• The Korean Journal of Physiology and Pharmacology
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• v.4 no.1
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• pp.47-54
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• 2000

Transition metal ions including $Se^{2+},\;Cd^{2+},\;Hg^{2+}\;or\;Mn^{2+}$ have been thought to disturb the bone metabolism directly. However, the mechanism for the bone lesion is unknown. In this study, we demonstrated that MC3T3E1 osteoblasts, exposed to various transition metal ions; selenium, cadmium, mercury or manganese, generated massive amounts of reactive oxygen species (ROS). The released ROS were completely quenched by free radical scavengers-N-acetyl cysteine (NAC), reduced glutathione (GSH), or superoxide dismutase (SOD). First, we have observed that selenium $(10\;{\mu}M),$ cadmium $(100\;{\mu}M),$ mercury $(100\;{\mu}M)$ or manganese (1 mM) treatment induced apoptotic phenomena like DNA fragmentation, chromatin condensation and caspase-3-like cysteine protease activation in MC3T3E1 osteoblasts. Concomitant treatment of antioxidant; N-acetyl-L-cysteine (NAC), reduced-form glutathione (GSH), or superoxide dismutase (SOD), prevented apoptosis induced by each of the transition metal ions. Catalase or dimethylsulfoxide (DMSO) has less potent inhibitory effect on the apoptosis, compared with NAC, GSH or SOD. In line with the results, nitroblue tetrazolium (NBT) stain shows that each of the transition metals is a potent source of free radicals in MC3T3E1 osteoblast. Our data show that oxidative damage is associated with the induction of apoptosis in MC3T3E1 osteoblasts following $Se^{2+},\;Cd^{2+},\;Hg^{2+}\;or\;Mn^{2+}$ treatment.

• Journal of Applied Biological Chemistry
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• v.57 no.2
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• pp.179-182
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• 2014

In the present study, we investigated the effects of methanol extracts from Alpinia katsumadai Hayata against antiviral potential underlying mechanism in glucosidase inhibition. Syncytium formation in Newcastle disease virus (NDV)-infected baby hamster kidney (BHK) cell originates from the trafficking of viral glycoprotein into cell-surface. Methanol extracts inhibited not only syncytium formation, but also trafficking of glycoprotein, hemagglutinin-neuraminidase (HN), onto cell-surface. A. katsumadai extracts showed the inhibitory activities ($IC_{50}$ $25{\mu}g/mL$) against ${\alpha}$-glucosidase. These results suggested that blue chanterelle extracts inhibited the cell-surface expression of NDV-HN glycoprotein without significantly affecting HN glycoprotein synthesis in NDV-infected BHK cells.

• Korean Journal of Microbiology
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• v.54 no.3
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• pp.208-213
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• 2018

Activation of nuclear factor kappa B ($NF{\kappa}B$) leads to the inflammatory process. During this $NF{\kappa}B$-dependent inflammation process, inducible nitric oxide synthase (iNOS) are expressed in the inflammatory cells. Our previous data indicated that a specific septapeptide (GVAWWMY) from the soybean extract fermented by Bacillus licheniformis B1 inhibited iNOS mRNA expression and NO production in cultured macrophage cells. Our further experiments revealed that treatment of same septapeptide resulted in inhibition of LPS-induced $NF{\kappa}B$ activation by reversing degradation of $I{\kappa}B{\alpha}$, an inhibitory protein for $NF{\kappa}B$. The molecular docking indicated that the septapeptide binds to $I{\kappa}B$ kinase ${\beta}$ ($IKK{\beta}$), and thus it can inhibit phosphorylation of $I{\kappa}B{\alpha}$. Supporting this, the binding site for the septapeptide has the highest affinity (-8.7 kcal/mol) and the site was located at the kinase domain (KD) of $IKK{\beta}$, which can significantly affect the kinase activity of $IKK{\beta}$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.1
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• pp.44-48
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• 2015

To investigate the anti-cancer effect of shiitake mushrooms (Lentinus edodes) cultured in aloe-supplement, we treated extract of shiitake mushroom cultured in aloe-supplement (ESA) to MDA-MB-231 human breast cancer cells. ESA-treated MDA-MB-231 cells showed decreased growth rate in XTT assay. In addition migration/invasion was noticeably inhibited by ESA in TNF-${\alpha}$-treated MDA-MB-231 cells. Western blot analysis showed that the molecular mechanism of cell migration/invasion was mediated by reduced intercellular adhesion molecule-1 expression via p-ERK signal transduction pathways. We found ESA had inhibition activity against cellular growth and migration/invasion. Taken together, ESA has putative anti-cancer activity against human breast cancer.

• Experimental and Molecular Medicine
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• v.50 no.12
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• pp.1.1-1.14
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• 2018

DNA methylation is a regulatory mechanism in epigenetics that is frequently altered during human carcinogenesis. To detect critical methylation events associated with gastric cancer (GC), we compared three DNA methylomes from gastric mucosa (GM), intestinal metaplasia (IM), and gastric tumor (GT) cells that were microscopically dissected from an intestinal-type early gastric cancer (EGC) using methylated DNA binding domain sequencing (MBD-seq) and reduced representation bisulfite sequencing (RRBS) analysis. In this study, we focused on differentially methylated promoters (DMPs) that could be directly associated with gene expression. We detected 2,761 and 677 DMPs between the GT and GM by MBD-seq and RRBS, respectively, and for a total of 3,035 DMPs. Then, 514 (17%) of all DMPs were detected in the IM genome, which is a precancer of GC, supporting that some DMPs might represent an early event in gastric carcinogenesis. A pathway analysis of all DMPs demonstrated that 59 G protein-coupled receptor (GPCR) genes linked to the hypermethylated DMPs were significantly enriched in a neuroactive ligand-receptor interaction pathway. Furthermore, among the 59 GPCRs, six GI hormone receptor genes (NPY1R, PPYR1, PTGDR, PTGER2, PTGER3, and SSTR2) that play an inhibitory role in the secretion of gastrin or gastric acid were selected and validated as potential biomarkers for the diagnosis or prognosis of GC patients in two cohorts. These data suggest that the loss of function of gastrointestinal (GI) hormone receptors by promoter methylation may lead to gastric carcinogenesis because gastrin and gastric acid have been known to play a role in cell differentiation and carcinogenesis in the GI tract.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.31 no.1 s.49
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• pp.25-33
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• 2005

Melanocytes synthesize melanin within discrete organelle termed melanosomes which are transferred to the surrounding keratinocytes and can be produced in varying sizes, numbers and densities. Skin whitening products have become increasingly popular in the past few years. The most successful natural skin whitening agents are: arbutin, vitamin C, kojic acid, and mulberry, which are all tyrosinase inhibitors. In this work, melanoston, a melanogenesis inhibitor isolated from yeast was studied to understand its mechanism of melanogenesis inhibition. It was found that melanoston was not a tyrosinase inhibitor, while when melanoston was applied to the B16 melanoma cell culture media, the intracellular tyrosinase activity was decreased by more than $30\%$. When B16 melanoma was stimulated with $\alpha$-MSH, cell morphololgy was dramatically changed to have lots of dendrites on the cell membrane surface. On the other hand, B16 was treated with $\alpha$-MSH and melanoston, simultaneously, the change of cell morphologv was not so great. This inhibitory effect of melanoston was found to be related to the inhibition of intracellar activation and transportation of tyrosinase, which was observed by irmmunostaining of B16 melanoma using anti-tyrosinase antibody. From these results, melanoston was regarded as an inhibitor to the differentiation of melanoma cells.

• Archives of Pharmacal Research
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• v.27 no.1
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• pp.77-82
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• 2004

DA-125, a novel derivative of adriamycin, is known for its anti-cancer activity. In this study, the inhibitory mechanism of DA-125 on topoisomerase was investigated in the simian virus 40 (SV40) replicating CV-1 cell by studying the SV40 DNA replication intermediates and DNA-topoisomerase complexes. DNA-protein complexes that were formed in the drug-treated cells were quantitated by using a glass filter assay. SV40 DNA replication intermediates that were accumulated in the drug-treated CV-1 cell were analyzed in a high resolution gel. DA-125 did not accumulate B-dimers of SV40 DNA replication intermediates which were found in the adriamycin-treated CV-1 cells. DA-125 induced a dose-dependent formation of the DNA-protein complexes, while adriamycin did not. When adriamycin and etoposide (VP16) were added to the SV40-infected cells at the same time, adriamycin blocked the formation of the DNA-protein complexes induced by VP16 in a dose-dependent manner. However, DA-125 blocked the formation of the DNA-protein complexes induced by VP16 up to the maximum level of the DNA-protein complexes that were induced by DA-125 alone. Adriamycin and DA-125 did not inhibit the formation of the DNA-protein complexes that were caused by camptothecin, a known topoisomerase I poison. DA-125 is bifunctional in inhibiting topoisomerase II because it simultaneously has the properties of the topoisomerase II poison and the DNA intercalator. As a topoisomerase II poison, DA-125 alone induced dose-dependent formation of the DNA-protein complexes. However, as a DNA intercalator, it quantitatively inhibited the formation of the DNA-protein complexes induced by a strong topoisomerase II poison VP16. Furthermore considering that the levels of the DNA-protein complex induced by VP16 were decreased by DA-125 in terms of the topoisomerase II poison, we suggest that DA-125 has a higher affinity to the drug-binding sites of DNA than VP16 has.

• Journal of Life Science
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• v.31 no.10
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• pp.954-959
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• 2021

Apoptosis is an important mechanism that regulates cellular populations to maintain homeostasis, and the caspases, a family of cysteine proteases, are key mediators of the apoptosis pathway. Caspase-8 is an initiator caspase of the extrinsic apoptotic pathway, which is initiated by extracellular stimuli. Caspase-8 have two conserved domains, N-terminal tandem death effector domains (DED) and C-terminal two catalytic domain, which are important for this extrinsic apoptosis pathway. In extrinsic apoptosis pathway, death receptors which members of TNF superfamily are activated by binding of death receptor specific ligands from cell outside. After the activated death receptors recruit adaptor protein Fas-associated death domain protein (FADD), death domains (DD) of death receptor and FADD bind to each other and FADD combined with death receptor recruits procaspase-8, a precursor form of caspase-8. The DED of FADD and procaspase-8 bind to one another and FADD-bound procaspase-8 is activated by cleavage of the prodomain. This death receptor-FADD-caspase-8 complex called death inducing signaling complex (DISC). Cellular FLICE-inhibitory proteins (c-FLIPs) regulate caspase-8 activation by acting both anti- and pro-apoptotically, and caspase-8 activation initiates the activation of executioner caspases such as caspase-3. Finally activated executioner caspases complete the apoptosis by acting critically DNA degradation, nuclear condensation, plasma membrane blebbing, and the proteolysis of certain caspase substrates.

• Nutrition Research and Practice
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• v.15 no.6
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• pp.686-702
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• 2021

BACKGROUND/OBJECTIVES: Schisandrae Fructus, the fruit of Schisandra chinensis Baill., has traditionally been used as a medicinal herb for the treatment of various diseases, and has proven its various pharmacological effects, including anti-inflammatory and antioxidant activities. In this study, we investigated the inhibitory effect of Schisandrae Fructus ethanol extract (SF) on inflammatory and oxidative stress in particulate matter 2.5 (PM2.5)-treated RAW 264.7 macrophages. MATERIALS/METHODS: To investigate the anti-inflammatory and antioxidant effects of SF in PM2.5-stimulated RAW 264.7 cells, the levels of pro-inflammatory mediator such as nitric oxide (NO) and prostaglandin E₂ (PGE₂), cytokines including interleukin (IL)-6 and IL-1β, and reactive oxygen species (ROS) were measured. To elucidate the mechanism underlying the effect of SF, the expression of genes involved in the generation of inflammatory factors was also investigated. We further evaluated the anti-inflammatory and antioxidant efficacy of SF against PM2.5 in the zebrafish model. RESULTS: The results indicated that SF treatment significantly inhibited the PM2.5-induced release of NO and PGE₂, which was associated with decreased inducible NO synthase and cyclooxygenase-2 expression. SF also attenuated the PM2.5-induced expression of IL-6 and IL-1β, reducing their extracellular secretion. Moreover, SF suppressed the PM2.5-mediated translocation of nuclear factor-kappa B (NF-κB) from the cytosol into nuclei and the degradation of inhibitor IκB-α, indicating that SF exhibited anti-inflammatory effects by inhibiting the NF-κB signaling pathway. In addition, SF abolished PM2.5-induced generation of ROS, similar to the pretreatment of a ROS scavenger, but not by an inhibitor of NF-κB activity. Furthermore, SF showed strong protective effects against NO and ROS production in PM2.5-treated zebrafish larvae. CONCLUSIONS: Our findings suggest that SF exerts anti-inflammatory and antioxidant effects against PM2.5 through ROS-dependent down-regulating the NF-κB signaling pathway, and that SF can be a potential functional substance to prevent PM2.5-mediated inflammatory and oxidative damage.

• Journal of Life Science
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• v.29 no.9
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• pp.1016-1022
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• 2019

Owing to increased interest in preventing obesity in an aging society, both men and women spend considerable amount of cost on obesity managements. In this study, we investigated the natural substances on anti-obesity activities in 3T3-L1 pre-adipocytes. Also, to improve anti-obesityeffects, research using 3T3-L1 pre-adipocytes cells is crucial. The anti-obesity effect of 70% ethanol extract from Torilis Japonica Decandolle on the differentiation of 3T3-L1 pre-adipocytes to adipocytes was investigated by suppressing adipocyte differentiation and lipid accumulation with Oil Red O assay, and western blot analysis. Compared to the control, 70% ethanol extract of Torilis Japonica Decandolle was significantly inhibited adipocyte differentiation and intracellular triglyceride (TG) level at a concentration of $100{\mu}g/ml$. To determine the mechanism of reduction in TG content, we determined the level of protein expression of obesity-related proteins, such as peroxisome-proliferatorsactivated-receptor-${\gamma}$ ($PPAR{\gamma}$) and CCAAT enhancer-binding-proteins-${\alpha}$ ($C/EBP{\alpha}$), and Acetyl-CoA carboxylase (ACC) phosphorylation. As a results, 70% ethanol extract of Torilis Japonica Decandolle significantly decreased protein expression of $PPAR{\gamma}$, $C/EBP{\alpha}$ and ACC phosphorylation. These results indicate that 70% ethanol extract of Torilis Japonica Decandolle is the most effective candidate for preventing obesity. However further studies will be needed to identify the active compounds that confer the anti-obesity activity of Torilis Japonica Decandolle.