• Journal of Microbiology
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• v.44 no.6
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• pp.665-670
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• 2006

Amyloid $\beta$-peptide (A$\beta$), which is a product of the proteolytic effect of $\beta$-secretase (BACE) on an amyloid precursor protein, is closely associated with Alzheimer's disease (AD) pathogenesis. There is sufficient evidence to suggest that a BACE inhibitor may reduce A$\beta$ levels, thus decreasing the risk of AD. In a previous study, an extract of Clavicorona pyxidata DGUM 29005 mycelia was found to inhibit the production of a soluble $\beta$-amyloid precursor protein (s$\beta$APP), A$\beta$, and BACE in neuronal cell lines. We sought to determine whether this mycelial extract exerts the same effect in human rhabdomyosarcoma A-204 and rat pheochromocytoma PC-12 cells. We found that the production of A$\beta$ decreased in a dose-dependent manner in the presence of the mycelial extract and that the concentration of A$\beta$ never exceeded $50{\mu}g/ml$. The presence of sAPP was detected in every culture medium to which the mycelial extract had been added and its concentration remained the same, regardless of the concentration of the extract used. Endogenous $\beta$-secretase activity in A-204 and PC-12 cellular homogenates also decreased in the presence of this extract. These cells, in culture, were not susceptible to the cytotoxic activity of the mycelial extract.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.18 no.2
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• pp.286-297
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• 1996

The proliferation of bone marrow stem cell compartment is thought to be under both positive and negative controls by cytokines and colony stimulation factors. Macrophage inflammatory $protein-1{\alpha}(MIP-1{\alpha})$ has been assessed for its potential to protect hematopoietic stem cells from cytotoxic effects of a cycle-specific antineoplastic agents. We have tested the ability of $MIP-1{\alpha}$ to suppress the proliferation of stem cell line Du.528.101 in variety of active status by using $[^{3}H]-thymidine$ incorporation test. The results were as follows. 1. The effect of $MIP-1{\alpha}$ on steady-state Du.528.101 cell represented the cell growth suppression at the concentration of 10, 50, 100nM of $MIP-1{\alpha}$(P<0.001). 2. $MIP-1{\alpha}$ stimulated the proliferation of Du.528.101 cells previously treated with IL-1 at the concentration of 5, 50nM of $MIP-1{\alpha}$(P<0.01). 3. The suppression effect of MIP-1 on Du.528.101 cells at the concentration of 5, 50nM was shown when cells were treated with $MIP-1{\alpha}$ before activation with $IL-1{\beta}(P<0.01)$. 4. The growth rate of synchronized cells were slower than that of non-synchronized ones, and $MIP-1{\alpha}$ represented the similar suppression effect on both synchronized and non-synchronized cells.

• Journal of Physiology & Pathology in Korean Medicine
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• v.16 no.2
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• pp.338-342
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• 2002

In order to evaluate the effect of Ginseng Radix(GR) against endocrine disrupting chemicals(EDC), cultured mouse osteoblasts were preincubated with various concentrations of GR extract before the exposure of Bisphenol A for 12 hours. Cytotoxic effect of Bisphenol A was measured by the XTT assay. In addition, the protective effect of GR over Bisphenol A-induced cytotoxicity on osteoblasts was assessed by the DNA and protein synthesis in these cultures. The results were as follows : Osteoblastic cell viability was decreased in dose and time dependent manner after exposed to various concentrations of Bisphenol A. Midcytotoxicity value(MCV50) of Bisphenol A was determined at 6μM Bisphenol A after osteoblasts were grown for 12 hours in the media containing various concentrations of Bisphenol A. Amount of DNA synthesis was increased in dose-dependent manner after cultured osteblasts were pretreated with GR for 2hrs before exposure to Bisphenol A for 12 hours. Amount of protein synthesis was increased in dose-dependent manner after cultured osteoblasts were pretreated with GR for 2 hours before exposure of Bisphenol A for 12 hours. From these results, it is suggested that Bisphenol A was highly toxic by the decrease of the cell viability, and GR is effective in the prevention of Bisphenol A-induced cytotoxicity by the increase of DNA and protein syntheses in cultured mouse osteoblasts.

• BMB Reports
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• v.31 no.4
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• pp.355-363
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• 1998

MHC unrestricted, antigen nonspecific killing by $CD4^+$ T-cells against virally-infected target cells was induced following cross-linking of CD4 molecules. The cytotoxicity of antibody-activated $CD4^+$ T-cells was abolished by genistein (4',5,7-trihydroxyisoflavone), a protein tyrosine kinase (PTK) inhibitor, but not by H-7, a protein kinase C (PKC) inhibitor. Genisteintreated human or bovine peripheral blood $CD4^+$ T-cells lacked PTK activity and failed to kill virally-infected target cells even after cross-linking of CD4 molecules. The cross-linking of CD4 molecules did not induce effector cell proliferation or the transcription of TNF ${\beta}$. TNF ${\beta}$ synthesis was up-regulated by incubating antibody activated effector cells with bovine herpesvirus type 1 (BHV-1) infected D17 target cells. Anti-TNF ${\beta}$ antibody partially abrogated direct effector cell-mediated antiviral cytotoxicity. On the other hand, this antibody effectively neutralized antiviral activity of effector and target cell culture supernatants against BHV-1 infected D17 cells. The inhibition level of the antiviral activity by the antibody was dependent on effector and target cell ratio. These findings have importance to define the mechanisms of how CD4 cytotoxic cells control viral infection.

• The Korean Journal of Physiology and Pharmacology
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• v.21 no.3
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• pp.287-292
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• 2017

Vitiligo is an intriguing depigmentary disorder and is notoriously difficult to be treated. The ultimate goal of vitiligo treatment is to replenish the lost melanocytes by immigration from hair follicle and to restore the normal function of melanogenesis by residual melanocytes. There are two types of topical calcineurin inhibitors called tacrolimus and pimecrolimus, and are recommended as the first-line treatments in vitiligo. Although pimecrolimus is efficacious for the repigmentation of vitiligo, its intrinsic mechanisms have never been investigated in vitro. This research aimed to study the ability of pimecrolimus on stimulating melanogenesis, melanocyte migration and MITF (microphthalmia associated transcription factor) protein expression. Results showed that pimecrolimus at the dosages of 1, 10, $10^2$nM were neither mitogenic nor cytotoxic to melanocytes. The addition of pimecrolimus at 10, $10^2$ and $10^3nM$ significantly increased intracellular tyrosinase activity, which was consistent with the elevated content of melanin content at the same concentrations. The peak effect was seen at 72 h in response to $10^2$nM pimecrolimus. Results of the wound scratch assay and Transwell assays indicate that pimecrolimus is effective in facilitating melanocyte migration on a collagen IV-coated surface. In addition, MITF protein yield reached the highest by pimecrolimus at $10^2nM$. In brief, pimecrolimus enhances melanin synthesis as well as promotes migration of melanocytes directly, possibly via their effects on MITF protein expression.

• Journal of Microbiology and Biotechnology
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• v.21 no.8
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• pp.791-795
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• 2011

Sea tangle, a kind of brown seaweed, was fermented with Lactobacillus brevis BJ-20. The gamma-aminobutyric acid (GABA) content in fermented sea tangle (FST) was 5.56% (w/w) and GABA in total free amino acid of FST was 49.5%. The effect of FST on the enzyme activities and mRNA protein expression of alcohol dehydrogenase (ADH) and acetaldehyde dehydrogenase (ALDH) involved in alcohol metabolism in Saccharomyces cerevisiae was investigated. Yeast was cultured in YPD medium supplemented with different concentrations of FST powder [0, 0.4, 0.8, and 1.0% (w/v)] for 18 h. FST had no cytotoxic effect on the yeast growth. The highest activities and protein expressions of ADH and ALDH from the cell-free extracts of S. cerevisiae were evident with the 0.4% and 0.8% (w/v) FST-supplemented concentrations, respectively. The highest concentrations of GABA as well as minerals (Zn, Ca, and Mg) were found in the cell-free extracts of S. cerevisiae cultured in medium supplemented with 0.4% (w/v) FST. The levels of GABA, Zn, Ca, and Mg in S. cerevisiae were strongly correlated with the enzyme activities of ADH and ALDH in yeast. These results indicate that FST can enhance the enzyme activities and protein expression of ADH and ALDH in S. cerevisiae.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2011.10a
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• pp.16-16
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• 2011

Melanogenesis is a well-known physiological response of human skin that may occur because of exposure to ultraviolet light, for genetic reasons, or due to other causes. In our effectors to find new skin lightening agents, acanthoic acid (AA) was investigated for its ability to inhibit melanogenesis. The effects of AA isolated from A.koreanumun the expression of $\alpha$-MSH-induced melanogenic factors (tyrosinase, tyrosinase related protein (TRP)-1, TRP-2 and MITF (microphthalmla-associated transcriptional factor)) were investigated in murine B16F10 melanoma cells. The results indicate that AA was an effective inhibitor of melanogenesis in B16F10 cells. To elucidate the mechanism of the effect of AA on melanogenesis, we performed Western blotting for melanogenic proteins. AA inhibited melanogenic factors (tyrosinase, TRP-1, TRP-2) expressions. In this study, we also confirmed that AA decreased the protein level of MITF proteins, which would lead to a decrease of tyrosinase and related genes in B16F10 melanoma cells. In order to apply AA to the human skin, the cytotoxic effects of the AA were determined by MTT assays using human keratinocyte HaCaT cells. Based on these results, we suggest that AA be considered possible anti-melanogenic agent and might be effective against hyperpigmentation disorders for the topical application.

• KSBB Journal
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• v.31 no.4
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• pp.284-290
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• 2016

In this research, recombinant human cytotoxic T-lymphocyte antigen 4-immunoglobulin (hCTLA4Ig) was produced by transgenic rice cells. RAmy3D promoter was used for overcome the limitation of low expression level in transgenic plant cells, and the secretion of target protein was accomplished by signal peptide. However, the RAmy3D promoter system which can be induced only by sugar starvation causes the decrease of cell viability. As a result, cell death promotes the release of protease which degrades the target proteins. The protein stability and productivity can be significantly influenced by proteolysis activity. Therefore, development of new strategies are necessary for the in situ recovery of target proteins from cell culture media. In this study, in situ recovery was performed by various strategies. Direct addition of Protein A resin with nylon bag leads to cell death by increased shear stress and decrease in production of hCTLA4Ig by protease. Medium exchange through modified flask could recover hCTLA4Ig with high cell viability and low protease activity, on the other hand, the productivity was lower than that of control. When in situ recovery was conducted at day 7 after induction in air-lift bioreactor, 1.94-fold of hCTLA4Ig could be recovered compared to control culture without in situ recovery. Consequently, in situ recovery of hCTLA4Ig from transgenic rice cell culture could enhance productivity significantly and prevent degradation of target proteins effectively.

• BMB Reports
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• v.39 no.5
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• pp.560-570
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• 2006

Mistletoe (Viscum album) lectins, which are classified as a type II ribosome-inactivating protein (RIP) due to their unique biological function and the potential medical and therapeutic application in cancer cells, receive a rising attention. The heterodimeric glycoproteins contain the A-chain with catalytic activity and the B-chain with sugar binding properties. In recent years, studies involving the lectins from the white berry European mistletoe (Viscum album) and the yellow berry Korean mistletoe (Viscum album coloratum) have been described. However, the detailed mechanism in exerting unique cytotoxic effect on cancer cells still remains unclear. Here, we aim to understand and define the molecular basis and biological effects of the type II RIPs, through the studies of the recombinant Korean mistletoe lectin. To this end, we expressed, purified the recombinant Korean mistletoe lectin (rKML), and investigated its molecular characteristics in vitro, its cytotoxicity and ability to induce apoptotic cell death in cancer cells. To gain structural basis for its catalytic activity and sugar binding properties, we performed homology modeling studies based on the high degree of sequence identity and conserved secondary structure prediction between Korean and European, Himalayan mistletoe lectins, and Ricin.

• Journal of Haehwa Medicine
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• v.13 no.2
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• pp.131-146
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• 2004

In the present study, we exarnined anti-allergic effect of SGBHB in cultured B cells. B cells were prepared from isolated murine splenocytes and activated by co-treatment of anti-CD40 monoclonal antibody and recombinant IL-4 allergens. Anti-allergic effects of SGBHB in activated B cells were determined by measuring B cell surface activated molecules (CD23+ and CD11a+), and expression levels of IL-$1{\beta}$, IL-6, IL-10, TNF-$\alpha$, IgE, and HRF. The major findings are summarized as follows. 1. SGBHB treatment did not produce significant cytotoxic effects on mouse lung fibroblast cells. 2. SGBHB produced significant inhibitory effect on the expression of B cell surface activated molecules (CD23+ and CD11a) in activated B cells. 3. SGBHB treatment significantly inhibited expression levels of IL-$1{\beta}$, IL-6, and TNF-$\alpha$ mRNAs in activated B cells.IL-6 protein levels were significantly decreased by $100{\mu}g/m{\ell}$ of SGBHB treatrrient, and TNF-$\alpha$ protein levels were decreased compared to the control group, but statistically insignificant. 4. SGBHB treatment significantly increased IL-10 at both mRNA and protein levels in activated B cells. 5. SGBHB treatment significantly inhibited levels of IgE production. Thus, the present data suggest that SGBHB has an anti-allergic effect on activated B cells by controlling irnmune responses, and further implicates the possibility on clinical application as a therapeutic agent.