• Title/Summary/Keyword: Nitric oxide reduction

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Effect of Arsenic on Acetylcholine-Induced Relaxation in Blood Vessels in vitro cad in vivo

  • Lee, M.Y.;Chung, S.M.;Bae, O.N.;Chung, J.H.
    • Proceedings of the Korean Society of Food Hygiene and Safety Conference
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    • 2002.05a
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    • pp.137-137
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    • 2002
  • Several epidemiologidal studies suggested that arsenic exposure was strongly correlated with the development of cardiovascular disease such as hypertension. In order to examine whether arsenic affects vasomotor tone in blood vessels, we investigated the effect of arsenic on agonist-induced vasorelaxation using the isolated rat aortic ring in in vitro organ bath system. Treatment with arsenite inhibited acetylcholine-induced relaxation of aortic rings in a concentration- dependent manner. The inhibitory effects by arsenic were also observed in the relaxation induced by sodium nitroprusside, a NO-donor. Consistent with these findings, the cGMP levels stimulated by acetylcholine in blood vessels were reduced significantly by arsenite treatment. In addition, higher concentration of arsenite decreased the relaxation by 8-Br-cGMP, a cGMP analog, in aortic rings without endothelium. These in vitro results indicated that arsenite that arsenite was capable of suppressing acetylcholine-induced relaxation in blood vessels by inhibiting production of nitric oxide in endothelial cells and by impairing the relaxation machinary in smooth muscle cells. In vivo studies revealed that the reduction of blood pressure by acetylcholine infusion was signigicantly suppressed after arsenite was administered intravenously to rate. These data suggest that vasomotor tone impaired by arsenite exposure may be one of the contrbuting factors in development of cardiovascular disease.

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The Effect of Hybrid Reburning on NOx Reduction in Oxygen-Enriched LPG Flame (산소부화 LPG 화염에서 혼합형 재연소 방법에 의한 NOx 저감 효과)

  • Lee, Chang-Yeop;Baek, Seung-Wook
    • Journal of the Korean Society of Combustion
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    • v.12 no.4
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    • pp.14-21
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    • 2007
  • In order to enhance combustion efficiency, oxygen-enriched combustion is used by increasing the oxygen ratio in the oxidizer. However, since the flame temperature increases, NOx formation in the furnace seriously increases for low oxygen enrichment ratio. In this case, reburning is a useful technology for reducing nitric oxide. In this research, experimental studies have been conducted to evaluate the hybrid effects of reburning/selective non-catalytic reaction (SNCR) and reburning/air staging on NOx formation and also to examine heat transfer characteristics in various oxygen-enriched LPG flames. Experiments were performed in flames stabilized by a co-flow swirl burner, which were mounted at the bottom of the furnace. Tests were conducted using LPG gas as main fuel and also as reburn fuel. The paper reported data on flue gas emissions, temperature distribution in furnace and various heat fluxes at the wall for a wide range of experimental conditions. Overall temperature in the furnace, heat fluxes to the wall and NOx generation were observed to increase by low level oxygen-enriched combustion, but due to its hybrid effects of reburning, SNCR and Air staging, NOx concentration in the exhaust have decreased considerably.

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Lactobacillus sakei S1 Improves Colitis Induced by 2,4,6-Trinitrobenzene Sulfonic Acid by the Inhibition of NF-κB Signaling in Mice

  • Jang, Se-Eun;Min, Sung-Won
    • Journal of Microbiology and Biotechnology
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    • v.30 no.1
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    • pp.71-78
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    • 2020
  • Lactobacillus sakei S1 strongly inhibits the expression of interleukin (IL)-6 and IL-1β in lipopolysaccharide-induced peritoneal macrophages by a mechanism for which lactic acid bacteria from kimchi that inhibit tumor necrosis factor-alpha (TNF-α) were isolated. Therefore, we further evaluated the protective effect of this strain on the colitis mouse model induced by 2,4,6-trinitrobenzene sulfonic acid (TNBS). TNBS significantly elevated myeloperoxidase (MPO) expression, macroscopic scores, and colon shortening. Oral L. sakei S1 administration resulted in reduction of TNBS-induced loss in body weight, colon shortening, MPO activity, expression of cyclooxygenase (COX)-2, inducible nitric oxide synthase (iNOS) and nuclear factor-kappa B (NF-κB). L. sakei S1 inhibited the expression of inflammatory cytokines IL-1β, IL-6 and TNF-α, induced by TNBS, but enhanced IL-10 expression. L. sakei S1 showed resistance to artificial digestive juices and adherence to intestinal epithelial Caco-2 cells. Thus, L. sakei S1 may inhibit the NF-κB pathway and be used in functional food to treat colitis.

Effect of Zibachunggan-tang on lipopolysaccharide-induced expression of NF-kB downstream genes in HepG2 cell (자발 '청간탕'이 HepG2 cell의 염증반응에 대한 연구)

  • Hong Sang Hoon;Choi Byung Tae;Lee Yong Tae
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.17 no.5
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    • pp.1251-1256
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    • 2003
  • To determine the effect of Zibachunggan-tang(ZCT) on the process of lipopolysaccharide (LPS)-induced nuclear factor-kBp65 (NF-kBp65) activation, and LPS-induced expression of pro-inflammatory proteins including tumor necrosis factor-α (TNF-α), nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), in HepG2 cell. Immunoblot analysis showed that the level of nucleic NF-kBp65 was rapidly up-regulated and cytosolic inhibitory I-kBα was down-regulated by LPS challenge. While ZCT inhibited an increase of NF-kBp65 and degradation of I-kBα in HepG2 cell. Beside LPS-induced expression of a group of genes, such as TNF-α, inducible iNOS and COX-2, are repressed by ZCT. It may be concluded that ZCT attenuates the progress of LPS-induced inflammation by reduction of NF-kBp65 activation. The ZCT would be useful as a therapeutic agent for endotoxin-induced liver disease.

In vivo ESR measurement of free radical reaction in living mice

  • Han, Jin-Yi;Hideo Utsumi
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 2000.04a
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    • pp.6-7
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    • 2000
  • Recently, free radicals such as active oxygen species, nitric oxide, etc are believed to be one of the key substances in physiological and pathological, toxicological phenomena, and oxidative damages, and all organism have defencing system against such as free radicals. Formation and extinction of free radicals may be regulated through bio-redox system, in which various enzymes and compounds should be involved in very complicated manner. Thus, direct and non-invasive measurement of in vivo free radical reactions with living animals must be essential to understand the role of free radicals in pathophysiological phenomena. Electron spin resonance spectroscopy (ESR) is very selective and sensitive technique to detect free radicals, but a conventional ESR spectrometer has large detect in application to living animals, since high frequent microwave is absorbed with water, resulting in generation of high fever in living body. In order to estimate in vivo free radical reactions in living whole animals, we develop in vivo ESR-CT technique using nitroxide radicals as spin probes. Nitroxide radicals and their reduced forms, hydroxylamines, are known to interact with various redox systems. We found that! ! the signal decay due to reduction of nitroxyl radicals is influenced by aging, inspired oxygen concentration, ischemia-referfusion injury, radiation, etc. In the present paper, I will introduce in vivo ESR technique and my laboratory recent results concerning non-invasive evaluation of free radical reactions in living mice.

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Prior Use of 3-Hydroxy-3-Methyl-Glutaryl-Coenzyme A Reductase Inhibitor, Simvastatin Fails to Improve Outcome after Experimental Intracerebral Hemorrhage

  • Jwa, Cheol-Su;Yi, Hyeong-Joong;Oh, Suck-Jun;Hwang, Se-Jin
    • Journal of Korean Neurosurgical Society
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    • v.50 no.5
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    • pp.403-408
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    • 2011
  • Objective : Contrary to some clinical belief, there were quite a few studies regarding animal models of intracerebral hemorrhage (ICH) $in$ $vivo$ suggesting that prior use of statins may improve outcome after ICH. This study reports the effect of 3-hydroxy-3-methyl-glutaryl-coenzyme A (HMG CoA) reductase inhibitor, simvastatin given before experimental ICH. Methods : Fifty-one rats were subjected to collagenase-induced ICH, subdivided in 3 groups according to simvastatin treatment modality, and behavioral tests were done. Hematoma volume, brain water content and hemispheric atrophy were analyzed. Immunohistochemical staining for microglia (OX-42) and endothelial nitric oxide synthase (eNOS) was performed and caspase-3 activity was also measured. Results : Pre-simvastatin therapy decreased inflammatory reaction and perihematomal cell death, but resulted in no significant reduction of brain edema and no eNOS expression in the perihematomal region. Finally, prior use of simvastatin showed less significant improvement of neurological outcome after experimental ICH when compared to post-simvastatin therapy. Conclusion : The present study suggests that statins therapy after ICH improves neurological outcome, but prior use of statins before ICH might provide only histological improvement, providing no significant impact on neurological outcome against ICH.

Evaluation of the Nitrate Anion in Recon Extract by Adsorbents

  • Han, Young-Rim;Sung, Yang-Joo;Park, Jin-Won;Kim, Yang-Ok;Rhee, Moan-Soo
    • Journal of the Korean Society of Tobacco Science
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    • v.29 no.2
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    • pp.104-109
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    • 2007
  • The amount of nitrate in the tobacco leaf has been shown to be correlated with the levels of alkaloids and nitrosamines. Also the nitrate content of the tobacco correlated closely with the smoke delivery of nitric oxide and tobacco-specific nitrosamines (TSNAs). These are related with the effect of the reconstituted tobacco leaf(Recon) using the tobacco stems. Adsorption process is gaining interest as one of the effective processes of advanced liquid treatment for liquid containing unnecessary materials. This study is focused on the evaluation of four anion exchangers, a cation exchanger and an activated carbon, as adsorbents for reduction of nitrate anion from Recon extract. In order to analyze the nitrate anion, the IC method used in this work was carried out with a Dionex ICS-2000 system. The effects of dosages of adsorbents and concentration of extract on the removal of nitrate anion were examined. Experimental results showed that for nitrate-anion exchanger, nitrate-cation exchanger and nitrate-activated carbon adsorption system, approximately 70 %, 10 %, and 4 % removal efficiencies were achieved at the Brix 10 and the 20 % addition. Although the activated carbon was little efficient for removal of nitrate ion, the removal of nicotine was very efficient at given conditions.

The Effects of Platycodi Radix on the Induction of LPS and the Activation of $NF-{\kappa}Bp$, the Lung Disease of White Rats

  • Kim Hyun-Joong;Park Dong-Il;Kim Won-Il
    • The Journal of Korean Medicine
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    • v.26 no.1 s.61
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    • pp.18-25
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    • 2005
  • Objective & Methods: We examined the effects of Platycodi radix on the process of lipopolysaccharide (LPS)-induced nuclear factor $NF-{\kappa}Bp65$ and inhibitory $(I)-{\kappa}B{\alpha}$ alteration in RAW 264.7 cells and acute lung injury in rats. Results: Immunoblot analysis showed that LPS-induced degradation of $I-{\kappa}B{\alpha}$ in RAW 264.7 was inhibited by pretreatment of Platycodi radix. The total cells of bronchoalveolar lavage fluid by LPS challenge markedly decreased in the Platycodi radix pretreatment rats. Platycodi radix pretreatment also caused a decline in neutrophils infiltration into interstitium of the lung. In the alveolar macrophages and neutrophils, decreased $NF-{\kappa}Bp65$ and inducible nitric oxide synthase and increased $I-{\kappa}B{\alpha}$ immunoreaction were detected in Platycodi radix pretreated rats compared with LPS alone treated ones. Conclusion : It may be concluded that Platycodi radix attenuates the development of LPS-induced inflammation by reduction of $NF-{\kappa}Bp65$ activation and neutrophil-mediated acute lung injury. Platycodi radix would be useful as a therapeutic agent for endotoxin-induced lung disease.

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Identification of 1-Furan-2-yl-3-pyridin-2-yl-propenone, an Anti-inflammatory Agent, and Its Metabolites in Rat Liver Subcellular Fractions

  • Lee, Sang-Kyu;Jeon, Tae-Won;Basnet, Arjun;Jeong, Hye-Gwang;Lee, Eung-Seok;Jeong, Tae-Cheon
    • Archives of Pharmacal Research
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    • v.29 no.11
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    • pp.984-989
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    • 2006
  • 1-Furan-2-yl-3-pyridin-2-yl-propenone (FPP-3) has been characterized to have an anti-inflammatory activity through the inhibition of the production of nitric oxide and tumor necrosis $factor-{\alpha}$. In the present studies, the phase 1 metabolism of FPP-3 was investigated in rat liver microsomes and cytosols. When FPP-3 was incubated with rat liver microsomes and cytosols in the presence of NADPH. 2 major peaks were detected on a liquid chromatography/electrospray ionization-mass spectrometry. Two metabolites (i.e., M1 and M2) were characterized as reduced forms on propenone: M1 (1-furan-2-yl-3-pyridin-2-yl-propan-1-one) was the initial metabolite and M2 (1-furan-2-yl-3-pyridin-2-yl-propan-1-ol) was a secondary alcohol believed to be formed from M1.

Kamgil-Tang attenuates lipopolysaccharide-induced NF-${\kappa}$B activation in RAW 264.7 cell and acute lung injury in rats

  • Park, Dong-Il;Kim, Do-Hyun;Choi, Byung-Tae
    • Journal of Life Science
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    • v.10 no.2
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    • pp.55-60
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    • 2000
  • We examined the effects of Kamgil-Tang on the process of lipopolysaccharide (LPS)-induced unclear factor (NF)-${\kappa}$ Bp65 and inhibitory (I)-${\kappa}$ B${\alpha}$ alteration in RAW 264.7 cell and acute lung injury in rats. Immunoblot analysis showed that LPS-induced degradation of I-${\kappa}$ B${\alpha}$ in RAW 264.7 was inhibited by pretreatment of Kamgil-Tang. The total cells of bronchoalveolar lavage fluid by LPS challenge markedly decreased in the Kamgil-Tang pretreatment rats. Kamgil-Tang pretreatment caused also a decline in neutrophils infiltration into interstitium of the lung. In the alveolar macrophages and neutrophils, decreased NF-${\kappa}$ Bp65 and inducible nitric oxide synthase and increased I-${\kappa}$ B${\alpha}$ immunoreaction were detected in Kamgil-Tang pretreated rats compared with LPS alone treated ones. It may be concluded that Kamgil-Tang attenuates the development of LPS-induced inflammation by reduction of NF-${\kappa}$ Bp65 activation and neutrophil-mediated acute lung injury. Kamgil-Tang would be useful as a therapeutic agent for endotoxin-induced lung disease.

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