• International Journal of Oral Biology
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• 제39권1호
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• pp.15-22
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• 2014

Aggregatibacter actinomycetemcomitans is an important pathogen in the development of localized aggressive periodontitis. Lipopolysaccharide (LPS) is a virulent factor of periodontal pathogens that contributes to alveolar bone loss and connective tissue degradation in periodontal disease. Our present study was designed to investigate the cytokine expression and signaling pathways regulated by A. actinomycetemcomitans LPS (Aa LPS). Cytokine gene expression profiling in RAW 264.7 cells was performed by microarray analyses. The cytokine mRNA and protein levels and related signaling pathways induced by Aa LPS were measured by RT-PCR, ELISA and western blotting. Microarray results showed that Aa LPS strongly induced the expression of NF-${\kappa}B$, NF-${\kappa}B$-related genes, inflammatory cytokines, TNF-${\alpha}$ and IL-$1{\beta}$ in RAW 264.7 cells. NF-${\kappa}B$ inhibitor pretreatment significantly reduced the levels of TNF-${\alpha}$ and IL-$1{\beta}$ mRNA and protein. In addition, the Aa LPS-induced TNF-${\alpha}$ and IL-$1{\beta}$ expression was inhibited by p38/JNK MAP kinase inhibitor pretreatment. These results show that Aa LPS stimulates TNF-${\alpha}$ and IL-$1{\beta}$ expression through NF-${\kappa}B$ and p38/JNK activation in RAW 264.7 cells, suggesting the essential role of this pathway in the pathogenesis of localized aggressive periodontitis.

• BMB Reports
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• 제50권12호
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• pp.640-646
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• 2017

Regulatory B cells, also well-known as IL-10-producing B cells, play a role in the suppression of inflammatory responses. However, the epigenetic modulation of regulatory B cells is largely unknown. Recent studies showed that the bromodomain and extra-terminal domain (BET) protein inhibitor JQ1 controls the expression of various genes involving cell proliferation and cell cycle. However, the role of BET proteins on development of regulatory B cells is not reported. In this study, JQ1 potently suppressed IL-10 expression and secretion in murine splenic and peritoneal B cells. While bromodomain-containing protein 4 (BRD4) was associated with $NF-{\kappa}B$ on IL-10 promoter region by LPS stimulation, JQ1 interfered the interaction of BRD4 with $NF-{\kappa}B$ on IL-10 promoter. In summary, BRD4 is essential for toll like receptor 4 (TLR4)-mediated IL-10 expression, suggesting JQ1 could be a potential candidate in regulating IL-10-producing regulatory B cells in cancer.

• Archives of Pharmacal Research
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• 제27권9호
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• pp.954-960
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• 2004

Expression of the NF-$textsc{k}$B-dependent genes responsible for inflammation, such as TNF-$\alpha$, IL-1$\beta$, and nitric oxide synthase (NOS), contributes to chronic inflammation which is a major cause of neurodegenerative diseases (i.e. Alzheimer＇s disease). Although NF-$textsc{k}$B plays a biphasic role in different cells like neurons and microglia, controlling the activation of NF-$textsc{k}$B is important for its negative feedback in either activation or inactivation. In this study, we found that ursodeoxycholic acid (UDCA) inhibited I$textsc{k}$B$\alpha$ degradation to block expression of the NF-$textsc{k}$B-dependent genes in microglia when activated by $\beta$-amyloid peptide (A$\beta$). We also showed that when microglia is activated by $A\beta$42, the expression of A20 is suppressed. These findings place A20 in the category of ' protective ' genes, protecting cells from pro-inflammatory reper-toires induced in response to inflammatory stimuli in activated microglia via NF-$textsc{k}$B activation. In light of the gene and proteins for NF-$textsc{k}$B-dependent gene and inactivator for NF-$textsc{k}$B (I$textsc{k}$B$\alpha$), the observations now reported suggest that UDCA plays a role in supporting the attenuation of the production of pro-inflammatory cytokines and NO via inactivation of NF-$textsc{k}$B. Moreover, an NF-$textsc{k}$B inhibitor such as A20 can collaborate and at least enhance the anti-inflammatory effect in microglia, thus giving a potent benefit for the treatment of neurodegenerative diseases such as AD.uch as AD.

• The Korean Journal of Physiology and Pharmacology
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• 제4권5호
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• pp.339-346
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• 2000

Using murine immortalized microglial cells (BV-2), we examined the regulation of RANTES production stimulated by lipopolysaccharide (LPS), focusing on the role of mitogen-activated protein kinase (MAPK) and nuclear factor $(NF)-{\kappa}B.$ The result showed that RANTES (regulated upon activation of normal T cell expressed and secreted) was induced at the mRNA and protein levels in a dose- and time-dependent manner in response to LPS. From investigations of second messenger pathways involved in regulating the secretion of RANTES, we found that LPS induced phosphorylation of extracellular signal-regulated kinase (Erk), p38 MAPK and c-Jun-N-terminal kinase (JNK), and activated $(NF)-{\kappa}B.$ To determine whether this MAPK phosphorylation is involved in LPS-stimulated RANTES production, we used specific inhibitors for p38 MAPK and Erk, SB 203580 and PD 98059, respectively. LPS-induced RANTES production was reduced approximately 80% at $25\;{\mu}M$ of SB 203580 treatment. But PD 98059 did not affect RANTES production. Pyrrolidine-dithiocarbamate (PDTC), $(NF)-{\kappa}B$ inhibitor, reduced RANTES secretion. These results suggest that LPS-induced RANTES production in microglial cells (BV-2) is mainly mediated by the coordination of p38 MAPK and $(NF)-{\kappa}B$ cascade.

• Journal of Nutrition and Health
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• 제51권4호
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• pp.323-329
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• 2018

만성 염증은 현대사회에서 다양한 질병을 유발하는 주요 원인으로 작용하기 때문에 항염증 활성을 가진 소재의 연구는 염증 관련 질병의 예방과 치료에 있어서 중요하다. 본 연구에서는 LPS에 의해 염증을 유도한 RAW 264.7 세포에서 제주왕지네 (Scolopendra subspinipes mutilans) 에탄올 추출물의 염증 조절 기전을 확인하여 항염증 소재로서의 가능성을 조사하였다. LPS에 의해 증가된 NO 생성과 iNOS 발현은 왕지네 추출물에 의해 감소되었고 pro-inflammatory cytokine으로 알려진 $IL-1{\beta}$, IL-6의 발현에서도 유사한 결과를 보였다. 왕지네 추출물은 LPS에 의해 유도된 $NF-{\kappa}B$의 핵으로의 전이와 $I{\kappa}B$의 분해를 동시에 억제하였고 $NF-{\kappa}B$ inhibitor의 처리는 NO 생성과 iNOS 발현을 더욱 억제하였다. 이상의 결과는 왕지네 추출물이 $NF-{\kappa}B$ 활성 조절을 통해 염증 반응의 지표로 사용되는 NO 생성 및 pro-inflammatory cytokine의 발현을 효과적으로 억제하여 항염 활성을 가진 소재로서의 가능성을 보여주는 것으로 염증에 의해 유발되는 다양한 질병을 효율적으로 제어하는 소재를 개발하는데 있어서 주요한 정보를 제공할 것으로 생각된다.

• Journal of Microbiology and Biotechnology
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• 제17권8호
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• pp.1338-1343
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• 2007

Angiogenesis is an essential step in tumor progress and metastasis. Accordingly, small molecules that inhibit angiogenesis would appear to be a promising way to cure angiogenesis-related diseases, including cancer. In the present study, we report that streptochlorin, a small molecule from marine actinomycete, exhibits a potent antiangiogenic activity. The compound potently inhibited endothelial cell invasion and tube formation stimulated with vascular endothelial cell growth factor (VEGF) at low micromolar concentrations where it showed no cytotoxicity to the cells. In addition, streptochlorin inhibited TNF-${\alpha}$-induced $NF-{\kappa}B$ activation in the newly developed cell-based reporter gene assay. These data demonstrate that streptochlorin is a new inhibitor of $NF-{\kappa}B$ activation and can be a basis for the development of novel anti-angiogenic agents.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.146.2-147
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• 2003

The benzoxathiol LYR-71 compound was discovered as an inhibitor of NF-kB transcriptional activity with an IC50 value of 5.4 uM. Furthermore, benzoxathiol LYR-71 compound inhibited the NF-kB binding activity to DNA in a dose-dependent manner, which was identified by EMSA with oligonucleotide corresponding to NF-kB consensus sequence. It is well known that NF-kB is an important transcription factor to regulate the expression of inflammatory enzymes (iNOS and COX-2) and cytokines (TNF, IL-1 and IL-6). (omitted)

• The Korean Journal of Physiology and Pharmacology
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• 제25권4호
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• pp.307-319
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• 2021

Dysregulation of the Wnt pathway causes various diseases including cancer, Parkinson's disease, Alzheimer's disease, schizophrenia, osteoporosis, obesity and chronic kidney diseases. The modulation of dysregulated Wnt pathway is absolutely necessary. In the present study, we evaluated the anti-inflammatory effect and the mechanism of action of Wnt-C59, a Wnt signaling inhibitor, in lipopolysaccharide (LPS)-stimulated epithelial cells and macrophage cells. Wnt-C59 showed a dose-dependent anti-inflammatory effect by suppressing the expression of proinflammatory cytokines including IL6, CCL2, IL1A, IL1B, and TNF in LPS-stimulated cells. The dysregulation of the Wnt/β-catenin pathway in LPS stimulated cells was suppressed by WntC59 treatment. The level of β-catenin, the executor protein of Wnt/β-catenin pathway, was elevated by LPS and suppressed by Wnt-C59. Overexpression of β-catenin rescued the suppressive effect of Wnt-C59 on proinflammatory cytokine expression and nuclear factor-kappa B (NF-κB) activity. We found that the interaction between β-catenin and NF-κB, measured by co-immunoprecipitation assay, was elevated by LPS and suppressed by Wnt-C59 treatment. Both NF-κB activity for its target DNA binding and the reporter activity of NF-κB-responsive promoter showed identical patterns with the interaction between β-catenin and NF-κB. Altogether, our findings suggest that the anti-inflammatory effect of Wnt-C59 is mediated by the reduction of the cellular level of β-catenin and the interaction between β-catenin and NF-κB, which results in the suppressions of the NF-κB activity and proinflammatory cytokine expression.

• BMB Reports
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• 제42권6호
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• pp.380-386
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• 2009

In neurodegenerative diseases, such as Alzheimer' and Parkinson', microglial cell activation is thought to contribute to CNS injury by producing neurotoxic compounds. Prothrombin and kringle-2 increase levels of NO and the mRNA expression of iNOS, IL-1$\beta$, and TNF-$\alpha$ in microglial cells. In contrast, the human prothrombin kringle-2 derived peptide NSA9 inhibits NO release and the production of pro-inflammatory cytokines such as IL-1$\beta$, TNF-$\alpha$, and IL-6 in LPS-activated EOC2 microglia. In this study, we investigated the anti-inflammatory effects of NSA9 in human prothrombin- and kringle-2-stimulated EOC2 microglia. Treatment with 20-100 ${\mu}M$ of NSA9 attenuated both prothrombin- and kringle-2-induced microglial activation. NO production induced by MAPKs and NF-$\kappa$B was similarly reduced by inhibitors of ERK (PD98059), p38 (SB203580), NF-$\kappa$B (N-acetylcysteine), and NSA9. These results suggest that NSA9 acts independently as an inhibitor of microglial activation and that its effects in EOC2 microglia are not influenced by the presence of kringle-2.

• Asian Pacific Journal of Cancer Prevention
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• 제13권5호
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• pp.2379-2383
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• 2012

Objective: To investigate possible signal pathway involvement in multi-drug resistant P-glycoprotein (P-gp) expression induced by cyclooxygenase-2 (COX-2) in a human gastric adenocarcinoma cell line stimulated with pacliaxel (TAX). Methods: The effects of TAX on SGC7901 cell growth with different doses was assessed by MTT assay, along with the effects of the COX-2 selective inhibitor NS-398 and the nuclear factor-KB (NF-KB) pathway inhibitor pyrrolidine dithiocarbamate (PDTC). Influence on COX-2, NF-KB p65 and P-gp expression was determined by Western blotting. Results: TAX, NS-398 and PDTC all reduced SGC7901 growth, with dosedependence. With increasing dose of TAX, the expression of COX-2, p65 and P-gp showed rising trends, this being reversed by NS-398. PDTC also caused decrease in expression of p65 and P-gp over time. Conclusion: COX-2 may induce the expression of P-gp in SGC7901 cell line via the NF-kappa B pathway with pacliaxel stimulation.