• Journal of Life Science
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• v.33 no.11
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• pp.851-858
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• 2023

Unique cartilage matrix-associated protein (UCMA) is an extrahepatic vitamin K-dependent protein rich in γ-carboxylated (Gla) residues. UCMA has been recognized for its ability to promote osteoblast differentiation and enhance bone formation; however, its impact on osteoblasts under hyperglycemic stress remains unknown. In this paper, we investigated the effect of UCMA on MC3T3-E1 osteoblastic cells under hyperglycemic conditions. After exposure to high glucose, the MC3T3-E1 cells were treated with recombinant UCMA proteins. CellROX and MitoSOX staining showed that the production of reactive oxygen species (ROS), which initially increased under high-glucose conditions in MC3T3-E1 cells, decreased after UCMA treatment. Additionally, quantitative polymerase chain reaction revealed increased expression of antioxidant genes, nuclear factor erythroid 2-related factor 2 and superoxide dismutase 1, in the MC3T3-E1 cells exposed to both high glucose and UCMA. UCMA treatment downregulated the expression of heme oxygenase-1, which reduced its translocation from the cytosol to the nucleus. Moreover, the expression of dynamin-related protein 1, a mitochondrial fission marker, was upregulated, and AKT signaling was inhibited after UCMA treatment. Overall, UCMA appears to mitigate ROS production, increase antioxidant gene expression, impact mitochondrial dynamics, and modulate AKT signaling in osteoblasts exposed to high-glucose conditions. This study advances our understanding of the cellular mechanism of UCMA and suggests its potential use as a novel therapeutic agent for bone complications related to metabolic disorders.

• Journal of Life Science
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• v.20 no.4
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• pp.607-613
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• 2010

Osteoporosis is a disease involving a decrease in bone mineral density and an increased risk of fractures. The MC3T3-E1 pre-osteoblastic cell line is a well-accepted model of osteogenesis in vitro. Pine needles have long been used as a traditional health-promoting medicinal food in Korea. In this study, MTT assay, the alkaline phosphatase (ALP) activity and collagen synthesis of osteoblast cells were investigated to determine the effects of pine needle extracts on cell proliferation and differentiation. Pine needle extracts were prepared using hexane, ethanol and water. The effects of the pine needle extracts were examined by comparing the results with those of commercial agents, such as proanthocyanidin. The MC3T3-E1 cells exposed to proanthocyanidin showed increased proliferation in a concentration-dependent manner. The cells exposed to the hexane extract showed a similar increase in proliferation to that observed with proanthocyanidin. The hexane extract showed the highest ALP activity. Moreover, a supplement of pine needle extracts induced collagen synthesis in MC3T3-E1 cells. The pine needle extract produced the highest level of collagen synthesis at concentrations of $10{\sim}50\;{\mu}g/ml$. These results indicate that pine needle extracts have an anabolic effect on bone by promoting osteoblastic differentiation, and may be used in the treatment of common metabolic bone diseases.

• Journal of the korean academy of Pediatric Dentistry
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• v.28 no.2
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• pp.207-218
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• 2001

The purpose of this study was to investigate the direct inhibitory effect of calcium hydroxide materials on differentiation and activation of osteoclast. we used the osteoclast progenitor cells isolated from bone marrow cell of chick embryo tibia and four experimental materials [$Ca(OH)_2$ powder, Metapaste$^{(R)}$, Vitapex$^{(R)}$, Pulpdent$^{(R)}$] diluted at 0.1, 0.01, $0.05{\mu}g/ml$. There were measured both the number of differentiated osteoclast and the area of resorption lacunae. Also, we conducted MTT assay on U2OS osteoblast to examine of cytotoxic effect and obtained following result. 1. Considering the result of the inhibitory effects upon osteoclast differentiation, There were shown a significant difference increased in the following order: Metapaste$^{(R)}$, $Ca(OH)_2$ powder, Vitapex$^{(R)}$. But no significant difference was found in pulpdent group that the number of differentiated osteoclast was increased at all concentrations(p<0.05). 2. Among the three experimental groups, that is, $Ca(OH)_2$ powder, Metapaste$^{(R)}$, Vitapex$^{(R)}$ at $0.1{\mu}g/ml$ dilution that were statistically significant in reduction of the number of differentiated osteoclast. Vitapex group showed significant cytotoxic effect compared to control and another two groups exhibited no significant difference. Also, 0.2% DMSO group was shown statistically siginificant cytotoxicity (p<0.05). 3. Examining pattern and measured area of resorption lacunae in the control and the three experimental groups ,that is, $Ca(OH)_2$ powder, Metapaste$^{(R)}$, Vitapex$^{(R)}$ at $0.1{\mu}g/ml$ dilution, except $Ca(OH)_2$ powder group, statistically significant differences were found between experimental groups and control group. Also, DMSO group showed statistically significant decrease (p<0.05). From these results, we think that calcium hydroxide is responsible for suppression of hard tissue resorption by a direct inhibition of dfferentiation and activation of osteoclast.

• Journal of Periodontal and Implant Science
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• v.33 no.3
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• pp.457-474
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• 2003

The ultimate objective of periodontal treatment is to get rid of an on-going periodontal disease and further regenerate the supporting tissue, which is already destroyed, functionally. Currently, the bone grafting operation using various kinds of bone grafting materials and the operation for induced regeneration of periodontal tissue using the blocking membrane are performed for regeneration of the destroyed periodontal tissue. However, there are respective limitations Galenical preparations, which are used for regeneration of periodontal of tissue, has less risk of rejective reaction or toxicity that may be incidental to degradation and their effect is sustainable. Thus, in case they are applicable to a clinic, they can he used economically. Chitosan has such compatibility, biological actions including antibacterial activity, acceleration of wound treatment, etc., and excellent mechanical characteristics, which has recently aroused more interest in it. Also, it has been reported that it promotes osteogenesis directly or indirectly by functioning as a matrix to promote migration and differentiation of a specific precussor cell (for example, osteoblast) and further inhibiting the function of such a cell as fibroblast to prevent osteogenesis. In this study, the pure chitosan solution, which was obtained by purifying chitosan, was used. However, since this chitosan is of a liquiform, it is difficult to sustain it in a defective region. It is, therefore, essential to use a carrier for delivering chitosan to, and sustaining it gradually in the defective region. In the calvarial defect model of the Sprague-Dawley rat, it is relatively easy to maintain a space. Therefore, in this study, the chitosan solution with which ACS was wetted was grafted onto the defective region, For an experimental model, a calvarial defect of rat m s selected, and a critical size of the defective region was a circular defect with a diameter of 8 mm. A group in which no treatment was conducted for the calvarial defect was set as a negative control group. Another group in which treatment was conducted with ACS only was set as a positive control group (ACS group). And another group in which treatment was conducted was conducted with by grafting the pure chitosan solution onto the defective region through ACS which was wetted with the chitosan solution was set an experimental group (Chitosan/ACS group). Chitosan was applied to the Sprague-Dawley rat's calvarial bone by applying ACS which was wetted with the chitosan solution, and each Sprague-Dawley rat was sacrificed respectively 2 weeks and 8 weeks after the operation for such application. Then, the treatment results were compared and observed histologically and his tometrically. Thereby, the following conclusions were obtained. 1. In the experimental group, a pattern was shown that from 2 weeks after the operation, vascular proliferation proceeded and osteogenesis proceeded through osteoblast infiltration, and at 8 week after the operation, ACS was almost absorbed, the amount of osteogensis was increased and many osteoid tissue layers were observed. 2. At 2 weeks after the operation, each amount of osteogenesis appeared to be 8.70.8 %, 13.62.3 % and 4.80.7 % respectively in the experimental group, the positive control group and the negative control group. Accordingly, it appeared to be higher in the Experimental group and the positive control group than in the negative control group, but there was no significant difference statistically (p<0.01). 3. At 8 weeks after the operation, each amount of osteogenesis appeared to be 62.26.1%, 17.42.5 % and 8.21.4 % respectively in the experimental group, the positive control group and the negative control group. Accordingly, it appeared to be substantially higher in the experimental group than in the positive control group and the negative control group, and there was a significant difference statistically (p<0.01). As a result of conducting the experiment, when ACS was used as a carrier for chitosan, chitosan showed effective osteogenesis in the perforated defective region of the Sprague-Dawley rat's calvarial bone.

• Journal of Periodontal and Implant Science
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• v.31 no.1
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• pp.1-23
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• 2001

Chitosan is biodegradable natural polymer that has been demonstrated its ability to improve wound healing, and calcium metaphosphate(CMP) is a unique class of phosphate minerals having a polymeric structure. In this study, chitosan/CMP and platelet derived growth factor(PDGF-BB) loaded chitosan/CMP sponges were developed, and the effect of the sponges on bone regeneration and their possibility as scaffolds for bone formation by three-dimensional osteoblast culture were examined. PDGF-BB loaded chitosan/CMP sponges were prepared by freeze-drying of a mixture of chitosan solution and CMP powder, and soaking in a PDGF-BB solution. Fabricated sponge retained its 3-dimensional porous structure with $100-200\;{\mu}m$ pores. The release kinetics of PDGF-BB loaded onto the sponge were measured in vitro with $^{125}I-labeled$ PDGF-BB. In order to examine their possibility as scaffolds for bone formation, fetal rat calvarial osteoblastic cells were isolated, cultured, and seeded into the sponges. The cell-sponge constructs were cultured for 28 days. Cell proliferation, alkaline phosphatase activity were measured at 1, 7, 14 and 28 days, and histologic examination was performed. In order to examine the effect on the healing of bone defect, the sponges were implanted into rat calvarial defects. Rats were sacrificed 2 and 4 weeks after implantation and histologic and histomorphometrical examination were performed. An effective therapeutic concentration of PDGF-BB following a high initial burst release was maintained throughout the examination period. PDGF-BB loaded chitosan/CMP sponges supported the proliferation of seeded osteoblastic cells as well as their differentiation as indicated by high alkaline phosphatase activities. Histologic findings indicated that seeded osteoblastic cells well attached to sponge matrices and proliferated in a multi-layer fashion. In the experiments of implantation in rat calvarial defects, histologic and histomorphometric examination revealed that chitosan/CMP sponge promoted osseous healing as compared to controls. PDGF-BB loaded chitosan/CMP sponge further echanced bone regeneration. These results suggested that PDGF-BB loaded chitosan/CMP sponge was a feasable scaffolding material to grow osteoblast in a three-dimentional structure for transplantation into a site for bone regeneration.

• Journal of Periodontal and Implant Science
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• v.36 no.3
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• pp.745-755
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• 2006

The purpose of this study was to investigate the effects of irradiated frozen allogenic bone(IFAB) on the cell proliferation and differentiation of human fetal osteoblasts. Human fetal osteoblasts(hFOB1) were cultured to examine the cellular proliferation for 3 days and 5 days with $1mg/m{\ell}$, $100{\mu}g/m{\ell}$, $10{\mu}g/m{\ell}$, $1{\mu}g/m{\ell}$, $100ng/m{\ell}$, $10ng/m{\ell}$, $1ng/m{\ell}$ of IFAB, and to compare the ALP synthesis to control groups for 3 days with DMEM/F-12 1:1 Mixture and $1mg/m{\ell}$, $100{\mu}g/m{\ell}$, $10{\mu}g/m{\ell}$, $1{\mu}g/m{\ell}$, $100ng/m{\ell}$, $10ng/m{\ell}$, $1ng/m{\ell}$ of IFAB. To compare the calcium accumulation, hFOBl cultured for 23 days were quantified and photographed. The cellular proliferation of hFOBls treated with IFAB was increased at 5 days to control(p<0.05). The activity of ALP in hFOBls treated with $100ng/m{\ell}$ IFAB was significantly increased at 5 days(p<0.05). A quantified calcium accumulation in hFOBl was significantly increased at $100ng/m{\ell}$, $10ng/m{\ell}$ of IFAB(p<0.05). In the present study, we found that IFAB playa important role of bone formation in the early stage. There was considered that IFAB could be used in the bone graft material.

• Journal of Dental Rehabilitation and Applied Science
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• v.29 no.2
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• pp.141-151
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• 2013

The nano-surface modification techniques could be classified; internal modifications which enhance surface roughness and porosity in nano level and external modifications as nano particle coating. Nano-modified implant surface has various morphograpies such as nanotube, nanopit, nanonodule and polymorphic structures. Creating surface depends upon preparation method and material, however, there is no standard preparation technique not yet. The nano-modified surfacet is electrochemically stable comparing with the surface modified in micron level. Nano-modified surface has little cytotoxicity, stimulates osteoblast proliferation and differentiation. Moreover, it decreases soft tissue intervention by interrupting the proliferation of fibroblast. Nanostructure has similar size and shape with cells and proteins, consequently leads to good biocompatibility and enhanced osseointegration. However, the actual effect in vivo is limited, due to the distance of effect. Even if nano-modified surface has antibiotic property due to photocatalysis, short duration time makes clinical application questionable. Further investigations should focus on the optimal nano-modified surface, which has many potentials.

• Journal of Life Science
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• v.21 no.2
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• pp.300-308
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• 2011

Osteoporosis is a disease involving a decrease in bone mineral density and increased risk of fractures. Osteoblast and osteoclast activities are important for bone formation. The MC3T3-E1 osteoblastic cell line is a well-accepted model of osteogellsis in vitro. Hijikia fusiforme is a kind of edible brown seaweed that grows mainly in the Northwest Pacific region, including the countries of Korea, Japan and China, and it has been widely used as a medicinal and health food in Korea. In this study, by using osteoblasts, the effects of Hijikia fusiforme fractions on proliferation, alkaline phosphatase (ALP) activity, collagen synthesis and mineralization of cells were investigated. Hijikia fusiforme were subjected to fractionation by using hexane, methanol, butanol and aqueous. Proliferation of the MC3T3-E1 osteoblastic cells that were treated with Hijikia fusiforme fractions increased by approximately 120%. Regarding effects of Hijikia fusiforme fractions on ALP activity, 1 ${\mu}g$/ml butanol fraction showed the highest activity. The synthesis of collagen increased significantly in response to treatment with Hijikia fusiforme fractions, with the exception of the hexane fraction. Moreover, mineralization in the MC3T3-E1 cells that were treated with 100 ${\mu}g$/ml butanol fraction increased by 281%. Also, when 100 ${\mu}g$/ml aqueous fraction was added, mineralization increased by 240%. These results indicate that Hijikia fusiforme fractions have anabolic effect on bone through the promotion of osteoblastic differentiation, suggesting that it could be used for the treatment of common metabolic bone diseases.

• Journal of Life Science
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• v.21 no.12
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• pp.1752-1760
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• 2011

In this study, the effect of the Opuntiahumifusa extracts on proliferation, alkaline phosphatase (ALP) activity, collagen synthesis and ROS level of a cell was investigated using an osteoblast. Opuntiahumifusawas separated intoOpuntiahumifusapeel (OH-P), seed (OH-Se) and stem (OH-St).These were subjected to extraction by using hot water and ethanol. The proliferation of the MC3T3-E1 osteoblastic cells that were treated with OH-Se water extract were increased by approximately 120%. Regarding the effects of OH-Se on ALP activity, the $50{\mu}g/ml$ ethanol extract group showed the highest activity. The synthesis of collagen increased significantly in response to treatment with OH-Se water extract. The ROS scavenging effects of Opuntiahumifusawere investigated for involvement of oxidativedamage, cell culture and staining. Also, when OH-Se water extract $100{\mu}g/ml$ was added, the ROS level decreased by 54%. These results indicate that Opuntiahumifusa extracts have an anabolic effect on bone through the promotion of osteoblastic differentiation, suggesting that it could be used for the treatment of common metabolic bone diseases.

• Journal of Periodontal and Implant Science
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• v.26 no.2
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• pp.448-468
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• 1996

To maintain its functional integrity, bone is continuously remodelled by a process involving resorption by osteoeclasts and formation by osteoblasts, In order to respond to changes in the physical environment or to trauma with the relevant action, this process is strictly regulated by locally synthesized or systemic fators, Prostaglandin $E_2(PGE_2$) is perhaps one of the best studied factors, having been known to affect bone cell function for several decades.$PGE_2$ has both anabolic and catabolic activities. Excess of $PGE_2$ has been implicated in a number of pathological states associated with bone loss in a number of chronic inflammatory conditions such as periodontal disease and rheumatoid arthritis. $PGE_2$ and other arachidonic acid metabolites have been shown to be potent stimulators of osteoclastic bone resorption in organ culture. The anabolic effects of $PGE_2$ were first noticed when an increase in periosteal woven bone formation was seen after the infusion of $PGE_2$ into infants in order to prevent closure of the ductus arteriosus. The cellular basis for the catabolic actions of $PGE_2$ has been well characterized. $PGE_2$increases osteoclast recruitment in bone marrow cell cultures. Also $PGE_2$ has a direct action on osteoclast serving to inhibit activity and can also indirectly activate osteoclast via other cells in the vicinity, presumably osteoblast. The cellular mechanisms for the anabolic actions of $PGE_2$ are not nearly so well understood. The purpose of this paper was to study the effects of $PGE_2$ and dibutyl(DB)cAMP on osteoblastic clone MC3T3El cells and on the generation of osteoclasts from their precursor cells. The effect of $PGE_2$ and DBcAMP on the induction of alkaline phoaphatase(AlP) was investigated in osteoblastic clone MC3T3El cells cultured in medium containing 0.4% fetal bovine serum. $PGE_2$ and DBcAMP stimulated ALP activity and MTT assay in the cells in a dose-dependent manner at concentrations of lO-SOOng/ml. Cycloheximide, protein synthesis inhibitor, inhibited the stimulative effect of $PGE_2$ and DBcAMP on ALP activity in the cells. $PGE_2$also increased the intracellular cAMP content in a dose-dependent fashion with a maximal effect at 500ng/ml. The effect of $PGE_2$ on the generation of osteoclasts was investigated in a coculture system of mouse bone marrow cells with primary osteoblastic cells cultured in media containing 10% fetal bovine serum.After cultures, staining for tartrate-resistant acid phosphatase(TRAP)-marker enzyme of osteoclast was performed. The TRAP(+) multinucleated cells(MNCs), which have 3 or more nuclei, were counted. More TRAP(+) MNCs were formed in coculture system than in control group. $PGE_2(10^{-5}10^{-6}M)$ stimulated the formation of osteoclast cells from mouse bone marrow cells in culture. $PGE_2(10^{-6}M)$ stimulated the formation of osteoclast cells from mouse bone marrow cells in coculture of osteoblastic clone MC3T3E1 cells This results suggest that $PGE_2$ stimulates the differentiation of osteoblasts and generation of osteoclast, and are involved in bone formation, as well as in bone resorption.