• Biomolecules & Therapeutics
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• v.18 no.1
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• pp.16-23
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• 2010

Adipocyte differentiation in human bone marrow mesenchymal stem cells (hBM-MSCs) is not as efficient as that in murine pre-adipocytes when induced by adipogenic agents including insulin, dexamethasone, and 3-isobutyl-1-methylxanthine (IDX condition). Therefore, the promotion of adipocyte differentiation in hBM-MSCs has been used as a cell culture model to evaluate insulin sensitivity for anti-diabetic drugs. In hBM-MSCs, $PPAR{\gamma}$ agonists or sulfonylurea anti-diabetic drugs have been added to IDX conditions to promote adipocyte differentiation. Here we show that troglitazone, a peroxisome proliferator-activated receptor-gamma ($PPAR{\gamma}$) agonist, significantly reduced the levels of anti-adipogenic $PGE_2$ in IDX-conditioned hBM-MSC culture supernatants when compared to $PGE_2$ levels in the absence of $PPAR{\gamma}$ agonist. However, there was no difference in the mRNA levels of cyclooxygenases (COXs) and the activities of COXs and prostaglandin synthases during adipocyte differentiation in hBM-MSCs with or without troglitazone. In hBM-MSCs, troglitazone significantly increased the mRNA level of 15-hydroxyprostaglandin dehydrogenase (HPGD) which can act to decrease $PGE_2$ levels in culture. These results suggest that the role of $PPAR{\gamma}$ activation in promoting adipocyte differentiation in hBM-MSCs is to reduce anti-adipogenic $PGE_2$ levels through the up-regulation of HPGD expression.

• Biomolecules & Therapeutics
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• v.20 no.6
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• pp.520-525
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• 2012

Prostaglandin (PG) $E_2$, the most abundant prostaglandin in the human body, is synthesized from arachidonic acid via the actions of cyclooxygenase (COX) enzymes. $PGE_2$ exerts homeostatic, cytoprotective, inflammatory, and in some cases anti-inflammatory effects. Also, it has been reported that $PGE_2$ is involved in hair growth. Diphlorethohydroxycarmalol (DPHC) is a phlorotannin compound isolated from the brown algae Ishige okamurae, with various biological activities in vitro and in vivo. In this study, the biological effect and mechanism of action of DPHC on prostaglandin synthesis in HaCaT human keratinocytes was examined. The results showed that, in these cells, DPHC significantly and dose-dependently induced $PGE_2$ synthesis by increasing the protein and mRNA levels of COX-1 and COX-2. Interestingly, DPHC-induced COX-1 expression preceded that of COX-2. Also, while both rofecoxib and indomethacin inhibited $PGE_2$ production, the latter was seems to be the more potent. From above results, we can expect that DPHC has some beneficial effects via increasing of $PGE_2$ production.

• BMB Reports
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• v.47 no.1
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• pp.45-50
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• 2014

Aspirin has been demonstrated to be effective in inhibiting COX-2 and $PGE_2$ in Alveolar macrophages (AMs). However, the mechanisms have not been fully understood. In the present study, we found that pretreatment with aspirin inhibited LPS-induced COX-2 and$PGE_2$ upregulation, $I{\kappa}B{\alpha}$ degradation, NF-${\kappa}B$ activation and the increase of PKC activity, but elevated LPS-induced the decrease of PTP activity. The PKC inhibitor calphostin C dramatically reduced the COX-2 mRNA and $PGE_2$ levels, but the PTP inhibitor peroxovanadium (POV) significantly increased the COX-2 mRNA and$PGE_2$ levels. Furthermore, the PTP inhibitor mitigated the inhibitory effect of aspirin on COX-2 and$PGE_2$ upregulation and NF-${\kappa}B$ activation, whereas the PKC inhibitor enhanced the inhibitory effects of aspirin on the production of COX-2 and$PGE_2$. Our data indicate a novel mechanism by which aspirin acts as a potent anti-inflammatory agent in alveolus macrophages and ALI.

• Journal of dental hygiene science
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• v.15 no.6
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• pp.753-760
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• 2015

Although nuclear factor of activated T cell (NFAT) plays a key role in inflammation, its anti-inflammatory effects and mechanism of action in periodontitis are still unknown. This study aimed to identify the effects of NFAT on the proinflammatory mediators activated by lipopolysaccharide (LPS) plus nicotine stimulation in human periodontal ligament cells (hPDLCs). The production of nitric oxide (NO) and prostaglandin $E_2(PGE_2)$ was evaluated using Griess reagent and an enzyme immunoassay, respectively. The expression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2) and NFAT proteins was evaluated by Western blot analysis. LPS plus nicotine synergistically induced the production of NO and $PGE_2$ and increased the protein expression of iNOS, COX-2 and NFAT. Treatment with an NFAT inhibitor blocked the LPS plus nicotine-stimulated NO and $PGE_2$ release as well as the expression of iNOS and COX-2. Our data suggest that the LPS plus nicotine-induced inflammatory effects on hPDLCs may act through a novel mechanism involving the action of NFAT. Thus, NFAT may provide a potential therapeutic target for the treatment of periodontal disease associated with smoking and dental plaque.

• International Journal of Oral Biology
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• v.42 no.4
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• pp.149-153
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• 2017

Cyclooxygenase-2 (COX-2)-mediated prostaglandin $E_2$ ($PGE_2$) plays a key role in development and progression of inflammatory responses and Porphyromonas gingivalis is a common endodontic pathogen. In this study, we investigated induction of COX-2 and $PGE_2$ by P. gingivalis in human dental pulp cells (HDPCs). P. gingivalis increased expression of COX-2, but not that of COX-1. Increased levels of $PGE_2$ were released from P. gingivalis-infected HDPCs and this $PGE_2$ increase was blocked by celecoxib, a selective COX-2 inhibitor. P. gingivalis activated all three types of mitogen-activated protein kinases (MAPKs). P. gingivalis-induced activation of nuclear $factor-{\kappa}B$ ($NF-{\kappa}B$) was demonstrated by the results of phosphorylation of $NF-{\kappa}B$ p65 and degradation of inhibitor of ${\kappa}B-{\alpha}$ ($I{\kappa}B-{\alpha}$). Pharmacological inhibition of each of the three types of MAPKs and $NF-{\kappa}B$ substantially attenuated P. gingivalis-induced $PGE_2$ production. These results suggest that P. gingivalis should promote endodontic inflammation by stimulating dental pulp cells to produce $PGE_2$.

• Journal of Physiology & Pathology in Korean Medicine
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• v.19 no.3
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• pp.785-791
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• 2005

Corydalis Tuber has traditionally been used for the treatment of water retention in the body. Administration of the aqueous extract of Corydalis Tuber has been known to be effective for the control of pain and treatment of arthritis. It was reported that Corydalis Tuber possesses anti-inflammatory activity and modulates the intestinal immune system. The effect of Corydalis Tuber against LPS-stimulated expressions of COX-2, iNOS, and $IL-1{\beta}$ in cells of the murine RAW 264.7 macrophages was investigated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, reverse transcription-polymerase chain reaction (RT-PCR), $PGE_2$ immunoassay, and NO detection. The aqueous extract of Corydalis Tuber was shown to suppress $PGE_2$ production by inhibition on the LPS-stimulated enhancement of COX-2 enzyme activity, $IL-1{\beta}$, and iNOS expression in the RAW 264.7 macrophages. Present results suggest that Corydalis Tuber exerts anti-inflammatory and analgesic effects probably by suppressing of COX-2, iNOS, and $IL-1{\beta}$ expressions, resulting in inhibition of $PGE_2$ synthesis. Corydalis Tuber has anti-inflammatory and analgesic effects probably by suppressing of COX-2, iNOS, and $IL-1{\beta}$ mRNA expressions, resulting in inhibition of $PGE_2$ and NO synthesis.

• Archives of Reconstructive Microsurgery
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• v.9 no.2
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• pp.190-198
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• 2000

본 연구는 백서 복직근피판에 있어 허혈-재혈류 손상에 미치는 prostaglandin E1(PGE-1)의 예방효과를 분석 실험하였으며, 그 기전으로 내피세포의 intercellular adhesion molecule-1(ICAM-1)이 down regulation 됨을 확인하였다. 기존의 PGE-1은 혈관 확장 및 혈소판 응고 저하 등의 기전으로 피판 이식술 후 주로 사용하였으나, 허혈-재혈류 손상 시에 PGE-1 역할에 대한 연구는 잘 알려진바 없다. 허혈-재혈류 손상에 대한 기전은 현재 여러 가설로 설명되고 있으나, 최근 내피 세포와 백혈구의 역할이 주목을 받고 있다. 장시간 허혈 상태의 피판은 재혈류시 백혈구가 내피세포에 접착함으로써 직간접적인 경로로 독소를 생성하며, 결국 내피세포 및 주변조직의 괴사로 이어진다. 본 연구는 면역조직학 염색을 통한 내피세포의 ICAM-1 발현 억제와 그로 인한 백혈구의 내피세포 접착 억제를 그 기전으로 볼 수 있었으며, PGE-1을 술 중 투여함으로써 피판의 생존율을 향상시킬 수 있었다.

• 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.

• The korean journal of orthodontics
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• v.28 no.6 s.71
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• pp.915-926
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• 1998

The cytoskeleton has been shown to form a network, connecting the extracelluar matrix via integrin with the nucleus and the cytoplasmic constituents of the cell. It is therefore assumed that the cytoskeleton may mediate signals generated by perturbations originating in the matrix. The purpose of this study is to examine the effect of cytoskeletal change on osteoblastic cell activities. The author cultured osteoblastic cells obtained from neonatal mouse calvaria. The cells were teated with cytochalasin B(CB) or colchicine (COL) at four concentrations for 3 hours and after another 24 hours the conditioned media was collected and assayed for prostaglandin $E_2\;(PGE_2)$, interleukin-6(IL-6), tumor necrosis factor-$\alpha$ (TNF-$\alpha$) and matrix metalloproteinase-1(MMP-1). In addition, the cytoskeletal protein actin were observed by immuno-fluorescence. The results were as follows: 1. The production of $PGE_2$ showed the tendency to be increased in CB-treated group. $PGE_2$ was increased in COL-treated group dose-dependantly, 2. IL-6 production, in CB-treated group, was increased, except at 1.0 ${\mu}g/ml$. IL-6 was induced in COL-treated group. 3. TNF-$\alpha$ production was increased in CB-treated group, except at 1.0 ${\mu}g/ml$, and in COL-treated group, that was increased. 4. The MMP-1 production was decreased in CB-treated soup and was not changed in COL-treated group, which could be selectively visualized by immunoblotting with monospecific antibody. 5. The cytoskeletal actin stress fibers were disappeared and the cells showed to be rounded in CB-treated group. These results indicated that there are a relationship between the cytoskeletal rearrangements and osteoblastic cell activities, especially in release of paracrine/autocrine factors, such as $PGE_2$, IL-6, and TNF-$\alpha$.

• Journal of Acupuncture Research
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• v.25 no.2
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• pp.119-127
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• 2008

목적 : 골관절염치료에 빈용되는 유근피 약침액의 처치가 생쥐의 파골세포에 있어서 골재흡수의 저해에 미치는 영향을 알아보고자 하였다 방법 : 생쥐에게 유근피 약침액을 두개골 세포에 전, 후 처치하여 골재흡수에 대한 유근피 약침액의 억제 활성능을 검토하였다. 결론 : 염증성 cytokine 중 $IL-1{\beta}$ 유도인자인 PGE와 LPS처리로 $IL-1{\beta}$생성이 증가되었으나, 유근피 약침액 처치군은 이를 억제하였다. 유근피 약침액 전처리군에서도 $IL-1{\beta}$ 생성이 억제되었다. 유근피 약침액 처치군은 PGE2유발 $IL-1{\beta}$ 전사를 억제하였으며, PGE2 유발 $IL-1{\beta}$ 유도는 cAMP antagonist인 Rp-cAMP와 protein kinase A(PKA)저해제에 의해서도 억제되어 $IL-1{\beta}$ 발현에 cAMP, PKA 신호전달경로가 관여함을 시사하였다. 본 연구에서 유근피 약침액은 강한 항 관절염효과와 골재흡수 저해 활성이 있으며, 관절염 치료, 예방에 유의함을 밝힌 것으로 사료된다.