Osteoblast(OBL) cells were isolated from ICR Swiss neonatal mouse calvarial tissues and cultured in a CO2 incubator with minimum essential medium (MEM) containing 0.25g BSA. The cells were cultured for 7 days and were treated with bovine parathyroid hormone (bPTH, 1-34) and calcitonin(CT). Enzyme activities related to mineral metabolism and other biochemical actions within the bone cells including protein phosphorylation were investigated. In other experiments using cultured calvarial bone tissues, hormones were treated for 24, 48, 72 or 96 hours. The activities of $\beta$-glucuronidase enzymes involved in bone collagen synthesis and mineral deposits were increased by 8% with bPTH and were inhibited with CT treatment, while those were 67% increase treated with bPTH and CT together. On the other hand, alkaline phophatase(AP) activities were inhibited by PTH hormone at all the time courses observed. Protein phosphorylation reaction in OBL was mediated by bPTH, cAMP and ionized Ca. Phosphorylation was observed in different cell fractions including homogenate, membrane and cytosol. The number of proteins phosphorylated by PTH, cAMP, and Ca were 10, 5, and 9, respectively. Most of the protein kinases(PKs) were existed in cytosolic compartment. In membrane fractions, two bPTH-dependent-PKs (70K, 50K Da) were observed of which 70K Da protein was also Ca-dependent. Most of the cAMP-dependent PKs were regulated via bPTH. 70K, 50K, 5K, 19K, 16K, 10.5K phosphoproteins regulated by Ca share the same pathways as those by bPTH-dependent proteins. Ca seems to regulate PK activities differently from cAMP.
Park, Young-Ju;Shin, Jin-Eob;Chung, Jae-An;Jeon, Min-Su;Kim, Bo-Gyun;Song, Jun-Ho;Yeon, Byong-Moo;Lim, Sung-Chul;Gang, Tae-In
Maxillofacial Plastic and Reconstructive Surgery
/
v.29
no.6
/
pp.474-484
/
2007
Purpose: The effect of platelet-rich plasma(PRP) on osteogenesis of marrow-derived osteoblasts on histomorphometric analysis in the mandible of rabbit was assessed. Materials and Method: Bone marrow cells were obtained from iliac bone of rabbits and were cultured in a Dulbecco's Modified Eagle's Medium(DMEM) with Dexamethasone, L-Ascortic acid, ${\beta}$-Glycerophosphate to proliferate and differentiate into osteoblasts for $4{\sim}5$ weeks. The expression of osteogenic mar-kers was detected by reverse transcription-polymerase chain reaction(RT-PCR) and silver nitrate stain. Then we prepared bony defects in the mandible of rabbit, 10.0mm in diameter and 4.0mm deep, by trephine bur. In the control group, the defects were filled with autogenous bone and cultured osteoblasts. In the experimental group, the defects were filled with autogenous bone, cultured osteoblasts and PRP. 2 weeks, 4 weeks, 8 weeks later, each group was evaluated with histological and histomorphometric analyses. Results: In vitro, osteoblasts were identified on RT-PCR and silver nitrate stain. According to histological observation, at 2 weeks well-developed anasto-mosing newly-formed woven bone was observed, at 4 weeks anastomosing newly-formed woven bone having osteoblastic activation was observed, and at 8 weeks thick newly-formed woven bone was observed in both control and experimental groups. According to histomorphometric analysis, there were 1.5% more newly-formed bone volume in experimental group than control group at 2 weeks, 28.4% more at 4 weeks, 4.3% more at 8 weeks. Particularly there were significant differences in bone volume at 4 weeks and 8 weeks new bone. Conclusion: Our results demonstrated PRP may enhance osteogenesis of marrow-derived osteoblasts at 4 weeks, 8 weeks.
Park, Bong-Wook;Byun, June-Ho;Ryu, Young-Mo;Hah, Young-Sool;Kim, Deok-Ryong;Cho, Yeong-Cheol;Sung, Iel-Yong;Kim, Jong-Ryoul
Maxillofacial Plastic and Reconstructive Surgery
/
v.29
no.3
/
pp.197-205
/
2007
Angiogenesis is a essential part for bone formation and bone fracture healing. Vascular endothelial growth factor (VEGF), one of the most important molecules among many angiogenic factors, is a specific mitogen for vascular endothelial cells. VEGF-mediated angiogenesis is required for bone formation and repair. However, the effect of VEGF on osteoblastic cells during osteogenesis is still controversial. In recent days, substantial progress have been made toward developing tissue-engineered alternatives to autologous bone grafting for maxillofacial bony defects. Periosteum has received considerable interest as a better source of adult stem cells. Periosteum has the advantage of easy harvest and contains various cell types and progenitor cells that are able to differentiate into a several mesenchymal lineages, including bone. Several studies have reported the bone formation potential of periosteal cells, however, the correlation between VEGF signaling and cultured human periosteal cell-derived osteogenesis has not been fully investigated yet. The purpose of this study was to examine the correlation between VEGF signaling and cultured human periosteal-derived cells osteogenesis. Periosteal tissues of $5\;{\times}\;20\;mm$ were obtained from mandible during surgical extraction of lower impacted third molar from 3 patients. Periosteal-derived cells were introduced into the cell culture and were subcultured once they reached confluence. After passage 3, the periosteal-derived cells were further cultured for 42 days in an osteogenic inductive culture medium containing dexamethasone, ascorbic acid, and ${\beta}-glycerophosphate$. We evaluated the alkaline phosphatase (ALP) activity, the expression of Runx2 and VEGF, alizarin red S staining, and the quantification of osteocalcin and VEGF secretion in the periosteal-derived cells. The ALP activity increased rapidly up to day 14, followed by decrease in activity to day 35. Runx2 was expressed strongly at day 7, followed by decreased expression at day 14, and its expression was not observed thereafter. Both VEGF 165 and VEGF 121 were expressed strongly at day 35 and 42 of culture, particularly during the later stages of differentiation. Alizarin red S-positive nodules were first observed on day 14 and then increased in number during the entire culture period. Osteocalcin and VEGF were first detected in the culture medium on day 14, and their levels increased thereafter in a time-dependent manner. These results suggest that VEGF secretion from cultured human periosteal-derived cells increases along with mineralization process of the extracellular matrix. The level of VEGF secretion from periosteal-derived cells might depend on the extent of osteoblastic differentiation.
Objectives : This study was performed to examine the effect of Yukmigiwhang-tang kamibang, a mixture of oriental herbal extracts, on the transcription of bone fonnation genes, BMP4 (bone morphogenetic protein 4) and TG2 (transglutaminase-2). Methods : Bone-related cells, MG-63 (human male osteosarcoma), HOS-TE85 (human female osteosarcoma), and KG-l (bone marrow) were cultured with portions of Yukmigiwhang-tang kamibang and the transcription activities of bone-related genes, BMP4 (bone morphogenetic protein 4) and TG2 (transglutaminase-2), were determined by Reverse-Transcription Polymerase Chain Reaction (RT-PCR). Results : Transcription of BMP4 gene in HOS-TE85 cell increased up to 40% at 0.3% (v/v) of Yukmigiwhang- tang kamibang extract and that of TG2 gene in MG-63 cells also increased up to 40% at 0.3-0.4% of the same extract. Although it was less significant when compared to those in other cells, the transcription of BMP4 gene in KG-l cells also increased up to 10 to 25%. Conclusions : These results clearly demonstrated that Yukmigiwhang-tang kamibang have an effect on transcription activity of bone-related genes, TG2 and BMP4, suggesting that it may play an important role in bone formation.
Journal of the Korean Association of Oral and Maxillofacial Surgeons
/
v.27
no.5
/
pp.453-456
/
2001
Background: Autogenous alveolar bone cell transplantation may be suitable for tissue engineering for alveolar bone reconstruction. This study aimed to isolate human alveolar bone-derived cells (HABDCs) and to evaluate the ability of collagen gels to support HABDC proliferation and differentiation for human alveolar bone tissue engineering applications. Method: Cultures of primary HABDCs were established from alveolar bone chips obtained from 10 persons undergoing tooth extraction. These cells were expanded in vitro until passage 3 and used for the in vitro characterization of HABDCs and the in vitro analysis of collagen gels for alveolar bone tissue engineering. Results: Of the 10 attempts made to obtain HABDC cultures, eight were successful. HABDCs expressed the osteoblastic phenotype characterized by alkaline phosphatase activity, osteocalcin expression and the mineralization of the extracellular matrix in vitro. When seeded on collagen gels, HABDCs penetrated into the collagen gel matrices and proliferated inside the gels. Significantly, when HABDCs were embedded into the gels, collagen fibers and mineralization were produced within the gels. Conclusion: This study demonstrates the feasibility of using cultured HABDCs and collagen gels for human alveolar bone tissue engineering applications.
DFDBA(Decalcified freeze-dried bone allograft) is one of the allograft materials for periodontal bone regeneration. DFDBA provides an osteoconductive surface and osteoinductive factors. Therefore, DFDBA have been used successfully to regenerate the attachment apparatus during periodontal treatment. But recent studies was reported that wide variations in commercial bone bank preparations of DFDBA do exist, including the ability to induce new bone formation. DFDBA was experimental materials that was recovered, processed, tested, shipped and invoiced through Musculoskeletal Transplant Foundation. MTF(Musculoskeletal Transplant Foundation) is the world largest, non-profit, AATB(American Association of Tissue Banks) accredited tissue bank. The objective of this study was to determine the effects of serial dilutions of a DFDBA on human fetal osteoblastic cell proliferation and their potential to form and mineralize bone nodules. Human fetal osteoblastic cell line(hFOB 1.19) was cultured with DMEM and SSE($1{\mu}g/m{\ell}$,$10{\mu}g/m{\ell}$, $100{\mu}g/m{\ell}$, $1mg/m{\ell}$) at $34^{\circ}C$ with 5% CO2 in 100% humidity. Cell proliferation was significantly increased at $1mg/m{\ell}$, $100{\mu}g$, $10{\mu}g/m{\ell}$, $1{\mu}g/m{\ell}$, $100ng/m{\ell}$, $10ng/m{\ell}$, $1ng/m{\ell}$ of DFDBA after 5 days incubation (p<0.05). Alkaline Phosphatase(ALP) level was significantly increased in $100ng/m{\ell}$, $10ng/m{\ell}$, $1ng/m{\ell}$ of DFDABA(p<0.05). A quantified calcium accumulation was significantly increased at $1ng/m{\ell}$, $10ng/m{\ell}$ of MTF(p<0.05). These results indicated that DFDBA has an inductive effect on bone formation in vitro.
Han, Seung-Kyu;Choi, Won Il;Lee, Byung Il;Kim, Woo Kyung
Archives of Plastic Surgery
/
v.34
no.4
/
pp.426-431
/
2007
Purpose: The aim of this study is to compare the effects of bone marrow stromal cells(BSCs) and fibroblasts on wound healing activity in vivo, especially on epithelization. Methods: The fibroblasts and BSCs were harvested from patients and cultured. Ten Spague-Dawley white rats were used. A 5 mm punches were made to excise skin and subcutaneous tissue in a round fashion at six sites on the back area of each rat. Four hundred thousand cells suspended in 0.05 ml fibrinogen were applied to the created wounds. The cells in group I, II, and III were no cells, fibroblasts and BSCs. The lengths of epithelial gap at the widest wound site were compared with autopsy specimens obtained on the 6th day after cell therapy under light microscope. Statistical comparisons were performed using the Mann-Whitney U-test, and the p value < 0.05 was considered statistically significant. Results: The best epithelization was also seen in the BSC group, followed by fibroblast and no cell groups.Conclusion: These results demonstrate that BSC has superior effect on stimulating wound healing than fibroblast, which is currently used for wound healing.
Bone morphogenetic protein-7(BMP-7), a member of the transforming growth factor superfamily, stimulates osteoblast differentiation and bone formation. There are lots of evidences supporting a direct participation of periodontal ligament(PDL) cells on periodontal tissue regeneration. The purpose of this study was to evaluate the effect of recombinant human(rh) BMP-7 on primary rat PDL cells in vitro, with special focus on the ability of bone formation. The PDL cells were cultured with rhBMP-7 at the concentration of 0, 10, 25, 50, 100 and 200ng/ml for MTT assay. We evaluated the alkaline phosphatase activity at 3 and 5 days of incubation and the ability to produce mineralized nodules of rat PDL cells at 14 days of cell culture in concentration of 0, 10, 25, 50 and 100ng/ml. The cell activity was not reduced in cells treated with BMP-7 at $10{\sim}100ng/ml$, whereas the cell activity was reduced in the concentration of 200ng/ml than the control at day 1 and 3(p<0.01). At 3 and 5 day, alkaline phosphatase activity was significantly increased in cells treated with BMP-7 at 50ng/ml and 100ng/ml(p<0.05). The area of mineralized bone nodule was greater in cells treated with BMP-7 at 50 and 100 ng/ml than the control(p<0.01). These results suggest that rhBMP-7 stimulate rat PDL cells to differentiate toward osteoblast phenotype and secretion of the extracellular matrix of rat PDL cells.
Park, Joon-Bong;Hur, In-Sik;Lee, Hye-Ja;Choi, Young-Chul
Journal of Periodontal and Implant Science
/
v.27
no.4
/
pp.949-961
/
1997
To date, various clinical procedures have been used to restore periodontal apparatus destroyed by periodontal disease. And then, many experimental approaches have been proceeded to develop treatment methods to promote periodontal regeneration. Mechanical, chemical treatments to enhance the attachment of periodontal tissue cells as changing the physical properties of root surfaces, bone graft procedure, and treatments for guided tissue regeneration have been used for periodontal regeneration. However, recent studies have revealed that biologic factors such as growth factors promote biologic mechanism associated with periodontal regeneration. This study was done to enucleate how ELF stimulus affect the periodontal regeneration. We can have following conclusions from this experimental results. The influence of low frequency(ELF) electric stimulus (30Hz at $lO{\mu}A$) known to promote bone formation in vivo, was evaluated for its ability to affect bone cell function in vitro. After 12 hour exposure of ELF stimulus at most appropriate densities ($5{\times}10^4\;cells/cm^2$) to increase osteoblastic cells normally, rat calvarial cells were incubated for 60 hours were used in this study. We have found ELF stimulus suppress calvarial cell proliferation and the ability of protein synthesis, enhance the alkaline phosphatase activity significantly.
Journal of the Korean Society of Food Science and Nutrition
/
v.39
no.2
/
pp.203-209
/
2010
In this study, the effects of Petasites japonicus and Momordica charantia L. extracts on MC3T3-ET1 osteoblastic cells were investigated. Since the activity of osteoblastic cell is one of the important factors for bone formation, the cellular proliferation of osteoblast was evaluated by MTT and alkaline phosphatase (ALP) activity. Compared to control, the cell proliferation was elevated to 114% and 112% by the treatment of Petasites japonicus and Momordica charantia L. extracts, respectively at the concentration of $10\;{\mu}g/mL$. The cell differentiation was also measured by alkaline phosphatase (ALP) activity at 3, 7, 14, and 27 days treatments with one of the extracts, respectively. As results, the ALP activity was significantly increased at 3 days, compared to control (p<0.05). To evaluate the effect of Petasites japonicus and Momordica charantia L. extracts on bone nodule formation, MC3T3-E1 cells were cultured in $\alpha$-MEM for 3, 14, and 21 days and then stained by alizarin red. To determine the expression patterns of bone-related proteins during the MC3T3-E1 osteoblast-like cell differentiation, osteoblast cells were cultured in $\alpha$-MEM for 24 hr. RNA was extracted and RT-PCR analysis was performed to examine the expression of OPG, RANKL and osteocalcin. Petasites japonicus extract exhibited the significant increment of osteocalcin compared with the positive control, which suggests that Petasites japonicus may have beneficial effects on bone health through the proliferation of osteoblast cells.
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