• 약학회지
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• 제44권5호
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• pp.379-383
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• 2000

Stanozolol (STZ, 17$\alpha$-methyl-17$\beta$-hydroxy-5$\alpha$-androstano-(3,2-c) pyrazole), an anabolic steroid, is an abused drug by body-builders or atheletes, as well as medicine for treatment of aplastic anemia and vascular thrombosis. In human volunteers, the major urinary metabolite of STZ was reported to be 3'-hydroxystanozolol that was identified by gas chromatography-mass selective detector (GC/MSD). The objective of this experiment is to investigate the in vitro metabolism of STZ in liver S-9 faction of polychlorinated biphenyl-induced rats. Reaction mixture including STZ as substrate and the S-9 faction was extracted with diethyl ether and quantified by the selected ion monitoring mode of GC/MSD. The selected concentration of substrate STZ is 100 nmole and the selected time for incubation in the reaction mixture was determined to 60 min. The amount of 3'-hydroxystanozolol produced was increased by about 6-fold in the reaction medium including the liver S-9 fraction of polychlorinated biphenyl-induced rats, compared to that of untreated rats. Inhibitors of cytochrome P450, SKF-525A and 7,8-benzoflavone, decreased the production of 3'-hydroxystanozolol by about 89~100% and 65~75%, respectively; In conclusion, hydroxylation of STZ into 3'-hydroxystanozolol is confirmed by GC/MSD and is catalyzed by cytochrome P450.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1996년도 제4회 추계심포지움
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• pp.165-169
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• 1996

The cytochrome P450 (P450) proteins have been studied extensively because of their prominent roles as catalysts in the oxidations of drugs, carcinogens, steroids, alkaloids, vitamins, and other important chemicals (Guengerich, 1991). In the past decade the study of these enzymes has been advanced by the cloning of cDNAs and expression of the proteins in several heterologous vector systems. One approach that has been employed in this and other laboratories is expression in bacteria. To date at least 31 different mammalian P450s have been expressed in Escherichia coli-band systems (Guengerich et al., 1996). In most of these cases the N-terminus has been altered to facilitate better expression (Barnes et al., 1991).

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
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• pp.186.1-186.1
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• 2003

Certain polycyclic aromatic hydrocarbons (PAHs) have been reported to induce cytochrome P450 (P450) 1A1 and 1A2. In the present studies, the effects of six well-known PAHs on the activities of hepatic and pulmonary P450 enzymes were investigated in male ICR mice. When mice were treated intraperitoneally with 3, 10 and 30 mg/kg of individual PAHs for 3 consecutive days, the activities of ethoxyresorufin- and methoxyresorufin-O-dealkylases were significantly and (omitted)

• 대한수의학회지
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• 제38권1호
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• pp.17-28
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• 1998

Drug-metabolizing activities of Korean native cattle and swine were investigated from viewpoints of the cytochrome P-450's level, their dependent mixed function oxidase activities, the reactive oxygen species formation and cytosolic enzyme acitivities from each liver homogenates. Level of cytochrome P-450 in the liver microsome of Korean native cattle was $0.28{\pm}0.05nmole/mg$ and that in pigs $0.35{\pm}0.03nmole/mg$. Level of cytochrome $b_5$ of Korean native cattle was $0.24{\pm}0.06nmole/mg$, and that of pigs $0.2{\pm}0.05nmole/mg$, showing no difference between two species. NADPH P-450 reductase were higher in Korean native cattle ($58.3{\pm}5.3nmole/mg/min$) than in pigs ($29.9{\pm}3.8nmole/mg/min$)(p<0.01). The activities of cytochrome P-450 dependent monooxygenases such as ethoxyresorufin O-deethylase (cattle, $96.5{\pm}12.5nmole/mg/min$ ; pigs, $13.6{\pm}2.1nmole/mg/min$), N-benzphetamine N-demethylase (cattle, $5.23{\pm}0.82nmole/mg/min$ ; pigs, $0.76{\pm}0.3nmole/mg/min$) and aniline hydroxylase (cattle, $0.95{\pm}0.1nmole/mg/min$ ; pigs, $0.33{\pm}0.08nmole/mg/min$) were much higher in Korean native cattle than in swine(p<0.01). However, the activity of testosterone $7{\alpha}$-hydroxylase was higher in swine ($90.4{\pm}1.2nmole/mg/min$) than cattle (cattle, $32.8{\pm}1.2nmole/mg/min$). Interestingly, testosterone $16{\alpha}$-hydroxylase, a marker enzyme for P-450 IIA was not detected in both animal species. These results suggest that Korean native cattle and pigs have high contents of P-450 IA1 and P-450 IIIA. Total sulfhydryl compound (cattle, $10.3{\pm}1.1nmole/mg$ ; Pigs, $14.5{\pm}1.8nmole/mg$) and glutathione related enzymes except glutathione reductase (cattle, $38.1{\pm}7.9nmole/mg/min$; swine, $22{\pm}3.6nmole/mg/min$) showed higher levels in swine than in Korean native cattle. Superoxide dismutase (cattle, $7.64{\pm}0.84nmole/mg/min$ ; pigs, $4.47{\pm}0.94nmole/mg/min$) and catalase (cattle, $30.4{\pm}3.7nmole/mg/min$ ; pigs, $17.2{\pm}1.8nmole/mg/min$) were remarkably higher in Korean native cattle than in swine (p<0.05).

• 한국약용작물학회지
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• 제10권1호
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• pp.29-36
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• 2002

예로부터 우리나라와 중국을 비롯한 동양에서는 음양곽을 강정제 및 정력강화제로 사용되어왔다. 본 연구는 흰쥐에게 장기간 음양곽 물 추출물을 공급하고(0.025%,w/v) 노화에 따른 생리적인 변화와 간의 이물질 대사 효소군의 활성도에 미치는 영향을 조사하였다. 흰쥐에 음양곽의 물 추출물 공급으로 특이한 질병은 발견되지 않았으나 24개월에서 간과 신장의 무게는 대조군에 비해 다소 증가하였으며 혈청의 glutamate-oxaloacetate transminase와 glutamate-pyruvate transminase 활성도도 증가하였다 간의 이물질 대사효소 중 cytochrome P450 NADPH-cytochrome P450 reductase, benzphetamine N-demethylase ethoxycoumarine O-deethylase, glutathione S-transferase의 활성도는 두 그룹 모두 노화에 따라 감소하였으며, 음양곽 물 추출물 투여에 의해 감소현상이 악화되었다. 간의 cytochrome B5의 함량과 NADH cytochrome b5 reductase의 활성도도 노화에 따라 감소되었으나 같은 나이에서 두 그룹간의 뚜렷한 차이를 보이지 않았다. 이상의 결과로 보아 흰쥐에 장기간 음양곽 물 추출물을 공급은 노년기에 노화에 따라 감소하는 간의 이물질 대사 기능에 부담을 수도 있다는 것을 암시해 준다.

• 생약학회지
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• 제34권2호통권133호
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• pp.161-165
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• 2003

Ethanol extract from Thesium chinense Tunczaninov (TCTE) was tested for breast cancer chemopreventive activity by measuring 7,12-dimethylbenz[a]anthracene (DMBA) - induced cytochrome P450 1A1 activity, induction of quinone reductase and glutathione S-transferase, and glutathione level. TCTE significantly inhibited cytochrome P45O 1A1 activity at the concentration of 90 and 150 mg/ml. TCTE induced quinone reductase activity in a dose-dependent manner in a concentration range of 3-150 mg/ml. In addition glutathione S-transferase activity and glutathione level were increased with TCTE in cultured murine hepatoma Hepa1c1c7 cells. These results suggest that TCTE has breast cancer chemopreventive potential by inhibiting cytochrome P45O 1A1 activity, inducing quinone reductase and glutathione S-transferase activities, and increasing GSH level.

• Journal of Microbiology and Biotechnology
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• 제16권2호
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• pp.295-298
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• 2006

Actinomycetes are ubiquitous Gram-positive soil bacteria and a group of the most important industrial microorganisms for the biosynthesis of many valuable secondary metabolites as well as the source of various bioconversion enzymes. Cytochrome P450 hydroxylase (CYP), a hemebinding protein, is known to be involved in the modification of various natural compounds, including polyketides, fatty acids, steroids, and some aromatic compounds. Previously, six different novel CYP genes were isolated from a rare actinomycetes called Sebekia benihana, and they were completely sequenced, revealing significant amino acid similarities to previously known CYP genes involved in Streptomyces secondary metabolism. In the present study, these six CYP genes were functionally expressed in Streptomyces lividans, using an $ermE^{*}$ promoter-containing Streptomyces expression vector. Among six CYP genes, two S. benihana CYP genes (CYP503 and CYP504) showed strong hydroxylation activities toward 7-ethoxycoumarin. Furthermore, the recombinant S. lividans containing both the S. benihana CYP506-ferredoxin genes as well as the S. coelicolor feredoxin reductase gene also demonstrated cyclosporin A hydroxylation activity, suggesting potential application of actinomycetes CYPs for the biocatalysts of natural product bioconversion.

• Archives of Pharmacal Research
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• 제16권2호
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• pp.89-93
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• 1993

Incubation of $S(-)-^3H$-nicotine with rabbit lung microsomes in the presence of dioxygen and NADPH results in the formation of metabolities that bind covalently to microsomal macro-molecules. The addition of cytochrome P-450 monooxygenase inhibitors, $\alpha$-methylbenzyl ami-nobenzotriazole and aroclor 1260, inhibited both (S)-nicotine metabolism and covalent binding. The relative rates of oxidation of nicotine $\Delta^{1',5'}$ iminium ion to continine indicates that lung $100,000\times{g}$ supematant catalyzed this oxidation approximately 18 times slower than that of liver system based on mg of protein, and increased covalent interactions. Since than that of liver system based on mg of protein, nd increased covalent interactions. Since the activity of lung iminium oxidase appears much lowr than the liver, it is tempting to speculate that localized concentrations of nicotine $\Delta^{1',5'}$ iminium ion in the lung will survive for a longer period of time. These results support that cytochrome P-450 catalyzed oxidation of nicotine leads to the formation of reactive nad electrophilic intemediates capable of chemical interactions with biomacromolecules.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-1
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• pp.88-88
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• 2003

The syntheses of different types of stilbenoid libraries have been studied recently. In these courses, the screening of the generated natural product-mimic focused libraries led to the identification of the novel lead compounds for human cytochrome P450 (CYP) lAs, melanin production, and sortase A. A library of trans-stilbene derivatives was prepared through a new efficient solution pahse synthetic pathway and their inhibitory activities were evaluated on human cytochrome P450s(CYP) 1A1, 1A2, and 1B1 to find a potent and selective CYP1 inhibitor. (omitted)

• Journal of Microbiology and Biotechnology
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• 제16권6호
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• pp.974-978
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• 2006

The cytochrome P450 monooxygenase from the pikromycin biosynthetic gene cluster in Streptomyces venezuelae, known as PikC, was observed to hydroxylate the unnatural substrate indole to indigo. Furthermore, the site-directed mutagenesis of PikC monooxygenase led to the mutant enzyme F171Q, in which Phe171 was altered to Gln, with enhanced activity for the hydroxylation of indole. From enzyme kinetic studies, F171Q showed an approximately five-fold higher catalytic efficiency compared with the wild-type PikC. Therefore, these results demonstrate the promising application of P450s originating from Streptomyces, normally involved in polyketide biosynthesis, to generate a diverse array of other industrially useful compounds.