• The Korean Journal of Physiology and Pharmacology
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• 제7권2호
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• pp.65-71
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• 2003

Increasing evidences suggest that ischemia-induced vascular damage is an integral step in the cascade of the cellular and molecular events initiated by cerebral ischemia. In the present study, employing a mouse brain endothelioma-derived cell line, bEnd.3, and oxygen-glucose deprivation (OGD) as an in vitro stroke model, the role of nuclear factor kappa B (NF-${\kappa}B$) activation during ischemic injury was investigated. OGD was found to activate NF-${\kappa}B$ and to induce bEnd.3 cell death in a time-dependent manner. OGD phosphorylated neither 32 Ser nor 42 Tyr of $I{\kappa}B{\alpha}$. OGD did not change the amount of $I{\kappa}B{\alpha}$. The extents of OGD-induced cell death after 8 h, 10 h, 12 h and 14 h of OGD were 10%, 35%, 60% and 85%, respectively. Reperfusion following OGD did not cause additional cell death, indicating no reperfusion injury after ischemic insult in cerebral endothelial cells. Three known as NF-${\kappa}B$ inhibitors, including pyrrolidine dithiocarbamate (PDTC) plus zinc, aspirin and caffeic acid phenethyl ester (CAPE), inhibited OGD-induced NF-${\kappa}B$ activation and increased OGD-induced bEnd.3 cell death in a dose dependent manner. There were no changes in the protein levels of bcl-2, bax and p53 which are modulated by NF-${\kappa}B$ activity. These results suggest that NF-${\kappa}B$ activation might be a protective mechanism for OGD-induced cell death in bEnd.3.

• Food Science and Biotechnology
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• 제15권2호
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• pp.303-307
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• 2006

Effect of Oenanthe javanica ethanol extract (OJE) on nuclear factor-${\kappa}B$ (NF-${\kappa}B$)-mediated inflammatory reaction in RAW 264.7 macrophage cells was investigated. The OJE dose-dependently inhibited secretions of tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) and prostaglandins $E_2\;(PGE_2)$ from lipopolysaccharide (LPS)-stimulated RAW 264.7 cells and blocked LPS-induced expression of cyclooxygenase-2. To clarify mechanistic basis for its inhibitions of NF-${\kappa}B$ and activator protein-1 (AP-1) activations, effects of OJE on activations of NF-${\kappa}B$ and AP-1 genes by luciferase reporter activity were examined. The LPS-stimulated activations of NF-${\kappa}B$ and AP-1 were significantly blocked by 400 and $600\;{\mu$}g/mL of OJE, implicating that OJE might regulate gene expression through more than one signaling pathway. Cytosolic degradation of I-${\kappa}B{\alpha}$ was inhibited by OJE dose-dependently, indicating that the nuclear translocation of p65 was inhibited by OJE. These findings suggest that the inhibition of LPS-stimulated COX-2 expression by OJE is due to its inhibition of NF-${\kappa}B$ activation by blocking I-${\kappa}B{\alpha}$ degradation, which may be mechanistic basis of anti-inflammatory effects of OJE.

• 동의생리병리학회지
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• 제21권4호
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• pp.1017-1024
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• 2007

Thymus and activation-regulated chemokine (TARC/CCL-17), produced by keratinocytes, is a CC chemokine known to selectively Th2 type T cells via $CCR4^+$ and is implicated in the development of atopic dermatitis (AD). TARC/CCL17 expression was induced by cytokines such as tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) and interferon-${\gamma}$ (IFN-${\gamma}$). We recently found that the wogonin, a flavone isolated from Scutellaria baicalensis, suppressed TARC expression via heme oxygenase 1 (HO1) in human keratinocytes induced with mite antigen. However, little is known about the inhibitory mechanism of wogonin on TARC/CCL-17 expression stimulated with cytokines. To investigate the inhibitory mechanism, I determined the inhibitory effects of wogonin on the activation of nuclear factor-${\kappa}B$ (NF-${\kappa}B$) and $I{\kappa}B{\alpha}$ phosphorylation, and also examined the activation of p38 MAP kainase in HaCaT keratinocytes stimulated with TNF-${\alpha}$ and IFN-${\gamma}$. Wogonin inhibited NF-${\kappa}B$-DNA complex, NF-${\kappa}B$ binding activity, and the phosphorylation of $I{\kappa}B{\alpha}$ in a dose dependent manner. Wogonin also inhibited the translocation of NF-${\kappa}B$ from cytosol to nucleus. Moreover, the phosphorylation of of p38 MAP kinase in the TNF-${\alpha}$ and IFN-${\gamma}$-stimulated HaCaT keratinocytes were suppressed by wogonin in a dose dependent manner. These results suggest that wogonin may inhibit cytokine-induced NF-${\kappa}B$ activation by $I{\kappa}B{\alpha}$ degradation via suppression of p38 MAP kinase signaling pathway in keratinocytes and modulation of wogonin signaling pathway may be beneficial for the treatment of AD.

• 셀메드
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• 제2권3호
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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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• 제41권12호
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• pp.1008-1015
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• 2018

$I{\kappa}B$, a cytoplasmic inhibitor of nuclear factor-${\kappa}B$ ($NF-{\kappa}B$), is reportedly degraded via the proteasome. However, we recently found that long-term incubation with proteasome inhibitors (PIs) such as PS-341 or MG132 induces $I{\kappa}B{\alpha}$ degradation via an alternative pathway, lysosome, which results in $NF-{\kappa}B$ activation and confers resistance to PI-induced lung cancer cell death. To enhance the anti-cancer efficacy of PIs, elucidation of the regulatory mechanism of PI-induced $I{\kappa}B{\alpha}$ degradation is necessary. Here, we demonstrated that PI up-regulates nuclear factor (erythroid-derived 2)-like 2 (Nrf2) via both de novo protein synthesis and Kelch-like ECH-associated protein 1 (KEAP1) degradation, which is responsible for $I{\kappa}B{\alpha}$ degradation via macroautophagy activation. PIs increased the protein level of light chain 3B (LC3B, macroautophagy marker), but not lysosome-associated membrane protein 2a (Lamp2a, the receptor for chaperone-mediated autophagy) in NCI-H157 and A549 lung cancer cells. Pretreatment with macroautophagy inhibitor or knock-down of LC3B blocked PI-induced $I{\kappa}B{\alpha}$ degradation. PIs up-regulated Nrf2 by increasing its transcription and mediating degradation of KEAP1 (cytoplasmic inhibitor of Nrf2). Overexpression of dominant-negative Nrf2, which lacks an N-terminal transactivating domain, or knock-down of Nrf2 suppressed PI-induced LC3B protein expression and subsequent $I{\kappa}B{\alpha}$ degradation. Thus, blocking of the Nrf2 pathway enhanced PI-induced cell death. These findings suggest that Nrf2-driven induction of LC3B plays an essential role in PI-induced activation of the $I{\kappa}B$/$NF-{\kappa}B$ pathway, which attenuates the anti-tumor efficacy of PIs.

• 생명과학회지
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• 제23권4호
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• pp.471-478
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• 2013

인체 중간엽 줄기세포는 다양한 세포로의 분화 및 자가증식 할 수 있는 능력뿐만 아니라 질병치료에 대한 치료적 잠재력을 가지고 있다. 줄기세포 분화의 분자 기작에 대한 이해는 줄기세포 이식의 치료 효능을 향상시킨다. 본 연구에는 인체 중간엽 줄기세포의 골분화에서 NFAT5의 역할을 밝혔다. 특이적 siRNA의 transfection으로 인한 NFAT5의 억제는 인체 중간엽 줄기세포의 골분화를 현저히 감소시켰으며, NF-${\kappa}B$ promoter 활성화 또한 세포의 증식이나 지방 세포로의 분화에 영향 없이 감소 시켰다. NFAT5의 발현 억제는 기본적으로 유도되는 NF-${\kappa}B$의 활성화와 TNF-${\alpha}$에 의해서 유도되는 NF-${\kappa}B$의 활성화를 감소시켰으나, TNF-${\alpha}$에 의해서 유도되는 NF-${\kappa}B$의 분해에는 아무런 영향을 주지 않았다. 이번 연구를 통해 NFAT5가 NF-${\kappa}B$ 경로를 조절함으로써 인체 중간엽 줄기 세포의 골분화에 아주 중요한 역할을 하는 것을 확인 할 수 있었다.

• 한국식생활문화학회지
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• 제33권4호
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• pp.337-344
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• 2018

Germinated brown rice (GBR, Orysa sartiva L.) has been reported to have anti-obesity and anti-inflammatory effects. However, the mechanisms underlying these effects in adipocytes are not fully understood. Therefore, this study was conducted to explore the anti-inflammatory mechanisms of GBR on lipopolysaccharide (LPS)-stimulated 3T3-L1 adipocytes. 3T3-L1 adipocytes were pretreated with GBR extracts (0-20 mg/mL) 1 h before LPS stimulation. The mRNA expression of adipokines and Toll-like receptor 4 (TLR4) were measured by RT-PCR. The protein expressions of TLR4-related molecules were detected by western blotting and nuclear factor-${\kappa}B$ ($NF-{\kappa}B$) activation was measured. Our results showed that GBR extract dose-dependently inhibited mRNA expression of LPS-induced tumor necrosis factor-${\alpha}$ ($TNF-{\alpha}$), interleukin-6 (IL-6), and monocyte chemoattractant protein-1 (MCP-1). GBR extract was found to inhibit LPS-induced mRNA expression of TLR4 and protein expression of both myeloid differentiation factor 88 (MyD88) and TNF receptor-associated factor 6 (TRAF6). Furthermore, GBR extract significantly inhibited extracellular receptor-activated kinase (ERK) phosphorylation and $NF-{\kappa}B$ activation. These results suggest that GBR extract has the anti-inflammatory effects on LPS-induced inflammation via inhibition of TLR4 signaling, includingthe ERK and $NF-{\kappa}B$ signaling pathways, in adipocytes.

• 생명과학회지
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• 제20권12호
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• pp.1772-1776
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• 2010

내재면역반응의 중요한 조절자인 Nrf2와 NF-${\kappa}B$는 염증시에 교차 작용을 통하여 서로의 전사활성을 조절할 수 있다고 보고된 바 있으나 상반된 결과도 제시되고 있어서 아직까지 확실하게 규명되어 있지 않다. 저자들은 선행연구에서 NF-${\kappa}B$ 저해제인 금(I)-화합물 오라노핀이 인간 관절활막세포와 단핵구성 세포에서 Nrf2를 활성화시킴을 확인한 바 있기 때문에, 본 연구에서는 Nrf2를 knockdown 시킨 류마티스성 활막세포를 사용하여 오라노핀에 의해 저해되는 NF-${\kappa}B$ 신호전달 과정에 Nrf2가 관여하는지를 조사하였다. 세포를 Nrf2 siRNA로 transfection시켰을 때 Nrf2 발현은 대부분 차단됨을 확인하였다. 하지만 Nrf2 knockdown은 TNF-$\alpha$에 의해 유도되는 $I{\kappa}B-{\alpha}$ 분해를 막는 오라노핀의 작용에는 영향을 주지 않았다. Nrf2 target 단백질로서 항염 작용에 관여하는 HO-1을 knockdown 시켰을 경우에도 $I{\kappa}B-{\alpha}$ 분해를 저해하는 오라노핀의 작용에 영향을 미치지 않았다. 또한, Nrf2 knockdown은 오라노핀에 의해 저해된 ICAM-1 발현을 다시 복원시키지 못했다. 이러한 결과들은 염증성 싸이토킨에 의해 유도되는 NF-${\kappa}B$ 활성화를 오라노핀이 저해하는 기전에 Nrf2 및 HO-1이 관련되어 있지 않음을 시사한다. 따라서 류마티스성 관절활막세포에서 오라노핀의 항염작용 기전으로 알려진 Nrf2/HO-1 활성유도와 NF-${\kappa}B$ 활성저해는 교차작용 없이 각각 독립적인 기전을 통해 나타나는 것으로 생각된다.

• 동의생리병리학회지
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• 제22권6호
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• pp.1572-1578
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• 2008

In previous report, Seungmagalgeun-tang (SGT) could exert its anti-inflammatory actions in the BV-2 microglial cells. However, study on the anti-inflammatory effect of SGT in mast cells has not been identified. Therefore, we examined on the anti-inflammatory effect of SGT on the phorbol 12-myristate 13-acetate (PMA) and calcium ionophore A23187-induced rat basophilic leukemia (RBL-2H3) cells. SGT inhibited the release of ${\beta}$-hexosaminidase and secretion and expression of pro-inflammatory cytokines such as tumor necrosis factor (TNF)-${\alpha}$ and interleukin (IL)-4 on RBL-2H3 cells, without affecting cell viability. The protein expression level of nuclear factor (NF)-${\kappa}B$ (p65) was decreased in the nucleus by SGT. In addition, SGT suppressed the degradation of inhibitory protein $I{\kappa}B-{\alpha}$ protein, the activation of p38 mitogen-activated protein kinase (MAPK), and the expressions of cyclooxygenase (COX)-2 mRNA and protein level in RBL-2H3 cells. These results suggest that SGT could be involved anti-allergic effect by control of NF-${\kappa}B$ (p65) translocation into the nucleus through inhibition of $I{\kappa}B-{\alpha}$ degradation and suppression of COX-2 expression.

• Biomolecules & Therapeutics
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• 제21권6호
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• pp.435-441
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• 2013

Emodin, a naturally occurring anthraquinone derivative isolated from Polygoni cuspidati radix, has several beneficial pharmacologic effects, which include anti-cancer, anti-diabetic, and anti-inflammatory activities. In this study, the authors examined the effect of emodin on the production of proinflammatory cytokines, such as, tumor necrosis factor (TNF)-${\alpha}$ and interleukin (IL)-6, in mouse bone marrow-derived mast cells (BMMCs) stimulated with phorbol 12-myristate 13-acetate (PMA) plus the calcium ionophore A23187. To investigate the mechanism responsible for the regulation of pro-inflammatory cytokine production by emodin, the authors assessed its effects on the activations of transcriptional factor nuclear factor-${\kappa}B$ (NF-${\kappa}B$) and mitogen-activated protein kinases (MAPKs). Emodin attenuated the nuclear translocation of (NF)-${\kappa}B$ p65 and its DNA-binding activity by reducing the phosphorylation and degradation of $I{\kappa}B{\alpha}$ and the phosphorylation of $I{\kappa}B$ kinase B (IKK). Furthermore, emodin dose-dependently attenuated the phosphorylations of MAPKs, such as, extracellular signal-regulated kinase 1/2 (ERK1/2), p38 MAP kinase, and the stress-activated protein kinases (SAPK)/c-Jun-N-terminal kinase (JNK). Taken together, the findings of this study suggest that the anti-inflammatory effects of emodin on PMA plus A23187-stimulated BMMCs are mediated via the inhibition of NF-${\kappa}B$ activation and of the MAPK pathway.