• YAKHAK HOEJI
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• v.58 no.4
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• pp.255-261
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• 2014

Poly-pharmacy has been on the rise because of aging of population and chronic disease. Most of drug metabolism happens in the liver by CYP isozymes and the metabolism by CYP450 enzymes. The Cytochrome P450 (CYP) is a superfamily of enzymes that catalyzes the oxidations of many endogenous and exogenous compounds. Primary human Hepatocytes (HH) are considered as the gold standard model for In vitro drug interaction studies. However, there are several limitations (cost, limited life span) for using HH cells. HepaRG cells are being used as a possible alternative. HepaRG cells were cultured in William E medium containing the positive control inducers (1A2: 10, 25, 50 ${\mu}M$ omeprazole, 2C9 and 2C19: 10 ${\mu}M$ rifampin, 3A4: 10, 25, 50 ${\mu}M$ rifampin) at $37^{\circ}C$, 5 % $CO_2$ in a humidified atmosphere. This study was to evaluate the induction of CYP isozymes (1A2, 2C9, 2C19 and 3A4) using LC-MS/MS. We evaluated the potential induction ability of Bosentan, as a drug of pulmonary artery hypertension, in HepaRG cells. For reference, dose of the Bosentan is determined to the basis of the $C_{max}$ (835 mg/ml) value. The enzyme activity demonstrated that CYP2C9 and 3A4 were induced up to 20 times by Bosentan. Like as In vivo, the enzyme activity of CYP2C9 and CYP3A4 is significantly induced in a dose-dependent by Bosentan.

• Journal of Life Science
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• v.25 no.10
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• pp.1098-1102
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• 2015

FABPpm (plasma membrane-bound fatty acid binding protein ) is highly expressed in skeletal muscle. The principal role of this protein is modulating fatty acid uptake and metabolism. The influence of insulin-like growth factor-I (IGF-I), which is a major regulator of skeletal muscle cells, on FABPpm in skeletal muscle cells has not been investigated. To determine the effect of IGF-I on the expression of FABPpm, differentiated C2C12 murine skeletal muscle cells were treated with 20 ng/ml of IGF-I for different times. IGF-I increased the expression of FABPpm in a time-dependent manner. The mRNA level of FABPpm was measured by real-time quantitative PCR to determine whether the IGF-1-induced induction of FABPpm was regulated pretranslationally. The IGF-I treatment resulted in very rapid induction of the FABPpm mRNA transcript in the C2C12 myotubes. After 24 and 48 hr of the IGF-I treatment, FABPpm mRNA increased 130 and 179%, respectively. The increase in the protein expression returned to control levels after 72 hr of the IGF-I treatment, suggesting that IGF-1 regulated the FABPpm gene pretranslationally in skeletal muscle cells. This is the first evidence that IGF-I has a modulatory effect on the expression of FABPpm. In conclusion, IGF-I induced rapid transcriptional modification of the FABPpm gene in C2C12 skeletal muscle cells and exerted modulatory effects on FABPpm.

• Journal of Life Science
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• v.24 no.12
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• pp.1284-1290
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• 2014

Fatty acid transporter protein 1 (FATP1) is highly expressed in skeletal muscle and modulates fatty acid uptake and metabolism. However, the influence of insulin-like growth factor-I (IGF-I), a master regulator of skeletal muscle cells, on FATP1 in skeletal muscle cells has not been demonstrated. To investigate the effect of IGF-I on FATP1 and the expression of the IGFBP5 protein, differentiated C2C12 murine skeletal muscle cells were treated with 20 ng/ml of IGF-I at different time points. The results showed that IGF-I increased FATP1 and IGFBP5 protein expression in a time-dependent manner. To determine whether this induction of FATP1 by the IGF-I treatment was regulated pretranslationally, the mRNA level of FATP1 was measured by real-time quantitative PCR. The IGF-I treatment resulted in very rapid induction of the FATP1 mRNA transcript in C2C12 myotubes. FATP1 mRNA increased 169% and 132% after 24 and 48 h of the IGF-I treatment, respectively, and it returned to control levels after 72 h of the treatment, suggesting that the FATP1 gene is regulated pretranslationally by IGF-I in skeletal muscle cells. This is the first evidence that IGF-I can regulate the expression of FATP1. In conclusion, IGF-I induced rapid transcriptional modification of the FATP1 gene in C2C12 skeletal muscle cells and had modulating effects on fatty acid uptake proteins and oxidative proteins.

• YAKHAK HOEJI
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• v.29 no.1
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• pp.18-26
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• 1985

The present study was undertaken to investigate the possible effect of ginseng butanol fraction on the hepatic acetaldehyde metabolism. Experimental animals were used for the subject of the study. When, in case of mitochondrial aldehyde dehydrogenase (Ald DH), ginseng butanol fraction was added, enzyme activity was increased in a small dose, while, in a large dose, it showed inhibitory effect. In terms of kinetic aspect, ginseng butanol fraction has the effect to decrease the Km values of Ald DH. In vivo studies, the activity of Aid DH increased by induction of acute intoxication of ethanol was further increased through pretreatment with ginseng butanol fraction. When ginseng butanol fraction was given to mice fed with 5% ethanol instead of water for 60 days, the activity of Ald DH in mitochondrial fraction decreased to about 35% in chronic alcoholism, but after pretreatment of ginseng butanol fraction the activity was restored to the control level. By the pretreatment with disulfiram, the Ald DH activity was inhibited in normal and alcohol-treated groups, but after the treatment with ginseng butanol fraction the activity was restored to the control level. The results suggest that ginseng butanol fraction enhance the Ald DH activity inhibited by the treatment of disulfiram with no relation to NAD. It was observed that ginseng butanol fraction markedly decrease the acetaldehyde levels in plasma and liver. All these observations suggested that reduction of acetaldehyde in blood and liver should be dependent upon increased activity of mitochonclrial Ald DH. It is concluded that the recovery from alcohol intoxication should be prompted by treatment with ginseng.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.6
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• pp.827-835
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• 2009

Insulin has crucial roles in energy metabolism in all mammals but has been less studied in ruminants. An experiment was conducted to investigate the effects of hypoinsulinemia induction on appetite, performance, carcass composition and blood metabolite levels in sheep. Treatments were intravenous injection of four doses of streptozotocin; 0, 25, 50 and 75 mg/kg BW named C, L, M and H, respectively. Twenty male lambs were divided into four treatment groups. Animals in group H could not continue the experiment because of abnormalities. The duration of the experiment was eight consecutive weeks, and injection was performed at the end of week 3. Feed and water intakes were measured weekly and weight changes of animals were recorded and used for calculation of other growth parameters. Blood samples were collected weekly via venipuncture at fasting and 2.5 h post-prandial and analyzed for hormones and blood metabolites. Results showed a marked hypoinsulinemia in group M with significant decrease in fasted and postprandial insulin concentrations and also fasted leptin concentrations vs. the control group C (p<0.05). Group M showed significant increases in blood glucose, triglycerides, cholesterol, total protein, blood urea nitrogen and ketone body levels vs. group C (p<0.05). After injection, animals in group M showed diabetic hyperphagia and enhanced water intake as compared to group C (p<0.05) but, despite increased feed intake, they did not gain more weight than controls (p<0.05), and consequently, their feed conversion ratio was greater. Protein and fat contents of meat and liver were not significantly different among groups (p>0.05). In conclusion, the results suggested a regulatory role of insulin in energy metabolism of ruminants by exerting two opposing effects; central catabolic and peripheral anabolic.

• Proceedings of the KSAR Conference
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• 2003.06a
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• pp.78-78
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• 2003

Embryonic stem (ES) cells, derived from preimplantation embryo, are able to differentiate into various types of cells consisting the whole body, or pluripotency. In contrast, terminally differentiated cells do not usually alter their nature but frequently die or transform if they are exposed to inappropriate external stimulations. In addition to the plasticity, ES cells are expected to be different from terminally differentiated cells in very many ways, such as patterns of gene expressions, ability and response of the cells in confronting environmental stimulations, metabolism, and growth rate. As a model system to differentiate these two types of cells, human ES cells (MB03) and terminally differentiated cells (HeLa), we examined the ability of these two types of cells in confronting a severe oxidative insult, that is $H_2O$$_2$. Approximately 1$\times$10$^4$ cells were plated in 96 well plate and serum starved for overnight. The conditioned cells were exposed to a various concentration of $H_2O$$_2$ fur 24 hrs and loaded with neutral red (50$\mu\textrm{g}$/ml) for 4 hrs, washed with PBS for 2 min three times, and entrapped dye was dissolved out using acetic ethanol. Cytotoxicity was determined by reading the amount of dye in the medium using microplate reader. equipped with 575 nm filter. Relative amount of the dye entrapped within MB03 or HeLa were not significantly different when cells were exposed up to 0.4 mM $H_2O$$_2$. However, this sharply decreased down to 0.12% in HeLa cells when the cells were exposed to 0.8 mM $H_2O$$_2$, while it was approximately 54% in MB03 suggesting that this concentration of $H_2O$$_2$ is the defensive threshold for HeLa cells. The resistance to oxidative stimulation reversed, however, when cells were co-treated with BSO (L-buthionine- 〔S, R〕-sulfoximine) which chelates intracellular GSH. This result suggests that cellular GSH is the major defensive mechanism of human ES cells. Induction of enzymes involved in GSH metabolism and type of cell death is currently being studied.

• Proceedings of the Korean Society of Crop Science Conference
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• 2007.04a
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• pp.65-73
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• 2007

The objective of this study is to understand how regulatory mechanisms respond to sugar status for more efficient carbon utilization and source-sink regulation in plants. So, we need to identify and characterize many components of sugar-response pathways for a better understanding of sugar responses. For this end, genes responding change of sugar status were screened using Arabidpsis cDNA arrays, and confirmed thirty-six genes to be regulated by sucrose supply in detached leaves by RNA blot analysis. Eleven of them encoding proteins for amino acid metabolism and carbohydrate metabolism were repressed by sugars. The remaining genes induced by sugar supply were for protein synthesis including ribosomal proteins and elongation factors. Among them, I focused on three hydrolase genes encoding putative $\beta$-galactosidase, $\beta$-xylosidase, and $\beta$-glucosidase that were transcriptionally induced in sugar starvation. Homology search indicated that these enzymes were involved in hydrolysis of cell wall polysaccharides. In addition to my results, recent transcriptome analysis suggested multiple genes for cell wall degradation were induced by sugar starvation. Thus, I hypothesized that enzyme for cell wall degradation were synthesized and secreted to hydrolyze cell wall polysaccharides producing carbon source under sugar-starved conditions. In fact, the enzymatic activities of these three enzymes increased in culture medium of Arabidopsis suspension cells under sugar starvation. The $\beta$-galactosidase encoded by At5g56870 was identified as a secretory protein in culture medium of suspension cells by mass spectrometry analysis. This protein was specifically detected under sugar-starved condition with a specific antibody. Induction of these genes was repressed in suspension cells grown with galactose, xylose and glucose as well as with sucrose. In planta, expression of the genes and protein accumulation were detected when photosynthesis was inhibited. Glycosyl hydrolase activity against galactan also increased during sugar starvation. Further, contents of cell wall polysaccharides especially pectin and hemicellulose were markedly decreased associating with sugar starvation in detached leaves. The amount of monosaccharide in pectin and hemicellulose in detached leaves decreased in response to sugar starvation. These results supported my idea that cell wall has one of function to supply carbon source in addition to determination of cell shape and physical support of plant bodies.

• Journal of the Korean Society of Tobacco Science
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• v.20 no.1
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• pp.99-107
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• 1998

Numerous studies have demonstrated a negative association between cigarette smoking and Parkinson's disease. The present study was undertaken to investigate whether chronic exposure of mice to cigarette smoke a(footed the metabolism of 1-methyl-1113,6-tetrahydro-pyridine (MPTP) by cytochrome P4SO (P-450) or flavin-containing monooxygenase (FMO) in the hepatic microsomes of C57BL6/J mice. Adult male C57BL6/J mice were exposed to mainstream smoke generated from 15 cigarettes for 10 min a day and 5 day per week for 6 weeks. MPTP (10 mg/kg body weight) was administered to mice by subcutaneous injection for 6 consecutive days. Microsolnal P-450 content was increased by MPTP, smoke exposure, or both, but NADPH cytochrome P-450 reductase activity was rather decreased by the same treatments. The activities of benzo(a)pyrene hydroxylase, 7-ethoxycoumarin O-deethylase and ethoxyresorufin O-deethylase were significantly increased by the exposure of cigarette smoke, but were not or little affected by MPTP treatment. Benzphetamine N-demethylase activity was not affected either by MPTP treatment or by cigarette smoke exposure, but it was significantly increased by the combined MPTP treatment with cigarette smoke exposure, showing their synergic effect for the induction of the enzyme activity. Interestingly, in vitro studies of hepatic FMO and P-450 system both O-oxygenation and N-demethylation of MPTP were increased in the smoke-exposed or in the MPTP-treated mice. These results suggest that the enhancement in the N-demethylation as well as O-deethylation of P-450 system and in the N-oxygenation of FMO activity by cigarette smoke exposure in mouse liver may contribute to attenuating the neurotoxic effects of MPTP on the nigrostriatal dopaminergic neurons.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.13
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• pp.5471-5476
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• 2015

2-deoxy-D-Glucose (2DG) causes cytotoxicity in cancer cells by disrupting thiol metabolism. It is an effective component in therapeutic strategies. It targets the metabolism of cancer cells with glycolysis inhibitory activity. On the other hand, MLN4924, a newly discovered investigational small molecule inhibitor of NAE (NEDD8 activating enzyme), inactivates SCF E3 ligase and causes accumulation of its substrates which triggers apoptosis. Combination of these components might provide a more efficient approach to treatment. In this research, 2DG and MLN4924 were co-applied to breast cancer cells (MCF-7 and SKBR-3) and cytotoxic and apoptotic activity were evaluated the by Micro culture tetrazolium test (MTT), TUNEL and ELISA methods. Caspase3 and Bcl2 genes expression were evaluated by real time Q-PCR methods. The results showed that MLN4924 and MLN4924/2DG dose-dependently suppressed the proliferation of MCF7 and SKBR-3 cells. Cell survival of breast cancer cells exposed to the combination of 2DG/MLN4924 was decreased significantly compared to controls (p<0.05), while 2DG and MLN4924 alone had less pronounced effects on the cells. The obtained results suggest that 2DG/MLN4924 is much more efficient in breast cancer cell lines with enhanced cytotoxicity via inducing a apoptosis cell signaling gene, caspase-3.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.1
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• pp.9-21
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• 2015

Cancer, a serious public health problem in worldwide, results from an excessive and uncontrolled proliferation of the body cells without obvious physiological demands of organs. The gastrointestinal tract, including the esophagus, stomach and intestine, is a unique organ system. It has the highest cancer incidence and cancer-related mortality in the body and is influenceed by both genetic and environmental factors. Among the various chemical elements recognized in the nature, some of them including zinc, iron, cobalt, and copper have essential roles in the various biochemical and physiological processes, but only at low levels and others such as cadmium, lead, mercury, arsenic, and nickel are considered as threats for human health especially with chronic exposure at high levels. Cadmium, an environment contaminant, cannot be destroyed in nature. Through impairment of vitamin D metabolism in the kidney it causes nephrotoxicity and subsequently bone metabolism impairment and fragility. The major mechanisms involved in cadmium carcinogenesis could be related to the suppression of gene expression, inhibition of DNA damage repair, inhibition of apoptosis, and induction of oxidative stress. In addition, cadmium may act through aberrant DNA methylation. Cadmium affects multiple cellular processes, including signal transduction pathways, cell proliferation, differentiation, and apoptosis. Down-regulation of methyltransferases enzymes and reduction of DNA methylation have been stated as epigenetic effects of cadmium. Furthermore, increasing intracellular free calcium ion levels induces neuronal apoptosis in addition to other deleterious influence on the stability of the genome.