• The Korean Journal of Physiology and Pharmacology
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• v.16 no.1
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• pp.31-36
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• 2012

The receptor activator of NF-${\kappa}B$ ligand (RANKL) signal is an activator of tumor necrosis factor receptor-associated factor 6 (TRAF6), which leads to the activation of NF-${\kappa}B$ and other signal transduction pathways essential for osteoclastogenesis, such as $Ca^{2+}$ signaling. However, the intracellular levels of inositol 1,4,5-trisphosphate ($IP_3$) and $IP_3$-mediated cellular function of RANKL during osteoclastogenesis are not known. In the present study, we determined the levels of $IP_3$ and evaluated $IP_3$-mediated osteoclast differentiation and osteoclast activity by RANKL treatment of mouse leukemic macrophage cells (RAW 264.7) and mouse bone marrow-derived monocyte/macrophage precursor cells (BMMs). During osteoclastogenesis, the expression levels of $Ca^{2+}$ signaling proteins such as $IP_3$ receptors ($IP_3Rs$), plasma membrane $Ca^{2+}$ ATPase, and sarco/endoplasmic reticulum $Ca^{2+}$ ATPase type2 did not change by RANKL treatment for up to 6 days in both cell types. At 24 h after RANKL treatment, a higher steady-state level of $IP_3$ was observed in RAW264.7 cells transfected with green fluorescent protein (GFP)-tagged pleckstrin homology (PH) domains of phospholipase C (PLC) ${\delta}$, a probe specifically detecting intracellular $IP_3$ levels. In BMMs, the inhibition of PLC with U73122 [a specific inhibitor of phospholipase C (PLC)[ and of $IP_3Rs$ with 2-aminoethoxydiphenyl borate (2APB; a non-specific inhibitor of $IP_3Rs$) inhibited the generation of RANKL-induced multinucleated cells and decreased the bone-resorption rate in dentin slice, respectively. These results suggest that intracellular $IP_3$ levels and the $IP_3$-mediated signaling pathway play an important role in RANKL-induced osteoclastogenesis.

• Journal of Life Science
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• v.30 no.6
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• pp.501-512
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• 2020

Sasa quelpaertensis Nakai leaf has been used as a folk medicine for the treatment of gastric ulcer, dipsosis, and hematemesis based on its anti-inflammatory, antipyretic, and diuretic characteristics. We have previously reported the procedure for deriving a phytochemical-rich extract (PRE) from S. quelpaertensis and how PRE and its ethyl acetate fraction (EPRE) exhibits an anticancer effect by inducing apoptosis in various gastric cancer cells. To explore the molecular targets involved in this apoptosis, we investigated the mRNA and microRNA profiles of EPRE-treated SNU-16 human gastric cancer cells. In total, 2,875 differentially expressed genes were identified by RNA sequencing, and gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses indicated that the EPRE-modulated genes are associated with apoptosis, mitogen-activated protein kinase, inflammatory response, tumor necrosis factor signaling, and cancer pathways. Subsequently, protein-protein interaction network analysis confirmed interactions among genes associated with cell death and apoptosis, and 27 differentially expressed microRNAs were identified by further sequencing. Here, GO and KEGG pathway analysis revealed that EPRE modified the expression of microRNAs associated with the cell cycle and cell death, as well as signaling of tropomyosin-receptor-kinase receptor, transforming growth factor-b, nuclear factor kB, and cancer pathways. Taken together, these results provide insight into the mechanisms underlying the anticancer effect of EPRE.

• Preventive Nutrition and Food Science
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• v.20 no.4
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• pp.253-259
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• 2015

Chronic low-grade inflammation is associated with obesity. This study investigated effect of high hydrostatic pressure extract of red ginseng (HRG) on inflammation in rats with high-fat (HF) diet induced obesity. Male, Sprague-Dawley rats (80~110 g) were randomly divided into two groups, and fed a 45% HF diet (HF) and a 45% HF diet containing 1.5% HRG (HF+HRG) for 14 weeks. At the end of the experiment, the serum leptin level was reduced by the HRG supplementation. The mRNA expression of genes related to adipogenesis including peroxisome proliferator-activated receptor-gamma and adipocyte protein 2 was down-regulated in the white adipose tissue (WAT). The mRNA levels of major inflammatory cytokines such as tumor necrosis factor-${\alpha}$, monocyte chemoattractant protein 1, and interleukin-6 were remarkably down-regulated by the HRG in WAT. These results suggest that HRG might be beneficial in ameliorating the inflammation-associated health complications by suppressing adipogenic and pro-inflammatory gene expression.

• Clinical and Experimental Pediatrics
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• v.64 no.2
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• pp.68-75
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• 2021

The novel coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has been spreading worldwide since December 2019. Hundreds of cases of children and adolescents with Kawasaki disease (KD)-like hyperinflammatory illness have been reported in Europe and the United States during the peak of the COVID-19 pandemic with or without shock and cardiac dysfunction. These patients tested positive for the polymerase chain reaction or antibody test for SARS-CoV-2 or had a history of recent exposure to COVID-19. Clinicians managing such patients coined new terms for this new illness, such as COVID-19-associated hyperinflammatory response syndrome, pediatric inflammatory multisystem syndrome temporally associated with COVID-19, or COVID-19-associated multisystem inflammatory syndrome in children (MIS-C). The pathogenesis of MIS-C is unclear; however, it appears similar to that of cytokine storm syndrome. MIS-C shows clinical features similar to KD, but differences between them exist with respect to age, sex, and racial distributions and proportions of patients with shock or cardiac dysfunction. Recommended treatments for MIS-C include intravenous immunoglobulin, corticosteroids, and inotropic or vasopressor support. For refractory patients, monoclonal antibody to interleukin-6 receptor (tocilizumab), interleukin-1 receptor antagonist (anakinra), or monoclonal antibody to tumor necrosis factor (infliximab) may be recommended. Patients with coronary aneurysms require aspirin or anticoagulant therapy. The prognosis of MIS-C seemed favorable without sequelae in most patients despite a reported mortality rate of approximately 1.5%.

• BMB Reports
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• v.51 no.6
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• pp.308-313
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• 2018

Small-molecule inhibitors are widely used to treat a variety of inflammatory diseases. In this study, we found a novel anti-inflammatory compound, 1-[(2R,4S)-2-methyl-4-(phenylamino)-1,2,3,4-tetrahydroquinolin-1-yl]prop-2-en-1-one (MPQP). It showed strong anti-inflammatory effects in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. These effects were exerted through the inhibition of the production of NO and pro-inflammatory cytokines, such as interleukin (IL)-6, $IL-1{\beta}$, and tumor necrosis $factor-{\alpha}$ ($TNF-{\alpha}$). Furthermore, MPQP decreased the expression levels of inducible NO synthase (iNOS) and cyclooxygenase 2 (COX-2). Additionally, it mediated the inhibition of the phosphorylation of p38, c-Jun N-terminal kinase (JNK), the inhibitor of ${\kappa}B{\alpha}$ ($I{\kappa}B{\alpha}$), and their upstream kinases, $I{\kappa}B$ kinase (IKK) ${\alpha}/{\beta}$, mitogen-activated protein kinase kinase (MKK) 3/6, and MKK4. Furthermore, the expression of IL-1 receptor-associated kinase 1 (IRAK1) that regulates $NF-{\kappa}B$, p38, and the JNK signaling pathways, was also increased by MPQP. These results indicate that MPQP regulates the IRAK1-mediated inflammatory signaling pathways by targeting IRAK1 or its upstream factors.

• Mycobiology
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• v.38 no.2
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• pp.144-148
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• 2010

$\beta$-Glucans have been known to exhibit antitumor activities by potentiating host immunity by an unknown mechanism. The C-type lectin dectin-1, a $\beta$-glucan receptor, is found on the macrophage and can recognize various $\beta$-glucans. Previously, we demonstrated the presence of $\beta$-glucan receptor, dectin-1, on the Raw 264.7 cells as well as on murine mucosal organs, such as the thymus, the lung, and the spleen. In order to investigate immunopotentiation of innate immunity by $\beta$-glucan, we stimulated a murine macrophage Raw 264.7 cell line with $\beta$-glucans from Pleurotus ostreatus, Saccharomyces cerevisiae, and Laminaria digitata. Then, we analyzed cytokines such as tumor necrosis factor (TNF)-$\alpha$ and interleukin (IL)-6 by reverse transcription-polymerase chain reaction (RT-PCR). In addition we analyzed gene expression patterns in $\beta$-glucan-treated Raw 264.7 cells by applying total mRNA to cDNA microarray to investigate the expression of 7,000 known genes. When stimulated with $\beta$-glucans, the macrophage cells increased TNF-$\alpha$ expression. When co-stimulation of the cells with $\beta$-glucan and lipopolysaccharide (LPS), a synergy effect was observed by increased TNF-$\alpha$ expression. In IL-6 expression, any of the $\beta$-glucans tested could not induce IL-6 expression by itself. However, when co-stimulation occurred with $\beta$-glucan and LPS, the cells showed strong synergistic effects by increased IL-6 expression. Chip analysis showed that $\beta$-glucan of P. ostreatus increased gene expressions of immunomodulating gene families such as kinases, lectin associated genes and TNF-related genes in the macrophage cell line. Induction of TNF receptor expression by FACS analysis was synergized only when co-stimulated with $\beta$-glucan and LPS, not with $\beta$-glucan alone. From these data, $\beta$-glucan increased expressions of immunomodulating genes and showed synergistic effect with LPS.

• BMB Reports
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• v.54 no.11
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• pp.557-562
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• 2021

Microglial activation is closely associated with neuroinflammatory pathologies. The nucleotide-binding and oligomerization domain-like receptor containing a pyrin domain 3 (NLRP3) inflammasomes are highly organized intracellular sensors of neuronal alarm signaling. NLRP3 inflammasomes activate nuclear factor kappa-B (NF-κB) and reactive oxygen species (ROS), which induce inflammatory responses. Moreover, NLRP3 dysfunction is a common feature of chronic inflammatory diseases. The present study investigated the effect of a novel thiazol derivative, N-cyclooctyl-5-methylthiazol-2-amine hydrobromide (KHG26700), on inflammatory responses in lipopolysaccharide (LPS)-treated BV-2 microglial cells. KHG26700 significantly attenuated the expression of several pro-inflammatory cytokines, including tumor necrosis factor-α, interleukin-1β, and interleukin-6, in these cells, as well as the LPS-induced increases in NLRP3, NF-κB, and phospho-IkBα levels. KHG26700 also suppressed the LPS-induced increases in protein levels of autophagy protein 5 (ATG5), microtubule-associated protein 1 light chain 3 (LC3), and beclin-1, as well as downregulating the LPS-enhanced levels of ROS, lipid peroxidation, and nitric oxide. These results suggest that the anti-inflammatory effects of KHG26700 may be due, at least in part, to the regulation of the NLRP3-mediated signaling pathway during microglial activation.

• Korean Journal of Pharmacognosy
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• v.45 no.1
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• pp.28-34
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• 2014

Rhei Rhizoma (RR) and Moutan cortex (MC) have been reported to have anti-inflammatory effects. However, little is known about the effects of RR and MC on endothelial inflammation and insulin resistance (IR). This study aims to investigate whether the water extracts of RR and MC could exert protection against palmitic acid (PA)-induced inflammation and IR in human umbilical vein endothelial cells (HUVECs). HUVECs were pretreated for 6 h with RR or MC, and then exposed to PA for 24 h. The levels of interleukin-6 (IL-6) and tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) were determined by enzyme-linked immunosorbant assay kits. Western blot analysis was performed for activation of nuclear factor-${\kappa}B$ (NF-${\kappa}B$) and insulin receptor substrate-1 (IRS-1). In HUVECs stimulated with PA, both RR and MC significantly inhibited the production of TNF-${\alpha}$ and IL-6 and the activation of NF-${\kappa}B$. At the same concentrations, the inhibitory effects of RR were more potent than those of MC. PA reduced insulin-induced phosphorylation of IRS-1, which was reversed by RR and MC. The results suggest that RR and MC are effective in inhibiting PA-associated endothelial inflammation and ameliorating IR by beneficial regulation of NF-${\kappa}B$ and IRS-1 activation.

• Journal of Microbiology
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• v.37 no.4
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• pp.256-262
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• 1999

Latent membrane protein 1 (LMP1) of the Epstein-Barr virus (EBV) is an integral membrane protein with six transmembrane domains, which is essential for EBV-induced B cell transformation. LMP1 functions as a constitutively active tumor necrosis factor receptor (TNFR) like membrane receptor, whose signaling requires recruitment of TNFR-associated factors (TRAFs) and leads to NF-${\kappa}B$ activation. NF-${\kappa}B$ activation by LMP1 is critical for B cell transformation and has been linked to many phenotypic changes associated with EBV-induced B cell transformation. Deletion analysis has identified two NF-${\kappa}B$ activation regions in the carboxy terminal cytoplasmic domains of LMP1, termed CTAR1 (residues 194-232) and CTAR2 (351-386). The membrane proximal C-terminal domain was precisely mapped to a PXQXT motif (residues 204-208) involved in TRAF binding as well as NF-${\kappa}B$ activation. In this study, we dissected the CTAR2 region, which is the major NF-${\kappa}B$ signaling effector of LMP1, to determine a minimal functional sequence. A series of LMP1 mutant constructs systematically deleted for the CTAR2 region were prepared, and NF-${\kappa}B$ activation activity of these mutants were assessed by transiently expressing them in 293 cells and Jurkat T cells. The NF-${\kappa}B$ activation domain of CTAR2 appears to reside in a stretch of 6 amino acids (residues 379-384) at the end of the carboxy terminus.

• BMB Reports
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• v.40 no.1
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• pp.88-94
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• 2007

Matrix metalloproteinase-9 (MMP-9) plays a pivotal role in the turnover of extracellular matrix (ECM) and in the migration of normal and tumor cells in response to normal physiologic and numerous pathologic conditions. Here, we show that the transcription of the MMP-9 gene is induced by lipopolysaccharide (LPS) stimulation in cells of a macrophage lineage (RAW 264.7 cells). We provide evidence that the NF-$\kappa$B binding site of the MMP-9 gene contributes to its expression in the LPS-signaling pathway, since mutation of NF-$\kappa$B binding site of MMP-9 promoter leads to a dramatic reduction in MMP-9 promoter activation. In addition, the degradation of l$\kappa$B$\alpha$;, and the presences of myeloid differentiation protein (MyD88) and tumor necrosis factor receptor-associated kinase 6 (TRAF6) were found to be required for LPS-activated MMP-9 expression. Chromatin immunoprecipitation (ChIP) assays showed that functional interaction between NF-$\kappa$B and the MMP-9 promoter element is necessary for LPS-activated MMP-9 induction in RAW 264.7 cells. In conclusion, our observations demonstrate that NF-$\kappa$B contributes to LPS-induced MMP-9 gene expression in a mouse macrophage cell line.