• Proceedings of the PSK Conference
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• 2002.10a
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• pp.313.1-313.1
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• 2002

Nitric oxide (NO) production through the inducible nitric-oxide synthase (iNOS) pathway has been implicated in inflammatory diseases and cellular injury. Inhibition of various genes related to inflammation, including iNOS is one of the major roles of well-known anti-inflammatory drugs. In the present study, the effects of ceramide analogs on iNOS expression and NO production were evaluated to investigate how ceramide and its structurally related analogs modulate NO-mecliated cellular signals and inflammation. (omitted)

• Journal of Life Science
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• v.16 no.2 s.75
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• pp.192-198
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• 2006

Epidemiological studies have demonstrated an association between exposure to diesel exhaust particles (DEP) and adverse cardiopulmonary effects. Despite the epidemiological proof, the pathogenesis of DEP-related pulmonary diseases remain poorly understood. So, comprehensive in vivo and in vitro researches are required to know the effects of DEP on diverse lung diseases. Alveolar macrophages (AM) and airway epithelial cells are known as important cellular targets in DEP-induced lung diseases. Other studies have shown that nitric oxide (NO) is involved in particle matter induced lung injury. The present study was undertaken to determine whether DEP has an synergistic effects on lipopolysaccharide (LPS)-induced NO formation and inducible nitric oxide synthase (iNOS) with nitrotyrosilated-protein formation in cultured primary alveolar macrophages. The formation of NO was determined through the Griess reaction in the cultured medium and iNOS with nitrotyrosilated-proteins are analyzed by immunohistochemical staining and Western analysis. The results indicate that DEP exposure does not induce NO formation by itself, however DEP showed significant synergistic effects on LPS-induced NO formation. So, our results suggest that DEP inhalation could aggravate inflammatory lung disease through NO formation.

• Journal of Applied Biological Chemistry
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• v.64 no.4
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• pp.375-382
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• 2021

Biorenovation is a microbial enzyme-based structural modification of component compounds in natural products and synthetic compounds including plant extracts with the potential benefits of improved biological activities compared with its reaction substrates. In this study, we investigated the anti-inflammatory activity of Distylium racemosum leaf extract and D. racemosum leaf biorenovation extract (DLB). As a result, DLB inhibited nitric oxide, prostaglandin E2, and inflammatory cytokines including tumor necrosis factor-α, interleukin-6, interleukin-1β at non-toxic concentrations. In addition, DLB significantly inhibited inducible nitric oxide synthase and cyclooxygenase-2 on LPS-treated RAW 264.7 macrophages. Based on these results, we suggest that the DLB could be used as a potent anti-inflammatory agents. It also suggests that the application of biological evolution has potential usefulness to increase the practical value of natural products.

• 대한치주과학회:학술대회논문집
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• 2005.11a
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• pp.153-153
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• 2005

• 대한치주과학회:학술대회논문집
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• 2005.11a
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• pp.91-91
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• 2005

• 대한치주과학회:학술대회논문집
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• 2004.11a
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• pp.47-47
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• 2004

• 대한치주과학회:학술대회논문집
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• 2004.11a
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• pp.135-135
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• 2004

• 대한치주과학회:학술대회논문집
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• 2004.11a
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• pp.136-136
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• 2004

• 대한치주과학회:학술대회논문집
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• 2003.11a
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• pp.89-90
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• 2003

• Proceedings of the Korean Society of Applied Pharmacology
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• 1998.11a
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• pp.176-176
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• 1998

An enhanced formation of nitric oxide (NO) is an important mediator of hypotention, peripheral vasodilation and vascular hyporeactivity to vasoconstrictor agents in endotoxaemia. And tumor necrosis factor (TNF${\alpha}$), as a primary mediator of circulatory shock has been known to induce inducible nitric oxide synthase (i-NOS), leading to excessive production of NO. We isolated two sesquiterpene lactone compounds from Saussurea lappa and their structures were elucidated as dehydrocostus lactone and costunolide. These compounds inhibit the production of both NO and TNF${\alpha}$ by LPS (1 $\mu\textrm{g}$/$m\ell$)-activated Raw 264.7 cells. NO was measured spectropho-tometrically as nitrite by the Griess reagent and TNF${\alpha}$ by ELISA. Dehydrocostus lactone (IC$\sub$50/ : 3.0 ${\mu}$M) and costunolide (IC$\sub$50/ : 4.5 ${\mu}$M) inhibited the production of NO in LPS-activated Raw 264.7 cells by suppressing inducible nitric oxide synthase enzyme expression. These compounds also decreased the TNF${\alpha}$ levels in LPS-activated system in vitro and in vivo.