• Title/Summary/Keyword: $TNF{\alpha}$ signaling

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Interferon-gamma susceptibility of HL-60 cells, mononuclear cells of umbilical cord blood and bone marrow (HL-60 세포주, 제대혈 및 골수 단핵구 세포의 interferon-gamma에 대한 감수성에 관한 연구)

  • Cheong, Hee Jeong;Hong, Dae Sik;Kim, Sook Ja;Cheong, Jae Hwa;Lee, Joo Young;Lee, Nam Su;Park, Sung Kyu;Won, Jong Ho;Park, Hee Sook;Kim, Sung Il
    • IMMUNE NETWORK
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    • v.1 no.3
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    • pp.230-235
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    • 2001
  • Background: Finding of the regulation of various gene expression by cytokine including $IFN-{\gamma}$ in hematopoietic stem cell will light up the understanding of pathogenesis of aplastic anemia in various aspects. To study on aplastic anemia, however, we have to circumvent the difficulty of directly obtaining bone marrow stem cells from the patient. Therefore, we tried to find out a cell can replace the bone marrow stem cells for study on cell signaling pathway and regulation of gene expression by $IFN-{\gamma}$. Materials and Methods: HL-60 cells, of 20 ng/mL of $IFN-{\gamma}$. Total RNA was isolated from the cells and RT-PCR of the indoleamine 2,3-dioxygenase (IDO), $IFN-{\gamma}$, TNF-${\alpha}$, $MIP-1{\alpha}$, and $TGF-{\beta}2$ was carried out for the estimation of the gene expression. Results: $IFN-{\gamma}$ induced IDO gene expression of mononuclear cells from umbilical cord blood showed similar pattern as compared to that of bone marrow. Whether $INF-{\gamma}$ was treated or not, $TNF-{\alpha}$ was expressed in both mononuclear cells from umbilical cord blood and bone marrow. However, HL-60 cells showed different expression patterns. HL-60 cells would express neither IDO nor $TNF-{\alpha}$ even under the culture with 20ng/mL of $IFN-{\gamma}$. Conclusion: Our results showed bone marrow can be replaced with mononuclear cells from umbilical cord blood in the study on the relation between aplastic anemia and $IFN-{\gamma}$ including $IFN-{\gamma}$ cell signaling pathway.

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Lupeol Improves TNF-α Induced Insulin Resistance by Downregulating the Serine Phosphorylation of Insulin Receptor Substrate 1 in 3T3-L1 Adipocytes (3T3-L1 지방세포에서 루페올의 IRS-1의 인산화 조절을 통한 TNF-α 유도 인슐린 저항성 개선 효과)

  • Hyun Ah Lee;Ji Sook Han
    • Journal of Life Science
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    • v.33 no.11
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    • pp.859-867
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    • 2023
  • Lupeol is a type of pentacyclic triterpene that has been reported to have therapeutic effects for treating many diseases; however, its effect on insulin resistance is unclear clear. This study examined the inhibitory effect of lupeol on the serine phosphorylation of insulin receptor substrate-1 in insulin resistance-induced 3T3-L1 adipocytes. 3T3-L1 cells were cultured and treated with tumor necrosis factor-α (TNF-α) for 24 hours to induce insulin resistance. Cells treated with different concentrations of lupeol (15 μM or 30 μM) or 100 nM of rosiglitazone were incubated. Then, lysed cells underwent western blotting. Lupeol exhibited a positive effect on the negative regulator of insulin signaling and inflammation-activated protein kinase caused by TNF-α in adipocytes. Lupeol inhibited the activation of protein tyrosine phosphatase-1B (PTP-1B)-a negative regulator of insulin signaling-and c-Jun N-terminal kinase (JNK); it was also an inhibitor of nuclear factor kappa-B kinase (IKK) and inflammation-activated protein kinases. In addition, Lupeol downregulated serine phosphorylation and upregulated tyrosine phosphorylation in insulin receptor substrate-1. Then, the downregulated phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) pathway was activated, the translocation of glucose transporter type 4 was stimulated to the cell membrane, and intracellular glucose uptake increased in the insulin resistance-induced 3T3-L1 adipocytes. Lupeol may improve TNF-α-induced insulin resistance by downregulating the serine phosphorylation of insulin receptor substrate 1 by inhibiting negative regulators of insulin signaling and inflammation-activated protein kinases in 3T3-L1 adipocytes.

FGF-2 inhibits TNF-α mediated apoptosis through up-regulation of Bcl2-A1 and Bcl-xL in ATDC5 cells

  • Kim, Hey-Ryun;Heo, Youn-Moo;Jeong, Kyoung-Il;Kim, Yong-Min;Jang, Hae-Lan;Lee, Kwang-Yeol;Yeo, Chang-Yeol;Kim, Sung-Hoon;Lee, Hak-Kyo;Kim, Seung-Ryul;Kim, Eung-Gook;Choi, Joong-Kook
    • BMB Reports
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    • v.45 no.5
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    • pp.287-292
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    • 2012
  • FGF-2 is involved in cell survival, proliferation, apoptosis, and angiogenesis in a wide variety of cells. FRGRs, PI3K and MAP kinases are well known mediators of FGF signaling. Despite its known roles during many developmental processes, including osteogenesis, there are few known targets of FGF-2. In the present study, we identified Bcl2-A1 and Bcl-xL as two prominent targets involved in promoting cell survival. Pretreatment of ATDC5 cells with FGF-2 increased cell survival, while siRNAs specific for Bcl2-A1 and Bcl-xL compromised the anti-apoptotic effect of FGF-2, sensitized the cells to apoptosis triggered by TNF-${\alpha}$. Chemical inhibition of FGFR, NFkB, and PI3K activity by PD173074, pyrrolidine dithiocarbamate, and LY294002 respectively abrogated the FGF-2-mediated induction of Bcl2-A1 and Bcl-xL expression. Taken together, our data demonstrate that a subset of Bcl2 family proteins are the targets of FGF-2 signaling that promotes the survival of ATDC5 cells.

Trichostatin A Protects Liver against Septic Injury through Inhibiting Toll-Like Receptor Signaling

  • Kim, So-Jin;Park, Jin-Sook;Lee, Do-Won;Lee, Sun-Mee
    • Biomolecules & Therapeutics
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    • v.24 no.4
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    • pp.387-394
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    • 2016
  • Sepsis, a serious clinical problem, is characterized by a systemic inflammatory response to infection and leads to organ failure. Toll-like receptor (TLR) signaling is intimately implicated in hyper-inflammatory responses and tissue injury during sepsis. Histone deacetylase (HDAC) inhibitors have been reported to exhibit anti-inflammatory properties. The aim of this study was to investigate the hepatoprotective mechanisms of trichostatin A (TSA), a HDAC inhibitor, associated with TLR signaling pathway during sepsis. The anti-inflammatory properties of TSA were assayed in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. Polymicrobial sepsis was induced in mice by cecal ligation and puncture (CLP), a clinically relevant model of sepsis. The mice were intraperitoneally received TSA (1, 2 or 5 mg/kg) 30 min before CLP. The serum and liver samples were collected 6 and 24-h after CLP. TSA inhibited the increased production of tumor necrosis factor (TNF)-${\alpha}$ and interleukin (IL)-6 in LPS-stimulated RAW264.7 cells. TSA improved sepsis-induced mortality, attenuated liver injury and decreased serum TNF-${\alpha}$ and IL-6 levels. CLP increased the levels of TLR4, TLR2 and myeloid differentiation primary response protein 88 (MyD88) protein expression and association of MyD88 with TLR4 and TLR2, which were attenuated by TSA. CLP increased nuclear translocation of nuclear factor kappa B and decreased cytosolic inhibitor of kappa B ($I{\kappa}B$) protein expression, which were attenuated by TSA. Moreover, CLP decreased acetylation of $I{\kappa}B$ kinase (IKK) and increased association of IKK with $I{\kappa}B$ and TSA attenuated these alterations. Our findings suggest that TSA attenuates liver injury by inhibiting TLR-mediated inflammatory response during sepsis.

Hyperglycemia increases the expression levels of sclerostin in a reactive oxygen species- and tumor necrosis factor-alpha-dependent manner

  • Kang, Jiho;Boonanantanasarn, Kanitsak;Baek, Kyunghwa;Woo, Kyung Mi;Ryoo, Hyun-Mo;Baek, Jeong-Hwa;Kim, Gwan-Shik
    • Journal of Periodontal and Implant Science
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    • v.45 no.3
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    • pp.101-110
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    • 2015
  • Purpose: Sclerostin, an inhibitor of Wnt/${\beta}$-catenin signaling, exerts negative effects on bone formation and contributes to periodontitis-induced alveolar bone loss. Recent studies have demonstrated that serum sclerostin levels are increased in diabetic patients and that sclerostin expression in alveolar bone is enhanced in a diabetic periodontitis model. However, the molecular mechanism of how sclerostin expression is enhanced in diabetic patients remains elusive. Therefore, in this study, the effect of hyperglycemia on the expression of sclerostin in osteoblast lineage cells was examined. Methods: C2C12 and MLO-Y4 cells were used in this study. In order to examine the effect of hyperglycemia, the glucose concentration in the culture medium was adjusted to a range of levels between 40 and 100 mM. Gene expression levels were examined by quantitative reverse transcription-polymerase chain reaction and Western blot assays. Top-Flash reporter was used to examine the transcriptional activity of the ${\beta}$-catenin/lymphoid enhanced factor/T-cell factor complex. Tumor necrosis factor-alpha ($TNF{\alpha}$) protein levels were examined with the enzyme-linked immunosorbent assay. The effect of reactive oxygen species on sclerostin expression was examined by treating cells with 1 mM $H_2O_2$ or 20 mM N-acetylcysteine. Results: The high glucose treatment increased the mRNA and protein levels of sclerostin. High glucose suppressed Wnt3a-induced Top-Flash reporter activity and the expression levels of osteoblast marker genes. High glucose increased reactive oxygen species production and $TNF{\alpha}$ expression levels. Treatment of cells with $H_2O_2$ also enhanced the expression levels of $TNF{\alpha}$ and sclerostin. In addition, N-acetylcysteine treatment or knockdown of $TNF{\alpha}$ attenuated high glucose-induced sclerostin expression. Conclusions: These results suggest that hyperglycemia increases sclerostin expression via the enhanced production of reactive oxygen species and $TNF{\alpha}$.

Anti-Inflammatory Effects of Haliotidis Concha (석결명(石決明)의 항염증효과(抗炎症效果))

  • Moon, Soo-Young;Kim, Young-Woo;Kim, Sang-Chan
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.26 no.4
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    • pp.70-80
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    • 2013
  • Objectives : Haliotidis Concha has been used to treat various human diseases such as liver dysfunction and inflammatory disorder. Although it has been shown the effects of Haliotidis Concha on the various diseases, it has almost not been studied about the anti-inflammatory effects of the Haliotidis Concha and its mechanisms. Methods : This research investigated the effects of the Haliotidis Concha ethanol extract (HCE) on the production of nitric oxide (NO) and prostaglandin $E_2$ ($PGE_2$) as well as tumor necrosis factor-alpha (TNF-${\alpha}$). The protein expressions of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) were assayed by immunoblot analyses, and the productions of NO, $PGE_2$ and TNF-${\alpha}$ were assessed by ELISA. Results : Haliotidis Concha decreased the production of NO and $PGE_2$, and inhibited the expression iNOS and COX-2 proteins in a concentration-dependent manner in LPS-treated Raw 264.7 cells. HCE suppressed the ability of LPS to activate the signaling pathways of nuclear factor kappa B (NF-${\kappa}B$) as indicated by HCE inhibited nuclear NF-${\kappa}B$ level and I-${\kappa}B{\alpha}$ phosphorylation. Also, HCE inhibited mitogen-activated protein kinases (MAPKs). Conclusions : HCE repressed the production of LPS-inducible NO, $PGE_2$ and TNF-${\alpha}$, which may be mediated by inhibition of NF-${\kappa}B$ translocation. This study suggest the use for the treatment of acute inflammatory disorders.

IGF-I Exerts an Anti-inflammatory Effect on Skeletal Muscle Cells through Down-regulation of TLR4 Signaling

  • Lee, Won-Jun
    • IMMUNE NETWORK
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    • v.11 no.4
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    • pp.223-226
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    • 2011
  • Although exercise-induced growth factors such as Insulin-like growth factor-I (IGF-I) are known to affect various aspects of physiology in skeletal muscle cells, the molecular mechanism by which IGF-I modulates anti-inflammatory effects in these cells is presently unknown. Here, we showed that IGF-I stimulation suppresses the expression of toll-like receptor 4 (TLR4), a key innate immune receptor. A pharmacological inhibitor study further showed that PI3K/Akt signaling pathway is required for IGF-I-mediated negative regulation of TLR4 expression. Furthermore, IGF-I treatment reduced the expression of various NF-${\kappa}B$-target genes such as TNF-${\alpha}$ and IL-6. Taken together, these findings indicate that the anti-inflammatory effect of exercise may be due, at least in part, to IGF-I-induced suppression of TLR4 and subsequent downregulation of the TLR4-dependent inflammatory signaling pathway.

Anti-inflammatory and antioxidant effects of umbelliferone in chronic alcohol-fed rats

  • Sim, Mi-Ok;Lee, Hae-In;Ham, Ju Ri;Seo, Kwon-Il;Kim, Myung-Joo;Lee, Mi-Kyung
    • Nutrition Research and Practice
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    • v.9 no.4
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    • pp.364-369
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    • 2015
  • BACKGROUND/OBJECTIVES: Inflammation is associated with various types of acute and chronic alcohol liver diseases. In this study, we examined whether umbelliferone (7-hydroxycoumarin, UF) ameliorates chronic alcohol-induced liver damage by modulating inflammatory response and the antioxidant system. METHODS: Rats were fed a Liber-Decarli liquid diet containing 5% alcohol with or without UF (0.05 g/L) for 8 weeks, while normal rats received an isocaloric carbohydrate liquid diet. RESULTS: Chronic alcohol intake significantly increased serum tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) and interleukin 6 levels and decreased interleukin 10 level; however, UF supplementation reversed the cytokines related to liver damage. UF significantly suppressed hepatic lipopolysaccharide binding protein, toll-like receptor 4 (TLR4), nuclear factor kappa B, and TNF-${\alpha}$ gene expression increases in response to chronic alcohol intake. Masson's trichrome staining revealed that UF improved mild hepatic fibrosis caused by alcohol, and UF also significantly increased the mRNA expressions and activities of superoxide dismutase and catalase in liver, and thus, decreased lipid peroxide and mitochondrial hydrogen peroxide levels. CONCLUSIONS: The findings of this study indicate that UF protects against alcohol-induced liver damage by inhibiting the TLR4 signaling pathway and activating the antioxidant system.

Lactobacillus sakei Lipoteichoic Acid Inhibits MMP-1 Induced by UVA in Normal Dermal Fibroblasts of Human

  • You, Ga-Eun;Jung, Bong-Jun;Kim, Hye-Rim;Kim, Han-Geun;Kim, Tae-Rahk;Chung, Dae-Kyun
    • Journal of Microbiology and Biotechnology
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    • v.23 no.10
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    • pp.1357-1364
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    • 2013
  • Human skin is continuously exposed to ultraviolet (UV)-induced photoaging. UVA increases the activity of MMP-1 in dermal fibroblasts through mitogen-activated protein kinase (MAPK), p38, signaling. The irradiation of keratinocytes by UVA results in the secretion of the inflammatory cytokine, tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), and the stimulation of MMP-1 in normal human dermal fibroblasts (NHDFs). Lipoteichoic acid (LTA) is a component of the cell wall of gram-positive Lactobacillus spp. of bacteria. LTA is well known as an anti-inflammation molecule. LTA of the bacterium Lactobacillus plantarum has an anti-photoaging effect, but the potential anti-photoaging effect of the other bacteria has not been examined to date. The current study showed that L. sakei LTA (sLTA) has an immune modulating effect in human monocyte cells. Our object was whether inhibitory effects of sLTA on MMP-1 are caused from reducing the MAPK signal in NHDFs. It inhibits MMP-1 and MAPK signaling induced by UVA in NHDFs. We also confirmed effects of sLTA suppressing TNF-${\alpha}$ inducing MMP-1 in NHDFs.

Acacia Honey Exerts Anti-Inflammatory Activity through Inhibition of NF-κB and MAPK/ATF2 Signaling Pathway in LPS-Stimulated RAW264.7 Cells

  • Kim, Ha Na;Park, Su Bin;Kim, Jeong Dong;Jeong, Hyung Jin;Jeong, Jin Boo
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2018.10a
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    • pp.97-97
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    • 2018
  • Honey used as conventional medicine has various pharmacological properties. In the honey and anti-inflammatory effect, Gelam honey and Manuka honey has been reported to exert anti-inflammatory activity. However, the anti-inflammatory effect and potential mechanisms of acacia honey (AH) are not well understood. In this study, we investigated anti-inflammatory activity and mechanism of action of AH in LPS-stimulated RAW264.7 cells. AH attenuated NO production through inhibition of iNOS expression in LPS-stimulated RAW264.7 cells. AH also decreased the expressions of $IL-1{\beta}$, IL-6 and $TNF-{\alpha}$ as pro-inflammatory cytokines, and MCP-1 expression as a pro-inflammatory chemokine. In the elucidation of the molecular mechanisms, AH decreased LPS-mediated $I{\kappa}B-{\alpha}$ degradation and subsequent nuclear accumulation of p65, which resulted in the inhibition of $NF-{\kappa}B$ activation in RAW264.7 cells. AH dose-dependently suppressed LPS-mediated phosphorylation of ERK1/2 and p38 in RAW264.7 cells. In addition, AH significantly inhibited ATF2 phosphorylation and nuclear accumulation of ATF2 in LPS-stimulated RAW264.7 cells. These results suggest that AH has an anti-inflammatory effect, inhibiting the production of pro-inflammatory mediators such as NO, iNOS, $TNF-{\alpha}$, IL-6, $IL-1{\beta}$ and MCP-1 via interruption of the $NF-{\kappa}B$ and MAPK/ATF2 signaling pathways.

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