• Natural Product Sciences
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• 제3권1호
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• pp.19-28
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• 1997

Constitutive cyclooxygenase (COX-I) is present in cells under physiological conditions, whereas inducible cyclooxygenase (COX-II) is induced by some cytokines, mitogens, and endotoxin presumably in pathological conditions such as inflammation. We have evaluated the inhibitory effects of solvent fractionated extracts of natural products on the activities of COX-I and COX-II. Oxygen uptake COX assay was performed, as a primary screening from the tissue extracts of bovine seminal vesicles (BSV), by monitoring the initial rate of oxygen uptake using an oxygen electrode. Additionally, we evaluated plant extracts for the inhibitory effects of COX-I (in HEL cells) and COX-II (in lipopolysaccharide activated J774A.1 macrophages) using thin layer chromatography of prostanoids produced from $^{14}C-labelled$ arachidonic acid (AA). The use of such models of COX-I and COX-II assay will lead to the identification of specific inhibitors of cyclooxygenases with presumably less side effects than present therapies. Inhibitory effects of 50 kinds of plant extracts on the COX-I and COX-II activities were determined and the active fractions were found in the ethyl acetate fractions of Dryopteris crassirhizoma (roots), Amomum cardamomum (roots), Triticum aestivum (seeds), Perilla sikokiana (leaves), Anemarrhena asphodeloides (roots). Especially, the ethyl acetate fraction of Dryopteris crassirhizoma (roots), which exhibited the strong inhibition against BSV COX $(IC_{50},\;65.4\;{\mu}g/ml)$, COX-I $(IC_{50},\;8.5\;{\mu}g/ml)$, and COX-II $(IC_{50},\;17.2\;{\mu}g/ml)$, is under investigation to isolate active principles using activity-guided fractionation method.

• 한국수자원학회논문집
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• 제36권2호
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• pp.153-159
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• 2003

I-D-F곡선을 유도할 때 강우자료의 보유연한이 충분하지 않을 경우 지속시간별 강우강도의 변화가 매끄럽게 연결되지 못하는 경우가 발생하기도 한다. 특히 곡선에서, 상대적인 장시간에 강우강도가 크게 되는 문제는 실무적으로 I-D-F 곡선을 이용하는데 큰 혼란을 야기 시킨다. 본 연구에서는 강우자료를 Box-Cox변환을 이용하여 지속시간과 강우강도의 상관관계를 통해 이러한 문제를 해결하는 방법을 제시한다. 산청과 영천의 강우자료에 대한 분석결과 Box-Cox 변환의 실효성을 확인할 수 있었다.

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.320.2-320.2
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• 2002

Macrophages activated by lipopolysaccharide (LPS) are known to induce several proinflammatory proteins including COX-2. iNOS and TNF which produce chemical mediators involved in inflammatory response. Sophoricoside and its analogs (genistin, genistein and orobol) from Sophora japonica (Leguminosae) showed differential inhibitory effects on COX-1 and 2 activities. Sophoricoside and genistin shwoed IC50 values of 4 uM and 6 uM on COX-2 activity and of 1,497 uM and 135 uM on COX-1 activity, respectively. Genistein and orobol showed IC50 values of 3 uM on COX-2 activity and of 28 uM and 18 uM on COX-1 activity. respectively. Therefore. the legume isoflavonoids to be selective COX-2 inhibitors. However. sophoricoside and its analogs did not show inhibitory effects of COX-2, iNos and TNF transcripts. which were identified by the RT-PCR.

• 치위생과학회지
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• 제15권6호
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• pp.753-760
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• 2015

숙주 면역 반응과 면역 체계는 치주 질환에 대한 개인의 감수성의 주요 원인이다. 세균 감염과 흡연은 치주 조직의 파괴의 원인과 진행에 관여하는 중요한 환경 위험 요인이다. 따라서, 본 연구는 사람 치주인대세포에서 LPS와 니코틴이 전염증성 사이토카인인 iNOS/COX-2의 발현과 NO/$PGE_2$ 생산에 미치는 영향을 알아보고 NFATc1가 어떤 기전으로 항염작용을 하는지 밝히고자 하였다. LPS와 니코틴을 처리한 사람 치주인대세포에서 iNOS/COX-2의 발현과 함께 NO/$PGE_2$ 생산은 증가되었다. NFATc1 inhibitor인 CsA는 LPS와 니코틴에 의해 유도되는 iNOS/COX-2의 발현과 함께 NO/$PGE_2$ 생산을 감소시켰다. 이러한 연구 결과로 볼 때, NFAT signaling pathway가 LPS와 니코틴에 의한 iNOS/COX-2의 발현을 조절하여 NO/$PGE_2$ 매개 염증에 대해 방어할 수 있다고 생각된다.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 2003년도 Annual Meeting of KSAP : International Symposium on Pharmaceutical and Biomedical Sciences on Obesity
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• pp.101-101
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• 2003

Prostaglandins (PGs) and nitric oxide (NO) produced by inducible cyclooygenase (COX-2) and nitric oxide synthase (iNOS), respectively, have been implicated as important mediators in the process of inflammation and carcinogenesis. On this line, the potential COX-2 or iNOS inhibitors have been considered as anti-inflammatory and cancer chemopreventive agents. In our continuing efforts of searching for novel cancer chemopreventive agents from natural products, we isolated natural sesquiterpenoids as potential COX-2 and iNOS inhibitors in cultured lipopolysaccharide (LPS)-activated mouse macrophage RAW 264.7 cells. Alantolactone, a natural eudesmane-type sesquiterpenoid, exhibited a potent inhibition of COX-2 (IC50 = 0.4 $\mu\textrm{g}$/$m\ell$) and iNOS activity (IC50 = 0.08 $\mu\textrm{g}$/$m\ell$) in the assay system determined by PGE2 and NO accumulation, respectively. The inhibitory potential of alantolactone on the PGE2 and NO production was well coincided with the suppression of COX-2 and iNOS protein and mRNA expression in LPS-induced macrophages. Furthermore, alantolactone inhibited NF-kB but not AP-l binding activity on nuclear extracts evoked by LPS-stimulated macrophage cells, suggesting the possible involvement of NF-kB in the regulation of COX-2 and iNOS expression. In further study with COX-2-expressing human colon HT-29 cells, alantolactone inhibited the cell proliferation, down-regulated COX-2, and inhibited the ERK phosphorylation in the early time. These results suggest that a natural sesquiterpenoid alantolactone might be a potential lead candidate for further developing COX-2 or iNOS inhibitor possessing cancer chemopreventive or anti-inflammatory activity

• Journal of Microbiology and Biotechnology
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• 제18권12호
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• pp.1990-1996
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• 2008

Astaxanthin has shown antioxidant, antitumor, and anti-inflammatory activities; however, its molecular action and mechanism in the nervous system have yet to be elucidated. We examined the in vitro effects of astaxanthin on the production of nitric oxide (NO), as well as the expression of inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2) in lipopolysaccharide (LPS)-stimulated BV2 microglial cells. Astaxanthin inhibited the expression or formation of nitric oxide (NO), iNOS and COX-2 in lipopolysaccharide (LPS)-stimulated BV-2 microglial cells. Astaxanthin also suppressed the protein levels of iNOS and COX-2 in LPS-stimulated BV2 microglial cells. These results suggest that astaxanthin, probably due to its antioxidant activity, inhibits the production of inflammatory mediators by blocking iNOS and COX-2 activation or by the suppression of iNOS and COX-2 degradation.

• 생명과학회지
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• 제19권6호
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• pp.818-824
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• 2009

급성 폐손상시 아스피린이 나타내는 염증 억제작용의 기전을 이해하기 위하여 쥐에서 장 허혈-재관류에 의한 급성 폐손상을 유발하여 phospholipase $A_{2}$ 억제제인 mepacrine과 아스피린의 효과를 비교하였다. 내독소 처치시 A549 세포와 RAW264.7 세포에서 cyc1ooxygenase-2 (COX-2)의 발현이 증가했는데, RAW264.7 세포의 반응이 더 크게 나타났다. 장의 허혈-재관류에 의해 장관 및 폐장조직에서 myeloperoxidase 활성도가 증가하여 염증성 호중구의 침윤이 증가했음을 보여 주었다. 조직 소견상에서도 조직 손상과 염증세포의 침윤이 관찰되었으며, 이는 아스피린 또는 mepacrine 전처치 시 억제 되었다. NADPH oxidase 억제작용이 있는 apocynin과 p38 MAPK 억제제인 SB203580은 A549 세포와 RAW264.7 세포의 LPS에 의한 COX-2 발현을 억제시켰으며 RAW264.7 세포에서 더 크게 억제되었다. 이상의 결과를 통해서 아스피린이 급성 폐손상의 예방목적으로 사용될 수 있다고 보여지며, RAW264.7 세포와 A549 세포에서 COX-2 발현은 다른 특성을 보여서 다른 조절기전이 있을 것으로 생각된다.

• IMMUNE NETWORK
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• 제11권6호
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• pp.364-367
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• 2011

Background: Prostaglandins (PGs) play pathogenic and protective roles in inflammatory diseases. The novel concept of PGs as immune modulators is being documented by several investigators. By establishing an in vitro experimental model containing human follicular dendritic cell-like cells, HK cells, we reported that HK cells produce prostaglandin $E_2$ ($PGE_2$) and prostaglandin $I_2$ ($PGI_2$) and that these PGs regulate biological functions of T and B cells. Methods: To investigate the respective contribution of cyclooxygenase-1 (COX-1) and COX-2 to $PGE_2$ and $PGI_2$ production in HK cells, we performed siRNA technology to knock down COX enzymes and examined the effect on PG production. Results: Both $PGE_2$ and $PGI_2$ productions were almost completely inhibited by the depletion of COX-2. In contrast, COX-1 knockdown did not significantly affect PG production induced by lipopolysaccharide (LPS). Conclusion: The current results suggest that mPGES-1 and PGIS are coupled with COX-2 but not with COX-1 in human follicular dendritic cell (FDC) and may help understand the potential effects of selective COX inhibitors on the humoral immunity.

• The Korean Journal of Physiology and Pharmacology
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• 제9권4호
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• pp.215-221
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• 2005

We investigated the effects of testosterone and dihydrotestosterone on inflammatory response of iNOS and COX-2 expression in rat vascular smooth muscle cells. Rat vascular smooth muscle cells (VSMC) stimulated with bacterial lipopolysaccharide $(LPS;\;10{\mu}g/ml)$ for 24 hours were incubated with increasing amounts of testosterone and dihydrotestosterone (1 and 100 nM). LPS was found to induce inflammatory response of iNOS and COX-2 mRNA and protein in VSMC. These processes were affected by male sex steroid hormones. For 3 hours, however, pretreatment of the cells with 100 nM each of testosterone and dihydrotestosterone suppressed LPS induced iNOS and COX-2 protein expression. RT-PCR analysis revealed that testosterone and dihydrotestosterone did not inhibit mRNA expression of iNOS and COX-2 stimulated by 24 hours of LPS incubation. Proliferation rate was slower in VSMC treated with testosterone and dihydrotestosterone. Testosterone enhanced androgen receptor expression, and LPS significantly reduced androgen receptor protein expression in VSMC. These results indicate that the expression of both iNOS and COX-2 proteins was suppressed by testosterone and dihydrotestosterone in LPS stimulated VSMC and leading to reduction of vascular inflammation.

• 대한한의학방제학회지
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• 제12권2호
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• pp.163-173
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• 2004

Chelidonii Herba (CHE, Baek-gul-chae in Korean), which has its original description in Gu-Hwang-Bon-Cho, a classic book of oriental Herbal book, is widely used in the treatment of stomach cancer, jaundice, gasrtic ulcer, edema and stomach pain, in Korea, Japan and China. The present study was conducted to evaluate the effect of CHE on the nitric oxide (NO) production, iNOS and COX-2 expression in lipopolysaccharide - activated Raw 264.7 cells. After the treatment of CHE, NO production was monitored by measuring the nitrite content in culture medium, cell viability was measured by MIT assay. COX-2 and iNOS were determined by lmmunoblot analysis. The production of nitric oxide was significantly inhibited by pretreatment (1h) with CHE (0.1-0.3 mg／ml) on LPS-activated Raw264.7 cells. The expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase 2 (COX-2) protein were up-regulated by LPS, but the increased levels of iNOS and COX-2 were inhibited by pretreatment of CHE (0.1-0.3 mg／ml), respectively. Thus, the present data suggest that CHE may play an important role in adjunctive therapy in Gram-negative bacterial infections.