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Cell Cycle (Georgetown, Tex.) Nov 2011Residing within human dental pulp are cells of an ectomesenchymal origin which have the potential to differentiate into odontoblast-like cells. These cells have a...
INTRODUCTION
Residing within human dental pulp are cells of an ectomesenchymal origin which have the potential to differentiate into odontoblast-like cells. These cells have a limited growth potential owing to the effects of cell senescence. This study examines the effects of immortalizing odontoblast-like cells on cell proliferation and mineralization by comparing transformed dental pulp stem cells (tDPSCs) and non-transformed dental pulp stem cells (nDPSCs).
RESULTS
With the exogenous expression of hTERT, tDPSCs maintained a continued expression of odontogenic markers for cell proliferation and mineralization (ALP, COL-1, DMP-1, DSPP, OCN amd OPN)as did nDPScs. Oncoprotein expression was seen in both groups except for a noted absence of p16 in the tDPSCs. nDPSCs also showed lower levels of total ALP and DNA activity in comparison to tDPSCs when assayed as well as low telomerase activity readings.
METHODS
Using a retroviral vector, exogenous human telomerase reverse transcriptase (hTERT) was expressed in tDPSCs. Both cell groups were cultured and their telomerase activities is determined using a telomerase quantification assay. Also examined were the expression of genes involved in proliferation and mineralization such as human alkaline phosphatase (ALP), β-actin, collagen 1 (col-1), core binding factor (cbfa-1), dentin matrix protein (DMP-1), dentin sialophosphoprotein (DSPP), GAPDH, hTERT, osteocalcin (OCN), osteopontin (OPN) as well as oncoproteins involved in senescence (p16, p21 and p53) using RT-PCR. DNA and alkaline phosphatase activity was assayed in both cell groups.
CONCLUSIONS
These results indicate maintainance of odontoblast-like differentiation characteristics after retroviral transformation with hTERT and suggest a possible link with a reduced p16 expression.
Topics: Biomarkers; Cell Differentiation; Cell Proliferation; Colorimetry; Cyclin-Dependent Kinase Inhibitor p16; Cytoskeleton; Dental Pulp; Humans; Pluripotent Stem Cells; Reverse Transcriptase Polymerase Chain Reaction; Telomerase; Transduction, Genetic; Tumor Suppressor Protein p53; beta-Galactosidase
PubMed: 22067611
DOI: 10.4161/cc.10.22.18093 -
Human Cell Apr 2018CD146 and STRO-1 are endothelial biomarkers that are co-expressed on the cellular membranes of blood vessels within human dental pulp tissue. This study characterized...
CD146 and STRO-1 are endothelial biomarkers that are co-expressed on the cellular membranes of blood vessels within human dental pulp tissue. This study characterized the percentage of dentin-like structures produced by CD146-positive (CD146) human dental pulp stem cells (DPSCs), compared with their CD146-negative (CD146) counterparts. DPSC populations were enriched using magnetic-activated cell sorting (MACS), yielding CD146 and CD146 cells, as well as mixtures composed of 25% CD146 cells and 75% CD146 cells (CD146). Cell growth assays indicated that CD146 cells exhibit an approximate 3-4 h difference in doubling time, compared with CD146 cells. Cell cycle distributions were determined by flow cytometry analysis. The low percentage of CD146 cells' DNA content in G/G phase were compared with CD146 and non-separated cells. In contrast to CD146 and non-separated cells, prompt mineralization was observed in CD146 cells. Subsequently, qRT-PCR revealed high mRNA expression of CD146 and Alkaline phosphatase in mineralization-induced CD146 cells. CD146 cells were also observed high adipogenic ability by Oil red O staining. Histological examinations revealed an increased area of dentin/pulp-like structures in transplanted CD146 cells, compared with CD146 and CD146 cells. Immunohistochemical studies detected dentin matrix protein-1 (DMP1) and dentin sialophosphoprotein (DSPP), as well as human mitochondria, in transplanted DPSCs. Co-expression of CD146 and GFP indicated that CD146 was expressed in transplanted CD146 cells. CD146 cells may promote mineralization and generate dentin/pulp-like structures, suggesting a role in self-renewal of stem cells and dental pulp regenerative therapy.
Topics: Adipogenesis; CD146 Antigen; Cell Cycle; Cell Differentiation; Cell Proliferation; Cells, Cultured; Dental Pulp; Dentin; Humans; Regeneration; Regenerative Medicine; Stem Cells
PubMed: 29313241
DOI: 10.1007/s13577-017-0198-2 -
Stem Cell Research & Therapy Jul 2018The concept of establishing a dental stem cell (DSC) bank for oral and maxillofacial regeneration has become of great interest but it remains at a primitive stage....
BACKGROUND
The concept of establishing a dental stem cell (DSC) bank for oral and maxillofacial regeneration has become of great interest but it remains at a primitive stage. The routine application of serum-containing conditions for human DSC (hDSC) culture is in great controversy considering that the animal-originated serum can cause serious ethical concerns and lead to increasingly irrelevant variables, errors, and poor repeatability of experiment results. Thus, this study aimed to establish a safe, stable and efficient hDSC serum-free culturing system for future DSC bank usage.
METHODS
Dental pulp stem cells (DPSCs) from human permanent tooth pulp were isolated, expanded, passaged, and divided into two groups according to their culture conditions: group 1 was the serum-containing medium (SCM) group; and group 2 was the serum-free Essential 8 medium (E8) group. DPSCs were characterized first, followed by cell proliferation, pluripotency, and migration study in SCM and E8 medium.
RESULTS
Human DPSCs (hDPSCs) in E8 medium demonstrated greater proliferation, pluripotency, migration ability and less apoptosis. hDPSCs could be successfully induced to the adipogenic, osteogenic, neurogenic, and chondrogenic lineages in E8 group. Real-time polymerase chain reaction indicated that the expression of PPAR-γ, RUNX2, OCN and MAP-2 was higher in E8 group. CONCLUSIONS: Compared with serum-containing medium, E8 medium exhitibed higher ability in maintaining the cell proliferation, pluripotency, migration, and stability. This new serum-free culture environment might be applicable for hDSC culture in the future.
Topics: Cell Culture Techniques; Dental Pulp; Humans; Stem Cells
PubMed: 29996915
DOI: 10.1186/s13287-018-0928-8 -
Human Cell Jul 2020Mesenchymal stem cells are a highly promising source of cells for regeneration therapy because of their multilineage differentiation potential. However, distinct markers...
Mesenchymal stem cells are a highly promising source of cells for regeneration therapy because of their multilineage differentiation potential. However, distinct markers for mesenchymal stem cells are not well-established. To identify new candidate marker genes for multipotent human dental pulp stem cells, we analyzed the characteristics and gene expression profiles of cell clones obtained from a single dental pulp specimen derived from an 11-year-old female patient. Fifty colony-forming single cell-derived clones were separately cultured until the cessation of growth. These clones varied in their proliferation abilities and surface marker (STRO-1 and CD146) expression patterns, as well as their odontogenic, adipogenic, and chondrogenic differentiation potentials. Four clones maintained their original differentiation potentials during long-term culture. Gene expression profile by DNA microarray analysis of five representative clones identified 1227 genes that were related to multipotency. Ninety of these 1227 genes overlapped with genes reportedly involved in 'stemness or differentiation'. Based on the predicted locations of expressed protein products and large changes in expression levels, 14 of the 90 genes were selected as candidate dental pulp stem cell markers, particularly in relation to their multipotency characteristics. This characterization of cell clones obtained from a single specimen of human dental pulp provided information regarding new candidate marker genes for multipotent dental pulp stem cells, which could facilitate efficient analysis or enrichment of multipotent stem cells.
Topics: Cell Differentiation; Cell Proliferation; Cells, Cultured; Child; Clone Cells; Dental Pulp; Female; Gene Expression; Humans; Multipotent Stem Cells
PubMed: 32180208
DOI: 10.1007/s13577-020-00327-9 -
Molecular Pain 2017Persistent pain can occur after routine dental treatments in which the dental pulp is injured. To better understand pain chronicity after pulp injury, we assessed...
Persistent pain can occur after routine dental treatments in which the dental pulp is injured. To better understand pain chronicity after pulp injury, we assessed whether dental pulp injury in mice causes changes to the sensory nervous system associated with pathological pain. In some experiments, we compared findings after dental pulp injury to a model of orofacial neuropathic pain, in which the mental nerve is injured. After unilateral dental pulp injury, we observed increased expression of activating transcription factor 3 (ATF3) and neuropeptide Y (NPY) mRNA and decreased tachykinin precursor 1 gene expression, in the ipsilateral trigeminal ganglion. We also observed an ipsilateral increase in the number of trigeminal neurons expressing immunoreactivity for ATF3, a decrease in substance P (SP) immunoreactive cells, and no change in the number of cells labeled with IB4. Mice with dental pulp injury transiently exhibit hindpaw mechanical allodynia, out to 12 days, while mice with mental nerve injury have persistent hindpaw allodynia. Mice with dental pulp injury increased spontaneous consumption of a sucrose solution for 17 days while mental nerve injury mice did not. Finally, after dental pulp injury, an increase in expression of the glial markers Iba1 and glial fibrillary acidic protein occurs in the transition zone between nucleus caudalis and interpolaris, ipsilateral to the injury. Collectively these studies suggest that dental pulp injury is associated with significant neuroplasticity that could contribute to persistent pain after of dental pulp injury.
Topics: Activating Transcription Factor 3; Animals; Dental Pulp; Female; Hyperalgesia; Mandibular Nerve; Mice, Inbred BALB C; Mice, Inbred C57BL; Neuralgia; Neuroglia; Neuronal Plasticity; Neurons; Neuropeptide Y; Trigeminal Ganglion
PubMed: 28580829
DOI: 10.1177/1744806917715173 -
International Journal of Molecular... Sep 2020High-intensity laser therapy (HILT) and photobiomodulation therapy (PBMT) are two types of laser treatment. According to recent clinical reports, PBMT promotes wound... (Review)
Review
Wound Healing and Cell Dynamics Including Mesenchymal and Dental Pulp Stem Cells Induced by Photobiomodulation Therapy: An Example of Socket-Preserving Effects after Tooth Extraction in Rats and a Literature Review.
High-intensity laser therapy (HILT) and photobiomodulation therapy (PBMT) are two types of laser treatment. According to recent clinical reports, PBMT promotes wound healing after trauma or surgery. In addition, basic research has revealed that cell differentiation, proliferation, and activity and subsequent tissue activation and wound healing can be promoted. However, many points remain unclear regarding the mechanisms for wound healing induced by PBMT. Therefore, in this review, we present an example from our study of HILT and PBMT irradiation of tooth extraction wounds using two types of lasers with different characteristics (diode laser and carbon dioxide laser). Then, the effects of PBMT on the wound healing of bone tissues are reviewed from histological, biochemical, and cytological perspectives on the basis of our own study of the extraction socket as well as studies by other researchers. Furthermore, we consider the feasibility of treatment in which PBMT irradiation is applied to stem cells including dental pulp stem cells, the theme of this Special Issue, and we discuss research that has been reported on its effect.
Topics: Animals; Bone and Bones; Cell Differentiation; Dental Pulp; Laser Therapy; Lasers, Gas; Lasers, Semiconductor; Male; Periodontal Ligament; Rats; Rats, Wistar; Stem Cells; Tooth Extraction; Wound Healing
PubMed: 32961958
DOI: 10.3390/ijms21186850 -
International Journal of Molecular... Apr 2024Dental tissue stem cells (DTSCs) are well known for their multipotent capacity and regenerative potential. They also play an important role in the immune response of... (Review)
Review
Dental tissue stem cells (DTSCs) are well known for their multipotent capacity and regenerative potential. They also play an important role in the immune response of inflammatory processes derived from caries lesions, periodontitis, and gingivitis. These oral diseases are triggered by toxins known as lipopolysaccharides (LPS) produced by gram-negative bacteria. LPS present molecular patterns associated with pathogens and are recognized by Toll-like receptors (TLRs) in dental stem cells. In this review, we describe the effect of LPS on the biological behavior of DTSCs. We also focus on the molecular sensors, signaling pathways, and emerging players participating in the interaction of DTSCs with lipopolysaccharides. Although the scientific advances generated provide an understanding of the immunomodulatory potential of DTSCs, there are still new reflections to explore with regard to their clinical application in the treatment of oral inflammatory diseases.
Topics: Animals; Humans; Dental Pulp; Lipopolysaccharides; Signal Transduction; Stem Cells; Toll-Like Receptors; Bacterial Infections
PubMed: 38673923
DOI: 10.3390/ijms25084338 -
TheScientificWorldJournal 2015
Topics: Dental Pulp; Dentistry; Humans; Light; Mouth; Tissue Engineering
PubMed: 25884026
DOI: 10.1155/2015/308138 -
Scientific Reports Feb 2021Bone-resorbing osteoclasts are regulated by the relative ratio of the differentiation factor, receptor activator NF-kappa B ligand (RANKL) and its decoy receptor,...
Bone-resorbing osteoclasts are regulated by the relative ratio of the differentiation factor, receptor activator NF-kappa B ligand (RANKL) and its decoy receptor, osteoprotegerin (OPG). Dental tissue-localized-resorbing cells called odontoclasts have regulatory factors considered as identical to those of osteoclasts; however, it is still unclear whether the RANKL/OPG ratio is a key factor for odontoclast regulation in dental pulp. Here, we showed that odontoclast regulators, macrophage colony-stimulating factor-1, RANKL, and OPG were detectable in mouse pulp of molars, but OPG was dominantly expressed. High OPG expression was expected to have a negative regulatory effect on odontoclastogenesis; however, odontoclasts were not detected in the dental pulp of OPG-deficient (KO) mice. In contrast, damage induced odontoclast-like cells were seen in wild-type pulp tissues, with their number significantly increased in OPG-KO mice. Relative ratio of RANKL/OPG in the damaged pulp was significantly higher than in undamaged control pulp. Pulp damages enhanced hypoxia inducible factor-1α and -2α, reported to increase RANKL or decrease OPG. These results reveal that the relative ratio of RANKL/OPG is significant to pulpal odontoclastogenesis, and that OPG expression is not required for maintenance of pulp homeostasis, but protects pulp from odontoclastogenesis caused by damages.
Topics: Animals; Biomarkers; Cell Differentiation; Cellular Microenvironment; Dental Pulp; Fluorescent Antibody Technique; Gene Expression; Immunohistochemistry; Mice; Models, Biological; Odontogenesis; Osteoclasts; Osteoprotegerin; RANK Ligand
PubMed: 33633362
DOI: 10.1038/s41598-021-84354-y -
Scientific Reports Jul 2019Direct visualization of the spatial relationships of the dental pulp tissue at the whole-organ has remained challenging. CLARITY (Clear Lipid-exchanged Acrylamide Tissue...
Direct visualization of the spatial relationships of the dental pulp tissue at the whole-organ has remained challenging. CLARITY (Clear Lipid-exchanged Acrylamide Tissue hYdrogel) is a tissue clearing method that has enabled successful 3-dimensional (3D) imaging of intact tissues with high-resolution and preserved anatomic structures. We used CLARITY to study the whole human dental pulp with emphasis on the neurovascular components. Dental pulps from sound teeth were CLARITY-cleared, immunostained for PGP9.5 and CD31, as markers for peripheral neurons and blood vessels, respectively, and imaged with light sheet microscopy. Visualization of the whole dental pulp innervation and vasculature was achieved. Innervation comprised 40% of the dental pulp volume and the vasculature another 40%. Marked innervation morphological differences between uni- and multiradicular teeth were found, also distinct neurovascular interplays. Quantification of the neural and vascular structures distribution, diameter and area showed that blood vessels in the capillary size range was twice as high as that of nerve fibers. In conclusion whole CLARITY-cleared dental pulp samples revealed 3D-morphological neurovascular interactions that could not be visualized with standard microscopy. This represents an outstanding tool to study the molecular and structural intricacies of whole dental tissues in the context of disease and treatment methods.
Topics: Acrylamide; Adult; Bicuspid; Capillaries; Cuspid; Dental Pulp; Fluorescent Antibody Technique; Healthy Volunteers; Humans; Hydrogels; Imaging, Three-Dimensional; Microscopy; Nerve Fibers; Nerve Net; Young Adult
PubMed: 31350423
DOI: 10.1038/s41598-019-47221-5