• 생명과학회지
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• 제10권2호
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• pp.218-227
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• 2000

Bone morphogenetic protein 1 (BMP-1) is part of a complex capable of inducing ectopic bone formation in mammals. Studies on TGF-β1 processing and Drosophila dorsal-ventral patterning have focused attention on BMP-1 as important in mediating the biological activity of this bone inducing complex. Herein, the bacterial expression, refolding, purification, and initial characterization of the BMP-1 proteolytic domain (BPD) are described. A semi-quantitative fluorescence-based thin layer chromatography assay was developed to assist in rapidly screening for optimal renaturation conditions. According to a preliminary screen for optimal conditions for the refolding of BPD , a detectable proteolytic activity against a high turnover substrate for astacin, a homologous protease from crayfish was observed. The conditions identified have allowed the expression of sufficient amounts of BPD for the characterization of the protein. Its proteolytic activity exhibits the same cleavage specificity as astacin against seven substrates that were previously synthesized for studying astacin. Furthermore, this activity is inhibited by the metal chelator 1,10-phenanthroline but not by its analogue 1,7-phenanthroline. The collagenase inhibitor Pro-Leu-Gly hydroxamate was found to inhibit both astacin and BPD activity. The results presented in this paper argue that BMP-1 does in fact possess an intrinsic proteolytic activity.

• Journal of Acupuncture Research
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• 제22권2호
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• pp.181-190
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• 2005

Background & Object : The differentiation of osteoblasts controlled by various growth factors and matrix proteins expression in bone. The aim of this study was to identify the Astragalus membranaceus that may induce the osteogenic activity in human osteoblast-like SaOS-2 cells. Methods : The osteogenic activity of Astragalus membranaceus were evaluated by WST-8 assay, ALP activity, RT-PCR analysis of VEGF, OCN, OPN, Col I mRNA, and ELISA or colorimetric analysis, and mineralization by Alizarin red staining in SaOS-2 cells. Results : Astragalus membranaceus had no effect on viability of osteoblastic cells, and dose dependently increased alkaline phosphatase (ALP) activity. Astragalus membranaceus markedly increased mRNA expression for vascular endothelial growth factor (VEGF), osteocalcin (OCN), osteopontin (OPN), and type I collagen (Col 1) in SaOS-2 cells. Extracellular accumulation of proteins such as VEGF, and Col I was increased in a dose-dependent manner. Also, Astragalus membranaceus significantly induced mineralization in the culture of SaOS-2 cells. Conclusion : This study showed that Astragalus membranaceus not affect on viability, but it enhanced ALP activity, VEGF, bone matrix proteins such as OCN, OPN and Col I, and mineralization in SaOS-2 cells. These results propose that Astragalus membranaceus plays an important role in osteoblastic bone formation, and possibly lead to the development of bone-forming drug.

• Journal of Korean Dental Science
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• 제5권1호
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• pp.21-28
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• 2012

Purpose: In this study the bone healing ability of autogenous tooth bone graft material as a substitute material was evaluated in a mini-pig cranial defect model through histologic examinations and osteonectin reverse transcription polymerase chain reaction (RT-PCR) quantitative analysis. Materials and Methods: A defect was generated in the cranium of mini-pigs and those without a defect were used as controls. In the experimental group, teeth extracted from the mini-pig were manufactured into autogenous tooth bone graft material and grafted to the defect. The mini-pigs were sacrificed at 4, 8, and 12 weeks to histologically evaluate bone healing ability and observe the osteonectin gene expression pattern with RT-PCR. Result: At 4 weeks, the inside of the bur hole showed fibrosis and there was no sign of bone formation in the control group. On the other hand, bone formation surrounding the tooth powder granule was observed at 4 weeks in the experimental group where the bur hole was filled with tooth powder. Osteonectin gene expression; there was nearly no osteonectin expression in the control group while active osteonectin expression was observed from 4 to 12 weeks in the experimental group. Conclusion: We believe this material will show better results when applied in a clinical setting.

• 대한한방부인과학회지
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• 제26권2호
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• pp.1-16
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• 2013

Objectives: This study was performed to evaluate the effect of Dokhwalgisaengtang-gami water extract(DGG) on osteoporosis. Methods: The osteoclastogenesis and gene expression were determined in RANKL-stimulated RAW 264.7 cell. And osteoblastogenesis was also determined in rat calvarial cell. Results: The results were summarized as followes. 1. DGG decreased the number of TRAP positive cell in RANKL-stimulated RAW 264.7 cell. 2. DGG inhibited TRAP activity in RANKL-stimulated RAW 264.7 cell. 3. DGG decreased the expression of NAFTc1, MITF in RANKL-stimulated RAW 264.7 cell. 4. DGG increased the expression of iNOS, COX-2, IL-6 in RANKL-stimulated RAW 264.7 cell. 5. DGG decreased the expression of cathepsin K, MMP-9, TRAP in RANKL-stimulated RAW 264.7 cell. 6. DGG increased cell proliferation of rat calvarial cell. 7. DGG increased ALP activity in rat calvarial cell 8. DGG increased bone matrix protein, collagen synthesis and nodule formation in rat calvarial cell. Conclusions: It is concluded that DGG might decrease the bone resorption resulted from decrease of osteoclast differentiation and it's related gene expression. And DGG might increase the bone formation resulted from increase of osteoblast function.

• International Journal of Oral Biology
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• 제33권1호
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• pp.33-43
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• 2008

In the process of bone remodeling, mineral phase of bone is dissolved by osteoclasts, resulting in elevation of calcium concentration in micro-environment. This study was performed to explore the effect of high extracellular calcium ($Ca{^{2+}}_e$) on mineralized nodule formation and on the expression of progressive ankylosis (Ank), plasma cell membrane glycoprotein-1 (PC-1) and osteopontin by primary cultured mouse calvarial cells. Osteoblastic differentiation and mineralized nodule formation was induced by culture of mouse calvarial cells in osteoblast differentiation medium containing ascorbic acid and ${\beta}$-glycerophosphate. Although Ank, PC-1 and osteopontin are well known inhibitors of mineralization, expression of these genes were induced at the later stage of osteoblast differentiation during when expression of osteocalcin, a late marker gene of osteoblast differentiation, was induced and mineralization was actively progressing. High $Ca{^{2+}}_e$(10 mM) treatment highly enhanced mRNA expression of Ank, PC-1 and osteopontin in the late stage of osteoblast differentiation but not in the early stage. Inhibition of p44/42 MAPK activation but not that of protein kinase C suppressed high $Ca{^{2+}}_{e^-}$induced expression of Ank, PC-1 and osteopontin. When high $Ca{^{2+}}_e$(5 mM or 10 mM) was present in culture medium during when mineral deposition was actively progressing, matrix calcifiation was significantly increased by high $Ca{^{2+}}_e$. This stimulatory effect was abolished by pyrophosphate (5 mM) or levamisole (0.1-0.5 mM), an alkaline phosphatase inhibitor. In addition, probenecid (2mM), an inhibitor of Ank, suppressed matrix calcification in both control and high $Ca{^{2+}}_{e^-}$treated group, suggesting the possible role of Ank in matrix calcification by osteoblasts. Taken together, these results showed that high $Ca{^{2+}}_e$ stimulates expression of Ank, PC-1 and osteopontin as well as matrix calcification in late differentiation stage of osteoblasts and that p44/42 MAPK activation is involved in high $Ca{^{2+}}_{e^-}$induced expression of Ank, PC-1 and osteopontin.

• BMB Reports
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• 제42권7호
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• pp.427-432
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• 2009

Orthodontic tooth movement results from the combinational process of both bone resorption and formation in the compressive and tension sides, respectively. However, the genes responsible for new bone formation in tension sides have not been determined. In this study, we used DNA microarray and real-time RT-PCR to identify genes in human periodontal ligament (PDL) cells that undergo significant changes in expression in response to static tensional forces (2 or 12 hours). The genes found were alkaline phospatase (ALP), matrix metalloproteinases (MMPs), vascular endothelial growth factor (VEGF), and several collagen genes. Furthermore, an ELISA evaluating the expression of VEGF, type IV collagen and MMP-2 found levels significantly increased after 24 and 72 hours (P < 0.05). ALP activity was also increased after 24 hours (P < 0.05). Collectively, we found the genes up-regulated in our study by the static tensional force are related to osteogenic processes such as matrix synthesis and angiogenesis.

• BMB Reports
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• 제55권12호
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• pp.627-632
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• 2022

Dickkopf-1 (DKK1) is a secreted protein that acts as an antagonist of the canonical WNT/β-catenin pathway, which regulates osteoblast differentiation. However, the role of DKK1 on osteoblast differentiation has not yet been fully clarified. Here, we investigate the functional role of DKK1 on osteoblast differentiation. Primary osteoprogenitor cells were isolated from human spinal bone tissues. To examine the role of DKK1 in osteoblast differentiation, we manipulated the expression of DKK1, and the cells were differentiated into mature osteoblasts. DKK1 overexpression in osteoprogenitor cells promoted matrix mineralization of osteoblast differentiation but did not promote matrix maturation. DKK1 increased Ca⁺ influx and activation of the Ca⁺/calmodulin-dependent protein kinase II Alpha (CAMK2A)-cAMP response element-binding protein 1 (CREB1) and increased translocation of p-CREB1 into the nucleus. In contrast, stable DKK1 knockdown in human osteosarcoma cell line SaOS2 exhibited reduced nuclear translocation of p-CREB1 and matrix mineralization. Overall, we suggest that manipulating DKK1 regulates the matrix mineralization of osteoblasts by Ca⁺-CAMK2A-CREB1, and DKK1 is a crucial gene for bone mineralization of osteoblasts.

• Journal of Acupuncture Research
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• 제24권5호
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• pp.13-22
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• 2007

Objectives : The differentiation of osteoblasts is controlled by various growth factors and matrix protein expressed in bone. The aim of this study was to investigate the effects of many herbs medicine(KHBJs) for bone healing that induces osteogenic activity in human osteoblast-like SaOS-2 cells. Methods : The osteogenic effects of KHBJs were evaluated by using cell proliferation(WST-8) assay, alkaline phosphatase(ALP) activity assay, colorimetric analysis of vascular endothelial growth factor(VEGF) expression in human osteoblast like SaOS-2 cell. Also, osteogenic activity of KHBJ fractions(KHBJB and KHBJR) by activity guided fractionation were evaluated. Results : About 7 KHBJs had effect on the proliferation of osteoblast like SaOS-2 cells, and dose-dependently increased alkaline phosphatase(ALP) activity. KHBJs markedly increased expression for VEGF. Fractionated KHBJs(KHBJB or KHBJR) not enhanced more than KHBJs on osteogenic activity in SaOS-2 cells. Conclusions: This study found that 7 KHBJs had effect on proliferation, ALP activity, and VEGF expression in osteoblast like SaOS-2 cells. These results propose that KHBJs can play an important role in osteoblastic bone formation, and may possibly lead to the development of bone-forming drugs.

• 치위생과학회지
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• 제9권4호
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• pp.427-433
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• 2009

본 연구는 상아모세포의 분화와 상아질 형성과정에서 필수적인 인자로 알려진 NFI-C가 상아모세포 기질단백질의 발현에 미치는 영향을 알아보기 위하여, MDPC-23 상아모세포에 NFI-C 유전자를 과발현 시키거나 발현억제시킨 후 상아질 기질단백질 유전자들의 발현을 RT-PCR로 분석한 결과 다음과 같은 결론을 얻었다. 1. MDPC-23 세포에서 NFI-C mRNA는 NFI-C 과발현후에 현저히 증가하였으며, NFI-C 발현억제 후에는 감소하였다. 2. NFI-C가 과발현된 MDPC-23 세포는 NFI-C 단백질이 핵과 세포질에서 뚜렷이 관찰되었으나, NFI-C 발현이 억제된 MDPC-23 세포에서는 NFI-C 단백질의 발현이 대조군에 비하여 현저히 감소하였다. 3. NFI-C 발현이 억제된 MDPC-23 세포는 대조군에 비하여 I형 아교질, OC, 및 DSPP mRNA의 발현은 감소하였으나 BSP의 발현은 증가하였다. ALP와 DMP4의 발현은 NFI-C 발현억제 후에도 변화가 없었다. 4. NFI-C가 과발현된 MDPC-23 세포에서는 ALP와 DMP4 mRNA의 발현은 대조군에 비하여 증가하였으며 I형 아교질, OC, DSPP, 및 BSP의 발현은 감소하였다.

• 대한치과의사협회지
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• 제46권8호
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• pp.494-504
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• 2008

Osseointegration is a result of bone formation and bone regeneration process, which take place at the interface between bone and implant and biologic determinants such as cytokine, growth factors, bone matrix proteins play an important role in osseointegration. The purpose of this study is to compare the expressoin of TGF-$\beta$, IGF-I, BMP2, BMP4 during osseointegration. We designed an experimental group which was inserted with a RBM surface titanium implants and machined surface, and compared with a control group which had a simple bone cavity and normal bone. Titanium implants were placed into tibia of 8 rabbits. We compared the expression of TGF-$\beta$, IGF-I, BMP2, BMP4 using RT_PCR (reverse transcriptase chain reaction)analysis in day 3,7,14 and 28 of implant insertion. According to the results, growth factors of experimental groups were more expressed than control groups. Among experimental groups, expression of TGF-$\beta$, IGF-I, BMP4 of BMP group had tedency to increase more at 14th, 28th days than Machined surface group. Therefore, our results suggest that TGF-$\beta$, IGF-I, BMP4 are expressed within the bone around the implant and more increased around rough surface implants while osseointegration occurs after dental implant insertion.