• Title/Summary/Keyword: $l{\kappa}B$$\alpha$

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Functional Analysis of Fibroblastic Reticular Cells Derived from Mouse Lymph Node via Bidirectional Crosstalk with T Cells (T세포와 양방향 작용을 통한 마우스 림프절로부터 분리된 fibroblastic reticular cell의 기능적 분석)

  • Park, Sung Hee;Lee, Jong-Hwan
    • Journal of Life Science
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    • v.23 no.10
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    • pp.1199-1208
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    • 2013
  • Fibroblastic reticular cells (FRCs) form the structural backbone of the T zone provide a guidance path for immigrating T cells in the lymph node (LN). FRCs may contribute directly to developing T-cell biology in the LN and allow analyses of fundamental aspects of FRC biology related to T cells. FRCs inhibited T-cell apoptosis, and FRC culture supernatants strongly induced the expression of Bcl-xL in T cells against doxorubicin. Coculture of FRC and T cells resulted in rearrangements of the actin cytoskeleton, as well as global changes in the morphology of the FRCs. In addition, when cocultured, the T cells adhered to the FRC monolayer, and the membrane intercellular adhesion molecule (ICAM)-1 was slightly increased by day-dependent manner. In contrast, the expression of soluble ICAM-1 was dramatically increased in a day-dependent manner. Several chemokines, such as CCL5, CXCL1, CXCL5, CXCL16, CCL8, CXCL13, and ICAM-1, and MMPs were expressed in FRCs sensed by tumor necrosis factor (TNF) families. Nuclear factor kappa B ($NF{\kappa}B$)-RelA of the $NF{\kappa}B$ canonical pathway was translocated into FRC nuclear by $TNF{\alpha}$. In contrast, p52 proteolyzed from p100, a counterpart of RelB of the noncanonical $NF{\kappa}B$ pathway, accumulated in the peripheral FRC nucleus by agonistic anti-$LT{\beta}R$ antibody. In summary, we propose a model in which FRCs engage in bidirectional crosstalk to increase the efficiency of T-cell biology. This cooperative feedback loop may help to maintain tissue integrity and function during immune responses.

A comparative study of the immuno-modulatory activities of ethanol extracts and crude polysaccharide fractions from Annona muricata L. (가시여지잎(Annona muricata L.) 에탄올 추출물과 조다당 분획분의 면역활성 비교)

  • Kim, Yi-Eun;Lee, Joeng-Hee;Sung, Nak-Yun;Ahn, Dong-Hyun;Byun, Eui-Hong
    • Korean Journal of Food Science and Technology
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    • v.49 no.4
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    • pp.453-458
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    • 2017
  • This study compared the immuno-modulatory effects of ethanol extracts (A. muricata L. ethanol extracts, ALE) and crude polysaccharide fraction (A. muricata L. crude polysaccharide fraction, ALP) from Annona muricata L. in macrophages. Immuno-modulatory activity was determined by assessing cell viability, nitric oxide (NO) production, inducible NO synthase (iNOS) expression and cytokine production in RAW 264.7 a macrophage cell line. Both ALE and ALP treatment did not affect cytotoxicity, and ALP treatment significantly increased NO production. Additionally, cytokine production [tumor necrosis factor ($TNF-{\alpha}$; $2909.04{\pm}4.1pg/mL$), interleukin (IL)-6; $662.84{\pm}5.3pg/mL$, and $IL-1{\beta}$; $852.37{\pm}2.2pg/mL$), was highly increased in the ALP ($250{\mu}g/mL$) treated group compared to the ALE ($250{\mu}g/mL$) treated group ($TNF-{\alpha}$; $1564.50{\pm}6.1pg/mL$, IL-6; $517.24{\pm}4.1pg/mL$ and $IL-1{\beta}$; $237.23{\pm}1.8pg/mL$). Moreover, ALP treatment considerably increased the expression of mitogen-activated protein kinase (MAPKs) and nuclear $factor-{\kappa}B$ ($NF-{\kappa}B$) in the macrophages. Therefore, ALP can induce macrophage activation through MAPK and $NF-{\kappa}B$ signaling and this can be a potential candidate for development of nutraceuticals.

L1 Cell Adhesion Molecule Suppresses Macrophage-mediated Inflammatory Responses (L1 Cell Adhesion Molecule에 의한 대식세포 매개 염증반응의 억제 기전 분석)

  • Yi, Young-Su
    • YAKHAK HOEJI
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    • v.60 no.3
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    • pp.128-134
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    • 2016
  • L1 cell adhesion molecule (L1CAM) is a cell surface molecule to initiate a variety of cellular responses through interacting with other cell adhesion molecules in a homophilic or heterophilic manner. Although its expression was found to be upregulated in some tumor cells, including cholangiocarcinomas, and ovarian cancers, and many studies have investigated the role of L1CAM in these cancers, its role in inflammatory responses has been poorly understood. In this study, we explored the role of L1CAM in macrophage-mediated inflammatory responses. L1CAM significantly suppressed the production of nitric oxide (NO), but induced cell proliferation in RAW264.7 cells. L1CAM expression was detectable, but its expression was markedly decreased by lipopolysaccharide (LPS) in RAW264.7 cells. In addition, the expression of pro-inflammatory genes, such as tumor necrosis factor (TNF)-${\alpha}$, cyclooxygenase (COX)-2, and inducible nitric oxide synthase (iNOS) induced by LPS was dramatically suppressed by L1CAM in RAW264.7 cells. L1CAM inhibited the transcriptional activities of NF-${\kappa}B$ and AP-1 while its cytoplasmic domain deletion form, $L1{\Delta}CD$ did not suppressed their activities in RAW264.7 cells. Moreover, L1CAM suppressed nuclear translocation of p65 and p50 as well as c-Jun, c-Fos and p-ATF2 which are transcription factors of NF-${\kappa}B$ and AP-1, respectively. In conclusion, L1CAM suppressed inflammatory responses in macrophages through inhibiting NF-${\kappa}B$ and AP-1 pathways.

Anti-Inflammatory Effect of Hot Water Extract of Aronia Fruits in LPS-Stimulated RAW 264.7 Macrophages (LPS 자극 RAW 264.7 대식세포에 있어서 아로니아 열매 열수 추출물의 항염증 효과)

  • Yang, Hui;Oh, Kwang-Hoon;Yoo, Yung Choon
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.44 no.1
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    • pp.7-13
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    • 2015
  • In this study, anti-inflammatory activity of hot water extract of Aronia fruits (AF-H) was examined. Pre-treatment with AF-H significantly inhibited production of nitric oxide (NO) and prostaglandin E-2 in a dose-dependent manner in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. The inhibitory effect of AF-H on LPS-induced inflammation was also confirmed by down-regulation of inducible NO synthase as well as cyclooxygenase-2 protein expression. Furthermore, treatment with AF-H significantly inhibited secretion of inflammatory cytokines such as tumor-necrosis $factor-{\alpha}$ and interleukin-6. Signal transduction pathway studies further indicated that AF-H inhibited LPS-induced activation of nuclear $factor-{\kappa}B$, but not mitogen-activated protein kinase. Treatment with AF-H also partially protected against LPS-induced lethal shock in C57BL/6 mice, although its effect was not statistically significant. These results suggest that AF-H is a more promising nutraceutical or medicinal agent for inhibition of LPS-induced inflammation or inflammation-related diseases.

Potential Role of Ursodeoxycholic Acid in Suppression of Nuclear Factor Kappa B in Microglial Cell Line (BV-2)

  • Joo, Seong-Soo;Won, Tae-Joan;Lee, Do-Ik
    • Archives of Pharmacal Research
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    • v.27 no.9
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    • pp.954-960
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    • 2004
  • Expression of the NF-$textsc{k}$B-dependent genes responsible for inflammation, such as TNF-$\alpha$, IL-1$\beta$, and nitric oxide synthase (NOS), contributes to chronic inflammation which is a major cause of neurodegenerative diseases (i.e. Alzheimer's disease). Although NF-$textsc{k}$B plays a biphasic role in different cells like neurons and microglia, controlling the activation of NF-$textsc{k}$B is important for its negative feedback in either activation or inactivation. In this study, we found that ursodeoxycholic acid (UDCA) inhibited I$textsc{k}$B$\alpha$ degradation to block expression of the NF-$textsc{k}$B-dependent genes in microglia when activated by $\beta$-amyloid peptide (A$\beta$). We also showed that when microglia is activated by $A\beta$42, the expression of A20 is suppressed. These findings place A20 in the category of ' protective ' genes, protecting cells from pro-inflammatory reper-toires induced in response to inflammatory stimuli in activated microglia via NF-$textsc{k}$B activation. In light of the gene and proteins for NF-$textsc{k}$B-dependent gene and inactivator for NF-$textsc{k}$B (I$textsc{k}$B$\alpha$), the observations now reported suggest that UDCA plays a role in supporting the attenuation of the production of pro-inflammatory cytokines and NO via inactivation of NF-$textsc{k}$B. Moreover, an NF-$textsc{k}$B inhibitor such as A20 can collaborate and at least enhance the anti-inflammatory effect in microglia, thus giving a potent benefit for the treatment of neurodegenerative diseases such as AD.uch as AD.

Anti-Inflammatory Effect of Ethyl Acetate Fraction Isolated from Undaria pinnatifida on Lipopolysaccharides-Stimulated RAW 264.7 Cells (LPS로 유도된 RAW 264.7 대식세포에 대한 미역(Undaria pinnatifida) Ethyl Acetate 분획물의 항염증 효과)

  • Choi, Min-Woo;Kim, Jae-Il
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.46 no.4
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    • pp.384-392
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    • 2013
  • An ethanolic extract of Undaria pinnatifida was fractionated using several solvents. Of the fractions, the ethyl acetate fraction had the greatest inhibitory effect on lipopolysaccharide (LPS)-induced nitric oxide (NO) production in RAW 264.7 macrophage cells. Using this fraction (U. pinnatifida ethyl acetate extract, UPE), we investigated the molecular mechanism underlying its inhibitory effect on LPS-stimulated RAW 264.7 cells. Pretreatment of the cells with up to $100{\mu}g/mL$ UPE significantly inhibited NO production and inducible nitric oxide synthase (iNOS) expression, in a dose-dependent manner. Similarly, UPE treatment markedly reduced the production of pro-inflammatory cytokines, such as interleukin (IL)-1, IL-6 and tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), while it strongly suppressed the nuclear translocation of nuclear factor-kappa B (NF-${\kappa}B$) by preventing proteolytic degradation of inhibitor of nuclear factor ${\kappa}B$ $(I{\kappa}B)-{\alpha}$. Moreover, UPE treatment significantly reduced the phosphorylation of phosphatidylinositol 3-kinase (PI3K)/Akt and mitogen-activated protein kinase (MAPK) in LPS-stimulated cells. These results indicate that UPE contains anti-inflammatory compounds and suggest that it might be used as a functional food material that assists in prevention of inflammatory diseases.

A NOTE ON PARTIAL SIGN-SOLVABILITY

  • Hwang, Suk-Geun;Park, Jin-Woo
    • Bulletin of the Korean Mathematical Society
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    • v.43 no.3
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    • pp.471-478
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    • 2006
  • In this paper we prove that if AX=b is a partial sign-solvable linear system with A being sign non-singular matrix and if ${\alpha}=\{j:\;x_j\;is\;sign-determined\;by\; Ax=b\}, then $A_{\alpha}X_{\alpha}=b_{\alpha}$ is a sign-solvable linear system, where $A_{\alpha}$ denotes the submatrix of A occupying rows and columns in o and xo and be are subvectors of x and b whose components lie in ${\alpha}$. For a sign non-singular matrix A, let $A_l,\;...,A_{\kappa}$ be the fully indecomposable components of A and let ${\alpha}_i$ denote the set of row numbers of $A_r,\;r=1,\;...,\;k$. We also show that if $A_x=b$ is a partial sign-solvable linear system, then, for $r=1,\;...,\;k$, if one of the components of xor is a fixed zero solution of Ax=b, then so are all the components of x_{{\alpha}r}$.

Ethanol extract of Callophyllis japonica enhances nitric oxide and tumor necrosis factor-alpha production in mouse macrophage cell line, RAW 264.7 cells

  • Ahn, Mee-Jung;Park, Dal-Soo;Yang, Won-Hyung;Go, Gyung-Min;Kim, Hyung-Min;Hyun, Jin-Won;Park, Jae-Woo;Shin, Taek-Yun
    • Advances in Traditional Medicine
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    • v.7 no.4
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    • pp.341-347
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    • 2007
  • Red seaweed (Callophyllis japonica) has long formed part of the diet of Asians, but the pharmacological properties of this plant have not been evaluated. In this study, we examined the effect of an ethanol extract of C. japonica on the generation of nitric oxide (NO) in RAW 264.7 cells. The C. japonica extract increased the generation of NO and tumor necrosis $factor-{\alpha}$ ($TNF-{\alpha}$), which were detected by the Griess method and an enzyme-linked immunosorbent assay, respectively. The increased production of NO by C. japonica extract was inhibited by $N^G$-monomethyl-L-arginine ($100{\mu}M$), a specific inhibitor of NO production in the L-arginine-dependent pathway, and by the nuclear $factor-{\kappa}B$ ($NF-{\kappa}B$) inhibitor, pyrrolidine dithiocarbamate ($10-100{\mu}M$) in a dose-dependent manner. These findings demonstrate that C. japonica extract stimulates the production of NO and $TNF-{\alpha}$ in RAW 264.7 cells through the activation of $NF-{\kappa}B$ and that this extract might also inhibit the growth of the human leukemic cells.

Anti-inflammatory Effect of Perilla frutescens (L.) Britton var. frutescens Extract in LPS-stimulated RAW 264.7 Macrophages

  • Lee, Hyun-Ah;Han, Ji-Sook
    • Preventive Nutrition and Food Science
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    • v.17 no.2
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    • pp.109-115
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    • 2012
  • This study was designed to investigate the inhibitory effects of Perilla frutescens (L.) Britton var. frutescens extract on the production of inflammation-related mediators (NO, ROS, NF-${\kappa}B$, iNOS and COX-2) and pro-inflammatory cytokines (TNF-${\alpha}$, IL-$1{\beta}$, IL-6) in lipopolysaccharide-stimulated RAW 264.7 macrophages. Perilla frutescents (L.) Britton var. frutescens was air-dried and extracted with ethanol. The extract dose-dependently decreased the generation of intracellular reactive oxygen species and dose-dependently increased antioxidant enzyme activities, such as superoxide dismutase, catalase and glutathione peroxidase in lipopolysaccharide stimulated RAW 264.7 macrophages. Also, Perilla frutescens (L.) Britton var. frutescens extract suppressed NO production in lipopolysaccharide-stimulated RAW 264.7 cells. The expressions of pro-inflammatory cytokines (TNF-${\alpha}$, IL-$1{\beta}$ and IL-6), NF-${\kappa}B$, iNOS and COX-2 were inhibited by the treatment with the extract. Thus, this study shows the Perilla frutescens (L.) Britton var. frutescens extract could be useful for inhibition of the inflammatory process.

A Methanol Extract of Adansonia digitata L. Leaves Inhibits Pro-Inflammatory iNOS Possibly via the Inhibition of NF-κB Activation

  • Ayele, Yihunie;Kim, Jung-Ah;Park, Eunhee;Kim, Ye-Jung;Retta, Negussie;Dessie, Gulelat;Rhee, Sang-Ki;Koh, Kwangoh;Nam, Kung-Woo;Kim, Hee Seon
    • Biomolecules & Therapeutics
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    • v.21 no.2
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    • pp.146-152
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    • 2013
  • This study examined the total polyphenol content of eight wild edible plants from Ethiopia and their effect on NO production in Raw264.7 cells. Owing to its relatively high polyphenol concentration and inhibition of NO production, the methanol extract of Adansonia digitata L. leaf (MEAD) was subjected to detailed evaluation of its antioxidant and anti-inflammatory effects. Antioxidant effects were assessed by measuring free-radical-scavenging activity using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and oxygen-radical-absorbance capacity (ORAC) assays, while anti-inflammatory effects were assessed by measuring inducible nitric oxide synthase (iNOS) expression in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. In the ORAC assay, MEAD was 10.2 times more potent than vitamin C at eliminating peroxyl radicals. In DPPH assay, MEAD also showed a strong ROS scavenging effect. MEAD significantly inhibited iNOS activity ($IC_{50}=28.6{\mu}g/ml$) of LPS-stimulated Raw264.7 cells. We also investigated the relationship between iNOS expression and nuclear factor kappa B (NF-${\kappa}B$) activation. MEAD inhibited $I{\kappa}B{\alpha}$ degradation and NF-${\kappa}B$ translocation from the cytosol to the nucleus in LPS-induced RAW264.7 cells without significant cytotoxic effects, as confirmed by MTT assay. These results suggest that MEAD inhibits anti-inflammatory iNOS expression, which might be related to the elimination of peroxyl radicals and thus the inhibition of $I{\kappa}B{\alpha}$-mediated NF-${\kappa}B$ signal transduction.