• The Korean Journal of Pain
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• v.24 no.4
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• pp.179-184
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• 2011

Background: The analgesic mechanisms of cyclooxygenase (COX)-2 inhibitors have been explained mainly on the basis of the inhibition of prostaglandin biosynthesis. However, several lines of evidence suggest that their analgesic effects are mediated through serotonergic or adrenergic transmissions. We investigated the roles of these neurotransmitters in the antinociception of a selective COX-2 inhibitor at the spinal level. Methods: DUP-697, a selective COX-2 inhibitor, was delivered through an intrathecal catheter to male Sprague-Dawley rats to examine its effect on the flinching responses evoked by formalin injection into the hindpaw. Subsequently, the effects of intrathecal pretreatment with dihydroergocristine, prazosin, and yohimbine, which are serotonergic, ${\alpha}1$ adrenergic and ${\alpha}2$ adrenergic receptor antagonists, respectively, on the analgesia induced by DUP-697 were assessed. Results: Intrathecal DUP-697 reduced the flinching response evoked by formalin injection during phase 1 and 2. But, intrathecal dihydroergocristine, prazosin, and yohimbine had little effect on the antinociception of intrathecal DUP-697 during both phases of the formalin test. Conclusions: Intrathecal DUP-697, a selective COX-2 inhibitor, effectively relieved inflammatory pain in rats. Either the serotonergic or adrenergic transmissions might not be involved in the analgesic activity of COX-2 inhibitors at the spinal level.

• Biomedical Science Letters
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• v.15 no.2
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• pp.141-146
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• 2009

Paclitaxel, an antimicrotubule agent, binds to beta-tubulin in the microtubule and stabilizes the polymer, thereby repressing dynamic instability. Here, we have demonstrated that microtubule cytoskeletal architecture involved in regulation of the COX-2 expression in chondrocyte treated with paclitaxel. Paclitaxel enhanced COX-2 expression and prostaglandin E2 production, as indicated by the Western blot analysis, reverse transcriptase PCR(RT-PCR) and immunofluorescence staining, and $PGE_2$ assay, respectively. In our previous data have shown that paclitaxel treatment stimulated activation of ERK-1/2 and p38 kinase(Im et al., 2009). SB203580, an inhibitor of p38 kinase, blocked the induction of COX-2 expression by paclitaxel. Also PD98059, an inhibitor of ERK-1/2 kinase was blocked the induced COX-2 expression. These results indicate that activation of ERK-1/2 and p38 kinase is required for COX-2 expression induced by paclitaxel in rabbit articular chondrocytes.

• Tuberculosis and Respiratory Diseases
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• v.67 no.4
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• pp.303-310
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• 2009

Background: Elevated expression of cyclooxygenase-2 (COX-2) and Polo-like kinase-1 (PLK-1) is observed in a wide variety of cancers. Augmented expression of COX-2 and enhanced production of prostaglandin $E_2(PGE_2)$ are associated with increased tumor cell survival and malignancy; COX-2 has been implicated in the control of human non-small cell lung carcinoma (NSCLC) cell growth. PLK-1 siRNA induced the cell death of lung cancer cells and the systemic administration of PLK-1 siRNA/atelocollagen complex inhibited the growth of lung cancer in a liver metastatic murine model. COX-2 and PLK-1 are involved in proliferation and in cell cycle regulation, and there is a significant correlation between their interaction in prostate carcinoma. Methods: In this study, we investigated the pattern of COX-2 and PLK-1 expression in NSCLC, after treatment with IL-1$\beta$, COX-2 inhibitor and PLK-1 siRNA. Results: Expression of PLK-1 was decreased in A549 COX-2 sense cells, and was increased in A549 COX-2 anti-sense cells. Knock out of PLK-1 expression by PLK-1 siRNA augmented COX-2 expression in A549 and NCl-H157 cells. When A549 and NCI-H157 cells were treated with COX-2 inhibitor on a dose-dependent basis, PLK-1 and COX-2 were reduced. However, when the expression of COX-2 was induced by IL-1$\beta$, the production of PLK-1 decreased. Conclusion: These results demonstrate that COX-2 and PLK-1 are regulated and inhibited by each other in NSCLC, and suggest that these proteins have a reverse relationship in NSCLC.

• 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.

• YAKHAK HOEJI
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• v.46 no.6
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• pp.375-380
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• 2002

In this study, newly designed COX-2 inhibitors, synthetic derivatives of benzothiazine-3-carboxamide, were screened in vitro for selectivity of COX-1 and COX-2 inhibition properties. 7-Bromo-1,2-benzoisothiazine derivatives were obtained from 4-bromotoluene over the chlorosulfonation, amination and oxidation. And benzothiazine ring was synthesized through Gabriel-Colmann rearrangement reaction. To evaluate inhibitory effect of COX-2, synthetic derivatives of benzothiazine-3-carboxamide were tested with accumulation of prostaglandin by lipopolysaccharide in aspirin-treated murine macropharge cell. Some of the synthesized lead compounds have potentially shown the structure-activity relationship for selectivity of COX-2 inhibition activity.

• Archives of Pharmacal Research
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• v.22 no.4
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• pp.372-379
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• 1999

A series of disubstituted 4,5-polymethylenepyrazoles were synthesized and evaluated their inhibitory activities against COX-2. Some compounds showed strong (0.3 nM) inhibitory activity on COX-2 and were found somewhat selective (up to 16) on COX-2 over COX-1.

• Proceedings of the Korean Society of Toxicology Conference
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• 2002.05a
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• pp.90-90
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• 2002

In order to understand the mechanism of action of TCDD, we have examine the effect of COX-inhibitors on Cyp1a1 activity. We observed the effect of COX-inhibitor on EROD activity in C57BL/6 mouse in vovo. And we also evaluated the effect of COX-inhibitors on mouse cyp1a1 promoter activity in Hepa cell.(omitted)

• YAKHAK HOEJI
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• v.52 no.1
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• pp.43-47
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• 2008

To determine the regulatory roles of PDE4 inhibitor on LPS-induced osteoclastogenesis, we investigated the effect of a PDE4 inhibitor on osteoclast formation in the presence of LPS. A specific PDE4 inhibitor, rolipram, increased LPS-induced osteoclast formation in cocultures. To verify that whether rolipram acts indirectly on osteoblasts, we investigated the TRANCE and COX-2 mRNA expression levels in osteoblasts. Treatment of rolipram increased the expression of TRANCE and COX-2 mRNA in osteoblasts stimulated by LPS. On the contrary, rolipram did not augment the number of osteoclasts differentiated from bone marrow cells by LPS. In conclusion, the stimulation of LPS-induced osteoclast formation by the PDE4 inhibitor are attributable to its indirect effect on osteoblasts, not to their direct effect on bone marrow-derived osteoclast precursors.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.292.1-292.1
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• 2002

In order to understand the mechanism of action of TCDD. we have examined the effect of COX-inhibitors on cypla1 activity. We observed the effect of COX-inhibitor on EROD activity in C57BL/6 mouse in vovo. And we also evaluated the effect of COX-inhibitors on cypla1 mRNA. mouse cyplal promoter activity and EROD activity in Hepa cell. When Aspirin were pretreated with 3MC in vivo, the EROD activity that was stimulated by 3MC was inhibited. (omitted)

• Nutritional Sciences
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• v.8 no.1
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• pp.16-22
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• 2005

The present study examined the effects of cyclooxygenase-2 (COX-2) inhibitor celecoxib or soy-isoflavones in the presence of estrogen on apoptosis related gene expression, COX-2 and mapkinase in 48-week old female rats. Expressions of bel-2 and bax proteins, which are known to be involved in the regulation of apoptosis, were investigated in mammary glands and heart tissues. The elevated expression of bel-2 expression was observed in mammary glands of celecoxib supplemented rats as well as soy-isoflavones. The mammary glands bel-2/bax ratio was found to be higher in celecoxib or soy-isoflavones supplemented rats. However, in heart tissues, expression of bel-2 and bax was in the order of control, celecoxib and soy-isoflavones. The up-regulation of COX-2 was observed in celecoxib or soy-isoflavones in mammary glands. 'The similar trend was not displayed with the mapkinase expression. In heart tissues, the down-regulation of COX-2 as well as mapkinase was observed in celecoxib or soy-isoflavones supplemented rats. Soy-isoflavones and celecoxib both had a similar regulatory pattern of bel-2, bax and COX-2 in mammary glands, and in heart tissues, only COX-2 exhibited a similar down-regulatory properly. These findings revealed that in estrogen sufficient state, celecoxib and soy-isoflavones might not exhibit proapoptotic potential or COX-2 inhibition in normal mammary glands.