• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.2
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• pp.267-272
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• 2017

Piceatannol (PIC) is a natural hydroxylated analog of resveratrol (RSV), which is a polyphenol known to extend lifespan by stimulating sirtuins. The aim of this study was to investigate the effects of PIC and RSV on the toll-like receptor 4 (TLR4)-nuclear factor kappa B ($NF-{\kappa}B$) pathway in mouse hepatocytes and an obese/diabetic KK/HlJ mouse model. AML12 mouse hepatocytes in the absence or presence of palmitic acids (PA) were treated with PIC ($50{\mu}M$) or RSV ($50{\mu}M$). Male KK/HlJ mice at 20 weeks of age were divided into three subgroups as follows: 1) obese and diabetic control (KK), 2) KK_PIC, and 3) KK_RSV. PIC and RSV were administered orally at a dose of 10 mg/kg/d for 4 weeks. Four weeks of PIC and RSV treatment did not affect body weight or food intake in KK mice. Serum fasting blood glucose was significantly reduced in KK_PIC, and 2 h oral glucose tolerance test area under the curve was significantly reduced by PIC and RSV treatment in KK mice. PIC tended to improve homeostasis model assessment of the insulin resistance index (HOMA-IR) and HOMA beta-cells in diabetic KK mice. TLR4 and $NF-{\kappa}B$ were down-regulated by PIC and RSV treatments in hepatocytes in the absence or presence of PA. Insulin receptor, AMP-activated protein kinase, peroxisome proliferator-activated receptor gamma, nucleotide oligomerization domain-like receptor family pyrin domain-containing 3, interleukin-1, and $NF-{\kappa}B$ were altered in PIC-treated livers. Collectively, PIC and RSV inhibited the $TLR4-NF-{\kappa}B$ pathway, and PIC seems to be more effective than RSV in the regulation of analyzed targets, which are involved in insulin signaling and inflammation in vivo.

• The Journal of Korean Medicine
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• v.27 no.1 s.65
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• pp.184-195
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• 2006

Objectives : Betula Platyphylla(BP) is a traditional analgesic, anti-fungal, anti-inflammatory herb used in Chinese 1medicine. However, no information is available to explain its action. In this study. we investigated the anti-inflammatory 1effects of BP to elutidate the molecular pharmacological activity in the ethanol extract of BP(BPE). Methods : We performed WTS assay in lipopolysaccharide (LPS) stimulated RAW264.7 macrophages with BPE. Nitrite was measured by Griess assay, prostaglandin E2 (PGE2) by enzyme-linked immunosorbent assay (ELISA) in LPS induced RAW264.7 macrophages with BPE. Inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX-2) were determined by Western blot. Activation of nuclear factor-kappaB (NF-kB) was measured by electrophoretic mobility shift assay (EMSA). Results : BPE significantly suppressed production of nitric oxide (NO) and PGE2 in LPS-induced RAW264.7 macrophages in a dose-dependent manner. The maximal inhibition rate of NO and PGE2 production by BPE was ca. 88.8% and 93% at the concentration of $100{\mu}g/ml$ (non-cytotoxic concentration), respectively. BPE also decreased iNOS protein and COX-2 protein in LPS-induced RAW264.7 macrophages. EMSA demonstrated that BPE inhibited the DNA binding activity of the NF-kB. Conclusions : These results suggest that BPE inhibits NF-${\kappa}B$-mediated gene expression and downregulates inflammatory mediator production in RAW264.7 macrophages.

• Proceedings of the Korean Society of Toxicology Conference
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• 2002.05b
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• pp.88.2-98
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• 2002

A wide arry of naturally occurring substances particularly those present in dietary and medicinal plants, have been reported to possess substantial cancer chemopreventive properties. Certain phytochemicals retain strong antioxidative and anti-inflammatory properties which appear to contribute to their chemopreventive or chemoprotective activities. Inducible cyclooxygenase(COX-2) and nitric oxide synthase (iNOS) are important enzymes that mediate inflammatory processes. There is some evidence that expression of both COX-2 and iNOS is co-regulated by the eukaryotic transcription factor NF-$textsc{k}$B. Increased expression of COX-2 and/or iNOS has been associated with pathophysiology of certain types of human cancers as well as inflammatory diseases. Since inflammation is closely linked to tumor promotion, substances with potent anti-inflammatory activies are anticipated to exert chemopreventive effects on carcinogenesis, particularly in the promotion stage. An example is curcumin, a yellow pigment of turmeric (Curcuma longa L., Zingiberaceae), that strongly occurring diaryl heptanoids structurally related to curcumin have substantial anti-tumor promotional activities in two-stage mouse skin carcinogenesis. Thus, yakuchinone A [1-(4'-hydroxy-3'-methoxyphenyl)-7-phenyl-3heptanone] and yakuchinone B [1-(4'-hydroxy-3'methoxyphenyl)-7-phenylhept-1-en-3-one] present in Alpinia oxyphylla Miquel (Zingiberacease) attenuate phorbol ester-induced inflammation and papilloma formation in female ICR mice. These diarylheptanoids also suppressed phorbol ester-induced activation of epdermal ornithine decarboxylase and its mRNA expression when applied onto shaven backs of mice. Yakuchinone A and B as well as curcumin inhibited phorbol ester-induced expression of COX-2 and iNOS and their mRNA in mouse skin via inactivation of NF-$textsc{k}$B. Capsaicin, a major pungent ingredient of red pepper also attenuated phorbol ester-induced NF-$textsc{k}$B activation. Similar suppression of COX-2 and iNOS and down-regulation of NF-$textsc{k}$B activation for its DNA binding were observed with the ginsenosied Rg3 and the ethanol extract of Artemisia asiatica. We have also found that certain anti-inflammatory phytochemicals exert inhibitory effects on phorbol ester-induced COX-2 expression and NF-$textsc{k}$B activation in immortalized human breast epithelial (MCF-10A) cells in culture. One of the plausible mechanisms undelying inhibition by aforementioned phytochemicals of phorbol ester-induced NF-$textsc{k}$B activation involves interference with degragation of the inhibitory unit, I$textsc{k}$Ba, which blocks subsequent nuclear translocation of the functionally active p65 subunit of NF-$textsc{k}$B. the activation of epidermal NF-$textsc{k}$B by phorbol ester and subsequent induction of COX-2 hence appear to play an important role in intracellular signaling pathwasy leading to tumor promotion and targeted inhibition of NF-$textsc{k}$B may provide a new promising cancer chemopreventive strategy.

• Research in Plant Disease
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• v.17 no.2
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• pp.169-176
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• 2011

Phytophthora katsurae is the fungus responsible for chestnut ink disease. The objectives of this study were to determine if a single-strand conformation polymorphism (SSCP) analysis of rDNA-ITS region, elongation factor 1 alpha gene and ${\beta}$-tubulin gene could be used for rapid identification and genetic diversity of P. katsurae, and to assess the potential use of the SSCP technique as a diagnostic tool for P. katsurae. Each regions amplified by PCR using primers designed to overlap the genus Phytophthora were characterized for the Phytophthora species. PCR products were denatured and electrophoresed for SSCP analysis. P. katsurae isolates showed an unique pattern in SSCP analysis and were easily distinguished from other Phytophthora species used as the control. This indicates that SSCP analysis is an useful technique for distinguishing Phytophthora species from genetically close relatives, and show that the SSCP analysis of each region is an efficient detection tool for P. katsurae. But PCR-SSCP analysis of single-gene may have difficulty in distinguishing P. katsurae from other Phytophthora species. Therefore, PCR-SSCP analysis of multi-genes can be useful for rapid and effective identification of P. katsurae.

• BMB Reports
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• v.49 no.10
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• pp.554-559
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• 2016

Mycobacterium abscessus, a member of the group of non-tuberculous mycobacteria, has been identified as an emerging pulmonary pathogen in humans. However, little is known about the protective immune response of antigen-presenting cells, such as dendritic cells (DCs), which guard against M. abscessus infection. The M. abscessus gene MAB1843 encodes ᴅ-alanyl-ᴅ-alanine dipeptidase, which catalyzes the hydrolysis of ᴅ-alanyl-ᴅ-alanine dipeptide. We investigated whether MAB1843 is able to interact with DCs to enhance the effectiveness of the host's immune response. MAB1843 was found to induce DC maturation via toll-like receptor 4 and its downstream signaling pathways, such as the mitogen-activated protein kinase and nuclear factor kappa B pathways. In addition, MAB1843-treated DCs stimulated the proliferation of T cells and promoted Th1 polarization. Our results indicate that MAB1843 could potentially regulate the immune response to M. abscessus, making it important in the development of an effective vaccine against this mycobacterium.

• Biomolecules & Therapeutics
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• v.8 no.2
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• pp.140-146
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• 2000

Recently, we reported that immunostimulation of primary rat cortical astrocyte caused stimulation of glucose deprivation induced apoptotic cell death. To enhance the understanding of the mechanism of the potentiated cell death of clucose-deprived astrocyte by immunostimulation, we investigated the effect of immunostimulation on the glucose deprivation induced cell death of rat C6 glioma cells. Co-treatment of C6 glioma cells with lipopolysaccharide (LPS, $1\;{\mu}\textrm{g}/ml$) and interferon ${\gamma}(IFN{\gamma},\;100U/ml)$ is serum free condition caused marked elevationo f nitric oxide production ($>50\;{\mu}M$). In this condition, glucose deprivation caused significant release of lactate dehdrogenase (LDH) from C6 glioma cells while control cells did not show LDH release. To investigate whether elevated level of nitric oxide is responsible for the enhanced LDH release in glucose-deprived condition, C6 glioma cells were treated with 3-morphorinosydnonimine (SIN-1) and it was observed that SIN-1 caused increase in LDH release from glucose-deprived C6 glioma cells. Treatment of C6 glioma cells with $25\;{\mu}M$ of pyrrolidinedithiocarbamate (PDTC) which inhibit Nuclear factor kB (NF-kB) activation, caused complete inhibition of nitric oxide production. Treatment of C6 glioma cells with NO synthase inhibitors, $N^{G}$-nitro-L-arginine (NNA) or L-$N{\omega}$-nitro-L-arginine methyl ester (L-NAME), caused inhibition of nitric oxide production and also glucose deprivation induced cell death of cytokine-stimulated C6 glioma cells. In addition, diaminohydroxypyrimidine (DAHP, 5 mM) which inhibits the synthesis of tetrahydrobiopterine (BH4), one of essential cofactors for iNOS activity, caused complete inhibition of NO production from immunostimulated C6 glioma cells. The results from the present study suggest that immunostimulation causes potentiation of glucose deprivation induced death of C6 glioma cells which is mediated at least in part by the increased production of nitric oxide. The vulnerability of immunostimulated C6 glioma cells to hypoglycemic insults may implicate that the elevated level of cytokines in various ischemic and neurodegenerative diseases may play a role in their pathogenesis.

• Tuberculosis and Respiratory Diseases
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• v.46 no.4
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• pp.533-541
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• 1999

Background: Lung cancer in younger patients seems to be a more aggressive disease and their prognosis may be worse than that of older patients. Abnormal p53 expression in primary lung cancer may be an independent prognostic factor for poor prognosis. This study was conducted to determine the difference of abnormal p53 mutation in patients with primary non-small cell lung cancer (NSCLC) under 45 years of age and 55 years old or greater. Method: The present study was performed to compare the clinical and pathological features of primary NSCLC between patients younger than 45 years old and older than 55 years old and to evaluate the difference of abnormal p53 mutation between two groups. Immunohistochemical detection of abnormal p53 mutation was assessed in all primary NSCLC specimens by pathologist. Results: Positive nuclear staining of p53 mutation was found in 76.0% of younger patients and in 76.9% of older patients with variable intensity of staining. And there was no significant correlation between abnormal p53 mutation according to the disease stage or histologic subtype. Conclusion: In this investigation, these were no difference in p53 mutation between two groups.

• Archives of Pharmacal Research
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• v.25 no.5
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• pp.655-663
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• 2002

Liver fibrosis is a prepathological state wherein damaged liver tissues in chronic liver diseases, such as hepatitis, are not repaired to normal tissues, but converted to fibrous tissue. 5-(2-Pyrazinyl)-4-methyl-1,2-dithiol-3-thione (oltipraz), a cancer chemopreventive agent, is effective against a wide variety of chemical carcinogens. Recently, we reported that oltipraz inhibits liver fibrogenesis (Kang et al., 2002). In the present study, the effects of oltipraz in combination with dimethyl-4,4'-dimethoxy-5,6,5',6'-dimethylene dioxybiphenyl-2,2'-dicarboxylate (DDb) on dimethylnitrosamine (DMN)-induced liver fibrogenesis were assessed in rats. Oltipraz (30 mg/kg body weight, po, 3 times per week for 4 weeks) was found to inhibit the increases in plasma ALT, AST and bilirubin by DMN, whereas DDB (30 mg/kg body weight, po, 3 times per week for 4 weeks) attenuated the increases in the plasma ALT and bilirubin. The lowered plasma protein and albumin contents in DMN-treated rats were completely restored by oltipraz, but not by DDB. DDB decreases liver cell injury and inflammation through inhibition of nuclear factor-kB. DMN increased the accumulation of liver collagen, as indicated by the increase in the 4-hydroxyproline content in liver homogenates, which was reduced by treatment with oltipraz, but not by DDB. Given the differential effect between oltipraz and DDB, the potential enhancement of antifibrotic efficacy by the drugs was assessed in the animal model. Despite the minimal effect of DDB on DMN-induced fibrogenesis, DDB (5-25 mg/kg), administered together with oltipraz (25-5 mg/kg), showed an additive protective effect against hepatotoxicity and fibrosis induced by DMN, which was shown by the blood chemistry parameters and histopathological analysis. The adequate composition ratio of oltipraz to DDB was 5:1. These results provide information on the pharmaceutical composition, comprising of oltipraz and DDB as the active components, for the treatment and/or prevention of liver fibrosis and cirrhosis.

• Journal of Microbiology and Biotechnology
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• v.26 no.2
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• pp.421-431
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• 2016

Recently, poly-γ-glutamic acid synthetase A (pgsA) has been applied to display exogenous proteins on the surface of Lactobacillus casei or Lactococcus lactis, which results in a surface-displayed component of bacteria. However, the ability of carrying genes encoded by plasmids and the expression efficiency of recombinant bacteria can be somewhat affected by the longer gene length of pgsA (1,143 bp); therefore, a truncated gene, pgsA, was generated based on the characteristics of pgsA by computational analysis. Using murine IL-10 as an exogenous gene, recombinant Lactobacillus plantarum was constructed and the capacity of the surface-displayed protein and functional differences between exogenous proteins expressed by these strains were evaluated. Surface expression of IL-10 on both recombinant bacteria with anchorins and the higher expression levels in L. plantarum-pgsA'-IL-10 were confirmed by western blot assay. Most importantly, up-regulation of IL-1β, IL-6, TNF-α, IFN-γ, and the nuclear transcription factor NF-κB p65 in RAW264.7 cells after stimulation with Poly(I:C) or LPS was exacerbated after co-culture with L. plantarum-pgsA. By contrast, IL-10 expressed by these recombinant strains could reduce these factors, and the expression of these factors was associated with recombinant strains that expressed anchorin (especially in L. plantarum-pgsA'-IL-10) and was significantly lower compared with the anchorin-free strains. These findings indicated that exogenous proteins could be successfully displayed on the surface of L. plantarum by pgsA or pgsA', and the expression of recombinant bacteria with pgsA' was superior compared with bacteria with pgsA.

• Journal of Microbiology and Biotechnology
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• v.22 no.3
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• pp.378-384
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• 2012

In aquatic invertebrates, particularly marine gastropods, organotin compounds induce irreversible sexual abnormality in females, which is termed imposex, at very low concentrations. Organotin compounds are agonists for nuclear receptors such as RXRs and $PPAR{\gamma}$. However, the imposex phenomenon has not been reported to act as an antagonist on estrogen receptors in other species, including vertebrates and invertebrates. In order to gain insights into the antagonistic activity of organotin compounds on estrogen receptors (ERs), we examined the inhibitive effect of these compounds on estradiol-dependent ${\beta}$-galactosidase activity using the yeast two-hybrid detection system consisting of a combination of the human estrogen receptor ($hER{\beta}$) ligand-binding domain and the co-activator steroid receptor co-activator-1 (SRC1). Tributyltin-hydroxide (TBT-OH) and triphenyltin-chlorine (TPT-Cl) exhibited an inhibitive effect on $E_2$-dependent transcriptional activity, similar to antagonistic chemicals such as 4-hydroxytamoxifen (OHT) or ICI 182,780, at a very low concentration of $10^{-14}$ M TBT or $10^{-10}$ M TPT, respectively. The yeast growth and transcriptional activity with transcriptional factor GAL4 did not exhibit any effect at the tested concentration of TBT or TPT. Moreover, the yeast two-hybrid system using the interaction between p53 and the T antigen of SV40 large did not describe any effect at the tested concentration of OHT or ICI 182,780. However, the interaction between p53 and T antigen was inhibited at a TBT or TPT concentration of $10^{-9}$ M, respectively. These results indicate that TBT and TPT act as inhibitors of ER-dependent reporter gene transcriptional activation and of the interaction between $hER{\beta}$ LBD and the co-activator SRC1 in the yeast two-hybrid system. Consequently, our data could partly explain the occurrence of organotin compound-induced imposex on the endocrine system of mammals, including humans.