• Journal of Microbiology and Biotechnology
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• 제15권1호
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• pp.183-187
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• 2005

Abstract The cancer chemopreventive potential of chitosanoligosaccharides was investigated by measuring the induction of quinone reductase and glutathione S-transferase activities and inhibition of cytochrome P450 1A1, 2B1, and 2E1 activities. Chitosanoligosaccharide I (1-${\kappa}$Da${\kappa}$Da) significantly induced glutathione S-transferase activity with a maximal 1.5-fold increase at 500 ${\mu}$g/ml, while chitosanoligosaccharide II (3-${\kappa}$Da${\kappa}$Da) (500 ${\mu}$g/ml) strongly induced quinone reductase (p<0.01) and glutathione S-transferase (p<0.005) activities. The in vitro incubation of rat liver microsomes with chitosanoligosaccharides I and II (2.5, 5, 50, and 500 ${\mu}$g/ml) showed a dose-dependent inhibiton of cytochrome P450 1A1, 2B1, and 2E1 activities. Chitosanoligosaccharide II was a more potent inhibitor of cytochrome P450 2B1 activity than chitosanoligosaccharide I. Accordingly, these findings suggest that chitosanoligosaccharides are potential chemopreventive agents.

• 한국수산과학회지
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• 제34권3호
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• pp.194-198
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• 2001

PCBs의 경구 투여에 의한 틸라피아, Oreochromis niloticus의 간 cytochrome P450 효소계의 변화를 30일간 관찰하였다. 30일 동안 PCBs 0.05, 0.25 및 0.50mg/kg을 투여했을 때, HSI는 각각 1.81, 1.72 및 $1.54\%$ 감소하였으나, 유의한 차이는 인정되지 않았다. PCBs 0.05mg/kg에 노출된 간 cytochrome P450 농도는 30일째 대조구에 비해 1.4배 유의한 증가를 나타냈고, 0.25mg/kg 이상에서는 실험 20일 이후부터 유의적으로 증가하였다. EROD 활성도는 PCBs 0.05 mg/kg에서 실험 30일째부터 유의하게 증가하여 약 8배 높게 나타났다. 또한, PCBs 0.25mg/kg이상에서는 실험 20일째부터 유의하게 증가하여 30일째부터는 각각 18 및 22배의 증가를 나타냈다. PROD는 PCBs $0.05\~0.50mg/kg$에 노출시킨 개체에서 $0.78\~1.93$pmole/mg protein이 측정되어 대조구에 비해 뚜렷한 변화는 관찰되지 않았다. 이상의 결과는 자연 수역에서 PCBs의 잔류에 따라 먹이를 통해 틸라피아의 체내에 적어도 0.05 mg/kg 이상이 30일간 이상 계속적으로 유입될 경우에 간 cytochrome P450농도 및 EROD 활성도는 증가될 것으로 추정된다.

• 한국생물물리학회:학술대회논문집
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• 한국생물물리학회 1998년도 학술발표회
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• pp.16-16
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• 1998

The role of phospholipids in the membrane binding and subsequent insertion of the microsomal protein rabbit cytochrome P450 (P450) lA2 into phospholipid bilayers was investigated. The insertion of P450 lA2 into phospholipid bilayers was determined by the amount of quenching of Trp fluorescence of P450 lA2 by pyrene and brominated and doxyl-labeled phospholipids.(omitted)

• Fisheries and Aquatic Sciences
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• 제16권4호
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• pp.261-265
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• 2013

The study was conducted to investigate the responses of the hepatic microsomal cytochrome P450 monooxygenase system in the rock bream Oplegnathus fasciatus after chronic exposure to 0, 1, 2, 4, and $8{\mu}g/L$ tributyltin (TBT) concentrations for 4 weeks. Hepatic cytochrome 450 content and ethoxyresorufin O-deethylation (EROD) activity were found to significantly increase in fish treated with the higher concentration of TBT (${\geq}4{\mu}g/L$); however, no significant changes were observed in penthoxyresorufin O-deethylation (PROD) activity in all treated groups compared to the control group. These findings suggest that exposure to a low TBT concentration (${\geq}4{\mu}g/L$) has the potential to induce cytochrome 450 content and EROD enzyme activity in hepatic tissue in the rock bream.

• 한국독성학회:학술대회논문집
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• 한국독성학회 2001년도 International Symposium on Dietary and Medicinal Antimutgens and Anticarcinogens
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• pp.189-189
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• 2001

For a continuous expression of human cytochrome p450 3A5 (CYP3A5) and NADPH-cytochrome P450 reductase (CYPR) proteins, bicistronic construct (CYP3A5BC-LNCX2) was made using internal ribosome entry site (IRES). As for mammalian cell expression, we used pLNCX2 retroviral vector; and using calcium phosphate, plasmid transfer was achieved in 293GPG cell and transduced in Chinese hamster ovary (CHO) cell.(omitted)

• Archives of Pharmacal Research
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• 제18권3호
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• pp.179-182
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• 1995

Previous study showed that $CCl_4$ administration evoked a rapid decrease in cytochrome $P_{450}$ 2E1 protein soon after the exposure due to posttranslational inhibition(Biochem. Biophys. Res. Commun. 179:449-454, 1991). In this report, aniline hydroxylase and the amounts of immunoreactive $P_{450}$ 2E1 were rapidly decreased during day 1 to 2 and recovered during day 3 to 4 after a single dose of $CCl_4$. The activity of pentoxyresorufin-O-dealkylase was also suppressed at day 1 and began to repair from day 2. However, the decrease in immunoreactive $P_{450}$ 2C content was not observed. The decreases in $P_{450}$ 2E1 enzyme activity and immunoreactive protein by acute $CCl_4$ treatment were accompanied by a decline in $P_{450}$ 2E1 mRNA level. The data thus suggested a pretranslational reduction of $P_{450}$ 2E1 during day 1 to 2 after acute $CCl_4$ treatment.

• Journal of Oral Medicine and Pain
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• 제20권2호
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• pp.461-475
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• 1995

The purpose of this study was to investigate the effect of alcohol and stress on liver and buccal mucosa in guinea pig by immunological methods. Especially, Cytochrome P450 (CYP) which in oxidase during alcohol metabolism and bioactivator to carcinogen was used as an indicator in this study. 48 guinea pigs were used in this study. The experimental guinea pig were divided into three groups: The first was a group with giving alcohol-15%(v/v) ethyl alcohol, the second group was a with giving stress in the $0^{\circ}C$ water and the third was a control group. Every 4 guinea pigs of each group were sacrificed weekly-first, second, third, fourth week after experiment and extracted liver tissues and buccal mucosa. The liver tissues were observed by using immunoblotting technique (Western blot) and buccal mucosa were observed by immunofluorescence technique. The results were as follows: 1. By the alcohol and stress, Cytochrome P450 was amplified positive in the liver tissues at third week. 2. By the alcohol and stress, Cytochrome P450 was not detected in the buccal mucosa at any period.

• Korean Journal of Acupuncture
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• 제21권2호
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• pp.139-145
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• 2004

Objectives : Inhibition of phase I enzymes such as cytochrome P450 (CYP) 1A1 or 1A2 is considered a major mechanism of protection against initiation of carcinogenesis. The inhibition of toxic enzymes and CYP were studied with so many oriental herbral medicine. Recently, numerous polysaccharides and polysaccharide-protein complexes have been isolated from mushrooms and used as a source of therapeutic agents. The most promising biopharmacological activities of these polymers are their immunomodulation and anti cancer. But, in this study the inhibitory effect was on the aqua-acupuncture of Lentinus edodes. Materials : Lentinus edodes aqua-acupuncture solution (LEAS) was prepared and tested for the inhibition of cytochrome P450 (CYP) 1A1 and 1A2 activities. LEAS type I from fruit body of these mushrooms. Type II was extracted from cultured broth of Lentinus edodes mycelum. Results : LEAS type I and type II were significantly inhibited CYP 1A1 and 1A2 enzymes at concentration of 5.0 and 10.0 mg/ml. Conclusion : These results suggested that LEAS may act as block agent against carcinogenesis by inhibition of phase I enzymes.

• 환경위생공학
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• 제12권3호
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• pp.87-94
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• 1997

Influences of clotrimazole on the blood cholesterol and HDL-cholesterol level were studied in rats. Rats were provided food and water ad libitum and clotrimazole and methylcellulose were gavaged for 6 days. Clotrimazole was suspended in 1% methylcellulose solution as and administered at concentration 20mg/Kg, 40mg/Kg, 60mg/Kg. Body weight gain and liver weight/body weight ratio, serum cholesterol level, serum HDL-cholesterol level, serum triglyceride level, the activity of cytochrome p450 and erythromycin demethylase were determined at 6th day. Clotrimazole decreased the body weight gain a little as compared with control group and did not show any influence on liver weight/body weight ratio. Clotrimazole increased the serum HDL-cholesterol and serum triglyceride level significantly. Clotrimazole increased the microsomal cytochrome P450 significantly and increased the erythromycin demethylase (cytochrome P450 IIIA) significantly too. It might be conclued that clotrimazole showed a little influence on body weight and increased the serum lipid, especially HDL-cholesterol level. It also increased microsomal cytochrome P450 IIIA significantly. It might be concluded that clotrimazole showed a corelative influence between HDL-cholesterol and cytochrome P450 IIIA. In these results clotrimazole can be used as an anti-atherosclerotic agent by increasing the HDL-cholesterol but it is necessary that cloreimazole will show any adverse or side action on body or not.

• 동의생리병리학회지
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• 제21권6호
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• pp.1534-1542
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• 2007

In this study, the liver protective effect of the hot water extracts of Scutellaria radix (SR) was investigated. The SR exhibited a hepatoprotective activity against $CCl_4$-induced liver damage in Sprague-Dawley (SD) rats and Chang cell. And the SR also showed significant decrease of malodialdehyde (MDA) and increase of glutathion (GSH), catalase activity in rat liver homogenate. The expression of cytochrome P450 2E1 (CYP2E1), measured by RT-PCR and western blot, was significantly decreased in the SR treated SD rats and Chang cell. But $CCl_4$ and SR has no significant effect on 1A1 and 3A1 isoform of cytochrome P450. Based on these findings, it is suggested that hepatoprotective effects of SR possibly related to antioxidative effects and downregulation of CYP2E1 expression.