• Tuberculosis and Respiratory Diseases
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• v.39 no.4
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• pp.304-309
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• 1992

Background: The alveolar macrophage may metabolize arachidonic acid through cyclooxygenase- and lipoxygenase- catalyzed pathways to produce a variety of metabolites of arachidonic acid. The production of these metabolites of arachidonic acid may enhance the defensive ability of the challenged lung. However, continued stimulation with the consequent production of proinflammtory metabolites of arachidonic acid, may ultimately enhance the disease process by contributing to chronic bronchoconstriction, fibrosis, and the persistent release of toxic oxygen species. Silicosis is an example of a disease process resulting from chronic exposure of the lung to foreign particles. This study was carried out to evaluate the changes of arachidonic acid metabolites from macrophages in experimental silicosis. Methods: We measured $PGE_2$, and $LTB_4$ in cultured macrophages taken from rats by radioimmunoassay at 24 and 48 hours after stimulation by silica dust, natural carbon dust, lipopolysaccharide, calcium ionophore (A23187) and medium (RPMI) as a control. For the experimental silicosis, 50 mg silica in 0.5 ml saline was administered intratracheally into the rat and grown to 20 weeks and measured $PGE_2$, and $LTB_4$ in the cultured macrophages lavaged from that rat. The used stimulants were the same as above. Results: 1) The amount of $PGE_2$ in the cultred macrophages from normal rat was significantly decreased in the group which was stimulated with silica dust for 48 hours compare with control non-stimulated group. 2) In the experimental silicosis group, $PGE_2$, release in cultured macrophages after 48 hours incubation with silica and natural carbon dust tended to be lower than those of non-stimulated group. 3) There were marked changes of $LTB_4$ in the groups of normal rats which were incubated with silica for 24, 48 hours and natural carbon for 48 hours compared with non-stimulated group. 4) In the experimental silicosis group, the release of $LTB_4$ was significantly increased macrophages cultured with silica and natural carbon dust after 24 and 48 hours incubation compared with non-stimulated group. Conclusion: The results of these studies suggest that the in vitro exposure of rat alveolar macrophge to silica and coal dust results in an alteration in alveolar macrophage metabolism of arachidonic acid that may promote an inflammatory reaction in lung tissue.

• The korean journal of orthodontics
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• v.28 no.4 s.69
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• pp.611-626
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• 1998

Cytokines are intercellular peptide mediators that regulate homeostasis and host defense reactions in living body. Of the diversity of cytokines in terms of biological accomplishment, interleukin $1-{\beta}$($IL-1{\beta}$) and tumor necrosis factor(TNF) are the most conspicuous cytokines with a wide variety of effects on cells involved in inflammatory and immune responses, and likely to be involved in the inflammatory pathogenesis of oral tissue as well. The present study was designed to explicate the role of $IL-1{\beta}$ on inflammatory revelation of oral tissues in mice biochemically. In the Induced arthritis by injection of 10${\mu}g$ LPS shown the relaese of 0.93 ${\mu}g$ $IL-1{\beta}$/joint with a peak at at 4-5 h. and diminished at 24t and the release of $TNF_{\alpha}$ of 1.25 ${\mu}g$/joint with a peak at 2-3h and diminished at 6h. After injection of th $IL-1{\beta}$ into the joint, the mumber of leucocytes proliferated with a peak at 4-5h and diminished at 36h and the loss of proteoglycan showed with maximum at 15-30h. After injection of $IL-1{\beta}$ into the oral tissue, cycloosygenase metabolites ($PGE_2$) accumulated in the oral tissue with dose dependant. These elucidated $IL-1{\beta}$ to be inflammatory mediator in the early phase of its pathogenesis. Intraoral injection of recombinant $IL-1{\beta}$ induced the proliferation of leukocytes in situ. $IL-1{\beta}$ took an pertinent part in the development of inflammation and the succession of cellular infiltration. The results exemplify that $IL-1{\beta}$ plays a significant role in mediating inflammatory response induced by LPS in oral tissue, the inflammatory response is regulated by $IL-1{\beta}$ at an acute phase of pathogenesis.

• Proceedings of the Ginseng society Conference
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• 1988.08a
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• pp.77-80
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• 1988

The effects of ginseng saponins and some phenolic acids on the in vitro biosynthesis of prostaglandins was examined in order to identify the role of some ginseng components on the regulaion of arachidonic acid metabolism. The productions of prostaglandin $E_2(PGE_2).$ prostaglandin $F_2{\alpha}(PGF_2{\alpha}).$ thromboxane $B_2(TxB_2)$ and 6-keto-prostaglandin $F_1{\alpha}(6-keto-PGF_1{\alpha})$ from $[^3H]-arachidonic$ acid were evaluated with rabbit kidney microsome. human platelet homogenate and bovine aortic microsome. The amounts of the total cyclooxy-genase products from arachidonic acid did't show significant changes in the presence of ginseng saponins. Panaxadiol. panaxatriol and all of the ginsenosides used in these experiments reduced the formation of $TxB_2.$ while increased the $6-keto-PGF_1{\alpha}$ production dose dependently. Ginseng saponins did't inhibit the ADP($10{\mu}M$) induced platelet aggregation. but sodium arachidonate (0.5 mM) induced platelet aggregation. but sodium arachidonate (0.5 mM) induced platelet aggregation was signiticantly inhibited. These findings suggest that ginseng saponins seem to playa role in the regulation of the arachidonate metabolism. probably by affecting the divergent biosynthetic pathway of prostaglandins from endoperoxide.

• Journal of Applied Biological Chemistry
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• v.66
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• pp.46-52
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• 2023

The most abundant flavanone of grapefruits, naringenin (NN), is well known for its hepatoprotective, anti-lipid peroxidation and anti-carcinogenic effects. We generated three derivatives from NN using this technique in previous studies. Among them, it was confirmed that naringenin-7-O-phosphate (N7P), whose biological and physicochemical properties were not reported, showed a water solubility 45 times higher than that of NN. Therefore, in this study, the anti-inflammatory activity was evaluated in RAW 264.7 cells to investigate the potential physiological activity of N7P. As a result, N7P showed nitric oxide (NO) inhibitory activity at concentrations that did not show toxicity. In addition, prostaglandin E₂ (PGE₂) showed significant inhibitory activity from the lowest concentration of 12.5 μM and showed increased inhibitory activity compared to NN. In addition, as a result of western blot, N7P showed increased cyclooxygenase-2 (COX-2) inhibitory activity than NN, and effectively inhibited NO and PGE₂ by significantly inhibiting their expression pathways. N7P also inhibited inflammatory cytokines, including tumor necrosis factor-α, interleukin-6. Based on these results, we propose that N7P can be used as a potent antiinflammatory agent.

• Tuberculosis and Respiratory Diseases
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• v.48 no.2
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• pp.191-202
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• 2000

Background: Bronchial asthma is characterized by airway hyperresponsiveness(BHR) and inflammation. The cyclooxygenase(COX) is believed to be one of the important enzymes in these inflammatory reactions. Recently, the COX was divided into two isoforms, COX1 and COX2. COX2 is induced by lipopolysaccharide and some cytokines at the inflammation site. Prostaglandin E2(PGE2), produced from COX2, may affect airway inflammation. The purpose of this study is to evaluate the effect of COX2 inhibitor on COX2 expression, plasma PGE2, airway resistance and histologic finding in an animal asthma model. Methods : Sprague-Dawley rats were divided into 3 groups. The normal control group did not receive any treatment, but the asthma control group was sensitized by ovalbumin but not treated with the COX2 inhibitor(nimesulide, Mesulid$^{(R)}$). The treatment group was sensitized and treated with nimesulide. Specific airway resistance(sRaw) before and after nimesulide ingestion was investigated. The PGE2 level in the plasma was examined and COX2 immunogold-silver stain on lung tissue was performed. Results: sRaw and eosionophilic infiltration on airway, which increased in the asthma control group, was compared to normal control(p=0.014). However, there was no difference in eosinophilic infiltration between asthma control and treatment groups(p=0.408) and no difference in COX2 expression on bronchiolar epithelium among the three groups. Plasma PGE2 levels were not statically different among the three groups. Conclusion: The role of COX2 in the allergen-induced BHR was not significant The effect of nimesulide was not observed on BHR, COX2 expression, and plasma PGE2 level. Therefore, COX2 may not be a major substance of allergic asthma.

• Journal of Ginseng Research
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• v.13 no.2
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• pp.202-210
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• 1989

The effects of Ginseng saponins on the in vitro biosynthesis of prostaglandins were examined in order to identify the role of some Ginseng components on the regulation of arachidonic arid metabolism. The productions of prostaglandin $E_2$ (PG$E_2$), $F_2$ (PGF2), thromboxane $B_2$(TX$B_2$) and 6-ketoprostaglandin Fl (6-Keto-PGF1) from [3Hl-arachidonic acid were evaluatpf by radiochromatographic analysis with rabbit kidney microtome, human platelet homogenate and bovine aortic microsome. The amounts of the total prostaglandins produced by cyclooxygenase activity and malondialdehyde from arachidonic acid didn't show significant changes in the presence of Ginseng saponins. Both of panaxadiol and panaxatriol didn't affect the production of PG$E_2$ while the formations of PG$F_2$( and TX$B_2$( were nearkedly reduced and the production of prostacyclin was increased. The formation of TXBE was reduced by ginsenoside $Rb_2$, Rc, and Re, however the production of 6-Keto-PGF1 was increased dose dependently up to 1 mg/ml. Moreover, platelet aggregations induced by arachidonic acid and U46619 (9.11-methanepoxy PG$H_2$), TX$A_2$ mimetics, were also inhibited by three ginsenosides. The effect of G-Re on prostacyclin synthetase was inhibited by tranylcypromine, prostacyclin synthetase inhibitor. These results suggest that Ginseng saponins may not directly act on cyclooxygenase but affect on the divergent pathway from endoperoxide.

• Journal of Periodontal and Implant Science
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• v.23 no.2
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• pp.243-259
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• 1993

The bone resorbing activity of $PGE_2$ and elevated level of prostaglandins(PGs) and thromboxanes (TXs) in inflamed gingiva which are cyclooxygenase(C) metabolites have been well documented. Nonsteroidal anti-inflammatory drugs(NSAIDs) have been known to suppress gingival inflammation and bone resorption through the specific inhibitory action on the C pathway thereby decrease of various C metabolites. Recent studies provide unequivocal results that gingival tissue metabolizes arachidonic acid(AA) mainly through lipoxygenase(L) pathway. And the results of our previous experiments suggest that indomethacin may have inhibitory action on L as well as C. Thus we started this study to show the influences of several C inhibitors on the L activity at therapeutic and toxic dosage. Periodontal tissue samples were obtained from patients with advanced periodontitis and incubated with $^{14}C-AA(0.2{\mu}Ci)$ and various enzyme inhibitors. The tissue lipid extracts were separated by means of thin layer chromatography(TLC) and analyzed by means of autoradiography and TLC analyzer. Our results showed that aspirin inhibited C more selectively than L, however at higher concentration it also decreased HETEs production significantly. Indomethacin showed dose-dependent inhibition of L as well as C and all of the L metabolites were decreased to the same degree by high concentration of indomethacin. AA-861, which is an experimental tool of selective L inhibitor, showed inhibition of HETEs production but no effect on the production of $TXB_2$, PGs and $LTB_4$. Various propionic acid derivatives NSAIDs(ibuprofen, flurbiprofen, naproxen) showed the same patterns of effect on AA metabolism each other that was profound inhibition of PGs production, to the less degree HETEs and $TXB_2$ production, and of no effect on the $LTB_4$ production.