1
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Nelson TA, Tommasini S, Fretz JA. Deletion of the transcription factor EBF1 in perivascular stroma disrupts skeletal homeostasis and precipitates premature aging of the marrow microenvironment. Bone 2024:117198. [PMID: 39002837 DOI: 10.1016/j.bone.2024.117198] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/13/2024] [Revised: 06/26/2024] [Accepted: 07/07/2024] [Indexed: 07/15/2024]
Abstract
Early B cell factor 1 (EBF1) is a transcription factor expressed by multiple lineages of stromal cells within the bone marrow. While cultures of Ebf1-deficient cells have been demonstrated to have impaired differentiation into either the osteoblast or adipogenic lineage in vitro by several groups, in vivo there has been a nominal consequence of the loss of EBF1 on skeletal development. In this study we used Prx-cre driven deletion of Ebf1 to eliminate EBF1 from the entire mesenchymal lineage of the skeleton and resolve this discrepancy. We report here that EBF1 is expressed primarily in the Mesenchymal Stem and Progenitor Cell (MSPC)-Adipo, MSPC-Osteo, and the Early Mesenchymal Progenitors, and that loss of EBF1 has a plethora of consequences to maintenance of the skeleton throughout adulthood. Stroma from the Prx-cre;Ebf1fl/fl bones had impaired osteogenic differentiation, an age-dependent loss of CFU-F, and elevated senescence accompanying Ebf1-deletion. New bone formation was reduced after 3 months, and resulted in a quiescent bone environment with fewer osteoblasts and an accompanied reduction in osteoclast-mediated remodeling. Consequently, bones were less ductile at a younger age, and deletion of EBF1 dramatically impaired fracture repair. Disruption of EBF1 in perivascular populations also rearranged the vascular network within these bones and disrupted cytokine signaling from key hematopoietic niches resulting in anemia, reductions in B cells, and myeloid skewing of marrow hematopoietic lineages. Mechanistically we observed disrupted BMP signaling within Ebf1-deficient progenitors with reduced SMAD1-phosphorylation, and elevated secretion of the soluble BMP-inhibitor Gremlin from the MSPC-Adipo cells. Ebf1-deficient progenitors also exhibited posttranslational suppression of glucocorticoid receptor expression. Together, these results suggest that EBF1 signaling is required for mesenchymal progenitor mobilization to maintain the adult skeleton, and that the primary action of EBF1 in the early mesenchymal lineage is to promote proliferation, and differentiation of these perivascular cells to sustain a healthy tissue.
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Affiliation(s)
- Tracy A Nelson
- Yale School of Medicine, Department of Orthopaedics and Rehabilitation, New Haven, CT 06510, United States of America
| | - Stephen Tommasini
- Yale School of Medicine, Department of Orthopaedics and Rehabilitation, New Haven, CT 06510, United States of America
| | - Jackie A Fretz
- Yale School of Medicine, Department of Orthopaedics and Rehabilitation, New Haven, CT 06510, United States of America.
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2
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Wolter A, Bucher CH, Kurmies S, Schreiner V, Konietschke F, Hohlbaum K, Klopfleisch R, Löhning M, Thöne-Reineke C, Buttgereit F, Huwyler J, Jirkof P, Rapp AE, Lang A. A buprenorphine depot formulation provides effective sustained post-surgical analgesia for 72 h in mouse femoral fracture models. Sci Rep 2023; 13:3824. [PMID: 36882427 PMCID: PMC9992384 DOI: 10.1038/s41598-023-30641-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Accepted: 02/27/2023] [Indexed: 03/09/2023] Open
Abstract
Adequate pain management is essential for ethical and scientific reasons in animal experiments and should completely cover the period of expected pain without the need for frequent re-application. However, current depot formulations of Buprenorphine are only available in the USA and have limited duration of action. Recently, a new microparticulate Buprenorphine formulation (BUP-Depot) for sustained release has been developed as a potential future alternative to standard formulations available in Europe. Pharmacokinetics indicate a possible effectiveness for about 72 h. Here, we investigated whether the administration of the BUP-Depot ensures continuous and sufficient analgesia in two mouse fracture models (femoral osteotomy) and could, therefore, serve as a potent alternative to the application of Tramadol via the drinking water. Both protocols were examined for analgesic effectiveness, side effects on experimental readout, and effects on fracture healing outcomes in male and female C57BL/6N mice. The BUP-Depot provided effective analgesia for 72 h, comparable to the effectiveness of Tramadol in the drinking water. Fracture healing outcome was not different between analgesic regimes. The availability of a Buprenorphine depot formulation for rodents in Europe would be a beneficial addition for extended pain relief in mice, thereby increasing animal welfare.
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Affiliation(s)
- Angelique Wolter
- Department of Rheumatology and Clinical Immunology, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany.
- German Rheumatism Research Centre (DRFZ), Leibniz Institute, Berlin, Germany.
- Institute of Animal Welfare, Animal Behavior and Laboratory Animal Science, Department of Veterinary Medicine, Freie Universität Berlin, Berlin, Germany.
| | - Christian H Bucher
- Julius Wolff Institute, Charité-Universitätsmedizin Berlin, Berlin, Germany
- Berlin Institute of Health Center for Regenerative Therapies (BCRT), Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Sebastian Kurmies
- Department of Rheumatology and Clinical Immunology, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
- German Rheumatism Research Centre (DRFZ), Leibniz Institute, Berlin, Germany
| | - Viktoria Schreiner
- Division of Pharmaceutical Technology, Department of Pharmaceutical Sciences, University of Basel, Basel, Switzerland
| | - Frank Konietschke
- Berlin Institute of Health Center for Regenerative Therapies (BCRT), Charité-Universitätsmedizin Berlin, Berlin, Germany
- Institute of Biometry and Clinical Epidemiology, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
| | - Katharina Hohlbaum
- Institute of Animal Welfare, Animal Behavior and Laboratory Animal Science, Department of Veterinary Medicine, Freie Universität Berlin, Berlin, Germany
- German Centre for the Protection of Laboratory Animals (Bf3R), German Federal Institute for Risk Assessment (BfR), Berlin, Germany
| | - Robert Klopfleisch
- Institute of Veterinary Pathology, Department of Veterinary Medicine, Freie Universität Berlin, Berlin, Germany
| | - Max Löhning
- Department of Rheumatology and Clinical Immunology, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
- German Rheumatism Research Centre (DRFZ), Leibniz Institute, Berlin, Germany
| | - Christa Thöne-Reineke
- Institute of Animal Welfare, Animal Behavior and Laboratory Animal Science, Department of Veterinary Medicine, Freie Universität Berlin, Berlin, Germany
| | - Frank Buttgereit
- Department of Rheumatology and Clinical Immunology, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
- German Rheumatism Research Centre (DRFZ), Leibniz Institute, Berlin, Germany
| | - Jörg Huwyler
- Division of Pharmaceutical Technology, Department of Pharmaceutical Sciences, University of Basel, Basel, Switzerland
| | - Paulin Jirkof
- Office for Animal Welfare and 3Rs, University of Zurich, Zurich, Switzerland
| | - Anna E Rapp
- Department of Rheumatology and Clinical Immunology, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
- German Rheumatism Research Centre (DRFZ), Leibniz Institute, Berlin, Germany
- Dr. Rolf M. Schwiete Research Unit for Osteoarthritis, Department of Orthopedics (Friedrichsheim), University Hospital Frankfurt, Goethe University, Frankfurt, Germany
| | - Annemarie Lang
- Department of Rheumatology and Clinical Immunology, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany.
- German Rheumatism Research Centre (DRFZ), Leibniz Institute, Berlin, Germany.
- Departments of Orthopaedic Surgery and Bioengineering, University of Pennsylvania, Philadelphia, PA, USA.
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3
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Roles of Local Soluble Factors in Maintaining the Growth Plate: An Update. Genes (Basel) 2023; 14:genes14030534. [PMID: 36980807 PMCID: PMC10048135 DOI: 10.3390/genes14030534] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Revised: 02/16/2023] [Accepted: 02/18/2023] [Indexed: 02/24/2023] Open
Abstract
The growth plate is a cartilaginous tissue found at the ends of growing long bones, which contributes to the lengthening of bones during development. This unique structure contains at least three distinctive layers, including resting, proliferative, and hypertrophic chondrocyte zones, maintained by a complex regulatory network. Due to its soft tissue nature, the growth plate is the most susceptible tissue of the growing skeleton to injury in childhood. Although most growth plate damage in fractures can heal, some damage can result in growth arrest or disorder, impairing leg length and resulting in deformity. In this review, we re-visit previously established knowledge about the regulatory network that maintains the growth plate and integrate current research displaying the most recent progress. Next, we highlight local secretary factors, such as Wnt, Indian hedgehog (Ihh), and parathyroid hormone-related peptide (PTHrP), and dissect their roles and interactions in maintaining cell function and phenotype in different zones. Lastly, we discuss future research topics that can further our understanding of this unique tissue. Given the unmet need to engineer the growth plate, we also discuss the potential of creating particular patterns of soluble factors and generating them in vitro.
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4
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Bensreti H, Alhamad DW, Gonzalez AM, Pizarro-Mondesir M, Bollag WB, Isales CM, McGee-Lawrence ME. Update on the Role of Glucocorticoid Signaling in Osteoblasts and Bone Marrow Adipocytes During Aging. Curr Osteoporos Rep 2023; 21:32-44. [PMID: 36564571 PMCID: PMC9936962 DOI: 10.1007/s11914-022-00772-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 11/15/2022] [Indexed: 12/25/2022]
Abstract
PURPOSE OF REVIEW Bone marrow adipose tissue (BMAT) in the skeleton likely plays a variety of physiological and pathophysiological roles that are not yet fully understood. In elucidating the complex relationship between bone and BMAT, glucocorticoids (GCs) are positioned to play a key role, as they have been implicated in the differentiation of bone marrow mesenchymal stem cells (BMSCs) between osteogenic and adipogenic lineages. The purpose of this review is to illuminate aspects of both endogenous and exogenous GC signaling, including the influence of GC receptors, in mechanisms of bone aging including relationships to BMAT. RECENT FINDINGS Harmful effects of GCs on bone mass involve several cellular pathways and events that can include BMSC differentiation bias toward adipogenesis and the influence of mature BMAT on bone remodeling through crosstalk. Interestingly, BMAT involvement remains poorly explored in GC-induced osteoporosis and warrants further investigation. This review provides an update on the current understanding of the role of glucocorticoids in the biology of osteoblasts and bone marrow adipocytes (BMAds).
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Affiliation(s)
- Husam Bensreti
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, GA, USA
| | - Dima W Alhamad
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, GA, USA
| | - Alejandro Marrero Gonzalez
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, GA, USA
| | - Manuel Pizarro-Mondesir
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, GA, USA
| | - Wendy B Bollag
- Department of Physiology, Medical College of Georgia, Augusta University, Augusta, GA, USA
- Charlie Norwood VA Medical Center, Augusta, GA, USA
| | - Carlos M Isales
- Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, Augusta University, Augusta, GA, USA
- Department of Orthopaedic Surgery, Medical College of Georgia, Augusta University, Augusta, GA, USA
- Department of Medicine, Medical College of Georgia, Augusta University, Augusta, GA, USA
| | - Meghan E McGee-Lawrence
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, Augusta, GA, USA.
- Department of Orthopaedic Surgery, Medical College of Georgia, Augusta University, Augusta, GA, USA.
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5
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Saul D, Khosla S. Fracture Healing in the Setting of Endocrine Diseases, Aging, and Cellular Senescence. Endocr Rev 2022; 43:984-1002. [PMID: 35182420 PMCID: PMC9695115 DOI: 10.1210/endrev/bnac008] [Citation(s) in RCA: 29] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Indexed: 11/19/2022]
Abstract
More than 2.1 million age-related fractures occur in the United States annually, resulting in an immense socioeconomic burden. Importantly, the age-related deterioration of bone structure is associated with impaired bone healing. Fracture healing is a dynamic process which can be divided into four stages. While the initial hematoma generates an inflammatory environment in which mesenchymal stem cells and macrophages orchestrate the framework for repair, angiogenesis and cartilage formation mark the second healing period. In the central region, endochondral ossification favors soft callus development while next to the fractured bony ends, intramembranous ossification directly forms woven bone. The third stage is characterized by removal and calcification of the endochondral cartilage. Finally, the chronic remodeling phase concludes the healing process. Impaired fracture healing due to aging is related to detrimental changes at the cellular level. Macrophages, osteocytes, and chondrocytes express markers of senescence, leading to reduced self-renewal and proliferative capacity. A prolonged phase of "inflammaging" results in an extended remodeling phase, characterized by a senescent microenvironment and deteriorating healing capacity. Although there is evidence that in the setting of injury, at least in some tissues, senescent cells may play a beneficial role in facilitating tissue repair, recent data demonstrate that clearing senescent cells enhances fracture repair. In this review, we summarize the physiological as well as pathological processes during fracture healing in endocrine disease and aging in order to establish a broad understanding of the biomechanical as well as molecular mechanisms involved in bone repair.
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Affiliation(s)
- Dominik Saul
- Kogod Center on Aging and Division of Endocrinology, Mayo Clinic, Rochester, Minnesota 55905, USA.,Department of Trauma, Orthopedics and Reconstructive Surgery, Georg-August-University of Goettingen, 37073 Goettingen, Germany
| | - Sundeep Khosla
- Kogod Center on Aging and Division of Endocrinology, Mayo Clinic, Rochester, Minnesota 55905, USA
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6
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Schoppa AM, Chen X, Ramge JM, Vikman A, Fischer V, Haffner-Luntzer M, Riegger J, Tuckermann J, Scharffetter-Kochanek K, Ignatius A. Osteoblast lineage Sod2 deficiency leads to an osteoporosis-like phenotype in mice. Dis Model Mech 2022; 15:274992. [PMID: 35394023 PMCID: PMC9118037 DOI: 10.1242/dmm.049392] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Accepted: 03/25/2022] [Indexed: 12/19/2022] Open
Abstract
Osteoporosis is a systemic metabolic skeletal disease characterized by low bone mass and strength associated with fragility fractures. Oxidative stress, which results from elevated intracellular reactive oxygen species (ROS) and arises in the aging organism, is considered one of the critical factors contributing to osteoporosis. Mitochondrial (mt)ROS, as the superoxide anion (O2−) generated during mitochondrial respiration, are eliminated in the young organism by antioxidant defense mechanisms, including superoxide dismutase 2 (SOD2), the expression and activity of which are decreased in aging mesenchymal progenitor cells, accompanied by increased mtROS production. Using a mouse model of osteoblast lineage cells with Sod2 deficiency, we observed significant bone loss in trabecular and cortical bones accompanied by decreased osteoblast activity, increased adipocyte accumulation in the bone marrow and augmented osteoclast activity, suggestive of altered mesenchymal progenitor cell differentiation and osteoclastogenesis. Furthermore, osteoblast senescence was increased. To date, there are only a few studies suggesting a causal association between mtROS and cellular senescence in tissue in vivo. Targeting SOD2 to improve redox homeostasis could represent a potential therapeutic strategy for maintaining bone health during aging. Summary: Osteoblast-lineage specific Sod2 deficiency in mice leads to increased mtROS, impaired osteoblast function, increased adipogenesis, increased osteoclast activity and increased osteoblast senescence, resulting in bone loss.
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Affiliation(s)
- Astrid M Schoppa
- Institute of Orthopedic Research and Biomechanics, Ulm University Medical Center, 89081 Ulm, Germany
| | - Xiangxu Chen
- Institute of Orthopedic Research and Biomechanics, Ulm University Medical Center, 89081 Ulm, Germany
| | - Jan-Moritz Ramge
- Institute of Orthopedic Research and Biomechanics, Ulm University Medical Center, 89081 Ulm, Germany
| | - Anna Vikman
- Institute of Orthopedic Research and Biomechanics, Ulm University Medical Center, 89081 Ulm, Germany
| | - Verena Fischer
- Institute of Orthopedic Research and Biomechanics, Ulm University Medical Center, 89081 Ulm, Germany
| | - Melanie Haffner-Luntzer
- Institute of Orthopedic Research and Biomechanics, Ulm University Medical Center, 89081 Ulm, Germany
| | - Jana Riegger
- Department of Orthopedics, Division for Biochemistry of Joint and Connective Tissue Diseases, Ulm University Medical Center, 89081 Ulm, Germany
| | - Jan Tuckermann
- Institute of Comparative Molecular Endocrinology, Ulm University, 89081 Ulm, Germany
| | | | - Anita Ignatius
- Institute of Orthopedic Research and Biomechanics, Ulm University Medical Center, 89081 Ulm, Germany
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7
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Ahmad M, Krüger BT, Kroll T, Vettorazzi S, Dorn AK, Mengele F, Lee S, Nandi S, Yilmaz D, Stolz M, Tangudu NK, Vázquez DC, Pachmayr J, Cirstea IC, Spasic MV, Ploubidou A, Ignatius A, Tuckermann J. Inhibition of Cdk5 increases osteoblast differentiation and bone mass and improves fracture healing. Bone Res 2022; 10:33. [PMID: 35383146 PMCID: PMC8983726 DOI: 10.1038/s41413-022-00195-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Revised: 12/10/2021] [Accepted: 12/21/2021] [Indexed: 11/09/2022] Open
Abstract
Identification of regulators of osteoblastogenesis that can be pharmacologically targeted is a major goal in combating osteoporosis, a common disease of the elderly population. Here, unbiased kinome RNAi screening in primary murine osteoblasts identified cyclin-dependent kinase 5 (Cdk5) as a suppressor of osteoblast differentiation in both murine and human preosteoblastic cells. Cdk5 knockdown by siRNA, genetic deletion using the Cre-loxP system, or inhibition with the small molecule roscovitine enhanced osteoblastogenesis in vitro. Roscovitine treatment significantly enhanced bone mass by increasing osteoblastogenesis and improved fracture healing in mice. Mechanistically, downregulation of Cdk5 expression increased Erk phosphorylation, resulting in enhanced osteoblast-specific gene expression. Notably, simultaneous Cdk5 and Erk depletion abrogated the osteoblastogenesis conferred by Cdk5 depletion alone, suggesting that Cdk5 regulates osteoblast differentiation through MAPK pathway modulation. We conclude that Cdk5 is a potential therapeutic target to treat osteoporosis and improve fracture healing.
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Affiliation(s)
- Mubashir Ahmad
- Institute of Comparative Molecular Endocrinology (CME), Ulm University, Helmholtzstrasse 8/1, 89081, Ulm, Germany.,Institute of Orthopedic Research and Biomechanics, Ulm University, Helmholtzstrasse 14, 89081, Ulm, Germany
| | - Benjamin Thilo Krüger
- Institute of Orthopedic Research and Biomechanics, Ulm University, Helmholtzstrasse 14, 89081, Ulm, Germany
| | - Torsten Kroll
- Leibniz Institute on Aging - Fritz Lipmann Institute (FLI), Beutenbergstrasse 11, D-07745, Jena, Germany
| | - Sabine Vettorazzi
- Institute of Comparative Molecular Endocrinology (CME), Ulm University, Helmholtzstrasse 8/1, 89081, Ulm, Germany
| | - Ann-Kristin Dorn
- Institute of Comparative Molecular Endocrinology (CME), Ulm University, Helmholtzstrasse 8/1, 89081, Ulm, Germany
| | - Florian Mengele
- Praxisklinik für Orthopädie, Unfall- und Neurochirurgie Prof. Bischoff/Dr. Spies/Dr. Mengele, 89231, Neu-Ulm, Germany
| | - Sooyeon Lee
- Institute of Comparative Molecular Endocrinology (CME), Ulm University, Helmholtzstrasse 8/1, 89081, Ulm, Germany
| | - Sayantan Nandi
- Institute of Comparative Molecular Endocrinology (CME), Ulm University, Helmholtzstrasse 8/1, 89081, Ulm, Germany
| | - Dilay Yilmaz
- Institute of Comparative Molecular Endocrinology (CME), Ulm University, Helmholtzstrasse 8/1, 89081, Ulm, Germany
| | - Miriam Stolz
- Institute of Comparative Molecular Endocrinology (CME), Ulm University, Helmholtzstrasse 8/1, 89081, Ulm, Germany
| | - Naveen Kumar Tangudu
- Institute of Comparative Molecular Endocrinology (CME), Ulm University, Helmholtzstrasse 8/1, 89081, Ulm, Germany.,UPMC Hillman Cancer Center, Department of Pharmacology and Chemical Biology, University of Pittsburgh, 5115 Center Avenue, 15232, Pittsburgh, PA, USA
| | - David Carro Vázquez
- Institute of Comparative Molecular Endocrinology (CME), Ulm University, Helmholtzstrasse 8/1, 89081, Ulm, Germany.,TAmiRNA GmbH, Leberstrasse 20, 1110, Vienna, Austria
| | - Johanna Pachmayr
- Paracelsus Medizinische Privatuniverstät, Institute of Pharmacy, Strubergasse 21, 5020, Salzburg, Austria
| | - Ion Cristian Cirstea
- Institute of Comparative Molecular Endocrinology (CME), Ulm University, Helmholtzstrasse 8/1, 89081, Ulm, Germany
| | - Maja Vujic Spasic
- Institute of Comparative Molecular Endocrinology (CME), Ulm University, Helmholtzstrasse 8/1, 89081, Ulm, Germany
| | - Aspasia Ploubidou
- Leibniz Institute on Aging - Fritz Lipmann Institute (FLI), Beutenbergstrasse 11, D-07745, Jena, Germany
| | - Anita Ignatius
- Institute of Orthopedic Research and Biomechanics, Ulm University, Helmholtzstrasse 14, 89081, Ulm, Germany
| | - Jan Tuckermann
- Institute of Comparative Molecular Endocrinology (CME), Ulm University, Helmholtzstrasse 8/1, 89081, Ulm, Germany. .,Department of Endocrinology, Ludwig Maximilians University Munich, Munich, 80336, Germany.
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8
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Inhibition of Cdk5 Ameliorates Skeletal Bone Loss in Glucocorticoid-Treated Mice. Biomedicines 2022; 10:biomedicines10020404. [PMID: 35203613 PMCID: PMC8962259 DOI: 10.3390/biomedicines10020404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Revised: 02/02/2022] [Accepted: 02/05/2022] [Indexed: 11/16/2022] Open
Abstract
Glucocorticoids (GCs) are widely used to treat inflammatory diseases. However, their long-term use leads to glucocorticoid-induced osteoporosis, increasing morbidity and mortality. Both anabolic and anti-resorptive drugs are used to counteract GC-induced bone loss, however, they are expensive and/or have major side effects. Therefore, identifying new targets for cost-effective, small-molecule inhibitors is essential. We recently identified cyclin-dependent kinase 5 (Cdk5) as a suppressor of osteoblast differentiation and showed that its inhibition with roscovitine promoted osteoblastogenesis, thus improving the skeletal bone mass and fracture healing. Here, we assessed whether Cdk5 knockdown or inhibition could also reverse the GC-mediated suppression of osteoblast differentiation, bone loss, and fracture healing. We first demonstrated that Cdk5 silencing abolished the dexamethasone (Dex)-induced downregulation of alkaline phosphatase (Alp) activity, osteoblast-specific marker gene expression (Runx2, Sp7, Alpl, and Bglap), and mineralization. Similarly, Cdk5 inhibition rescued Dex-induced suppression of Alp activity. We further demonstrated that Cdk5 inhibition reversed prednisolone (Pred)-induced bone loss in mice, due to reduced osteoclastogenesis rather than improved osteoblastogenesis. Moreover, we revealed that Cdk5 inhibition failed to improve Pred-mediated impaired fracture healing. Taken together, we demonstrated that Cdk5 inhibition with roscovitine ameliorated GC-mediated bone loss but did not reverse GC-induced compromised fracture healing in mice.
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9
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Garcia J, Smith SS, Karki S, Drissi H, Hrdlicka HH, Youngstrom DW, Delany AM. miR-433-3p suppresses bone formation and mRNAs critical for osteoblast function in mice. J Bone Miner Res 2021; 36:1808-1822. [PMID: 34004029 DOI: 10.1002/jbmr.4339] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Revised: 05/03/2021] [Accepted: 05/10/2021] [Indexed: 12/16/2022]
Abstract
MicroRNAs (miRNAs) are key posttranscriptional regulators of osteoblastic commitment and differentiation. miR-433-3p was previously shown to target Runt-related transcription factor 2 (Runx2) and to be repressed by bone morphogenetic protein (BMP) signaling. Here, we show that miR-433-3p is progressively decreased during osteoblastic differentiation of primary mouse bone marrow stromal cells in vitro, and we confirm its negative regulation of this process. Although repressors of osteoblastic differentiation often promote adipogenesis, inhibition of miR-433-3p did not affect adipocyte differentiation in vitro. Multiple pathways regulate osteogenesis. Using luciferase-3' untranslated region (UTR) reporter assays, five novel miR-433-3p targets involved in parathyroid hormone (PTH), mitogen-activated protein kinase (MAPK), Wnt, and glucocorticoid signaling pathways were validated. We show that Creb1 is a miR-433-3p target, and this transcription factor mediates key signaling downstream of PTH receptor activation. We also show that miR-433-3p targets hydroxysteroid 11-β dehydrogenase 1 (Hsd11b1), the enzyme that locally converts inactive glucocorticoids to their active form. miR-433-3p dampens glucocorticoid signaling, and targeting of Hsd11b1 could contribute to this phenomenon. Moreover, miR-433-3p targets R-spondin 3 (Rspo3), a leucine-rich repeat-containing G-protein coupled receptor (LGR) ligand that enhances Wnt signaling. Notably, Wnt canonical signaling is also blunted by miR-433-3p activity. In vivo, expression of a miR-433-3p inhibitor or tough decoy in the osteoblastic lineage increased trabecular bone volume. Mice expressing the miR-433-3p tough decoy displayed increased bone formation without alterations in osteoblast or osteoclast numbers or surface, indicating that miR-433-3p decreases osteoblast activity. Overall, we showed that miR-433-3p is a negative regulator of bone formation in vivo, targeting key bone-anabolic pathways including those involved in PTH signaling, Wnt, and endogenous glucocorticoids. Local delivery of miR-433-3p inhibitor could present a strategy for the management of bone loss disorders and bone defect repair. © 2021 American Society for Bone and Mineral Research (ASBMR).
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Affiliation(s)
- John Garcia
- Center for Molecular Oncology, UConn Health, Farmington, Connecticut, USA
| | - Spenser S Smith
- Center for Molecular Oncology, UConn Health, Farmington, Connecticut, USA
| | - Sangita Karki
- Center for Molecular Oncology, UConn Health, Farmington, Connecticut, USA
| | - Hicham Drissi
- Department of Orthopaedics, Emory University and Atlanta VA Medical Center, Decatur, Georgia, USA
| | - Henry H Hrdlicka
- Center for Molecular Oncology, UConn Health, Farmington, Connecticut, USA
| | - Daniel W Youngstrom
- Department of Orthopedic Surgery, UConn Health, Farmington, Connecticut, USA
| | - Anne M Delany
- Center for Molecular Oncology, UConn Health, Farmington, Connecticut, USA
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10
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Giroud M, Tsokanos FF, Caratti G, Kotschi S, Khani S, Jouffe C, Vogl ES, Irmler M, Glantschnig C, Gil-Lozano M, Hass D, Khan AA, Garcia MR, Mattijssen F, Maida A, Tews D, Fischer-Posovszky P, Feuchtinger A, Virtanen KA, Beckers J, Wabitsch M, Uhlenhaut H, Blüher M, Tuckermann J, Scheideler M, Bartelt A, Herzig S. HAND2 is a novel obesity-linked adipogenic transcription factor regulated by glucocorticoid signalling. Diabetologia 2021; 64:1850-1865. [PMID: 34014371 PMCID: PMC8245394 DOI: 10.1007/s00125-021-05470-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/14/2020] [Accepted: 02/18/2021] [Indexed: 11/01/2022]
Abstract
AIMS/HYPOTHESIS Adipocytes are critical cornerstones of energy metabolism. While obesity-induced adipocyte dysfunction is associated with insulin resistance and systemic metabolic disturbances, adipogenesis, the formation of new adipocytes and healthy adipose tissue expansion are associated with metabolic benefits. Understanding the molecular mechanisms governing adipogenesis is of great clinical potential to efficiently restore metabolic health in obesity. Here we investigate the role of heart and neural crest derivatives-expressed 2 (HAND2) in adipogenesis. METHODS Human white adipose tissue (WAT) was collected from two cross-sectional studies of 318 and 96 individuals. In vitro, for mechanistic experiments we used primary adipocytes from humans and mice as well as human multipotent adipose-derived stem (hMADS) cells. Gene silencing was performed using siRNA or genetic inactivation in primary adipocytes from loxP and or tamoxifen-inducible Cre-ERT2 mouse models with Cre-encoding mRNA or tamoxifen, respectively. Adipogenesis and adipocyte metabolism were measured by Oil Red O staining, quantitative PCR (qPCR), microarray, glucose uptake assay, western blot and lipolysis assay. A combinatorial RNA sequencing (RNAseq) and ChIP qPCR approach was used to identify target genes regulated by HAND2. In vivo, we created a conditional adipocyte Hand2 deletion mouse model using Cre under control of the Adipoq promoter (Hand2AdipoqCre) and performed a large panel of metabolic tests. RESULTS We found that HAND2 is an obesity-linked white adipocyte transcription factor regulated by glucocorticoids that was necessary but insufficient for adipocyte differentiation in vitro. In a large cohort of humans, WAT HAND2 expression was correlated to BMI. The HAND2 gene was enriched in white adipocytes compared with brown, induced early in differentiation and responded to dexamethasone (DEX), a typical glucocorticoid receptor (GR, encoded by NR3C1) agonist. Silencing of NR3C1 in hMADS cells or deletion of GR in a transgenic conditional mouse model results in diminished HAND2 expression, establishing that adipocyte HAND2 is regulated by glucocorticoids via GR in vitro and in vivo. Furthermore, we identified gene clusters indirectly regulated by the GR-HAND2 pathway. Interestingly, silencing of HAND2 impaired adipocyte differentiation in hMADS and primary mouse adipocytes. However, a conditional adipocyte Hand2 deletion mouse model using Cre under control of the Adipoq promoter did not mirror these effects on adipose tissue differentiation, indicating that HAND2 was required at stages prior to Adipoq expression. CONCLUSIONS/INTERPRETATION In summary, our study identifies HAND2 as a novel obesity-linked adipocyte transcription factor, highlighting new mechanisms of GR-dependent adipogenesis in humans and mice. DATA AVAILABILITY Array data have been submitted to the GEO database at NCBI (GSE148699).
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Affiliation(s)
- Maude Giroud
- Institute for Diabetes and Cancer (IDC); Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
- German Center for Diabetes Research (DZD), Neuherberg, Germany
- Joint Heidelberg-IDC Translational Diabetes Program, Inner Medicine 1, Heidelberg University Hospital, Heidelberg, Germany
- Institute for Cardiovascular Prevention (IPEK), Ludwig-Maximilians-University, Munich, Germany
| | - Foivos-Filippos Tsokanos
- Institute for Diabetes and Cancer (IDC); Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
- German Center for Diabetes Research (DZD), Neuherberg, Germany
- Joint Heidelberg-IDC Translational Diabetes Program, Inner Medicine 1, Heidelberg University Hospital, Heidelberg, Germany
| | - Giorgio Caratti
- Institute for Comparative Molecular Endocrinology, Universität Ulm, Ulm, Germany
| | - Stefan Kotschi
- Institute for Cardiovascular Prevention (IPEK), Ludwig-Maximilians-University, Munich, Germany
| | - Sajjad Khani
- Institute for Diabetes and Cancer (IDC); Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
- Institute for Cardiovascular Prevention (IPEK), Ludwig-Maximilians-University, Munich, Germany
| | - Céline Jouffe
- Institute for Diabetes and Cancer (IDC); Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
| | - Elena S Vogl
- Institute for Diabetes and Cancer (IDC); Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
- German Center for Diabetes Research (DZD), Neuherberg, Germany
- Joint Heidelberg-IDC Translational Diabetes Program, Inner Medicine 1, Heidelberg University Hospital, Heidelberg, Germany
| | - Martin Irmler
- Institute of Experimental Genetics, Helmholtz Zentrum München, Neuherberg, Germany
| | - Christina Glantschnig
- Institute for Diabetes and Cancer (IDC); Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
- German Center for Diabetes Research (DZD), Neuherberg, Germany
- Joint Heidelberg-IDC Translational Diabetes Program, Inner Medicine 1, Heidelberg University Hospital, Heidelberg, Germany
| | - Manuel Gil-Lozano
- Institute for Diabetes and Cancer (IDC); Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
- German Center for Diabetes Research (DZD), Neuherberg, Germany
- Joint Heidelberg-IDC Translational Diabetes Program, Inner Medicine 1, Heidelberg University Hospital, Heidelberg, Germany
| | - Daniela Hass
- Institute for Diabetes and Cancer (IDC); Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
- German Center for Diabetes Research (DZD), Neuherberg, Germany
- Joint Heidelberg-IDC Translational Diabetes Program, Inner Medicine 1, Heidelberg University Hospital, Heidelberg, Germany
| | - Asrar Ali Khan
- Institute for Diabetes and Cancer (IDC); Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
- German Center for Diabetes Research (DZD), Neuherberg, Germany
- Joint Heidelberg-IDC Translational Diabetes Program, Inner Medicine 1, Heidelberg University Hospital, Heidelberg, Germany
| | - Marcos Rios Garcia
- Institute for Diabetes and Cancer (IDC); Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
- German Center for Diabetes Research (DZD), Neuherberg, Germany
- Joint Heidelberg-IDC Translational Diabetes Program, Inner Medicine 1, Heidelberg University Hospital, Heidelberg, Germany
| | - Frits Mattijssen
- Institute for Diabetes and Cancer (IDC); Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
- German Center for Diabetes Research (DZD), Neuherberg, Germany
- Joint Heidelberg-IDC Translational Diabetes Program, Inner Medicine 1, Heidelberg University Hospital, Heidelberg, Germany
| | - Adriano Maida
- Institute for Diabetes and Cancer (IDC); Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
- German Center for Diabetes Research (DZD), Neuherberg, Germany
- Joint Heidelberg-IDC Translational Diabetes Program, Inner Medicine 1, Heidelberg University Hospital, Heidelberg, Germany
| | - Daniel Tews
- Division of Pediatric Endocrinology and Diabetes, Department of Pediatrics and Adolescent Medicine, Ulm University Medical Center, Ulm, Germany
| | - Pamela Fischer-Posovszky
- Division of Pediatric Endocrinology and Diabetes, Department of Pediatrics and Adolescent Medicine, Ulm University Medical Center, Ulm, Germany
| | - Annette Feuchtinger
- Research Unit Analytical Pathology, Helmholtz Center Munich, Neuherberg, Germany
| | | | - Johannes Beckers
- German Center for Diabetes Research (DZD), Neuherberg, Germany
- Institute of Experimental Genetics, Helmholtz Zentrum München, Neuherberg, Germany
- Experimental Genetics, TUM School of Life Sciences, Technische Universität München, Freising, Germany
| | - Martin Wabitsch
- Division of Pediatric Endocrinology and Diabetes, Department of Pediatrics and Adolescent Medicine, Ulm University Medical Center, Ulm, Germany
| | - Henriette Uhlenhaut
- Institute for Diabetes and Cancer (IDC); Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
- Metabolic Programming, TUM School of Life Sciences Weihenstephan and ZIEL Institute for Food & Health, Munich, Germany
| | - Matthias Blüher
- Helmholtz Institute for Metabolic, Obesity and Vascular Research (HI-MAG) of the Helmholtz Zentrum München at the University of Leipzig and University Hospital Leipzig, Leipzig, Germany
| | - Jan Tuckermann
- Institute for Comparative Molecular Endocrinology, Universität Ulm, Ulm, Germany
| | - Marcel Scheideler
- Institute for Diabetes and Cancer (IDC); Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
- German Center for Diabetes Research (DZD), Neuherberg, Germany
- Joint Heidelberg-IDC Translational Diabetes Program, Inner Medicine 1, Heidelberg University Hospital, Heidelberg, Germany
| | - Alexander Bartelt
- Institute for Diabetes and Cancer (IDC); Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany.
- Institute for Cardiovascular Prevention (IPEK), Ludwig-Maximilians-University, Munich, Germany.
- German Center for Cardiovascular Research (DZHK), Partner Site Munich Heart Alliance, Munich, Germany.
- Department of Molecular Metabolism, Harvard T.H. Chan School of Public Health, Boston, MA, USA.
| | - Stephan Herzig
- Institute for Diabetes and Cancer (IDC); Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany.
- German Center for Diabetes Research (DZD), Neuherberg, Germany.
- Joint Heidelberg-IDC Translational Diabetes Program, Inner Medicine 1, Heidelberg University Hospital, Heidelberg, Germany.
- Molecular Metabolic Control, Medical Faculty, Technical University Munich, Munich, Germany.
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11
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Vettorazzi S, Nalbantoglu D, Gebhardt JCM, Tuckermann J. A guide to changing paradigms of glucocorticoid receptor function-a model system for genome regulation and physiology. FEBS J 2021; 289:5718-5743. [PMID: 34213830 DOI: 10.1111/febs.16100] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Revised: 06/08/2021] [Accepted: 07/01/2021] [Indexed: 12/13/2022]
Abstract
The glucocorticoid receptor (GR) is a bona fide ligand-regulated transcription factor. Cloned in the 80s, the GR has become one of the best-studied and clinically most relevant members of the nuclear receptor superfamily. Cooperative activity of GR with other transcription factors and a plethora of coregulators contribute to the tissue- and context-specific response toward the endogenous and pharmacological glucocorticoids (GCs). Furthermore, nontranscriptional activities in the cytoplasm are emerging as an additional function of GR. Over the past 40 years, the concepts of GR mechanisms of action had been constantly changing. Different methodologies in the pregenomic and genomic era of molecular biological research and recent cutting-edge technology in single-cell and single-molecule analysis are steadily evolving the views, how the GR in particular and transcriptional regulation in general act in physiological and pathological processes. In addition to the development of technologies for GR analysis, the use of model organisms provides insights how the GR in vivo executes GC action in tissue homeostasis, inflammation, and energy metabolism. The model organisms, namely the mouse, but also rats, zebrafish, and recently fruit flies carrying mutations of the GR became a major driving force to analyze the molecular function of GR in disease models. This guide provides an overview of the exciting research and paradigm shifts in the GR field from past to present with a focus on GR transcription factor networks, GR DNA-binding and single-cell analysis, and model systems.
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Affiliation(s)
- Sabine Vettorazzi
- Institute of Comparative Molecular Endocrinology (CME), Ulm University, Germany
| | - Denis Nalbantoglu
- Institute of Comparative Molecular Endocrinology (CME), Ulm University, Germany
| | | | - Jan Tuckermann
- Institute of Comparative Molecular Endocrinology (CME), Ulm University, Germany
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12
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Hachemi Y, Rapp AE, Lee S, Dorn AK, Krüger BT, Kaiser K, Ignatius A, Tuckermann J. Intact Glucocorticoid Receptor Dimerization Is Deleterious in Trauma-Induced Impaired Fracture Healing. Front Immunol 2021; 11:628287. [PMID: 33679723 PMCID: PMC7927427 DOI: 10.3389/fimmu.2020.628287] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Accepted: 12/29/2020] [Indexed: 11/13/2022] Open
Abstract
Following severe trauma, fracture healing is impaired because of overwhelming systemic and local inflammation. Glucocorticoids (GCs), acting via the glucocorticoid receptor (GR), influence fracture healing by modulating the trauma-induced immune response. GR dimerization-dependent gene regulation is essential for the anti-inflammatory effects of GCs. Therefore, we investigated in a murine trauma model of combined femur fracture and thoracic trauma, whether effective GR dimerization influences the pathomechanisms of trauma-induced compromised fracture healing. To this end, we used mice with decreased GR dimerization ability (GRdim). The healing process was analyzed by cytokine/chemokine multiplex analysis, flow cytometry, gene-expression analysis, histomorphometry, micro-computed tomography, and biomechanical testing. GRdim mice did not display a systemic or local hyper-inflammation upon combined fracture and thorax trauma. Strikingly, we discovered that GRdim mice were protected from fracture healing impairment induced by the additional thorax trauma. Collectively and in contrast to previous studies describing the beneficial effects of intact GR dimerization in inflammatory models, we report here an adverse role of intact GR dimerization in trauma-induced compromised fracture healing.
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Affiliation(s)
- Yasmine Hachemi
- Institute of Comparative Molecular Endocrinology, Ulm University, Ulm, Germany
| | - Anna E Rapp
- Institute of Orthopedic Research and Biomechanics, Ulm University Medical Center, Ulm, Germany
| | - Sooyeon Lee
- Institute of Comparative Molecular Endocrinology, Ulm University, Ulm, Germany
| | - Ann-Kristin Dorn
- Institute of Comparative Molecular Endocrinology, Ulm University, Ulm, Germany
| | - Benjamin T Krüger
- Institute of Orthopedic Research and Biomechanics, Ulm University Medical Center, Ulm, Germany
| | - Kathrin Kaiser
- Institute of Orthopedic Research and Biomechanics, Ulm University Medical Center, Ulm, Germany
| | - Anita Ignatius
- Institute of Orthopedic Research and Biomechanics, Ulm University Medical Center, Ulm, Germany
| | - Jan Tuckermann
- Institute of Comparative Molecular Endocrinology, Ulm University, Ulm, Germany
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13
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Lee S, Krüger BT, Ignatius A, Tuckermann J. Distinct Glucocorticoid Receptor Actions in Bone Homeostasis and Bone Diseases. Front Endocrinol (Lausanne) 2021; 12:815386. [PMID: 35082759 PMCID: PMC8784516 DOI: 10.3389/fendo.2021.815386] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Accepted: 12/16/2021] [Indexed: 12/29/2022] Open
Abstract
Glucocorticoids (GCs) are steroid hormones that respond to stress and the circadian rhythm. Pharmacological GCs are widely used to treat autoimmune and chronic inflammatory diseases despite their adverse effects on bone after long-term therapy. GCs regulate bone homeostasis in a cell-type specific manner, affecting osteoblasts, osteoclasts, and osteocytes. Endogenous physiological and exogenous/excessive GCs act via nuclear receptors, mainly via the GC receptor (GR). Endogenous GCs have anabolic effects on bone mass regulation, while excessive or exogenous GCs can cause detrimental effects on bone. GC-induced osteoporosis (GIO) is a common adverse effect after GC therapy, which increases the risk of fractures. Exogenous GC treatment impairs osteoblastogenesis, survival of the osteoblasts/osteocytes and prolongs the longevity of osteoclasts. Under normal physiological conditions, endogenous GCs are regulated by the circadian rhythm and circadian genes display oscillatory rhythmicity in bone cells. However, exogenous GCs treatment disturbs the circadian rhythm. Recent evidence suggests that the disturbed circadian rhythm by continuous exogenous GCs treatment can in itself hamper bone integrity. GC signaling is also important for fracture healing and rheumatoid arthritis, where crosstalk among several cell types including macrophages and stromal cells is indispensable. This review summarizes the complexity of GC actions via GR in bone cells at cellular and molecular levels, including the effect on circadian rhythmicity, and outlines new therapeutic possibilities for the treatment of their adverse effects.
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Affiliation(s)
- Sooyeon Lee
- Institute for Comparative Molecular Endocrinology, University of Ulm, Ulm, Germany
| | - Benjamin Thilo Krüger
- Institute of Orthopedic Research and Biomechanics, Trauma Research Center Ulm, Ulm University Medical Center, Ulm, Germany
| | - Anita Ignatius
- Institute of Orthopedic Research and Biomechanics, Trauma Research Center Ulm, Ulm University Medical Center, Ulm, Germany
| | - Jan Tuckermann
- Institute for Comparative Molecular Endocrinology, University of Ulm, Ulm, Germany
- *Correspondence: Jan Tuckermann,
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14
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Bao J, Zhuang Y, Chen Z, Cheng J, Zhong J. Detection of fatty acid composition of trabecular bone marrow by localized iDQC MRS at 3 T: A pilot study in healthy volunteers. Magn Reson Imaging 2020; 77:28-35. [PMID: 32926992 DOI: 10.1016/j.mri.2020.09.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 09/08/2020] [Accepted: 09/08/2020] [Indexed: 10/23/2022]
Abstract
BACKGROUND Although a growing body of research shows that the bone marrow adipose tissue (BMAT) may play an essential role in bone inflammation and energy metabolism, available noninvasive methods for distinguishing different fatty acids in BMAT are still limited, in spite of their potential to provide novel biomarkers for bone related diseases. PURPOSE To assess the ability of a localized intermolecular double quantum coherence (iDQC) spectroscopy sequence to resolve more fatty acid peaks than conventional MR spectroscopy (MRS), like polyunsaturated fatty acids (PUFA), from the human BMAT in the presence of trabecular bone; To preliminarily investigate whether the fatty acids composition is different between different regions and groups. RESULTS Compared with conventional MRS results, additional four fatty acids peaks were well resolved using the proposed method in human BMAT in the presence of trabecular bone. In addition, a different fat composition was found between distal femur and proximal tibia: fat was more unsaturated (vinyl, *p < 0.01; diallylic, *p < 0.01) in distal femur bone marrow than in proximal tibia, and this higher unsaturation level was caused by PUFA (r = 0.67, diallylic, *p < 0.01). No significant difference in fatty acid composition were found either between left and right legs, or between female and male in the healthy young subjects studied. CONCLUSION This study demonstrated that the unsaturated fatty acids information of human BMAT in the presence of trabecular bone can be clearly identified with the localized iDQC at 3 T. The resolved peaks, especially PUFA, may serve as additional diagnostic biomarkers for BMAT related diseases in the future.
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Affiliation(s)
- Jianfeng Bao
- Department of Magnetic Resonance Imaging, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou 450000, China
| | - Yuchuan Zhuang
- Department of Imaging Sciences, University of Rochester Medical Center, Rochester 14627, USA
| | - Zhong Chen
- Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance Research, Xiamen University, Xiamen 361000, China
| | - Jingliang Cheng
- Department of Magnetic Resonance Imaging, The First Affiliated Hospital of Zhengzhou University, Zhengzhou University, Zhengzhou 450000, China.
| | - Jianhui Zhong
- Department of Imaging Sciences, University of Rochester Medical Center, Rochester 14627, USA.
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15
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Bromodomain Protein BRD4 Accelerates Glucocorticoid Dysregulation of Bone Mass and Marrow Adiposis by Modulating H3K9 and Foxp1. Cells 2020; 9:cells9061500. [PMID: 32575577 PMCID: PMC7349708 DOI: 10.3390/cells9061500] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 06/11/2020] [Accepted: 06/16/2020] [Indexed: 12/11/2022] Open
Abstract
Glucocorticoid provokes bone mass loss and fatty marrow, accelerating osteoporosis development. Bromodomain protein BRD4, an acetyl–histone-binding chromatin reader, regulates stem cell and tissue homeostasis. We uncovered that glucocorticoid inhibited acetyl Lys-9 at the histone 3 (H3K9ac)-binding Runx2 promoter and decreased osteogenic differentiation, whereas bromodomain protein 4 (BRD4) and adipocyte formation were upregulated in bone-marrow mesenchymal progenitor cells. BRD4 knockdown improved H3K9ac occupation at the Runx2 promoter and osteogenesis, but attenuated glucocorticoid-mediated adipocyte formation together with the unaffected H3K9ac-binding PPARγ2 promoter. BRD4 regulated epigenome related to fatty acid metabolism and the forkhead box P1 (Foxp1) pathway, which occupied the PPARγ2 promoter to modulate glucocorticoid-induced adipocytic activity. In vivo, BRD4 inhibitor JQ-1 treatment mitigated methylprednisolone-induced suppression of bone mass, trabecular microstructure, mineral acquisition, and osteogenic differentiation. Foxp1 signaling, marrow fat, and adipocyte formation in glucocorticoid-treated skeleton were reversed upon JQ-1 treatment. Taken together, glucocorticoid-induced H3K9 hypoacetylation augmented BRD4 action to Foxp1, which steered mesenchymal progenitor cells toward adipocytes at the cost of osteogenic differentiation in osteoporotic skeletons. BRD4 inhibition slowed bone mass loss and marrow adiposity. Collective investigations convey a new epigenetic insight into acetyl histone reader BRD4 control of osteogenesis and adipogenesis in skeleton, and highlight the remedial effects of the BRD4 inhibitor on glucocorticoid-induced osteoporosis.
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Okada K, Okamoto T, Okumoto K, Takafuji Y, Ishida M, Kawao N, Matsuo O, Kaji H. PAI-1 is involved in delayed bone repair induced by glucocorticoids in mice. Bone 2020; 134:115310. [PMID: 32142912 DOI: 10.1016/j.bone.2020.115310] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Revised: 02/21/2020] [Accepted: 03/02/2020] [Indexed: 02/05/2023]
Abstract
Glucocorticoid (GC) treatments induce osteoporosis and chronic GC treatments have been suggested to induce delayed bone repair; however, the mechanisms by which GC induces delayed bone repair remain unclear. We herein investigated the roles of plasminogen activator inhibitor-1 (PAI-1) in GC-induced effects on bone repair after femoral bone injury using female mice with a PAI-1 deficiency and their wild-type counterparts. Dexamethasone (Dex) increased plasma PAI-1 levels as well as PAI-1 mRNA levels in the adipose tissues and muscles of wild-type mice. PAI-1 deficiency significantly blunted Dex-induced delayed bone repair in mice. Moreover, PAI-1 deficiency significantly blunted Runx2 mRNA levels suppressed by Dex as well as Dex-induced osteoblast apoptosis at the damaged site 7 days after bone injury in mice. On the other hand, PAI-1 deficiency did not affect adipogenic gene expression enhanced by Dex at the damaged site 7 days after bone injury in mice. In conclusion, we herein showed for the first time that PAI-1 is involved in delayed bone repair after bone injury induced by GC in mice. PAI-1 may influence early stage osteoblast differentiation and apoptosis during the osteoblastic restoration phase of the bone repair process.
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Affiliation(s)
- Kiyotaka Okada
- Department of Arts and Science, Kindai University Faculty of Medicine, Osaka-Sayama, Osaka 589-8511, Japan; Department of Physiology and Regenerative Medicine, Kindai University Faculty of Medicine, Osaka-Sayama, Osaka 589-8511, Japan
| | - Takahiro Okamoto
- Department of Physiology and Regenerative Medicine, Kindai University Faculty of Medicine, Osaka-Sayama, Osaka 589-8511, Japan
| | - Katsumi Okumoto
- Life Science Research Institute, Kindai University, Osaka-Sayama, Osaka 589-8511, Japan
| | - Yoshimasa Takafuji
- Department of Physiology and Regenerative Medicine, Kindai University Faculty of Medicine, Osaka-Sayama, Osaka 589-8511, Japan
| | - Masayoshi Ishida
- Department of Physiology and Regenerative Medicine, Kindai University Faculty of Medicine, Osaka-Sayama, Osaka 589-8511, Japan
| | - Naoyuki Kawao
- Department of Physiology and Regenerative Medicine, Kindai University Faculty of Medicine, Osaka-Sayama, Osaka 589-8511, Japan
| | - Osamu Matsuo
- Department of Physiology and Regenerative Medicine, Kindai University Faculty of Medicine, Osaka-Sayama, Osaka 589-8511, Japan
| | - Hiroshi Kaji
- Department of Physiology and Regenerative Medicine, Kindai University Faculty of Medicine, Osaka-Sayama, Osaka 589-8511, Japan.
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Rothe R, Schulze S, Neuber C, Hauser S, Rammelt S, Pietzsch J. Adjuvant drug-assisted bone healing: Part I – Modulation of inflammation. Clin Hemorheol Microcirc 2020; 73:381-408. [DOI: 10.3233/ch-199102] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Rebecca Rothe
- Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Institute of Radiopharmaceutical Cancer Research, Department of Radiopharmaceutical and Chemical Biology, Dresden, Germany
| | - Sabine Schulze
- University Center of Orthopaedics & Traumatology (OUC), University Hospital Carl Gustav Carus, Dresden, Germany
- Center for Translational Bone, Joint and Soft Tissue Research, University Hospital Carl Gustav Carus and Faculty of Medicine, Technische Universität Dresden, Dresden, Germany
| | - Christin Neuber
- Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Institute of Radiopharmaceutical Cancer Research, Department of Radiopharmaceutical and Chemical Biology, Dresden, Germany
| | - Sandra Hauser
- Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Institute of Radiopharmaceutical Cancer Research, Department of Radiopharmaceutical and Chemical Biology, Dresden, Germany
| | - Stefan Rammelt
- University Center of Orthopaedics & Traumatology (OUC), University Hospital Carl Gustav Carus, Dresden, Germany
- Center for Translational Bone, Joint and Soft Tissue Research, University Hospital Carl Gustav Carus and Faculty of Medicine, Technische Universität Dresden, Dresden, Germany
- Center for Regenerative Therapies Dresden (CRTD), Dresden, Germany
| | - Jens Pietzsch
- Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Institute of Radiopharmaceutical Cancer Research, Department of Radiopharmaceutical and Chemical Biology, Dresden, Germany
- Technische Universität Dresden, School of Science, Faculty of Chemistry and Food Chemistry, Dresden, Germany
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18
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Sharma AK, Shi X, Isales CM, McGee-Lawrence ME. Endogenous Glucocorticoid Signaling in the Regulation of Bone and Marrow Adiposity: Lessons from Metabolism and Cross Talk in Other Tissues. Curr Osteoporos Rep 2019; 17:438-445. [PMID: 31749087 DOI: 10.1007/s11914-019-00554-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
PURPOSE OF REVIEW The development of adiposity in the bone marrow, known as marrow adipose tissue (MAT), is often associated with musculoskeletal frailty. Glucocorticoids, which are a key component of the biological response to stress, affect both bone and MAT. These molecules signal through receptors such as the glucocorticoid receptor (GR), but the role of the GR in regulation of MAT is not yet clear from previous studies. The purpose of this review is to establish and determine the role of GR-mediated signaling in marrow adiposity by comparing and contrasting what is known against other energy-storing tissues like adipose tissue, liver, and muscle, to provide better insight into the regulation of MAT during times of metabolic stress (e.g., dietary challenges, aging). RECENT FINDINGS GR-mediated glucocorticoid signaling is critical for proper storage and utilization of lipids in cells such as adipocytes and hepatocytes and proteolysis in muscle, impacting whole-body composition, energy utilization, and homeostasis through a complex network of tissue cross talk between these systems. Loss of GR signaling in bone promotes increased MAT and decreased bone mass. GR-mediated signaling in the liver, adipose tissue, and muscle is critical for whole-body energy and metabolic homeostasis, and both similarities and differences in GR-mediated GC signaling in MAT as compared with these tissues are readily apparent. It is clear that GC-induced pathways work together through these tissues to affect systemic biology, and understanding the role of bone in these patterns of tissue cross talk may lead to a better understanding of MAT-bone biology that improves treatment strategies for frailty-associated diseases.
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Affiliation(s)
- Anuj K Sharma
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, 1460 Laney Walker Blvd., CB1101, Augusta, GA, USA
| | - Xingming Shi
- Department of Neuroscience and Regenerative Medicine, Augusta University, Augusta, GA, USA
| | - Carlos M Isales
- Department of Neuroscience and Regenerative Medicine, Augusta University, Augusta, GA, USA
- Department of Orthopaedic Surgery, Augusta University, Augusta, GA, USA
- Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, Augusta University, Augusta, GA, USA
| | - Meghan E McGee-Lawrence
- Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta University, 1460 Laney Walker Blvd., CB1101, Augusta, GA, USA.
- Department of Orthopaedic Surgery, Augusta University, Augusta, GA, USA.
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19
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Ahmad M, Hachemi Y, Paxian K, Mengele F, Koenen M, Tuckermann J. A Jack of All Trades: Impact of Glucocorticoids on Cellular Cross-Talk in Osteoimmunology. Front Immunol 2019; 10:2460. [PMID: 31681333 PMCID: PMC6811614 DOI: 10.3389/fimmu.2019.02460] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Accepted: 10/02/2019] [Indexed: 12/13/2022] Open
Abstract
Glucocorticoids (GCs) are known to have a strong impact on the immune system, metabolism, and bone homeostasis. While these functions have been long investigated separately in immunology, metabolism, or bone biology, the understanding of how GCs regulate the cellular cross-talk between innate immune cells, mesenchymal cells, and other stromal cells has been garnering attention rather recently. Here we review the recent findings of GC action in osteoporosis, inflammatory bone diseases (rheumatoid and osteoarthritis), and bone regeneration during fracture healing. We focus on studies of pre-clinical animal models that enable dissecting the role of GC actions in innate immune cells, stromal cells, and bone cells using conditional and function-selective mutant mice of the GC receptor (GR), or mice with impaired GC signaling. Importantly, GCs do not only directly affect cellular functions, but also influence the cross-talk between mesenchymal and immune cells, contributing to both beneficial and adverse effects of GCs. Given the importance of endogenous GCs as stress hormones and the wide prescription of pharmaceutical GCs, an improved understanding of GC action is decisive for tackling inflammatory bone diseases, osteoporosis, and aging.
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Affiliation(s)
- Mubashir Ahmad
- Institute of Comparative Molecular Endocrinology (CME), University of Ulm, Ulm, Germany
| | - Yasmine Hachemi
- Institute of Comparative Molecular Endocrinology (CME), University of Ulm, Ulm, Germany
| | - Kevin Paxian
- Institute of Comparative Molecular Endocrinology (CME), University of Ulm, Ulm, Germany
| | - Florian Mengele
- Institute of Comparative Molecular Endocrinology (CME), University of Ulm, Ulm, Germany
- Praxisklinik für Orthopädie, Unfall- und Neurochirurgie Prof. Bischoff/ Dr. Spies/ Dr. Mengele, Neu-Ulm, Germany
| | - Mascha Koenen
- Institute of Comparative Molecular Endocrinology (CME), University of Ulm, Ulm, Germany
- Department of Immunobiology, Yale School of Medicine, New Haven, CT, United States
| | - Jan Tuckermann
- Institute of Comparative Molecular Endocrinology (CME), University of Ulm, Ulm, Germany
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20
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Escoter-Torres L, Caratti G, Mechtidou A, Tuckermann J, Uhlenhaut NH, Vettorazzi S. Fighting the Fire: Mechanisms of Inflammatory Gene Regulation by the Glucocorticoid Receptor. Front Immunol 2019; 10:1859. [PMID: 31440248 PMCID: PMC6693390 DOI: 10.3389/fimmu.2019.01859] [Citation(s) in RCA: 77] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Accepted: 07/23/2019] [Indexed: 12/12/2022] Open
Abstract
For many decades, glucocorticoids have been widely used as the gold standard treatment for inflammatory conditions. Unfortunately, their clinical use is limited by severe adverse effects such as insulin resistance, cardiometabolic diseases, muscle and skin atrophies, osteoporosis, and depression. Glucocorticoids exert their effects by binding to the Glucocorticoid Receptor (GR), a ligand-activated transcription factor which both positively, and negatively regulates gene expression. Extensive research during the past several years has uncovered novel mechanisms by which the GR activates and represses its target genes. Genome-wide studies and mouse models have provided valuable insight into the molecular mechanisms of inflammatory gene regulation by GR. This review focusses on newly identified target genes and GR co-regulators that are important for its anti-inflammatory effects in innate immune cells, as well as mutations within the GR itself that shed light on its transcriptional activity. This research progress will hopefully serve as the basis for the development of safer immune suppressants with reduced side effect profiles.
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Affiliation(s)
- Laura Escoter-Torres
- Molecular Endocrinology, Helmholtz Zentrum München (HMGU), German Center for Diabetes Research (DZD), Institute for Diabetes and Cancer IDC, Munich, Germany
| | - Giorgio Caratti
- Department of Biology, Institute for Comparative Molecular Endocrinology, University of Ulm, Ulm, Germany
| | - Aikaterini Mechtidou
- Molecular Endocrinology, Helmholtz Zentrum München (HMGU), German Center for Diabetes Research (DZD), Institute for Diabetes and Cancer IDC, Munich, Germany
| | - Jan Tuckermann
- Department of Biology, Institute for Comparative Molecular Endocrinology, University of Ulm, Ulm, Germany
| | - Nina Henriette Uhlenhaut
- Molecular Endocrinology, Helmholtz Zentrum München (HMGU), German Center for Diabetes Research (DZD), Institute for Diabetes and Cancer IDC, Munich, Germany.,Gene Center, Ludwig-Maximilians-Universität (LMU), Munich, Germany
| | - Sabine Vettorazzi
- Department of Biology, Institute for Comparative Molecular Endocrinology, University of Ulm, Ulm, Germany
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21
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Treatment with synthetic glucocorticoid impairs bone metabolism, as revealed by in vivo imaging of osteoblasts and osteoclasts in medaka fish. Biomed Pharmacother 2019; 118:109101. [PMID: 31315073 DOI: 10.1016/j.biopha.2019.109101] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Revised: 06/04/2019] [Accepted: 06/06/2019] [Indexed: 01/28/2023] Open
Abstract
Glucocorticoids (GCs) play an important role in the stress reaction and function in the development of multiple tissues in our body. When given chronically in supraphysiologic doses, GCs are associated with orthodontic tooth movement, with serious side effects and particularly adverse effects on bone metabolism. However, the effects of steroids on bone cell dynamics are incompletely understood. Therefore, in this present study we examined the participation of osteoblasts and osteoclasts in osterix-DsRed/TRAP-EGFP double transgenic (Tg) medaka treated with synthetic GCs. Chronic continuous administration of prednisolone (PN) significantly reduced the fluorescence signals in the whole body of both osterix-DsRed and TRAP-EGFP medaka at 18 days, and those of the pharyngeal bone and tooth region at 32 days. To examine the capacity of the medaka for fracture healing during chronic administration of PN, we caused a fracture of a part of the bony fin ray at 18 days after the initiation of PN continuous administration. The bone fracture healing was significantly delayed by 32 days, accompanied by decreased signal area of both osterix-DsRed and TRAP-EGFP compared with that of the control. Next, to investigate the effect of acute administration of GC on the fracture healing, we started administration of dexamethasone (DX) immediately after the bone fracture, and this administration lasted during the 11 days of fracture healing. The results showed that the TRAP-EGFP-positive osteoclasts were reduced in area, but not the osterix-DsRed-positive osteoblasts. Lastly, to confirm the function of the glucocorticoid receptor in bone healing, we generated glucocorticoid receptor 2-deficient medaka (gr2-/-). The fluorescent signal area of osterix-DsRed and TRAP-EGFP were increased at bone fracture sites in these fish, and DX treatment of them decreased the TRAP-EGFP signal area compared with that for the control fish. Our results indicate that GRs negatively regulated osteoclast recruitment and the accumulation of osteoblasts in bone fracture healing.
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22
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Hachemi Y, Rapp AE, Picke AK, Weidinger G, Ignatius A, Tuckermann J. Molecular mechanisms of glucocorticoids on skeleton and bone regeneration after fracture. J Mol Endocrinol 2018; 61:R75-R90. [PMID: 29588427 PMCID: PMC5976078 DOI: 10.1530/jme-18-0024] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Accepted: 03/27/2018] [Indexed: 12/29/2022]
Abstract
Glucocorticoid hormones (GCs) have profound effects on bone metabolism. Via their nuclear hormone receptor - the GR - they act locally within bone cells and modulate their proliferation, differentiation, and cell death. Consequently, high glucocorticoid levels - as present during steroid therapy or stress - impair bone growth and integrity, leading to retarded growth and glucocorticoid-induced osteoporosis, respectively. Because of their profound impact on the immune system and bone cell differentiation, GCs also affect bone regeneration and fracture healing. The use of conditional-mutant mouse strains in recent research provided insights into the cell-type-specific actions of the GR. However, despite recent advances in system biology approaches addressing GR genomics in general, little is still known about the molecular mechanisms of GCs and GR in bone cells. Here, we review the most recent findings on the molecular mechanisms of the GR in general and the known cell-type-specific actions of the GR in mesenchymal cells and their derivatives as well as in osteoclasts during bone homeostasis, GC excess, bone regeneration and fracture healing.
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Affiliation(s)
- Yasmine Hachemi
- Institute of Comparative Molecular EndocrinologyUlm University, Ulm, Germany
| | - Anna E Rapp
- Institute of Orthopaedic Research and BiomechanicsUlm University Medical Centre, Ulm, Germany
| | - Ann-Kristin Picke
- Institute of Comparative Molecular EndocrinologyUlm University, Ulm, Germany
| | - Gilbert Weidinger
- Institute of Biochemistry and Molecular BiologyUlm University, Ulm, Germany
| | - Anita Ignatius
- Institute of Orthopaedic Research and BiomechanicsUlm University Medical Centre, Ulm, Germany
| | - Jan Tuckermann
- Institute of Comparative Molecular EndocrinologyUlm University, Ulm, Germany
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