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

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Immunostimulatory Activities of Polysaccharides from Liquid Culture of Pine-Mushroom Tricholoma matsutake

  • Kim, Joo-Young;Byeon, Se-Eun;Lee, Yong-Gyu;Lee, Ji-Yeon;Park, Jong-Sun;Hong, Eock-Ki;Cho, Jae-Youl
    • Journal of Microbiology and Biotechnology
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    • v.18 no.1
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    • pp.95-103
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    • 2008
  • Mushrooms are regarded as one of the well-known foods and biopharmaceutical materials with a great deal of interest. Polysaccharide ${\beta}$-glucan is the major component of mushrooms that displays various biological activities such as antidiabetic, anticancer, and antihyperlipidemic effects. In this study, we compared the immunostimulatory potency of polysaccharide fractions, prepared from liquid culture of pine-mushroom Tricholoma matsutake, with a potent immunogen lipopolysaccharide (LPS), and their molecular mechanisms on the functional activation of macrophages. We found that fraction II (TMF-II) was able to comparably upregulate or highly enhance the phenotypic functions of macrophages such NO production and cytokine (IL-$1{\beta}$, IL-6, IL-12, and TNF-${\alpha}$) expression, to LPS. TMF-II triggered the phosphorylation of $I{\kappa}B{\alpha}$, a critical step for NF-${\kappa}B$ activation and translocation. Of the upstream signaling enzymes tested, Src and Akt were thought to be the responsible upstream signaling components in induction of NO production, although TMF-II strongly upregulated the phosphorylation of all MAPK pathways. Therefore, our data suggest that T. matsutake-derived ${\beta}$-glucan may exert its immunostimulating activities with similar potency to LPS via activation of multiple signaling pathways linked to NF-${\kappa}B$ activation.

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.

Inhibition of Dermatitis Development by Sopungsan in Nc/Nga Mice

  • Pokhare, Yuba Raj;Lim, Sung-Chul;Kim, Sang-Chan;Choi, Hoo-Kyun;Kang, Keon-Wook
    • Toxicological Research
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    • v.24 no.1
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    • pp.17-22
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    • 2008
  • Sopungsan (SS) is a traditional Korean decoction used for the treatment of dermatitis. The aim of this study is to confirm whether or not SS has a preventive effect on the development of atopic dermatitis in dinitrochlorobenzene-applied Nc/Nga mice. SS was administered orally to Nc/Nga mice, which led to the remarkable suppression of the development of dermatitis, as determined by a histological examination and the serum IgE levels. Moreover, SS inhibited the production of thymus- and activation-regulated chemokine (TARC) and its mRNA expression in a keratinocyte cell line, HaCaT, which had been stimulated with tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) and interferon-${\gamma}$ (IFN-${\gamma}$). Activation of the nuclear factor-${\kappa}B$ (NF-${\kappa}B$) or activator protein-1 (AP-1) is one of key steps in the signaling pathways mediating induction of TARC. In this study, SS selectively suppressed NF-${\kappa}B$ activation which may be essential for TARC expression in $TNF-{\alpha}/IFN-{\gamma}$ treated keratinocytes. The inhibitory effect of SS on NF-${\kappa}B$ activation and TARC production might be associated with the anti-dermatitic effects of SS.

NF-${\kappa}B$ and CREB Are Involved in IL-8 Production of Human Neutrophils Induced by Trichomonas vaginalis-Derived Secretory Products

  • Nam, Young-Hee;Min, Deul-Le;Park, Soon-Jung;Kim, Kyeong-Ah;Lee, Young-Ah;Shin, Myeong-Heon
    • Parasites, Hosts and Diseases
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    • v.49 no.3
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    • pp.291-294
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    • 2011
  • Trichomonas vaginalis is a flagellated lumen-dwelling extracellular protozoan parasite that causes human trichomoniasis via sexual intercourse. Human neutrophils play a crucial role in acute tissue inflammatory responses in T. vaginalis infection. In this study, we investigated the signaling mechanism of neutrophil responses when stimulated with T. vaginalis-derived secretory products (TvSP), which were collected from $1{\times}10^7$ live trichomonads. Incubation of human neutrophils isolated from peripheral blood with TvSP induced up-regulation of IL-8 protein secretion. In addition, stimulation with TvSP induced phosphorylation of NF-${\kappa}B$ and CREB in neutrophils. Moreover, TvSP-induced IL-8 production was also significantly inhibited by pretreatment of neutrophils with $i{\kappa}B$ inhibitor or CREB inhibitor. These results suggest that transcription factors NF-${\kappa}B$ and CREB are involved in IL-8 production in human neutrophils induced by stimulation with T. vaginalis infection.

Sec-O-glucosylhamaudol mitigates inflammatory processes and autophagy via p38/JNK MAPK signaling in a rat neuropathic pain model

  • Oh, Seon Hee;Kim, Suk Whee;Kim, Dong Joon;Kim, Sang Hun;Lim, Kyung Joon;Lee, Kichang;Jung, Ki Tae
    • The Korean Journal of Pain
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    • v.34 no.4
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    • pp.405-416
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    • 2021
  • Background: This study investigated the effect of intrathecal Sec-O-glucosylhamaudol (SOG) on the p38/c-Jun N-terminal kinase (JNK) signaling pathways, nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB)-related inflammatory responses, and autophagy in a spinal nerve ligation (SNL)-induced neuropathic pain model. Methods: The continuous administration of intrathecal SOG via an osmotic pump was performed on male Sprague-Dawley rats (n = 50) with SNL-induced neuropathic pain. Rats were randomized into four groups after the 7th day following SNL and treated for 2 weeks as follows (each n = 10): Group S, sham-operated; Group D, 70% dimethylsulfoxide; Group SOG96, SOG at 96 ㎍/day; and Group SOG192, SOG at 192 ㎍/day. The paw withdrawal threshold (PWT) test was performed to assess neuropathic pain. Western blotting of the spinal cord (L5) was performed to measure changes in the expression of signaling pathway components, cytokines, and autophagy. Additional studies with naloxone challenge (n = 10) and cells were carried out to evaluate the potential mechanisms underlying the effects of SOG. Results: Continuous intrathecal SOG administration increased the PWT with p38/JNK mitogen-activated protein kinase (MAPK) pathway and NF-κB signaling pathway inhibition, which induced a reduction in proinflammatory cytokines with the concomitant downregulation of autophagy. Conclusions: SOG alleviates mechanical allodynia, and its mechanism is thought to be related to the regulation of p38/JNK MAPK and NF-κB signaling pathways, associated with autophagy during neuroinflammatory processes after SNL.

STP-C, an Oncoprotein of Herpesvirus saimiri Augments the Activation of NF-κB through Ubiquitination of TRAF6

  • Chung, Young-Hwa;Jhun, Byung-Hak;Ryu, Su-Chak;Kim, Heui-Soo;Kim, Cheol-Min;Kim, Bong-Seok;Kim, Young-Ok;Lee, Sang-Jun
    • BMB Reports
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    • v.40 no.3
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    • pp.341-348
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    • 2007
  • Herpesvirus saimiri (HVS), a member of the $\delta$-herpesvirus family, encodes an oncoprotein called Saimiri Transforming Protein (STP) which is required for lymphoma induction in non-human primates. Previous study has shown that STP-C, an oncoprotein of HVS, activates NF-$\kappa$B signaling pathway. However, the detailed mechanism of STP-Cmediated NF-$\kappa$B activation has not been reported yet. We first report that STP-C interacts with TRAF6 protein in vivo and in vitro and further investigation shows that $Glu_{12}$ residue of STP-C is critical for binding to TRAF6. Introduction of ubiquitin together with STP-C augments NF-$\kappa$B activity compared to that of STP-C expression alone. STP-C expression further induces ubiquitination of endogenous TRAF6. In addition, either a deubiquitination enzyme, CYLD or a dominant negative E2-conjugation enzyme reduced NF-$\kappa$B activity in spite of the presence of STP-C, supporting that the interaction between STP-C and TRAF6 induces ubiquitination of TRAF6. NF-$\kappa$B activation by STP-C through the ubiquitinated TRAF6 causes the increased production of IL-8, an inflammatory chemokine and the enhanced expression of costimulatory molecule ICAM, which might ultimately contribute cellular transformation by the exposure of HVS-infected cells with inflammatory microenvironment and chronic activation.

Degradation of the Transcription Factors NF-${\kappa}B$, STAT3, and STAT5 Is Involved in Entamoeba histolytica-Induced Cell Death in Caco-2 Colonic Epithelial Cells

  • Kim, Kyeong Ah;Min, Arim;Lee, Young Ah;Shin, Myeong Heon
    • Parasites, Hosts and Diseases
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    • v.52 no.5
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    • pp.459-469
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    • 2014
  • Entamoeba histolytica is a tissue-invasive protozoan parasite causing dysentery in humans. During infection of colonic tissues, amoebic trophozoites are able to kill host cells via apoptosis or necrosis, both of which trigger IL-8-mediated acute inflammatory responses. However, the signaling pathways involved in host cell death induced by E. histolytica have not yet been fully defined. In this study, we examined whether calpain plays a role in the cleavage of pro-survival transcription factors during cell death of colonic epithelial cells, induced by live E. histolytica trophozoites. Incubation with amoebic trophozoites induced activation of m-calpain in a time- and dose-dependent manner. Moreover, incubation with amoebae resulted in marked degradation of STAT proteins (STAT3 and STAT5) and NF-${\kappa}B$ (p65) in Caco-2 cells. However, $I{\kappa}B$, an inhibitor of NF-${\kappa}B$, was not cleaved in Caco-2 cells following adherence of E. histolytica. Entamoeba-induced cleavage of STAT proteins and NF-${\kappa}B$ was partially inhibited by pretreatment of cells with a cell-permeable calpain inhibitor, calpeptin. In contrast, E. histolytica did not induce cleavage of caspase-3 in Caco-2 cells. Furthermore, pretreatment of Caco-2 cells with a calpain inhibitor, calpeptin (but not the pan-caspase inhibitor, z-VAD-fmk) or m-calpain siRNA partially reduced Entamoeba-induced DNA fragmentation in Caco-2 cells. These results suggest that calpain plays an important role in E. histolytica-induced degradation of NF-${\kappa}B$ and STATs in colonic epithelial cells, which ultimately accelerates cell death.

Protein Kinase $C-{\alpha}$ Regulates Toll-like Receptor 4-Mediated Inducible Nitric Oxide Synthase Expression

  • Lee, Jin-Gu;Chin, Byung-Rho;Baek, Suk-Hwan
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.34 no.1
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    • pp.28-35
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    • 2008
  • Purpose: The nitric oxide (NO) release by inducible nitric oxide synthase (iNOS) is the key events in macrophage response to lipopolysaccharide (LPS) which is suggested to be a crucial mediator for inflammatory and innate immune responses. NO is an important mediator involved in many host defense action and may also lead to a harmful host response to bacterial infection. However, given the importance of iNOS in a variety of pathophysiological conditions, control of its expression and signaling events in response to LPS has been the subject of considerable investigation. Materials and Methods: The Raw264.7 macrophage cell line was used to observe LPS-stimulated iNOS expression. The expression of iNOS is observed by Western blot analysis and real-time RT-PCR. Protein kinase C $(PKC)-{\alpha}$ overexpressing Raw264.7 cells are established to determine the involvement of $PKC-{\alpha}$ in LPS-mediated iNOS expression. $NF-{\kappa}B$ activity is measured by $I{\kappa}B{\alpha}$ degradation and $NF-{\kappa}B$ luciferase activity assay. Results: We found that various PKC isozymes regulate LPS-induced iNOS expression at the transcriptional and translational levels. The involvement of $PKC-{\alpha}$ in LPS-mediated iNOS induction was further confirmed by increased iNOS expression in $PKC-{\alpha}$ overexpressing cells. $NF-{\kappa}B$ dependent transactivation by LPS was observed and $PKC-{\alpha}$ specific inhibitory peptide abolished this activation, indicating that $NF-{\kappa}B$ activation is dependent on $PKC-{\alpha}$. Conclusion: Our data suggests that $PKC-{\alpha}$ is involved in LPS-mediated iNOS expression and that its downstream target is $NF-{\kappa}B$. Although $PKC-{\alpha}$ is a crucial mediator in the iNOS regulation, other PKC isozymes may contribute LPS-stimulated iNOS expression. This finding is needed to be elucidated in further study.

Anti-inflammatory activities of Scolopendra subspinipes mutilans in RAW 264.7 cells (RAW 264.7 세포에서 왕지네 추출물의 항염 활성)

  • Park, Jae Hyeon;Lee, Sun Ryung
    • Journal of Nutrition and Health
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    • v.51 no.4
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    • pp.323-329
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    • 2018
  • Purpose: The dried body of Scolopendra subspinipes mutilans has long been used as a traditional Korean medicinal food, but little is known about its mechanisms of action. In this study, we investigated the anti-inflammatory activities of Scolopendra subspinipes mutilans and possible mechanisms in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. Methods: Cytotoxicity of Scolopendra subspinipes mutilans extract (SSME) was measured by MTT assay, anti-inflammatory activities were analyzed by nitric oxide (NO) production, the expression of inducible NO synthase (iNOS) and the mRNA level of pro-inflammatory cytokines such as $interleukin-1{\beta}$ ($IL-1{\beta}$) and interleukin-6 (IL-6). Nuclear translocation of nuclear factor-kappa B ($NF-{\kappa}B$) p65 subunit and degradation of inhibitory kappa B ($I{\kappa}B$) were examined by western blot. Results: SSME inhibited LPS-induced NO production and iNOS expression without cytotoxicity. Up-regulation of LPS-induced pro-inflammatory cytokines, $IL-1{\beta}$ and IL-6 was dose dependently attenuated by SSME. Exposure of pyrrolidine dithiocarbamate, an $NF-{\kappa}B$ specific inhibitor, accelerated the inhibitory effects of SSME on NO production and iNOS expression in LPS-stimulated cells. Moreover, translocation of $NF-{\kappa}B$ from the cytosol to the nucleus and degradation of $I{\kappa}B$ were decreased by treatment with SSME in LPS-induced cells. Conclusion: These results suggest that the SSME might have the inhibitory effects on inflammation, partly through inhibition of the $NF-{\kappa}B$ signaling pathway.

Inhibitory effect of broccoli leaf extract on PGE2 production by NF-κB inhibition (NF-κB 저해를 통한 브로콜리 잎 추출물의 PGE2 저해효과)

  • Park, Sook Jahr;An, Iseul;Noh, Gyu Pyo;Yoo, Byung Hyuk;Lee, Jong Rok
    • The Korea Journal of Herbology
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    • v.34 no.6
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    • pp.117-124
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    • 2019
  • Objective : Broccoli is edible green plant that has a wide variety of health benefits including cancer prevention and cholesterol reduction. However, leaves of broccoli are not eaten and are mostly left as waste. This study was conducted to evaluate the effects of the broccoli leaf extract (BLE) on prostaglandin E2 (PGE2) production related to nuclear factor kappa B (NF-κB) signaling in lipopolysaccharide (LPS)-activated macrophages. Methods : BLE was prepared by extracting dried leaf with ethanol. Cell viability was determined by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. PGE2 and inflammatory cytokines were detected by enzyme-linked immunosorbent assay (ELISA). Expression level of each protein was monitored by Western blot analysis. Results : In LPS-activated Raw264.7 cells, PGE2 release into culture medium was dramatically enhanced compared to control cells. However, increased PGE2 was attenuated dose-dependently by treatment with BLE. Inhibition of PGE2 production by BLE was due to the suppression of cyclooxygenase-2 (COX-2) expression determined by Western blot analysis. BLE also inhibited the production of inflammatory cytokines such as interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α). Inhibition at PGE2 and cytokine was mediated from inhibition of nuclear translocation of NF-κB due to the repression of inhibitory kappa B alpha (IκBα) phosphorylation and degradation. Conclusion : This study showed that BLE exerted inhibitory activities against PGE2, which is critical for the initiation and resolution of inflammatory responses, and that inhibition of PGE2 was mediated by suppression of NF-κB signaling. These results suggest that the waste broccoli leaves could be used for controlling inflammation.