The Experts below are selected from a list of 20253 Experts worldwide ranked by ideXlab platform
Zhuxin Chen - One of the best experts on this subject based on the ideXlab platform.
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the in vivo Chondrogenesis of cartilage stem progenitor cells from auricular cartilage and the perichondrium
American Journal of Translational Research, 2019Co-Authors: Xiaodie Zhang, Zhezheng Xiong, Yahong Chen, Lin Qi, Junjie Li, Huizhong Zhang, Peng Xu, Zhuxin ChenAbstract:Bone marrow-derived stem cells are commonly studied for cartilage tissue engineering and regeneration medicine applications, but their ossification tendency and their limited capacity for chondrogenic differentiation depending on the donor age limit their clinical application. Cartilage stem/progenitor cells are ideal seeding cells, as cartilage stem/progenitor cells from auricular cartilage and the perichondrium have the inherent advantages of Chondrogenesis capacity and an easy and nontraumatic harvesting process, displaying promise for applications. The identification and comparison of cartilage stem/progenitor cells from auricular cartilage and the perichondrium in vitro were explored in our previous study, but the in vivo Chondrogenesis of these cells has not been fully examined. In the current study, we explored the ectopic Chondrogenesis of cartilage stem progenitor/cells from auricular cartilage and the perichondrium after chondrogenic induction in vitro. Our results suggest that stem/progenitor cells from auricular cartilage exhibit significantly better Chondrogenesis than those from the perichondrium in vivo, with upregulated chondrogenic genes and a stable cartilage phenotype, as well as good mechanical properties, indicating that stem/progenitor cells from auricular cartilage could be one type of ideal seeding cells for cartilage tissue engineering.
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The in vivo Chondrogenesis of cartilage stem/progenitor cells from auricular cartilage and the perichondrium.
American Journal of Translational Research, 2019Co-Authors: Xiaodie Zhang, Zhezheng Xiong, Yahong Chen, Lin Qi, Junjie Li, Huizhong Zhang, Peng Xu, Zhuxin ChenAbstract:Bone marrow-derived stem cells are commonly studied for cartilage tissue engineering and regeneration medicine applications, but their ossification tendency and their limited capacity for chondrogenic differentiation depending on the donor age limit their clinical application. Cartilage stem/progenitor cells are ideal seeding cells, as cartilage stem/progenitor cells from auricular cartilage and the perichondrium have the inherent advantages of Chondrogenesis capacity and an easy and nontraumatic harvesting process, displaying promise for applications. The identification and comparison of cartilage stem/progenitor cells from auricular cartilage and the perichondrium in vitro were explored in our previous study, but the in vivo Chondrogenesis of these cells has not been fully examined. In the current study, we explored the ectopic Chondrogenesis of cartilage stem progenitor/cells from auricular cartilage and the perichondrium after chondrogenic induction in vitro. Our results suggest that stem/progenitor cells from auricular cartilage exhibit significantly better Chondrogenesis than those from the perichondrium in vivo, with upregulated chondrogenic genes and a stable cartilage phenotype, as well as good mechanical properties, indicating that stem/progenitor cells from auricular cartilage could be one type of ideal seeding cells for cartilage tissue engineering.
Rocky S. Tuan - One of the best experts on this subject based on the ideXlab platform.
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transforming growth factor β mediated Chondrogenesis of human mesenchymal progenitor cells involves n cadherin and mitogen activated protein kinase and wnt signaling cross talk
Journal of Biological Chemistry, 2003Co-Authors: Richard Tuli, David J. Hall, Suraj Tuli, Sumon Nandi, Xiaoxue Huang, Paul A Manner, William J Hozack, Keith G Danielson, Rocky S. TuanAbstract:Abstract The multilineage differentiation potential of adult tissue-derived mesenchymal progenitor cells (MPCs), such as those from bone marrow and trabecular bone, makes them a useful model to investigate mechanisms regulating tissue development and regeneration, such as cartilage. Treatment with transforming growth factor-β (TGF-β) superfamily members is a key requirement for the in vitro chondrogenic differentiation of MPCs. Intracellular signaling cascades, particularly those involving the mitogen-activated protein (MAP) kinases, p38, ERK-1, and JNK, have been shown to be activated by TGF-βs in promoting cartilage-specific gene expression. MPC Chondrogenesis in vitro also requires high cell seeding density, reminiscent of the cellular condensation requirements for embryonic mesenchymal Chondrogenesis, suggesting common chondro-regulatory mechanisms. Prompted by recent findings of the crucial role of the cell adhesion protein, N-cadherin, and Wnt signaling in condensation and Chondrogenesis, we have examined here their involvement, as well as MAP kinase signaling, in TGF-β1-induced Chondrogenesis of trabecular bone-derived MPCs. Our results showed that TGF-β1 treatment initiates and maintains Chondrogenesis of MPCs through the differential chondro-stimulatory activities of p38, ERK-1, and to a lesser extent, JNK. This regulation of MPC chondrogenic differentiation by the MAP kinases involves the modulation of N-cadherin expression levels, thereby likely controlling condensation-like cell-cell interaction and progression to chondrogenic differentiation, by the sequential up-regulation and progressive down-regulation of N-cadherin. TGF-β1-mediated MAP kinase activation also controls WNT-7A gene expression and Wnt-mediated signaling through the intracellular β-catenin-TCF pathway, which likely regulates N-cadherin expression and subsequent N-cadherin-mediated cell-adhesion complexes during the early steps of MPC Chondrogenesis.
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Effect of cartilage oligomeric matrix protein on mesenchymal Chondrogenesis in vitro.
Osteoarthritis and cartilage, 2003Co-Authors: J Kipnes, Rocky S. Tuan, A.l Carlberg, G.a Loredo, Jack Lawler, David J. HallAbstract:Abstract Objective : Cartilage oligomeric matrix protein (COMP) mutations have been identified as responsible for two arthritic disorders, multiple epiphyseal dysplasia (MED) and pseudoachondroplasia (PSACH). However, the function of COMP in chondrogenic differentiation is largely unknown. Our investigation focuses on analyzing the function of normal COMP protein in cartilage biology. Methods and results : To explore the function of COMP we make use of an in vitro model system for Chondrogenesis, consisting of murine C3H10T1/2 mesenchymal cells maintained as a high-density micromass culture and stimulated with bone morphogenetic protein 2 (BMP-2). Under these culture conditions, C3H10T1/2 cells undergo active Chondrogenesis in a manner analogous to that of embryonic limb mesenchymal cells, and have been shown to serve as a valid model system to investigate the mechanisms regulating mesenchymal Chondrogenesis. Our results indicate that ectopic COMP expression enhances several early aspects of Chondrogenesis induced by BMP-2 in this system, indicating that COMP functions in part to positively regulate Chondrogenesis. Additionally, COMP has inhibitory effects on proliferation of cells in monolayer. However, at later times in micromass culture, ectopic COMP expression in the presence of BMP-2 causes an increase in apoptosis, with an accompanying reduction in cell numbers in the micromass culture. However, the remaining cells retain their chondrogenic phenotype. Conclusions : These data suggest that COMP and BMP-2 signaling converge to regulate the fate of these cells in vitro by affecting both early and late stages of Chondrogenesis.
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Wnt signaling during BMP-2 stimulation of mesenchymal Chondrogenesis.
Journal of cellular biochemistry, 2002Co-Authors: Leslie Fischer, Genevieve M. Boland, Rocky S. TuanAbstract:Members of both the Wnt and bone morphogenetic protein (BMP) families of signaling molecules have been implicated in the regulation of cartilage development. A key component of the Wnt signaling pathway is the cytosolic protein, β-catenin. We have recently shown that the chondrogenic activity of BMP-2 in vitro involves the action of the cell–cell adhesion protein, N-cadherin, which functionally complexes with β-catenin. The aim of this study is to test the hypothesis that Wnts may be involved in BMP-2 induced Chondrogenesis, using an in vitro model of high-density micromass cultures of the murine multipotent mesenchymal cell line, C3H10T1/2. Expression of a number of Wnt members was detected in these cultures, including Wnt-3A and Wnt-7A, whose levels were up- and downregulated, respectively, by BMP-2. To assess the functional involvement of Wnt signaling in BMP-2 induced Chondrogenesis, cultures were treated with lithium chloride, a Wnt-7A mimetic that acts by inhibiting the serine/threonine phosphorylation activity of glycogen synthase kinase-3β (GSK-3β). Lithium treatment significantly inhibited BMP-2 stimulation of Chondrogenesis as well as GSK-3β enzymatic activity, and decreased the levels of N-cadherin protein and mRNA. Furthermore, lithium decreased BMP-2 upregulation of total and nuclear levels of LEF-1 and β-catenin as well as their interaction during later Chondrogenesis; similarly, the interaction of β-catenin with N-cadherin was also decreased. Interestingly, lithium treatment did not affect the ability of BMP-2 to decrease ubiquitination of β-catenin, although it did reduce the interaction of β-catenin with GSK-3β during late Chondrogenesis (days 9–13). We suggest that the chondro-inhibitory effect of lithium on BMP-2 induced Chondrogenesis indicates antagonism between lithium-like Wnts and BMP-2 during mesenchymal condensation. J. Cell. Biochem. 84: 816–831, 2002. © 2002 Wiley-Liss, Inc.
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Chondrogenesis of neural crest cells: effect of poly-L-lysine and bone extract.
Differentiation; research in biological diversity, 1994Co-Authors: Sunetra Ekanayake, Rocky S. TuanAbstract:The mechanisms of chondrogenic differentiation are generally studied in vitro by analyzing the action of agents that promote or affect Chondrogenesis in embryonic mesenchyme, such as cells of the embryonic limb bud. However, it is not known whether progenitor cells of the craniofacial skeleton, which are of a different embryonic origin and derived from the neural crest, are similarly responsive to such agents. To gain insight into the regulation of chondrogenic differentiation in cells derived from neural crest, we have treated chick embryonic neural crest explants in vitro with poly-l-lysine (PL, Mr 380 kDa) or bovine bone extract (BBE), two agents known to enhance Chondrogenesis of limb mesenchymal cells. Both cephalic (normally chondrogenic) and trunk (normally nonchondrogenic) neural crest cells were analyzed. Chondrogenic differentiation was determined by histological, immunohistochemical and autoradiographic methods. Our results indicate that both PL (380 kDa) and BBE significantly enhance Chondrogenesis of cephalic neural crest cells, suggesting that the mechanism of Chondrogenesis of these ectodermally derived cells is similar to that of mesodermally derived limb mesenchymal cells. However, trunk neural crest cells did not undergo Chondrogenesis in response to PL or BBE. These data show that Chondrogenesis can be enhanced in cranial ectodermal neural crest cells in a manner similar to that in the limb mesenchyme. However, since nonchondrogenic trunk neural crest cells are not responsive, an inherent potential for cartilaginous differentiation is necessary for exogenous stimulation of Chondrogenesis.
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Expression and functional involvement of N-cadherin in embryonic limb Chondrogenesis
Development (Cambridge England), 1994Co-Authors: Steven A. Oberlender, Rocky S. TuanAbstract:Cell adhesion molecules have been shown to be important mediators of morphogenesis and pattern formation. In this study, we have shown that N-cadherin is expressed in a specific spatiotemporal manner in the developing limb bud during Chondrogenesis in vivo and in cultured limb mesenchyme in vitro. The time period of maximal expression of N-cadherin corresponds to the period of active cellular condensation, an event believed to be a necessary prerequisite for chondrogenic differentiation. To directly assess the functional involvement of N-cadherin in cellular condensation, we have examined the effects of perturbing N-cadherin activity on both cell aggregation and Chondrogenesis using NCD-2, a rat monoclonal antibody directed against the binding region of N-cadherin. Non-immune rat IgG was used as a control. Our results show that functional N-cadherin is necessary for Chondrogenesis to proceed both in vivo and in vitro. Limb mesenchymal cells exhibited characteristic Ca(2+)-dependent cell aggregation in suspension, which was inhibited in the presence of exogenous NCD-2. In micromass cultures of limb mesenchymal cells, NCD-2 inhibited overt Chondrogenesis in a dose-dependent manner. Furthermore, NCD-2 inhibition of Chondrogenesis in micromass cultures was time-dependent, suggesting that N-cadherin is crucially involved during the latter half of the first 24 hours of culture, a time period most likely corresponding to active cellular condensation. NCD-2 also significantly influenced limb development when injected into embryonic limb buds in vivo. In addition to significant inhibition of Chondrogenesis and developmental delays, gross developmental deformities and perturbation of overall pattern formation were also observed. Taken together, these results demonstrate that N-cadherin is functionally required in mediating the cell-cell interactions among mesenchymal cells important for Chondrogenesis in micromass culture in vitro and in the intact limb bud in vivo.
Xiaodie Zhang - One of the best experts on this subject based on the ideXlab platform.
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the in vivo Chondrogenesis of cartilage stem progenitor cells from auricular cartilage and the perichondrium
American Journal of Translational Research, 2019Co-Authors: Xiaodie Zhang, Zhezheng Xiong, Yahong Chen, Lin Qi, Junjie Li, Huizhong Zhang, Peng Xu, Zhuxin ChenAbstract:Bone marrow-derived stem cells are commonly studied for cartilage tissue engineering and regeneration medicine applications, but their ossification tendency and their limited capacity for chondrogenic differentiation depending on the donor age limit their clinical application. Cartilage stem/progenitor cells are ideal seeding cells, as cartilage stem/progenitor cells from auricular cartilage and the perichondrium have the inherent advantages of Chondrogenesis capacity and an easy and nontraumatic harvesting process, displaying promise for applications. The identification and comparison of cartilage stem/progenitor cells from auricular cartilage and the perichondrium in vitro were explored in our previous study, but the in vivo Chondrogenesis of these cells has not been fully examined. In the current study, we explored the ectopic Chondrogenesis of cartilage stem progenitor/cells from auricular cartilage and the perichondrium after chondrogenic induction in vitro. Our results suggest that stem/progenitor cells from auricular cartilage exhibit significantly better Chondrogenesis than those from the perichondrium in vivo, with upregulated chondrogenic genes and a stable cartilage phenotype, as well as good mechanical properties, indicating that stem/progenitor cells from auricular cartilage could be one type of ideal seeding cells for cartilage tissue engineering.
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The in vivo Chondrogenesis of cartilage stem/progenitor cells from auricular cartilage and the perichondrium.
American Journal of Translational Research, 2019Co-Authors: Xiaodie Zhang, Zhezheng Xiong, Yahong Chen, Lin Qi, Junjie Li, Huizhong Zhang, Peng Xu, Zhuxin ChenAbstract:Bone marrow-derived stem cells are commonly studied for cartilage tissue engineering and regeneration medicine applications, but their ossification tendency and their limited capacity for chondrogenic differentiation depending on the donor age limit their clinical application. Cartilage stem/progenitor cells are ideal seeding cells, as cartilage stem/progenitor cells from auricular cartilage and the perichondrium have the inherent advantages of Chondrogenesis capacity and an easy and nontraumatic harvesting process, displaying promise for applications. The identification and comparison of cartilage stem/progenitor cells from auricular cartilage and the perichondrium in vitro were explored in our previous study, but the in vivo Chondrogenesis of these cells has not been fully examined. In the current study, we explored the ectopic Chondrogenesis of cartilage stem progenitor/cells from auricular cartilage and the perichondrium after chondrogenic induction in vitro. Our results suggest that stem/progenitor cells from auricular cartilage exhibit significantly better Chondrogenesis than those from the perichondrium in vivo, with upregulated chondrogenic genes and a stable cartilage phenotype, as well as good mechanical properties, indicating that stem/progenitor cells from auricular cartilage could be one type of ideal seeding cells for cartilage tissue engineering.
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ISOLATION, CULTURE AND IDENTIFICATION OF CARTILAGE DERIVED STEM CELLS FROM THREE SUBTYPES OF CARTILAGES
Chinese Journal of Reparative and Reconstructive Surgery, 2015Co-Authors: Xiaodie ZhangAbstract:OBJECTIVE: To isolate and culture cartilage derived stem cells from different subtypes of cartilages, and to identify their characteristics. METHODS: Cartilage derived stem cells were isolated from different subtypes of cartilages (auricle cartilage, articular cartilage, and intervertebral cartilage) by using adhesive method of fibronectin. The expressions of positive surface markers (CD29 and CD90) and negative surface markers (CD34 and CD45) in cartilage derived stem cells were detected via flow cytometry. The single cell colony-forming efficiency of cartilage derived stem cells was determined by clonal formation unit test; the multipotent differentiation capacity was identified by chondrogensis, osteogenesis, and adipogenesis induction. RT-PCR was used to test the expression of osteogenic, chondrogenic, and adipogenic genes; and bone marrow mesenchymal stem cells (BMSCs) served as control. RESULTS: Three cell populations were successfully isolated from different subtypes of cartilages, which could express CD29 and CD 90 highly, but did not express CD34 and CD45. After 2 weeks of culture, single cartilage derived stem cell could form single cell colony. In addition, cartilage derived stem cells had high Chondrogenesis, osteogenesis, and adipogenesis potentials. After osteogenic induction, the expressions of collagen type I and collagen type X in articular and intervertebral cartilage stem cells were significantly higher than those in BMSCs (P 0.05). The expressions of Aggrecan and collagen type II in cartilage derived stem cells after chondrogenic induction were significantly higher than those in BMSCs (P 0.05). CONCLUSION: Cartilage derived stem cells in different subtypes of cartilages possess typical characteristics of stem cells.
Jang-soo Chun - One of the best experts on this subject based on the ideXlab platform.
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Cytokine-like 1 (Cytl1) regulates the Chondrogenesis of mesenchymal cells.
The Journal of biological chemistry, 2007Co-Authors: Jae-sung Kim, Zae Young Ryoo, Jang-soo ChunAbstract:Abstract To identify novel molecules regulating Chondrogenesis and cartilage development, we screened a cartilage-specific expressed sequence tag data base. Cytokine-like 1 (Cytl1), a possible cytokine candidate with unknown function that was originally identified in bone marrow-derived CD34-positive cells, was selected for functional characterization. In view of the initial observation that Cytl1 is predominantly expressed in chondrocytes and cartilage, we investigated its possible role in Chondrogenesis and hypertrophic maturation of chondrocytes. Cytl1 expression was very low in mesenchymal cells, dramatically increased during Chondrogenesis, and decreased during hypertrophic maturation, both in vivo and in vitro. The role of Cytl1 in Chondrogenesis and hypertrophic maturation was examined by treating chondrifying mesenchymal cells with exogenous Cytl1 or ectopic expression of Cytl1. Notably, exogenous Cytl1 caused chondrogenic differentiation of mouse limb bud mesenchymal cells during micromass culture. Lentivirus-mediated overexpression of Cytl1 additionally induced chondrogenic differentiation of mesenchymal cells. However, Cytl1 did not affect the hypertrophic maturation of chondrocytes. Cytl1 exerted its chondrogenic effect via stimulation of Sox9 transcriptional activity. In addition, Cytl1 caused expression of insulin-like growth factor 1, which has a capacity to induce Chondrogenesis. Thus, our results collectively suggest that chondrocyte-specific Cytl1 regulates Chondrogenesis as a novel autocrine factor, but not hypertrophic maturation of chondrocytes during cartilage development.
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Under-sulfation by PAPS synthetase inhibition modulates the expression of ECM molecules during Chondrogenesis.
Biochemical and biophysical research communications, 2004Co-Authors: Young Rae Cho, Jang-soo Chun, Sun-joo Lee, Hong Bae Jeon, Zee Yong Park, Yung Joon YooAbstract:Abstract Sulfation of proteoglycans is an important post-translational modification in chondrocytes. We previously found that 3′-phosphoadenosine 5′-phosphosulfate (PAPS) synthetase-2 levels increased more than 10-fold during mesenchymal cell Chondrogenesis. Given that PAPS is the sole sulfur donor, and is produced only by PAPS synthetase in all cells, increased expression of PAPS synthetase-2 should be a prerequisite for increased sulfation activity of chondrocytes. We found that sodium chlorate, a specific inhibitor of PAPS synthetase, inhibited proteoglycan sulfation during Chondrogenesis. In contrast, sodium chlorate unexpectedly induced early expression of type II collagen and increased the number of cartilage nodules during Chondrogenesis. Inhibition of sulfation also accelerated the down-regulation of N-cadherin and fibronectin during Chondrogenesis. These findings suggest that sulfation has an important regulatory role in coordinating the timely expression of extracellular matrix molecules during Chondrogenesis, and that under-sulfation may cause the breakdown of this coordination, leading to premature Chondrogenesis.
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Identification of proteins differentially expressed during Chondrogenesis of mesenchymal cells.
FEBS Letters, 2004Co-Authors: Sun-joo Lee, Jang-soo Chun, Hong Bae Jeon, Jeung Hwa Lee, Jong Shin Yoo, Yung Joon YooAbstract:We performed comparative proteome analysis of mesenchymal cells and chondrocytes to identify proteins differentially expressed during Chondrogenesis. Nine such proteins were identified. Type II collagen, matrilin-1, carbonic anhydrase-II (CA-II), 3'-phosphoadenosine 5'-phosphosulfate (PAPS) synthetase-2, and aldo-keto reductase were increased during Chondrogenesis, whereas cellular retinoic acid binding protein-I (CRABP-I), CRABP-II, cytoplasmic type 5 actin, and fatty acid binding protein were decreased or almost disappeared. Expression of type II collagen, matrilin-1, PAPS synthetase-2, and CA-II was regulated by extracellular signal-regulated protein kinase, protein kinase C, and p38 kinase, signaling molecules known to regulate Chondrogenesis.
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Opposing Role of Mitogen-activated Protein Kinase Subtypes, Erk-1/2 and p38, in the Regulation of Chondrogenesis of Mesenchymes
The Journal of biological chemistry, 2000Co-Authors: Sung-hee Chang, Young-mee Yoon, Su-jae Lee, Yun-sil Lee, Shin-sung Kang, Jang-soo ChunAbstract:Abstract The present studies were performed to determine subtype-specific roles of mitogen-activated protein kinase in Chondrogenesis. Erk-1/2 activities, downstream of protein kinase C, decreased as Chondrogenesis proceeded, whereas p38 activities, independent of protein kinase C, continuously increased during Chondrogenesis. Inhibition of Erk-1/2 with PD98059 enhanced Chondrogenesis up to 1.7-fold, whereas inhibition of p38 with SB203580 reduced it to about 30% of the control level. Inhibition of Erk-1/2 or p38 did not affect precartilage condensation. However, cartilage nodule formation was significantly blocked by the inhibition of p38, whereas Erk-1/2 inhibition did not affect it. Modulation of Chondrogenesis by the inhibition of Erk-1/2 and p38 was accompanied by altered expression of adhesion molecules in an opposite way. Expression ofN-cadherin was reduced as Chondrogenesis proceeded. Inhibition of p38 caused sustained expression ofN-cadherin, whereas Erk-1/2 inhibition accelerated the reduction of N-cadherin expression. Expression of integrin α5β1 and fibronectin were found to transiently increase during Chondrogenesis. Inhibition of p38 caused continuous increase of expression of these molecules, whereas Erk-1/2 inhibition accelerated the decrease of expression of these molecules at a later period of Chondrogenesis. Because temporal expression of these adhesion molecules regulates Chondrogenesis, the above results indicate that Erk-1/2 and p38 conversely regulate Chondrogenesis at post-precartilage condensation stages by modulating expression of adhesion molecules.
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Protein kinase C regulates Chondrogenesis of mesenchymes via mitogen-activated protein kinase signaling.
The Journal of biological chemistry, 1998Co-Authors: Sung-hee Chang, Shin-sung Kang, Young-sup Lee, Jong-kyung Sonn, Myung-soon Yang, Jang-soo ChunAbstract:Abstract A possible regulatory mechanism of protein kinase C (PKC) in the Chondrogenesis of chick limb bud mesenchymes has been investigated. Inhibition or down-regulation of PKC resulted in the activation of a mitogen-activated protein kinase subtype Erk-1 and the inhibition of Chondrogenesis. On the other hand, inhibition of Erk-1 with PD98059 enhanced Chondrogenesis and relieved PKC-induced blockage of Chondrogenesis. Erk-1 inhibition, however, did not affect expression and subcellular distribution of PKC isoforms expressed in mesenchymes nor cell proliferation. The results suggest that PKC regulates Chondrogenesis by modulating Erk-1 activity. Inhibition or depletion of PKC inhibited proliferation of chondrogenic competent cells, and Erk-1 inhibition did not affect PKC modulation of cell proliferation. However, PKC-induced modulation of expression of cell adhesion molecules involved in precartilage condensation was reversed by the inhibition of Erk-1. Expression of N-cadherin was detected at the early period of Chondrogenesis. Inhibition or depletion of PKC induced sustained expression of N-cadherin, and Erk-1 inhibition blocked the effects of PKC modulation. The expression of integrin α5β1 and fibronectin was found to be increased transiently during Chondrogenesis. Depletion or inhibition of PKC caused a continuous increase of the expression of these molecules throughout the culture period, and Erk-1 inhibition abolished the modulating effects of PKC. Because reduction of the examined cell adhesion molecule expression is a prerequisite for the progression of Chondrogenesis after cell condensation, our results indicate that PKC regulates Chondrogenesis by modulating expression of these molecules via Erk-1 signaling.
Jong-kyung Sonn - One of the best experts on this subject based on the ideXlab platform.
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Rac1 promotes Chondrogenesis by regulating STAT3 signaling pathway
Cell biology international, 2016Co-Authors: Hyoin Kim, Jong-kyung SonnAbstract:The small GTPase protein Rac1 is involved in a wide range of biological processes including cell differentiation. Previously, Rac1 was shown to promote Chondrogenesis in micromass cultures of limb mesenchyme. However, the pathways mediating Rac1's role in Chondrogenesis are not fully understood. This study aimed to explore the molecular mechanisms by which Rac1 regulates chondrogenic differentiation. Phosphorylation of signal transducer and activator of transcription 3 (STAT3) was increased as Chondrogenesis proceeded in micromass cultures of chick wing bud mesenchyme. Inhibition of Rac1 with NSC23766, janus kinase 2 (JAK2) with AG490, or STAT3 with stattic inhibited Chondrogenesis and reduced phosphorylation of STAT3. Conversely, overexpression of constitutively active Rac1 (Rac L61) increased phosphorylation of STAT3. Rac L61 expression resulted in increased expression of interleukin 6 (IL-6), and treatment with IL-6 increased phosphorylation of STAT3. NSC23766, AG490, and stattic prohibited cell aggregation, whereas expression of Rac L61 increased cell aggregation, which was reduced by stattic treatment. Our studies indicate that Rac1 induces STAT3 activation through expression and action of IL-6. Overexpression of Rac L61 increased expression of bone morphogenic protein 4 (BMP4). BMP4 promoted Chondrogenesis, which was inhibited by K02288, an activin receptor-like kinase-2 inhibitor, and increased phosphorylation of p38 MAP kinase. Overexpression of Rac L61 also increased phosphorylation of p38 MAPK, which was reduced by K02288. These results suggest that Rac1 activates STAT3 by expression of IL-6, which in turn increases expression and activity of BMP4, leading to the promotion of Chondrogenesis.
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Inhibition of RhoA but not ROCK induces Chondrogenesis of chick limb mesenchymal cells.
Biochemical and biophysical research communications, 2012Co-Authors: Min Jung Kim, Sunhyo Kim, Youngshin Kim, Eun-jung Jin, Jong-kyung SonnAbstract:Cell shape change and cytoskeletal reorganization are known to be involved in the Chondrogenesis. Negative role of RhoA, a cytoskeleton-regulating protein, and its downstream target, Rho-associated protein kinase (ROCK) in the Chondrogenesis has been studied in many different culture systems including primary chondrocytes, chondrogenic cell lines, dedifferentiated chondrocytes, and micromass culture of mesenchymal cells. To further investigate the role of RhoA and ROCK in the Chondrogenesis, we examined the RhoA-ROCK-myosin light chains (MLC) pathway in low density culture of chick limb bud mesenchymal cells. We observed for the first time that inhibition of RhoA by C3 cell-permeable transferase, CT04, induced Chondrogenesis of undifferentiated mesenchymal single cells following dissolution of actin stress fibers. Inhibition of RhoA activity by CT04 was confirmed by pull down assay using the Rho-GTP binding domain of Rhotekin. CT04 also inhibited ROCK activity. In contrast, inhibition of ROCK by Y27632 neither altered the actin stress fibers nor induced Chondrogenesis. In addition, inhibition of RhoA or ROCK did not affect the phosphorylation of MLC. Inhibition of myosin light chain kinase (MLCK) by ML-7 or inhibition of myosin ATPase with blebbistatin dissolved actin stress fibers and induced Chondrogenesis. ML-7 reduced the MLC phosphorylation. Taken together, our current study suggests that RhoA uses other pathway than ROCK/MLC in the modulation of actin stress fibers and Chondrogenesis. Our data also imply that, irrespective of mechanisms, dissolution of actin stress fibers is crucial for Chondrogenesis.
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Protein kinase C regulates Chondrogenesis of mesenchymes via mitogen-activated protein kinase signaling.
The Journal of biological chemistry, 1998Co-Authors: Sung-hee Chang, Shin-sung Kang, Young-sup Lee, Jong-kyung Sonn, Myung-soon Yang, Jang-soo ChunAbstract:Abstract A possible regulatory mechanism of protein kinase C (PKC) in the Chondrogenesis of chick limb bud mesenchymes has been investigated. Inhibition or down-regulation of PKC resulted in the activation of a mitogen-activated protein kinase subtype Erk-1 and the inhibition of Chondrogenesis. On the other hand, inhibition of Erk-1 with PD98059 enhanced Chondrogenesis and relieved PKC-induced blockage of Chondrogenesis. Erk-1 inhibition, however, did not affect expression and subcellular distribution of PKC isoforms expressed in mesenchymes nor cell proliferation. The results suggest that PKC regulates Chondrogenesis by modulating Erk-1 activity. Inhibition or depletion of PKC inhibited proliferation of chondrogenic competent cells, and Erk-1 inhibition did not affect PKC modulation of cell proliferation. However, PKC-induced modulation of expression of cell adhesion molecules involved in precartilage condensation was reversed by the inhibition of Erk-1. Expression of N-cadherin was detected at the early period of Chondrogenesis. Inhibition or depletion of PKC induced sustained expression of N-cadherin, and Erk-1 inhibition blocked the effects of PKC modulation. The expression of integrin α5β1 and fibronectin was found to be increased transiently during Chondrogenesis. Depletion or inhibition of PKC caused a continuous increase of the expression of these molecules throughout the culture period, and Erk-1 inhibition abolished the modulating effects of PKC. Because reduction of the examined cell adhesion molecule expression is a prerequisite for the progression of Chondrogenesis after cell condensation, our results indicate that PKC regulates Chondrogenesis by modulating expression of these molecules via Erk-1 signaling.
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Expression of Protein Kinase C Isozymes That Are Required for Chondrogenesis of Chick Limb Bud Mesenchymal Cells
Biochemical and biophysical research communications, 1995Co-Authors: Bohm Choi, Jang-soo Chun, Young-sup Lee, Jong-kyung Sonn, Shin-sung KangAbstract:Protein kinase C (PKC) has been suggested to be involved in the Chondrogenesis of chick limb bud mesenchymal cells. This study examined the expression and the role of PKC isozymes in Chondrogenesis. Multiple PKC isozymes such as conventional PKC (cPKC alpha and gamma), new PKC (nPKC epsilon), and atypical PKC (aPKC zeta, lambda, and tau) were expressed in chondroblasts but cPKC beta and nPKC delta were not detected. The amounts of expressed cPKC and nPKC isozymes, namely cPKC alpha and gamma and nPKC epsilon, were increased as Chondrogenesis proceeds while the level of aPKC isozymes was not changed. Treatment of cells with specific PKC inhibitors blocked Chondrogenesis. Prolonged exposure of cells to phorbol ester which down regulates both cPKC and nPKC also blocked chondrogenic differentiation. The inhibition of Chondrogenesis was the most effective when PKC activity was blocked at the early stage of Chondrogenesis (i.e., for the first 24 hours of micromass culture). Down regulation of PKC blocked both proliferation of cells and synthesis of sulfated proteoglycans, indicating that expression of cPKC and nPKC is required at early stage of Chondrogenesis.