• 한국식품과학회지
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• 제40권3호
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• pp.332-336
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• 2008

선천성 면역은 병원성균의 침입에 대항하기 위한 숙주의 최초 방어체계라 할 수 있다. 이러한 선천성 면역반응은 병원균들이 가지고 있는 독특한 구조를 인식하는 TLRs에 의해서 조절되어 진다고 알려져 있다. 숙주에 침입한 여러 병원성균들이 TLRs를 자극하며 이렇게 자극된 신호들은 아래로 전달되어 전사요소 $NF-{\kappa}B$의 활성화를 유도하고 결국 COX-2와 같은 염증 유발인자를 유도하여 암이나 질병을 유발하게 된다. 우리는 이번 연구를 통하여 생강 추출물중의 하나인 6-shogaol이 어떻게 $NF-{\kappa}B$ 활성화나 COX-2 발현을 조절하여 항염증 효과를 가지고 있는지를 알아보았다. 6-shogaol은 TLR2, TLR3, TLR4 agonists에 의해서 유도된 $NF-{\kappa}B$ 활성화와 COX-2 발현을 억제하였다. 이러한 결과는6-shogaol이 여러 병원균들로부터 유도되는 염증반응이나 만성적인 질병들을 조절할 수 있다는 중요한 결과를 보여주는 것이라 할 수 있다.

• Journal of Microbiology and Biotechnology
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• 제29권8호
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• pp.1316-1323
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• 2019

Middle East respiratory syndrome coronavirus (MERS-CoV) is a newly emerging coronavirus which is zoonotic from bats and camels. Its infection in humans can be fatal especially in patients with preexisting conditions due to smoking and chronic obstructive pulmonary disease (COPD). Among the 25 proteins encoded by MERS-CoV, 5 accessory proteins seem to be involved in viral evasion of the host immune responses. Here we report that ORF4a, ORF4b, and ORF8b proteins, alone or in combination, effectively antagonize nuclear factor kappa B ($NF-{\kappa}B$) activation. Interestingly, the inhibition of $NF-{\kappa}B$ by MERS-CoV accessory proteins was mostly at the level of pattern recognition receptors: melanoma differentiation-associated gene 5 (MDA5). ORF4a and ORF4b additively inhibit MDA5-mediated activation of $NF-{\kappa}B$ while that of retinoic acid-inducible gene 1 (RIG-I) is largely not perturbed. Of note, ORF8b was found to be a novel antagonist of MDA5-mediated $NF-{\kappa}B$ activation. In addition, ORF8b also strongly inhibits Tank-binding kinase 1 (TBK1)-mediated induction of $NF-{\kappa}B$ signaling. Taken together, MERS-CoV accessory proteins are involved in viral escape of $NF-{\kappa}B$-mediated antiviral immune responses.

• Biomolecules & Therapeutics
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• 제29권3호
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• pp.303-310
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• 2021

In the present study, kaempferol, a flavonoidal natural compound found in Polygonati Rhizoma, was investigated for its potential effect on the gene expression and production of airway MUC5AC mucin. A human respiratory epithelial NCI-H292 cells was pretreated with kaempferol for 30 min and stimulated with epidermal growth factor (EGF) or phorbol 12-myristate 13-acetate (PMA), for the following 24 h. The effect on PMA-induced nuclear factor kappa B (NF-κB) signaling pathway or EGF-induced mitogen-activated protein kinase (MAPK) signaling pathway was investigated. Kaempferol suppressed the production and gene expression of MUC5AC mucins, induced by PMA through the inhibition of degradation of inhibitory kappa Bα (IκBα), and NF-κB p65 nuclear translocation. Also, kaempferol inhibited EGF-induced gene expression and production of MUC5AC mucin through regulating the phosphorylation of EGFR, phosphorylation of p38 MAPK and extracellular signal-regulated kinase (ERK) 1/2 (p44/42), and the nuclear expression of specificity protein-1 (Sp1). These results suggest kaempferol regulates the gene expression and production of mucin through regulation of NF-κB and MAPK signaling pathways, in human airway epithelial cells.

• 대한의생명과학회지
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• 제20권1호
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• pp.32-38
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• 2014

Potassium cyanate (KOCN) that is known as an inducer of the protein carbamylation is an inorganic compound and is the conjugate based of cyanic acid (HOCN). Based on these studies, we confirmed that KOCN induces the apoptosis of the human colorectal cancer cell line, HCT 116 cells, by various mitochondrial pathways. To investigate other mechanisms of KOCN-mediated apoptosis, in the present study, we examined KOCN-induced cytokines production in HCT 116 cells and identified the intracellular signaling pathway in these processes. We first demonstrated that KOCN considerably increased the cell apoptosis via intracellular $Ca^{2+}$ signaling, mitochondrial dysfunction and ROS production. And then we examined TNF-${\alpha}$ and IL-$1{\beta}$ levels mediated by KOCN in HCT 116 cells. Although IL-$1{\beta}$ was not involved in KOCN-mediated HCT 116 cell apoptosis, the release of TNF-${\alpha}$ was mediated by KOCN in HCT 116 cells via NF-${\kappa}B$ activation. Apoptosis was also enhanced by incubation with supernatants from HCT 116 cells after KOCN treatment and this effect was partially reduced by BAY 11-7085 pre-treated supernatant. Taken together, our results indicate that KOCN-induced apoptosis in HCT 116 cells is dependent on the releases of TNF-${\alpha}$ and the increased factors and that the mechanism involves the activation of NF-${\kappa}B$.

• 대한화장품학회지
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• 제32권3호
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• pp.135-140
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• 2006

Nucler factor-kappa B (NF-kappaB) 프로모터는 염증성 질환을 유도하는 호염증성 시토카인의 발현에 중요한 역할을 수행하는 전사인자 중의 하나이다. 본 실험에서는 200 여종의 식물추출물들로부터 항염효능이 있는 추출물을 선발하기 위해 NF-kappaB 리포터 실험을 수행하였다. NF-kappaB 리포터 실험결과, 12종의 식물추출물, 즉 개나리, 고추잎, 박하, 뱀딸기, 뽕나무, 삼백초, 솔잎, 양애줄기, 약쑥, 어성초, 왕벚꽃가지, 조릿대 등이 lipopolysaccharide (LPS)에 의해 유도된 NF-kappaB 프로모터 활성을 농도의존적으로 억제하는 것을 확인하였다. 이들 12종의 식물추출물이 호염증성 시토카인 발현에도 동일한 효과를 나타내는지 알아보기 위해 tumor necrosis factor-alpha (TNF alpha)와 인터루킨-8에 대한 ELISA실험을 실시하였다. ELISA실험 결과, NF-kappaB 리포터 실험결과와 동일하게, TNF-alpha와 인터루킨-8 생산이 12종 식물추출물 모두에서 감소됨을 관찰하였다. 이러한 실험결과는, 12종의 식물 추출물에서 보여지는 호염증성 시토카인 억제효과가 NF-kappaB 프로모터 활성억제를 통해 이루어지고 있음을 시사한다. 또한, 이들 12종 식물은 diphenyl-p-picrylhydrazyl (DPPH) assay를 통해 살펴본 결과 높은 항산화 활성도 있음을 확인하였다. 이상의 결과로부터, 12종의 식물 추출물은 염증성 피부질환 전용 화장품 제형에서 항염 및 자극완화 소재로 응용될 수 있음을 확인하였다.

• Molecules and Cells
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• 제40권10호
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• pp.706-713
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• 2017

Osteoclasts are bone-resorbing cells that are derived from hematopoietic precursor cells and require macrophage-colony stimulating factor and receptor activator of nuclear factor-${\kappa}B$ ligand (RANKL) for their survival, proliferation, differentiation, and activation. The binding of RANKL to its receptor RANK triggers osteoclast precursors to differentiate into osteoclasts. This process depends on RANKL-RANK signaling, which is temporally regulated by various adaptor proteins and kinases. Here we summarize the current understanding of the mechanisms that regulate RANK signaling during osteoclastogenesis. In the early stage, RANK signaling is mediated by recruiting adaptor molecules such as tumor necrosis factor receptorassociated factor 6 (TRAF6), which leads to the activation of mitogen-activated protein kinases (MAPKs), and the transcription factors nuclear factor-${\kappa}B$ (NF-${\kappa}B$) and activator protein-1 (AP-1). Activated NF-${\kappa}B$ induces the nuclear factor of activated T-cells cytoplasmic 1 (NFATc1), which is the key osteoclastogenesis regulator. In the intermediate stage of signaling, the co-stimulatory signal induces $Ca^{2+}$ oscillation via activated phospholipase $C{\gamma}2$ ($PLC{\gamma}2$) together with c-Fos/AP-1, wherein $Ca^{2+}$ signaling facilitates the robust production of NFATc1. In the late stage of osteoclastogenesis, NFATc1 translocates into the nucleus where it induces numerous osteoclast-specific target genes that are responsible for cell fusion and function.

• Molecules and Cells
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• 제43권1호
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• pp.23-33
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• 2020

NF-κB signaling through both canonical and non-canonical pathways plays a central role in immune responses and inflammation. NF-κB-inducing kinase (NIK) stabilization is a key step in activation of the non-canonical pathway and its dysregulation implicated in various hematologic malignancies. The tumor suppressor, p53, is an established cellular gatekeeper of proliferation. Abnormalities of the TP53 gene have been detected in more than half of all human cancers. While the non-canonical NF-κB and p53 pathways have been explored for several decades, no studies to date have documented potential cross-talk between these two cancer-related mechanisms. Here, we demonstrate that p53 negatively regulates NIK in an miRNA-dependent manner. Overexpression of p53 decreased the levels of NIK, leading to inhibition of the non-canonical NF-κB pathway. Conversely, its knockdown led to increased levels of NIK, IKKα phosphorylation, and p100 processing. Additionally, miR-34b induced by nutlin-3 directly targeted the coding sequences (CDS) of NIK. Treatment with anti-miR-34b-5p augmented NIK levels and subsequent non-canonical NF-κB signaling. Our collective findings support a novel cross-talk mechanism between non-canonical NF-κB and p53.

• BMB Reports
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• 제47권9호
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• pp.524-529
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• 2014

Oxidative stress and inflammation are common to many pathological conditions. Defense mechanisms protect cells from oxidative stress, but can become over-activated following injury and inflammation. NF-${\kappa}B$ and Nrf2 transcription factors regulate proinflammatory and antioxidant gene expression, respectively. Studies have shown that many natural dietary compounds regulate NF-${\kappa}B$ and Nrf2, preventing inflammation and oxidative stress. Here, we report major compounds of Prunella vulgaris var. lilacina such as rosmarinic acid, oleanolic acid, ursolic acid and caffeic acid as a potential therapeutic for oxidative stress and inflammation. The major compounds exhibited high anti-inflammatory activity, inhibiting NO, PGE2 production, NF-${\kappa}B$ expression and activating Nrf2 expression. In addition, we examined the effect of major compounds on MafK expression. Among the compounds, oleanolic acid significantly decreased MafK expression and MafK-mediated p65 acetylation. These findings suggest that oleanolic acid as NF-${\kappa}B$ inhibitors can potentially be used in therapeutic applications for the treatment of oxidative stress-induced diseases.

• Molecules and Cells
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• 제26권1호
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• pp.48-52
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• 2008

We here demonstrate an anti-inflammatory action of raloxifene, a selective estrogen receptor modulator, in lipopolysaccharide (LPS)-induced murine macrophage RAW264.7 cells. Treatment with raloxifene at micromolar concentrations suppressed the production of nitric oxide (NO) by down-regulating expression of the inducible nitric oxide synthase (iNOS) gene in LPS-activated cells. The decreased expression of iNOS and subsequent reduction of NO were due to inhibition of nuclear translocation of transcription factor NF-${\kappa}B$. These effects were significantly inhibited by exposure to the phosphatidylinositol 3-kinase (PI 3-kinase) inhibitor, LY294002, or by expression of a dominant negative mutant of PI 3-kinase. In addition, pretreatment with raloxifene reduced LPS-induced Akt phosphorylation as well as NF-${\kappa}B$ DNA binding activity and NF-${\kappa}B$-dependent reporter gene activity. Thus our findings indicate that raloxifene exerts its anti-inflammatory action in LPS-stimulated macrophages by blocking the PI 3-kinase-Akt-NF-${\kappa}B$ signaling cascade, and eventually reduces expression of pro-inflammatory genes such as iNOS.

• Asian Pacific Journal of Cancer Prevention
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• 제14권7호
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• pp.4441-4446
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• 2013

Cholangiocarcinoma (CCA) is a tumor of biliary ducts, which has a high mortality rate and dismal prognosis. Constitutively activation of the transcription factor nuclear factor kappa-B (NF-${\kappa}B$) has been previously demonstrated in CCA. It is therefore a potential target for CCA treatment. Effects of diethyldithiocarbamate (DDTC) on NF-${\kappa}B$-dependent apoptosis induction in cancer have been reported; however, anti-metastasis has never been addressed. Therefore, here the focus was on DDTC effects on CCA migration and adhesiond. Anti-proliferation, anti-migration and anti-adhesion activities were determined in CCA cell lines, along with p65 protein levels and function. NF-${\kappa}B$ target gene expression was determined by quantitative RT-PCR. DDTC inhibited CCA cell proliferation. Suppression of migration and adhesion were observed prior to anti-CCA proliferation. These effects were related to decreased p65, reduction in NF-${\kappa}B$ DNA binding, and impaired activity. Moreover, suppression of ICAM-1 expression supported NF-${\kappa}B$-dependent anti-metastatic effects of DDTC. Taken together, DDTC suppression of CCA migration and adhesion through inhibition of NF-${\kappa}B$ signaling pathway is suggested from the current study. This might be a promising treatment choice against CCA metastasis.