• Title/Summary/Keyword: mitogen

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Effect of Quaternary Ammonium Compounds(QACs) on the Immune Response of eel(Anguilla japonica) In vitro (In vitro에서 Quaternary Ammonium Compounds(QACs)이 뱀장어의 면역반응에 미치는 영향)

  • Choi, Min-Soon
    • Journal of fish pathology
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    • v.13 no.2
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    • pp.103-110
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    • 2000
  • The immunostimulatory effects of quaternary ammonium compounds(QACs) were investigated in leucocytes of eel(Anguilla japonica) in vitro. Proliferation of peripheral blood lymphocytes(PBLs) was no significantly affected by QACs, regardless of mitogen(PHA, ConA and LPS) and the concentration of QACs added. QACs heightened the leucocytes function such as respiratory burst activity, phagocytosis and pinocytosis, resulting in significantly increased the bactericidal activity of macrophages. These results suggested that QAC might modulate the immune responses by activation of leucocytes function but not by increment of immunocompetent cell numbers.

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The MAP Kinase Kinase Gene AbSte7 Regulates Multiple Aspects of Alternaria brassicicola Pathogenesis

  • Lu, Kai;Zhang, Min;Yang, Ran;Zhang, Min;Guo, Qinjun;Baek, Kwang-Hyun;Xu, Houjuan
    • The Plant Pathology Journal
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    • v.35 no.2
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    • pp.91-99
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    • 2019
  • Mitogen-activated protein kinase (MAPK) cascades in fungi are ubiquitously conserved signaling pathways that regulate stress responses, vegetative growth, pathogenicity, and many other developmental processes. Previously, we reported that the AbSte7 gene, which encodes a mitogen-activated protein kinase kinase (MAPKK) in Alternaria brassicicola, plays a central role in pathogenicity against host cabbage plants. In this research, we further characterized the role of AbSte7 in the pathogenicity of this fungus using ${\Delta}AbSte7$ mutants. Disruption of the AbSte7 gene of A. brassicicola reduced accumulation of metabolites toxic to the host plant in liquid culture media. The ${\Delta}AbSte7$ mutants could not efficiently detoxify cruciferous phytoalexin brassinin, possibly due to reduced expression of the brassinin hydrolase gene involved in detoxifying brassinin. Disruption of the AbSte7 gene also severely impaired fungal detoxification of reactive oxygen species. AbSte7 gene disruption reduced the enzymatic activity of cell walldegrading enzymes, including cellulase, ${\beta}$-glucosidase, pectin methylesterase, polymethyl-galacturonase, and polygalacturonic acid transeliminase, during host plant infection. Altogether, the data strongly suggest the MAPKK gene AbSte7 plays a pivotal role in A. brassicicola during host infection by regulating multiple steps, and thus increasing pathogenicity and inhibiting host defenses.

Ginsenoside Rg3 suppresses mast cell-mediated allergic inflammation via mitogen-activated protein kinase signaling pathway

  • Kee, Ji-Ye;Hong, Seung-Heon
    • Journal of Ginseng Research
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    • v.43 no.2
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    • pp.282-290
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    • 2019
  • Background: Ginsenoside Rg3 (G-Rg3) is the major bioactive ingredient of Panax ginseng and has many pharmacological effects, including antiadipogenic, antiviral, and anticancer effects. However, the effect of G-Rg3 on mast cell-mediated allergic inflammation has not been investigated. Method: The antiallergic effects of G-Rg3 on allergic inflammation were evaluated using the human and rat mast cell lines HMC-1 and RBL-2H3. Antiallergic effects of G-Rg3 were detected by measuring cyclic adenosine monophosphate (cAMP), detecting calcium influx, and using real-time reverse transcription polymerase chain reaction, enzyme-linked immunosorbent assay, Western blotting, and in vivo experiments. Results: G-Rg3 decreased histamine release from activated mast cells by enhancing cAMP levels and calcium influx. Proinflammatory cytokine production was suppressed by G-Rg3 treatment via regulation of the mitogen-activated protein kinases/nuclear factor-kappa B and receptor-interacting protein kinase 2 (RIP2)/caspase-1 signaling pathway in mast cells. Moreover, G-Rg3 protected mice against the IgE-mediated passive cutaneous anaphylaxis reaction and compound 48/80-induced anaphylactic shock. Conclusion: G-Rg3 may serve as an alternative therapeutic agent for improving allergic inflammatory disorders.

MtMKK5 inhibits nitrogen-fixing nodule development by enhancing defense signaling

  • Hojin Ryu
    • Journal of Plant Biotechnology
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    • v.49 no.4
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    • pp.300-306
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    • 2022
  • The mitogen-activated protein kinase (MAPK) signaling cascade is essential for a wide range of cellular responses in plants, including defense responses, responses to abiotic stress, hormone signaling, and developmental processes. Recent investigations have shown that the stress, ethylene, and MAPK signaling pathways negatively affect the formation of nitrogen-fixing nodules by directly modulating the symbiotic signaling components. However, the molecular mechanisms underlying the defense responses mediated by MAPK signaling in the organogenesis of nitrogen-fixing nodules remain unclear. In the present study, I demonstrate that the Medicago truncatula mitogen-activated protein kinase kinase 5 (MtMKK5)-Medicago truncatula mitogen-activated protein kinase 3/6 (MtMPK3/6) signaling module, expressed specifically in the symbiotic nodules, promotes defense signaling, but not ethylene signaling pathways, thereby inhibiting nodule development in M. truncatula. U0126 treatment resulted in increased cell division in the nodule meristem zone due to the inhibition of MAPK signaling. The phosphorylated TEY motif in the activation domain of MtMPK3/6 was the target domain associated with specific interactions with MtMKK5. I have confirmed the physical interactions between M. truncatula nodule inception (MtNIN) and MtMPK3/6. In the presence of high expression levels of the defense-related genes FRK1 and WRKY29, MtMKK5a overexpression significantly enhanced the defense responses of Arabidopsis against Pseudomonas syringae pv. tomato DC3000 (Pst DC3000). Overall, my data show that the negative regulation of symbiotic nitrogen-fixing nodule organogenesis by defense signaling pathways is mediated by the MtMKK5-MtMPK3/6 module.

Effects of Lupane-Triterpenoids on Mitogen-induced Proliferation of Lymphocytes (Lupane계 Triterpenoid류가 임파구 분열에 미치는 효과)

  • 김영옥;조대현;정혜주;김진호;장승엽;육창수;양기숙;오오진
    • YAKHAK HOEJI
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    • v.43 no.2
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    • pp.208-213
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    • 1999
  • The effects of five lupane-triterpenoids from leaves of two Acanthopanax spp., chiisanogenin, chisanoside and $22{\alpha}-hydroxychiisanogenin$, acakoreoside A and acantrifoside A on the mitogen-induced proliferation were investigated in vitro. T cell proliferation (TCP) to concanavalin A (Con A) and the B cell proliferation (BCP) to lipopolysaccharide (LPS) were increased by chiisanogenin. TCP to Con A was significantly increased by chiisanoside and acankoreoside A, but not affected by chiisanogenin, $22{\alpha}-hydroxychiisanogenin$ and acantrifoside A, BCP to LPS was significantly increased by acankoreoside A and acantrifoside A, and slightly increased by chiisanoside, chiisanogenin and $22{\alpha}-hydroxychiisanogenin$.

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The Effects of Saenghyuldan(shengxiedan) on Bone Marrow Failure (생혈단의 골수부전 치료효과에 대한 실험적 연구)

  • 이연월;손창규;조종관
    • The Journal of Korean Medicine
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    • v.22 no.1
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    • pp.33-45
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    • 2001
  • Objectives: This experimental study was carried out to prove the effect of Saenghyuldan(SHD; shengxiedan) on bone marrow failure induced by cyclophosphamide(CY) and irradiation in mice. Methods: The following were performed; immunopathology, histopathlogical findings of bone marrow and in the smear of myelocyte. hematopoietic cytokine(IL-3, GM-CSF, TPO), hematopoietic stem cell colony assay, humoral immunity(LPS mitogen response), cell-mediated immunity (Con A mitogen response) and nonspecific immunity(macrophage adherence & phagocytosis) in vitro or vivo. Results: SHD showed a protective effect on bone marrow failure induced by cyclophosphamide(CY) and irradiation in mice. SHD increased lymphoproliferative responses to LPS and Con A, and activated macrophage adherence and phagocytosis to SRBC. Conclusions: We expect that SHD can be used to treat bone marrow failure and immune suppression induced by the chemotherapy or radiation.

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The Effects of PSM on Immune Response (버섯다당체로 구성된 PSM의 면역조절에 미치는 영향)

  • 오영선;오민석;손창규;조종관;송태원
    • The Journal of Korean Medicine
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    • v.22 no.1
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    • pp.46-52
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    • 2001
  • Objectives: This experimental study was carried out to evaluate the effects of PSM(polysaccharide of mushroom) on the immune activity. Methods: The following were performed; Immunotoxicity testing for immunopathology, IgO production & LPS mitogen response for humoral immunity, DTH, ConA mitogen response for cell-mediated immunity, and macrophage adherence & phagocytosis for nonspecific immunity in vitro or in vivo. Results: PSM showed a protective effect on cyclophosphamide-induced leukopenia, increased IgG production and lymphoproliferative responses to LPS; inhanced DTH and lymphoproliferative response Con A; and activated macrophage adherence and phagocytosis to SRBC. Conclusions: It is suggested that PSM can be used for cancer patients with immunosuppression and adapted to many other diseases.

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