• Title/Summary/Keyword: NF-kB activation

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A Novel Synthetic Compound, YH-1118, Inhibited LPS-Induced Inflammatory Response by Suppressing IκB Kinase/NF-κB Pathway in Raw 264.7 Cells

  • Yun, Chang Hyun;Jang, Eun Jung;Kwon, Soon Cheon;Lee, Mee-Young;Lee, Sangku;Oh, Sei-Ryang;Lee, Hyeong-Kyu;Ahn, Kyung-Seop;Lee, Ho-Jae
    • Journal of Microbiology and Biotechnology
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    • v.25 no.7
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    • pp.1047-1055
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    • 2015
  • For the search of a potent first-in-class compound to inactivate macrophages responsible for inflammatory responses, in the present study, we investigated the anti-nflammatory effects of YH-1118, a novel synthetic compound, in a lipopolysaccharide (LPS)-stimulated mouse macrophage cell line, Raw 264.7. YH-1118 inhibited LPS-induced nitric oxide (NO) production and inducible NO synthase (iNOS) expression at both the protein and mRNA levels. The suppression of LPS-induced iNOS expression by YH-1118 was mediated via nuclear factor kappa B (NF-κB), but not activator protein-1 (AP-1) transcription factor. This was supported by the finding that YH-1118 attenuated the phosphorylation of inhibitor of κBα (IκBα) and nuclear translocation and DNA binding activity of NF-κB. Through the mechanisms that YH-1118 inhibited the activation of IκB kinases (IKKs), upstream activators of NF-κB, or p38 MAPK, YH-1118 significantly suppressed LPS-induced production of pro-inflammatory cytokines, tumor necrosis factor-α, interleukin-1β (IL-1β), and IL-6 (p < 0.05). In conclusion, our results suggest that YH-1118 inhibits LPS-induced inflammatory responses by blocking IKK and NF-κB activation in macrophages, and may be a therapeutic candidate for the treatment of various inflammatory diseases.

Expression of Nuclear Factor Kappa B (NF-κB) as a Predictor of Poor Pathologic Response to Chemotherapy in Patients with Locally Advanced Breast Cancer

  • Prajoko, Yan Wisnu;Aryandono, Teguh
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.2
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    • pp.595-598
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    • 2014
  • Background: NF-${\kappa}B$ inhibits apoptosis through induction of antiapoptotic proteins and suppression of proapoptotic genes. Various chemotherapy agents induce NF-${\kappa}B$ translocation and target gene activation. We conducted the present study to assess the predictive value of NF-${\kappa}B$ regarding pathologic responses after receiving neoadjuvant chemotherapy. Materials and Methods: We enrolled 131 patients with locally advanced invasive ductal breast carcinoma. Immunohistochemistry (IHC) was used to detect NF-${\kappa}B$ expression. Evaluation of pathologic response was elaborated with the Ribero classification. Results: Expression of NF-${\kappa}B$ was significantly associated with poor pathological response (p=0.02). From the multivariate analysis, it was found that the positive expression of NF-${\kappa}B$ yielded RR=1.74 (95%CI 0.77 to 3.94). Conclusions: NF-${\kappa}B$ can be used as a predictor of poor pathological response after neoadjuvant chemotherapy.

Inhibitory Effect of the Rodgersia podophylla Leave Extracts against Cell Proliferation through Activation of NF-κB in Human Colorectal Cancer Cells (도깨비부채 잎 추출물의 NF-κB 활성화를 통한 대장암 세포 HCT116에 대한 세포생육 억제활성)

  • Kim, Jeong Dong;Jeong, Jin Boo
    • Korean Journal of Plant Resources
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    • v.33 no.5
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    • pp.460-466
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    • 2020
  • In this study, we evaluated the anti-cancer activity and potential molecular mechanism of 70% ethanol extracts of leaves from Rodgersia podophylla against human colorectal cancer cells, HCT116. RPL dose-dependently decreased the cell viability through RPL-induced apoptosis in HCT116 cells. RPL induced inactivation the nuclear factor κB(NF-κB) through blocking IκB-α degradtion and P65 nuclear accumulation. The inhibition of GSK3β by LiCl attenuated RP-L-mediated NF-κB signaling inactivation. In addition, RP-L induced GSK3β activation. Based on these findings, RPL may be a potential candidate for the development of chemopreventive or therapeutic agents for human colorectal cancer.

The Anti-inflammatory Mechanism of Blueberry is through Suppression of NF-kB/Caspase-1 Activation in LPS-induced RAW264.7 Cells

  • Mi-Ok Yang;Noh-Yil Myung
    • Korean Journal of Plant Resources
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    • v.37 no.3
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    • pp.256-262
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    • 2024
  • Blueberry (BB), fruit of Vacciniumi, has been hailed as an antioxidant superfood. BB is a rich source of vitamins, minerals, flavonoids, phenolic acids and known to have a variety of pharmacological actions. The purpose of this work is to clarify the anti-inflammatory mechanism of BB in lipopolysaccharide (LPS)-activated RAW264.7 macrophage. We explored the effects of BB on the production of inflammatory cytokines, prostaglandin E2 (PGE2) and expression of cyclooxygenase (COX)-2 in LPS-activated RAW264.7 macrophage. Moreover, to investigate the molecular mechanisms by BB, we evaluated whether BB modulate nuclear factor-kappa B (NF)-kB pathway and caspase- 1 activation. The findings of this work demonstrated that BB alleviated the LPS-enhanced inflammatory cytokines and PGE2, as well as COX-2 levels. Additionally, we demonstrated that the anti-inflammatory mechanism of BB occurs due to the attenuation of IκB-α degradation, NF-kB translocation and caspase-1 activation. Conclusively, these findings provide evidence that BB may be useful agents in the treatment of inflammation.

Curcumin and its Analogues (PGV-0 and PGV-1) Enhance Sensitivity of Resistant MCF-7 Cells to Doxorubicin through Inhibition of HER2 and NF-kB Activation

  • Meiyanto, Edy;Putri, Dyaningtyas Dewi Pamungkas;Susidarti, Ratna Asmah;Murwanti, Retno;Sardjiman, Sardjiman;Fitriasari, Aditya;Husnaa, Ulfatul;Purnomo, Hari;Kawaichi, Masashi
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.1
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    • pp.179-184
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    • 2014
  • Chemoresistance of breast cancer to doxorubicin is mediated mainly through activation of NF-kB and over expression of HER2. Curcumin and its analogues (PGV-0 and PGV-1) exert cytotoxic effects on T47D breast cancer cells. Suppression of NF-kB activation is suggested to contribute to this activity. The present study aimed to explore the effects of curcumin, PGV-0, and PGV-1 singly and in combination with doxorubicin on MCF-7/Dox cells featuring over-expression of HER2. In MTT assays, curcumin, PGV-0, and PGV-1 showed cytotoxicity effects against MCF-7/Dox with IC50 values of $80{\mu}M$, $21{\mu}M$, and $82{\mu}M$ respectively. These compounds increased MCF-7/Dox sensitivity to doxorubicin. Cell cycle distribution analysis exhibited that the combination of curcumin and its analogues with Dox increased sub G-1 cell populations. Curcumin and PGV-1 but not PGV-0 decreased localization of p65 into the nucleus induced by Dox, indicating that activation of NF-kB was inhibited. Molecular docking of curcumin, PGV-0, and PGV-1 demonstrated high affinity to HER2 at ATP binding site. This interaction were directly comparable with those of ATP and lapatinib. These findings suggested that curcumin, PGV-0 and PGV-1 enhance the Dox cytotoxicity to MCF-7 cells through inhibition of HER2 activity and NF-kB activation.

Sulfuretin Inhibits Ultraviolet B-induced MMP Expression in Human Dermal Fibroblasts

  • So, Hong-Seob;Kim, Seung-Hoon;Lee, Young-Rae
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.25 no.3
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    • pp.533-539
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    • 2011
  • Sulfuretin is one of the main flavonoids produced by Rhusverniciflua. Sulfuretin has been shown to exhibit many pharmacological activities including anti-oxidant, anti-obesity, anti-inflammatory and anti-mutagenic activities. However, the anti-skin photoaging effects of sulfuretin has not yet been reported. In the present study, we investigated the inhibitory effect of sulfuretin on the expression levels of MMP-1 and -3 in the human dermal fibroblast cells. Western blot analysis and real-time PCR revealed sulfuretin inhibited UVB-induced MMP-1 and -3 expressions in a dose-dependent manner. UVB-induced MAPK/NF-${\kappa}B$/p50 activation and MMP expression were completely blocked by pretreatment of sulfuretin. Taken together, sulfuretin could prevent UVB-induced MMP expressions through inhibition of MAPK/NF-${\kappa}B$/p50 activation.

Inhibition of Homodimerization of Toll-like Receptor 4 by 6-Shogaol

  • Ahn, Sang-Il;Lee, Jun-Kyung;Youn, Hyung-Sun
    • Molecules and Cells
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    • v.27 no.2
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    • pp.211-215
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    • 2009
  • Toll-like receptors (TLRs) play a critical role in sensing microbial components and inducing innate immune and inflammatory responses by recognizing invading microbial pathogens. Lipopolysaccharide-induced dimerization of TLR4 is required for the activation of downstream signaling pathways including nuclear factor-kappa B ($NF-{\kappa}B$). Therefore, TLR4 dimerization may be an early regulatory event in activating ligand-induced signaling pathways and induction of subsequent immune responses. Here, we report biochemical evidence that 6-shogaol, the most bioactive component of ginger, inhibits lipopolysaccharide-induced dimerization of TLR4 resulting in the inhibition of $NF-{\kappa}B$ activation and the expression of cyclooxygenase-2. Furthermore, we demonstrate that 6-shogaol can directly inhibit TLR-mediated signaling pathways at the receptor level. These results suggest that 6-shogaol can modulate TLR-mediated inflammatory responses, which may influence the risk of chronic inflammatory diseases.

Cardamonin Inhibits the Expression of Inducible Nitric Oxide Synthase Induced by TLR2, 4, and 6 Agonists

  • Kim, Ah-Yeon;Shim, Hyun-Jin;Kim, Su-Yeon;Heo, Sung-Hye;Youn, Hyung-Sun
    • Biomedical Science Letters
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    • v.24 no.2
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    • pp.102-107
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    • 2018
  • Toll-like receptors (TLRs) play an important role for host defense against invading pathogens. The activation of TLRs signaling leads to the activation of $NF-{\kappa}B$ and the expression of pro-inflammatory gene products such as cytokines and inducible nitric oxide synthase (iNOS). To evaluate the therapeutic potential of cardamonin, which is a naturally occurring chalcone from Alpinia species (zingiberaceous plant species), $NF-{\kappa}B$ activation and iNOS expression induced by MALP-2 (TLR2 and TLR6 agonist) or LPS (TLR4 agonist) were examined. Cardamonin inhibited the activation of $NF-{\kappa}B$ induced by MALP-2 or LPS. Cardamonin also suppressed the iNOS expression induced by MALP-2 or LPS. These results suggest that cardamonin has the specific mechanism for anti-inflammatory responses by regulating of TLRs signaling pathway.

Induction of nuclear factor-${\kappa}B$ activation through TAK1 and NIK by diesel exhaust particles in L2 cell lines

  • Yun, Young-Pil;Joo, Jin-Deok;Lee, Joo-Yong;Nam, Hae-Yun;Kim, Young-Hoon;Lee, Kweon-Haeng;Lim, Cheol-Soo;Kim, Hyung-Jung;Lim, Yong-Gul;Lim, Young
    • Proceedings of the Korean Society of Toxicology Conference
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    • 2005.05a
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    • pp.85-90
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    • 2005
  • Diesel exhaust Particles (DEPs) are known to induce allergic responses in airway epithelial cells, such as the production of various cytokines via nuclear factor-kappa B ($NF-{\kappa}B$). However. the intracellular signal transduction pathways underlying this phenomenon have not been fully examined. This study showed that DEP induced $NF-{\kappa}B$ activity via transforming growth factor-${\beta}$ activated kinase 1 (TAK1) and $NF-{\kappa}B$-inducing kinase (NIK) in L2 rat lung epithelial cells. DEP induced the $NF-{\kappa}B$ dependent reporter activity approximately two-to three-fold in L2 cells. However, this effect was abolished by the expression of the dominant negative forms of TAK1 or NIK. Furthermore, it was shown that DEP induced TAK1 phosphorylation in the L2 cells. These results suggest that TAK1 and NIK are important mediators of DEP-induced $NF-{\kappa}B$ activation.

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The Proteasome Inhibitor MG132 Sensitizes Lung Cancer Cells to TRAIL-induced Apoptosis by Inhibiting NF-κ Activation (폐암세포주에서 NFκ 활성 억제를 통한 Proteasome 억제제 MG132의 TRAIL-유도성 Apoptosis 감작 효과)

  • Seo, Pil Won;Lee, Kye Young
    • Tuberculosis and Respiratory Diseases
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    • v.65 no.6
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    • pp.476-486
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    • 2008
  • Background: TRAIL (TNF-related apoptosis inducing ligand) is a newly identified member of the TNF gene family which appears to have tumor-selective cytotoxicity due to the distinct decoy receptor system. TRAIL has direct access to caspase machinery and induces apoptosis regardless of p53 phenotype. Therefore, TRAIL has a therapeutic potential in lung cancer which frequently harbors p53 mutation in more than 50% of cases. However, it was shown that TRAIL also could activates $NF-{\kappa}B$ in some cell lines which might inhibit TRAIL-induced apoptosis. This study was designed to investigate whether TRAIL can activate $NF-{\kappa}B$ in lung cancer cell lines relatively resistant to TRAIL-induced apoptosis and inhibition of $NF-{\kappa}B$ activation using proteasome inhibitor MG132 which blocks $I{\kappa}B{\alpha}$ degradation can sensitize lung cancer cells to TRAIL-induced apoptosis. Methods: A549 (wt p53) and NCI-H1299 (null p53) lung cancer cells were used and cell viability test was done by MTT assay. Apoptosis was confirmed with Annexin V assay followed by FACS analysis. To study $NF-{\kappa}B$-dependent transcriptional activation, a luciferase reporter gene assay was used after making A549 and NCI-H1299 cells stably transfected with IgG ${\kappa}-NF-{\kappa}B$ luciferase construct. To investigate DNA binding of $NF-{\kappa}B$ activated by TRAIL, electromobility shift assay was used and supershift assay was done using anti-p65 antibody. Western blot was done for the study of $I{\kappa}B{\alpha}$ degradation. Results: A549 and NCI-H1299 cells were relatively resistant to TRAIL-induced apoptosis showing only 20~30% cell death even at the concentration 100 ng/ml, but MG132 ($3{\mu}M$) pre-treatment 1 hour prior to TRAIL addition greatly increased cell death more than 80%. Luciferase assay showed TRAIL-induced $NF-{\kappa}B$ transcriptional activity in both cell lines. Electromobility shift assay demonstrated DNA binding complex of $NF-{\kappa}B$ activated by TRAIL and supershift with p65 antibody. $I{\kappa}B{\alpha}$ degradation was proven by western blot. MG132 completely blocked both TRAIL-induced $NF-{\kappa}B$ dependent luciferase activity and DNA binding of $NF-{\kappa}B$. Conclusion: This results suggest that inhibition of $NF-{\kappa}B$ can be a potentially useful strategy to enhance TRAIL-induced tumor cell killing in lung cancer.