• Title/Summary/Keyword: NF-$\kappa$B activity

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Downregulation of $\textrm{NF}_{-{\kappa}}\textrm{B}$ activation in human keratinocytes by melanogenic inhibitors

  • Ahn, Kwang-Seok;Lee, Jinseon;Kim, Yeong-Shik
    • Proceedings of the SCSK Conference
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    • 2003.09a
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    • pp.780-803
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    • 2003
  • Exposure of skin cells, particularly keratinocytes to various nuclear factor-kappaB ($\textrm{NF}_{-{\kappa}}\textrm{B}$) activators [e.g. tumor necrosis factor-$\alpha$, interleukin-1, lipopolysaccharides, and ultraviolet light] leads to phosphorylation and degradation of the inhibitory protein, $\textrm{I}_{{\kappa}}\textrm{B}$. Liberated $\textrm{NF}_{-{\kappa}}\textrm{B}$ is translocated into the nucleus where it can change or alter expression of target genes, resulting in the secretion of extracellular signaling molecules including melanotrophic factors affecting melanocyte. In order to demonstrate the possible role of $\textrm{NF}_{-{\kappa}}\textrm{B}$ activation on the synthesis of melanotrophic factors from the keratinocytes, the activities of $\textrm{NF}_{-{\kappa}}\textrm{B}$ induced by melanogenic inhibitors (MIs) were determined in human HaCaT keratinocytes transfected with $\textrm{pNF}_{-{\kappa}}\textrm{B}$-SEAP-NPT plasmid. Transfectant cells released the secretory alkaline phosphatase (SEAP) as a transcription reporter in response to the $\textrm{NF}_{-{\kappa}}\textrm{B}$ activity and contain the neomycin phosphotransferase (NPT) gene for the dominant selection marker for geneticin resistance. MIs such as niacinamide, kojic acid, hydroquinone, resorcinol, arbutin, and glycolic acid were preincubated with transfectant HaCaT cells for 3 h and then ultraviolet B (UVB) was irradiated. $\textrm{NF}_{-{\kappa}}\textrm{B}$ activation was measured with the SEAP reporter gene assay using a fluorescence detection method. Of the Mis tested, kojic acid ($IC_{50}$/ = 60 $\mu$M) was found to be the most potent inhibitor of UVB-upregulating $\textrm{NF}_{-{\kappa}}\textrm{B}$ activation in transfectant HaCaT cells, which is followed by niacinamide ($IC_{50}$/= 540 $\mu$M). Pretreatment of the transfectant HaCaT cells with the Mis, especially kojic acid and niacinamide, effectively lowered $\textrm{NF}_{-{\kappa}}\textrm{B}$ binding measured by electrophoretic mobility shift assay. Furthermore, these two inhibitors remarkably reduced the secretion level of IL-6, one of melanotrophic factors, triggered by UV-radiation of the HaCaT cells. These observations suggest that Mis working at the in vivo level might act partially through the modulation of the synthesis of melanotrophic factors in keratinocyte.

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Activation of the NF-$\kappa$B p50/p65 Complex in Human Lung Cancer Cell Lines (인체 폐암세포주에서 NF-$\kappa$B p50/p65 Complex의 활성화)

  • Choi, Hyung-Seok;Yoo, Chul-Gyu;Lee, Choon-Taek;Kim, Young-Whan;Han, Sung-Koo;Shim, Young-Soo
    • Tuberculosis and Respiratory Diseases
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    • v.46 no.2
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    • pp.185-194
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    • 1999
  • Background: NF-$\kappa$B is a characteristic transcriptional factor whose functional activity is determined by post-translational modification of protein and subsequent change of subcellular localization. The involvement of the NF-$\kappa$B family of the transcription factors in the control of such vital cellular functions as immune response, acute phase reaction, replication of certain viruses and development and differentiation of cells has been clearly documented in many previous studies. Several recent observations have suggested that the NF-$\kappa$B might also be involved in the carcinogenesis of some hematological and solid tumors. Investigating the possibility that members of the NF-$\kappa$B family participate in the molecular control of malignant cell transformation could provide invaluable information on both molecular pathogenesis and cancer-related gene therapy. Method: To determine the expression patterns and functional roles of NF-$\kappa$B family transcription factors in human lung cancer cell lines NCI-H792, NCI-H709, NCI-H226 and NCI-H157 were analysed by western blot, using their respective antibodies. The nuclear and the cytoplasmic fraction of protein extract of these cell lines were subsequently obtained and NF-$\kappa$B expression in each fraction was again determined by western blot analysis. The type of NF-$\kappa$B complex present in the cells was determined by immunoprecipitation. To detect the binding ability of cell-line nuclear extracts to the KB consensus oligonucleotide, electrophoretic mobility shift assay(EMSA) was performed. Results: In the cultured human lung cancer cell lines tested, transcription factors of the NF-$\kappa$B family, namely the p50 and p65 subunit were expressed and localized in the nuclear fraction of the cellular extract by western blot analysis and immunocytochemistry. Immunoprecipitation assay showed that in the cell, the p50 and p65 subunits made NF-$\kappa$B complex. Finally it was shown by Electrophoretic Mobility Shift Assay(EMSA) that nuclear extracts of lung cancer cell lines are able to bind to NF-$\kappa$B consensus DNA sequences. Conclusion: These data suggest that in human lung cancer cell lines the NF-$\kappa$B p50/p65 complex might be activated. and strengthen the hypothesis that NF-$\kappa$B family transcription factors might be involved in the carcinogenesis of human lung cancer.

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Arsenic Trioxide Induces Apoptosis and Incapacitates Proliferation and Invasive Properties of U87MG Glioblastoma Cells through a Possible NF-κB-Mediated Mechanism

  • Ghaffari, Seyed H.;Yousefi, Meysam;Dizaji, Majid Zaki;Momeny, Majid;Bashash, Davood;Zekri, Ali;Alimoghaddam, Kamran;Ghavamzadeh, Ardeshir
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.3
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    • pp.1553-1564
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    • 2016
  • Identification of novel therapeutics in glioblastoma remains crucial due to the devastating and infiltrative capacity of this malignancy. The current study was aimed to appraise effect of arsenic trioxide (ATO) in U87MG cells. The results demonstrated that ATO induced apoptosis and impeded proliferation of U87MG cells in a dose-dependent manner and also inhibited classical NF-${\kappa}B$ signaling pathway. ATO further upregulated expression of Bax as an important proapoptotic target of NF-${\kappa}B$ and also inhibited mRNA expression of survivin, c-Myc and hTERT and suppressed telomerase activity. Moreover, ATO significantly increased adhesion of U87MG cells and also diminished transcription of NF-${\kappa}B$ down-stream targets involved in cell migration and invasion, including cathepsin B, uPA, MMP-2, MMP-9 and MMP-14 and suppressed proteolytic activity of cathepsin B, MMP-2 and MMP-9, demonstrating a possible mechanism of ATO effect on a well-known signaling in glioblastoma dissemination. Taken together, here we suggest that ATO inhibits survival and invasion of U87MG cells possibly through NF-${\kappa}B$-mediated inhibition of survivin and telomerase activity and NF-${\kappa}B$-dependent suppression of cathepsin B, MMP-2 and MMP-9.

Sulforaphane Inhibits Ultraviolet B-induced Matrix Metalloproteinase Expression in Human Dermal Fibroblasts

  • Lee, Sam Youn;Moon, Sun Rock
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.26 no.6
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    • pp.922-928
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    • 2012
  • Sulforaphane [1-isothiocyanato-4-(methylsulfinyl)-butane] is one of the most abundant isothiocyanates in some cruciferous vegetables, especially broccoli. Sulforaphaene has been shown to exhibit many pharmacological activities, including anti-oxidant, anti-inflammatory and anti-microbial activities. However, the anti-skin photoaging effects of sulforaphane have not yet been reported. In the present study, we investigated the inhibitory effects of sulforaphane on MMP-1 and -3 expressions of the human dermal fibroblasts via various in vitro experiments and elucidated the pathways of inhibition. Western blot analysis and real-time PCR revealed sulfiraphane inhibited UVB-induced MMP-1 and -3 expressions in a dose-dependent manner. UVB strongly activated nuclear factor-${\kappa}B$ (NF-${\kappa}B$) activity, which was determined by NF-${\kappa}B$ DNA binding activity. UVB-induced NF-${\kappa}B$ activation and MMP expression were completely blocked by sulforphane. These findings suggest that sulforaphane could prevent UVB-induced MMPs expressions through inhibition of NF-${\kappa}B$ activation.

Nuclear Factor-κB(NF-κB) Activity and Levels of IL-6, IL-8 and TNF-α in Induced Sputum in the Exacerbation and Recovery of COPD Patients (만성폐쇄성폐질환의 급성악화와 회복기에서 유도객담 내 Nuclear Factor-κB(NF-κB)의 활성도와 IL-6, IL-8 및 TNF-α의 농도 변화)

  • Song, So Hyang;Kim, Chi Hong;Kwon, Soon Seog;Kim, Young Kyoon;Kim, Kwan Hyoung;Moon, Hwa Sik;Song, Jeong Sup;Park, Sung Hak
    • Tuberculosis and Respiratory Diseases
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    • v.58 no.2
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    • pp.152-159
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    • 2005
  • Background : Exacerbations of chronic obstructive pulmonary disease (COPD) are thought to be associated with increased airway inflammation, and the $NF-{\kappa}B$ is known to be an indicator of cellular activation and of inflammatory mediator production. This study was undertaken to investigate the change of cytokine characteristics and $NF-{\kappa}B$ activity in induced sputum of COPD patients during exacerbation and recovery of the disease. Methods : Sputum induction was performed in 37 patients with COPD during exacerbation and during recovery and in 15 healthy subjects. Cell counts, levels of IL-6, IL-8 and $TNF-{\alpha}$ in induced sputum and NF-kB activity in macrophage of induced sputum were measured. Results : Patients with COPD showed significantly increased levels of IL-6, IL-8 and $TNF-{\alpha}$(p<0.01) and increased $NF-{\kappa}B$ activity in induced sputum(p<0.05) as compared with control subjects. Level of IL-8 during exacerbation of COPD decreased significantly during recovery(p<0.05). $NF-{\kappa}B$ activity and levels of IL-6 and $TNF-{\alpha}$ tended to be decreased during recovery, but not siginificantly. Conclusion : Activation of $NF-{\kappa}B$ and increased levels of IL-6, IL-8 and $TNF-{\alpha}$ were thought to be associated with pathogenesis and exacerbations of COPD.

Hepatitis Delta Virus Large Antigen Sensitizes to TNF-α-Induced NF-κB Signaling

  • Park, Chul-Yong;Oh, Sang-Heun;Kang, Sang Min;Lim, Yun-Sook;Hwang, Soon B.
    • Molecules and Cells
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    • v.28 no.1
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    • pp.49-55
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    • 2009
  • Hepatitis delta virus (HDV) infection causes fulminant hepatitis and liver cirrhosis. To elucidate the molecular mechanism of HDV pathogenesis, we examined the effects of HDV viral proteins, the small hepatitis delta antigen (SHDAg) and the large hepatitis delta antigen (LHDAg), on $NF-{\kappa}B$ signaling pathway. In this study, we demonstrated that $TNF-{\alpha}-induced$ $NF-{\kappa}B$ transcriptional activation was increased by LHDAg but not by SHDAg in both HEK293 and Huh7 cells. Furthermore, LHDAg promoted TRAF2-induced $NF-{\kappa}B$ activation. Using coimmunoprecipitation assays, we demonstrated that both SHDAg and LHDAg interacted with TRAF2 protein. We showed that isoprenylation of LHDAg was not required for the increase of $NF-{\kappa}B$ activity. We further showed that only LHDAg but not SHDAg increased the $TNF-{\alpha}-mediated$ nuclear translocation of p65. This was accomplished by activation of $I{\kappa}B_{\alpha}$ degradation by LHDAg. Finally, we demonstrated that LHDAg augmented the COX-2 expression level in Huh7 cells. These data suggest that LHDAg modulates $NF-{\kappa}B$ signaling pathway and may contribute to HDV pathogenesis.

The Effect of Cobrotoxin on $NF-{\kappa}B$ binding Activity in Raw264.7 cells

  • Yoo, Jae-Ryong;Song, Ho-Sueb
    • Journal of Acupuncture Research
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    • v.22 no.2
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    • pp.133-139
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    • 2005
  • Cobrotoxin, a venom of Vipera lebetina turanica, is a group of basic peptidescomposed of 233 amino acids with six disulfide bonds formed by twelve cysteins. NF-kB is activated by subsequent release of inhibitory IkB and translocation of p50. Since sulfhydryl group is present in kinase domain of p50 subunit of NF-kB, cobrotoxin could modify NF-kB activity by protein-protein interaction. We therefore examined effect of cobrotoxin on NF-kB activities in lipopolysaccharide (LPS) and sodium nitroprusside (SNP)-stimulated Raw 264.7 mouse macrophages. Cobrotoxin suppressed the LPS and SNP-induced release of IkB and p50 translocation resulted in inhibition of DNA binding activity of NF-kB. Inhibition of NF-kB resulted in reduction of the LPS and SNP-induced production of inflammatory mediators NO and PGE2 generation. The inhibitory effect of cobrotoxin on the NF-kB activity were blocked by addition of reducing agents dithiothreitol and glutathione. These results demonstrate that cobrotoxin inhibits activation of NF-kB, and suggest that pico to nanomolar range of cobrotoxin could inhibit the expression of genes in the NF-kB signal pathway.

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Relationship of Inhibitory Effects of Dichroa febrifuga and $IKK{\gamma}$ on the Activation of $NF-{\kappa}B$ (상산의 $NF-{\kappa}B$ 활성억제작용과 $IKK{\gamma}$의 연관성 연구)

  • Choi, Byung-Tae;Lee, Yong-Tae;Hwang, Jang-Sun;Moon, Hae-In;Lee, Kyung-Soo;An, Won-Gun;Kim, Dong-Wan
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.20 no.3
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    • pp.651-656
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    • 2006
  • Activation of $NF-{\kappa}B$ is known to be a trigger of various cellular disorders including inflammatory and autoimmune diseases such as rheumatoid arthritis. Numerous approaches are ongoing within laboratories to identify potential therapeutic agents which inhibit the $NF-{\kappa}B$ activation. In this study, we have tested the inhibitory effects of five traditional medicines on the activation of $NF-{\kappa}B$ by NIK. Among three medicines which exhibited inhibitory effect on the expression of $NF-{\kappa}B$ repoter plasmid, we investigated further the inhibitory mechanism of Dichroa febrifuga in connection with IKKY activity. Wild type $IKK{\gamma}$ inhibited the $NF-{\kappa}B$ activation by NIK but the C-terminal deletion mutant of IKKY did not show the inhibitory effect, indicating that the C-terminal leucine zipper domain of $NF-{\kappa}B$ is important for the inhibition of $NF-{\kappa}B$ activation. The water extract of Dichroa febrifuga(DFE) also strongly inhibited the $NF-{\kappa}B$ activation by NIK. The inhibitory activity of DFE appeared to be independent of the expression of $IKK{\gamma}$, suggesting that the pathways of inhibition by Dichroa febrifuga and $IKK{\gamma}$ are different. Our results suggest that Dichroa febrifuga can be used as a medicine for inhibition of the $NF-{\kappa}B$ activation in a wide range of cells without relation to the expression of $IKK{\gamma}$.

Gliotoxin from the marine fungus Aspergillus fumigatus induces apoptosis in HT1080 fibrosarcoma cells by downregulating NF-κB

  • Kim, Young-Sang;Park, Sun Joo
    • Fisheries and Aquatic Sciences
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    • v.19 no.9
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    • pp.35.1-35.6
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    • 2016
  • Gliotoxin has been recognized as an immunosuppressive agent for a long time. Recently, it was reported to have antitumor properties. However, the mechanisms by which it inhibits tumors remain unclear. Here, we showed that gliotoxin isolated from the marine fungus Aspergillus fumigatus inhibited proliferation and induced apoptosis in HT1080 human fibrosarcoma cells. Gliotoxin repressed phosphorylation-dependent degradation of $I{\kappa}B-{\alpha}$, an antagonist of nuclear factor kappa B ($NF-{\kappa}B$), which is a known tumor-promoting factor. This coincided with a decrease in nuclear import of $NF-{\kappa}B$, suggesting its signaling activity was impaired. Moreover, gliotoxin increased intracellular reactive oxygen species (ROS). Since ROS have been known to inhibit $NF-{\kappa}B$, this may also contribute to gliotoxin's antitumorigenic effects. These results suggest that gliotoxin suppressed the activation of $NF-{\kappa}B$ by inhibiting phosphorylation and degradation of $I{\kappa}B-{\alpha}$ and by increasing ROS, which resulted in apoptosis of HT1080 cells. Cumulatively, gliotoxin is a promising candidate antagonist of $NF-{\kappa}B$, and it should be investigated for its possible use as a selective inhibitor of human fibrosarcoma cells.

Lactobacillus acidophilus Strain Suppresses the Transcription of Proinflammatory-Related Factors in Human HT-29 Cells

  • Chen, Kun;Liang, Nailong;Luo, Xuegang;Zhang, Tong-Cun
    • Journal of Microbiology and Biotechnology
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    • v.23 no.1
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    • pp.64-68
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    • 2013
  • Previous studies have shown that lactic acid bacteria can inhibit inflammatory responses, but the mechanisms are very little known. In this study, transaction and expression of three proinflammatory factors, iNOS, PTGS-2, and IL8, which are closely related to the inflammatory response, were investigated by luciferase reporter assay and RTPCR in HT-29 cells treated by Lactobacillus acidophilus. The results showed that the live L. acidophilus sharply down-regulated the transcription of these three genes. Because there was a NF-${\kappa}B$ binding site located at -265 bp, -225 bp, and -95 bp upstream of the iNOS, PTGS-2, and IL8 promoters, respectively, we further addressed the effects of NF-${\kappa}B$ on transaction of the three promoters by cotransfection. As was expected, NF-${\kappa}Bs$ remarkably upregulated the activity of the reporter gene and, no effect of NF-${\kappa}B$s on IL-8 promoter transaction was found after NF-${\kappa}B$ binding site mutation of the IL8 promoter in HT-29 cells. In conclusion, the live L. acidophilus decreased the transcriptional activity of NF-${\kappa}B$ and, in turn, inhibited the transaction of NF-${\kappa}B$ on the three proinflammatory factors mentioned above.