• Proceedings of the PSK Conference
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• 2002.10a
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• pp.177-178
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• 2002

Chemoprevention, one of the most innovative and promising areas of cancer research, refers to the prevention of cancer through pharmacologic or nutritional intervention. Recently, considerable attention has been focused on the role of cyclooxygenase-2 (COX-2) in the carcinogenesis as well as inflammation. Inappropriate up-regulation of COX-2 is implicated in the pathophysiology of certain types of human cancers. (omitted)

• Proceedings of the Korean Society of Life Science Conference
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• 2005.04a
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• pp.228-228
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• 2005

• Proceedings of the Korea Environmental Mutagen Society Conference
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• 2002.05a
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• pp.87-87
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• 2002

• Proceedings of the PSK Conference
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• 2000.10a
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• pp.189.2-189.2
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• 2000

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.213.1-213.1
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• 2003

Alpha-viniferin was isolated from Carex humilis (Cyperaceae), and showed anti-inflammatory effects on carrageenin or histamine-induced paw edema in mice. To understand mode of the anti-inflammatory action. effects of alpha-viniferin on cyclooxygenase (COX)-2, iNOS, oxygen radicals and proinflammatory cytokines have been analyzed. Alpha-viniferin showed selective inhibitory effect with an IC50 value of 5 $\mu\textrm{m}$ on COX-2 activity but showed weak inhibitory effect on the synthesis of COX-2 transcript which was identified by RT-PCR. (omitted)

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.250.1-250.1
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• 2003

In this work, we have conducted 3D-QSAR studies on a series of acanthonic acid derivatives that act as COX-2 inhibitors, using two different methods: comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA). CoMFA and CoMSIA analysis of twenty five pimarane analogues produced good models with high predictive abilities. (omitted)

• Journal of Korean Neurosurgical Society
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• v.38 no.4
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• pp.287-292
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• 2005

Objective : Kainic acid[KA] enhances the expression of nitric oxide synthase, increases nitric oxide[NO], and thus evokes epileptic convulsion, which results in neuronal damage in the rat brain. NO may stimulate cyclooxygenase type-2 [COX-2] activity, thus producing seizure and neuronal injury, but it has also been reported that KA-induced seizure and neurodegeneration are aggravated on decreasing the COX-2 level. This study was undertaken to investigate whether the suppression of NO using the NOS inhibitor, N-nitro-L-arginine methyl ester[L-NAME], suppresses or enhances the activity of COX-2. Methods : Silver impregnation and COX-2 immunohistochemical staining were used to localize related pathophysiological processes in the rat forebrain following KA-induced epileptic convulsion and L-NAME pretreatment. Post-injection survival of the rat was 1, 2, 3days and 2months, respectively. Results : After the systemic administration of KA in rats, neurodegeneration increased with time in the cornu ammonis [CA] 3, CA 1 and amygdala, as confirmed by silver impregnation. On pretreating L-NAME, KA-induced neuronal degeneration decreased. COX-2 enzyme activities increased after KA injection in the dentate gyrus, CA 3, CA 1, amygdala and pyriform cortex, as determined by COX-2 staining. L-NAME pretreatment prior to KA-injection, caused COX-2 activities to increase compared with KA- injection only group by 1day and 2days survival time point. Conclusion : These results suggest that L-NAME has a neuroprotective effect on KA-induced neuronal damage, especially during the early stage of neurodegeneration.

• Journal of Nutrition and Health
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• v.38 no.1
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• pp.30-39
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• 2005

The effects of different concentrations of estrogen supplementation to mature female rats or estrogen supplementation to ovariectomized rats on cyclooxygenase-2 (COX-2) expression, PGE$_2$ production and mapkinases expression were investigated in experimentally induced atherogenic rats with feeding a high fat. high cholesterol diet. In the first experiment using 48-week old mature rats, the supplementation of three different levels of estrogen was compared to the basal diet. The high concentration of estrogen supplementation induced the marked up-regulation of COX-2 protein and the increase in plasma PGE$_2$ production and this seems to be followed by the up-regulation of p38 among mapkinases. The regulation of bax showed in a reverse trend of COX-2 in heart tissues of mature female rats. In the second ex-perimental system, female Sprague-Dawley rats were bilaterally ovariectomized; sham-operated animals were used as controls. Three weeks later, the animals were supplied with basal diet to sham-operated control group and ovariectomized control group, and estrogen supplemented diet to ovariectomized group for an eight-week experimental period. In a group supplemented with a medium dose of estrogen, COX-2 expression was up-regulated. This up-regulation was accompanied by the elevated expression of pERK1/2. Bax was increased in estrogen-fed animals indicating bax might be involved in estrogen feeding state in ovariectomized rats. Further investigations on the relationship between COX-2 and biological activities such as vasodilation by estrogen are required in in vivo system of female rats at the various physiological states.

• Journal of Life Science
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• v.22 no.9
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• pp.1137-1144
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• 2012

Inflammation is a host defense mechanism that is activated in response to harmful substances or pathogens. However, an excessive inflammatory response is a problem in itself. Macrophages secrete inflammatory mediators such as nitric oxide (NO) or cytokines through various pathways such as the nuclear factor kappa B (NF-${\kappa}B$)-activated pathway after recognizing pathogen-like lipopolysaccharides (LPSs). In this study, anti-inflammatory effects of Eupatorium chinensis var. simplicifolium (EUC) extracts were investigated using LPS-stimulated RAW 264.7 macrophages. The EUC root extract significantly reduced NO production, inducible nitric oxide synthase (iNOS) expression, and cyclooxygenase-2 expression in a concentration-dependent manner. In addition, the EUC root extract reduced phosphorylation of mitogen-activated protein kinases and protein kinase B, which is upstream of NF-${\kappa}B$. The EUC root extract also reduced the degradation of inhibitory kappa B. These results indicate that EUC root extract exerts anti-inflammatory effects, which are mediated by inhibition of iNOS expression and the NF-${\kappa}B$ pathway.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.9
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• pp.4453-4458
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• 2012

Angiogenesis plays a significant role in colorectal cancer (CRC) and cyclooxygenase-2 (COX-2) appears to be involved with multiple aspects of CRC angiogenesis. Our aim was to investigate the inhibitory effects of Tan II-A (Tanshinone II-A, Tan II-A) on tumor growth in mice, as well as alteration of expression of COX-2 and VEGF in CRC. We established the mice xenograft model of C26 CRC cell line, and injected 0.5, 1, 2mg/kg of Tan II-A and 1mg/kg of 5-FU in respectively in vivo. Then, we assayed tumor weight and volume, and evaluated microvascular density and expression of VEGF. COX-2 promoter and COX-2 plasmids were transfected into HCT-116 cells, followed by detection of COX-2 promoter activity by chemiluminescence, and detection of COX-2 mRNA expression by fluorescence quantitative PCR. Taken together, the results showed Tan II-A could inhibit tumor growth and suppress the VEGF level in vivo. HCT-116 cell experiments showed marked inhibitory effects of Tan II-A on COX-2 and VEGF in a dose-dependent manner. The results indicate that Tan II-A can effectively inhibit tumor growth and angiogenesis of human colorectal cancer via inhibiting the expression level of COX-2 and VEGF.