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Archives of Oral Biology Apr 2024Notum is a secreted deacylase, which is crucial for tooth dentin development in mice. This study aimed to investigate the effect of NOTUM on the odontoblastic...
NOTUM plays a bidirectionally modulatory role in the odontoblastic differentiation of human stem cells from the apical papilla through the WNT/β-catenin signaling pathway.
OBJECTIVE
Notum is a secreted deacylase, which is crucial for tooth dentin development in mice. This study aimed to investigate the effect of NOTUM on the odontoblastic differentiation of human stem cells from the apical papilla (hSCAPs), to reveal the potential value of NOTUM in pulp-dentin complex regeneration.
DESIGN
The expression pattern of NOTUM in human tooth germs and during in vitro odontoblastic differentiation of hSCAPs was evaluated by immunohistochemical staining, and quantitative polymerase chain reaction, respectively. To manipulate the extracellular NOTUM level, ABC99 or small interfering RNA was used to down-regulate it, while recombinant NOTUM protein was added to up-regulate it. The effects of changing NOTUM level on the odontoblastic differentiation of hSCAPs and its interaction with the WNT/β-catenin signaling pathway were studied using alkaline phosphatase staining, alizarin red staining, quantitative polymerase chain reaction, and western blot.
RESULTS
NOTUM was observed in the apical papilla of human tooth germs. During in vitro odontoblastic differentiation of hSCAPs, NOTUM expression initially increased, while the WNT/β-catenin pathway was activated. Downregulation of NOTUM hindered odontoblastic differentiation. Recombinant NOTUM protein had varying effects on odontoblastic differentiation depending on exposure duration. Continuous addition of the protein inhibited both odontoblastic differentiation and the WNT/β-catenin pathway. However, applying the protein solely in the first 3 days enhanced odontoblastic differentiation and up-regulated the WNT/β-catenin pathway.
CONCLUSION
NOTUM demonstrated a bidirectional impact on in vitro odontoblastic differentiation of hSCAPs, potentially mediated by the WNT/β-catenin pathway. These findings suggest its promising potential for pulp-dentin complex regeneration.
Topics: Humans; beta Catenin; Cell Differentiation; Cells, Cultured; Dental Pulp; Down-Regulation; Odontoblasts; Stem Cells; Wnt Signaling Pathway
PubMed: 38278124
DOI: 10.1016/j.archoralbio.2024.105896 -
Frontiers in Physiology 2023Mouse and human genetic studies indicate key roles of the ligand in odontogenesis. Previous studies have identified effectors and regulators of the Wnt signaling...
Mouse and human genetic studies indicate key roles of the ligand in odontogenesis. Previous studies have identified effectors and regulators of the Wnt signaling pathway actively expressed during key stages of tooth morphogenesis. However, limitations in multiplexing and spatial resolution hindered a more comprehensive analysis of these signaling molecules. Here, profiling of transcriptomes using fluorescent multiplex hybridization and single-cell RNA-sequencing (scRNA-seq) provide robust insight into the synchronized expression patterns of , , and simultaneously during tooth development. First, we identified transcripts restricted to the epithelium at the stage of tooth bud morphogenesis, contrasting that of and localization to the dental mesenchyme. By embryonic day 15.5 (E15.5), a marked shift of expression from dental epithelium to mesenchyme was noted, while and expression remained enriched in the mesenchyme. By postnatal day 0 (P0), co-localization patterns of , , and were observed in both terminally differentiating and secreting odontoblasts of molars and incisors. Interestingly, exhibited robust expression in fully differentiated ameloblasts at the developing cusp tip of both molars and incisors, an observation not previously noted in prior studies. At P7 and 14, after the mineralization of dentin and enamel, expression was limited to odontoblasts. Meanwhile, Wnt modulators showed reduced or absent signals in molars. In contrast, strong signals persisted in ameloblasts (for ) and odontoblasts (for , , and ) towards the proximal end of incisors, near the cervical loop. Our scRNA-seq analysis used CellChat to further contextualize Wnt pathway-mediated communication between cells by examining ligand-receptor interactions among different clusters. The co-localization pattern of , , and in both terminally differentiating and secreting odontoblasts of molars and incisors potentially signifies the crucial ligand-modulator interaction along the gradient of cytodifferentiation starting from each cusp tip towards the apical region. These data provide cell type-specific insight into the role of Wnt ligands and mediators during epithelial-mesenchymal interactions in odontogenesis.
PubMed: 38274045
DOI: 10.3389/fphys.2023.1316635 -
Frontiers in Physiology 2023Upon endoplasmic reticulum (ER) stress, inositol-requiring enzyme 1 (IRE1) is activated, which subsequently converts an unspliced X-box binding protein 1 () mRNA to a...
Upon endoplasmic reticulum (ER) stress, inositol-requiring enzyme 1 (IRE1) is activated, which subsequently converts an unspliced X-box binding protein 1 () mRNA to a spliced mRNA that encodes a potent XBP1S transcription factor. XBP1S is essential for relieving ER stress and secretory cell differentiation. We previously established ; mice that constitutively expressed XBP1S in the -expressing cells as well as in the cells derived from the -expressing cells. In this study, we analyzed the dental phenotype of ; mice. We first generated a mutant minigene that corresponds to the recombinant allele (the allele that has undergone Cre-mediated recombination) and confirmed that the minigene expressed XBP1S that does not require IRE1α activation . Consistently, immunohistochemistry showed that XBP1S was constitutively expressed in the odontoblasts and other dental pulp cells in ; mice. Plain X-ray radiography and µCT analysis revealed that constitutive expression of XBP1S altered the dental pulp chamber roof- and floor-dentin formation, resulting in a significant reduction in dentin/cementum formation in ; mice, compared to age-matched control mice. However, there is no significant difference in the density of dentin/cementum between these two groups of mice. Histologically, persistent expression of XBP1S caused a morphological change in odontoblasts in ; mice. Nevertheless, hybridization and immunohistochemistry analyses showed that continuous expression of XBP1S had no apparent effects on the expression of the and genes. In conclusion, these results support that sustained production of XBP1S adversely affected odontoblast function and dentin formation.
PubMed: 38274041
DOI: 10.3389/fphys.2023.1319954 -
Experimental and Therapeutic Medicine Feb 2024Cluster of differentiation (CD)44 is a marker of dental pulp stem cells and is involved in odontoblast differentiation and calcification. Chemokine-like receptor 1...
Cluster of differentiation (CD)44 is a marker of dental pulp stem cells and is involved in odontoblast differentiation and calcification. Chemokine-like receptor 1 (CMKLR1), also known as chemerin receptor 23 (ChemR23) is also expressed in odontoblasts and dental pulp stem cells and is involved in inflammation suppression and tooth regeneration. Resolvin E1, a bioactive lipid, is a CMKLR1 ligand that mediates the chemerin-CMKLR1 interaction and suppresses pulpal inflammation. The present study clarified the intracellular and tissue localization of CD44 and CMKLR1 by immunohistochemical staining of normal pulp and pulp with pulpitis from 12-week-old male Wistar rat teeth or human teeth. In addition, the localization of CD44 and CMKLR1 in human dental pulp stem cells was observed by immunofluorescence staining. The present study also examined the involvement of resolvin E1 in inhibiting inflammation and calcification by western blotting. CD44- and CMKLR1-positive cells were confirmed in the odontoblast layer in normal dental pulp of rats and humans. CD44 was mainly localized in the cell membrane and CMKLR1 was mainly found in the cytoplasm of human dental pulp stem cells. CMKLR1 was also confirmed in the odontoblast layer in rats and humans with pulpitis but CD44 was not present. Following treatment of dental pulp stem cells with lipoteichoic acid, which imitates Gram-positive bacterial infection, resolvin E1 did not suppress the expression of cyclooxygenase-2 or of the odontoblast differentiation marker, dentin sialophosphoprotein. Furthermore, resolvin E1 induced the differentiation of dental pulp stem cells into odontoblasts even in the presence of the inflammatory stimulus.
PubMed: 38264427
DOI: 10.3892/etm.2023.12363 -
International Journal of Molecular... Jan 2024MMP13 gene expression increases up to 2000-fold in mineralizing dental pulp cells (DPCs), with research previously demonstrating that global MMP13 deletion resulted in...
MMP13 gene expression increases up to 2000-fold in mineralizing dental pulp cells (DPCs), with research previously demonstrating that global MMP13 deletion resulted in critical alterations in the dentine phenotype, affecting dentine-tubule regularity, the odontoblast palisade, and significantly reducing the dentine volume. Global MMP13-KO and wild-type mice of a range of ages had their molar teeth injured to stimulate reactionary tertiary dentinogenesis. The response was measured qualitatively and quantitatively using histology, immunohistochemistry, micro-CT, and qRT-PCR in order to assess changes in the nature and volume of dentine deposited as well as mechanistic links. MMP13 loss affected the reactionary tertiary dentine quality and volume after cuspal injury and reduced Nestin expression in a non-exposure injury model, as well as mechanistic links between MMP13 and the Wnt-responsive gene Axin2. Acute pulpal injury and pulp exposure to oral fluids in mice teeth showed upregulation of the MMP13 in vivo, with an increase in the gene expression of , , and evident. These results indicate that MMP13 is involved in tertiary reactionary dentine formation after tooth injury in vivo, potentially acting as a key molecule in the dental pulp during dentine-pulp repair processes.
Topics: Animals; Mice; Dentinogenesis; Matrix Metalloproteinase 13; Molar; Odontoblasts; Tooth Injuries
PubMed: 38255947
DOI: 10.3390/ijms25020875 -
Scientific Reports Jan 2024Plant extracts have been useful for oral health or dentistry. However, only a few evidence-based justifications exist. This study evaluated Multidentia crassa (Hiern)... (Review)
Review
Plant extracts have been useful for oral health or dentistry. However, only a few evidence-based justifications exist. This study evaluated Multidentia crassa (Hiern) Bridson & Verdc, one of the oral health-used plants in Malawi. Gas chromatography-mass spectrometry (GC-MS) and Fourier transform infrared (FT-IR) identified the extracts' compounds. The pharmacokinetics of the identified compounds were studied using pkCSM and SwissADME, and molecular docking studies were used to identify potential drug candidates for oral health by predicting the binding affinity of the compounds to cyclooxygenases, interleukin-1 beta receptors, odontoblast cold sensor proteins, and purinergic receptor P2X3. FT-IR analysis showed characteristic peaks of phenols, carboxylic acids, alkenes, alkyl halides, amines, esters, ethers, aromatics, and lipids. GC-MS results showed the presence of 58 bioactive phytocompounds, some of which have various pharmacological activities relevant to oral health. Molecular docking further validated stigmastan-3,5-diene's potency for analgesic and anti-inflammatory purposes. Based on a literature review, this is the first report on the bioactive compounds of M. crassa extracts showing analgesic and anti-inflammatory effects. This study's results can lead to new herbal and conventional medicines. Therefore, we recommend in vivo and in vitro studies to elucidate the pharmacological effects of the plant extracts.
Topics: Molecular Docking Simulation; Gas Chromatography-Mass Spectrometry; Spectroscopy, Fourier Transform Infrared; Analgesics; Anti-Inflammatory Agents; Rubiaceae; Plant Extracts; Dentistry
PubMed: 38253619
DOI: 10.1038/s41598-023-47737-x -
BMC Oral Health Jan 2024To assess histologically the success of the pulp capping approach performed in traumatically exposed dogs' teeth using a novel injectable gelatin-treated dentin matrix...
BACKGROUND
To assess histologically the success of the pulp capping approach performed in traumatically exposed dogs' teeth using a novel injectable gelatin-treated dentin matrix light cured hydrogel (LCG-TDM) compared with LCG, MTA and TheraCal LC.
METHODS
Sixty-four dogs' teeth were divided into two groups (each including 32 teeth) based on the post-treatment evaluation period: group I: 2 weeks and group II: 8 weeks. Each group was further subdivided according to the pulp capping material into four subgroups (n = 8), with subgroup A (light-cured gelatin hydrogel) as the control subgroup, subgroup B (LCG-TDM), subgroup C (TheraCal LC), and subgroup D (MTA). Pulps were mechanically exposed in the middle of the cavity floor and capped with different materials. An assessment of periapical response was performed preoperatively and at 8 weeks. After 2 and 8-week intervals, the dogs were sacrificed, and the teeth were stained with hematoxylin-eosin and graded by using a histologic scoring system. Statistical analysis was performed using the chi-square and Kruskal-Wallis tests (p = 0.05).
RESULTS
All subgroups showed mild inflammation with normal pulp tissue at 2 weeks with no significant differences between subgroups (p ≤ 0.05), except for the TheraCal LC subgroup, which exhibited moderate inflammation (62.5%). Absence of a complete calcified bridge was reported in all subgroups at 2 weeks, while at 8 weeks, the majority of samples in the LCG-TDM and MTA-Angelus subgroups showed complete dentin bridge formation and absence of inflammatory pulp response with no significant differences between them (p ≤ 0.05). However, the formed dentin in the LCG-TDM group was significantly thicker, with layers of ordered odontoblasts identified to create a homogeneous tubular structure and numerous dentinal tubule lines suggesting a favourable trend towards dentin regeneration. TheraCal LC samples revealed a reasonably thick dentin bridge with moderate inflammation (50%) and LCG showed heavily fibrous tissue infiltrates with areas of degenerated pulp with no signs of hard tissue formation.
CONCLUSIONS
LCG-TDM, as an extracellular matrix-based material, has the potential to regenerate dentin and preserve pulp vitality, making it a viable natural alternative to silicate-based cements for healing in vivo dentin defects in direct pulp-capping procedures.
Topics: Animals; Dogs; Calcium Compounds; Dental Pulp; Dental Pulp Capping; Dentin; Dentin, Secondary; Drug Combinations; Gelatin; Hydrogels; Inflammation; Oxides; Pulp Capping and Pulpectomy Agents; Silicates
PubMed: 38243218
DOI: 10.1186/s12903-024-03868-9 -
Journal of Translational Medicine Jan 2024Revascularization and restoration of normal pulp-dentin complex are important for tissue-engineered pulp regeneration. Recently, a unique periodontal tip-like...
BACKGROUND
Revascularization and restoration of normal pulp-dentin complex are important for tissue-engineered pulp regeneration. Recently, a unique periodontal tip-like endothelial cells subtype (POTCs) specialized to dentinogenesis was identified. We have confirmed that TPPU, a soluble epoxide hydrolase (sEH) inhibitor targeting epoxyeicosatrienoic acids (EETs) metabolism, promotes bone growth and regeneration by angiogenesis and osteogenesis coupling. We hypothesized that TPPU could also promote revascularization and induce POTCs to contribute to pulp-dentin complex regeneration. Here, we in vitro and in vivo characterized the potential effect of TPPU on the coupling of angiogenesis and odontogenesis and investigated the relevant mechanism, providing new ideas for pulp-dentin regeneration by targeting sEH.
METHODS
In vitro effects of TPPU on the proliferation, migration, and angiogenesis of dental pulp stem cells (DPSCs), human umbilical vein endothelial cells (HUVECs) and cocultured DPSCs and HUVECs were detected using cell counting kit 8 (CCK8) assay, wound healing, transwell, tube formation and RT-qPCR. In vivo, Matrigel plug assay was performed to outline the roles of TPPU in revascularization and survival of grafts. Then we characterized the VEGFR2 + POTCs around odontoblast layer in the molar of pups from C57BL/6 female mice gavaged with TPPU. Finally, the root segments with DPSCs mixed with Matrigel were implanted subcutaneously in BALB/c nude mice treated with TPPU and the root grafts were isolated for histological staining.
RESULTS
In vitro, TPPU significantly promoted the migration and tube formation capability of cocultured DPSCs and HUVECs. ALP and ARS staining and RT-qPCR showed that TPPU promoted the osteogenic and odontogenic differentiation of cultured cells, treatment with an anti-TGF-β blocking antibody abrogated this effect. Knockdown of HIF-1α in HUVECs significantly reversed the effect of TPPU on the expression of angiogenesis, osteogenesis and odontogenesis-related genes in cocultured cells. Matrigel plug assay showed that TPPU increased VEGF/VEGFR2-expressed cells in transplanted grafts. TPPU contributed to angiogenic-odontogenic coupling featured by increased VEGFR2 + POTCs and odontoblast maturation during early dentinogenesis in molar of newborn pups from C57BL/6 female mice gavaged with TPPU. TPPU induced more dental pulp-like tissue with more vessels and collagen fibers in transplanted root segment.
CONCLUSIONS
TPPU promotes revascularization of dental pulp regeneration by enhancing migration and angiogenesis of HUVECs, and improves odontogenic differentiation of DPSCs by TGF-β. TPPU boosts the angiogenic-odontogenic coupling by enhancing VEGFR2 + POTCs meditated odontoblast maturation partly via upregulating HIF-1α, which contributes to increasing pulp-dentin complex for tissue-engineered pulp regeneration.
Topics: Mice; Animals; Female; Humans; Dental Pulp; Epoxide Hydrolases; Mice, Nude; Stem Cells; Mice, Inbred C57BL; Regeneration; Cells, Cultured; Human Umbilical Vein Endothelial Cells; Cell Differentiation; Dentin
PubMed: 38229161
DOI: 10.1186/s12967-024-04863-y -
Archives of Razi Institute Aug 2023Amoxicillin is one of the most commonly prescribed antibiotics in children. As a result, it is prescribed as the first line of defence against cutaneous,...
Amoxicillin is one of the most commonly prescribed antibiotics in children. As a result, it is prescribed as the first line of defence against cutaneous, gastrointestinal, and respiratory infections. The objective of this study was to evaluate the effects of Amoxicillin on the formation of dentin and enamel during the secretory and early phases of mineralization. Regarding the materials and methods used to perform this study, 16 pregnant adult Wistar rats were equally divided into two groups. The first group did not receive the drug and was prescribed a saline solution (control group), and the other group received 250 mg/kg/day of Amoxicillin (experimental group). From the 13 gestational day until delivery, the treatment was given every day by oral gavage. After birth, the newborns also received the same treatment as their mothers from the first day until 7 or 12 days after birth. The newborns were sacrificed at 7 and 12 days postnatally, the jaws were dissected, the maxilla was taken, the samples were fixed in 10% formaldehyde solution, and the upper first molars were analyzed histologically by H & E stain and histomorphometrically by image J to examine the enamel, dentin, ameloblast and odontoblast mean thickness in both groups and each healing periods. The study's results showed that the mean enamel, as well as ameloblastic and odontoblastic layer thickness, were significantly different in the Amoxicillin 250 mg/kg group, compared to the control group. The result also revealed a non-significant group difference in the dentin thickness in both durations (P-value at day 7=0.147 and the P-value at day 12=0.054). Vacuolization of the ameloblastic and odontoblastic layers was observed in the Amoxicillin-treated group in both durations.
Topics: Infant, Newborn; Humans; Pregnancy; Female; Child; Rats; Animals; Amoxicillin; Rats, Wistar; Anti-Bacterial Agents; Wound Healing
PubMed: 38226389
DOI: 10.32592/ARI.2023.78.4.1333 -
European Endodontic Journal Aug 2023Hyaluronic acid (HA) is glycosaminoglycan and one of important factors in extracellular matrix. In an inflamed pulp, when niche biology is conducive, the recruitment of...
OBJECTIVE
Hyaluronic acid (HA) is glycosaminoglycan and one of important factors in extracellular matrix. In an inflamed pulp, when niche biology is conducive, the recruitment of human dental pulp stem cells (hDPSCs) will take place and differentiate into odontoblast like cell, creating reparative dentine and expressing dentine sialophosphoprotein (DSPP). Therefore, the purpose of this study was to analyze the potential of hydrogel HA in various concentration towards hDPSCs differentiation via DSPP expression at day 7 and 14.
METHODS
After hDPSCs incubation reaching 80% confluence, cells were then starved for 24 hours. Then, culture media were supplemented with osteogenic media. hDPSCs planted into 96 well plate and HA 10 μg/mL, 20 μg/mL, and 30 μg/mL were added. DSPP expression was analysed using elisa reader at day 7 and 14, qualitative result was analysed using alizarin red at day 21. Data was analysed using one-way ANOVA.
RESULTS
At day 7, there was a statistically significant different potential of HA conditioned media in various concentration (p<0.05) towards hDPSCs differentiation via expression of DSPP with HA 30 μg/mL being the most potential concentration to increase DSPP expression.
CONCLUSION
HA have the potential to increase odontoblast differentiation process via expression of DSPP, with HA 30 μg/mL being the optimum concentration for hDPSCs. (EEJ-2022-12-169).
Topics: Humans; Dental Pulp; Hyaluronic Acid; Hydrogels; Dentin; Stem Cells
PubMed: 38219035
DOI: 10.14744/eej.2023.59672