• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.74.2-74
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• 2003

Arabidopsis infected with beet curly top virus (BCTV) has the systemic symptoms like stunting of Plant growth, curling of leaves and shoot tips, and callus induction. The regulation of sucrose metabolism by BCTV infection is essential for obtaining the energy source in the process of virus replication and symptom development. Sucrose metabolism-associated gene expression and biochemical enzyme activity were analyzed with the rossette leaves and inflorescencestems of BCTV infected Arabidopsis by the time course of 1, 7, 14, 21 day postinoculation. The expression of invertase and sucrose synthase genes ( encoding sucrose-cleaving enzymes )was increased and reversely the level of Atkin10a ( sucrose non-fermenting gene ) was decreased, resulting by semi-quantitative reverse transcription polymerase chain reaction. The biochemical analysis of invertase and sucrose synthase activity was performed. The activity of neutral invertase in the inflorescence stems was elevated remarkably. The photosynthetic response in the source of sucrose metabolism was consistent with the down-regulation of ribulose 1,5 bisphosphate carboxylase gene, and lower activity than mock-inoculated plants. The levels of genes pertaining to the cell cycle, hormone, and biotic stress-related pathway showed an increase or a decrease dependent on viral symptoms. Therefore, sucrose sensing by BCTV infection can regulate the expression of sucrose metabolism-related key enzymes such as invertase and Atkin10a, and these gene products might influence to symptom development.

• Archives of Pharmacal Research
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• v.18 no.4
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• pp.262-266
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• 1995

Bacterial lipopolysaccharide (LPS) is one of the most potent inducers of various cytokines nad other proinflammatory mediators in macrophages. Although pathophysiological consequences of LPS-induced responses are well established, the mechanisms through which LPS-generated singals are transduced remain unclear. In the present study, we attempted to determine early intracellular events after LPS binding which transduced the signal for the induction of arachidonic acid metabolism in rat alveolar macrophages. While H-7, a protein kinase C(PKC) inhibitor, did not affect LPS-stimulated prostaglandin synthesis, staurosporine enhanced archidonic acid etabolism in macropahages treated with LPS. Phorbol-12-myristate-13 acetate snesitive to LPS compare with control group. PMA and H-7 did not alter the effect of flucose. Pertussis toxin did not show nay effect, thus pertussis toxin snesitive G-protein pathway appears not to play a role in this experimental system. Genistein and tyrphostin 25, protein tyrosine kinase 9PTK) inhibitors, markedly inhibited prostaglandin synthesis in macrophages nal transduction events leading to icnreased macrophage arachidonic acid metabolism.

• Horticultural Science & Technology
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• v.19 no.3
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• pp.315-319
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• 2001

The study was carried out to develop a simple and efficient system to regenerate plants from cotyledon and hypocotyl tissues of Chinese cabbage (Brassica campestris L. ssp. pekinensis cv Seoul). Among the various combinations of naphthalene acetic acid (NAA) and 6-benzyladenine (BA) tested, the best shoot induction medium for cotyledon, with 2.67 shoots per explants, contained $2.0mg{\cdot}L^{-1}$ NAA, $1.0mg{\cdot}L^{-1}$ BA and $16.7mg{\cdot}L^{-1}$ $AgNO_3$. The shoot induction medium with $1.0mg{\cdot}L^{-1}$ NAA, $5.0mg{\cdot}L^{-1}$ BA and $16.7mg{\cdot}L^{-1}$ $AgNO_3$, was best for shoot induction from hypocotyl explants, with 1.87 shoots per explants. After shoot induction, regenerated shoots were excised and rooted on rooting medium. Rooted plantlets were then hardened in the high humidity growth chamber and transplanted to pots, and then grown in the greenhouse. Regenerated plants appeared phenotypically normal and there were no changes in chromosome number.

• Korean Journal of Ecology and Environment
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• v.44 no.4
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• pp.364-372
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• 2011

The pale chub (Zacco platypus) is generally found in Asian countries, such as Korea, Japan, and China. Nevertheless, very little information exists about the genes involved in the metabolism of xenobiotics in this species. This species is useful in monitoring the environmental impact on various pollutants in freshwater as a sentinel fish species. We cloned the full-length cDNA sequence of xenobiotic metabolizing cytochrome P450 1A (CYP1A) gene from Z. platypus and characterized it. Tissue distribution and timedependent induction of CYP1A were studied by real-time RT-PCR. Induction pattern of CYP1A was studied by exposing the fish to an arylhydrocarbon receptor agonist, ${\beta}$-naphthoflavone (BNF). The liver showed the highest level of expression in basal state as well as BNF- treated fish. However, appreciable levels of expression were also recorded in Gill and kidney and the least level of expression was observed in the eye. The results of the time-course study revealed an induction in the liver, brain, and gills after 6 h and 12 h in most of the tissues. This study provides an insight into the xenobiotics metabolizing system of Z. platypus and offers baseline information for further research related to biomarker, stress, and adaptive response of this ecologically important fish species in the freshwater environment.

• Biomolecules & Therapeutics
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• v.23 no.5
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• pp.486-492
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• 2015

Drug metabolism mostly occurs in the liver. Cytochrome P450 (CYP) is a drug-metabolizing enzyme that is responsible for many important drug metabolism reactions. Recently, the US FDA and EU EMA have suggested that CYP enzyme induction can be measured by both enzymatic activity and mRNA expression. However, these experiments are time-consuming and their interassay variability can lead to misinterpretations of the results. To resolve these problems and establish a more powerful method to measure CYP induction, we determined CYP induction by using luminescent assay. Luminescent CYP assays link CYP enzyme activity to firefly luciferase luminescence technology. In this study, we measured the induction of CYP isozymes (1A2, 2B6, 2C9, and 3A4) in cryopreserved human hepatocytes (HMC424, 478, and 493) using a luminometer. We then examined the potential induction abilities (unknown so far) of mesalazine, a drug for colitis, and mosapride citrate, which is used as an antispasmodic drug. The results showed that mesalazine promotes CYP2B6 and 3A4 activities, while mosapride citrate promotes CYP1A2, 2B6, and 3A4 activities. Luminescent CYP assays offer rapid and safe advantages over LC-MS/MS and qRT-PCR methods. Furthermore, luminescent CYP assays decrease the interference between the optical properties of the test compound and the CYP substrates. Therefore, luminescent CYP assays are less labor intensive, rapid, and can be used as robust tools for high-throughput CYP screening during early drug discovery.

• Molecules and Cells
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• v.28 no.3
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• pp.201-207
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• 2009

Silibinin is a polyphenolic flavonoid compound isolated from milk thistle (Silybum marianum), with known hepatoprotective, anticarcinogenic, and antioxidant effects. Herein, we show that silibinin inhibits receptor activator of $NF-{\kappa}B$ ligand (RANKL)-induced osteoclastogenesis from RAW264.7 cells as well as from bone marrow-derived monocyte/macrophage cells in a dose-dependent manner. Silibinin has no effect on the expression of RANKL or the soluble RANKL decoy receptor osteoprotegerin (OPG) in osteoblasts. However, we demonstrate that silibinin can block the activation of $NF-{\kappa}B$, c-Jun N-terminal kinase (JNK), p38 mitogen-activated protein (MAP) kinase, and extracellular signal-regulated kinase (ERK) in osteoclast precursors in response to RANKL. Furthermore, silibinin attenuates the induction of nuclear factor of activated T cells (NFAT) c1 and osteoclast-associated receptor (OSCAR) expression during RANKL-induced osteoclastogenesis. We demonstrate that silibinin can inhibit $TNF-{\alpha}$-induced osteoclastogenesis as well as the expression of NFATc1 and OSCAR. Taken together, our results indicate that silibinin has the potential to inhibit osteoclast formation by attenuating the downstream signaling cascades associated with RANKL and $TNF-{\alpha}$.

• Journal of Physiology & Pathology in Korean Medicine
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• v.27 no.2
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• pp.196-201
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• 2013

Abnormal regulation of glucose and impaired lipid metabolism that result from a defective or deficient insulin are the key etiological factor in type 2 diabetes mellitus (T2DM). The our study evaluated the beneficial effect of diet supplementation with Lentinus edodes on hyperglycemia and lipid metabolism in normal and type 2 diabetic rats. The animals were divided into 4 groups: group I(control) rats were fed standard diet (12% of calories as fat); group II (T2DM) rats were fed HFD (40% of calories as fat) for 2 weeks and then injected with STZ (50 mg/kg); group III and group IV rats were continually fed a diet containing 1% and 10% Lentinus edodes for 4 weeks after T2DM induction, respectively. After 4 weeks we determined biochemical parameters such as glucose, insulin concentration, serum total cholesterol (TC), triglycerides (TG), high-density lipoprotein (HDL), and glycosylated hemoglobin (HbA1c) concentration were also measured. There was a significant reduction in serum TC and TG in the Lentinus edodes supplement groups. The Lentinus edodes diet supplementation were found to have a potent lipid metabolism improvement as well as LDL concentration decreased and HDL concentration was increased. Concentrations of blood glucose and HbA1c in the experimental groups II were significantly decreased after 4 weeks compared with the control group. The Lentinus edodes diet supplementation is useful in regulating the glucose level, improves the insulin, HbA1c, serum lipid metabolism in experimental diabetic rats. We suggest that Lentinus edodes supplementation may have the control effects of diabetes mellitus by improving blood glucose control and lipid metabolism.

• Biomedical Science Letters
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• v.7 no.3
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• pp.111-116
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• 2001

To investigate an effect of aging on the xylene metabolism in liver damaged animals, a study was conducted. 50% carbon tetrachloride ($CCl_4$) in olive oil (0.1 ml/100 g body weight) was intraperitoneally given to 5-week and 12-week rats 12 times every other day and then one dose of 50% xylene in olive oil (0.25 ml/100 g body weight) was intraperitoneally given to the rats, and after 24 hr, the animals were sacrificed. On the basis of the functional findings in rat liver, ie, serum levels of alanine aminotransferase activity, liver protein and malonedialdehyde contents, 5-week rats showed less liver damage than 12-week rats. The increasing rate of urinary methylhippuric acid concentration to the control was significantly higher in 5-week rats than 12-week rats in case of xylene treatment after induction of liver damage. On the other hand, liver damaged 5-week rats showed significant rise of hepatic cytochrome P45O content compared with the liver damaged 12-week rats by the xylene treatment. And increasing rate of hepatic alcohol or aldehyde dehydrogenase activities to each liver damaged animals was higher tendency in 5-week rats than 12-week rats by the xylene treatment. In conclusion, 5-week rat showed greater metabolic rate of xylene than 10-week rats in case of liver injury because 5-week rats led to a slight liver damaged compared with 12-week rats.

• Journal of the Korean Society of Food Science and Nutrition
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• v.19 no.5
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• pp.403-410
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• 1990

The effect of ascorbic acid (AsA) or kimchi on the metabolism of xenobiotics in guinea pig administered policyclic aromatic hydrocarbons(PAH) an environmental pollutant was inves-tigated. Guinea pigs given oral supplementation were divided into 4 groups. Group A(control) was supplemented with 2mg of AsA/day group B with 2mg of AsA and PAH/day gruop C with 50mg of AsA and PAH/day. Changes of liver cytochrome P-450 contents and 7-ethoxycou-marin O-deethylase(ECOD) activity glutamate-oxaloacetate transferase(GOT) activity in serum and AsA contents in various tissues were determined. Cytochrome P-450 contents ECOD activity and GOT activity increased in B, C and D groups administered PAH. Moreover cytoch-rome P=450 contents and ECOD activity in group C were higher than those of group A and D. The content of AsA in the tissues of group B was lower than that of A, C and D groups respectively. These results suggested that AsA was necessary in the PAH metabolism moreo-ver supplementation of large amount of AsA or kimchi in the guinea administered PAH had an influence in the drug-metabolizing enzyme induction thus caused a decrease of AsA in tissues.

• Proceedings of the Korean Nuclear Society Conference
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• 2005.05a
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• pp.1008-1009
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• 2005

In order to screen ionizing radiation induced early-response genes, we employed subtractive hybridization method and isolated a metabolism associated gene. The gene expression was very sensitive to ionizing radiation as revealed by a rapid induction of its messenger RNA. We characterized the function of this gene in radiation response. This gene activated p53 and enhanced cell killing effect of ionizing radiation. This effect was attributable to p53 phosphorylation and transcriptional activation.