• KSBB Journal
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• v.15 no.6
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• pp.621-629
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• 2000

A marine bacterium producing carotenoid was isolated from the Yosu coastal area of South Korea, and has been recorded as MCPBK-1. It was identified as Curtobacterium sp.. The optimum conditions of marine carotenoid fermentation from Cutobacterium sp. were pH 7.0, a temperature of $25^{\circ}C$, 4 mM fructose as a carbon source, 0.07% tryptone as a nitrogen source, 0.5 mM $M^{+2}$ ion as a mineral source and $1{\;}\mu\textrm{M}$ of cyanocobalamine as a growth factor in a $7{\;}\ell$ jar-fermentor. 13.0 mg/ml of the marine carotenoid were produced under optimum conditions. The crude marine carotenoid isolated was composed of 5 different compounds, i.e : tunaxanthin(86.6%), diatoxanthin (7.1%), ${\beta}-carotene$ (2.1%), canthaxanthin(1.9%) and cynthiaxanthin (1.9%). Physiological properties including antibacterial activity, cytotoxic effect, antioxidative effect and free radical scavenging activity were characterized with the crude carotenoid, which exhibited no antibacterial activity against E. coli and Lactobacillus bulgaricus, but a strong cytotoxic effect against cancer cells such as HepG2 (Hepatocellular carcinoma, human, ATCC HB-8065) and HeLa (Cervical carcinoma, human, ATCC CCL-2) cells, the ratios of impediment were 86.4% and 39.2%, respectively. This carotenoid, also, expressed a strong antioxidative effect (83%) against CCL-13 (diploid, monotypic hepatocyte, human, ATCC CCL-13) and exhibited free radical scavenging activity (43.4%) when using at a concentration of $50{\;}\mu\textrm{g}/ml$ of the crude carotenoid.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1997.04a
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• pp.81-81
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• 1997

We previously demonstrated an enhancer-like positive regulatory element within a 259-bp sequence (-2352 to-2094 bp) of the human CYP1A2 gene in HepG2 cells. Three protein binding sites were identified by DNase I footprint analyses within the 259-bp sequence: protected region A PRA ( -2283 to-2243 bp), PRB (-2218 to-2187 bp), and PRC (-2124 to-2098 bp) (I. Chung and E. Bresnick, Mol. Pharmacol. 47, 677-685, 1995). In the present study, the functional significance of those protected regions was examined. Transfection experiments with deletion and substitution mutants defined the PRB and PRC as containing positive and negative regulatory elements, respectively. Human breast carcinoma MCF-7 cells were cotransfected with a hepatocyte nuclear factor-1 (HNF-1) expression vector and CYP1A2 promoter-or thymidine kinase promoter-luciferase remoter gene constructs. HNF-1, which contributes to the liver specificity of genes, enhanced reporter gene activity in a PRC sequence-dependent manner. These results suggested that PRC could exist bound to a repressor which was displaceable by other transcription factors such as HNF-1. Results obtained by transfection of HepG2 hepatoma cells with various PRB substitution mutant-luciferase gene fusion constructs indicated that the entire sequence of PRB was necessary for promoter activity. Consequently, the regulation of CYP1A3 expression is very complex, requiring a number of both positive and negative regulatory factors.

• Molecular & Cellular Toxicology
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• v.5 no.1
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• pp.7-13
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• 2009

In this study, we investigated the anti-proliferative effect of Damina 909 in human cancer cell lines and tumor-xenografted nude mice to elucidate its potential in treating many cancers. Damina 909 treatment resulted in inhibition of cell proliferation of human pancreatic cancer cells. Our in vivo study showed that the weight of pancreatic tumors in Damina 909-treated group were the lighter than control group. Consequently, the intake of food and water in Damina 909-treated group did not change, while those in control group were steadily decreased over a period of treatment. Moreover, Damina 909 treatment elevated the protein expression of p53 and p21 in pancreatic tumor of xenografted nude mice. In summary, compare to other human cancer cells such as prostate and hepatocyte, Damina 909 is most effectively inhibited proliferation of pancreatic cancer cells by increasing the expression of tumor suppressor genes. This led us to speculate that a candidate substance for effective cancer therapy of pancreatic cancer might be contained in Damina 909.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.23 no.3
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• pp.273-286
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• 2013

Objectives: The present study was conducted in order to investigate the reproductive toxicity in rats exposed to 1,4-dichlorobutane. Methods: The test chemical was administered orally at 0, 8.3, 50 and 300 mg/kg/day. Males were administered daily for 10 weeks prior to the mating period. Females were administered from between two weeks before mating to the 21stday of lactation. Results: In both sexes, a decrease in body weight and an increase in the weights of the liver and kidneys were observed. In males, discoloration of the liver, hepatocyte hypertrophy and mineralization in the kidneys were observed. In females, animal deaths, dystocia and pup deaths due to maternal dysfunction were observed. In F1 animals of both sexes, a decrease in body weight was observed at 300 mg/kg/day. An increase in the weights of the liver in both sexes, mineralization in the kidneys of males, animal deaths, hepatocyte hypertrophy and pup deaths due to maternal dysfunction were observed at 50 mg/kg/day. Mineralization in the kidneys of males was observed at 8.3 mg/kg/day. Therefore, the no-observed-adverse-effect levels (NOAELs) of 1,4- dichlorobutane were considered to be under 8.3 mg/kg/day for males, 8.3 mg/kg/day for females, more than 300 mg/kg/day for fertility in both sexes, 8.3 mg/kg/day for maternal functions and 50 mg/kg/day for F1 offspring. The absolute toxic dose was believed to be 8.3 mg/kg/day for males, 50 mg/kg/day for females, 50 mg/kg/day for maternal functions and 300 mg/kg/day for F1 offspring. However NOAEL for fertility could not be determined since there were no treatment-related changes. Conclusions: Under the present experimental conditions, 1,4-dichlorobutane is a Category 1B Reproductive Toxicant (presumed human reproductive or developmental toxicant).

• Radiation Oncology Journal
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• v.33 no.4
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• pp.328-336
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• 2015

Purpose: Past studies have reported that S-allylcysteine (SAC) inhibits the migration and invasion of cancer cells through the restoration of E-cadherin, the reduction of matrix metalloproteinase (MMP) and Slug protein expression, and inhibition of the production of reactive oxygen species (ROS). Furthermore, evidence is emerging that shows that ROS induced by radiation could increase Met activation. Following on these reports of SAC and Met, we investigated whether SAC could suppress Met activation. Materials and Methods: Wound healing, invasion, 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium (MTT), soft agar colony forming, western blotting, and gelatin zymography assays were performed in the human nasopharyngeal cancer cell lines HNE1 and HONE1 treated with SAC (0, 10, 20, or 40 mM) and hepatocyte growth factor (HGF). Results: This study showed that SAC could suppress the migration and invasion of HNE1 and HONE1 cell lines by inhibiting p-Met. An increase of migration and invasion induced by HGF and its decrease in a dose dependent manner by SAC in wound healing and invasion assays was observed. The reduction of p-Met by SAC was positively correlated with p-focal adhesion kinase (p-FAK) and p-extracellular related kinase (p-ERK in both cell lines). SAC reduced Slug, MMP2, and MMP9 involved in migration and invasion with the inhibition of Met-FAK signaling. Conclusion: These results suggest that SAC inhibited not only Met activation but also the downstream FAK, Slug, and MMP expression. Finally, SAC may be a potent anticancer compound for nasopharyngeal cancer treated with radiotherapy.

• Journal of Physiology & Pathology in Korean Medicine
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• v.27 no.6
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• pp.764-770
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• 2013

Stevia rebaudiana is a traditional herb used as a sweetener in Brazil and Paraguay as well as Korea and China. This study investigated the efficacy of Stevia rebaudiana methanol extract (SRE) to protect cells against the mitochondrial dysfunction and apoptosis in hepatocyte. To determine the effects of SRE on oxidative stress, we used the human derived hepatocyte cell line, HepG2 cell. Treatment of arachidonic acid (AA)+iron in HepG2 cells synergistically amplified cytotoxicity, as indicated by the excess reactive oxygen species (ROS) and mitochondrial permeability transition by fluorescence activated cell sorter (FACS) and immunoblot analysis. Treatment with SRE protected hepatocytes from AA+iron-induced cellular toxicity, as shown by alterations in the protein levels related with cell viability such as procaspase-3. SRE also prevented the mitochondrial dysfunction induced by AA+iron, and showed anti-oxidant effects as inhibition of $H_2O_2$ production and GSH depletion. Moreover, we measured the effects of SRE on AMP-activated protein kinase (AMPK), a key regulator in determining cell survival or death. Acetyl-CoA Carboxylase (ACC), a direct downstream target of AMPK. SRE increased phosphorylation of ACC, and prevented the inhibition of ACC phosphorylation by AA+iron. These results indicated that SRE has the ability to protect cells against AA+iron-induced $H_2O_2$ production and mitochondrial impairment, which may be mediated with AMPK-ACC pathway.

• BMB Reports
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• v.53 no.3
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• pp.148-153
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• 2020

Erythropoietin and iron have individually shown beneficial effects on early-phase liver regeneration following partial hepatectomy (PHx); however, there are limited data on the combined effect on late-phase liver regeneration after PHx. Here we examined combined effects of recombinant human erythropoietin (rhEPO, 3,000 IU/kg) and iron isomaltoside (IIM, 40 mg/kg) on late-phase liver regeneration following PHx and investigated the possible underlying mechanism. Rats administrated with rhEPO showed significantly higher liver mass restoration, interleukin-6 (IL-6, a hepatocyte mitogen) levels, and Ki-67-positive hepatocytes on day 7 after PHx than saline-treated controls. These beneficial effects were further enhanced on days 7 and 14 by co-treatment with IIM. This combination also significantly improved liver function indices, such as increased albumin production and decreased bilirubin levels, but did not alter serum levels of toxic parameters, such as aspartate transaminase and alanine transaminase. This study demonstrates that the combination of rhEPO and IIM synergistically improves late-phase liver regeneration and function after PHx, probably by promoting IL-6-mediated hepatocyte proliferation without adverse effects. Thus, this combination treatment can be a potential therapeutic strategy for patients undergoing resection for hepatic malignancies.

• Journal of Physiology & Pathology in Korean Medicine
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• v.24 no.6
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• pp.956-961
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• 2010

Tumor necrosis factor-alpha (TNF-${\alpha}$) is a major mediator of immuno-inflammatory activity. The purpose of this study is to investigate whether TNF-${\alpha}$ productions of mouse macrophage RAW 264.7 and human hepatocyte HepG2 are modulated by Artemisiae argi Folium water extract (AW), Lactobacillus pentosus-fermented Artemisiae argi Folium water extract (AFL), and Saccharomyces cerevisiae-fermented Artemisiae argi Folium water extract (AFS) for 3 h of incubation. Effect of AW on cell viability of HepG2 was also investigated. TNF-${\alpha}$ productions were measured by Enzyme-Linked Immnunosorbent Assay method and cell viability was measured by MTT assay. Both AFL and AFS significantly increased TNF-${\alpha}$ productions of RAW 264.7 at the concentration of 50, 100, and 200 ${\mu}g$/mL (p<0.05). Also, AFL and AFS significantly increased TNF-${\alpha}$ productions of HepG2 at the concentration of 50, 100, and 200 ${\mu}g$/mL (p<0.05). AW significantly increased TNF-${\alpha}$ production of HepG2 at the concentration of 100 and 200 ${\mu}g$/mL (p<0.05). AW did not show any cytotoxicity on HepG2 cells for 3 h. These results suggest that AFL, AFS, and AW have the immune-enhancing property related with its increasing effect on TNF-${\alpha}$ production of macrophage and hepatocyte.

• The Korean Journal of Physiology and Pharmacology
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• v.7 no.5
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• pp.261-266
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• 2003

Type 1 diabetes is an organ-specific autoimmune disease caused by the cytotoxic T cells-mediated destruction of the insulin-producing beta cells in the Langerhans pancreatic islets. Hepatocyte growth factor (HGF) is a potent mitogen and a promoter of proliferation of insulin producing beta cells of pancreatic islets. To study the role of HGF via viral vector in the development of streptozotocin (STZ)-induced diabetes in mice, we have developed an adenoviral vector genetically engineered to carry the gene for human HGF (hHGF) and evaluate the change of blood glucose, insulin level, and insulin-secreting beta cells of pancreatic islets. We demonstrate that the treatment with hHGF gene prevented the development of STZ-induced diabetes and increased serum insulin level to above normal range. Furthermore, it preserved pancreatic beta cells from destruction. These in vivo results may support previous findings that HGF is insulinotropic agent for beta cells and HGF treatment renders the cells to be resistant to the development of diabetes from STZ administration. We suggest that an adenoviral mediated hHGF gene therapy is a good candidate for the prevention and treatment of type 1 diabetes.

• Molecules and Cells
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• v.46 no.11
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• pp.688-699
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• 2023

We set up this study to understand the underlying mechanisms of reduced ceramides on immune cells in acute rejection (AR). The concentrations of ceramides and sphingomyelins were measured in the sera from hepatic transplant patients, skin graft mice and hepatocyte transplant mice by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). Serum concentrations of C24 ceramide, C24:1 ceramide, C16:0 sphingomyelin, and C18:1 sphingomyelin were lower in liver transplantation (LT) recipients with than without AR. Comparisons with the results of LT patients with infection and cardiac transplant patients with cardiac allograft vasculopathy in humans and in mouse skin graft and hepatocyte transplant models suggested that the reduced C24 and C24:1 ceramides were specifically involved in AR. A ceramide synthase inhibitor, fumonisin B₁ exacerbated allogeneic immune responses in vitro and in vivo, and reduced tolerogenic dendritic cells (tDCs), while increased P3-like plasmacytoid DCs (pDCs) in the draining lymph nodes from allogeneic skin graft mice. The results of mixed lymphocyte reactions with ceranib-2, an inhibitor of ceramidase, and C24 ceramide also support that increasing ceramide concentrations could benefit transplant recipients with AR. The results suggest increasing ceramides as novel therapeutic target for AR, where reduced ceramides were associated with the changes in DC subsets, in particular tDCs.