• Title/Summary/Keyword: NF-${\kappa}B$ signaling

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Anti-Inflammatory Effect of Rosa rugosa Flower Extract in Lipopolysaccharide-Stimulated RAW264.7 Macrophages

  • Tursun, Xirali;Zhao, Yongxin;Talat, Zulfiya;Xin, Xuelei;Tursun, Adila;Abdulla, Rahima;AkberAisa, Haji
    • Biomolecules & Therapeutics
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    • v.24 no.2
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    • pp.184-190
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    • 2016
  • Rosa rugosa Thunb, a deciduous shrub of the genus Rosa, has been widely used to treat stomach aches, diarrhoea, pain, and chronic inflammatory disease in eastern Asia. In recent years, our research team has extensively studied the Rosa rugosa flower extract, and specifically undertook pharmacological experiments which have optimized the extraction process. Our methods have yielded a standard extract enriched in phenolic compounds, named PRE. Herein, we expand our efforts and evaluated the anti-inflammatory activity of PRE on lipopolysaccharide (LPS)-induced inflammation in RAW 264.7 macrophages. PRE significantly inhibited production of nitric oxide (NO), prostaglandin $E_2(PGE_2)$, tumor necrosis factor (TNF)-${\alpha}$, interleukin (IL)-6, and interleukin $1{\beta}$ (IL-$1{\beta}$), as well as expression of their synthesizing enzymes, inducible nitric oxide synthase (iNOS) and cyclooxygenase2 (COX-2). Furthermore, PRE inhibited activity of mitogen-activated protein kinases (MAPK) as well as nuclear factor-kappa B (NF-${\kappa}B$) signaling pathway. Our findings are the first to explain the anti-inflammatory mechanism by PRE in LPS-stimulated macrophages. Given these results, we propose that PRE has therapeutic potential in the prevention of inflammatory disorders.

KMS99220 Exerts Anti-Inflammatory Effects, Activates the Nrf2 Signaling and Interferes with IKK, JNK and p38 MAPK via HO-1

  • Lee, Ji Ae;Kim, Dong Jin;Hwang, Onyou
    • Molecules and Cells
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    • v.42 no.10
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    • pp.702-710
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    • 2019
  • Neuroinflammation is an important contributor to the pathogenesis of neurodegenerative disorders including Parkinson's disease (PD). We previously reported that our novel synthetic compound KMS99220 has a good pharmacokinetic profile, enters the brain, exerts neuroprotective effect, and inhibits $NF{\kappa}B$ activation. To further assess the utility of KMS99220 as a potential therapeutic agent for PD, we tested whether KMS99220 exerts an anti-inflammatory effect in vivo and examined the molecular mechanism mediating this phenomenon. In 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-treated mice, oral administration of KMS99220 attenuated microglial activation and decreased the levels of inducible nitric oxide synthase and interleukin 1 beta ($IL-1{\beta}$) in the nigrostriatal system. In lipopolysaccharide (LPS)-challenged BV-2 microglial cells, KMS99220 suppressed the production and expression of $IL-1{\beta}$. In the activated microglia, KMS99220 reduced the phosphorylation of $I{\kappa}B$ kinase, c-Jun N-terminal kinase, and p38 MAP kinase; this effect was mediated by heme oxygenase-1 (HO-1), as both gene silencing and pharmacological inhibition of HO-1 abolished the effect of KMS99220. KMS99220 induced nuclear translocation of the transcription factor Nrf2 and expression of the Nrf2 target genes including HO-1. Together with our earlier findings, our current results show that KMS99220 may be a potential therapeutic agent for neuroinflammation-related neurodegenerative diseases such as PD.

Cytochalasin B Modulates Macrophage-Mediated Inflammatory Responses

  • Kim, Mi-Yeon;Kim, Jong-Hoon;Cho, Jae Youl
    • Biomolecules & Therapeutics
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    • v.22 no.4
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    • pp.295-300
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    • 2014
  • The actin cytoskeleton plays an important role in macrophage-mediated inflammatory responses by modulating the activation of Src and subsequently inducing nuclear factor (NF)-${\kappa}B$ translocation. In spite of its critical functions, few papers have examined how the actin cytoskeleton can be regulated by the activation of toll-like receptor (TLR). Therefore, in this study, we further characterized the biological value of the actin cytoskeleton in the functional activation of macrophages using an actin cytoskeleton disruptor, cytochalasin B (Cyto B), and explored the actin cytoskeleton's involvement in morphological changes, cellular attachment, and signaling events. Cyto B strongly suppressed the TLR4-mediated mRNA expression of inflammatory genes such as cyclooxygenase (COX)-2, tumor necrosis factor (TNF)-${\alpha}$, and inducible nitric oxide (iNOS), without altering cell viability. This compound also strongly suppressed the morphological changes induced by lipopolysaccharide (LPS), a TLR4 ligand. Cyto B also remarkably suppressed NO production under non-adherent conditions but not in an adherent environment. Cyto B did not block the co-localization between surface glycoprotein myeloid differentiation protein-2 (MD2), a LPS signaling glycoprotein, and the actin cytoskeleton under LPS conditions. Interestingly, Cyto B and PP2, a Src inhibitor, enhanced the phagocytic uptake of fluorescein isothiocyanate (FITC)-dextran. Finally, it was found that Cyto B blocked the phosphorylation of vasodilator-stimulated phosphoprotein (VASP) at 1 min and the phosphorylation of heat shock protein 27 (HSP27) at 5 min. Therefore, our data suggest that the actin cytoskeleton may be one of the key components involved in the control of TLR4-mediated inflammatory responses in macrophages.

Possible roles of amyloid intracellular domain of amyloid precursor protein

  • Chang, Keun-A;Suh, Yoo-Hun
    • BMB Reports
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    • v.43 no.10
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    • pp.656-663
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    • 2010
  • Amyloid precursor protein (APP), which is critically involved in the pathogenesis of Alzheimer's disease (AD), is cleaved by gamma/epsilon-secretase activity and results in the generation of different lengths of the APP Intracellular C-terminal Domain (AICD). In spite of its small size and short half-life, AICD has become the focus of studies on AD pathogenesis. Recently, it was demonstrated that AICD binds to different intracellular binding partners ('adaptor protein'), which regulate its stability and cellular localization. In terms of choice of adaptor protein, phosphorylation seems to play an important role. AICD and its various adaptor proteins are thought to take part in various cellular events, including regulation of gene transcription, apoptosis, calcium signaling, growth factor, and $NF-{\kappa}B$ pathway activation, as well as the production, trafficking, and processing of APP, and the modulation of cytoskeletal dynamics. This review discusses the possible roles of AICD in the pathogenesis of neurodegenerative diseases including AD.

The Role of Nrf2 in Cellular Innate Immune Response to Inflammatory Injury

  • Kim, Ji-Young;Surh, Young-Joon
    • Toxicological Research
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    • v.25 no.4
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    • pp.159-173
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    • 2009
  • Nuclear factor erythroid derived 2-related factor-2 (Nrf2) is a master transcription regulator of antioxidant and cytoprotective proteins that mediate cellular defense against oxidative and inflammatory stresses. Disruption of cellular stress response by Nrf2 deficiency causes enhanced susceptibility to infection and related inflammatory diseases as a consequence of exacerbated immune-mediated hypersensitivity and autoimmunity. The cellular defense capacity potentiated by Nrf2 activation appears to balance the population of $CD4^+$ and $CD8^+$ of lymph node cells for proper innate immune responses. Nrf2 can negatively regulate the activation of pro-inflammatory signaling molecules such as p38 MAPK, NF-${\kappa}B$, and AP-1. Nrf2 subsequently functions to inhibit the production of pro-inflammatory mediators including cytokines, chemokines, cell adhesion molecules, matrix metalloproteinases, COX-2 and iNOS. Although not clearly elucidated, the antioxidative function of genes targeted by Nrf2 may cooperatively regulate the innate immune response and also repress the expression of pro-inflammatory mediators.

NMR Characterization of Oxidized Form of Human 8-kDa Dynein Light Chain

  • Shin, Jae-Sun;Jeong, Woo-Jin;Chi, Seung-Wook
    • Journal of the Korean Magnetic Resonance Society
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    • v.14 no.2
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    • pp.127-133
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    • 2010
  • Redox-dependent conformational change of human 8-kDa Dynein light chain (LC8) plays important role in regulating NF-${\kappa}B$ signaling pathway. In this study we characterized the structural states of the oxidized and reduced forms of LC8 by using NMR spectroscopy. The $^1H-^{15}N$ 2D HSQC spectra of oxidized LC8 indicated that no significant change in tertiary structure of LC8 occurred upon oxidation. The chemical shift perturbations of LC8 upon oxidation suggest a redox-dependent quaternary structural change.

Positive and negative regulation of the Drosophila immune response

  • Aggarwal, Kamna;Silverman, Neal
    • BMB Reports
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    • v.41 no.4
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    • pp.267-277
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    • 2008
  • Insects mount a robust innate immune response against a wide array of microbial pathogens. The hallmark of the Drosophila humoral immune response is the rapid production of anti-microbial peptides in the fat body and their release into the circulation. Two recognition and signaling cascades regulate expression of these antimicrobial peptide genes. The Toll pathway is activated by fungal and many Gram-positive bacterial infections, whereas the immune deficiency (IMD) pathway responds to Gram-negative bacteria. Recent work has shown that the intensity and duration of the Drosophila immune response is tightly regulated. As in mammals, hyperactivated immune responses are detrimental, and the proper down-modulation of immunity is critical for protective immunity and health. In order to keep the immune response properly modulated, the Toll and IMD pathways are controlled at multiple levels by a series of negative regulators. In this review, we focus on recent advances identifying and characterizing the negative regulators of these pathways.