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Phang V, Malhotra R, Chen NN, Min KS, Yu VSH, Rosa V, Dubey N. Specimen Shape and Elution Time Affect the Mineralization and Differentiation Potential of Dental Pulp Stem Cells to Biodentine. J Funct Biomater 2023; 15:1. [PMID: 38276474 PMCID: PMC10816296 DOI: 10.3390/jfb15010001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Revised: 12/11/2023] [Accepted: 12/14/2023] [Indexed: 01/27/2024] Open
Abstract
The liquid extract method is commonly used to evaluate the cytotoxicity and bioactivity of materials. Although ISO has recommended guidelines for test methods, variations in elution period, and shape of samples can influence the biological outcomes. The aim of this study was to investigate the influence of material form and elution period of Biodentine on dental pulp stem cells (DPSCs)' proliferation and mineralization. Biodentine (0.2 g) discs or powder were immersed in culture media (10 mL) for 1, 3 or 7 days (D1, D3 and D7). The eluents were filtered and used to treat DPSC. The calcium release profile and pH were determined. Cell proliferation was evaluated by MTS for 3 days, and mineralization and differentiation were assessed by alizarin red S staining (Ca2+/ng of DNA) and qRT-PCR (MEPE, DSPP, DMP-1, RUNX2, COL-I and OCN) for 14 days. Statistical analysis was performed with a one or two-way ANOVA and post hoc Tukey's test (pH, calcium release and proliferation) or Mann-Whitney test (α = 0.05). pH and calcium ion release of powdered eluents were significantly higher than disc eluents. Powdered eluent promoted extensive cell death, while the disc form was cytocompatible. All disc eluents significantly increased the gene expression and mineralization after 14 days compared to the untreated control. D7 induced less mineralization and differentiation compared to D1 and D3. Thus, the materials' form and elution time are critical aspects to be considered when evaluating the bioactivity of materials, since this binomial can affect positively and negatively the biological outcomes.
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Affiliation(s)
- Valene Phang
- Faculty of Dentistry, National University of Singapore, Singapore 119085, Singapore; (V.P.); (R.M.); (V.S.H.Y.)
- National Dental Centre Singapore, 5 Second Hospital Ave., Singapore 168938, Singapore;
| | - Ritika Malhotra
- Faculty of Dentistry, National University of Singapore, Singapore 119085, Singapore; (V.P.); (R.M.); (V.S.H.Y.)
| | - Nah Nah Chen
- National Dental Centre Singapore, 5 Second Hospital Ave., Singapore 168938, Singapore;
| | - Kyung-San Min
- Department of Conservative Dentistry, School of Dentistry, Jeonbuk National University, Jeonju 54896, Republic of Korea;
| | - Victoria Soo Hoon Yu
- Faculty of Dentistry, National University of Singapore, Singapore 119085, Singapore; (V.P.); (R.M.); (V.S.H.Y.)
| | - Vinicius Rosa
- Faculty of Dentistry, National University of Singapore, Singapore 119085, Singapore; (V.P.); (R.M.); (V.S.H.Y.)
| | - Nileshkumar Dubey
- Faculty of Dentistry, National University of Singapore, Singapore 119085, Singapore; (V.P.); (R.M.); (V.S.H.Y.)
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Morita T, Matsumoto S, Baba O. Expression of secretory calcium-binding phosphoprotein (scpp) genes in medaka during the formation and replacement of pharyngeal teeth. BMC Oral Health 2023; 23:744. [PMID: 37821862 PMCID: PMC10568847 DOI: 10.1186/s12903-023-03498-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Accepted: 10/06/2023] [Indexed: 10/13/2023] Open
Abstract
BACKGROUND Analyses of tooth families and tooth-forming units in medaka with regard to tooth replacement cycles and the localization of odontogenic stem cell niches in the pharyngeal dentition clearly indicate that continuous tooth replacement is maintained. The secretory calcium-binding phosphoprotein (scpp) gene cluster is involved in the formation of mineralized tissues, such as dental and bone tissues, and the genes encoding multiple SCPPs are conserved in fish, amphibians, reptiles, and mammals. In the present study, we examined the expression patterns of several scpp genes in the pharyngeal teeth of medaka to elucidate their roles during tooth formation and replacement. METHODS Himedaka (Japanese medaka, Oryzias latipes) of both sexes (body length: 28 to 33 mm) were used in this study. Real-time quantitative reverse transcription-polymerase chain reaction (PCR) (qPCR) data were evaluated using one-way analysis of variance for multi-group comparisons, and the significance of differences was determined by Tukey's comparison test. The expression of scpp genes was examined using in situ hybridization (ISH) with a digoxigenin-labeled, single-stranded antisense probe. RESULTS qPCR results showed that several scpp genes were strongly expressed in pharyngeal tissues. ISH analysis revealed specific expression of scpp1, scpp5, and sparc in tooth germ, and scpp5 was continually expressed in the odontoblasts of teeth attached to pedicles, but not in the osteoblasts of pedicles. In addition, many scpp genes were expressed in inner dental epithelium (ide), but not in odontoblasts, and scpp2 consistently showed epithelial-specific expression in the functional teeth. Taken together, these data indicate that specific expression of scpp2 and scpp5 may play a critical role in pharyngeal tooth formation in medaka. CONCLUSION We characterized changes in the expression patterns of scpp genes in medaka during the formation and replacement of pharyngeal teeth.
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Affiliation(s)
- Tsuyoshi Morita
- Department of Oral and Maxillofacial Anatomy, Institute of Biomedical Sciences, Tokushima University Graduate School, 3-18-15, Kuramoto-cho, Tokushima-shi, Tokushima, 770-8504, Japan.
| | - Shin Matsumoto
- Oral Surgery Department, St. Luke's International Hospital, 9-1, Akashi-cho, Chuo-ku, Tokyo, 104-8560, Japan
| | - Otto Baba
- Department of Oral and Maxillofacial Anatomy, Institute of Biomedical Sciences, Tokushima University Graduate School, 3-18-15, Kuramoto-cho, Tokushima-shi, Tokushima, 770-8504, Japan
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Ouchi T, Nakagawa T. Cellular Signaling for Dental Physiological Functions. Biomolecules 2023; 13:1177. [PMID: 37627242 PMCID: PMC10452277 DOI: 10.3390/biom13081177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Accepted: 07/27/2023] [Indexed: 08/27/2023] Open
Abstract
Teeth are unique and multifaceted tissues that are necessary for routine functions, such as crushing food and constructing articulated sounds, as well as for esthetic symbols [...].
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Affiliation(s)
- Takehito Ouchi
- Department of Physiology, Tokyo Dental College, Tokyo 101-0061, Japan
- Department of Dentistry and Oral Surgery, Keio University School of Medicine, Tokyo 160-8582, Japan
| | - Taneaki Nakagawa
- Department of Dentistry and Oral Surgery, Keio University School of Medicine, Tokyo 160-8582, Japan
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Kim JS, Lee BN, Chang HS, Hwang IN, Oh WM, Hwang YC. Effects of CTHRC1 on odontogenic differentiation and angiogenesis in human dental pulp stem cells. Restor Dent Endod 2023; 48:e18. [PMID: 37284346 PMCID: PMC10240092 DOI: 10.5395/rde.2023.48.e18] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Revised: 02/08/2023] [Accepted: 02/08/2023] [Indexed: 06/08/2023] Open
Abstract
Objectives This study aimed to determine whether collagen triple helix repeat containing-1 (CTHRC1), which is involved in vascular remodeling and bone formation, can stimulate odontogenic differentiation and angiogenesis when administered to human dental pulp stem cells (hDPSCs). Materials and Methods The viability of hDPSCs upon exposure to CTHRC1 was assessed with the WST-1 assay. CTHRC1 doses of 5, 10, and 20 µg/mL were administered to hDPSCs. Reverse-transcription polymerase reaction was used to detect dentin sialophosphoprotein, dentin matrix protein 1, vascular endothelial growth factor, and fibroblast growth factor 2. The formation of mineralization nodules was evaluated using Alizarin red. A scratch wound assay was conducted to evaluate the effect of CTHRC1 on cell migration. Data were analyzed using 1-way analysis of variance followed by the Tukey post hoc test. The threshold for statistical significance was set at p < 0.05. Results CTHRC1 doses of 5, 10, and 20 µg/mL had no significant effect on the viability of hDPSCs. Mineralized nodules were formed and odontogenic markers were upregulated, indicating that CTHRC1 promoted odontogenic differentiation. Scratch wound assays demonstrated that CTHRC1 significantly enhanced the migration of hDPSCs. Conclusions CTHRC1 promoted odontogenic differentiation and mineralization in hDPSCs.
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Affiliation(s)
- Jong-soon Kim
- Department of Conservative Dentistry, School of Dentistry, Chonnam National University, Gwangju, Korea
| | - Bin-Na Lee
- Department of Conservative Dentistry, School of Dentistry, Chonnam National University, Gwangju, Korea
| | - Hoon-Sang Chang
- Department of Conservative Dentistry, School of Dentistry, Chonnam National University, Gwangju, Korea
| | - In-Nam Hwang
- Department of Conservative Dentistry, School of Dentistry, Chonnam National University, Gwangju, Korea
| | - Won-Mann Oh
- Department of Conservative Dentistry, School of Dentistry, Chonnam National University, Gwangju, Korea
| | - Yun-Chan Hwang
- Department of Conservative Dentistry, School of Dentistry, Chonnam National University, Gwangju, Korea
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Nijakowski K, Ortarzewska M, Jankowski J, Lehmann A, Surdacka A. The Role of Cellular Metabolism in Maintaining the Function of the Dentine-Pulp Complex: A Narrative Review. Metabolites 2023; 13:metabo13040520. [PMID: 37110177 PMCID: PMC10143950 DOI: 10.3390/metabo13040520] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Revised: 04/04/2023] [Accepted: 04/04/2023] [Indexed: 04/29/2023] Open
Abstract
The cellular metabolic processes ensure the physiological integrity of the dentine-pulp complex. Odontoblasts and odontoblast-like cells are responsible for the defence mechanisms in the form of tertiary dentine formation. In turn, the main defence reaction of the pulp is the development of inflammation, during which the metabolic and signalling pathways of the cells are significantly altered. The selected dental procedures, such as orthodontic treatment, resin infiltration, resin restorations or dental bleaching, can impact the cellular metabolism in the dental pulp. Among systemic metabolic diseases, diabetes mellitus causes the most consequences for the cellular metabolism of the dentine-pulp complex. Similarly, ageing processes present a proven effect on the metabolic functioning of the odontoblasts and the pulp cells. In the literature, several potential metabolic mediators demonstrating anti-inflammatory properties on inflamed dental pulp are mentioned. Moreover, the pulp stem cells exhibit the regenerative potential essential for maintaining the function of the dentine-pulp complex.
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Affiliation(s)
- Kacper Nijakowski
- Department of Conservative Dentistry and Endodontics, Poznan University of Medical Sciences, 60-812 Poznan, Poland
| | - Martyna Ortarzewska
- Department of Conservative Dentistry and Endodontics, Poznan University of Medical Sciences, 60-812 Poznan, Poland
| | - Jakub Jankowski
- Student's Scientific Group in the Department of Conservative Dentistry and Endodontics, Poznan University of Medical Sciences, 60-812 Poznan, Poland
| | - Anna Lehmann
- Department of Conservative Dentistry and Endodontics, Poznan University of Medical Sciences, 60-812 Poznan, Poland
| | - Anna Surdacka
- Department of Conservative Dentistry and Endodontics, Poznan University of Medical Sciences, 60-812 Poznan, Poland
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Tian C, Chai J, Liu W, Zhang X, Li Y, Zuo H, Yuan G, Zhang H, Liu H, Chen Z. Role of the Demethylase AlkB Homolog H5 in the Promotion of Dentinogenesis. Front Physiol 2022; 13:923185. [PMID: 35784864 PMCID: PMC9240783 DOI: 10.3389/fphys.2022.923185] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Accepted: 05/23/2022] [Indexed: 11/25/2022] Open
Abstract
Dentinogenesis is a key process in tooth formation and is regulated by a series of pre- and post-transcriptional regulations. N6-methyl-adenosine (m6A), which is the most prevalent internal chemical modification that can be removed by the RNA demethylase AlkB homolog H5 (ALKBH5), has recently been reported to be involved in several biological processes. However, the exact function of ALKBH5-mediated m6A modification in tooth development remains unclear. Here, we showed that Alkbh5 was expressed in pre-odontoblasts, polarizing odontoblasts, and secretory odontoblasts. Alkbh5 overexpression in the mouse dental papilla cell line mDPC6T promoted odontoblastic differentiation. Conditional knockout of Alkbh5 in Dmp1-expressing odontoblasts led to a decrease in number of odontoblasts and increased pre-dentin formation. Mechanistically, RNA sequencing and m6A sequencing of Alkbh5-overexpressing mDPC6T cells revealed that Alkbh5 promoted odontoblast differentiation by prolonging the half-life of Runx2 transcripts in an m6A-dependent manner and by activating the phosphatidylinositol 3-kinase/protein kinase B pathway. Notably, the loss of Alkbh5 expression in odontoblasts impaired tertiary dentin formation in vivo. These results suggested that the RNA demethylase ALKBH5 plays a role in dentinogenesis.
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Affiliation(s)
- Cheng Tian
- The State Key Laboratory Breeding Base of Basic Sciences of Stomatology, Key Laboratory of Oral Biomedicine, Ministry of Education (Hubei-MOST KLOS & KLOBM), School and Hospital of Stomatology, Wuhan University, Wuhan, China
| | - Jihua Chai
- The State Key Laboratory Breeding Base of Basic Sciences of Stomatology, Key Laboratory of Oral Biomedicine, Ministry of Education (Hubei-MOST KLOS & KLOBM), School and Hospital of Stomatology, Wuhan University, Wuhan, China
| | - Weidong Liu
- The State Key Laboratory Breeding Base of Basic Sciences of Stomatology, Key Laboratory of Oral Biomedicine, Ministry of Education (Hubei-MOST KLOS & KLOBM), School and Hospital of Stomatology, Wuhan University, Wuhan, China
| | - Xinye Zhang
- The State Key Laboratory Breeding Base of Basic Sciences of Stomatology, Key Laboratory of Oral Biomedicine, Ministry of Education (Hubei-MOST KLOS & KLOBM), School and Hospital of Stomatology, Wuhan University, Wuhan, China
| | - Yashu Li
- Frontier Science Center for Immunology and Metabolism, Medical Research Institute, School of Medicine, Wuhan University, Wuhan, China
| | - Huanyan Zuo
- The State Key Laboratory Breeding Base of Basic Sciences of Stomatology, Key Laboratory of Oral Biomedicine, Ministry of Education (Hubei-MOST KLOS & KLOBM), School and Hospital of Stomatology, Wuhan University, Wuhan, China
| | - Guohua Yuan
- The State Key Laboratory Breeding Base of Basic Sciences of Stomatology, Key Laboratory of Oral Biomedicine, Ministry of Education (Hubei-MOST KLOS & KLOBM), School and Hospital of Stomatology, Wuhan University, Wuhan, China
| | - Haojian Zhang
- The State Key Laboratory Breeding Base of Basic Sciences of Stomatology, Key Laboratory of Oral Biomedicine, Ministry of Education (Hubei-MOST KLOS & KLOBM), School and Hospital of Stomatology, Wuhan University, Wuhan, China
- Frontier Science Center for Immunology and Metabolism, Medical Research Institute, School of Medicine, Wuhan University, Wuhan, China
| | - Huan Liu
- The State Key Laboratory Breeding Base of Basic Sciences of Stomatology, Key Laboratory of Oral Biomedicine, Ministry of Education (Hubei-MOST KLOS & KLOBM), School and Hospital of Stomatology, Wuhan University, Wuhan, China
- Department of Periodontology, School and Hospital of Stomatology, Wuhan University, Wuhan, China
- *Correspondence: Huan Liu, ; Zhi Chen,
| | - Zhi Chen
- The State Key Laboratory Breeding Base of Basic Sciences of Stomatology, Key Laboratory of Oral Biomedicine, Ministry of Education (Hubei-MOST KLOS & KLOBM), School and Hospital of Stomatology, Wuhan University, Wuhan, China
- Department of Cariology and Endodontics, School and Hospital of Stomatology, Wuhan University, Wuhan, China
- *Correspondence: Huan Liu, ; Zhi Chen,
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Zhang Q, Huang Z, Zuo H, Lin Y, Xiao Y, Yan Y, Cui Y, Lin C, Pei F, Chen Z, Liu H. Chromatin Accessibility Predetermines Odontoblast Terminal Differentiation. Front Cell Dev Biol 2021; 9:769193. [PMID: 34901015 PMCID: PMC8655119 DOI: 10.3389/fcell.2021.769193] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Accepted: 10/29/2021] [Indexed: 12/03/2022] Open
Abstract
Embryonic development and stem cell differentiation are orchestrated by changes in sequential binding of regulatory transcriptional factors to their motifs. These processes are invariably accompanied by the alternations in chromatin accessibility, conformation, and histone modification. Odontoblast lineage originates from cranial neural crest cells and is crucial in dentinogenesis. Our previous work revealed several transcription factors (TFs) that promote odontoblast differentiation. However, it remains elusive as to whether chromatin accessibility affects odontoblast terminal differentiation. Herein, integration of single-cell RNA-seq and bulk RNA-seq revealed that in vitro odontoblast differentiation using dental papilla cells at E18.5 was comparable to the crown odontoblast differentiation trajectory of OC (osteocalcin)-positive odontogenic lineage. Before in vitro odontoblast differentiation, ATAC-seq and H3K27Ac CUT and Tag experiments demonstrated high accessibility of chromatin regions adjacent to genes associated with odontogenic potential. However, following odontoblastic induction, regions near mineralization-related genes became accessible. Integration of RNA-seq and ATAC-seq results further revealed that the expression levels of these genes were correlated with the accessibility of nearby chromatin. Time-course ATAC-seq experiments further demonstrated that odontoblast terminal differentiation was correlated with the occupation of the basic region/leucine zipper motif (bZIP) TF family, whereby we validated the positive role of ATF5 in vitro. Collectively, this study reports a global mapping of open chromatin regulatory elements during dentinogenesis and illustrates how these regions are regulated via dynamic binding of different TF families, resulting in odontoblast terminal differentiation. The findings also shed light on understanding the genetic regulation of dentin regeneration using dental mesenchymal stem cells.
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Affiliation(s)
- Qian Zhang
- The State Key Laboratory Breeding Base of Basic Science of Stomatology and Key Laboratory for Oral Biomedicine of Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan, China
| | - Zhen Huang
- Fujian Key Laboratory of Developmental and Neuro Biology, College of Life Science, Fujian Normal University, Fuzhou, China
| | - Huanyan Zuo
- The State Key Laboratory Breeding Base of Basic Science of Stomatology and Key Laboratory for Oral Biomedicine of Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan, China
| | - Yuxiu Lin
- The State Key Laboratory Breeding Base of Basic Science of Stomatology and Key Laboratory for Oral Biomedicine of Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan, China
| | - Yao Xiao
- The State Key Laboratory Breeding Base of Basic Science of Stomatology and Key Laboratory for Oral Biomedicine of Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan, China
| | - Yanan Yan
- Fujian Key Laboratory of Developmental and Neuro Biology, College of Life Science, Fujian Normal University, Fuzhou, China
| | - Yu Cui
- The State Key Laboratory Breeding Base of Basic Science of Stomatology and Key Laboratory for Oral Biomedicine of Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan, China
| | - Chujiao Lin
- Division of Rheumatology, Department of Medicine, University of Massachusetts Medical School, Worcester, MA, United States
| | - Fei Pei
- The State Key Laboratory Breeding Base of Basic Science of Stomatology and Key Laboratory for Oral Biomedicine of Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan, China
| | - Zhi Chen
- The State Key Laboratory Breeding Base of Basic Science of Stomatology and Key Laboratory for Oral Biomedicine of Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan, China
| | - Huan Liu
- The State Key Laboratory Breeding Base of Basic Science of Stomatology and Key Laboratory for Oral Biomedicine of Ministry of Education, School and Hospital of Stomatology, Wuhan University, Wuhan, China.,Department of Periodontology, School of Stomatology, Wuhan University, Wuhan, China
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Chitosan-Based Accelerated Portland Cement Promotes Dentinogenic/Osteogenic Differentiation and Mineralization Activity of SHED. Polymers (Basel) 2021; 13:polym13193358. [PMID: 34641172 PMCID: PMC8512062 DOI: 10.3390/polym13193358] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Revised: 09/05/2021] [Accepted: 09/25/2021] [Indexed: 01/26/2023] Open
Abstract
Calcium silicate-based cements (CSCs) are widely used in various endodontic treatments to promote wound healing and hard tissue formation. Chitosan-based accelerated Portland cement (APC-CT) is a promising and affordable material for endodontic use. This study investigated the effect of APC-CT on apoptosis, cell attachment, dentinogenic/osteogenic differentiation and mineralization activity of stem cells from human exfoliated deciduous teeth (SHED). APC-CT was prepared with various concentrations of chitosan (CT) solution (0%, 0.625%, 1.25% and 2.5% (w/v)). Cell attachment was determined by direct contact analysis using field emission scanning electron microscopy (FESEM); while the material extracts were used for the analyses of apoptosis by flow cytometry, dentinogenic/osteogenic marker expression by real-time PCR and mineralization activity by Alizarin Red and Von Kossa staining. The cells effectively attached to the surfaces of APC and APC-CT, acquiring flattened elongated and rounded-shape morphology. Treatment of SHED with APC and APC-CT extracts showed no apoptotic effect. APC-CT induced upregulation of DSPP, MEPE, DMP-1, OPN, OCN, OPG and RANKL expression levels in SHED after 14 days, whereas RUNX2, ALP and COL1A1 expression levels were downregulated. Mineralization assays showed a progressive increase in the formation of calcium deposits in cells with material containing higher CT concentration and with incubation time. In conclusion, APC-CT is nontoxic and promotes dentinogenic/osteogenic differentiation and mineralization activity of SHED, indicating its regenerative potential as a promising substitute for the commercially available CSCs to induce dentin/bone regeneration.
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Liu K, Yu S, Ye L, Gao B. The Regenerative Potential of bFGF in Dental Pulp Repair and Regeneration. Front Pharmacol 2021; 12:680209. [PMID: 34354584 PMCID: PMC8329335 DOI: 10.3389/fphar.2021.680209] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2021] [Accepted: 06/22/2021] [Indexed: 02/05/2023] Open
Abstract
Regenerative endodontic therapy intends to induce the host’s natural wound-healing process, which can restore the vitality, immunity, and sensitivity of the inflammatory or necrotic pulp tissue destroyed by infection or trauma. Myriads of growth factors are critical in the processes of pulp repair and regeneration. Among the key regulatory factors are the fibroblast growth factors, which have turned out to be the master regulators of both organogenesis and tissue homeostasis. Fibroblast growth factors, a family composed of 22 polypeptides, have been used in tissue repair and regeneration settings, in conditions as diverse as burns, ulcers, bone-related diseases, and spinal cord injuries. Meanwhile, in dentistry, the basic fibroblast growth factor is the most frequently investigated. Thereby, the aim of this review is 2-fold: 1) foremost, to explore the underlying mechanisms of the bFGF in dental pulp repair and regeneration and 2) in addition, to shed light on the potential therapeutic strategies of the bFGF in dental pulp–related clinical applications.
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Affiliation(s)
- Keyue Liu
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Sijing Yu
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Ling Ye
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Bo Gao
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
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Isono K, Takahashi E, Miyoshi I, Tsuneto M, Hikosaka-Kuniishi M, Yamane T, Yamazaki H. Simultaneous Fluorescent Identification of Odontoblasts and Ameloblasts. J Dent Res 2020; 100:532-541. [PMID: 33289448 DOI: 10.1177/0022034520974576] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The tooth is mainly composed of dentin and enamel. Identification of dentin-producing odontoblasts and enamel-producing ameloblasts using reporter techniques is useful to study tooth development and regeneration with tissue engineering. Ameloblasts express Amelogenin, Ameloblastin, Enamelin, and Amelotin, whereas odontoblasts express Dentin sialophosphoprotein (Dspp) and Dentin matrix protein1 (Dmp1). Although there are several transgenic lines using promoter elements or bacterial artificial chromosomes (BACs) to label odontoblasts and ameloblasts, there is a possibility that the expression patterns vary from the endogenous genes. Here, we established 2 lines of mice where tdTomato was knocked into the second exon of X-chromosomal Amelogenin (Amelx), and green fluorescent protein (GFP) was knocked into the second exon of Dspp. tdTomato and GFP were highly expressed on secretory ameloblasts and secretory and fully differentiated odontoblasts, respectively. In addition, DSPP and AMELX were not produced in the dentin matrix and enamel matrix of DsppGFP/GFP and AmelxtdTomato male mice (as representative of AmelxtdTomato/Y hemizygous male mice), respectively. Moreover, micro-computed tomography analysis of AmelxtdTomato male mice revealed a notable reduction in enamel volume but increased dentin mineral density. DsppGFP/GFP mice had reduced dentin mineral density. To identify odontoblasts and ameloblasts from developing tooth, we examined the expression of mesenchymal cell surface molecules CD90, CD166 and epithelial cell surface molecules CD49f, Epcam1 with fluorescence on odontoblasts and ameloblasts in these mice. We found that GFP+ odontoblasts and tdTomato+ ameloblasts in tooth germ from 0.5-d-old DsppGFP/+ mice and AmelxtdTomato male mice were enriched in CD45-/Ter119-/Epcam1-/CD90+/Integrin α4+cell fractions and CD45-/Ter119-/Epcam1+/CD49f+/CD147+ cell fractions, respectively. By using antibodies against mesenchymal and epithelial cell surface molecules and fluorescence, we can easily distinguish odontoblasts from ameloblasts and isolate each cell for further studies. These mice would serve as useful models for tooth development and regeneration as well as provide concurrent observation for the differentiation processes of odontoblasts and ameloblasts in vivo and in vitro.
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Affiliation(s)
- K Isono
- Department of Stem Cells and Developmental Biology, Division of Fundamental Medicine, Mie University Graduate School of Medicine, Tsu, Mie, Japan
| | - E Takahashi
- Support Unit for Animal Resources Development, Research Resources Division, RIKEN Center for Brain Science, Wako-shi, Saitama, Japan
| | - I Miyoshi
- Department of Laboratory Animal Medicine, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
| | - M Tsuneto
- Division of Regenerative Medicine and Therapeutics, Department of Genetic Medicine and Regenerative Therapeutics, Tottori University Graduate School of Medical Science, Yonago, Tottori, Japan
| | - M Hikosaka-Kuniishi
- Department of Stem Cells and Developmental Biology, Division of Fundamental Medicine, Mie University Graduate School of Medicine, Tsu, Mie, Japan
| | - T Yamane
- Department of Stem Cells and Developmental Biology, Division of Fundamental Medicine, Mie University Graduate School of Medicine, Tsu, Mie, Japan
| | - H Yamazaki
- Department of Stem Cells and Developmental Biology, Division of Fundamental Medicine, Mie University Graduate School of Medicine, Tsu, Mie, Japan
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Son JW, Choi SH, Jang JH, Koh JT, Oh WM, Hwang YC, Lee BN. Irisin promotes odontogenic differentiation and angiogenic potential in human dental pulp cells. Int Endod J 2020; 54:399-412. [PMID: 33089893 DOI: 10.1111/iej.13435] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Revised: 10/19/2020] [Accepted: 10/19/2020] [Indexed: 12/31/2022]
Abstract
AIM To determine whether irisin, a newly discovered myokine that links exercise-induced and metabolic homeostasis, is able to promote odontogenic differentiation and angiogenesis in human dental pulp cells (HDPCs). METHODOLOGY Cell viability in the presence of irisin was measured. Real-time PCR and Western blot analysis were performed to evaluate the expression levels of irisin, odontogenic and angiogenic markers. The involvement of mitogen-activated protein kinase (MAPK) and the protein kinase B (Akt) signalling pathway was evaluated by Western blot. To evaluate mineralization nodule formation, alkaline phosphatase (ALP) staining and alizarin red S staining were performed. Scratch wound assays were performed to evaluate the effects of irisin on cell migration. The data were analysed using one-way analysis of variance (anova) followed by Tukey post hoc test and Student's t-test. Statistical significance was considered at P < 0.05. RESULTS Irisin significantly promoted odontogenic differentiation as evidenced by formation of mineralized nodules, induction of ALP activity and upregulation of odontogenic and angiogenic markers (P < 0.05). Scratch wound assays revealed that irisin significantly increased migration of HDPCs (P < 0.05). Phosphorylation of both MAPK and Akt was increased by irisin. MAPK and Akt inhibitors inhibited mineralization, cell migration and the increased expression of odontogenic and angiogenic markers. CONCLUSIONS Irisin promoted odontogenic differentiation and mineralization and has the potential for angiogenesis through activation of the MAPK and Akt signalling pathways in HDPCs.
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Affiliation(s)
- J W Son
- Department of Conservative Dentistry, School of Dentistry, Dental Science Research Institute, Chonnam National University, Gwangju, Korea
| | - S H Choi
- Department of Conservative Dentistry, School of Dentistry, Dental Science Research Institute, Chonnam National University, Gwangju, Korea
| | - J H Jang
- Department of Conservative Dentistry, School of Dentistry, Kyung Hee University, Seoul, Korea
| | - J T Koh
- Department of Pharmacology and Dental Therapeutics, Hard-tissue Biointerface Research Center, School of Dentistry, Dental Science Research Institute, Chonnam National University, Gwangju, Korea
| | - W M Oh
- Department of Conservative Dentistry, School of Dentistry, Dental Science Research Institute, Chonnam National University, Gwangju, Korea
| | - Y C Hwang
- Department of Conservative Dentistry, School of Dentistry, Dental Science Research Institute, Chonnam National University, Gwangju, Korea
| | - B N Lee
- Department of Conservative Dentistry, School of Dentistry, Dental Science Research Institute, Chonnam National University, Gwangju, Korea
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Krivanek J, Soldatov RA, Kastriti ME, Chontorotzea T, Herdina AN, Petersen J, Szarowska B, Landova M, Matejova VK, Holla LI, Kuchler U, Zdrilic IV, Vijaykumar A, Balic A, Marangoni P, Klein OD, Neves VCM, Yianni V, Sharpe PT, Harkany T, Metscher BD, Bajénoff M, Mina M, Fried K, Kharchenko PV, Adameyko I. Dental cell type atlas reveals stem and differentiated cell types in mouse and human teeth. Nat Commun 2020; 11:4816. [PMID: 32968047 PMCID: PMC7511944 DOI: 10.1038/s41467-020-18512-7] [Citation(s) in RCA: 122] [Impact Index Per Article: 30.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2020] [Accepted: 08/24/2020] [Indexed: 01/09/2023] Open
Abstract
Understanding cell types and mechanisms of dental growth is essential for reconstruction and engineering of teeth. Therefore, we investigated cellular composition of growing and non-growing mouse and human teeth. As a result, we report an unappreciated cellular complexity of the continuously-growing mouse incisor, which suggests a coherent model of cell dynamics enabling unarrested growth. This model relies on spatially-restricted stem, progenitor and differentiated populations in the epithelial and mesenchymal compartments underlying the coordinated expansion of two major branches of pulpal cells and diverse epithelial subtypes. Further comparisons of human and mouse teeth yield both parallelisms and differences in tissue heterogeneity and highlight the specifics behind growing and non-growing modes. Despite being similar at a coarse level, mouse and human teeth reveal molecular differences and species-specific cell subtypes suggesting possible evolutionary divergence. Overall, here we provide an atlas of human and mouse teeth with a focus on growth and differentiation.
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Affiliation(s)
- Jan Krivanek
- Department of Molecular Neuroscience, Center for Brain Research, Medical University of Vienna, Vienna, Austria
- Department of Histology and Embryology, Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - Ruslan A Soldatov
- Department of Biomedical Informatics, Harvard Medical School, Boston, MA, USA
| | - Maria Eleni Kastriti
- Department of Molecular Neuroscience, Center for Brain Research, Medical University of Vienna, Vienna, Austria
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Tatiana Chontorotzea
- Department of Molecular Neuroscience, Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Anna Nele Herdina
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Julian Petersen
- Department of Molecular Neuroscience, Center for Brain Research, Medical University of Vienna, Vienna, Austria
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
| | - Bara Szarowska
- Department of Molecular Neuroscience, Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Marie Landova
- Institute of Animal Physiology and Genetics, CAS, Brno, Czech Republic
| | - Veronika Kovar Matejova
- Clinic of Stomatology, Institution Shared with St. Anne's Faculty Hospital, Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - Lydie Izakovicova Holla
- Clinic of Stomatology, Institution Shared with St. Anne's Faculty Hospital, Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - Ulrike Kuchler
- Department of Oral Biology, Medical University of Vienna, Vienna, Austria
- Department of Oral Surgery, Medical University of Vienna, Vienna, Austria
| | - Ivana Vidovic Zdrilic
- Department of Craniofacial Sciences, School of Dental Medicine, University of Connecticut Health Center, Farmington, CT, USA
| | - Anushree Vijaykumar
- Department of Craniofacial Sciences, School of Dental Medicine, University of Connecticut Health Center, Farmington, CT, USA
| | - Anamaria Balic
- Research Program in Developmental Biology, Institute of Biotechnology, University of Helsinki, Helsinki, Finland
| | - Pauline Marangoni
- Program in Craniofacial Biology and Department of Orofacial Sciences, University of California, San Francisco, CA, USA
| | - Ophir D Klein
- Program in Craniofacial Biology and Department of Orofacial Sciences, University of California, San Francisco, CA, USA
- Department of Pediatrics and Institute for Human Genetics, University of California, San Francisco, CA, USA
| | - Vitor C M Neves
- Centre for Craniofacial and Regenerative Biology, Faculty of Dentistry, Oral & Craniofacial Sciences. King's College London, London, UK
| | - Val Yianni
- Centre for Craniofacial and Regenerative Biology, Faculty of Dentistry, Oral & Craniofacial Sciences. King's College London, London, UK
| | - Paul T Sharpe
- Centre for Craniofacial and Regenerative Biology, Faculty of Dentistry, Oral & Craniofacial Sciences. King's College London, London, UK
| | - Tibor Harkany
- Department of Molecular Neuroscience, Center for Brain Research, Medical University of Vienna, Vienna, Austria
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Brian D Metscher
- Department of Evolutionary Biology, University of Vienna, Vienna, Austria
| | - Marc Bajénoff
- Centre d'Immunologie de Marseille-Luminy, Aix Marseille Université, INSERM, CNRS UMR, Marseille, France
| | - Mina Mina
- Department of Craniofacial Sciences, School of Dental Medicine, University of Connecticut Health Center, Farmington, CT, USA
| | - Kaj Fried
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Peter V Kharchenko
- Department of Biomedical Informatics, Harvard Medical School, Boston, MA, USA.
| | - Igor Adameyko
- Department of Molecular Neuroscience, Center for Brain Research, Medical University of Vienna, Vienna, Austria.
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden.
- Department of Neuroimmunology, Center for Brain Research, Medical University of Vienna, Vienna, Austria.
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Vijaykumar A, Dyrkacz P, Vidovic-Zdrilic I, Maye P, Mina M. Expression of BSP-GFPtpz Transgene during Osteogenesis and Reparative Dentinogenesis. J Dent Res 2020; 99:89-97. [PMID: 31682548 PMCID: PMC6927219 DOI: 10.1177/0022034519885089] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Bone sialoprotein (BSP) is a member of the SIBLING family with essential roles in skeletogenesis. In the developing teeth, although the expression and function of BSP in the formation of acellular cementum and periodontal attachment are well documented, there are uncertainties regarding the expression and function of BSP by odontoblasts and dentin. Reporter mice are valuable animal models for biological research, providing a gene expression readout that can contribute to cellular characterization within the context of a developmental process. In the present study, we examined the expression of a BSP-GFPtpz reporter mouse line during odontoblast differentiation, reparative dentinogenesis, and bone. In the developing teeth, BSP-GFPtpz was expressed at high levels in cementoblasts but not in odontoblasts or dentin. In bones, the transgene was highly expressed in osteoblasts at an early stage of differentiation. Interestingly, despite its lack of expression in odontoblasts and dental pulp during tooth development, the BSP-GFPtpz transgene was detected during in vitro mineralization of primary pulp cultures and during reparative dentinogenesis following pulp exposures. Importantly, under these experimental contexts, the expression of BSP-GFPtpz was still exclusive to DSPP-Cerulean, an odontoblast-specific reporter gene. This suggests that the combinatorial use of BSP-GFPtpz and DSPP-Cerulean can be a valuable experimental tool to distinguish osteogenic from dentinogenic cells, thereby providing an avenue to investigate mechanisms that distinctly regulate the lineage progression of progenitors into odontoblasts versus osteoblasts.
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Affiliation(s)
- A. Vijaykumar
- Department of Craniofacial Sciences, School of Dental Medicine, University of Connecticut, Farmington, CT, USA
| | - P. Dyrkacz
- Department of Craniofacial Sciences, School of Dental Medicine, University of Connecticut, Farmington, CT, USA
| | - I. Vidovic-Zdrilic
- Department of Craniofacial Sciences, School of Dental Medicine, University of Connecticut, Farmington, CT, USA
| | - P. Maye
- Department of Reconstructive Sciences, School of Dental Medicine, University of Connecticut, Farmington, CT, USA
| | - M. Mina
- Department of Craniofacial Sciences, School of Dental Medicine, University of Connecticut, Farmington, CT, USA
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Rajan S, Ljunggren A, Manton DJ, Björkner AE, McCullough M. Post-mitotic odontoblasts in health, disease, and regeneration. Arch Oral Biol 2019; 109:104591. [PMID: 31710968 DOI: 10.1016/j.archoralbio.2019.104591] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Revised: 10/09/2019] [Accepted: 10/20/2019] [Indexed: 12/25/2022]
Abstract
OBJECTIVE Description of the odontoblast lifecycle, an overview of the known complex molecular interactions that occur when the health of the dental pulp is challenged and the current and future management strategies on vital and non-vital teeth. METHODS A literature search of the electronic databases included MEDLINE (1966-April 2019), CINAHL (1982-April 2019), EMBASE and EMBASE Classic (1947-April 2019), and hand searches of references retrieved were undertaken using the following MESH terms 'odontoblast*', 'inflammation', 'dental pulp*', 'wound healing' and 'regenerative medicine'. RESULTS Odontoblasts have a sensory and mechano-transduction role so as to detect external stimuli that challenge the dental pulp. On detection, odontoblasts stimulate the innate immunity by activating defence mechanisms key in the healing and repair mechanisms of the tooth. A better understanding of the role of odontoblasts within the dental pulp complex will allow an opportunity for biological management to remove the cause of the insult to the dental pulp, modulate the inflammatory process, and promote the healing and repair capabilities of the tooth. Current strategies include use of conventional dental pulp medicaments while newer methods include bioactive molecules, epigenetic modifications and tissue engineering. CONCLUSION Regenerative medicine methods are in their infancy and experimental stages at best. This review highlights the future direction of dental caries management and consequently research.
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Affiliation(s)
- S Rajan
- The University of Melbourne, Australia.
| | | | - D J Manton
- The University of Melbourne, Australia; Centrum voor Tandheelkunde en Mondzorgkunde, UMCG, University of Groningen, the Netherlands
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15
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Vijaykumar A, Ghassem-Zadeh S, Vidovic-Zdrilic I, Komitas K, Adameyko I, Krivanek J, Fu Y, Maye P, Mina M. Generation and characterization of DSPP-Cerulean/DMP1-Cherry reporter mice. Genesis 2019; 57:e23324. [PMID: 31271259 PMCID: PMC6939995 DOI: 10.1002/dvg.23324] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Revised: 06/13/2019] [Accepted: 06/14/2019] [Indexed: 12/24/2022]
Abstract
To gain a better understanding of the progression of progenitor cells in the odontoblast lineage, we have examined and characterized the expression of a series of GFP reporters during odontoblast differentiation. However, previously reported GFP reporters (pOBCol2.3-GFP, pOBCol3.6-GFP, and DMP1-GFP), similar to the endogenous proteins, are also expressed by bone-forming cells, which made it difficult to delineate the two cell types in various in vivo and in vitro studies. To overcome these difficulties we generated DSPP-Cerulean/DMP1-Cherry transgenic mice using a bacterial recombination strategy with the mouse BAC clone RP24-258g7. We have analyzed the temporal and spatial expression of both transgenes in tooth and bone in vivo and in vitro. This transgenic animal enabled us to visualize the interactions between odontoblasts and surrounding tissues including dental pulp, ameloblasts and cementoblasts. Our studies showed that DMP1-Cherry, similar to Dmp1, was expressed in functional and fully differentiated odontoblasts as well as osteoblasts, osteocytes and cementoblasts. Expression of DSPP-Cerulean transgene was limited to functional and fully differentiated odontoblasts and correlated with the expression of Dspp. This transgenic animal can help in the identification and isolation of odontoblasts at later stages of differentiation and help in better understanding of developmental disorders in dentin and odontoblasts.
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Affiliation(s)
- Anushree Vijaykumar
- Department of Craniofacial Sciences School of Dental Medicine, University of Connecticut, Farmington, Connecticut
| | - Sean Ghassem-Zadeh
- Department of Craniofacial Sciences School of Dental Medicine, University of Connecticut, Farmington, Connecticut
| | - Ivana Vidovic-Zdrilic
- Department of Craniofacial Sciences School of Dental Medicine, University of Connecticut, Farmington, Connecticut
| | - Karren Komitas
- Department of Craniofacial Sciences School of Dental Medicine, University of Connecticut, Farmington, Connecticut
| | - Igor Adameyko
- Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden
- Center for Brain Research, Medical University of Vienna, Vienna, Austria
| | - Jan Krivanek
- Center for Brain Research, Medical University of Vienna, Vienna, Austria
- Department of Histology and Embryology, Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - Yu Fu
- Department of Reconstructive Sciences, School of Dental Medicine, University of Connecticut, Farmington, Connecticut
| | - Peter Maye
- Department of Reconstructive Sciences, School of Dental Medicine, University of Connecticut, Farmington, Connecticut
| | - Mina Mina
- Department of Craniofacial Sciences School of Dental Medicine, University of Connecticut, Farmington, Connecticut
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16
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Qin W, Gao X, Ma T, Weir MD, Zou J, Song B, Lin Z, Schneider A, Xu HHK. Metformin Enhances the Differentiation of Dental Pulp Cells into Odontoblasts by Activating AMPK Signaling. J Endod 2018; 44:576-584. [PMID: 29306537 DOI: 10.1016/j.joen.2017.11.017] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Revised: 09/29/2017] [Accepted: 11/20/2017] [Indexed: 12/22/2022]
Abstract
INTRODUCTION Metformin is a first-line drug for treating type 2 diabetes that regulates the differentiation of mesenchymal stem cells. Its effects on human dental pulp cells (DPCs) remain unknown. This study aimed to investigate the effects of metformin on the proliferation and differentiation of DPCs. METHODS A live/dead viability assay kit was used to examine the effects of metformin on the cell viability of DPCs. Cell proliferation was analyzed using a cell counting kit (CCK-8; Dojindo, Tokyo, Japan). Levels of phosphorylated and unphosphorylated adenosine 5'-monophosphate-activated protein kinase (AMPK) were quantified by Western blot analysis in response to metformin and the AMPK signaling inhibitor Compound C (EMD Chemicals, San Diego, CA). The effects of Compound C on the metformin-induced odontoblast differentiation of DPCs were determined by alkaline phosphatase activity assay and von Kossa staining, and the expression of odontoblastic markers was evaluated by reverse-transcription polymerase chain reaction analysis. RESULTS DPCs exhibited mesenchymal stem cell characteristics using flow cytometry. Different doses of metformin were shown to be cytocompatible with DPCs, yielding >90% cell viability. None of the concentrations of metformin up to 50 μmol/L affected cell proliferation. The Western blot assay showed that DPCs express functional organic cation transporter 1, a transmembrane protein that mediates the intracellular uptake of metformin. Metformin significantly activated the AMPK pathway in a dose-dependent manner. In addition, it stimulated alkaline phosphatase activity; enhanced mineralized nodule formation; and increased the expression of odontoblastic markers including dentin sialophosphoprotein, dentin matrix protein 1, runt-related transcription factor 2, and osteocalcin. Moreover, pretreatment with Compound C, a specific AMPK inhibitor, markedly reversed metformin-induced odontoblastic differentiation and cell mineralization. CONCLUSIONS This study shows that metformin can induce DPC differentiation and mineralization in an AMPK-dependent manner and that this well-tolerated antidiabetic drug has potential in regenerative endodontics as well as in other regenerative applications.
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Affiliation(s)
- Wei Qin
- Department of Operative Dentistry and Endodontics, Guanghua School of Stomatology, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Stomatology, Guangzhou, China; Department of Advanced Oral Sciences and Therapeutics, University of Maryland School of Medicine, Baltimore, Maryland
| | - Xianling Gao
- Department of Operative Dentistry and Endodontics, Guanghua School of Stomatology, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Stomatology, Guangzhou, China; Department of Advanced Oral Sciences and Therapeutics, University of Maryland School of Medicine, Baltimore, Maryland
| | - Tao Ma
- Department of Oncology and Diagnostic Sciences, University of Maryland School of Medicine, Baltimore, Maryland
| | - Michael D Weir
- Department of Advanced Oral Sciences and Therapeutics, University of Maryland School of Medicine, Baltimore, Maryland
| | - Jing Zou
- Department of Oncology and Diagnostic Sciences, University of Maryland School of Medicine, Baltimore, Maryland
| | - Bing Song
- Department of Advanced Oral Sciences and Therapeutics, University of Maryland School of Medicine, Baltimore, Maryland
| | - Zhengmei Lin
- Department of Operative Dentistry and Endodontics, Guanghua School of Stomatology, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Stomatology, Guangzhou, China.
| | - Abraham Schneider
- Department of Oncology and Diagnostic Sciences, University of Maryland School of Medicine, Baltimore, Maryland.
| | - Hockin H K Xu
- Department of Advanced Oral Sciences and Therapeutics, University of Maryland School of Medicine, Baltimore, Maryland; Center for Stem Cell Biology and Regenerative Medicine, University of Maryland School of Medicine, Baltimore, Maryland; Department of Mechanical Engineering, University of Maryland, Baltimore County, Baltimore County, Maryland.
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17
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Alcohol Inhibits Odontogenic Differentiation of Human Dental Pulp Cells by Activating mTOR Signaling. Stem Cells Int 2017; 2017:8717454. [PMID: 29062364 PMCID: PMC5618757 DOI: 10.1155/2017/8717454] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2017] [Revised: 07/05/2017] [Accepted: 07/16/2017] [Indexed: 12/19/2022] Open
Abstract
Long-term heavy alcohol consumption could result in a range of health, social, and behavioral problems. People who abuse alcohol are at high risks of seriously having osteopenia, periodontal disease, and compromised oral health. However, the role of ethanol (EtOH) in the biological functions of human dental pulp cells (DPCs) is unknown. Whether EtOH affects the odontoblastic differentiation of DPCs through the mechanistic target of rapamycin (mTOR) remains unexplored. The objective of this study was to investigate the effects of EtOH on DPC differentiation and mineralization. DPCs were isolated and purified from human dental pulps. The proliferation and odontoblastic differentiation of DPCs treated with EtOH were subsequently investigated. Different doses of EtOH were shown to be cytocompatible with DPCs. EtOH significantly activated the mTOR pathway in a dose-dependent manner. In addition, EtOH downregulated the alkaline phosphatase activity, attenuated the mineralized nodule formation, and suppressed the expression of odontoblastic markers including ALP, DSPP, DMP-1, Runx2, and OCN. Moreover, the pretreatment with rapamycin, a specific mTOR inhibitor, markedly reversed the EtOH-induced odontoblastic differentiation and cell mineralization. Our findings show for the first time that EtOH can suppress DPC differentiation and mineralization in a mTOR-dependent manner, indicating that EtOH may be involved in negatively regulating the dental pulp repair.
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18
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Sagomonyants K, Kalajzic I, Maye P, Mina M. FGF Signaling Prevents the Terminal Differentiation of Odontoblasts. J Dent Res 2017; 96:663-670. [PMID: 28170285 DOI: 10.1177/0022034517691732] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Members of the fibroblast growth factor (FGF) family play essential and important roles in primary and reparative dentinogenesis, with conflicting results regarding their effects on odontoblast differentiation. Our recent studies showed that the effects of FGF2 on cells in odontoblast lineage were stage-specific and depended on the stage of cell maturity. Continuous exposure of pulp cells to FGF2 inhibited odontoblast differentiation, whereas early and limited exposure of pulp cells to FGF2 resulted in marked increases in odontoblast differentiation. The purpose of this study was to evaluate the cellular and molecular mechanisms regulating the inhibitory effects of FGF2 on odontoblast differentiation. To do so, we examined the effects of the addition of FGF2 during the differentiation/mineralization phase of the in vitro growth of pulp cultures derived from a series of green fluorescent protein reporter transgenic mice that display stage-specific activation of transgenes during odontoblast differentiation. Our results showed that this treatment first stimulated the differentiation of remaining progenitors in pulp cultures into functional odontoblasts but prevented their differentiation into mature odontoblasts. In addition, this treatment inhibited expression of markers of osteogenesis. Furthermore, we demonstrated that the inhibitory effects of FGF2 on odontoblast differentiation were mediated through activation of FGFR/MEK/Erk1/2 signaling and downregulation of bone morphogenetic protein signaling, with negative and positive roles in the expression of Dmp1 and Dspp, respectively, during the advanced stage of odontoblast differentiation.
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Affiliation(s)
- K Sagomonyants
- 1 Department of Oral Health and Diagnostic Sciences, School of Dental Medicine, University of Connecticut Health Center, Farmington, CT, USA
| | - I Kalajzic
- 2 Department of Reconstructive Sciences, School of Dental Medicine, University of Connecticut Health Center, Farmington, CT, USA
| | - P Maye
- 2 Department of Reconstructive Sciences, School of Dental Medicine, University of Connecticut Health Center, Farmington, CT, USA
| | - M Mina
- 3 Department of Craniofacial Sciences, School of Dental Medicine, University of Connecticut Health Center, Farmington, CT, USA
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19
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Sagomonyants K, Kalajzic I, Maye P, Mina M. Enhanced Dentinogenesis of Pulp Progenitors by Early Exposure to FGF2. J Dent Res 2015; 94:1582-90. [PMID: 26276371 DOI: 10.1177/0022034515599768] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Members of the fibroblast growth factor (FGF) family play essential and important roles in primary and reparative dentinogenesis. Although there appears to be a general agreement on the effects of FGF signaling on the proliferation of pulp cells, there are conflicting results regarding its effects on odontoblast differentiation. We recently examined the effects of continuous exposure of dental pulp cells to FGF2 and showed that the effects of FGF2 on differentiation of progenitor cells into odontoblasts were stage specific and dependent on the stage of cell maturity. The purpose of this study was to gain further insight into cellular and molecular mechanisms regulating the stimulatory effects of FGF2 on odontoblast differentiation. To do so, we examined the effects of early and limited exposure of pulp cells from a series of green fluorescent protein (GFP) reporter transgenic mice that display stage-specific activation of transgenes during odontoblast differentiation to FGF2. Our results showed that early and limited exposure of pulp cells to FGF2 did not have significant effects on the extent of mineralization but induced significant increases in the expression of Dmp1 and Dspp and the number of DMP1-GFP(+) and DSPP-Cerulean(+) odontoblasts. Our results also showed that the stimulatory effects of FGF2 on odontoblast differentiation were mediated through FGFR/MEK/Erk1/2 signaling, increases in Bmp2, and activation of the BMP/BMPR signaling pathway. These observations show that early and limited exposure of pulp cells to FGF2 alone promotes odontoblast differentiation and provides critical insight for applications of FGF2 in dentin regeneration.
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Affiliation(s)
- K Sagomonyants
- Department of Craniofacial Sciences, School of Dental Medicine, University of Connecticut Health Center, Farmington, CT, USA
| | - I Kalajzic
- Department of Reconstructive Sciences, School of Dental Medicine, University of Connecticut Health Center, Farmington, CT, USA
| | - P Maye
- Department of Reconstructive Sciences, School of Dental Medicine, University of Connecticut Health Center, Farmington, CT, USA
| | - M Mina
- Department of Craniofacial Sciences, School of Dental Medicine, University of Connecticut Health Center, Farmington, CT, USA
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Kamel-ElSayed SA, Tiede-Lewis LM, Lu Y, Veno PA, Dallas SL. Novel approaches for two and three dimensional multiplexed imaging of osteocytes. Bone 2015; 76:129-40. [PMID: 25794783 PMCID: PMC4591054 DOI: 10.1016/j.bone.2015.02.011] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/04/2014] [Revised: 02/02/2015] [Accepted: 02/02/2015] [Indexed: 01/20/2023]
Abstract
Although osteocytes have historically been viewed as quiescent cells, it is now clear that they are highly active cells in bone and play key regulatory roles in diverse skeletal functions, including mechanotransduction, phosphate homeostasis and regulation of osteoblast and osteoclast activity. Three dimensional imaging of embedded osteocytes and their dendritic connections within intact bone specimens can be quite challenging and many of the currently available methods are actually imaging the lacunocanalicular network rather than the osteocytes themselves. With the explosion of interest in the field of osteocyte biology, there is an increased need for reliable ways to image these cells in live and fixed bone specimens. Here we report the development of reproducible methods for 2D and 3D imaging of osteocytes in situ using multiplexed imaging approaches in which the osteocyte cell membrane, nucleus, cytoskeleton and extracellular matrix can be imaged simultaneously in various combinations. We also present a new transgenic mouse line expressing a membrane targeted-GFP variant selectively in osteocytes as a novel tool for in situ imaging of osteocytes and their dendrites in fixed or living bone specimens. These methods have been multiplexed with a novel method for labeling of the lacunocanalicular network using fixable dextran, which enables aspects of the osteocyte cell structure and lacunocanalicular system to be simultaneously imaged. The application of these comprehensive approaches for imaging of osteocytes in situ should advance research into osteocyte biology and function in health and disease.
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Affiliation(s)
- Suzan A Kamel-ElSayed
- Department of Oral and Craniofacial Sciences, School of Dentistry, University of Missouri, Kansas City, 615 E. 25th Street, Kansas City, MO 64108, USA; Biomedical Sciences Department, Oakland University William Beaumont School of Medicine, 414 O'Dowd Hall, Rochester MI, 48309, USA; Medical Physiology Department, Assiut University School of Medicine, 71516 Asyut, Egypt
| | - LeAnn M Tiede-Lewis
- Department of Oral and Craniofacial Sciences, School of Dentistry, University of Missouri, Kansas City, 615 E. 25th Street, Kansas City, MO 64108, USA
| | - Yongbo Lu
- Department of Oral and Craniofacial Sciences, School of Dentistry, University of Missouri, Kansas City, 615 E. 25th Street, Kansas City, MO 64108, USA; Department of Biomedical Sciences, Texas A&M University Baylor College of Dentistry, 3302 Gaston Ave., Dallas, TX 75246, USA
| | - Patricia A Veno
- Department of Oral and Craniofacial Sciences, School of Dentistry, University of Missouri, Kansas City, 615 E. 25th Street, Kansas City, MO 64108, USA
| | - Sarah L Dallas
- Department of Oral and Craniofacial Sciences, School of Dentistry, University of Missouri, Kansas City, 615 E. 25th Street, Kansas City, MO 64108, USA.
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Sagomonyants K, Mina M. Stage-specific effects of fibroblast growth factor 2 on the differentiation of dental pulp cells. Cells Tissues Organs 2015; 199:311-28. [PMID: 25823776 DOI: 10.1159/000371343] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/04/2014] [Indexed: 12/31/2022] Open
Abstract
Dentinogenesis is a complex and multistep process, which is regulated by various growth factors, including members of the fibroblast growth factor (FGF) family. Both positive and negative effects of FGFs on dentinogenesis have been reported, but the underlying mechanisms of these conflicting results are still unclear. To gain a better insight into the role of FGF2 in dentinogenesis, we used dental pulp cells from various transgenic mice, in which fluorescent protein expression identifies cells at different stages of odontoblast differentiation. Our results showed that the continuous exposure of pulp cells to FGF2 inhibited mineralization and revealed both the stimulatory and inhibitory effects of FGF2 on the expression of markers of dentinogenesis and various transgenes. During the proliferation phase of in vitro growth, FGF2 increased the expression of markers of dentinogenesis and the percentages of dentin matrix protein 1/green fluorescent protein (DMP1-GFP)-positive functional odontoblasts and dentin sialophosphoprotein (DSPP)-Cerulean-positive odontoblasts. Additional exposure to FGF2 during the differentiation/mineralization phase of in vitro growth decreased the extent of mineralization and the expression of markers of dentinogenesis and of the DMP1-GFP and DSPP-Cerulean transgenes. Recovery experiments showed that the inhibitory effects of FGF2 on dentinogenesis were related to the blocking of the differentiation of cells into mature odontoblasts. These observations together showed the stage-specific effects of FGF2 on dentinogenesis by dental pulp cells, and they provide critical information for the development of improved treatments for vital pulp therapy and dentin regeneration.
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Affiliation(s)
- Karen Sagomonyants
- Department of Craniofacial Sciences, School of Dental Medicine, University of Connecticut Health Center, Farmington, Conn., USA
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22
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Chia LY, Walsh NC, Martin TJ, Sims NA. Isolation and gene expression of haematopoietic-cell-free preparations of highly purified murine osteocytes. Bone 2015; 72:34-42. [PMID: 25460578 DOI: 10.1016/j.bone.2014.11.005] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/14/2014] [Revised: 10/14/2014] [Accepted: 11/11/2014] [Indexed: 10/24/2022]
Abstract
To define their gene expression and function, osteocytes are commonly isolated and purified by fluorescence-activated cell sorting (FACS) from mice expressing GFP directed by the dentin matrix protein 1 (Dmp1) promoter (DMP1-GFP). These cells express mRNA for osteocyte genes, including sclerostin (Sost) and Dmp1, and genes associated with the osteoclast phenotype: Dcstamp, Oscar, Cathepsin K (Ctsk), tartrate resistant acid phosphatase (TRAP/Acp5) and calcitonin receptor (Calcr). This suggests either that osteoclasts and osteocytes share genes and functions or that DMP1-GFP(+) preparations contain haematopoietic osteoclasts. To resolve this we stained DMP1-GFP cells for haematopoietic lineage (Lin) surface markers (CD2, CD3e, CD4, CD45, CD5, CD8, CD11b, B220, Gr1, Ter119) and CD31. Lin(-)CD31(-) (Lin(-)) and Lin(+)CD31(+) (Lin(+)) populations were analysed for GFP, and the four resulting populations assessed by quantitative real-time PCR. Lin(-)GFP(+) cells expressed mRNAs for Sost, Dmp1, and Mepe, confirming their osteocyte identity. Dcstamp and Oscar mRNAs were restricted to haematopoietic (Lin(+)) cells, but Calcr, Ctsk and Acp5 were readily detected in purified osteocytes (Lin(-)GFP(+)). The capacity of these purified osteocytes to support osteoclastogenesis was assessed: no TRAP+ cells with >2 nuclei were formed when purified osteocytes were cultured with bone marrow macrophages and stimulated with 1,25-dihydroxyvitamin-D3/prostaglandin E2. Lin(-)GFP(+) osteocytes also expressed lower levels of Tnfsf11 (RANKL) mRNA than the osteoblast-enriched population (Lin(-)GFP(-)). This demonstrates the importance of haematopoietic depletion in generating highly purified osteocytes and shows that osteocytes express Acp5, Ctsk and Calcr, but not other osteoclast markers, and do not fully support osteoclast formation in vitro.
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Affiliation(s)
- Ling Yeong Chia
- St. Vincent's Institute of Medical Research, Fitzroy, Victoria, Australia; Department of Medicine at St. Vincent's Hospital, The University of Melbourne, Fitzroy, Victoria, Australia
| | - Nicole C Walsh
- St. Vincent's Institute of Medical Research, Fitzroy, Victoria, Australia; Department of Medicine at St. Vincent's Hospital, The University of Melbourne, Fitzroy, Victoria, Australia
| | - T John Martin
- St. Vincent's Institute of Medical Research, Fitzroy, Victoria, Australia; Department of Medicine at St. Vincent's Hospital, The University of Melbourne, Fitzroy, Victoria, Australia
| | - Natalie A Sims
- St. Vincent's Institute of Medical Research, Fitzroy, Victoria, Australia; Department of Medicine at St. Vincent's Hospital, The University of Melbourne, Fitzroy, Victoria, Australia.
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Qin W, Liu P, Zhang R, Huang S, Gao X, Song Z, Wang R, Chen L, Guo B, Lin Z. JNK MAPK is involved in BMP-2-induced odontoblastic differentiation of human dental pulp cells. Connect Tissue Res 2014; 55:217-24. [PMID: 24409810 DOI: 10.3109/03008207.2014.882331] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Bone morphogenetic protein-2 (BMP-2) is a multi-functional growth factor belonging to the transforming growth factor β superfamily that has a broad range of activities that affect many different cell types. BMP-2 induces odontoblastic differentiation of human dental pulp cells (DPCs), but the underlying mechanism remains unclear. In this study, we investigated the potential role of the JNK mitogen-activated protein kinases (MAPK) pathway in BMP-2-induced odontoblastic differentiation of DPCs. The levels of phosphorylated and unphosphorylated JNK MAPK were quantified by Western blot analysis following treatment with BMP-2 and the JNK inhibitor SP600125. The role of JNK MAPK in the BMP-2-induced odontoblastic differentiation of DPCs was determined by measuring alkaline phosphatase (ALP) activity and by examining the expression of odontoblastic markers using quantitative real-time polymerase chain reaction analysis. The effect of JNK MAPK silencing on odontoblastic differentiation was also investigated. BMP-2 upregulated the phosphorylation of JNK in DPCs in a dose- and time-dependent manner. Early markers of odontoblastic differentiation, including ALP activity, osteopontin and dentin matrix protein-1, were not inhibited by the JNK inhibitor. However, the JNK inhibitor, SP600125, significantly inhibited late-stage differentiation of odontoblasts, including the gene expression of osteocalcin, dentin sialophosphoprotein and bone sialoprotein, and also reduced the formation of mineralized nodules in BMP-2-treated DPCs. Consistent with this observation, silencing of JNK MAPK also decreased late-stage odontoblastic differentiation. Taken together, these findings suggest that JNK activity is required for late-stage odontoblastic differentiation induced by BMP-2.
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Affiliation(s)
- Wei Qin
- Department of Operative Dentistry and Endodontics, Guanghua School of Stomatology, Hospital of Stomatology, Sun Yat-sen University , Guangzhou , China
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Abstract
Odontoblasts are dentin-secreting cells that survive for the whole life of a healthy tooth. Once teeth are completely erupted, odontoblasts transform into a mature stage that allows for their functional conservation for decades, while maintaining the capacity for secondary and reactionary dentin secretion. Odontoblasts are also critically involved in the transmission of sensory stimuli from the dentin-pulp complex and in the cellular defense against pathogens. Their longevity is sustained by an elaborate autophagic-lysosomal system that ensures organelle and protein renewal. However, progressive dysfunction of this system, in part caused by lipofuscin accumulation, reduces the fitness of odontoblasts and eventually impairs their dentin maintenance capacity. Here we review the functional activities assumed by mature odontoblasts throughout life. Understanding the biological basis of age-related changes in human odontoblasts is crucial to improving tooth preservation in the elderly.
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Affiliation(s)
- E. Couve
- Departamento de Biología, Laboratorio de Microscopía Electrónica
- Facultad de Ciencias, Universidad de Valparaíso, Avda. Gran Bretaña 1111, Playa Ancha, Valparaíso, Chile
| | - R. Osorio
- Departamento de Biología, Laboratorio de Microscopía Electrónica
- Facultad de Ciencias, Universidad de Valparaíso, Avda. Gran Bretaña 1111, Playa Ancha, Valparaíso, Chile
| | - O. Schmachtenberg
- Centro Interdisciplinario de Neurociencia de Valparaíso (CINV)
- Facultad de Ciencias, Universidad de Valparaíso, Avda. Gran Bretaña 1111, Playa Ancha, Valparaíso, Chile
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Frozoni M, Balic A, Sagomonyants K, Zaia AA, Line SRP, Mina M. A feasibility study for the analysis of reparative dentinogenesis in pOBCol3.6GFPtpz transgenic mice. Int Endod J 2012; 45:907-14. [PMID: 22551423 DOI: 10.1111/j.1365-2591.2012.02047.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
AIM To examine the feasibility of using the pOBCol3.6GFPtpz [3.6-green fluorescent protein (GFP)] transgenic mice as an in vivo model for studying the biological sequence of events during pulp healing and reparative dentinogenesis. METHODOLOGY Pulp exposures were created in the first maxillary molar of 12-16-week-old 3.6-GFP transgenic mice with CD1 and C57/Bl6 genetic background. Direct pulp capping on exposed teeth was performed using mineral trioxide aggregate followed by restoration with a light-cured adhesive system (AS) and composite resin. In control teeth, the AS was placed in direct contact with the pulp. Animals were euthanized at various time points after pulp exposure and capping. The maxillary arch was isolated, fixed and processed for histological and epifluorescence analysis to examine reparative dentinogenesis. RESULTS Analysis of teeth immediately after pulp exposure revealed absence of odontoblasts expressing 3.6-GFP at the injury site. Evidence of reparative dentinogenesis was apparent at 4 weeks in 3.6-GFP mice in CD1 background and at 8 weeks in 3.6-GFP mice with C57/Bl6 background. The reparative dentine with both groups contained newly formed atubular-mineralized tissue resembling a dentine bridge and/or osteodentine that was lined by cells expressing 3.6-GFP as well as 3.6-GFP expressing cells embedded within the atubular matrix. CONCLUSION This study was conducted in a few animals and did not allow statistical analysis. The results revealed that the 3.6-GFP transgenic animals provide a unique model for direct analysis of cellular and molecular mechanisms of pulp repair and tertiary dentinogenesis in vivo. The study also shows the effects of the capping material and the genetic background of the mice in the sequence and timing of reparative dentinogenesis.
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Affiliation(s)
- M Frozoni
- Division of Endodontics, Department of Restorative Dentistry, Piracicaba Dental School, University of Campinas, São Paulo, Brazil
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Ruan GP, Wang JX, Pang RQ, Yao X, Cai XM, Wang Q, Ma LH, Zhu XQ, Pan XH. Treatment with chicken-egg-white or whole-egg extracts maintains and enhances the survival and differentiation of spleen cells. Cytotechnology 2012; 64:541-51. [PMID: 22350684 DOI: 10.1007/s10616-012-9431-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2011] [Accepted: 01/18/2012] [Indexed: 12/26/2022] Open
Abstract
The identification of egg extracts with the ability to maintain and enhance the survival and differentiation of cells would be widely useful in cellular biology research. In this study, we compared the different abilities of spleen cells to survive and differentiate in vivo after permeabilization by five different types of egg extracts. Five types of egg extracts were prepared. The spleen cells from male GFP-transgenic mice were permeabilized by the extracts for 30 min, cultured for 12 days, and then transfused into irradiated female mice. At varying days after transplantation, the percentage of GFP-expressing surviving spleen cells was detected in the peripheral blood by flow cytometry. At 120 days after transplantation, bone marrow cells from the female mice were analyzed for the presence of cells containing the Y chromosome. Surviving GFP-positive spleen cells that had been permeabilized with either chicken-egg-white or whole-egg extracts could be detected in the female mice after transplantation. A lower percentage of GFP-positive cells was also detected after permeabilization by the other extracts tested, and no GFP-positive cells were found in the female mouse transfused with spleen cells permeabilized with Hank's Buffered Salt Solution (HBSS) as a control. At 120 days after transplantation, the percentage of cells containing a Y chromosome in the bone marrow positively correlated with the percentage of GFP-positive cells in the peripheral blood. After permeabilization by chicken-egg-white or whole-egg extracts, spleen cells demonstrated significantly enhanced survival and differentiation functions compared with the spleen cells treated with the other egg extracts tested. These results show that chicken-egg-white and whole-egg extracts have roles in maintaining and enhancing the survival and differentiation of spleen cells. Therefore, these two types of extracts may be of future use in maintaining the function of stem cells.
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Affiliation(s)
- Guang-Ping Ruan
- Research Center of Stem Cell, Tissue and Organ Engineering, Kunming General Hospital of PLA, Kunming, 650032, China
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