Dental Pulp Stem Cells in Pulp Regeneration

Abstract Background: Dental pulp stem cells (DPSCs) have been developed as a potential source of mesenchymal stem cells (MSCs) for regeneration of dental pulp and other tissues. However, further strategies to isolate highly functional DPSCs beyond the colony-forming methods are required. Our clinical study has demonstrated safety and efficacy of DPSCs isolated by G-CSF-induced mobilization and cultured under normoxia (mobilized DPSCs, MDPSCs) for pulp regeneration. It is well known that the oxygen concentration is closely linked to the maintenance of stemness. Thus, in this investigation, hypoxia-preconditioned DPSCs (hpDPSCs) was characterized to develop and improve the clinical utility for regeneration of dental pulp in endodontics.Methods: Colony-forming DPSCs were isolated and preconditioned with hypoxia in a stable closed cultured system and compared with MDPSCs isolated from the individual dog teeth. We examined the proliferation rate, migration potential, anti-apoptotic activity and gene expression of the stem cell markers and angiogenic/neurotrophic factors. Trophic effects of the conditioned medium (CM) were also evaluated. In addition, the expression of immunomodulatory molecules upon stimulation with IFN-γ were investigated. The pulp regenerative potential and transplantation safety of hpDPSCs were further assessed in pulpectomized teeth in dogs by histological and immunohistochemical analyses and by chemistry of blood and urine. tests Results: hpDPSCs demonstrated higher proliferation rate and expression of a major regulator of oxygen homeostasis, HIF-1α, and a stem cell marker, CXCR-4. The direct migratory activity of hpDPSCs in response to G-CSF was significantly higher than MDPSCs. The CM of hpDPSCs stimulated neurite extension. However, there were no changes in angiogenic, migration and anti-apoptotic activities compared with the CM of MDPSCs. The expression of immunomodulatory gene, PTGE was significantly up-regulated by IFN gamma in hpDPSCs compared with MDPSCs. However, no difference in nitric oxide was observed. The regenerated pulp tissue was quantitatively and qualitatively similar in hpDPSC transplants compared with MDPSC transplants in dog teeth. There was no evidence of toxicity or adverse events of the hpDPSC transplantation Conclusions: These results demonstrated that hpDPSCs improved stem cell properties compared to MDPSCs, suggesting their potential clinical utility for pulp regeneration.

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Downregulation of miR-224-5p Promotes Migration and Proliferation in Human Dental Pulp Stem Cells

BioMed Research International ◽

10.1155/2019/4759060 ◽

2019 ◽

Vol 2019 ◽

pp. 1-8 ◽

Cited By ~ 2

Author(s):

Zhihong Ke ◽

Zailing Qiu ◽

Tingting Xiao ◽

Jianchai Zeng ◽

Luning Zou ◽

...

Keyword(s):

Stem Cells ◽

Root Canal ◽

Dental Pulp ◽

Dental Pulp Stem Cells ◽

Differentially Expressed ◽

Pulp Regeneration ◽

Regenerative Endodontics ◽

Differentially Expressed Mirna ◽

And Migration ◽

Proliferation And Migration

Introduction. Pulp regeneration, as a treatment for pulp necrosis, has significant advantages over root canal therapy for the preservation of living pulp. To date, research on pulp regeneration has mainly focused on the transplantation of pulp stem cells into the root canal, but there is still a lack of research on the migration of pulp cells into the root canal via cell homing. Stem cells from the apical tooth papilla (SCAP) are recognized as multidirectional stem cells, but these cells are difficult to obtain. MicroRNAs are small noncoding RNAs that play crucial roles in regulating normal and pathologic functions. We hypothesized that some types of microRNAs might improve the migration and proliferation function of dental pulp stem cells (DPSCs), which are easily obtained in clinical practice, and as a result, DPSCs might replace SCAP and provide valuable information for regenerative endodontics. Methods. Magnetic activated cell sorting of DPSCs and SCAP was performed. Next-generation sequencing was performed to examine DPSCs and SCAP miRNAs expression and to identify the most significant differentially expressed miRNA. CCK-8 and transwell assays were used to determine the impact of this miRNA on DPSCs proliferation and migration. Results. The most significant differentially expressed miRNA between DPSCs and SCAP was miR-224-5p. Downregulating miR-224-5p promoted DPSCs proliferation and migration; the opposite results were observed when miR-224-5p was upregulated. Conclusion. MiR-224-5p promotes proliferation and migration in DPSCs, a finding that is of great significance for further exploring the role of dental pulp stem cells in regenerative endodontics.

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Characterization of stable hypoxia-preconditioned dental pulp stem cells compared with mobilized dental pulp stem cells for application for pulp regenerative therapy

10.21203/rs.3.rs-102950/v2 ◽

2021 ◽

Author(s):

Mohammed Zayed ◽

Koichiro Iohara ◽

Hideto Watanabe ◽

Mami Ishikawa ◽

Michiyo Tominaga ◽

...

Keyword(s):

Stem Cells ◽

Stem Cell ◽

Dental Pulp ◽

Clinical Utility ◽

Dental Pulp Stem Cells ◽

Proliferation Rate ◽

Stem Cell Marker ◽

Stem Cell Markers ◽

Pulp Regeneration ◽

Potential Clinical Utility

Abstract Background: Dental pulp stem cells (DPSCs) have been developed as a potential source of mesenchymal stem cells (MSCs) for regeneration of dental pulp and other tissues. However, further strategies to isolate highly functional DPSCs beyond the colony-forming methods are required. We have demonstrated the safety and efficacy of DPSCs isolated by G-CSF-induced mobilization and cultured under normoxia (mobilized DPSCs, MDPSCs) for pulp regeneration. However, The device for isolation of MDPSCs, however, is not cost effective and requires prolonged cell culture period. It is well known that MSCs cultured under hypoxic-preconditions improved MSCs proliferation activity and stemness. Therefore, in this investigation, we attempted to improve the clinical utility of DPSCs by hypoxia-preconditioned DPSCs (hpDPSCs) compared with MDPSCs to improve the potential clinical utility for pulp regeneration in endodontic dentistry.Methods: Colony-forming DPSCs were isolated and preconditioned with hypoxia in a stable closed cultured system and compared with MDPSCs isolated from the individual dog teeth. We examined the proliferation rate, migration potential, anti-apoptotic activity and gene expression of the stem cell markers and angiogenic/neurotrophic factors. Trophic effects of the conditioned medium (CM) were also evaluated. In addition, the expression of immunomodulatory molecules upon stimulation with IFN-γ were investigated. The pulp regenerative potential and transplantation safety of hpDPSCs were further assessed in pulpectomized teeth in dogs by histological and immunohistochemical analyses and by chemistry of blood and urine tests. Results: hpDPSCs demonstrated higher proliferation rate and expression of a major regulator of oxygen homeostasis, HIF-1α, and a stem cell marker, CXCR-4. The direct migratory activity of hpDPSCs in response to G-CSF was significantly higher than MDPSCs. The CM of hpDPSCs stimulated neurite extension. However, there were no changes in angiogenic, migration and anti-apoptotic activities compared with the CM of MDPSCs. The expression of immunomodulatory gene, PTGE was significantly up-regulated by IFN gamma in hpDPSCs compared with MDPSCs. However, no difference in nitric oxide was observed. The regenerated pulp tissue was quantitatively and qualitatively similar in hpDPSC transplants compared with MDPSC transplants in dog teeth. There was no evidence of toxicity or adverse events of the hpDPSC transplantation. Conclusions: These results demonstrated that the efficacy of hpDPSCs for pulp regeneration was identical, although hpDPSCs improved stem cell properties compared to MDPSCs, suggesting their potential clinical utility for pulp regeneration.

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C5L2 Regulates DMP1 Expression during Odontoblastic Differentiation

Journal of Dental Research ◽

10.1177/0022034518820461 ◽

2019 ◽

Vol 98 (5) ◽

pp. 597-604 ◽

Cited By ~ 1

Author(s):

F. Chmilewsky ◽

R. Liang ◽

M. Kanazawa ◽

I. About ◽

L.F. Cooper ◽

...

Keyword(s):

Stem Cells ◽

Dental Pulp ◽

Matrix Protein ◽

Dental Pulp Stem Cells ◽

Negative Regulator ◽

Immunofluorescent Staining ◽

Stem Cell Markers ◽

C5a Receptor ◽

Pulp Regeneration ◽

Odontoblastic Differentiation

The presence of stem cells within the dental-pulp tissue as well as their differentiation into a new generation of functional odontoblast-like cells constitutes an important step of the dentin-pulp regeneration. Recent investigations demonstrated that the complement system activation participates in 2 critical steps of dentin-pulp regeneration: pulp progenitor’s recruitment and pulp nerve sprouting. Surprisingly, its implication in odontoblastic differentiation has not been addressed yet. Since the complement receptor C5a receptor-like 2 (C5L2) is expressed by different stem cells, the aim of this study is to investigate if the dental pulp stem cells express C5L2 and if this receptor participates in odontoblastic differentiation. Immunohistochemistry performed on human third molar pulp sections showed a perivascular co-localization of the mesenchymal stem cell markers STRO1 and C5L2. In vitro immunofluorescent staining confirmed that hDPSCs express C5L2. Furthermore, we determined by real-time polymerase chain reaction that the expression of C5L2 is highly modulated in human dental pulp stem cells (hDPSCs) undergoing odontoblastic differentiation. Moreover, we showed that this odontogenesis-regulated expression of C5L2 is specifically potentiated by the proinflammatory cytokine TNFα. Using a C5L2-siRNA silencing strategy, we provide direct evidence that C5L2 constitutes a negative regulator of the dentinogenic marker DMP1 (dentin matrix protein 1) expression by hDPSCs. Our findings suggest a direct correlation between the odontoblastic differentiation and the level of C5L2 expression in hDPSCs and identify C5L2 as a negative regulator of DMP1 expression by hDPSCs during the odontoblastic differentiation and inflammation processes. This work is the first to demonstrate the involvement of C5L2 in the biological function of stem cells, provides an important knowledge in understanding odontoblastic differentiation of dental pulp stem cells, and may be useful in future dentin-pulp engineering strategies.

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Characterization of stable hypoxia-preconditioned dental pulp stem cells compared with mobilized dental pulp stem cells for application for pulp regenerative therapy

Stem Cell Research & Therapy ◽

10.1186/s13287-021-02240-w ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Mohammed Zayed ◽

Koichiro Iohara ◽

Hideto Watanabe ◽

Mami Ishikawa ◽

Michiyo Tominaga ◽

...

Keyword(s):

Stem Cells ◽

Stem Cell ◽

Dental Pulp ◽

Clinical Utility ◽

Dental Pulp Stem Cells ◽

Proliferation Rate ◽

Stem Cell Marker ◽

Stem Cell Markers ◽

Pulp Regeneration ◽

Potential Clinical Utility

Abstract Background Dental pulp stem cells (DPSCs) have been developed as a potential source of mesenchymal stem cells (MSCs) for regeneration of dental pulp and other tissues. However, further strategies to isolate highly functional DPSCs beyond the colony-forming methods are required. We have demonstrated the safety and efficacy of DPSCs isolated by G-CSF-induced mobilization and cultured under normoxia (mobilized DPSCs, MDPSCs) for pulp regeneration. The device for isolation of MDPSCs, however, is not cost-effective and requires a prolonged cell culture period. It is well known that MSCs cultured under hypoxic-preconditions improved MSC proliferation activity and stemness. Therefore, in this investigation, we attempted to improve the clinical utility of DPSCs by hypoxia-preconditioned DPSCs (hpDPSCs) compared with MDPSCs to improve the potential clinical utility for pulp regeneration in endodontic dentistry. Methods Colony-forming DPSCs were isolated and preconditioned with hypoxia in a stable closed cultured system and compared with MDPSCs isolated from the individual dog teeth. We examined the proliferation rate, migration potential, anti-apoptotic activity, and gene expression of the stem cell markers and angiogenic/neurotrophic factors. Trophic effects of the conditioned medium (CM) were also evaluated. In addition, the expression of immunomodulatory molecules upon stimulation with IFN-γ was investigated. The pulp regenerative potential and transplantation safety of hpDPSCs were further assessed in pulpectomized teeth in dogs by histological and immunohistochemical analyses and by chemistry of the blood and urine tests. Results hpDPSCs demonstrated higher proliferation rate and expression of a major regulator of oxygen homeostasis, HIF-1α, and a stem cell marker, CXCR-4. The direct migratory activity of hpDPSCs in response to G-CSF was significantly higher than MDPSCs. The CM of hpDPSCs stimulated neurite extension. However, there were no changes in angiogenic, migration, and anti-apoptotic activities compared with the CM of MDPSCs. The expression of immunomodulatory gene, PTGE was significantly upregulated by IFN gamma in hpDPSCs compared with MDPSCs. However, no difference in nitric oxide was observed. The regenerated pulp tissue was quantitatively and qualitatively similar in hpDPSC transplants compared with MDPSC transplants in dog teeth. There was no evidence of toxicity or adverse events of the hpDPSC transplantation. Conclusions These results demonstrated that the efficacy of hpDPSCs for pulp regeneration was identical, although hpDPSCs improved stem cell properties compared to MDPSCs, suggesting their potential clinical utility for pulp regeneration.

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