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Journal of Dental Research Jul 2014The precise regulation of odontoblast differentiation and osteoclastogenic cytokine expression in human dental pulp cells (HDPCs) is crucial for the pathology of...
The precise regulation of odontoblast differentiation and osteoclastogenic cytokine expression in human dental pulp cells (HDPCs) is crucial for the pathology of bacteria-related pulpitis. Although the up-regulation of nucleotide-binding oligomerization domain-containing protein 2 (NOD2) has been reported in inflamed human dental pulps, the role of NOD2 in the differentiation of HDPCs remains unclear. Here, we show the involvement of NOD2 in odontoblast differentiation together with osteoclastogenic cytokine expression in HDPCs. Treatment with muramyl dipeptide (MDP), a known NOD2-agonist, significantly inhibited odontoblast differentiation of HDPCs, as revealed by reduced ALP activity, osteoblast/odontoblast marker expression, and mineralized nodule formation. Importantly, the forced down-regulation of NOD2 by small interfering RNA (siRNA) recovered MDP-down-regulated odontoblast differentiation. MDP-elicited suppression of odontoblast differentiation resulted from the increased expression of MKP-1 protein and the subsequent decline of MAPKs phosphorylation, which is a prerequisite for odontoblast differentiation. Furthermore, we found that MDP treatment elevated the expression of osteoclastogenic cytokines in HDPCs, which was also reversed by NOD2 silencing. Analysis of these data, taken together, suggests that the regulation of NOD2 expression upon MDP challenge might serve as an intrinsic mechanism that underlies the hindered dentin formation and accelerated dentin resorption in bacterial infection-mediated pulpitis.
Topics: Acetylmuramyl-Alanyl-Isoglutamine; Adjuvants, Immunologic; Cell Differentiation; Cell Line; Cytokines; Dental Pulp; Dual Specificity Phosphatase 1; Gene Silencing; Humans; Macrophage Colony-Stimulating Factor; Mitogen-Activated Protein Kinases; Nod2 Signaling Adaptor Protein; Odontoblasts; Osteoclasts; Osteoprotegerin; RANK Ligand; RNA, Small Interfering
PubMed: 24820666
DOI: 10.1177/0022034514535214 -
Cellular Physiology and Biochemistry :... 2017As a vital degradation and recycling system, autophagy plays an essential role in regulating the differentiation of stem cells. We previously showed that iron chelator...
BACKGROUND/AIMS
As a vital degradation and recycling system, autophagy plays an essential role in regulating the differentiation of stem cells. We previously showed that iron chelator deferoxamine (DFO) could promote the repair ability of dental pulp stem cells (DPSCs). Here, we investigated the effect of DFO in autophagy and the role of autophagy in regulating the migration and odontoblast differentiation of DPSCs.
METHODS
Transmission electron microscopy, immunofluorescence staining and western blotting were performed to evaluate the autophagic activity of DPSCs. Transmigration assay, alkaline phosphatase staining/activity, alizarin red S staining and quantitative PCR were performed to examine the migration and odontoblast differentiation of DPSCs. Reactive oxygen species (ROS) levels and the effects of ROS scavenger in autophagy induction were also detected. Autophagy inhibitors (3-MA and bafilomycin A1) and lentiviral vectors carrying ATG5 shRNA sequences were used for autophagy inhibition.
RESULTS
Early exposure to DFO promoted the mineralization of DPSCs and increased autophagic activity. Autophagy inhibition suppressed DFO-induced DPSC migration and odontoblast differentiation. Furthermore, DFO treatment could induce autophagy partly through hypoxia-inducible factor 1α/B cell lymphoma 2/adenovirus E1B 19K-interacting protein 3 (HIF-1α/BNIP3) pathway in a ROS-dependent manner.
CONCLUSION
DFO increased DPSC migration and differentiation, which might be modulated through ROS-induced autophagy.
Topics: Adenine; Adolescent; Autophagy; Autophagy-Related Protein 5; Beclin-1; Cell Differentiation; Cell Movement; Cell Proliferation; Cells, Cultured; Deferoxamine; Dental Pulp; Humans; Hypoxia-Inducible Factor 1, alpha Subunit; Macrolides; Membrane Proteins; Microscopy, Electron, Transmission; Microtubule-Associated Proteins; Odontoblasts; Proto-Oncogene Proteins; RNA Interference; RNA, Small Interfering; Reactive Oxygen Species; Stem Cells; Young Adult
PubMed: 29131087
DOI: 10.1159/000484506 -
Genesis (New York, N.Y. : 2000) Oct 2019To gain a better understanding of the progression of progenitor cells in the odontoblast lineage, we have examined and characterized the expression of a series of GFP...
To gain a better understanding of the progression of progenitor cells in the odontoblast lineage, we have examined and characterized the expression of a series of GFP reporters during odontoblast differentiation. However, previously reported GFP reporters (pOBCol2.3-GFP, pOBCol3.6-GFP, and DMP1-GFP), similar to the endogenous proteins, are also expressed by bone-forming cells, which made it difficult to delineate the two cell types in various in vivo and in vitro studies. To overcome these difficulties we generated DSPP-Cerulean/DMP1-Cherry transgenic mice using a bacterial recombination strategy with the mouse BAC clone RP24-258g7. We have analyzed the temporal and spatial expression of both transgenes in tooth and bone in vivo and in vitro. This transgenic animal enabled us to visualize the interactions between odontoblasts and surrounding tissues including dental pulp, ameloblasts and cementoblasts. Our studies showed that DMP1-Cherry, similar to Dmp1, was expressed in functional and fully differentiated odontoblasts as well as osteoblasts, osteocytes and cementoblasts. Expression of DSPP-Cerulean transgene was limited to functional and fully differentiated odontoblasts and correlated with the expression of Dspp. This transgenic animal can help in the identification and isolation of odontoblasts at later stages of differentiation and help in better understanding of developmental disorders in dentin and odontoblasts.
Topics: Animals; Cell Differentiation; Extracellular Matrix Proteins; Fluorescent Dyes; Genes, Reporter; Green Fluorescent Proteins; Mice; Mice, Transgenic; Odontoblasts; Phosphoproteins; Sialoglycoproteins; Transgenes
PubMed: 31271259
DOI: 10.1002/dvg.23324 -
Journal of Endodontics Apr 2014Emerging understanding about interactions between stem cells, scaffolds, and morphogenic factors has accelerated translational research in the field of dental pulp... (Review)
Review
Emerging understanding about interactions between stem cells, scaffolds, and morphogenic factors has accelerated translational research in the field of dental pulp tissue engineering. Dental pulp stem cells constitute a subpopulation of cells endowed with self-renewal and multipotency. Dental pulp stem cells seeded in biodegradable scaffolds and exposed to dentin-derived morphogenic factors give rise to a pulplike tissue capable of generating new dentin. Notably, dentin-derived proteins are sufficient to induce dental pulp stem cell differentiation into odontoblasts. Ongoing work is focused on developing ways of mobilizing dentin-derived proteins and disinfecting the root canal of necrotic teeth without compromising the morphogenic potential of these signaling molecules. On the other hand, dentin by itself does not appear to be capable of inducing endothelial differentiation of dental pulp stem cells despite the well-known presence of angiogenic factors in dentin. This is particularly relevant in the context of dental pulp tissue engineering in full root canals in which access to blood supply is limited to the apical foramina. To address this challenge, scientists are looking at ways to use the scaffold as a controlled-release device for angiogenic factors. The aim of this article was to present and discuss current strategies to functionalize injectable scaffolds and customize them for dental pulp tissue engineering. The long-term goal of this work is to develop stem cell-based therapies that enable the engineering of functional dental pulps capable of generating new tubular dentin in humans.
Topics: Angiogenic Proteins; Cell Differentiation; Dental Pulp; Dentin; Humans; Multipotent Stem Cells; Odontoblasts; Proteins; Signal Transduction; Stem Cells; Tissue Engineering; Tissue Scaffolds
PubMed: 24698691
DOI: 10.1016/j.joen.2014.01.013 -
Journal of Dental Research Mar 2013Root development and tooth eruption are very important topics in dentistry. However, they remain among the less-studied and -understood subjects. Root development...
Root development and tooth eruption are very important topics in dentistry. However, they remain among the less-studied and -understood subjects. Root development accompanies rapid tooth eruption, but roots are required for the movement of teeth into the oral cavity. It has been shown that the dental follicle and bone remodeling are essential for tooth eruption. So far, only limited genes have been associated with root formation and tooth eruption. This may be due to the difficulties in studying late stages of tooth development and tooth movement and the lack of good model systems. Transgenic mice with eruption problems and short or no roots can be used as a powerful model for further deciphering of the cellular, molecular, and genetic mechanisms underlying root formation and tooth eruption. Better understanding of these processes can provide hints on delivering more efficient dental therapies in the future.
Topics: Animals; Odontoblasts; Tooth Eruption; Tooth Root; beta Catenin
PubMed: 23345536
DOI: 10.1177/0022034512474469 -
The International Journal of... Feb 1995The basic features on the vitamin D endocrine system, synthesis of the main metabolite 1,25-dihydroxyvitamin D3 (1,25) and its genomic action mediated via the vitamin D... (Review)
Review
The basic features on the vitamin D endocrine system, synthesis of the main metabolite 1,25-dihydroxyvitamin D3 (1,25) and its genomic action mediated via the vitamin D receptor (VDR), are reviewed. Calbindin-D9k, calbindin-D28k and osteocalcin are presented as the most-extensively investigated vitamin D-dependent calcium-binding proteins. The action of 1,25 on the basic process of proliferation and differentiation is introduced. Then, the basis of the systemic theory of vitamin D action on teeth (clinical and experimental data and the dissimilar distribution of VDR and of potential vitamin D-dependent proteins in dental cells) are exposed. Finally, the data obtained with calbindin-D9k, calbindin-D28k, osteocalcin and VDR, which supports the theory that ameloblasts and odontoblasts are target-cells for 1,25 is presented. As a perspective, a cross-survey of the 1,25 and tooth-related literature is proposed which may indicate potential target-genes for 1,25 in teeth as done previously for calbindins-D.
Topics: Ameloblasts; Animals; Calbindin 1; Calbindins; Calcitriol; Humans; Odontoblasts; Osteocalcin; Receptors, Calcitriol; S100 Calcium Binding Protein G; Tooth
PubMed: 7626415
DOI: No ID Found -
Aging Cell Mar 2024Once tooth development is complete, odontoblasts and their progenitor cells in the dental pulp play a major role in protecting tooth vitality from external stresses....
Once tooth development is complete, odontoblasts and their progenitor cells in the dental pulp play a major role in protecting tooth vitality from external stresses. Hence, understanding the homeostasis of the mature pulp populations is just as crucial as understanding that of the young, developing ones for managing age-related dentinal damage. Here, it is shown that loss of Cpne7 accelerates cellular senescence in odontoblasts due to oxidative stress and DNA damage accumulation. Thus, in Cpne7-null dental pulp, odontoblast survival is impaired, and aberrant dentin is extensively formed. Intraperitoneal or topical application of CPNE7-derived functional peptide, however, alleviates the DNA damage accumulation and rescues the pathologic dentin phenotype. Notably, a healthy dentin-pulp complex lined with metabolically active odontoblasts is observed in 23-month-old Cpne7-overexpressing transgenic mice. Furthermore, physiologic dentin was regenerated in artificial dentinal defects of Cpne7-overexpressing transgenic mice. Taken together, Cpne7 is indispensable for the maintenance and homeostasis of odontoblasts, while promoting odontoblastic differentiation of the progenitor cells. This research thereby introduces its potential in oral disease-targeted applications, especially age-related dental diseases involving dentinal loss.
Topics: Mice; Animals; Aging, Premature; Dental Pulp; Cellular Senescence; Odontoblasts; Cell Differentiation; Mice, Transgenic
PubMed: 38105557
DOI: 10.1111/acel.14061 -
Journal of Cellular Biochemistry Oct 2010Apoptosis has been described extensively in tooth development, which is under tight control of multiple apoptosis regulators, including anti-apoptotic protein Bcl-2....
Apoptosis has been described extensively in tooth development, which is under tight control of multiple apoptosis regulators, including anti-apoptotic protein Bcl-2. However, it is totally unclear how Bcl-2 is related to odontogenesis, especially dentinogenesis. Using a transgenic mouse Col2.3Bcl-2 in which human Bcl-2 was overexpressed in odontoblasts, the effect of Bcl-2 on dentinogenesis was investigated. Overexpression of Bcl-2 was detected by immunohistochemistry and Western blot. Odontoblast apoptosis was evaluated by TUNEL and Western blot detection of cleaved caspase-3. Odontoblast differentiation was assessed by real-time PCR detection of dentin matrix expression. Dentin mineralization was evaluated by micro-CT in vivo, and alizarin red S staining and calcium content analysis in vitro. Bcl-2 was found to be overexpressed in odontoblasts and prevent their apoptosis. Odontoblast differentiation and mineralization was inhibited by Bcl-2, as evidenced by lower expressions of DMP-1, OC, and DSPP, and decreased odontoblast mineralization in vitro, as well as decreased dentin thickness and mineral density in vivo when compared to the wild-type animals. Inhibition of odontoblast differentiation by Bcl-2 occurs, at least partially, via a suppression of MEK-ERK1/2 signaling pathway. In conclusion, Bcl-2 overexpression prevents odontoblast apoptosis and impairs dentin formation, partially via an inhibition of odontoblast differentiation. This study revealed some novel functions of Bcl-2 in dentinogenesis in addition to its anti-apoptotic effect, which shed some light on the genetic complexity of tooth development.
Topics: Animals; Apoptosis; Calcification, Physiologic; Cell Differentiation; Dentinogenesis; Drug Delivery Systems; Genes, bcl-2; Humans; Mice; Mice, Transgenic; Odontoblasts; Proto-Oncogene Proteins c-bcl-2
PubMed: 20518070
DOI: 10.1002/jcb.22722 -
The International Journal of... 2024Tooth formation is a process tightly regulated by reciprocal interactions between epithelial and mesenchymal tissues. These epithelial-mesenchyme interactions regulate...
Tooth formation is a process tightly regulated by reciprocal interactions between epithelial and mesenchymal tissues. These epithelial-mesenchyme interactions regulate the expression of target genes via transcription factors. Among the regulatory elements governing this process, Epiprofin/Sp6 is a zinc finger transcription factor which is expressed in the embryonic dental epithelium and in differentiating pre-odontoblasts. knockout (-/-) mice present severe dental abnormalities, such as supernumerary teeth and enamel hypoplasia. Here, we describe dentin defects in molars and incisors of -/- mice. We observed that in the absence of Epfn, markers of early odontoblast differentiation, such as alkaline phosphatase activity, expression, and Collagen Type I deposition, are downregulated. In addition, the expression of tight and gap junction proteins was severely impaired in the predontoblastic cell layer of developing -/- molars. Altogether, our data shows that Epfn is crucial for the proper differentiation of dental mesenchymal cells towards functional odontoblasts and subsequent dentin-matrix deposition.
Topics: Mice; Animals; Odontoblasts; Dentin Dysplasia; Cell Differentiation; Odontogenesis; Transcription Factors
PubMed: 38591690
DOI: 10.1387/ijdb.240029lj -
Acta Bio-medica : Atenei Parmensis Dec 2023Congenital heart disease (CHD) is an abnormality in the structure or function of the cardio-circulatory system present at birth and the ventricular septal defect (VSD)...
Congenital heart disease (CHD) is an abnormality in the structure or function of the cardio-circulatory system present at birth and the ventricular septal defect (VSD) is the most common CHD in children. This study aimed to determine any differences in the histological structure of primary teeth between both healthy children and those children with ventricular septal defects in Erbil City. Methods enrolled children were divided into two groups. Group I (control) & group II (CHD) aged between 6-10 years old. A total of 44 children were collected, (22 children) in each group. Enamel, dentin, and odontoblast layers were examined histologically. Unpaired t-test used for statistical analysis. Results: The histopathological sections showed a significant difference in enamel, dentin, and odontoblast layer thickness (255.8 ± 41.68- 406.4 ±46.39), (1156 ± 116.0 - 1320 ± 117.4) and (29.74 ± 7.66 -41.38 ± 12.06) respectively, with p values (P < 0.0001) for enamel and dentin layer, and P < 0.0004 for odontoblast layer. A study of the images in the CHD group showed that the tooth tissue lost its integrity and cohesion in some places, and the thickness of the enamel and dentin layer in this group was significantly reduced compared to group I. Tissue loss in enamel, pulp, and dentin cell were observed. Also, connective tissue layers in the pulp were disrupted. Conclusions: CHD can alter the natural structure formation of primary teeth. Histologically, enamel, dentin, and odontoblasts layer thickness reduction are found in primary teeth in children with ventricular septal defects.
Topics: Infant, Newborn; Humans; Child; Dentin; Odontoblasts; Heart Defects, Congenital; Tooth, Deciduous; Heart Septal Defects, Ventricular
PubMed: 38054687
DOI: 10.23750/abm.v94i6.14567