• Title/Summary/Keyword: iNOS inhibitor

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Radiation-Induced Proctitis in Rat and Role of Nitric Oxide (백서모델에서 방사선 직장염 유발인자로서의 Nitric oxide의 역할)

  • Chun Mison;Kang Seunghee;Jin Yoon-Mi;Oh Young-Taek;Kil Hoon-Jong;Oh Tae-Young;Ahn Byoung-Ok
    • Radiation Oncology Journal
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    • v.19 no.3
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    • pp.265-274
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    • 2001
  • Purpose : Proctitis is one of acute complications encountered when radiotherapy was appled to the pelvis. Radiation-induced proctitis represents similar microscopic findings that are observed in inflammatory bowel disease (IBD). Nitric oxide (NO) plays an important role in the inflammatory process and many data suggest a close relationship between NO production and gastrointestinal inflammation. This study was aimed to establish the optimal radiation dose for radiation-induced proctitis in rat and to find a relationship between radiation proctitis and NO production. Materials and methods : Female Wistar rats, weighing from 150 to 220 g, received various doses(10-30 Gy) of radiation to the rectum. On the 5th and 10th day after irradiation, rectal specimens were evaluated grossly and microscopically. In addition, the degree of NO production by irradiation dose was evaluated by study with NOS expression and nitrite production in the irradiated rectal tissue. To evaluate relationship between radiation proctitis and NO, we administered aminoguanidine, iNOS inhibitor and L-arginine, substrate of NOS to rats from 2 days before to 7 days after the irradiation. Results : There were obvious gross and hostological changes after 17.5 Gy or higher radiation dose but not with 15 Gy or less radiation dose. Twenty Gy or higher dose of radiation caused Grade 4 damage in most of rectal specimens which were more likely to be related to the late complications such as fibrosis, rectal bleeding and rectal obstruction. A single fraction of 17.5 Gy to the rat rectum is considered to be an optimal dose to produce commonly experienced proctitis in the clinic. The result demonstrated that severity of microscopic damage of rectal mucosa from irradiation significantly correlated with iNOS over-expression. However, administration of iNOS inhibitor or substrate of iNOS did not influence the degree of rectal damage. Conclusion : A single fraction of 17.5 Gy irradiation to the rat rectum considered to be an optimal dose for radiation induced proctitis model. These results indicated that an excess production of NO contributes to pathogenesis of radiation-induced proctitis in part but was not the direct cause of rectal damage.

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Inhibitory effect of Yongdamsagantang water extract on IL-6 and nitric oxide production in lipopolysaccharide-activated RAW 264.7 cells

  • Lim, Jin-Ho;Lee, Jong-Rok;Kim, Sang-Chan;Jee, Seon-Young
    • Advances in Traditional Medicine
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    • v.7 no.3
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    • pp.321-329
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    • 2007
  • The present study was conducted to evaluate the effect of Yongdamsagantang (YST) on the regulatory mechanism of cytokines and nitric oxide (NO) for the immunological activities in RAW 264.7 cells. After the treatment of YST water extract, cell viability was measured by MTT assay, and NO production was monitored by measuring the nitrite content in culture medium. Inducible nitric oxide synthase (iNOS) and phospholylation of inhibitor of nuclear factor kappa B alpha ($p-I{\kappa}B{\alpha}$) were determined by Immunoblot analysis, and levels of cytokine were analyzed by sandwich immunoassays. Results provided evidences that YST inhibited the production of NO. iNOS, and interleukin-6, and the activation of $p-I{\kappa}B{\alpha}$ in RAW 264.7 cells activated with lipopolysaccharide. These findings showed that YST could have some anti-inflammatory effects which might play a role in therapy in Gram-negative bacterial infections.

Effect of quercetin on the production of nitric oxide in murine macrophages stimulated with lipopolysaccharide from Prevotella intermedia

  • Cho, Yun-Jung;Kim, Sung-Jo
    • Journal of Periodontal and Implant Science
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    • v.43 no.4
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    • pp.191-197
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    • 2013
  • Purpose: Nitric oxide (NO) is a short-lived bioactive molecule that is known to play an important role in the pathogenesis of periodontal disease. In the current study, we investigated the effect of the flavonoid quercetin on the production of NO in murine macrophages activated with lipopolysaccharide (LPS) from Prevotella intermedia, a pathogen related to inflammatory periodontal disease, and tried to elucidate the underlying mechanisms of action. Methods: LPS was isolated from P. intermedia ATCC 25611 cells by the standard hot phenol-water method. The concentration of NO in cell culture supernatants was determined by measuring the accumulation of nitrite. Inducible NO synthase (iNOS) and heme oxygenase-1 (HO-1) protein expression, phosphorylation of c-Jun N-terminal kinase (JNK) and p38, inhibitory ${\kappa}B$ $(I{\kappa}B)-{\alpha}$ degradation, and signal transducer and activator of transcription 1 (STAT1) phosphorylation were analyzed via immunoblotting. Results: Quercetin significantly attenuated iNOS-derived NO production in RAW246.7 cells activated by P. intermedia LPS. In addition, quercetin induced HO-1 protein expression in cells activated with P. intermedia LPS. Tin protoporphyrin IX (SnPP), a competitive inhibitor of HO-1, abolished the inhibitory effect of quercetin on LPS-induced NO production. Quercetin did not affect the phosphorylation of JNK and p38 induced by P. intermedia LPS. The degradation of $I{\kappa}B-{\alpha}$ induced by P. intermedia LPS was inhibited when the cells were treated with quercetin. Quercetin also inhibited LPS-induced STAT1 signaling. Conclusions: Quercetin significantly inhibits iNOS-derived NO production in murine macrophages activated by P. intermedia LPS via anti-inflammatory HO-1 induction and inhibition of the nuclear factor-${\kappa}B$ and STAT1 signaling pathways. Our study suggests that quercetin may contribute to the modulation of host-destructive responses mediated by NO and appears to have potential as a novel therapeutic agent for treating inflammatory periodontal disease.

Effect of $N^G$-nitro-L-arginine methyl ester and Methylene Blue on the Endotoxin-induced Vascular Hyporesponsiveness (세균 내독소 유발 혈관 저반응성에 대한 $N^G$-nitro-L-arginine methyl ester와 Methylene blue의 영향)

  • Choi, Hyoung-Chul;Ha, Jeoung-Hee;Lee, Kwang-Youn;Kim, Won-Joon;Sohn, Uy-Dong
    • Journal of Yeungnam Medical Science
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    • v.14 no.2
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    • pp.337-349
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    • 1997
  • This study was undertaken to examine the intensity of involvement of inducible nitric oxide synthase (iNOS) and cyclic GMP signal transduction pathway as one of the mechanisms of vaso-relaxative action of bacterial lipopolysaccharide (LPS) on the canine femoral artery strips. Canine femoral arteries were isolated and spiral strips of 10 mm long and 2 mm wide were made in the Tyrode solution of $0-4^{\circ}C$. The strips were prepared for isometric myography in Biancani's isolated muscle chamber containing 1 ml of Tyrode solution, which was maintained with pH 7.4 by aeration with 95% $O_2$/5% $CO_2$ at $37^{\circ}C$ and nitric oxide (NO) production was measured simulltaneously with isolated nitric oxide meter. LPS induced NO production, suppressed the phenylephrine (PE) induced contraction and enhanced the acetylcholine (ACh) induced relaxation. $N^G$-nitro-L-arginine methyl ester (L-NAME), an NOS inhibitor, methylene blue, a guanylyl cyclase inhibitor, potentiated PE induced contraction and suppressed ACh induced relaxation on the LPS treated strips. The inhibitory potency of methylene blue for LPS induced vascular hyporesponsiveness was stronger than that of L-NAME. These results suggest that in canine femoral artery, both iNOS and cyclic GMP signal trnasduction pathway are related with LPS induced vascular hyporeponsiveness, but in minor with iNOS and in major with cyclic GMP signal trnasduction pathway.

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Effects of γ-Aminobutyric Acid (GABA)-Enriched Sea Tangle Laminaria japonica Extract on Lipopolysaccharide-Induced Inflammation in Mouse Macrophage (RAW 264.7) Cells

  • Choi, Ji-Il;Yun, In-Hye;Jung, Yeounjoong;Lee, Eun-Hye;Nam, Taek-Jeong;Kim, Young-Mog
    • Fisheries and Aquatic Sciences
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    • v.15 no.4
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    • pp.293-297
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    • 2012
  • ${\gamma}$-Aminobutyric acid-enriched sea tangle extract was obtained from the fermentation of Lactobacillus brevis BJ-20. The fermented sea tangle extract (FST) was separated into three fractions by molecular weight: FST I (greater than 10 kDa), FST II (1-10 kDa), and FST III (less than 1 kDa). The anti-inflammatory characteristics of the FST fractions were investigated by measuring the production of nitric oxide (NO) and the expression levels of inducible nitric oxide synthase (iNOS) in lipopolysaccharide (LPS)-induced mouse macrophage (RAW 264.7) cells. Both NO production and iNOS expression levels were significantly inhibited by FST treatments in a dose-dependent manner. FST III was the most effective inhibitor of processes. This demonstrates that the effect of FST on LPS-induced inflammation might be closely correlated with the inhibition of inflammatory cytokine expression.

Effect of nitric oxide on the cyplal gene expression

  • Kim, Ji E.;Jung Y. Bae;Yhun Y. Sheen
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 1998.11a
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    • pp.141-141
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    • 1998
  • In order to study the effect of nitric oxide on the regulation of mouse cyplal expression, 5' flanking DNA of mouse cytochrome P450 lal was cloned into pGL3 basic vector encoding luciferase gene. pcyplal-Luc was transfected into Hepa I cells and various chemicals were treated. Luciferase activity was stimulated 1000 folds over that of control by TCDD (2,3,7,8-tetrachloro-p-dioxin) treatment and this stimulation was dose dependent. When SNP (sodium nitroprusside) which donates nitric oxide was administrated, this stimulatory effect of TCDD on luciferase activity was decreased. And LPS (lipopolysaccharide) which is an iNOS (inducible nitric oxide synthase) inducer also decreased the stimulatory effect of TCDD on luciferase. And iNOS inhibitor N$\^$G/-nitro-ι-arginine + TCDD treatment increased the stimulation effect of TCDD and this effect was abolished when ι-arginine was added to N$\^$G/-nitro-ι-arginine + TCDD treatment. When N$\^$G/-nitro-ι-arginine was concomitantly administrated with SNP or LPS to confirm the effect of nitric oxide, the inhibitory effect of SNP or LPS was abolished. These data strongly suggest that nitric oxide might be an inhibitory regulator on the cytochrome P450 lal gene expression in Hepa cells.

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Inhibitory effect of Gentianae Radix MeOH extract on pro-inflammatory mediator production in lipopolysaccharide activated Raw 264.7 cells (용담초(龍膽草) 추출물이 LPS로 활성화된 Raw 264.7 cell에서의 pro-inflammatory mediator에 미치는 영향)

  • Kim, Mi-Seon;Cho, Won-Joon;Hwang, Sun-Yi;Lee, Jong-Rok;Park, Sook-Jahr;Kim, Sang-Chan;Jee, Seon-Young
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.21 no.2
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    • pp.28-38
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    • 2008
  • In traditional oriental medicine, Gentianae Radix has been used clinically for clearing away 'heat', removing dampness and purging fire in the liver and gall bladder. However, there has been a lack of studies regarding the effects of Gentianae Radix on the immunological activities. The present study was conducted to evaluate the effect of Gentianae Radix on the regulatory effects of cytokines and nitric oxide(NO) for the immunological activities in Raw 264.7 cells. After the treatment of Gentianae Radix MeOH extract, cell viability was measured by MTT assay, and NO production was monitored by measuring the nitrite content in culture medium. The expression of COX-2 and iNOS was determined by immunoblot analysis, and the content of levels of cytokines in media was analyzed by ELISA kit. Results provided evidence that Gentianae Radix inhibited the production of nitrite and nitrate (NO), inducible nitric oxide synthase (iNOS), $interleukin-l{\beta}$ $(IL-l{\beta})$ and IL-6, and the activation of phospholylation of inhibitor ${\kappa}B{\alpha}$ ($p-I {\kappa}B{\alpha}$) in Raw 264.7 cells activated with lipopolysaccharide (LPS). These findings suggest that Gentianae Radix can make anti-inflammatory effect, which may playa role in adjunctive therapy.

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Inhibitory effect of Scrophulariae Radix extract on $TNF-{\alpha},\;IL-1{\beta}$, IL-6 and Nitric Oxide production in lipopolysaccharide - activated Raw 264.7 cells (현삼메탄올 추출물이 LPS로 유도된 Raw 264.7 cell에서의 $TNF-{\alpha},\;IL-1{\beta}$, IL-6, 및 nitric oxide 생성에 미치는 영향)

  • Byun, Sung-Hui;Yang, Chae-Ha;Kim, Sang-Chan
    • The Korea Journal of Herbology
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    • v.20 no.2
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    • pp.7-16
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    • 2005
  • Objectives : Scrophulariae Radix (SRE) is commonly used in combination with other herbs as a nutrient and health strengthening agent, and to remove 'heat' and replenish vital essence. The water-based extract of this herb can lower blood pressure in both anesthetized and concious animals, and exhibits an anti-inflammatory activity. But, there is lack of studies regarding the effects of SRE on the immunological activities in molecular levels. The present study was conducted to evaluate the effect of SRE on the regulatory mechanism of cytokines and nitric oxide (NO) in Raw 264.7 cells. Method : After the treatment of Scrophulariae Radix methanol extract, cell viability was measured by MTT assay, NO production was monitored by measuring the nitrite content in culture medium. COX-2 and iNOS were determined by Immunoblot analysis, and levels of cytokine were analyzed by sandwich immunoassays. Results : Results provided evidence that SRE inhibited the production of nitrite and nitrate (NO), inducible nitric oxide synthase (iNOS), $interleukin-1{\beta}\;(IL-1{\beta})$ and interleukin-6 (IL-6), and the activation of phospholylation of inhibitor ${\kappa}B{\alpha}\;(p-I{\kappa}B{\alpha})$ in Raw 264.7 cells activated with lipopolysaccharide (LPS). Conclusion : These findings suggest that Scrophulariae Radix can produce anti-inflammatory effect, which may playa role in adjunctive therapy in Gram-negative bacterial infections.

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The Effects of $Hwangryunhaedok$-$tang$ Pharmacopuncture by the Anti-inflammatory Action of Suppression of iNOS Production on Mice with Allergic Rhinitis (황련해독탕 약침액의 iNOS 생성 억제를 통한 항염증효과가 알레르기성 비염 유발 생쥐의 치료에 미치는 영향)

  • Cho, Jae-Yong;Kim, Yu-Jong;Kim, Eun-Jung;Lee, Seung-Deok;Kim, Kap-Sung
    • Journal of Acupuncture Research
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    • v.29 no.1
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    • pp.89-101
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    • 2012
  • Objectives : The purpose of this study was find out the therapeutic effects of its exclusive use on the rat with allergic rhinitis. Materials and Methods : Thirty Sprague-Dawley rats were divided into three group : normal group, control group and sample group. To induce the allergic rhinitis in control group and sample group, rats were sensitized intraperitoneally with 0.1% ovalumin solution 3 times at intervals of 1 week. Then intranasal sensitization was performed by diffusing 0.1% ovalumin solution 3 times at intervals of 2 days. After that time, rats in the sample group were administered by $Yonghyang$($LI_{20}$) subcutaneously to treat the inflammation. Results : 1. The anti-oxidant effects of $Hwangryunhaedok-tang$ extract was dose-dependantly increased. 2. The RAW 264.7 cells were treated with LPS for 1 hours prior to the addition of indicated concentrations ($0.4,-1.0mg/m{\ell}$) of HHT, and the cells were further incubated for 24 hours. The LPS-induced iNOS mRNA expression and NO production were dose-dependantly decreased in HHT treated RAW 264.7 cells. 3. The number of eosinophil in HP noticeably decreased than CON and this decrease had probability. The infiltration of eosinophil in HP noticeably decreased than CON. 4. The damaged mucosa as disruption of cilia in respiratory cell and vacant mucose secreting cell were increased CON, but HP same as normal configuration. Decrease of PAS positive cell were shown in CON, but goblet cell occupied with neutral mucous were shown in HP. Decrease of mucosal stress(HSP70). Decrease of perennial sign(PPAR-${\gamma}$). Decrease of icthing and sneezing intricate neurotransmitter-(substance P). 5. The anti-inflammation of HHT pharmacopuncture for AR caused mucosa comes to result as belows. Decrease of pre-inflammation cytokine(TNF-${\alpha}$). Decrease of transcription factor (NF-${\kappa}B$ p65). Decrease of transcription factor inhibitor(p-$I{\kappa}B$). Decrease of inflammation cytokine(iNOS). Conclusions : The results may suggest that administration treatment using $Hwangryunhaedok-tang$ pharmacopucnture decreases the inflammatory response on an animal model with allergic rhinitis.

Inhibitory Effect of Chan-Su on the Secretion of PGE2 and NO in LPS-stimulated BV2 Microglial Cells

  • Kim, Min-Hee;Lyu, Ji-Hyo;Lyu, Sun-Ae;Hong, Sang-Hoon;Kim, Won-Il;Yoon, Hwa-Jung;Ko, Woo-Shin
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.22 no.5
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    • pp.1315-1321
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    • 2008
  • Chan-Su (Venenum bufonis) has long been for a variety of other purposes including treatment of inflammation in the folk medicine recipe. Since nitric oxide (NO) is one of the major inflammatory parameters, we first studied the effects of Chan-Su on NO production in lipopolysaccharide (LPS)-stimulated BV2 microglial cells, Chan-Su inhibited the secretion of NO in BV2 microglial cells, without affecting cell viability, The protein level of inducible nitric oxide synthase (iNOS) was decreased by Chan-Su, And Chan-Su also inhibited production of prostaglandin E2 (PGE2) and expression of cyclooxygenase (COX)-2. Proinflammatory cytokines, such as tumor necrosis factor $(TNF)-{\alpha}$, interleukin $(IL)-1{\beta}$ and IL-12, were inhibited by Chan-Su in a dose-dependent manner. And Chan-Su inhibited the degradation of ${IkB-\alpha}$, which was considered to be inhibitor of nuclear factor $(NF)-{\kappa}B$, one of a potential transcription factor for the expression of iNOS, COX-2 and proinflammatory cytokines. These results suggest that Chan-Su could exert its anti-inflammatory actions by suppressing the synthesis of NO through inhibition of $I{\kappa}B-{\alpha}$ degradation.