the opinion that not only sialic acid, but also other sugar motifs may be responsible for thymocyte development.
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Affiliation(s)
- Erdal Balcan
- Celal Bayar University, Faculty of Arts and Science, Department of Biology, Molecular Biology Section, 45047, Muradiye Campus, Manisa, Turkey.
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23
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Kuthubutheen J, Smith L, Hwang E, Lin V. Preoperative steroids for hearing preservation cochlear implantation: A review. Cochlear Implants Int 2016; 17:63-74. [PMID: 26913646 DOI: 10.1080/14670100.2016.1148319] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Preoperative steroids have been shown to be beneficial in reducing the hearing loss associated with cochlear implantation. This review article discusses the mechanism of action, effects of differing routes of administration, and side effects of steroids administered to the inner ear. Studies on the role of preoperative steroids in animal and human studies are also examined and future directions for research in this area are discussed.
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Affiliation(s)
- Jafri Kuthubutheen
- a Department of Otolaryngology - Head and Neck Surgery , University of Toronto, Sunnybrook Health Sciences Centre , Ontario , Canada.,b Department of Otolaryngology - Head and Neck Surgery , School of Surgery, University of Western Australia , Perth , Australia
| | - Leah Smith
- a Department of Otolaryngology - Head and Neck Surgery , University of Toronto, Sunnybrook Health Sciences Centre , Ontario , Canada
| | - Euna Hwang
- a Department of Otolaryngology - Head and Neck Surgery , University of Toronto, Sunnybrook Health Sciences Centre , Ontario , Canada
| | - Vincent Lin
- a Department of Otolaryngology - Head and Neck Surgery , University of Toronto, Sunnybrook Health Sciences Centre , Ontario , Canada
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24
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Abstract
Studies over the past two decades have identified ceramide as a multifunctional central molecule in the sphingolipid biosynthetic pathway. Given its diverse tumor suppressive activities, molecular understanding of ceramide action will produce fundamental insights into processes that limit tumorigenesis and may identify key molecular targets for therapeutic intervention. Ceramide can be activated by a diverse array of stresses such as heat shock, genotoxic damage, oxidative stress and anticancer drugs. Ceramide triggers a variety of tumor suppressive and anti-proliferative cellular programs such as apoptosis, autophagy, senescence, and necroptosis by activating or repressing key effector molecules. Defects in ceramide generation and metabolism in cancer contribute to tumor cell survival and resistance to chemotherapy. The potent and versatile anticancer activity profile of ceramide has motivated drug development efforts to (re-)activate ceramide in established tumors. This review focuses on our current understanding of the tumor suppressive functions of ceramide and highlights the potential downstream targets of ceramide which are involved in its tumor suppressive action.
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25
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Sun Y, Fu A, Xu W, Chao JR, Moshiach S, Morris SW. Myeloid leukemia factor 1 interfered with Bcl-XL to promote apoptosis and its function was regulated by 14-3-3. J Physiol Biochem 2015; 71:807-21. [DOI: 10.1007/s13105-015-0445-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2015] [Accepted: 10/19/2015] [Indexed: 01/19/2023]
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Kuthubutheen J, Coates H, Rowsell C, Nedzelski J, Chen JM, Lin V. The role of extended preoperative steroids in hearing preservation cochlear implantation. Hear Res 2015; 327:257-64. [PMID: 26117408 DOI: 10.1016/j.heares.2015.06.010] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/03/2014] [Revised: 05/03/2015] [Accepted: 06/12/2015] [Indexed: 12/19/2022]
Abstract
INTRODUCTION Steroids have been shown to reduce the hearing threshold shifts associated with cochlear implantation. Previous studies have examined only the administration of steroids just prior to surgery. The aim of this study is to examine the role of extended preoperative systemic steroids in hearing preservation cochlear implantation. METHODS An animal model of cochlear implantation was used. 24 Hartley strain guinea pigs with a mean weight of 768 g and normal hearing were randomised into a control group, a second group receiving a single dose of systemic dexamethasone one day prior to surgery, and a third group receiving a daily dose of systemic dexamethasone for 5 days prior to surgery. A specially designed cochlear implant electrode by Med-EL (Innsbruck) was inserted through a dorsolateral approach to an insertion depth of 5 mm and left in-situ. Auditory brain stem responses at 8 kHz, 16 kHz and 32 kHz were measured preoperatively, and 1 week, 1 month and 2 months postoperatively. Cochlear histopathology was examined at the conclusion of the study. RESULTS At 1-week post operative, both groups receiving dexamethasone prior to implantation had smaller threshold shifts across all frequencies and which was significant at 32 kHz (p < 0.05). There were no differences among the three groups in the area of electrode related fibrosis. Spiral ganglion neuron (SGN) density was significantly higher in the group receiving steroids for 5 days, but only in the basal cochlear turn. DISCUSSION This is study demonstrates the benefits of extended preoperative systemic steroids on hearing outcomes and SGN density in an animal model of cochlear implantation surgery.
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Affiliation(s)
- Jafri Kuthubutheen
- Department of Otolaryngology - Head and Neck Surgery, Sunnybrook Health Sciences Centre, University of Toronto, 2075 Bayview Avenue, Toronto, Ontario, M4N 3M5, Canada; School of Surgery, University of Western Australia, Perth, Western Australia, Australia.
| | - Harvey Coates
- School of Surgery, University of Western Australia, Perth, Western Australia, Australia
| | - Corwyn Rowsell
- Department of Anatomic Pathology, Sunnybrook Health Sciences Centre, 2075 Bayview Avenue, Toronto, Ontario, M4N 3M5, Canada
| | - Julian Nedzelski
- Department of Otolaryngology - Head and Neck Surgery, Sunnybrook Health Sciences Centre, University of Toronto, 2075 Bayview Avenue, Toronto, Ontario, M4N 3M5, Canada
| | - Joseph M Chen
- Department of Otolaryngology - Head and Neck Surgery, Sunnybrook Health Sciences Centre, University of Toronto, 2075 Bayview Avenue, Toronto, Ontario, M4N 3M5, Canada
| | - Vincent Lin
- Department of Otolaryngology - Head and Neck Surgery, Sunnybrook Health Sciences Centre, University of Toronto, 2075 Bayview Avenue, Toronto, Ontario, M4N 3M5, Canada
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Tacke R, Hilgendorf I, Garner H, Waterborg C, Park K, Nowyhed H, Hanna RN, Wu R, Swirski FK, Geissmann F, Hedrick CC. The transcription factor NR4A1 is essential for the development of a novel macrophage subset in the thymus. Sci Rep 2015; 5:10055. [PMID: 26091486 PMCID: PMC4473761 DOI: 10.1038/srep10055] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2015] [Accepted: 03/20/2015] [Indexed: 12/23/2022] Open
Abstract
Tissue macrophages function to maintain homeostasis and regulate immune responses. While tissue macrophages derive from one of a small number of progenitor programs, the transcriptional requirements for site-specific macrophage subset development are more complex. We have identified a new tissue macrophage subset in the thymus and have discovered that its development is dependent on transcription factor NR4A1. Functionally, we find that NR4A1-dependent macrophages are critically important for clearance of apoptotic thymocytes. These macrophages are largely reduced or absent in mice lacking NR4A1, and Nr4a1-deficient mice have impaired thymocyte engulfment and clearance. Thus, NR4A1 functions as a master transcription factor for the development of this novel thymus-specific macrophage subset.
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Affiliation(s)
- Robert Tacke
- Division of Inflammation Biology, La Jolla Institute for Allergy and Immunology, La Jolla, California, USA
| | - Ingo Hilgendorf
- Center for Systems Biology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Hannah Garner
- Centre for Molecular and Cellular Biology of Inflammation, King’s College London, London, UK
| | - Claire Waterborg
- Division of Inflammation Biology, La Jolla Institute for Allergy and Immunology, La Jolla, California, USA
| | - Kiwon Park
- Division of Inflammation Biology, La Jolla Institute for Allergy and Immunology, La Jolla, California, USA
| | - Heba Nowyhed
- Division of Inflammation Biology, La Jolla Institute for Allergy and Immunology, La Jolla, California, USA
| | - Richard N. Hanna
- Division of Inflammation Biology, La Jolla Institute for Allergy and Immunology, La Jolla, California, USA
| | - Runpei Wu
- Division of Inflammation Biology, La Jolla Institute for Allergy and Immunology, La Jolla, California, USA
| | - Filip K. Swirski
- Center for Systems Biology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Frederic Geissmann
- Centre for Molecular and Cellular Biology of Inflammation, King’s College London, London, UK
| | - Catherine C. Hedrick
- Division of Inflammation Biology, La Jolla Institute for Allergy and Immunology, La Jolla, California, USA
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Petrillo MG, Fettucciari K, Montuschi P, Ronchetti S, Cari L, Migliorati G, Mazzon E, Bereshchenko O, Bruscoli S, Nocentini G, Riccardi C. Transcriptional regulation of kinases downstream of the T cell receptor: another immunomodulatory mechanism of glucocorticoids. BMC Pharmacol Toxicol 2014; 15:35. [PMID: 24993777 PMCID: PMC4105561 DOI: 10.1186/2050-6511-15-35] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2014] [Accepted: 06/25/2014] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Glucocorticoids affect peripheral immune responses, including modulation of T-cell activation, differentiation, and apoptosis. The quantity and quality of T-cell receptor (TCR)-triggered intracellular signals modulate T-cell function. Thus, glucocorticoids may affect T cells by interfering with the TCR signaling cascade. The purpose of the study was to search for glucocorticoid-modulated kinases downstream of the TCR. METHODS Gene modulation in lymphoid cells either treated with glucocorticoids or from glucocorticoid-treated mice was studied using a RNase protection assay, real-time PCR, and western blotting. The sensitivity of genetically modified thymocytes to glucocorticoid-induced apoptosis was studied by performing hypotonic propidium iodide staining and flow cytometry. The Student's t-test was employed for statistical evaluation. RESULTS We found that transcription of Itk, a non-receptor tyrosine kinase of the Tec family, was up-regulated in a mouse T-cell hybridoma by the synthetic glucocorticoid dexamethasone. In contrast, dexamethasone down-regulated the expression of Txk, a Tec kinase that functions redundantly with Itk, and Lck, the Src kinase immediately downstream of the TCR. We investigated the expression of Itk, Txk, and Lck in thymocytes and mature lymphocytes following in vitro and in vivo dexamethasone treatment at different time points and doses. Kinase expression was differentially modulated and followed distinct kinetics. Itk was up-regulated in all cell types and conditions tested. Txk was strongly up-regulated in mature lymphocytes but only weakly up-regulated or non-modulated in thymocytes in vitro or in vivo, respectively. Conversely, Lck was down-regulated in thymocytes, but not modulated or up-regulated in mature lymphocytes in the different experimental conditions. This complex behaviour correlates with the presence of both positive and negative glucocorticoid responsive elements (GRE and nGRE, respectively) in the Itk, Txk and Lck genes. To investigate the function associated with Itk up-regulation, dexamethasone-induced apoptosis of thymocytes from Itk-deficient mice was evaluated. Our results demonstrated that Itk deficiency causes increased sensitivity to dexamethasone but not to other pro-apoptotic stimuli. CONCLUSIONS Modulation of Itk, Txk, and Lck in thymocytes and mature lymphocytes is another mechanism by which glucocorticoids modulate T-cell activation and differentiation. Itk up-regulation plays a protective role in dexamethasone-treated thymocytes.
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Affiliation(s)
| | - Katia Fettucciari
- Department of Experimental Medicine, University of Perugia, Perugia, Italy
| | - Paolo Montuschi
- Department of Pharmacology, Faculty of Medicine, Catholic University of the Sacred Heart, Rome, Italy
| | | | - Luigi Cari
- Department of Medicine, University of Perugia, Perugia, Italy
| | | | - Emanuela Mazzon
- Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Centro Neurolesi “Bonino-Pulejo”, Messina, Italy
| | | | | | - Giuseppe Nocentini
- Department of Medicine, University of Perugia, Perugia, Italy
- Department of Medicine, Section of Pharmacology, Severi Square 1, University of Perugia, I-06132 San Sisto, Perugia, Italy
| | - Carlo Riccardi
- Department of Medicine, University of Perugia, Perugia, Italy
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Su H, Chen G, Gangadharmath U, Gomez LF, Liang Q, Mu F, Mocharla VP, Szardenings AK, Walsh JC, Xia CF, Yu C, Kolb HC. Evaluation of [(18)F]-CP18 as a PET imaging tracer for apoptosis. Mol Imaging Biol 2014; 15:739-47. [PMID: 23681757 DOI: 10.1007/s11307-013-0644-9] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
PURPOSE We identified and validated [(18)F]-CP18, a DEVD (the caspase 3 substrate recognition motif) containing substrate-based compound as an imaging tracer for caspase-3 activity in apoptotic cells. PROCEDURES CP18 was radiolabeled with fluorine-18 using click chemistry. The affinity and selectivity of CP18 for caspase-3 were evaluated in vitro. The biodistribution and metabolism pattern of [(18)F]-CP18 were assessed in vivo. [(18)F]-CP18 positron emission tomography (PET) scans were performed in a dexamethasone-induced thymic apoptosis mouse model. After imaging, the mice were sacrificed, and individual organs were collected, measured in a gamma counter, and tested for caspase-3 activity. RESULTS In vitro enzymatic caspase-3 assay demonstrated specific cleavage of CP18. In vivo, [(18)F]-CP18 is predominantly cleared through the kidneys and urine, and is rapidly eliminated from the bloodstream. There was a sixfold increase in caspase activity and a fourfold increase of [(18)F]-CP18 retention in the dexamethasone-induced thymus of treated versus control mice. CONCLUSIONS We report the use [(18)F]-CP18 as a PET tracer for imaging apoptosis. Our data support further development of this tracer for clinical PET applications.
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Affiliation(s)
- Helen Su
- Molecular Imaging Biomarker Research, Siemens Medical Solutions USA, Inc, 6100 Bristol Parkway, Culver City, CA, 90230, USA
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Wolff NC, McKay RM, Brugarolas J. REDD1/DDIT4-independent mTORC1 inhibition and apoptosis by glucocorticoids in thymocytes. Mol Cancer Res 2014; 12:867-77. [PMID: 24615339 DOI: 10.1158/1541-7786.mcr-13-0625] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
UNLABELLED Glucocorticoids induce apoptosis in lymphocytes and are commonly used to treat hematologic malignancies. However, they are also associated with significant adverse effects and their molecular mechanism of action is not fully understood. Glucocorticoid treatment induces expression of the mTORC1 inhibitor Regulated in Development and DNA Damage Response 1 (REDD1), also known as DNA-Damage Inducible Transcript 4 (DDIT4), and mTORC1 inhibition may distinguish glucocorticoid-sensitive from glucocorticoid-resistant acute lymphoblastic leukemia (ALL). Interestingly, REDD1 induction was impaired in glucocorticoid-resistant ALL cells and inhibition of mTORC1 using rapamycin restored glucocorticoid sensitivity. These data suggest that REDD1 may be essential for the response of ALL cells to glucocorticoids. To further investigate the role of REDD1, we evaluated the effects of glucocorticoids on primary thymocytes from wild-type and REDD1-deficient mice. Glucocorticoid-mediated apoptosis was blocked by a glucocorticoid receptor antagonist and by an inhibitor of transcription, which interfered with REDD1 induction and mTORC1 inhibition. However, REDD1 ablation had no effect on glucocorticoid-induced mTORC1 inhibition and apoptosis in thymocytes ex vivo. Overall, these data not only demonstrate the contextual differences of downstream signaling following glucocorticoid treatment but also provide a better mechanistic understanding of the role of REDD1. IMPLICATIONS These molecular findings underlying glucocorticoid action and the role of REDD1 are fundamental for the design of novel, more efficacious, and less toxic analogs. Mol Cancer Res; 12(6); 867-77. ©2014 AACR.
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Affiliation(s)
- Nicholas C Wolff
- Authors' Affiliations: Division of Hematology-Oncology, Department of Internal Medicine, Department of Developmental Biology, and the Kidney Cancer Program, Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, Dallas, Texas
| | | | - James Brugarolas
- Authors' Affiliations: Division of Hematology-Oncology, Department of Internal Medicine, Department of Developmental Biology, and the Kidney Cancer Program, Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, Dallas, Texas
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Lepletier A, de Carvalho VF, e Silva PMR, Villar S, Pérez AR, Savino W, Morrot A. Trypanosoma cruzi disrupts thymic homeostasis by altering intrathymic and systemic stress-related endocrine circuitries. PLoS Negl Trop Dis 2013; 7:e2470. [PMID: 24324845 PMCID: PMC3852165 DOI: 10.1371/journal.pntd.0002470] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2013] [Accepted: 08/27/2013] [Indexed: 01/01/2023] Open
Abstract
We have previously shown that experimental infection caused by Trypanosoma cruzi
is associated with changes in the hypothalamus-pituitary-adrenal axis. Increased glucocorticoid (GC)
levels are believed to be protective against the effects of acute stress during infection but result
in depletion of CD4+CD8+ thymocytes by apoptosis, driving to thymic
atrophy. However, very few data are available concerning prolactin (PRL), another stress-related
hormone, which seems to be decreased during T. cruzi infection. Considering the
immunomodulatory role of PRL upon the effects caused by GC, we investigated if intrathymic
cross-talk between GC and PRL receptors (GR and PRLR, respectively) might influence T.
cruzi-induced thymic atrophy. Using an acute experimental model, we observed changes in
GR/PRLR cross-activation related with the survival of CD4+CD8+
thymocytes during infection. These alterations were closely related with systemic changes,
characterized by a stress hormone imbalance, with progressive GC augmentation simultaneously to PRL
reduction. The intrathymic hormone circuitry exhibited an inverse modulation that seemed to
counteract the GC-related systemic deleterious effects. During infection, adrenalectomy protected
the thymus from the increase in apoptosis ratio without changing PRL levels, whereas an additional
inhibition of circulating PRL accelerated the thymic atrophy and led to an increase in
corticosterone systemic levels. These results demonstrate that the PRL impairment during infection
is not caused by the increase of corticosterone levels, but the opposite seems to occur.
Accordingly, metoclopramide (MET)-induced enhancement of PRL secretion protected thymic atrophy in
acutely infected animals as well as the abnormal export of immature and potentially autoreactive
CD4+CD8+ thymocytes to the periphery. In conclusion, our findings
clearly show that Trypanosoma cruzi subverts mouse thymus homeostasis by altering
intrathymic and systemic stress-related endocrine circuitries with major consequences upon the
normal process of intrathymic T cell development. It is currently estimated that 90 million people in America are exposed to T.
cruzi infection, the causative agent of Chagas disease. Despite the mortality and
morbidity, this infection is yet considered a neglected disease, due to the lack of effective, safe,
and affordable pharmaceuticals for controlling it. T. cruzi leads to
immunosuppression of the T cell compartment and to chronic cardiac inflammation, which seems to be
associated with the disruption of thymic homeostasis. Thymus atrophy, characteristic of acute
infection, is mainly associated with the loss of immature CD4+CD8+
thymocytes, which in turn is associated with increased corticosterone systemic levels, together with
their premature export to the periphery as potential autorreactive cells. Although being deleterious
to the thymus, GCs are protective during this infection, for avoiding an exacerbated
pro-inflammatory response. Here we demonstrate that the increase of GCs in plasma is related to the
impairment of PRL systemic levels. The intrathymic hormonal circuitry is also altered during
infection and an imbalance of the cross-talk involving GR and PRL is related with
CD4+CD8+ depletion. The partial restoration of PRL levels prevented
thymus atrophy of infected mice, thus partially reverting the T. cruzi-induced
subversion of the organ, ultimately reestablishing thymus homeostasis.
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Affiliation(s)
- Ailin Lepletier
- Laboratory of Thymus Research, Oswaldo Cruz Institute,
Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
| | | | | | - Silvina Villar
- Institute of Immunology, Faculty of Medical Sciences,
National University of Rosario and CONICET, Rosario, Argentina
| | - Ana Rosa Pérez
- Institute of Immunology, Faculty of Medical Sciences,
National University of Rosario and CONICET, Rosario, Argentina
| | - Wilson Savino
- Laboratory of Thymus Research, Oswaldo Cruz Institute,
Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
- * E-mail: ,
| | - Alexandre Morrot
- Laboratory of Thymus Research, Oswaldo Cruz Institute,
Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
- Laboratory of Immunobiology, Paulo de Goes Institute of
Microbiology, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
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Deep sequencing identification of novel glucocorticoid-responsive miRNAs in apoptotic primary lymphocytes. PLoS One 2013; 8:e78316. [PMID: 24250753 PMCID: PMC3824063 DOI: 10.1371/journal.pone.0078316] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2013] [Accepted: 09/11/2013] [Indexed: 01/01/2023] Open
Abstract
Apoptosis of lymphocytes governs the response of the immune system to environmental stress and toxic insult. Signaling through the ubiquitously expressed glucocorticoid receptor, stress-induced glucocorticoid hormones induce apoptosis via mechanisms requiring altered gene expression. Several reports have detailed the changes in gene expression mediating glucocorticoid-induced apoptosis of lymphocytes. However, few studies have examined the role of non-coding miRNAs in this essential physiological process. Previously, using hybridization-based gene expression analysis and deep sequencing of small RNAs, we described the prevalent post-transcriptional repression of annotated miRNAs during glucocorticoid-induced apoptosis of lymphocytes. Here, we describe the development of a customized bioinformatics pipeline that facilitates the deep sequencing-mediated discovery of novel glucocorticoid-responsive miRNAs in apoptotic primary lymphocytes. This analysis identifies the potential presence of over 200 novel glucocorticoid-responsive miRNAs. We have validated the expression of two novel glucocorticoid-responsive miRNAs using small RNA-specific qPCR. Furthermore, through the use of Ingenuity Pathways Analysis (IPA) we determined that the putative targets of these novel validated miRNAs are predicted to regulate cell death processes. These findings identify two and predict the presence of additional novel glucocorticoid-responsive miRNAs in the rat transcriptome, suggesting a potential role for both annotated and novel miRNAs in glucocorticoid-induced apoptosis of lymphocytes.
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Interleukin-21 accelerates thymic recovery from glucocorticoïd-induced atrophy. PLoS One 2013; 8:e72801. [PMID: 24023776 PMCID: PMC3759406 DOI: 10.1371/journal.pone.0072801] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2013] [Accepted: 07/11/2013] [Indexed: 12/20/2022] Open
Abstract
Both physiological and psychological stress cause thymic atrophy via glucocorticoïd (GC)-dependent apoptosis of double-positive (DP) thymocytes. Given the pervasiveness of stress, GC-induced thymic atrophy is arguably the most common type of acquired immunodeficiency. We recently reported that interleukin-21 (IL-21) has a unique ability to expand the small subset of DP thymocytes (CD69(+)) which are ongoing positive selection, and that administration of IL-21 increases thymic output in aged mice. The goal of this study was to evaluate whether IL-21 could mitigate GC-induced thymic atrophy. In contrast to double-negative (DN) and single-positive (SP) thymocytes, most DP thymocytes (CD69(-)) do not constitutively express the IL-21 receptor (IL-21R). Accordingly, CD69(-) DP thymocytes from PBS-treated mice were unresponsive to IL-21 administration. However, following GC injection, surviving CD69(-) DP thymocytes up-regulated IL-21R and responded to IL-21 treatment as evidenced by enhancement of Bcl6 expression and phosphorylation of STAT1, STAT3 and STAT5. Consequently, IL-21 administration to GC-treated mice accelerated thymic recovery by expanding considerably DP thymocytes and, to a lesser extent, DN thymocytes. However, IL-21-induced expansion of DN/DP thymocytes did not alter the diversity of the intrathymic or peripheral T-cell receptor (TCR) repertoire. We conclude that IL-21 dramatically accelerates recovery from GC-induced thymic atrophy.
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Müller N, Fischer HJ, Tischner D, van den Brandt J, Reichardt HM. Glucocorticoids Induce Effector T Cell Depolarization via ERM Proteins, Thereby Impeding Migration and APC Conjugation. THE JOURNAL OF IMMUNOLOGY 2013; 190:4360-70. [DOI: 10.4049/jimmunol.1201520] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Kłossowicz M, Scirka B, Suchanek J, Marek-Bukowiec K, Kisielow P, Aguado E, Miazek A. Assessment of caspase mediated degradation of linker for activation of T cells (LAT) at a single cell level. J Immunol Methods 2012; 389:9-17. [PMID: 23261919 DOI: 10.1016/j.jim.2012.12.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2012] [Revised: 12/10/2012] [Accepted: 12/11/2012] [Indexed: 12/29/2022]
Abstract
Caspase/Granzyme B mediated protein degradation is involved in elimination of activated T cell receptor (TCR) signaling molecules during processes of thymocyte selection and maintenance of peripheral homeostasis of T cells. Key components of TCR signaling cassette including LAT undergo biological inactivation in response to pro-apoptotic or anergy inducing environmental stimuli. Although available Western immunoblotting-based techniques are appropriate for detection of protein degradation in bulk populations of target cells, quantitative assessment of this process at a single cell level requires a different approach. Here we report on a novel, flow cytometry-based method for assessment of LAT integrity. This method exploits a loss of an anti-LAT antibody epitope recognition following proteolytic degradation of C-terminal domain of the LAT. We show that the LAT degradation precedes phosphatidylserine translocation to the outer leaflet of the plasma membrane and thus may constitute an early marker of T cell apoptosis. When used in conjunction with multi-parameter flow cytometry, our method revealed that FoxP3(+)CD4(+)CD8(low) thymocytes i.e. precursors of thymus derived CD4(+) regulatory T cells, in contrast to Foxp3(-)CD4(+)CD8(low) thymocytes are resistant to LAT degradation in response to CD3ε crosslinking. This finding can be used as an additional marker for T regulatory cell lineage.
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Affiliation(s)
- Mikołaj Kłossowicz
- Laboratory of Tumor Immunology, Department of Tumor Immunology, Ludwik Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Wroclaw, Poland
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Dietrich J, Rao K, Pastorino S, Kesari S. Corticosteroids in brain cancer patients: benefits and pitfalls. Expert Rev Clin Pharmacol 2012; 4:233-42. [PMID: 21666852 DOI: 10.1586/ecp.11.1] [Citation(s) in RCA: 226] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Glucocorticoids have been used for decades in the treatment of brain tumor patients and belong to the most powerful class of agents in reducing tumor-associated edema and minimizing side effects and the risk of encephalopathy in patients undergoing radiation therapy. Unfortunately, corticosteroids are associated with numerous and well-characterized adverse effects, constituting a major challenge in patients requiring long-term application of corticosteroids. Novel antiangiogenic agents, such as bevacizumab (Avastin®), which have been increasingly used in cancer patients, are associated with significant steroid-sparing effects, allowing neuro-oncologists to reduce the overall use of corticosteroids in patients with progressive malignant brain tumors. Recent experimental studies have revealed novel insights into the mechanisms and effects of corticosteroids in cancer patients, including modulation of tumor biology, angiogenesis and steroid-associated neurotoxicity. This article summarizes current concepts of using corticosteroids in brain cancer patients and highlights potential pitfalls in their effects on both tumor and neural progenitor cells.
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Affiliation(s)
- Jörg Dietrich
- MGH Cancer Center and Center for Regenerative Medicine, Harvard Medical School, Boston, MA, USA
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Nguyen HH, Tran BT, Muller W, Jack RS. IL-10 acts as a developmental switch guiding monocyte differentiation to macrophages during a murine peritoneal infection. THE JOURNAL OF IMMUNOLOGY 2012; 189:3112-20. [PMID: 22869902 DOI: 10.4049/jimmunol.1200360] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The peritoneal wash of BALB/c or C57BL/6 mice contains two populations of macrophages that differ in their level of expression of MHC class II (MHC II). Although both populations efficiently phagocytose bacteria in vivo, only the MHC II(lo) population is effective at phagocytosing apoptotic cells in vivo and only the MHC II(hi) population is effective at presenting Ag to T cells in vitro. Soon after induction of a peritoneal infection both of these macrophage populations are lost from the peritoneal wash fraction. Blood monocytes then enter the inflamed peritoneum and develop into new peritoneal macrophages. Whether these monocytes develop into MHC II(lo) or into MHC II(hi) macrophages is crucially dependent on the cytokine IL-10, which is transiently elevated in the peritoneal wash during the early phase of infection. Monocytes from CD45.1 animals transferred early in infection when the IL-10 concentration is high into congenic CD45.2 recipients develop into the MHC II(lo) macrophage population. Monocytes transferred later, when the IL-10 concentration has fallen, develop into the MHC II(hi) population. In infected IL-10-deficient animals monocytes fail to develop into the MHC II(lo) population but can be induced to do so by exogenous application of IL-10. Finally, high numbers of wild-type monocytes injected into IL-10R1-deficient animals develop into MHC II(lo) macrophages and were able by a bystander effect to induce the differentiation of the endogenous monocytes to the same fate.
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Affiliation(s)
- Huu-Hung Nguyen
- Department of Immunology, University of Greifswald, 17487 Greifswald, Germany
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Milhas D, Andrieu-Abadie N, Levade T, Benoist H, Ségui B. The tricyclodecan-9-yl-xanthogenate D609 triggers ceramide increase and enhances FasL-induced caspase-dependent and -independent cell death in T lymphocytes. Int J Mol Sci 2012; 13:8834-8852. [PMID: 22942738 PMCID: PMC3430269 DOI: 10.3390/ijms13078834] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2012] [Revised: 06/30/2012] [Accepted: 07/04/2012] [Indexed: 01/02/2023] Open
Abstract
D609 is known to modulate death receptor-induced ceramide generation and cell death. We show that in Jurkat cells, non-toxic D609 concentrations inhibit sphingomyelin synthase and, to a lesser extent, glucosylceramide synthase, and transiently increase the intracellular ceramide level. D609 significantly enhanced FasL-induced caspase activation and apoptosis. D609 stimulated FasL-induced cell death in caspase-8-deficient Jurkat cells, indicating that D609 acts downstream of caspase-8. At high FasL concentration (500 ng/mL), cell death was significantly, but not completely, inhibited by zVAD-fmk, a broad-spectrum caspase inhibitor, indicating that FasL can activate both caspase-dependent and -independent cell death signaling pathways. FasL-induced caspase activation was abolished by zVAD-fmk, whereas ceramide production was only partially impaired. D609 enhanced caspase-independent ceramide increase and cell death in response to FasL. Also, D609 overcame zVAD-fmk-conferred resistance to a FasL concentration as low as 50 ng/mL and bypassed RIP deficiency. It is likely that mitochondrial events were involved, since Bcl-xL over-expression impaired D609 effects. In PHA-activated human T lymphocytes, D609 enhanced FasL-induced cell death in the presence or absence of zVAD-fmk. Altogether, our data strongly indicate that the inhibition of ceramide conversion to complex sphingolipids by D609 is accompanied by an enhancement of FasL-induced caspase-dependent and -independent cell death in T lymphocytes.
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Affiliation(s)
- Delphine Milhas
- Team 4, Cancer Research Center of Toulouse, INSERM UMR1037, BP84225, 31432 Toulouse Cedex 4, France; E-Mails: (D.M.); (N.A.-A.); (T.L.); (H.B.)
| | - Nathalie Andrieu-Abadie
- Team 4, Cancer Research Center of Toulouse, INSERM UMR1037, BP84225, 31432 Toulouse Cedex 4, France; E-Mails: (D.M.); (N.A.-A.); (T.L.); (H.B.)
| | - Thierry Levade
- Team 4, Cancer Research Center of Toulouse, INSERM UMR1037, BP84225, 31432 Toulouse Cedex 4, France; E-Mails: (D.M.); (N.A.-A.); (T.L.); (H.B.)
| | - Hervé Benoist
- Team 4, Cancer Research Center of Toulouse, INSERM UMR1037, BP84225, 31432 Toulouse Cedex 4, France; E-Mails: (D.M.); (N.A.-A.); (T.L.); (H.B.)
- Department of Cell Biology, Hematology and Immunology, Faculty of Pharmaceutical Sciences, Paul Sabatier University (Toulouse III), 31062 Toulouse, France
| | - Bruno Ségui
- Team 4, Cancer Research Center of Toulouse, INSERM UMR1037, BP84225, 31432 Toulouse Cedex 4, France; E-Mails: (D.M.); (N.A.-A.); (T.L.); (H.B.)
- Department of Cell Biology, Hematology and Immunology, Faculty of Pharmaceutical Sciences, Paul Sabatier University (Toulouse III), 31062 Toulouse, France
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +33-5-61-32-35-31; Fax: +33-5-61-32-20-84
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Tome ME, Lee K, Jaramillo MC, Briehl MM. Mitochondria are the primary source of the H(2)O(2) signal for glucocorticoid-induced apoptosis of lymphoma cells. Exp Ther Med 2012; 4:237-242. [PMID: 22844350 DOI: 10.3892/etm.2012.595] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Glucocorticoids are a class of steroid hormones commonly used for the treatment of hematological malignancies due to their ability to induce apoptosis in lymphoid cells. An understanding of the critical steps in glucocorticoid-induced apoptosis is required to identify sources of drug resistance. Previously, we found that an increase in hydrogen peroxide is a necessary signal for glucocorticoid-induced apoptosis. In the current study, we found that mitochondria are the source of the signal. Glucocorticoid treatment inhibited Complex I and Complex III of the electron transport chain (ETC). Mitochondrial matrix reactive oxygen species (ROS) increased concomitantly with the oxidation of the mitochondrial glutathione pool. Treatment with Tiron, a superoxide scavenger, inhibited the signal. This suggests that the hydrogen peroxide signal originates as superoxide from the mitochondria and is metabolized to hydrogen peroxide. An inability to generate mitochondrial oxidants in response to glucocorticoids could cause drug resistance.
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Affiliation(s)
- Margaret E Tome
- Department of Pathology, University of Arizona, Tucson, AZ 85724, USA
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40
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Suarez PE, Rodriguez EG, Soundararajan R, Mérillat AM, Stehle JC, Rotman S, Roger T, Voirol MJ, Wang J, Gross O, Pétrilli V, Nadra K, Wilson A, Beermann F, Pralong FP, Maillard M, Pearce D, Chrast R, Rossier BC, Hummler E. The glucocorticoid-induced leucine zipper (gilz/Tsc22d3-2) gene locus plays a crucial role in male fertility. Mol Endocrinol 2012; 26:1000-13. [PMID: 22556341 DOI: 10.1210/me.2011-1249] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The glucocorticoid-induced leucine zipper (Tsc22d3-2) is a widely expressed dexamethasone-induced transcript that has been proposed to be important in immunity, adipogenesis, and renal sodium handling based on in vitro studies. To address its function in vivo, we have used Cre/loxP technology to generate mice deficient for Tsc22d3-2. Male knockout mice were viable but surprisingly did not show any major deficiencies in immunological processes or inflammatory responses. Tsc22d3-2 knockout mice adapted to a sodium-deprived diet and to water deprivation conditions but developed a subtle deficiency in renal sodium and water handling. Moreover, the affected animals developed a mild metabolic phenotype evident by a reduction in weight from 6 months of age, mild hyperinsulinemia, and resistance to a high-fat diet. Tsc22d3-2-deficient males were infertile and exhibited severe testis dysplasia from postnatal d 10 onward with increases in apoptotic cells within seminiferous tubules, an increased number of Leydig cells, and significantly elevated FSH and testosterone levels. Thus, our analysis of the Tsc22d3-2-deficient mice demonstrated a previously uncharacterized function of glucocorticoid-induced leucine zipper protein in testis development.
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Affiliation(s)
- Philippe Emmanuel Suarez
- Departments of Pharmacology and Toxicology, University of Lausanne, CH-1005 Lausanne, Switzerland
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41
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Functional polymeric nanoparticles for dexamethasone loading and release. Colloids Surf B Biointerfaces 2012; 93:59-66. [DOI: 10.1016/j.colsurfb.2011.12.008] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2011] [Revised: 12/06/2011] [Accepted: 12/08/2011] [Indexed: 11/20/2022]
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Wang H, Pang B, Li Y, Zhu D, Pang T, Liu Y. Dexamethasone has variable effects on mesenchymal stromal cells. Cytotherapy 2012; 14:423-30. [PMID: 22364108 DOI: 10.3109/14653249.2011.652735] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
BACKGROUND AIMS Dexamethasone (Dex) is a potent synthetic member of the glucocorticoid class of steroid drugs. Frequently, Dex has been used to enhance osteogenic, chondrogenic and adipogenic differentiation of mesenchymal stromal cells (MSC). Recently, Dex was applied to promote MSC proliferation, because of the rare frequency of MSC in bone marrow, and could protect the cells from apoptosis. The effects of Dex on MSC cytobiology behavior needs to be investigated. METHODS MSC were obtained from human umbilical cord. The surface phenotype and functional characterization of MSC cultured with different concentrations of Dex were investigated, in comparison with a control group, including MSC proliferation, apoptosis, cytokine expression and immunosuppression. RESULTS Different concentrations of Dex exerted diverse effects on MSC proliferation and apoptosis. Dex was also able to affect the pattern of cytokine expression of MSC. Furthermore, Dex impaired immunosuppression of MSC on peripheral blood mononuclear cells. CONCLUSIONS A low dose of Dex favors MSC expansion in vitro, and protects against apoptosis. It is not suitable for MSC to be pre-treated with Dex when they are to be used to treat immunologic disease. However, when MSC are applied to promote angiogenesis, it is beneficial for them to be pre-treated with 10(-9) mol/L Dex.
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Affiliation(s)
- Hanyu Wang
- The State Key Laboratory of Experimental Hematology, Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin, China
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43
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Helmrich U, Marsano A, Melly L, Wolff T, Christ L, Heberer M, Scherberich A, Martin I, Banfi A. Generation of human adult mesenchymal stromal/stem cells expressing defined xenogenic vascular endothelial growth factor levels by optimized transduction and flow cytometry purification. Tissue Eng Part C Methods 2011; 18:283-92. [PMID: 22070632 DOI: 10.1089/ten.tec.2011.0413] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Adult mesenchymal stromal/stem cells (MSCs) are a valuable source of multipotent progenitors for tissue engineering and regenerative medicine, but may require to be genetically modified to widen their efficacy in therapeutic applications. For example, overexpression of the angiogenic factor vascular endothelial growth factor (VEGF) at controlled levels is an attractive strategy to overcome the crucial bottleneck of graft vascularization and to avoid aberrant vascular growth. Since the regenerative potential of MSCs is rapidly lost during in vitro expansion, we sought to develop an optimized technique to achieve high-efficiency retroviral vector transduction of MSCs derived from both adipose tissue (adipose stromal cells, ASCs) or bone marrow (BMSCs) and rapidly select cells expressing desired levels of VEGF with minimal in vitro expansion. The proliferative peak of freshly isolated human ASCs and BMSCs was reached 4 and 6 days after plating, respectively. By performing retroviral vector transduction at this time point, >90% efficiency was routinely achieved before the first passage. MSCs were transduced with vectors expressing rat VEGF(164) quantitatively linked to a syngenic cell surface marker (truncated rat CD8). Retroviral transduction and VEGF expression did not affect MSC phenotype nor impair their in vitro proliferation and differentiation potential. Transgene expression was also maintained during in vitro differentiation. Furthermore, three subpopulations of transduced BMSCs homogeneously producing specific low, medium, and high VEGF doses could be prospectively isolated by flow cytometry based on the intensity of their CD8 expression already at the first passage. In conclusion, this optimized platform allowed the generation of populations of genetically modified MSCs, expressing specific levels of a therapeutic transgene, already at the first passage, thereby minimizing in vitro expansion and loss of regenerative potential.
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Affiliation(s)
- Uta Helmrich
- Cell and Gene Therapy, Department of Biomedicine, Basel University Hospital, Basel, Switzerland
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Tome ME, Jaramillo MC, Briehl MM. Hydrogen peroxide signaling is required for glucocorticoid-induced apoptosis in lymphoma cells. Free Radic Biol Med 2011; 51:2048-59. [PMID: 21964507 PMCID: PMC3208737 DOI: 10.1016/j.freeradbiomed.2011.09.002] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2011] [Revised: 09/01/2011] [Accepted: 09/01/2011] [Indexed: 12/21/2022]
Abstract
Glucocorticoid-induced apoptosis is exploited clinically for the treatment of hematologic malignancies. Determining the required molecular events for glucocorticoid-induced apoptosis will identify resistance mechanisms and suggest strategies for overcoming resistance. In this study, we found that glucocorticoid treatment of WEHI7.2 murine thymic lymphoma cells increased the steady-state [H(2)O(2)] and oxidized the intracellular redox environment before cytochrome c release. Removal of glucocorticoids after the H(2)O(2) increase resulted in a 30% clonogenicity; treatment with PEG-CAT increased clonogenicity to 65%. Human leukemia cell lines also showed increased H(2)O(2) in response to glucocorticoids and attenuated apoptosis after PEG-CAT treatment. WEHI7.2 cells that overexpress catalase (CAT2, CAT38) or were selected for resistance to H(2)O(2) (200R) removed enough of the H(2)O(2) generated by glucocorticoids to prevent oxidation of the intracellular redox environment. CAT2, CAT38, and 200R cells showed a 90-100% clonogenicity. The resistant cells maintained pERK survival signaling in response to glucocorticoids, whereas the sensitive cells did not. Treating the resistant cells with a MEK inhibitor sensitized them to glucocorticoids. These data indicate that: (1) an increase in H(2)O(2) is necessary for glucocorticoid-induced apoptosis in lymphoid cells, (2) increased H(2)O(2) removal causes glucocorticoid resistance, and (3) MEK inhibition can sensitize oxidative stress-resistant cells to glucocorticoids.
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Affiliation(s)
- Margaret E Tome
- Department of Pathology, University of Arizona, Tucson, AZ 85724, USA.
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45
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Tischner D, Theiss J, Karabinskaya A, van den Brandt J, Reichardt SD, Karow U, Herold MJ, Lühder F, Utermöhlen O, Reichardt HM. Acid sphingomyelinase is required for protection of effector memory T cells against glucocorticoid-induced cell death. THE JOURNAL OF IMMUNOLOGY 2011; 187:4509-16. [PMID: 21948986 DOI: 10.4049/jimmunol.1100911] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The activity of acid sphingomyelinase (aSMase) was previously reported to be involved in glucocorticoid-induced cell death (GICD) of T lymphocytes. This mechanism in turn is believed to contribute to the therapeutic efficacy of glucocorticoids (GCs) in the treatment of inflammatory diseases. In this study, we reassessed the role of aSMase in GICD by using aSMase knockout mice. The absence of aSMase largely abolished the partial protection that effector memory CD4(+) T cells in wild-type mice possess against GICD. Reduced IL-2 secretion by aSMase-deficient CD4(+) T cells suggested that a lack of this important survival factor might be the cause of these cells' enhanced susceptibility to GICD. Indeed, addition of IL-2 restored the protection against GICD, whereas neutralization of IL-2 abrogated the otherwise protective effect seen in wild-type effector memory CD4(+) T cells. The therapeutic implications of the altered sensitivity of aSMase-deficient T cells to GICD were assessed in models of inflammatory disorders; namely, experimental autoimmune encephalomyelitis and acute graft-versus-host disease. Surprisingly, GC treatment was equally efficient in both models in terms of ameliorating the diseases, regardless of the genotype of the T cells. Thus, our data reveal a hitherto unrecognized contribution of aSMase to the sensitivity of effector memory CD4(+) T cells to GICD and call into question the traditionally attributed importance of GICD of T cells to the treatment of inflammatory diseases by GCs.
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Affiliation(s)
- Denise Tischner
- Department of Cellular and Molecular Immunology, University of Göttingen Medical School, Göttingen 37073, Germany
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Tóth K, Sarang Z, Scholtz B, Brázda P, Ghyselinck N, Chambon P, Fésüs L, Szondy Z. Retinoids enhance glucocorticoid-induced apoptosis of T cells by facilitating glucocorticoid receptor-mediated transcription. Cell Death Differ 2011; 18:783-92. [PMID: 21072052 PMCID: PMC3131916 DOI: 10.1038/cdd.2010.136] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2010] [Revised: 09/20/2010] [Accepted: 09/30/2010] [Indexed: 11/09/2022] Open
Abstract
Glucocorticoid-induced apoptosis of thymocytes is one of the first recognized forms of programmed cell death. It was shown to require gene activation induced by the glucocorticoid receptor (GR) translocated into the nucleus following ligand binding. In addition, the necessity of the glucocorticoid-induced, but transcription-independent phosphorylation of phosphatidylinositol-specific phospholipase C (PI-PLC) has also been shown. Here we report that retinoic acids, physiological ligands for the nuclear retinoid receptors, enhance glucocorticoid-induced death of mouse thymocytes both in vitro and in vivo. The effect is mediated by retinoic acid receptor (RAR) alpha/retinoid X receptor (RXR) heterodimers, and occurs when both RARα and RXR are ligated by retinoic acids. We show that the ligated RARα/RXR interacts with the ligated GR, resulting in an enhanced transcriptional activity of the GR. The mechanism through which this interaction promotes GR-mediated transcription does not require DNA binding of the retinoid receptors and does not alter the phosphorylation status of Ser232, known to regulate the transcriptional activity of GR. Phosphorylation of PI-PLC was not affected. Besides thymocytes, retinoids also promoted glucocorticoid-induced apoptosis of various T-cell lines, suggesting that they could be used in the therapy of glucocorticoid-sensitive T-cell malignancies.
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Affiliation(s)
- K Tóth
- Apoptosis and Genomics Research Group, Department of Biochemistry and Molecular Biology, Hungarian Academy of Sciences, University of Debrecen, Debrecen, Hungary
| | - Z Sarang
- Apoptosis and Genomics Research Group, Department of Biochemistry and Molecular Biology, Hungarian Academy of Sciences, University of Debrecen, Debrecen, Hungary
| | - B Scholtz
- Apoptosis and Genomics Research Group, Department of Biochemistry and Molecular Biology, Hungarian Academy of Sciences, University of Debrecen, Debrecen, Hungary
| | - P Brázda
- Apoptosis and Genomics Research Group, Department of Biochemistry and Molecular Biology, Hungarian Academy of Sciences, University of Debrecen, Debrecen, Hungary
| | - N Ghyselinck
- Département de Biologie Cellulaire and Développement, Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Strasbourg, France
| | - P Chambon
- Département de Biologie Cellulaire and Développement, Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Strasbourg, France
| | - L Fésüs
- Apoptosis and Genomics Research Group, Department of Biochemistry and Molecular Biology, Hungarian Academy of Sciences, University of Debrecen, Debrecen, Hungary
| | - Z Szondy
- Apoptosis and Genomics Research Group, Department of Biochemistry and Molecular Biology, Hungarian Academy of Sciences, University of Debrecen, Debrecen, Hungary
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Increased inflammatory signaling and lethality of influenza H1N1 by nuclear thioredoxin-1. PLoS One 2011; 6:e18918. [PMID: 21526215 PMCID: PMC3078150 DOI: 10.1371/journal.pone.0018918] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2010] [Accepted: 03/25/2011] [Indexed: 01/30/2023] Open
Abstract
Background Cell culture studies show that the antioxidant thiol protein, thioredoxin-1 (Trx1), translocates to cell nuclei during stress, facilitates DNA binding of transcription factors NF-κB and glucocorticoid receptor (GR) and potentiates signaling in immune cells. Excessive proinflammatory signaling in vivo contributes to immune hyper-responsiveness and disease severity, but no studies have addressed whether nuclear Trx1 mediates such responses. Methodology/Principal Findings Transgenic mice (Tg) expressing human Trx1 (hTrx1) with added nuclear localization signal (NLS) showed broad tissue expression and nuclear localization. The role of nuclear Trx1 in inflammatory signaling was examined in Tg and wild-type (WT) mice following infection with influenza (H1N1) virus. Results showed that Tg mice had earlier and more extensive NF-κB activation, increased TNF-α and IL-6 expression, greater weight loss, slower recovery and increased mortality compared to WT. Decreased plasma glutathione (GSH) and oxidized plasma GSH/GSSG redox potential (EhGSSG) following infection in Tg mice showed that the increased nuclear thiol antioxidant caused a paradoxical downstream oxidative stress. An independent test of this nuclear reductive stress showed that glucocorticoid-induced thymocyte apoptosis was increased by NLS-Trx1. Conclusion/Significance Increased Trx1 in cell nuclei can increase severity of disease responses by potentiation of redox-sensitive transcription factor activation.
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Kfir-Erenfeld S, Sionov RV, Spokoini R, Cohen O, Yefenof E. Protein kinase networks regulating glucocorticoid-induced apoptosis of hematopoietic cancer cells: fundamental aspects and practical considerations. Leuk Lymphoma 2010; 51:1968-2005. [PMID: 20849387 DOI: 10.3109/10428194.2010.506570] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Glucocorticoids (GCs) are integral components in the treatment protocols of acute lymphoblastic leukemia, multiple myeloma, and non-Hodgkin lymphoma owing to their ability to induce apoptosis of these malignant cells. Resistance to GC therapy is associated with poor prognosis. Although they have been used in clinics for decades, the signal transduction pathways involved in GC-induced apoptosis have only partly been resolved. Accumulating evidence shows that this cell death process is mediated by a communication between nuclear GR affecting gene transcription of pro-apoptotic genes such as Bim, mitochondrial GR affecting the physiology of the mitochondria, and the protein kinase glycogen synthase kinase-3 (GSK3), which interacts with Bim following exposure to GCs. Prevention of Bim up-regulation, mitochondrial GR translocation, and/or GSK3 activation are common causes leading to GC therapy failure. Various protein kinases positively regulating the pro-survival Src-PI3K-Akt-mTOR and Raf-Ras-MEK-ERK signal cascades have been shown to be activated in malignant leukemic cells and antagonize GC-induced apoptosis by inhibiting GSK3 activation and Bim expression. Targeting these protein kinases has proven effective in sensitizing GR-positive malignant lymphoid cells to GC-induced apoptosis. Thus, intervening with the pro-survival kinase network in GC-resistant cells should be a good means of improving GC therapy of hematopoietic malignancies.
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Affiliation(s)
- Shlomit Kfir-Erenfeld
- The Lautenberg Center of Immunology and Cancer Research, Hebrew University-Hadassah Medical School, Jerusalem, Israel
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49
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Smith LK, Shah RR, Cidlowski JA. Glucocorticoids modulate microRNA expression and processing during lymphocyte apoptosis. J Biol Chem 2010; 285:36698-708. [PMID: 20847043 DOI: 10.1074/jbc.m110.162123] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Glucocorticoids modulate immune development and function through the induction of lymphocyte apoptosis via mechanisms requiring alterations in gene expression. Recently, short, noncoding, microRNAs have been identified as key regulators of lymphocyte function; however, it is unknown whether glucocorticoids regulate noncoding microRNAs and whether this regulation contributes to lymphocyte apoptosis. We now show by both microarray and deep sequencing analysis that microRNAs are substantially repressed during glucocorticoid-induced apoptosis of primary rat thymocytes. Mechanistic studies revealed that primary microRNA transcripts were not repressed, whereas the expression of the key microRNA processing enzymes: Dicer, Drosha, and DGCR8/Pasha, were significantly reduced at both the mRNA and protein levels during glucocorticoid-induced apoptosis. To delineate the role of Dicer depletion and microRNA repression in apoptosis, we silenced Dicer expression in two human leukemic cell lines and demonstrated that Dicer depletion significantly enhanced glucocorticoid-induced apoptosis in both model systems. Finally, in vitro and in vivo overexpression of the conserved miR-17-92 polycistron, which was repressed significantly by dexamethasone treatment in both our microarray and deep sequencing studies, blunted glucocorticoid-induced apoptosis. These studies provide evidence of altered post-transcriptional microRNA expression and the repression of the microRNA bioprocessing pathway during glucocorticoid-induced apoptosis of lymphocytes, suggesting a role for microRNA processors and specific microRNAs in cell life/death decisions.
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Affiliation(s)
- Lindsay K Smith
- Molecular Endocrinology Group, Laboratory of Signal Transduction, NIEHS, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, North Carolina 27709, USA
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Glucocorticoid-induced activation of caspase-8 protects the glucocorticoid-induced protein Gilz from proteasomal degradation and induces its binding to SUMO-1 in murine thymocytes. Cell Death Differ 2010; 18:183-90. [PMID: 20671745 DOI: 10.1038/cdd.2010.86] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
In this study, we evaluated the possible cross-talk between glucocorticoid (GC)-induced leucine zipper (Gilz) and caspase-8 in dexamethasone (Dex)-treated thymocytes. We determined that expression of Dex-induced Gilz protein was reduced when caspase-8 activity was inhibited, and this effect was not partially due to altered Gilz mRNA expression. Inhibition of the proteasome abrogated this reduction in Gilz expression, suggesting that Dex-induced caspase-8 activation protects Gilz from degradation. We hypothesized that the caspase-8-dependent protection of Gilz could be due to caspase-8-driven sumoylation. As a putative small ubiquitin-like modifier (SUMO)-binding site was identified in the Gilz sequence, we assessed whether SUMO-1 interacted with Gilz. We identified a 30-kDa protein that was compatible with the size of a Gilz-SUMO-1 complex and was recognized by the anti-SUMO-1 and anti-Gilz antibodies. In addition, Gilz bound to SUMO ubiquitin-conjugating (E2)-conjugating enzyme Ube21 (Ubc9), the specific SUMO-1 E2-conjugating enzyme, in vitro and coimmunoprecipitated with Ubc9 in vivo. Furthermore, Gilz coimmunoprecipitated with SUMO-1 both in vitro and in vivo, and this interaction depended on caspase-8 activation. This requirement for caspase-8 was further evaluated in caspase-8-deficient thymocytes and lymphocytes in which Gilz expression was reduced. In summary, our results suggest that caspase-8 activation protects Gilz from proteasomal degradation and induces its binding to SUMO-1 in GC-treated thymocytes.
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