1
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Stegen S, Carmeliet G. Metabolic regulation of skeletal cell fate and function. Nat Rev Endocrinol 2024; 20:399-413. [PMID: 38499689 DOI: 10.1038/s41574-024-00969-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 02/23/2024] [Indexed: 03/20/2024]
Abstract
Bone development and bone remodelling during adult life are highly anabolic processes requiring an adequate supply of oxygen and nutrients. Bone-forming osteoblasts and bone-resorbing osteoclasts interact closely to preserve bone mass and architecture and are often located close to blood vessels. Chondrocytes within the developing growth plate ensure that bone lengthening occurs before puberty, but these cells function in an avascular environment. With ageing, numerous bone marrow adipocytes appear, often with negative effects on bone properties. Many studies have now indicated that skeletal cells have specific metabolic profiles that correspond to the nutritional microenvironment and their stage-specific functions. These metabolic networks provide not only skeletal cells with sufficient energy, but also biosynthetic intermediates that are necessary for proliferation and extracellular matrix synthesis. Moreover, these metabolic pathways control redox homeostasis to avoid oxidative stress and safeguard cell survival. Finally, several intracellular metabolites regulate the activity of epigenetic enzymes and thus control the fate and function of skeletal cells. The metabolic profile of skeletal cells therefore not only reflects their cellular state, but can also drive cellular activity. Insight into skeletal cell metabolism will thus not only advance our understanding of skeletal development and homeostasis, but also of skeletal disorders, such as osteoarthritis, diabetic bone disease and bone malignancies.
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Affiliation(s)
- Steve Stegen
- Laboratory of Clinical and Experimental Endocrinology, Department of Chronic Diseases and Metabolism, KU Leuven, Leuven, Belgium
| | - Geert Carmeliet
- Laboratory of Clinical and Experimental Endocrinology, Department of Chronic Diseases and Metabolism, KU Leuven, Leuven, Belgium.
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2
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van Dijk Christiansen P, Andreasen CM, El-Masri BM, Laursen KS, Delaisse JM, Andersen TL. Osteoprogenitor recruitment and differentiation during intracortical bone remodeling of adolescent humans. Bone 2023; 177:116896. [PMID: 37699496 DOI: 10.1016/j.bone.2023.116896] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Revised: 08/17/2023] [Accepted: 09/08/2023] [Indexed: 09/14/2023]
Abstract
BACKGROUND Recruitment and proliferation of osteoprogenitors during the reversal-resorption phase, and their differentiation into mature bone-forming osteoblasts is crucial for initiation of bone formation during bone remodeling. This study investigates the osteoprogenitors' gradual recruitment, proliferation, and differentiation into bone-forming osteoblasts within intracortical remodeling events of healthy adolescent humans. METHODS The study was conducted on cortical bone specimens from 11 adolescent human controls - patients undergoing surgery due to coxa valga. The osteoprogenitor recruitment route and differentiation into osteoblasts were backtracked using immunostainings and in situ hybridizations with osteoblastic markers (CD271/NGFR, osterix/SP7, COL3A1 and COL1A1). The osteoblastic cell populations were defined based on the pore surfaces, and their proliferation index (Ki67), density and number/circumference were estimated in multiplex-immunofluorescence (Ki67, TRAcP, CD34) stained sections. RESULTS During the reversal-resorption phase, osteoclasts are intermixed with (COL3A1+NFGR+) osteoblastic reversal cells, which are considered to be osteoprogenitors of (COL1A1+SP7+) bone-forming osteoblasts. Initiation of bone formation requires a critical density of these osteoprogenitors (43 ± 9 cells/mm), which is reached though proliferation (4.4 ± 0.5 % proliferative) and even more so through recruitment of osteoprogenitors, but challenged by the ongoing expansion of the canal circumference. These osteoprogenitors most likely originate from osteoblastic bone lining cells and mainly lumen osteoprogenitors, which expand their population though proliferation (4.6 ± 0.3 %) and vascular recruitment. These lumen osteoprogenitors resemble canopy cells above trabecular remodeling sites, and like canopy cells they extend above bone-forming osteoblasts where they may rejuvenate the osteoblast population during bone formation. CONCLUSION Initiation of bone formation during intracortical remodeling requires a critical density of osteoprogenitors on eroded surfaces, which is reached though proliferation and recruitment of local osteoprogenitors: bone lining cells and lumen osteoprogenitors.
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Affiliation(s)
- Pernille van Dijk Christiansen
- Clinical Cell Biology, Research Unit of Pathology, Department of Pathology, Odense University Hospital and Department of Clinical Research, University of Southern Denmark, Odense, Denmark.
| | - Christina Møller Andreasen
- Clinical Cell Biology, Research Unit of Pathology, Department of Pathology, Odense University Hospital and Department of Clinical Research, University of Southern Denmark, Odense, Denmark; Department of Molecular Medicine, University of Southern Denmark, Odense, Denmark; Danish Spatial Imaging Consortium (DanSIC).
| | - Bilal Mohamad El-Masri
- Clinical Cell Biology, Research Unit of Pathology, Department of Pathology, Odense University Hospital and Department of Clinical Research, University of Southern Denmark, Odense, Denmark; Danish Spatial Imaging Consortium (DanSIC).
| | - Kaja Søndergaard Laursen
- Department of Forensic Medicine, Aarhus University, Aarhus, Denmark; Danish Spatial Imaging Consortium (DanSIC).
| | - Jean-Marie Delaisse
- Clinical Cell Biology, Research Unit of Pathology, Department of Pathology, Odense University Hospital and Department of Clinical Research, University of Southern Denmark, Odense, Denmark; Department of Molecular Medicine, University of Southern Denmark, Odense, Denmark.
| | - Thomas Levin Andersen
- Clinical Cell Biology, Research Unit of Pathology, Department of Pathology, Odense University Hospital and Department of Clinical Research, University of Southern Denmark, Odense, Denmark; Department of Molecular Medicine, University of Southern Denmark, Odense, Denmark; Department of Forensic Medicine, Aarhus University, Aarhus, Denmark; Danish Spatial Imaging Consortium (DanSIC).
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3
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Martin TJ, Seeman E. Bone Remodeling and Modeling: Cellular Targets for Antiresorptive and Anabolic Treatments, Including Approaches Through the Parathyroid Hormone (PTH)/PTH-Related Protein Pathway. Neurospine 2023; 20:1097-1109. [PMID: 38171279 PMCID: PMC10762382 DOI: 10.14245/ns.2346966.483] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Revised: 12/13/2023] [Accepted: 12/14/2023] [Indexed: 01/05/2024] Open
Abstract
Bone is continuously in a state of building and renewal, though the process of remodeling that takes place at many sites asynchronously throughout the skeleton, with bone formation and resorption equal at these sites (bone multicellular units). Remodeling takes place on bone surfaces, both on trabeculae and in the cortex, and serves the purposes of replacing old bone or that damaged by microfractures throughout the skeleton. The bone loss and consequent osteoporotic fractures that result from excess resorption over formation have mainly been prevented or treated by antiresorptive drugs that inhibit osteoclast formation and/or activity. Virtually all of the evidence leading to acceptance of antiresorptive drugs as treatment has depended upon their prevention of vertebral fractures. In recent decades, new prospects came of anabolic treatments that partly restore bone volume and microstructure restore bone that has been lost. The first of these was parathyroid hormone (PTH), shown by daily injection to increase markers of bone formation and prevent fractures. This field of interest enlarged with the discovery of PTH-related protein (PTHrP), so closely related in structure and action to PTH. The structural relationship between PTH and PTHrP is important in assessing their physiological and pharmacological roles, with the N-terminal domains of the 2 having virtually equal actions on target cells. Abaloparatide, a peptide analogue based on the structures of PTHrP and PTH, has been approved in some countries as a therapy for osteoporosis. Treatment through the PTH receptor activation pathway, and probably with any anabolic therapy, needs to be followed by antiresorptive treatment in order to maintain bone that has been restored. No matter how effective anabolic therapies for the skeleton become, it seems highly likely that there will be a continuing need for antiresorptive drugs.
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Affiliation(s)
- Thomas John Martin
- Department of Medicine and St. Vincent’s Institute of Medical Research, University of Melbourne, Melbourne, Australia
| | - Ego Seeman
- Department of Endocrinology and Medicine, Austin Health, University of Melbourne, Melbourne, Australia
- Mary MacKillop Institute of Health Research, Australian Catholic University, Melbourne, Australia
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4
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Sørensen NN, Andreasen CM, Jensen PR, Hauge EM, Bollerslev J, Delaissé JM, Kassem M, Jafari A, Diaz-delCastillo M, Andersen TL. Disturbed bone marrow adiposity in patients with Cushing's syndrome and glucocorticoid- and postmenopausal- induced osteoporosis. Front Endocrinol (Lausanne) 2023; 14:1232574. [PMID: 37881495 PMCID: PMC10597666 DOI: 10.3389/fendo.2023.1232574] [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: 05/31/2023] [Accepted: 09/19/2023] [Indexed: 10/27/2023] Open
Abstract
Background Skeletal stem/progenitor cells (SSPCs) in the bone marrow can differentiate into osteoblasts or adipocytes in response to microenvironmental signalling input, including hormonal signalling. Glucocorticoids (GC) are corticosteroid hormones that promote adipogenic differentiation and are endogenously increased in patients with Cushing´s syndrome (CS). Here, we investigate bone marrow adiposity changes in response to endogenous or exogenous GC increases. For that, we characterize bone biopsies from patients with CS and post-menopausal women with glucocorticoid-induced osteoporosis (GC-O), compared to age-matched controls, including postmenopausal osteoporotic patients (PM-O). Methods Transiliac crest bone biopsies from CS patients and healthy controls, and from postmenopausal women with GC-O and matched controls were analysed; an additional cohort included biopsies from women with PM-O. Plastic-embedded biopsies were sectioned for histomorphometric characterization and quantification of adipocytes. The fraction of adipocyte area per tissue (Ad.Ar/T.Ar) and marrow area (Ad.Ar/Ma.Ar), mean adipocyte profile area (Ad.Pf.Ar) and adipocyte profile density (N.Ad.Pf/Ma.Ar) were determined and correlated to steroid levels. Furthermore, the spatial distribution of adipocytes in relation to trabecular bone was characterized and correlations between bone marrow adiposity and bone remodeling parameters investigated. Results Biopsies from patients with CS and GC-O presented increased Ad.Ar/Ma.Ar, along with adipocyte hypertrophy and hyperplasia. In patients with CS, both Ad.Ar/Ma.Ar and Ad.Pf.Ar significantly correlated with serum cortisol levels. Spatial distribution analyses revealed that, in CS, the increase in Ad.Ar/Ma.Ar near to trabecular bone (<100 µm) was mediated by both adipocyte hypertrophy and hyperplasia, while N.Ad.Pf/Ma.Ar further into the marrow (>100 µm) remained unchanged. In contrast, patients with GC-O only presented increased Ad.Ar/Ma.Ar and mean Ad.Pf.Ar>100 µm from trabecular bone surface, highlighting the differential effect of increased endogenous steroid accumulation. Finally, the Ad.Ar/Ma.Ar and Ad.Ar/T.Ar correlated with the canopy coverage above remodeling events. Conclusion Increased cortisol production in patients with CS induces increased bone marrow adiposity, primarily mediated by adipocyte hypertrophy. This adiposity is particularly evident near trabecular bone surfaces, where hyperplasia also occurs. The differential pattern of adiposity in patients with CS and GC-O highlights that bone marrow adipocytes and their progenitors may respond differently in these two GC-mediated bone diseases.
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Affiliation(s)
- Nina N. Sørensen
- Research Unit of Pathology, Department of Clinical Research, University of Southern Denmark, Odense, Denmark
- Department of Pathology, Odense University Hospital, Odense, Denmark
- Department of Molecular Medicine, University of Southern Denmark, Odense, Denmark
| | - Christina M. Andreasen
- Research Unit of Pathology, Department of Clinical Research, University of Southern Denmark, Odense, Denmark
- Department of Pathology, Odense University Hospital, Odense, Denmark
- Department of Molecular Medicine, University of Southern Denmark, Odense, Denmark
- Danish Spatial Imaging Consortium (DanSIC), Denmark
| | - Pia R. Jensen
- Clinical Cell Biology (KCB), Vejle/Lillebaelt Hospital, Institute of Regional Health Research (IRS), University of Southern Denmark, Vejle, Denmark
| | - Ellen M. Hauge
- Department of Rheumatology, Aarhus University Hospital, Aarhus, Denmark
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Jens Bollerslev
- Section of Specialized Endocrinology, Oslo University Hospital, Oslo, Norway
- Faculty of Medicine, University of Oslo, Oslo, Norway
| | - Jean-Marie Delaissé
- Research Unit of Pathology, Department of Clinical Research, University of Southern Denmark, Odense, Denmark
- Department of Pathology, Odense University Hospital, Odense, Denmark
- Department of Molecular Medicine, University of Southern Denmark, Odense, Denmark
| | - Moustapha Kassem
- Department of Cellular and Molecular Medicine, Novo Nordisk Foundation Center for Stem Cell Biology (DanStem), University of Copenhagen, Copenhagen, Denmark
- Molecular Endocrinology & Stem Cell Research Unit (KMEB), Department of Endocrinology and Metabolism, Odense University Hospital & University of Southern Denmark, Odense, Denmark
| | - Abbas Jafari
- Department of Cellular and Molecular Medicine, Novo Nordisk Foundation Center for Stem Cell Biology (DanStem), University of Copenhagen, Copenhagen, Denmark
- Molecular Endocrinology & Stem Cell Research Unit (KMEB), Department of Endocrinology and Metabolism, Odense University Hospital & University of Southern Denmark, Odense, Denmark
| | - Marta Diaz-delCastillo
- Danish Spatial Imaging Consortium (DanSIC), Denmark
- Department of Forensic Medicine, Aarhus University, Aarhus, Denmark
| | - Thomas L. Andersen
- Research Unit of Pathology, Department of Clinical Research, University of Southern Denmark, Odense, Denmark
- Department of Pathology, Odense University Hospital, Odense, Denmark
- Department of Molecular Medicine, University of Southern Denmark, Odense, Denmark
- Danish Spatial Imaging Consortium (DanSIC), Denmark
- Department of Forensic Medicine, Aarhus University, Aarhus, Denmark
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Andreasen CM, El-Masri BM, MacDonald B, Laursen KS, Nielsen MH, Thomsen JS, Delaisse JM, Andersen TL. Local coordination between intracortical bone remodeling and vascular development in human juvenile bone. Bone 2023; 173:116787. [PMID: 37150243 DOI: 10.1016/j.bone.2023.116787] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Revised: 05/02/2023] [Accepted: 05/02/2023] [Indexed: 05/09/2023]
Abstract
Although failure to establish a vascular network has been associated with many skeletal disorders, little is known about what drives development of vasculature in the intracortical bone compartments. Here, we show that intracortical bone resorption events are coordinated with development of the vasculature. We investigated the prevalence of vascular structures at different remodeling stages as well as their 3D organization using proximal femoral cortical bone from 5 girls and 6 boys (aged 6-15 years). A 2D analysis revealed that non-quiescent intracortical pores contained more vascular structures than quiescent pores (p < 0.0001). Type 2 pores, i.e., remodeling of existing pores, had a higher density of vascular structures than type 1 pores, i.e., de novo created pores (p < 0.05). Furthermore, pores at the eroded-formative remodeling stage, had more vascular structures than pores at any other remodeling stage (p < 0.05). A 3D reconstruction of an intracortical remodeling event showed that osteoclasts in the advancing tip of the cutting cone as well as preosteoclasts in the lumen expressed vascular endothelial growth factor-A (VEGFA), while VEGFA-receptors 1 and 2 mainly were expressed in endothelial cells in the adjacent vasculature. Consequently, we propose that the progression of the vascular network in intracortical remodeling events is driven by osteoclasts expressing VEGFA. Moreover, the vasculature is continuously reconfigured according to the demands of the remodeling events at the surrounding bone surfaces.
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Affiliation(s)
- Christina Møller Andreasen
- Department of Pathology, Odense University Hospital, Odense, Denmark; Molecular Bone Histology lab, Pathology Research Unit, Department of Clinical Research, University of Southern Denmark, Denmark; Department of Molecular Medicine, University of Southern Denmark, Denmark.
| | - Bilal Mohamad El-Masri
- Department of Pathology, Odense University Hospital, Odense, Denmark; Molecular Bone Histology lab, Pathology Research Unit, Department of Clinical Research, University of Southern Denmark, Denmark; Department of Molecular Medicine, University of Southern Denmark, Denmark.
| | - Birgit MacDonald
- Department of Pathology, Odense University Hospital, Odense, Denmark; Molecular Bone Histology lab, Pathology Research Unit, Department of Clinical Research, University of Southern Denmark, Denmark; Clinical Cell Biology, Vejle Hospital - Lillebaelt Hospital, Institute of Regional Health Research, University of Southern Denmark, Denmark
| | - Kaja Søndergaard Laursen
- Clinical Cell Biology, Vejle Hospital - Lillebaelt Hospital, Institute of Regional Health Research, University of Southern Denmark, Denmark; Molecular Bone Histology lab, Department of Forensic Medicine, Aarhus University, Aarhus, Denmark.
| | - Malene Hykkelbjerg Nielsen
- Department of Pathology, Odense University Hospital, Odense, Denmark; Molecular Bone Histology lab, Pathology Research Unit, Department of Clinical Research, University of Southern Denmark, Denmark; Department of Molecular Medicine, University of Southern Denmark, Denmark.
| | | | - Jean-Marie Delaisse
- Department of Pathology, Odense University Hospital, Odense, Denmark; Molecular Bone Histology lab, Pathology Research Unit, Department of Clinical Research, University of Southern Denmark, Denmark; Department of Molecular Medicine, University of Southern Denmark, Denmark; Clinical Cell Biology, Vejle Hospital - Lillebaelt Hospital, Institute of Regional Health Research, University of Southern Denmark, Denmark.
| | - Thomas Levin Andersen
- Department of Pathology, Odense University Hospital, Odense, Denmark; Molecular Bone Histology lab, Pathology Research Unit, Department of Clinical Research, University of Southern Denmark, Denmark; Department of Molecular Medicine, University of Southern Denmark, Denmark; Clinical Cell Biology, Vejle Hospital - Lillebaelt Hospital, Institute of Regional Health Research, University of Southern Denmark, Denmark; Molecular Bone Histology lab, Department of Forensic Medicine, Aarhus University, Aarhus, Denmark.
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6
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Bone marrow MR perfusion imaging and potential for tumor evaluation. Skeletal Radiol 2023; 52:477-491. [PMID: 36271181 DOI: 10.1007/s00256-022-04202-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Revised: 09/19/2022] [Accepted: 10/04/2022] [Indexed: 02/02/2023]
Abstract
The physiology of bone perfusion is reviewed outlining how it can be measured with dynamic contrast-enhanced MRI as well as intravoxel incoherent imaging. Evaluation of bone perfusion provides a potential means of assessing tumor activity and treatment response beyond that possible with standard MR imaging.
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7
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Bolamperti S, Villa I, Rubinacci A. Bone remodeling: an operational process ensuring survival and bone mechanical competence. Bone Res 2022; 10:48. [PMID: 35851054 PMCID: PMC9293977 DOI: 10.1038/s41413-022-00219-8] [Citation(s) in RCA: 91] [Impact Index Per Article: 45.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Revised: 05/02/2022] [Accepted: 05/15/2022] [Indexed: 12/12/2022] Open
Abstract
Bone remodeling replaces old and damaged bone with new bone through a sequence of cellular events occurring on the same surface without any change in bone shape. It was initially thought that the basic multicellular unit (BMU) responsible for bone remodeling consists of osteoclasts and osteoblasts functioning through a hierarchical sequence of events organized into distinct stages. However, recent discoveries have indicated that all bone cells participate in BMU formation by interacting both simultaneously and at different differentiation stages with their progenitors, other cells, and bone matrix constituents. Therefore, bone remodeling is currently considered a physiological outcome of continuous cellular operational processes optimized to confer a survival advantage. Bone remodeling defines the primary activities that BMUs need to perform to renew successfully bone structural units. Hence, this review summarizes the current understanding of bone remodeling and future research directions with the aim of providing a clinically relevant biological background with which to identify targets for therapeutic strategies in osteoporosis.
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Affiliation(s)
- Simona Bolamperti
- Osteoporosis and Bone and Mineral Metabolism Unit, IRCCS San Raffaele Hospital, Via Olgettina 60, 20132, Milano, Italy
| | - Isabella Villa
- Osteoporosis and Bone and Mineral Metabolism Unit, IRCCS San Raffaele Hospital, Via Olgettina 60, 20132, Milano, Italy
| | - Alessandro Rubinacci
- Osteoporosis and Bone and Mineral Metabolism Unit, IRCCS San Raffaele Hospital, Via Olgettina 60, 20132, Milano, Italy.
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8
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Burger MG, Grosso A, Briquez PS, Born GME, Lunger A, Schrenk F, Todorov A, Sacchi V, Hubbell JA, Schaefer DJ, Banfi A, Di Maggio N. Robust coupling of angiogenesis and osteogenesis by VEGF-decorated matrices for bone regeneration. Acta Biomater 2022; 149:111-125. [PMID: 35835287 DOI: 10.1016/j.actbio.2022.07.014] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Revised: 06/13/2022] [Accepted: 07/06/2022] [Indexed: 12/11/2022]
Abstract
Rapid vascularization of clinical-size bone grafts is an unsolved challenge in regenerative medicine. Vascular endothelial growth factor-A (VEGF) is the master regulator of angiogenesis. Its over-expression by genetically modified human osteoprogenitors has been previously evaluated to drive vascularization in osteogenic grafts, but has been observed to cause paradoxical bone loss through excessive osteoclast recruitment. However, during bone development angiogenesis and osteogenesis are physiologically coupled by VEGF expression. Here we investigated whether the mode of VEGF delivery may be a key to recapitulate its physiological function. VEGF activity requires binding to the extracellular matrix, and heterogeneous levels of expression lead to localized microenvironments of excessive dose. Therefore we hypothesized that a homogeneous distribution of matrix-associated factor in the microenvironment may enable efficient coupling of angiogenesis and bone formation. This was achieved by decorating fibrin matrices with a cross-linkable engineered version of VEGF (TG-VEGF) that is released only by enzymatic cleavage by invading cells. In ectopic grafts, both TG-VEGF and VEGF-expressing progenitors similarly improved vascularization within the first week, but efficient bone formation was possible only in the factor-decorated matrices, whereas heterogenous, cell-based VEGF expression caused significant bone loss. In critical-size orthotopic calvaria defects, TG-VEGF effectively improved early vascular invasion, osteoprogenitor survival and differentiation, as well as bone repair compared to both controls and VEGF-expressing progenitors. In conclusion, homogenous distribution of matrix-associated VEGF protein preserves the physiological coupling of angiogenesis and osteogenesis, providing an attractive and clinically applicable strategy to engineer vascularized bone. STATEMENT OF SIGNIFICANCE: The therapeutic regeneration of vascularized bone is an unsolved challenge in regenerative medicine. Stimulation of blood vessel growth by over-expression of VEGF has been associated with paradoxical bone loss, whereas angiogenesis and osteogenesis are physiologically coupled by VEGF during development. Here we found that controlling the distribution of VEGF dose in an osteogenic graft is key to recapitulate its physiological function. In fact, homogeneous decoration of fibrin matrices with engineered VEGF could improve both vascularization and bone formation in orthotopic critical-size defects, dispensing with the need for combined osteogenic factor delivery. VEGF-decorated fibrin matrices provide a readily translatable platform for engineering a controlled microenvironment for bone regeneration.
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Affiliation(s)
- Maximilian G Burger
- Cell and Gene Therapy, Department of Biomedicine, Basel University Hospital and University of Basel, Hebelstrasse 20, 4031, Basel, Switzerland; Department of Plastic, Reconstructive, Aesthetic and Hand Surgery, Basel University Hospital, Petersgraben 4, 4031, Basel, Switzerland
| | - Andrea Grosso
- Cell and Gene Therapy, Department of Biomedicine, Basel University Hospital and University of Basel, Hebelstrasse 20, 4031, Basel, Switzerland
| | - Priscilla S Briquez
- Pritzker School of Molecular Engineering, University of Chicago, 5640 S Ellis Ave, Chicago, IL 60637, USA
| | - Gordian M E Born
- Tissue Engineering, Department of Biomedicine, Basel University Hospital and University of Basel, Hebelstrasse 20, 4031, Basel, Switzerland
| | - Alexander Lunger
- Cell and Gene Therapy, Department of Biomedicine, Basel University Hospital and University of Basel, Hebelstrasse 20, 4031, Basel, Switzerland; Department of Plastic, Reconstructive, Aesthetic and Hand Surgery, Basel University Hospital, Petersgraben 4, 4031, Basel, Switzerland
| | - Flavio Schrenk
- Cell and Gene Therapy, Department of Biomedicine, Basel University Hospital and University of Basel, Hebelstrasse 20, 4031, Basel, Switzerland
| | - Atanas Todorov
- Department of Plastic, Reconstructive, Aesthetic and Hand Surgery, Basel University Hospital, Petersgraben 4, 4031, Basel, Switzerland; Tissue Engineering, Department of Biomedicine, Basel University Hospital and University of Basel, Hebelstrasse 20, 4031, Basel, Switzerland
| | - Veronica Sacchi
- Cell and Gene Therapy, Department of Biomedicine, Basel University Hospital and University of Basel, Hebelstrasse 20, 4031, Basel, Switzerland
| | - Jeffrey A Hubbell
- Pritzker School of Molecular Engineering, University of Chicago, 5640 S Ellis Ave, Chicago, IL 60637, USA
| | - Dirk J Schaefer
- Cell and Gene Therapy, Department of Biomedicine, Basel University Hospital and University of Basel, Hebelstrasse 20, 4031, Basel, Switzerland; Department of Plastic, Reconstructive, Aesthetic and Hand Surgery, Basel University Hospital, Petersgraben 4, 4031, Basel, Switzerland
| | - Andrea Banfi
- Cell and Gene Therapy, Department of Biomedicine, Basel University Hospital and University of Basel, Hebelstrasse 20, 4031, Basel, Switzerland; Department of Plastic, Reconstructive, Aesthetic and Hand Surgery, Basel University Hospital, Petersgraben 4, 4031, Basel, Switzerland.
| | - Nunzia Di Maggio
- Cell and Gene Therapy, Department of Biomedicine, Basel University Hospital and University of Basel, Hebelstrasse 20, 4031, Basel, Switzerland.
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Thorny ground, rocky soil: Tissue-specific mechanisms of tumor dormancy and relapse. Semin Cancer Biol 2022; 78:104-123. [PMID: 33979673 PMCID: PMC9595433 DOI: 10.1016/j.semcancer.2021.05.007] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Revised: 04/30/2021] [Accepted: 05/04/2021] [Indexed: 02/07/2023]
Abstract
Disseminated tumor cells (DTCs) spread systemically yet distinct patterns of metastasis indicate a range of tissue susceptibility to metastatic colonization. Distinctions between permissive and suppressive tissues are still being elucidated at cellular and molecular levels. Although there is a growing appreciation for the role of the microenvironment in regulating metastatic success, we have a limited understanding of how diverse tissues regulate DTC dormancy, the state of reversible quiescence and subsequent awakening thought to contribute to delayed relapse. Several themes of microenvironmental regulation of dormancy are beginning to emerge, including vascular association, co-option of pre-existing niches, metabolic adaptation, and immune evasion, with tissue-specific nuances. Conversely, DTC awakening is often associated with injury or inflammation-induced activation of the stroma, promoting a proliferative environment with DTCs following suit. We review what is known about tissue-specific regulation of tumor dormancy on a tissue-by-tissue basis, profiling major metastatic organs including the bone, lung, brain, liver, and lymph node. An aerial view of the barriers to metastatic growth may reveal common targets and dependencies to inform the therapeutic prevention of relapse.
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10
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Chavassieux P, Chapurlat R. Interest of Bone Histomorphometry in Bone Pathophysiology Investigation: Foundation, Present, and Future. Front Endocrinol (Lausanne) 2022; 13:907914. [PMID: 35966102 PMCID: PMC9368205 DOI: 10.3389/fendo.2022.907914] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Accepted: 06/22/2022] [Indexed: 11/13/2022] Open
Abstract
Despite the development of non-invasive methods, bone histomorphometry remains the only method to analyze bone at the tissue and cell levels. Quantitative analysis of transiliac bone sections requires strict methodologic conditions but since its foundation more 60 years ago, this methodology has progressed. Our purpose was to review the evolution of bone histomorphometry over the years and its contribution to the knowledge of bone tissue metabolism under normal and pathological conditions and the understanding of the action mechanisms of therapeutic drugs in humans. The two main applications of bone histomorphometry are the diagnosis of bone diseases and research. It is warranted for the diagnosis of mineralization defects as in osteomalacia, of other causes of osteoporosis as bone mastocytosis, or the classification of renal osteodystrophy. Bone biopsies are required in clinical trials to evaluate the safety and mechanism of action of new therapeutic agents and were applied to anti-osteoporotic agents such as bisphosphonates and denosumab, an anti-RANKL, which induces a marked reduction of the bone turnover with a consequent elongation of the mineralization period. In contrast, an increased bone turnover with an extension of the formation site is observed with teriparatide. Romosozumab, an anti-sclerostin, has a dual effect with an early increased formation and reduced resorption. Bone histomorphometric studies allow us to understand the mechanism of coupling between formation and resorption and to evaluate the respective role of bone modeling and remodeling. The adaptation of new image analysis techniques will help bone biopsy analysis in the future.
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11
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Sun Y, Li J, Xie X, Gu F, Sui Z, Zhang K, Yu T. Recent Advances in Osteoclast Biological Behavior. Front Cell Dev Biol 2021; 9:788680. [PMID: 34957116 PMCID: PMC8694526 DOI: 10.3389/fcell.2021.788680] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Accepted: 11/15/2021] [Indexed: 12/19/2022] Open
Abstract
With the progress of the aging population, bone-related diseases such as osteoporosis and osteoarthritis have become urgent problems. Recent studies have demonstrated the importance of osteoclasts in bone homeostasis, implying these will be an important mediator in the treatment of bone-related diseases. Up to now, several reviews have been performed on part of osteoclast biological behaviors such as differentiation, function, or apoptosis. However, few reviews have shown the complete osteoclast biology and research advances in recent years. Therefore, in this review, we focus on the origin, differentiation, apoptosis, behavior changes and coupling signals with osteoblasts, providing a simple but comprehensive overview of osteoclasts for subsequent studies.
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Affiliation(s)
- Yang Sun
- Department of Orthopedics, The First Hospital of Jilin University, Changchun, China
| | - Jiangbi Li
- Department of Orthopedics, The First Hospital of Jilin University, Changchun, China
| | - Xiaoping Xie
- Department of Orthopedics, The First Hospital of Jilin University, Changchun, China
| | - Feng Gu
- Department of Orthopedics, The First Hospital of Jilin University, Changchun, China
| | - Zhenjiang Sui
- Department of Orthopedics, The First Hospital of Jilin University, Changchun, China
| | - Ke Zhang
- Department of Orthopedics, The First Hospital of Jilin University, Changchun, China
| | - Tiecheng Yu
- Department of Orthopedics, The First Hospital of Jilin University, Changchun, China
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12
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Meertens R, Knapp KM, Strain WD, Casanova F, Ball S, Fulford J, Thorn C. In vivo Measurement of Intraosseous Vascular Haemodynamic Markers in Human Bone Tissue Utilising Near Infrared Spectroscopy. Front Physiol 2021; 12:738239. [PMID: 34630158 PMCID: PMC8497693 DOI: 10.3389/fphys.2021.738239] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Accepted: 08/25/2021] [Indexed: 11/13/2022] Open
Abstract
Objective: Poor vascular health is associated with reduced bone strength and increased risk of fragility fracture. However, direct measurement of intraosseous vascular health is difficult due to the density and mineral content of bone. We investigated the feasibility of using a commercially available continuous wave near infrared spectroscopy (NIRS) system for the investigation of vascular haemodynamics in human bone in vivo. Approach: An arterial occlusion (AO) protocol was developed for obtaining haemodynamic measurements of the proximal tibia and lateral calf, including assessment of the protocol’s intra operator reproducibility. For 36 participants, intraosseous haemodynamics derived by NIRS were compared to alternative tests of bone health based on dual x-ray absorptiometry (DXA) testing and MRI. Main Results: Near infrared spectroscopy markers of haemodynamics of the proximal tibia demonstrated acceptable reproducibility, comparable with reproducibility assessments of alternative modalities measuring intraosseous haemodynamics, and the use of NIRS for measuring muscle. Novel associations have been demonstrated between haemodynamic markers of bone measured with NIRS and body composition and bone mineral density (BMD) measurements obtained with both DXA and MRI. Significance: Near infrared spectroscopy provides inexpensive, non-invasive, safe, and real time data on changes in oxygenated and deoxygenated haemoglobin concentration in bone at the proximal tibia. This study has demonstrated the potential for NIRS to contribute to research investigating the pathophysiological role of vascular dysfunction within bone tissue, but also the limitations and need for further development of NIRS technology.
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Affiliation(s)
- Robert Meertens
- College of Medicine and Health, University of Exeter, Exeter, United Kingdom
| | - Karen M Knapp
- College of Medicine and Health, University of Exeter, Exeter, United Kingdom
| | | | - Francesco Casanova
- College of Medicine and Health, University of Exeter, Exeter, United Kingdom
| | - Susan Ball
- NIHR Applied Research Collaboration South West Peninsula (PenARC), College of Medicine and Health, University of Exeter, Exeter, United Kingdom
| | - Jon Fulford
- NIHR Exeter Clinical Research Facility, College of Medicine and Health, University of Exeter, Exeter, United Kingdom
| | - Clare Thorn
- College of Medicine and Health, University of Exeter, Exeter, United Kingdom
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13
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The Cellular Choreography of Osteoblast Angiotropism in Bone Development and Homeostasis. Int J Mol Sci 2021; 22:ijms22147253. [PMID: 34298886 PMCID: PMC8305002 DOI: 10.3390/ijms22147253] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Revised: 06/23/2021] [Accepted: 06/29/2021] [Indexed: 12/11/2022] Open
Abstract
Interaction between endothelial cells and osteoblasts is essential for bone development and homeostasis. This process is mediated in large part by osteoblast angiotropism, the migration of osteoblasts alongside blood vessels, which is crucial for the homing of osteoblasts to sites of bone formation during embryogenesis and in mature bones during remodeling and repair. Specialized bone endothelial cells that form "type H" capillaries have emerged as key interaction partners of osteoblasts, regulating osteoblast differentiation and maturation and ensuring their migration towards newly forming trabecular bone areas. Recent revolutions in high-resolution imaging methodologies for bone as well as single cell and RNA sequencing technologies have enabled the identification of some of the signaling pathways and molecular interactions that underpin this regulatory relationship. Similarly, the intercellular cross talk between endothelial cells and entombed osteocytes that is essential for bone formation, repair, and maintenance are beginning to be uncovered. This is a relatively new area of research that has, until recently, been hampered by a lack of appropriate analysis tools. Now that these tools are available, greater understanding of the molecular relationships between these key cell types is expected to facilitate identification of new drug targets for diseases of bone formation and remodeling.
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14
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Kristensen HB, Andersen TL, Patriarca A, Kallenbach K, MacDonald B, Sikjaer T, Ejersted C, Delaisse JM. Human hematopoietic microenvironments. PLoS One 2021; 16:e0250081. [PMID: 33878141 PMCID: PMC8057613 DOI: 10.1371/journal.pone.0250081] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Accepted: 03/30/2021] [Indexed: 11/18/2022] Open
Abstract
Dormancy of hematopoietic stem cells and formation of progenitors are directed by signals that come from the bone marrow microenvironment. Considerable knowledge has been gained on the murine hematopoietic stem cell microenvironment, while less so on the murine progenitor microenvironment and even less so on these microenvironments in humans. Characterization of these microenvironments is decisive for understanding hematopoiesis and finding new treatment modalities against bone marrow malignancies in the clinic. However, it is equally challenging, because hematopoietic stem cells are difficult to detect in the complex bone marrow landscape. In the present study we are characterizing the human hematopoietic stem cell and progenitor microenvironment. We obtained three adjacent bone marrow sections from ten healthy volunteers. One was used to identify a population of CD34+/CD38- “hematopoietic stem cells and multipotent progenitors” and a population of CD34+/CD38+ “progenitors” based on immunofluorescence pattern/intensity and cellular morphology. The other two were immunostained respectively for CD34/CD56 and for CD34/SMA. Using the combined information we performed a non-computer-assisted quantification of nine bone marrow components (adipocytes, megakaryocytes, bone surfaces, four different vessel types (arteries, capillaries, sinusoids and collecting sinuses), other “hematopoietic stem cells and multipotent progenitors” and other “progenitors”) within 30 μm of “hematopoietic stem cells and multipotent progenitors”, “progenitors”, and “random cell profiles”. We show that the microenvironment of the “hematopoietic stem cells and multipotent progenitors” is significantly enriched in sinusoids and megakaryocytes, while the microenvironment of the “progenitors” is significantly enriched in capillaries, other “progenitors”, bone surfaces and arteries.
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Affiliation(s)
- Helene Bjoerg Kristensen
- Department of Clinical Cell Biology, Institute of Regional Health Science, University of Southern Denmark, Lillebaelt Hospital, Vejle, Denmark
- Department of Pathology, Clinical Cell Biology, Odense University Hospital, Odense, Denmark
- Department of Clinical Research and Department of Molecular Medicine, University of Southern Denmark, Odense, Denmark
- * E-mail:
| | - Thomas Levin Andersen
- Department of Clinical Cell Biology, Institute of Regional Health Science, University of Southern Denmark, Lillebaelt Hospital, Vejle, Denmark
- Department of Pathology, Clinical Cell Biology, Odense University Hospital, Odense, Denmark
- Department of Clinical Research and Department of Molecular Medicine, University of Southern Denmark, Odense, Denmark
- Department of Forensic Medicine, Aarhus University, Aarhus, Denmark
| | - Andrea Patriarca
- Division of Hematology, Department of Oncology, Hospital "Maggiore della Carità", Novara, Italy
| | - Klaus Kallenbach
- Department of Pathology, Zealand University Hospital, Roskilde, Denmark
| | - Birgit MacDonald
- Department of Clinical Cell Biology, Institute of Regional Health Science, University of Southern Denmark, Lillebaelt Hospital, Vejle, Denmark
| | - Tanja Sikjaer
- Department of Endocrinology and Internal Medicine, Aarhus University Hospital, Aarhus, Denmark
| | - Charlotte Ejersted
- Department of Endocrinology, Odense University Hospital, Odense, Denmark
| | - Jean-Marie Delaisse
- Department of Clinical Cell Biology, Institute of Regional Health Science, University of Southern Denmark, Lillebaelt Hospital, Vejle, Denmark
- Department of Pathology, Clinical Cell Biology, Odense University Hospital, Odense, Denmark
- Department of Clinical Research and Department of Molecular Medicine, University of Southern Denmark, Odense, Denmark
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15
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Jensen PR, Andersen TL, Chavassieux P, Roux JP, Delaisse JM. Bisphosphonates impair the onset of bone formation at remodeling sites. Bone 2021; 145:115850. [PMID: 33465485 DOI: 10.1016/j.bone.2021.115850] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Revised: 01/08/2021] [Accepted: 01/15/2021] [Indexed: 12/20/2022]
Abstract
Bisphosphonates are widely used anti-osteoporotic drugs targeting osteoclasts. They strongly inhibit bone resorption, but also strongly reduce bone formation. This reduced formation is commonly ascribed to the mechanism maintaining the resorption/formation balance during remodeling. The present study provides evidence for an additional mechanism where bisphosphonates actually impair the onset of bone formation after resorption. The evidence is based on morphometric parameters recently developed to assess the activities reversing resorption to formation. Herein, we compare these parameters in cancellous bone of alendronate- and placebo-treated postmenopausal osteoporotic patients. Alendronate increases the prevalence of eroded surfaces characterized by reversal cells/osteoprogenitors at low cell density and remote from active bone surfaces. This indicates deficient cell expansion on eroded surfaces - an event that is indispensable to start formation. Furthermore, alendronate decreases the coverage of these eroded surfaces by remodeling compartment canopies, a putative source of reversal cells/osteoprogenitors. Finally, alendronate strongly decreases the activation frequency of bone formation, and decreases more the formative compared to the eroded surfaces. All these parameters correlate with each other. These observations lead to a model where bisphosphonates hamper the osteoprogenitor recruitment required to initiate bone formation. This effect results in a larger eroded surface, thereby explaining the well-known paradox that bisphosphonates strongly inhibit bone resorption without strongly decreasing eroded surfaces. The possible mechanism for hampered osteoprogenitor recruitment is discussed: bisphosphonates may decrease the release of osteogenic factors by the osteoclasts, and/or bisphosphonates released by osteoclasts may act directly on neighboring osteoprogenitor cells as reported in preclinical studies.
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Affiliation(s)
- Pia Rosgaard Jensen
- Clinical Cell Biology, Lillebælt Hospital, Department of Regional Health Research, University of Southern Denmark, Vejle, Denmark.
| | - Thomas Levin Andersen
- Clinical Cell Biology, Lillebælt Hospital, Department of Regional Health Research, University of Southern Denmark, Vejle, Denmark; Clinical Cell Biology, Department of Pathology, Odense University Hospital, Department of Clinical Research, Department of Molecular Medicine, University of Southern Denmark, Odense, Denmark; Department of Forensic Medicine, Aarhus University, Aarhus, Denmark.
| | | | | | - Jean-Marie Delaisse
- Clinical Cell Biology, Lillebælt Hospital, Department of Regional Health Research, University of Southern Denmark, Vejle, Denmark; Clinical Cell Biology, Department of Pathology, Odense University Hospital, Department of Clinical Research, Department of Molecular Medicine, University of Southern Denmark, Odense, Denmark.
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16
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Delaisse JM, Søe K, Andersen TL, Rojek AM, Marcussen N. The Mechanism Switching the Osteoclast From Short to Long Duration Bone Resorption. Front Cell Dev Biol 2021; 9:644503. [PMID: 33859985 PMCID: PMC8042231 DOI: 10.3389/fcell.2021.644503] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Accepted: 02/22/2021] [Indexed: 12/28/2022] Open
Abstract
The current models of osteoclastic bone resorption focus on immobile osteoclasts sitting on the bone surface and drilling a pit into the bone matrix. It recently appeared that many osteoclasts also enlarge their pit by moving across the bone surface while resorbing. Drilling a pit thus represents only the start of a resorption event of much larger amplitude. This prolonged resorption activity significantly contributes to pathological bone destruction, but the mechanism whereby the osteoclast engages in this process does not have an answer within the standard bone resorption models. Herein, we review observations that lead to envision how prolonged resorption is possible through simultaneous resorption and migration. According to the standard pit model, the “sealing zone” which surrounds the ruffled border (i.e., the actual resorption apparatus), “anchors” the ruffled border against the bone surface to be resorbed. Herein, we highlight that continuation of resorption demands that the sealing zone “glides” inside the cavity. Thereby, the sealing zone emerges as the structure responsible for orienting and displacing the ruffled border, e.g., directing resorption against the cavity wall. Importantly, sealing zone displacement stringently requires thorough collagen removal from the cavity wall - which renders strong cathepsin K collagenolysis indispensable for engagement of osteoclasts in cavity-enlargement. Furthermore, the sealing zone is associated with generation of new ruffled border at the leading edge, thereby allowing the ruffled border to move ahead. The sealing zone and ruffled border displacements are coordinated with the migration of the cell body, shown to be under control of lamellipodia at the leading edge and of the release of resorption products at the rear. We propose that bone resorption demands more attention to osteoclastic models integrating resorption and migration activities into just one cell phenotype.
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Affiliation(s)
- Jean-Marie Delaisse
- Clinical Cell Biology, Department of Pathology, Odense University Hospital, Odense, Denmark.,Clinical Cell Biology, Pathology Research Unit, Department of Clinical Research, University of Southern Denmark, Odense, Denmark.,Department of Molecular Medicine, University of Southern Denmark, Odense, Denmark
| | - Kent Søe
- Clinical Cell Biology, Department of Pathology, Odense University Hospital, Odense, Denmark.,Clinical Cell Biology, Pathology Research Unit, Department of Clinical Research, University of Southern Denmark, Odense, Denmark.,Department of Molecular Medicine, University of Southern Denmark, Odense, Denmark
| | - Thomas Levin Andersen
- Clinical Cell Biology, Department of Pathology, Odense University Hospital, Odense, Denmark.,Clinical Cell Biology, Pathology Research Unit, Department of Clinical Research, University of Southern Denmark, Odense, Denmark.,Department of Molecular Medicine, University of Southern Denmark, Odense, Denmark.,Department of Forensic Medicine, Aarhus University, Aarhus, Denmark
| | | | - Niels Marcussen
- Department of Molecular Medicine, University of Southern Denmark, Odense, Denmark
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17
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van Gastel N, Carmeliet G. Metabolic regulation of skeletal cell fate and function in physiology and disease. Nat Metab 2021; 3:11-20. [PMID: 33398192 DOI: 10.1038/s42255-020-00321-3] [Citation(s) in RCA: 54] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Accepted: 11/10/2020] [Indexed: 01/28/2023]
Abstract
The skeleton is diverse in its functions, which include mechanical support, movement, blood cell production, mineral storage and endocrine regulation. This multifaceted role is achieved through an interplay of osteoblasts, chondrocytes, bone marrow adipocytes and stromal cells, all generated from skeletal stem cells. Emerging evidence shows the importance of cellular metabolism in the molecular control of the skeletal system. The different skeletal cell types not only have distinct metabolic demands relating to their particular functions but also are affected by microenvironmental constraints. Specific metabolites control skeletal stem cell maintenance, direct lineage allocation and mediate cellular communication. Here, we discuss recent findings on the roles of cellular metabolism in determining skeletal stem cell fate, coordinating osteoblast and chondrocyte function, and organizing stromal support of haematopoiesis. We also consider metabolic dysregulation in skeletal ageing and degenerative diseases, and provide an outlook on how the field may evolve in the coming years.
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Affiliation(s)
- Nick van Gastel
- de Duve Institute, Brussels, Belgium.
- Department of Stem Cell and Regenerative Biology, Harvard Stem Cell Institute, Harvard University, Cambridge, MA, USA.
| | - Geert Carmeliet
- Laboratory of Clinical and Experimental Endocrinology, Department of Chronic Diseases and Metabolism, KU Leuven, Leuven, Belgium.
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18
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Panvini FM, Pacini S, Mazzoni S, Méndez-Ferrer S. Multicolor Immunofluorescence Staining of Paraffin-Embedded Human Bone Marrow Sections. Methods Mol Biol 2021; 2308:119-126. [PMID: 34057719 DOI: 10.1007/978-1-0716-1425-9_10] [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] [Indexed: 02/11/2024]
Abstract
Immunofluorescence is an indispensable method for the identification, localization and study of the expression of target antigens in formalin-fixed, paraffin-embedded (FFPE) tissue sections of human bone marrow. However, the procedure shows technical limitations because of the chemical and physical treatments required for sample processing before imaging. Here we describe a revisited protocol to obtain high-resolution images of human bone marrow trephine biopsies, improving the antigen-antibody recognition and preserving the morphology and the architecture of the bone marrow microenvironment.
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Affiliation(s)
- Francesca M Panvini
- Institute of Life Sciences, Sant'Anna School of Advanced Studies, Pisa, Italy
| | - Simone Pacini
- Department of Clinical and Experimental Medicine, Hematology Division, University of Pisa, Pisa, Italy
| | - Stefano Mazzoni
- Department of Translational Research and New Technology in Medicine, University of Pisa, Pisa, Italy
| | - Simón Méndez-Ferrer
- Wellcome-MRC Cambridge Stem Cell Institute, Cambridge, UK.
- Department of Haematology, University of Cambridge, Cambridge, UK.
- National Health Service Blood and Transplant, Cambridge, UK.
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19
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Panvini FM, Pacini S, Montali M, Barachini S, Mazzoni S, Morganti R, Ciancia EM, Carnicelli V, Petrini M. High NESTIN Expression Marks the Endosteal Capillary Network in Human Bone Marrow. Front Cell Dev Biol 2020; 8:596452. [PMID: 33364234 PMCID: PMC7753038 DOI: 10.3389/fcell.2020.596452] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Accepted: 11/11/2020] [Indexed: 12/20/2022] Open
Abstract
Hematopoiesis is hosted, supported and regulated by a special bone marrow (BM) microenvironment known as "niche." BM niches have been classified based on micro-anatomic distance from the bone surface into "endosteal" and "central" niches. Whilst different blood vessels have been found in both BM niches in mice, our knowledge of the human BM architecture is much more limited. Here, we have used a combination of markers including NESTIN, CD146, and αSMA labeling different blood vessels in benign human BM. Applying immunohistochemical/immunofluorescence techniques on BM trephines and performing image analysis on almost 300 microphotographs, we detected high NESTIN expression in BM endothelial cells (BMECs) of small arteries (A) and endosteal arterioles (EA), and also in very small vessels we named NESTIN+ capillary-like tubes (NCLTs), not surrounded by sub-endothelial perivascular cells that occasionally reported low levels of NESTIN expression. Statistically, NCLTs were detected within 40 μm from bone trabecula, frequently found in direct contact to the bone line and spatially correlated with hematopoietic stem/progenitor cells. Our results support the expression of NESTIN in human BMECs of EA and A in accordance with the updated classification of murine BM micro-vessels. NCLTs for their peculiar characteristics and micro-anatomical localization have been here proposed as transitional vessels possibly involved in regulating human hematopoiesis.
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Affiliation(s)
- Francesca M. Panvini
- Institute of Life Sciences, Sant’Anna School of Advanced Studies, Pisa, Italy
- Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - Simone Pacini
- Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - Marina Montali
- Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - Serena Barachini
- Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - Stefano Mazzoni
- Department of Translational Research and New Technology in Medicine, University of Pisa, Pisa, Italy
| | - Riccardo Morganti
- Statistical Support to Clinical Trials Department, Azienda Ospedaliero Universitaria Pisana, Pisa, Italy
| | - Eugenio M. Ciancia
- Department of Pathology, Azienda Ospedsaliero Universitaria Pisana, Pisa, Italy
| | - Vittoria Carnicelli
- Department of Surgical, Medical and Molecular Pathology and Critical Care Medicine, University of Pisa, Pisa, Italy
| | - Mario Petrini
- Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
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20
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Delaisse JM, Andersen TL, Kristensen HB, Jensen PR, Andreasen CM, Søe K. Re-thinking the bone remodeling cycle mechanism and the origin of bone loss. Bone 2020; 141:115628. [PMID: 32919109 DOI: 10.1016/j.bone.2020.115628] [Citation(s) in RCA: 66] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Revised: 09/04/2020] [Accepted: 09/04/2020] [Indexed: 02/06/2023]
Abstract
Proper bone remodeling necessarily requires that osteoblasts reconstruct the bone that osteoclasts have resorbed. However, the cellular events connecting resorption to reconstruction have remained poorly known. The consequence is a fragmentary understanding of the remodeling cycle where only the resorption and formation steps are taken into account. New tools have recently made possible to elucidate how resorption shifts to formation, thereby allowing to comprehend the remodeling cycle as a whole. This new knowledge is reviewed herein. It shows how teams of osteoclasts and osteoblast lineage cells are progressively established and how they are subjected therein to reciprocal interactions. Contrary to the common view, osteoclasts and osteoprogenitors are intermingled on the eroded surfaces. The analysis of the resorption and cell population dynamics shows that osteoprogenitor cell expansion and resorption proceed as an integrated mechanism; that a threshold cell density of osteoprogenitors on the eroded surface is mandatory for onset of bone formation; that the cell initiating osteoprogenitor cell expansion is the osteoclast; and that the osteoclast therefore triggers putative osteoprogenitor reservoirs positioned at proximity of the eroded bone surface (bone lining cells, canopy cells, pericytes). The interplay between magnitude of resorption and rate of cell expansion governs how soon bone reconstruction is initiated and may determine uncoupling and permanent bone loss if a threshold cell density is not reached. The clinical perspectives opened by these findings are discussed.
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Affiliation(s)
- Jean-Marie Delaisse
- Clinical Cell Biology, Department of Pathology, Odense University Hospital, Department of Clinical Research, Department of Molecular Medicine, University of Southern Denmark, Odense, Denmark.
| | - Thomas Levin Andersen
- Clinical Cell Biology, Department of Pathology, Odense University Hospital, Department of Clinical Research, Department of Molecular Medicine, University of Southern Denmark, Odense, Denmark; Department of Forensic Medicine, Aarhus University, Aarhus, Denmark.
| | - Helene Bjoerg Kristensen
- Clinical Cell Biology, Lillebælt Hospital, Department of Regional Health Research, University of Southern Denmark, Vejle, Denmark.
| | - Pia Rosgaard Jensen
- Clinical Cell Biology, Lillebælt Hospital, Department of Regional Health Research, University of Southern Denmark, Vejle, Denmark.
| | - Christina Møller Andreasen
- Clinical Cell Biology, Department of Pathology, Odense University Hospital, Department of Clinical Research, Department of Molecular Medicine, University of Southern Denmark, Odense, Denmark.
| | - Kent Søe
- Clinical Cell Biology, Department of Pathology, Odense University Hospital, Department of Clinical Research, Department of Molecular Medicine, University of Southern Denmark, Odense, Denmark.
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21
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Eggers B, Marciniak J, Memmert S, Kramer FJ, Deschner J, Nokhbehsaim M. The beneficial effect of cold atmospheric plasma on parameters of molecules and cell function involved in wound healing in human osteoblast-like cells in vitro. Odontology 2020; 108:607-616. [PMID: 32030565 PMCID: PMC7438292 DOI: 10.1007/s10266-020-00487-y] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Accepted: 01/19/2020] [Indexed: 02/07/2023]
Abstract
The aim of this study was to analyse the effect of cold atmospheric plasma (CAP) on human osteoblast-like cells in vitro. Additionally, underlying intracellular mechanisms were to be studied. Human osteoblast-like (MG63) cells were exposed to CAP for 60 s. The effects of CAP on key molecules essential for the wound healing response were studied using real-time PCR, ELISA and immunocytochemistry. For studying intracellular signalling pathways, MAP kinase MEK 1/2 was blocked. Cell viability was analysed by an XTT assay and with an EVE automated cell counter. Cell migration was examined by an in vitro wound healing assay.CAP exposition on osteoblast-like cells caused a significant upregulation of interleukin (IL)-1β, IL-6, IL-8, tumor necrosis factor (TNF)α, cyclooxygenase (COX)2, collagen (COL) 1α, matrix metalloproteinase (MMP)1, Ki67, proliferating-cell-nuclear-antigen (PCNA) and chemokine ligand (CCL)2 mRNA expression at 1 day. Interestingly, after blocking of MAP kinase, CAP-induced upregulation of Ki67 was inhibited by 57%. Moreover, CAP treatment improved significantly osteoblast-like cell viability as compared to untreated cells at 1 day. Beneficial effect of CAP treatment was shown by an in vitro wound healing assay, displaying a significant faster wound closure. Our findings provide evidence that CAP exposure effects gene and protein regulation in human osteoblast-like cells. Furthermore, CAP treatment has a positive impact on wound closure in an in vitro setting and might improve existing concepts of hard tissue regeneration in the future.
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Affiliation(s)
- B Eggers
- Department of Oral Surgery, Center of Dento-Maxillo-Facial Medicine, University of Bonn, Bonn, Germany.
| | - J Marciniak
- Section of Experimental Dento-Maxillo-Facial Medicine, Center of Dento-Maxillo-Facial Medicine, University of Bonn, Bonn, Germany
- Department of Orthodontics, Center of Dento-Maxillo-Facial Medicine, University of Bonn, Bonn, Germany
| | - S Memmert
- Section of Experimental Dento-Maxillo-Facial Medicine, Center of Dento-Maxillo-Facial Medicine, University of Bonn, Bonn, Germany
- Department of Orthodontics, Center of Dento-Maxillo-Facial Medicine, University of Bonn, Bonn, Germany
| | - F J Kramer
- Department of Oral Surgery, Center of Dento-Maxillo-Facial Medicine, University of Bonn, Bonn, Germany
- Department of Craniomaxillofacial Surgery, Center of Dento-Maxillo-Facial Medicine, University of Bonn, Bonn, Germany
| | - J Deschner
- Department of Periodontology and Operative Dentistry, University Medical Center of the Johannes Gutenberg University, Mainz, Germany
| | - M Nokhbehsaim
- Section of Experimental Dento-Maxillo-Facial Medicine, Center of Dento-Maxillo-Facial Medicine, University of Bonn, Bonn, Germany
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22
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Abstract
The skeleton is highly vascularized due to the various roles blood vessels play in the homeostasis of bone and marrow. For example, blood vessels provide nutrients, remove metabolic by-products, deliver systemic hormones, and circulate precursor cells to bone and marrow. In addition to these roles, bone blood vessels participate in a variety of other functions. This article provides an overview of the afferent, exchange and efferent vessels in bone and marrow and presents the morphological layout of these blood vessels regarding blood flow dynamics. In addition, this article discusses how bone blood vessels participate in bone development, maintenance, and repair. Further, mechanical loading-induced bone adaptation is presented regarding interstitial fluid flow and pressure, as regulated by the vascular system. The role of the sympathetic nervous system is discussed in relation to blood vessels and bone. Finally, vascular participation in bone accrual with intermittent parathyroid hormone administration, a medication prescribed to combat age-related bone loss, is described and age- and disease-related impairments in blood vessels are discussed in relation to bone and marrow dysfunction. © 2020 American Physiological Society. Compr Physiol 10:1009-1046, 2020.
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Affiliation(s)
- Rhonda D Prisby
- Bone Vascular and Microcirculation Laboratory, Department of Kinesiology, University of Texas at Arlington, Arlington, Texas, USA
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23
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The osteogenic commitment of CD271+CD56+ bone marrow stromal cells (BMSCs) in osteoarthritic femoral head bone. Sci Rep 2020; 10:11145. [PMID: 32636407 PMCID: PMC7341749 DOI: 10.1038/s41598-020-67998-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Accepted: 06/04/2020] [Indexed: 12/13/2022] Open
Abstract
Osteoarthritis (OA), the most common joint disorder, is characterised by progressive structural changes in both the cartilage and the underlying subchondral bone. In late disease stages, subchondral bone sclerosis has been linked to heightened osteogenic commitment of bone marrow stromal cells (BMSCs). This study utilised cell sorting and immunohistochemistry to identify a phenotypically-distinct, osteogenically-committed BMSC subset in human OA trabecular bone. Femoral head trabecular bone tissue digests were sorted into CD45-CD271+CD56+CD146-, CD45-CD271+CD56-CD146+ and CD45-CD271+CD56-CD146-(termed double-negative, DN) subsets, and CD45+CD271-hematopoietic-lineage cells served as control. Compared to the CD146+ subset, the CD56+ subset possessed a lower-level expression of adipocyte-associated genes and significantly over 100-fold higher-level expression of many osteoblast-related genes including osteopontin and osteocalcin, whilst the DN subset presented a transcriptionally ‘intermediate’ BMSC population. All subsets were tri-potential following culture-expansion and were present in control non-OA trabecular bone. However, while in non-OA bone CD56+ cells only localised on the bone surface, in OA bone they were additionally present in the areas of new bone formation rich in osteoblasts and newly-embedded osteocytes. In summary, this study reveals a distinct osteogenically-committed CD271+CD56+ BMSC subset and implicates it in subchondral bone sclerosis in hip OA. CD271+CD56+ subset may represent a future therapeutic target for OA and other bone-associated pathologies.
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Søe K, Delaisse JM, Borggaard XG. Osteoclast formation at the bone marrow/bone surface interface: Importance of structural elements, matrix, and intercellular communication. Semin Cell Dev Biol 2020; 112:8-15. [PMID: 32563679 DOI: 10.1016/j.semcdb.2020.05.016] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Revised: 05/17/2020] [Accepted: 05/19/2020] [Indexed: 12/28/2022]
Abstract
Osteoclasts, the multinucleated cells responsible for bone resorption, have an enormous destructive power which demands to be kept under tight control. Accordingly, the identification of molecular signals directing osteoclastogenesis and switching on their resorptive activity have received much attention. Mandatory factors were identified, but a very essential aspect of the control mechanism of osteoclastic resorption, i.e. its spatial control, remains poorly understood. Under physiological conditions, multinucleated osteoclasts are only detected on the bone surface, while their mono-nucleated precursors are only in the bone marrow. How are pre-osteoclasts targeted to the bone surface? How is their progressive differentiation coordinated with their approach to the bone surface sites to be resorbed, which is where they finally fuse? Here we review the information on the bone marrow distribution of differentiating pre-osteoclasts relative to the position of the mandatory factors for their differentiation as well as relative to physical entities that may affect their access to the remodelling sites. This info allows recognizing an "osteoclastogenesis route" through the bone marrow and leading to the coincident fusion/resorption site - but also points to what still remains to be clarified regarding this route and regarding the restriction of fusion at the resorption site. Finally, we discuss the mechanism responsible for the start of resorption and its spatial extension. This review underscores that fully understanding the control of bone resorption requires to consider it in both space and time - which demands taking into account the context of bone tissue.
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Affiliation(s)
- Kent Søe
- Clinical Cell Biology, Department of Pathology, Odense University Hospital, 5000 Odense C, Denmark; Department of Clinical Research, University of Southern Denmark, 5230 Odense M, Denmark; Department of Molecular Medicine, University of Southern Denmark, 5230 Odense M, Denmark.
| | - Jean-Marie Delaisse
- Clinical Cell Biology, Department of Pathology, Odense University Hospital, 5000 Odense C, Denmark; Department of Clinical Research, University of Southern Denmark, 5230 Odense M, Denmark; Department of Molecular Medicine, University of Southern Denmark, 5230 Odense M, Denmark.
| | - Xenia Goldberg Borggaard
- Clinical Cell Biology, Department of Pathology, Odense University Hospital, 5000 Odense C, Denmark; Department of Clinical Research, University of Southern Denmark, 5230 Odense M, Denmark; Department of Molecular Medicine, University of Southern Denmark, 5230 Odense M, Denmark.
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25
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TRPV1 Contributes to the Neuroprotective Effect of Dexmedetomidine in Pilocarpine-Induced Status Epilepticus Juvenile Rats. BIOMED RESEARCH INTERNATIONAL 2020; 2020:7623635. [PMID: 32337274 PMCID: PMC7168755 DOI: 10.1155/2020/7623635] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Revised: 02/08/2020] [Accepted: 02/20/2020] [Indexed: 11/25/2022]
Abstract
To investigate the antiepileptic and neuroprotective effects of dexmedetomidine (Dex) in pilocarpine- (Pilo-) induced status epilepticus (SE) juvenile rats, rats were randomly assigned to the following six groups (n = 20): normal, normal+Dex, SE, SE+Cap, SE+Dex, and SE+Dex+Cap. The rats were treated with either diazepam (i.p., an antiepileptic drug) or Dex after the onset of SE. The Morris water maze was used to assess rat cognitive behavior. Flow cytometry was used to detect the concentrations of Ca2+, mitochondrial membrane potential, and reactive oxygen species. Transmission electron microscopy was performed to evaluate specimens of brain tissue. The levels of caspase 3 and TRPV1 were examined by western blot and immunohistochemistry (IHC). Treatment with Dex significantly decreased the escape latency of the SE rats (P < 0.05). Capsaicin, a TRPV1 agonist, delivery aggravated the performance of SE rats. Pathological changes in SE rat were attenuated by Dex and deteriorated by capsaicin. Swollen mitochondria and abnormal endoplasmic reticulum were found in SE rats and were then aggravated by capsaicin and reversed by Dex. Moreover, our data showed that Dex significantly restrained calcium overload, ROS production, and mitochondrial membrane potential loss, all of which were induced by Pilo and capsaicin (P < 0.05). Dex decreased the apoptotic rate in the Model SE group (P < 0.05) and TRPV1 and caspase 3 expression in the Dex treatment group (P < 0.05). Interestingly, all these effects of Dex were partially counteracted by the TRPV1 agonist, capsaicin (P < 0.05). Our study showed that Dex exerted a neuroprotective effect in Pilo-induced SE rats by inhibiting TRPV1 expression and provided information for therapy to SE patients.
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26
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Zhang Q, Nettleship I, Schmelzer E, Gerlach J, Zhang X, Wang J, Liu C. Tissue Engineering and Regenerative Medicine Therapies for Cell Senescence in Bone and Cartilage. TISSUE ENGINEERING PART B-REVIEWS 2020; 26:64-78. [DOI: 10.1089/ten.teb.2019.0215] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Qinghao Zhang
- Department of Materials Science and Engineering, East China University of Science and Technology, Shanghai, P.R. China
- Department of Mechanical Engineering and Materials Science, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Ian Nettleship
- Department of Mechanical Engineering and Materials Science, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Eva Schmelzer
- Department of Surgery, McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Jorg Gerlach
- Department of Surgery, McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Xuewei Zhang
- Department of Materials Science and Engineering, East China University of Science and Technology, Shanghai, P.R. China
| | - Jing Wang
- Department of Materials Science and Engineering, East China University of Science and Technology, Shanghai, P.R. China
| | - Changsheng Liu
- Department of Materials Science and Engineering, East China University of Science and Technology, Shanghai, P.R. China
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Andreasen CM, Bakalova LP, Brüel A, Hauge EM, Kiil BJ, Delaisse JM, Kersh ME, Thomsen JS, Andersen TL. The generation of enlarged eroded pores upon existing intracortical canals is a major contributor to endocortical trabecularization. Bone 2020; 130:115127. [PMID: 31689525 DOI: 10.1016/j.bone.2019.115127] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Revised: 10/28/2019] [Accepted: 10/29/2019] [Indexed: 02/04/2023]
Abstract
The gradual conversion of cortical bone into trabecular bone on the endocortical surface contributes substantially to thinning of the cortical bone. The purpose of the present study was to characterize the intracortical canals (3D) and pores (2D) in human fibular bone, to identify the intracortical remodeling events leading to this endocortical trabecularization. The analysis was conducted in fibular diaphyseal bone specimens obtained from 20 patients (6 women and 14 men, age range 41-75 years). μCT revealed that endosteal bone had a higher cortical porosity (p< 0.05) and canals with a larger diameter (p< 0.05) than periosteal bone, while the canal spacing and number were similar in the endosteal and periosteal half. Histological analysis showed that the endosteal half versus the periosteal half: (i) had a higher likelihood of being non-quiescent type 2 pores (i.e. remodeling of existing pores) than other pore types (OR = 1.6, p< 0.01); (ii) that the non-quiescent type 2 pores contributed to a higher porosity (p< 0.001); and that (iii) amongst these pores especially eroded type 2 pores contributed to the elevated cortical porosity (p< 0.001). In conclusion, we propose that endocortical trabecularization results from the accumulation of eroded cavities upon existing intracortical canals, favored by delayed initiation of bone formation.
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Affiliation(s)
- Christina Møller Andreasen
- Department of Orthopedic Surgery & Traumatology, Odense University Hospital, Odense, Denmark; Clinical Cell Biology, Research Unit of Pathology, Department of Clinical Research, University of Southern Denmark and Department of Pathology, Odense University Hospital, Odense, Denmark; Department of Molecular Medicine, University of Southern Denmark, Odense, Denmark.
| | - Lydia Peteva Bakalova
- Department of Mechanical Science and Engineering, University of Illinois at Urbana-Champaign, IL, USA.
| | - Annemarie Brüel
- Department of Biomedicine, Aarhus University, Aarhus, Denmark.
| | - Ellen Margrethe Hauge
- Department of Rheumatology, Aarhus University Hospital and Department of Clinical Medicine, Aarhus University, Aarhus, Denmark.
| | - Birgitte Jul Kiil
- Department of Plastic Surgery, Aarhus University Hospital, Aarhus, Denmark.
| | - Jean-Marie Delaisse
- Clinical Cell Biology, Research Unit of Pathology, Department of Clinical Research, University of Southern Denmark and Department of Pathology, Odense University Hospital, Odense, Denmark; Department of Molecular Medicine, University of Southern Denmark, Odense, Denmark; Clinical Cell Biology, Vejle Hospital - Lillebælt Hospital, University of Southern Denmark, Vejle, Denmark.
| | - Mariana Elizabeth Kersh
- Department of Mechanical Science and Engineering, University of Illinois at Urbana-Champaign, IL, USA.
| | | | - Thomas Levin Andersen
- Clinical Cell Biology, Research Unit of Pathology, Department of Clinical Research, University of Southern Denmark and Department of Pathology, Odense University Hospital, Odense, Denmark; Department of Molecular Medicine, University of Southern Denmark, Odense, Denmark; Clinical Cell Biology, Vejle Hospital - Lillebælt Hospital, University of Southern Denmark, Vejle, Denmark; Department of Forensic Medicine, Aarhus University, Aarhus, Denmark.
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28
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Søe K, Andersen TL, Hinge M, Rolighed L, Marcussen N, Delaisse JM. Coordination of Fusion and Trafficking of Pre-osteoclasts at the Marrow-Bone Interface. Calcif Tissue Int 2019; 105:430-445. [PMID: 31236622 DOI: 10.1007/s00223-019-00575-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Accepted: 06/14/2019] [Indexed: 12/16/2022]
Abstract
Fusion is the final osteoclast differentiation step leading to bone resorption. In healthy trabecular bone, osteoclast fusion is restricted to bone surfaces undergoing resorption, and necessarily requires site-specific recruitment of mononucleated pre-osteoclasts originating from the bone marrow. However, the spatiotemporal mechanism coordinating recruitment and fusion is poorly investigated. Herein we identify a collagen/vascular network as a likely structure supporting this mechanism. We therefore used multiplex immunohistochemistry and electron microscopy on human iliac crest bone samples, in combination with functional assays performed in vitro with osteoclasts generated from healthy blood donors. First, we found that putative pre-osteoclasts are in close vicinity of a network of collagen fibers associated with vessels and bone remodeling compartment canopies. Based on 3D-reconstructions of serial sections, we propose that this network may serve as roads leading pre-osteoclasts to resorption sites, as reported for cell migration in other tissues. Importantly, almost all these bone marrow pre-osteoclasts, but only some osteoclasts, express the collagen receptor OSCAR, which is reported to induce fusion competence. Furthermore, differentiating osteoclasts cultured on collagen compared to mineral show higher fusion rates, higher expression of fusogenic cytokines, and a CD47 plasma membrane distribution pattern reported to be typical of a pre-fusion state-thus collectively supporting collagen-induced fusion competence. Finally, these in vitro assays show that collagen induces high cell mobility. The present data lead to a model where collagen fibers/vasculature support the coordination between traffic and fusion of pre-osteoclasts, by serving as a physical road and inducing fusion competence as well as cell mobility.
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Affiliation(s)
- Kent Søe
- Clinical Cell Biology, Department of Regional Health Research, Vejle Hospital - Lillebaelt Hospital, University of Southern Denmark, Beriderbakken 4, 7100, Vejle, Denmark.
- Clinical Cell Biology, Department of Pathology, Odense University Hospital - Department of Clinical Research, University of Southern Denmark, J. B. Winsløvs Vej 25, 1st floor, 5000, Odense C, Denmark.
| | - Thomas Levin Andersen
- Clinical Cell Biology, Department of Regional Health Research, Vejle Hospital - Lillebaelt Hospital, University of Southern Denmark, Beriderbakken 4, 7100, Vejle, Denmark.
- Clinical Cell Biology, Department of Pathology, Odense University Hospital - Department of Clinical Research, University of Southern Denmark, J. B. Winsløvs Vej 25, 1st floor, 5000, Odense C, Denmark.
| | - Maja Hinge
- Clinical Cell Biology, Department of Regional Health Research, Vejle Hospital - Lillebaelt Hospital, University of Southern Denmark, Beriderbakken 4, 7100, Vejle, Denmark
- Department of Internal Medicine, Section of Hematology, Vejle Hospital - Lillebaelt Hospital, Beriderbakken 4, 7100, Vejle, Denmark
| | - Lars Rolighed
- Breast and Endocrine Section, Department of Surgery, Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, 8200, Aarhus N, Denmark
| | - Niels Marcussen
- Department of Pathology, Odense University Hospital, J. B. Winsløws Vej 15, 5000, Odense, Denmark
| | - Jean-Marie Delaisse
- Clinical Cell Biology, Department of Regional Health Research, Vejle Hospital - Lillebaelt Hospital, University of Southern Denmark, Beriderbakken 4, 7100, Vejle, Denmark
- Clinical Cell Biology, Department of Pathology, Odense University Hospital - Department of Clinical Research, University of Southern Denmark, J. B. Winsløvs Vej 25, 1st floor, 5000, Odense C, Denmark
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29
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Sims NA, Martin TJ. Osteoclasts Provide Coupling Signals to Osteoblast Lineage Cells Through Multiple Mechanisms. Annu Rev Physiol 2019; 82:507-529. [PMID: 31553686 DOI: 10.1146/annurev-physiol-021119-034425] [Citation(s) in RCA: 140] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Bone remodeling is essential for the repair and replacement of damaged and old bone. The major principle underlying this process is that osteoclast-mediated resorption of a quantum of bone is followed by osteoblast precursor recruitment; these cells differentiate to matrix-producing osteoblasts, which form new bone to replace what was resorbed. Evidence from osteopetrotic syndromes indicate that osteoclasts not only resorb bone, but also provide signals to promote bone formation. Osteoclasts act upon osteoblast lineage cells throughout their differentiation by facilitating growth factor release from resorbed matrix, producing secreted proteins and microvesicles, and expressing membrane-bound factors. These multiple mechanisms mediate the coupling of bone formation to resorption in remodeling. Additional interactions of osteoclasts with osteoblast lineage cells, including interactions with canopy and reversal cells, are required to achieve coordination between bone formation and resorption during bone remodeling.
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Affiliation(s)
- Natalie A Sims
- Bone Cell 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 Cell 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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30
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Sayilekshmy M, Hansen RB, Delaissé JM, Rolighed L, Andersen TL, Heegaard AM. Innervation is higher above Bone Remodeling Surfaces and in Cortical Pores in Human Bone: Lessons from patients with primary hyperparathyroidism. Sci Rep 2019; 9:5361. [PMID: 30926835 PMCID: PMC6441095 DOI: 10.1038/s41598-019-41779-w] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Accepted: 03/13/2019] [Indexed: 01/07/2023] Open
Abstract
Mounting evidence from animal studies suggests a role of the nervous system in bone physiology. However, little is known about the nerve fiber localization to human bone compartments and bone surface events. This study reveals the density and distribution of nerves in human bone and the association of nerve profiles to bone remodeling events and vascular structures in iliac crest biopsies isolated from patients diagnosed with primary hyperparathyroidism (PHPT). Bone sections were sequentially double-immunostained for tyrosine hydroxylase (TH), a marker for sympathetic nerves, followed by protein gene product 9.5 (PGP9.5), a pan-neuronal marker, or double-immunostained for either PGP9.5 or TH in combination with CD34, an endothelial marker. In the bone marrow, the nerve profile density was significantly higher above remodeling surfaces as compared to quiescent bone surfaces. Ninety-five percentages of all nerve profiles were associated with vascular structures with the highest association to capillaries and arterioles. Moreover, vasculature with innervation was denser above bone remodeling surfaces. Finally, the nerve profiles density was 5-fold higher in the intracortical pores compared to bone marrow and periosteum. In conclusion, the study shows an anatomical link between innervation and bone remodeling in human bone.
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Affiliation(s)
- Manasi Sayilekshmy
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark
| | - Rie Bager Hansen
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark
| | - Jean-Marie Delaissé
- Department of Clinical Cell Biology, Vejle Hospital - Lillebaelt Hospital, Institute of Regional Health Research, University of Southern Denmark, Vejle, Denmark.,Clinical Cell Biology, Research Unit of Pathology, Department of Clinical Research, University of Southern Denmark, Odense University Hospital, Odense, Denmark.,Department of Forensic Medicine, Aarhus University, Aarhus, Denmark
| | - Lars Rolighed
- Department of Surgery and Department of Otorhinolaryngology, Aarhus University Hospital, Aarhus, Denmark
| | - Thomas Levin Andersen
- Department of Clinical Cell Biology, Vejle Hospital - Lillebaelt Hospital, Institute of Regional Health Research, University of Southern Denmark, Vejle, Denmark. .,Clinical Cell Biology, Research Unit of Pathology, Department of Clinical Research, University of Southern Denmark, Odense University Hospital, Odense, Denmark. .,Department of Forensic Medicine, Aarhus University, Aarhus, Denmark.
| | - Anne-Marie Heegaard
- Department of Drug Design and Pharmacology, University of Copenhagen, Copenhagen, Denmark.
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31
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KIAA1199 is a secreted molecule that enhances osteoblastic stem cell migration and recruitment. Cell Death Dis 2019; 10:126. [PMID: 30755597 PMCID: PMC6372631 DOI: 10.1038/s41419-018-1202-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Revised: 10/22/2018] [Accepted: 10/31/2018] [Indexed: 12/13/2022]
Abstract
Factors mediating mobilization of osteoblastic stem and progenitor cells from their bone marrow niche to be recruited to bone formation sites during bone remodeling are poorly known. We have studied secreted factors present in the bone marrow microenvironment and identified KIAA1199 (also known as CEMIP, cell migration inducing hyaluronan binding protein) in human bone biopsies as highly expressed in osteoprogenitor reversal cells (Rv.C) recruited to the eroded surfaces (ES), which are the future bone formation sites. In vitro, KIAA1199 did not affect the proliferation of human osteoblastic stem cells (also known as human bone marrow skeletal or stromal stem cells, hMSCs); but it enhanced cell migration as determined by scratch assay and trans-well migration assay. KIAA1199 deficient hMSCs (KIAA1199down) exhibited significant changes in cell size, cell length, ratio of cell width to length and cell roundness, together with reduction of polymerization actin (F-actin) and changes in phos-CFL1 (cofflin1), phos-LIMK1 (LIM domain kinase 1) and DSTN (destrin), key factors regulating actin cytoskeletal dynamics and cell motility. Moreover, KIAA1199down hMSC exhibited impaired Wnt signaling in TCF-reporter assay and decreased expression of Wnt target genes and these effects were rescued by KIAA1199 treatment. Finally, KIAA1199 regulated the activation of P38 kinase and its associated changes in Wnt-signaling. Thus, KIAA1199 is a mobilizing factor that interacts with P38 and Wnt signaling, and induces changes in actin cytoskeleton, as a mechanism mediating recruitment of hMSC to bone formation sites.
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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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33
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Fornetti J, Welm AL, Stewart SA. Understanding the Bone in Cancer Metastasis. J Bone Miner Res 2018; 33:2099-2113. [PMID: 30476357 DOI: 10.1002/jbmr.3618] [Citation(s) in RCA: 248] [Impact Index Per Article: 41.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Revised: 10/17/2018] [Accepted: 10/18/2018] [Indexed: 12/11/2022]
Abstract
The bone is the third most common site of metastasis for a wide range of solid tumors including lung, breast, prostate, colorectal, thyroid, gynecologic, and melanoma, with 70% of metastatic prostate and breast cancer patients harboring bone metastasis.1 Unfortunately, once cancer spreads to the bone, it is rarely cured and is associated with a wide range of morbidities including pain, increased risk of fracture, and hypercalcemia. This fact has driven experts in the fields of bone and cancer biology to study the bone, and has revealed that there is a great deal that each can teach the other. The complexity of the bone was first described in 1889 when Stephen Paget proposed that tumor cells have a proclivity for certain organs, where they "seed" into a friendly "soil" and eventually grow into metastatic lesions. Dr. Paget went on to argue that although many study the "seed" it would be paramount to understand the "soil." Since this original work, significant advances have been made not only in understanding the cell-autonomous mechanisms that drive metastasis, but also alterations which drive changes to the "soil" that allow a tumor cell to thrive. Indeed, it is now clear that the "soil" in different metastatic sites is unique, and thus the mechanisms that allow tumor cells to remain in a dormant or growing state are specific to the organ in question. In the bone, our knowledge of the components that contribute to this fertile "soil" continues to expand, but our understanding of how they impact tumor growth in the bone remains in its infancy. Indeed, we now appreciate that the endosteal niche likely contributes to tumor cell dormancy, and that osteoclasts, osteocytes, and adipocytes can impact tumor cell growth. Here, we discuss the bone microenvironment and how it impacts cancer cell seeding, dormancy, and growth. © 2018 American Society for Bone and Mineral Research.
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Affiliation(s)
- Jaime Fornetti
- Department of Oncological Sciences, Huntsman Cancer Institute, University of Utah, Salt Lake City, UT, USA
| | - Alana L Welm
- Department of Oncological Sciences, Huntsman Cancer Institute, University of Utah, Salt Lake City, UT, USA
| | - Sheila A Stewart
- Departments of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO, USA.,Siteman Cancer Center, Washington University School of Medicine, St. Louis, MO, USA.,Integrating Communication within the Cancer Environment (ICCE) Institute, Washington University School of Medicine, St. Louis, MO, USA
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34
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Sun BY, Zhao BX, Zhu JY, Sun ZP, Shi YA, Huang F. Role of TGF‑β1 expressed in bone marrow‑derived mesenchymal stem cells in promoting bone formation in a rabbit femoral defect model. Int J Mol Med 2018; 42:897-904. [PMID: 29786743 PMCID: PMC6034935 DOI: 10.3892/ijmm.2018.3692] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Accepted: 05/10/2018] [Indexed: 01/09/2023] Open
Abstract
Bone defects represent a major clinical and socioeconomic problem without suitable treatment options. Previous studies have shown that transforming growth factor β1 (TGF‑β1) is important in the development of various diseases. The present study aimed to investigate the therapeutic potential of rabbit bone marrow‑derived mesenchymal stem cells (BMSCs) expressing TGF‑β1 in the treatment of rabbit femoral defects. First, rabbit BMSCs were identified and cultured. TGF‑β1 was then stably overexpressed in the rabbit BMSCs by lentivirus transfection, which was expressed at a high level in the femoral defects treated with TGF‑β1‑overexpressing BMSCs, compared with PBS‑treated controls. In addition, the TGF‑β1‑overexpressing BMSCs promoted new bone formation in the rabbit femoral defect model, and increased the expression of bone‑related markers at week 2 and week 6. Therefore, the study demonstrated that BMSCs overexpressing TGF‑β1 may provide a novel therapeutic option for femoral defects.
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Affiliation(s)
- Bing-Yin Sun
- Department of Orthopedics, Shunde Hospital of Guangzhou University of Chinese Medicine, Foshan, Guangdong 528200, P.R. China
| | - Bao-Xiang Zhao
- Department of Orthopedics, Linyi People's Hospital, Linyi, Shandong 276000, P.R. China
| | - Jie-Ying Zhu
- Department of Substance Dependence, The Affiliated Brain Hospital of Guangzhou Medical University (Guangzhou Huiai Hospital), Guangzhou, Guangdong 510370, P.R. China
| | - Zheng-Ping Sun
- Physical Examination Center, The Second Traditional Chinese Medicine Hospital of Guangdong Provence, Guangzhou, Guangdong 510095, P.R. China
| | - Yong-An Shi
- Department of Microsurgery II, Wendeng Hospital of Traditional Chinese of Orthopedics and Traumatology of Shandong, Wendeng, Shandong 264400, P.R. China
| | - Feng Huang
- Department of Orthopedics, The First Affiliated Hospital of Guangzhou University of Traditional Chinese Medicine, Guangzhou, Guangdong 510405, P.R. China
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Abstract
Osteoporosis, characterized by low bone mass and micro-architectural deterioration of bone tissue with increased risk of fracture, can be categorized into two forms: primary and secondary, depending on whether it occurs as part of the natural aging process (estrogen deficiency) or as part of disease pathology. In both forms bone loss is due to an imbalance in the bone remodeling process, with resorption/formation skewed more toward bone loss. Recent studies and emerging evidence consistently demonstrate the potential of the intestinal microbiota to modulate bone health. This review discusses the process of bone remodeling and the pathology of osteoporosis and introduces the intestinal microbiota and its potential to influence bone health. In particular, we highlight recent murine studies that examine how probiotic supplementation can both increase bone density in healthy individuals and protect against primary (estrogen deficiency) as well as secondary osteoporosis. Potential mechanisms are described to account for how probiotic treatments could be exerting their beneficial effect on bone health.
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Grosso A, Burger MG, Lunger A, Schaefer DJ, Banfi A, Di Maggio N. It Takes Two to Tango: Coupling of Angiogenesis and Osteogenesis for Bone Regeneration. Front Bioeng Biotechnol 2017; 5:68. [PMID: 29164110 PMCID: PMC5675838 DOI: 10.3389/fbioe.2017.00068] [Citation(s) in RCA: 247] [Impact Index Per Article: 35.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2017] [Accepted: 10/16/2017] [Indexed: 12/29/2022] Open
Abstract
Bone regeneration is a complex process requiring highly orchestrated interactions between different cells and signals to form new mineralized tissue. Blood vessels serve as a structural template, around which bone development takes place, and also bring together the key elements for bone homeostasis into the osteogenic microenvironment, including minerals, growth factors and osteogenic progenitor cells. Vascular endothelial growth factor (VEGF) is the master regulator of vascular growth and it is required for effective coupling of angiogenesis and osteogenesis during both skeletal development and postnatal bone repair. Here, we will review the current state of knowledge on the molecular cross-talk between angiogenesis and osteogenesis. In particular, we will focus on the role of VEGF in coupling these two processes and how VEGF dose can control the outcome, addressing in particular: (1) the direct influence of VEGF on osteogenic differentiation of mesenchymal progenitors; (2) the angiocrine functions of endothelium to regulate osteoprogenitors; (3) the role of immune cells, e.g., myeloid cells and osteoclast precursors, recruited by VEGF to the osteogenic microenvironment. Finally, we will discuss emerging strategies, based on the current biological understanding, to ensure rapid vascularization and efficient bone formation in regenerative medicine.
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Affiliation(s)
- Andrea Grosso
- Department of Biomedicine, University Hospital, University of Basel, Basel, Switzerland
| | - Maximilian G Burger
- Department of Plastic, Reconstructive, Aesthetic and Hand Surgery, University Hospital of Basel, Basel, Switzerland
| | - Alexander Lunger
- Department of Plastic, Reconstructive, Aesthetic and Hand Surgery, University Hospital of Basel, Basel, Switzerland
| | - Dirk J Schaefer
- Department of Plastic, Reconstructive, Aesthetic and Hand Surgery, University Hospital of Basel, Basel, Switzerland
| | - Andrea Banfi
- Department of Biomedicine, University Hospital, University of Basel, Basel, Switzerland
| | - Nunzia Di Maggio
- Department of Biomedicine, University Hospital, University of Basel, Basel, Switzerland
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37
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Affiliation(s)
- T John Martin
- St Vincent's Institute of Medical Research, University of Melbourne Department of Medicine, Fitzroy, Australia
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38
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Drake MT, Clarke BL, Oursler MJ, Khosla S. Cathepsin K Inhibitors for Osteoporosis: Biology, Potential Clinical Utility, and Lessons Learned. Endocr Rev 2017; 38:325-350. [PMID: 28651365 PMCID: PMC5546879 DOI: 10.1210/er.2015-1114] [Citation(s) in RCA: 156] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/07/2015] [Accepted: 06/20/2017] [Indexed: 12/24/2022]
Abstract
Cathepsin K is a cysteine protease member of the cathepsin lysosomal protease family. Although cathepsin K is highly expressed in osteoclasts, lower levels of cathepsin K are also found in a variety of other tissues. Secretion of cathepsin K from the osteoclast into the sealed osteoclast-bone cell interface results in efficient degradation of type I collagen. The absence of cathepsin K activity in humans results in pycnodysostosis, characterized by increased bone mineral density and fractures. Pharmacologic cathepsin K inhibition leads to continuous increases in bone mineral density for ≤5 years of treatment and improves bone strength at the spine and hip. Compared with other antiresorptive agents, cathepsin K inhibition is nearly equally efficacious for reducing biochemical markers of bone resorption but comparatively less active for reducing bone formation markers. Despite multiple efforts to develop cathepsin K inhibitors, potential concerns related to off-target effects of the inhibitors against other cathepsins and cathepsin K inhibition at nonbone sites, including skin and perhaps cardiovascular and cerebrovascular sites, prolonged the regulatory approval process. A large multinational randomized, double-blind phase III study of odanacatib in postmenopausal women with osteoporosis was recently completed. Although that study demonstrated clinically relevant reductions in fractures at multiple sites, odanacatib was ultimately withdrawn from the regulatory approval process after it was found to be associated with an increased risk of cerebrovascular accidents. Nonetheless, the underlying biology and clinical effects of cathepsin K inhibition remain of considerable interest and could guide future therapeutic approaches for osteoporosis.
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Affiliation(s)
- Matthew T. Drake
- Division of Endocrinology and Kogod Center on Aging, Mayo Clinic College of Medicine, Rochester, Minnesota 55905
| | - Bart L. Clarke
- Division of Endocrinology and Kogod Center on Aging, Mayo Clinic College of Medicine, Rochester, Minnesota 55905
| | - Merry Jo Oursler
- Division of Endocrinology and Kogod Center on Aging, Mayo Clinic College of Medicine, Rochester, Minnesota 55905
| | - Sundeep Khosla
- Division of Endocrinology and Kogod Center on Aging, Mayo Clinic College of Medicine, Rochester, Minnesota 55905
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Focal Defects of the Knee Articular Surface: Evidence of a Regenerative Potential Pattern in Osteochondritis Dissecans and Degenerative Lesions. BIOMED RESEARCH INTERNATIONAL 2017; 2017:9036305. [PMID: 28770227 PMCID: PMC5523180 DOI: 10.1155/2017/9036305] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/03/2017] [Accepted: 05/31/2017] [Indexed: 12/20/2022]
Abstract
The surgical treatment of knee articular focal lesions may offer heterogeneous clinical results. Osteochondritis dissecans (OCD) lesions showed to heal better than degenerative lesions (DL) but the underlying biological reasons are unknown. We evaluated the basal histological and immunohistochemical characteristics of these lesions analyzing a series of osteochondral fragments from young patients with similar age but presenting different etiology. Osteochondral tissue samples were stained with Safranin O and graded using a histological score. Markers of mesenchymal progenitor cells (CD146), osteoclasts (tartrate-resistant acid phosphatase, TRAP), and vessels (CD34) were evaluated. Histological score showed a higher degeneration of both cartilage and bone compartments in OCD compared to DL fragments. Only CD146-positive cells were found at the same percentage in cartilage compartment of both DL and OCD patients. By contrast, in the bone compartment a significantly higher percentage of CD146, TRAP, and CD34 markers was found in OCD compared to DL patients. These data showed distinct histological characteristics of osteochondral focal lesions located in the same anatomical region but having a different etiology. The higher percentages of these markers in OCD than in DL, mainly associated with a high bone turnover, could help to explain the higher clinical healing potential of OCD patients.
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40
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Lin B, Huang JF, Liu XW, Ma XT, Liu XL, Lu Y, Zhou Y, Guo FM, Feng TT. Rapid, microwave-accelerated synthesis and anti-osteoporosis activities evaluation of Morusin scaffolds and Morusignin L scaffolds. Bioorg Med Chem Lett 2017; 27:2389-2396. [DOI: 10.1016/j.bmcl.2017.04.018] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2017] [Revised: 04/03/2017] [Accepted: 04/05/2017] [Indexed: 11/17/2022]
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Endocultivation: continuous application of rhBMP-2 via mini-osmotic pumps to induce bone formation at extraskeletal sites. Int J Oral Maxillofac Surg 2017; 46:655-661. [DOI: 10.1016/j.ijom.2017.01.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2016] [Revised: 11/10/2016] [Accepted: 01/18/2017] [Indexed: 11/23/2022]
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42
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Gruber R, Stadlinger B, Terheyden H. Cell-to-cell communication in guided bone regeneration: molecular and cellular mechanisms. Clin Oral Implants Res 2016; 28:1139-1146. [PMID: 27550738 DOI: 10.1111/clr.12929] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/16/2016] [Indexed: 12/19/2022]
Abstract
This overview provides insights into the molecular and cellular mechanisms involved in guided bone regeneration, in particular focusing on aspects presented in the 3D movie, Cell-To-Cell Communication in Guided Bone Regeneration. The information presented here is based almost exclusively on genetic mouse models in which single genes can be deleted or overexpressed, even in a specific cell type. This information needs to be extrapolated to humans and related to aspects relevant to graft consolidation under the clinical parameters of guided bone regeneration. The overview follows the ground tenor of the Cell-To-Cell Communication series and focuses on aspects of cell-to-cell communication in bone regeneration and guided bone regeneration. Here, we discuss (1) the role of inflammation during bone regeneration, including (2) the importance of the fibrin matrix, and (3) the pleiotropic functions of macrophages. We highlight (4) the origin of bone-forming osteoblasts and bone-resorbing osteoclasts as well as (5) what causes a progenitor cell to mature into an effector cell. (6) We touch on the complex bone adaptation and maintenance after graft consolidation and (7) how osteocytes control this process. Finally, we speculate on (8) how barrier membranes and the augmentation material can modulate graft consolidation.
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Affiliation(s)
- Reinhard Gruber
- Department of Oral Biology, Medical University of Vienna, Vienna, Austria.,Department of Preventive, Restorative and Pediatric Dentistry, School of Dental Medicine, University of Bern, Bern, Switzerland
| | - Bernd Stadlinger
- Clinic of Cranio-Maxillofacial and Oral Surgery, University of Zurich, Zurich, Switzerland
| | - Hendrik Terheyden
- Department of Oral & Maxillofacial Surgery, Red Cross Hospital, Kassel, Germany
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43
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Abstract
During the past decade preclinical studies have defined many of the mechanisms used by tumours to hijack the skeleton and promote bone metastasis. This has led to the development and widespread clinical use of bone-targeted drugs to prevent skeletal-related events. This understanding has also identified a critical dependency between colonizing tumour cells and the cells of bone. This is particularly important when tumour cells first arrive in bone, adapt to their new microenvironment and enter a long-lived dormant state. In this Review, we discuss the role of different bone cell types in supporting disseminated tumour cell dormancy and reactivation, and highlight the new opportunities this provides for targeting the bone microenvironment to control dormancy and bone metastasis.
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Affiliation(s)
- Peter I Croucher
- Division of Bone Biology, Garvan Institute of Medical Research, 384 Victoria Street, Sydney, New South Wales 2010, Australia
- St Vincent's Clinical School, University of New South Wales Medicine, Sydney, New South Wales 2052, Australia
- School of Biotechnology and Biomolecular Sciences, University of New South Wales Australia, Sydney, New South Wales 2052, Australia
| | - Michelle M McDonald
- Division of Bone Biology, Garvan Institute of Medical Research, 384 Victoria Street, Sydney, New South Wales 2010, Australia
- St Vincent's Clinical School, University of New South Wales Medicine, Sydney, New South Wales 2052, Australia
| | - T John Martin
- St Vincent's Institute of Medical Research, 9 Princes Street, Fitzroy, Melbourne, Victoria 3065, Australia
- Department of Medicine, University of Melbourne, St Vincent's Hospital, Melbourne, Victoria 3065, Australia
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Bonomo A, Monteiro AC, Gonçalves-Silva T, Cordeiro-Spinetti E, Galvani RG, Balduino A. A T Cell View of the Bone Marrow. Front Immunol 2016; 7:184. [PMID: 27242791 PMCID: PMC4868947 DOI: 10.3389/fimmu.2016.00184] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2015] [Accepted: 04/29/2016] [Indexed: 01/20/2023] Open
Abstract
The majority of T cells present in the bone marrow (BM) represent an activated/memory phenotype and most of these, if not all, are circulating T cells. Their lodging in the BM keeps them activated, turning the BM microenvironment into a “memory reservoir.” This article will focus on how T cell activation in the BM results in both direct and indirect effects on the hematopoiesis. The hematopoietic stem cell niche will be presented, with its main components and organization, along with the role played by T lymphocytes in basal and pathologic conditions and their effect on the bone remodeling process. Also discussed herein will be how “normal” bone mass peak is achieved only in the presence of an intact adaptive immune system, with T and B cells playing critical roles in this process. Our main hypothesis is that the partnership between T cells and cells of the BM microenvironment orchestrates numerous processes regulating immunity, hematopoiesis, and bone remodeling.
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Affiliation(s)
- Adriana Bonomo
- Cancer Program (Fio-Cancer), Oswaldo Cruz Foundation, Rio de Janeiro, Brazil; Laboratory on Thymus Research, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
| | - Ana Carolina Monteiro
- Laboratory on Thymus Research, Oswaldo Cruz Institute, Oswaldo Cruz Foundation , Rio de Janeiro , Brazil
| | - Triciana Gonçalves-Silva
- Laboratory on Thymus Research, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil; Immunology and Inflammation Graduate Program, Paulo de Góes Microbiology Institute, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Eric Cordeiro-Spinetti
- Cell Biology and Technology Laboratory, Veiga de Almeida University , Rio de Janeiro , Brazil
| | - Rômulo Gonçalves Galvani
- Cancer Program (Fio-Cancer), Oswaldo Cruz Foundation, Rio de Janeiro, Brazil; Laboratory on Thymus Research, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Rio de Janeiro, Brazil; Microbiology Graduate Program, Paulo de Góes Microbiology Institute, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Alex Balduino
- Cell Biology and Technology Laboratory, Veiga de Almeida University, Rio de Janeiro, Brazil; Excellion Laboratory, Amil/UnitedHealth Group, Petrópolis, Brazil
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45
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Böhm AM, Dirckx N, Maes C. Recruitment of osteogenic cells to bone formation sites during development and fracture repair. Z Rheumatol 2016; 76:5-9. [PMID: 27001056 DOI: 10.1007/s00393-015-1574-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Recruitment of osteoblast lineage cells to their bone-forming locations is essential for skeletal development and fracture healing. In developing bones, osteoprogenitor cells invade the cartilage mold to establish the primary ossification center. Similarly, osteogenic cells infiltrate and populate the callus tissue that is formed following an injury. Proper bone development and successful fracture repair must, therefore, rely on controlled temporal and spatial navigation cues guiding the cells to the sites where new bone formation is needed. Some cellular mechanisms and molecular pathways involved have been elucidated.
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Affiliation(s)
- A-M Böhm
- Laboratory of Skeletal Cell Biology and Physiology (SCEBP), Skeletal Biology and Engineering Research Center (SBE), Department of Development and Regeneration, Gasthuisberg O&N 1, KU Leuven, Herestraat 49, box 813, B-3000, Leuven, Belgium
| | - N Dirckx
- Laboratory of Skeletal Cell Biology and Physiology (SCEBP), Skeletal Biology and Engineering Research Center (SBE), Department of Development and Regeneration, Gasthuisberg O&N 1, KU Leuven, Herestraat 49, box 813, B-3000, Leuven, Belgium
| | - C Maes
- Laboratory of Skeletal Cell Biology and Physiology (SCEBP), Skeletal Biology and Engineering Research Center (SBE), Department of Development and Regeneration, Gasthuisberg O&N 1, KU Leuven, Herestraat 49, box 813, B-3000, Leuven, Belgium.
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46
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Böhm AM, Dirckx N, Maes C. [Recruitment of osteogenic cells to bone formation sites during development and fracture repair - German Version]. Z Rheumatol 2016; 75:316-21. [PMID: 27003859 DOI: 10.1007/s00393-016-0065-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Recruitment of osteoblast lineage cells to their bone-forming locations is essential for skeletal development and fracture healing. In developing bones, osteoprogenitor cells invade the cartilage mold to establish the primary ossification center. Similarly, osteogenic cells infiltrate and populate the callus tissue that is formed following an injury. Proper bone development and successful fracture repair must, therefore, rely on controlled temporal and spatial navigation cues guiding the cells to the sites where new bone formation is needed. Some cellular mechanisms and molecular pathways involved have been elucidated.
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Affiliation(s)
- A-M Böhm
- Laboratory of Skeletal Cell Biology and Physiology (SCEBP), Skeletal Biology and Engineering Research Center (SBE), Department of Development and Regeneration, KU Leuven, Gasthuisberg O&N 1, Herestraat 49, Box 813, 3000, Leuven, Belgien
| | - N Dirckx
- Laboratory of Skeletal Cell Biology and Physiology (SCEBP), Skeletal Biology and Engineering Research Center (SBE), Department of Development and Regeneration, KU Leuven, Gasthuisberg O&N 1, Herestraat 49, Box 813, 3000, Leuven, Belgien
| | - C Maes
- Laboratory of Skeletal Cell Biology and Physiology (SCEBP), Skeletal Biology and Engineering Research Center (SBE), Department of Development and Regeneration, KU Leuven, Gasthuisberg O&N 1, Herestraat 49, Box 813, 3000, Leuven, Belgien.
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47
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Abdelgawad ME, Delaisse JM, Hinge M, Jensen PR, Alnaimi RW, Rolighed L, Engelholm LH, Marcussen N, Andersen TL. Early reversal cells in adult human bone remodeling: osteoblastic nature, catabolic functions and interactions with osteoclasts. Histochem Cell Biol 2016; 145:603-15. [PMID: 26860863 DOI: 10.1007/s00418-016-1414-y] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/15/2015] [Indexed: 12/31/2022]
Abstract
The mechanism coupling bone resorption and formation is a burning question that remains incompletely answered through the current investigations on osteoclasts and osteoblasts. An attractive hypothesis is that the reversal cells are likely mediators of this coupling. Their nature is a big matter of debate. The present study performed on human cancellous bone is the first one combining in situ hybridization and immunohistochemistry to demonstrate their osteoblastic nature. It shows that the Runx2 and CD56 immunoreactive reversal cells appear to take up TRAcP released by neighboring osteoclasts. Earlier preclinical studies indicate that reversal cells degrade the organic matrix left behind by the osteoclasts and that this degradation is crucial for the initiation of the subsequent bone formation. To our knowledge, this study is the first addressing these catabolic activities in adult human bone through electron microscopy and analysis of molecular markers. Periosteoclastic reversal cells show direct contacts with the osteoclasts and with the demineralized resorption debris. These early reversal cells show (1) ¾-collagen fragments typically generated by extracellular collagenases of the MMP family, (2) MMP-13 (collagenase-3) and (3) the endocytic collagen receptor uPARAP/Endo180. The prevalence of these markers was lower in the later reversal cells, which are located near the osteoid surfaces and morphologically resemble mature bone-forming osteoblasts. In conclusion, this study demonstrates that reversal cells colonizing bone surfaces right after resorption are osteoblast-lineage cells, and extends to adult human bone remodeling their role in rendering eroded surfaces osteogenic.
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Affiliation(s)
- Mohamed Essameldin Abdelgawad
- Department of Clinical Cell Biology (KCB), Vejle Hospital - Lillebaelt Hospital, IRS, University of Southern Denmark, Kabbeltoft 25, 7100, Vejle, Denmark.,Faculty of Science, Helwan University, Helwan, Egypt
| | - Jean-Marie Delaisse
- Department of Clinical Cell Biology (KCB), Vejle Hospital - Lillebaelt Hospital, IRS, University of Southern Denmark, Kabbeltoft 25, 7100, Vejle, Denmark.
| | - Maja Hinge
- Department of Clinical Cell Biology (KCB), Vejle Hospital - Lillebaelt Hospital, IRS, University of Southern Denmark, Kabbeltoft 25, 7100, Vejle, Denmark.,Division of Hematology, Department of Internal Medicine, Vejle Hospital - Lillebaelt Hospital, IRS, University of Southern Denmark, Vejle, Denmark
| | - Pia Rosgaard Jensen
- Department of Clinical Cell Biology (KCB), Vejle Hospital - Lillebaelt Hospital, IRS, University of Southern Denmark, Kabbeltoft 25, 7100, Vejle, Denmark
| | - Ragad Walid Alnaimi
- Department of Clinical Cell Biology (KCB), Vejle Hospital - Lillebaelt Hospital, IRS, University of Southern Denmark, Kabbeltoft 25, 7100, Vejle, Denmark
| | - Lars Rolighed
- Breast and Endocrine Section, Department of Surgery, Aarhus University Hospital, Aarhus, Denmark
| | - Lars H Engelholm
- The Finsen Laboratory, Rigshospitalet/Biotech Research and Innovation Centre (BRIC), University of Copenhagen, Copenhagen, Denmark
| | - Niels Marcussen
- Department of Clinical Pathology, Odense University Hospital, Odense, Denmark
| | - Thomas Levin Andersen
- Department of Clinical Cell Biology (KCB), Vejle Hospital - Lillebaelt Hospital, IRS, University of Southern Denmark, Kabbeltoft 25, 7100, Vejle, Denmark.
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48
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Beck-Broichsitter BE, Becker ST, Seitz H, Wiltfang J, Warnke PH. Endocultivation: Histomorphological effects of repetitive rhBMP-2 application into prefabricated hydroxyapatite scaffolds at extraskeletal sites. J Craniomaxillofac Surg 2015; 43:981-8. [DOI: 10.1016/j.jcms.2015.03.038] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2014] [Revised: 03/29/2015] [Accepted: 03/30/2015] [Indexed: 11/30/2022] Open
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49
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Lee JH, Pryce BA, Schweitzer R, Ryder MI, Ho SP. Differentiating zones at periodontal ligament-bone and periodontal ligament-cementum entheses. J Periodontal Res 2015; 50:870-80. [PMID: 26031604 DOI: 10.1111/jre.12281] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/14/2015] [Indexed: 01/09/2023]
Abstract
BACKGROUND AND OBJECTIVE The structural and functional integrity of bone-periodontal ligament (PDL)-cementum complex stems from the load-bearing attachment sites (entheses) between soft (PDL) and hard (bone, cementum) tissues. These attachment sites are responsible for the maintenance of a bone-PDL-cementum complex biomechanical function. The objective was to investigate changes in spatiotemporal expression of key biomolecules in developing and functionally active entheses. MATERIAL AND METHODS Multilabeling technique was performed on hemimandibles of 3 wk and 3 mo-old scleraxis-GFP transgenic mice for CD146, CD31, NG2, osterix and bone sialoprotein. Regions of dominant stretch within the PDL were evaluated by identifying directionality of collagen fibrils, PDL fibroblasts and PDL cell cytoskeleton. RESULTS CD146+ cells adjacent to CD31+ vasculature were identified at PDL-bone enthesis. NG2+ cells were located at coronal bone-PDL and apical cementum-PDL entheses in the 3-wk-old group, but at 3 mo, NG2 was positive at the entheses of the apical region and alveolar crest. NG2 and osterix were colocalized at the osteoid and cementoid regions of the PDL-bone and PDL-cementum entheses. Bone sialoprotein was prominent at the apical region of 3-wk-old mice. The directionality of collagen fibers, fibroblasts and their cytoskeleton overlapped, except in the apical region of 3 wk. CONCLUSION Colocalization of biomolecules at zones of the PDL adjacent to attachment sites may be essential for the formation of precementum and osteoid interfaces at a load-bearing bone-PDL-tooth fibrous joint. Biophysical cues resulting from development and function can regulate recruitment and differentiation of stem cells potentially from a vascular origin toward osteo- and cemento-blastic lineages at the PDL-bone and PDL-cementum entheses. Investigating the coupled effect of biophysical and biochemical stimuli leading to cell differentiation at the functional attachment sites is critical for developing regeneration strategies to enable functional reconstruction of the periodontal complex.
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Affiliation(s)
- J-H Lee
- Division of Biomaterials and Bioengineering, Department of Preventive and Restorative Dental Sciences, University of California at San Francisco, San Francisco, CA, USA
| | - B A Pryce
- Portland Shriner's Research Center, Oregon Health & Science University, Portland, OR, USA
| | - R Schweitzer
- Portland Shriner's Research Center, Oregon Health & Science University, Portland, OR, USA
| | - M I Ryder
- Division of Periodontology, Department of Orofacial Sciences, University of California at San Francisco, San Francisco, CA, USA
| | - S P Ho
- Division of Biomaterials and Bioengineering, Department of Preventive and Restorative Dental Sciences, University of California at San Francisco, San Francisco, CA, USA
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50
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Abstract
After it was proposed that the osteoblast lineage controlled the formation of osteoclasts, cell culture methods were developed that established this to be the case. Evidence was obtained that cytokines and hormones that promote osteoclast formation act first on osteoblast lineage cells to promote the production of a membrane-bound regulator of osteoclastogenesis. This proved to be receptor activator of NF-kB ligand (RANKL) a member of the tumor necrosis factor ligand family that acts upon its receptor RANK in the hematopoietic lineage, with interaction restricted by a decoy soluble receptor osteoprotegerin (OPG), also a product of the osteoblast lineage. The physiological roles of these factors were established through genetic and pharmacological studies, have led to a new physiology of bone, with complete revision of older ideas over the last 15 years, ultimately leading to the development of new pharmaceutical agents for bone disease.
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Affiliation(s)
- T John Martin
- Department of Medicine at St. Vincent's Hospital, St. Vincent's Institute of Medical Research and The University of Melbourne, 9 Princes St, Fitzroy, VIC, 3065, Australia,
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