The Experts below are selected from a list of 837 Experts worldwide ranked by ideXlab platform
William T Butler - One of the best experts on this subject based on the ideXlab platform.
-
Dentin sialophosphoprotein in biomineralization
Connective Tissue Research, 2010Co-Authors: Monica Prasad, William T Butler, Chunlin QinAbstract:Two of the proteins found in significant quantity in the extracellular matrix (ECM) of Dentin are Dentin phosphoprotein (DPP) and Dentin Sialoprotein (DSP). DPP, the most abundant of the noncollagenous proteins (NCPs) in Dentin is an unusually polyanionic protein, containing a large number of aspartic acids (Asp) and phosphoserines (Pse) in the repeating sequences of (Asp–Pse)n. and (Asp–Pse–Pse)n. The many negatively charged regions of DPP are thought to promote mineralization by binding calcium and presenting it to collagen fibers at the mineralization front during the formation of Dentin. This purported role of DPP is supported by a sizeable pool of in vitro mineralization data showing that DPP is an important initiator and modulator for the formation and growth of hydroxyapatite (HA) crystals. Quite differently, DSP is a glycoprotein, with little or no phosphate. DPP and DSP are the cleavage products of Dentin sialophosphoprotein (DSPP). Human and mouse genetic studies have demonstrated that mutations...
-
immunolocalization of osteopontin osteocalcin and Dentin Sialoprotein during dental root formation and early cementogenesis in the rat
Journal of Bone and Mineral Research, 2009Co-Authors: A L J J Bronckers, Mary C Farachcarson, Erwin Van Waveren, William T ButlerAbstract:: Using immunohistochemical methods we studied the tissue localization of the extracellular matrix proteins osteopontin (OPN), osteocalcin (OC), and Dentin Sialoprotein (DSP) during the formation of acellular and cellular cementum in newly born rats. In the layer of acellular cementum of developing incisor and molar teeth we found a very strong staining for OPN but not for DSP or OC. Many cells immediately adjacent to acellular cementum and PDL cells were also positive for OPN but not for DSP or for OC. In contrast, cellular cementum in molar teeth stained strongly for OPN and OC but not for DSP. Consistent with these observations, the cells engaged in the formation of cellular cementum (cementoblasts and cementocytes) reacted strongly for OPN and OC but not for DSP. In advanced stages of Dentinogenesis, both crown and root odontoblasts and Dentin stained for OPN, OC, and DSP. Cells and matrices of surrounding alveolar bone stained for OPN and OC but not for DSP. We conclude that cementoblasts and cementocytes of cellular cementum produce OPN and OC but not DSP and thus express an osteoblast-like, not an odontoblast-like, phenotype. The cells responsible for the production of acellular cementum are likely cells of the PDL in close contact with the dental root surface. These fibroblast-like cells express OPN but not OC or DSP and accordingly express only a partial osteoblastic phenotype.
-
colocalization of Dentin matrix protein 1 and Dentin Sialoprotein at late stages of rat molar development
Matrix Biology, 2004Co-Authors: Otto Baba, Chunlin Qin, Jan C. Brunn, James N. Wygant, Bradley W. Mcintyre, William T ButlerAbstract:Dentin matrix protein 1 (DMP1) and Dentin sialophosphoprotein (DSPP) are acidic proteins found in the extracellular matrices of bones and teeth. Recent data from gene knockouts, along with those of gene mutations, indicate that these two phosphoproteins are critical for bone and tooth development and/or maintenance. However, the precise functions of the two proteins have not been elucidated. In order to gain insights into their functions in tooth formation, we performed systematic, comparative investigations on the immunolocalization of DMP1 and Dentin Sialoprotein (DSP, a cleaved fragment of DSPP), using the rat first molar at different developmental stages as a model. Immunohistochemistry (IHC) was performed with specific, monoclonal antibodies against the COOH-terminal fragments of DMP1 and against DSP. In 1-day- and 1-week-old rats, weak immunoreactions for DMP1 were observed in Dentinal tubules while stronger reactions for DSP were seen in the tubules and preDentin. In rats older than 2 weeks, immunoreactions for DMP1 were found in Dentinal tubules, preDentin and odontoblasts. In 5-week- and 8-week-old rats, strong immunoreactions for DMP1 were widely distributed in odontoblasts and preDentin. The distribution pattern of DSP was strikingly similar to that of DMP1 after 2 weeks and the localization of each was distinctly different from that of bone Sialoprotein (BSP). The unique colocalization of DMP1 and DSPP in tooth development suggests that the two proteins play complementary and/or synergistic roles in formation and maintenance of healthy teeth.
-
Dentin Sialoprotein and phosphoprotein induce neutrophil recruitment a mechanism dependent on il 1β tnf α and cxc chemokines
Calcified Tissue International, 2004Co-Authors: Tarcilia Aparecida Silva, William T Butler, Vanessa Soares Lara, Joao Santana Da Silva, Gustavo Pompermaier Garlet, Fernando Q CunhaAbstract:Dentin is a reservoir of several potentially active molecules, and Dentin Sialoprotein (DSP) and Dentin phosphoprotein (DPP) are the two major non-collagenous proteins. It has been established that Dentin molecules are released as a consequence of osteoclast action during the resorption process. Along with osteoclasts, inflammatory cells seem to play an important role at sites of root resorption. Although the role of Dentin molecules in Dentinogenesis is well known, their role in pathological processes associated with Dentin matrix dissolution is unclear. Recent studies have suggested that Dentin components may function as chemotactic and activator signals for inflammatory cells at these sites. Herein we present evidence that demineralized Dentin crude extract, DSP, and DPP induced doseand time-dependent neutrophil migration into the peritoneal cavity of mice and that this activity was inhibited by dexamethasone, but not by indomethacin or MK886. The blockade of tumor necrosis factor-alpha (TNF-alpha) and interleukin-1 (IL-1) receptors inhibited neutrophil accumulation. The neutrophil migration was also diminished in the absence of the chemokines cytokine-induced neutrophil chemoattractant (KC) and macrophage inflammatory protein-2 (MIP-2), but not in the absence of macrophage inflammatory protein-1alpha (MIP-1alpha). These results demonstrate that Dentin induces neutrophil migration via the synthesis of IL-1beta, TNF-alpha, and chemokines and they suggest that Dentin matrix proteins may have an active role in inflammatory cell recruitment during pathological processes associated with Dentin and bone matrix dissolution.
-
Detection of Dentin Sialoprotein in rat periodontium
European Journal of Oral Sciences, 2004Co-Authors: Otto Baba, Chunlin Qin, Jan C. Brunn, Jarrod E. Jones, James N. Wygant, Bradley W. Mcintyre, William T ButlerAbstract:Cloning and sequencing of the cDNA indicates that Dentin sialophosphoprotein (DSPP) is a precursor of both Dentin Sialoprotein (DSP) and Dentin phosphoprotein (DPP). Dentin sialophosphoprotein must be proteolytically processed to form these two extracellular matrix (ECM) proteins. Numerous studies led us to conclude that DSP (and DSPP) are exclusively expressed by odontoblasts and preameloblasts. However, recent observations suggest a wider distribution. To test this hypothesis, we conducted systematic studies on rat first molar during root formation with immunohistochemical techniques using specific anti-DSP polyclonal and monoclonal antibodies. We also performed in situ hybridization, using high-stringency RNA probes to detect DSP transcripts. Immunohistochemical studies demonstrated that DSP is not only localized in odontoblasts, Dentin ECM and preameloblasts, but also in alveolar bone, cellular cementum, osteocytes, cementocytes, and their matrices. The results of in situ hybridization were consistent with those from immunohistochemistry, showing the expression of DSP transcripts in osteoblasts of alveolar bone, fibroblasts in periodontal ligament and cementoblasts in cellular cementum. Together, these observations suggest that DSP is involved in formation of the periodontium as well as tooth structures.
Helena H Ritchie - One of the best experts on this subject based on the ideXlab platform.
-
the functional significance of Dentin Sialoprotein phosphophoryn and Dentin Sialoprotein
International Journal of Oral Science, 2018Co-Authors: Helena H RitchieAbstract:Phosphophoryn (PP) and Dentin Sialoprotein (DSP) are the most dominant non-collagenous proteins in Dentin. PP is an extremely acidic protein that can function as a mineral nucleator for Dentin mineralization. DSP was first identified in 1981, yet its functional significance is still controversial. Historically, these two proteins were considered to be independently synthesized and secreted by dental pulp cells into the developing Dentin matrix. However, with the identification of the DSP coding sequence in 1994, followed 2 years later by the finding that the PP coding sequence was located immediately downstream from the DSP sequence, it became immediately clear that DSP and PP proteins were derived from a single DSP-PP (i.e., Dentin sialophosphoprotein, DSPP) transcript. Since DSPP cDNA became available, tremendous progress has been made in studying DSP-PP mRNA distribution and DSP generation from the DSP-PP precursor protein at specific cleavage sites by protease tolloid-related-1 (TLR1) or bone morphogenetic protein 1 (BMP1). The functions of DSP-PP and DSP were investigated via DSP-PP knockout (KO) and DSP knockin in DSP-PP KO mice. In addition, a number of in vitro studies aimed to elucidate DSPP and DSP function in dental pulp cells.
-
Phosphophoryn and Dentin Sialoprotein Effects on Dental Pulp Cell Migration, Proliferation, and Differentiation
MDPI AG, 2018Co-Authors: Shu-feng Chuang, Yu-hsuan Chen, Helena H RitchieAbstract:Phosphophoryn (PP) and Dentin Sialoprotein (DSP) are two of the most abundant Dentin matrix non-collagenous proteins, and are derived from Dentin Sialoprotein-phosphophoryn (DSP-PP) mRNA. Mutations in the DSP-PP gene are linked to Dentinogenesis imperfecta II and III. Previously, we reported transient DSP-PP expression in preameloblast cells first, followed by co-expression in preameloblasts and young odontoblasts, and finally sustained expression in odontoblasts. This phenomenon raised the possibility that DSP/PP proteins secreted by preameloblasts might promote dental pulp cell migration toward the dental pulp border and promote dental pulp cell differentiation. To examine the effects of DSP/PP proteins on dental pulp cell development, we investigated:(1) native PP effects on dental pulpcell migration and matrix protein expression; and (2) recombinant DSP/PP protein effects on cell proliferation and differentiation. We found that PP promoted cell migration and the expression of high levels of Col type I and PP in dental pulp cells. The addition of recombinant DSP/PP proteins affected cell proliferation and differentiation in a dental pulp cell line. These findings strongly suggest that DSP/PP may modulate cell migration, cell proliferation and differentiation, thus leading to Dentin formation. DSP/PP protein may be useful clinically for pulp tissue regeneration
-
the efficiency of Dentin Sialoprotein phosphophoryn processing is affected by mutations both flanking and distant from the cleavage site
Journal of Biological Chemistry, 2013Co-Authors: Robert T Yang, Glendale Lim, Zhihong Dong, Arthur M Lee, Colin T Yee, Robert S Fuller, Helena H RitchieAbstract:Normal Dentin mineralization requires two highly acidic proteins, Dentin Sialoprotein (DSP) and phosphophoryn (PP). DSP and PP are synthesized as part of a single secreted precursor, DSP-PP, which is conserved in marsupial and placental mammals. Using a baculovirus expression system, we previously found that DSP-PP is accurately cleaved into DSP and PP after secretion into medium by an endogenous, secreted, zinc-dependent Sf9 cell activity. Here we report that mutation of conserved residues near and distant from the G(447)↓D(448) cleavage site in DSP-PP(240) had dramatic effects on cleavage efficiency by the endogenous Sf9 cell processing enzyme. We found that: 1) mutation of residues flanking the cleavage site from P(4) to P(4)' blocked, impaired, or enhanced DSP-PP(240) cleavage; 2) certain conserved amino acids distant from the cleavage site were important for precursor cleavage; 3) modification of the C terminus by appending a C-terminal tag altered the pattern of processing; and 4) mutations in DSP-PP(240) had similar effects on cleavage by recombinant human BMP1, a candidate physiological processing enzyme, as was seen with the endogenous Sf9 cell activity. An analysis of a partial TLR1 cDNA from Sf9 cells indicates that residues that line the substrate-binding cleft of Sf9 TLR1 and human BMP1 are nearly perfectly conserved, offering an explanation of why Sf9 cells so accurately process mammalian DSP-PP. The fact that several mutations in DSP-PP(240) significantly modified the amount of PP(240) product generated from DSP-PP(240) precursor protein cleavage suggests that such mutation may affect the mineralization process.
-
expression of mineralized tissue associated proteins Dentin Sialoprotein and phosphophoryn in rodent hair follicles
Journal of Dermatological Science, 2011Co-Authors: Xu Na Tang, Cassou Lozada Y Marcelo, Helena H RitchieAbstract:Abstract Background Mammalian hair development and tooth development are controlled by a series of reciprocal epithelial–mesenchymal interactions. Similar growth factors and transcription factors, such as fibroblast growth factor (FGF), sonic hedgehog homolog (SHH), bone morphogenetic proteins (BMPs) and Wnt10a, were reported to be involved in both of these interactions. Dentin Sialoprotein (DSP) and phosphophoryn (PP) are the two major non-collagenous proteins secreted by odontoblasts that participate in Dentin mineralization during tooth development. Because of striking similarities between tooth development and hair follicle development, we investigated whether DSP and/or PP proteins may also play a role in hair follicle development. Objective In this study, we examined the presence and location of DSP/PP proteins during hair follicle development. Methods Rat PP proteins were detected using immunohistochemical/immunofluorescent staining. DSP–PP mRNAs were detected by in situ hybridization with riboprobes. LacZ expression was detected in mouse tissues using a DSP–PP promoter-driven LUC in transgenic mice. Results We found that PP proteins and DSP–PP mRNAs are present in rat hair follicles. We also demonstrate that an 8 kb DSP–PP promoter is able to drive lacZ expression in hair follicles. Conclusion We have firmly established the presence of DSP/PP in mouse and rat hair follicles by immunohistochemical/immunofluorescent staining, in situ hybridization with riboprobes and transgenic mice studies. The expression of DSP/PP in hair follicles is the first demonstration that major mineralization proteins likely may also contribute to soft tissue development. This finding opens a new avenue for future investigations into the molecular-genetic management of soft tissue development.
-
dynamic processing of recombinant Dentin Sialoprotein phosphophoryn protein
Journal of Biological Chemistry, 2007Co-Authors: Valentina Godovikova, Helena H RitchieAbstract:Dentin Sialoprotein (DSP) and phosphophoryn (PP) are the two noncollagenous proteins classically linked to Dentin but more recently found in bone, kidney, and salivary glands. These two proteins are derived from a single copy DSP-PP gene. Although this suggests that the DSP-PP gene is first transcribed into DSP-PP mRNAs, which later undergo processing to yield the DSP and PP proteins, this mechanism has not yet been demonstrated because of the inability to identify a DSP-PP precursor protein from any cell or tissue sample. To study this problem, we utilized a baculovirus expression system to produce recombinant DSP-PP precursor proteins from a DSP-PP240 cDNA, which represents one of several endogenous DSP-PP transcripts that influence various tooth mineralization phases. Our in vitro results demonstrate that DSP-PP240 precursor proteins are produced by this system and are capable of self-processing to yield both DSP and PP proteins. We further demonstrated that purified recombinant DSP-PP240, purified recombinant PP240, and the native highly phosphorylated protein (equivalent to the PP523 isoform) have proteolytic activity. These newly identified tissue proteases may play key roles in tissue modeling during organogenesis.
Mary Macdougall - One of the best experts on this subject based on the ideXlab platform.
-
Dentin Sialoprotein facilitates dental mesenchymal cell differentiation and Dentin formation
Scientific Reports, 2017Co-Authors: Lei Chen, Mary Macdougall, Junsheng Feng, Kevin J. Donly, Zhuo Chen, Feng Wang, Lisa Shoff, Shuo ChenAbstract:Dentin Sialoprotein (DSP) is a Dentin extracellular matrix protein. It is involved in dental mesenchymal cell lineages and Dentin formation through regulation of its target gene expression. DSP mutations cause Dentin genetic diseases. However, mechanisms of DSP in controlling dental mesenchymal cell differentiation are unknown. Using DSP as bait, we screened a protein library from mouse odontoblastic cells and found that DSP is a ligand and binds to cell surface receptor, occludin. Further study identified that the C-terminal DSP domainaa 363–458 interacts with the occludin extracellular loop 2aa 194–241. The C-terminal DSP domain induced phosphorylation of occludin Ser490 and focal adhesion kinase (FAK) Ser722 and Tyr576. Coexpression of DSP, occludin and FAK was detected in dental mesenchymal cells during tooth development. Occludin physically interacts with FAK, and occludin and FAK phosphorylation can be blocked by DSP and occludin antibodies. This DSP domain facilitates dental mesenchymal cell differentiation and mineralization. Furthermore, transplantation and pulp-capping procedures revealed that this DSP domain induces endogenous dental pulp mesenchymal cell proliferation, differentiation and migration, while stimulating blood vessel proliferation. This study elucidates the mechanism of DSP in dental mesenchymal lineages and implies that DSP may serve as a therapeutic agent for Dentin-pulp complex regeneration in dental caries.
-
Dentin Sialoprotein is a Novel Substrate of Matrix Metalloproteinase 9 in vitro and in vivo.
Scientific reports, 2017Co-Authors: Guohua Yuan, Lei Chen, Junsheng Feng, Guobin Yang, Chunyan Wan, Merry L. Lindsey, Kevin J. Donly, Mary MacdougallAbstract:Dentin Sialoprotein (DSP) is essential for Dentinogenesis and processed into fragments in the odontoblast-like cells and the tooth compartments. Matrix metalloproteinase 9 (MMP9) is expressed in teeth from early embryonic to adult stage. Although MMP9 has been reported to be involved in some physiological and pathological conditions through processing substrates, its role in tooth development and whether DSP is a substrate of MMP9 remain unknown. In this study, the function of MMP9 in the tooth development was examined by observation of Mmp9 knockout (Mmp9-/-) mouse phenotype, and whether DSP is a substrate of MMP9 was explored by in vitro and in vivo experiments. The results showed that Mmp9-/- teeth displayed a phenotype similar to Dentinogenesis imperfecta, including decreased Dentin mineral density, abnormal Dentin architecture, widened preDentin and irregular preDentin-Dentin boundary. The distribution of MMP9 and DSP overlapped in the odontoblasts, the preDentin, and the mineralized Dentin, and MMP9 was able to specifically bind to DSP. MMP9 highly efficiently cleaved DSP into distinct fragments in vitro, and the deletion of Mmp9 caused improper processing of DSP in natural teeth. Therefore, our findings demonstrate that MMP9 is important for tooth development and DSP is a novel target of MMP9 during Dentinogenesis.
-
phenotype characterization and dspp mutational analysis of three brazilian Dentinogenesis imperfecta type ii families
Cells Tissues Organs, 2009Co-Authors: Ana Carolina Acevedo, Juan Dong, L J S Santos, L M Paula, Mary MacdougallAbstract:The aim of this study was to perform phenotype analysis and Dentin sialophosphoprotein (DSPP) mutational analysis on 3 Brazilian families diagnosed with Dentinogenesis imperfecta type II (DGI-II) attending the Dental Anomalies Clinic in Brasilia, Brazil. Physical and oral examinations, as well as radiographic and histopathological analyses, were performed on 28 affected and unaffected individuals. Clinical, radiographic and histopathological analyses confirmed the diagnosis of DGI-II in 19 individuals. Pulp stones were observed in ground sections of several teeth in 2 families, suggesting that obliteration of pulp chambers and root canals results from the growth of these nodular structures. Mutational DSPP gene analysis of representative affected family members revealed 7 various non-disease-causing alterations in exons 1–4 within the Dentin Sialoprotein domain. Further longitudinal studies are necessary to elucidate the progression of pulpal obliteration in the DGI-II patients studied as well as the molecular basis of their disease.
-
Dentin Sialoprotein and Dentin Phosphoprotein Overexpression during Amelogenesis
Journal of Biological Chemistry, 2005Co-Authors: Michael L. Paine, Wen Luo, Hongjun Wang, Pablo Bringas, Amanda Y. W. Ngan, Vetea G. Miklus, Dan-hong Zhu, Mary Macdougall, Shane N. White, Malcolm L. SneadAbstract:Abstract The gene for Dentin sialophosphoprotein produces a single protein that is post-translationally modified to generate two distinct extracellular proteins: Dentin Sialoprotein and Dentin phosphoprotein. In teeth, Dentin sialophosphoprotein is expressed primarily by odontoblast cells, but is also transiently expressed by presecretory ameloblasts. Because of this expression profile it appears that Dentin sialophosphoprotein contributes to the early events of amelogenesis, and in particular to those events that result in the formation of the Dentino-enamel junction and the adjacent “aprismatic” enamel. Using a transgenic animal approach we have extended Dentin Sialoprotein or Dentin phosphoprotein expression throughout the developmental stages of amelogenesis. Overexpression of Dentin Sialoprotein results in an increased rate of enamel mineralization, however, the enamel morphology is not significantly altered. In wild-type animals, the inclusion of Dentin Sialoprotein in the forming aprismatic enamel may account for its increased hardness properties, when compared with bulk enamel. In contrast, the overexpression of Dentin phosphoprotein creates “pitted” and “chalky” enamel of non-uniform thickness that is more prone to wear. Disruptions to the prismatic enamel structure are also a characteristic of the Dentin phosphoprotein overexpressing animals. These data support the previous suggestion that Dentin Sialoprotein and Dentin phosphoprotein have distinct functions related to tooth formation, and that the Dentino-enamel junction should be viewed as a unique transition zone between enamel and the underlying Dentin. These results support the notion that the Dentin proteins expressed by presecretory ameloblasts contribute to the unique properties of the Dentino-enamel junction.
-
Dentin phosphoprotein compound mutation in Dentin sialophosphoprotein causes Dentinogenesis imperfecta type III.
American Journal of Medical Genetics Part A, 2004Co-Authors: Juan Dong, Leticia Jeffords, Mary MacdougallAbstract:A rare compound mutation involving a 36 bp deletion and 18 bp insertion within exon 5 of the Dentin sialophosphoprotein (DSPP) gene has been identified in a family with Dentinogenesis imperfecta type III (DGI-III). The DSPP gene encodes two major tooth matrix proteins Dentin Sialoprotein (DSP) and Dentin phosphoprotein (DPP). DSPP mutations associated with DGI-III results in an in frame truncation of the serine aspartic acid triplet repeat found in DPP near the highly conserved carboxyl terminal region shortening the protein by six amino acids. Clinically this family presents with discolored amber opalescent teeth and severe attrition of the tooth structure. This study is the first report of a mutation within DPP associated with a genetic Dentin disease. Our study indicates that DGI-III is allelic with some forms of DGI-II with and without progressive hearing loss and Dentin dysplasia type II that have been shown to be caused by mutations within the DSP coding or signal peptide regions.
Shuo Chen - One of the best experts on this subject based on the ideXlab platform.
-
Gelatinases Cleave Dentin Sialoprotein Intracellularly.
Frontiers in Physiology, 2020Co-Authors: Xiaohui Gou, Guobin Yang, Yifan Xue, Huiwen Zheng, Shuo Chen, Zhi Chen, Guohua YuanAbstract:Dentin Sialoprotein (DSP), the NH2-terminal fragment of Dentin sialophosphoprotein (DSPP), is essential for Dentin formation and further processed into small fragments inside the odontoblasts. Gelatinases, including matrix metalloproteinases 9 (MMP9) and MMP2, were able to cleave DSP(P) in tooth structures. We hypothesized that gelatinases may also cleave DSP intracellularly in the odontoblasts. In this study, the co-expression and physical interaction between DSP and gelatinases were proved by double immunofluorescence and in situ proximity ligation assay (PLA). Intracellular enzymatic activity of gelatinases was verified by gelatin zymography and in situ zymography. To confirm whether DSP was cleaved by active gelatinases intracellularly, lysates of wild-type (WT) odontoblastic cells treated with a MMP2 inhibitor or a MMP9 inhibitor or a MMP general inhibitor and of Mmp9-/- odontoblastic cells were analyzed by western blotting. Compared with the WT odontoblastic cells without inhibitor treatment, all these groups exhibited significantly higher ratios of high molecular weight to low molecular weight band density. FURIN was verified to be co-localized and physically interacted with MMP9 by double immunofluorescence and in situ PLA. The ratio of proMMP9 to activated MMP9 inside the odontoblastic cells were increased when function of endogenous FURIN was inhibited. And overexpressed proMMP9 was intracellularly cleaved by FURIN in the HEK293E cells, which was completely blocked by the mutation of proMMP9 with R96TPR99 substituted by A96AAA99. Taken together, these results indicate that DSP is intracellularly processed by gelatinases, and FURIN is involved in the intracellular activation of proMMP9 through cleavage of its R96TPR99 motif.
-
Dentin Sialoprotein facilitates dental mesenchymal cell differentiation and Dentin formation
Scientific Reports, 2017Co-Authors: Lei Chen, Mary Macdougall, Junsheng Feng, Kevin J. Donly, Zhuo Chen, Feng Wang, Lisa Shoff, Shuo ChenAbstract:Dentin Sialoprotein (DSP) is a Dentin extracellular matrix protein. It is involved in dental mesenchymal cell lineages and Dentin formation through regulation of its target gene expression. DSP mutations cause Dentin genetic diseases. However, mechanisms of DSP in controlling dental mesenchymal cell differentiation are unknown. Using DSP as bait, we screened a protein library from mouse odontoblastic cells and found that DSP is a ligand and binds to cell surface receptor, occludin. Further study identified that the C-terminal DSP domainaa 363–458 interacts with the occludin extracellular loop 2aa 194–241. The C-terminal DSP domain induced phosphorylation of occludin Ser490 and focal adhesion kinase (FAK) Ser722 and Tyr576. Coexpression of DSP, occludin and FAK was detected in dental mesenchymal cells during tooth development. Occludin physically interacts with FAK, and occludin and FAK phosphorylation can be blocked by DSP and occludin antibodies. This DSP domain facilitates dental mesenchymal cell differentiation and mineralization. Furthermore, transplantation and pulp-capping procedures revealed that this DSP domain induces endogenous dental pulp mesenchymal cell proliferation, differentiation and migration, while stimulating blood vessel proliferation. This study elucidates the mechanism of DSP in dental mesenchymal lineages and implies that DSP may serve as a therapeutic agent for Dentin-pulp complex regeneration in dental caries.
-
the Dentin Sialoprotein dsp domain regulates dental mesenchymal cell differentiation through a novel surface receptor
Scientific Reports, 2016Co-Authors: Guohua Yuan, Lei Chen, Guobin Yang, Chunyan Wan, Daoshu Luo, Lu Zhang, Heng Lin, Huan Liu, Shuo ChenAbstract:Dentin sialophosphoprotein (DSPP) is a Dentin extracellular matrix protein that is processed into Dentin Sialoprotein (DSP), Dentin glycoprotein (DGP) and Dentin phosphoprotein (DPP). DSP is mainly expressed in odontoblasts. We hypothesized that DSP interacts with cell surface receptors and subsequently activates intracellular signaling. Using DSP as bait for screening a protein library, we demonstrate that DSP acts as a ligand and binds to integrin β6. The 36 amino acid residues of DSP are sufficient to bind to integrin β6. This peptide promoted cell attachment, migration, differentiation and mineralization of dental mesenchymal cells. In addition, DSP aa183-219 stimulated phosphorylation of ERK1/2 and P38 kinases. This activation was inhibited by an anti-integrin β6 antibody and siRNA. Furthermore, we demonstrate that this DSP fragment induces SMAD1/5/8 phosphorylation and nuclear translocation via ERK1/2 and P38 signaling. SMAD1/5/8 binds to SMAD binding elements (SBEs) in the DSPP gene promoter. SBE mutations result in a decrease in DSPP transcriptional activity. Endogenous DSPP expression was up-regulated by DSP aa183-219 in dental mesenchymal cells. The data in the current study demonstrate for the first time that this DSP domain acts as a ligand in a RGD-independent manner and is involved in intracellular signaling via interacting with integrin β6. The DSP domain regulates DSPP expression and odontoblast homeostasis via a positive feedback loop.
-
immunohistochemical localization of the nh2 terminal and cooh terminal fragments of Dentin Sialoprotein in mouse teeth
Cell and Tissue Research, 2012Co-Authors: Guohua Yuan, Guobin Yang, Zhi Chen, Guangtai Song, Shuo ChenAbstract:Dentin Sialoprotein (DSP) is a major non-collagenous protein in Dentin. Mutation studies in human, along with gene knockout and transgenic experiments in mice, have confirmed the critical role of DSP for Dentin formation. Our previous study reported that DSP is processed into fragments in mouse odontoblast-like cells. In order to gain insights into the function of DSP fragments, we further evaluated the expression pattern of DSP in the mouse odontoblast-like cells using immunohistochemistry and western blot assay with antibodies against the NH2-terminal and COOH-terminal regions of DSP. Then, the distribution profiles of the DSP NH2-terminal and COOH-terminal fragments and osteopontin (OPN) were investigated in mouse teeth at different ages by immunohistochemistry. In the odontoblast-like cells, multiple low molecular weight DSP fragments were detected, suggesting that part of the DSP protein was processed in the odontoblast-like cells. In mouse first lower molars, immunoreactions for anti-DSP-NH2 antibody were intense in the preDentin matrix but weak in mineralized Dentin; in contrast, for anti-DSP-COOH antibody, strong immunoreactions were found in mineralized Dentin, in particular Dentinal tubules but weak in preDentin. Therefore, DSP NH2-terminal and COOH-terminal fragments from odontoblasts were secreted to different parts of teeth, suggesting that they may play distinct roles in Dentinogenesis. Meanwhile, both DSP antibodies showed weak staining in reactionary Dentin (RD), whereas osteopontin (OPN) was clearly positive in RD. Therefore, DSP may be less crucial for RD formation than OPN.
-
potential role of Dentin Sialoprotein by inducing dental pulp mesenchymal stem cell differentiation and mineralization for dental tissue repair
Dental Hypotheses, 2010Co-Authors: Guohua Yuan, Guobin Yang, Zhi Chen, Shuo ChenAbstract:INTRODUCTION: Dentin Sialoprotein (DSP) is a Dentin extracellular matrix protein, a unique marker of Dentinogenesis and plays a vital role in odontoblast differentiation and Dentin mineralization. Recently, studies have shown that DSP induces differentiation and mineralization of periodontal ligament stem cells and dental papilla mesenchymal cells in vitro and rescues Dentin deficiency and increases enamel mineralization in animal models. THE HYPOTHESIS: DSP as a nature therapeutic agent stimulates dental tissue repair by inducing endogenous dental pulp mesenchymal stem/progenitor cells into odontoblast-like cells to synthesize and to secrete Dentin extracellular matrix forming new tertiary Dentin as well as to regenerate a functional Dentin-pulp complex. As DSP is a nature protein, and clinical procedure for DSP therapy is easy and simple, application of DSP may provide a new avenue for dentists with additional option for the treatment of substantially damaged vital teeth. EVALUATION OF THE HYPOTHESIS: Dental caries is the most common dental disease. Deep caries and pulp exposure have been treated by various restorative materials with limited success. One promising approach is dental pulp stem/progenitor-based therapies to regenerate Dentin-pulp complex and restore its functions by DSP induction in vivo.
Euncheol Kim - One of the best experts on this subject based on the ideXlab platform.
-
combined effects of Dentin Sialoprotein and bone morphogenetic protein 2 on differentiation in human cementoblasts
Cell and Tissue Research, 2014Co-Authors: Soyoun Lee, Junhyeog Jang, Qschick Auh, Sookyung Kang, Hyung Joon Kim, Jungwoo Lee, Kwantae Noh, Euncheol KimAbstract:The aim of this study is to determine the effects of the combination of recombinant human BMP-2 (rh-BMP-2) and Dentin Sialoprotein (rh-DSP) on growth and differentiation in human cementoblasts and determine the underlying signal transduction mechanism. Compared to treatment of cementoblasts with either rh-BMP-2 or rh-DSP alone, the combination of rh-BMP-2 and rh-DSP synergistically increased cell growth, ALP activity, nodule formation and expression of differentiation markers.
-
effects of recombinant Dentin Sialoprotein in dental pulp cells
Journal of Dental Research, 2012Co-Authors: Sunju Lee, S Y Kim, Sunwoo Park, Joooh Kim, Junhyeog Jang, Euncheol KimAbstract:Dentin sialophosphoprotein (DSPP) is critical for Dentin mineralization. However, the function of Dentin Sialoprotein (DSP), the cleaved product of DSPP, remains unclear. This study aimed to investigate the signal transduction pathways and effects of recombinant human DSP (rh-DSP) on proliferation, migration, and odontoblastic differentiation in human dental pulp cells (HDPCs). The exogenous addition of rh-DSP enhanced the proliferation and migration of HDPCs in dose- and time-dependent manners. rh-DSP markedly increased ALP activity, calcium nodule formation, and levels of odontoblastic marker mRNA. rh-DSP increased BMP-2 expression and Smad1/5/8 phosphorylation, which was blocked by the BMP antagonist, noggin. Furthermore, rh-DSP phosphorylated extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK), Akt, and IκB-α, and induced the nuclear translocation of the NF-κB p65 subunit. Analysis of these data demonstrates a novel signaling function of rh-DSP for the promotion of growth, migra...
-
effect of mineral trioxide aggregate on Dentin bridge formation and expression of Dentin Sialoprotein and heme oxygenase 1 in human dental pulp
Journal of Endodontics, 2008Co-Authors: Kyungsan Min, Hyojin Park, Sunkyung Lee, Sanghyuk Park, Chanui Hong, Haewon Kim, Haehyoung Lee, Euncheol KimAbstract:This study was conducted to evaluate the pulpal response to direct capping with either mineral trioxide aggregate (MTA) or calcium hydroxide (CH) cement in humans, with a focus on Dentin bridge formation and Dentin Sialoprotein (DSP) and heme oxygenase-1 (HO-1) expression. Direct pulp capping was performed in 20 cases of caries-free human third molars. The pulps were exposed and capped with either MTA or hard-setting CH. After 2 months, the teeth were extracted, and the specimens were prepared for histologic and immunohistochemical evaluations. Histologically, 100% of the MTA group and 60% of the CH group developed Dentin bridges. The mean thickness of the Dentin bridges observed in the MTA group was statistically greater than that of CH group. In addition, DSP and HO-1 were expressed in the odontoblast-like cells and pulp fibroblasts beneath the Dentin bridge; furthermore, significantly greater immunostaining was observed in the MTA group than in the CH group. Collectively, these results indicate that MTA is superior to CH in terms of inducing the Dentinogenic process in human pulp capping.