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Stem Cells and Development Jun 2020Stem cells derived from dental apical papilla (SCAPs) can secrete various soluble factors, which may stimulate tissue repair and regeneration in vivo. The aim of this...
Effect of the Soluble Factors Released by Dental Apical Papilla-Derived Stem Cells on the Osteo/Odontogenic, Angiogenic, and Neurogenic Differentiation of Dental Pulp Cells.
Stem cells derived from dental apical papilla (SCAPs) can secrete various soluble factors, which may stimulate tissue repair and regeneration in vivo. The aim of this study was to elucidate the effect of the soluble factors released by SCAPs on the proliferation and differentiation of dental pulp cells (DPCs). We compared the osteo/odontogenic, angiogenic, and neurogenic effects of soluble factors released from SCAPs and bone marrow mesenchymal stem cells (BMSCs) in vitro. Conditioned media (CM) were collected from human SCAPs and BMSCs cultures, and their effects on human DPCs proliferation and differentiation were evaluated. Cellular proliferation was unaffected by SCAPs-CM and was inhibited by BMSCs-CM. Cells treated with osteo/odontogenic inducing medium (OM) plus SCAPs-CM showed higher alkaline phosphatase activity than did cells in the OM group. The expression level of osteo/odontogenic markers were higher in the SCAPs-CM plus OM group than in the BMSCs-CM plus OM and OM groups. SCAPs-CM and BMSCs-CM significantly promoted DPCs migration. DPCs angiogenic differentiation was not affected by SCAPs-CM but was significantly enhanced by BMSCs-CM. In DPCs cultured in media optimized for neural stem cell growth for 2 weeks, the expression levels of neurogenic markers were significantly enhanced by the addition of SCAPs-CM. Neuronal markers expression was significantly reduced, while neurotrophic marker expression significantly increased by the addition of BMSCs-CM. In conclusion, SCAPs-CM significantly enhanced osteo/odontogenic differentiation, migration, and neurogenic differentiation potential of DPCs, but have no effect on DPCs proliferation and angiogenic differentiation in vitro. CM released from SCAPs have a greater osteo/odontogenic and neurogenic inductive effect on DPCs than BMSCs-CM. It indicates that SCAPs-CM can serve as additive to improve pulp tissue repair and regeneration.
Topics: Adolescent; Adult; Cell Differentiation; Cell Proliferation; Cells, Cultured; Culture Media, Conditioned; Dental Papilla; Dental Pulp; Endothelial Cells; Humans; Mesenchymal Stem Cells; Neovascularization, Physiologic; Neural Stem Cells; Osteoblasts; Osteogenesis
PubMed: 32178575
DOI: 10.1089/scd.2019.0262 -
Journal of Molecular Histology Jun 2019Interactions between the ectodermal and mesenchymal tissues are the basis of the central mechanism regulating tooth development. Based on this epithelial-mesenchymal...
Interactions between the ectodermal and mesenchymal tissues are the basis of the central mechanism regulating tooth development. Based on this epithelial-mesenchymal interaction (EMI), we demonstrated that copine-7 (CPNE7) is secreted by preameloblasts and regulates the differentiation of mesenchymal cells of dental or non-dental origin into odontoblasts. However, the precise expression patterns of CPNE7 in the stages of tooth development have not yet been elucidated. The aim of the present study was to establish the spatiotemporal expression pattern of CPNE7 during mouse tooth development. To examine the spatiotemporal expression patterns of CPNE7 during mouse tooth development, we investigate the distribution of CPNE7 in the embryonic and postnatal developing mouse tooth. Immunohistochemistry, in situ hybridization, real-time PCR, and western blot analysis are performed to investigate the CPNE7 expression pattern during tooth development of the mandibular mouse first molar. During the initiation stage (bud stage), CPNE7 protein expression is observed in the dental epithelium but not yet in the dental mesenchyme. At E18 (bell stage), expression of CPNE7 protein and mRNA is primarily observed in ectomesenchymal cells of dental papilla. At P7 (crown formation stage), CPNE7 is localized in differentiating odontoblasts but weak expression is detected in mature ameloblasts. These findings suggest that CPNE7 secreted by dental epithelium induces the differentiation of ectomesenchymal cells into preodontoblast in concert with EMI. CPNE7 is clearly expressed in differentiating odontoblasts and the odontoblast process during dentinogenesis, but is no longer expressed in fully differentiated odontoblasts. Furthermore, CPNE7 is expressed in the Hertwig's epithelial root sheath (HERS) and in the facing preodontoblasts during root dentin formation. Taken together, these results illustrate the dynamic expression of CPNE7 during tooth development and suggest its important function in entire stages of tooth development.
Topics: Ameloblasts; Animals; Cell Differentiation; Dental Papilla; Dentinogenesis; Gene Expression Regulation, Developmental; Membrane Proteins; Mice; Molar; Odontoblasts; Tooth
PubMed: 30863901
DOI: 10.1007/s10735-019-09816-0 -
International Journal of Oral Science Apr 2022Multiple signaling pathways are involved in the regulation of cell proliferation and differentiation in odontogenesis and dental tissue renewal, but the details of these...
Multiple signaling pathways are involved in the regulation of cell proliferation and differentiation in odontogenesis and dental tissue renewal, but the details of these mechanisms remain unknown. Here, we investigated the expression patterns of a transcription factor, Krüppel-like factor 6 (KLF6), during the development of murine tooth germ and its function in odontoblastic differentiation. KLF6 was almost ubiquitously expressed in odontoblasts at various stages, and it was co-expressed with P21 (to varying degrees) in mouse dental germ. To determine the function of Klf6, overexpression and knockdown experiments were performed in a mouse dental papilla cell line (iMDP-3). Klf6 functioned as a promoter of odontoblastic differentiation and inhibited the proliferation and cell cycle progression of iMDP-3 through p21 upregulation. Dual-luciferase reporter assay and chromatin immunoprecipitation showed that Klf6 directly activates p21 transcription. Additionally, the in vivo study showed that KLF6 and P21 were also co-expressed in odontoblasts around the reparative dentin. In conclusion, Klf6 regulates the transcriptional activity of p21, thus promoting the cell proliferation to odontoblastic differentiation transition in vitro. This study provides a theoretical basis for odontoblast differentiation and the formation of reparative dentine regeneration.
Topics: Animals; Cell Differentiation; Cell Proliferation; Mice; Odontoblasts; Odontogenesis; Tooth Germ
PubMed: 35422483
DOI: 10.1038/s41368-022-00172-6 -
Developmental Dynamics : An Official... Jul 2021Organs that develop early in life, and are replaced by a larger version as the animal grows, often represent a miniature version of the adult organ. Teeth constituting...
BACKGROUND
Organs that develop early in life, and are replaced by a larger version as the animal grows, often represent a miniature version of the adult organ. Teeth constituting the first functional dentition in small-sized teleost fish, such as medaka (Oryzias latipes), are examples of such miniature organs. With a dentin cone as small as the size of one human cell, or even smaller, these teeth raise the question how many dentin-producing cells (odontoblasts) are required to build such a tooth, and whether this number can be as little as one.
RESULTS
Based on detailed observations with transmission electron microscopy (TEM) and TEM-based 3D-reconstructions, we show that only one mesenchymal cell qualifies as a true odontoblast. A second mesenchymal cell potentially participates in dentin formation, but only at a late stage of tooth development. Moreover, the fate of these cells appears to be specified very early during tooth development.
CONCLUSIONS
Our observations indicate that in this system, one single odontoblast fulfills roles normally exerted by a large and communicating cell population. First-generation teeth in medaka thus provide an exciting model to study integration of multiple functions into a single cell.
Topics: Animals; Cell Count; Cell Differentiation; Cell Lineage; Computer Simulation; Embryo, Nonmammalian; Imaging, Three-Dimensional; Mesenchymal Stem Cells; Miniaturization; Morphogenesis; Odontoblasts; Odontogenesis; Oryzias; Tooth; Tooth Eruption
PubMed: 33452709
DOI: 10.1002/dvdy.300 -
Journal of Dental Research Jan 2018Lineage-committed differentiation is an essential biological program during odontogenesis, which is tightly regulated by lineage-specific genes. Some of these genes are...
Lineage-committed differentiation is an essential biological program during odontogenesis, which is tightly regulated by lineage-specific genes. Some of these genes are modified by colocalization of H3K4me3 and H3K27me3 marks at promoter regions in progenitors. These modifications, named "bivalent domains," maintain genes in a poised state and then resolve for later activation or repression during differentiation. Wnt5a has been reported to promote odontogenic differentiation in dental mesenchyme. However, relatively little is known about the epigenetic modulations on Wnt5a activation during tooth development. Here, we investigated the spatiotemporal patterns of H3K4me3 and H3K27me3 marks in developing mouse molars. Associated H3K4me3 methylases (mixed-lineage leukemia [MLL] complex) and H3K27me3 demethylases (JMJD3 and UTX) were dynamically expressed between early and late bell stage of human tooth germs and in cultured human dental papilla cells (hDPCs) during odontogenic induction. Poised WNT5A gene was marked by bivalent domains containing repressive marks (H3K27me3) and active marks (H3K4me3) on promoters. The bivalent domains tended to resolve during inducted differentiation, with removal of the H3K27me3 mark in a JMJD3-dependent manner. When JMJD3 was knocked down in cultured hDPCs, odontogenic differentiation was suppressed. The depletion of JMJD3 epigenetically repressed WNT5A activation by increased H3K27me3 marks. In addition, JMJD3 could physically interact with ASH2L, a component of the MLL complex, to form a coactivator complex, cooperatively modulating H3K4me3 marks on WNT5A promoters. Overall, our study reveals that transcription activities of WNT5A were epigenetically regulated by the negotiated balance between H3K27me3 and H3K4me3 marks and tightly mediated by JMJD3 and MLL coactivator complex, ultimately modulating odontogenic commitment during dental mesenchymal cell differentiation.
Topics: Animals; Blotting, Western; Cells, Cultured; Chromatin Immunoprecipitation; Dental Papilla; Epigenesis, Genetic; Histone Code; Humans; Mesenchymal Stem Cells; Mice; Mice, Inbred BALB C; Molar; Odontogenesis; Real-Time Polymerase Chain Reaction; Wnt-5a Protein
PubMed: 28880717
DOI: 10.1177/0022034517728910 -
Cell Proliferation May 2019Nerous system diseases, both central and peripheral, bring an incredible burden onto patients and enormously reduce their quality of life. Currently, there are still no... (Review)
Review
Nerous system diseases, both central and peripheral, bring an incredible burden onto patients and enormously reduce their quality of life. Currently, there are still no effective treatments to repair nerve lesions that do not have side effects. Stem cell-based therapies, especially those using dental stem cells, bring new hope to neural diseases. Dental stem cells, derived from the neural crest, have many characteristics that are similar to neural cells, indicating that they can be an ideal source of cells for neural regeneration and repair. This review summarizes the neural traits of all the dental cell types, including DPSCs, PDLCs, DFCs, APSCs and their potential applications in nervous system diseases. We have summed up the advantages of dental stem cells in neural repair, such as their neurotrophic and neuroprotective traits, easy harvest and low rejective reaction rate, among others. Taken together, dental stem cells are an ideal cell source for neural tissue regeneration and repair.
Topics: Animals; Cell Differentiation; Dental Papilla; Dental Pulp; Dental Sac; Humans; Mesenchymal Stem Cell Transplantation; Mesenchymal Stem Cells; Nerve Regeneration; Nervous System Diseases; Neural Crest; Neural Stem Cells; Periodontal Ligament; Phenotype; Tooth; Trauma, Nervous System
PubMed: 30714230
DOI: 10.1111/cpr.12572 -
Journal of Endodontics Aug 2022Stem cells of the apical papilla (SCAP) play an important role in regenerative endodontic procedures (REPs). Previous studies have shown that during REPs, bacteria can...
INTRODUCTION
Stem cells of the apical papilla (SCAP) play an important role in regenerative endodontic procedures (REPs). Previous studies have shown that during REPs, bacteria can activate the innate immune system and cause indirect stem cell toxicity, leading to the lysis of SCAP. N-acetylcysteine (NAC)-treated cells are resistant to apoptosis and have increased differentiation capabilities. The immunomodulatory properties of NAC-treated SCAP are still unknown. Hence, the aim of this study is to evaluate the interactions of SCAP pretreated with and without NAC with the immune system.
METHODS
Flow cytometric analysis was performed to assess the effects of NAC on SCAP viability. Human SCAP were then cultured and were either pretreated with NAC or non-treated and co-cultured with human peripheral blood mononuclear cells. A lactate dehydrogenase assay was performed to evaluate the levels of immune cell mediated apoptosis, followed by an enzyme-linked immunosorbent assay (ELISA) to measure levels of proinflammatory cytokines for these co-cultures. Data were analyzed using analysis of variance with post hoc Tukey test.
RESULTS
Cells treated with NAC had similar levels of viability as the controls. SCAP pretreated with NAC had significantly lower immune cell-mediated cytotoxicity to nonactivated and activated peripheral blood mononuclear cells. The ELISA results showed that SCAP pretreated with NAC induced lower levels of proinflammatory cytokines.
CONCLUSIONS
SCAP pretreated with NAC have a higher chance of surviving the activated immune system. This information may provide a better insight into the properties of these stem cells and may be the key to making REPs more predictable.
Topics: Acetylcysteine; Cell Differentiation; Cytokines; Dental Papilla; Humans; Leukocytes, Mononuclear; Stem Cells
PubMed: 35588920
DOI: 10.1016/j.joen.2022.05.005 -
C-Jun N-terminal kinase (JNK) pathway activation is essential for dental papilla cells polarization.PloS One 2021During tooth development, dental papilla cells differentiate into odontoblasts with polarized morphology and cell function. Our previous study indicated that the C-Jun...
During tooth development, dental papilla cells differentiate into odontoblasts with polarized morphology and cell function. Our previous study indicated that the C-Jun N-terminal kinase (JNK) pathway regulates human dental papilla cell adhesion, migration, and formation of focal adhesion complexes. The aim of this study was to further examine the role of the JNK pathway in dental papilla cell polarity formation. Histological staining, qPCR, and Western Blot suggested the activation of JNK signaling in polarized mouse dental papilla tissue. After performing an in vitro tooth germ organ culture and cell culture, we found that JNK inhibitor SP600125 postponed tooth germ development and reduced the polarization, migration and differentiation of mouse dental papilla cells (mDPCs). Next, we screened up-regulated polarity-related genes during dental papilla development and mDPCs or A11 differentiation. We found that Prickle3, Golga2, Golga5, and RhoA were all up-regulated, which is consistent with JNK signaling activation. Further, constitutively active RhoA mutant (RhoA Q63L) partly rescued the inhibition of SP600125 on cell differentiation and polarity formation of mDPCs. To sum up, this study suggests that JNK signaling has a positive role in the formation of dental papilla cell polarization.
Topics: Animals; Anthracenes; Cell Differentiation; Cell Movement; Cell Polarity; Cells, Cultured; Dental Papilla; JNK Mitogen-Activated Protein Kinases; MAP Kinase Signaling System; Mice; Mice, Inbred ICR; Mutagenesis; Tooth Germ; rhoA GTP-Binding Protein
PubMed: 33770099
DOI: 10.1371/journal.pone.0233944 -
BioMed Research International 2019Stem cells are biological cells that can self-renew and can differentiate into multiple cell lineages. Stem cell-based therapy is emerging as a promising alternative... (Review)
Review
Stem cells are biological cells that can self-renew and can differentiate into multiple cell lineages. Stem cell-based therapy is emerging as a promising alternative therapeutic option for various disorders. Mesenchymal stem cells (MSCs) are multipotent adult stem cells that are isolated from various tissues and can be used as an alternative to embryonic stem cells. Stem cells from the apical papilla (SCAPs) are a novel population of MSCs residing in the apical papilla of immature permanent teeth. SCAPs present the characteristics of expression of MSCs markers, self-renewal, proliferation, migration, differentiation, and immunosuppression, which support the application of SCAPs in stem cell-based therapy, including the immunotherapy and the regeneration of dental tissues, bone, neural, and vascular tissues. In view of these properties and therapeutic potential, SCAPs can be considered as promising candidates for stem cell-based therapy. Thus the aim of our review was to summarize the current knowledge of SCAPs considering isolation, characterization, and multilineage differentiation. The prospects for their use in stem cell-based therapy were also discussed.
Topics: Cell Differentiation; Cell Lineage; Cell Proliferation; Dental Papilla; Humans; Mesenchymal Stem Cells; Multipotent Stem Cells; Osteogenesis; Stem Cell Transplantation
PubMed: 30834270
DOI: 10.1155/2019/6104738 -
BMC Oral Health Jan 2021Preservation of the interdental papilla is an essential part of the functional and esthetic rehabilitation of dental treatment. It has been described that thicker...
BACKGROUND
Preservation of the interdental papilla is an essential part of the functional and esthetic rehabilitation of dental treatment. It has been described that thicker gingival tissues are more resistant to recession. The main objective of this investigation was to analyze whether a thin gingival phenotype represents a potential risk indicator affecting interdental papilla fill, height, or width in an esthetic region between maxillary central incisors. The secondary goals were: (1) to analyze parameters describing the papilla-fill, height, width, and effect of papilla base width on the vertical papillary dimension; (2) to determine correlation between different non-invasive measurements of gingival thickness; (3) to compare both sexes.
METHODS
A total of 54 periodontally healthy students (20-30 years old) were included in the study. Gingival thickness was measured using Pirop Ultrasonic Biometer. Gingival phenotype was also assessed by gingival probe transparency. Papilla height and width were measured, and the degree of papilla recession was classified.
RESULTS
No significant relationship between papilla fill, height, width and gingival probe transparency or gingival thickness was found. Gingival thickness and gingival probe transparency showed a significant relationship (P < 0.001). There was a significant relationship between papilla height and papilla fill (P = 0.028). A papilla which filled the interdental space completely seemed to be shorter. A strong positive correlation between papilla height and papilla width was found (P < 0.0001). The papilla between maxillary central incisors was significantly higher in males (P = 0.01).
CONCLUSION
The appearance of the interdental papilla may be influenced by various factors. Within the limitations of this study, the results showed that the thin gingival phenotype alone is no potential risk indicator affecting interdental papilla fill, height, or width. It seems that there may be some effect of papilla base width on its vertical dimension. Gingival probe transparency is a simple reliable method of assessment of gingival thickness with a threshold value of 1-mm gingival thickness between the thick and thin phenotypes.
Topics: Adult; Esthetics, Dental; Female; Gingiva; Humans; Male; Maxilla; Odontometry; Phenotype; Young Adult
PubMed: 33485351
DOI: 10.1186/s12903-021-01400-x