• 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 $IKK{\gamma}$.

• The Korean Journal of Physiology and Pharmacology
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• v.7 no.4
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• pp.239-246
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• 2003

The expression of cyclooxygenase-2 (COX-2) is a characteristic response to inflammation and can be inhibited with sodium salicylate. $TNF-{\alpha}$ plus $IFN-{\gamma}$ can induce extracellular signal-regulated kinase (ERK), IKK, $I{\kappa}B$ degradation and NF-${\kappa}B$ activation. The inhibition of the ERK pathway with selective inhibitor, PD098059, blocked cytokine-induced COX-2 expression and $PGE_2$ release. Salicylate treatment inhibited COX-2 expression induced by $TNF-{\alpha}$/$IFN-{\gamma}$ and regulated the activation of ERK, IKK and $I{\kappa}B$ degradation and subsequent NF-${\kappa}B$ activation in MC3T3E1 osteoblasts. Furthermore, antioxidants such as catalase, N-acetyl-cysteine or reduced glutathione attenuated COX-2 expression in combined cytokines-treated cells, and also inhibited the activation of ERK, IKK and NF-${\kappa}B$ in MC3T3E1 osteoblasts. In addition, $TNF-{\alpha}$/$IFN-{\gamma}$ stimulated ROS release in the osteoblasts. However, salicylate had no obvious effect on ROS release in DCFDA assay. The results showed that salicylate inhibited the activation of ERK and IKK, $I{\kappa}B$ degradation and NF-${\kappa}B$ activation independent of ROS release and suggested that salicylate exerts its anti-inflammatory action in part through inhibition of ERK, IKK, $I{\kappa}B$, $NF-{\kappa}B$ and resultant COX-2 expression pathway.

• CELLMED
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• v.2 no.3
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• pp.27.1-27.6
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• 2012

Red ginseng, which has a variety of biological and pharmacological activities including antioxidant, anti-inflammatory, antimutagenic and anticarcinogenic effects, has been used for thousands of years as a general tonic in traditional oriental medicine. Here, we tested the immune regulatory activities of hydrolyzed red ginseng by malted barley (HRG) on the expressions of receptor interacting proteins (Rip) 2 and $I{\kappa}B$ kinase-beta (IKK-${\beta}$) in mouse peritoneal macrophages. We show that HRG increased the activations of Rip 2 and IKK-${\beta}$ for the first time. When HRG was used in combination with recombinant interferon-${\gamma}$ (rIFN-${\gamma}$), there was a marked cooperative induction of nitric oxide (NO) production. The increased expression of inducible NO synthase from rIFN-${\gamma}$ plus HRG-stimulated cells was almost completely inhibited by pre-treatment with pyrrolidine dithiocarbamate (PDTC), an inhibitor of nuclear factor-${\kappa}B$ (NF-${\kappa}B$). In addition, the treatment of peritoneal macrophages with rIFN-${\gamma}$ plus HRG caused significant increases in tumor necrosis factor (TNF)-${\alpha}$ mRNA expression and production. Because NO and TNF-${\alpha}$ play an important role in the immune function and host defense, HRG treatment can modulate several aspects of the host defense mechanisms as a result of the stimulations of the inducible nitric oxide synthase and NF-${\kappa}B$. In conclusion, our findings demonstrate that HRG increases the productions of NO and TNF-${\alpha}$ from rIFN-${\gamma}$-primed macrophages and suggest that Rip2/IKK-${\beta}$ plays a critical role in mediating these immune regulatory effects of HRG.

• Molecules and Cells
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• v.26 no.2
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• pp.175-180
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• 2008

$I{\kappa}B$ kinase (IKK), the pivotal kinase in signal-dependent activation of nuclear factor-${\kappa}B$ (NF-${\kappa}B$), is composed of multiple protein components, including IKK ${\alpha}/{\beta}/{\gamma}$ core subunits. To investigate the regulation of the IKK complex, we immunoaffinity purified the IKK complex, and by MALDI-TOF mass spectrometry identified a splice variant of zinc finger protein 268 (ZNF268) as a novel IKKinteracting protein. Both the full-length and the spliced form of the ZNF268 protein were detected in a variety of mammalian tissues and cell lines. The genes were cloned and expressed by in vitro transcription/translation. Several deletion derivatives, such as KRAB domain (KRAB) on its own, the KRAB/spacer/4-zinc fingers (zF4), and the spacer/4-zinc fingers (zS4), were ectopically expressed in mammalian cells and exhibited had different subcellular locations. The KRAB-containing mutants were restricted to the nucleus, while zS4 was localized in the cytosol. TNF-${\alpha}$-induced NF-${\kappa}B$ activation was examined using these mutants and only zS4 was found to stimulate activation. Collectively, the results indicate that a spliced form of ZNF268 lacking the KRAB domain is located in the cytosol, where it seems to play a role in TNF-${\alpha}$-induced NF-${\kappa}B$ activation by interacting with the IKK complex.

• The Korean Journal of Physiology and Pharmacology
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• v.22 no.4
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• pp.369-377
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• 2018

Spinal tuberculosis (ST) is the tuberculosis caused by Mycobacterium tuberculosis (Mtb) infections in spinal curds. Isoliquiritigenin (4,2',4'-trihydroxychalcone, ISL) is an anti-inflammatory flavonoid derived from licorice (Glycyrrhiza uralensis), a Chinese traditional medicine. In this study, we evaluated the potential of ISL in treating ST in New Zealand white rabbit models. In the model, rabbits (n=40) were infected with Mtb strain H37Rv or not in their $6^{th}$ lumbar vertebral bodies. Since the day of infection, rabbits were treated with 20 mg/kg and 100 mg/kg of ISL respectively. After 10 weeks of treatments, the adjacent vertebral bone tissues of rabbits were analyzed through Hematoxylin-Eosin staining. The relative expression of Monocyte chemoattractant protein-1 (MCP-1/CCL2), transcription factor ${\kappa}B$ ($NF-{\kappa}B$) p65 in lymphocytes were verified through reverse transcription quantitative real-time PCR (RT-qPCR), western blotting and enzyme-linked immunosorbent assays (ELISA). The serum level of interleukin (IL)-2, IL-4, IL-10 and interferon ${\gamma}$ ($IFN-{\gamma}$) were evaluated through ELISA. The effects of ISL on the phosphorylation of $I{\kappa}B{\alpha}$, $IKK{\alpha}/{\beta}$ and p65 in $NF-{\kappa}B$ signaling pathways were assessed through western blotting. In the results, ISL has been shown to effectively attenuate the granulation inside adjacent vertebral tissues. The relative level of MCP-1, p65 and IL-4 and IL-10 were retrieved. $NF-{\kappa}B$ signaling was inhibited, in which the phosphorylation of p65, $I{\kappa}B{\alpha}$ and $IKK{\alpha}/{\beta}$ were suppressed whereas the level of $I{\kappa}B{\alpha}$ were elevated. In conclusion, ISL might be an effective drug that inhibited the formation of granulomas through downregulating MCP-1, $NF-{\kappa}B$, IL-4 and IL-10 in treating ST.

• Journal of Life Science
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• v.32 no.3
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• pp.241-248
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• 2022

NF-κB acts as a critical transcription factor in inflammation and innate immunity, and it is also closely involved in cell survival and tumorigenesis via induction of anti-apoptotic genes. In these processes, NF-κB cooperates with multiple other signaling molecules and pathways, and although many studies have demonstrated that Hsp90 regulates NF-κB activity, the exact mechanism is unclear. In this study, we investigated the relationship between Hsp90 and IKKγ in the regulation of NF-κB using expression plasmids of IKK complex components. Wild-type and deletion mutants of IKKγ were expressed together with Hsp90, and the combined regulatory effect of Hsp90 and IKKγ on NF-κB activation was assayed. The results show that Hsp90 activates NF-κB by promoting the phosphorylation and degradation of IκBα and that activation of NF-κB by NIK and LPS was increased by Hsp90. IKKγ elevated the effect of Hsp90 on NF-κB activation by increasing phosphorylation and degradation of IκBα. The positive regulation on NF-κB by Hsp90 and IKKγ was also proved in analysis with IKKβ-EE, the constitutively active form of IKKβ. In experiments with the deletion mutants of IKKγ, the N-terminal IKKβ binding domain, C-terminal leucine zipper, and zinc finger domains of IKKγ were found not necessary for the positive regulation of NF-κB activity. Additionally, the expression of pro-inflammatory cytokines was synergistically elevated by Hsp90 and IKKγ. These results indicate that inhibiting the interaction between Hsp90 and IKKγ is a possible strategic method for controlling NF-κB and related diseases.

• BMB Reports
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• v.48 no.3
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• pp.172-177
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• 2015

Upregulation of pro-inflammatory mediators contributes to ${\beta}$-cell destruction and enhanced infiltration of immune cells into pancreatic islets during development of type 1 diabetes mellitus. In this study, we examined the regulatory effects and the mechanisms of action of celastrol against cytotoxicity and pro-inflammatory immune responses in the RINm5F rat pancreatic ${\beta}$-cell line stimulated with a combination of interleukin-1 beta, tumor necrosis factor-alpha, and interferon-${\gamma}$. Celastrol significantly restored cytokine-induced cell death and significantly inhibited cytokine-induced nitric oxide production. In addition, the protective effect of celastrol was correlated with a reduction in pro-inflammatory mediators, such as inducible nitric oxide synthase, cyclooxygenase-2, and CC chemokine ligand 2. Furthermore, celastrol significantly suppressed cytokine-induced signaling cascades leading to nuclear factor kappa B (NF-${\kappa}B$) activation, including $I{\kappa}B$-kinase (IKK) activation, $I{\kappa}B$ degradation, p65 phosphorylation, and p65 DNA binding activity. These results suggest that celastrol may exert its cytoprotective activity by suppressing cytokine-induced expression of pro-inflammatory mediators by inhibiting activation of NF-${\kappa}B$ in RINm5F cells.

• Journal of Biomedical Engineering Research
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• v.44 no.6
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• pp.443-449
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• 2023

The purpose of this study was to observe cell death in human keratinocytes stimulated against the infectious cytokines TNF-α and IFN-γ, and to observe the expression of Phospho-NF-κB due to phosphorylation of IkB to confirm the mechanism of inhibiting the expression of inflammatory cytokines. As a result of cell viability analysis, differences in PEMF stimulation time were observed little by little after 1 hour, 3 hours, 6 hours, 12 hours, 24 hours, and 48 hours, but there was no statistical significance according to PEMF stimulation time for each time (p>0.05). No significant difference was observed in the total amount of NF-κB present in the cytoplasm and nucleus, but a significant decrease in the expression of phosphorylated NF-κB was observed in the group exposed to PEMF stimulation for 24 hours (^*p<0.05). The expression of IL-1β was observed in all inflammation-induced groups, and the concentration of IL-1β compared to α-Tubulin expression was reduced by about 54% in the PEMF-stimulated group for 24 hours compared to the control group (^***p<0.001). As a result of the study, it is shown that PEMF stimulation does not negatively affect HaCaT cells from 0 to 48 hours and can inhibit the expression of inflammatory cytokines by inhibiting the pathway of NF-κB.