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Ferreira JRM, Greck AP. Adult mesenchymal stem cells and their possibilities for Dentistry: what to expect? Dental Press J Orthod 2020; 25:85-92. [PMID: 32844968 PMCID: PMC7437147 DOI: 10.1590/2177-6709.25.3.085-092.sar] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Accepted: 05/25/2020] [Indexed: 12/29/2022] Open
Abstract
INTRODUCTION Stem cells obtained from the pulp of human deciduous teeth are highly proliferative and plastic multipotent cells, which makes them a relevant model of stem cells, applied in several biomedical areas, with different purposes. OBJECTIVE Based on a brief review of the literature, the present work intends to present from conceptual aspects about stem cells, classifications, potential (in vitro and in vivo) applications in dental practice, cell culture, cryopreservation and its importance, ethical and regulatory aspects, as well as the role of the dental surgeon as the endorser responsible for the entire clinical stage that involves the process of collecting stem cells obtained from dental pulps for cryopreservation, with a view to using them under appropriate conditions, in accordance with scientifically proven and justified good laboratory and clinical practices.
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Stuepp RT, Barros Delben P, Modolo F, Trentin AG, Garcez RC, Biz MT. Human Dental Pulp Stem Cells in Rat Mandibular Bone Defects. Cells Tissues Organs 2019; 207:138-148. [PMID: 31734662 DOI: 10.1159/000502513] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Accepted: 08/06/2019] [Indexed: 11/19/2022] Open
Abstract
This study aimed to evaluate the use of human dental pulp stem cells (hDPSCs) in non-critical-sized mandibular bone defects in rats. hDPSCs from permanent teeth were isolated and engrafted in mandibular bone defects in rats for 7, 14, and 28 days; bone defects without cells formed the control group. Samples were evaluated by scanning electron microscopy (SEM), light microscopy (hematoxylin and eosin staining), and the regeneration area was measured by the Image J program. Before surgery procedures, the human dental pulp cells were characterized as dental pulp stem cells: fusiform morphology, plastic-adherent; expression of CD105, CD73, and CD90; lack of expression of CD45 and CD34, and differentiated into osteoblasts, adipocytes, and chondroblasts. The results indicated that within 7 days the control group presented a pronounced bone formation when compared with the treated group (p < 0.05). After 14 days, the treated group showed an increase in bone formation, but with no statistical difference among the groups (p > 0.05). In the final evaluated period there was no difference between the control group and the treated group (p > 0.05). There was a significant difference between 7 and 14 days (p < 0.05) and between 7 and 28 days (p < 0.05) in the treated group. In conclusion, there is no evidence that the use of hDPSCs in the conditions of this study could improve bone formation in non-critical-sized mandibular bone defects.
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Affiliation(s)
- Rubia Teodoro Stuepp
- Programa de Graduação em Odontologia, Universidade Federal de Santa Catarina, Florianópolis, Brazil
| | - Priscilla Barros Delben
- Programa de Pós-Graduação em Biologia Celular e do Desenvolvimento, Universidade Federal de Santa Catarina, Florianópolis, Brazil
| | - Filipe Modolo
- Departamento de Patologia, Universidade Federal de Santa Catarina, Florianópolis, Brazil
| | - Andrea Gonçalves Trentin
- Departamento de Biologia Celular, Embriologia e Genética, Universidade Federal de Santa Catarina, Florianópolis, Brazil
| | - Ricardo Castilho Garcez
- Departamento de Biologia Celular, Embriologia e Genética, Universidade Federal de Santa Catarina, Florianópolis, Brazil
| | - Michelle Tillmann Biz
- Departamento de Ciências Morfológicas, Universidade Federal de Santa Catarina, Florianópolis, Brazil,
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NURR1 Downregulation Favors Osteoblastic Differentiation of MSCs. Stem Cells Int 2017; 2017:7617048. [PMID: 28769982 PMCID: PMC5523352 DOI: 10.1155/2017/7617048] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2017] [Accepted: 06/12/2017] [Indexed: 02/06/2023] Open
Abstract
Mesenchymal stem cells (MSCs) have been identified in human dental tissues. Dental pulp stem cells (DPSCs) were classified within MSC family, are multipotent, can be isolated from adult teeth, and have been shown to differentiate, under particular conditions, into various cell types including osteoblasts. In this work, we investigated how the differentiation process of DPSCs toward osteoblasts is controlled. Recent literature data attributed to the nuclear receptor related 1 (NURR1), a still unclarified role in osteoblast differentiation, while NURR1 is primarily involved in dopaminergic neuron differentiation and activity. Thus, in order to verify if NURR1 had a role in DPSC osteoblastic differentiation, we silenced it during all the processes and compared the expression of the main osteoblastic markers with control cultures. Our results showed that the inhibition of NURR1 significantly increased the expression of osteoblast markers collagen I and alkaline phosphatase. Further, in long time cultures, the mineral matrix deposition was strongly enhanced in NURR1-silenced cultures. These results suggest that NURR1 plays a key role in switching DPSC differentiation toward osteoblasts rather than neuronal or even other cell lines. In conclusion, DPSCs represent a source of osteoblast-like cells and downregulation of NURR1 strongly prompted their differentiation toward the osteoblastogenesis process.
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Felice JI, Schurman L, McCarthy AD, Sedlinsky C, Aguirre JI, Cortizo AM. Effects of fructose-induced metabolic syndrome on rat skeletal cells and tissue, and their responses to metformin treatment. Diabetes Res Clin Pract 2017; 126:202-213. [PMID: 28259010 DOI: 10.1016/j.diabres.2017.02.011] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/30/2016] [Revised: 12/06/2016] [Accepted: 02/07/2017] [Indexed: 11/25/2022]
Abstract
AIMS Deleterious effects of metabolic syndrome (MS) on bone are still controversial. In this study we evaluated the effects of a fructose-induced MS, and/or an oral treatment with metformin on the osteogenic potential of bone marrow mesenchymal stromal cells (MSC), as well as on bone formation and architecture. METHODS 32 male 8week-old Wistar rats were assigned to four groups: control (C), control plus oral metformin (CM), rats receiving 10% fructose in drinking water (FRD), and FRD plus metformin (FRDM). Samples were collected to measure blood parameters, and to perform pQCT analysis and static and dynamic histomorphometry. MSC were isolated to determine their osteogenic potential. RESULTS Metformin improved blood parameters in FRDM rats. pQCT and static and dynamic histomorphometry showed no significant differences in trabecular and cortical bone parameters among groups. FRD reduced TRAP expression and osteocyte density in trabecular bone and metformin only normalized osteocyte density. FRD decreased the osteogenic potential of MSC and metformin administration could revert some of these parameters. CONCLUSIONS FRD-induced MS shows reduction in MSC osteogenic potential, in osteocyte density and in TRAP activity. Oral metformin treatment was able to prevent trabecular osteocyte loss and the reduction in extracellular mineralization induced by FRD-induced MS.
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Affiliation(s)
- Juan Ignacio Felice
- Laboratorio de Investigaciones en Osteopatías y Metabolismo Mineral (LIOMM), Facultad de Ciencias Exactas, Universidad Nacional de La Plata, Argentina
| | - León Schurman
- Laboratorio de Investigaciones en Osteopatías y Metabolismo Mineral (LIOMM), Facultad de Ciencias Exactas, Universidad Nacional de La Plata, Argentina
| | - Antonio Desmond McCarthy
- Laboratorio de Investigaciones en Osteopatías y Metabolismo Mineral (LIOMM), Facultad de Ciencias Exactas, Universidad Nacional de La Plata, Argentina
| | - Claudia Sedlinsky
- Laboratorio de Investigaciones en Osteopatías y Metabolismo Mineral (LIOMM), Facultad de Ciencias Exactas, Universidad Nacional de La Plata, Argentina
| | - José Ignacio Aguirre
- Department of Physiological Sciences, University of Florida, Gainesville, FL, USA
| | - Ana María Cortizo
- Laboratorio de Investigaciones en Osteopatías y Metabolismo Mineral (LIOMM), Facultad de Ciencias Exactas, Universidad Nacional de La Plata, Argentina.
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Tomazelli KB, Modolo F, Trentin AG, Garcez RC, Biz MT. Temporo-spatial analysis of Osterix, HNK1 and Sox10 during odontogenesis and maxillaries osteogenesis. Tissue Cell 2015; 47:465-70. [PMID: 26253417 DOI: 10.1016/j.tice.2015.07.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2015] [Revised: 07/21/2015] [Accepted: 07/24/2015] [Indexed: 01/09/2023]
Abstract
Cell differentiation is essential for maxillaries and tooth development. Facial mesenchymal tissue is formed by neural crest cells (NC). These cells are highly migratory, giving rise to various cell types, considered with a high level of plasticity, indicating that they contain progenitor cells with a great power of differentiation. In this study, it was analyzed the presence of NC cell progenitors and mesenchymal stem cells (MSC) during maxillaries osteogenesis and odontogenesis in rats. Histological slides were collected in two phases: embryonic age of 15 and 17 days; 2, 4 and 7 days after birth. Immunohistochemistry for MSC markers (Osterix) and NC cells (Sox10, HNK1) was performed. The results showed positive expression for Osterix and HNK1 in undifferentiated ectomesenchymal cells in early and late stages; Sox10 was present only in early stages in undifferentiated cells. All markers were present in differentiated cells. Although the experiments performed do not allow us to explain a possible role for Osx, HNK1 and Sox10 in both differentiated and undifferentiated cells during osteogenesis and odontogenesis, it had shown important results not yet described: the presence of HNK1 and Sox10 in osteoblasts and odontoblasts in late development stages and in the tooth germ epithelial cells and ameloblasts.
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Affiliation(s)
- Karin Berria Tomazelli
- Postgraduate Dentistry Program, Federal University of Santa Catarina, Florianópolis, SC, Brazil
| | - Filipe Modolo
- Pathology Department, Federal University of Santa Catarina, Florianopolis, SC, Brazil
| | - Andrea Gonçalves Trentin
- Cellular Biology, Embryology and Genetics Department, Federal University of Santa Catarina, Florianopolis, SC, Brazil
| | - Ricardo Castilho Garcez
- Cellular Biology, Embryology and Genetics Department, Federal University of Santa Catarina, Florianopolis, SC, Brazil
| | - Michelle Tillmann Biz
- Morphology Sciences Department, Federal University of Santa Catarina, Florianopolis, SC, Brazil.
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Nicotine stimulation increases proliferation and matrix metalloproteinases-2 and -28 expression in human dental pulp cells. Life Sci 2015; 135:49-54. [PMID: 26048072 DOI: 10.1016/j.lfs.2015.04.027] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Revised: 03/26/2015] [Accepted: 04/29/2015] [Indexed: 12/11/2022]
Abstract
AIMS Dental pulp is the specialized tissue responsible for maintaining tooth viability. When tooth mineralized matrix is damaged, pulp is exposed to a plethora of environmental stimuli. In particular, in smokers, pulp become exposed to very high concentrations of nicotine. The aim of this study was to investigate the effect of direct nicotine stimulation on human dental pulp cell proliferation. Moreover, as it is known that nicotine could upregulate the expression of matrix metalloproteinases (MMPs), enzymes involved in pulpal inflammation, the effects of nicotine stimulation on MMP-2 and MMP-28 gene expression have also been investigated. MAIN METHODS Human dental pulp cells were extracted from impacted third molars obtained from healthy patients undergoing routine orthodontic treatments. Such cells were treated with growing concentrations of nicotine in the presence or absence of a nicotine antagonist (hexamethonium chloride) or of a MEK signaling inhibitor (PD98059). Cell proliferation was evaluated by cell counting, while nicotine effects on MMP expression were evaluated by PCR. KEY FINDINGS The data obtained indicate that nicotine is able to increase human dental pulp cell proliferation by acting through nicotinic cholinergic receptors and downstream MAPK signaling pathway. Moreover, it is also able to increase both MMP-2 and MMP-28 gene expression. SIGNIFICANCE In summary these results highlight that direct exposure of human dental pulp cells to nicotine results in an inflammatory response, that could have a role in pulpal inflammation onset, a pathological condition that, when ignored, could eventually spread to the surrounding alveolar bone and progress to pulp necrosis.
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Felice JI, Gangoiti MV, Molinuevo MS, McCarthy AD, Cortizo AM. Effects of a metabolic syndrome induced by a fructose-rich diet on bone metabolism in rats. Metabolism 2014; 63:296-305. [PMID: 24355623 DOI: 10.1016/j.metabol.2013.11.002] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2013] [Revised: 10/22/2013] [Accepted: 11/03/2013] [Indexed: 11/28/2022]
Abstract
OBJECTIVE The aims of this study were: first, to evaluate the possible effects of a fructose rich diet (FRD)-induced metabolic syndrome (MS) on different aspects of long bone histomorphometry in young male rats; second, to investigate the effects of this diet on bone tissue regeneration; and third, to correlate these morphometric alterations with changes in the osteogenic/adipogenic potential and expression of specific transcription factors, of marrow stromal cells (MSC) isolated from rats with fructose-induced MS. MATERIALS/METHODS MS was induced in rats by treatment with a FRD for 28 days. Halfway through treatment, a parietal wound was made and bone healing was evaluated 14 days later. After treatments, histomorphometric analysis was performed in dissected femoral and parietal bones. MSC were isolated from the femora of control or fructose-treated rats and differentiated either to osteoblasts (evaluated by type 1 collagen, Alkaline phosphatase and extracellular nodule mineralization) or to adipocytes (evaluated by intracellular triglyceride accumulation). Expression of Runx2 and PPARγ was assessed by Western blot. RESULTS Fructose-induced MS induced deleterious effects on femoral metaphysis microarchitecture and impaired bone regeneration. Fructose treatment decreased the osteogenic potential of MSC and Runx2 expression. In addition, it increased the adipogenic commitment of MSC and PPARγ expression. CONCLUSIONS Fructose-induced MS is associated with deleterious effects on bone microarchitecture and with a decrease in bone repair. These alterations could be due to a deviation in the adipogenic/osteogenic commitment of MSC, probably by modulation of the Runx2/PPARγ ratio.
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Affiliation(s)
- Juan Ignacio Felice
- LIOMM (Laboratorio de Investigación en Osteopatías y Metabolismo Mineral), Department of Biological Sciences, School of Exact Sciences, National University of La Plata, La Plata, Argentina
| | - María Virginia Gangoiti
- LIOMM (Laboratorio de Investigación en Osteopatías y Metabolismo Mineral), Department of Biological Sciences, School of Exact Sciences, National University of La Plata, La Plata, Argentina
| | - María Silvina Molinuevo
- LIOMM (Laboratorio de Investigación en Osteopatías y Metabolismo Mineral), Department of Biological Sciences, School of Exact Sciences, National University of La Plata, La Plata, Argentina
| | - Antonio Desmond McCarthy
- LIOMM (Laboratorio de Investigación en Osteopatías y Metabolismo Mineral), Department of Biological Sciences, School of Exact Sciences, National University of La Plata, La Plata, Argentina
| | - Ana María Cortizo
- LIOMM (Laboratorio de Investigación en Osteopatías y Metabolismo Mineral), Department of Biological Sciences, School of Exact Sciences, National University of La Plata, La Plata, Argentina.
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Kim MJ, Lim HJ, Lee BG, Kim JH, Choi J, Kang HG. Establishment of Validation Methods to Test the Biocompatibility of Titanium Dioxide. B KOREAN CHEM SOC 2013. [DOI: 10.5012/bkcs.2013.34.6.1857] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Patil AS, Merchant Y, Nagarajan P. Tissue Engineering of Craniofacial Tissues – A Review. ACTA ACUST UNITED AC 2013. [DOI: 10.7243/2050-1218-2-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Sedlinsky C, Molinuevo MS, Cortizo AM, Tolosa MJ, Felice JI, Sbaraglini ML, Schurman L, McCarthy AD. Metformin prevents anti-osteogenic in vivo and ex vivo effects of rosiglitazone in rats. Eur J Pharmacol 2011; 668:477-85. [PMID: 21839072 DOI: 10.1016/j.ejphar.2011.07.033] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2010] [Revised: 06/30/2011] [Accepted: 07/24/2011] [Indexed: 02/08/2023]
Abstract
Long-term treatment with the insulin-sensitizer rosiglitazone reduces bone mass and increases fracture risk. We have recently shown that orally administered metformin stimulates bone reossification and increases the osteogenic potential of bone marrow progenitor cells (BMPC). In the present study we investigated the effect of a 2-week metformin and/or rosiglitazone treatment on bone repair, trabecular bone microarchitecture and BMPC osteogenic potential, in young male Sprague-Dawley rats. Compared to untreated controls, rosiglitazone monotherapy decreased bone regeneration, femoral metaphysis trabecular area, osteoblastic and osteocytic density, and TRAP activity associated with epiphyseal growth plates. It also decreased the ex vivo osteogenic commitment of BMPC, inducing an increase in PPARγ expression, and a decrease in Runx2/Cbfa1 expression, in AMP-kinase phosphorylation, and in osteoblastic differentiation and mineralization. After monotherapy with metformin, with the exception of PPARγ expression which was blunted, all of the above parameters were significantly increased (compared to untreated controls). Metformin/rosiglitazone co-treatment prevented all the in vivo and ex vivo anti-osteogenic effects of rosiglitazone monotherapy, with a reversion back to control levels of PPARγ, Runx2/Cbfa1 and AMP-kinase phosphorylation of BMPC. In vitro co-incubation of BMPC with metformin and compound C-an inhibitor of AMPK phosphorylation-abrogated the metformin-induced increase in type-1 collagen production, a marker of osteoblastic differentiation. In conclusion, in rodent models metformin not only induces direct osteogenic in vivo and ex vivo actions, but when it is administered orally in combination with rosiglitazone it can prevent several of the adverse effects that this thiazolidenedione shows on bone tissue.
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Affiliation(s)
- Claudia Sedlinsky
- GIOMM (Grupo de Investigación en Osteopatías y Metabolismo Mineral), Department of Biological Sciences, School of Exact Sciences, National University of La Plata, La Plata, Argentina
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Zeng J, Yang F, Zhang W, Gong Q, Du Y, Ling J. Association between dental pulp stones and calcifying nanoparticles. Int J Nanomedicine 2011; 6:109-18. [PMID: 21289988 PMCID: PMC3026576 DOI: 10.2147/ijn.s13267] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
The etiology of dental pulp stones, one type of extraskeletal calcification disease, remains elusive to date. Calcifying nanoparticles (CNPs), formerly referred to as nanobacteria, were reported to be one etiological factor in a number of extraskeletal calcification diseases. We hypothesized that CNPs are involved in the calcification of the dental pulp tissue, and therefore investigated the link between CNPs and dental pulp stones. Sixty-five freshly collected dental pulp stones, each from a different patient, were analyzed. Thirteen of the pulp stones were examined for the existence of CNPs in situ by immunohistochemical staining (IHS), indirect immunofluorescence staining (IIFS), and transmission electron microscope (TEM). The remaining 52 pulp stones were used for isolation and cultivation of CNPs; the cultured CNPs were identified and confirmed via their shape and growth characteristics. Among the dental pulp stones examined in situ, 84.6% of the tissue samples staines positive for CNPs antigen by IHS; the corresponding rate by IIFS was 92.3 %. In 88.2% of the cultured samples, CNPs were isolated and cultivated successfully. The CNPs were visible under TEM as 200–400 nm diameter spherical particles surrounded by a compact crust. CNPs could be detected and isolated from a high percentage of dental pulp stones, suggesting that CNPs might play an important role in the calcification of dental pulp.
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Affiliation(s)
- Jinfeng Zeng
- Department of Operative Dentistry and Endodontics, Guanghua School and Hospital of Stomatology and Institute of Stomatological Research, Sun Yat-sen University, Guangzhou, China
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Advanced and Prospective Technologies for Potential Use in Craniofacial Tissues Regeneration by Stem Cells and Growth Factors. J Craniofac Surg 2011; 22:342-8. [PMID: 21239932 DOI: 10.1097/scs.0b013e3181f7e185] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
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Ward BB, Brown SE, Krebsbach PH. Bioengineering strategies for regeneration of craniofacial bone: a review of emerging technologies. Oral Dis 2010; 16:709-16. [PMID: 20534013 DOI: 10.1111/j.1601-0825.2010.01682.x] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Although advances in surgical techniques and bone grafting have significantly improved the functional and cosmetic restoration of craniofacial structures lost because of trauma or disease, there are still significant limitations in our ability to regenerate these tissues. The regeneration of oral and craniofacial tissues presents a formidable challenge that requires synthesis of basic science, clinical science, and engineering technology. Tissue engineering is an interdisciplinary field of study that addresses this challenge by applying the principles of engineering to biology and medicine toward the development of biological substitutes that restore, maintain, and improve normal function. This review will explore the impact of biomaterials design, stem cell biology and gene therapy on craniofacial tissue engineering.
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Affiliation(s)
- B B Ward
- Department of Oral and Maxillofacial Surgery Biologic and Materials Sciences, School of Dentistry, University of Michigan Ann Arbor, MI, USA
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Effect of metformin on bone marrow progenitor cell differentiation: in vivo and in vitro studies. J Bone Miner Res 2010; 25:211-21. [PMID: 19594306 DOI: 10.1359/jbmr.090732] [Citation(s) in RCA: 149] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Diabetes mellitus is associated with bone loss. Patients with type 2 diabetes are frequently treated with oral antidiabetic drugs such as sulfonylureas, biguanides, and thiazolidinediones. Rosiglitazone treatment has been shown to increase adipogenesis in bone marrow and to induce bone loss. In this study we evaluated the effect of in vivo and in vitro treatment with metformin on bone marrow progenitor cells (BMPCs), as well as the involvement of AMPK pathway in its effects. The in vitro effect of coincubation with metformin and rosiglitazone on the adipogenic differentiation of BMPCs also was studied. In addition, we evaluated the effect of in vivo metformin treatment on bone regeneration in a model of parietal lesions in nondiabetic and streptozotocin-induced diabetic rats. We found that metformin administration both in vivo and in vitro caused an increase in alkaline phosphatase activity, type I collagen synthesis, osteocalcin expression, and extracellular calcium deposition of BMPCs. Moreover, metformin significantly activated AMPK in undifferentiated BMPCs. In vivo, metformin administration enhanced the expression of osteoblast-specific transcription factor Runx2/Cbfa1 and activation of AMPK in a time-dependent manner. Metformin treatment also stimulated bone lesion regeneration in control and diabetic rats. In vitro, metformin partially inhibited the adipogenic actions of rosiglitazone on BMPCs. In conclusion, our results indicate that metformin causes an osteogenic effect both in vivo and in vitro, possibly mediated by Runx2/Cbfa1 and AMPK activation, suggesting a possible action of metformin in a shift toward the osteoblastic differentiation of BMPCs.
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Abstract
Mesenchymal stem cells (MSCs) resident in bone marrow are one of the most studied and clinically important populations of adult stem cells. Cells with, similar properties to these MSCs have been described in several different tooth tissues and the potential ease with which these dental MSCs could be obtained from patients has prompted great interest in these cells as a source of MSCs for cell-based therapeutics. In this review we address the current state of knowledge regarding these cells, their properties, origins, locations, functions and potential uses in tooth tissue engineering and repair. We discuss some of the key controversies and outstanding issues, not least of which whether dental stem cells actually exist.
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Affiliation(s)
- Andrea Mantesso
- Guy's Hospital, Dental Institute, Kings College London, Department of Craniofacial Development, London SE1 9RT, UK
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16
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Kim NR, Lee DH, Ahn SJ, Lee IS, Yang HC. The differentiation-inducing effect of conditioned media obtained from dental pulp cells. ACTA ACUST UNITED AC 2009; 107:e54-9. [DOI: 10.1016/j.tripleo.2009.01.047] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2008] [Revised: 12/23/2008] [Accepted: 01/29/2009] [Indexed: 10/20/2022]
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17
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Miyazaki T, Miyauchi S, Tawada A, Anada T, Matsuzaka S, Suzuki O. Oversulfated chondroitin sulfate-E binds to BMP-4 and enhances osteoblast differentiation. J Cell Physiol 2008; 217:769-77. [DOI: 10.1002/jcp.21557] [Citation(s) in RCA: 98] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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18
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Abstract
Pulp stones are a frequent finding on bitewing and periapical radiographs but receive relatively little attention in textbooks. A review of the literature was therefore performed, initially using the PubMed database and beginning the search with 'pulp calcifications' and 'pulp stones'. Each term provided more than 400 references, many of which related to pulp calcification in general rather than pulp stones, and focussed largely on the problems these changes presented to clinicians. A manual search using references from this source was carried out. Contemporary textbooks in endodontology were also consulted, and an historic perspective gained from a number of older books and references. The factors involved in the development of the pulp stones are largely unknown. Further research may determine the reasons for their formation, but with current endodontic instruments and techniques this is unlikely to alter their relevance to clinicians.
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Affiliation(s)
- R Goga
- Private Endodontic Practice, Johnsonville, Wellington, New Zealand
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Mao JJ, Giannobile WV, Helms JA, Hollister SJ, Krebsbach PH, Longaker MT, Shi S. Craniofacial tissue engineering by stem cells. J Dent Res 2007; 85:966-79. [PMID: 17062735 PMCID: PMC2571078 DOI: 10.1177/154405910608501101] [Citation(s) in RCA: 236] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Craniofacial tissue engineering promises the regeneration or de novo formation of dental, oral, and craniofacial structures lost to congenital anomalies, trauma, and diseases. Virtually all craniofacial structures are derivatives of mesenchymal cells. Mesenchymal stem cells are the offspring of mesenchymal cells following asymmetrical division, and reside in various craniofacial structures in the adult. Cells with characteristics of adult stem cells have been isolated from the dental pulp, the deciduous tooth, and the periodontium. Several craniofacial structures--such as the mandibular condyle, calvarial bone, cranial suture, and subcutaneous adipose tissue--have been engineered from mesenchymal stem cells, growth factor, and/or gene therapy approaches. As a departure from the reliance of current clinical practice on durable materials such as amalgam, composites, and metallic alloys, biological therapies utilize mesenchymal stem cells, delivered or internally recruited, to generate craniofacial structures in temporary scaffolding biomaterials. Craniofacial tissue engineering is likely to be realized in the foreseeable future, and represents an opportunity that dentistry cannot afford to miss.
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Affiliation(s)
- J J Mao
- Columbia University College of Dental Medicine and Biomedical Engineering, 630 W. 168 St.--PH7 CDM, New York, NY 10032, USA.
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Ueno A, Yamashita K, Miyoshi K, Horiguchi T, Ruspita I, Abe K, Noma T. Soluble matrix from osteoblastic cells induces mineralization by dental pulp cells. THE JOURNAL OF MEDICAL INVESTIGATION 2006; 53:297-302. [PMID: 16953068 DOI: 10.2152/jmi.53.297] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Dental pulp cells have a capacity to differentiate into mineralization-inducing cells. To clarify the molecular mechanism, we established an in vitro mineralization-inducing system by rat clonal dental pulp cell line, RPC-C2A, and tried to purify a mineralization-inducing factor in conditioned medium (CM) from pre-osteoblastic MC3T3-E1 cells. The active factor was impermeable to an ultrafiltration membrane, and sedimented by ultracentrifugation. The sedimented factor was found as a needle-like structure about 1.3 microm in average length as observed by transmission electron microscopy. The factor contained type I collagen, suggesting not a matrix vesicle, but a soluble matrix. The mineralization-inducing activity was also detected in CM from primary culture of rat calvaria (RC) cells. These results suggested that the soluble matrices from osteoblastic cells serve, at least in part, as differentiation-inducing agents.
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Affiliation(s)
- Akemichi Ueno
- Department of Molecular Biology, The University of Tokushima Graduate School
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Ueno A, Miwa Y, Miyoshi K, Horiguchi T, Inoue H, Ruspita I, Abe K, Yamashita K, Hayashi E, Noma T. Constitutive expression of thrombospondin 1 in MC3T3-E1 osteoblastic cells inhibits mineralization. J Cell Physiol 2006; 209:322-32. [PMID: 16883596 DOI: 10.1002/jcp.20735] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Thrombospondin 1 (TSP1) is a multifunctional extracellular glycoprotein present mainly in the fetal and adult skeleton. Although an inhibitory effect of TSP1 against pathological mineralization in cultured vascular pericytes has been shown, its involvement in physiological mineralization by osteoblasts is still unknown. To determine the role of TSP1 in biomineralization, mouse osteoblastic MC3T3-E1 cells were cultured in the presence of antisense phosphorothioate oligodeoxynucleotides complementary to the TSP1 sequence. The 18- and 24-mer antisense oligonucleotides caused concentration-dependent increases in the number of mineralized nodules, acid-soluble calcium deposition in the cell/matrix layer, and alkaline phosphatase activity within 9 days, without affecting cell proliferation. The corresponding sense or scrambled oligonucleotides did not affect these parameters. In the antisense oligonucleotide-treated MC3T3-E1 cells, thickened extracellular matrix, well-developed cell processes, increased intracellular organelles, and collagen fibril bundles were observed. On the other hand, the addition of TSP1 to the culture decreased the production of a mineralized matrix by MC3T3-E1 cells. Furthermore, MC3T3-E1 clones overexpressing mouse TSP1 were established and assayed for TSP1 protein and their capacity to mineralize. TSP1 dose-dependently inhibited mineralization by these cells both in vitro and in vivo. These results indicate that TSP1 functions as an inhibitory regulator of bone mineralization and matrix production by osteoblasts to sustain bone homeostasis.
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Affiliation(s)
- Akemichi Ueno
- Department of Molecular Biology, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima, Japan
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Cortizo AM, Sedlinsky C, McCarthy AD, Blanco A, Schurman L. Osteogenic actions of the anti-diabetic drug metformin on osteoblasts in culture. Eur J Pharmacol 2006; 536:38-46. [PMID: 16564524 DOI: 10.1016/j.ejphar.2006.02.030] [Citation(s) in RCA: 170] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2005] [Revised: 02/10/2006] [Accepted: 02/17/2006] [Indexed: 12/22/2022]
Abstract
An association has been previously established between uncompensated diabetes mellitus and the loss of bone mineral density and/or quality. In this study, we evaluated the effects of metformin on the growth and differentiation of osteoblasts in culture. Treatment of two osteoblast-like cells (UMR106 and MC3T3E1) with metformin (25-500 microM) for 24 h led to a dose-dependent increase of cell proliferation. Metformin also promoted osteoblastic differentiation: it increased type-I collagen production in both cell lines and stimulated alkaline phosphatase activity in MC3T3E1 osteoblasts. In addition, metformin markedly increased the formation of nodules of mineralization in 3-week MC3T3E1 cultures. Metformin induced activation and redistribution of phosphorylated extracellular signal-regulated kinase (P-ERK) in a transient manner, and dose-dependently stimulated the expression of endothelial and inducible nitric oxide synthases (e/iNOS). These results show for the first time a direct osteogenic effect of metformin on osteoblasts in culture, which could be mediated by activation/redistribution of ERK-1/2 and induction of e/iNOS.
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Affiliation(s)
- Ana M Cortizo
- Cátedra de Bioquímica Patológica, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 1900 La Plata, and Centro de Endocrinología y Metabolismo, Hospital Francés, Buenos Aires, Argentina.
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Cortizo AM, Molinuevo MS, Barrio DA, Bruzzone L. Osteogenic activity of vanadyl(IV)–ascorbate complex: Evaluation of its mechanism of action. Int J Biochem Cell Biol 2006; 38:1171-80. [PMID: 16455285 DOI: 10.1016/j.biocel.2005.12.007] [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] [Received: 06/24/2005] [Revised: 11/16/2005] [Accepted: 12/11/2005] [Indexed: 11/18/2022]
Abstract
We have previously shown that different vanadium(IV) complexes regulate osteoblastic growth. Since vanadium compounds are accumulated in vivo in bone, they may affect bone turnover. The development of vanadium complexes with different ligands could be an alternative strategy of use in skeletal tissue engineering. In this study, we have investigated the osteogenic properties of a vanadyl(IV)-ascorbate (VOAsc) complex, as well as its possible mechanisms of action, on two osteoblastic cell lines in culture. VOAsc (2.5-25 microM) significantly stimulated osteoblastic proliferation (113-125% basal, p<0.01) in UMR106 cells, but not in the MC3T3E1 cell line. VOAsc (5-100 micrioM) dose-dependently stimulated type-I collagen production (107-156% basal) in osteoblasts. After 3 weeks of culture, 5-25 microM VOAsc increased the formation of nodules of mineralization in MC3T3E1 cells (7.7-20-fold control, p<0.001). VOAsc (50-100 microM) significantly stimulated apoptosis in both cell lines (170-230% basal, p<0.02-0.002), but did not affect reactive oxygen species production. The complex inhibited alkaline and neutral phosphatases from osteoblastic extracts with semi-maximal effect at 10 microM doses. VOAsc induced the activation and redistribution of P-ERK in a time- and dose-dependent manner. Inhibitors of the mitogen activated protein kinases (MAPK) pathway (PD98059 and UO126) partially blocked the VOAsc-enhanced osteoblastic proliferation and collagen production. In addition, wortmanin, a PI-3-K inhibitor and type-L channel blocker nifedipine also partially abrogated these effects of VOAsc on osteoblasts. Our in vitro results suggest that this vanadyl(IV)-ascorbate complex could be a useful pharmacological tool for bone tissue regeneration.
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Affiliation(s)
- Ana M Cortizo
- Cátedra de Bioquímica Patológica, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 y 115, 1900 La Plata, Argentina.
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Liu H, Li W, Shi S, Habelitz S, Gao C, Denbesten P. MEPE is downregulated as dental pulp stem cells differentiate. Arch Oral Biol 2005; 50:923-8. [PMID: 16183369 DOI: 10.1016/j.archoralbio.2005.03.003] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2004] [Accepted: 03/01/2005] [Indexed: 01/09/2023]
Abstract
UNLABELLED Previous studies on dental pulp cell culture have described heterogenous mixtures of cells that differentiate into odontoblasts and form mineralized dentin. OBJECTIVE The aim of this study was to characterize the matrix extracellular phosphoglycoprotein (MEPE) expression by dental pulp stem cells (DPSC), related to cell differentiation. DESIGN DPSC differentiation to form mineralized nodules was characterized by Alizarin red staining and micro-Raman spectroscopy. Osteogenesis SuperArray analysis was used to broadly screen for osteogenesis-related genes altered by DPSC differentiation. Relative levels of expression of MEPE and DSP were determined by semiquantitative RT-PCR and Western blot. RESULTS Mineral analysis showed that as DPSC differentiated, they formed a carbonated hydroxyapatite mineral. Differentiation was initially marked by upregulation by Runx2, TGFbeta-related genes, EGFR and genes involved in collagen metabolism. ALP activity first increased, as DPSCs reached confluence but later decreased when cells further differentiated three weeks after confluence. MEPE was the only marker that was downregulated as DPSCs differentiated. CONCLUSION DPSC differentiation can be characterized by downregulation of MEPE as other markers of DPSC differentiation, such as DSP, are upregulated. Expression of MEPE related to DSP and can be used to monitor DPSC as they are used for studies of odontoblast differentiation, tissue engineering or vital pulp therapy. The downregulation of MEPE as DPSC differentiate, suggests that MEPE is an inhibitor of mineralization.
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Affiliation(s)
- He Liu
- University of California, San Francisco, Growth and Development, 521 Parnassus Avenue, Rm C734, Box 0640, San Francisco, CA 94143-0640, USA
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Shi S, Bartold PM, Miura M, Seo BM, Robey PG, Gronthos S. The efficacy of mesenchymal stem cells to regenerate and repair dental structures. Orthod Craniofac Res 2005; 8:191-9. [PMID: 16022721 DOI: 10.1111/j.1601-6343.2005.00331.x] [Citation(s) in RCA: 323] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
OBJECTIVES Identification, characterization, and potential application of mesenchymal stem cells (MSC) derived from human dental tissues. METHODS Dental pulp and periodontal ligament were obtained from normal human impacted third molars. The tissues were digested in collagenase/dispase to generate single cell suspensions. Cells were cultured in alpha-MEM supplemented with 20% fetal bovine serum, 2 mM l-glutamine, 100 microM l-ascorbate-2-phosphate. Magnetic and fluorescence activated cell sorting were employed to characterize the phenotype of freshly isolated and ex vivo expanded cell populations. The developmental potential of cultured cells was assessed following co-transplantation with hydroxyapetite/tricalcium phosphate (HA/TCP) particles into immunocompromised mice for 8 weeks. RESULTS MSC were identified in adult human dental pulp (dental pulp stem cells, DPSC), human primary teeth (stem cells from human exfoliated deciduous teeth, SHED), and periodontal ligament (periodontal ligament stem cells, PDLSC) by their capacity to generate clongenic cell clusters in culture. Ex vivo expanded DPSC, SHED, and PDLSC populations expressed a heterogeneous assortment of makers associated with MSC, dentin, bone, smooth muscle, neural tissue, and endothelium. PDLSC were also found to express the tendon specific marker, Scleraxis. Xenogeneic transplants containing HA/TCP with either DPSC or SHED generated donor-derived dentin-pulp-like tissues with distinct odontoblast layers lining the mineralized dentin-matrix. In parallel studies, PDLSC generated cementum-like structures associated with PDL-like connective tissue when transplanted with HA/TCP into immunocompromised mice. CONCLUSION Collectively, these data revealed the presence of distinct MSC populations associated with dental structures with the potential of stem cells to regenerate living human dental tissues in vivo.
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Affiliation(s)
- S Shi
- Craniofacial and Skeletal Diseases Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, MD, USA
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Goldberg M, Smith AJ, Nagai N. Cells and Extracellular Matrices of Dentin and Pulp: A Biological Basis for Repair and Tissue Engineering. J HARD TISSUE BIOL 2004. [DOI: 10.2485/jhtb.13.55] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Goldberg M, Smith AJ. CELLS AND EXTRACELLULAR MATRICES OF DENTIN AND PULP: A BIOLOGICAL BASIS FOR REPAIR AND TISSUE ENGINEERING. ACTA ACUST UNITED AC 2004; 15:13-27. [PMID: 14761897 DOI: 10.1177/154411130401500103] [Citation(s) in RCA: 352] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Odontoblasts produce most of the extracellular matrix (ECM) components found in dentin and implicated in dentin mineralization. Major differences in the pulp ECM explain why pulp is normally a non-mineralized tissue. In vitro or in vivo, some dentin ECM molecules act as crystal nucleators and contribute to crystal growth, whereas others are mineralization inhibitors. After treatment of caries lesions of moderate progression, odontoblasts and cells from the sub-odontoblastic Höhl's layer are implicated in the formation of reactionary dentin. Healing of deeper lesions in contact with the pulp results in the formation of reparative dentin by pulp cells. The response to direct pulp-capping with materials such as calcium hydroxide is the formation of a dentinal bridge, resulting from the recruitment and proliferation of undifferentiated cells, which may be either stem cells or dedifferentiated and transdifferentiated mature cells. Once differentiated, the cells synthesize a matrix that undergoes mineralization. Animal models have been used to test the capacity of potentially bioactive molecules to promote pulp repair following their implantation into the pulp. ECM molecules induce either the formation of dentinal bridges or large areas of mineralization in the coronal pulp. They may also stimulate the total closure of the pulp in the root canal. In conclusion, some molecules found in dentin extracellular matrix may have potential in dental therapy as bioactive agents for pulp repair or tissue engineering.
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Affiliation(s)
- Michel Goldberg
- Faculté de Chirurgie Dentaire, Université Paris V-René Descartes, Groupe Matrices Extracellulaires et biominéralisations (EA 2496), 1, rue Maurice Arnoux, 92120 Montrouge, France
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Abstract
Mesenchymal stem cell populations have previously been identified in adult bone marrow and dental pulp that are capable of regenerating the bone marrow and dental pulp microenvironments, respectively. Here we show that these stem cell populations reside in the microvasculature of their tissue of origin. Human bone marrow stromal stem cells (BMSSCs) and dental pulp stem cells (DPSCs) were isolated by immunoselection using the antibody, STRO-1, which recognizes an antigen on perivascular cells in bone marrow and dental pulp tissue. Freshly isolated STRO-1 positive BMSSCs and DPSCs were tested for expression of vascular antigens known to be expressed by endothelial cells (von Willebrand factor, CD146), smooth muscle cells, and pericytes (alpha-smooth muscle actin, CD146), and a pericyte-associated antigen (3G5), by immunohistochemistry, fluorescence-activated cell sorting (FACS), and/or immunomagnetic bead selection. Both BMSSCs and DPSCs lacked expression of von Willebrand factor but were found to be positive for alpha-smooth muscle actin and CD146. Furthermore, the majority of DPSCs expressed the pericyte marker, 3G5, while only a minor population of BMSSCs were found to be positive for 3G5. The finding that BMSSCs and DPSCs both display phenotypes consistent with different perivascular cell populations, regardless of their diverse ontogeny and developmental potentials, may have further implications in understanding the factors that regulate the formation of mineralized matrices and other associated connective tissues.
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Affiliation(s)
- Songtao Shi
- Craniofacial and Skeletal Diseases Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, Maryland, USA
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Lundquist P, Ritchie HH, Moore K, Lundgren T, Linde A. Phosphate and calcium uptake by rat odontoblast-like MRPC-1 cells concomitant with mineralization. J Bone Miner Res 2002; 17:1801-13. [PMID: 12369784 DOI: 10.1359/jbmr.2002.17.10.1801] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
It has been suggested that odontoblasts are instrumental in translocating Ca2+ and inorganic phosphate (Pi) ions during the mineralization of dentin. The aim of this study was to characterize cellular Pi and Ca2+ uptake in the novel rat odontoblast-like cell line mineralizing rat pulpal cell line (MRPC) 1 during mineralization to see if changes in the ion transport activity would occur as the cultures develop and begin forming a mineralized matrix. MRPC-1 cells were cultured in chemically defined medium containing ascorbate and Pi, and cultures were specifically analyzed for cellular P, and Ca2+ uptake activities and expression of type II high-capacity Na+-Pi cotransporters. The odontoblast-like phenotype of the cell line was ascertained by monitoring the expression of collagen type I and dentin phosphopoprotein (DPP). Mineralized nodule formation started at day 9 after confluency and then rapidly increased. Ca2+ uptake by the cells showed a maximum during the end of the proliferative phase (days 5-7). Pi uptake declined to a basal level during proliferation and then was up-regulated simultaneously with the onset of mineralization to a level fourfold of the basal uptake, suggesting an initiating and regulatory role for cellular Pi uptake in mineral formation. This up-regulation coincided with a conspicuously increased glycosylation of NaPi-2a, indicating an activation of this Na+-Pi cotransporter. The study showed that MRPC-1 cells express an odontoblast-like phenotype already at the onset of culture, but that to mineralize the collagenous extracellular matrix (ECM) that formed, a further differentiation involving their ion transporters is necessary.
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Affiliation(s)
- P Lundquist
- Department of Oral Biochemistry, Faculty of Odontology, Göteborg University, Sweden
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