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Journal of Biochemistry Jan 2022The dental pulp is critical for the production of odontoblasts to create reparative dentin. In recent years, dental pulp has become a promising source of mesenchymal...
The dental pulp is critical for the production of odontoblasts to create reparative dentin. In recent years, dental pulp has become a promising source of mesenchymal stem cells that are capable of differentiating into multiple cell types. To elucidate the transcriptional control mechanisms specifying the early phases of odontoblast differentiation, we analysed the DNA demethylation pattern associated with 5-hydroxymethylcytosine (5hmC) in the primary murine dental pulp. 5hmC plays an important role in chromatin accessibility and transcriptional control by modelling a dynamic equilibrium between DNA methylation and demethylation. Our research revealed 5hmC enrichment along genes and non-coding regulatory regions associated with specific developmental pathways in the genome of mouse incisor and molar dental pulp. Although the overall distribution of 5hmC is similar, the intensity and location of the 5hmC peaks significantly differs between the incisor and molar pulp genome, indicating cell type-specific epigenetic variations. Our study suggests that the differential DNA demethylation pattern could account for the distinct regulatory mechanisms underlying the tooth-specific ontogenetic programs.
Topics: Animals; Cell Differentiation; Dental Pulp; Genome; Incisor; Mice; Odontoblasts
PubMed: 34676418
DOI: 10.1093/jb/mvab114 -
Dental Pulp Stem Cell-Derived Extracellular Vesicles Mitigate Haematopoietic Damage after Radiation.Stem Cell Reviews and Reports Apr 2021Radiation therapy can cause haematopoietic damage, and mesenchymal stem cells (MSCs) derived extracellular vesicles (EVs) have been shown to reverse this damage. Our...
Radiation therapy can cause haematopoietic damage, and mesenchymal stem cells (MSCs) derived extracellular vesicles (EVs) have been shown to reverse this damage. Our previous research showed that dental pulp stem cells (DPSCs) have a strong proliferation capacity and can produce abundant amounts of EVs to meet the requirements for use in vitro and in vivo. DPSCs derived EVs (DPSCs-EVs) are evaluated for their effect on reducing haematopoietic damage. Haematopoietic stem cell (HSC) numbers and function were assessed by flow cytometry, peripheral blood cell counts, histology and bone marrow transplantation. Epidermal growth factor (EGF) was used as a reference for evaluating the efficiency of EVs. miRNA microarray was employed to find out the changes of miRNA expression after cells being irradiated in vivo and the role they may play in mitigation the radiation caused injury. We observed the effect of DPSCs-EVs on promoting proliferation and inhibiting apoptosis of human umbilical vein endothelial cells (HUVECs) and FDC-P1 cells in vitro. We found that DPSCs-EVs and EGF could comparably inhibit the decrease in WBC, CFU count and KSL cells in vivo. We also verified that EVs could accelerate the recovery of long-term HSCs. In summary, DPSCs-EVs showed an apoptosis resistant effect on HUVECs and FDC-P1 cells after radiation injury in vitro. EVs from DPSCs were comparable to EGF in their ability to regulate haematopoietic regeneration after radiation injury in vivo. Radiation could alter the expression of some miRNAs in bone marrow cells, and EVs could correct these changes to some extent. Graphical abstract.
Topics: Dental Pulp; Endothelial Cells; Epidermal Growth Factor; Extracellular Vesicles; Hematopoietic Stem Cell Transplantation; Humans; MicroRNAs; Radiation Injuries; Stem Cells
PubMed: 32749649
DOI: 10.1007/s12015-020-10020-x -
Scientific Reports Oct 2023Vascular calcification, an ectopic calcification exacerbated by aging and renal dysfunction, is closely associated with cardiovascular disease. However, early detection...
Vascular calcification, an ectopic calcification exacerbated by aging and renal dysfunction, is closely associated with cardiovascular disease. However, early detection indicators are limited. This study focused on dental pulp stones, ectopic calcifications found in oral tissues that are easily identifiable on dental radiographs. Our investigation explored the frequency and timing of these calcifications in different locations and their relationship to aortic calcification. In cadavers, we examined the association between the frequency of dental pulp stones and aortic calcification, revealing a significant association. Notably, dental pulp stones appeared prior to aortic calcification. Using a rat model of hyperphosphatemia, we confirmed that dental pulp stones formed earlier than calcification in the aortic arch. Interestingly, there were very few instances of aortic calcification without dental pulp stones. Additionally, we conducted cell culture experiments with vascular smooth muscle cells (SMCs) and dental pulp cells (DPCs) to explore the regulatory mechanism underlying high phosphate-mediated calcification. We found that DPCs produced calcification deposits more rapidly and exhibited a stronger augmentation of osteoblast differentiation markers compared with SMCs. In conclusion, the observation of dental pulp stones through X-ray examination during dental checkups could be a valuable method for early diagnosis of aortic calcification risk.
Topics: Rats; Animals; X-Rays; Dental Pulp Calcification; Radiography; Vascular Calcification; Early Diagnosis; Dental Pulp
PubMed: 37903847
DOI: 10.1038/s41598-023-45902-w -
The Chinese Journal of Dental Research Mar 2022Microspheres have been widely utilised as versatile carriers in biomedical applications. In recent years, as a new type of injectable scaffold, microspheres have...
Microspheres have been widely utilised as versatile carriers in biomedical applications. In recent years, as a new type of injectable scaffold, microspheres have attracted increasing attention in the field of regenerative medicine owing to their various advantages including their small size, large specific surface area and mimicry of the 3D native environment. These characteristics enable them to adopt the narrow and irregular anatomy of the tooth and become an ideal scaffold for endodontic regeneration. Microspheres play an important role in carrying biologics (cells, biomolecules and drugs), which effectively regulate the fate of stem cells and control the release of growth factors and drugs. Cell-laden microspheres, which can be divided into microcarriers and microcapsules, have great application prospects in dental pulp regeneration. This paper summarises the properties and characteristics of microsphere scaffolds used in tissue engineering, placing emphasis on their advantages and applications in endodontic regeneration.
Topics: Dental Pulp; Microspheres; Regeneration; Regenerative Medicine; Tissue Engineering
PubMed: 35293708
DOI: 10.3290/j.cjdr.b2752709 -
Dental Materials Journal Feb 2022This study aimed to investigate the effects of silicates on the proliferation and odontogenic differentiation of human dental pulp cells (hDPCs) in vitro. HDPCs were...
This study aimed to investigate the effects of silicates on the proliferation and odontogenic differentiation of human dental pulp cells (hDPCs) in vitro. HDPCs were cultured in the presence of calcium silicate (CS) extracts, while calcium hydroxide (CH) extracts and culture medium without CH or CS were used as the control groups. The calcium and phosphorus ion concentrations in the CS were similar to those in the control groups, but the concentration of silicon ions in the CS extracts was higher than that in the control groups. HDPCs cultured with CS and CH extracts at dilution of 1/128 proliferated significantly more than those cultured with the control treatments. CS extracts promoted cell migration, enhanced the expression of odontogenic marker genes and conspicuously increased odontogenesis-related protein production and the release of cytokines, suggesting that CS bioactive ceramics possess excellent biocompatibility and bioactivity and have the potential for application as pulp-capping agents.
Topics: Calcium Compounds; Cell Differentiation; Cell Proliferation; Cells, Cultured; Dental Pulp; Humans; Silicates
PubMed: 34408120
DOI: 10.4012/dmj.2021-042 -
European Endodontic Journal Aug 2021Since the 1960s, there has been contradictory evidence regarding the association between periodontal pathology and the status of the pulp. The purpose of this study was...
OBJECTIVE
Since the 1960s, there has been contradictory evidence regarding the association between periodontal pathology and the status of the pulp. The purpose of this study was to evaluate the histopathological changes of pulp tissue with severe periodontal disease, including vertical bone loss involving the major apical foramen, and compared them with the histological pulpal status of teeth with healthy periodontium.
METHODS
This case-controlled study included 35 intact teeth with severe periodontitis of hopeless prognosis (test group) and 35 teeth without periodontitis extracted for orthodontic reasons (control group). For each tooth, periodontal and endodontic parameters such as probing depth and pulpal vitality were recorded, and the pulp tissue was evaluated histologically. The data were analysed with a significance level of 0.05.
RESULTS
Vital pulp was observed in all specimens of both groups (P=1). Pulpal inflammation in the apical portion was observed in 81.71% of the severe periodontitis group, whereas all teeth in the control group demonstrated no signs of pulpal inflammation. Dystrophic calcification and pulp stones were observed in 7.5% of the periodontitis group and 5.7% of the healthy group (P>0.05). Pulp fibrosis was observed in 22.8% of the periodontitis group and 2.8% of the control group (P=0.012). Pulpal necrosis was not noted in either group. In the periodontitis group, internal resorption was present in 22.8% of cases (P=0.005) and external resorption was present in 80% of cases (P<0.001). In the control group, no internal or external resorption was observed in any of the specimens. No differences were noted in the study patients with regard to sex or age.
CONCLUSION
Periodontal disease does not significantly affect pulp vitality and pulpal calcifications. However internal and/or external resorption was significantly different between the two groups as well as apical inflammation and pulp fibrosis.
Topics: Dental Pulp; Dental Pulp Calcification; Dental Pulp Necrosis; Humans; Periodontitis; Tooth Apex
PubMed: 34650012
DOI: 10.14744/eej.2021.96268 -
The Journal of Clinical Pediatric... 2020The objective of this manuscript was to review the literature on dental trauma splints and discuss materials used for splinting injured teeth in terms of their... (Review)
Review
The objective of this manuscript was to review the literature on dental trauma splints and discuss materials used for splinting injured teeth in terms of their properties and conditions that are required for optimal stabilization. A literature search was conducted in the PubMed database with the keywords: "trauma splints", "dental trauma" and "traumatic dental injuries". The search was limited to English language publications. 42 publications fulfilled the inclusion criteria and were in accordance with the current recommendations. Optimal splinting of the teeth after trauma is one of the main predictors for pulpal and periodontal healing. The splints stabilize and protect the teeth, creating favorable conditions for the regeneration of the supporting tissues. Their application and removal should be easy and fast without any additional irritating of the surrounding tissues. The materials used to stabilize the injured teeth should keep the tooth in the original position, allowing for its physiological mobility.
Topics: Dental Pulp; Splints; Tooth Mobility
PubMed: 32271668
DOI: 10.17796/1053-4625-44.2.1 -
Journal of Dental Research Mar 2023Although vital pulp therapy should be performed by promoting the wound-healing capacity of dental pulp, existing pulp-capping materials were not developed with a focus...
Although vital pulp therapy should be performed by promoting the wound-healing capacity of dental pulp, existing pulp-capping materials were not developed with a focus on the pulpal repair process. In previous investigations of wound healing in dental pulp, we found that organic dentin matrix components (DMCs) were degraded by matrix metalloproteinase-20, and DMC degradation products containing protein S100A7 (S100A7) and protein S100A8 (S100A8) promoted the pulpal wound-healing process. However, the direct use of recombinant proteins as pulp-capping materials may cause clinical problems or lead to high medical costs. Thus, we hypothesized that functional peptides derived from recombinant proteins could solve the problems associated with direct use of such proteins. In this study, we identified functional peptides derived from the protein S100 family and investigated their effects on dental pulp tissue. We first performed amino acid sequence alignments of protein S100 family members from several mammalian sources, then identified candidate peptides. Next, we used a peptide array method that involved human dental pulp stem cells (hDPSCs) to evaluate the mineralization-inducing ability of each peptide. Our results supported the selection of 4 candidate functional peptides derived from proteins S100A8 and S100A9. Direct pulp-capping experiments in a rat model demonstrated that 1 S100A8-derived peptide induced greater tertiary dentin formation compared with the other peptides. To investigate the mechanism underlying this induction effect, we performed liquid chromatography-tandem mass spectrometry analysis using hDPSCs and the S100A8-derived peptide; the results suggested that this peptide promotes tertiary dentin formation by inhibiting inflammatory responses. In addition, this peptide was located in a hairpin region on the surface of S100A8 and could function by direct interaction with other molecules. In summary, this study demonstrated that a S100A8-derived functional peptide promoted wound healing in dental pulp; our findings provide insights for the development of next-generation biological vital pulp therapies.
Topics: Rats; Humans; Animals; Dental Pulp; Dentin, Secondary; Dental Pulp Capping; Peptides; Recombinant Proteins; Mammals
PubMed: 36415061
DOI: 10.1177/00220345221135766 -
Journal of Dental Research Apr 2021Odontoblast differentiation is a complex and multistep process regulated by signaling pathways, including the Wnt/β-catenin signaling pathway. Both positive and...
Odontoblast differentiation is a complex and multistep process regulated by signaling pathways, including the Wnt/β-catenin signaling pathway. Both positive and negative effects of Wnt/β-catenin signaling 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 Wnt/β-catenin in dentinogenesis, we used dental pulp cells from a panel of transgenic mice, in which fluorescent protein expression identifies cells at different stages of odontoblast and osteoblast differentiation. Our results showed that exposure of pulp cells to WNT3a at various times and durations did not induce premature differentiation of odontoblasts. These treatments supported the survival of undifferentiated cells in dental pulp and promoted the formation of 2.3GFP preodontoblasts and their rapid transition into differentiated odontoblasts expressing DMP1-Cherry and DSPP-Cerulean transgenes. WNT3a also promoted osteogenesis in dental pulp cultures. These findings provide critical information for the development of improved treatments for vital pulp therapy and dentin regeneration.
Topics: Animals; Cell Differentiation; Dental Pulp; Dentinogenesis; Mice; Odontoblasts; Wnt Signaling Pathway; beta Catenin
PubMed: 33103548
DOI: 10.1177/0022034520967353 -
Journal of the Formosan Medical... Jan 2022Dental pulp fibroblasts can protect dental pulp from microbial invasion. However, little is known about the interaction between pulp fibroblasts and the immune cells. In...
BACKGROUND/PURPOSE
Dental pulp fibroblasts can protect dental pulp from microbial invasion. However, little is known about the interaction between pulp fibroblasts and the immune cells. In this study, the production of proinflammatory cytokines related to inflammatory cell recruitment was evaluated in tumor necrosis factor (TNF)-α-stimulated human dental pulp fibroblasts (HDPFs). The role of TNF-α-stimulated HDPFs in the cell fusion under inflammatory process was determined with the cell co-culture with peripheral blood mononuclear cells (PBMCs).
METHODS
HDPFs were stimulated with various concentrations of TNF-α, and the secretion of interleukin (IL)-6, IL-8 and monocyte chemoattractant protein (MCP)-1 was analyzed by the enzyme-linked immunosorbent assay. The mRNA expression levels of intercellular adhesion molecule-1 (ICAM-1), macrophage colony-stimulating factor (M-CSF), receptor activator of nuclear factor κB ligand (RANKL) and osteoprotegerin (OPG) were determined by real-time quantitative polymerase chain reaction. TNF-α-treated HDPFs were co-cultured with PBMCs for 21 days, and characteristics of cell differentiation were assessed.
RESULTS
TNF-α induced IL-6, IL-8 and MCP-1 production in HDPFs. Moreover, mRNA expression levels of ICAM-1, M-CSF and OPG were significantly increased in TNF-α-treated HDPFs. Co-culture of TNF-α-treated HDPFs and PBMCs stimulated formation of tartrate-resistant acid phosphatase (TRAP)-positive multinucleated cells, and the F-actin rings were observed in these multinucleated cells.
CONCLUSION
Our results indicate that under the stimulation of TNF-α, HDPFs may amplify inflammatory response by cytokines production, which in turn can modulate the differentiation of immune cells.
Topics: Dental Pulp; Fibroblasts; Humans; Inflammation; Leukocytes, Mononuclear
PubMed: 34049758
DOI: 10.1016/j.jfma.2021.05.007