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Root SH, Matthews BG, Torreggiani E, Aguila HL, Kalajzic I. Hematopoietic and stromal DMP1-Cre labeled cells form a unique niche in the bone marrow. Sci Rep 2023; 13:22403. [PMID: 38104230 PMCID: PMC10725438 DOI: 10.1038/s41598-023-49713-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2023] [Accepted: 12/11/2023] [Indexed: 12/19/2023] Open
Abstract
Skeletogenesis and hematopoiesis are interdependent. Niches form between cells of both lineages where microenvironmental cues support specific lineage commitment. Because of the complex topography of bone marrow (BM), the identity and function of cells within specialized niches has not been fully elucidated. Dentin Matrix Protein 1 (DMP1)-Cre mice have been utilized in bone studies as mature osteoblasts and osteocytes express DMP1. DMP1 has been identified in CXCL12+ cells and an undefined CD45+ population. We crossed DMP1-Cre with Ai9 reporter mice and analyzed the tdTomato+ (tdT+) population in BM and secondary hematopoietic organs. CD45+tdT+ express myeloid markers including CD11b and are established early in ontogeny. CD45+tdT+ cells phagocytose, respond to LPS and are radioresistant. Depletion of macrophages caused a significant decrease in tdT+CD11b+ myeloid populations. A subset of CD45+tdT+ cells may be erythroid island macrophages (EIM) which are depleted after G-CSF treatment. tdT+CXCL12+ cells are in direct contact with F4/80 macrophages, express RANKL and form a niche with B220+ B cells. A population of resident cells within the thymus are tdT+ and express myeloid markers and RANKL. In conclusion, in addition to targeting osteoblast/osteocytes, DMP1-Cre labels unique cell populations of macrophage and stromal cells within BM and thymus niches and expresses key microenvironmental factors.
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Affiliation(s)
- Sierra H Root
- Center for Regenerative Medicine and Skeletal Development, MC 3705, School of Dental Medicine, UConn Health, 263 Farmington Ave, Farmington, CT, 06030, USA.
- Division of Pediatric Dentistry, MC1610, School of Dental Medicine, UConn Health, 263 Farmington Ave, Farmington, CT, 06030, USA.
| | - Brya G Matthews
- Center for Regenerative Medicine and Skeletal Development, MC 3705, School of Dental Medicine, UConn Health, 263 Farmington Ave, Farmington, CT, 06030, USA
- Department of Molecular Medicine and Pathology, University of Auckland, Auckland, New Zealand
| | - Elena Torreggiani
- Center for Regenerative Medicine and Skeletal Development, MC 3705, School of Dental Medicine, UConn Health, 263 Farmington Ave, Farmington, CT, 06030, USA
| | | | - Ivo Kalajzic
- Center for Regenerative Medicine and Skeletal Development, MC 3705, School of Dental Medicine, UConn Health, 263 Farmington Ave, Farmington, CT, 06030, USA.
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2
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Marahleh A, Kitaura H, Ohori F, Noguchi T, Mizoguchi I. The osteocyte and its osteoclastogenic potential. Front Endocrinol (Lausanne) 2023; 14:1121727. [PMID: 37293482 PMCID: PMC10244721 DOI: 10.3389/fendo.2023.1121727] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Accepted: 04/07/2023] [Indexed: 06/10/2023] Open
Abstract
The skeleton is an organ of dual functionality; on the one hand, it provides protection and structural competence. On the other hand, it participates extensively in coordinating homeostasis globally given that it is a mineral and hormonal reservoir. Bone is the only tissue in the body that goes through strategically consistent bouts of bone resorption to ensure its integrity and organismal survival in a temporally and spatially coordinated process, known as bone remodeling. Bone remodeling is directly enacted by three skeletal cell types, osteoclasts, osteoblasts, and osteocytes; these cells represent the acting force in a basic multicellular unit and ensure bone health maintenance. The osteocyte is an excellent mechanosensory cell and has been positioned as the choreographer of bone remodeling. It is, therefore, not surprising that a holistic grasp of the osteocyte entity in the bone is warranted. This review discusses osteocytogenesis and associated molecular and morphological changes and describes the osteocytic lacunocanalicular network (LCN) and its organization. We highlight new knowledge obtained from transcriptomic analyses of osteocytes and discuss the regulatory role of osteocytes in promoting osteoclastogenesis with an emphasis on the case of osteoclastogenesis in anosteocytic bones. We arrive at the conclusion that osteocytes exhibit several redundant means through which osteoclast formation can be initiated. However, whether osteocytes are true "orchestrators of bone remodeling" cannot be verified from the animal models used to study osteocyte biology in vivo. Results from studying osteocyte biology using current animal models should come with the caveat that these models are not osteocyte-specific, and conclusions from these studies should be interpreted cautiously.
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Affiliation(s)
- Aseel Marahleh
- Frontier Research Institute for Interdisciplinary Sciences (FRIS), Tohoku University, Sendai, Japan
- Division of Orthodontics and Dentofacial Orthopedics, Graduate School of Dentistry, Tohoku University, Sendai, Japan
| | - Hideki Kitaura
- Division of Orthodontics and Dentofacial Orthopedics, Graduate School of Dentistry, Tohoku University, Sendai, Japan
| | - Fumitoshi Ohori
- Division of Orthodontics and Dentofacial Orthopedics, Graduate School of Dentistry, Tohoku University, Sendai, Japan
| | - Takahiro Noguchi
- Division of Orthodontics and Dentofacial Orthopedics, Graduate School of Dentistry, Tohoku University, Sendai, Japan
| | - Itaru Mizoguchi
- Division of Orthodontics and Dentofacial Orthopedics, Graduate School of Dentistry, Tohoku University, Sendai, Japan
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3
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Leale DM, Li L, Settles M, Mitchell K, Froenicke L, Yik JH, Haudenschild DR. A two-stage digestion of whole murine knee joints for single-cell RNA sequencing. OSTEOARTHRITIS AND CARTILAGE OPEN 2022; 4:100321. [DOI: 10.1016/j.ocarto.2022.100321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Revised: 11/03/2022] [Accepted: 11/07/2022] [Indexed: 11/25/2022] Open
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4
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Protein tyrosine phosphatases in skeletal development and diseases. Bone Res 2022; 10:10. [PMID: 35091552 PMCID: PMC8799702 DOI: 10.1038/s41413-021-00181-x] [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: 03/30/2021] [Revised: 07/29/2021] [Accepted: 09/14/2021] [Indexed: 12/24/2022] Open
Abstract
Skeletal development and homeostasis in mammals are modulated by finely coordinated processes of migration, proliferation, differentiation, and death of skeletogenic cells originating from the mesoderm and neural crest. Numerous molecular mechanisms are involved in these regulatory processes, one of which is protein posttranslational modifications, particularly protein tyrosine phosphorylation (PYP). PYP occurs mainly through the action of protein tyrosine kinases (PTKs), modifying protein enzymatic activity, changing its cellular localization, and aiding in the assembly or disassembly of protein signaling complexes. Under physiological conditions, PYP is balanced by the coordinated action of PTKs and protein tyrosine phosphatases (PTPs). Dysregulation of PYP can cause genetic, metabolic, developmental, and oncogenic skeletal diseases. Although PYP is a reversible biochemical process, in contrast to PTKs, little is known about how this equilibrium is modulated by PTPs in the skeletal system. Whole-genome sequencing has revealed a large and diverse superfamily of PTP genes (over 100 members) in humans, which can be further divided into cysteine (Cys)-, aspartic acid (Asp)-, and histidine (His)-based PTPs. Here, we review current knowledge about the functions and regulatory mechanisms of 28 PTPs involved in skeletal development and diseases; 27 of them belong to class I and II Cys-based PTPs, and the other is an Asp-based PTP. Recent progress in analyzing animal models that harbor various mutations in these PTPs and future research directions are also discussed. Our literature review indicates that PTPs are as crucial as PTKs in supporting skeletal development and homeostasis.
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5
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Wee NK, Sims NA, Morello R. The Osteocyte Transcriptome: Discovering Messages Buried Within Bone. Curr Osteoporos Rep 2021; 19:604-615. [PMID: 34757588 PMCID: PMC8720072 DOI: 10.1007/s11914-021-00708-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 09/24/2021] [Indexed: 12/16/2022]
Abstract
PURPOSE OF THE REVIEW Osteocytes are cells embedded within the bone matrix, but their function and specific patterns of gene expression remain only partially defined; this is beginning to change with recent studies using transcriptomics. This unbiased approach can generate large amounts of data and is now being used to identify novel genes and signalling pathways within osteocytes both at baseline conditions and in response to stimuli. This review outlines the methods used to isolate cell populations containing osteocytes, and key recent transcriptomic studies that used osteocyte-containing preparations from bone tissue. RECENT FINDINGS Three common methods are used to prepare samples to examine osteocyte gene expression: digestion followed by sorting, laser capture microscopy, and the isolation of cortical bone shafts. All these methods present challenges in interpreting the data generated. Genes previously not known to be expressed by osteocytes have been identified and variations in osteocyte gene expression have been reported with age, sex, anatomical location, mechanical loading, and defects in bone strength. A substantial proportion of newly identified transcripts in osteocytes remain functionally undefined but several have been cross-referenced with functional data. Future work and improved methods (e.g. scRNAseq) likely provide useful resources for the study of osteocytes and important new information on the identity and functions of this unique cell type within the skeleton.
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Affiliation(s)
- Natalie Ky Wee
- Bone Cell Biology and Disease Unit, St Vincent's Institute of Medical Research, 9 Princes St, Fitzroy, 3065, Australia
| | - Natalie A Sims
- Bone Cell Biology and Disease Unit, St Vincent's Institute of Medical Research, 9 Princes St, Fitzroy, 3065, Australia
- Department of Medicine, The University of Melbourne, St. Vincent's Hospital, Melbourne, 3065, Australia
| | - Roy Morello
- Department of Physiology & Cell Biology, University of Arkansas for Medical Sciences, Little Rock, AR, USA.
- Department of Orthopaedic Surgery, University of Arkansas for Medical Sciences, Little Rock, AR, USA.
- Division of Genetics, University of Arkansas for Medical Sciences, Little Rock, AR, USA.
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6
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Wang Z, Li X, Yang J, Gong Y, Zhang H, Qiu X, Liu Y, Zhou C, Chen Y, Greenbaum J, Cheng L, Hu Y, Xie J, Yang X, Li Y, Schiller MR, Chen Y, Tan L, Tang SY, Shen H, Xiao HM, Deng HW. Single-cell RNA sequencing deconvolutes the in vivo heterogeneity of human bone marrow-derived mesenchymal stem cells. Int J Biol Sci 2021; 17:4192-4206. [PMID: 34803492 PMCID: PMC8579438 DOI: 10.7150/ijbs.61950] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Accepted: 09/20/2021] [Indexed: 02/07/2023] Open
Abstract
Bone marrow-derived mesenchymal stem cells (BM-MSCs) are multipotent stromal cells that have a critical role in the maintenance of skeletal tissues such as bone, cartilage, and the fat in bone marrow. In addition to providing microenvironmental support for hematopoietic processes, BM-MSCs can differentiate into various mesodermal lineages including osteoblast/osteocyte, chondrocyte, and adipocyte that are crucial for bone metabolism. While BM-MSCs have high cell-to-cell heterogeneity in gene expression, the cell subtypes that contribute to this heterogeneity in vivo in humans have not been characterized. To investigate the transcriptional diversity of BM-MSCs, we applied single-cell RNA sequencing (scRNA-seq) on freshly isolated CD271+ BM-derived mononuclear cells (BM-MNCs) from two human subjects. We successfully identified LEPRhiCD45low BM-MSCs within the CD271+ BM-MNC population, and further codified the BM-MSCs into distinct subpopulations corresponding to the osteogenic, chondrogenic, and adipogenic differentiation trajectories, as well as terminal-stage quiescent cells. Biological functional annotations of the transcriptomes suggest that osteoblast precursors induce angiogenesis coupled with osteogenesis, and chondrocyte precursors have the potential to differentiate into myocytes. We also discovered transcripts for several clusters of differentiation (CD) markers that were either highly expressed (e.g., CD167b, CD91, CD130 and CD118) or absent (e.g., CD74, CD217, CD148 and CD68) in BM-MSCs, representing potential novel markers for human BM-MSC purification. This study is the first systematic in vivo dissection of human BM-MSCs cell subtypes at the single-cell resolution, revealing an insight into the extent of their cellular heterogeneity and roles in maintaining bone homeostasis.
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Affiliation(s)
- Zun Wang
- Xiangya School of Nursing, Central South University, Changsha, 410013, China; Laboratory of Molecular and Statistical Genetics, College of Life Sciences, Human Normal University, Changsha, 410081, China
- Tulane Center for Biomedical Informatics and Genomics, School of Medicine, Tulane University, New Orleans, 70112, USA
| | - Xiaohua Li
- Xiangya School of Nursing, Central South University, Changsha, 410013, China; Laboratory of Molecular and Statistical Genetics, College of Life Sciences, Human Normal University, Changsha, 410081, China
| | - Junxiao Yang
- Department of Orthopedics, Xiangya Hospital, Central South University, Changsha, 410008, China
| | - Yun Gong
- Tulane Center for Biomedical Informatics and Genomics, School of Medicine, Tulane University, New Orleans, 70112, USA
| | - Huixi Zhang
- Laboratory of Molecular and Statistical Genetics, College of Life Sciences, Human Normal University, Changsha, 410081, China
| | - Xiang Qiu
- School of Basic Medical Science, Central South University, Changsha, 410008, China
| | - Ying Liu
- Laboratory of Molecular and Statistical Genetics, College of Life Sciences, Human Normal University, Changsha, 410081, China
| | - Cui Zhou
- Laboratory of Molecular and Statistical Genetics, College of Life Sciences, Human Normal University, Changsha, 410081, China
| | - Yu Chen
- Laboratory of Molecular and Statistical Genetics, College of Life Sciences, Human Normal University, Changsha, 410081, China
| | - Jonathan Greenbaum
- Tulane Center for Biomedical Informatics and Genomics, School of Medicine, Tulane University, New Orleans, 70112, USA
| | - Liang Cheng
- Department of Orthopedics and National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, 410008, China
| | - Yihe Hu
- Department of Orthopedics, Xiangya Hospital, Central South University, Changsha, 410008, China
| | - Jie Xie
- Department of Orthopedics, Xiangya Hospital, Central South University, Changsha, 410008, China
| | - Xucheng Yang
- Department of Orthopedics, Xiangya Hospital, Central South University, Changsha, 410008, China
| | - Yusheng Li
- Department of Orthopedics, Xiangya Hospital, Central South University, Changsha, 410008, China
| | - Martin R. Schiller
- Nevada Institute of Personalized Medicine and School of Life Science, 4505 S. Maryland Pkwy, Las Vegas, NV 89154-4004, USA
| | - Yiping Chen
- Department of Cell and Molecular Biology, School of Science and Engineering, Tulane University, New Orleans, LA 70112, USA
| | - Lijun Tan
- Laboratory of Molecular and Statistical Genetics, College of Life Sciences, Human Normal University, Changsha, 410081, China
| | - Si-Yuan Tang
- Xiangya School of Nursing, Central South University, Changsha, 410013, China; Laboratory of Molecular and Statistical Genetics, College of Life Sciences, Human Normal University, Changsha, 410081, China
- Hunan Women's Research Association, Changsha, 410011, China
| | - Hui Shen
- Tulane Center for Biomedical Informatics and Genomics, School of Medicine, Tulane University, New Orleans, 70112, USA
| | - Hong-Mei Xiao
- School of Basic Medical Science, Central South University, Changsha, 410008, China
- Center of Reproductive Health, System Biology and Data Information, Institute of Reproductive & Stem Cell Engineering, School of Basic Medical Science, Central South University, Changsha, 410008, China
| | - Hong-Wen Deng
- Tulane Center for Biomedical Informatics and Genomics, School of Medicine, Tulane University, New Orleans, 70112, USA
- School of Basic Medical Science, Central South University, Changsha, 410008, China
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7
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Isojima T, Sims NA. Cortical bone development, maintenance and porosity: genetic alterations in humans and mice influencing chondrocytes, osteoclasts, osteoblasts and osteocytes. Cell Mol Life Sci 2021; 78:5755-5773. [PMID: 34196732 PMCID: PMC11073036 DOI: 10.1007/s00018-021-03884-w] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 06/06/2021] [Accepted: 06/21/2021] [Indexed: 12/13/2022]
Abstract
Cortical bone structure is a crucial determinant of bone strength, yet for many years studies of novel genes and cell signalling pathways regulating bone strength have focused on the control of trabecular bone mass. Here we focus on mechanisms responsible for cortical bone development, growth, and degeneration, and describe some recently described genetic-driven modifications in humans and mice that reveal how these processes may be controlled. We start with embryonic osteogenesis of preliminary bone structures preceding the cortex and describe how this structure consolidates then matures to a dense, vascularised cortex containing an increasing proportion of lamellar bone. These processes include modelling-induced, and load-dependent, asymmetric cortical expansion, which enables the cortex's transition from a highly porous woven structure to a consolidated and thickened highly mineralised lamellar bone structure, infiltrated by vascular channels. Sex-specific differences emerge during this process. With aging, the process of consolidation reverses: cortical pores enlarge, leading to greater cortical porosity, trabecularisation and loss of bone strength. Each process requires co-ordination between bone formation, bone mineralisation, vascularisation, and bone resorption, with a need for locational-, spatial- and cell-specific signalling pathways to mediate this co-ordination. We will discuss these processes, and a number of cell-signalling pathways identified in both murine and human genetic studies to regulate cortical bone mass, including signalling through gp130, STAT3, PTHR1, WNT16, NOTCH, NOTUM and sFRP4.
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Affiliation(s)
- Tsuyoshi Isojima
- St. Vincent's Institute of Medical Research, 9 Princes St, Fitzroy, VIC, 3122, Australia
- Department of Pediatrics, Teikyo University School of Medicine, Tokyo, Japan
| | - Natalie A Sims
- St. Vincent's Institute of Medical Research, 9 Princes St, Fitzroy, VIC, 3122, Australia.
- Department of Medicine at St. Vincent's Hospital, The University of Melbourne, Fitzroy, VIC, Australia.
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8
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Qiu X, Liu Y, Shen H, Wang Z, Gong Y, Yang J, Li X, Zhang H, Chen Y, Zhou C, Lv W, Cheng L, Hu Y, Li B, Shen W, Zhu X, Tan LJ, Xiao HM, Deng HW. Single-cell RNA sequencing of human femoral head in vivo. Aging (Albany NY) 2021; 13:15595-15619. [PMID: 34111027 PMCID: PMC8221309 DOI: 10.18632/aging.203124] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Accepted: 05/13/2021] [Indexed: 11/25/2022]
Abstract
The homeostasis of bone metabolism depends on the coupling and precise regulation of various types of cells in bone tissue. However, the communication and interaction between bone tissue cells at the single-cell level remains poorly understood. Thus, we performed single-cell RNA sequencing (scRNA-seq) on the primary human femoral head tissue cells (FHTCs). Nine cell types were identified in 26,574 primary human FHTCs, including granulocytes, T cells, monocytes, B cells, red blood cells, osteoblastic lineage cells, endothelial cells, endothelial progenitor cells (EPCs) and plasmacytoid dendritic cells. We identified serine protease 23 (PRSS23) and matrix remodeling associated protein 8 (MXRA8) as novel bone metabolism-related genes. Additionally, we found that several subtypes of monocytes, T cells and B cells were related to bone metabolism. Cell-cell communication analysis showed that collagen, chemokine, transforming growth factor and their ligands have significant roles in the crosstalks between FHTCs. In particular, EPCs communicated with osteoblastic lineage cells closely via the "COL2A1-ITGB1" interaction pair. Collectively, this study provided an initial characterization of the cellular composition of the human FHTCs and the complex crosstalks between them at the single-cell level. It is a unique starting resource for in-depth insights into bone metabolism.
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Affiliation(s)
- Xiang Qiu
- Center for System Biology, Data Sciences, and Reproductive Health, School of Basic Medical Science, Central South University, Yuelu, Changsha 410013, China
| | - Ying Liu
- Laboratory of Molecular and Statistical Genetics, College of Life Sciences, Human Normal University, Changsha 410081, China
| | - Hui Shen
- Tulane Center of Biomedical Informatics and Genomics, Deming Department of Medicine, School of Medicine, Tulane University, New Orleans, LA 70112, USA
| | - Zun Wang
- Xiangya Nursing School, Central South University, Changsha 410013, China
| | - Yun Gong
- Tulane Center of Biomedical Informatics and Genomics, Deming Department of Medicine, School of Medicine, Tulane University, New Orleans, LA 70112, USA
| | - Junxiao Yang
- Department of Orthopedics, Xiangya Hospital, Central South University, Changsha 410008, China
| | - Xiaohua Li
- Laboratory of Molecular and Statistical Genetics, College of Life Sciences, Human Normal University, Changsha 410081, China
| | - Huixi Zhang
- Laboratory of Molecular and Statistical Genetics, College of Life Sciences, Human Normal University, Changsha 410081, China
| | - Yu Chen
- Laboratory of Molecular and Statistical Genetics, College of Life Sciences, Human Normal University, Changsha 410081, China
| | - Cui Zhou
- Laboratory of Molecular and Statistical Genetics, College of Life Sciences, Human Normal University, Changsha 410081, China
| | - Wanqiang Lv
- Center for System Biology, Data Sciences, and Reproductive Health, School of Basic Medical Science, Central South University, Yuelu, Changsha 410013, China
| | - Liang Cheng
- Department of Orthopedics and National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha 410008, China
| | - Yihe Hu
- Department of Orthopedics, Xiangya Hospital, Central South University, Changsha 410008, China
| | - Boyang Li
- Center for System Biology, Data Sciences, and Reproductive Health, School of Basic Medical Science, Central South University, Yuelu, Changsha 410013, China
| | - Wendi Shen
- Center for System Biology, Data Sciences, and Reproductive Health, School of Basic Medical Science, Central South University, Yuelu, Changsha 410013, China
| | - Xuezhen Zhu
- Center for System Biology, Data Sciences, and Reproductive Health, School of Basic Medical Science, Central South University, Yuelu, Changsha 410013, China
| | - Li-Jun Tan
- Laboratory of Molecular and Statistical Genetics, College of Life Sciences, Human Normal University, Changsha 410081, China
| | - Hong-Mei Xiao
- Center for System Biology, Data Sciences, and Reproductive Health, School of Basic Medical Science, Central South University, Yuelu, Changsha 410013, China
| | - Hong-Wen Deng
- Center for System Biology, Data Sciences, and Reproductive Health, School of Basic Medical Science, Central South University, Yuelu, Changsha 410013, China
- Tulane Center of Biomedical Informatics and Genomics, Deming Department of Medicine, School of Medicine, Tulane University, New Orleans, LA 70112, USA
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9
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Walker EC, Truong K, McGregor NE, Poulton IJ, Isojima T, Gooi JH, Martin TJ, Sims NA. Cortical bone maturation in mice requires SOCS3 suppression of gp130/STAT3 signalling in osteocytes. eLife 2020; 9:e56666. [PMID: 32458800 PMCID: PMC7253175 DOI: 10.7554/elife.56666] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Accepted: 05/01/2020] [Indexed: 12/23/2022] Open
Abstract
Bone strength is determined by its dense cortical shell, generated by unknown mechanisms. Here we use the Dmp1Cre:Socs3f/f mouse, with delayed cortical bone consolidation, to characterise cortical maturation and identify control signals. We show that cortical maturation requires a reduction in cortical porosity, and a transition from low to high density bone, which continues even after cortical shape is established. Both processes were delayed in Dmp1Cre:Socs3f/f mice. SOCS3 (suppressor of cytokine signalling 3) inhibits signalling by leptin, G-CSF, and IL-6 family cytokines (gp130). In Dmp1Cre:Socs3f/f bone, STAT3 phosphorylation was prolonged in response to gp130-signalling cytokines, but not G-CSF or leptin. Deletion of gp130 in Dmp1Cre:Socs3f/f mice suppressed STAT3 phosphorylation in osteocytes and osteoclastic resorption within cortical bone, leading to rescue of the corticalisation defect, and restoration of compromised bone strength. We conclude that cortical bone development includes both pore closure and accumulation of high density bone, and that these processes require suppression of gp130-STAT3 signalling in osteocytes.
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Affiliation(s)
- Emma C Walker
- St. Vincent’s Institute of Medical ResearchFitzroyAustralia
| | - Kim Truong
- St. Vincent’s Institute of Medical ResearchFitzroyAustralia
- University of Melbourne, Department of Medicine at St. Vincent’s HospitalFitzroyAustralia
| | | | | | - Tsuyoshi Isojima
- St. Vincent’s Institute of Medical ResearchFitzroyAustralia
- Department of Pediatrics, Teikyo University School of MedicineTokyoJapan
| | - Jonathan H Gooi
- St. Vincent’s Institute of Medical ResearchFitzroyAustralia
- Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Biotechnology Institute, University of MelbourneParkvilleAustralia
| | - T John Martin
- St. Vincent’s Institute of Medical ResearchFitzroyAustralia
- University of Melbourne, Department of Medicine at St. Vincent’s HospitalFitzroyAustralia
| | - Natalie A Sims
- St. Vincent’s Institute of Medical ResearchFitzroyAustralia
- University of Melbourne, Department of Medicine at St. Vincent’s HospitalFitzroyAustralia
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10
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Xie J, Guo J, Kanwal Z, Wu M, Lv X, Ibrahim NA, Li P, Buabeid MA, Arafa ESA, Sun Q. Calcitonin and Bone Physiology: In Vitro, In Vivo, and Clinical Investigations. Int J Endocrinol 2020; 2020:3236828. [PMID: 32963524 PMCID: PMC7501564 DOI: 10.1155/2020/3236828] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 08/18/2020] [Accepted: 08/27/2020] [Indexed: 12/15/2022] Open
Abstract
Calcitonin was discovered as a peptide hormone that was known to reduce the calcium levels in the systemic circulation. This hypocalcemic effect is produced due to multiple reasons such as inhibition of bone resorption or suppression of calcium release from the bone. Thus, calcitonin was said as a primary regulator of the bone resorption process. This is the reason why calcitonin has been used widely in clinics for the treatment of bone disorders such as osteoporosis, hypercalcemia, and Paget's disease. However, presently calcitonin usage is declined due to the development of efficacious formulations of new drugs. Calcitonin gene-related peptides and several other peptides such as intermedin, amylin, and adrenomedullin (ADM) are categorized in calcitonin family. These peptides are known for the structural similarity with calcitonin. Aside from having a similar structure, these peptides have few overlapping biological activities and signal transduction action through related receptors. However, several other activities are also present that are peptide specific. In vitro and in vivo studies documented the posttreatment effects of calcitonin peptides, i.e., positive effect on bone osteoblasts and their formation and negative effect on osteoclasts and their resorption. The recent research studies carried out on genetically modified mice showed the inhibition of osteoclast activity by amylin, while astonishingly calcitonin plays its role by suppressing osteoblast and bone turnover. This article describes the review of the bone, the activity of the calcitonin family of peptides, and the link between them.
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Affiliation(s)
- Jingbo Xie
- Department of Orthopedics, Fengcheng People's Hospital, Fengcheng, Jiangxi 331100, China
| | - Jian Guo
- Department of the Second Orthopedics, Hongdu Hospital of Traditional Chinese Medicine Affiliated to Jiangxi University of Traditional Chinese Medicine, Nanchang Hongdu Traditional Chinese Medicine Hospital, Nanchang, Jiangxi 330008, China
| | | | - Mingzheng Wu
- Department of Orthopaedics, Pu'ai Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430000, China
| | - Xiangyang Lv
- Department of Orthopaedics, Xi'an International Medical Center Hospital, Xi'an, Shaanxi 710100, China
| | | | - Ping Li
- Department of Orthopaedics, Ya'an People's Hospital, Ya'an, Sichuan 625000, China
| | | | | | - Qingshan Sun
- Department of Orthopedics, The Third Hospital of Shandong Province, Jinan, Shandong 250031, China
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11
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Alternating Differentiation and Dedifferentiation between Mature Osteoblasts and Osteocytes. Sci Rep 2019; 9:13842. [PMID: 31554848 PMCID: PMC6761144 DOI: 10.1038/s41598-019-50236-7] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Accepted: 09/09/2019] [Indexed: 12/22/2022] Open
Abstract
Osteocytes are terminally differentiated osteoblasts embedded in the bone matrix. Evidence indicates that cells in the mesenchymal lineage possess plasticity. However, whether or not osteocytes have the capacity to dedifferentiate back into osteoblasts is unclear. This study aimed to clarify the dedifferentiation potential of osteocytes. Mouse calvarial osteoblasts were isolated and maintained in normal two-dimensional (2D) or collagen gel three-dimensional (3D) cultures. In 2D cultures, osteoblasts exhibited a typical fibroblast-like shape with high Alpl and minimal Sost, Fgf23, and Dmp1 expression and osteoblasts formed mineralised nodules. When these osteoblasts were transferred into 3D cultures, they showed a stellate shape with diminished cytoplasm and numerous long processes and expression of Alpl decreased while Sost, Fgf23, and Dmp1 were significantly increased. These cells were in cell cycle arrest and showed suppressed mineralisation, indicating that they were osteocytes. When these osteocytes were recovered from 3D cultures and cultured two-dimensionally again, they regained adequate cytoplasm and lost the long processes, resulting in a fibroblast-like shape. These cells showed high Alpl and low Sost, Fgf23, and Dmp1 expression with a high mineralisation capability, indicating that they were osteoblasts. This report shows that osteocytes possess the capacity to dedifferentiate back into mature osteoblasts without gene manipulation.
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12
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Ho PWM, Chan AS, Pavlos NJ, Sims NA, Martin TJ. Brief exposure to full length parathyroid hormone-related protein (PTHrP) causes persistent generation of cyclic AMP through an endocytosis-dependent mechanism. Biochem Pharmacol 2019; 169:113627. [PMID: 31476292 DOI: 10.1016/j.bcp.2019.113627] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2019] [Accepted: 08/28/2019] [Indexed: 12/17/2022]
Abstract
Parathyroid hormone (PTH)-related protein (PTHrP) (gene name Pthlh) was discovered as the factor responsible for the humoral hypercalcemia of malignancy. It shares such sequence similarity with PTH in the amino-terminal region that the two are equally able to act through a single G protein-coupled receptor, PTH1R. A number of biological activities are ascribed to domains of PTHrP beyond the amino-terminal domain. PTH functions as a circulating hormone, but PTHrP is generated locally in many tissues including bone, where it acts as a paracrine factor on osteoblasts and osteocytes. The present study compares how PTH and PTHrP influence cyclic AMP (cAMP) formation through adenylyl cyclase, the first event in cell activation through PTH1R. Brief exposure to full length PTHrP(1-141) in several osteoblastic cell culture systems was followed by sustained adenylyl cyclase activity for more than an hour after ligand washout. This effect was dose-dependent and was not found with shorter PTHrP or PTH peptides even though they were fully able to activate adenylyl cyclase with acute treatment. The persistent activation response to PTHrP(1-141) was seen also with later events in the cAMP/PKA pathway, including persistent activation of CRE-luciferase and sustained regulation of several CREB-responsive mRNAs, up to 24 h after the initial exposure. Pharmacologic blockade of endocytosis prevented the persistent activation of cAMP and gene responses. We conclude that full length PTHrP, the likely local physiological effector in bone, differs in intracellular action to PTH by undergoing endosomal translocation to induce a prolonged adenylyl cyclase activation in its target cells.
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Affiliation(s)
- Patricia W M Ho
- Bone Biology and Disease Unit, St. Vincent's Institute of Medical Research, Melbourne, Victoria 3065, Australia
| | - Audrey S Chan
- Bone Biology and Disease Unit, St. Vincent's Institute of Medical Research, Melbourne, Victoria 3065, Australia; School of Biomedical Sciences, The University of Western Australia, Nedlands, Western Australia 6009, Australia
| | - Nathan J Pavlos
- School of Biomedical Sciences, The University of Western Australia, Nedlands, Western Australia 6009, Australia
| | - Natalie A Sims
- Bone Biology and Disease Unit, St. Vincent's Institute of Medical Research, Melbourne, Victoria 3065, Australia; Department of Medicine, The University of Melbourne, St. Vincent's Hospital, Melbourne, Victoria 3065, Australia
| | - T John Martin
- Bone Biology and Disease Unit, St. Vincent's Institute of Medical Research, Melbourne, Victoria 3065, Australia; Department of Medicine, The University of Melbourne, St. Vincent's Hospital, Melbourne, Victoria 3065, Australia.
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13
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Increased autophagy in EphrinB2-deficient osteocytes is associated with elevated secondary mineralization and brittle bone. Nat Commun 2019; 10:3436. [PMID: 31366886 PMCID: PMC6668467 DOI: 10.1038/s41467-019-11373-9] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2018] [Accepted: 07/10/2019] [Indexed: 12/30/2022] Open
Abstract
Mineralized bone forms when collagen-containing osteoid accrues mineral crystals. This is initiated rapidly (primary mineralization), and continues slowly (secondary mineralization) until bone is remodeled. The interconnected osteocyte network within the bone matrix differentiates from bone-forming osteoblasts; although osteoblast differentiation requires EphrinB2, osteocytes retain its expression. Here we report brittle bones in mice with osteocyte-targeted EphrinB2 deletion. This is not caused by low bone mass, but by defective bone material. While osteoid mineralization is initiated at normal rate, mineral accrual is accelerated, indicating that EphrinB2 in osteocytes limits mineral accumulation. No known regulators of mineralization are modified in the brittle cortical bone but a cluster of autophagy-associated genes are dysregulated. EphrinB2-deficient osteocytes displayed more autophagosomes in vivo and in vitro, and EphrinB2-Fc treatment suppresses autophagy in a RhoA-ROCK dependent manner. We conclude that secondary mineralization involves EphrinB2-RhoA-limited autophagy in osteocytes, and disruption leads to a bone fragility independent of bone mass. Osteoblasts mediate bone formation, and their differentiation requires expression of EphrinB2. Here, the authors show that EphrinB2 is also expressed by osteocytes, and that its genetic ablation in mice is associated with altered autophagy, elevated mineralization and brittle bone.
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14
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McGregor NE, Murat M, Elango J, Poulton IJ, Walker EC, Crimeen-Irwin B, Ho PWM, Gooi JH, Martin TJ, Sims NA. IL-6 exhibits both cis- and trans-signaling in osteocytes and osteoblasts, but only trans-signaling promotes bone formation and osteoclastogenesis. J Biol Chem 2019; 294:7850-7863. [PMID: 30923130 DOI: 10.1074/jbc.ra119.008074] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Revised: 03/25/2019] [Indexed: 11/06/2022] Open
Abstract
Interleukin 6 (IL-6) supports development of bone-resorbing osteoclasts by acting early in the osteoblast lineage via membrane-bound (cis) or soluble (trans) receptors. Here, we investigated how IL-6 signals and modifies gene expression in differentiated osteoblasts and osteocytes and determined whether these activities can promote bone formation or support osteoclastogenesis. Moreover, we used a genetically altered mouse with circulating levels of the pharmacological IL-6 trans-signaling inhibitor sgp130-Fc to determine whether IL-6 trans-signaling is required for normal bone growth and remodeling. We found that IL-6 increases suppressor of cytokine signaling 3 (Socs3) and CCAAT enhancer-binding protein δ (Cebpd) mRNA levels and promotes signal transducer and activator of transcription 3 (STAT3) phosphorylation by both cis- and trans-signaling in cultured osteocytes. In contrast, RANKL (Tnfsf11) mRNA levels were elevated only by trans-signaling. Furthermore, we observed soluble IL-6 receptor release and ADAM metallopeptidase domain 17 (ADAM17) sheddase expression by osteocytes. Despite the observation that IL-6 cis-signaling occurs, IL-6 stimulated bone formation in vivo only via trans-signaling. Although IL-6 stimulated RANKL (Tnfsf11) mRNA in osteocytes, these cells did not support osteoclast formation in response to IL-6 alone; binucleated TRAP+ cells formed, and only in response to trans-signaling. Finally, pharmacological, sgp130-Fc-mediated inhibition of IL-6 trans-signaling did not impair bone growth or remodeling unless mice had circulating sgp130-Fc levels > 10 μg/ml. At those levels, osteopenia and impaired bone growth occurred, reducing bone strength. We conclude that high sgp130-Fc levels may have detrimental off-target effects on the skeleton.
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Affiliation(s)
- Narelle E McGregor
- From the Bone Cell Biology and Disease Unit, St. Vincent's Institute of Medical Research, Melbourne, Victoria 3065, Australia
| | - Melissa Murat
- From the Bone Cell Biology and Disease Unit, St. Vincent's Institute of Medical Research, Melbourne, Victoria 3065, Australia.,the Department of Physiology, Anatomy, and Microbiology, La Trobe University, Bundoora, Victoria 3086, Australia
| | - Jeevithan Elango
- From the Bone Cell Biology and Disease Unit, St. Vincent's Institute of Medical Research, Melbourne, Victoria 3065, Australia.,the Department of Marine Bio-Pharmacology, College of Food Science and Technology, Shanghai Ocean University, Shanghai 201306, China
| | - Ingrid J Poulton
- From the Bone Cell Biology and Disease Unit, St. Vincent's Institute of Medical Research, Melbourne, Victoria 3065, Australia
| | - Emma C Walker
- From the Bone Cell Biology and Disease Unit, St. Vincent's Institute of Medical Research, Melbourne, Victoria 3065, Australia
| | - Blessing Crimeen-Irwin
- From the Bone Cell Biology and Disease Unit, St. Vincent's Institute of Medical Research, Melbourne, Victoria 3065, Australia
| | - Patricia W M Ho
- From the Bone Cell Biology and Disease Unit, St. Vincent's Institute of Medical Research, Melbourne, Victoria 3065, Australia
| | - Jonathan H Gooi
- the Department of Medicine, University of Melbourne, St. Vincent's Hospital, Melbourne, Victoria 3065, Australia, and.,the Structural Biology Unit, St. Vincent's Institute of Medical Research, Melbourne, Victoria 3065, Australia
| | - T John Martin
- From the Bone Cell Biology and Disease Unit, St. Vincent's Institute of Medical Research, Melbourne, Victoria 3065, Australia.,the Department of Medicine, University of Melbourne, St. Vincent's Hospital, Melbourne, Victoria 3065, Australia, and
| | - Natalie A Sims
- From the Bone Cell Biology and Disease Unit, St. Vincent's Institute of Medical Research, Melbourne, Victoria 3065, Australia, .,the Department of Medicine, University of Melbourne, St. Vincent's Hospital, Melbourne, Victoria 3065, Australia, and
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15
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Naot D, Musson DS, Cornish J. The Activity of Peptides of the Calcitonin Family in Bone. Physiol Rev 2019; 99:781-805. [PMID: 30540227 DOI: 10.1152/physrev.00066.2017] [Citation(s) in RCA: 82] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Calcitonin was discovered over 50 yr ago as a new hormone that rapidly lowers circulating calcium levels. This effect is caused by the inhibition of calcium efflux from bone, as calcitonin is a potent inhibitor of bone resorption. Calcitonin has been in clinical use for conditions of accelerated bone turnover, including Paget's disease and osteoporosis; although in recent years, with the development of drugs that are more potent inhibitors of bone resorption, its use has declined. A number of peptides that are structurally similar to calcitonin form the calcitonin family, which currently includes calcitonin gene-related peptides (αCGRP and βCGRP), amylin, adrenomedullin, and intermedin. Apart from being structurally similar, the peptides signal through related receptors and have some overlapping biological activities, although other activities are peptide specific. In bone, in vitro studies and administration of the peptides to animals generally found inhibitory effects on osteoclasts and bone resorption and positive effects on osteoblasts and bone formation. Surprisingly, studies in genetically modified mice have demonstrated that the physiological role of calcitonin appears to be the inhibition of osteoblast activity and bone turnover, whereas amylin inhibits osteoclast activity. The review article focuses on the activities of peptides of the calcitonin family in bone and the challenges in understanding the relationship between the pharmacological effects and the physiological roles of these peptides.
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Affiliation(s)
- Dorit Naot
- Department of Medicine, University of Auckland , Auckland , New Zealand
| | - David S Musson
- Department of Medicine, University of Auckland , Auckland , New Zealand
| | - Jillian Cornish
- Department of Medicine, University of Auckland , Auckland , New Zealand
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16
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Abstract
Bone tissue is comprised of a collagen-rich matrix containing non-collagenous organic compounds, strengthened by mineral crystals. Bone strength reflects the amount and structure of bone, as well as its quality. These qualities are determined and maintained by osteoblasts (bone-forming cells) and osteoclasts (bone-resorbing cells) on the surface of the bone and osteocytes embedded within the bone matrix. Bone development and growth also involves cartilage cells (chondrocytes). These cells do not act in isolation, but function in a coordinated manner, including co-ordination within each lineage, between the cells of bone, and between these cells and other cell types within the bone microenvironment. This chapter will briefly outline the cells of bone, their major functions, and some communication pathways responsible for controlling bone development and remodeling.
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Affiliation(s)
- Niloufar Ansari
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, VIC, Australia
| | - Natalie A Sims
- Bone Biology and Disease Unit, St. Vincent's Institute of Medical Research, Melbourne, VIC, Australia.
- Department of Medicine, The University of Melbourne, St. Vincent's Hospital, Melbourne, VIC, Australia.
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17
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Gooi JH, Chia LY, Vrahnas C, Sims NA. Isolation, Purification, Generation, and Culture of Osteocytes. Methods Mol Biol 2019; 1914:39-51. [PMID: 30729459 DOI: 10.1007/978-1-4939-8997-3_3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Osteocytes reside within bone matrix and produce both paracrine and endocrine factors that influence the skeleton and other tissues. Despite their abundance and physiological importance, osteocytes have been difficult to study in vitro because they are difficult to extract and purify, and do not retain their phenotype in standard culture conditions. However, new techniques for this purpose are emerging. This chapter will describe three methods we use to study osteocytes: (1) isolating and purifying primary osteocytes from murine bone, with and without hematopoietic-lineage depletion, (2) differentiating cultured osteoblasts (or osteoblast cell lines) until they reach a stage of osteocytic gene expression, and (3) using the Ocy454 osteocyte-like cell line.
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Affiliation(s)
- Jonathan H Gooi
- Department of Medicine, St. Vincent's Hospital Melbourne, The University of Melbourne, Melbourne, VIC, Australia
| | - Ling Yeong Chia
- Department of Medicine, St. Vincent's Hospital Melbourne, The University of Melbourne, Melbourne, VIC, Australia
- St. Vincent's Institute of Medical Research, Melbourne, VIC, Australia
- Drug Discovery Biology, Monash Institute of Pharmaceutical Sciences, Monash University, Clayton, VIC, Australia
| | - Christina Vrahnas
- Department of Medicine, St. Vincent's Hospital Melbourne, The University of Melbourne, Melbourne, VIC, Australia
- St. Vincent's Institute of Medical Research, Melbourne, VIC, Australia
- MRC Protein Phosphorylation & Ubiquitylation Unit, University of Dundee, Sir James Black Centre, Dundee, UK
| | - Natalie A Sims
- Department of Medicine, St. Vincent's Hospital Melbourne, The University of Melbourne, Melbourne, VIC, Australia.
- St. Vincent's Institute of Medical Research, Melbourne, VIC, Australia.
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18
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Vrahnas C, Buenzli PR, Pearson TA, Pennypacker BL, Tobin MJ, Bambery KR, Duong LT, Sims NA. Differing Effects of Parathyroid Hormone, Alendronate, and Odanacatib on Bone Formation and on the Mineralization Process in Intracortical and Endocortical Bone of Ovariectomized Rabbits. Calcif Tissue Int 2018; 103:625-637. [PMID: 30019315 DOI: 10.1007/s00223-018-0455-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Accepted: 07/10/2018] [Indexed: 02/02/2023]
Abstract
Bone is formed by deposition of a collagen-containing matrix (osteoid) that hardens over time as mineral crystals accrue and are modified; this continues until bone remodeling renews that site. Pharmacological agents for osteoporosis differ in their effects on bone remodeling, and we hypothesized that they may differently modify bone mineral accrual. We, therefore, assessed newly formed bone in mature ovariectomized rabbits treated with the anti-resorptive bisphosphonate alendronate (ALN-100µ g/kg/2×/week), the anabolic parathyroid hormone (PTH (1-34)-15µ g/kg/5×/week), or the experimental anti-resorptive odanacatib (ODN 7.5 µM/day), which suppresses bone resorption without suppressing bone formation. Treatments were administered for 10 months commencing 6 months after ovariectomy (OVX). Strength testing, histomorphometry, and synchrotron Fourier-transform infrared microspectroscopy were used to measure bone strength, bone formation, and mineral accrual, respectively, in newly formed endocortical and intracortical bone. In Sham and OVX endocortical and intracortical bone, three modifications occurred as the bone matrix aged: mineral accrual (increase in mineral:matrix ratio), carbonate substitution (increase in carbonate:mineral ratio), and collagen molecular compaction (decrease in amide I:II ratio). ALN suppressed bone formation but mineral accrued normally at those sites where bone formation occurred. PTH stimulated bone formation on endocortical, periosteal, and intracortical bone surfaces, but mineral accrual and carbonate substitution were suppressed, particularly in intracortical bone. ODN treatment did not suppress bone formation, but newly deposited endocortical bone matured more slowly with ODN, and ODN-treated intracortical bone had less carbonate substitution than controls. In conclusion, these agents differ in their effects on the bone matrix. While ALN suppresses bone formation, it does not modify bone mineral accrual in endocortical or intracortical bone. While ODN does not suppress bone formation, it slows matrix maturation. PTH stimulates modelling-based bone formation not only on endocortical and trabecular surfaces, but may also do so in intracortical bone; at this site, new bone deposited contains less mineral than normal.
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Affiliation(s)
- Christina Vrahnas
- St. Vincent's Institute of Medical Research, Fitzroy, VIC, Australia
- Department of Medicine at St. Vincent's Hospital, The University of Melbourne, Fitzroy, VIC, Australia
| | - Pascal R Buenzli
- School of Mathematical Sciences, Queensland University of Technology, Brisbane, Australia
| | - Thomas A Pearson
- St. Vincent's Institute of Medical Research, Fitzroy, VIC, Australia
| | | | - Mark J Tobin
- The Australian Synchrotron, Clayton, VIC, Australia
| | - Keith R Bambery
- The Australian Synchrotron, Clayton, VIC, Australia
- Australian Nuclear Science and Technology Organisation, The Australian Synchrotron, Lucas Heights, NSW, Australia
| | - Le T Duong
- MRL, Merck & Co., Inc., West Point, PA, USA
| | - Natalie A Sims
- St. Vincent's Institute of Medical Research, Fitzroy, VIC, Australia.
- Department of Medicine at St. Vincent's Hospital, The University of Melbourne, Fitzroy, VIC, Australia.
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19
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Li L, Wang Y, Zhang N, Zhang Y, Lin J, Qiu X, Gui Y, Wang F, Li D, Wang L. Heterozygous deletion of LRP5 gene in mice alters profile of immune cells and modulates differentiation of osteoblasts. Biosci Trends 2018; 12:266-274. [PMID: 29899194 DOI: 10.5582/bst.2018.01013] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Skeletal homeostasis is dynamically influenced by the immune system. Low density lipoprotein receptor-related protein-5 (LRP5) is a co-receptor of the Wnt signaling pathway, which modulates bone metabolism in humans and mice. Immune disorders can lead to abnormal bone metabolism. It is unclear whether and how LRP5 alters the balance of the immune system to modulate bone homeostasis. In this study, we used primary osteoblast to detect the differentiation of osteoblasts in vitro, the immune cells of spleen and bone marrow of 6-month old LRP5 heterozygote (HZ) and wild-type (WT) mice were analyzed by Flow cytometry. We found that LRP5+/- could influence the differentiation of osteoblasts by decreasing the mRNA level of Osterix, and increasing the mRNA level of Runx2 and the ratio of receptor activator for nuclear factor-κB ligand/osteoprotegerin (RANKL/OPG). In the LRP5+/- mice, percentages of NK cells, CD3e+ cells, and CD8a+ T cells were increased in both spleen and bone marrow, and percentages of CD106+ cells and CD11c+ cells were increased in spleen while decreased in bone marrow, conversely, CD62L+ cells were decreased in spleen while increased in bone marrow compared to the WT mice. Percentages of CD4+ cells, CD14+ cells, and CD254+ cells were increased in the spleen, and CTLA4+ cells were increased in the bone marrow of the LRP5+/- mice. The mRNA level of Wnt signaling molecules such as β-catenin, and c-myc were decreased and APC was increased in spleen lymphocytes and bone marrow lymphocytes, and the mRNA level of Wnt3a was decreased in spleen lymphocytes while no change in bone marrow lymphocytes was seen with silencing LRP5 by specific small interfering RNA. In conclusion, heterozygous deletion of the LRP5 gene in mice could alter the profile of the immune cells, influence the balance of immune environment, and modulate bone homeostasis, which might present a potential mechanism to explore the Wnt signaling pathway in the modulation of the immune system.
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Affiliation(s)
- Lisha Li
- Obstetrics and Gynecology Hospital of Fudan University.,The Academy of Integrative Medicine of Fudan University.,Shanghai Key Laboratory of Female Reproductive Endocrine-related Diseases
| | - Yan Wang
- Obstetrics and Gynecology Hospital of Fudan University.,The Academy of Integrative Medicine of Fudan University.,Shanghai Key Laboratory of Female Reproductive Endocrine-related Diseases
| | - Na Zhang
- Obstetrics and Gynecology Hospital of Fudan University.,The Academy of Integrative Medicine of Fudan University.,Shanghai Key Laboratory of Female Reproductive Endocrine-related Diseases
| | - Yang Zhang
- First Affiliated Hospital of Heilongjiang University of Chinese Medicine
| | - Jing Lin
- Obstetrics and Gynecology Hospital of Fudan University.,The Academy of Integrative Medicine of Fudan University.,Shanghai Key Laboratory of Female Reproductive Endocrine-related Diseases
| | - Xuemin Qiu
- Obstetrics and Gynecology Hospital of Fudan University.,The Academy of Integrative Medicine of Fudan University.,Shanghai Key Laboratory of Female Reproductive Endocrine-related Diseases
| | - Yuyan Gui
- Obstetrics and Gynecology Hospital of Fudan University
| | - Feifei Wang
- Obstetrics and Gynecology Hospital of Fudan University.,The Academy of Integrative Medicine of Fudan University.,Shanghai Key Laboratory of Female Reproductive Endocrine-related Diseases
| | - Dajin Li
- Obstetrics and Gynecology Hospital of Fudan University.,The Academy of Integrative Medicine of Fudan University.,Shanghai Key Laboratory of Female Reproductive Endocrine-related Diseases
| | - Ling Wang
- Obstetrics and Gynecology Hospital of Fudan University.,The Academy of Integrative Medicine of Fudan University.,Shanghai Key Laboratory of Female Reproductive Endocrine-related Diseases.,Laboratory for Reproductive Immunology, Hospital & Institute of Obstetrics and Gynecology, IBS, Fudan University Shanghai Medical College
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20
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Ansari N, Ho PW, Crimeen-Irwin B, Poulton IJ, Brunt AR, Forwood MR, Divieti Pajevic P, Gooi JH, Martin TJ, Sims NA. Autocrine and Paracrine Regulation of the Murine Skeleton by Osteocyte-Derived Parathyroid Hormone-Related Protein. J Bone Miner Res 2018; 33:137-153. [PMID: 28914969 DOI: 10.1002/jbmr.3291] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Revised: 08/28/2017] [Accepted: 09/06/2017] [Indexed: 12/14/2022]
Abstract
Parathyroid hormone-related protein (PTHrP) and parathyroid hormone (PTH) have N-terminal domains that bind a common receptor, PTHR1. N-terminal PTH (teriparatide) and now a modified N-terminal PTHrP (abaloparatide) are US Food and Drug Administration (FDA)-approved therapies for osteoporosis. In physiology, PTHrP does not normally circulate at significant levels, but acts locally, and osteocytes, cells residing within the bone matrix, express both PTHrP and the PTHR1. Because PTHR1 in osteocytes is required for normal bone resorption, we determined how osteocyte-derived PTHrP influences the skeleton. We observed that adult mice with low PTHrP in osteocytes (targeted with the Dmp1(10kb)-Cre) have low trabecular bone volume and osteoblast numbers, but osteoclast numbers were unaffected. In addition, bone size was normal, but cortical bone strength was impaired. Osteocyte-derived PTHrP therefore stimulates bone formation and bone matrix strength, but is not required for normal osteoclastogenesis. PTHrP knockdown and overexpression studies in cultured osteocytes indicate that osteocyte-secreted PTHrP regulates their expression of genes involved in matrix mineralization. We determined that osteocytes secrete full-length PTHrP with no evidence for secretion of lower molecular weight forms containing the N-terminus. We conclude that osteocyte-derived full-length PTHrP acts through both PTHR1 receptor-mediated and receptor-independent actions in a paracrine/autocrine manner to stimulate bone formation and to modify adult cortical bone strength. © 2017 American Society for Bone and Mineral Research.
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Affiliation(s)
- Niloufar Ansari
- St. Vincent's Institute of Medical Research, Fitzroy, Victoria, Australia.,The University of Melbourne, Department of Medicine at St. Vincent's Hospital, Fitzroy, Victoria, Australia
| | - Patricia Wm Ho
- St. Vincent's Institute of Medical Research, Fitzroy, Victoria, Australia
| | | | - Ingrid J Poulton
- St. Vincent's Institute of Medical Research, Fitzroy, Victoria, Australia
| | - Athena R Brunt
- School of Medical Science and Menzies Health Institute Queensland, Griffith University, Gold Coast, Queensland, Australia
| | - Mark R Forwood
- School of Medical Science and Menzies Health Institute Queensland, Griffith University, Gold Coast, Queensland, Australia
| | - Paola Divieti Pajevic
- Department of Molecular and Cell Biology, Boston University Goldman School of Dental Medicine, Boston, MA, USA
| | - Jonathan H Gooi
- The University of Melbourne, Department of Medicine at St. Vincent's Hospital, Fitzroy, Victoria, Australia
| | - T John Martin
- St. Vincent's Institute of Medical Research, Fitzroy, Victoria, Australia.,The University of Melbourne, Department of Medicine at St. Vincent's Hospital, Fitzroy, Victoria, Australia
| | - Natalie A Sims
- St. Vincent's Institute of Medical Research, Fitzroy, Victoria, Australia.,The University of Melbourne, Department of Medicine at St. Vincent's Hospital, Fitzroy, Victoria, Australia
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21
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Scheuren A, Wehrle E, Flohr F, Müller R. Bone mechanobiology in mice: toward single-cell in vivo mechanomics. Biomech Model Mechanobiol 2017; 16:2017-2034. [PMID: 28735414 DOI: 10.1007/s10237-017-0935-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2017] [Accepted: 07/11/2017] [Indexed: 01/27/2023]
Abstract
Mechanically driven bone (re)modeling is a multiscale process mediated through complex interactions between multiple cell types and their microenvironments. However, the underlying mechanisms of how cells respond to mechanical signals are still unclear and are at the focus of the field of bone mechanobiology. Traditionally, this complex process has been addressed by reducing the system to single scales and cell types. It is only recently that more integrative approaches have been established to study bone mechanobiology across multiple scales in which mechanical load at the organ level is related to molecular responses at the cellular level. The availability of mouse loading models and imaging techniques with improved spatial and temporal resolution has made it possible to track dynamic bone (re)modeling at the tissue and cellular level in vivo. Coupled with advanced computational models, the (re)modeling activities at the tissue scale can be associated with the mechanical microenvironment. However, methods are lacking to link the molecular responses of different cell types to their local mechanical microenvironment and bone (re)modeling activities occurring at the tissue scale. With recent improvements in "omics" technologies and single-cell molecular biology, it is now possible to sequence the complete genome and transcriptome of single cells. These technologies offer unique opportunities to comprehensively investigate the cellular transcriptional profiles within their specific microenvironment. By combining single-cell "omics" technologies with well-established tissue-scale models of bone mechanobiology, we propose a mechanomics approach to locally analyze the transcriptome of single cells with respect to their local 3D mechanical in vivo environment.
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Affiliation(s)
- Ariane Scheuren
- Institute for Biomechanics, ETH Zurich, Leopold-Ruzicka-Weg 4, 8093, Zurich, Switzerland
| | - Esther Wehrle
- Institute for Biomechanics, ETH Zurich, Leopold-Ruzicka-Weg 4, 8093, Zurich, Switzerland
| | - Felicitas Flohr
- Institute for Biomechanics, ETH Zurich, Leopold-Ruzicka-Weg 4, 8093, Zurich, Switzerland
| | - Ralph Müller
- Institute for Biomechanics, ETH Zurich, Leopold-Ruzicka-Weg 4, 8093, Zurich, Switzerland.
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22
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Roeder E, Matthews BG, Kalajzic I. Visual reporters for study of the osteoblast lineage. Bone 2016; 92:189-195. [PMID: 27616604 PMCID: PMC5056847 DOI: 10.1016/j.bone.2016.09.004] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/11/2016] [Revised: 09/06/2016] [Accepted: 09/07/2016] [Indexed: 12/24/2022]
Abstract
Advancing our understanding of osteoblast biology and differentiation is critical to elucidate the pathological mechanisms responsible for skeletal diseases such as osteoporosis. Histology and histomorphometry, the classical methods to study osteoblast biology, identify osteoblasts based on their location and morphology and ability to mineralize matrix, but do not clearly define their stage of differentiation. Introduction of visual transgenes into the cells of osteoblast lineage has revolutionized the field and resulted in a paradigm shift that allowed for specific identification and isolation of subpopulations within the osteoblast lineage. Knowledge acquired from the studies based on GFP transgenes has allowed for more precise interpretation of studies analyzing targeted overexpression or deletion of genes in the osteoblast lineage. Here, we provide a condensed overview of the currently available promoter-fluorescent reporter transgenic mice that have been generated and evaluated to varying extents. We cover different stages of the lineage as transgenes have been utilized to identify osteoprogenitors, pre-osteoblasts, osteoblasts, or osteocytes. We show that each of these promoters present with advantages and disadvantages. The studies based on the use of these reporter mice have improved our understanding of bone biology. They constitute attractive models to target osteoblasts and help to understand their cell biology.
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Affiliation(s)
- Emilie Roeder
- Department of Reconstructive Sciences, University of Connecticut Health Center, Farmington, CT 06030, USA
| | - Brya G Matthews
- Department of Reconstructive Sciences, University of Connecticut Health Center, Farmington, CT 06030, USA
| | - Ivo Kalajzic
- Department of Reconstructive Sciences, University of Connecticut Health Center, Farmington, CT 06030, USA; Department of Pathophysiology, University of Osijek, Osijek, Croatia.
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Sims NA. Senescent Osteocytes: Do They Cause Damage and Can They Be Targeted to Preserve the Skeleton? J Bone Miner Res 2016; 31:1917-1919. [PMID: 27653182 DOI: 10.1002/jbmr.2994] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Revised: 09/09/2016] [Accepted: 09/13/2016] [Indexed: 02/01/2023]
Affiliation(s)
- Natalie A Sims
- St. Vincent's Institute of Medical Research, Fitzroy, Australia.,Department of Medicine at St. Vincent's Hospital, The University of Melbourne, Fitzroy, Australia
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24
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Osteocyte isolation and culture methods. BONEKEY REPORTS 2016; 5:838. [PMID: 27648260 DOI: 10.1038/bonekey.2016.65] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Accepted: 07/29/2016] [Indexed: 11/08/2022]
Abstract
The aim of this paper is to present several popular methods for in vitro culture of osteocytes and osteocyte cell lines. Osteocytes are located extremely suitably within the calcified bone matrix to sense mechanical signals, and are equipped with a multitude of molecular features that allow mechanosensing. However, osteocytes are more than specialized mechanosensing cells. Several signaling molecules are preferentially produced by osteocytes, and osteocytes hold a tight reign over osteoblast and osteoclast formation and activity, but also have a role as endocrine cell, communicating with muscles or organs as remote as the kidneys. In order to facilitate further research into this fascinating cell type, three protocols will be provided in this paper. The first protocol will be on the culture of mouse (early) osteocyte cell lines, the second on the isolation and culture of primary mouse bone cells, and the third on the culture of fully embedded human osteocytes within their own three-dimensional bone matrix.
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Prideaux M, Schutz C, Wijenayaka AR, Findlay DM, Campbell DG, Solomon LB, Atkins GJ. Isolation of osteocytes from human trabecular bone. Bone 2016; 88:64-72. [PMID: 27109824 DOI: 10.1016/j.bone.2016.04.017] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Revised: 03/29/2016] [Accepted: 04/17/2016] [Indexed: 12/22/2022]
Abstract
Osteocytes are essential regulators of bone homeostasis. However, they are difficult to study due to their location within the bone mineralised matrix. Although several techniques have been published for the isolation of osteocytes from mouse bone, no such technique has been described for human osteocytes. We have therefore developed a protocol for the isolation of osteocytes from human trabecular bone samples acquired during surgery. The cells were digested from the bone matrix by sequential collagenase and ethylenediaminetetraacetic acid (EDTA) digestions and the cells from later digests displayed characteristic dendritic osteocyte morphology when cultured ex vivo. Furthermore, the cells expressed characteristic osteocyte marker genes, such as E11, dentin matrix protein 1 (DMP1), SOST, matrix extracellular phosphoglycoprotein (MEPE) and phosphate regulating endopeptidase homologue, X-linked (PHEX). In addition, genes associated with osteocyte perilacunar remodelling, including matrix metallopeptidase-13 (MMP13), cathepsin K (CTSK) and carbonic anhydrase 2 (CAR2) were expressed. The cells also responded to parathyroid hormone (PTH) by downregulating SOST mRNA expression and to 1α,25-dihydroxyvitamin D3 (1,25D) by upregulating fibroblast growth factor 23 (FGF23) mRNA expression. Therefore, the cells behave in a similar manner to osteocytes in vivo. These cells represent an important tool in enhancing current knowledge in human osteocyte biology.
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Affiliation(s)
- Matthew Prideaux
- Centre for Orthopaedic and Trauma Research, Discipline of Orthopaedics and Trauma, University of Adelaide, Adelaide, SA 5005, Australia.
| | - Christine Schutz
- Centre for Orthopaedic and Trauma Research, Discipline of Orthopaedics and Trauma, University of Adelaide, Adelaide, SA 5005, Australia; Wakefield Orthopaedic Clinic, Adelaide, SA 5000, Australia
| | - Asiri R Wijenayaka
- Centre for Orthopaedic and Trauma Research, Discipline of Orthopaedics and Trauma, University of Adelaide, Adelaide, SA 5005, Australia
| | - David M Findlay
- Centre for Orthopaedic and Trauma Research, Discipline of Orthopaedics and Trauma, University of Adelaide, Adelaide, SA 5005, Australia
| | | | - Lucian B Solomon
- Centre for Orthopaedic and Trauma Research, Discipline of Orthopaedics and Trauma, University of Adelaide, Adelaide, SA 5005, Australia
| | - Gerald J Atkins
- Centre for Orthopaedic and Trauma Research, Discipline of Orthopaedics and Trauma, University of Adelaide, Adelaide, SA 5005, Australia.
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26
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Duong LT, Leung AT, Langdahl B. Cathepsin K Inhibition: A New Mechanism for the Treatment of Osteoporosis. Calcif Tissue Int 2016; 98:381-97. [PMID: 26335104 DOI: 10.1007/s00223-015-0051-0] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Accepted: 08/10/2015] [Indexed: 12/22/2022]
Abstract
Cathepsin K (CatK), a cysteine protease, is highly expressed by osteoclasts and very efficiently degrades type I collagen, the major component of the organic bone matrix. Robust genetic and pharmacological preclinical studies consistently demonstrate that CatK inhibition increases bone mass, improves bone microarchitecture and strength. Recent advances in the understanding of the molecular and cellular mechanisms involved in bone modeling and remodeling suggest that inhibition of CatK decreases bone resorption, but increases the number of cells of osteoclast lineage. This in turn maintains the signals for bone formation, and perhaps may even increase bone formation on some cortical surfaces. Several CatK inhibitors, including relacatib, balicatib, odanacatib and ONO-5334 had entered clinical development for metabolic bone disorders with increased bone resorption, such as postmenopausal osteoporosis. However, odanacatib (ODN) is the only candidate continuing in development. ODN is a highly selective oral CatK inhibitor dosed once-weekly in humans. In a Phase 2 clinical trial, postmenopausal women treated with ODN had sustained reductions of bone resorption markers, while bone formation markers returned to normal after an initial decline within the first 2 years on treatment. In turn areal bone mineral density increased continuously at both spine and hip for up to 5 years. ODN has also been demonstrated to improve bone mass in women with postmenopausal osteoporosis previously treated with alendronate and in men with osteoporosis. ODN is currently in a worldwide Phase 3 fracture outcome trial for the treatment of postmenopausal osteoporosis with interim results supporting its anti-fracture efficacy at the spine, hip and non-vertebral sites.
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Affiliation(s)
| | | | - Bente Langdahl
- Department of Endocrinology and Internal Medicine, Aarhus University Hospital, Aarhus, Denmark
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Osteoclast-derived exosomal miR-214-3p inhibits osteoblastic bone formation. Nat Commun 2016; 7:10872. [PMID: 26947250 PMCID: PMC4786676 DOI: 10.1038/ncomms10872] [Citation(s) in RCA: 383] [Impact Index Per Article: 47.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2015] [Accepted: 01/28/2016] [Indexed: 12/15/2022] Open
Abstract
Emerging evidence indicates that osteoclasts direct osteoblastic bone formation. MicroRNAs (miRNAs) have a crucial role in regulating osteoclast and osteoblast function. However, whether miRNAs mediate osteoclast-directed osteoblastic bone formation is mostly unknown. Here, we show that increased osteoclastic miR-214-3p associates with both elevated serum exosomal miR-214-3p and reduced bone formation in elderly women with fractures and in ovariectomized (OVX) mice. Osteoclast-specific miR-214-3p knock-in mice have elevated serum exosomal miR-214-3p and reduced bone formation that is rescued by osteoclast-targeted antagomir-214-3p treatment. We further demonstrate that osteoclast-derived exosomal miR-214-3p is transferred to osteoblasts to inhibit osteoblast activity in vitro and reduce bone formation in vivo. Moreover, osteoclast-targeted miR-214-3p inhibition promotes bone formation in ageing OVX mice. Collectively, our results suggest that osteoclast-derived exosomal miR-214-3p transfers to osteoblasts to inhibit bone formation. Inhibition of miR-214-3p in osteoclasts may be a strategy for treating skeletal disorders involving a reduction in bone formation. In previous studies the authors discovered that miR-214 inhibits osteoblastic bone formation. Here they extend on these findings, using ovariectomized mice and samples from patients with bone fractures, to show that miR-214 is a mediator of osteoclast-osteoblast crosstalk.
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28
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Zhang H, Siegel CT, Shuai L, Lai J, Zeng L, Zhang Y, Lai X, Bie P, Bai L. Repair of liver mediated by adult mouse liver neuro-glia antigen 2-positive progenitor cell transplantation in a mouse model of cirrhosis. Sci Rep 2016; 6:21783. [PMID: 26905303 PMCID: PMC4764864 DOI: 10.1038/srep21783] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2015] [Accepted: 02/01/2016] [Indexed: 02/07/2023] Open
Abstract
NG2-expressing cells are a population of periportal vascular stem/progenitors (MLpvNG2(+) cells) that were isolated from healthy adult mouse liver by using a "Percoll-Plate-Wait" procedure. We demonstrated that isolated cells are able to restore liver function after transplantation into a cirrhotic liver, and co-localized with the pericyte marker (immunohistochemistry: PDGFR-β) and CK19. Cells were positive for: stem cell (Sca-1, CD133, Dlk) and liver stem cell markers (EpCAM, CD14, CD24, CD49f); and negative for: hematopoietic (CD34, CD45) and endothelial markers (CD31, vWf, von Willebrand factor). Cells were transplanted (1 × 10(6) cells) in mice with diethylnitrosamine-induced cirrhosis at week 6. Cells showed increased hepatic associated gene expression of alpha-fetoprotein (AFP), Albumin (Alb), Glucose-6-phosphatase (G6Pc), SRY (sex determining region Y)-box 9 (Sox9), hepatic nuclear factors (HNF1a, HNF1β, HNF3β, HNF4α, HNF6, Epithelial cell adhesion molecule (EpCAM), Leucine-rich repeated-containing G-protein coupled receptor 5-positive (Lgr5) and Tyrosine aminotransferase (TAT). Cells showed decreased fibrogenesis, hepatic stellate cell infiltration, Kupffer cells and inflammatory cytokines. Liver function markers improved. In a cirrhotic liver environment, cells could differentiate into hepatic lineages. In addition, grafted MLpvNG2(+) cells could mobilize endogenous stem/progenitors to participate in liver repair. These results suggest that MLpvNG2(+) cells may be novel adult liver progenitors that participate in liver regeneration.
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Affiliation(s)
- Hongyu Zhang
- Hepatobiliary Institute, Southwestern Hospital, No. 30 Gaotanyan, ShapingBa Distract, Chongqing 400038, China
| | - Christopher T. Siegel
- Department of Surgery, Division of Hepatobiliary and Abdominal Organ Transplantation, Case Western Reserve University Hospital, Cleveland OH 44106, USA
| | - Ling Shuai
- Hepatobiliary Institute, Southwestern Hospital, No. 30 Gaotanyan, ShapingBa Distract, Chongqing 400038, China
| | - Jiejuan Lai
- Hepatobiliary Institute, Southwestern Hospital, No. 30 Gaotanyan, ShapingBa Distract, Chongqing 400038, China
| | - Linli Zeng
- Hepatobiliary Institute, Southwestern Hospital, No. 30 Gaotanyan, ShapingBa Distract, Chongqing 400038, China
| | - Yujun Zhang
- Hepatobiliary Institute, Southwestern Hospital, No. 30 Gaotanyan, ShapingBa Distract, Chongqing 400038, China
| | - Xiangdong Lai
- Hepatobiliary Institute, Southwestern Hospital, No. 30 Gaotanyan, ShapingBa Distract, Chongqing 400038, China
| | - Ping Bie
- Hepatobiliary Institute, Southwestern Hospital, No. 30 Gaotanyan, ShapingBa Distract, Chongqing 400038, China
| | - Lianhua Bai
- Hepatobiliary Institute, Southwestern Hospital, No. 30 Gaotanyan, ShapingBa Distract, Chongqing 400038, China
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Tonna S, Poulton IJ, Taykar F, Ho PWM, Tonkin B, Crimeen-Irwin B, Tatarczuch L, McGregor NE, Mackie EJ, Martin TJ, Sims NA. Chondrocytic ephrin B2 promotes cartilage destruction by osteoclasts in endochondral ossification. Development 2016; 143:648-57. [PMID: 26755702 DOI: 10.1242/dev.125625] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2015] [Accepted: 12/24/2015] [Indexed: 12/17/2022]
Abstract
The majority of the skeleton arises by endochondral ossification, whereby cartilaginous templates expand and are resorbed by osteoclasts then replaced by osteoblastic bone formation. Ephrin B2 is a receptor tyrosine kinase expressed by osteoblasts and growth plate chondrocytes that promotes osteoblast differentiation and inhibits osteoclast formation. We investigated the role of ephrin B2 in endochondral ossification using Osx1Cre-targeted gene deletion. Neonatal Osx1Cre.Efnb2(Δ/Δ) mice exhibited a transient osteopetrosis demonstrated by increased trabecular bone volume with a high content of growth plate cartilage remnants and increased cortical thickness, but normal osteoclast numbers within the primary spongiosa. Osteoclasts at the growth plate had an abnormal morphology and expressed low levels of tartrate-resistant acid phosphatase; this was not observed in more mature bone. Electron microscopy revealed a lack of sealing zones and poor attachment of Osx1Cre.Efnb2(Δ/Δ) osteoclasts to growth plate cartilage. Osteoblasts at the growth plate were also poorly attached and impaired in their ability to deposit osteoid. By 6 months of age, trabecular bone mass, osteoclast morphology and osteoid deposition by Osx1Cre.Efnb2(Δ/Δ) osteoblasts were normal. Cultured chondrocytes from Osx1Cre.Efnb2(Δ/Δ) neonates showed impaired support of osteoclastogenesis but no significant change in Rankl (Tnfsf11) levels, whereas Adamts4 levels were significantly reduced. A population of ADAMTS4(+) early hypertrophic chondrocytes seen in controls was absent from Osx1Cre.Efnb2(Δ/Δ) neonates. This suggests that Osx1Cre-expressing cells, including hypertrophic chondrocytes, are dependent on ephrin B2 for their production of cartilage-degrading enzymes, including ADAMTS4, and this might be required for attachment of osteoclasts and osteoblasts to the cartilage surface during endochondral ossification.
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Affiliation(s)
- Stephen Tonna
- St Vincent's Institute of Medical Research, Fitzroy, Victoria 3065, Australia The University of Melbourne, Department of Medicine at St Vincent's Hospital, Fitzroy, Victoria 3065, Australia
| | - Ingrid J Poulton
- St Vincent's Institute of Medical Research, Fitzroy, Victoria 3065, Australia
| | - Farzin Taykar
- St Vincent's Institute of Medical Research, Fitzroy, Victoria 3065, Australia
| | - Patricia W M Ho
- St Vincent's Institute of Medical Research, Fitzroy, Victoria 3065, Australia
| | - Brett Tonkin
- St Vincent's Institute of Medical Research, Fitzroy, Victoria 3065, Australia
| | | | - Liliana Tatarczuch
- The University of Melbourne, Faculty of Veterinary and Agricultural Sciences, Parkville 3010, Australia
| | - Narelle E McGregor
- St Vincent's Institute of Medical Research, Fitzroy, Victoria 3065, Australia
| | - Eleanor J Mackie
- The University of Melbourne, Faculty of Veterinary and Agricultural Sciences, Parkville 3010, Australia
| | - T John Martin
- St Vincent's Institute of Medical Research, Fitzroy, Victoria 3065, Australia The University of Melbourne, Department of Medicine at St Vincent's Hospital, Fitzroy, Victoria 3065, Australia
| | - Natalie A Sims
- St Vincent's Institute of Medical Research, Fitzroy, Victoria 3065, Australia The University of Melbourne, Department of Medicine at St Vincent's Hospital, Fitzroy, Victoria 3065, Australia
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30
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Yamamoto Y, Itoh S, Yamauchi Y, Matsushita K, Ikeda S, Naruse H, Hayashi M. Density Gradient Centrifugation for the Isolation of Cells of Multiple Lineages. J Cell Biochem 2015; 116:2709-14. [DOI: 10.1002/jcb.25270] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2015] [Accepted: 06/19/2015] [Indexed: 11/07/2022]
Affiliation(s)
- Yumiko Yamamoto
- Department of Restorative Dentistry and Endodontology; Osaka University Graduate School of Dentistry; Osaka Japan
| | - Shousaku Itoh
- Department of Restorative Dentistry and Endodontology; Osaka University Graduate School of Dentistry; Osaka Japan
| | - Yukako Yamauchi
- Department of Restorative Dentistry and Endodontology; Osaka University Graduate School of Dentistry; Osaka Japan
| | - Kenta Matsushita
- Department of Restorative Dentistry and Endodontology; Osaka University Graduate School of Dentistry; Osaka Japan
| | - Shun Ikeda
- Department of Restorative Dentistry and Endodontology; Osaka University Graduate School of Dentistry; Osaka Japan
| | - Haruna Naruse
- Department of Restorative Dentistry and Endodontology; Osaka University Graduate School of Dentistry; Osaka Japan
| | - Mikako Hayashi
- Department of Restorative Dentistry and Endodontology; Osaka University Graduate School of Dentistry; Osaka Japan
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31
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Vrahnas C, Sims NA. EphrinB2 Signalling in Osteoblast Differentiation, Bone Formation and Endochondral Ossification. ACTA ACUST UNITED AC 2015. [DOI: 10.1007/s40610-015-0024-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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32
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Xiong J, Piemontese M, Onal M, Campbell J, Goellner JJ, Dusevich V, Bonewald L, Manolagas SC, O’Brien CA. Osteocytes, not Osteoblasts or Lining Cells, are the Main Source of the RANKL Required for Osteoclast Formation in Remodeling Bone. PLoS One 2015; 10:e0138189. [PMID: 26393791 PMCID: PMC4578942 DOI: 10.1371/journal.pone.0138189] [Citation(s) in RCA: 208] [Impact Index Per Article: 23.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2015] [Accepted: 08/26/2015] [Indexed: 01/17/2023] Open
Abstract
The cytokine receptor activator of nuclear factor kappa B ligand (RANKL), encoded by the Tnfsf11 gene, is essential for osteoclastogenesis and previous studies have shown that deletion of the Tnfsf11 gene using a Dmp1-Cre transgene reduces osteoclast formation in cancellous bone by more than 70%. However, the Dmp1-Cre transgene used in those studies leads to recombination in osteocytes, osteoblasts, and lining cells making it unclear whether one or more of these cell types produce the RANKL required for osteoclast formation in cancellous bone. Because osteoblasts, osteocytes, and lining cells have distinct locations and functions, distinguishing which of these cell types are sources of RANKL is essential for understanding the orchestration of bone remodeling. To distinguish between these possibilities, we have now created transgenic mice expressing the Cre recombinase under the control of regulatory elements of the Sost gene, which is expressed in osteocytes but not osteoblasts or lining cells in murine bone. Activity of the Sost-Cre transgene in osteocytes, but not osteoblast or lining cells, was confirmed by crossing Sost-Cre transgenic mice with tdTomato and R26R Cre-reporter mice, which express tdTomato fluorescent protein or LacZ, respectively, only in cells expressing the Cre recombinase or their descendants. Deletion of the Tnfsf11 gene in Sost-Cre mice led to a threefold decrease in osteoclast number in cancellous bone and increased cancellous bone mass, mimicking the skeletal phenotype of mice in which the Tnfsf11 gene was deleted using the Dmp1-Cre transgene. These results demonstrate that osteocytes, not osteoblasts or lining cells, are the main source of the RANKL required for osteoclast formation in remodeling cancellous bone.
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Affiliation(s)
- Jinhu Xiong
- Center for Osteoporosis and Metabolic Bone Diseases, University of Arkansas for Medical Sciences, Little Rock, Arkansas, United States of America
- The Central Arkansas Veterans Healthcare System, Little Rock, Arkansas, United States of America
| | - Marilina Piemontese
- Center for Osteoporosis and Metabolic Bone Diseases, University of Arkansas for Medical Sciences, Little Rock, Arkansas, United States of America
- The Central Arkansas Veterans Healthcare System, Little Rock, Arkansas, United States of America
| | - Melda Onal
- Center for Osteoporosis and Metabolic Bone Diseases, University of Arkansas for Medical Sciences, Little Rock, Arkansas, United States of America
- The Central Arkansas Veterans Healthcare System, Little Rock, Arkansas, United States of America
| | - Josh Campbell
- Center for Osteoporosis and Metabolic Bone Diseases, University of Arkansas for Medical Sciences, Little Rock, Arkansas, United States of America
- The Central Arkansas Veterans Healthcare System, Little Rock, Arkansas, United States of America
| | - Joseph J. Goellner
- Center for Osteoporosis and Metabolic Bone Diseases, University of Arkansas for Medical Sciences, Little Rock, Arkansas, United States of America
- The Central Arkansas Veterans Healthcare System, Little Rock, Arkansas, United States of America
| | - Vladimir Dusevich
- Department of Oral Biology, University of Missouri-Kansas City School of Dentistry, Kansas City, Missouri, United States of America
| | - Lynda Bonewald
- Department of Oral Biology, University of Missouri-Kansas City School of Dentistry, Kansas City, Missouri, United States of America
| | - Stavros C. Manolagas
- Center for Osteoporosis and Metabolic Bone Diseases, University of Arkansas for Medical Sciences, Little Rock, Arkansas, United States of America
- The Central Arkansas Veterans Healthcare System, Little Rock, Arkansas, United States of America
| | - Charles A. O’Brien
- Center for Osteoporosis and Metabolic Bone Diseases, University of Arkansas for Medical Sciences, Little Rock, Arkansas, United States of America
- The Central Arkansas Veterans Healthcare System, Little Rock, Arkansas, United States of America
- * E-mail:
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34
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Wallace JM, Bone HG. Effects of estrogen depletion and drug treatment on collagen microstructure: implications. BONEKEY REPORTS 2015; 4:698. [PMID: 26069735 DOI: 10.1038/bonekey.2015.67] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Joseph M Wallace
- Department of Biomedical Engineering, Indiana University-Purdue University at Indianapolis , Indianapolis, IN, USA ; Department of Orthopaedic Surgery, Indiana University School of Medicine , Indianapolis, IN, USA
| | - Henry G Bone
- Michigan Bone and Mineral Clinic , Detroit, MI, USA
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