• Title/Summary/Keyword: Syk

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Carex pumila Extract Supresses Mast Cell Activation and IgE-Mediated Allergic Response in Mice (좀보리사초의 IgE 매개성 알레르기 반응 억제 효과 및 기전)

  • Lim, Hannah;Kim, Young Mi
    • Journal of Food Hygiene and Safety
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    • v.29 no.4
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    • pp.356-362
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    • 2014
  • Allergic diseases have increased rapidly over the past decades, affecting an estimated 20~30% of the population in developed countries. In this study, we investigated whether or not a typical costal sand dune plant Carex pumila (CPE) suppresses the activation of mast cells and IgE-mediated allergic response in vitro and in vivo. As the results, the extract of Carex pumila inhibited antigen-stimulated degranulation in RBL-2H3 cells and Bone marrow-derived mast cells (BMMCs), and IgE-mediated passive cutaneous anaphylaxis (PCA) in mice. CPE also suppressed the production of pro-inflammatory cytokines, TNF-${\alpha}$ and IL-4, in antigen-stimulated mast cells. As its mechanism of action, CPE inhibited the activation of Syk in $Fc{\varepsilon}RI$-mediated signalling pathway, and that of LAT, a downstream adaptor molecule of Syk, in a dose-dependent manner. CPE also suppressed the activation of mitogen-activated protein (MAP) kinases, p38, ERK1/2, JNK, and Akt. Altogether, CPE inhibited mast cell activation and IgE-mediated allergic response by antigen through suppressing the activation of Syk. These results suggest that CPE may be useful for the treatment of allergic diseases.

Extract of Malus sieboldii Suppresses IgE-mediated Mast Cell Activation through Inhibition of Syk Kinase (아그배나무(Malus sieboldii)의 IgE 매개성 알레르기 반응 억제 효과 및 기전)

  • Jo, So Young;Kim, Young Mi
    • Korean Journal of Pharmacognosy
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    • v.49 no.4
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    • pp.298-304
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    • 2018
  • Malus sieboldii is a dicotyledonous plant that grows widely in Jeju Island and Ganghwa Island in Korea. Malus sieboldii has been known as a detoxifying and antioxidant plant, but study on allergic diseases is not known. In this study, we investigated the effect of Malus sieboldii extract (MSE) on the activation of mast cells, which is well known to be a critical causative cell to induce allergic diseases. As a result of our experiments, MSE inhibited the degranulation and inflammatory cytokine secretion from mast cells by antigen stimulation. As the mechanism of MSE in mast cells, it inhibited the activation of Syk kinase, a essential signaling protein activated by antigen, and further inhibited activation of $PLC{\gamma}$ and MAP kinase(P38, ERK1/2, and JNK). Furthermore, in vivo animal studies showed that MSE significantly inhibited IgE-mediated passive cutaneous anaphylaxis and passive systemic anaphylaxis in a dose-dependent manner. Taken together, the results of this study showed for the first time that MSE inhibited IgE-mediated allergic responses by suppressing Syk kinase in mast cells. Therefore, it could be considered that MSE is worth developing as an anti-allergic material.

Swertia pseudochinensis Methanol Extract Inhibits IgE-mediated Allergic Response In vitro and In vivo (자주쓴풀 메탄올추출물의 IgE-매개 알레르기 반응 억제 및 기전)

  • Jeon, Sun Ha;Kim, Young Mi
    • Korean Journal of Pharmacognosy
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    • v.51 no.4
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    • pp.317-324
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    • 2020
  • Mast cells play a key role in IgE-mediated allergic response. We investigated whether Swertia pseudochinensis Hara extract (SPE) inhibits IgE-mediated allergic response in mast cells and an allergic animal model. Additionally, we explored SPE's mechanism of action in mast cells. Our results showed that SPE inhibited both antigen-stimulated degranulation and the production of TNF-α and IL-4 in bone marrow-derived mast cells (BMMCs) and rat basophilic leukemia (RBL)-2H3 cells. SPE also suppressed allergic response in IgE-mediated passive cutaneous anaphylaxis (PCA) in mice. As for the mechanism of action of SPE in mast cells, it inhibited the activation of Syk kinase, a critical signaling protein in the FcεRI-mediated signaling pathway, and also the activation of LAT, a downstream adaptor protein of Syk. We further observed the reduced activation of mitogen-activated protein (MAP) kinases (P38, ERK1/2, and JNK) and Akt in mast cells. Our results described for the first time that SPE has an anti-allergic effect by suppressing mast cells through the inhibition of Syk kinase. Therefore, SPE may be useful for the treatment of type I allergic diseases.

The Inhibitory Effect of Agrimonia pilosa Ledeb Extract on Allergic Reaction (짚신나물 추출물의 알레르기 반응 억제 효과)

  • Kim, Young-Mi
    • Korean Journal of Medicinal Crop Science
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    • v.18 no.6
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    • pp.398-404
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    • 2010
  • Complementary and alternative medicines are considered as a promising research field to develop new therapies for various allergic diseases. In this study, we investigated the anti-allergic effect of Agrimonia pilosa Ledeb (AP) by using passive cutaneous anaphylaxis in mice and its mechanism of action in mast cells. The extract of AP reversibly inhibited degranulation in RBL-2H3 cells and bone marrow-derived mast cells (BMMCs). AP also suppressed the passive cutaneous anaphylaxis inducing by IgE and antigen (Ag) in a dose-dependent manner. In the study to find its mechanism of action, AP inhibited the phosphorylation of Syk kinase, a pivotal protein which is regulated by Src-family kinase for activation of mast cells. In addition, AP also suppressed activation of Akt and Erk1/2 that are critical for the production of cytokines in mast cells. The results strongly suggest that AP exerts anti-allergic activity in vitro and in vivo through the inhibition of activation of Syk in mast cells.

(E)-3-(3-methoxyphenyl)-1-(2-pyrrolyl)-2-propenone displays suppression of inflammatory responses via inhibition of Src, Syk, and NF-κB

  • Kim, Yong;Jeong, Eun Jeong;Han Lee, In-Sook;Kim, Mi-Yeon;Cho, Jae Youl
    • The Korean Journal of Physiology and Pharmacology
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    • v.20 no.1
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    • pp.91-99
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    • 2016
  • (E)-3-(3-methoxyphenyl)-1-(2-pyrrolyl)-2-propenone (MPP) is an aldol condensation product resulting from pyrrole-2-carbaldehyde and m- and p- substituted acetophenones. However, its biological activity has not yet been evaluated. Since it has been reported that some propenone-type compounds display anti-inflammatory activity, we investigated whether MPP could negatively modulate inflammatory responses. To do this, we employed lipopolysaccharide (LPS)-stimulated macrophage-like RAW264.7 cells and examined the inhibitory levels of nitric oxide (NO) production and transcriptional activation, as well as the target proteins involved in the inflammatory signaling cascade. Interestingly, MPP was found to reduce the production of NO in LPS-treated RAW264.7 cells, without causing cytotoxicity. Moreover, this compound suppressed the mRNA levels of inflammatory genes, such as inducible NO synthase (iNOS) and tumor necrosis factor (TNF)-${\alpha}$. Using luciferase reporter gene assays performed in HEK293 cells and immunoblotting analysis with nuclear protein fractions, we determined that MPP reduced the transcriptional activation of nuclear factor (NF)-${\kappa}B$. Furthermore, the activation of a series of upstream signals for NF-${\kappa}B$ activation, composed of Src, Syk, Akt, and $I{\kappa}B{\alpha}$, were also blocked by this compound. It was confirmed that MPP was able to suppress autophosphorylation of overexpressed Src and Syk in HEK293 cells. Therefore, these results suggest that MPP can function as an anti-inflammatory drug with NF-${\kappa}B$ inhibitory properties via the suppression of Src and Syk.

Britanin Suppresses IgE/Ag-Induced Mast Cell Activation by Inhibiting the Syk Pathway

  • Lu, Yue;Li, Xian;Park, Young Na;Kwon, Okyun;Piao, Donggen;Chang, Young-Chae;Kim, Cheorl-Ho;Lee, Eunkyung;Son, Jong Keun;Chang, Hyeun Wook
    • Biomolecules & Therapeutics
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    • v.22 no.3
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    • pp.193-199
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    • 2014
  • The aim of this study was to determine whether britanin, isolated from the flowers of Inula japonica (Inulae Flos), modulates the generation of allergic inflammatory mediators in activated mast cells. To understand the biological activity of britanin, the authors investigated its effects on the generation of prostaglandin $D_2$ ($PGD_2$), leukotriene $C_4$ ($LTC_4$), and degranulation in IgE/Ag-induced bone marrow-derived mast cells (BMMCs). Britanin dose dependently inhibited degranulation and the generations of $PGD_2$ and $LTC_4$ in BMMCs. Biochemical analyses of IgE/Ag-mediated signaling pathways demonstrated that britanin suppressed the phosphorylation of Syk kinase and multiple downstream signaling processes, including phospholipase $C{\gamma}1$ ($PLC{\gamma}1$)-mediated calcium influx, the activation of mitogen-activated protein kinases (MAPKs; extracellular signal-regulated kinase 1/2, c-Jun $NH_2$-terminal kinase and p38), and the nuclear factor-${\kappa}B$ ($NF-{\kappa}B$) pathway. Taken together, the findings of this study suggest britanin suppresses degranulation and eicosanoid generation by inhibiting the Syk-dependent pathway and britanin might be useful for the treatment of allergic inflammatory diseases.

ST5 Positively Regulates Osteoclastogenesis via Src/Syk/Calcium Signaling Pathways

  • Kim, Min Kyung;Kim, Bongjun;Kwon, Jun-Oh;Song, Min-Kyoung;Jung, Suhan;Lee, Zang Hee;Kim, Hong-Hee
    • Molecules and Cells
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    • v.42 no.11
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    • pp.810-819
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    • 2019
  • For physiological or pathological understanding of bone disease caused by abnormal behavior of osteoclasts (OCs), functional studies of molecules that regulate the generation and action of OCs are required. In a microarray approach, we found the suppression of tumorigenicity 5 (ST5) gene is upregulated by receptor activator of nuclear $factor-{\kappa}B$ ligand (RANKL), the OC differentiation factor. Although the roles of ST5 in cancer and ${\beta}-cells$ have been reported, the function of ST5 in bone cells has not yet been investigated. Knockdown of ST5 by siRNA reduced OC differentiation from primary precursors. Moreover, ST5 downregulation decreased expression of NFATc1, a key transcription factor for osteoclastogenesis. In contrast, overexpression of ST5 resulted in the opposite phenotype of ST5 knockdown. In immunocytochemistry experiments, the ST5 protein is colocalized with Src in RANKL-committed cells. In addition, ST5 enhanced activation of Src and Syk, a Src substrate, in response to RANKL. ST5 reduction caused a decrease in RANKL-evoked calcium oscillation and inhibited translocation of NFATc1 into the nucleus. Taken together, these findings provide the first evidence of ST5 involvement in positive regulation of osteoclastogenesis via Src/Syk/calcium signaling.

Beauvericin, a cyclic peptide, inhibits inflammatory responses in macrophages by inhibiting the NF-κB pathway

  • Yoo, Sulgi;Kim, Mi-Yeon;Cho, Jae Youl
    • The Korean Journal of Physiology and Pharmacology
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    • v.21 no.4
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    • pp.449-456
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    • 2017
  • Beauvericin (BEA), a cyclic hexadepsipeptide produced by the fungus Beauveria bassiana, is known to have anti-cancer, anti-inflammatory, and anti-microbial actions. However, how BEA suppresses macrophage-induced inflammatory responses has not been fully elucidated. In this study, we explored the anti-inflammatory properties of BEA and the underlying molecular mechanisms using lipopolysaccharide (LPS)-treated macrophage-like RAW264.7 cells. Levels of nitric oxide (NO), mRNA levels of transcription factors and the inflammatory genes inducible NO synthase (iNOS) and interleukin (IL)-1, and protein levels of activated intracellular signaling molecules were determined by Griess assay, semi-quantitative reverse transcriptase-polymerase chain reaction (RT-PCR), luciferase reporter gene assay, and immunoblotting analysis. BEA dose-dependently blocked the production of NO in LPS-treated RAW264.7 cells without inducing cell cytotoxicity. BEA also prevented LPS-triggered morphological changes. This compound significantly inhibited nuclear translocation of the $NF-{\kappa}B$ subunits p65 and p50. Luciferase reporter gene assays demonstrated that BEA suppresses MyD88-dependent NF-${\kappa}B$ activation. By analyzing upstream signaling events for $NF-{\kappa}B$ activation and overexpressing Src and Syk, these two enzymes were revealed to be targets of BEA. Together, these results suggest that BEA suppresses $NF-{\kappa}B$-dependent inflammatory responses by suppressing both Src and Syk.

Inhibitory Effect of Penthorun chinense Extract on Allergic Responses in vitro and in vivo (낙지다리 식물 추출물의 알레르기 억제효과)

  • Jo, So young;Kim, Young Mi
    • Journal of Food Hygiene and Safety
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    • v.30 no.4
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    • pp.376-382
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    • 2015
  • Allergic diseases have rapidly increased in recent years. Mast cells play a critical role in IgE-mediated allergy responses and, therefore, closely associated with rhinitis, asthma, and atopic dermatitis. We studied anti-allergic effect of Penthorum chinense extract (PCE) in vitro and in vivo. PCE inhibited the degranulation of mast cells by antigen stimulation and its effect was dose-dependent and reversible in mast cells. PCE also suppressed the production of inflammatory cytokines such as TNF-${\alpha}$ and IL-4 by antigen in mast cells. Mechanistically, PCE inhibited the activation of Syk/LAT pathway which is a key signaling pathway for the activation of mast cells by antigen. Notably, PCE suppressed IgE-mediated allergic responses by antigen in mice. These results strongly suggest that PCE is a potential candidate for anti-allergic treatment.

Salviae Radix Suppresses Mast Cell-mediated Allergic Response: Inhibition of Src-family Kinase (단삼추출물의 Src-family Kinase 억제에 의한 항앨러지 효과)

  • Kim, Young-Mi
    • YAKHAK HOEJI
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    • v.52 no.5
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    • pp.370-375
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    • 2008
  • In this study, the anti-allergic activity and mechanim of Salviae radix (SR) were investigated. The ethanol extract of SR showed significant inhibitory effect on degranulation from antigen-stimulated mast cells and it also inhibited the expression and secretion of TNF-${\alpha}$ and IL-4 in antigen-stimulated RBL-2H3 cells. In the mast cell-mediated local animal allergy model, it suppressed the passive cutaneous anaphylaxis in a dose-dependent manner. As its mechanism of action, SR inhibited the activating phosphorylation of Syk, a downstream signaling molecule of Src-family kinase, for the activation of mast cells. The results of the study indicate that the anti-allergic activity of SR is mediated by the inhibition of Src-family kinase in mast cells.