• Title/Summary/Keyword: COX-2

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Effect of Aspirin on the Acute Lung Injury Induced by Intestinal Ischemia/Reperfusion. (장의 허혈-재관류로 유도된 급성 폐손상에서 아스피린의 작용)

  • Park, Yoon-Yub
    • Journal of Life Science
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    • v.19 no.6
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    • pp.818-824
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    • 2009
  • The mechanisms responsible for ischemia/reperfusion (I/R) injury have direct or indirect relevance to clinical lung injury after severe shock, cardiopulmonary bypass, and transplantation. This study investigated the effects of aspirin on intestinal I/R-induced acute lung injury (ALI) in rats. Lipopolysaccharide (LPS) induced cyclooxygenase-2 (COX-2) expression in A549 and RAW264.7 cells. RAW264.7 macrophages had shown greater expression of COX-2 than A549 cells. In addition, the NADPH oxidase inhibitor apocynin and p38 MAPK inhibitor SB203580 attenuated LPS-stimulated COX-2 expression. To induce ALI, intestinal ischemia was performed for 60 min prior to the 4 hr reperfusion by clamping the superior mesenteric artery in Sprague-Dawley rats. In order to test and compare the effect of non-specific COX inhibitor aspirin with the effect of mepacrine, a well known phospholipase$A_{2}$ inhibitor, rats were divided into 4 groups: Sham, I/R, Mepa+I/R (mepacrine, 60 mg/kg, i.p.), ASA+I/R (aspirin, 10 mg/kg, i.p.). In the present investigation, myeloperoxidase activities in the lung and intestinal tissues were increased by I/R. These changes were reduced by single pretreatment of mepacrine (60 mg/kg, i.p.) or aspirin (10 mg/kg, i.p.) 30 min before I/R. Structural studies demonstrated that the tissue injuries in the lung and intestine after I/R were also attenuated by the pretreatment of mepacrine or aspirin. These results suggest that I/R-induced ALI is mediated, in part, by the activation of COX. In addition, pretreatment of aspirin might be helpful for the prevention of ALI in ARDS-prone patients. In addition, the p38 MAPK inhibitor and apocynin also might be helpful to ALI through the inhibition of COX-2 expression.

EFFECTS OF ISOTHIAZOLE AND ISOXAZOLE DERIVATIVES AS SELECTIVE CYCLOOXYGENASE-2 INHIBITORS

  • Ryu, Hyung-Chul;Park, Sang-Wook;Noh, Ji-Young;Kim, Jong-Hoon;Park, Hyun-Jung;Chung, Young-Mee;Chae, Myeong-Yun;Cho, Il-Hwan
    • Proceedings of the PSK Conference
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    • 2002.10a
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    • pp.355.3-356
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    • 2002
  • Prostaglandins are synthesized by the enzyme cyclooxygenase (COX). Both constitutive (COX-1) and inducible (COX-2) isoforms have been identified. COX-2 expression is stimulated by inflammatory mediators such as growth factors and cytokines. Most non-steroidal anti-inflammatory drugs (NSAIDS) inhibit both isoforms of COX. Recent evidence suggests that selective inhibitors of COX-2 may possess diminished side effects reletive to common NSAIDS. Novel isothiazoles and isoxazoles were identified as selective inhibitiors of cycloxygenase-2(COX-2). (omitted)

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Effects of Doche-tang on Colonic Mucosal Ulcer Induced by DSS in Mice (DSS으로 유발된 생쥐의 대장점막손상에 대한 도체탕(導滯湯)의 효과)

  • Lee, Ju-Ah;Kong, Kyung-Hwan
    • The Journal of Internal Korean Medicine
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    • v.29 no.3
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    • pp.752-764
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    • 2008
  • Objectives : This study was carried out to investigate the effects of Doche-tang on colonic mucosal ulcer induced by dextran sulfate sodium(DSS). Method : The group was divided into three. The normal group consisted of mice that were not inflammation-induced. The control group was composed of untreated colitis elicited mice. The sample group was administered Doche-tang after colitis elicitation. The effects on colonic mucosal ulcers were evaluated by the morphological change of colonic mucosa, the anti-oxidant effect, HSP 70, $NF-{\kappa}B$, COX-1, COX-2 and iNOS. Results : In terms of immunohistochemical findings, the distribution of COX-1 in mice treated with Doche-tang noticeably increased more than that in the control group. The distribution of HSP70, $NF-{\kappa}B$, COX-2, iNOS in mioe treated with Doche-tang decreased more than that in the control group. Regeneration of surface epithelial cell and goblet cell in mucosa was observed by transmission electron microscope. Conclusion : According to the results, Doche-tang is practicable treatment for colonic mucosal ulcer.

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Role of Alveolar Macrophages in Productions of Prostaglandin D2 and E2 in the Inflamed Lung (프로스타글란딘 D2와 E2의 생성에 대한 허파 마크로파이지의 역할)

  • Joo, Myung-Soo
    • Journal of Life Science
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    • v.20 no.6
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    • pp.845-852
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    • 2010
  • Our previous study showed that lungs infected by Pseudomonas, a gram-negative bacteria, produce prostaglandin $D_2$ ($PGD_2$) and prostaglandin $E_2$ ($PGE_2$), the two major prostanoids generated by cyclooxygenase-2 (COX-2), and that the ratio of $PGD_2$ and $PGE_2$ can affect the outcome of the bacterial lung infection. In this study, we sought to uncover the mechanism that determines the ratio of $PGD_2$ and $PGE_2$ produced in lung inflammation. When treated with lipopolysaccharide (LPS), primary alveolar macrophages, extracted from mouse lung, more $PGE_2$ was produced than $PGD_2$, whereas MH-S, a murine alveolar macrophage cell line, produced more $PGD_2$ than $PGE_2$ in a similar experiment. Western blot analyses showed that the kinetics of COX-2 expression in both cell types is similar and epigenetic silencing of COX-2 expression did not affect expressions of lipocalin-PGD synthase (L-PGDS) and PGE synthase (mPGES-1), major enzymes synthesizing $PGD_2$ and $PGE_2$ in inflammation, respectively, indicating no effect of COX-2 on expressions of the two enzymes. Expressions of L-PGDS and mPGES-1 were also similar in both cell types, suggesting no effect of the two key enzymes in determining the ratio of $PGD_2$ and $PGE_2$ in these cells. A single intraperitoneal injection of LPS to C57BL/6 mice induced COX-2 expression and, similar to alveolar macrophages, produced more $PGE_2$ than $PGD_2$ in the lung. These results suggest that the differential expressions of $PGD_2$ and $PGE_2$ in the lung reflect those in alveolar macrophages and may not be directly determined by the enzymes responsible for $PGD_2$ and $PGE_2$ synthesis.

Thymoquinone (TQ) regulates cyclooxygenase-2 expression and prostaglandin E2 production through PI3kinase (PI3K)/p38 kinase pathway in human breast cancer cell line, MDA-MB-231

  • Yu, Seon-Mi;Kim, Song-Ja
    • Animal cells and systems
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    • v.16 no.4
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    • pp.274-279
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    • 2012
  • Thymoquinone (TQ), a drug extracted from the black seeds of Nigella sativa, has been shown to exhibit anti-inflammatory, anti-oxidant, and anti-neoplastic effects in numerous cancer cells. The effects of TQ on cyclooxygenase-2 (COX-2) expression and prostaglandin $E_2$ ($PGE_2$) production in MDA-MB-231, however, remain poorly understood. Western blot analysis and immunofluorescence staining were performed to study the expression levels of inflammation regulatory proteins in MDA-MB-231. $PGE_2$ assay was conducted to explore the TQ-induced production of $PGE_2$. In this study, we investigated the effects of TQ on COX-2 expression and $PGE_2$ production in MDA-MB-231. TQ significantly induced COX-2 expression and increased $PGE_2$ production in a dose-dependent manner, as determined by a Western blot analysis and $PGE_2$ assay. Furthermore, the activation of Akt and p38 kinase, respectively, was up-regulated in TQ treated cells. Inhibition of p38 kinase with SB203580 and PI3kinase (PI3K) with LY294002 abolished TQ-caused COX-2 expression and decreased $PGE_2$ production. These results collectively demonstrate that TQ effectively modulates COX-2 expression and $PGE_2$ production via PI3K and p38 kinase pathways in the human breast cancer cell line MDA-MB-231.

Potentiation of Lipopolysaccharide-Inducible COX-2 Expression by C2-ceramide: The Role of JNK- and AP-1-Mediated C/EBP$\beta$ Activation

  • Cho, Yang-Hee;Lee, Chang-Ho;Kim, Sang-Geon
    • Proceedings of the Korean Society of Toxicology Conference
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    • 2002.11b
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    • pp.144-144
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    • 2002
  • Ceramide, formed by sphingomyelinase, is involved in the expression of cyclooxygenase-2 (COX-2). This study examines the effect of C2-ceramide (C2), a cell-permeable ceramide analog, on the LPS-inducible COX-2 expression and signaling pathways.(omitted)

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Synthesis and COX-2 Inhibitory Activities of Rutaecarpine Homologues

  • Jung, He-Jin;Kim, Seung-Il;Chang, Hyeun-Wook;Jahng, Yurng-Dong
    • Proceedings of the PSK Conference
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    • 2003.04a
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    • pp.250.2-250.2
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    • 2003
  • A series of rutaecarpine homologues were prepared from 2,3-polymethylene-4(3H-quinazolinones in 4 steps [i) PhCHO/Ac$_2$O, ⅱ) O,$_3$ ⅲ) PhNHNH$_2$HCl, and ⅳ) PPA], in which dihedral angles of the two planar aromatic rings (indole and 4(3H)-quinazolinone) were controlled in a regular fashion. Their inhibitory activities on COX-1 and COX-2 were evaluated to show that the inhibitory activities were increased with the increase of the length of methylene unit while selectivities on COX-2 decreased leading a loss in trimethylene bridged system.

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Studies on the Cytoprotective and Anti-inflammatory Effects of Isolate from Galla Rhois (오배자의 생리활성 연구)

  • Kim, Bo-Mi;Kwon, Tea-Ho;Chai, Kyu-Yun
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.22 no.6
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    • pp.1449-1453
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    • 2008
  • Galla Rhois is a nest of parasitic bug, has been traditionally used for the treatment of the therapy of diarrhea, peptic ulcer, hemauria, etc., that showed various anti-inflammatory activity, and other biological properties. We studied the effect of Galla Rhois ethanol extract. we investigated whether compounds isolated from the ethanol extract of Galla Rhois, could modulate iNOS and COX-2 expression in RAW 264.7 macrophages stimulated with lipopolysaccharide (LPS). We found compounds that suppressed LPS-induced iNOS and COX-2 expression. Suppression of the expression of iNOS and COX-2 was in parallel with the comparable inhibition of the production of nitric oxide (NO) and prostaglandin E2 (PGE2). Our results suggest that compounds can inhibit NO and PGE2 productions through suppression of LPS-induced iNOS and COX-2 expression. Because COX-2- or iNOS-dependent mechanisms are involved in inflammation and tumor progression, our findings provide a new uncovering mechanism responsible for anti-inflammatory and antitumor effects of Galla Rhois.

Inhibition of LPS-induced iNOS, COX-2 Expression and Cytokines Production by Fupenjic Acid in Macrophage Cells (Fupenjic Acid의 대식세포에서 LPS에 의해 유도되는 iNOS와 COX-2 발현 및 Cytokine들의 생성 저해 효과)

  • Yun, Chang-Hyeon;Shin, Ji-Sun;Park, Hee-Juhn;Park, Jong-Hee;Lee, Kyung-Tae
    • Korean Journal of Pharmacognosy
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    • v.41 no.1
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    • pp.14-20
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    • 2010
  • In this study, we investigated the anti-inflammatory effects of fupenjic acid (FA) isolated from the Potentilla discolor in both RAW 264.7 and mouse primary peritoneal macrophage cells. FA pretreatment significantly inhibited nitric oxide (NO) and prostaglandin $E_2(PGE_2)$ productions in the lipopolysaccharide (LPS)-induced RAW 264.7 and mouse primary peritoneal macrophage cells. Consistent with these observations, Western blot and RT-PCR analyses revealed that FA inhibited the LPS-induced expressions of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) at the protein and mRNA levels. In addition, FA reduced the release of tumor necrosis factor-$\alpha$ (TNF-$\alpha$) and interleukin-6 (IL-6). These results suggest that the down regulation of iNOS and COX-2 expression and TNF-$\alpha$ and IL-6 production by fupenjic acid are responsible for its anti-inflammatory effects.

COX-2 Inhibition and Anti-inflammatory Effects of Traditional Herbal Medicine (한약재의 COX-2 저해 효과와 항염증작용)

  • Kim, Yun-Kyung;Ha, Hye-Kyung;Lee, Je-Hyun;KIm, Chung-Sook
    • Korean Journal of Oriental Medicine
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    • v.8 no.1
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    • pp.65-74
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    • 2002
  • Inflammation is a disease that continues to afflict large numbers of people and may cause other diseases, for example, rheumatoid arthritis, colon cancer, etc. prostaglandins(PGs), one of arachidonic acid metabolites, are major chemical mediators in the process of inflammation. In traditional herbal medicine, many kinds of herbal drugs have been widely used for the treatment of inflammation. So, we analyzed many publications until 2001 which worked on inhibition of $PGE_2$ synthesis by cyclooxygenase-2 (COX-2) with herbs and herb oriented single compounds. And then we tried to make interpretations of herbal traditional prescriptions for inflammation. There are significant correlations between herbal medicine prescribed and inhibitions of COX-2 activity. From our efforts and further researches, we expect to develop new-inflammatory herbal drugs which have more efficacy and fewer side effects.

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