• Tuberculosis and Respiratory Diseases
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• v.49 no.3
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• pp.332-342
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• 2000

Background : The importance of pro-inflammatory cytokines, especially tumor necrosis factor $\alpha$ (INF-$\alpha$) and interleukin-1$\beta$ (IL-1$\beta$), have been extensively documented in the generation of inflammatory lung disease. Lung epithelial cells are also actively involved in initiating and maintaining inflammation by producing pro-inflammatory mediators. Understanding the mechanism of pro-inflammatory cytokine expression in lung epithelial cells is crucial to the development of new therapeutic modalities for inflammatory lung disease. Transcription of most pro-inflammatory cytokines is dependent on the activation of NF-${\kappa}B$. However, the relationship between pro-inflammatory cytokine expression and NF-${\kappa}B/I{\kappa}B$ pathway in lung epithelial cells is not clear. Methods : BEAS-2B, A549, Na-H157, NCI-H719 cells were stimulated with IL-$1{\beta}$ or TNF-$\alpha$ at various times, and then IL-8 and TNF-$\alpha$mRNA expressions were assayed by Northern blot analysis. IL-$1{\beta}$ or TNF-$\alpha$-induced NF-${\kappa}B$ activation was assessed by the nuclear translocation of p65 NF-${\kappa}B$ subunit. The degradation of $I{\kappa}B{\alpha}$ and $I{\kappa}B{\beta}$ by IL-$1{\beta}$ or TNF-$\alpha$stimulation was assayed by Western blot analysis. The phosphorylation of $I{\kappa}B{\alpha}$ was evaluated by Western blot analysis after pre-treating cells with proteasome inhibitor followed by IL-$1{\beta}$ or TNF-$\alpha$ stimulation. The basal level of IKK $\alpha$ expression was evaluated by Western blot analysis. Results: $I{\kappa}B{\alpha}$ and $I{\kappa}B{\alpha}$ was rapidly degraded after 5 minutes of incubation with IL-$1{\beta}$ or TNF-$\alpha$ in BEAS-2B, A549, and NCI-H157 cells. The activation of NF-${\kappa}B{\alpha}$ and the induction of IL-8 and TNF-$\alpha$ mRNA expression were observed by IL-$1{\beta}$ or TNF-$\alpha$ stimulation in these cells. In contrast, neither the changes in NF-${\kappa}B/I{\kappa}B$ pathway nor IL-8 and TNF-$\alpha$mRNA expression was induced by IL-$1{\beta}$ or TNF-$\alpha$ stimulation in NCI-H719 cells. IL-$1{\beta}$ and TNF-$\alpha$-induced $I{\kappa}B$ phosphorylation was observed in BEAS-2B, A549, and NCI-H157 cells, but not in NCI-H719 cells. The basal level of IKK$\alpha$ expression was not different between cell. Conclusion : NF-${\kappa}B/I{\kappa}B$ pathway plays an important role in the expression of pro-inflammatory cytokine in most lung epithelial cells. The absence of the effect on NF-${\kappa}B/I{\kappa}B$ pathway in NCI-H719 cells sæms to be due to the defect in the intracellular signal transduction pathway upstream to IKK.

• Tuberculosis and Respiratory Diseases
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• v.54 no.4
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• pp.449-458
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• 2003

Background : Cyclosporin A(CsA) and tacrolimus(FK506) have been widely used as immunosuppressants. The effects of CsA, or FK506, on the $I{\kappa}B/NF-{\kappa}B$ pathway have been shown to vary according to the cell type. However, their effects on the $I{\kappa}B/NF-{\kappa}B$ pathway have not been reported in bronchial epithelial cells. In this study, the effects of CsA and FK506 on the $I{\kappa}B/NF-{\kappa}B$ pathway in bronchial epithelial cells, monocytes, lymphocytes and alveolar macrophages were evaluated. The relationship between their effects on the $I{\kappa}B/NF-{\kappa}B$ pathway and $I{\kappa}B$ kinase(IKK) activity was also investigated. Methods : BEAS-2B and A549 cells, pulmonary alveolar macrophages, peripheral blood monocytes and lymphocytes were used. The cells were pre-treated with CsA, or FK506, for various time periods, followed by stimulation with TNF-${\alpha}$, LPS or IL-$1{\beta}$. The $I{\kappa}B{\alpha}$ expressions were assayed by Western blot analyses. The IKK activity was evaluated by an in vitro immune complex kinase assay, using GST-$I{\kappa}B{\alpha}$ as the substrate. Results : Neither CsA nor FK506 affected the level of $I{\kappa}B{\alpha}$ expression in any of the cell types used in this study. CsA pre-treatment inhibited the TNF ${\alpha}$-induced $I{\kappa}B{\alpha}$ degradation in bronchial epithelial cells. In contrast, the TNF ${\alpha}$-induced $I{\kappa}B{\alpha}$ degradation was not affected by FK506 pre-treatment. However, FK506 suppressed the cytokine-induced $I{\kappa}B{\alpha}$ degradation in the pulmonary alveolar macrophages, peripheral blood monocytes and lymphocytes. The inhibitory effect of CsA, or FK506, on $I{\kappa}B{\alpha}$ degradation was not related to IKK. Conclusions : CsA and FK506 suppressed the $I{\kappa}B{\alpha}$ degradation in bronchial epithelial cells, monocytes, lymphocytes and alveolar macrophages, so this may not be mediated through IKK.

• Tuberculosis and Respiratory Diseases
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• v.68 no.3
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• pp.168-174
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• 2010

Background: Sepsis still has a high mortality rate despite adequate supportive care. Newer therapeutic modalities have been developed but they have generally ended in failure. Recently, insulin was reported to have an anti-inflammatory effect by inhibiting the $I{\kappa}B/NF-{\kappa}B$ pathway, and may have therapeutic potential in sepsis. However, the precise mechanism of the anti-inflammatory effect of insulin is unclear. This study examined the role of insulin in activating $I{\kappa}B/NF-{\kappa}B$ in macrophage. Methods: Raw 264.7 cells, a murine macrophage cell line, were used in this experiment. Western blotting using $I{\kappa}B$ Ab and phosphor-specific $I{\kappa}B$ Ab was performed to evaluate the degradation and phosphorylation of $I{\kappa}B$ cells. For the $I{\kappa}B$ Kinase (IKK) activity, an immune complex kinase assay was performed. The level of interleukin-6 (IL-6) was measured by ELISA to determine the level of proinflammatory cytokine. Results: $I{\kappa}B{\alpha}$ degradation began 30 min after lipopolysaccharide (LPS) treatment. However, an insulin pretreatment suppressed the $I{\kappa}B{\alpha}$ degradation caused by the LPS treatment. The phosphorylation of $I{\kappa}B{\alpha}$ and IKK activity was also inhibited by the insulin pretreatment. Finally, the insulin pretreatment showed a tendency to suppress the induction of IL-6 by LPS. Conclusion: Insulin might have an anti-inflammatory effect though partial inhibition of the $I{\kappa}B/NF{\kappa}B$ pathway in macrophage cell lines.

• Tuberculosis and Respiratory Diseases
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• v.55 no.5
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• pp.488-498
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• 2003

Background : Activation of the transcription factor NF-${\kappa}B$ has been shown to protect cells from tumor necrosis factor-alpha, chemotherapy, and radiation-induced apoptosis. NF-${\kappa}B$-dependent cIAP expression is a major antiapoptotic mechanism for that. NF-${\kappa}B$ activation and cIAP expression in A549 lung cancer cells which is relatively resistant to radiation-induced cell death were investigated for the mechanism of radioresistance. Materials and methods : We used A549 lung cancer cells and Clinac 1800C linear accelerator for radiation. Cell viability test was done by MTT assay. NF-${\kappa}B$ activation was tested by luciferase reporter gene assay, Western blot for $I{\kappa}B{\alpha}$ degradation, and electromobility shift assay. For blocking ${\kappa}B$, MG132 and transfection of $I{\kappa}B{\alpha}$-superrepressor plasmid construct were used. cIAP expression was analyzed by RT-PCR and cIAP2 promoter activity was performed using luciferase assay system. Results : MTT assay showed that cytotoxicity even 48 hr after radiation in A549 cells were less than 20%. Luciferas assay demonstrated weak NF-${\kappa}B$ activation of $1.6{\pm}0.2$ fold compared to PMA-induced $3.4{\pm}0.9$ fold. Radiation-induced $I{\kappa}B{\alpha}$ degradation was observed in Western blot and NF-${\kappa}B$ DNA binding was confirmed by EMSA. However, blocking NF-${\kappa}B$ using MG132 and $I{\kappa}B{\alpha}$-superrepressor transfection did not show any sensitizing effect for radiation-induced cell death. The result of RT-PCR for cIAP1 & 2 expression was negative induction while TNF-${\alpha}$ showed strong expression for cIAP1 & 2. The cIAP2 promoter activity also did not show any change compared to positive control with TNF-${\alpha}$. Conclusion : We conclude that activation of NF-${\kappa}B$ does not determine the intrinsic radiosensitivity of cancer cells, at least for the cell lines tested in this study.

• Korean Journal of Microbiology
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• v.54 no.3
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• pp.208-213
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• 2018

Activation of nuclear factor kappa B ($NF{\kappa}B$) leads to the inflammatory process. During this $NF{\kappa}B$-dependent inflammation process, inducible nitric oxide synthase (iNOS) are expressed in the inflammatory cells. Our previous data indicated that a specific septapeptide (GVAWWMY) from the soybean extract fermented by Bacillus licheniformis B1 inhibited iNOS mRNA expression and NO production in cultured macrophage cells. Our further experiments revealed that treatment of same septapeptide resulted in inhibition of LPS-induced $NF{\kappa}B$ activation by reversing degradation of $I{\kappa}B{\alpha}$, an inhibitory protein for $NF{\kappa}B$. The molecular docking indicated that the septapeptide binds to $I{\kappa}B$ kinase ${\beta}$ ($IKK{\beta}$), and thus it can inhibit phosphorylation of $I{\kappa}B{\alpha}$. Supporting this, the binding site for the septapeptide has the highest affinity (-8.7 kcal/mol) and the site was located at the kinase domain (KD) of $IKK{\beta}$, which can significantly affect the kinase activity of $IKK{\beta}$.

• Tuberculosis and Respiratory Diseases
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• v.51 no.2
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• pp.122-134
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• 2001

Background : Some chemotherapeutic drugs induce NF-${\kappa}B$ activation by degrading the $I{\kappa}B{\alpha}$ protein in cancer cells which contributes to anticancer drug resistance. We hypothesized that inhibiting $I{\kappa}B{\alpha}$ degradation would block NF-${\kappa}B$ activation and result in increased tumor cell mortality in response to chemotherapy. Methods : The "superrepressor" form of the NF-${\kappa}B$ inhibitor was transferred by an adenoviral vector (Ad-$I{\kappa}B{\alpha}$-SR) to the human lung cancer cell lines (NCI H157 and NCI H460). With a MIT assay, the level of sensitization to cisplatin and paclitaxel were measured. To confirm the mechanism, an EMSA and Annexin V assay were performed. Results : EMSA showed that $I{\kappa}B{\alpha}$-SR effectively blocked the NF-${\kappa}B$ activation induced by cisplatin. Transduction with Ad-$I{\kappa}B{\alpha}$-SR resulted in an increased sensitivity of the lung cancer cell lines to cisplatin and paclitaxel by a factor of 2~3 in terms of $IC_{50}$. Annexin-V analysis suggests that this increment in chemosensitivity to cisplatin probably occurs through the induction of apoptosis. Conclusion : The blockade of chemotherapeutics induced NF-${\kappa}B$ activation by inducing Ad-$I{\kappa}B{\alpha}$-SR, increased apoptosis and increasing the chemosensitivity of the lung cancer cell lines tested, subsequently. Gene transfer of $I{\kappa}B{\alpha}$-SR appears to be a new therapeutic strategy of chemosensitization in lung cancer.

• Journal of Acupuncture Research
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• v.23 no.3
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• pp.91-102
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• 2006

목적 : 이 연구에서는 FBS에 의하여 유도되는 혈관 평활근 세포 증식에 대한 봉약침액과 Melittin의 세포 고사효과의 영향 및 작용 기전을 살펴보고자 하였다. 방법 : $I{\kappa}Ba$, p-$I{\kappa}Ba$, p-ERK1/2, p-Akt, p53, Bcl-2, Bax 및 active caspase-3는 Western blotting을, $NF-{\kappa}B$는 EMSA와 immunofluorescence staining을 이용하여 측정하였다. 결과 : 1. Melittin은 $NF-{\kappa}B$ 활성에 대하여 $I{\kappa}Ba$의 인산화를 유의하게 익제하고 $I{\kappa}Ba$를 증가시켰으며, $NF-{\kappa}B$의 DNA 결합과 $NF-{\kappa}B$ p50의 핵 내 유입을 유의하게 감소시켰다. 2. Melittin은 $NF-{\kappa}B$ 활성을 증가시키는 물질인 Akt의 인산화를 유의하게 억제하였고, ERK1/2의 인산화도 억제하였다. 3. Melittin은 세포사멸 전구 단백질인 p53, Bax 및 caspase-3의 발현을 유의하게 증가시켰고, 세포사멸억제 단백질인 Bcl-2의 발현은 감소시켰다. 결론 : 이상의 결과는 $NF-{\kappa}B$ 와 Akt 활성을 억제함으로써 혈관평활근세포 증식을 억제하는 효과가 있음을 입증한 것이며, 향후 안전성 연구를 바탕으로 혈관성형술 후 재발성협착증과 동맥경화증의 치료제로 사용될 수 있을 것으로 기대된다.

• Tuberculosis and Respiratory Diseases
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• v.54 no.5
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• pp.542-550
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• 2003

Background : Synthetic glucocorticoids are widely used in many chronic inflammatory diseases because of their excellent anti-inflammatory activity. Enhancing the transcription of $I{\kappa}B$ and preventing activated NF-${\kappa}B$ from binding to ${\kappa}B$ sites are thought to be the underlying mechanisms. But these data are largely derived from in vitro studies using cell lines. In this study, after administrating a steroid to volunteers, we evaluated the effect on the NF-${\kappa}B$ system. Methods : Prednisolone(0.5mg/kg/d) was orally administered to 5 healthy volunteers for 7 days. Before and after the administration, we sampled their peripheral blood monocytes, and performed western blot analysis both with stimulation, using IL-$1{\beta}$, LPS, TNF, and without stimulation(baseline). We also performed EMSA after stimulation with LPS. Results : After ingestion of the steroid, baseline expressions of $I{\kappa}B{\alpha}$ were increased in two of the subjects, while suppressed degradations of $I{\kappa}B{\alpha}$ to stimulations were observed in all five. In addition, the binding capacity of NF-${\kappa}B$ after the administration was decreased. Conclusion : Steroid plays such roles as enhancing the transcription of $I{\kappa}B{\alpha}$, suppressing the DNA binding capacity of NF-${\kappa}B$, and suppressing the degradation of $I{\kappa}B{\alpha}$.

• Journal of Nutrition and Health
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• v.50 no.1
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• pp.25-31
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• 2017

Purpose: Neuroinflammation is mediated by activation of microglia implicated in the pathogenesis of neurodegenerative disorders such as Alzheimer's disease and Parkinson's disease. Inhibition of neuroinflammation may be an effective solution to treat these brain disorders. Petalonia binghamiae is known as a traditional food, based on multiple biological activities such as anti-oxidant and anti-obesity. In present study, the anti-neuroinflammatory potential of Petalonia binghamiae was investigated in LPS-stimulated BV2 microglial cells. Methods: Cell viability was measured by MTT assay. Production of nitric oxide (NO) was examined using Griess reagent. Expression of inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2) was detected by Western blot analysis. Activation of nuclear factor ${\kappa}B$ ($NF-{\kappa}B$) signaling was examined by nuclear translocation of $NF-{\kappa}B$ p65 subunit and phosphorylation of $I{\kappa}B$. Results: Extract of Petalonia binghamiae significantly inhibited LPS-stimulated NO production and iNOS/COX-2 protein expression in a dose-dependent manner without cytotoxicity. Pretreatment with Petalonia binghamiae suppressed LPS-induced $NF-{\kappa}B$ p65 nuclear translocation and phosphorylation of $I{\kappa}B$. Co-treatment with Petalonia binghamiae and pyrrolidine duthiocarbamate (PDTC), an $NF-{\kappa}B$ inhibitor, reduced LPS-stimulated NO release compared to that in PB-treated or PDTC-treated cells. Conclusion: The present results indicate that extract of Petalonia binghamiae exerts anti-neuroinflammation activities, partly through inhibition of $NF-{\kappa}B$ signaling. These findings suggest that Petalonia binghamiae might have therapeutic potential in relation to neuroinflammation and neurodegenerative diseases.

• Molecules and Cells
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• v.41 no.8
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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.