• Journal of Sericultural and Entomological Science
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• v.39 no.2
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• pp.119-133
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• 1997

Isozyme was used to characterize general protein patterns of genetic relationships among 303 silkworm stocks preserved in National Sericultural and Entomology Research Institute, RDA. Six isozymes (esterase, acid phosphatase, alkaline phosphatase, amylase, glucose-6-phosphate dehydrogenase and sucrase) from hemolymph, midgut, and digestive juice were employed to construct dendograms(UPGMA method) using a polycrylamide gel electrophoresis. A cluster analysis revealed four major group, which were divided into several subgroups within each group, contained assemglages of Japanese and Chinese races. Especially, genetic differentiation in the first and second group was greatest rather than within Japanese and Chinese races repectively and was concordant with the hypothesis of phyletic sorting of initial variability in China many years ago. Hypothesized recent introgression between groups was also plausible, but the eviednce suggested bidirectional gene flow between the Chinese and the Japnaese lineages. Interpreting the results in light of evidence from the current study, the genetic diversity and relationship showed in Korean silkworm race, Hansammyun reflected early and independent evolution from the Chinese ancestor, limited addition of new variability and phyletic sorting within Korean peninsula more than 4,000 years.

• Proceedings of the Korean Journal of Food and Nutrition Conference
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• 2000.05a
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• pp.13-20
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• 2000

Melatonin, a chemical mediator produced in the mammalian pineal gland and several other organ, is a ubiquitously acting antioxidant. It has been shown to scavenge the hydroxyl radical (ㆍOH), singlet oxygen ($^1$O$_2$) and the peroxynitrite anion (ONOO-). In addition, melatonin reportedly stimulates a number of antioxidative enzymes including glutathione peroxidase, glutathione reductase and glucose-6-phosphate dehydrogenase. Antioxidative effect of melatonin in pharmacological and physiological level was investigated using hepatocarcinogen 2-nitropropane (2-NP) and pinealectornized (Px) rats, respectively. Lipid peroxidation (LPO) as indicated by malondialdehyde and 4-hydroxyalkenals and DNA damage as indicated by 8-hydroxydeoxyguanosine (8-OH-dG) induced by 2-NP were prevented by melatonin. The degree of LPO and DNA damage in Px rats were higher than those of intact old and young ones suggesting the removal of pineal gland resulted in higher accumulation of oxidative damage.

• Proceedings of the PSK Conference
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• 2001.10a
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• pp.178.2-178.2
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• 2001

• Journal of Food Hygiene and Safety
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• v.28 no.2
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• pp.89-94
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• 2013

The present study was undertaken to elucidate the mechanisms underlying the cholesterol-lowering effect of S-allylmercaptocysteine (SAMC) derived from aged garlic. Rat hepotocytes and HepG2 cells were used to determine the short-term effects of SAMC on [$^{14}C$] acetate incorporation into cholesterol, and several enzymatic steps. The cells were grown in Dulbecco's modified Eagle's medium supplemented with 10% fetal bovine serum and treated with 20, 40, 60 and 80 ${\mu}g/ml$ of SAMC. At concentration of 20~40 ${\mu}g/ml$, no significant cells viability effect was noted during those incubation periods. However, at a concentration 60 ${\mu}g/ml$, cell viability decreased approximately 50% compared with the control. The treatment of cells with 5, 10, 15, and 20 ${\mu}g/ml$ of SAMC resulted in a marked of [$^{14}C$]-acetate incorporation into cholesterol. At concentration of 15 ${\mu}g/ml$, the cholesterol synthesis was inhibited 79% in cells. The activities of lipogenic enzymes, fatty acid synthase (FAS), and glucose-6-phosphate dehydrogenase (G3PDH) were measured in culture hepatocytes treated with the inhibitors. The activity of FAS in cells treated with 0.95 nmol SAMC was 19% lower than that of nontreated cells, and no affected G6PDH activity, 3-hydroxy-3-methylglutaryl Co A activity was decreased at concentration dependant manner. The present study demonstrates that SAMC is effective in inhibiting cholesterol biosynthesis.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.4
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• pp.537-547
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• 2018

Objective: This study was performed to understand transcriptional changes in the genes involved in gluconeogenesis and glycolysis pathways following castration of bulls. Methods: Twenty Korean bulls were weaned at average 3 months of age, and castrated at 6 months. Liver tissues were collected from bulls (n = 10) and steers (n = 10) of Korean cattle, and hepatic gene expression levels were measured using quantitative real-time polymerase chain reaction. We examined hepatic transcription levels of genes encoding enzymes for irreversible reactions in both gluconeogenesis and glycolysis as well as genes encoding enzymes for the utilization of several glucogenic substrates. Correlations between hepatic gene expression and carcass characteristics were performed to understand their associations. Results: Castration increased the mRNA (3.6 fold; p<0.01) and protein levels (1.4 fold; p<0.05) of pyruvate carboxylase and mitochondrial phosphoenolpyruvate carboxykinase genes (1.7 fold; p<0.05). Hepatic mRNA levels of genes encoding the glycolysis enzymes were not changed by castration. Castration increased mRNA levels of both lactate dehydrogenase A (1.5 fold; p<0.05) and lactate dehydrogenase B (2.2 fold; p<0.01) genes for lactate utilization. Castration increased mRNA levels of glycerol kinase (2.7 fold; p<0.05) and glycerol-3-phosphate dehydrogenase 1 (1.5 fold; p<0.05) genes for glycerol utilization. Castration also increased mRNA levels of propionyl-CoA carboxylase beta (mitochondrial) (3.5 fold; p<0.01) and acyl-CoA synthetase short chain family member 3 (1.3 fold; p = 0.06) genes for propionate incorporation. Conclusion: Castration increases transcription levels of critical genes coding for enzymes involved in irreversible gluconeogenesis reactions from pyruvate to glucose and enzymes responsible for incorporation of glucogenic substrates including lactate, glycerol, and propionate. Hepatic gluconeogenic gene expression levels were associated with intramuscular fat deposition.

• Journal of Microbiology and Biotechnology
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• v.20 no.6
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• pp.978-984
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• 2010

This paper examines the probiotic bacterium Lactobacillus rhamnosus GG, and how it reacts to the presence of mucin in its extracellular milieu. Parameters studied included cell clustering, adhesion to mucin, extracellular protein production, and formation of final metabolites. L. rhamnosus GG was found to grow efficiently in the presence of glucose, N-acetylglucosamine, or mucin (partially purified or purified) as sole carbon sources. However, it was unable to grow using other mucin constituents, such as fucose or glucuronic acid. Mucin induced noticeable changes in all the parameters studied when compared with growth using glucose, including in the formation of cell clusters, which were easily disorganized with trypsin. Mucin increased adhesion of the bacterium, and modulated the production of extracellular proteins. SDS-PAGE revealed that mucin was not degraded during L. rhamnosus GG growth, suggesting that this bacterium is able to partially use the glucidic moiety of glycoprotein. This study goes some way towards developing an understanding of the metabolic and physiological changes that L. rhamnosus GG undergoes within the human gastrointestinal tract.

• Environmental Analysis Health and Toxicology
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• v.24 no.1
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• pp.53-61
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• 2009

사람 기관지상피세포주인 BEAS-2B에 담배연기농축액(CSC)을 처리하여 유도된 1198 세포주는 대조군 세포주인 1799에 비해 현저하게 낮은 glutathione 농도와 낮은 glutamate-cysteine ligase(GCL), glutathione peroxidase(GPx), glucose-6-phosphate dehydrogenase(G6PD), catalase 효소활성을 보였다. 두 세포주를 포도당 존재 하에서 4시간 hypoxia 처리 후 reoxygenation 하면서 시간에 따른 세포의 항산화계 활성을 측정한 결과, 1799 세포주에서는 의미 있는 변화가 관찰되지 않은 반면, 1198 세포주에서는 hypoxia 처리에 의해 glutathione의 농도 및 GSH/GSSG 비와 G6PD 활성이 감소되었고, reoxygenation 기에는 GPx, glutathione reductase(GRd), G6PD, superoxide dismutase 활성이 감소되었다. 그러나 reoxygenation 2시간 이후에는 GRd와 G6PD 활성의 회복이 관찰되었으며, 그 결과 GSH/GSSG 비율이 회복되었다. 이 실험 결과는 CSC가 능력을 현저히 저하시킬 수 있음을 보여준다. Glutathione은 hypoxia-reoxygenation에 의한 산화적 스트레스 하에서 항산화제로서의 역할뿐 아니라, 세포 내 GSH/GSSG 비의 변화를 통해 산화적 스트레스에 대한 항산화계의 적응 반응 여부를 결정하는 중요한 인자로 작용할 것으로 보여진다.

• Toxicological Research
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• v.35 no.3
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• pp.249-255
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• 2019

Cadmium is a strong toxic heavy metal which presents in paints and liquid wastes and causes oxidative stress in fish. On the other hand, lead is widely used for different purposes, e.g. lead pipes, it targets vital organs such as liver and kidney causing biochemical alterations. The present study evaluates the effects of 60 days exposure to Cd and Pb either single or combined together in African catfish. Sixty-four fishes were divided into 3 groups and exposed to $CdCl_2$ (7.02 mg/L) or $PbCl_2$ (69.3 mg/L) or a combination of them along with control group. Activities of acid phosphatase (ACP), lactate dehydrogenase (LDH) and glucose-6-phosphate dehydrogenase (G-6-PDH) were estimated. Moreover, gill, liver and kidney were assayed for activities of superoxide dismutase (SOD), catalase (CAT) and levels of glutathione (GSH) and malondialdehyde (MDA). Individual exposure showed that both Cd and Pb significantly decreased LDH activity and SOD activity in the kidney. Pb significantly increased G-6-PDH activity and decreased GSH level in the gill. CAT activity in liver and kidney elevated significantly on Cd exposure while lead caused a significant depletion in the liver and significant elevation in the kidney. Both Cd and Pb significantly increased MDA levels in liver and kidney while Pb increased its level in gills. The combined exposure resulted in normalization of LDH, G-6-PDH activity, and CAT activity in liver and kidney as well as GSH level in both tissues and MDA in gill and kidney. The combination increased SOD activity and MDA level in liver and decreased SOD activity in kidney and GSH level in gills. In conclusion, the antioxidant system of African catfish was adversely affected by prolonged exposure to Cd and Pb. The combined exposure caused less damage than individual exposure and returned most parameters to those of controls.

• Journal of Chest Surgery
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• v.29 no.8
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• pp.850-860
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• 1996

Oxygen free radicals and their metabolites have been implicated as possible causes of reperrusion injury In animal models. Their role in the clinical setting is still controversial. The aim of this study was to evaluate the degree of tissue damage, oxidative stress. and changes in the antioxidant enzyme system in patients undergoing cor nary artery bypass graft operations(CABG) with myocardial protection by cold blood cardioplegia. In patients undergoing CABG(n:10). the levels of lactate dehydrogenate(LDH), creatine phosphokinase MB fraction(CK-MB), and malondialdehyde(M DA) were measured In the coronary sinus effluent before aortic cross clamping and 20 minutes after reperfusion. At the same time, the myocardial tissue activities of superoxide dismutase(SOD). catalase(CAT), glutathione peroxiddse(GSHPX), glutathione reductase (GSSGRd), and glucose 6-phosphate dehydrogenate(GfPDH ) were determined in the right atrial auricle excised before aortic cross clamping and in the left atrial auricle excised 20 minutes after reperfuslon. The levels of increased significantly after reperrusion(p< U.05). There were no significant changes in CAT and CfPDH levels. Western blot analysis was performed to study the induction of antioxidant enzyme and demonstrated increased amount of Cu,Zn-SOD.

• Preventive Nutrition and Food Science
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• v.14 no.2
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• pp.95-101
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• 2009

In this study, we assessed the effects of Se-methylselenocysteine (MSC) pretreatment on the antioxidant system in the pancreas and the development of alloxan-induced diabetes in rats. The rats were treated with MSC at a dose of 0.75 mg/rat/day for 2 weeks. The MSC-treated rats evidenced significantly increased glutathione content, GSH/GSSG ratio, and glutathione peroxidase (GPx) and glutathione reductase (GRd) activities in the pancreas. Diabetes was induced via alloxan injection. The alloxan-diabetic rats evidenced significantly reduced glutathione content and glucose 6-phosphate dehydrogenase (G6PD) activity and increased catalase activity in the pancreas, when measured 3 days after the alloxan injection. 2-week MSC pretreatment was shown to prevent the alloxan-induced hyperglycemia as well as changes in glutathione content, G6PD activity, and catalase activity. The results of this study indicate that the prevention of alloxan-diabetes by MSC pretreatment is associated with its effects on antioxidants in the pancreas, namely, the increase in cellular content and the reduction of glutathione by the facilitation of glutathione recycling induced via increased GPx, GRd, and G6PD activities.