• International Journal of Oral Biology
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• 제35권3호
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• pp.99-106
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• 2010

Luteolin is a flavonoid that exists in a glycosylated form in celery and green pepper. Flavonoids possess antioxidant and anti-inflammatory properties and can reduce the expression of key inflammatory molecules in macrophages and monocytes. It has been reported also that some flavonoids have effects on bone metabolism. The effects of luteolin on the function of osteoblasts were investigated by measuring cell viability, alkaline phosphatase activity, type I collagen production, osteoprotegerin secretion, Wnt promoter activity, BMP-2 and Runx2 expression and calcified nodule formation. Luteolin has no effects upon osteoblast viability but induced an increase in alkaline phosphatase activity, type I collagen production and a decrease in osteoprotegerin secretion in these cells. Luteolin treatment also upregulated BMP-2 mRNA expression. These results suggest that luteolin may be a regulatory molecule that facilitates the differentiation of osteoblasts.

• 대한예방한의학회지
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• 제12권2호
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• pp.197-206
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• 2008

The inhibition of osteoblast by glucocorticoid is recognized as its action mechanism of decreased bone formation. In this study, the effect of JY, Jahyulyangkeuntang, on the differentiation and mineralization of osteoblastic cells was investigated in the presence of dexamethasone. The cell counting, enzyme activity assay, MTT assay, collagen content assay were done to determine the cell proliferation, alkaline phosphatase(ALP) activity, bone martrix production, and cell apoptosis. JY enhanced the cell proliferation after the culture for 10 days. ALP activity and total protein synthesis, and intracellular collagen synthesis were increased when the cells were treated with JY. And JY restored calvarial cell function decreased by dexamethasone.

• Journal of Periodontal and Implant Science
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• 제50권5호
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• pp.291-302
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• 2020

Purpose: The objective of this study was to investigate whether phelligridin D could reduce glucose-induced oxidative stress, attenuate the resulting inflammatory response, and restore the function of human periodontal ligament cells (HPDLCs). Methods: Primary HPDLCs were isolated from healthy human teeth and cultured. To investigate the effect of phelligridin D on glucose-induced oxidative stress, HPDLCs were treated with phelligridin D, various concentrations of glucose, and glucose oxidase. Glucose-induced oxidative stress, inflammatory molecules, osteoblast differentiation, and mineralization of the HPDLCs were measured by hydrogen peroxide (H₂O₂) generation, cellular viability, alkaline phosphatase (ALP) activity, alizarin red staining, and western blot analyses. Results: Glucose-induced oxidative stress led to increased production of H₂O₂, with negative impacts on cellular viability, ALP activity, and calcium deposition in HPDLCs. Furthermore, HPDLCs under glucose-induced oxidative stress showed induction of inflammatory molecules (intercellular adhesion molecule-1, vascular cell adhesion protein-1, tumor necrosis factor-alpha, interleukin-1-beta) and disturbances of osteogenic differentiation (bone morphogenetic protein-2, and -7, runt-related transcription factor-2), cementogenesis (cementum protein-1), and autophagy-related molecules (autophagy related 5, light chain 3 I/II, beclin-1). Phelligridin D restored all these molecules and maintained the function of HPDLCs even under glucose-induced oxidative stress. Conclusions: This study suggests that phelligridin D reduces the inflammation that results from glucose-induced oxidative stress and restores the function of HPDLCs (e.g., osteoblast differentiation) by upregulating autophagy.

• International Journal of Oral Biology
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• 제31권2호
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• pp.53-65
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• 2006

Calcium concentration in the bone resorption lacunae is high and is in the mM concentration range. Both osteoblast and osteoclast have calcium sensing receptor in the cell surface, suggesting the regulatory role of high extracellular calcium in bone metabolism. In vitro, high extracellular calcium stimulated osteoclastogenesis in coculture of mouse osteoblasts and bone marrow cells. Therefore we examined the genes that were commonly regulated by both high extracellular calcium and $1,25(OH)_2vitaminD_3(VD3)$ by using mouse oligo 11 K gene chip. In the presence of 10 mM $[Ca^{2+}]e$ or 10 nM VD3, mouse calvarial osteoblasts and bone marrow cells were co-cultured for 4 days when tartrate resistant acid phosphatase-positive multinucleated cells start to appear. Of 11,000 genes examined, the genes commonly regulated both by high extracellular calcium and by VD3 were as follows; 1) the expression of genes which were osteoclast differentiation markers or were associated with osteoclastogenesis were up-regulated both by high extracellular calcium and by VD3; trap, mmp9, car2, ctsk, ckb, atp6b2, tm7sf4, rab7, 2) several chemokine and chemokine receptor genes such as sdf1, scya2, scyb5, scya6, scya8, scya9, and ccr1 were up-regulated both by high extracellular calcium and by VD3, 3) the genes such as mmp1b, mmp3 and c3 which possibly stimulate bone resorption by osteoclast, were commonly up-regulated, 4) the gene such as c1q and msr2 which were related with macrophage function, were commonly down-regulated, 5) the genes which possibly stimulate osteoblast differentiation and/or mineralization of extracellular matrix, were commonly down-regulated; slc8a1, admr, plod2, lox, fosb, 6) the genes which possibly suppress osteoblast differentiation and/or mineralization of extracellular matrix, were commonly up-regulated; s100a4, npr3, mme, 7) the genes such as calponin 1 and tgfbi which possibly suppress osteoblast differentiation and/or mineralization of extracellular matrix, were up-regulated by high extracellular calcium but were down-regulated by VD3. These results suggest that in coculture condition, both high extracellular calcium and VD3 commonly induce osteoclastogenesis but suppress osteoblast differentiation/mineralization by regulating the expression of related genes.

• Journal of Periodontal and Implant Science
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• 제32권1호
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• pp.1-12
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• 2002

The periodontal ligament(PDL) is a unique tissue that is crucial for tooth function. However, little is known of the molecular mechanisms controlling PDL function. PDL-specific protein;PDLs22 had been previously identified as a novel protein isolated from cultured human PDL fibroblasts using subtraction hybridization between human gingival fibroblasts and PDL fibroblasts. The aim of this study was to examine the expression pattern and tissue localization of PDLs22 protein in embryonic and various postnatal stages of developing mouse using immunohistochemical staining. Embryos (E18) and postnatal (P1, P4, P5, P15, P18) were decapitated and the heads were fixed overnight in a freshly prepared solution of 4% paraformaldehyde. Some specimens were decalcified for $2{\sim}4$ weeks in a solution containing 10% of the disodium salt of ethylenediamine-tetraacetic acid (EDTA). Next, tissues were dehydrated, embedded in paraffin and sectioned serially at $6{\mu}m$ in thickness. Polyclonal antiserum raised against PDLs22 peptides, ISNKYLVKRQSRD, were made. The localization of PDLs22 in tissues was detected by polyclonal antibody against PDLs22 by means of immunohistochemical staining. The results were as follows; 1. Expression of PDLs22 protein was not detected in the tooth germ of bud and cap stage. 2. At the late bell stage and root formation stage, strong expression of PDLs22 protein was observed in developing tooth follicle, osteoblast-like cells, and subodontoblastic cells in the tooth pulp, but not in gingival fibroblasts, ameloblasts and odontoblasts of tooth germ 3. In erupted tooth, PDLs22 protein was intensely expressed in PDL and osteoblast-like cells of alveolar bone, but not in gingival fibroblasts, mature osteocytes and adjacent salivary glands. 4. In the developing alveolar bone and mid-palatal suture, expression of PDLs22 protein was seen in undifferentiated mesenchymal cells and osteoblast-like cells of developing mid-palatal suture, but not in mature osteocytes and chondrocytes. These results suggest that PDLs22 protein may play an important role in the differentiation of undifferentiated mesenchymal cells in the bone marrow and PDL cells, which can differentiate into multiple cell types including osteoblasts, cementoblasts, and PDL fibroblasts. However, more researches should be performed to gain a better understanding of the exact function of PDLs22 protein which related to the PDL cell differentiation.

• 한국식품과학회지
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• 제44권1호
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• pp.82-88
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• 2012

감국 에탄올 추출물이 $H_2O_2$로 유도한 산화적 스트레스 상황에서 MC3T3-E1 조골세포의 증식 및 분화, ROS 생성 및 염증 매개성 cytokine인 TNF-${\alpha}$ 생성 등에 미치는 영향을 분석하였다. $H_2O_2$로 유도한 산화적 스트레스 상황에서 감국 에탄올 추출물은 30-100 ${\mu}g/mL$ 농도 범위에서 조골세포의 증식을 유의적으로 증가시켰다. 또한, 감국 에탄올 추출물 200 ${\mu}g/mL$ 농도에서 ALP 활성이 약 1.5배 유의적인 증가를 나타냈다. 그러나 collagen 합성에는 유의적 차이를 보이지 않았다. Mineralization 측정에서는 200 ${\mu}g/mL$ 농도에서 대조군에 비해 유의적 증가를 보였다. $H_2O_2$로 유도한 산화적 스트레스 상황에서 감국 에탄올 추출물이 intracellular ROS 생성에 미치는 영향을 측정해본 결과, 30 ${\mu}g/mL$ 농도에서 antioxidant인 trolox 20 ${\mu}M$과 유사한 ROS 생성수준을 나타내어 유사한 항산화 효과를 보였으며, 그 이상의 농도에서는 더 높은 항산화 효과를 나타냈다. $H_2O_2$로 유도한 산화적 스트레스 상황에서 조골세포의 collagen 및 ALP의 합성을 억제하고 파골세포로의 분화 증강과 골흡수를 촉진시키는 것으로 알려진 TNF-${\alpha}$ 생성정도를 측정한 결과, 감국 에탄올 추출물 처리에 의해 농도 의존적으로 생성이 감소되었으며, 200 ${\mu}g/mL$ 농도에서 대조군 대비 89% 수준을 나타내어 유의적 차이를 보였다. 이상의 결과를 통해 감국 에탄올 추출물은 $H_2O_2$로 유도된 산화적 스트레스 상황에서 세포 내 ROS 생성과 염증매개 cytokine인 TNF-${\alpha}$ 생성을 감소시킴으로써 조골세포 손상과 활성 감소를 억제하고, 증식과 분화를 촉진시키는 효과가 있는 것을 확인할 수 있었다. 따라서 감국 에탄올 추출물의 골다공증 예방을 위한 식물성 에스트로젠(phytoestrogen) 및 항산화 소재로의 이용 가능성이 있을 것으로 사료된다.

• 구강회복응용과학지
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• 제20권1호
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• pp.31-41
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• 2004

The osseointegration in implant therapy is achieved following general wound healing mechanism. Platelet play a major role in wound healing process. In addition to blood clot formation, they secrete many growth factors which regulate the attachment, proliferation and differentiation of nearly all cell types. The use of these growth factors is now known to be very effective methods to improve the cellular activity. Platelet-rich plasma which is made with the newly developed technique concentrating platelets 3-folds or more is also proven to be very effective method to stimulate and accelerate the healing of bone and soft tissue. Previous study proved that platelet-rich plasma enhanced the cellular attachment by inducing fibronectin, vitronectin from osteoblast. So, this study was aimed to investigate the effect of platelet-rich plasma on the cellular proliferation and differentiation in vitro. The effect on the proliferation was evaluated by MTT assay. To evaluate autocrine and paracrine effect, conditioned medium was made and compared. By measuring alkaline phosphatase activity, the effect on the cellular differentiation was evaluated. The results were as following: The cellular proliferation of osteoblast cell line increased depending on the concentration of platelet-rich plasma and conditioned medium. The alkaline phosphatase activity increased depending on the concentration of platelet-rich plasma and conditioned medium. These findings imply that platelet-rich plasma enhance the cellular proliferation and differentiation and maximize the cellular activity by using the autocrine and paracrine effect.

• Journal of Nutrition and Health
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• 제51권4호
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• pp.316-322
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• 2018

Purpose: The Glycyrrhiza uralensis species (Leguminosae) as a medicinal biocompound, and one of its root components, isoliquritigenin (ISL), which is a flavonoid, has been reported to have anti-tumor activity in vitro and in vivo. However, its function in bone formation has not been studied yet. In this study, we tested the effect of Glycyrrhiza uralensis (ErLR) and baked Glycyrrhiza uralensis (EdLR) extracts on osteoblast proliferation, alkaline phosphatase (ALP) activity, and bone-related gene expression in osteoblastic MC3T3-E1 cells. Methods: MC3T3-E1 cells were cultured in various levels of ErLR (0, 5, 10, 15, $20{\mu}g/mL$), EdLR (0, 5, 10, 15, $20{\mu}g/mL$), or ISL (0, 5, 10, 15, $20{\mu}M$) in time sequences (1, 5, and 20 days). Also, isoliquritigenin (ISL) was tested for comparison to those two biocompound extracts. Results: MTT assay results showed that all three compounds (ErLR, EdLR, and ISL) increased osteoblastic-cell proliferation in a concentration-dependent manner for one day. In addition, both ErLR and EdLR compounds elevated the osteoblast proliferation for 5 or 20 days. Extracellular ALP activity was also increased as ErLR, EdLR, and ISL concentration increased at 20 days, which implies the positive effect of Glycyrrhiza species on osteoblast mineralization. The bone-related marker mRNAs were upregulated in the ErLR-treated osteoblastic MC3T3-E1 cells for 20 days. Bone-specific transcription factor Runx2 gene expression was also elevated in the ErLR- and EdLR-treated osteoblastic MC3T3-E1 cells for 20 days. Conclusion: These results demonstrated that Glycyrrhiza uralensis extracts may be useful for preventing osteoporosis by increasing cell proliferation, ALP activity, and bone-marker gene expression in osteoblastic cells.

• BMB Reports
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• 제50권2호
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• pp.97-102
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• 2017

Patients with inflammatory bone disease or cancer exhibit an increased risk of fractures and delayed bone healing. The S100A4 protein is a member of the calcium-binding S100 protein family, which is abundantly expressed in inflammatory diseases and cancers. We investigated the effects of extracellular S100A4 on osteoblasts, which are cells responsible for bone formation. Treating primary calvarial osteoblasts with recombinant S100A4 resulted in matrix mineralization reductions. The expression of osteoblast marker genes including osteocalcin and osterix was also suppressed. Interestingly, S100A4 stimulated the nuclear factor-kappaB (NF-${\kappa}B$) signaling pathway in osteoblasts. More importantly, the ex vivo organ culture of mouse calvariae with recombinant S100A4 decreased the expression levels of osteocalcin, supporting the results of our in vitro experiments. This suggests that extracellular S100A4 is important for the regulation of bone formation by activating the NF-${\kappa}B$ signaling pathway in osteoblasts.

• Biomolecules & Therapeutics
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• 제8권2호
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• pp.179-183
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• 2000

To determine biosafety of fluorosilicic acid as a source of fluoride, we carried out acute toxicity and general pharmacological studies using mouse. Fluorosilicic acid had little effects on general behavior, pain response, convulsion, skeletal muscle function and intestinal mobility as compared to controls. It had either little adverse effects on alkaline phosphatase and collagen levels in osteoblast cells. This study supports the safety of fluorosilicic acid in animals.