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Liu Z, Wang Q, Zhang J, Qi S, Duan Y, Li C. The Mechanotransduction Signaling Pathways in the Regulation of Osteogenesis. Int J Mol Sci 2023; 24:14326. [PMID: 37762629 PMCID: PMC10532275 DOI: 10.3390/ijms241814326] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Revised: 09/14/2023] [Accepted: 09/19/2023] [Indexed: 09/29/2023] Open
Abstract
Bones are constantly exposed to mechanical forces from both muscles and Earth's gravity to maintain bone homeostasis by stimulating bone formation. Mechanotransduction transforms external mechanical signals such as force, fluid flow shear, and gravity into intracellular responses to achieve force adaptation. However, the underlying molecular mechanisms on the conversion from mechanical signals into bone formation has not been completely defined yet. In the present review, we provide a comprehensive and systematic description of the mechanotransduction signaling pathways induced by mechanical stimuli during osteogenesis and address the different layers of interconnections between different signaling pathways. Further exploration of mechanotransduction would benefit patients with osteoporosis, including the aging population and postmenopausal women.
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Affiliation(s)
- Zhaoshuo Liu
- School of Engineering Medicine, Beihang University, Beijing 100191, China
- School of Biological Science and Medical Engineering, Beihang University, Beijing 100191, China
| | - Qilin Wang
- School of Engineering Medicine, Beihang University, Beijing 100191, China
- School of Biological Science and Medical Engineering, Beihang University, Beijing 100191, China
| | - Junyou Zhang
- School of Engineering Medicine, Beihang University, Beijing 100191, China
- School of Biological Science and Medical Engineering, Beihang University, Beijing 100191, China
| | - Sihan Qi
- School of Engineering Medicine, Beihang University, Beijing 100191, China
- School of Biological Science and Medical Engineering, Beihang University, Beijing 100191, China
| | - Yingying Duan
- School of Engineering Medicine, Beihang University, Beijing 100191, China
- School of Biological Science and Medical Engineering, Beihang University, Beijing 100191, China
| | - Chunyan Li
- School of Engineering Medicine, Beihang University, Beijing 100191, China
- School of Biological Science and Medical Engineering, Beihang University, Beijing 100191, China
- Key Laboratory of Big Data-Based Precision Medicine (Ministry of Industry and Information Technology), Beihang University, Beijing 100191, China
- Beijing Advanced Innovation Center for Big Data-Based Precision Medicine, Beihang University, Beijing 100191, China
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2
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Skorupan N, Palestino Dominguez M, Ricci SL, Alewine C. Clinical Strategies Targeting the Tumor Microenvironment of Pancreatic Ductal Adenocarcinoma. Cancers (Basel) 2022; 14:4209. [PMID: 36077755 PMCID: PMC9454553 DOI: 10.3390/cancers14174209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Revised: 08/23/2022] [Accepted: 08/25/2022] [Indexed: 12/04/2022] Open
Abstract
Pancreatic cancer has a complex tumor microenvironment which engages in extensive crosstalk between cancer cells, cancer-associated fibroblasts, and immune cells. Many of these interactions contribute to tumor resistance to anti-cancer therapies. Here, new therapeutic strategies designed to modulate the cancer-associated fibroblast and immune compartments of pancreatic ductal adenocarcinomas are described and clinical trials of novel therapeutics are discussed. Continued advances in our understanding of the pancreatic cancer tumor microenvironment are generating stromal and immune-modulating therapeutics that may improve patient responses to anti-tumor treatment.
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Affiliation(s)
- Nebojsa Skorupan
- Laboratory of Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
- Medical Oncology Program, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Mayrel Palestino Dominguez
- Laboratory of Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Samuel L. Ricci
- Laboratory of Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Christine Alewine
- Laboratory of Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
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3
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Dao L, Blaue C, Franz CM. Integrin α 2β 1 as a negative regulator of the laminin receptors α 6β 1 and α 6β 4. Micron 2021; 148:103106. [PMID: 34171483 DOI: 10.1016/j.micron.2021.103106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 04/30/2021] [Accepted: 06/17/2021] [Indexed: 10/21/2022]
Abstract
Integrin α2β1 is a widely expressed collagen I receptor which also mediates laminin-111 binding in some cell types, but the functional relevance of collagen versus laminin binding for different cell types is poorly understood. Here we use AFM-based singe-cell force spectroscopy (SCFS) to compare α2β1-mediated adhesion strength to collagen and laminin in different cell types. Chinese Hamster Ovary (CHO) cells stably expressing integrin α2β1 (CHO-A2) displayed enhanced adhesion to collagen, but weak adhesion to laminin, consistent with a role of α2β1 as a receptor only for collagen in these cells. Inversely, the α2β1-deficient CHO wildtype cells (CHO-WT) showed weak adhesion to collagen, but strong adhesion to laminin-111, in turn suggesting that integrin α2β1 expression suppresses laminin binding. Analogous results were obtained in a pair of SAOS-2 human osteosarcoma cell lines. Again, wildtype cells (SAOS-WT) adhered strongly to laminin and poorly to collagen, while expression of integrin α2β1 (SAOS-A2) induced strong adhesion to collagen, but reduced adhesion to laminin. Expression of α2β1 also shifted cell spreading preference from laminin to collagen and suppressed laminin-dependent transmigration. In agreement with reduced laminin adhesion, α2β1 expression downregulated transcription and expression of integrin subunits α6 and β4, components of the main laminin-111 binding receptors integrin α6β1 and α6β4 in these cells. Integrin α6 and β4 expression was also reduced when α2 expression was chemically induced using tetradecanoyl-phorbol-acetate (TPA). Our results thus show that integrin α2β1 expression negatively regulates integrin α6β1 and α6β4-mediated adhesion, spreading and invasion on laminin in different cancer cell types. In contrast to SAOS-WT, but similar to SAOS-A2 osteosarcoma cells, primary Human osteoblasts (HOB) cells express α2 but only low levels of β4 integrin, preferentially adhere to and spread on collagen over laminin and show suppressed laminin-dependent transmigration. By enhancing collagen binding directly and suppressing laminin binding indirectly through laminin receptor downregulation, α2β1 expression may thus re-direct migrating cancer cells from laminin-rich to collagenous tissues and partially revert osteosarcoma cells towards an untransformed phenotype.
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Affiliation(s)
- Lu Dao
- Center for Functional Nanostructures, Karlsruher Institut für Technologie (KIT), Wolfgang-Gaede-Strasse 1a, 76131, Karlsruhe, Germany
| | - Carina Blaue
- Center for Functional Nanostructures, Karlsruher Institut für Technologie (KIT), Wolfgang-Gaede-Strasse 1a, 76131, Karlsruhe, Germany
| | - Clemens M Franz
- Center for Functional Nanostructures, Karlsruher Institut für Technologie (KIT), Wolfgang-Gaede-Strasse 1a, 76131, Karlsruhe, Germany; WPI Nano Life Science Institute, Kanazawa University, Kakuma-machi, Kanazawa, Japan.
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4
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Dhavalikar P, Robinson A, Lan Z, Jenkins D, Chwatko M, Salhadar K, Jose A, Kar R, Shoga E, Kannapiran A, Cosgriff-Hernandez E. Review of Integrin-Targeting Biomaterials in Tissue Engineering. Adv Healthc Mater 2020; 9:e2000795. [PMID: 32940020 PMCID: PMC7960574 DOI: 10.1002/adhm.202000795] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Revised: 08/27/2020] [Indexed: 12/12/2022]
Abstract
The ability to direct cell behavior has been central to the success of numerous therapeutics to regenerate tissue or facilitate device integration. Biomaterial scientists are challenged to understand and modulate the interactions of biomaterials with biological systems in order to achieve effective tissue repair. One key area of research investigates the use of extracellular matrix-derived ligands to target specific integrin interactions and induce cellular responses, such as increased cell migration, proliferation, and differentiation of mesenchymal stem cells. These integrin-targeting proteins and peptides have been implemented in a variety of different polymeric scaffolds and devices to enhance tissue regeneration and integration. This review first presents an overview of integrin-mediated cellular processes that have been identified in angiogenesis, wound healing, and bone regeneration. Then, research utilizing biomaterials are highlighted with integrin-targeting motifs as a means to direct these cellular processes to enhance tissue regeneration. In addition to providing improved materials for tissue repair and device integration, these innovative biomaterials provide new tools to probe the complex processes of tissue remodeling in order to enhance the rational design of biomaterial scaffolds and guide tissue regeneration strategies.
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Affiliation(s)
- Prachi Dhavalikar
- Department of Biomedical Engineering, University of Texas at Austin, Austin, TX, 78712, USA
| | - Andrew Robinson
- Department of Biomedical Engineering, University of Texas at Austin, Austin, TX, 78712, USA
| | - Ziyang Lan
- Department of Biomedical Engineering, University of Texas at Austin, Austin, TX, 78712, USA
| | - Dana Jenkins
- Department of Biomedical Engineering, University of Texas at Austin, Austin, TX, 78712, USA
| | - Malgorzata Chwatko
- Department of Biomedical Engineering, University of Texas at Austin, Austin, TX, 78712, USA
| | - Karim Salhadar
- Department of Biomedical Engineering, University of Texas at Austin, Austin, TX, 78712, USA
| | - Anupriya Jose
- Department of Biomedical Engineering, University of Texas at Austin, Austin, TX, 78712, USA
| | - Ronit Kar
- Department of Biomedical Engineering, University of Texas at Austin, Austin, TX, 78712, USA
| | - Erik Shoga
- Department of Biomedical Engineering, University of Texas at Austin, Austin, TX, 78712, USA
| | - Aparajith Kannapiran
- Department of Biomedical Engineering, University of Texas at Austin, Austin, TX, 78712, USA
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Charlier E, Deroyer C, Neuville S, Plener Z, Malaise O, Ciregia F, Gillet P, Reuter G, Salvé M, Withofs N, Hustinx R, de Seny D, Malaise MG. Toward diagnostic relevance of the α Vβ 5, α Vβ 3, and α Vβ 6 integrins in OA: expression within human cartilage and spinal osteophytes. Bone Res 2020; 8:35. [PMID: 33083095 PMCID: PMC7527564 DOI: 10.1038/s41413-020-00110-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Revised: 05/06/2020] [Accepted: 06/08/2020] [Indexed: 12/14/2022] Open
Abstract
We previously reported 18FPRGD2 uptake by the coxofemoral lining, intervertebral discs and facet joint osteophytes in OA using PET/SCAN imaging. However, the molecular mechanism by which the PRGD2 tracer interacts with joint tissues and osteophytes in OA remains unclear. As PRGD2 ligands are expected to belong to the RGD-specific integrin family, the purpose of this study was (i) to determine which integrin complexes display the highest affinity for PRGD2-based ligands, (ii) to analyze integrin expression in relevant tissues, and (iii) to test integrin regulation in chondrocytes using OA-related stimuli to increase the levels of fibrosis and ossification markers. To this end, the affinity of PRGD2-based ligands for five heterodimeric integrins was measured by competition with 125I-echistatin. In situ analyses were performed in human normal vs. OA cartilage and spinal osteophytes. Osteophytes were characterized by (immuno-)histological staining. Integrin subunit expression was tested in chondrocytes undergoing dedifferentiation, osteogenic differentiation, and inflammatory stimulation. The integrins αVβ5, αVβ3, and αVβ6 presented the highest affinity for PRGD2-based ligands. In situ, the expression of these integrins was significantly increased in OA compared to normal cartilage. Within osteophytes, the mean integrin expression score was significantly higher in blood vessels, fibrous areas, and cells from the bone lining than in osteocytes and cartilaginous zones. In vitro, the levels of integrin subunits were significantly increased during chondrocyte dedifferentiation (except for β6), fibrosis, and osteogenic differentiation as well as under inflammatory stimuli. In conclusion, anatomical zones (such as OA cartilage, intervertebral discs, and facet joint osteophytes) previously reported to show PRGD2 ligand uptake in vivo expressed increased levels of αVβ5, αVβ3, and β6 integrins, whose subunits are modulated in vitro by OA-associated conditions that increase fibrosis, inflammation, and osteogenic differentiation. These results suggest that the increased levels of integrins in OA compared to normal tissues favor PRGD2 uptake and might explain the molecular mechanism of OA imaging using the PRGD2-based ligand PET/CT.
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Affiliation(s)
- Edith Charlier
- Laboratory of Rheumatology, GIGA-I3, CHULiège, ULiège, Liège, Belgium
| | - Céline Deroyer
- Laboratory of Rheumatology, GIGA-I3, CHULiège, ULiège, Liège, Belgium
| | - Sophie Neuville
- Laboratory of Rheumatology, GIGA-I3, CHULiège, ULiège, Liège, Belgium
| | - Zelda Plener
- Laboratory of Rheumatology, GIGA-I3, CHULiège, ULiège, Liège, Belgium
| | - Olivier Malaise
- Laboratory of Rheumatology, GIGA-I3, CHULiège, ULiège, Liège, Belgium
| | - Federica Ciregia
- Laboratory of Rheumatology, GIGA-I3, CHULiège, ULiège, Liège, Belgium
| | | | - Gilles Reuter
- Department of Neurosurgery, CHULiège, Liège, Belgium
| | - Mallory Salvé
- Department of Nuclear Medicine, CHULiège, Liège, Belgium
| | - Nadia Withofs
- Department of Nuclear Medicine, CHULiège, Liège, Belgium
| | - Roland Hustinx
- Department of Nuclear Medicine, CHULiège, Liège, Belgium
| | - Dominique de Seny
- Laboratory of Rheumatology, GIGA-I3, CHULiège, ULiège, Liège, Belgium
| | - Michel G. Malaise
- Laboratory of Rheumatology, GIGA-I3, CHULiège, ULiège, Liège, Belgium
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Loss of p53 in mesenchymal stem cells promotes alteration of bone remodeling through negative regulation of osteoprotegerin. Cell Death Differ 2020; 28:156-169. [PMID: 32694652 PMCID: PMC7853126 DOI: 10.1038/s41418-020-0590-4] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Revised: 07/08/2020] [Accepted: 07/09/2020] [Indexed: 12/26/2022] Open
Abstract
p53 plays a pivotal role in controlling the differentiation of mesenchymal stem cells (MSCs) by regulating genes involved in cell cycle and early steps of differentiation process. In the context of osteogenic differentiation of MSCs and bone homeostasis, the osteoprotegerin/receptor activator of NF-κB ligand/receptor activator of NF-κB (OPG/RANKL/RANK) axis is a critical signaling pathway. The absence or loss of function of p53 has been implicated in aberrant osteogenic differentiation of MSCs that results in higher bone formation versus erosion, leading to an unbalanced bone remodeling. Here, we show by microCT that mice with p53 deletion systemically or specifically in mesenchymal cells possess significantly higher bone density than their respective littermate controls. There is a negative correlation between p53 and OPG both in vivo by analysis of serum from p53+/+, p53+/-, and p53-/- mice and in vitro by p53 knockdown and ChIP assay in MSCs. Notably, high expression of Opg or its combination with low level of p53 are prominent features in clinical cancer lesion of osteosarcoma and prostate cancer respectively, which correlate with poor survival. Intra-bone marrow injection of prostate cancer cells, together with androgen can suppress p53 expression and enhance local Opg expression, leading to an enhancement of bone density. Our results support the notion that MSCs, as osteoblast progenitor cells and one major component of bone microenvironment, represent a cellular source of OPG, whose amount is regulated by the p53 status. It also highlights a key role for the p53-OPG axis in regulating the cancer associated bone remodeling.
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Lee HM, Seo SR, Kim J, Kim MK, Seo H, Kim KS, Jang YJ, Ryu CJ. Expression dynamics of integrin α2, α3, and αV upon osteogenic differentiation of human mesenchymal stem cells. Stem Cell Res Ther 2020; 11:210. [PMID: 32493499 PMCID: PMC7268774 DOI: 10.1186/s13287-020-01714-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Revised: 04/06/2020] [Accepted: 05/07/2020] [Indexed: 02/06/2023] Open
Abstract
Background The differentiation of human mesenchymal stem cells (hMSCs) into osteoblasts (OBs) is a prerequisite for bone formation. However, little is known about the definitive surface markers for OBs during osteogenesis. Methods To study the surface markers on OBs, we generated and used monoclonal antibodies (MAbs) against surface molecules on transforming growth factor-β1 (TGF-β1)-treated cancer cells. The generated MAbs were further selected toward expression changes on hMSCs cultured with TGF-β1/bone morphogenetic protein-2 (BMP-2) or osteogenic differentiation medium (ODM) by flow cytometry. Immunoprecipitation and mass spectrometry were performed to identify target antigens of selected MAbs. Expression changes of the target antigens were evaluated in hMSCs, human periodontal ligament cells (hPDLCs), and human dental pulp cells (hDPCs) during osteogenic and adipogenic differentiation by quantitative polymerase chain reaction (qPCR) and flow cytometry. hMSCs were also sorted by the MAbs using magnetic-activated cell sorting system, and osteogenic potential of sorted cells was evaluated via Alizarin Red S (ARS) staining and qPCR. Results The binding reactivity of MR14-E5, one of the MAbs, was downregulated in hMSCs with ODM while the binding reactivity of ER7-A7, ER7-A8, and MR1-B1 MAbs was upregulated. Mass spectrometry and overexpression identified that MR14-E5, ER7-A7/ER7-A8, and MR1-B1 recognized integrin α2, α3, and αV, respectively. Upon osteogenic differentiation of hMSCs, the expression of integrin α2 was drastically downregulated, but the expression of integrin α3 and αV was upregulated in accordance with upregulation of osteogenic markers. Expression of integrin α3 and αV was also upregulated in hPDLCs and hDPCs during osteogenic differentiation. Cell sorting showed that integrin αV-high hMSCs have a greater osteogenic potential than integrin αV-low hMSCs upon the osteogenic differentiation of hMSCs. Cell sorting further revealed that the surface expression of integrin αV is more dramatically induced even in integrin αV-low hMSCs. Conclusion These findings suggest that integrin α3 and αV induction is a good indicator of OB differentiation. These findings also shed insight into the expression dynamics of integrins upon osteogenic differentiation of hMSCs and provide the reason why different integrin ligands are required for OB differentiation of hMSCs.
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Affiliation(s)
- Hyun Min Lee
- Department of Integrative Bioscience and Biotechnology, Institute of Anticancer Medicine Development, Sejong University, 209 Neungdong-ro, Gwangjin-gu, Seoul, 05006, Korea
| | - Se-Ri Seo
- Department of Integrative Bioscience and Biotechnology, Institute of Anticancer Medicine Development, Sejong University, 209 Neungdong-ro, Gwangjin-gu, Seoul, 05006, Korea
| | - Jeeseung Kim
- Department of Integrative Bioscience and Biotechnology, Institute of Anticancer Medicine Development, Sejong University, 209 Neungdong-ro, Gwangjin-gu, Seoul, 05006, Korea
| | - Min Kyu Kim
- Department of Integrative Bioscience and Biotechnology, Institute of Anticancer Medicine Development, Sejong University, 209 Neungdong-ro, Gwangjin-gu, Seoul, 05006, Korea
| | - Hyosun Seo
- Department of Integrative Bioscience and Biotechnology, Institute of Anticancer Medicine Development, Sejong University, 209 Neungdong-ro, Gwangjin-gu, Seoul, 05006, Korea
| | - Kyoung Soo Kim
- Department of Clinical Pharmacology and Therapeutics, Kyung Hee University School of Medicine, Seoul, 02447, Korea
| | - Young-Joo Jang
- Department of Nanobiomedical Science, BK21 PLUS NBM Global Research Center for Regenerative Medicine, College of Dentistry, Dankook University, Cheonan, 330-714, Korea.
| | - Chun Jeih Ryu
- Department of Integrative Bioscience and Biotechnology, Institute of Anticancer Medicine Development, Sejong University, 209 Neungdong-ro, Gwangjin-gu, Seoul, 05006, Korea.
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Pieters BCH, Cappariello A, van den Bosch MHJ, van Lent PLEM, Teti A, van de Loo FAJ. Macrophage-Derived Extracellular Vesicles as Carriers of Alarmins and Their Potential Involvement in Bone Homeostasis. Front Immunol 2019; 10:1901. [PMID: 31440259 PMCID: PMC6694442 DOI: 10.3389/fimmu.2019.01901] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Accepted: 07/26/2019] [Indexed: 02/04/2023] Open
Abstract
Extracellular vesicles are a heterogeneous group of cell-derived membranous structures, which facilitate intercellular communication. Recent studies have highlighted the importance of extracellular vesicles in bone homeostasis, as mediators of crosstalk between different bone-resident cells. Osteoblasts and osteoclasts are capable of releasing various types of extracellular vesicles that promote both osteogenesis, as well as, osteoclastogenesis, maintaining bone homeostasis. However, the contribution of immune cell-derived extracellular vesicles in bone homeostasis remains largely unknown. Recent proteomic studies showed that alarmins are abundantly present in/on macrophage-derived EVs. In this review we will describe these alarmins in the context of bone matrix regulation and discuss the potential contribution macrophage-derived EVs may have in this process.
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Affiliation(s)
- Bartijn C H Pieters
- Experimental Rheumatology, Radboud University Medical Center, Nijmegen, Netherlands
| | - Alfredo Cappariello
- Research Laboratories - Department of Oncohematology IRCCS Bambino Gesù Children's Hospital, Rome, Italy
| | | | - Peter L E M van Lent
- Experimental Rheumatology, Radboud University Medical Center, Nijmegen, Netherlands
| | - Anna Teti
- Department of Biotechnological and Applied Clinical Sciences, University of L'Aquila, L'Aquila, Italy
| | - Fons A J van de Loo
- Experimental Rheumatology, Radboud University Medical Center, Nijmegen, Netherlands
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Abstract
PURPOSE OF REVIEW Osteocytes are the main mechanosensitive cells in bone. Integrin-based adhesions have been shown to facilitate mechanotransduction, and therefore play an important role in load-induced bone formation. This review outlines the role of integrins in osteocyte function (cell adhesion, signalling, and mechanotransduction) and possible role in disease. RECENT FINDINGS Both β1 and β3 integrins subunits have been shown to be required for osteocyte mechanotransduction. Antagonism of these integrin subunits in osteocytes resulted in impaired responses to fluid shear stress. Various disease states (osteoporosis, osteoarthritis, bone metastases) have been shown to result in altered integrin expression and function. Osteocyte integrins are required for normal cell function, with dysregulation of integrins seen in disease. Understanding the mechanism of faulty integrins in disease may aid in the creation of novel therapeutic approaches.
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Affiliation(s)
- Ivor P Geoghegan
- Department of Mechanical and Biomedical Engineering, Mechanobiology and Medical Device Research Group (MMDRG), Biomedical Engineering, National University of Ireland, Galway, Ireland
- Centre for Research in Medical Devices (CÚRAM), National University of Ireland, Galway, Ireland
| | - David A Hoey
- Centre for Research in Medical Devices (CÚRAM), National University of Ireland, Galway, Ireland
- Trinity Centre for Bioengineering, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin 2, Ireland
- Department of Mechanical and Manufacturing Engineering, School of Engineering, Trinity College Dublin, Dublin 2, Ireland
- Advanced Materials and Bioengineering Research Centre, Trinity College Dublin & RCSI, Dublin 2, Ireland
| | - Laoise M McNamara
- Department of Mechanical and Biomedical Engineering, Mechanobiology and Medical Device Research Group (MMDRG), Biomedical Engineering, National University of Ireland, Galway, Ireland.
- Centre for Research in Medical Devices (CÚRAM), National University of Ireland, Galway, Ireland.
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Feng S, Wu ZX, Zhao Z, Liu J, Sun K, Guo C, Wang H, Wu Z. Engineering of Bone- and CD44-Dual-Targeting Redox-Sensitive Liposomes for the Treatment of Orthotopic Osteosarcoma. ACS APPLIED MATERIALS & INTERFACES 2019; 11:7357-7368. [PMID: 30682240 DOI: 10.1021/acsami.8b18820] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
This study aimed to develop an efficient step-by-step osteosarcoma (OS)-targeting liposome system functionalized with a redox-cleavable, bone- and cluster of differentiation 44 (CD44)-dual-targeting polymer. Furthermore, the effect of coadministration of a tumor-penetrating peptide, internalizing RGD (iRGD), was investigated. First, a bone-targeting moiety, alendronate (ALN), was conjugated with hyaluronic acid (HA), a ligand for CD44. This ALN-HA conjugate was coupled with DSPE-PEG2000-COOH through a bioreducible disulfide linker (-SS-) to obtain a functionalized lipid, ALN-HA-SS-L, to be postinserted into preformed liposomes loaded with doxorubicin (DOX). The roles of ALN, HA, and the redox sensitivity of the ALN-HA-SS-L liposomes (ALN-HA-SS-L-L) in the anti-OS effect were critically evaluated against various reference liposomal formulations (with only ALN, HA, or redox sensitivity). ALN-HA-SS-L-L displayed a zeta potential of -26.07 ± 0.32 mV and selectively disassembled in the presence of a reducing agent, 10 mM glutathione, which can be found in cancer cells. Compared to various reference liposomes, ALN-HA-SS-L-L/DOX had significantly higher cytotoxicity to human OS MG-63 cells alongside high and rapid cellular uptake. In the orthotopic OS nude mouse models, ALN-HA-SS-L-L/DOX showed remarkable tumor growth suppression and prolonged survival time. This result was further improved by the coadministration of iRGD. The antitumor effects of various liposomes were ranked in the same order as the degree of tumor biodistribution shown by in vivo/ex vivo imaging: ALN-HA-SS-L-L coadministered with iRGD > ALN-HA-SS-L-L > HA-SS-L-L > HA-L-L > PEG-L> free drug. ALN-HA-SS-L-L/DOX also reduced the cardiotoxicity of DOX and lung metastases. Overall, this study demonstrated that ALN-HA-SS-L-L/DOX, equipped with bone- and CD44-dual-targeting abilities and redox sensitivity, could be a promising OS-targeted therapy. The efficacy could also be augmented by coadministration of iRGD.
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Affiliation(s)
- Shuaishuai Feng
- School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation (Yantai University), Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in University of Shandong , Yantai University , Yantai 264005 , PR China
| | - Zi-Xin Wu
- Qingdao Municipal Hospital , Qingdao 266071 Shandong Province , PR China
| | - Ziyan Zhao
- School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation (Yantai University), Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in University of Shandong , Yantai University , Yantai 264005 , PR China
| | - Jinhu Liu
- School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation (Yantai University), Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in University of Shandong , Yantai University , Yantai 264005 , PR China
| | - Kaoxiang Sun
- School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation (Yantai University), Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in University of Shandong , Yantai University , Yantai 264005 , PR China
| | - Chuanyou Guo
- Qingdao Municipal Hospital , Qingdao 266071 Shandong Province , PR China
| | - Hongbo Wang
- School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation (Yantai University), Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in University of Shandong , Yantai University , Yantai 264005 , PR China
| | - Zimei Wu
- School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation (Yantai University), Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs in University of Shandong , Yantai University , Yantai 264005 , PR China
- School of Pharmacy , University of Auckland , Auckland 1142 , New Zealand
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Wallstabe L, Mades A, Frenz S, Einsele H, Rader C, Hudecek M. CAR T cells targeting α vβ 3 integrin are effective against advanced cancer in preclinical models. ACTA ACUST UNITED AC 2018; 1. [PMID: 30420973 DOI: 10.1002/acg2.11] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Objective Integrins are heterodimeric receptors that convey cell-to-cell and cell-to-matrix interactions. Integrin αvβ3 is expressed in several tumour entities including melanoma, glioblastoma, breast, pancreatic and prostate cancer, where it promotes tumour cell survival and metastasis. Here, we generated αvβ3-specific chimeric antigen receptor (CAR) T-cells and analysed their antitumour function in pre-clinical models in vitro and in vivo. Methods αvβ3-CARs comprising a super-humanised hLM609 targeting domain with either high or low affinity (hLM609v7, K d = 3 nM vs. hLM609v11, K d = 160 nM) and equipped with either a long or a short IgG4-Fc extracellular spacer (229 vs. 12 amino acids) were expressed in CD8+ and CD4+ T-cells through lentiviral transduction. Results αvβ3-CAR T-cells eliminated αvβ3-positive tumour cells rapidly and specifically, produced IFN-γ and IL-2 (CD4+ > CD8+) and exhibited productive proliferation. In vitro, we observed the strongest reactivity with the higher-affinity hLM609v7 αvβ3-CAR in the short spacer configuration, consistent with the tumour membrane-distal localization of the hLM609 epitope. In a murine xenograft model of metastatic A-375 melanoma, the strongest antitumour effect was mediated by the lower-affinity hLM609v11 αvβ3-CAR. Notably, a single administration of hLM609v11 αvβ3-CAR T-cells was able to induce complete elimination of melanoma lesions, leading to long-term tumour-free survival. Conclusions These data establish αvβ3 integrin as a novel target for CAR T-cell immunotherapy, and affirm our previous notion that binding domain affinity and spacer length can be calibrated to augment CAR reactivity. Clinical implications αvβ3-CAR T-cells have therapeutic potential in several prevalent solid tumours, including melanoma and triple-negative breast cancer.
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Affiliation(s)
- Lars Wallstabe
- Medizinische Klinik und Poliklinik II, Universitätsklinikum Würzburg, Würzburg, Germany
| | - Andreas Mades
- Medizinische Klinik und Poliklinik II, Universitätsklinikum Würzburg, Würzburg, Germany
| | - Silke Frenz
- Medizinische Klinik und Poliklinik II, Universitätsklinikum Würzburg, Würzburg, Germany
| | - Hermann Einsele
- Medizinische Klinik und Poliklinik II, Universitätsklinikum Würzburg, Würzburg, Germany
| | - Christoph Rader
- Department of Immunology and Microbiology, The Scripps Research Institute, Jupiter, Florida, USA
| | - Michael Hudecek
- Medizinische Klinik und Poliklinik II, Universitätsklinikum Würzburg, Würzburg, Germany
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12
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Martín-Moldes Z, Ebrahimi D, Plowright R, Dinjaski N, Perry CC, Buehler MJ, Kaplan DL. Intracellular Pathways Involved in Bone Regeneration Triggered by Recombinant Silk-silica Chimeras. ADVANCED FUNCTIONAL MATERIALS 2018; 28:1702570. [PMID: 30140193 PMCID: PMC6101667 DOI: 10.1002/adfm.201702570] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Biomineralization at the organic-inorganic interface is critical to many biology material functions in vitro and in vivo. Recombinant silk-silica fusion peptides are organic-inorganic hybrid material systems that can be effectively used to study and control biologically-mediated mineralization due to the genetic basis of sequence control. However, to date, the mechanisms by which these functionalized silk-silica proteins trigger the differentiation of human mesenchymal stem cells (hMSCs) to osteoblasts remain unknown. To address this challenge, we analyzed silk-silica surfaces for silica-hMSC receptor binding and activation, and the intracellular pathways involved in the induction of osteogenesis on these bioengineered biomaterials. The induction of gene expression of αVβ3 integrin, all three Mitogen-activated Protein Kinsases (MAPKs) as well as c-Jun, Runt-related Transcription Factor 2 (Runx2) and osteoblast marker genes was demonstrated upon growth of the hMSCs on the silk-silica materials. This induction of key markers of osteogenesis correlated with the content of silica on the materials. Moreover, computational simulations were performed for silk/silica-integrin binding which showed activation of αVβ3 integrin in contact with silica. This integrated computational and experimental approach provides insight into interactions that regulate osteogenesis towards more efficient biomaterial designs.
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Affiliation(s)
- Zaira Martín-Moldes
- Department of Biomedical Engineering, Tufts University, Medford, MA, 02155, USA
| | - Davoud Ebrahimi
- Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Robyn Plowright
- Biomolecular and Materials Interface Research Group, Interdisciplinary Biomedical Research Centre, School of Science and Technology, Nottingham Trent University, Clifton Lane, Nottingham NG11 8NS, UK
| | - Nina Dinjaski
- Department of Biomedical Engineering, Tufts University, Medford, MA, 02155, USA; Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Carole C Perry
- Biomolecular and Materials Interface Research Group, Interdisciplinary Biomedical Research Centre, School of Science and Technology, Nottingham Trent University, Clifton Lane, Nottingham NG11 8NS, UK
| | - Markus J Buehler
- Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - David L Kaplan
- Department of Biomedical Engineering, Tufts University, Medford, MA, 02155, USA
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13
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Maria S, Samsonraj RM, Munmun F, Glas J, Silvestros M, Kotlarczyk MP, Rylands R, Dudakovic A, van Wijnen AJ, Enderby LT, Lassila H, Dodda B, Davis VL, Balk J, Burow M, Bunnell BA, Witt-Enderby PA. Biological effects of melatonin on osteoblast/osteoclast cocultures, bone, and quality of life: Implications of a role for MT2 melatonin receptors, MEK1/2, and MEK5 in melatonin-mediated osteoblastogenesis. J Pineal Res 2018; 64:10.1111/jpi.12465. [PMID: 29285799 PMCID: PMC6711668 DOI: 10.1111/jpi.12465] [Citation(s) in RCA: 109] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Accepted: 12/13/2017] [Indexed: 01/05/2023]
Abstract
The Melatonin Osteoporosis Prevention Study (MOPS) demonstrated that nightly melatonin resulted in a time-dependent decrease in equilibrium ratios of serum osteoclasts and osteoblasts in perimenopausal women. This study examines mechanisms related to the ratios of osteoblasts and osteoclasts using coculture models (transwell or layered) of human mesenchymal stem cell (MSC) and human peripheral blood monocytes (PBMCs). Human MSC/PBMC cocultures exposed to melatonin in osteogenic (OS+) medium for 21 days induced osteoblast differentiation and mineralization; however, only in layered cocultures did melatonin inhibit osteoclastogenesis. Melatonin effects were mediated through MT2 melatonin receptors, MEK1/2, and MEK5. In layered but not transwell cocultures, melatonin increased OPG:RANKL ratios by inhibiting RANKL, suggesting that contact with osteoclasts during osteoblastogenesis inhibits RANKL secretion. Melatonin modulated expression of ERK1/2, ERK5, β1 integrin, GLUT4, and IRβ that was dependent upon the type of coculture; however, in both cultures, melatonin increased RUNX2 and decreased PPARγ expression, indicating a role for metabolic processes that control osteogenic vs adipogenic cell fates of MSCs. Furthermore, melatonin also has osteoblast-inducing effects on human adipose-derived MSCs. In vivo, one-year nightly melatonin (15 mg/L) given to neu female mice in their drinking water increased pErk1/2, pErk5, Runx2, and Opg and Rankl levels in bone consistent with melatonin's already reported bone-enhancing effects. Finally, analysis of daily logs from the MOPS demonstrated a significant improvement in mood and perhaps sleep quality in women receiving melatonin vs placebo. The osteoblast-inducing, bone-enhancing effects of melatonin and improvement in quality of life suggest that melatonin is a safe and effective bone loss therapy.
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Affiliation(s)
- Sifat Maria
- Division of Pharmaceutical, Administrative and Social Sciences, Duquesne University School of Pharmacy, Pittsburgh, PA, USA
| | | | - Fahima Munmun
- Division of Pharmaceutical, Administrative and Social Sciences, Duquesne University School of Pharmacy, Pittsburgh, PA, USA
| | - Jessica Glas
- Division of Pharmaceutical, Administrative and Social Sciences, Duquesne University School of Pharmacy, Pittsburgh, PA, USA
| | - Maria Silvestros
- Division of Pharmaceutical, Administrative and Social Sciences, Duquesne University School of Pharmacy, Pittsburgh, PA, USA
| | - Mary P. Kotlarczyk
- Division of Pharmaceutical, Administrative and Social Sciences, Duquesne University School of Pharmacy, Pittsburgh, PA, USA
| | - Ryan Rylands
- Division of Pharmaceutical, Administrative and Social Sciences, Duquesne University School of Pharmacy, Pittsburgh, PA, USA
| | - Amel Dudakovic
- Department of Orthopedic Surgery, Mayo Clinic, Rochester, MN, USA
| | | | | | - Holly Lassila
- Division of Clinical Sciences, Duquesne University School of Pharmacy, Pittsburgh, PA, USA
| | - Bala Dodda
- Division of Pharmaceutical, Administrative and Social Sciences, Duquesne University School of Pharmacy, Pittsburgh, PA, USA
| | - Vicki L. Davis
- Division of Pharmaceutical, Administrative and Social Sciences, Duquesne University School of Pharmacy, Pittsburgh, PA, USA
| | - Judy Balk
- West Penn/Allegheny Health System, Drexel University and Temple University, Pittsburgh, PA, USA
| | - Matt Burow
- Center for Stem Cell Research and Department of Pharmacology, Tulane University School of Medicine, New Orleans, LA, USA
| | - Bruce A. Bunnell
- Center for Stem Cell Research and Department of Pharmacology, Tulane University School of Medicine, New Orleans, LA, USA
| | - Paula A. Witt-Enderby
- Division of Pharmaceutical, Administrative and Social Sciences, Duquesne University School of Pharmacy, Pittsburgh, PA, USA
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14
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Vetrik M, Parizek M, Hadraba D, Kukackova O, Brus J, Hlidkova H, Komankova L, Hodan J, Sedlacek O, Slouf M, Bacakova L, Hruby M. Porous Heat-Treated Polyacrylonitrile Scaffolds for Bone Tissue Engineering. ACS APPLIED MATERIALS & INTERFACES 2018; 10:8496-8506. [PMID: 29437373 DOI: 10.1021/acsami.7b18839] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Heat-treated polyacrylonitrile (HT-PAN), also referred to as black orlon (BO), is a promising carbon-based material used for applications in tissue engineering and regenerative medicine. To the best of our knowledge, no such complex bone morphology-mimicking three-dimensional (3D) BO structure has been reported to date. We report that BO can be easily made into 3D cryogel scaffolds with porous structures, using succinonitrile as a porogen. The cryogels possess a porous morphology, similar to bone tissue. The prepared scaffolds showed strong osteoconductive activity, providing excellent support for the adhesion, proliferation, and mitochondrial activity of human bone-derived cells. This effect was more apparent in scaffolds prepared from a matrix with a higher content of PAN (i.e., 10% rather than 5%). The scaffolds with 10% of PAN also showed enhanced mechanical properties, as revealed by higher compressive modulus and higher compressive strength. Therefore, these scaffolds have a robust potential for use in bone tissue engineering.
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Affiliation(s)
- Miroslav Vetrik
- Institute of Macromolecular Chemistry of the Czech Academy of Sciences , Heyrovsky Sq. 2 , 162 06 Prague 6 , Czech Republic
| | - Martin Parizek
- Institute of Physiology of the Czech Academy of Sciences , Videnska 1083 , 14220 Prague 4 , Czech Republic
| | - Daniel Hadraba
- Institute of Physiology of the Czech Academy of Sciences , Videnska 1083 , 14220 Prague 4 , Czech Republic
| | - Olivia Kukackova
- Institute of Macromolecular Chemistry of the Czech Academy of Sciences , Heyrovsky Sq. 2 , 162 06 Prague 6 , Czech Republic
| | - Jiri Brus
- Institute of Macromolecular Chemistry of the Czech Academy of Sciences , Heyrovsky Sq. 2 , 162 06 Prague 6 , Czech Republic
| | - Helena Hlidkova
- Institute of Macromolecular Chemistry of the Czech Academy of Sciences , Heyrovsky Sq. 2 , 162 06 Prague 6 , Czech Republic
| | - Lucie Komankova
- Institute of Macromolecular Chemistry of the Czech Academy of Sciences , Heyrovsky Sq. 2 , 162 06 Prague 6 , Czech Republic
| | - Jiri Hodan
- Institute of Macromolecular Chemistry of the Czech Academy of Sciences , Heyrovsky Sq. 2 , 162 06 Prague 6 , Czech Republic
| | - Ondrej Sedlacek
- Institute of Macromolecular Chemistry of the Czech Academy of Sciences , Heyrovsky Sq. 2 , 162 06 Prague 6 , Czech Republic
| | - Miroslav Slouf
- Institute of Macromolecular Chemistry of the Czech Academy of Sciences , Heyrovsky Sq. 2 , 162 06 Prague 6 , Czech Republic
| | - Lucie Bacakova
- Institute of Physiology of the Czech Academy of Sciences , Videnska 1083 , 14220 Prague 4 , Czech Republic
| | - Martin Hruby
- Institute of Macromolecular Chemistry of the Czech Academy of Sciences , Heyrovsky Sq. 2 , 162 06 Prague 6 , Czech Republic
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15
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Beaufils C, Farlay D, Machuca-Gayet I, Fassier A, Zenker M, Freychet C, Bonnelye E, Bertholet-Thomas A, Ranchin B, Bacchetta J. Skeletal impairment in Pierson syndrome: Is there a role for lamininβ2 in bone physiology? Bone 2018; 106:187-193. [PMID: 29051055 DOI: 10.1016/j.bone.2017.10.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/25/2017] [Revised: 10/10/2017] [Accepted: 10/12/2017] [Indexed: 01/15/2023]
Abstract
INTRODUCTION Pierson syndrome is caused by a mutation of LAMB2, encoding for laminin β2. Clinical phenotype is variable but usually associates congenital nephrotic syndrome (CNS) and ocular abnormalities. Neuromuscular impairment has also been described. METHODS We report on a 15-year old girl, suffering from Pierson Syndrome, who developed severe bone deformations during puberty. This patient initially displayed CNS and microcoria, leading to the clinical diagnosis of Pierson syndrome. Genetic analysis revealed a truncating mutation and a splice site mutation of LAMB2. The patient received a renal transplantation (R-Tx) at the age of 3. After R-Tx, renal evolution was simple, the patient receiving low-dose corticosteroids, tacrolimus and mycophenolate mofetil. At the age of 12, bone deformations progressively appeared. At the time of bone impairment, renal function was subnormal (glomerular filtration rate using iohexol clearance 50mL/min per 1.73m2), and parameters of calcium/phosphate metabolism were normal (calcium 2.45mmol/L, phosphorus 1.30mmol/L, PTH 81ng/L, ALP 334U/L, 25OH-D 73nmol/L). Radiographs showed major deformations such as scoliosis, genu varum and diffuse epiphyseal abnormalities. A high resolution scanner (HR-pQCT) was performed, demonstrating a bone of "normal low" quantity and quality; major radial and cubital deformations were observed. Stainings of laminin β2 were performed on bone and renal samples from the patient and healthy controls: as expected, laminin β2 was expressed in the control kidney but not in the patient's renal tissue, and a similar pattern was observed in bone. CONCLUSION This is the first case of skeletal impairment ever described in Pierson syndrome. Integrin α3β1, receptor for laminin β2, are found in podocytes and osteoblasts, and the observation of both the presence of laminin β2 staining in healthy bone and its absence in the patient's bone raises the question of a potential role of laminin β2 in bone physiology.
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Affiliation(s)
- Camille Beaufils
- Centre de Référence des Maladies Rénales Rares, Hôpital Femme Mère Enfant, Hospices, Civils de Lyon, 69677 Bron, France.
| | - Delphine Farlay
- INSERM, UMR 1033, Université Claude Bernard Lyon 1, Lyon, France
| | | | - Alice Fassier
- Service de Chirurgie Orthopédique Pédiatrique, Hôpital Femme Mère Enfant, Hospices Civils de Lyon, Bron, France
| | - Martin Zenker
- Institute of Human Genetics, University Hospital Magdeburg, Germany
| | - Caroline Freychet
- Centre de Référence des Maladies Rénales Rares, Hôpital Femme Mère Enfant, Hospices, Civils de Lyon, 69677 Bron, France
| | - Edith Bonnelye
- INSERM, UMR 1033, Université Claude Bernard Lyon 1, Lyon, France
| | - Aurélia Bertholet-Thomas
- Centre de Référence des Maladies Rénales Rares, Hôpital Femme Mère Enfant, Hospices, Civils de Lyon, 69677 Bron, France
| | - Bruno Ranchin
- Centre de Référence des Maladies Rénales Rares, Hôpital Femme Mère Enfant, Hospices, Civils de Lyon, 69677 Bron, France
| | - Justine Bacchetta
- Centre de Référence des Maladies Rénales Rares, Hôpital Femme Mère Enfant, Hospices, Civils de Lyon, 69677 Bron, France; INSERM, UMR 1033, Université Claude Bernard Lyon 1, Lyon, France; Service de Chirurgie Orthopédique Pédiatrique, Hôpital Femme Mère Enfant, Hospices Civils de Lyon, Bron, France; Institute of Human Genetics, University Hospital Magdeburg, Germany; Faculté de Médecine Lyon Est, Université de Lyon, France, Lyon.
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16
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Oh SH, Kim JW, Kim Y, Lee MN, Kook MS, Choi EY, Im SY, Koh JT. The extracellular matrix protein Edil3 stimulates osteoblast differentiation through the integrin α5β1/ERK/Runx2 pathway. PLoS One 2017; 12:e0188749. [PMID: 29182679 PMCID: PMC5705136 DOI: 10.1371/journal.pone.0188749] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Accepted: 11/12/2017] [Indexed: 02/07/2023] Open
Abstract
Epidermal growth factor-like repeats and discoidin I-like domain 3 (Edil3) is an extracellular matrix protein containing an Arg-Gly-Asp (RGD) motif that binds integrin. Recently, Edil3 has been implicated in various biological processes, including angiogenesis and cellular differentiation. It can inhibit inflammatory bone destruction. The objective of this study was to explore the role of Edil3 in osteoblast differentiation and its underlying molecular mechanisms. In wild-type mice, high expression levels of Edil3 mRNA were observed in isolated calvaria and tibia/femur bones. Immunohistochemical analysis showed that Edil3 protein was localized along periosteum and calcified regions surrounding bone tissues. When murine calvaria-derived MC3T3-E1 cells were cultured in osteogenic medium containing 50 μg/ml ascorbic acid and 5 mM β-glycerophosphate, Edil3 mRNA and protein expression levels were increased. Treatment with Edil3 protein in growth media increased expression levels of alkaline phosphatase and osteocalcin gene and phosphorylation level of extracellular signal-regulated kinase (ERK). Edil3 treatment with osteogenic medium induced mineralization. Treatment with a neutralizing antibody against α5β1 and MEK inhibitor U0126 inhibited Edil3-enhanced osteogenic marker gene expression and mineral deposition. Edil3 increased protein expression levels of transcription factor runt-related transcription factor2 (Runx2). Edil3-induced Runx2 protein expression was suppressed by pretreatment with U0126. Taken together, these results suggest that Edil3 may stimulate osteoblast differentiation and matrix mineralization by increasing expression of Runx2 through α5β1 integrin /ERK pathway.
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Affiliation(s)
- Sin-Hye Oh
- Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea
- Department of Biological Sciences, College of Natural Sciences, Chonnam National University, Gwangju, Republic of Korea
| | - Jung-Woo Kim
- Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea
| | - Yuri Kim
- Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea
| | - Mi Nam Lee
- Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea
| | - Min-Suk Kook
- Department of Oral and Maxillofacial Surgery, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea
| | - Eun Young Choi
- Department of Biomedical Sciences, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Suhn-Young Im
- Department of Biological Sciences, College of Natural Sciences, Chonnam National University, Gwangju, Republic of Korea
| | - Jeong-Tae Koh
- Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju, Republic of Korea
- * E-mail:
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17
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Zhang M, Wang J, Deng C, Jiang MH, Feng X, Xia K, Li W, Lai X, Xiao H, Ge RS, Gao Y, Xiang AP. Transplanted human p75-positive stem Leydig cells replace disrupted Leydig cells for testosterone production. Cell Death Dis 2017; 8:e3123. [PMID: 29022899 PMCID: PMC5680910 DOI: 10.1038/cddis.2017.531] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Revised: 09/07/2017] [Accepted: 09/11/2017] [Indexed: 11/09/2022]
Abstract
Previous studies have demonstrated that rodent stem Leydig cell (SLC) transplantation can partially restore testosterone production in Leydig cell (LC)-disrupted or senescent animal models, which provides a promising approach for the treatment of hypogonadism. Here, we isolated human SLCs prospectively and explored the potential therapeutic benefits of human SLC transplantation for hypogonadism treatment. In adult human testes, p75 neurotrophin receptor positive (p75+) cells expressed the known SLC marker nestin, but not the LC lineage marker hydroxysteroid dehydrogenase-3β (HSD3β). The p75+ cells which were sorted by flow cytometry from human adult testes could expand in vitro and exhibited clonogenic self-renewal capacity. The p75+ cells had multi-lineage differentiation potential into multiple mesodermal cell lineages and testosterone-producing LCs in vitro. After transplantation into the testes of ethane dimethane sulfonate (EDS)-treated LC-disrupted rat models, the p75+ cells differentiated into LCs in vivo and secreted testosterone in a physiological pattern. Moreover, p75+ cell transplantation accelerated the recovery of serum testosterone levels, spermatogenesis and reproductive organ weights. Taken together, we reported a method for the identification and isolation of human SLCs on the basis of p75 expression, and demonstrated that transplanted human p75+ SLCs could replace disrupted LCs for testosterone production. These findings provide the groundwork for further clinical application of human SLCs for hypogonadism.
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Affiliation(s)
- Min Zhang
- Department of Andrology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China.,Center for Stem Cell Biology and Tissue Engineering, Key Laboratory for Stem Cells and Tissue Engineering, Ministry of Education, Sun Yat-sen University, Guangzhou, China
| | - Jiancheng Wang
- Center for Stem Cell Biology and Tissue Engineering, Key Laboratory for Stem Cells and Tissue Engineering, Ministry of Education, Sun Yat-sen University, Guangzhou, China
| | - Chunhua Deng
- Department of Andrology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China.,Center for Stem Cell Biology and Tissue Engineering, Key Laboratory for Stem Cells and Tissue Engineering, Ministry of Education, Sun Yat-sen University, Guangzhou, China.,Guangdong Provincial Key laboratory of Orthopedics and Traumatology, Guangzhou, China
| | - Mei Hua Jiang
- Center for Stem Cell Biology and Tissue Engineering, Key Laboratory for Stem Cells and Tissue Engineering, Ministry of Education, Sun Yat-sen University, Guangzhou, China.,Department of Anatomy and Neurobiology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
| | - Xin Feng
- Department of Andrology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Kai Xia
- Department of Andrology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Weiqiang Li
- Center for Stem Cell Biology and Tissue Engineering, Key Laboratory for Stem Cells and Tissue Engineering, Ministry of Education, Sun Yat-sen University, Guangzhou, China.,Department of Biochemistry, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
| | - Xingqiang Lai
- Center for Stem Cell Biology and Tissue Engineering, Key Laboratory for Stem Cells and Tissue Engineering, Ministry of Education, Sun Yat-sen University, Guangzhou, China.,Department of Biochemistry, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
| | - Haipeng Xiao
- Department of Endocrinology, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
| | - Ren-Shan Ge
- The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Yong Gao
- Reproductive Medicine Center, The Key Laboratory for Reproductive Medicine of Guangdong Province, The First Affiliated Hospital of Sun Yat-sen University, Wenzhou, Guangzhou, China
| | - Andy Peng Xiang
- Center for Stem Cell Biology and Tissue Engineering, Key Laboratory for Stem Cells and Tissue Engineering, Ministry of Education, Sun Yat-sen University, Guangzhou, China.,Department of Biochemistry, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China.,Key Laboratory of Protein Modification and Degradation, School of Basic Medical Sciences, Affiliated Cancer Hospital and Institute of Guangzhou Medical University, Guangzhou, China
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18
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Boyan BD, Cheng A, Olivares-Navarrete R, Schwartz Z. Implant Surface Design Regulates Mesenchymal Stem Cell Differentiation and Maturation. Adv Dent Res 2017; 28:10-7. [PMID: 26927483 DOI: 10.1177/0022034515624444] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Changes in dental implant materials, structural design, and surface properties can all affect biological response. While bulk properties are important for mechanical stability of the implant, surface design ultimately contributes to osseointegration. This article reviews the surface parameters of dental implant materials that contribute to improved cell response and osseointegration. In particular, we focus on how surface design affects mesenchymal cell response and differentiation into the osteoblast lineage. Surface roughness has been largely studied at the microscale, but recent studies have highlighted the importance of hierarchical micron/submicron/nanosurface roughness, as well as surface roughness in combination with surface wettability. Integrins are transmembrane receptors that recognize changes in the surface and mediate downstream signaling pathways. Specifically, the noncanonical Wnt5a pathway has been implicated in osteoblastic differentiation of cells on titanium implant surfaces. However, much remains to be elucidated. Only recently have studies been conducted on the differences in biological response to implants based on sex, age, and clinical factors; these all point toward differences that advocate for patient-specific implant design. Finally, challenges in implant surface characterization must be addressed to optimize and compare data across studies. An understanding of both the science and the biology of the materials is crucial for developing novel dental implant materials and surface modifications for improved osseointegration.
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Affiliation(s)
- B D Boyan
- Department of Biomedical Engineering, Virginia Commonwealth University, Richmond, Virginia, USA Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA, USA
| | - A Cheng
- Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA, USA Department of Biomedical Engineering, Peking University, Beijing, China
| | - R Olivares-Navarrete
- Department of Biomedical Engineering, Virginia Commonwealth University, Richmond, Virginia, USA
| | - Z Schwartz
- Department of Biomedical Engineering, Virginia Commonwealth University, Richmond, Virginia, USA University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
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19
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Lin TH, Yang RS, Tu HJ, Liou HC, Lin YM, Chuang WJ, Fu WM. Inhibition of osteoporosis by the αvβ3 integrin antagonist of rhodostomin variants. Eur J Pharmacol 2017; 804:94-101. [DOI: 10.1016/j.ejphar.2017.03.019] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2016] [Revised: 03/08/2017] [Accepted: 03/13/2017] [Indexed: 10/20/2022]
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20
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Sens C, Huck K, Pettera S, Uebel S, Wabnitz G, Moser M, Nakchbandi IA. Fibronectins containing extradomain A or B enhance osteoblast differentiation via distinct integrins. J Biol Chem 2017; 292:7745-7760. [PMID: 28325836 DOI: 10.1074/jbc.m116.739987] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2016] [Revised: 03/10/2017] [Indexed: 12/16/2022] Open
Abstract
Fibronectin is a multidomain protein secreted by various cell types. It forms a network of fibers within the extracellular matrix and impacts intracellular processes by binding to various molecules, primarily integrin receptors on the cells. Both the presence of several isoforms and the ability of the various domains and isoforms to bind to a variety of integrins result in a wide range of effects. In vivo findings suggest that fibronectin isoforms produced by the osteoblasts enhance their differentiation. Here we report that the isoform characterized by the presence of extradomain A activates α4β1 integrin and augments osteoblast differentiation. In addition, the isoform containing extradomain B enhances the binding of fibronectin through the RGD sequence to β3-containing integrin, resulting in increased mineralization by and differentiation of osteoblasts. Our study thus reveals novel functions for two fibronectin isoforms and the mediating receptors in osteoblast differentiation.
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Affiliation(s)
- Carla Sens
- From the Max-Planck Institute of Biochemistry, 82152 Martinsried and.,the Institute of Immunology, University of Heidelberg, 69120 Heidelberg, Germany
| | - Katrin Huck
- From the Max-Planck Institute of Biochemistry, 82152 Martinsried and.,the Institute of Immunology, University of Heidelberg, 69120 Heidelberg, Germany
| | - Stefan Pettera
- From the Max-Planck Institute of Biochemistry, 82152 Martinsried and
| | - Stephan Uebel
- From the Max-Planck Institute of Biochemistry, 82152 Martinsried and
| | - Guido Wabnitz
- the Institute of Immunology, University of Heidelberg, 69120 Heidelberg, Germany
| | - Markus Moser
- From the Max-Planck Institute of Biochemistry, 82152 Martinsried and
| | - Inaam A Nakchbandi
- From the Max-Planck Institute of Biochemistry, 82152 Martinsried and .,the Institute of Immunology, University of Heidelberg, 69120 Heidelberg, Germany
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21
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Zaveri TD, Dolgova NV, Lewis JS, Hamaker K, Clare-Salzler MJ, Keselowsky BG. Macrophage integrins modulate response to ultra-high molecular weight polyethylene particles and direct particle-induced osteolysis. Biomaterials 2017; 115:128-140. [PMID: 27889664 PMCID: PMC5431751 DOI: 10.1016/j.biomaterials.2016.10.038] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Revised: 10/26/2016] [Accepted: 10/26/2016] [Indexed: 12/25/2022]
Abstract
Aseptic loosening due to peri-prosthetic osteolysis is one of the primary causes for failure of artificial joint replacements. Implant-derived wear particles, often ultra-high molecular weight polyethylene (UHMWPE) microparticles, initiate an inflammatory cascade upon phagocytosis by macrophages, which leads to osteoclast recruitment and activation, ultimately resulting in osteolysis. Investigation into integrin receptors, involved in cellular interactions with biomaterial-adsorbed adhesive proteins, is of interest to understand and modulate inflammatory processes. In this work, we investigate the role of macrophage integrins Mac-1 and RGD-binding integrins in response to UHMWPE wear particles. Using integrin knockout mice as well as integrin blocking techniques, reduction in macrophage phagocytosis and inflammatory cytokine secretion is demonstrated when these receptors are either absent or blocked. Along this line, various opsonizing proteins are shown to differentially modulate microparticle uptake and macrophage secretion of inflammatory cytokines. Furthermore, using a calvarial osteolysis model it is demonstrated that both Mac-1 integrin and RGD-binding integrins modulate the particle induced osteolysis response to UHMWPE microparticles, with a 40% decrease in the area of osteolysis by the absence or blocking of these integrins, in vivo. Altogether, these findings indicate Mac-1 and RGD-binding integrins are involved in macrophage-directed inflammatory responses to UHMWPE and may serve as therapeutic targets to mitigate wear particle induced peri-prosthetic osteolysis for improved performance of implanted joints.
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Affiliation(s)
- Toral D Zaveri
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, FL 32611, USA; Department of Food Science, The Pennsylvania State University, University Park, PA 16802, USA
| | - Natalia V Dolgova
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, FL 32611, USA
| | - Jamal S Lewis
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, FL 32611, USA; Department of Biomedical Engineering, University of California, Davis, Davis, CA 95618, USA
| | - Kiri Hamaker
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, FL 32611, USA
| | - Michael J Clare-Salzler
- Department of Pathology, Immunology and Laboratory Medicine, University of Florida, Gainesville, FL 32611, USA
| | - Benjamin G Keselowsky
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, FL 32611, USA.
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22
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Rational design of a protein that binds integrin αvβ3 outside the ligand binding site. Nat Commun 2016; 7:11675. [PMID: 27241473 PMCID: PMC4895024 DOI: 10.1038/ncomms11675] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2015] [Accepted: 04/19/2016] [Indexed: 12/28/2022] Open
Abstract
Integrin αvβ3 expression is altered in various diseases and has been proposed as a drug target. Here we use a rational design approach to develop a therapeutic protein, which we call ProAgio, that binds to integrin αvβ3 outside the classical ligand-binding site. We show ProAgio induces apoptosis of integrin αvβ3-expressing cells by recruiting and activating caspase 8 to the cytoplasmic domain of integrin αvβ3. ProAgio also has anti-angiogenic activity and strongly inhibits growth of tumour xenografts, but does not affect the established vasculature. Toxicity analyses demonstrate that ProAgio is not toxic to mice. Our study reports a new integrin-targeting agent with a unique mechanism of action, and provides a template for the development of integrin-targeting therapeutics. Integrins are transmembrane proteins that have important roles in cell adhesion and signalling. Here the authors design a therapeutic protein that binds integrin αvβ3, has anti-angiogenic activity, and reduces tumour growth in xenograft models, while being seemingly well tolerated.
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23
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Gao B, Huang Q, Jie Q, Lu WG, Wang L, Li XJ, Sun Z, Hu YQ, Chen L, Liu BH, Liu J, Yang L, Luo ZJ. GPR120: A bi-potential mediator to modulate the osteogenic and adipogenic differentiation of BMMSCs. Sci Rep 2015; 5:14080. [PMID: 26365922 PMCID: PMC4568495 DOI: 10.1038/srep14080] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Accepted: 08/18/2015] [Indexed: 12/14/2022] Open
Abstract
Free fatty acids display diverse effects as signalling molecules through GPCRs in addition to their involvement in cellular metabolism. GPR120, a G protein-coupled receptor for long-chain unsaturated fatty acids, has been reported to mediate adipogenesis in lipid metabolism. However, whether GPR120 also mediates osteogenesis and regulates BMMSCs remain unclear. In this study, we showed that GPR120 targeted the bi-potential differentiation of BMMSCs in a ligand dose-dependent manner. High concentrations of TUG-891 (a highly selective agonist of GPR120) promoted osteogenesis via the Ras-ERK1/2 cascade, while low concentrations elevated P38 and increased adipogenesis. The fine molecular regulation of GPR120 was implemented by up-regulating different integrin subunits (α1, α2 and β1; α5 and β3). The administration of high doses of TUG-891 rescued oestrogen-deficient bone loss in vivo, further supporting an essential role of GPR120 in bone metabolism. Our findings, for the first time, showed that GPR120-mediated cellular signalling determines the bi-potential differentiation of BMMSCs in a dose-dependent manner. Additionally, the induction of different integrin subunits was involved in the cytoplasmic regulation of a seesaw-like balance between ERK and p38 phosphorylation. These findings provide new hope for developing novel remedies to treat osteoporosis by adjusting the GPR120-mediated differentiation balance of BMMSCs.
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Affiliation(s)
- Bo Gao
- Institute of Orthopedic Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, People's Republic of China
| | - Qiang Huang
- Lanzhou General Hospital of Lanzhou Military Command, Lanzhou Gansu, 730050, People's Republic of China
| | - Qiang Jie
- Institute of Orthopedic Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, People's Republic of China
| | - Wei-Guang Lu
- Institute of Orthopedic Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, People's Republic of China
| | - Long Wang
- Institute of Orthopedic Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, People's Republic of China
| | - Xiao-Jie Li
- Institute of Orthopedic Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, People's Republic of China
| | - Zhen Sun
- Institute of Orthopedic Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, People's Republic of China
| | - Ya-Qian Hu
- Institute of Orthopedic Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, People's Republic of China
| | - Li Chen
- KMEB, Molecular Endocrinology, Campusvej 55, DK-5230 Odense M, Denmark
| | - Bao-Hua Liu
- Health Science Center, Shenzhen University, 3688 Nanhai Ave, Shenzhen 518060, People's Republic of China
| | - Jian Liu
- Institute of Orthopedic Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, People's Republic of China
| | - Liu Yang
- Institute of Orthopedic Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, People's Republic of China
| | - Zhuo-Jing Luo
- Institute of Orthopedic Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, People's Republic of China
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24
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Salamanna F, Maglio M, Giavaresi G, Pagani S, Giardino R, Fini M. In vitro method for the screening and monitoring of estrogen-deficiency osteoporosis by targeting peripheral circulating monocytes. AGE (DORDRECHT, NETHERLANDS) 2015; 37:9819. [PMID: 26250906 PMCID: PMC5005821 DOI: 10.1007/s11357-015-9819-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2015] [Accepted: 07/20/2015] [Indexed: 06/04/2023]
Abstract
Bone loss occurs insidiously and initially asymptomatically; therefore, osteoporosis is frequently diagnosed only after the first clinical fracture. The aim of this study was to test the hypothesis is that by simply observing the behavior of cultured peripheral monocytes, it might be possible to diagnose altered bone remodeling and, therefore, limit the complications associated with osteoporosis, especially fractures. Monocytes isolated as mononuclear precursors from healthy and ovariectomized rats were cultured both in basal and differentiation medium for up to 3 weeks. Viability and differentiation capability towards the osteoclastic phenotype was checked by light microscopy at early times, whereas differentiation state and synthetic activity (tartrate-resistant acid phosphatase (TRAP) staining; phalloidin, fluorescin isothiocynate (FITC) staining, cathepsin K, metalloproteinase 7 and 9, MMP-7 and MMP-9) were measured at 1, 2, and 3 weeks. Compared to their controls, monocytes isolated from ovariectomized rats proliferate and lean toward the osteoclastic phenotype in the absence of differentiating factors. In both culture conditions, osteoclasts from ovariectomized rats showed significantly higher productions of cathepsin K, MMP-7, and MMP-9 than those of cells isolated from healthy rats, steadily over time. These results obtained in an animal osteoporotic model, if confirmed by clinical studies, open up the possibility to assess the presence of an alteration in bone remodeling with a simple in vitro diagnostic test requiring a small blood sample and less than 48 h. This might allow to early select patients with a spontaneous viability and differentiation of monocytes to osteoclasts for further diagnostic techniques.
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Affiliation(s)
- Francesca Salamanna
- Laboratory of Biocompatibility, Technological Innovations and Advanced Therapies, Rizzoli Research Innovation Technology, Via di Barbiano, 1/10, 40136, Bologna, Italy,
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25
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Voisin M, McNamara LM. Differential β3 and β1 Integrin Expression in Bone Marrow and Cortical Bone of Estrogen Deficient Rats. Anat Rec (Hoboken) 2015; 298:1548-59. [PMID: 25974241 DOI: 10.1002/ar.23173] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2014] [Revised: 02/23/2015] [Accepted: 04/01/2015] [Indexed: 12/20/2022]
Abstract
Integrin-based (β3 ) attachments to the extracellular matrix (ECM) on osteocyte cell processes have recently been proposed to play an important role in facilitating osteocyte mechanosensation. However, it is not yet known whether integrin expression is altered in the mechanoregulatory osteocytes during osteoporosis. The objective of this study was to test the hypothesis that the expression of integrin-based mechanosensory complexes (β1 and β3 integrins) is altered as a direct response to estrogen deficiency, in an estrogen deficient animal model of osteoporosis. Four weeks post-operatively, immunohistochemistry was used to detect for β1 and β3 integrin subunits in bone tissue and marrow of ovariectomized (OVX; N = 4) and SHAM (N = 4) operated animals. A tartrate resistant acid phosphatase (TRAP) control stain was performed to quantify the presence of osteoclasts in the bone marrow and bone surfaces. Image analysis was performed to quantify expression patterns in different biological compartments, that is, bone marrow, endosteum, and cortical bone. Our results showed that β1 integrins were ubiquitously expressed throughout the bone and marrow, for both OVX and SHAM groups. β3 integrin subunit expression was lower in bone cells from osteoporotic animals compared to controls, whereas β3 expression in marrow cells did not differ significantly between groups. At the endosteum no difference was observed in β3 integrin subunit expression. As expected, the number of osteoclasts was higher in the OVX group validating an imbalance in bone remodeling. We propose that a reduction in β3 integrin expression in osteocytes might impair mechanosensation by bone cells during estrogen deficiency.
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Affiliation(s)
- Muriel Voisin
- Biomechanics Research Centre (BMEC), Biomedical Engineering, College of Engineering and Informatics, National University of Ireland Galway, Ireland
| | - Laoise M McNamara
- Biomechanics Research Centre (BMEC), Biomedical Engineering, College of Engineering and Informatics, National University of Ireland Galway, Ireland
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26
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Itzstein C, Coxon FP, Rogers MJ. The regulation of osteoclast function and bone resorption by small GTPases. Small GTPases 2014; 2:117-130. [PMID: 21776413 DOI: 10.4161/sgtp.2.3.16453] [Citation(s) in RCA: 106] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2011] [Revised: 04/22/2011] [Accepted: 05/10/2011] [Indexed: 01/11/2023] Open
Abstract
Osteoclasts are multinucleated cells that are responsible for resorption of bone, and increased activity of these cells is associated with several common bone diseases, including postmenopausal osteoporosis. Upon adhesion to bone, osteoclasts become polarized and reorganise their cytoskeleton and membrane to form unique domains including the sealing zone (SZ), which is a dense ring of F-actin-rich podosomes delimiting the ruffled border (RB), where protons and proteases are secreted to demineralise and degrade the bone matrix, respectively. These processes are dependent on the activity of small GTPases. Rho GTPases are well known to control the organization of F-actin and adhesion structures of different cell types, affecting subsequently their migration. In osteoclasts, RhoA, Rac, Cdc42, RhoU and also Arf6 regulate podosome assembly and their organization into the SZ. By contrast, the formation of the RB involves vesicular trafficking pathways that are regulated by the Rab family of GTPases, in particular lysosomal Rab7. Finally, osteoclast survival is dependent on the activity of Ras GTPases. The correct function of almost all these GTPases is absolutely dependent on post-translational prenylation, which enables them to localize to specific target membranes. Bisphosphonate drugs, which are widely used in the treatment of bone diseases such as osteoporosis, act by preventing the prenylation of small GTPases, resulting in the loss of the SZ and RB and therefore inhibition of osteoclast activity, as well as inducing osteoclast apoptosis. In this review we summarize current understanding of the role of specific prenylated small GTPases in osteoclast polarization, function and survival.
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Affiliation(s)
- Cecile Itzstein
- Musculoskeletal Research Programme; Institute of Medical Sciences; University of Aberdeen; Aberdeen, Scotland UK
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27
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Moussa FM, Hisijara IA, Sondag GR, Scott EM, Frara N, Abdelmagid SM, Safadi FF. Osteoactivin Promotes Osteoblast Adhesion Through HSPG and αvβ1 Integrin. J Cell Biochem 2014; 115:1243-53. [DOI: 10.1002/jcb.24760] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2014] [Accepted: 01/07/2014] [Indexed: 01/31/2023]
Affiliation(s)
- Fouad M. Moussa
- Department of Anatomy and Neurobiology; Northeast Ohio Medical University (NEOMED); Rootstown Ohio
- School of Biomedical Sciences; Kent State University; Kent Ohio
| | | | - Gregory R. Sondag
- Department of Anatomy and Neurobiology; Northeast Ohio Medical University (NEOMED); Rootstown Ohio
- School of Biomedical Sciences; Kent State University; Kent Ohio
| | - Ethan M. Scott
- Department of Anatomy and Neurobiology; Northeast Ohio Medical University (NEOMED); Rootstown Ohio
| | - Nagat Frara
- Department of Anatomy and Cell Biology; Temple University; Philadelphia Pennsylvania
| | - Samir M. Abdelmagid
- Department of Anatomy and Neurobiology; Northeast Ohio Medical University (NEOMED); Rootstown Ohio
| | - Fayez F. Safadi
- Department of Anatomy and Neurobiology; Northeast Ohio Medical University (NEOMED); Rootstown Ohio
- School of Biomedical Sciences; Kent State University; Kent Ohio
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28
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Ho Y, Kok SH, Wang JS, Lin LD. Translucent titanium coating altered the composition of focal adhesions and promoted migration of osteoblast-like MG-63 cells on glass. J Biomed Mater Res A 2013; 102:1187-201. [DOI: 10.1002/jbm.a.34760] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2013] [Revised: 04/02/2013] [Accepted: 04/17/2013] [Indexed: 11/11/2022]
Affiliation(s)
- Yi Ho
- Graduate Institute of Clinical Dentistry, School of Dentistry; National Taiwan University; Taipei Taiwan
| | - Sang-Heng Kok
- Department of Dentistry, School of Dentistry; National Taiwan University; Taipei Taiwan
- Department of Dentistry; National Taiwan University Hospital; Taipei Taiwan
| | - Juo-Song Wang
- Department of Dentistry, School of Dentistry; National Taiwan University; Taipei Taiwan
- Department of Dentistry; National Taiwan University Hospital; Taipei Taiwan
| | - Li-Deh Lin
- Graduate Institute of Clinical Dentistry, School of Dentistry; National Taiwan University; Taipei Taiwan
- Department of Dentistry, School of Dentistry; National Taiwan University; Taipei Taiwan
- Department of Dentistry; National Taiwan University Hospital; Taipei Taiwan
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29
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Pathobiology and management of prostate cancer-induced bone pain: recent insights and future treatments. Inflammopharmacology 2013; 21:339-63. [PMID: 23918298 PMCID: PMC3779011 DOI: 10.1007/s10787-013-0183-7] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2013] [Accepted: 07/23/2013] [Indexed: 12/27/2022]
Abstract
Prostate cancer (PCa) has a high propensity for metastasis to bone. Despite the availability of multiple treatment options for relief of PCa-induced bone pain (PCIBP), satisfactory relief of intractable pain in patients with advanced bony metastases is challenging for the clinicians because currently available analgesic drugs are often limited by poor efficacy and/or dose-limiting side effects. Rodent models developed in the past decade show that the pathobiology of PCIBP comprises elements of inflammatory, neuropathic and ischemic pain arising from ectopic sprouting and sensitization of sensory nerve fibres within PCa-invaded bones. In addition, at the cellular level, PCIBP is underpinned by dynamic cross talk between metastatic PCa cells, cellular components of the bone matrix, factors associated with the bone microenvironment as well as peripheral components of the somatosensory system. These insights are aligned with the clinical management of PCIBP involving use of a multimodal treatment approach comprising analgesic agents (opioids, NSAIDs), radiotherapy, radioisotopes, cancer chemotherapy agents and bisphosphonates. However, a major drawback of most rodent models of PCIBP is their short-term applicability due to ethical concerns. Thus, it has been difficult to gain insight into the mal(adaptive) neuroplastic changes occurring at multiple levels of the somatosensory system that likely contribute to intractable pain at the advanced stages of metastatic disease. Specifically, the functional responsiveness of noxious circuitry as well as the neurochemical signature of a broad array of pro-hyperalgesic mediators in the dorsal root ganglia and spinal cord of rodent models of PCIBP is relatively poorly characterized. Hence, recent work from our laboratory to develop a protocol for an optimized rat model of PCIBP will enable these knowledge gaps to be addressed as well as identification of novel targets for drug discovery programs aimed at producing new analgesics for the improved relief of intractable PCIBP.
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30
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Faienza MF, Ventura A, Marzano F, Cavallo L. Postmenopausal osteoporosis: the role of immune system cells. Clin Dev Immunol 2013; 2013:575936. [PMID: 23762093 PMCID: PMC3677008 DOI: 10.1155/2013/575936] [Citation(s) in RCA: 90] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2013] [Accepted: 05/10/2013] [Indexed: 01/09/2023]
Abstract
In the last years, new evidences of the relationship between immune system and bone have been accumulated both in animal models and in humans affected by bone disease, such as rheumatoid arthritis, bone metastasis, periodontitis, and osteoporosis. Osteoporosis is characterized by low bone mass and microarchitectural deterioration of bone tissue with a subsequent increase in bone fragility and susceptibility to fractures. The combined effects of estrogen deprivation and raising of FSH production occurring in menopause cause a marked stimulation of bone resorption and a rapid bone loss which is central for the onset of postmenopausal osteoporosis. This review focuses on the role of immune system in postmenopausal osteoporosis and on therapeutic strategies targeting osteoimmunology pathways.
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Affiliation(s)
- Maria Felicia Faienza
- Department of Biomedical Sciences and Human Oncology, University of Bari Aldo Moro, 70124 Bari, Italy.
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31
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Fluid flow in the osteocyte mechanical environment: a fluid–structure interaction approach. Biomech Model Mechanobiol 2013; 13:85-97. [DOI: 10.1007/s10237-013-0487-y] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2012] [Accepted: 03/26/2013] [Indexed: 10/27/2022]
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Lomas AJ, Webb WR, Han J, Chen GQ, Sun X, Zhang Z, El Haj AJ, Forsyth NR. Poly (3-hydroxybutyrate-co-3-hydroxyhexanoate)/collagen hybrid scaffolds for tissue engineering applications. Tissue Eng Part C Methods 2013; 19:577-85. [PMID: 23281705 DOI: 10.1089/ten.tec.2012.0457] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
The benefits associated with polyhydroxyalkanoates (PHA) in tissue engineering include high immunotolerance, low toxicity, and biodegradability. Poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx), a molecule from the PHA family of biopolymers, shares these features. In this study, the applicability of human embryonic stem cells (hESCs), spontaneously differentiated hESCs (SDhESCs), and mesenchymal stem cells (hMSCs) in conjunction with PHBHHx and collagen as a biocompatible replacement strategy for damaged tissues was exploited. Collagen gel contraction was monitored by seeding cells at controlled densities (0, 10(3), 10(4), and 10(5) cells/mL) and measuring length and diameter at regular time intervals thereafter when cultured in a complete medium. Cell viability was measured by trypan blue exclusion assay. Porous PHBHHx tube scaffolds were prepared using a dipping method followed by salt leaching. PHBHHx/collagen composites were generated via syringe injection of collagen/cell mixtures into sterile PHBHHx porous tubes. Reverse transcription polymerase chain reaction was used to determine the fate of cells within PHBHHx/collagen scaffolds with tendon, bone, cartilage, and fat-linked transcript expression being explored at days 0, 5 10, and 20. The capacity of PHBHHx/collagen scaffolds to support differentiation was explored using a medium specific for osteogenic, chondrogenic, and adipogenic lineage generation. Collagen gel tube contraction required initial seeding densities of ≥10(5) hMSCs or SDhESCs in 1.5 mg/mL collagen gel tubes. Gels with a collagen concentration of 3 mg/mL did not display contraction across the examined cell seeding densities. Cell viability was ∼50% for SDhESC and 90% for hMSCs at all cell densities tested in porous PHBHHx tube/3 mg/mL collagen hybrid scaffolds after 20 days in vitro culture. Undifferentiated hESCs did not contract collagen gel tubes and were unviable after 20 days culture. In the absence of additional stimuli, SOX9 was sporadically found, while RUNX2 was not present in both hMSC and SDhESC. Hybrid scaffolds were shown to promote retention of osteogenic, chondrogenic, and adipogenic differentiation by expression of RUNX2, SOX9, and PPARγ genes, respectively, following exposure to the appropriate induction medium. PHBHHx/collagen scaffolds have been successfully used to culture hMSC and SDhESC over an extended period supporting the potential of this scaffold combination in future tissue engineering applications.
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Affiliation(s)
- Alex J Lomas
- Institute for Science and Technology in Medicine, Keele University, Guy Hilton Research Centre, Stoke-on-Trent, United Kingdom
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33
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Weitzmann MN. The Role of Inflammatory Cytokines, the RANKL/OPG Axis, and the Immunoskeletal Interface in Physiological Bone Turnover and Osteoporosis. SCIENTIFICA 2013; 2013:125705. [PMID: 24278766 PMCID: PMC3820310 DOI: 10.1155/2013/125705] [Citation(s) in RCA: 108] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2012] [Accepted: 12/24/2012] [Indexed: 05/30/2023]
Abstract
Although it has long been recognized that inflammation, a consequence of immune-driven processes, significantly impacts bone turnover, the degree of centralization of skeletal and immune functions has begun to be dissected only recently. It is now recognized that formation of osteoclasts, the bone resorbing cells of the body, is centered on the key osteoclastogenic cytokine, receptor activator of NF- κ B ligand (RANKL). Although numerous inflammatory cytokines are now recognized to promote osteoclast formation and skeletal degradation, with just a few exceptions, RANKL is now considered to be the final downstream effector cytokine that drives osteoclastogenesis and regulates osteoclastic bone resorption. The biological activity of RANKL is moderated by its physiological decoy receptor, osteoprotegerin (OPG). New discoveries concerning the sources and regulation of RANKL and OPG in physiological bone turnover as well as under pathological (osteoporotic) conditions continue to be made, opening a window to the complex regulatory processes that control skeletal integrity and the depth of integration of the skeleton within the immune response. This paper will examine the interconnection between bone turnover and the immune system and the implications thereof for physiological and pathological bone turnover.
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Affiliation(s)
- M. Neale Weitzmann
- Atlanta Department of Veterans Affairs Medical Center, Decatur, GA 30033, USA
- Division of Endocrinology and Metabolism and Lipids, Department of Medicine, Emory University School of Medicine, 101 Woodruff Circle, 1305 WMRB, Atlanta, GA 30322, USA
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34
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Osseointegration—Molecular events at the bone–implant interface: A review. JOURNAL OF ORAL AND MAXILLOFACIAL SURGERY MEDICINE AND PATHOLOGY 2013. [DOI: 10.1016/j.ajoms.2012.01.008] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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35
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De Vito P, Balducci V, Leone S, Percario Z, Mangino G, Davis PJ, Davis FB, Affabris E, Luly P, Pedersen JZ, Incerpi S. Nongenomic effects of thyroid hormones on the immune system cells: New targets, old players. Steroids 2012; 77:988-95. [PMID: 22414628 DOI: 10.1016/j.steroids.2012.02.018] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/06/2011] [Revised: 02/06/2012] [Accepted: 02/23/2012] [Indexed: 11/30/2022]
Abstract
It is now widely accepted that thyroid hormones, l-thyroxine (T(4)) and 3,3',5-triiodo-l-thyronine (T(3)), act as modulators of the immune response. Immune functions such as chemotaxis, phagocytosis, generation of reactive oxygen species, and cytokine synthesis and release, are altered in hypo- and hyper-thyroid conditions, even though for many immune cells no clear correlation has been found between altered levels of T(3) or T(4) and effects on the immune responses. Integrins are extracellular matrix proteins that are important modulators of many cellular responses, and the integrin αvβ3 has been identified as a cell surface receptor for thyroid hormones. Rapid signaling via this plasma membrane binding site appears to be responsible for many nongenomic effects of thyroid hormones, independent of the classic nuclear receptors. Through the integrin αvβ3 receptor the hormone can activate both the ERK1/2 and phosphatidylinositol 3-kinase pathways, with downstream effects including intracellular protein trafficking, angiogenesis and tumor cell proliferation. It has recently become clear that an important downstream target of the thyroid hormone nongenomic pathway may be the mammalian target of rapamycin, mTOR. New results demonstrate the capability of T(3) or T(4) to induce in the short time range important responses related to the immune function, such as reactive oxygen species production and cell migration in THP-1 monocytes. Thus thyroid hormones seem to be able to modulate the immune system by a combination of rapid nongenomic responses interacting with the classical nuclear response.
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Affiliation(s)
- Paolo De Vito
- Dept. of Biology, University of Rome Tor Vergata, 00133 Rome, Italy.
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Xu JK, Chen HJ, Li XD, Huang ZL, Xu H, Yang HL, Hu J. Optimal intensity shock wave promotes the adhesion and migration of rat osteoblasts via integrin β1-mediated expression of phosphorylated focal adhesion kinase. J Biol Chem 2012; 287:26200-12. [PMID: 22654119 PMCID: PMC3406705 DOI: 10.1074/jbc.m112.349811] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2012] [Revised: 05/15/2012] [Indexed: 02/05/2023] Open
Abstract
To search for factors promoting bone fracture repair, we investigated the effects of extracorporeal shock wave (ESW) on the adhesion, spreading, and migration of osteoblasts and its specific underlying cellular mechanisms. After a single period of stimulation by 10 kV (500 impulses) of shock wave (SW), the adhesion rate was increased as compared with the vehicle control. The data from both wound healing and transwell tests confirmed an acceleration in the migration of osteoblasts by SW treatment. RT-PCR, flow cytometry, and Western blotting showed that SW rapidly increased the surface expression of α5 and β1 subunit integrins, indicating that integrin β1 acted as an early signal for ESW-induced osteoblast adhesion and migration. It has also been found that a significant elevation occurred in the expression of phosphorylated β-catenin and focal adhesion kinase (FAK) at the site of tyrosine 397 in response to SW stimulation after the increasing expression of the integrin β1 molecule. When siRNAs of integrin α5 and β1 subunit were added, the level of FAK phosphorylation elevated by SW declined. Interestingly, the adhesion and migration of osteoblasts were decreased when these siRNA reagents as well as the ERK1/2 signaling pathway inhibitors, U0126 and PD98059, were present. Further studies demonstrated that U0126 could inhibit the downstream integrin-dependent signaling pathways, such as the FAK signaling pathway, whereas it had no influence on the synthesis of integrin β1 molecule. In conclusion, these data suggest that ESW promotes the adhesion and migration of osteoblasts via integrin β1-mediated expression of phosphorylated FAK at the Tyr-397 site; in addition, ERK1/2 are also important for osteoblast adhesion, spreading, migration, and integrin expression.
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Affiliation(s)
- Jian-kun Xu
- From the Department of Orthopedics, First Affiliated Hospital, Shantou University Medical College, 57 Changping Road, Shantou, Guangdong 515041, China
| | - Hong-jiang Chen
- From the Department of Orthopedics, First Affiliated Hospital, Shantou University Medical College, 57 Changping Road, Shantou, Guangdong 515041, China
| | - Xue-dong Li
- From the Department of Orthopedics, First Affiliated Hospital, Shantou University Medical College, 57 Changping Road, Shantou, Guangdong 515041, China
| | - Zhong-lian Huang
- From the Department of Orthopedics, First Affiliated Hospital, Shantou University Medical College, 57 Changping Road, Shantou, Guangdong 515041, China
| | - Huan Xu
- From the Department of Orthopedics, First Affiliated Hospital, Shantou University Medical College, 57 Changping Road, Shantou, Guangdong 515041, China
| | - Hai-long Yang
- From the Department of Orthopedics, First Affiliated Hospital, Shantou University Medical College, 57 Changping Road, Shantou, Guangdong 515041, China
| | - Jun Hu
- From the Department of Orthopedics, First Affiliated Hospital, Shantou University Medical College, 57 Changping Road, Shantou, Guangdong 515041, China
- To whom correspondence should be addressed. Tel.: 86-754-88905206; Fax: 86-754-88259850; E-mail:
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Yu HS, Noh WC, Park JW, Lee JM, Yang DJ, Park KB, Suh JY. Comparative study on the cellular activities of osteoblast-like cells and new bone formation of anorganic bone mineral coated with tetra-cell adhesion molecules and synthetic cell binding peptide. J Periodontal Implant Sci 2011; 41:293-301. [PMID: 22324007 PMCID: PMC3259238 DOI: 10.5051/jpis.2011.41.6.293] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2011] [Accepted: 10/22/2011] [Indexed: 11/08/2022] Open
Abstract
Purpose We have previously reported that tetra-cell adhesion molecule (T-CAM) markedly enhanced the differentiation of osteoblast-like cells grown on anorganic bone mineral (ABM). T-CAM comprises recombinant peptides containing the Arg-Gly-Asp (RGD) sequence in the tenth type III domain, Pro-His-Ser-Arg-Asn (PHSRN) sequence in the ninth type III domain of fibronectin (FN), and the Glu-Pro-Asp-Ilu-Met (EPDIM) and Tyr-His (YH) sequence in the fourth fas-1 domain of βig-h3. Therefore, the purpose of this study was to evaluate the cellular activity of osteoblast-like cells and the new bone formation on ABM coated with T-CAM, while comparing the results with those of synthetic cell binding peptide (PepGen P-15). Methods To analyze the cell viability, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was performed, andto analyze gene expression, northernblot was performed. Mineral nodule formations were evaluated using alizarin red stain. The new bone formations of each group were evaluated using histologic observation and histomorphometrc analysis. Results Expression of alkaline phosphatase mRNA was similar in all groups on days 10 and 20. The highest expression of osteopontin mRNA was observed in the group cultured with ABM/P-15, followed by those with ABM/T-CAM and ABM on days 20 and 30. Little difference was seen in the level of expression of collagen type I mRNA on the ABM, ABM/T-CAM, and ABM/P-15 cultured on day 20. There were similar growth and proliferation patterns for the ABM/T-CAM and ABM/P-15. The halo of red stain consistent with Ca2+ deposition was wider and denser around ABM/T-CAM and ABM/P-15 particles than around the ABM particles. The ABM/T-CAM group seemed to have bone forming bioactivity similar to that of ABM/P-15. A complete bony bridge was seen in two thirds of the defects in the ABM/T-CAM and ABM/P-15 groups. Conclusions ABM/T-CAM, which seemed to have bone forming bioactivity similar to ABM/P-15, was considered to serve as effective tissue-engineered bone graft material.
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Affiliation(s)
- Hyeon-Seok Yu
- Department of Periodontology, Kyungpook National University School of Dentistry, Daegu, Korea
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Idris SB, Bolstad AI, Ibrahim SO, Dånmark S, Finne-Wistrand A, Albertsson AC, Arvidson K, Mustafa K. Global gene expression profile of osteoblast-like cells grown on polyester copolymer scaffolds. Tissue Eng Part A 2011; 17:2817-31. [PMID: 21905880 DOI: 10.1089/ten.tea.2010.0660] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
One of the principal goals in tissue engineering is to produce scaffold materials that will guide cells to differentiate and regenerate functional replacement tissue at the site of injury. Poly(l-lactide-co-1,5-dioxepan-2-one) [Poly(LLA-co-DXO)], a potential scaffolding material for bone tissue engineering, has high hydrophilicity. Previous in vitro studies using human osteoblast-like cells (HOBs) demonstrated greater cytocompatibility and enhanced osteogenic differentiation when HOBs were seeded onto Poly(LLA-co-DXO) compared to Poly(l-lactide) [P(LLA)] scaffolds. The aim of the study was to identify the gene expression profiles of HOBs obtained from alveolar bone and grown on Poly(LLA-co-DXO) biodegradable polymer scaffolds compared to P(LLA) one. Illumina HumanWG-6 v3.0 Expression BeadChips were used for the gene expression analysis. Several genes were found as differentially expressed at 24 h and at 21 days. Expression of genes related to cell adhesion, cytoskeleton, antiapoptosis, proliferation, and bone mineralization was influenced by adding the monomer 1,5-dioxepan-2-one to the L-lactide. Genes related to three biological pathways involving Integrin, Notch, and Ras were found to be upregulated. For selected genes, results were confirmed by quantitative reverse transcriptase-polymerase chain reaction. Further, calcium content analysis revealed a significant enhancement of calcium deposition on both tested scaffolds. This observation was confirmed by Von Kossa and Alizarin Red S staining. Findings of this study are relevant to a better understanding of the molecular mechanisms underlying the behavior of HOBs in bone regenerative procedure.
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Affiliation(s)
- Shaza B Idris
- Department of Clinical Dentistry-Center for Clinical Dental Research, Faculty of Medicine and Dentistry, University of Bergen, Bergen, Norway.
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Abstract
Osteoclasts are cells essential for physiologic remodeling of bone and also play important physiologic and pathologic roles in the dentofacial complex. Osteoclasts and odontoclasts are necessary for tooth eruption yet result in dental compromise when associated with permanent tooth internal or external resorption. The determinants that separate their physiologic and pathologic roles are not well delineated. Clinical cases of primary eruption failure and root resorption are challenging to treat. Mineralized tissue resorbing cells undergo a fairly well characterized series of differentiation stages driven by transcriptional mediators. Signal transduction via cytokines and integrin-mediated events comprise the detailed pathways operative in osteo/odontoclastic cells and may provide insights to their targeted regulation. A better understanding of the unique aspects of osteoclastogenesis and osteo/odontoclast function will facilitate effective development of new therapeutic approaches. This review presents the clinical challenges and delves into the cellular and biochemical aspects of the unique cells responsible for resorption of mineralized tissues of the craniofacial complex.
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Affiliation(s)
- Z Wang
- Department of Orthodontics and Pediatric Dentistry, University of Michigan, Ann Arbor, MI, USA
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Moodie G, Ferris D, Hertzog B, Wimmer N, Morgan H, Chen C, Mathiowitz E, Valentini R. Early Osteoblast Attachment, Spreading, and Focal Adhesions on RGD Coated Surfaces. ACTA ACUST UNITED AC 2011. [DOI: 10.1557/proc-550-207] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
AbstractCells recognize and interact with the extracellular matrix (ECM) through heterodimeric receptors known as integrins. The objective of our work is to immobilize integrin-stimulating peptides to bone-contacting implants in order to control cellular activity and response.We have previously demonstrated that cysteine (C) containing peptides self-assemble onto gold-coated substrates. Investigations have focused on the RGD (Arg-Gly-Asp) peptide sequence since it is found in several bone ECM proteins. Gold was first coated onto glass coverslips by evaporation and the peptide was applied in a 0.22 mM solution. Contact angle and surface plasmon resonance verified RGDC peptide attachment and formation of a monolayer.Rat calvarial osteoblasts isolated from six-day-old rat pups were used from passages one to three. Cell attachment at 20 minutes is 100% greater on RGDC than on CG (control peptides) or plain gold surfaces. Cells on RGDC also stain positively for vinculin, a protein which is present in focal adhesions (functional structures into which integrins assemble) whereas surfaces without integrin stimulating peptides do not. Scanning electron micrographs show cells to be more spread and have more processes at 20 minutes, 1, 3, and 24 hours on RGDC. Live video images of these surfaces from zero to three hours after plating confirmed earlier and greater cell spreading on RGDC.Ongoing in vitro experiments are investigating the long-term response of osteoblasts to RGDC and other immobilized peptides in terms of differentiation, matrix production, and integrin expression.
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Igwe J, Amini A, Mikael P, Laurencin C, Nukavarapu S. Nanostructured Scaffolds for Bone Tissue Engineering. ACTIVE IMPLANTS AND SCAFFOLDS FOR TISSUE REGENERATION 2011. [DOI: 10.1007/8415_2010_60] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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Shekaran A, García AJ. Extracellular matrix-mimetic adhesive biomaterials for bone repair. J Biomed Mater Res A 2010; 96:261-72. [PMID: 21105174 DOI: 10.1002/jbm.a.32979] [Citation(s) in RCA: 145] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2010] [Revised: 09/07/2010] [Accepted: 09/08/2010] [Indexed: 01/12/2023]
Abstract
Limited osseointegration of current orthopedic biomaterials contributes to the failure of implants such as arthroplasties, bone screws, and bone grafts, which present a large socioeconomic cost within the United States. These implant failures underscore the need for biomimetic approaches that modulate host cell-implant material responses to enhance implant osseointegration and bone formation. Bioinspired strategies have included functionalizing implants with extracellular matrix (ECM) proteins or ECM-derived peptides or protein fragments, which engage integrins and direct osteoblast adhesion and differentiation. This review discusses (1) bone ECM composition and key integrins implicated in osteogenic differentiation, (2) the use of implants functionalized with ECM-mimetic peptides/protein fragments, and (3) growth factor-derived peptides to promote the mechanical fixation of implants to bone and to enhance bone healing within large defects.
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Affiliation(s)
- Asha Shekaran
- Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, Georgia, USA
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Nrf2 and selenoproteins are essential for maintaining oxidative homeostasis in erythrocytes and protecting against hemolytic anemia. Blood 2010; 117:986-96. [PMID: 20978266 DOI: 10.1182/blood-2010-05-285817] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Reactive oxygen species (ROS) are highly destructive toward cellular macromolecules. However, moderate levels of ROS can contribute to normal cellular processes including signaling. Herein we evaluate the consequence of a pro-oxidant environment on hematopoietic homeostasis. The NF-E2 related factor 2 (Nrf2) transcription factor regulates genes related to ROS scavenging and detoxification. Nrf2 responds to altered cellular redox status, such as occurs with loss of antioxidant selenoproteins after deletion of the selenocysteine-tRNA gene (Trsp). Conditional knockout of the Trsp gene using Mx1-inducible Cre-recombinase leads to selenoprotein deficiency and anemia on a wild-type background, whereas Trsp:Nrf2 double deficiency dramatically exacerbates the anemia and increases intracellular hydrogen peroxide levels in erythroblasts. Results indicate that Nrf2 compensates for defective ROS scavenging when selenoproteins are lost from erythroid cells. We also observed thymus atrophy in single Trsp-conditional knockout mice, suggesting a requirement for selenoprotein function in T-cell differentiation within the thymus. Surprisingly, no changes were observed in the myelomonocytic or megakaryocytic populations. Therefore, our results show that selenoprotein activity and the Nrf2 gene battery are particularly important for oxidative homeostasis in erythrocytes and for the prevention of hemolytic anemia.
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Au AY, Au RY, Demko JL, McLaughlin RM, Eves BE, Frondoza CG. Consil bioactive glass particles enhance osteoblast proliferation and selectively modulate cell signaling pathways in vitro. J Biomed Mater Res A 2010; 94:380-8. [PMID: 20186728 DOI: 10.1002/jbm.a.32668] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Consil Bioglass is a commercially available bioactive glass formulation previously shown in clinical studies to support osteogenesis and the repair of bony defects in dogs and cats. Previous in vitro studies confirm that Consil particles are able to bond directly with bone while promoting osteoblast proliferation and extracellular matrix production. However, the cellular mechanisms mediating their clinical effect remain unclear. This study evaluated whether enhancement of osteoblast proliferation by Consil particles is associated with signal transduction. Consil particles maintained the osteoblast phenotype and enhanced proliferation of canine osteoblasts for up to 21 days in culture. Stimulation of proliferation and maintenance of phenotype expression were accompanied by the modulation of selective cell signaling pathways including integrins, the mitogen-activated protein kinases (MAPKs), and the immediate-early gene c-Jun. These genes have been documented to mediate osteoblast growth and differentiation. The signal transduction occurs in a time-dependent manner in which Consil particles induce a decrease in the pattern of MAPK and c-Jun gene transcription from 4 to 24 h and a subsequent return to control levels by 7 days in culture. Our observations suggest that Consil Bioglass particles may provide cues that enhance cell division necessary for facilitating bone regeneration and the repair of bony defects.
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Affiliation(s)
- Angela Y Au
- Nutramax Laboratories, Inc., 2208 Lakeside Boulevard, Edgewood, Maryland 21040, USA
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Takegahara N, Kang S, Nojima S, Takamatsu H, Okuno T, Kikutani H, Toyofuku T, Kumanogoh A. Integral roles of a guanine nucleotide exchange factor, FARP2, in osteoclast podosome rearrangements. FASEB J 2010; 24:4782-92. [PMID: 20702777 DOI: 10.1096/fj.10-158212] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Podosomes are recently rediscovered highly dynamic actin-rich structural and functional modules that form close contact with the surrounding substrate. They play a role in the control of migration, tissue invasion, and matrix remodeling of highly motile cells, including lymphocytes, macrophages, dendritic cells, and osteoclasts. In osteoclasts, the compaction of podosomes induces the formation of a tight adhesive contact, the sealing zone, which defines a subosteoclastic environment specialized for bone resorption. Integrins and the Rho family small GTPases are key regulators of podosome rearrangements. However, it remains to be determined how the activation of integrins and Rho family GTPases is regulated during osteoclast podosome rearrangements. Here, we demonstrate a crucial role for the FERM domain-containing guanine nucleotide exchange factor (GEF), FARP2, in osteoclast podosome rearrangements and resorbing activity. We determine by live cell imaging and biochemical assays that FARP2 is required for localized activation of GTP-bound Rac1 into podosome-ring like structures. In addition, FARP2 is relevant to integrin β3 activity during osteoclastogenesis. Furthermore, FARP2 deficiency results in reduced formation of multinucleated osteoclasts and resorption pits compared to wild-type osteoclasts (controls). Collectively, our findings reveal an integral role of FARP2 for regulation of Rac1 and integrin β3 throughout podosome rearrangement in osteoclastogenesis.
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Affiliation(s)
- Noriko Takegahara
- Department of Immunopathology, Research Institute for Microbial Diseases, Immunology Frontier Research Center, Osaka University, Suita, Japan
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Use of molecular beacons to image effects of titanium surface microstructure on beta1 integrin expression in live osteoblast-like cells. Biomaterials 2010; 31:7640-7. [PMID: 20674005 DOI: 10.1016/j.biomaterials.2010.07.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2010] [Accepted: 07/02/2010] [Indexed: 11/20/2022]
Abstract
This study used molecular beacon technology to examine substrate-dependent changes in integrin subunit expression in living cells. Molecular beacons are oligonucleotide probes that can be delivered into live cells to allow for real-time imaging of mRNA. They have a stem-loop hairpin structure with a fluorophore-quencher pair, which opens when bound to the target mRNA sequence, resulting in a fluorescent signal upon excitation. A novel molecular beacon that is specific to the beta1 integrin subunit mRNA was developed and used to image osteoblast-like MG63 cells in vitro on both glass and titanium surfaces of varying roughness. Specificity was verified by comparing the molecular beacon signal intensities to real-time PCR results in both wild-type cells and cells with shRNA knockdown of beta1 integrin mRNA. The molecular beacon was able to detect changes due to both surface microtopography and silencing of the mRNA target. The results showed that effects of the substrate on beta1 mRNA noted previously in confluent cultures were evident in pre-confluent cells as well, supporting the hypothesis that beta1 integrin pairs are important in proliferation as well as differentiation of osteoblasts. This technique overcomes the limitations of traditional gene assays (PCR, immunofluorescence) by allowing for the real-time measurement and tracking of specific mRNAs in individual live cells prior to confluence.
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Arpornmaeklong P, Brown SE, Wang Z, Krebsbach PH. Phenotypic characterization, osteoblastic differentiation, and bone regeneration capacity of human embryonic stem cell-derived mesenchymal stem cells. Stem Cells Dev 2009; 18:955-68. [PMID: 19327009 PMCID: PMC3032563 DOI: 10.1089/scd.2008.0310] [Citation(s) in RCA: 113] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2008] [Accepted: 01/21/2009] [Indexed: 01/14/2023] Open
Abstract
To enhance the understanding of differentiation patterns and bone formation capacity of hESCs, we determined (1) the temporal pattern of osteoblastic differentiation of human embryonic stem cell-derived mesenchymal stem cells (hESC-MSCs), (2) the influence of a three-dimensional matrix on the osteogenic differentiation of hESC-MSCs in long-term culture, and (3) the bone-forming capacity of osteoblast-like cells derived from hESC-MSCs in calvarial defects. Incubation of hESC-MSCs in osteogenic medium induced osteoblastic differentiation of hESC-MSCs into mature osteoblasts in a similar chronological pattern to human bone marrow stromal cells and primary osteoblasts. Osteogenic differentiation was enhanced by culturing the cells on three-dimensional collagen scaffolds. Fluorescent-activated cell sorting of alkaline phosphatase expressing cells was used to obtain an enriched osteogenic cell population for in vivo transplantation. The identification of green fluorescence protein and expression of human-specific nuclear antigen in osteocytes in newly formed bone verified the role of transplanted human cells in the bone regeneration process. The current cell culture model and osteogenic cell enrichment method could provide large numbers of osteoprogenitor cells for analysis of differentiation patterns and cell transplantation to regenerate skeletal defects.
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Affiliation(s)
- Premjit Arpornmaeklong
- Department of Biologic and Materials Sciences, University of Michigan School of Dentistry, Ann Arbor, Michigan 48109-1078, USA
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Hess K, Ushmorov A, Fiedler J, Brenner RE, Wirth T. TNFalpha promotes osteogenic differentiation of human mesenchymal stem cells by triggering the NF-kappaB signaling pathway. Bone 2009; 45:367-76. [PMID: 19414075 DOI: 10.1016/j.bone.2009.04.252] [Citation(s) in RCA: 194] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/24/2008] [Revised: 04/24/2009] [Accepted: 04/25/2009] [Indexed: 12/29/2022]
Abstract
Mesenchymal stem cells are multipotent cells able to differentiate into different mesenchymal lineages. Studies in the past had suggested that two of these mesenchymal differentiation directions, the chondrogenic and the myogenic differentiation, are negatively regulated by the transcription factor NF-kappaB. Although osteogenic differentiation has been extensively studied, the influence of NF-kappaB on this differentiation lineage was not subject of detailed analyses in the past. We have analyzed the consequences of TNF-alpha treatment and genetic manipulation of the NF-kappaB pathway for osteogenic differentiation of hMSCs. Treatment of hMSCs during differentiation with TNF-alpha activates NF-kappaB and this results in enhanced expression of osteogenetic proteins like bone morphogenetic protein2 (BMP-2) and alkaline phosphatase (ALP). In addition, enhanced matrix mineralization was observed. The direct contribution of the NF-kappaB pathway was confirmed in cells that express a constitutively active version of the NF-kappaB-inducing kinase IKK2 (CA-IKK2). The IKK2/NF-kappaB-induced BMP-2 up-regulation results in the enhancement of RUNX2 and Osterix expression, two critical regulators of the osteogenic differentiation program. Interestingly, a genetic block of the NF-kappaB pathway did not interfere with osteogenic differentiation. We conclude that TNFalpha mediated NF-kappaB activation, although not absolutely required for BMP-2 expression and matrix mineralization nevertheless supports osteogenic differentiation and matrix mineralization by increasing BMP-2 expression. Our results therefore suggest that NF-kappaB activation may function in lineage selection during differentiation of hMSCs by fostering osteogenic differentiation at the expense of other differentiation lineages.
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Affiliation(s)
- Katrin Hess
- Institute of Physiological Chemistry, Ulm University, Albert-Einstein-Allee 11, D-89081 Ulm, Germany
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McNamara LM, Majeska RJ, Weinbaum S, Friedrich V, Schaffler MB. Attachment of osteocyte cell processes to the bone matrix. Anat Rec (Hoboken) 2009; 292:355-63. [PMID: 19248169 DOI: 10.1002/ar.20869] [Citation(s) in RCA: 133] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
In order for osteocytes to perceive mechanical information and regulate bone remodeling accordingly they must be anchored to their extracellular matrix (ECM). To date the nature of this attachment is not understood. Osteocytes are embedded in mineralized bone matrix, but maintain a pericellular space (50-80 nm) to facilitate fluid flow and transport of metabolites. This provides a spatial limit for their attachment to bone matrix. Integrins are cell adhesion proteins that may play a role in osteocyte attachment. However, integrin attachments require proximity between the ECM, cell membrane, and cytoskeleton, which conflicts with the osteocytes requirement for a pericellular fluid space. In this study, we hypothesize that the challenge for osteocytes to attach to surrounding bone matrix, while also maintaining fluid-filled pericellular space, requires different "engineering" solutions than in other tissues that are not similarly constrained. Using novel rapid fixation techniques, to improve cell membrane and matrix protein preservation, and transmission electron microscopy, the attachment of osteocyte processes to their canalicular boundaries are quantified. We report that the canalicular wall is wave-like with periodic conical protrusions extending into the pericellular space. By immunohistochemistry we identify that the integrin alphavbeta3 may play a role in attachment at these complexes; a punctate pattern of staining of beta3 along the canalicular wall was consistent with observations of periodic protrusions extending into the pericellular space. We propose that during osteocyte attachment the pericellular space is periodically interrupted by underlying collagen fibrils that attach directly to the cell process membrane via integrin-attachments.
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Affiliation(s)
- L M McNamara
- Leni and Peter W. May Department of Orthopaedics, Mount Sinai School of Medicine, New York, NY, USA
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Abstract
Successful bone repair is judged in achieving restitution of space and mechanical integrity, and in regaining function. When the biology or anatomy are insufficient to attain a full repair, therapeutic use of graft material has been used to omit compliance features such as strain tolerance, reduced stiffness, and attenuated strength, and instead promote primary or membranous-type bone formation within the physical approximation of a graft material. The challenge of most conductive materials is that they emerge from a static platform and in placement force the living system to adapt to placement, dimension, different properties, and eventually are only successful in degradation and replacement, or in integration. The synergy and interdependency between adhesion, ECM, and proteolysis are important concepts that must be understood to engineer scaffolds capable of holding up to standards which are more than cell decoration. Moreover, the reactive specificity to loading, degradation, therapeutic delivery during absorption remains a key aim of both academic and industrial designs. Achieving conductivity comes with challenges of best fit integration, delivery, and in integrated modeling. The more liquid is the delivery, the more modular the components, and adaptive the matrix to meeting the intended application, the more likely that the conductivity will not be excluded by the morphology of the injury site. Considerations for osteoconductive materials for bone repair and replacement have developed conceptually and advanced parallel with a better understanding of not only bone biology but of materials science. First models of material replacements utilized a reductionist-constructionist logic; define the constituents of the material in terms of its morphology and chemical composition, and then engineer material with similar content and properties as a means of accommodating a replacement. Unfortunately for biologic systems, empiric formulation is insufficient to promote adequate integration in a timely fashion. Future matrices will need to translate their biological surfaces as more than a scaffold to be decorated with cells. Conductivity will be improved by formulations that enhance function, further extended from understanding what composition best suits cell attachment, and be adopted by conveniences of delivery that meet those criteria.
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Affiliation(s)
- Timothy Ganey
- Department of Orthopaedics, Atlanta Medical Center, Atlanta, GA
| | - William Hutton
- Emory Orthopaedics & Spine Center, Atlanta Medical Center, Atlanta, GA
| | - Hans Jörg Meisel
- Department of Neurosurgery, BG-Clinic Bergmannstrost, Halle, Germany
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