• Archives of Pharmacal Research
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• 제27권12호
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• pp.1258-1262
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• 2004

Phosphodiesterase (PDE) 4 is an enzyme that degrades intracellular cAMP. In the present study, the effect of rolipram, a specific phosphodiesterase (PDE) 4 inhibitor, on osteoclast formation was investigated. Rolipram induced osteoclast formation in cocultures of mouse bone marrow cells and calvarial osteoblasts. This activity was not observed in the absence of calvarial osteoblasts, suggesting that calvarial osteoblasts are likely target cells of rolipram. Osteoclast formation by rolipram was completely blocked by the addition of osteoprotegerin (OPG), a soluble decoy receptor for the osteoclast differentiation factor, TNF-related activation-induced cytokine (TRANCE, identical to RANKL, ODF, and OPGL). Northern blot analysis revealed the effect of rolipram to be associated with the increased expression of TRANCE mRNA in mouse calvarial osteoblasts. Collectively, these data indicate that PDE4 inhibitor up-regulates the TRANCE mRNA expression in osteoblasts, which in turn controls osteoclast formation.

• 약학회지
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• 제49권1호
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• pp.109-113
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• 2005

In the present study treatment of IBMX, a phosphodiesterase (PDE) inhibitor, alone induced osteoclast formation in co-cultures of mouse bone marrow cells and calvarial osteoblasts. However, treatment of IBMX in combination with prostaglandin $E_2\;(PGE_2)$ inhibited osteoclast formation in a dose-dependent manner. Among various isozyme-specific PDE inhibitors, a PDE4 specific inhibitor, rolipram, showed similar effects as IBMX on osteoclast formation. To address the involvement of cyclic adenosine monophosphate (cAMP) in osteoclast formation, cAMP concentration in calvarial osteoblasts was investigated. When calvarial osteoblasts were co-cultured with IBMX alone or in combination with $PGE_2$, the patterns of cAMP concentration in calvarial osteoblasts were differ each other suggesting that cAMP in calvarial osteoblasts subtly regulates osteoclast formation.

• 약학회지
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• 제48권3호
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• pp.197-201
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• 2004

Phosphodiesterases (PDEs) are enzymes that degrade intracellular cAMP. In the present study, pentoxifylline, a PDE inhibitor, induced osteoclast formation in co-cultures of mouse bone marrow cells and calvarial osteoblasts. To address the involvement of the osteoclast differentiation factor TNF-related activation-induced cytokine (TRANCE, identical to RANKL, ODF, and OPGL), mouse bone marrow cells and calvarial osteoblasts were co-cultured with pentoxifylline in the presence of OPG, a decoy receptor for TRANCE. The osteoclastogenic effect of pentoxifylline was completely blocked by addition of OPG, suggesting that TRANCE is involved in the osteoclast formation induced by pentoxifylline, Northern blot analysis revealed that pentoxifylline significantly induced TRANCE mRNA expression in calvarial osteoblasts. These results suggests that pentoxifylline regulates TRANCE expression in osteoblasts, which in turn controls osteoclast formation.

• BMB Reports
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• 제45권10호
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• pp.571-576
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• 2012

Radiotherapy is considered to cause detrimental effects on bone tissue eventually increasing bone loss and fracture risk. However, there is a great controversy on the real effects of irradiation itself on osteoblasts, and the mechanisms by which irradiation affects osteoblast differentiation and mineralization are not completely understood. We explored how X-ray radiation influences differentiation and bone-specific gene expression in mouse calvarial osteoblasts. Irradiation at 2 Gy not only increased differentiation and mineralization of the cells, but also upregulated the expression of alkaline phosphatase, type I collagen, osteopontin, and osteocalcin at early stages of differentiation. However, irradiation at higher doses (>2 Gy) did not stimulate osteoblast differentiation, rather it suppressed DNA synthesis by the cells without a toxic effect. Additional experiments suggested that transforming growth factor-beta 1 and runt-transcription factor 2 play important roles in irradiation- stimulated bone differentiation by acting as upstream regulators of bone-specific markers.

• 대한한의학회지
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• 제25권4호
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• pp.15-25
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• 2004

Objective : We studied the effect of Bambusae concretio Silicea (BCS) on bone metabolism. Methods : At first, we treated PTH, 1,25(OH)₂D₃, mononuclear cell conditioned medium (MCM) and IL-1 to osteoblast cells derived from mouse calvarial bone explants in vitro, and then investigated the activities of collagenolysis and bone resorption factors. Results : BCS extracts have no cytotoxicities in concentrations of 1-150 ㎍/ml. BCS had protective activity against PTH (5 units/ml), MCM (5%, v/v), 1,25(OH)₂D₃ (20 ng/ml), IL-1α(2 ng/ml) and IL-1β, (1 ng/ml)-induced collagenolysis in the mouse calvarial cells. And, pretreatment of BCS for 1 hr significantly reduced the collagenolysis. Furthermore, it was much more expressed at 16 hrs after BCS (50 ㎍/ml)-pretreatment. And, BCS significantly protected against enhanced collagenolysis induced by IL-1α and IL-1β. Conclusion : BCS extracts inhibited the bone resorption in mouse calvarial bone cell;, thus BCS could be used clinically for bone diseases.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제28권2호
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• pp.114-125
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• 2002

This study was designed to evaluate the influence of fibroblasts or connective tissue from mouse oral mucosa on differentiation of neonatal mouse calvaria-derived osteoblasts and mineralization of bone nodules. Primary cell cultures from mouse calvarial osteoblasts and 2-4 passaged fibroblasts from oral mucosa were co-cultured in monolayer cultures, devided into 6 experimental group according to cell density or cell confluency. Osteoblasts were also co-cultured with fibroblasts in $Transwell^{(R)}$ culture plate with different co-cultured period according to osteoblast differentiation. The alkaline phosphatase activity were measured in monolayer cultures and cultures using $Transwell^{(R)}$. The mineralized bone nodules were presented by Von Kossa staining and density of mineralized nodules was measured by image analysis. The connective tissues with or without osteoblast seeding were cultured and examined histologically by Von Kossa and Trichrome Goldner staining. The results were as follows; 1. Prolonged maturation of matrix and delayed mineralization of bone nodules were resulted in monolayer cultures. 2. Co-culture of fibroblast with osteoblast using $Transwell^{(R)}$ during osteoblast proliferation stage stimulated proliferation of osteoblasts and increased alkaline phosphatase activity and mineralization of bone nodules. 3. Co-culture of fibroblast with osteoblast using $Transwell^{(R)}$ during matrix mineralization stage decreased and delayed mineralization of bone nodules. 4. In vitro cultured connective tissue with osteoblast seeding resulted in proliferation of osteoblasts and matrix formation with mineralization.

• 대한한방부인과학회지
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• 제15권4호
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• pp.45-60
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• 2002

생쥐의 calvarial osteoblast세포를 분리배양하여 gelatinase생성여부를 골흡수과정에서의 역할을 규명하기 위하여 SDS-PAGE-zymography분석을 한 결과 progelatinase-A를 항속적으로 합성하고 있음을 확인하였다. 생쥐의 osteoblasts를 골재흡수 약물인 PTH, $1,25(OH)_2D_3$, 단핵구배양액 (MCM) 그리고 IL-1으로 자극시키면 gelatinase생산을 촉진하여 콜라겐분해가 증가되었으나, indomethacin과 dexamethasone은 생쥐의 osteoblastic세포의 collagenolysis를 저해하였다. 한편, 골재흡수에 IL-1을 생쥐태아 유래의 장골조직배양 (fetal mouse long bone organ culture)에 처리하자 IL-1 은 골재흡수를 촉진하였다. 더우기, $IL-1{\alpha}$의 농도의존성에 대한 indomethacin과 dexametasone의 영향을 검토한 결과 직선형의 비례커브로 영향을 미쳤다. 이러한 골대사의 지견을 바탕으로 대영전-자하거의 열수추출물의 시험관내 독성검사에서 $1-200\;{\mu}g/ml$의 농도에서는 독성이 없었으며, 또한, $300\;{\mu}g/ml$ 농도에서도 생쥐의 calvarial골에는 독성이 없었다. 대영전-자하거 extract는 PTH (2 units/ml), MCM (5%, v/v), $rhIL-1{\alpha}$ (1 ng/ml) $1,25(OH)_2D_3$ (10 ng/ml)처리에 대해서 그리고 $IL-1{\alpha}$와 $IL-1{\beta}$-유발 collagenolysis에 대해서도 보호효과가 있었다. 대영전-자하거extract을 1시간동안 전처리와 후처리에서 콜라겐분해에 약간의 보호활성이 있었으며 $IL-1{\alpha}$와 $IL-1{\beta}$에 의해 유발되는 콜라겐분해에 보호활성이 보였다. 1시간동안 전처리는 콜라겐분해를 감소시키며, 대영전-자하거 extract는 gelatinase효소를 저해하였으며 PTH, $1,25(OH)_2D_3$, $IL-1{\beta}$ 및 $IL-1{\alpha}$로 유발된 효소활성화가 저해되었다. 즉, 대영전-자하거 extracts는 $IL-1{\alpha}-$와 $IL-1{\beta}$에 의해 촉진되는 골재흡수에 효과적이었으며, 비스테로이드성 항염증제제 (indomethacin 과 dexamethasone)에 의한 골재흡수방지 효과와 유사하였다. 이러한 결과는 대영전-자하거extract가 골다공증치료에 효과적임을 나타내는 것이다.

• 동국한의학연구소논문집
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• 제9권
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• pp.179-191
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• 2000

한방에서 건강골(建强骨)시키는 효능이 있는 5가지 약물(골쇄보(骨碎補), 상기생(桑寄生), 김모구척(金毛狗脊), 별갑(別甲), 법파고지(法破古紙))로 구성된 처방(CEDR로 약칭)으로 실험을 하였다. 생쥐의 calvarial osteoblast를 분리하고 배양한 후 실험을 행하였는데, 골 재흡수 인자인 PTH, $1,25(OH)_2D_3$, $TNF-\alpha$, IL-1에 자극받은 osteoblasts는 활동적인 gelatinase를 생산하므로서 collagen 용해를 증가시켰다. 암컷 생쥐의 long bone organ을 culture하여 골 재흡수를 자극하는 IL-1를 실험한 결과, IL-1은 골의 재흡수를 자극하였으며 동시에 존재해있을 때에는 뚜렷한 재흡수를 보였다. 더욱이, indomethacin과 dexamethasone이 $IL-1{\alpha}$의 투여량 증가에 대한 영향을 관찰하였을 때에는 indomethacin과 dexamethasone은 IL-1의 투여량에 대한 곡선 그래프를 오른쪽으로 이동시켰다. 시험관내에서 세포 독성에 대하여 관찰하였을 때, CEDR추출물은 $1-60{\mu}g/ml$의 농도에서 아무런 세포 독성이 나타나지 않았으며, 뿐만 아니라 생쥐의 두개골 세포에서는 $120{\mu}g/ml$ 농도에서 전혀 세포독성이 관찰되지 않았다. CEDR 추출물은 생쥐의 calvarial cells에서 PTH (5 units/ml), $IL-1{\alpha}$ (1 ng/ml), $TNF-\alpha$, $1,25(OH)_2D_3$ (20 ng/ml) 및 $IL-1{\alpha}$, $IL-1{\beta}$에 유도되는 collagen 용해를 보호하는 효과가 있었다. CEDR 추출물을 1시간동안 전처리하였을 때, 그 자체로는 세포 생존에 영향이 없었으며, collagen 용해를 증가시키지도 않았으며 전처치로 collagen 용해를 유의성있게 감소시키지도 않았다. 게다가, 추출물은 $IL-1{\alpha}$와 $IL-1{\beta}$에 의해 유도되는 collagen 용해를 방지하는 효과가 있었다. 1시간 동안 전처리로 한 결과, collagen 용해를 유의성있게 감소시켰다. 흥미로운 것은 CEDR 추출물이 gelatinase 활성과 PTH, $1,25(OH)_2D_3$, $TNF-\alpha$, $IL-1{\beta}$ 및 $IL-1{\alpha}$의 재흡수 인자에 유도되어 진행되는 활성을 억제하였으며, CEDR 전처리시에는 강력한 보호 효과를 나타내었다. CEDR 추출물은 $IL-1{\alpha}$와 $IL-1{\beta}$에 자극되는 골 재흡수를 억제하는 효과를 나타내였으며, 또한 농도를 다양하게 한 CEDR의 전처리시에는 유의성이 있었다. Indomethacin과 dexamethasone의 비 스테로이드성 항 염증 인자에 의한 IL-1에 자극받은 골 재흡수를 억제하는 정도와 현상은 CEDR 추출물을 생쥐의 두개골 배양 시스템에 적용시켜 얻은 결과와 유사하였다. 이러한 결과들로 보건데, CEDR 추출물은 임상적으로 골다공증의 치료에 매우 안정적으로 적용할 수 있음을 제시하고 있다.

• Journal of Acupuncture Research
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• 제21권4호
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• pp.225-236
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• 2004

본 실험에서는 녹용 약침액의 항 골재흡수 속성을 조사하였다. PTH, $1,25(OH)_2D_3$와 IL-1을 각각 골재흡수 인자로 사용하여 생쥐의 두개골에서 osteoblast 세포를 격리, 배양, 그리고 자극시켰을 때 collagenolysis의 증가를 보였다. 두 가지를 동시에 사용한 결과, IL-1은 골재흡수성을 촉진시키고 재 흡수력을 생산하였다. In vitro에서의 세포독성 결과는 $1-200{\mu}g/ml$의 녹용 약침액 농도 분포에서 무세포독성을 보였다. 또한 녹용 약침액은 생쥐의 두개골 골아세포 내에서 PTH (2 unit/ml), IL-$1{\alpha}$ (1 ng/ml), $1,25(OH)_2D_3$ (10 ng/ml), IL-$1{\alpha}$ 및 IL-$1{\beta}$로 인해 유발된 collagenolysis에 대해서 대항하는 보호활동성을 나타내었다. 녹용약침액은 IL-$1{\alpha}$ 와 IL-$1{\beta}$로 인해 유발된 collagenolysis에 대항하는 보호활동성을 지녔다. DAS는 IL-$1{\alpha}$와 IL-$1{\beta}$로 인해 촉진된 골재 흡수력을 억제하는 효과를 보였다. 이와 같은 결과는 녹용약침액이 골다공증과 연관된 질환에 대해서 매우 안정적인 임상적 사용이 가능한 것을 관찰할 수 있으므로 추후 이와 관련한 지속적인 연구가 필요할 것으로 사료되었다.

• 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.