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CpG Oligodeoxynucleotides Inhibit RANKL-Induced Osteoclast Formation by Upregulating A20 Deubiquitinase in RAW 264.7 Cells. Mediators Inflamm 2022; 2022:5255935. [PMID: 36091665 PMCID: PMC9453122 DOI: 10.1155/2022/5255935] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Accepted: 08/06/2022] [Indexed: 11/29/2022] Open
Abstract
Objective Activation of toll-like receptor 9 (TLR9) has been proposed to play an inhibitory role in RANKL-induced osteoclastogenesis. A20 deubiquitinase has been found to be related to bone loss. This study investigated the role of CpG oligodeoxynucleotides (CpG-ODNs) through regulation of A20 deubiquitinase in RANKL-induced osteoclast formation. Methods RAW 264.7 cells, a murine monocyte-macrophage cell line, were incubated with or without CpG-ODN in the presence of RANKL. Osteoclast-specific genes and their related signaling molecules were measured by real-time quantitative polymerase chain reaction and Western blot assay. Morphological assessment for osteoclast formation was performed using tartrate-resistant acid phosphatase (TRAP) staining and F-actin ring formation staining. Results RANKL-induced osteoclast-related genes and proteins, c-Fos, NFATc1, TRAP, cathepsin K, and carbonic anhydrase II were significantly inhibited in RAW 264.7 cells stimulated with CpG-ODN. CpG-ODN attenuated TNF receptor-associated factor 6 (TRAF6), p-IκBα, and p-NF-κB expression in RAW 264 cells mediated by RANKL. CpG-ODN increased A20 gene and proteins in time-dependent manner. A20 expression under costimulation with CpG-ODN and RANKL was more decreased than under stimulation with RANKL alone. Cells transfected with A20 siRNA augmented expression of osteoclast-related genes and proteins. Number of TRAP-positive cells transfected with A20 siRNA was higher than those transfected with NC siRNA. A20 expression in cells transfected with IL-1β siRNA in the presence of both RANKL and CpG-ODN was more decreased than those with NC siRNA. Conclusion This study showed that CpG-ODN suppressed RANKL-induced osteoclast formation through regulation of the A20-TRAF6 axis in RAW 264.7 cells.
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Ding P, Tan Q, Wei Z, Chen Q, Wang C, Qi L, Wen L, Zhang C, Yao C. Toll-like receptor 9 deficiency induces osteoclastic bone loss via gut microbiota-associated systemic chronic inflammation. Bone Res 2022; 10:42. [PMID: 35624094 PMCID: PMC9142495 DOI: 10.1038/s41413-022-00210-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Revised: 02/06/2022] [Accepted: 03/13/2022] [Indexed: 02/08/2023] Open
Abstract
Toll-like receptors (TLRs) play pivotal roles in inflammation and provide important links between the immune and skeletal systems. Although the activation of TLRs may affect osteoclast differentiation and bone metabolism, whether and how TLRs are required for normal bone remodeling remains to be fully explored. In the current study, we show for the first time that TLR9-/- mice exhibit a low bone mass and low-grade systemic chronic inflammation, which is characterized by the expansion of CD4+ T cells and increased levels of inflammatory cytokines, including TNFα, RANKL, and IL1β. The increased levels of these cytokines significantly promote osteoclastogenesis and induce bone loss. Importantly, TLR9 deletion alters the gut microbiota, and this dysbiosis is the basis of the systemic inflammation and bone loss observed in TLR9-/- mice. Furthermore, through single-cell RNA sequencing, we identified myeloid-biased hematopoiesis in the bone marrow of TLR9-/- mice and determined that the increase in myelopoiesis, likely caused by the adaptation of hematopoietic stem cells to systemic inflammation, also contributes to inflammation-induced osteoclastogenesis and subsequent bone loss in TLR9-/- mice. Thus, our study provides novel evidence that TLR9 signaling connects the gut microbiota, immune system, and bone and is critical in maintaining the homeostasis of inflammation, hematopoiesis, and bone metabolism under normal conditions.
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Affiliation(s)
- Peng Ding
- Department of Orthopedic Surgery, Shanghai Jiaotong University affiliated Sixth People's Hospital, Shanghai, China
| | - Qiyuan Tan
- Department of Endocrinology and Metabolism, Shanghai Jiaotong University affiliated Sixth People's Hospital, Shanghai, China
| | - Zhanying Wei
- Department of Osteoporosis and Skeletal Disorders, Shanghai Jiaotong University affiliated Sixth People's Hospital, Shanghai, China
| | - Qiyu Chen
- Department of Orthopedic Surgery, Shanghai Jiaotong University affiliated Sixth People's Hospital, Shanghai, China
| | - Chun Wang
- Department of Osteoporosis and Skeletal Disorders, Shanghai Jiaotong University affiliated Sixth People's Hospital, Shanghai, China
| | - Luyue Qi
- Department of Endocrinology and Metabolism, Second Affiliated Hospital of Soochow University, Suzhou, China
| | - Li Wen
- Section of Endocrinology, Department of Internal Medicine, Yale University School of Medicine, New Haven, USA
| | - Changqing Zhang
- Department of Orthopedic Surgery, Shanghai Jiaotong University affiliated Sixth People's Hospital, Shanghai, China.
| | - Chen Yao
- Department of Orthopedic Surgery, Shanghai Jiaotong University affiliated Sixth People's Hospital, Shanghai, China.
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Shinji S, Umezawa K, Nihashi Y, Nakamura S, Shimosato T, Takaya T. Identification of the Myogenetic Oligodeoxynucleotides (myoDNs) That Promote Differentiation of Skeletal Muscle Myoblasts by Targeting Nucleolin. Front Cell Dev Biol 2021; 8:616706. [PMID: 33585451 PMCID: PMC7874222 DOI: 10.3389/fcell.2020.616706] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Accepted: 12/07/2020] [Indexed: 12/18/2022] Open
Abstract
Herein we report that the 18-base telomeric oligodeoxynucleotides (ODNs) designed from the Lactobacillus rhamnosus GG genome promote differentiation of skeletal muscle myoblasts which are myogenic precursor cells. We termed these myogenetic ODNs (myoDNs). The activity of one of the myoDNs, iSN04, was independent of Toll-like receptors, but dependent on its conformational state. Molecular simulation and iSN04 mutants revealed stacking of the 13-15th guanines as a core structure for iSN04. The alkaloid berberine bound to the guanine stack and enhanced iSN04 activity, probably by stabilizing and optimizing iSN04 conformation. We further identified nucleolin as an iSN04-binding protein. Results showed that iSN04 antagonizes nucleolin, increases the levels of p53 protein translationally suppressed by nucleolin, and eventually induces myotube formation by modulating the expression of genes involved in myogenic differentiation and cell cycle arrest. This study shows that bacterial-derived myoDNs serve as aptamers and are potential nucleic acid drugs directly targeting myoblasts.
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Affiliation(s)
- Sayaka Shinji
- Department of Agriculture, Graduate School of Science and Technology, Shinshu University, Nagano, Japan
| | - Koji Umezawa
- Department of Agricultural and Life Science, Faculty of Agriculture, Shinshu University, Nagano, Japan
- Department of Biomolecular Innovation, Institute for Biomedical Sciences, Shinshu University, Nagano, Japan
| | - Yuma Nihashi
- Department of Science and Technology, Graduate School of Medicine, Science and Technology, Shinshu University, Nagano, Japan
| | - Shunichi Nakamura
- Department of Agriculture, Graduate School of Science and Technology, Shinshu University, Nagano, Japan
| | - Takeshi Shimosato
- Department of Agriculture, Graduate School of Science and Technology, Shinshu University, Nagano, Japan
- Department of Agricultural and Life Science, Faculty of Agriculture, Shinshu University, Nagano, Japan
- Department of Biomolecular Innovation, Institute for Biomedical Sciences, Shinshu University, Nagano, Japan
- Department of Science and Technology, Graduate School of Medicine, Science and Technology, Shinshu University, Nagano, Japan
| | - Tomohide Takaya
- Department of Agriculture, Graduate School of Science and Technology, Shinshu University, Nagano, Japan
- Department of Agricultural and Life Science, Faculty of Agriculture, Shinshu University, Nagano, Japan
- Department of Biomolecular Innovation, Institute for Biomedical Sciences, Shinshu University, Nagano, Japan
- Department of Science and Technology, Graduate School of Medicine, Science and Technology, Shinshu University, Nagano, Japan
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Yu W, Zheng Y, Li H, Lin H, Chen Z, Tian Y, Chen H, Zhang P, Xu X, Shen Y. The Toll-like receptor ligand, CpG oligodeoxynucleotides, regulate proliferation and osteogenic differentiation of osteoblast. J Orthop Surg Res 2020; 15:327. [PMID: 32795334 PMCID: PMC7427903 DOI: 10.1186/s13018-020-01844-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/09/2020] [Accepted: 07/30/2020] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND This study aimed to investigate the regulation of CpG oligodeoxynucleotides (ODNs) on proliferation and osteogenic differentiation of MC3T3 cells. METHODS The laser co-focusing and flow cytometry assay were employed to detect cell uptake of CpG ODN 2006. Twelve ODNs were sythesized, and their effects on proliferation and differentiation were detected by MTT and alkaline phosphatase (ALP) activity assay. Flow cytometry assay was used to examine the regulation of CpG ODN on cell cycle. Quantitative real-time PCR (qRT-PCR) and western blot were used to evaluate the regulation of CpG ODN on mRNA and protein expression of osteogenic differentiation genes. RESULTS The phosphorothioate CpG ODN 2006 could efficiently enter the MC3T3 cells in 1 h and locate in the cytoplasm. The MTT assay demonstrated CpG ODNs could promote MC3T3 cell proliferation and differentiation in the early stage, and gradually attenuated along with the increase of treating time, except for BW001 and FC001. qRT-PCR assay demonstrated that all the 12 CpG ODNs could promote the relative expression level of osteogenic differentiated genes, SP7 and OCN. In addition, western blot analysis suggested the CpG ODNs of BW001 and FC001 could increase the protein expression of P27Kip1 and Runx2 and decrease the protein expression of cyclin D1. CONCLUSION The selected CpGODNs may be a potential gene therapy for bone regeneration of periodontitis.
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Affiliation(s)
- Wenwen Yu
- Department of Periodontics, School and hospital of Stomatology, Jilin University, 1500 Qinghua Road, Changchun, Jilin, 130021, China
- Department of Orthodontics, Tianjin Key Laboratory of Oral and Maxillofacial Function Reconstruction; Tianjin Stomatological Hospital; Hospital of Stomatology, Nankai University, 75 Dagu North Road, Tianjin, 300041, China
| | - Yi Zheng
- Department of Periodontics, School and hospital of Stomatology, Jilin University, 1500 Qinghua Road, Changchun, Jilin, 130021, China
| | - Hongyan Li
- Department of Periodontics, School and hospital of Stomatology, Jilin University, 1500 Qinghua Road, Changchun, Jilin, 130021, China
| | - Hongbing Lin
- Department of Periodontics, School and hospital of Stomatology, Jilin University, 1500 Qinghua Road, Changchun, Jilin, 130021, China
| | - Zhen Chen
- Department of Periodontics, School and hospital of Stomatology, Jilin University, 1500 Qinghua Road, Changchun, Jilin, 130021, China
| | - Yue Tian
- Department of Periodontics, School and hospital of Stomatology, Jilin University, 1500 Qinghua Road, Changchun, Jilin, 130021, China
| | - Huishan Chen
- Department of Periodontics, School and hospital of Stomatology, Jilin University, 1500 Qinghua Road, Changchun, Jilin, 130021, China
| | - Peipei Zhang
- Department of Periodontics, School and hospital of Stomatology, Jilin University, 1500 Qinghua Road, Changchun, Jilin, 130021, China
| | - Xiaowei Xu
- Department of Periodontics, School and hospital of Stomatology, Jilin University, 1500 Qinghua Road, Changchun, Jilin, 130021, China
| | - Yuqin Shen
- Department of Periodontics, School and hospital of Stomatology, Jilin University, 1500 Qinghua Road, Changchun, Jilin, 130021, China.
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Wang H, Yu W, Li H, Zheng Y, Chen Z, Lin H, Shen Y. N-Acetyl-l-Leucine-Polyethyleneimine-Mediated Delivery of CpG Oligodeoxynucleotides 2006 Inhibits RAW264.7 Cell Osteoclastogenesis. Drug Des Devel Ther 2020; 14:2657-2665. [PMID: 32764870 PMCID: PMC7368329 DOI: 10.2147/dddt.s241826] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Accepted: 06/03/2020] [Indexed: 11/23/2022] Open
Abstract
INTRODUCTION CpG oligodeoxynucleotides (CpG ODN) play important roles in resisting inflammation and bone resorption. However, the inherent instability and rapid degradation hinder their wider application. This study aimed to evaluate whether N-acetyl-L-leucine-modified polyethyleneimine (N-Ac-L-Leu-PEI) could effectively deliver CpG ODN 2006 to RAW264.7 cells and and if it can regulate osteoclastogenesis in vitro. MATERIALS AND METHODS Gel retardation assay was conducted to evaluate whether N- Ac-L-Leu-PEI and CpG ODN could form a stable complex. RAW264.7 cells were divided into four groups of control group, ODN group, phosphorothioate ODN group and N-Ac-L-Leu-PEI/ODN group. Fluorescence assay was conducted to evaluate the transfection rate of ODNs in different groups. Cell viability was determined by MTT assay. Cell apoptosis was determined by live-dead cell staining and flow cytometry assay. Relative expression levels of osteoclastic differentiation factors, including Nfatc, c-fos, receptor activator of nuclear factor κB (RANK), and matrix metalloproteinase 9 (MMP9), were determined by real-time PCR and Western blot. RESULTS N-Ac-L-Leu-PEI and CpG ODN could form a stable complex at a mass ratio of 1:1 (w:w). MTT assay showed that the cell viability of N-Ac-L-Leu-PEI was relatively high even at a mass ratio of 8 μg/mL. The transfection rate of N-Ac-L-Leu-PEI-ODN complex was higher than 90%. The cell proliferation and apoptosis was significantly enhanced in N-Ac-L-Leu-PEI- CpG ODN group when compared to those in phosphorothioate CpG ODN. The expression levels of Nfatc, c-fos, RANK, and MMP9 were significantly decreased in N-Ac-L-Leu-PEI/ODN complex group. DISCUSSION N-Ac-L-Leu-PEI could be a potential gene vehicle for the prevention of periodontitis-mediated bone resorption.
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Affiliation(s)
- Huining Wang
- Department of Periodontics, Institute of Stomatology, School and Hospital of Stomatology, Wenzhou Medical University, Wenzhou325027, Zhejiang Province, People’s Republic of China
| | - Wenwen Yu
- Department of Orthodontics, School and Hospital of Stomatology, Jilin University, Changchun, Jilin130021, People’s Republic of China
- Department of Orthodontics, Tianjin Stomatological Hospital, Nankai University, Tianjin300041, People’s Republic of China
| | - Hongyan Li
- Department of Periodontics, School and Hospital of Stomatology, Jilin University, Changchun, Jilin130021,People’s Republic of China
| | - Yi Zheng
- Department of Periodontics, School and Hospital of Stomatology, Jilin University, Changchun, Jilin130021,People’s Republic of China
- Key Laboratory of Organ Regeneration & Transplantation of the Ministry of Education, The First Hospital of Jilin University, Changchun, Jilin130061, People’s Republic of China
| | - Zhen Chen
- Department of Periodontics, School and Hospital of Stomatology, Jilin University, Changchun, Jilin130021,People’s Republic of China
| | - Hongbing Lin
- Department of Periodontics, School and Hospital of Stomatology, Jilin University, Changchun, Jilin130021,People’s Republic of China
| | - Yuqin Shen
- Department of Periodontics, School and Hospital of Stomatology, Jilin University, Changchun, Jilin130021,People’s Republic of China
- Key Laboratory of Organ Regeneration & Transplantation of the Ministry of Education, The First Hospital of Jilin University, Changchun, Jilin130061, People’s Republic of China
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Zheng Y, Yu W, Li H, Lin H, Chen Z, Chen H, Zhang P, Tian Y, Xu X, Shen Y. CpG oligodeoxynucleotides inhibit the proliferation and osteoclastic differentiation of RAW264.7 cells. RSC Adv 2020; 10:14885-14891. [PMID: 35497169 PMCID: PMC9052049 DOI: 10.1039/c9ra11036d] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2019] [Accepted: 03/31/2020] [Indexed: 01/21/2023] Open
Abstract
Clinical prevention and treatment of periodontitis-induced bone absorption remains a challenge. The anti-infection role of CpG oligodeoxynucleotides (CpG ODNs) is well known; however, their effect on osteoclasts is still unclear. Here, we show that some CpG ODNs can regulate osteoclastogenesis of RAW264.7 cells. The phosphorothioate CpG ODN was efficiently taken up by the cells within 1 h and distributed in the cytoplasm. BW006, YW001, YW002, and FC004 CpG ODNs significantly repressed cell proliferation by targeting several cyclin proteins to arrest the cells in the G2 phase and to further initiate cell apoptosis. Regarding differentiation, we selected six CpG ODNs (FC002, BW006, YW002, YW001, FC004, and MT01) that markedly inhibited the gene expression levels of Nfatc, c-fos, RANK, and MMP9. TRAP staining showed that only YW002, YW001, and FC004 suppressed osteoclast generation and maturation. These three CpG ODNs dramatically declined the protein levels of osteoclastogenic proteins by elevating the ratio of OPG/RANKL and also downregulating the inflammatory factors (TNF-α, IL-1β, IL-6, and IL-17) at different stages. Thus, the selected CpG ODNs may be a potential molecular therapy for the prevention and treatment of periodontitis-mediated bone resorption.
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Affiliation(s)
- Yi Zheng
- Department of Periodontics, Hospital of Stomatology, Jilin University 1500 Qinghua Road Changchun 130021 Jilin China .,Key Laboratory of Organ Regeneration & Transplantation of the Ministry of Education, The First Hospital of Jilin University Changchun 130061 Jilin China
| | - Wenwen Yu
- Department of Orthodontics, Hospital of Stomatology, Jilin University 1500 Qinghua Road Changchun 130021 China.,Department of Orthodontics, Tianjin Stomatological Hospital, Nankai University Tianjin 300041 China
| | - Hongyan Li
- Department of Periodontics, Hospital of Stomatology, Jilin University 1500 Qinghua Road Changchun 130021 Jilin China
| | - Hongbing Lin
- Department of Periodontics, Hospital of Stomatology, Jilin University 1500 Qinghua Road Changchun 130021 Jilin China .,Key Laboratory of Organ Regeneration & Transplantation of the Ministry of Education, The First Hospital of Jilin University Changchun 130061 Jilin China
| | - Zhen Chen
- Department of Periodontics, Hospital of Stomatology, Jilin University 1500 Qinghua Road Changchun 130021 Jilin China
| | - Huishan Chen
- Department of Periodontics, Hospital of Stomatology, Jilin University 1500 Qinghua Road Changchun 130021 Jilin China
| | - Peipei Zhang
- Department of Periodontics, Hospital of Stomatology, Jilin University 1500 Qinghua Road Changchun 130021 Jilin China
| | - Yue Tian
- Department of Periodontics, Hospital of Stomatology, Jilin University 1500 Qinghua Road Changchun 130021 Jilin China
| | - Xiaowei Xu
- Department of Periodontics, Hospital of Stomatology, Jilin University 1500 Qinghua Road Changchun 130021 Jilin China
| | - Yuqin Shen
- Department of Periodontics, Hospital of Stomatology, Jilin University 1500 Qinghua Road Changchun 130021 Jilin China .,Key Laboratory of Organ Regeneration & Transplantation of the Ministry of Education, The First Hospital of Jilin University Changchun 130061 Jilin China
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Souza PPC, Lerner UH. Finding a Toll on the Route: The Fate of Osteoclast Progenitors After Toll-Like Receptor Activation. Front Immunol 2019; 10:1663. [PMID: 31379855 PMCID: PMC6652233 DOI: 10.3389/fimmu.2019.01663] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Accepted: 07/03/2019] [Indexed: 12/14/2022] Open
Abstract
M-CSF and RANKL are two crucial cytokines stimulating differentiation of mature, bone resorbing, multinucleated osteoclasts from mononucleated progenitor cells in the monocyte/macrophage lineage. In addition to the receptors for M-CSF and RANKL, osteoclast progenitor cells express receptors for several other pro- and anti-osteoclastogenic cytokines, which also regulate osteoclast formation by affecting signaling downstream M-CSF and RANKL receptors. Similar to many other cells originating from myeloid hematopoetic stem cells, also osteoclast progenitors express toll-like receptors (TLRs). Nine murine TLRs are expressed in the progenitors and all, with the exception of TLR2 and TLR4, are downregulated during osteoclastogenesis. Activation of TLR2, TLR4, and TLR9, but not TLR5, in osteoclast progenitors stimulated with M-CSF and RANKL arrests differentiation along the osteoclastic lineage and keeps the cells at a macrophage stage. When the progenitors are primed with M-CSF/RANKL and then stimulated with agonists for TLR2, TLR4, or TLR9 in the presence of M-CSF, but in the absence of RANKL, the cells differentiate to mature, bone resorbing osteoclasts. TLR 2, 4, 5, and 9 are also expressed on osteoblasts and their activation increases osteoclast differentiation by an indirect mechanism through stimulation of RANKL. In mice, treatment with agonists for TLR2, 4, and 5 results in osteoclast formation and extensive bone loss. It remains to be shown the relative importance of inhibitory and stimulatory effects by TLRs on osteoclast progenitors and the role of RANKL produced by TLR stimulated osteoblasts, for the bone resorbing effects in vivo.
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Affiliation(s)
- Pedro P C Souza
- Faculty of Dentistry, Federal University of Goiás, Goiânia, Brazil
| | - Ulf H Lerner
- Centre for Bone and Arthritis Research at Department of Internal Medicine and Clinical Nutrition, Institute for Medicine, Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden
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Saint-Pastou Terrier C, Gasque P. Bone responses in health and infectious diseases: A focus on osteoblasts. J Infect 2017; 75:281-292. [PMID: 28778751 DOI: 10.1016/j.jinf.2017.07.007] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Revised: 07/13/2017] [Accepted: 07/26/2017] [Indexed: 12/16/2022]
Abstract
Historically, bone was thought to be immunologically inactive with the sole function of supporting locomotion and ensuring stromaness functions as a major lymphoid organ. However, a myriad of pathogens (bacteria such as staphylococcus as well as viruses including alphaviruses, HIV or HCV) can invade the bone. These pathogens can cause apoptosis, autophagy and necrosis of osteoblasts and lead to lymphopenia and immune paralysis. There are now several detailed studies on how osteoblasts contribute to innate immune and inflammatory responses; indeed, osteoblasts in concert with resident macrophages can engage an armory of defense mechanisms capable of detecting and controlling pathogen evasion mechanisms. Osteoblasts can express the so-called pattern recognition receptors such as TOLL-like receptors involved in the detection for example of lipids and unique sugars (polysaccharides and polyriboses) expressed by bacteria or viruses (e.g. LPS and RNA respectively). Activated osteoblasts can produce interferon type I, cytokines, chemokines and interferon-stimulated proteins through autocrine and paracrine mechanisms to control for viral replication and to promote phagocytosis or lysis of bacteria for example by defensins. Uncontrolled and sustained innate immune activation of infected osteoblasts will also lead to an imbalance in the production of osteoclastogenic factors such as RANKL and osteoprotegerin involved in bone repair.
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Affiliation(s)
- Cécile Saint-Pastou Terrier
- Université de La Réunion, CNRS 9192, INSERM U1187, IRD 249, Unité Mixte Processus Infectieux en Milieu Insulaire Tropical (PIMIT), Plateforme Technologique CYROI, Sainte-Clotilde, La Réunion, France
| | - Philippe Gasque
- Université de La Réunion, CNRS 9192, INSERM U1187, IRD 249, Unité Mixte Processus Infectieux en Milieu Insulaire Tropical (PIMIT), Plateforme Technologique CYROI, Sainte-Clotilde, La Réunion, France; Laboratoire de Biologie, secteur Laboratoire d'immunologie clinique et expérimentale ZOI (LICE OI), CHU La Réunion site Félix Guyon, St Denis, La Réunion, France.
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Du X, Man D, Li D, Kang N, Dong P, Fang D, Zhu X, Zhou Y. The Effect of Specific Oligonucleotides on the Proliferation of Human Bone-Marrow Mesenchymal Stem Cells. J HARD TISSUE BIOL 2014. [DOI: 10.2485/jhtb.23.343] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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10
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Dahl C, Søgaard AJ, Tell GS, Flaten TP, Krogh T, Aamodt G. Is the quality of drinking water a risk factor for self-reported forearm fractures? Cohort of Norway. Osteoporos Int 2013; 24:541-51. [PMID: 22569744 DOI: 10.1007/s00198-012-1989-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/27/2011] [Accepted: 03/26/2012] [Indexed: 10/28/2022]
Abstract
SUMMARY Compared to pH ≥7.0 in Norwegian municipal drinking water, pH <7.0 increased the risk of forearm fractures in the population-based Cohort of Norway (CONOR; n = 127,272). The association was attenuated (p > 0.05) after adjustments for indicators of bacteria and organic matter, which may signify an association between poor drinking water and bone health. INTRODUCTION The Norwegian population has the highest rate of fractures ever reported. A large variation in fracture rate both between and within countries indicates that an environmental factor, such as the quality of drinking water, could be one of the causes of the disparities. Our aim was to investigate a possible association between pH (an important parameter for water quality) and self-reported forearm fracture and to examine whether other water quality factors could account for this association. METHODS Using Geographic Information Systems, information on the quality of drinking water was linked to CONOR (n = 127,272; mean age, 50.2 ± 15.8 years), a database comprising ten regional epidemiological health surveys from across the country in the time period 1994-2003. RESULTS The highest risk of forearm fracture was found at a pH of around 6.75, with a decreasing risk toward both higher and lower pH values. The increased adjusted odds of forearm fracture in men consuming municipal drinking water with pH <7.0 compared to water with pH ≥7.0 was odds ratio (OR) = 1.19 (95 % CI, 1.14, 1.25), and the corresponding increased odds in women was OR = 1.14 (95 % CI, 1.08, 1.19). This association was attenuated (p > 0.05) after further adjustments for other water quality factors (color grade, intestinal enterococci, and Clostridium perfringens). CONCLUSIONS Our findings indicate a higher risk of fracture when consuming water of an acidic pH; however, the risk does not only seem to be due to the acidity level per se, but also to other aspects of water quality associated with pH.
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Affiliation(s)
- C Dahl
- Division of Epidemiology, Norwegian Institute of Public Health, P.O. Box 4404, Nydalen, 0403, Oslo, Norway.
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A specific oligodeoxynucleotide promotes the differentiation of osteoblasts via ERK and p38 MAPK pathways. Int J Mol Sci 2012; 13:7902-7914. [PMID: 22942680 PMCID: PMC3430211 DOI: 10.3390/ijms13077902] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2012] [Revised: 05/11/2012] [Accepted: 06/15/2012] [Indexed: 02/07/2023] Open
Abstract
A specific oligodeoxynucleotide (ODN), ODN MT01, was found to have positive effects on the proliferation and activation of the osteoblast-like cell line MG 63. In this study, the detailed signaling pathways in which ODN MT01 promoted the differentiation of osteoblasts were systematically examined. ODN MT01 enhanced the expression of osteogenic marker genes, such as osteocalcin and type I collagen. Furthermore, ODN MT01 activated Runx2 phosphorylation via ERK1/2 mitogen-activated protein kinase (MAPK) and p38 MAPK. Consistently, ODN MT01 induced up-regulation of osteocalcin, alkaline phosphatase (ALP) and type I collagen, which was inhibited by pre-treatment with the ERK1/2 inhibitor U0126 and the p38 inhibitor SB203580. These results suggest that the ERK1/2 and p38 MAPK pathways, as well as Runx2 activation, are involved in ODN MT01-induced up-regulation of osteocalcin, type I collagen and the activity of ALP in MG 63 cells.
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Shen Y, Feng Z, Lin C, Hou X, Wang X, Wang J, Yu Y, Wang L, Sun X. An oligodeoxynucleotide that induces differentiation of bone marrow mesenchymal stem cells to osteoblasts in vitro and reduces alveolar bone loss in rats with periodontitis. Int J Mol Sci 2012; 13:2877-2892. [PMID: 22489131 PMCID: PMC3317693 DOI: 10.3390/ijms13032877] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2012] [Revised: 02/19/2012] [Accepted: 02/24/2012] [Indexed: 01/01/2023] Open
Abstract
To investigate the effect of oligodeoxynucleotides (ODNs) on the differentiation of rat bone marrow mesenchymal stem cells (BMSCs) to osteoblasts, in order to find a candidate ODN with potential for the treatment of periodontitis, a series of ODNs were designed and selected to test their effect on the promotion of the differentiation of BMSCs to osteoblasts in vitro and on the repair of periodontal tissue in rats with periodontitis. It was found that MT01, one of the ODNs with the sequences of human mitochondrial DNA, stimulated the proliferation of BMSCs, the differentiation of BMSCs to osteoblasts and mRNA expression of bone-associated factors including Runx2, Osterix, OPG, RANKL and collagen I in vitro. In vivo study showed that MT01 prevented the loss of alveolar bone in the rats with periodontitis and induced the production of proteins of OPG and Osterix in the bone tissue. These results indicated that MT01 could induce differentiation of BMSCs to osteoblasts and inhibit the alveolar bone absorption in rats with periodontitis.
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Affiliation(s)
- Yuqin Shen
- Department of Periodontics, School of Stomatology, Jilin University, 1500 Qinghua Road, Changchun 130021, China; E-Mails: (Y.S.); (C.L.)
| | - Zhiyuan Feng
- Department of Orthodontics, People’s Hospital of Shanxi, 29 Shuangta Road, Taiyuan 030012, China; E-Mail:
- Department of Orthodontics, School of Stomatology, Jilin University, 1500 Qinghua Road, Changchun 130021, China; E-Mails: (X.H.); (J.W.)
| | - Chongtao Lin
- Department of Periodontics, School of Stomatology, Jilin University, 1500 Qinghua Road, Changchun 130021, China; E-Mails: (Y.S.); (C.L.)
| | - Xu Hou
- Department of Orthodontics, School of Stomatology, Jilin University, 1500 Qinghua Road, Changchun 130021, China; E-Mails: (X.H.); (J.W.)
| | - Xueju Wang
- Department of Pathology, China-Japan Union Hospital, Jilin University, 1500 Qinghua Road, Changchun 130021, China; E-Mail:
| | - Jing Wang
- Department of Orthodontics, School of Stomatology, Jilin University, 1500 Qinghua Road, Changchun 130021, China; E-Mails: (X.H.); (J.W.)
| | - Yongli Yu
- Department of Immunology, Medical College of Norman Bethune, Jilin University, 1500 Qinghua Road, Changchun 130021, China; E-Mail:
| | - Liying Wang
- Department of Molecular Biology, Medical College of Norman Bethune, Jilin University, 1500 Qinghua Road, Changchun 130021, China
| | - Xinhua Sun
- Department of Orthodontics, School of Stomatology, Jilin University, 1500 Qinghua Road, Changchun 130021, China; E-Mails: (X.H.); (J.W.)
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Feng Z, Shen Y, Wang L, Cheng L, Wang J, Li Q, Shi W, Sun X. An oligodeoxynucleotide with promising modulation activity for the proliferation and activation of osteoblast. Int J Mol Sci 2011; 12:2543-55. [PMID: 21731457 PMCID: PMC3127133 DOI: 10.3390/ijms12042543] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2011] [Revised: 04/06/2011] [Accepted: 04/07/2011] [Indexed: 12/22/2022] Open
Abstract
The paper explored the regulatory role of oligodeoxynucleotides (ODNs) with specific sequences in the proliferation and activation of osteoblast, using human osteoblast-like cell line MG 63 as the model. Through the administration of ODNs to MG 63 cells at a concentration of 1.0 μg/mL, ODN MT01 with positive effects on proliferation and activation of osteoblast was selected from 11 different ODNs by methyl thiazolyl tetrazolium (MTT) assay and alkaline phosphatase (ALP) activity measurement. To get a deeper insight into the molecular mechanism, effects of ODN MT01 treatment on the expression level of Sp7, runx-2, collagen-I, osteoprotegerin (OPG) and RANK ligand (RANKL) were determined using quantitative real time PCR and Western blotting. Remarkably, the mRNA and protein expression levels of Sp7, runx-2, collagen-I and OPG were improved after ODN MT01 treatment. Meanwhile, the protein expression level of RANKL was dramatically decreased. These results suggested that ODN MT01 had a significant impact in facilitating osteogenic proliferation and activation, and provided a direct evidence for the notion that single strand ODN could regulate the balance of bone formation and resorption, and thus was of great potential in the rebuilding of alveolar bone.
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Affiliation(s)
- Zhiyuan Feng
- Department of Orthodontics, School of Stomatology, Jilin University, 1500 Qinghua Road, Changchun 130021, China; E-Mails: (Z.F.); (J.W.)
| | - Yuqin Shen
- Department of Periodontal, School of Stomatology, Jilin University, 1500 Qinghua Road, Changchun 130021, China; E-Mail:
| | - Liying Wang
- Department of Molecular Biology, College of Basic Medicine, Jilin University, Changchun 130021, China; E-Mail:
| | - Lin Cheng
- Department of Oral Cavity, The Second Affiliated Hospital of Shanxi Medical University, 382 Wuyi Road, Taiyuan 030001, China; E-Mail:
| | - Jing Wang
- Department of Orthodontics, School of Stomatology, Jilin University, 1500 Qinghua Road, Changchun 130021, China; E-Mails: (Z.F.); (J.W.)
| | - Quanshun Li
- Key Laboratory for Molecular Enzymology and Engineering of Ministry of Education, Jilin University, 2699 Qianjin Road, Changchun 130021, China; E-Mail:
| | - Wei Shi
- Key Laboratory for Molecular Enzymology and Engineering of Ministry of Education, Jilin University, 2699 Qianjin Road, Changchun 130021, China; E-Mail:
| | - Xinhua Sun
- Department of Orthodontics, School of Stomatology, Jilin University, 1500 Qinghua Road, Changchun 130021, China; E-Mails: (Z.F.); (J.W.)
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Kajiya M, Giro G, Taubman MA, Han X, Mayer MPA, Kawai T. Role of periodontal pathogenic bacteria in RANKL-mediated bone destruction in periodontal disease. J Oral Microbiol 2010; 2. [PMID: 21523224 PMCID: PMC3084575 DOI: 10.3402/jom.v2i0.5532] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2010] [Revised: 09/14/2010] [Accepted: 10/11/2010] [Indexed: 11/18/2022] Open
Abstract
Accumulated lines of evidence suggest that hyperimmune responses to periodontal bacteria result in the destruction of periodontal connective tissue and alveolar bone. The etiological roles of periodontal bacteria in the onset and progression of periodontal disease (PD) are well documented. However, the mechanism underlying the engagement of periodontal bacteria in RANKL-mediated alveolar bone resorption remains unclear. Therefore, this review article addresses three critical subjects. First, we discuss earlier studies of immune intervention, ultimately leading to the identification of bacteria-reactive lymphocytes as the cellular source of osteoclast-induction factor lymphokine (now called RANKL) in the context of periodontal bone resorption. Next, we consider (1) the effects of periodontal bacteria on RANKL production from a variety of adaptive immune effector cells, as well as fibroblasts, in inflamed periodontal tissue and (2) the bifunctional roles (upregulation vs. downregulation) of LPS produced from periodontal bacteria in a RANKL-induced osteoclast-signal pathway. Future studies in these two areas could lead to new therapeutic approaches for the management of PD by down-modulating RANKL production and/or RANKL-mediated osteoclastogenesis in the context of host immune responses against periodontal pathogenic bacteria.
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Affiliation(s)
- Mikihito Kajiya
- Department of Immunology, The Forsyth Institute, Boston, MA, USA
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Chang JH, Chang EJ, Kim HH, Kim SK. Enhanced inhibitory effects of a novel CpG motif on osteoclast differentiation via TREM-2 down-regulation. Biochem Biophys Res Commun 2009; 389:28-33. [PMID: 19698700 DOI: 10.1016/j.bbrc.2009.08.080] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2009] [Accepted: 08/13/2009] [Indexed: 11/19/2022]
Abstract
Recognition of oligodeoxynucleotides containing CpG motifs (CpG-ODNs) by toll-like receptor 9 (TLR9) inhibits RANKL-induced osteoclastogenesis from precursors. This inhibitory effect suggests the possibility of using this strategy to block pathological bone loss. However, the enhancing effect of CpG-ODNs on OC formation from RANKL-primed pre-osteoclasts (pOCs) has hampered their clinical use. In this report, we developed a CpG-KSK13 oligonucleotide with an alternative CpG motif, and tested its effect on osteoclastogenesis in comparison with previously used murine CpG motif (CpG-1826) or human CpG motif (CpG-2006) oligonucleotides. Murine CpG-1826 inhibited RANKL-induced OC formation from BMMs but not from RANKL-primed pOCs, while CpG-KSK13 treatment strongly inhibited OC formation from both BMM and primed pOC cells. CpG-KSK13 also showed a potent inhibitory effect on human OC differentiation using peripheral blood mononuclear cells (PBMCs), which was in contrast to the species-specific response of murine CpG-1826 or human CpG-2006. Moreover, CpG-KSK13 effectively inhibited NFATc1 activity, but not NF-kappaB or AP-1 activity, and decreased TREM-2 promoter activity and subsequent surface expression of the TREM-2 protein induced by M-CSF and RANKL. These results demonstrate that the recognition of CpG-KSK13 via TLR9 inhibits osteoclastogenesis by down-regulating TREM-2 expression. Thus, our findings provide evidence for the potential use of CpG-KSK13 as an anti-osteoclastogenic agent for human and for pre-clinical animals.
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Affiliation(s)
- Jae-Ho Chang
- Institute of Basic Medical Science, Wonju College of Medicine, Yonsei University, Wonju 220-710, South Korea
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Bar-Shavit Z. Taking a Toll on the bones: Regulation of bone metabolism by innate immune regulators. Autoimmunity 2009; 41:195-203. [DOI: 10.1080/08916930701694469] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Bar-Shavit Z. The osteoclast: a multinucleated, hematopoietic-origin, bone-resorbing osteoimmune cell. J Cell Biochem 2008; 102:1130-9. [PMID: 17955494 DOI: 10.1002/jcb.21553] [Citation(s) in RCA: 200] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Osteoclasts are multinucleated cells that derive from hematopoietic progenitors in the bone marrow which also give rise to monocytes in peripheral blood, and to the various types of tissue macrophages. Osteoclasts are formed by the fusion of precursor cells. They function in bone resorption and are therefore critical for normal skeletal development (growth and modeling), for the maintenance of its integrity throughout life, and for calcium metabolism (remodeling). To resorb bone, the osteoclasts attach to the bone matrix, their cytoskeleton reorganizes, and they assume polarized morphology and form ruffled borders to secrete acid and collagenolytic enzymes and a sealing zone to isolate the resorption site. Identification of the osteoclastogenesis inducer, the receptor activator of nuclear factor-kappaB ligand (RANKL), its cognate receptor RANK, and its decoy receptor osteoprotegerin (OPG), has contributed enormously to the dramatic advance in our understanding of the molecular mechanisms involved in osteoclast differentiation and activity. This explosion in osteoclast biology is reflected by the large number of reviews which appeared during the last decade. Here I will summarize the "classical" issues (origin, differentiation, and activity) in a general manner, and will discuss an untouched issue (multinucleation) and a relatively novel aspect of osteoclast biology (osteoimmunology).
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Affiliation(s)
- Zvi Bar-Shavit
- The Hubert H. Humphrey Center for Experimental Medicine and Cancer Research, Hebrew University Faculty of Medicine, Jerusalem 91120, Israel.
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Amcheslavsky A, Bar-Shavit Z. Toll-like receptor 9 ligand blocks osteoclast differentiation through induction of phosphatase. J Bone Miner Res 2007; 22:1301-10. [PMID: 17488193 DOI: 10.1359/jbmr.070501] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
UNLABELLED CpG-ODN, in addition to stimulation of osteoclastogenic signals in early osteoclast precursors, also induces phosphatase, shifting the pattern of ERK phosphorylation from sustained to transient. This shift results in the degradation of c-fos, an essential molecule for osteoclast differentiation. Therefore, CpG-ODN blocks osteoclast differentiation. INTRODUCTION Activation of either Toll-like receptor 9 (TLR9) or RANK induces similar responses in osteoclast precursors. Paradoxically, activation of TLR9 results in inhibition of RANKL-induced osteoclastogenesis. MATERIALS AND METHODS We used bone marrow-derived osteoclast precursors. Analyses of signaling molecules phosphorylation were performed using Western blotting. Different levels of gene expression analyses were performed using RT-PCR, Northern, and run-on analyses (for RNA), and EMSA, Western, and pulse-chase experiments (for protein). Phosphatase activity was measured spectrophotometrically. RESULTS We found that RANKL and TLR9 ligand, oligodeoxynucleotides containing unmethylated CpG dinucleotides (CpG-ODN), induce sustained and transient extracellular signal-regulated kinase (ERK) phosphorylation, respectively. Furthermore, together they induce a transient phosphorylation of ERK. The duration of ERK phosphorylation is a key factor in determining induction of c-fos, a protein critical for osteoclastogenesis. Indeed, we found that CpG-ODN does not induce c-fos and inhibits its induction by RANKL by enhancing c-fos mRNA and protein degradation. Our observation that CpG-ODN, but not RANKL, induces the expression of the phosphatase PP2A suggests that CpG-ODN exerts its inhibitory activity by induction of ERK dephosphorylation. Moreover, together with the phosphatase inhibitor okadaic acid, CpG-ODN induces sustained ERK phosphorylation and c-fos expression. CONCLUSIONS Our findings suggest that the increased rate of c-fos degradation by the TLR9 ligand mediates the inhibition of RANKL-induced osteoclast differentiation. The TLR9 ligand, through induction of dephosphorylation, prevents the sustained ERK phosphorylation needed for maintaining high c-fos levels that are essential for osteoclast differentiation.
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Affiliation(s)
- Alla Amcheslavsky
- The Hubert H. Humphrey Center for Experimental Medicine and Cancer Research, The Hebrew University Faculty of Medicine, Jerusalem, Israel
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Amcheslavsky A, Bar-Shavit Z. Interleukin (IL)-12 mediates the anti-osteoclastogenic activity of CpG-oligodeoxynucleotides. J Cell Physiol 2006; 207:244-50. [PMID: 16402377 DOI: 10.1002/jcp.20563] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Bacterial DNA activates the innate immune system via interactions with Toll-like receptor 9 (TLR9). This receptor recognizes CpG-oligodeoxynucleotides (CpG-ODNs) mimicking the CpG dinucleotides in certain sequence contexts characterizing this DNA. Most studies have shown increased osteoclast differentiation by TLR ligands. We found that activation of TLRs (specifically TLR4 and TLR9) in early osteoclast precursors results in inhibition of receptor activator of NF-kappaB ligand (RANKL)-induced osteoclast differentiation. Our objective is to identify the mechanism leading to this inhibitory effect of a TLR ligand. Since both RANKL-RANK and CpG-ODN-TLR9 interactions result in NF-kappaB activation, p38 and ERK phosphorylation, and TNF-alpha synthesis (all implicated in osteoclastogenesis), we hypothesized that CpG-ODN (but not RANKL) in addition induces the synthesis of an anti-osteoclastogenic factor. Control osteoclast precursors, and cells treated with RANKL, CpG-ODN, or their combination were studied using DNA arrays (GEArray Q Series Mouse NF-kappaB Signaling Pathway Gene Array, MM-016, SuperArray). We found a marked increase in the mRNA levels of the osteoclastogenesis inhibitor interleukin-12 (IL-12) in osteoclast precursors treated with CpG-ODN and CpG-ODN + RANKL. Northern and Western analyses, together with ELISA, confirmed the DNA array studies. In correlation with these findings, IL-12 inhibited RANKL-induced osteoclast differentiation and specific anti-IL-12-antibodies inhibited the anti-osteoclastogenic effect of CpG-ODN. In conclusion, activation of TLR9 by its ligand, CpG-ODN, results in synthesis and release of IL-12 opposing RANKL-induced osteoclast differentiation.
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Affiliation(s)
- Alla Amcheslavsky
- The Hubert H. Humphrey Center for Experimental Medicine and Cancer Research, The Hebrew University Faculty of Medicine, Jerusalem, Israel
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