• Title/Summary/Keyword: downregulation

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Korean Red Ginseng mitigates spinal demyelination in a model of acute multiple sclerosis by downregulating p38 mitogen-activated protein kinase and nuclear factor-κB signaling pathways

  • Lee, Min Jung;Chang, Byung Joon;Oh, Seikwan;Nah, Seung-Yeol;Cho, Ik-Hyun
    • Journal of Ginseng Research
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    • v.42 no.4
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    • pp.436-446
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    • 2018
  • Background: The potential therapeutic values of Korean Red Ginseng extract (KRGE) in autoimmune disorders of nervous system have not been fully investigated. Methods: We used an acute experimental autoimmune encephalomyelitis animal model of multiple sclerosis and determined the effects and mechanism of KRGE on spinal myelination. Results: Pretreatment with KRGE (100 mg/kg, orally) for 10 days before immunization with myelin basic protein $(MBP)_{68-82}$ peptide exerted a protective effect against demyelination in the spinal cord, with inhibited recruitment and activation of immune cells including microglia, decreased mRNA expression of detrimental inflammatory mediators (interleukin-6, interferon-${\gamma}$, and cyclooxygenase-2), but increased mRNA expression of protective inflammatory mediators (insulin-like growth factor ${\beta}1$, transforming growth factor ${\beta}$, and vascular endothelial growth factor-1). These results were associated with significant downregulation of p38 mitogen-activated protein kinase and nuclear factor-${\kappa}B$ signaling pathways in microglia/macrophages, T cells, and astrocytes. Conclusion: Our findings suggest that KRGE alleviates spinal demyelination in acute experimental autoimmune encephalomyelitis through inhibiting the activation of the p38 mitogen-activated protein kinase/nuclear factor-${\kappa}B$ signaling pathway. Therefore, KRGE might be used as a new therapeutic for autoimmune disorders such as multiple sclerosis, although further investigation is needed.

Ginsenoside Rh2 epigenetically regulates cell-mediated immune pathway to inhibit proliferation of MCF-7 breast cancer cells

  • Lee, Hyunkyung;Lee, Seungyeon;Jeong, Dawoon;Kim, Sun Jung
    • Journal of Ginseng Research
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    • v.42 no.4
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    • pp.455-462
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    • 2018
  • Background: Ginsenoside Rh2 has been known to enhance the activity of immune cells, as well as to inhibit the growth of tumor cells. Although the repertoire of genes regulated by Rh2 is well-known in many cancer cells, the epigenetic regulation has yet to be determined, especially for comprehensive approaches to detect methylation changes. Methods: The effect of Rh2 on genome-wide DNA methylation changes in breast cancer cells was examined by treating cultured MCF-7 with Rh2. Pyrosequencing analysis was carried out to measure the methylation level of a global methylation marker, LINE1. Genome-wide methylation analysis was carried out to identify epigenetically regulated genes and to elucidate the most prominent signaling pathway affected by Rh2. Apoptosis and proliferation were monitored to examine the cellular effect of Rh2. Results: LINE1 showed induction of hypomethylation at specific CpGs by 1.6-9.1% (p < 0.05). Genome-wide methylation analysis identified the "cell-mediated immune response"-related pathway as the top network. Cell proliferation of MCF-7 was retarded by Rh2 in a dose-dependent manner. Hypermethylated genes such as CASP1, INSL5, and OR52A1 showed downregulation in the Rh2-treated MCF-7, while hypomethylated genes such as CLINT1, ST3GAL4, and C1orf198 showed upregulation. Notably, a higher survival rate was associated with lower expression of INSL5 and OR52A1 in breast cancer patients, while with higher expression of CLINT1. Conclusion: The results indicate that Rh2 induces epigenetic methylation changes in genes involved in immune response and tumorigenesis, thereby contributing to enhanced immunogenicity and inhibiting the growth of cancer cells.

S Phase Cell Cycle Arrest and Apoptosis is Induced by Eugenol in G361 Human Melanoma Cells

  • Rachoi, Byul-Bo;Shin, Sang-Hun;Kim, Uk-Kyu;Hong, Jin-Woo;Kim, Gyoo-Cheon
    • International Journal of Oral Biology
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    • v.36 no.3
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    • pp.129-134
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    • 2011
  • Eugenol is an essential oil found in cloves and cinnamon that is used widely in perfumes. However, the significant anesthetic and sedative effects of this compound have led to its use also in dental procedures. Recently, it was reported that eugenol induces apoptosis in several cancer cell types but the mechanism underlying this effect has remained unknown. In our current study, we examined whether the cytotoxic effects of eugenol upon human melanoma G361 cells are associated with cell cycle arrest and apoptosis using a range of methods including an XTT assay, Hoechst staining, immunocyto-chemistry, western blotting and flow cytometry. Eugenol treatment was found to decrease the viability of the G361 cells in both a time- and dose-dependent manner. The induction of apoptosis in eugenol-treated G361 cells was confirmed by the appearance of nuclear condensation, the release of both cytochrome c and AIF into the cytosol, the cleavage of PARP and DFF45, and the downregulation of procaspase-3 and -9. With regard to cell cycle arrest, a time-dependent decrease in cyclin A, cyclin D3, cyclin E, cdk2, cdk4, and cdc2 expression was observed in the cells after eugenol treatment. Flow cytometry using a FACScan further demonstrated that eugenol induces a cell cycle arrest at S phase. Our results thus suggest that the inhibition of G361 cell proliferation by eugenol is the result of an apoptotic response and an S phase arrest that is linked to the decreased expression of key cell cycle-related molecules.

Anti-IgE mAb Suppresses Systemic Anaphylaxis through the Inhibitory IgG Receptor Fc ${\gamma}$ RIIb in Mice - Interaction between Anti-IgE and Fc ${\gamma}$ RIIb -

  • Kang, Nam-In;Jin, Zhe-Wu;Lee, Hern-Ku
    • IMMUNE NETWORK
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    • v.7 no.3
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    • pp.141-148
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    • 2007
  • Background: Anti-IgE mAb which binds circulating but not receptor-bound IgE has been shown to be effective in treatment for asthma and other allergic diseases. However, the mechanisms by which anti-IgE mAb influences the pathophysiological responses are remained to be illustrated. This study was undertaken to examine the therapeutic efficacy of non-anaphylactogenic anti-mouse IgE mAb using murine models of IgE-induced systemic fatal anaphylaxis. Methods: Active systemic anaphylaxis was induced by either penicillin V(Pen V) or OVA and passive systemic anaphylaxis was induced by either anaphylactogenic anti-mouse IgE or a mixture of anti-chicken gamma globulin (CGG) IgG1 mAb and CGG. The binding of the Fc portion of anti-IgE to CHO-stable cell line expressing mouse Fc ${\gamma}$ RIIb was examined using flow cytometry. Fc fragments of anti-IgE mAb were prepared using papain digestion. The expression of phosphatases in lungs were assessed by Western blotting and immunohistochemistry. Results: Anti-IgE mAb prevented IgE- and IgG-induced active and passive systemic fatal reactions. In both types of anaphylaxis, anti-IgE mAb suppressed antigen-specific IgE responses, but not those of IgG. Anti-IgE mAb neither prevented anaphylaxis nor suppressed the IgE response in Fc ${\gamma}$ RIIb-deficient mice. The Fc portion of anti-IgE mAb was bound to murine Fc ${\gamma}$ RIIb gene-transfected CHO cells and inhibited systemic anaphylaxis. Anti-IgE mAb blocked the anaphylaxis-induced downregulation of Fc ${\gamma}$ RIIb-associated phosphatases such as src homology 2 domain-containing inositol 5-phosphatase (SHIP) and phosphatase and tensin homologue deleted on chromosome ten (PTEN). Conclusion: Anti-IgE mAb prevented anaphylaxis by delivering nonspecific inhibitory signals through the inhibitory IgG receptor, Fc ${\gamma}$ RIIb, rather than targeting IgE.

Methyl 9-Oxo-(10E,12E)-octadecadienoate Isolated from Fomes fomentarius Attenuates Lipopolysaccharide-Induced Inflammatory Response by Blocking Phosphorylation of STAT3 in Murine Macrophages

  • Choe, Ji-Hyun;Yi, Young-Joo;Lee, Myeong-Seok;Seo, Dong-Won;Yun, Bong-Sik;Lee, Sang-Myeong
    • Mycobiology
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    • v.43 no.3
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    • pp.319-326
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    • 2015
  • Fomes fomentarius is a fungus of the Polyporaceae family and is used in traditional oriental therapies. Although the anti-inflammatory activities of this species have been previously reported, the identity of the bioactive compounds responsible for this activity remains unknown. Here, we investigated whether methyl 9-oxo-(10E,12E)-octadecadienoate (FF-8) purified from F. fomentarius exerts anti-inflammatory activity in murine macrophages stimulated with lipopolysaccharide (LPS). FF-8 suppressed secretion of nitric oxide (NO) and prostaglandin $E_2$ through downregulation of inducible NO synthase and cyclooxygenase-2 expression induced by LPS. In addition, pretreatment of cells with FF-8 led to a reduction in levels of secreted inflammatory cytokines such as tumor necrosis factor-${\alpha}$ and interleukin-6 in macrophages stimulated with LPS. Conversely, FF-8 did not affect nuclear factor ${\kappa}B$, p38, c-Jun NH2-terminal kinase, and extracellular signal-regulated kinase pathways. Instead, FF-8 specifically interfered with signal transducer and activator of transcription 3 (STAT3) phosphorylation induced by LPS. Collectively, this study demonstrated that FF-8 purified from F. fomentarius suppresses inflammatory responses in macrophages stimulated with LPS by inhibiting STAT3 activation. Further studies will be required to elucidate the anti-inflammatory effect of FF-8 in vivo.

Differential Modulation of Lipopolysaccharide-Induced Inflammatory Cytokine Production by and Antioxidant Activity of Fomentariol in RAW264.7 Cells

  • Seo, Dong-Won;Yi, Young-Joo;Lee, Myeong-Seok;Yun, Bong-Sik;Lee, Sang-Myeong
    • Mycobiology
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    • v.43 no.4
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    • pp.450-457
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    • 2015
  • Medicinal mushrooms have been used worldwide to treat cancer and modulate the immune system. Over the last several years, there has been increasing interest in isolating bioactive compounds from medicinal mushrooms and evaluating their health beneficial effects. Fomes fomentarius is used in traditional oriental medicine and is known to possess antioxidant, antiinflammatory, antidiabetic, and antitumor effects. In the present study, we isolated fomentariol from Fomes fomentarius and investigated its anti-inflammatory effect in murine macrophages (RAW264.7 cells) stimulated with lipopolysaccharides. Fomentariol inhibited the production of nitric oxide and intracellular reactive oxygen species triggered by lipopolysaccharides. Interestingly, fomentariol differentially regulated cytokine production triggered by lipopolysaccharides. Fomentariol effectively suppressed the production of interleukin-$1{\beta}$ and interleukin-6 but not tumor necrosis factor-${\alpha}$. The inhibitory effect of fomentariol against nitric oxide, interleukin-$1{\beta}$, and interleukin-6 production was possibly mediated by downregulation of the extracellular signal-regulated kinase signaling pathway. Taken together, our results suggest that fomentariol differentially modulated inflammatory responses triggered by lipopolysaccharides in macrophages and is one of the bioactive compounds that mediate the physiological effects of Fomes fomentarius.

Protective Effect of Gardenia jasminoides Against Carbon Tetrachloride-Induced Acute Hepatotoxicity (사염화탄소 유도 급성 간독성 모델에서 치자의 간 보호 효과)

  • Shin, Jun-Kyu;Kim, Hyo-Yeon;Lee, Sun-Mee
    • YAKHAK HOEJI
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    • v.54 no.1
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    • pp.55-61
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    • 2010
  • Gardenia jasminoides is one of the most widely used herbal preparations for the treatment of liver disorders. This study evaluated the potential beneficial effect of G. jasminoides in a mouse model of carbon tetrachloride ($CCl_4$)-induced liver injury. The mice were treated intraperitoneally with $CCl_4$ (10 ${\mu}l$/kg). They received G. jasminoides (30, 100, 300 mg/kg) 48 h, 24 h and 2 h before and 6 h after administering $CCl_4$. The serum activities of aminotransferase and the hepatic level of malondialdehyde were significantly higher 24 h after the $CCl_4$ treatment, while the concentration of reduced glutathione was lower. These changes were attenuated by G. jasminoides. $CCl_4$ increased the level of circulating tumor necrosis factor-$\alpha$ (TNF-$\alpha$) markedly, which was reduced by G. jasminoides. The levels of hepatic inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) protein expression were markedly higher after the $CCl_4$ treatment. G. jasminoides diminished these alterations. $CCl_4$ increased the level of TNF-$\alpha$, iNOS and COX-2 mRNA expressions, and these increases were attenuated by G. jasminoides. These results suggest that G. jasminoides alleviates $CCl_4$-induced liver injury, and this protection is likely due to the reduced oxidative stress and the downregulation of proinflammatory mediators.

BMP-2-Enhanced Chondrogenesis Involves p38 MAPK-mediated Down-Regulation of Wnt-7a Pathway

  • Jin, Eun-Jung;Lee, Sun-Young;Choi, Young-Ae;Jung, Jae-Chang;Bang, Ok-Sun;Kang, Shin-Sung
    • Molecules and Cells
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    • v.22 no.3
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    • pp.353-359
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    • 2006
  • The bone morphogenetic protein (BMP) family has been implicated in control of cartilage development. Here, we demonstrate that BMP-2 promotes chondrogenesis by activating p38 mitogen-activated protein kinase (MAPK), which in turn downregulates $Wnt-7a/{\beta}$-catenin signaling responsible for proteasomal degradation of Sox9. Exposure of mesenchymal cells to BMP-2 resulted in upregulation of Sox9 protein and a concomitant decrease in the level of ${\beta}$-catenin protein and Wnt-7a signaling. In agreement with this, the interaction of Sox9 with ${\beta}$-catenin was inhibited in the presence of BMP-2. Inhibition of the p38 MAPK pathway using a dominant negative mutant led to sustained Wnt-7a signaling and decreased Sox9 expression, with consequent inhibition of precartilage condensation and chondrogenic differentiation. Moreover, overexpression of ${\beta}$-catenin caused degradation of Sox9 via the ubiquitin/26S proteasome pathway. Our results collectively indicate that the increase in Sox9 protein resulting from downregulation of ${\beta}$-catenin/Wnt-7a signaling is mediated by p38 MAPK during BMP-2 induced chondrogenesis in chick wing bud mesenchymal cells.

PPARα-Target Gene Expression Requires TIS21/BTG2 Gene in Liver of the C57BL/6 Mice under Fasting Condition

  • Hong, Allen Eugene;Ryu, Min Sook;Kim, Seung Jun;Hwang, Seung Yong;Lim, In Kyoung
    • Molecules and Cells
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    • v.41 no.2
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    • pp.140-149
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    • 2018
  • The $TIS21^{/BTG2/PC3}$ gene belongs to the antiproliferative gene (APRO) family and exhibits tumor suppressive activity. However, here we report that TIS21 controls lipid metabolism, rather than cell proliferation, under fasting condition. Using microarray analysis, whole gene expression changes were investigated in liver of TIS21 knockout (TIS21-KO) mice after 20 h fasting and compared with wild type (WT). Peroxisome proliferator-activated receptor alpha ($PPAR{\alpha}$) target gene expression was almost absent in contrast to increased lipid synthesis in the TIS21-KO mice compared to WT mice. Immunohistochemistry with hematoxylin and eosin staining revealed that lipid deposition was focal in the TIS21-KO liver as opposed to the diffuse and homogeneous pattern in the WT liver after 24 h starvation. In addition, cathepsin E expression was over 10 times higher in the TIS21-KO liver than that in the WT, as opposed to the significant reduction of thioltransferase in both adult and fetal livers. At present, we cannot account for the role of cathepsin E. However, downregulation of glutaredoxin 2 thioltransferase expression might affect hypoxic damage in the TIS21-KO liver. We suggest that the $TIS21^{/BTG2}$ gene might be essential to maintain energy metabolism and reducing power in the liver under fasting condition.

MiR-199a/b-5p Inhibits Lymphangiogenesis by Targeting Discoidin Domain Receptor 1 in Corneal Injury

  • Oh, Sooeun;Seo, Minkoo;Choi, Jun-Sub;Joo, Choun-Ki;Lee, Suk Kyeong
    • Molecules and Cells
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    • v.41 no.2
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    • pp.93-102
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    • 2018
  • Discoidin domain receptor 1 (DDR1) is involved in tumorigenesis and angiogenesis. However, its role in lymphangiogenesis has been unknown. Here, we tested whether downregulation of DDR1 expression by miR-199a/b can suppress lymphangiogenesis. We also aimed to identify miRNA target site(s) in the 3' untranslated region (UTR) of DDR1. Transfection with miR-199a/b-5p mimics reduced expression of DDR1 and tube formation in primary human dermal lymphatic endothelial cells, whereas miR-199a/b-5p inhibitors showed the opposite effects. Critically, injection of miR-199a/b-5p mimics suppressed DDR1 expression and lymphangiogenesis in a corneal alkali-burn rat model. The three well-conserved seed matched sites for miR-199a/b-5p in the DDR1 3'-UTR were targeted, and miRNA binding to at least two sites was required for DDR1 inhibition. Our data suggest that DDR1 promotes enhanced lymphangiogenesis during eye injury, and miR-199a/b-5p suppresses this activity by inhibiting DDR1 expression. Thus, this miRNA may be useful for the treatment of lymphangiogenesis-related eye diseases.