• Title/Summary/Keyword: IkB kinase (IKK)

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The Study of $NF-{\kappa}B(P50)$ Suppression mechanism with main Component of Bee Venom and Melittin on Human Synoviocyte

  • Kwon, Soon-Jung;Song, Ho-Sueb
    • Journal of Acupuncture Research
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    • v.22 no.2
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    • pp.123-132
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    • 2005
  • Melittin,cationic 26-amino acid, is the principal component of the bee venom (BV) which has been used for treatment of inflammatory disease such as arthritis rheumatism NF-kB is activated by subsequent release of inhibitory IkB via activation of a multisubunit IkB kinase (IKK). We previously found that melittin bind to the sulfhydryl group of p50, a subunit of NF-kB. Since sulfhydryl group is present in kinase domain of IKKa and IKKb, melittin could modify IKK activity by protein-protein interaction. We therefore examined effect of melittin on IKK activities in sodium nitroprusside (SNP)-stimulated synoviocyte obtained from RA patients. Melittin suppressed the SNP-induced release of IkB resulted in inhibition of DNA binding activity of NF-kB and NF-kB-dependent luciferase activity. Consistent with the inhibitory effect on NF-kB activation, IKKa and IKKb activities were also suppressed by melittin. Surface plasmon resonance analysis realized that melitin binds to IKKa $(Kd\;=\;1.34{\times}10-9M)$ and IKKb$(Kd\;=\;1.0{\times}10-9M)$. Inhibition of IKKa and IKKb resulted in reduction of the SNP-induced production of inflammatory mediators NO and PGE2 generation. The inhibitory effect of melittin on the IKKs activities, binding affinity of melittin to IKKs, and NO and PGE2 generation were blocked by addition of reducing agents dithiothreitol and glutathione. In addition, melittin did not show inhibitory effect in the transfected Synoviocytes with plasmid carrying dominant negative mutant IKKa (C178A) and IKKb (C179A). These results demonstrate that melittin directly binds to sulfhydryl group of IKKs resulting in IkBrelease, thereby inhibits activation of NF-kB and expression of genes involving in the inflammatory responses.

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Lonicera Japonioa Inhibits the Production of NO through the Suppression of NF-kB Activity in LPS-stimulated Mouse Peritoneal Macrophages

  • Kim Young-hee;Kim Han-do
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.17 no.1
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    • pp.163-171
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    • 2004
  • The flowers of Lonicera japonica Thunb. (Caprifoliaceae) has been used as anti-inflammatory drug in the folk medicine recipe and been proved its anti-inflammatory effect in the oriental medicine. However, the action mechanism of Lonicera japonica that exhibits anti-inflammatory effects has not been determined. Since nitric oxide (NO) is one of the major inflammatory parameter, we studied the effect of aqueous extracts of Lonicera japonica (AELJ) on NO production in lipopolysaccharide (LPS)-stimulated mouse peritoneal macrophages. NO and inducible NO synthase (iNOS) level were significantly reduced in LPS-stimulated macrophages by AELJ compared to those without Electrophoretic mobility shift assay (EMSA) indicated that AELJ blocked the activation of nuclear factor kappa B (NF-kB), which was considered to be a potential transcription factor for the iNOS expression. AELJ also blocked the phosphorylation and degradation of inhibitor of kappa B-alpha (IkB-${\alpha}$). Furthermore, IkB kinase alpha (IKK${\alpha}$), which is known to phosphorylate serine residues of IkB directly, is inhibited by AELJ in vivo and in vitro. These results suggest that AELJ could exert its anti-inflammatory actions by suppressing the synthesis of NO through inhibition of NF-kB activity.

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Sodium Salicylate Inhibits Expression of COX-2 Through Suppression of ERK and Subsequent $NF-{\kappa}B$ Activation in Rat Ventricular Cardiomyocytes

  • Kwon, Keun-Sang;Chae, Han-Jung
    • Archives of Pharmacal Research
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    • v.26 no.7
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    • pp.545-553
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    • 2003
  • The expression of cyclooxygenase-2 (COX-2) is a characteristic response to inflammation, which can be inhibited with sodium salicylate. IL-1$\beta$ and TNF-$\alpha$ can induce extracellular signal-regulated kinase (ERK), IKK, IkB degradation and NF-$\kappa$B activation. Salicylate inhibited the IL-1$\beta$ and TNF-$\alpha$-induced COX-2 expressions, regulated the activation of ERK, IKK and IkB degradation, and the subsequent activation of NF-$\kappa$B, in neonatal rat ventricular cardiomyocytes. The inhibition of the ERK pathway, with a selective inhibitor, PD098059, blocked the expressions of IL-1$\beta$ and TNF-$\alpha$-induced COX-2 and $PGE_2$ release. The antioxidant, N-acetyl-cysteine, also reduced the glutathione or catalase- attenuated COX-2 expressions in IL-1$\beta$ and TNF-$\alpha$-treated cells. This antioxidant also inhibited the activation of ERK and NF-$\kappa$B in neonatal rat cardiomyocytes. In addition, IL-1$\beta$ and TNF-$\alpha$-stimulated the release of reactive oxygen species (ROS) in the cardiomyocytes. However, salicylate had no inhibitory effect on the release of ROS in the DCFDA assay. The results showed that salicylate inhibited the activation of ERK and IKK, I$\kappa$B degradation and NF-$\kappa$B activation, independently of the release of ROS, which suggested that salicylate exerts its anti-inflammatory action through the inhibition of ERK, IKK, IkB and NF-$\kappa$B, and the resultant COX-2 expression pathway in neonatal rat ventricular cardiomyocytes.

Scrophularia Buergeriana inhibits the Production of NO through the Suppression of NF-kB adivity in LPS-stimulated Mouse Peritoneal Macrophages

  • Ha Mi Suk;Kim Young Hee;Ko Woo Shin;Kim Han Do
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.16 no.6
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    • pp.1284-1290
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    • 2002
  • Scrophularia buergeriana Miquel (Scrophulariaceae) has been used as an anti-inflammatory drug in the folk medicine recipe and been proved its anti-inflammatory effect in the oriental medicine. Since nitric oxide (NO) and superoxide anion (O/sub 2//sup -/) are ones of the major inflammatory parameters, we studied the effect of aqueous extracts of Scrophularia buergeriana (SB) on NO and O/sub 2//sup -/ production in lipopolysaccharide (LPS)-stimulated mouse peritoneal macrophages. NO, O/sub 2//sup -/production and inducible NO synthase (iNOS) level were significantly reduced in LPS-activated macrophages by SB compared to those without. Electrophoretic mobility shift assay (EMSA) indicated that SB blocked the activation of NF-kB, which was considered to be a potential transcription factor for the iNOS expression. SB also blocked degradation of IkBα. Furthermore, IkB kinase alpha (IKKα), which phosphorylates serine residues of IkB directly, is inhibited by SB. These results suggest that SB could exert its anti-inflammatory actions by suppressing the activation of NF-kB through inhibition of IKK activity.