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Chen Z, Akanbi F, Lucas DR, Walton DM, Benavides E, Soki FN, Siegel GW, McCauley LK, Clines GA. A skeleton in a huff: insights in etiologies of osteosclerosis. J Bone Miner Res 2024; 39:79-84. [PMID: 38477819 DOI: 10.1093/jbmr/zjad021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Revised: 12/12/2023] [Accepted: 12/15/2023] [Indexed: 03/14/2024]
Abstract
A 30-yr-old man developed right lower leg pain and a palpable solid mass. Radiographic imaging revealed a periosteal reaction with an exostotic mass arising from the right distal fibula. Generalized skeletal osteosclerosis with periosteal reaction was discovered on a radiographic skeletal survey. A biopsy of the right fibular mass revealed reactive woven bone. The patient was referred to a metabolic bone disease clinic, where laboratory values were consistent with secondary hyperparathyroidism and increased bone turnover. A DXA bone density scan revealed high bone density, with an L1-4 spine Z-score of +9.3, a left femoral neck Z-score of +8.5, and a total hip Z-score of +6.5. A dental exam revealed generalized gingival inflammation, teeth mobility, generalized horizontal alveolar bone loss and widening of the periodontal ligament space, increased bone density around the teeth, and thickening of the radicular lamina dura. An extensive evaluation was performed, with the result of a single test revealing the diagnosis. The differential diagnoses of osteosclerosis affecting the skeleton, teeth, and oral cavity are discussed.
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Affiliation(s)
- Zhaozhao Chen
- Department of Periodontics & Oral Medicine, University of Michigan School of Dentistry, Ann Arbor, MI, United States
| | - Folake Akanbi
- Department of Internal Medicine, University of Michigan School of Medicine, Ann Arbor, MI, United States
| | - David R Lucas
- Department of Pathology, University of Michigan School of Medicine, Ann Arbor, MI, United States
| | - David M Walton
- Department of Orthopaedic Surgery, University of Michigan School of Medicine, Ann Arbor, MI, United States
| | - Erika Benavides
- Department of Periodontics & Oral Medicine, University of Michigan School of Dentistry, Ann Arbor, MI, United States
| | - Fabiana N Soki
- Department of Periodontics & Oral Medicine, University of Michigan School of Dentistry, Ann Arbor, MI, United States
| | - Geoffrey W Siegel
- Department of Orthopaedic Surgery, University of Michigan School of Medicine, Ann Arbor, MI, United States
| | - Laurie K McCauley
- Department of Periodontics & Oral Medicine, University of Michigan School of Dentistry, Ann Arbor, MI, United States
- Department of Pathology, University of Michigan School of Medicine, Ann Arbor, MI, United States
| | - Gregory A Clines
- Department of Internal Medicine, University of Michigan School of Medicine, Ann Arbor, MI, United States
- Veterans Affairs Medical Center, Ann Arbor, MI, United States
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2
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Lv Y, Wang W, Yao L, He J, Bai G, Lin C, Tu C. Sodium Fluoride and Sulfur Dioxide Derivatives Induce TGF-β1-Mediated NBCe1 Downregulation Causing Acid-Base Disorder of LS8 Cells. Biol Trace Elem Res 2023; 201:828-842. [PMID: 35304687 DOI: 10.1007/s12011-022-03169-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Accepted: 02/16/2022] [Indexed: 01/25/2023]
Abstract
The aim of the present work was to assess whether the combination of sodium fluoride (NaF) and sulfur dioxide derivatives (SO2 derivatives) affects the expression of the electrogenic sodium bicarbonate cotransporter NBCe1 (SLC4A4), triggering an acid-base imbalance during enamel development, leading to enamel damage. LS8 cells was taken as the research objects and fluorescent probes, quantitative real-time polymerase chain reaction (qRT-PCR), western blot, and factorial analysis were used to clarify the nature of the fluoro-sulfur interaction and the potential signaling pathway involved in the regulation of NBCe1. The results showed that exposure to fluoride or SO2 derivatives resulted in an acid-base imbalance, and these changes were accompanied by inhibited expression of NBCe1 and TGF-β1; these effects were more significant after fluoride exposure as compared to exposure to SO2 derivatives. Interestingly, in most cases, the toxic effects during combined exposure were significantly reduced compared to the effects observed with fluoride or sulfur dioxide derivatives alone. The results also indicated that activation of TGF-β1 signaling significantly upregulated the expression of NBCe1, and this effect was suppressed after the Smad, ERK, and JNK signals were blocked. Furthermore, fluoride and SO2 derivative-dependent NBCe1 regulation was found to require TGF-β1. In conclusion, this study indicates that the combined effect of fluorine and sulfur on LS8 cells is mainly antagonistic. TGF-β1 may regulate NBCe1 and may participate in the occurrence of dental fluorosis through the classic TGF-β1/Smad pathway and the unconventional ERK and JNK pathways.
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Affiliation(s)
- Ying Lv
- School of Public Health, the key Laboratory of Environmental Pollution Monitoring and Disease Control, Ministry of Education, Guizhou Medical University, Guizhou, China
| | - Wentai Wang
- School of Public Health, the key Laboratory of Environmental Pollution Monitoring and Disease Control, Ministry of Education, Guizhou Medical University, Guizhou, China
| | - Lili Yao
- School of Public Health, the key Laboratory of Environmental Pollution Monitoring and Disease Control, Ministry of Education, Guizhou Medical University, Guizhou, China
| | - Jiaojiao He
- School of Public Health, the key Laboratory of Environmental Pollution Monitoring and Disease Control, Ministry of Education, Guizhou Medical University, Guizhou, China
| | - Guohui Bai
- Key Laboratory of Oral Disease Research, School of Stomatology, Zunyi Medical University, Zunyi, China
| | - Changhu Lin
- School of Public Health, the key Laboratory of Environmental Pollution Monitoring and Disease Control, Ministry of Education, Guizhou Medical University, Guizhou, China
| | - Chenglong Tu
- School of Public Health, the key Laboratory of Environmental Pollution Monitoring and Disease Control, Ministry of Education, Guizhou Medical University, Guizhou, China.
- The Toxicity Testing Center of Guizhou Medical University, Guizhou Medical University, Guizhou, China.
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3
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Wang X, Tewari N, Sato F, Tanimoto K, Thangavelu L, Makishima M, Bhawal UK. Biphasic Functions of Sodium Fluoride (NaF) in Soft and in Hard Periodontal Tissues. Int J Mol Sci 2022; 23:ijms23020962. [PMID: 35055148 PMCID: PMC8780524 DOI: 10.3390/ijms23020962] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 01/12/2022] [Accepted: 01/13/2022] [Indexed: 02/04/2023] Open
Abstract
Sodium fluoride (NaF) is widely used in clinical dentistry. However, the administration of high or low concentrations of NaF has various functions in different tissues. Understanding the mechanisms of the different effects of NaF will help to optimize its use in clinical applications. Studies of NaF and epithelial cells, osteoblasts, osteoclasts, and periodontal cells have suggested the significant roles of fluoride treatment. In this review, we summarize recent studies on the biphasic functions of NaF that are related to both soft and hard periodontal tissues, multiple diseases, and clinical dentistry.
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Affiliation(s)
- Xingzhi Wang
- Department of Biochemistry, Nihon University School of Medicine, Tokyo 173-8610, Japan;
| | - Nitesh Tewari
- Centre for Dental Education and Research, Division of Pedodontics and Preventive Dentistry, All India Institute of Medical Sciences, New Delhi 110029, India;
| | - Fuyuki Sato
- Shizuoka Cancer Center, Pathology Division, Shizuoka 411-8777, Japan;
| | - Keiji Tanimoto
- Department of Translational Cancer Research, Research Institute for Radiation Biology and Medicine, Hiroshima University, Hiroshima 734-8553, Japan;
| | - Lakshmi Thangavelu
- Center for Transdisciplinary Research, Department of Pharmacology, Saveetha Dental College, Saveetha Institute of Medical and Technical Sciences, Chennai 600077, India;
| | - Makoto Makishima
- Department of Biochemistry, Nihon University School of Medicine, Tokyo 173-8610, Japan;
- Correspondence: (M.M.); (U.K.B.)
| | - Ujjal K. Bhawal
- Center for Transdisciplinary Research, Department of Pharmacology, Saveetha Dental College, Saveetha Institute of Medical and Technical Sciences, Chennai 600077, India;
- Department of Biochemistry and Molecular Biology, Nihon University School of Dentistry at Matsudo, Chiba 271-8587, Japan
- Correspondence: (M.M.); (U.K.B.)
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Tobeiha M, Rajabi A, Raisi A, Mohajeri M, Yazdi SM, Davoodvandi A, Aslanbeigi F, Vaziri M, Hamblin MR, Mirzaei H. Potential of natural products in osteosarcoma treatment: Focus on molecular mechanisms. Biomed Pharmacother 2021; 144:112257. [PMID: 34688081 DOI: 10.1016/j.biopha.2021.112257] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Revised: 09/21/2021] [Accepted: 09/26/2021] [Indexed: 02/07/2023] Open
Abstract
Osteosarcoma is the most frequent type of bone cancer found in children and adolescents, and commonly arises in the metaphyseal region of tubular long bones. Standard therapeutic approaches, such as surgery, chemotherapy, and radiation therapy, are used in the management of osteosarcoma. In recent years, the mortality rate of osteosarcoma has decreased due to advances in treatment methods. Today, the scientific community is investigating the use of different naturally derived active principles against various types of cancer. Natural bioactive compounds can function against cancer cells in two ways. Firstly they can act as classical cytotoxic compounds by non-specifically affecting macromolecules, such as DNA, enzymes, and microtubules, which are also expressed in normal proliferating cells, but to a greater extent by cancer cells. Secondly, they can act against oncogenic signal transduction pathways, many of which are activated in cancer cells. Some bioactive plant-derived agents are gaining increasing attention because of their anti-cancer properties. Moreover, some naturally-derived compounds can significantly promote the effectiveness of standard chemotherapy drugs, and in certain cases are able to ameliorate drug-induced adverse effects caused by chemotherapy. In the present review we summarize the effects of various naturally-occurring bioactive compounds against osteosarcoma.
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Affiliation(s)
- Mohammad Tobeiha
- School of Medicine, Kashan University of Medical Sciences, Kashan, Iran; Student Research Committee, Kashan University of Medical Sciences, Kashan, Iran
| | - Ali Rajabi
- School of Medicine, Kashan University of Medical Sciences, Kashan, Iran; Student Research Committee, Kashan University of Medical Sciences, Kashan, Iran
| | - Arash Raisi
- School of Medicine, Kashan University of Medical Sciences, Kashan, Iran; Student Research Committee, Kashan University of Medical Sciences, Kashan, Iran
| | - Mahshad Mohajeri
- School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | | | - Amirhossein Davoodvandi
- Student Research Committee, Kashan University of Medical Sciences, Kashan, Iran; Cancer Immunology Project (CIP), Universal Scientific Education and Research Network (USERN), Tehran, Iran
| | - Fatemeh Aslanbeigi
- School of Medicine, Kashan University of Medical Sciences, Kashan, Iran; Student Research Committee, Kashan University of Medical Sciences, Kashan, Iran
| | - MohamadSadegh Vaziri
- Student Research Committee, Hormozgan University of Medical Sciences, Bandar Abbas, Iran.
| | - Michael R Hamblin
- Laser Research Centre, Faculty of Health Science, University of Johannesburg, Doornfontein 2028, South Africa.
| | - Hamed Mirzaei
- Research Center for Biochemistry and Nutrition in Metabolic Diseases, Institute for Basic Sciences, Kashan University of Medical Sciences, Kashan, Iran.
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5
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Liu J, Dai Q, Weir MD, Schneider A, Zhang C, Hack GD, Oates TW, Zhang K, Li A, Xu HHK. Biocompatible Nanocomposite Enhanced Osteogenic and Cementogenic Differentiation of Periodontal Ligament Stem Cells In Vitro for Periodontal Regeneration. MATERIALS 2020; 13:ma13214951. [PMID: 33158111 PMCID: PMC7663634 DOI: 10.3390/ma13214951] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/25/2020] [Revised: 10/28/2020] [Accepted: 10/31/2020] [Indexed: 12/20/2022]
Abstract
Decays in the roots of teeth is prevalent in seniors as people live longer and retain more of their teeth to an old age, especially in patients with periodontal disease and gingival recession. The objectives of this study were to develop a biocompatible nanocomposite with nano-sized calcium fluoride particles (Nano-CaF2), and to investigate for the first time the effects on osteogenic and cementogenic induction of periodontal ligament stem cells (hPDLSCs) from human donors.Nano-CaF2 particles with a mean particle size of 53 nm were produced via a spray-drying machine.Nano-CaF2 was mingled into the composite at 0%, 10%, 15% and 20% by mass. Flexural strength (160 ± 10) MPa, elastic modulus (11.0 ± 0.5) GPa, and hardness (0.58 ± 0.03) GPa for Nano-CaF2 composite exceeded those of a commercial dental composite (p < 0.05). Calcium (Ca) and fluoride (F) ions were released steadily from the composite. Osteogenic genes were elevated for hPDLSCs growing on 20% Nano-CaF2. Alkaline phosphatase (ALP) peaked at 14 days. Collagen type 1 (COL1), runt-related transcription factor 2 (RUNX2) and osteopontin (OPN) peaked at 21 days. Cementogenic genes were also enhanced on 20% Nano-CaF2 composite, promoting cementum adherence protein (CAP), cementum protein 1 (CEMP1) and bone sialoprotein (BSP) expressions (p < 0.05). At 7, 14 and 21 days, the ALP activity of hPDLSCs on 20% Nano-CaF2 composite was 57-fold, 78-fold, and 55-fold greater than those of control, respectively (p < 0.05). Bone mineral secretion by hPDLSCs on 20% Nano-CaF2 composite was 2-fold that of control (p < 0.05). In conclusion, the novel Nano-CaF2 composite was biocompatible and supported hPDLSCs. Nano-CaF2 composite is promising to fill tooth root cavities and release Ca and F ions to enhance osteogenic and cementogenic induction of hPDLSCs and promote periodontium regeneration.
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Affiliation(s)
- Jin Liu
- Key Laboratory of Shannxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi’an Jiaotong University, Xi’an 710004, China; (J.L.); (Q.D.)
- Clinical Research Center of Shannxi Province for Dental and Maxillofacial Diseases, College of Stomatology, Xi’an Jiaotong University, Xi’an 710004, China
- Department of Advanced Oral Sciences and Therapeutics, University of Maryland Dental School, Baltimore, MD 21201, USA; (M.D.W.); (C.Z.); (G.D.H.); (T.W.O.)
| | - Quan Dai
- Key Laboratory of Shannxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi’an Jiaotong University, Xi’an 710004, China; (J.L.); (Q.D.)
- Clinical Research Center of Shannxi Province for Dental and Maxillofacial Diseases, College of Stomatology, Xi’an Jiaotong University, Xi’an 710004, China
- Department of Advanced Oral Sciences and Therapeutics, University of Maryland Dental School, Baltimore, MD 21201, USA; (M.D.W.); (C.Z.); (G.D.H.); (T.W.O.)
| | - Michael D. Weir
- Department of Advanced Oral Sciences and Therapeutics, University of Maryland Dental School, Baltimore, MD 21201, USA; (M.D.W.); (C.Z.); (G.D.H.); (T.W.O.)
| | - Abraham Schneider
- Department of Oncology and Diagnostic Sciences, University of Maryland School of Dentistry, Baltimore, MD 21201, USA;
- Member, Marlene and Stewart Greenebaum Cancer Center, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Charles Zhang
- Department of Advanced Oral Sciences and Therapeutics, University of Maryland Dental School, Baltimore, MD 21201, USA; (M.D.W.); (C.Z.); (G.D.H.); (T.W.O.)
| | - Gary D. Hack
- Department of Advanced Oral Sciences and Therapeutics, University of Maryland Dental School, Baltimore, MD 21201, USA; (M.D.W.); (C.Z.); (G.D.H.); (T.W.O.)
| | - Thomas W. Oates
- Department of Advanced Oral Sciences and Therapeutics, University of Maryland Dental School, Baltimore, MD 21201, USA; (M.D.W.); (C.Z.); (G.D.H.); (T.W.O.)
| | - Ke Zhang
- Department of Orthodontics, School of Stomatology, Capital Medical University, Beijing 100069, China
- Correspondence: (K.Z.); (A.L.); (H.H.K.X.); Tel.: +86-010-5709-9222 (K.Z.); +86-029-8721-6572 (A.L.); +86-44-3562-1295 (H.H.K.X.)
| | - Ang Li
- Key Laboratory of Shannxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi’an Jiaotong University, Xi’an 710004, China; (J.L.); (Q.D.)
- Clinical Research Center of Shannxi Province for Dental and Maxillofacial Diseases, College of Stomatology, Xi’an Jiaotong University, Xi’an 710004, China
- Correspondence: (K.Z.); (A.L.); (H.H.K.X.); Tel.: +86-010-5709-9222 (K.Z.); +86-029-8721-6572 (A.L.); +86-44-3562-1295 (H.H.K.X.)
| | - Hockin H. K. Xu
- Department of Advanced Oral Sciences and Therapeutics, University of Maryland Dental School, Baltimore, MD 21201, USA; (M.D.W.); (C.Z.); (G.D.H.); (T.W.O.)
- Member, Marlene and Stewart Greenebaum Cancer Center, University of Maryland School of Medicine, Baltimore, MD 21201, USA
- Center for Stem Cell Biology & Regenerative Medicine, University of Maryland School of Medicine, Baltimore, MD 21201, USA
- Correspondence: (K.Z.); (A.L.); (H.H.K.X.); Tel.: +86-010-5709-9222 (K.Z.); +86-029-8721-6572 (A.L.); +86-44-3562-1295 (H.H.K.X.)
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6
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Sun J, Wu T, Fan Q, Hu Q, Shi B. Comparative study of hydroxyapatite, fluor-hydroxyapatite and Si-substituted hydroxyapatite nanoparticles on osteogenic, osteoclastic and antibacterial ability. RSC Adv 2019; 9:16106-16118. [PMID: 35521374 PMCID: PMC9064369 DOI: 10.1039/c9ra00839j] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Accepted: 03/21/2019] [Indexed: 12/30/2022] Open
Abstract
This study compared the effects of hydroxyapatite (HA), fluor-hydroxyapatite (FHA) and Si-substituted hydroxyapatite (SiHA) on osteogenic differentiation, osteoclastic activity and antibacterial properties. HA, FHA and SiHA were prepared via a sol-gel reaction and characterized by scanning electron microscopic analysis (SEM), transmission electron microscopic analysis (TEM), and X-ray photoelectron spectrometry. Cell proliferation was evaluated using an MTT assay and cytoskeletal morphology was observed by fluorescence microscopy. Osteogenic differentiation was evaluated using alkaline phosphatase activity and Alizarin red staining. Quantitative real-time PCR was used to evaluate the mRNA expression of runt-related transcription factor 2 (Runx2) and osteopontin (OPN). New bone formation was tested using μCT, haematoxylin and eosin staining and TRAP staining. The antibacterial actions against Porphyromonas gingivalis (P. g) were evaluated through plate counting and live-dead bacterial staining. The results demonstrated that HA, FHA and SiHA can promote proliferation of bone mesenchymal stem cells (BMSCs). ALP activity in FHA extract with a concentration of 625 μg mL-1 was the highest after 14 days osteogenic induction; similar results were observed for Runx2 and OPN mRNA expression. HA, FHA and SiHA decreased trabecular space in bone defects, but FHA reduced osteoclastic activity and inhibited P. g growth. In conclusion, FHA can promote osteogenic activity, reduce osteoclastic activity and enhance antibacterial effects.
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Affiliation(s)
- Jing Sun
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST), Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology, Wuhan University Wuhan 430079 CN China
| | - Tao Wu
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST), Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology, Wuhan University Wuhan 430079 CN China
| | - Qihang Fan
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST), Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology, Wuhan University Wuhan 430079 CN China
| | - Qing Hu
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST), Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology, Wuhan University Wuhan 430079 CN China
| | - Bin Shi
- The State Key Laboratory Breeding Base of Basic Science of Stomatology (Hubei-MOST), Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology, Wuhan University Wuhan 430079 CN China
- Department of Dental Implantology, School and Hospital of Stomatology, Wuhan University China
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7
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Wang L, Zhu Y, Wang D. High-Dose Fluoride Induces Apoptosis and Inhibits Ameloblastin Secretion in Primary Rat Ameloblast. Biol Trace Elem Res 2016; 174:402-409. [PMID: 27193486 DOI: 10.1007/s12011-016-0738-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/19/2016] [Accepted: 05/09/2016] [Indexed: 12/13/2022]
Abstract
The objectives of this study are to establish the in vitro culture system for rat primary ameloblast and to investigate the effects of fluoride on cell viability, apoptosis, and ameloblastin (AMBN) secretion of primary rat ameloblast in vitro. Ameloblast was isolated from the tooth germ of the maxillomandibular molar and cultured in vitro. Cells were treated with NaF at 0.4, 0.8, 1.6, 3.2, and 6.4 mM for 24, 48, and 72 h, respectively. Cell viability was measured by MTT assay and apoptosis was tested by flow cytometry. The activation of Fas ligand (FasL)/Fas pathway was detected using immunoblotting for FasL, Fas, cleaved caspase-8, cleaved caspase-3, and cleaved PARP. Secretion of AMBN in culture medium was measured using ELISA. Primary rat ameloblast was successfully isolated and cultured. The effects of low-dose fluoride on cell viability were bi-phasic, while high-dose fluoride resulted in decreased cell viability uniformly. Fluoride induced ameloblast apoptosis via activation of FasL/Fas signaling pathway and diminished secretion of AMBN by ameloblast. Fluoride could decrease ameloblast viability, induce ameloblast apoptosis via activating FasL/Fas signaling pathway, and reduce AMBN secretion.
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Affiliation(s)
- Lin Wang
- Department of Stomatology, Xi'an Medical University, No. 1, XinWang Road, WeiYang District, Xi'an, 710021, China.
| | - Yong Zhu
- Department of Stomatology, Xi'an Medical University, No. 1, XinWang Road, WeiYang District, Xi'an, 710021, China
| | - Danyang Wang
- Department of Stomatology, Xi'an Medical University, No. 1, XinWang Road, WeiYang District, Xi'an, 710021, China
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Lee HJ, Arikawa K. Influence of Low Level Sodium Fluoride on Expression of IGF-1 and IGF-2 Protein in Experimental Type 2 Diabetes with Periodontitis Model. J HARD TISSUE BIOL 2015. [DOI: 10.2485/jhtb.24.319] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- Hye-Jin Lee
- Department of Dental Hygiene, Howon University
| | - Kazumune Arikawa
- Department of Preventive and Public Oral Health, Nihon University School of Dentistry at Matsudo
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Ohno M, Kimoto K, Toyoda T, Kawata K, Arakawa H. Fluoride-Treated Bio-Resorbable Synthetic Hydroxyapatite Promotes Proliferation and Differentiation of Human Osteoblastic MG-63 Cells. J ORAL IMPLANTOL 2013; 39:154-60. [DOI: 10.1563/aaid-joi-d-10-00175] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
When resorbable hydroxyapatite (HA) granules, which are used as a bone supplement material, were treated in neutral 4% sodium fluoride (NaF) solution, formation of a reactant resembling calcium fluoride was observed on the surface of the granules. Immediate and slow release of fluoride from fluoridated HA (HA+F) granules was observed after immersion in culture fluid, and the concentration increased over time to 1.25 ± 0.05 ppm F at 0.5 hours, 1.57 ± 0.12 ppm F at 24 hours, and 1.73 ± 0.15 ppm F at 48 hours. On invasion assay, migration of human osteoblast-like MG-63 cells exposed to the released fluoride was confirmed in comparison to the cells incubated with a nonfluoridated control sample (P < .01). In addition, fluoride added to the medium increased MG-63 cell proliferation in a manner dependent on fluoride concentrations up to 2.0 ppm (P < .05). At 5.0 ppm, however, fluoride significantly inhibited cell proliferation (P < .005). Activity of the osteogenic differentiation marker, alkaline phosphatase (ALP), also increased with fluoride after exposure for 1 week, increasing significantly at 1.0 ppm (P < .05). The promotion of MG-63 cell migration and proliferation, as well as increased ALP activity, suggested that fluoride released from the surface of resorbable HA granules, which were fluoridated by prior treatment with neutral 4% NaF solution, can provide a superb method to supply fluoride and promote osteogenic cell differentiation.
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Affiliation(s)
- Motofumi Ohno
- Division of Oral Health, Department of Health Science, Kanagawa Dental College, Yokosuka, Japan
| | - Kazunari Kimoto
- Division of Oral Health, Department of Health Science, Kanagawa Dental College, Yokosuka, Japan
| | | | - Kazushige Kawata
- Division of Oral Health, Department of Health Science, Kanagawa Dental College, Yokosuka, Japan
| | - Hirohisa Arakawa
- Division of Oral Health, Department of Health Science, Kanagawa Dental College, Yokosuka, Japan
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10
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Fluoride inhibits the response of bone cells to mechanical loading. Odontology 2011; 99:112-8. [DOI: 10.1007/s10266-011-0013-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2010] [Accepted: 12/03/2010] [Indexed: 12/22/2022]
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11
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Arakawa Y, Bhawal UK, Ikoma T, Kimoto K, Kuroha K, Kubota T, Hamada N, Kubota E, Arakawa H. Low concentration fluoride stimulates cell motility of epithelial cells in vitro. Biomed Res 2009; 30:271-7. [DOI: 10.2220/biomedres.30.271] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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12
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Xu H, Wang CH, Zhao ZT, Zhang WB, Li GS. Role of oxidative stress in osteoblasts exposed to sodium fluoride. Biol Trace Elem Res 2008; 123:109-15. [PMID: 18193172 DOI: 10.1007/s12011-007-8082-7] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/10/2007] [Revised: 10/25/2007] [Accepted: 11/27/2007] [Indexed: 11/24/2022]
Abstract
We investigated the relationship between oxidative stress and osteoblasts viability in osteoblasts exposed to various concentrations of fluoride in this study. Primary calvarial osteoblasts from neonatal Kunming mice were cultured and subcultured to the third generation. Osteoblasts were incubated with sodium fluoride (0, 0.5, 1, 2, 4, 8, 12, and 20 mgF(-)/L) for 24, 48, and 72 h. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) analysis showed cell viability significantly increased after osteoblasts exposed to low concentrations of fluoride (0.5 to approximately 2 mgF(-)/L) for 24 to approximately 72 h. Oxidative stress analysis showed that low concentration of fluoride excited lipid peroxidation in osteoblasts and increased activity of antioxidant enzymes in varying degrees. We demonstrated that changes of osteoblasts viability of the low-dose fluoride groups are different from those of high-dose fluoride groups; however, both low and high doses of fluoride caused active state of oxidative stress in osteoblasts, which suggesting that oxidative stress may be excited by the active osteoblasts viability induced by a low dose of fluoride.
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Affiliation(s)
- Hui Xu
- Institute of Endemic Diseases, Jilin University, Changchun, 130021, China.
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Qu WJ, Zhong DB, Wu PF, Wang JF, Han B. Sodium fluoride modulates caprine osteoblast proliferation and differentiation. J Bone Miner Metab 2008; 26:328-34. [PMID: 18600398 DOI: 10.1007/s00774-007-0832-2] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/05/2007] [Accepted: 12/02/2007] [Indexed: 11/29/2022]
Abstract
The cellular and molecular pathways of fluoride toxicity in osteoblasts are not very well understood. Therefore, the objective of the present study was to evaluate the effects of sodium fluoride (NaF) on caprine osteoblasts cultured in vitro. Caprine osteoblasts at 2.0 x 10(-4) cells/ml were incubated in vitro with NaF at 0, 10(-8), 10(-7), 10(-6), 10(-5), 10(-4), 5.0 x 10(-4), and 10(-3) M, and then proliferation, differentiation, apoptosis, calcification, and alkaline phosphatase activity were examined. Also, the effect of NaF on osteoblastic cell viability and the molecular events leading to apoptosis were determined. Electron microscopy revealed cytoplasmic and nuclear alterations in the ultrastructure of osteoblasts exposed to various NaF concentrations. A cell-based quantitative evaluation of the MTT assay showed that NaF at concentrations of 10(-8) to 10(-5) M promoted cell proliferation, whereas at 10(-4) to 10(-3) M it suppressed cell proliferation and induced apoptosis. Alkaline phosphatase (ALP) activity and mineralization ability increased in cells treated at 10(-8) to 10(-5) M with sodium versus the controls, but decreased at 5.0 x 10(-4) to 10(-3) M dosage. The highest incidence of early apoptotic cells and late apoptotic cells was reached (3.33% and 2.92%, respectively) under NaF concentration of 10(-4) M. In conclusion, results of this study indicated that NaF modulates osteoblast proliferation and differentiation in a dose-dependent manner and modified osteoblast metabolism bidirectionally, suggesting NaF may play a significant role in osteoblast physiology.
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Affiliation(s)
- Wei-Jie Qu
- College of Veterinary Medicine, China Agricultural University, 100094 Beijing, China
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14
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Wada K, Mizuno M, Komori T, Tamura M. Extracellular inorganic phosphate regulates Gibbon ape leukemia virus receptor-2/phosphate transporter mRNA expression in rat bone marrow stromal cells. J Cell Physiol 2003; 198:40-7. [PMID: 14584042 DOI: 10.1002/jcp.10383] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
In mammalian cells, several observations indicate not only that phosphate transport probably regulates local inorganic phosphate (Pi) concentration, but also that Pi affects normal cellular metabolism, which in turn regulates apoptosis and the process of mineralization. To elucidate how extracellular Pi regulates cellular functions of pre-osteoblastic cells, we investigated the expression of type III sodium (Na)-dependent Pi transporters in rat bone marrow stromal cells and ROB-C26 pre-osteoblastic cells. The mRNA expression level of gibbon ape leukemia virus receptor (Glvr)-2 was increased by the addition of Pi in rat bone marrow stromal cells, but not in ROB-C26 or normal rat kidney (NRK) cells. In contrast, the level of Glvr-1 mRNA was not altered by the addition of extracellular Pi in these cells. The induction of Glvr-2 mRNA by Pi was inhibited in the presence of cycloheximide (CHX). Moreover, mitogen-activated protein kinase (MEK) /extracellular-signal-regulated kinase (ERK) pathway inhibitors; U0126 (1.4-diamino-2, 3-dicyano-1, 4-bis [2-amino-phenylthio] butadiene) and PD98059 (2'-Amino-3'-methoxyflavone) inhibited inducible Glvr-2 mRNA expression, but p38 MEK inhibitor SB203580 [4-(4'-fluorophenyl)-2-(4'-methyl-sulfinylphenyl)-5-(4'pyridyl) imidazole] did not inhibit the induction of Glvr-2 mRNA expression, suggesting that extracellular Pi regulates de novo protein synthesis and MEK/ERK activity in rat bone marrow stromal cells, and through these, induction of Glvr-2 mRNA. Although Pi also induced osteopontin mRNA expression in rat bone marrow stromal cells but not in ROB-C26 and NRK cells, changes in cell viability with the addition of Pi were similar in both cell types. These data indicate that extracellular Pi regulates Glvr-2 mRNA expression, provide insights into possible mechanisms whereby Pi may regulate protein phosphorylation, and suggest a potential role for the Pi transporter in rat bone marrow stromal cells.
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Affiliation(s)
- Keinoshin Wada
- Division of Oral and Maxillofacial Surgery, Department of Organ Therapeutics, Graduate School of Medicine, Kobe University, Kobe, Japan
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15
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Abstract
Osteoporosis is a condition of increasing importance and prevalence in all parts of the world and particularly in Asia. Recent advances have led to the introduction of effective drugs that decrease bone resorption and stabilize bone mass. However, these drugs have been identified by serendipity rather than rational drug design and are not ideal because of limited bioavailability, mode of administration, or other unwanted effects. There is still a place for even more suitable and effective resorption inhibitors than those currently available. The more compelling need in this field is an acceptable drug that is anabolic for bone, that safely and acceptably increases bone mass and improves the disturbances in bone microarchitecture that characterize established and advanced osteoporosis. Possible approaches to identifying more effective resorption inhibitors and new anabolic agents are discussed.
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Affiliation(s)
- Gregory R Mundy
- Department of Medicine/Endocrinology, University of Texas Health Science Center, 7703 Floyd Curl Drive, San Antonio, Texas 78229-3900, USA.
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16
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Busby MG, Jeffcoat AR, Bloedon LT, Koch MA, Black T, Dix KJ, Heizer WD, Thomas BF, Hill JM, Crowell JA, Zeisel SH. Clinical characteristics and pharmacokinetics of purified soy isoflavones: single-dose administration to healthy men. Am J Clin Nutr 2002; 75:126-36. [PMID: 11756070 DOI: 10.1093/ajcn/75.1.126] [Citation(s) in RCA: 217] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Soy isoflavones are potential cancer chemoprevention treatments. OBJECTIVE We conducted safety studies of purified unconjugated genistein, daidzein, and glycitein, and defined pharmacokinetic parameters for their absorption and metabolism. DESIGN Thirty healthy men ingested a single dose of 1 of 2 isoflavone preparations purified from soy. The delivered doses of genistein (1, 2, 4, 8, or 16 mg/kg body wt) were higher than those previously administered to humans. Formulation A was composed of 90 +/- 5% genistein, 10% daidzein, and 1% glycitein. Formulation B was composed of 43% genistein, 21% daidzein, and 2% glycitein. RESULTS We observed no clinically significant behavioral or physical changes after treatment. We observed elevations in lipoprotein lipase and hypophosphatemia that were possibly related to the treatment but that were associated with no clinical toxicity. Considerable quantities of isoflavones were excreted in urine as conjugates. The terminal elimination rate, elimination half-life, area under the curve, maximum plasma concentration, apparent systemic clearance, and volume of distribution were estimated for genistein and daidzein. The mean elimination half-lives with both formulations were 3.2 h for free genistein and 4.2 h for free daidzein. The mean pseudo half-lives were 9.2 h for total genistein and 8.2 h for total daidzein. CONCLUSIONS Dietary supplements of purified unconjugated isoflavones administered to humans in single doses exceeding normal dietary intake manyfold resulted in minimal clinical toxicity. Genistein and daidzein (free and total) were rapidly cleared from plasma and excreted in urine.
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Affiliation(s)
- Marjorie G Busby
- Department of Nutrition, the School of Public Health, the School of Medicine, the University of North Carolina, Chapel Hill 27599-7400, USA
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17
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Affiliation(s)
- G R Mundy
- University of Texas Health Science Center, 7703 Floyd Curl Drive, San Antonio, Texas 78284-7877, USA.
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18
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Abstract
Fluoride is an effective anabolic agent to increase spinal bone density by increasing bone formation, and at therapeutically relevant (i.e., micromolar) concentrations, it stimulates bone cell proliferation and activities in vitro and in vivo. However, the fluoride therapy of osteoporosis has been controversial, in large part because of a lack of consistent antifracture efficacy. However, information regarding the molecular mechanism of action of fluoride may improve its optimum and correct usage and may disclose potential targets for the development of new second generation drugs that might have a better efficacy and safety profile. Accordingly, this review will address the molecular mechanisms of the osteogenic action of fluoride. In this regard, we and other workers have proposed two competing models, both of which involve the mitogen activated protein kinase (MAPK) mitogenic signal transduction pathway. Our model involves a fluoride inhibition of a unique fluoride-sensitive phosphotyrosine phosphatase (PTP) in osteoblasts, which results in a sustained increase in the tyrosine phosphorylation level of the key signaling proteins of the MAPK mitogenic transduction pathway, leading to the potentiation of the bone cell proliferation initiated by growth factors. The competing model proposes that fluoride acts in coordination with aluminum to form fluoroaluminate, which activates a pertussis toxin-sensitive Gi/o protein on bone cell membrane, leading to an activation of cellular protein tyrosine kinases (PTKs), which in turn leads to increases in the tyrosine phosphorylation of signaling proteins of the MAPK mitogenic signal transduction pathway, ultimately leading to a stimulation of cell proliferation. A benefit of our model, but not the other model, is that it accounts for all the unique properties of the osteogenic action of fluoride. These include the low effective fluoride dose, the skeletal tissue specificity, the requirement of PTK-activating growth factors, the sensitivity to changes in medium phosphate concentration, the preference for undifferentiated osteoblasts, and the involvement of the MAPK. Unlike fluoride, the mitogenic action of fluoroaluminate is not specific for skeletal cells. Moreover, the mitogenic action of fluoroaluminate shows several important, different characteristics than that of fluoride. Thus, it is likely that our model of a fluoride-sensitive PTP represents the actual molecular mechanism of the osteogenic action of fluoride.
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Affiliation(s)
- K H Lau
- Musculoskeletal Disease Center, Jerry L. Pettis Memorial V.A. Medical Center, Department of Medicine, Loma Linda University, California 92357, USA
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19
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Affiliation(s)
- J Caverzasio
- WHO Collaborating Center for Osteoporosis and Bone Diseases, Department of Internal Medicine, University Hospital, Geneva, Switzerland.
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20
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Jeschke M, Standke GJ, Scaronuscarona M. Fluoroaluminate induces activation and association of Src and Pyk2 tyrosine kinases in osteoblastic MC3T3-E1 cells. J Biol Chem 1998; 273:11354-61. [PMID: 9556630 DOI: 10.1074/jbc.273.18.11354] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Fluoride is known to increase bone mass in vivo, probably through stimulation of osteoblast proliferation; however, the mechanisms of fluoroaluminate action in osteoblasts have not yet been elucidated. We have previously shown that in osteoblastic MC3T3-E1 cells, fluoroaluminate stimulates G protein-mediated protein tyrosine phosphorylation (Scaronuscarona, M., Standke, G. J. R., Jeschke, M., and Rohner, D. (1997) Biochem. Biophys. Res. Commun. 235, 680-684). Although the Ser/Thr kinases Erk1, Erk2, and p70(S6K) were activated in response to fluoroaluminate, the identity of fluoroaluminate-activated tyrosine kinase(s) remained elusive. In this study, we show that in MC3T3-E1 cells, fluoroaluminate induces a 110-kDa tyrosine-phosphorylated protein that we identify as Pyk2, a cytoplasmic tyrosine kinase related to Fak (focal adhesion kinase). The tyrosine phosphorylation of Pyk2 increased in a dose- and time-dependent manner. The autophosphorylation activity of Pyk2 increased 3-fold and reached its maximum within 10 min of fluoroaluminate treatment. Fluoroaluminate also induced activation of Src and the association of Pyk2 with Src. The phosphorylation of Src-associated Pyk2 increased >20-fold in in vitro kinase assays, suggesting that Pyk2 is phosphorylated by Src. Although MC3T3-E1 cells express much more Fak than Pyk2, Src preferentially associated with Pyk2. In vitro, Pyk2 bound to the Src SH2 domain, suggesting that this interaction mediates the Src-Pyk2 association in cells. These data indicate that osteoblastic cells express Pyk2, which is tyrosine-phosphorylated and activated in response to G protein activation by fluoroaluminate, and that the mechanism of Pyk2 activation most likely involves Src. Thus, Src and Pyk2 are tyrosine kinases involved in G protein-mediated tyrosine phosphorylation in osteoblastic cells and may be important for the osteogenic action of fluoroaluminate.
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Affiliation(s)
- M Jeschke
- Research Bone Metabolism, Novartis Pharma AG, CH-4002 Basel, Switzerland
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21
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Hulley PA, Gordon F, Hough FS. Inhibition of mitogen-activated protein kinase activity and proliferation of an early osteoblast cell line (MBA 15.4) by dexamethasone: role of protein phosphatases. Endocrinology 1998; 139:2423-31. [PMID: 9564854 DOI: 10.1210/endo.139.5.6020] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Chronic glucocorticoid therapy causes rapid bone loss and clinical osteoporosis. We found that although the glucocorticoid, dexamethasone, stimulated osteoblast maturation, it also inhibited proliferation of a preosteoblastic cell line, MBA-15.4. The dexamethasone-induced decline in preosteoblast proliferation correlated with a 30-40% reduction in protein kinase C/TPA-stimulated mitogen-activated protein kinase (MAPK) activity. These steroid effects only became evident after 6-24 h treatment, implying that dexamethasone acts on de novo synthesis of proteins. Because MAPK is inactivated by dephosphorylation of tyrosine and threonine residues, cells were treated concomitantly for 24 h with dexamethasone and inhibitors of tyrosine (sodium orthovanadate) and/or serine/threonine phosphatases (sodium fluoride). MAPK activity and cell proliferation were restored when MBA-15.4 cells were treated with vanadate, suggesting that dexamethasone up-regulates tyrosine phosphatase activity. Inactivation of serine/threonine phosphatases with sodium fluoride had no effect. Inhibition of the PKA pathway (which is growth inhibitory in mature osteoblasts) with H-89 did not reverse the effects of dexamethasone. Pretreatment with dexamethasone inhibited both peak- and extended activation plateau-phases of MAPK activity. Both phases were fully restored by pretreatment with vanadate, implicating more than one tyrosine phosphatase. Cycloheximide, alone or in combination with dexamethasone, prevented drop-off from plateau to basal levels, suggesting that an inducible dual-specificity phosphatase regulates the plateau-phase. We conclude that dexamethasone may inhibit preosteoblast growth via a novel tyrosine phosphatase pathway.
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Affiliation(s)
- P A Hulley
- Department of Endocrinology and Metabolism, University of Stellenbosch Medical School, Tygerberg, Cape Town, South Africa.
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22
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Osteoblast Lineage. ACTA ACUST UNITED AC 1998. [DOI: 10.1016/s1569-2590(08)60131-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
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23
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Ammann P, Rizzoli R, Caverzasio J, Bonjour JP. Fluoride potentiates the osteogenic effects of IGF-I in aged ovariectomized rats. Bone 1998; 22:39-43. [PMID: 9437512 DOI: 10.1016/s8756-3282(97)00206-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The molecular mechanisms whereby fluoride stimulates osteogenic cell proliferation are not clearly established. However, fluoride has been shown to enhance the protein tyrosine phosphorylation of various constituents of intracellular signaling cascades in osteoblastic cells following stimulation of growth factor receptors such as the insulin-like growth factor-I (IGF-I) receptor. Such in vitro findings provided the rationale for testing whether the administration of fluoride could enhance IGF-I effects on bone mass in vivo. Adult ovariectomized osteopenic rats were treated with sodium fluoride at a dose of 6 mg/kg per day in drinking water for 8 weeks in association with IGF-I either at a dose of 2 mg/kg per day, which is capable of increasing bone mass, or at a lower dose without detectable skeletal effects. Bone mineral density (BMD) and content (BMC) were evaluated by dual-energy X-ray absorptiometry at the levels of the lumbar spine and proximal, midshaft, and total tibia before and after 8 weeks of treatment. During this period, fluoride alone did not significantly influence BMD/BMC at any skeletal site. However, it potentiated the effect of the higher dose of IGF-I on bone mass at the level of the proximal tibia. When administered in combination with the lower dose of IGF-I, which per se did not modify bone mass, it appeared to sensitize tibial bone to the effects of IGF-I. These changes were associated with a concomitant increase in osteocalcin, taken as a reflection of bone formation. These results indicate that fluoride could potentiate the osteogenic effects of IGF-I on bone in adult ovariectomized rats.
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Affiliation(s)
- P Ammann
- WHO Collaborating Center for Osteoporosis and Bone Diseases, Department of Internal Medicine, University Hospital, Geneva, Switzerland
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24
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Caverzasio J, Palmer G, Suzuki A, Bonjour JP. Mechanism of the mitogenic effect of fluoride on osteoblast-like cells: evidences for a G protein-dependent tyrosine phosphorylation process. J Bone Miner Res 1997; 12:1975-83. [PMID: 9421230 DOI: 10.1359/jbmr.1997.12.12.1975] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Recent results indicate that a fluoroalumino complex (AlFx) is probably the molecule responsible for the mitogenic effect of fluoride in MC3T3-E1 osteoblast-like cells. Initial analysis suggested that a tyrosine phosphorylation (tyr phos) process similar to that induced by thrombin and activation of the p42 MAP kinase (ERK 2) mediate this cellular response. In the present study, the signaling mechanism activated by AlFx was further investigated. The results indicated that AlFx dose-dependently enhanced the tyr phos of the cell adhesion proteins FAK and paxillin, as well as of the adaptor molecules p46shc, p52shc, and p66shc and their association with GRB2. Pretreatment of MC3T3-E1 cells with cytochalasin D completely prevented FAK and paxillin tyr phos without any alteration in the tyr phos of Shc proteins and activation of ERK2 induced by AlFx. This observation suggests that in confluent MC3T3-E1 cells, there is no link between the activation of FAK induced by AlFx and the stimulation of ERK2. Pretreatment of the cells with pertussis toxin inhibited Shc phosphorylation, activation of ERK2, and markedly reduced cell replication induced by AlFx. This toxin also significantly reduced the stimulation of Pi transport activity induced by AlFx in these cells. Alteration in tyr phos induced by AlFx was not associated with any detectable inhibition of tyrosine phosphatase activity in MC3T3-E1 cell homogenates, suggesting that enhanced tyr phos induced by AlFx probably resulted from activation of a tyrosine kinase. In conclusion, the results of this study suggest that the mitogenic effect of fluoride in MC3T3-E1 osteoblast-like cells is mediated by the activation of a pertussis toxin-sensitive Gi/o protein and suggest an important role for these heterotrimeric G proteins in controlling the growth and differentiation of bone-forming cells.
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Affiliation(s)
- J Caverzasio
- Department of Medicine, University Hospital of Geneva, Switzerland
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25
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26
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Wu LW, Yoon HK, Baylink DJ, Graves LM, Lau KH. Fluoride at mitogenic doses induces a sustained activation of p44mapk, but not p42mapk, in human TE85 osteosarcoma cells. J Clin Endocrinol Metab 1997; 82:1126-35. [PMID: 9100584 DOI: 10.1210/jcem.82.4.3886] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Fluoride, at micromolar concentrations, stimulates bone cell proliferation in vitro. In this study, we sought to test whether fluoride at mitogenic doses increases the tyrosyl phosphorylation level and specific activity of a mitogen-activated protein kinase (MAPK) in human TE85 osteosarcoma cells. Analysis by immunoprecipitation with antiphosphotyrosine antibody followed by Western analysis using an anti-pan extracellular signal-regulated kinase antibody revealed that fluoride at the optimal mitogenic dose (i.e. 100 mumol/L) induced a time-dependent increase in the steady state tyrosyl phosphorylation level of p44mapk, but not p42mapk, with the maximal increase (4- to 13-fold) after 1-3 h fluoride treatment. The effect was sustained in that a 9-fold increase was seen after 12 h of the fluoride treatment. The sustained nature of the effect is consistent with an inhibition of dephosphorylation rather than a direct stimulation of phosphorylation. The fluoride effect on the tyrosyl phosphorylation level of p44mapk was dose dependent, with the optimal dose being 100 mumol/L fluoride. The mitogenic dose of fluoride also increased the specific activity and the in-gel kinase activity of p44mapk, but not that of p42mapk, in a time-dependent manner similar to the effect on the p44mapk tyrosyl phosphorylation level. Fluoride at the same micromolar doses did not increase cell proliferation, tyrosyl phosphorylation, or specific activity of any MAPK in human skin foreskin fibroblasts, which are fluoride-nonresponsive cells. Consistent with the interpretation that the effect of fluoride on the steady state tyrosyl phosphorylation level of p44mapk is a consequence of an inhibition of a phosphotyrosyl phosphatase (PTP), mitogenic doses of orthovanadate, a bone cell mitogen and a PTP inhibitor, also increased the steady state tyrosyl phosphorylation level of p44mapk, but not p42mapk, in a time-dependent sustained manner similar to that observed with fluoride. Together, these findings support the concept that inhibition of a PTP activity in bone cells could lead to an activation of MAPK activity.
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Affiliation(s)
- L W Wu
- Department of Medicine, Loma Linda University, California, USA
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27
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Imai T, Burgener D, Zhen X, Benjour JP, Caverzasio J. Aluminum potentiates P(i) transport stimulation induced by fluoride in osteoblast-like cells. THE AMERICAN JOURNAL OF PHYSIOLOGY 1996; 271:E694-701. [PMID: 8897857 DOI: 10.1152/ajpendo.1996.271.4.e694] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The effect of aluminum (AI) on inorganic phosphate (P(i)) transport stimulation induced by fluoride (F) was investigated in MC3T3-E1 osteoblast-like cells. Al potentiated the increase in P(i) transport activity induced by F in a dose- and time-dependent manner. Results obtained with deferoxamine mesylate, an Al chelator, suggest that a fluoroalumino complex is probably the active F molecule responsible for the change in P(i) transport observed in this study. The signaling pathway responsible for the stimulation of P(i) transport by F+Al likely involves a tyrosine phosphorylation process but neither a protein kinase C nor a mitogen-activated protein kinase pathway. As previously found in UMR-106 cells for F alone, F+Al potentiated the change in P(i) transport induced by fetal calf serum. A similar interaction was found between F+Al and thrombin acting through a G protein-coupled receptor. These observations are compatible with the hypothesis that F+Al could interact with G protein-coupled receptors associated with a signaling tyrosine phosphorylation process involved in the regulation of P(i), transport in osteoblast-like cells.
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Affiliation(s)
- T Imai
- Department of Medicine, University Hospital of Geneva, Switzerland
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28
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Caverzasio J, Imai T, Ammann P, Burgener D, Bonjour JP. Aluminum potentiates the effect of fluoride on tyrosine phosphorylation and osteoblast replication in vitro and bone mass in vivo. J Bone Miner Res 1996; 11:46-55. [PMID: 8770696 DOI: 10.1002/jbmr.5650110108] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Osteosclerosis in workers exposed to fluoride (F) and aluminum (Al) (industrial fluorosis) led to the use of F as a treatment to increase bone mass in osteoporosis patients. Because the influence of traces of Al on the effects of F on bone formation is heretofore unknown, we have investigated this issue both in vitro and in vivo. We have found that minute amounts of Al (< or = 10(-5) M) potentiate the effects of F in vitro such that osteoblast proliferation increased by 15 +/- 2.7% at 50 microM (p < 0.001) and by 117.6 +/- 5.1% at 750 microM (p < 0.001), concentrations of F with no mitogenic effect alone. F + Al time-dependently modulated a growth factor signaling pathway(s) associated with enhanced tyrosine phosphorylation (TyrP) of several proteins (p90 [2.9x], p77 [4.9x], p68 [9.6x], and mitogen activated protein kinases [3x]). TyrP was only slightly or not at all changed by F and Al alone, respectively. The effects of F + Al on TyrP and cell proliferation were markedly reduced by 100 microM tyrphostin-51, a tyrosine kinase inhibitor. Protein kinase A (PKA) and protein kinase C (PKC) pathways were not involved in this response. In vivo, F + Al administered for 8 months, at doses that had no effect when the minerals were administered individually, significantly enhanced proximal tibia bone mineral density (BMD) by 6.3 +/- 1% compared with initial values and by 2-fold compared with control ovariectomized rats (p < 0.0001). These effects are consistent with a crucial role of Al in osteosclerosis observed in industrial fluorosis. The results suggest that the combination of F + Al modulates a growth factor-dependent TyrP pathway enhancing mitogen-activated protein kinase and osteoblastic proliferation and bone mass.
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Affiliation(s)
- J Caverzasio
- Department of Medicine, University Hospital of Geneva, Switzerland
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