• Title/Summary/Keyword: ${\kappa}B{\alpha}$

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The Shigella Flexneri Effector OspG Interferes with Innate Immune Responses by Targeting Ubiquitin-Conjugating Enzymes

  • Kim, Dong-Wook
    • Proceedings of the PSK Conference
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    • 2005.11a
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    • pp.231-232
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    • 2005
  • Bacteria of Shigella spp. are responsible for shigellosis in humans, a disease characterized by destruction of the colonic epithelium that is induced by the inflammatory response elicited by invasive bacteria. They use a type III secretion system injecting effector proteins into host cells to induce their entry into epithelial cells and triggers apoptosis in macrophages. We present evidence that the effector OspG is a protein kinase that binds various ubiquitinylated ubiquitin-conjugating enzymes (E2s) and blocks degradation of phospho-$I{\kappa}B{\alpha}$ induced upon entry of bacteria into epithelial cells. Transfection experiments confirmed that OspG interferes with the $NF-{\kappa}B$ activation patway by preventing phospho-$I{\kappa}B{\alpha}$ degradation, suggesting that OspG inactivates a component of the $SCF^{{\beta}-TrCP}$ ubiquitin ligase complex (E3) involved in phospho-$I{\kappa}B{\alpha}$ ubiquitination. Upon infection of ileal loops in rabbits, the ospG mutant induced a stronger inflammatory response compared with the wild-type strain, indicating that OspG down-regulates the host innate response induced by invasive bacteria.

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Inhibition of $NF-{\kappa}B$ Activation Increases Oxygen-Glucose Deprivation-Induced Cerebral Endothelial Cell Death

  • Lee, Jin-U;Kim, Chul-Hoon;Shim, Kyu-Dae;Ahn, Young-Soo
    • The Korean Journal of Physiology and Pharmacology
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    • v.7 no.2
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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.

Viridicatol from Marine-derived Fungal Strain Penicillium sp. SF-5295 Exerts Anti-inflammatory Effects through Inhibiting NF-κB Signaling Pathway on Lipopolysaccharide-induced RAW264.7 and BV2 Cells

  • Ko, Wonmin;Sohn, Jae Hak;Kim, Youn-Chul;Oh, Hyuncheol
    • Natural Product Sciences
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    • v.21 no.4
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    • pp.240-247
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    • 2015
  • Viridicatol (1) has previously been isolated from the extract of the marine-derived fungus Penicillium sp. SF-5295. In the course of further biological evaluation of this quinolone alkaloid, anti-inflammatory effect of 1 in RAW264.7 and BV2 cells stimulated with lipopolysaccharide (LPS) was observed. In this study, our data indicated that 1 suppressed the expression of well-known pro-inflammatory mediators such as inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2, and consequently inhibited the production of iNOS-derived nitric oxide (NO) and COX-2-derived prostaglandin E2 ($PGE_2$) in LPS stimulated RAW264.7 and BV2 cells. Compound 1 also reduced mRNA expression of pro-inflammatory cytokines such as $interleukin-1{\beta}$ ($IL-1{\beta}$), interleukin-6 (IL-6), and tumor necrosis $factor-{\alpha}$ ($TNF-{\alpha}$). In the further evaluation of the mechanisms of these anti-inflammatory effects, 1 was shown to inhibit nuclear factor-kappa B ($NF-{\kappa}B$) pathway in LPS-stimulated RAW264.7 and BV2 cells. Compound 1 blocked the phosphorylation and degradation of inhibitor kappa B $(I{\kappa}B)-{\alpha}$ in the cytoplasm, and suppressed the translocation of $NF-{\kappa}B$ p65 and p50 heterodimer in nucleus. In addition, viridicatol (1) attenuated the DNA-binding activity of $NF-{\kappa}B$ in LPS-stimulated RAW264.7 and BV2 cells.

Anti-Inflammatory Effects of Haliotidis Concha (석결명(石決明)의 항염증효과(抗炎症效果))

  • Moon, Soo-Young;Kim, Young-Woo;Kim, Sang-Chan
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.26 no.4
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    • pp.70-80
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    • 2013
  • Objectives : Haliotidis Concha has been used to treat various human diseases such as liver dysfunction and inflammatory disorder. Although it has been shown the effects of Haliotidis Concha on the various diseases, it has almost not been studied about the anti-inflammatory effects of the Haliotidis Concha and its mechanisms. Methods : This research investigated the effects of the Haliotidis Concha ethanol extract (HCE) on the production of nitric oxide (NO) and prostaglandin $E_2$ ($PGE_2$) as well as tumor necrosis factor-alpha (TNF-${\alpha}$). The protein expressions of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) were assayed by immunoblot analyses, and the productions of NO, $PGE_2$ and TNF-${\alpha}$ were assessed by ELISA. Results : Haliotidis Concha decreased the production of NO and $PGE_2$, and inhibited the expression iNOS and COX-2 proteins in a concentration-dependent manner in LPS-treated Raw 264.7 cells. HCE suppressed the ability of LPS to activate the signaling pathways of nuclear factor kappa B (NF-${\kappa}B$) as indicated by HCE inhibited nuclear NF-${\kappa}B$ level and I-${\kappa}B{\alpha}$ phosphorylation. Also, HCE inhibited mitogen-activated protein kinases (MAPKs). Conclusions : HCE repressed the production of LPS-inducible NO, $PGE_2$ and TNF-${\alpha}$, which may be mediated by inhibition of NF-${\kappa}B$ translocation. This study suggest the use for the treatment of acute inflammatory disorders.

Anti-inflammatory Effect of Fructus Chaenomelis(FC) (목과(木瓜)의 항염(抗炎) 및 면역반응(免疫反應)에 대한 실험적(實驗的) 연구(硏究))

  • Lee, Su-Jeong;Kim, Song-Baeg;Choe, Chang-Min;Lee, Key-Sang;Cho, Han-Baek
    • The Journal of Korean Obstetrics and Gynecology
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    • v.21 no.4
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    • pp.36-48
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    • 2008
  • Purpose: The purpose of this study is to investigate anti-inflammatory effect and immune responses of aqueous extract from Fructus Chaenomelis (FC). Methods: We studied anti-inflammatory effect by means of examining the production of NO(nitric oxide) and expressions of pro-inflammatory cytokine (TNF-$\alpha$(tumor necrosis factor-alpha), IL(Interleukin)-6, IL-12) in the LPS-induced peritoneal macrophages of mice. Also, The western blot analysis has been done to look into the mechanism of anti-inflammatory effect. Results: 1. The FC extract did not have any cytotoxicity in the peritoneal macrophages. 2. The FC extract inhibits the productions of NO, IL-6. IL-12 in the LPS-stimulated peritoneal macrophages of mice, but not of TNF-$\alpha$. 3. The FC extract inhibits the activation of NF-${\kappa}B$(nuclear factor-kappa B) by keeping $I{\kappa}B-\alpha$(inhibitory kappa B-alpha) from degradating, but not of MAPKs(mitogen-activated protein kinases) such as ERK(extracelluar signa 1-regulated kinase), JNK(c-Jun N-terminal kinase), p38. Conclusion: These results show that FC extract inhibits the production of pro-inflammatory cytokines such as IL-6. IL-12. NO by inhibiting NF-${\kappa}B$ activation in the peritoneal macrophages of mice. In conclusion, this experiment suggests that FC extract may be effective for the treatment of acute and chronic inflammation including genitourinary infection.

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The Inhibitory Effect of Lycii Fructus on LPS-stimulated NF-${\kappa}B$ Activation and iNOS Expression in RAW 264.7 Macrophages

  • Kim, Beum-Seuk;Song, Yun-Kyung;Lim, Hyung-Ho
    • The Journal of Korean Medicine
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    • v.29 no.1
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    • pp.47-59
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    • 2008
  • Objective : Anti-inflammatory effects of the extract of Lycii Fructus on lipopolysaccharide (LPS)-induced inflammation in RAW 264.7 macrophage cells were investigated. Method : In order to assess the cytotoxic effect of Lycii Fructus on the raw 264.7 macrophages 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) assay was performed. Reverse transcription-polymerase chain reaction(RT-PCR) analysis of the mRNA levels of tumor necrosis factor-$\alpha$(TNF-$\alpha$) and inducible nitric oxide synthase(iNOS) was performed in order to provide an estimate of the relative level of expression of these genes. The protein level of the inhibitor of nuclear factor-${\kappa}B(I{\kappa}B)$ and nuclear factor-${\kappa}B$(NF-${\kappa}B$) activity was investigated by Western blot assay. NO production was investigated by NO detection. Result : Lycii Fructus suppressed NO production by inhibiting the LPS-induced expressions of iNOS and TNF-$^-\alpha$ mRNA and iNOS protein in RAW 264.7 macrophage cells. Also, Lycii Fructus suppressed activation of NF-${\kappa}B$ in the nucleus. Conclusion : These results show that the extract of Lycii Fructus has anti-inflammatory effect probably by suppressing iNOS expressions through the down-regulation of NF-${\kappa}B$ binding activity.

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Anti-allergic Effect of Bopyeoyangyeong-jun to Cytokines and Transcription (보폐양영전(保肺養營煎)이 알레르기 염증반응에서 Cytokines 및 Transcription에 미치는 영향)

  • Lee, Jae-Hyuk;Kim, Hong-Gi;Shin, Woo-Jin;Kim, Jin-Young;Park, Dong-Il
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.23 no.1
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    • pp.127-134
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    • 2009
  • In the present study, we investigated the anti-allergic effect of the water extract of Bopyeoyangyeong-jun(BYJ) to cytokines and transcription. To investigate the biological effect of BYJ, We examined cytotoxicity and inflammatory cytokine secretion with RBL-2H3. We examined tumor necrosis factor-alpha(TNF-$\alpha$), interleukin(IL)-4 secretion from RBL-2H3 cell after pre- treatment with Bopyeoyangyeong-jun of $1\;mg/m{\ell}$, $2\;mg/m{\ell}$. RBL-2H3 cell was stimulated with phorbol 12-myristate 13-acetate(PMA) and calcium ionophore A23187. We observed that Bopyeoyangyeong-jun reduced TNF-$\alpha$, IL-4 secretion and mRNA expression in RBL-2H3 cells. Moreover, the expression of levels of cyclooxygenase (COX)-2 mRNA, nuclear factor-kappa B (NF-${\kappa}B$) (p65) protein, ERK MAPK, and the degradation of level inhibitor kappa B-alpha ($I{\kappa}B-{\alpha}$) were down-regulated by BYJ. Taken together, these results indicate that Bopyeoyangyeong-jun hascontrols TNF-$\alpha$, IL-4 secretion on allergic reaction.

Resveratrol Inhibits Nitric Oxide-Induced Apoptosis via the NF-Kappa B Pathway in Rabbit Articular Chondrocytes

  • Eo, Seong-Hui;Cho, Hongsik;Kim, Song-Ja
    • Biomolecules & Therapeutics
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    • v.21 no.5
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    • pp.364-370
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    • 2013
  • Resveratrol (trans-3,4'-trihydroxystillbene), a naturally occurring polyphenolic antioxidant found in grapes and red wine, elicits diverse biochemical responses and demonstrates anti-aging, anti-inflammatory, and anti-proliferative effects in several cell types. Previously, resveratrol was shown to regulate differentiation and inflammation in rabbit articular chondrocytes, while the direct production of nitric oxide (NO) in these cells by treatment with the NO donor sodium nitroprusside (SNP) led to apoptosis. In this study, the effect of resveratrol on NO-induced apoptosis in rabbit articular chondrocytes was investigated. Resveratrol dramatically reduced NO-induced apoptosis in chondrocytes, as determined by phase-contrast microscopy, the MTT assay, FACS analysis, and DAPI staining. Treatment with resveratrol inhibited the SNP-induced expression of p53 and p21 and reduced the expression of procaspase-3 in chondrocytes, as detected by western blot analysis. SNP-induced degradation of I-kappa B alpha ($I{\kappa}B-{\alpha}$) was rescued by resveratrol treatment, and the SN50 peptide-mediated inhibition of NF-kappa B (NF-${\kappa}B$) activity potently blocked SNP-induced caspase-3 activation and apoptosis. Our results suggest that resveratrol inhibits NO-induced apoptosis through the NF-${\kappa}B$ pathway in articular chondrocytes.

Activity and Expression Pattern of NF-κB/P65 in Peripheral Blood from Hepatocellular Carcinoma Patients - Link to Hypoxia Inducible Factor -1α

  • Gaballah, Hanaa Hibishy;Zakaria, Soha Said;Ismail, Saber Abdelrahman
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.16
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    • pp.6911-6917
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    • 2014
  • Background: Hepatocellular carcinoma is a complex and heterogeneous tumor with poor prognosis due to frequent intrahepatic spread and extrahepatic metastasis. The molecular mechanisms underlying HCC pathogenesis still remain obscure. Objectives: We aimed to investigate the abundance and the DNA binding activity of nuclear factor kappa B/p65 subunit in peripheral blood mononuclear cells from patients with HCC and to assess its prognostic significance and association with hypoxia inducible factor one alpha (HIF-$1{\alpha}$) in blood. Subjects and methods: This study was carried out on 40 patients classified equally into liver cirrhosis (group I) and HCC (group II), in addition to 20 healthy volunteers (group III). All groups were subjected to measurement of NF-${\kappa}B$/P65 subunit expression levels by real time-PCR, and DNA binding activity was evaluated by transcription factor binding immunoassay. Serum HIF-$1{\alpha}$ levels were estimated by enzyme-linked immunosorbent assay (ELISA). Significant increase of both the expression level and DNA binding activity of NF-${\kappa}B$/P65 subunit together with serum HIF-1 alpha levels was noted in HCC patients compared to liver cirrhosis and control subjects, with significant positive correlation with parameters for bad prognosis of HCC. In conclusion, NF-${\kappa}B$ signaling is activated in HCC and associated with disease prognosis and with high circulating levels of HIF-1 alpha.

Blockade of p38 Mitogen-activated Protein Kinase Pathway Inhibits Interleukin-6 Release and Expression in Primary Neonatal Cardiomyocytes

  • Chae, Han-Jung;Kim, Hyun-Ki;Lee, Wan-Ku;Chae, Soo-Wan
    • The Korean Journal of Physiology and Pharmacology
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    • v.6 no.6
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    • pp.319-325
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    • 2002
  • The induction of interleukin-6 (IL-6) using combined proinflammatory agents $(LPS/IFN-{\gamma}\;or\;TNF-{\alpha}/IFN-{\gamma})$ was studied in relation to p38 mitogen-activated protein kinase (MAPK) and $NF-{\kappa}B$ transcriptional factor in primary neonatal cardiomyocytes. When added to cultures of cardiomyocytes, the combined agents $(LPS/IFN-[\gamma}\;or\;TNF-{\alpha}/IFN-{\gamma})$ had stimulatory effect on the production of IL-6 and the elevation was significantly reduced by SB203580, a specific p38 MAPK inhibitor. SB203580 inhibited protein production and gene expression of IL-6 in a concentration-dependent manner. In this study, $IFN-{\gamma}$ enhancement of $TNF-{\alpha}-induced\;NF-{\kappa}B$ binding affinity as well as p38 MAP kinase activation was observed. However, a specific inhibitor of p38 MAPK, SB203580, had no effect on $TNF-{\alpha}/IFN-{\gamma}\;or\;LPS/IFN-{\gamma}-induced\;NF-{\kappa}B$ activation. This study strongly suggests that these pathways about $TNF-{\alpha}/IFN-{\gamma}$ or $LPS/IFN-{\gamma}-activated$ IL-6 release can be primarily dissociated in primary neonatal cardiomyocytes.