• Korean Journal of Food Science and Technology
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• v.46 no.4
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• pp.511-515
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• 2014

In a screen for plant-derived inhibitors of nitric oxide (NO) production in lipopolysaccharide (LPS)-activated RAW 264.7 macrophage cells, a flavonol isolated from the chloroform extract of Alpinia officinarum was isolated. The structure of the flavonol was found to be 3,5,7-trihydroxy-2-phenylchromen-4-one (galangin, GLG) by using spectroscopy. GLG exhibited an inhibitory effect ($IC_{50}$ value: $26.8{\mu}M$) on NO production in LPS-stimulated RAW 264.7 murine macrophage cells. Moreover, GLG suppressed expressions of inducible nitric oxide synthase (iNOS) protein and mRNA in a dose-dependent manner.

• Biomedical Science Letters
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• v.18 no.3
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• pp.319-323
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• 2012

In recent years, egg allergy has been raised as the most prevalent food hypersensitivity in the pediatric population. One of the major egg allergens is ovalbumin (OVA) which is the major protein in egg white, comprising 54% of its total protein content. Parthenolide isolated from Tanacetum partheniumb has been used to treat many chronic diseases for many years. In the present report, we present biochemical evidence that parthenolide inhibits the nuclear factor-${\kappa}B$ (NF-${\kappa}B$) activation induced by OVA. Parthenolide also inhibits OVA-induced cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) expression. These data suggest new approaches for the efficient alleviation of the allergic symptoms.

• Biomedical Science Letters
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• v.19 no.3
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• pp.270-274
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• 2013

Egg allergy has been raised as the most prevalent food hypersensitivity in children. Ovalbumin (OVA), which is one of the major egg allergens, is the major protein in egg white. Isoliquiritigenin (ILG) is an active component present in licorice and has been used to treat many chronic diseases for many years. In this study, we present biochemical evidence that ILG inhibits OVA-induced nuclear factor-${\kappa}B$ (NF-${\kappa}B$) activation. ILG also inhibits OVA-induced cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) expression. These data suggest that ILG has anti-allergy effects.

• Archives of Pharmacal Research
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• v.22 no.4
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• pp.410-413
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• 1999

In bioassay-guided search for inducible nitric oxide synthase (iNOS) inhibitory compounds from higher plants of South Korea, two $\beta$-carboline (2) have been isolated form the cortex of Melia azedarach var. japonica. The structures of these compounds were elucidated on the basis of spectroscopic data. Compounds 1 to 2 showed marked inhibitory activity of iNOS on LPS-and interferon-${\gamma}$-stimulated RAW 264.7 cells.

• Journal of Periodontal and Implant Science
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• v.35 no.4
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• pp.1081-1095
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• 2005

본 연구는 치주질환 주요 병인균주 중의 하나인 Porphyromonas gingivalis의 세균내독소가 마우스 대식 세포주인 RAW264.7 세포에서의 nitric oxide의 생성과 iNOS의 발현에 미치는 영향을 분석하고 그 기전을 규명하기 위해 수행되었다. Butanol추출법과 phenol-water법에 의해 P. gingivalis 381로부터 세균내독소를 추출하였으며, NO의 생성은 배양 상층액 내의 nitrite 농도를 측정하여 결정하였다. 또한, iNOS의 western blot 분석과 reverse transcription (RT)-PCR 산물의 분석을 수행하였다. P. gingivalis의 세균내독소는 부가적인 자극이 없는 상태에서도 iNOS의 발현과 NO 생성을 유발하였으며, NF- ${\kappa}B$, microtubule polymerization, protein tyrosine kinase, 그리고 protein kinase C 등이 P. gingivalis 세균내독소에 의한 NO 생성에 간여하는 것으로 여겨진다. 또한, P. gingivalis 세균내독소에 의한 NO 생성에는 L-arginine이 요구되었다. P. gingivalis 세균내독소에 의한 NO 생성은 염증성 치주질환의 발병과 진행에 있어 중요한 역할을 하는 것으로 여겨진다.

• Biomedical Science Letters
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• v.25 no.2
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• pp.196-200
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• 2019

Effect of retinoids, i.e., all-trans retinoic acid and 13-cis retinoic acid, on the activity of nitric oxide synthase (NOS) was evaluated in human malignant keratinocytes to examine the possible correlation of retinoids with NOS activities. All-trans retinoic acid and 13-cis retinoic acid did not alter the nitric oxide (NO) production. However, in the presence of lipopolysaccharide (LPS, $1{\mu}g/mL$), they significantly increased NO release in a dose-dependent manner until 48 h at concentrations of $50{\sim}100{\mu}M$. The degree of upregulation of NO by all-trans retinoic acid and 13-cis retinoic acid increased up to 35% and 37%, respectively, compared to that by the control, which demonstrated the upregulation of LPS-inducible nitric oxide synthase (iNOS)-dependent generation of NO as well as showing a crucial link between retinoids-induced activity and NOS. Findings of this study now suggest that the upregulation of LPS-iNOS activity may be associated with modulation of retinoids-induced control of cellular developmental processes, which may produce new therapeutics of retinoids in the complexity of how NO affects human keratinocytes.

• YAKHAK HOEJI
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• v.43 no.2
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• pp.214-220
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• 1999

Present study was aimed to examine whether indomethacin affected the production of NO in the rat paw exudate by carrageenin. Paw edema and nitrite/nitrate levels in the paw exudate were maximal after 4 h and remained elevated up to 10 h, whereas indomethacin (10 mg/kg, po) significantly inhibited the carrageenin-induced paw edema and levels of nitrate in the paw exudate. However, paw edema and nitrite/nitrite levels were increased thereafter for 10 h. Indomethacin also enhanced the expression of iNOS mRNA and protein 4 h after carrageenin infection. Indomethacin inhibited the level of $PGE_2$ in the paw exudate in a time-dependent manner. These results suggest the possibility that indomethacin may potentiate expression of iNOS and subsequently increase nitrite/nitrate level in the late phase of carrageenin-induced rat paw inflammation possibly by suppressing cycloxygenase activity.

• Archives of Pharmacal Research
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• v.26 no.4
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• pp.301-305
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• 2003

Nitric oxide (NO) is an important bioactive agent that mediates a wide variety of physiological and pathophysiological events. NO overproduction by inducible nitric oxide synthase (iNOS) results in severe hypotension and inflammation. This investigation is part of a study to discover new iNOS inhibitors from medicinal plants using a macrophage cell culture system. Two sesquiterpenes (1 and 2) were isolated from Artemisia iwayomogi (Compositae) and were found to inhibit NO synthesis ($IC_{50} 3.64 \mu g/mL and 2.81 \mu$g/mL, respectively) in lipopolysaccharide (LPS)-activated RAW 264.7 cells. Their structures were identified as 3-Ο-methyl-iso-secotanapartholide (1) and iso-secotanapartholide (2). Compounds 1 and 2 inhibited the LPS-induced expression of the iNOS enzyme in the RAW 264.7 cells. The inhibition of NO production via the down regulation of iNOS expression may substantially modulate the inflammatory responses.

• Journal of Acupuncture Research
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• v.22 no.2
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• pp.111-121
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• 2005

Human placental extract (HPE), which is prepared from the placenta of healthy pregnant females, has been widely used in clinical field. HPE is known to possess anti-inflammatory, anti-viral, anti-oxidative, anti-mutagenic, and analgesic properties. In this study, the effect of HPE against lipopolysaccharide (LPS)-induced inflammation was investigated. From the present results, HPE was shown to suppress prostaglandin E2 synthesis (PGE2) and nitric oxide (NO) production by inhibition on the LPS-stimulated enhancement of the cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) expressions in mouse BV2 microglial cells. These results suggest that HPE may offer a valuable mean of therapy for the treatment of brain inflammatory diseases by attenuating LPS-induced PGE2 and NO production.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.156.2-157
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• 2003

Lipopolysaccharide (LPS)-stimulated macrophages produced a large amounts of nitric oxide (NO) by inducible nitric oxide synthase (iNOS). This is an important mechanism in macrophages-induced septic shock and inflammation. In the present study, we tested a synthetic propenone compound, l-furan-2-yl-3-pyridin-2-yl-propenone (FPP-3) for its ability to inhibit the production of tumor necrosis factor-a (TNF-$\alpha$) and an inducible enzyme, iNOS, in the LPS-stimulated murine macrophage-like cell line, Raw264.7. FPP-3 consistently inhibited nitric oxide (NO) and TNF-$\alpha$ production in a dose dependent manner, with $IC_50$> values of 10.0 and 13.1 $\mu$M, respectively. (omitted)