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Kodaira, Japan

Miyazaki T.,Tohoku University | Miyazaki T.,PG Research Co. | Miyauchi S.,PG Research Co. | Tawada A.,HYDROX Inc | And 2 more authors.
Dental Materials Journal | Year: 2010

The present study was designed to investigate whether chondroitin sulfate (CS)-E, a CS structural isomer variant, alter the differentiation of macrophage cell line RAW264 cells to osteoclast-like cells. CS-B, CS-E, low molecular weight CS-E, synthetic chondroitin polysulfate (CPS) and heparin significantly inhibited the formation of tartrate-resistant acid phosphatase-positive multinuclear cells and pit formation on calcium phosphate (CaP)-coated plates. CS-E pre-coated on the CaP plate also inhibited pit formation. Digestion of CS on the cell surface by chondroitinase showed no effect on the osteoclastic differentiation of RAW264 cells whereas inhibitory effect on the differentiation of osteoblastic cell line MC3T3-E1. On the other hand, exogenously added fluoresceinlabeled CS-E directory bound to fibronectin and RAW264 cells. These results suggest that CS-E structure on the surface of osteoblasts or bone matrix binds to cell adhesion molecule such as integrin on the pre-osteoclastic cells and inhibits the differentiation into osteoclasts. CS-E may have a potential in treating bone defect if combined with CaP materials. Source

Miyazaki T.,PG Research Co. | Miyauchi S.,PG Research Co. | Matsuzaka S.,PG Research Co. | Yamagishi C.,PG Research Co. | Kobayashi K.,Inoue Memorial Hospital
Tissue Engineering - Part A | Year: 2010

Tissue-engineered cartilage may be expected to serve as an alternative to autologous chondrocyte transplantation treatment. Several methods for producing cartilaginous tissue have been reported. In this study, we describe the production of scaffold-free stiff cartilaginous tissue of pig and human, using allogeneic serum and growth factors. The tissue was formed in a mold using chondrocytes recovered from alginate bead culture and maintained in a medium with transforming growth factor-β and several other additives. In the case of porcine tissue, the tear strength of the tissue and the contents of proteoglycan (PG) and collagen per unit of DNA increased dose-dependently with transforming growth factor-β. The length of culture was significantly and positively correlated with thickness, tear strength, and PG and collagen contents. Tear strength showed positive high correlations with both PG and collagen contents. A positive correlation was also seen between PG content and collagen content. Similar results were obtained with human cartilaginous tissue formed from chondrocytes expanded in monolayer culture. Further, an in vivo pilot study using pig articular cartilage defect model demonstrated that the cartilaginous tissue was well integrated with surrounding tissue at 13 weeks after the implantation. In conclusion, we successfully produced implantable scaffold-free stiff cartilaginous tissue, which characterized high PG and collagen contents. © 2010 Mary Ann Liebert, Inc. Source

Miyazaki T.,Tohoku University | Miyazaki T.,PG Research Co. | Miyauchi S.,PG Research Co. | Anada T.,Tohoku University | And 2 more authors.
Journal of Cellular Biochemistry | Year: 2015

Integrins and their ligands have been suggested to be associated with osteoclast-mediated bone resorption. The present study was designed to investigate whether chondroitin sulfate E (CS-E), which is one of the sulfated glycosaminoglycans (GAGs), is involved in osteoactivin (OA) activity, and osteoclast differentiation. The binding affinity of sulfated GAGs to integrin and its ligand was measured using biotin-labeled CS-E, and the osteoclast differentiation was evaluated by tartrate-resistant acid phosphatase staining and a pit formation assay. CS-E as well as CS-B, synthetic chondroitin polysulfate, and heparin inhibited osteoclast differentiation of bone marrow-derived macrophages. Pre-coating of OA to synthetic calcium phosphate-coated plates enhanced the osteoclastic differentiation of RAW264 cells, and addition of a neutralizing antibody to OA inhibited its differentiation. CS-E bound not only to OA, fibronectin, and vitronectin, but also to its receptor integrin αVβ3, and inhibited the direct binding of OA to integrin αVβ3. Furthermore, CS-E blocked the binding of OA to cells and inhibited OA-induced osteoclastic differentiation. On the other hand, heparinase treatment of RAW264 cells inhibited osteoclastic differentiation. Since binding of OA to the cells was inhibited by the presence of heparan sulfate or heparinase treatment of cells, heparan sulfate proteoglycan (HSPG) was also considered to be an OA receptor. Taken together, the present results suggest that CS-E is capable of inhibiting OA-induced osteoclast differentiation by blocking the interaction of OA to integrin αVβ3 and HSPG. J. Cell. Biochem. 116: 2247-2257, 2015. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc. Source

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