• Journal of Oral Medicine and Pain
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• v.24 no.4
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• pp.361-374
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• 1999

F. nucleatum is a gram-negative obligate anaerobe which is the principal and most frequent cause of gingival inflammation and is the predominant pathogen isolated in subsequent periodontal breakdown. It is also one of the most numerous bacteria found in subgingival plaque samples from healthy sites; its numbers are about 10-fold greater in plaque from periodontally diseased sites. The purpose of this study is to examine the effects of outer membrane(OM), outer membrane vesicle(OMV), and lipopolysaccharide(LPS) from F. nucleatum ATCC 25586 strain on the growth of human gingival fibroblasts and HOS 941 cells, and on the $TNF-{\alpha}$ production / $TNF-{\alpha}$ mRNA expression of mouse splenocytes. For the examination of cytotoxic effects, $TNF-{\alpha}$ production and $TNF-{\alpha}$ mRNA expression, the MTT assay, the ELISA and the RT-PCR were performed, respectively. All extracts of F. nucleatum tested were cytotoxic to both of human gingival fibroblasts and HOS 941 cells, and the significant difference of cytotoxic activity among the extracts was not observed. In the effects of these extracts on the $TNF-{\alpha}$ production / $TNF-{\alpha}$ mRNA expression of mouse splenocytes, all extracts of F. nucleatum tested also stimulated the $TNF-{\alpha}$ production / $TNF-{\alpha}$ mRNA expression, but the effects of the OM extracts on the $TNF-{\alpha}$ production / $TNF-{\alpha}$ mRNA expression were higher than those of the OMV and the LPS extracts. The pattern of the $TNF-{\alpha}$ mRNA expression was similar to that of the $TNF-{\alpha}$ production. These results indicate that F. nucleatum seems to contribute to the pathogenesis of periodontal diseases at least by its cytotoxicity, directly and its $TNF-{\alpha}$ production, indirectly.

• Journal of Life Science
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• v.29 no.11
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• pp.1251-1257
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• 2019

Peptidoglycan (PG) is found in atheromatous lesions of arteries, where monocytes/macrophages express inflammatory cytokines, including tumor necrosis factor-alpha ($TNF-{\alpha}$). This study investigated the effects of PG on $TNF-{\alpha}$ expression and examined possible cellular factors involved in $TNF-{\alpha}$ upregulation. The overall aim was to identify the molecular mechanisms underlying inflammatory responses to bacterial pathogen-associated molecular patterns in the artery. Exposure of human THP-1 monocytic cells to PG enhanced the secretion of $TNF-{\alpha}$ and induced its gene transcription. Inhibition of TLR-2/4 with OxPAPC significantly inhibited $TNF-{\alpha}$ gene expression, whereas inhibition of LPS by polymyxin B did not. The PG-induced expression of $TNF-{\alpha}$ was also significantly suppressed by pharmacological inhibitors that modulate activities of cellular signaling molecules; for example, U0126 (an ERK inhibitor), SB202190 (a p38 MAPK inhibitor), and SP6001250 (a JNK inhibitor) significantly attenuated PG-induced transcription of $TNF-{\alpha}$ and secretion of its gene product. $TNF-{\alpha}$ expression was also inhibited by rapamycin (an mTOR inhibitor), LY294002 (a PI3K inhibitor), and Akt inhibitor IV (an Akt inhibitor). ROS-regulating compounds, like NAC and DPI, also significantly attenuated $TNF{\alpha}$ expression induced by PG. These results suggest that PG induces $TNF-{\alpha}$ expression in monocytes/macrophages by multiple molecules, including TLR-2, PI3K, Akt, mTOR, MAPKs, and ROS.

• Biomedical Science Letters
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• v.24 no.3
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• pp.213-220
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• 2018

Triglyceride (TG) is known to be associated with inflammatory disease including atherosclerosis. In a variety of atherosclerosis models, T lymphocytes are localized in the earliest lesions of atherosclerosis. T cell associated cytokines such as $TNF-{\alpha}$ and $IFN-{\gamma}$ have pre-dominant inflammatory effects in chronic vascular diseases. In our previous study, we found that the expression of $TNF-{\alpha}$ and its receptor, $TNF-{\alpha}R$ was increased when Jurkat T lymphocyte cell lines were exposed to TGs. Therefore, experiments were conducted to determine which cell signaling pathway are involved in the increase of $TNF-{\alpha}$ and $TNF-{\alpha}R$ expression by TGs. To identify signal transduction pathways involved in TG-induced upregulation of $TNF-{\alpha}$, we treated TG-exposed Jurkat T cells with specific inhibitors for MEK1, PI3K, $NF-{\kappa}B$ and PKC. We found that inhibition of the MEK1 pathway blocked TG-induced upregulation of $TNF-{\alpha}$. However, the expression level of $TNF-{\alpha}R$ did not change with any signal transduction inhibitor. Based on this observation, we suggest that increase of exogenous TG induces increase of $TNF-{\alpha}$ expression through MEK1 pathway in Jurkat T cells. In addition, it was confirmed that the increase of $TNF-{\alpha}$ and $TNF-{\alpha}R$ expression by TGs occurs via different pathways.

• Korean Journal of Plant Resources
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• v.22 no.6
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• pp.552-557
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• 2009

Allicin, a garlic componente, is believed to provide protection against various diseases including inflammation. Since interactions of the cell adhesion molecules are known to play important roles in mediating inflammation, inhibiting adhesion protein upregulation is a possible therapeutic target. In this study, we demonstrate that TNF-${\alpha}$- and catalase-induced expression of ICAM-1 on human lung epithelial cells (A549) in a dose-dependent manner and catalase expression and activity were also increased in TNF-${\alpha}$-treated cells. Treatment of the TNF-${\alpha}$-treated cells with catalase inhibitor 3-amino-1,2,4-triazole resulted in a significant decreased the level of ICAM-1. These data suggest that induction of ICAM-1 expression by TNF-${\alpha}$ is associated with catalase. In addition, allicin was found to inhibit the TNF-${\alpha}$ induced expression of ICAM-1 on the A549 cells. This compound also inhibited the production of catalase induced by TNF-${\alpha}$, which suggests that the inhibition of ICAM-1 expression by allicin may be due to the modulated production of catalase.

• Journal of the Korean Society of Radiology
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• v.13 no.1
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• pp.133-140
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• 2019

Triglycerides (TG) are one of the triggers of chronic inflammatory lesions in the blood vessels. In the key factors in the development of inflammatory diseases, Pro-inflammatory cytokines such as tumor necrosis factor-alpha $(TNF-){\alpha}$ and interleukin-1 beta ($IL-1{\beta}$) contribute to the development of inflammatory lesions by recruiting other immune cells in the inflamed area or causing cell necrotic death. In this study, I investigated the effect of Jurkat T lymphocytes and U937 monocytes involved in vascular inflammation development on the expression of $TNF-{\alpha}$ and $IL-1{\beta}$ on exposure to TGs. In Jurkat cells, mRNA expression of $TNF-{\alpha}$ is increased by exposure to TGs. However, the expression levels of $TNF-{\alpha}$ and $IL-1{\beta}$ were increased by TGs in U937 cells. To investigate whether inducible nitric oxide synthase (iNOS) is involved in the increase of expression of $TNF-{\alpha}$ and $IL-1{\beta}$ by TGs, treatment of W1400 (an iNOS inhibitor) resulted in recovery of expression level both $TNF-{\alpha}$ and $IL-1{\beta}$. Based on the present study, it was confirmed that the expression of $TNF-{\alpha}$ and $IL-1{\beta}$ in monocytes and T lymphocytes. This increased cytokines contribute to development of vascular inflammatory lesions. In addition, iNOS is involved in the increase of $TNF-{\alpha}$ and $IL-1{\beta}$ expression by TGs.

• Korean Journal of Microbiology
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• v.51 no.3
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• pp.308-311
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• 2015

Chungkookjang (fermented soybeans) contains diverse peptides. Human breast cancer MDA-MB-231 cells were treated with peptide H derived from Chungkookjang, and $TNF{\alpha}$ expression in the cells was conspicuously repressed, suggesting peptide H's regulation of IL6 since IL6 is induced by $TNF{\alpha}$. The structure of peptide H was different from those of glucocorticoid and dexamethasone, suggesting different mechanisms of $TNF{\alpha}$ expression suppression. Peptide H which reduces $TNF{\alpha}$ expression can be developed as drugs for cancer, rheumatoid arthritis and Crohn's disease, after more investigation.

• YAKHAK HOEJI
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• v.52 no.1
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• pp.37-42
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• 2008

Betulinic acid, a naturally occurring pentacyclic triterpenoid, is found in abundance in the outer bark of white birch (Betula alba). In this study, we investigated if betulinic acid affects cytokine expression from activated macrophage cells. ELISA result showed that stimulation of HL-60 cells with proinflammatory cytokine such as $TNF-{\alpha}$ resulted in MCP-1 release into culture medium. In addition, transcriptional upregulation of MCP-1 in response to $TNF-{\alpha}$ was observed by RT-PCR analysis. However, incubation of HL-60 cells with betulinic acid prior to $TNF-{\alpha}$ treatment abrogated MCP-1 expression in transcription and translational level. Consistent with a number of studies which reported requirement of ERK activation for $TNF-{\alpha}$ expression, Western blot analysis showed that $TNF-{\alpha}-induced$ ERK activation was suppressed by pretreatment of HL-60 cells with betulinic acid. Taken together, our data indicate that betulinic acid exerts its anti-inflammatory effect through inhibition of $TNF-{\alpha}-induced$ ERK activation which is required for the subsequent MCP-1 release.

• The Korean Journal of Physiology and Pharmacology
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• v.20 no.4
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• pp.347-355
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• 2016

Cryptotanshinone (CPT) is a natural compound isolated from traditional Chinese medicine Salvia miltiorrhiza Bunge. In the present study, the regulatory effect and potential mechanisms of CPT on tumor necrosis factor alpha ($TNF-{\alpha}$) induced lectin-like receptor for oxidized low density lipoprotein (LOX-1) were investigated. Human umbilical vein endothelial cells (HUVECs) were cultured and the effect of $TNF-{\alpha}$ on LOX-1 expression at mRNA and protein levels was determined by Real-time PCR and Western blotting respectively. The formation of intracellular ROS was determined with fluorescence probe $CM-DCFH_2-DA$. The endothelial ox-LDL uptake was evaluated with DiI-ox-LDL. The effect of CPT on LOX-1 expression was also evaluated with SD rats. $TNF-{\alpha}$ induced LOX-1 expression in a dose- and time- dependent manner in endothelial cells. $TNF-{\alpha}$ induced ROS formation, phosphorylation of $NF-{\kappa}B$ p65 and ERK, and LOX-1 expression, which were suppressed by rotenone, DPI, NAC, and CPT. $NF-{\kappa}B$ inhibitor BAY11-7082 and ERK inhibitor PD98059 inhibited $TNF-{\alpha}-induced$ LOX-1 expression. CPT and NAC suppressed $TNF-{\alpha}-induced$ LOX-1 expression and phosphorylation of $NF-{\kappa}B$ p65 and ERK in rat aorta. These data suggested that $TNF-{\alpha}$ induced LOX-1 expression via ROS activated $NF-{\kappa}B/ERK$ pathway, which could be inhibited by CPT. This study provides new insights for the anti-atherosclerotic effect of CPT.

• Archives of Pharmacal Research
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• v.27 no.10
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• pp.1073-1079
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• 2004

Interactions of the cell adhesion molecules are known to play important roles in mediating inflammation. The proinflammatory cytokine, tumor necrosis factor-${\alpha}$(TNF-${\alpha}$), activates the NF-kB signaling pathway, which induces the expression of various genes, such as intercellular adhesion molecule-1 (ICAM-1). In this study, the effect of vitamin C on the ICAM-1 expression induced by TNF-${\alpha}$ in a human neuroblastoma cell line, SK-N-SH was investigated. Treatment with vitamin C resulted in the downregulation of the TNF-${\alpha}$-induced surface expression and ICAM-1 mRNA levels in a concentration-dependent manner. Moreover, a gel shift analysis indicated that vitamin C dose-dependently inhibited the NF-kB activation and IkB${\alpha}$ degradation induced by TNF-${\alpha}$. Taken together, these results suggest that vitamin C downregulates TNF-${\alpha}$- induced ICAM-1 expression via the inhibition of NF-kB activation.

• Archives of Pharmacal Research
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• v.28 no.11
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• pp.1257-1262
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• 2005

MMP-9 is a metalloproteinase capable of basement membrane degradation in vivo. Expression of MMP-9 can be found in normal conditions such as trophoblasts, osteoclasts, and leukocytes and their precursors. They also occur as well as in pathological conditions, such as the invasive growth of primary tumors, metastasis, angiogenesis, rheumatoid arthritis, and periodontal diseases. MMP-9 upregulation can be highly induced by a wide range of agents. These agents include growth factors, cytokines, cell-cell, and cell-ECM adhesion molecules, and agents altering cell shape. Here, we observed that TNF-$\alpha$ stimulated human monocytic cell line, HL-60 produced MMP-9 in a dose and time dependent manner. Real time PCR results indicated transcriptional upregulation of MMP-9 as early as 3 h post TNF-$\alpha$ stimulation. To investigate the signaling pathway underlined in TNF-$\alpha$ induced MMP-9 expression, three MAP kinase inhibitors were added to cells 1 h prior to TNF-$\alpha$ treatment. The ERK inhibitor completely abolished MMP-9 expression by TNF-$\alpha$. But neither p38 MAP kinase nor JNK inhibitor had an effect on TNF-$\alpha$ induced MMP-9 expression, suggesting that ERK activation is required for the MMP-9 induction by TNF-$\alpha$. Taken together, we found that TNF-$\alpha$ stimulation facilitates ERK activation, which results in the transcriptional upregulation of MMP-9 gene and subsequent MMP-9 production and secretion.