• Journal of Microbiology and Biotechnology
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• v.15 no.1
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• pp.183-187
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• 2005

Abstract The cancer chemopreventive potential of chitosanoligosaccharides was investigated by measuring the induction of quinone reductase and glutathione S-transferase activities and inhibition of cytochrome P450 1A1, 2B1, and 2E1 activities. Chitosanoligosaccharide I (1-${\kappa}$Da${\kappa}$Da) significantly induced glutathione S-transferase activity with a maximal 1.5-fold increase at 500 ${\mu}$g/ml, while chitosanoligosaccharide II (3-${\kappa}$Da${\kappa}$Da) (500 ${\mu}$g/ml) strongly induced quinone reductase (p<0.01) and glutathione S-transferase (p<0.005) activities. The in vitro incubation of rat liver microsomes with chitosanoligosaccharides I and II (2.5, 5, 50, and 500 ${\mu}$g/ml) showed a dose-dependent inhibiton of cytochrome P450 1A1, 2B1, and 2E1 activities. Chitosanoligosaccharide II was a more potent inhibitor of cytochrome P450 2B1 activity than chitosanoligosaccharide I. Accordingly, these findings suggest that chitosanoligosaccharides are potential chemopreventive agents.

• BMB Reports
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• v.39 no.6
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• pp.788-793
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• 2006

Bacterial DNA containing immunostimulatory CpG motifs can stimulate antigen-presenting cells to express co-stimulatory molecules and to produce various cytokines in vivo and in vitro. In this study, we fragmented macromolecular E.coli genomic DNA with DNase I, and analyzed the ability of the resulting DNA fragments to induce the NF-${\kappa}B$ activation and humoral immune response. Furthermore, using computational analysis and luciferase assay for synthetic ODNs based on the sequence of the immunostimulatory DNA fragments (DF-ODNs), an active component of DF-ODNs sequences was investigated. Experimental results demonstrated that DF-ODN is optimal for the NF-${\kappa}B$-responsive promoter activation in the mouse macrophage cell line and the humoral immune response in vivo. In agreement with the activity of the DF-ODNs processed by DNase I, a synthetic ODN based on the DF-ODN sequences is potent at inducing IL-12 mRNA expression in primary dendritic cells. These results suggest that the discovery and characterization of a highly active natural CpG-ODN may be achieved by the analyses of bacterial DNA fragments generated by a nuclease activity.

• Journal of Physiology & Pathology in Korean Medicine
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• v.22 no.3
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• pp.678-683
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• 2008

Aconitum pseudo-laeve var. erectum has traditionally been used for the treatment of water retention in the body. Administration of the aqueous extract of Aconitum pseudo-laeve var. erectum has the efficiency of anti-inflammatory activity and modulates the intestinal immune system. However, the mechanism of anti-inflammatory action of Aconitum pseudo-laeve var. erectum has not been clarified yet. In the present study, the effect of Aconitum pseudo-laeve var. erectum against LPS-stimulated expressions of COX-2 and iNOS in cells of the murine RAW 264.7 macrophages was investigated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, reverse transcription- polymerase chain reaction (RT-PCR), PGE2 immunoassay, and NO detection. The results of the present study indicate that Aconitum pseudo-laeve var. erectum is a potent inhibitor of the LPS-induced NO and $PGE_{2}$ production by blocking iNOS and $NF{\kappa}B$ activation in RAW 264.7 macrophages. These findings suggest that Aconitum pseudo-laeve var. erectum is a potential therapeutic for the treatment of inflammatory syndrome.

• Journal of Periodontal and Implant Science
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• v.35 no.3
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• pp.799-811
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• 2005

This study was carried out to examine the potency of the three surface compo- nents from Porphyromonas gingivalis to stimulate the murine macrophage cell line RAW264.7 to synthesize the pro-inflammatory cytokine tumor necrosis factor alpha($TNF-{\alpha}$) and nitric oxide (NO). Lipopolysaccharide(LPS). lipid A-associated proteins(LAP) and saline-extractable surface -associated material(SAM) were isolated from P. gingivalis 381. $TNF-{\alpha}$ release into culture supernatants was determined by two-site ELISA. NO production was assayed by measuring the accumulation of nitrite in culture supernatants. Western blot analysis of iNOS and analysis of reverse transcription(RT)-PCR products were carried out. The surface components extracted from this bacterium were almost equally potent in stimulating release of $TNF-{\alpha}$ and NO by RAW264.7 cells. $TNF-{\alpha}$ that was being measured immunologically was due to activation of $TNF-{\alpha}$ gene transcription. The present study clearly shows that P. gingivalis surface components fully induced iNOS expression in RAW264.7 cells in the absence of other stimuli. The ability of P. gingivalis surface components to promote the production of $TNF-{\alpha}$ and NO may be important in the pathogenesis of inflammatory periodontal disease.

• Natural Product Sciences
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• v.22 no.1
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• pp.53-59
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• 2016

Anti-inflammatory effects of dihydrobenzofuran neolignans isolated from Euonymus alatus leaves and twigs were evaluated in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophage cells. Six neolignans, (+)-simulanol (1), (+)-dehydrodiconiferyl alcohol (2), (-)-simulanol (3), (-)-dehydrodiconiferyl alcohol (4), (+)-dihydrodehyrodiconiferyl alcohol (5), threo-buddlenol B (6) effectively inhibited the production of nitric oxide (NO) induced by LPS, and the activity of iNOS. (-)-dehydrodiconiferyl alcohol (4), which showed the most potent inhibitory activity, attenuated the activity of iNOS enzyme and also the expression of iNOS and COX-2 proteins. The subsequent production of pro-inflammatory cytokines, interleukin-$1{\beta}$, interleukin-6, tumor necrosis factor-${\alpha}$ and prostaglandin E2 were also inhibited by the pretreatment of RAW264.7 cells with (-)-dehydrodiconiferyl alcohol (4). These neolignans are thought to contribute to anti-inflammatory effects of E. alatus, and expected to be potential candidates to prevent/treat inflammation-related diseases.

• Biomolecules & Therapeutics
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• v.29 no.5
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• pp.562-570
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• 2021

Topoisomerase IIα has been a representative anti-cancer target for decades thanks to its functional necessity in highly proliferative cancer cells. As type of topoisomerase IIα targeting drugs, topoisomerase II poisons are frequently in clinical usage. However, topoisomerase II poisons result in crucial consequences resulted from mechanistically induced DNA toxicity. For this reason, it is needed to develop catalytic inhibitors of topoisomerase IIα through the alternative mechanism of enzymatic regulation. As a catalytic inhibitor of topoisomerase IIα, AK-I-191 was previously reported for its enzyme inhibitory activity. In this study, we clarified the mechanism of AK-I-191 and conducted various types of spectroscopic and biological evaluations for deeper understanding of its mechanism of action. Conclusively, AK-I-191 represented potent topoisomerase IIα inhibitory activity through binding to minor groove of DNA double helix and showed synergistic effects with tamoxifen in antiproliferative activity.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.27-27
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• 2022

(-)-Epicatechin (EC), a primary form of flavan-3ol and a building block of proanthocyanidins, has health benefits as it is a potent antioxidant. So far, no quantitative trait loci (QTLs) associated with EC have yet been identified in soybean. In this study, QTLs for EC and hilum color were identified in recombinant inbred lines (RILs) derived from the varieties Jinpung and IT109098 using high-resolution single nucleotide polymorphism linkage mapping. This revealed two major QTLs for EC content, qEC06 and qEC08. qEC06 spanned the T Locus encoding flavonoid 3'-hydroxylase. qEC08, located near the I locus on Chr08, was also a major QTL for hilum color; however, allelic stacking of qEC08 and I revealed no relationship between I and EC content. RILs with IT 109098 alleles at both qEC06 and qEC08 had higher EC content than other lines. These results will enable the production of soybean varieties with high EC content via marker-assisted selection.

• Biomolecules & Therapeutics
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• v.23 no.2
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• pp.119-127
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• 2015

Chalcones (1,3-diaryl-2-propen-1-ones), a subfamily of flavonoid, are widely known to possess potent anti-inflammatory and anti-oxidant properties. In this study, we investigated the effect of 3-(4-Hydroxyphenyl)-1-(thio3-(4-Hydroxyphenyl phen-2-yl)prop-2-en-1-one (TI-I-175), a synthetic chalcone derivative, on endotoxin-induced expression of monocyte chemoattractant protein-1 (MCP-1), one of the key chemokines that regulates migration and infiltration of immune cells, and its potential mechanisms. TI-I-175 potently inhibited MCP-1 mRNA expression stimulated by lipopolysaccharide (LPS) in RAW 264.7 macrophages without significant effect on cell viability. Treatment of cells with TI-I-175 markedly prevented LPS-induced transcriptional activation of activator protein-1 (AP-1) as measured by luciferase reporter assay, while nuclear factor-${\kappa}B$ (NF-${\kappa}B$) activity was not inhibited by TI-I-175, implying that TI-I-175 suppressed MCP-1 expression probably via regulation of AP-1. In addition, TI-I-175 treatment significantly inhibited LPS-induced Akt phosphorylation and led to a significant decrease in reactive oxygen species (ROS) production by LPS, which act as up-stream signaling events required for AP-1 activation in RAW 264.7 macrophages. Taken together, these results indicate that TI-I-175 suppresses MCP-1 gene expression in LPS-stimulated RAW 264.7 macrophages via suppression of ROS production and Akt activation.

• Proceedings of the Korean Society of Applied Pharmacology
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• 2003.11a
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• pp.101-101
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• 2003

Prostaglandins (PGs) and nitric oxide (NO) produced by inducible cyclooygenase (COX-2) and nitric oxide synthase (iNOS), respectively, have been implicated as important mediators in the process of inflammation and carcinogenesis. On this line, the potential COX-2 or iNOS inhibitors have been considered as anti-inflammatory and cancer chemopreventive agents. In our continuing efforts of searching for novel cancer chemopreventive agents from natural products, we isolated natural sesquiterpenoids as potential COX-2 and iNOS inhibitors in cultured lipopolysaccharide (LPS)-activated mouse macrophage RAW 264.7 cells. Alantolactone, a natural eudesmane-type sesquiterpenoid, exhibited a potent inhibition of COX-2 (IC50 = 0.4 $\mu\textrm{g}$/$m\ell$) and iNOS activity (IC50 = 0.08 $\mu\textrm{g}$/$m\ell$) in the assay system determined by PGE2 and NO accumulation, respectively. The inhibitory potential of alantolactone on the PGE2 and NO production was well coincided with the suppression of COX-2 and iNOS protein and mRNA expression in LPS-induced macrophages. Furthermore, alantolactone inhibited NF-kB but not AP-l binding activity on nuclear extracts evoked by LPS-stimulated macrophage cells, suggesting the possible involvement of NF-kB in the regulation of COX-2 and iNOS expression. In further study with COX-2-expressing human colon HT-29 cells, alantolactone inhibited the cell proliferation, down-regulated COX-2, and inhibited the ERK phosphorylation in the early time. These results suggest that a natural sesquiterpenoid alantolactone might be a potential lead candidate for further developing COX-2 or iNOS inhibitor possessing cancer chemopreventive or anti-inflammatory activity

• IMMUNE NETWORK
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• v.9 no.5
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• pp.192-202
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• 2009

Background: Little information is available the role of Nitric Oxide (NO) in host defenses during human tuberculosis (TB) infection. We investigated the modulating factor(s) affecting NO synthase (iNOS) induction in human macrophages. Methods: Both iNOS mRNA and protein that regulate the growth of mycobacteria were determined using reverase transcriptase-polymerase chain reaction and western blot analysis. The upstream signaling pathways were further investigated using iNOS specific inhibitors. Results: Here we show that combined treatment with 1,25-dihydroxyvitamin D3 (1,25-D3) and Interferon (IFN)-${\gamma}$ synergistically enhanced NO synthesis and iNOS expression induced by Mycobacterium tuberculosis (MTB) or by its purified protein derivatives in human monocyte-derived macrophages. Both the nuclear factor-${\kappa}B$ and MEK1-ERK1/2 pathways were indispensable in the induction of iNOS expression, as shown in toll like receptor 2 stimulation. Further, the combined treatment with 1,25-D3 and IFN-${\gamma}$ was more potent than either agent alone in the inhibition of intracellular MTB growth. Notably, this enhanced effect was not explained by increased expression of cathelicidin, a known antimycobacterial effector of 1,25-D3. Conclusion: These data support a key role of NO in host defenses against TB and identify novel modulating factors for iNOS induction in human macrophages.