• Molecules and Cells
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• 제23권3호
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• pp.398-404
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• 2007

Cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) are involved in various pathophysiological processes such as inflammation and carcinogenesis. In a search for inhibitors of COX-2 and iNOS production we found that extracts of Stewartia koreana strongly inhibited NO and $PGE_2$ production in LPS-treated macrophage RAW 264.7 cells. We have now shown that the mRNA and protein levels of iNOS and COX-2 are reduced by the Stewartia koreana extract (SKE). SKE inhibited expression of an NF-${\kappa}B$ reporter gene in response to LPS, and gel mobility shift assays revealed that SKE reduced NF-${\kappa}B$ DNA-binding activity. The extract also inhibited LPS-induced phosphorylation of $I{\kappa}B-{\alpha}$ and nuclear translocation of p65. Administration of the extract reduced the symptoms of arthritis in a collagen-induced arthritic mouse model. These results indicate that Stewartia extracts contain potentially useful agents for preventing and treating inflammatory diseases.

• 대한약리학회지
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• 제30권3호
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• pp.337-342
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• 1994

선천성고혈압흰쥐 (SHR)에서 angiotensin converting enzyme inhibitor (ACEI)를 처치하면 내피세포 의존적 이완이 증진된다고 알려져 있다. 본 실험은 angiotensin II가 nitric oxide (NO)와 관련되어 일어나는 적출 대동맥의 이완력에 변화를 주는지 관찰하고자 angiotensin II 작용 억제를 위해 angiotensin II 수용체 차단제인 losartan과 ACEI인 enalapril을 사용하였으며 혈관에서의 NO는 혈관내피세포에서 생성되는 constitutive NO와 주로 혈관 평활근에서 LPS에 생성되는 inducible NO가 있으므로 이들 양자에 대한 angiotensin II의 작용을 검토하였다. 2주간 losartan (30 mg/kg/day)과 enalapril (10 mg/kg/day)을 처치한 경우 acetylcholine $(10^{-9}\;to\;10^{-5}\;M)$과 histamine $(10^{-8}\;to\;10^{-4}\;M)$에 의한 이완 반응이 증가되었으나 90분간 적출 대동맥에 losartan $(10^{-4}\;M)$ 을 노출시킨 경우는 이완 반응에 변화가 없었다. Phenylephrine $(10^{-7}\;M)$ 을 2시간 간격으로 반복 투여하여 수축시킨 경우 LPS $(100\;{\mu}g/ml)$처치에 의해 시간이 지남에 따라 수축력이 감소되었고 대조군에서는 수축력이 감소되지 않았다. LPS 처치에 따른 phenylephrine에 의한 수축력의 감소는 enalapril이나 losartan을 2주간 처치한 경우에도 영향을 받지 않았다. 이상의 결과로 미루어 아마도 losartan의 내피세포에 대한 작용은 constitutive NO 생성을 증가시키나 inducible NO 생성에는 영향을 미치지 않을 것으로 여겨진다.

• 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.

• 생명과학회지
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• 제28권5호
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• pp.509-516
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• 2018

노각나무(Stewartia koreana) 잎 에틸아세테이트 분획으로부터 quercetin (1), quercitrin (2), hyperin (3), quercetin-3-O-(6"-O-galloyl)-${\beta}$-D-galactopyranoside (4), kaempferol-3-o-[2",6"-di-o-(trans-p-coumaroyl)]-${\beta}$-D-glucopyranoside (5)의 5종의 플라보노이드를 분리하였으며, 이들 5종 성분의 염증 반응에 대한 활성을 분석하기 위하여 LPS를 처리한 대식세포에서 산화질소(NO) 생성 억제활성을 측정하였다. 이들 5종 성분 중 compound 4, 5는 노각나무에서 처음으로 분리된 것으로 항염증 활성에 대한 보고도 없다. 분광분석법으로 확인된 노각나무 잎 유래 성분들은 LPS 처리한 대식세포의 NO 생성을 유의적으로 저해하였으며, 특히 kaempferol-3-o-[2",6"-di-o-(transp-coumaroyl)]-${\beta}$-D-glucopyranoside (5)는 가장 강한 억제효과(17.17%, 5.0%, 3.92%, 6.32% and 63.35% inhibition of compound 1, 2, 3, 4 and 5 at $10{\mu}g/ml$)를 나타냈다. 또한, 이러한 NO 생성 억제효과는 inducible nitric oxide synthase(iNOS) 단백질 발현 억제를 통한 것으로 나타났다. 따라서, 본 연구에서 새로 분리된 플라보놀인 kaempferol-3-o-[2",6"-di-o-(trans-p-coumaroyl)]-${\beta}$-D-glucopyranoside (5)는 노각나무 잎의 항염증 활성을 나타내는 주요 물질로 사료된다.

• Advances in Traditional Medicine
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• 제10권4호
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• pp.310-318
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• 2010

Verbena officinalis (Verbenaceae) has been used as herbal medicine or health supplement in both Western and Eastern countries for centuries. In the present study, we examined the anti-inflammatory and antioxidant activities of the methylene chloride fraction of V. officinalis (VMC). To elucidate the anti-inflammatory properties of VMC, we investigated the inhibition effects of nitric oxide production in interferon-gamma (IFN-$\gamma$) and lipopolysaccharide-stimulated mouse peritoneal macrophages. VMC suppressed nitric oxide production, inducible nitric oxide synthase and cyclooxygenase-2 expression dose-dependently without notable cytotoxicity. In various radical scavenging assays, VMC exhibited strong scavenging effect on DPPH radical, superoxide radical, nitric oxide radical and 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) radical. VMC also showed potent reducing power. These findings strongly suggest that VMC may be beneficial in oxidative stress-mediated inflammatory disorders.

• Archives of Pharmacal Research
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• 제27권3호
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• pp.314-318
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• 2004

Microglia are the major inflammatory cells in the central nervous system and become activated in response to brain injuries such as ischemia, trauma, and neurodegenerative diseases including Alzheimer's disease (AD). Moreover, activated microglia are known to release a variety of proinflammatory cytokines and oxidants such as nitric oxide (NO). Minocycline is a semi-synthetic second-generation tetracycline that exerts anti-inflammatory effects that are completely distinct form its antimicrobial action. In this study, the inhibitory effects of minocycline on NO and prostaglandin E$_2$ (PGE$_2$) release was examined in lipopolysaccharides (LPS)-challenged BV2 murine microglial cells. Further, effects of minocycline on inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expression levels were also determined. The results showed that minocycline significantly inhibited NO and PGE$_2$ production and iNOS and COX-2 expression in BV2 microglial cells. These findings suggest that minocycline should be evaluated as potential therapeutic agent for various pathological conditions due to the excessive activation of microglia.

• Preventive Nutrition and Food Science
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• 제15권2호
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• pp.92-97
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• 2010

Luteolin and chicoric acid are the most abundant phytochemicals in dandelion (Taraxacum officinale) leaf. In this study, four kinds of extraction methods [hot water, ambient temperature (AT) water, ethanol, and methanol] were applied to analyze the contents of both phytochemicals and verify their anti-inflammatory and antioxidative activities. The methanol extract showed the most potent nitric oxide (NO) inhibitory effect. The luteolin and chicoric acid concentrations were 3.42 and $12.86\;{\mu}g/g$ dandelion leaf in the methanol extract. The NO-suppressive effect of luteolin and chicoric acid was identified in a dose-dependent manner with $IC_{50}$ values of $21.2\;{\mu}M$ and $283.6\;{\mu}M$, respectively, in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells without cytotoxicity. Malondialdehyde (MDA) concentration, as an index for free radical injury on cell membrane, was also dose-dependently inhibited by the two compounds. The suppressive effect was further examined using mRNA and protein expression levels, which were attributable to the inhibition of inducible nitric oxide synthase (iNOS). These results suggest that two phytochemicals in dandelion leaf, luteolin and chicoric acid, may play an important role in the amelioration of LPS-induced oxidative stress and inflammation.

• Archives of Pharmacal Research
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• 제25권2호
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• pp.151-153
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• 2002

Three pseudoguaianolide type sesquiterpenes, bigelovin(1), 2,3-dihydroaromaticin (2), and ergolide (3) were isolated as inhibitory constituents against inducible nitric oxide synthase (iNOS) from the flowers of Inula britannica var. chinensis. Bigelovin (1) exhibited a highly potent inhibitory activity on lipopolysaccharide (LPS)-induced iNOS in murine macrophage RAW 264.7 cells with an $IC_{50}$ value of 0.46 mM, which is about 8 times more potent than the known selective inhibitor of iNOS, $L-N^6-(1-iminoethyl)Iysine{\;}(IC_{50}{\;}3.49{\;}{\mu}M)$. 2,3-Dihydroaromaticin (2) and ergolide (3) also exhibited potent inhibitory activities on LPS-induced iNOS with $IC_{50}$ values of 1.05 and $0.69{\;}{\mu}M$, respectively.

• 약학회지
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• 제57권6호
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• pp.388-393
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• 2013

Previously, we have reported that lovastatin, an inhibitor of 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase, increased melanin synthesis through intracellular $Ca^{2+}$ release in B16 cells. In this study we investigated the possible involvement of nitric oxide (NO) in the mechanism of lovastatin-induced melanogenesis. Lovastatin elevated NO formation in a dose-dependent manner. Treatment with mevalonate, farnesyl pyrophosphate (FPP) and geranylgeranyl pyrophosphate (GGPP), precursors of cholesterol, did not significantly alter the lovastatin-induced NO production, suggesting that inhibition of cholesterol metabolism may not be involved in the mechanism of this action of lovastatin. Both NO formation and melanogenesis induced by lovastatin was significantly suppressed by treatment with $N^G$-nitro-L-arginine methyl ester (L-NAME) and 2-(4-carboxy-2-phenyl)-4,4,5,5-tetramethylinidazoline-1-oxyl-3-oxide (cPTIO), an inhibitor of NO synthase and a NO scavenger, respectively. The lovastatin-induced NO production was significantly affected not by EGTA, an extracellular $Ca^{2+}$ chelator, but by an intracellular $Ca^{2+}$ chelator (BAPTA/AM) and intracellular $Ca^{2+}$ release blockers (dantrolene and TMB-8). Taken together, these results suggest that lovastatin may induce melanogenesis through NO formation mediated by intracellular $Ca^{2+}$ release in B16 cells. These results further suggest that lovastatin may be a good candidate for the therapeutic application of various hypopigmentation disorders.

• 생명과학회지
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• 제23권6호
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• pp.736-742
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• 2013

Achyranthoside E dimethyl ester (AEDE)는 Achyranthes japonica에서 분리한 oleanolic acid glycoside이다. 본 연구에서는 대식세포에서 lipopolysaccharide (LPS)로 인한 nitric oxide (NO)의 생성에 미치는 AEDE의 효과를 관찰하고 그 작용 기전을 연구하였다. AEDE는 NO 생성과 inducible NO synthase (iNOS) 발현을 억제하였으며 세포에 독성을 유도하지 않았다. 또한 AEDE는 heme oxygenase-1 (HO-1)의 발현을 유도하였으며, HO-1 siRNA를 처리했을 때 AEDE가 iNOS의 발현을 억제하지 못하였다. AEDE는 HO-1의 발현에 관여하는 전사인자인 nuclear factor E2-related factor 2 (Nrf2)를 핵으로 이동시켰다. 한편 AEDE에 의한 HO-1의 발현은 phosphatidylinositol 3-kinase (PI-3K) 및 extracellular signal regulated kinase (ERK1/2) 억제제에 의해 감소되었으며, AEDE가 Akt와ERK1/2의 인산화를 유도하였다. 이상의 결과를 종합해보면, AEDE는 대식세포에서 PI-3K/Akt/ERK-Nrf2 신호전달과정을 통해 HO-1의 발현을 유도함으로써 NO와 같은 염증매개물질의 생성을 억제한다는 것을 알 수 있다. 이러한 연구결과는 AEDE가 항염증제로 사용될 수 있음을 시사한다.