• 한국자원식물학회지
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• 제27권3호
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• pp.209-214
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• 2014

In this study, we investigated whether A. distichum decreases the production of inflammatory mediators through downregulation of the NF-${\kappa}B$ and ERK pathway. Our data indicated that A. distichum leaf inhibits the overexpression of iNOS in protein and mRNA levels, and subsequently blocked LPS-mediated NO overproduction in RAW264.7 cells. A. distichum leaf inhibited $I{\kappa}B-{\alpha}$ degradation and p65 nuclear translocation, and subsequently suppressed transcriptional activity of NF-${\kappa}B$ in LPS-stimulated RAW264.7 cells. In addition, A. distichum leaf suppressed LPS-induced ERK1/2 activation by decreasing phosphorylation of ERK1/2. These findings suggest that A. distichum leaf shows anti-inflammatory activities through suppressing ERK-mediated NF-${\kappa}B$ activation in mouse macrophage.

• Tuberculosis and Respiratory Diseases
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• 제48권5호
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• pp.682-698
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• 2000

Glucocorticoid receptor (GR) functions as a suppressor of inflammation by inhibiting the expression of many cytokine genes activated by NF-${\kappa}B$. The goal of this study is to investigate the mechanism by which GR repress NF-${\kappa}B$ activation in lung epithelial cells. We used A549 and BEAS-2B lung epithelia! cell lines. Using Ig$G{\kappa}$-NF-${\kappa}B$ luciferase reporter gene construct, we found that dexamethasone significantly suppressed TNF-$\alpha$-induced NF-${\kappa}B$ activation and the overexpression of GR showed dose-dependent reduction of TNF-$\alpha$-induced NF-${\kappa}B$ activity in both cell lines. However, DNA binding of NF-${\kappa}B$ induced by TNF-$\alpha$ in electromobility shift assay was not inhibited by dexamethasone. Super shift assay with anti-p65 antibody demonstrated the existence of p65 in NF-${\kappa}B$ complex induced by $\alpha$ Western blot showed that $I{\kappa}B{\alpha}$ degradation induced by TNF-$\alpha$ was not affected by dexamethasone and $I{\kappa}B{\kappa}$ was not induced by dexamethasone, neither. To evaluate p65 specific transactivation, we adopted co-transfection study of Gal4-p65TA1 or TA2 fusion protein expression system together with 5xGal4-luciferase vector. Co-transfection of GR with Gal4-p65TA1 or TA2 repressed luciferase activity profoundly to the level of 10-20% of p65TA1- or TA2-induced transcriptional activity. And this transrepressional effect was abolished by co-transfection of CBP of SRC-1 expression vectors. These results suggest that GR-mediated transrepression of NF-${\kappa}B$ in lung epithelial cells is through competing for binding to limiting amounts of transcriptional coactivators, CBP or SRC-1.

• BMB Reports
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• 제42권3호
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• pp.148-153
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• 2009

Pyrrolidine dithiocarbamate (PDTC) is a stable anti-oxidant or pro-oxidant, depending on the situation, and it is widely used to inhibit the activation of NF-${\kappa}B$. We recently reported that PDTC activates the MIP-2 gene in a NF-${\kappa}B$-independent and c-Jun-dependent manner in macrophage cells. In this work, we found that PDTC activates signal transduction pathways in mouse ES cells. Among the three different mitogen-activated protein kinase (MAPK) pathways, including the extracellular-signal-regulated kinase (ERK), p38 MAP kinase, and stress-activated protein kinase (SAPK)/Jun N-terminal kinase (JNK) pathways, only the ERK pathway was significantly activated in mouse ES cells after stimulation with PDTC. Additionally, we observed a synergistic activation of ERK and induction of c-Fos after stimulation with PDTC in the presence of mouse embryonic fibroblast (MEF) conditioned medium. In contrast, another NF-${\kappa}B$ inhibitor, BMS-345541, did not activate the MAP kinase pathways or induce expression of c-Fos. These results suggest that changes in the presence of the NF-${\kappa}B$ inhibitor PDTC should be carefully considered when it used with mouse ES cells.

• 대한한방내과학회지
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• 제20권1호
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• pp.99-110
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• 1999

Effects of Chiyangtang(CYT) on H. pylori-induced increase of interleukin 8 and interleukin 1 gene expression was studied in Kato Ⅲ cell line, a human stomach epithelial cell line. Treatment of H. pylori to the cell culture signifant!y increased IL-8 and IL-1 mRNA synthesis. When CYT was added along with H. pylori, the increase of IL-8 and IL-1 mRNA synthesis was blocked. Activation of transcription factor $NF-{\kappa}B$ and AP-1 which were known to important in IL-8 and IL-1 gene expression was also studied using chloramphenicol acetyltransferase(CAT) assay. Treatment of H. pylori increased activation of $NF-{\kappa}B$ and AP-l and CYT effectively protected the activation. Electrophoretic mobility shift assay suggested that CYT effectively inhibited DNA binding of $NF-{\kappa}B$ and AP-l to their cognate site. These results suggested that CYT could prevent stomach diseases through the down regulation of IL -8 and IL-l gene expression which might be mediated by the inhibition of $NF-{\kappa}B$ and AP-1 activities and their binding to DNA.

• Preventive Nutrition and Food Science
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• 제4권3호
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• pp.209-214
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• 1999

In this study, the effectof ethanol and acetaldehyde on DNA binding activities of NF-$textsc{k}$B and AP-1 were evaluated in C6 rat glial cells. Both NF-$textsc{k}$B and AP-1 are important transcription factors for the expression of various cytokines in glial cells. Our data showed that neither ethanol nor acetaldehyde induced conspicuous cell death of C6 cells at clinically realistic concentrations. When the DNA binding activities of nuclear NF-$textsc{k}$B and AP-1 were estimated using electrophoretic mobility shift assay (EMSA), ethanol(0.3%) or acetaldehyde(1mM) induced transient activation of these transcription factors, which attained peak levels at 4~8 hours and declined to basal levels at 12 hours after treatement . The supershift analysis showed that the increased activities of NF-$textsc{k}$B in ethanol/acetaldehyde-treated C6 cells were due to the preferential induction of p65/p50 heterodimer complex. The DNA binding activities of these transcriptional factors decreased below basal levels when cells were cultured with either ethanol or acetaldehyde for 24 hours, and showed the inhibitory effect of chronic ehtanol /acetaldehyde treatment on the activities of these transsriptional factors. Our data indicate that either ethanol or acetaldehyde can induce functional changes of glial cells throught bi-directional modulation of NF-$textsc{k}$B and AP-1 DNA binding activities.

• Tuberculosis and Respiratory Diseases
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• 제50권1호
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• pp.52-66
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• 2001

연구배경 : 폐상피세포가 능동적으로 IL-8을 분비한다는 것은 주지의 사실이다. NF-${\kappa}B$는 IL-8 발현 조절에 있어서 가장 중요한 역할을 담당하는 전사인자이다. Triptolide는 최근 밝혀진 NF-${\kappa}B$ 억제제로서 중국한약제인 뇌공등 (Tripterygium Wilfordii)에서 추출된약제이다. 연자들은 새로운 NF-${\kappa}B$ 억제제인 triptolide가 폐상피세포에서 NF-${\kappa}B$ 의존성 IL-8 유전자의triptolide가 염증성 폐질환에서 새로운 치료제로서의 가능성을 확인하기 위하여 본 연구를 시행하였다. 방법 : 폐상피세포로서 A549 사용하였고 triptolide는 미국의 Pharamagenesis(Palo Alto, CA)사로부터 제공받았다. NF-${\kappa}B$ 활성유도물질로는 IL-$1{\beta}$(R&D)와 PMA(Sigma)를 이용하였다. IL-8 유전자의 발현은 RT-PCR과 ELISA를 이용하여 측정 하였다. NF-${\kappa}B$의존성 IL-8 유전자의 전사활성을 평가하기 위하여는 IL-8 NF-${\kappa}B$ luciferase construct를 안정적으로 유전자주입한 A549 IL-8 NF-${\kappa}B$ luciferase 세포주를 제조해 사용하였고 NF-${\kappa}B$ DNA 결합은 electromobility shift assay(EMSA)를 이용하였다. p65 전사활성을 assay하기 위해서는 Gal4-p65 fusion protein expression system을 유전자주입과 luciferase assay를 통하여 시행하였다. Transcriptional coactivator의 역할을 규명 하가 위하여서는 CBP(CREB-binding protein)와 SRC-1(steroid receptor coactivator-1) 발현 벡터를 유전자 주입하고 luciferase assay를 이용하여 확인하였다. 결과 : Luciferase assay로 triptolide가 PMA와 IL-$1{\beta}$자극에 의한 IL-8 NF-${\kappa}B$ 활성을 의미있게 감소시킴을 확인하였다. IL-8 ELISA와 RT-PCR로 triptolide가 PMA와 IL-$1{\beta}$ 자극에 의해 유도되는 IL-8 발현을 각각 단백질과 mRNA 수준에서 억제함을 관찰하였다. Triptolide가 PMA와 IL-$1{\beta}$에 의한 IL-8 NF-${\kappa}B$의 전사활성을 억제시킨 반면 EMSA와 $I{\kappa}B{\alpha}$ Western blot을 이용한 실험에서는 triptolide가 NF-${\kappa}B$ DNA 결합과 $I{\kappa}B{\alpha}$의 분해에 전혀 영향을 미치지 못함을 확인하였다. 이러한 전사활성 억제와 DNA 결합 간의 불일치의 원인으로서는 DNA 결합 이후에 발생하는 핵내 에서의 transactivation에 triptolide가 영향을 미치리라고 생각되어 p65 transactivation study를 Gal4-p65T A(p65의 transactivation domain) fusion protein 발현 시스템과 luciferase assay를 이용하여 시행한 결과 triptolide가 p65 transactivation을 억제함으로써 NF-${\kappa}B$를 억제함을 확인하였다. 그러나 CBP나 SRC-1과 같은 coactivator의 역할을 규명하기 위한 유전자주입 실험에서 triptolide에 의한 p65 transactivation 억제에 대해 CBP나 SRC-1의 과발현이 별다른 영향을 미치지 못하였다. 결론 : Triptolide는 폐상피세포에서 NF-${\kappa}B$ 의존성 IL-8 유전자의 전사활성을 억제하고 그 기전은 $I{\kappa}B{\alpha}$ 경로가 아닌 핵내에서의 p65 transactivation 억제에 의해 발생하며 이에는 CBP나 SRC-1과 같은 coactivator가 관여하지 않음을 확인하였다.

• Molecules and Cells
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• 제41권8호
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• pp.762-770
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• 2018

Adiponectin, a hormone produced by adipose tissue, is very abundant in plasma, and its anti- and pro-inflammatory effects are reported. However, the mechanisms of these pro- and anti-inflammatory effects are not fully defined. Herein, we evaluated the dual inflammatory response mechanism of adiponectin in macrophages. Short-term globular adiponectin (gAd) treatment induced $I{\kappa}B{\alpha}$ degradation, $NF-{\kappa}B$ nuclear translocation, and $TNF-{\alpha}$ production in RAW 264.7 cells. Polymyxin B pretreatment did not block gAd-induced $I{\kappa}B{\alpha}$ degradation, and heated gAd was unable to degrade $I{\kappa}B{\alpha}$, suggesting that the effects of gAd were not due to endotoxin contamination. gAd activated IKK and Akt, and inhibition of either IKK or Akt by dominant-negative $IKK{\beta}$ ($DN-IKK{\beta}$) or DN-Akt overexpression blocked gAd-induced $I{\kappa}B{\alpha}$ degradation, suggesting that short-term incubation with gAd mediates inflammatory responses by activating the $I{\kappa}B/NF-{\kappa}B$ and PI3K/Akt pathways. Contrastingly, long-term stimulation with gAd induced, upon subsequent stimulation, tolerance to gAd, lipopolysaccharide, and CpG-oligodeoxynucleotide, which is associated with gAd-induced downregulation of IL-receptor-associated kinase-1 (IRAK-1) due to IRAK-1 transcriptional repression. Conclusively, our findings demonstrate that the pro- and anti-inflammatory responses to gAd in innate immune cells are time-dependent, and mediated by the activation of the $I{\kappa}B/NF-{\kappa}B$ pathway, and IRAK-1 downregulation, respectively.

• 한국식품과학회지
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• 제38권6호
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• pp.829-834
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• 2006

HIV 감염 후 AIDS로의 진행과정에서 cytokines의 변화는 필수적인 결과로서 나타나게 된다. 본 연구에서는 AIDS 동물모델을 사용하여 Pyc Cytokines발현에 미치는 영향과 조절 매개체로서 $NF-{\kappa}B$의 관련성 및 작용 기작 확인에 초점을 두었다. LP-BM5 retrovirus에 감염된 C57BL/6 생쥐를 이용하여12주간에 걸친 실험에서Pyc 투여는 Th1과 Th2 cytokines의 혈중농도를 조절하여 murine AIDS로의 진행을 억제하는 데 역할을 하는 것으로 사료된다. 특히 Th2 cytokines의 mRNA 발현을 억제함에 따라 Th1 cytokines의 혈중농도는 상대적으로 증가한 것으로 사료된다. 이러한 결과는 Pyc가 Th2 cytokines을 선택적으로 transcription level에서 조절하고 있음을 의미하고 있다. 또한 Th2 cytokines mRNA 발현 조절은 $NF-{\kappa}B$의 활성화에 의한 것으로 추정된다. 본 연구는 AIDS 동물모델에서 $NF-{\kappa}B$의 조절을 통한 cytokines의 발현 조절의 가능성을 제시함과 동시에 Pyc의 역할에 대해 자료를 제시하고 있다. 또한 향후 murine AIDS 진행 억제제로서의 Pyc의 기작에 대한 일면을 보인 것에 의의를 두고자 한다.

• Journal of Life Science
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• 제10권2호
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• pp.55-60
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• 2000

We examined the effects of Kamgil-Tang on the process of lipopolysaccharide (LPS)-induced unclear factor (NF)-${\kappa}$ Bp65 and inhibitory (I)-${\kappa}$ B${\alpha}$ alteration in RAW 264.7 cell and acute lung injury in rats. Immunoblot analysis showed that LPS-induced degradation of I-${\kappa}$ B${\alpha}$ in RAW 264.7 was inhibited by pretreatment of Kamgil-Tang. The total cells of bronchoalveolar lavage fluid by LPS challenge markedly decreased in the Kamgil-Tang pretreatment rats. Kamgil-Tang pretreatment caused also a decline in neutrophils infiltration into interstitium of the lung. In the alveolar macrophages and neutrophils, decreased NF-${\kappa}$ Bp65 and inducible nitric oxide synthase and increased I-${\kappa}$ B${\alpha}$ immunoreaction were detected in Kamgil-Tang pretreated rats compared with LPS alone treated ones. It may be concluded that Kamgil-Tang attenuates the development of LPS-induced inflammation by reduction of NF-${\kappa}$ Bp65 activation and neutrophil-mediated acute lung injury. Kamgil-Tang would be useful as a therapeutic agent for endotoxin-induced lung disease.

• Molecules and Cells
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• 제20권1호
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• pp.105-111
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• 2005

Mannasantin B, a dilignan structurally related to manssantin A, is an inhibitor of NF-${\kappa}B$ transactivation. In the present study, we found that it inhibited PMA-induced expression of IL-$1{\beta}$, IL-$1{\beta}$ mRNA, and IL-$1{\beta}$ promoter activity in U937 cells with $IC_{50}$ values of about 50 nM. It also inhibited NF-IL6- and NF-${\kappa}B$-induced activation of IL-$1{\beta}$, with $IC_{50}$ values of 78 nM and $1.6{\mu}M$, respectively, revealing a potent inhibitory effect on NF-IL6. Electrophoretic mobility shift assays showed that manassantin B had an inhibitory effect on DNA binding by NF-IL6, but not by NF-${\kappa}B$. Further analysis revealed that transactivation by NF-IL6 was also inhibited. Our results indicate that manassantin B suppresses expression of IL-$1{\beta}$ in promonocytic cells by inhibiting not only NF-${\kappa}B$ but also NF-IL6 activity. Furthermore, our observations suggest that manassantin B may be clinically useful as a potent inhibitor of NF-IL6 activity.