• Korean Journal of Acupuncture
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• 제19권2호
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• pp.57-61
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• 2002

천궁약침액을 7일간 중완혈, 간수혈 및 임의혈에 투여한 후 마우스의 간에서 유도되는 phase I enzyme 억제 효과를 살펴본 결과 천궁 약침액은 CYP 1A1를 저해하였고, 생체의 CYP 2E1의 활성도 억제하였으므로 천궁 약침액은 암예방 효과가 있을 것으로 사료된다.

• 사상체질의학회지
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• 제17권2호
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• pp.64-73
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• 2005

1. Objectives The purpose of this study was to investigate the effects of the enzyme activity of Palmulgunja-tang with administered orally solution on cytochrome P450 isozyme 2. Methods This study was carried on through following methods. We treated the rat with the {3-naphthoflavone (${\beta}NF$) of 80mg/kg for 3 days i.p injection. Firstable, microsomal protein was separated and total intracellular protein test was done. Then GOT and GPT were measured and assay of cytochrome P450 IAI/2 enzyme activity was performed according to the method of EROD and MROD. (Ethoxyresorufin-O-deethylase(EROD) activity was used to measure cytochrome P450 lAI activity and methoxyresorufin O-demethylase(MROD) activity was used to measure cytochrome P450 lA2 activity. ) 3. Results and Conclusions 1) PGT recovered the liver damage on ${\beta}NF$ inducible CYP IAI/2 by pre-post and high-low condition. 2) At concentration of post-treated 50mg!kg of PGT, the inhibiting of $\betaNF$ metabolites to liver of rat cytochrome P450 lAl was inhibited by 53.0% respectively. 3) PGT showed 36.0% inhibition of ${\beta}NF$-induced lA2 activity at the concentration post-treated 50mg/kg.

• Fisheries and Aquatic Sciences
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• 제5권1호
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• pp.28-31
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• 2002

Effects of cimetidine, a cytochrome P450 inhibitor, on the benzo[a]pyrene (BaP)-mediated cytochrome P450 induction and lipid peroxidation of liver in olive flounder, Paralichthys olivaceus, were investigated. Fish were fed either a cimetidine-supplemented diet or a cimetidine-free control diet once daily to satiation for 3 days. After 6 hrs of last feeding, the fish received intraperitoneal (i.p.) injection of BaP (20 mg/kg of body weight) dissolved in sterile corn oil $(100 \mu L)$ or received only a corn oil i.p. injection. At 1, 2, 3, and 7 days after the injection, hepatic cytochrome P450 and thiobarbituric acid reactive substances (TBARS), an indicator of lipid peroxidation, were analyzed. BaP injection resulted in an increase of hepatic cytochrome P450, and the fish fed the cimetidine-supplemented diet before injection of BaP showed delayed increase of hepatic cytochrome P450 compared to the fish fed a cimetidine-free diet and BaP injected. Injection of BaP clearly induced hepatic lipid peroxidation, and consistently higher TBAR values were shown in the fish fed a cimetidine­supplemented diet before injection of BaP than the fish injected with BaP alone.

• 한국자원식물학회지
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• 제21권2호
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• pp.139-143
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• 2008

다섯 종류의 가지과 식물을 대상으로 elicitor에 의해 생합성 되는 capsidiol의 함량을 측정하고 생합성에 관련된 P450 효소의 활성과 관련 유전자 발현을 조사하였다. 고추, 피망 및 담배는 capsidiol의 생합성에 관련된 두개의 유전자인 cyclase와 P450 유전자가 세포내에 존재하였고, elicitor의 처리에 의하여 유전자의 발현이 유도되고 효소의 촉매가 이루어 졌다. 가지세포에는 두개의 유전자가 게놈상에 존재하지만 P450 유전자는 발현되나, cyclase 유전자의 발현은 나타나지 않았다. 감자에는 capsidiol의 생합성에 관련된 P450 및 cyclase 유전자 모두가 존재하지 않은 것으로 나타났다. 본 실험에 사용된 P450과 cyclase 유전자는 식물이 정상상태에 있을 때는 전혀 발현되지 않으나 elicitor에 의해 특이적으로 유도 되는 특징을 보였고, 식물체 조직이나 기관별로 다양한 발현 양상을 보였다.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1993년도 제2회 신약개발 연구발표회 초록집
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• pp.100-100
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• 1993

Antiestrogen은 에스트로젠 의존성 유방암 치료에 사용되는 약물로써 표적 세포 내에서 에스트로젠 수용체와 작용하여 세포 증식 억제 작용을 나타내고 동시에 에스트로젠 수용체와는 구분되는 소포체 분획의 antiestrogen specific binding site (AEBS) 와도 결합을 하는 것으로 알려져 있다. 그러나, 아직 이 AEBS의 생리적 또는 약리적 기능은 밝혀져 있지 않다. 따라서 본 실험에서는 AEBS의 기능을 조사하기 위하여 cytochrome P45O III 효소군과 AEBS와의 관계를 자옹 백서를 이용하여 면역 화학 반응 실험 및 경쟁적 결합 반응 실험을 하였고, 그 결과는 다음과 같다. 1) AEBS에 대해서 SKF-525A와 metyrapone은 결합 능력을 나타내었다. 2) 자성쥐에서는 주령이 증가함에 따라 cytochrome P450양이 감소하였다. 3) 자옹성쥐 모두에서 phenobarbital 처치에 의해 cytochrome P450 III 효소양이 증가하였고, AEBS도 증가하였다. 4) 웅성쥐에서는 testosterone에 의하여 AEBS가 증가하였다. 5) 자웅성쥐 모두에 tamoxifen 관류시 cytochrome P450 III 효소양이 증가하였고 estradiol과 병용 관류시에는 tamonifen 단독 관류시보다 감소하였다. 이상의 결과에서 tamoxifen이 cytochrome P450 III을 유도할 수 있는 것으로 사료되며 cytochrome P450 III 효소군과 안티에스트로젠 결합부위와 밀접한 관련이 있는 것으로 생각된다.

• Toxicological Research
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• 제11권2호
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• pp.205-213
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• 1995

This study was undertaken to investigate the effects of organic solvents on xenobiotic metabollzing enzyme system in vivo by meaas of experimental conditions i.e. (1) single group which was treated by benzene (B), toluene (T) and xylene (X), respectively, (2) combination group which was treated by mixture of benzene+toluene (BT), benzene+xylene (BX), and toluene+xylene (TX), respectively, (3) mixture group which was treated by benzene+ toluene+xylene mixture (M), and to interpreat the interaction between the organic solvents metabolizing enzymes. 1. The contents of cytochrome P-450 in liver microsomes were increased (p < 0.01) in organic solvents treated groups, and the contents of cytochrome P-450 were increased by following order of B < T < M < BT=BX < X < TX. 2. The activity of cytochrome P-450 dependent AHHase was significantly higher in organic solvents treated groups than in control group (p < 0.01), and the activity of AHHase was increased by following order of B < T < BT=BX=TX=xylene < M. 3. The activity of NADPH P-450 reductase was significantly higher in organic solvents treated groups than in control group (p < 0.01), and the order of M < combinated group < X < T

• Toxicological Research
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• 제32권2호
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• pp.89-93
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• 2016

Human cytochrome P450 enzymes (P450s, CYPs) are major oxidative catalysts that metabolize various xenobiotic and endogenous compounds. Many carcinogens induce cancer only after metabolic activation and P450 enzymes play an important role in this phenomenon. P450 1B1 mediates bioactivation of many procarcinogenic chemicals and carcinogenic estrogen. It catalyzes the oxidation reaction of polycyclic aromatic carbons, heterocyclic and aromatic amines, and the 4-hydroxylation reaction of $17{\beta}$-estradiol. Enhanced expression of P450 1B1 promotes cancer cell proliferation and metastasis. There are at least 25 polymorphic variants of P450 1B1 and some of these have been reported to be associated with eye diseases. In addition, P450 1B1 polymorphisms can greatly affect the metabolic activation of many procarcinogenic compounds. It is necessary to understand the relationship between metabolic activation of such substances and P450 1B1 polymorphisms in order to develop rational strategies for the prevention of its toxic effect on human health.

• 대한의생명과학회지
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• 제7권2호
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• pp.65-70
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• 2001

We have carried out PCR reactions to investigate if cytochrome P450 (P450) enzymes (1A1, 1A2, 2C8, 2E1 and 3A4), which are well hewn to be the key enzymes in detoxification process and/or synthesis of steroids in the liver, are expressed in the human brain, too. P450 1A1, 2C8 and 2E1 were expressed clearly. However, P450 1A2 and 3A4 were not detectable. Their expression levels in the human brain could be extremely low or they were not expressed at all. One base substitution at nucleotide 290 (A->G) was identified in P450 1A1. It is suspected to be an individual polymorphism. Our results should contribute to the better understanding of the role of cytochrome P450 enzymes in the human brain.

• Archives of Pharmacal Research
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• 제21권3호
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• pp.305-309
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• 1998

Human cytochrome P450 1A2 is one of the major cytochrome P450s in human liver. It is known to be capable of activating a number of carcinogens such as arylamines and heterocyclic amines. In order to develop the new bacterial mutagenicity test system with human P450, a full length of human P450 1A2 cDNA inserted into pCW bacterial expression vector was introduced to Escherichia coli WP2 uvrA strain which is a well-known E. coli strain for bacterial reverse mutagenicity assay. Expressed human P450 1A2 showed typical P450 hemoprotein spectra. Maximum expression was achieved at 48 hrs after incubating at $30^{\circ}C$ in terrific broth containing ampicillin, IPTG and other supplements. High level expression of P450 1A2 in E. coli WP2 uvrA membranes was determined in SDS-PAGE. The well-known mutagens 2-aminoanthracene and MElQ increased the revertant colonies of E. coli WP2 uvrA expressing human P450 1A2 without an exogenous rat hepatic post-mitochondrial supernatant (S9 fraction) in a dose-dependent manner. The results show that the functional expression of human P450 in bacterial mutagenicity tester strain will provide a useful tool for studying the mechanism of the mutagenesis and carcinogenesis of new drugs and environmental chemicals.

• Journal of Nutrition and Health
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• 제35권6호
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• pp.643-649
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• 2002

This study was done to investigate effects of ${\gamma}$-irradiated pork feeding on the formation of glutathione S-transferase placental form positive (GST-P$^{+}$) foci, lipid peroxidation, cytochrome P450 system and microsomal glucose 6-phosphatase activity in diethylnitrosamine (DEN)-initiated rat hepatocarcinogenesis. Weaning Sprague-Dawley male rats were fed the diet containing ${\gamma}$-irradiated ground pork at the dose of 0, 3, 10, 30 kGy as a 20％ of protein source for 8 weeks. One week after feeding, rats were intraperitoneally injected twice with a dose of DEN (50 mg/kg BW). As a promote.,0.05％phenobarbital was fed in drinking water from one week after DEN treatment until the end of experiment. At the end of 8th week, rats were sacrificed and hepatic GST-P$^{+}$ foci, microsomal malondialdehyde (MDA) and conjugated diene contents were determined. In addition, cytochrome P450 content and the activities of NADPH cytochrome P450 reductase and glucose 6-phosphatase were also measured. There was no significant effect by gamma irradiation on microsomal MDA content, conjugated diene, cytochrome P450 content and activities of NADPH cytochrome P450 reductase and glucose 6-phosphatase. However with DEN treatment, microsomal MDA content showed a increasing tendency. Cytochrome P450 content was also significantly increased while microsomal glucose 6-phophatase activity was significantly decreased with DEN treatment. However the activity of NADPH cytochrome P450 reductase was not affected. An interesting finding in this study was that the number and area of hepatic GST-P$^{+}$ foci of rats fed gamma irradiated pork were tended to be decreased by high dose of irradiation, but were not significantly different. These results might imply that the consumption of low dose of gamma irradiated pork does not affect the formation of hepatic GST-P$^{+}$ foci and lipid peroxide and membrane stability.ability.