• IMMUNE NETWORK
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• v.11 no.6
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• pp.424-427
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• 2011

The nucleotide-oligomerization domain (NOD) proteins are members of the NOD-like receptor (NLR) family, which are intracellular and cytoplasmic receptors. We analyzed the role of NODs for cytokine production by macrophages infected with intracellular pathogen M. leprae, the causative agent of leprosy. Production of pro-inflammatory cytokines such as IL-$1{\beta}$ and TNF-${\alpha}$ was inhibited in the presence of cytochalasin D, an agent blocking phagocytosis, suggesting that intracellular signaling was, partially, required for macrophage activation to M. leprae infection. Next, we investigated the role of NOD1 and NOD2 proteins on NF-${\kappa}B$ activation and cytokine expression. Treatment with M. leprae significantly increased NF-${\kappa}B$ activation and expression of TNF-${\alpha}$ and IL-$1{\beta}$ in NOD1- and NOD2-transfected cells. Interestingly, their activation and expression were inhibited by cytochalasin D, suggesting that stimulation of NOD proteins may be associated with the enhancement of cytokine production in host to M. leprae.

• Proceedings of the PSK Conference
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• 2000.10a
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• pp.233.2-233.2
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• 2000

• IMMUNE NETWORK
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• v.21 no.5
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• pp.36.1-36.16
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• 2021

Peroxiredoxins (Prxs) are ubiquitously expressed peroxidases that reduce hydrogen peroxide or alkyl peroxide production in cells. Prxs are released from cells in response to various stress conditions, and they function as damage-associated molecular pattern molecules. However, the secretory mechanism of Prxs and their roles have not been elucidated. Thus, we aimed to determine whether inflammasome activation is a secretory mechanism of Prxs and subsequently identify the effect of the secreted Prxs on activation of the classical complement pathway. Using J774A.1, a murine macrophage cell line, we demonstrated that NLRP3 inflammasome activation induces Prx1, Prx2, Prx5, and Prx6 secretion in a caspase-1 dependent manner. Using HEK293T cells with a transfection system, we revealed that the release of Prx1 and Prx2 relies on gasdermin-D (GSDMD)-mediated secretion. Next, we confirmed the binding of both Prx1 and Prx2 to C1q; however, only Prx2 could induce the C1q-mediated classical complement pathway activation. Collectively, our results suggest that inflammasome activation is a secretory mechanism of Prxs and that GSDMD is a mediator of their secretion. Moreover, secreted Prx1 and Prx2 bind with C1q, but only Prx2 mediates the classical complement pathway activation.

• Archives of Pharmacal Research
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• v.25 no.6
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• pp.954-963
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• 2002

Lectin-conjugated praecoxin A is a compound, which is combined Wheat Germ Agglutinin (WGA) Lectin with praecoxin A and also known to have an anti-tumor activity. In our lab, in order to investigate its immune reaction other than the anti-tumor activity ever known, we examined cytokines such as IL-6 and IL-12 through their mRNA expressions, which are generally secreted by macrophage both in vivo and in vitro. To analyze, we used RT-PCR for total RNAs of macrophages. As a result, we obtained that both in vitro and in vivo, lectin-conjugated praecoxin A showed an interesting increase on IL-6 and IL-12 even though it may be little hard to say the conjugated form is absolutely more effective than that of lectin or praecoxin A alone for immune response activities. Those results suggest that the conjugated form may give an additional opportunity in a future therapeutic use over its immuno activation properties.

• 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.

• Journal of Microbiology
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• v.39 no.3
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• pp.186-194
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• 2001

Scrub typhus, caused by Orientia tsutsugamushi infection, is clinically and histopathologically characterized by local as well as systemic inflammatory reactions, indicating that orientiae induce mechanisms that amplify the inflammatory response. To reveal underlying mechanisms of chemoattraction and activation of responding leukocytes, expression of chemokine and tumor necrosis factor alpha (TNF-$\alpha$) genes in murine peritoneal macrophages after infection with the obligate intracellular bacterium Ο.tsutsugamushi was investigated. The genes that were unregulated included macrophage inflammatory proteins l$\alpha$/$\beta$(MIP-l$\alpha$/$\beta$), MIP-2, monocyte chemoattractant protein 1(MCP-1), RANTES (regulated upon activation, normal T-cell expressed and secreted), gamma-interferon-inducible protein 10(IP-10) and TNF-$\alpha$. Peak expression of these chemokines and TNF-$\alpha$ was observed between 1 and 3 h after infection. These responses returned to or approached baseline preinfection levels 6 h after challenge. Semiquantitative reverse transcription (RT)-PCR analysis revealed dramatic Increases during infection in the steady-state levels of mRNA ceding for the inhibitory subunit of NF-kB (IkB$\alpha$), whose transcription is enhanced by binding of NF-kB within the IkB$\alpha$promoter region. Thus, Ο. tsutsugamushi appears to be a stung inducer of chemokines and TNF-$\alpha$ which may significantly contribute to inflammation and tissue damage observed in scrub typhus by attracting and activating phagocytic leukocytes.

• Biomedical Science Letters
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• v.18 no.4
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• pp.369-376
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• 2012

Platycodon grandiflorum is a medicinal herb that is used to treat pulmonary and respiratory allergic disorders. The objective of this study was to investigate the protective effects of ethyl acetate extract of Platycodon grandiflorum (PGEA) against inflammation and to discern the molecular mechanism of PGEA in lipopolysaccharide (LPS)-induced signal pathways in RAW264.7 macrophage cells. PGEA suppressed the generation of nitric oxide (NO) and the expression of inducible NO synthase induced by LPS in RAW264.7 cells, and inhibited the release of pro-inflammatory cytokines induced by LPS in RAW264.7 cells. Western blot analysis showed that PGEA suppressed LPS-induced phosphorylation of p38 and c-Jun N-terminal kinase (JNK) but not extracellular signal-regulated kinase and $I{\kappa}-B{\alpha}$ degradation. Inactivation of JNK and p38 was effectively alleviated by PGEA, which subsequently affected the activation of c-Jun and c-Fos, which are the essential components of the activator protein-1 (AP-1) transcription complex. Taken together, the results indicate PGEA suppress the activation of p38, JNK, and AP-1, thereby inhibiting the generation of NO and pro-inflammatory cytokines, which affect the regulation of inflammation. PGEA may be useful for the treatment of various inflammatory diseases.

• Journal of Microbiology and Biotechnology
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• v.19 no.6
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• pp.566-572
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• 2009

Lentinus edodes is a well-known edible and medicinal mushroom used in Oriental cultures. Recently, L. edodes has attracted a lot of attention owing to its antifungal activity, antibacterial activity, antiviral activity, hepatoprotective effect, antitumor activities, and immunomodulatory and cytotoxic effects. In this study, the water-soluble crude polysaccharides, CPF and CPB, which were obtained from the fruiting body and culture cell-free broth of L. edodes by hot-water extraction and ethanol precipitation, were fractionated by DEAE cellulose and Sepharose CL-6B column chromatography, resulting in six polysaccharide fractions, CPFN-G-I, CPFN-G-II, CPFN-G-III, CPFA-G, CPBN-G, and CPBA-G Among these fractions, CPFN-G-I, CPBN-G, and CPBA-G were shown to stimulate the functional activation of macrophages including NO production, cytokine expression, and phagocytosis.

• YAKHAK HOEJI
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• v.46 no.2
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• pp.113-119
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• 2002

The composition of monosaccharides of acidic polysaccharide isolated from ethanol-insoluble and water-soluble fractions of red ginseng roots was analysed and its immunological activities were investigated. Red ginseng acidic polysaccharide (RGAP) was composed of glucose (26.1 mole %), arabinose (1.6 mole %), glucuroninc acid (51.8 mol %) and galacturonic acid (5.1 mole %) as determined by gas liquid chromatography. Addition of RGAP increased production of nitric oxide (NO) and tumor necrosis factor (TNF)-$\alpha$ in the rodent macrophage cultures. Peritoneal macrophages from RGAP-treated mice exhibited potent tumoricidal activities toward P815 and WEHI 164 tumor cells. It was also observed that concentrations of NO and TNF-$\alpha$ were high in the culture medium of macrophages from the mice administered with RGAP. Moreover, treatment of RGAP in vivo stimulated tumoricidal activities of natural killer (NK) cells. Treatment with RGAP increased life span of sarcoma 180-bearing mice and decreased tumor weights of B16-tumor-bearing mice. These results suggest that activation of macrophages and NK cells serve to enhance in vivo anticancer activities of RGAP.

• Clinical and Experimental Reproductive Medicine
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• v.30 no.1
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• pp.5-14
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• 2003

Objective: Present study was aimed to verify the effect of granulocyte macrophage-colony stimulating factor (GM-CSF) in the preimplantation development of mouse embryos and the involvement of the mitogen activated protein kiase (MAPK) in the GM-CSF signaling. Methods: Two-cell embryos were cultured for 96 h in the presence or absence of GM-CSF (0, 0.4, 2, 10 ng/ml) and PD98059, a MEK inhibitor (10 ${\mu}M$). Morphological development, cell number per blastocyst, and apoptotic nuclei, were eamined. MAPK activity of embryonic immunoprecipitate by MAPK (ERK1/2) antibody was measured by in vitro phosphorylation of myelin basic protein. Results: At post hCG 122 h the embryonic development among the experimental groups was significantly different (p=0.018). The rate of blastocyst development and cell number per embryo were the highest in 2 ng/ml GM-CSF treatment group. The percent of apoptotic cells of the GM-CSF-treated embryos was the lowest among the group. In blastocysts, GM-CSF treatment transiently increased MAPK activity. PD098059 attenuated the effect of GM-CSF on the morphological development, increase in cell number per blastocyst, down regulation of apoptosis, and upregulation of MAPK activity, suggesting that activation of MAPK cascade possibly mediated the embryotropic effect of GM-CSF. Conclusion: This result suggested that GM-CSF potentiated the development of preimplantation mouse embryos by activation of MAPK.