• 대한한방내과학회지
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• 제29권4호
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• pp.846-855
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• 2008

Objects : The aim of this study was to investigate the influence of five herbal medicines on cytochrome P450 3A4 drug-metabolizing enzymes in human liver microsomes. Methods : To use human liver microsomes, an extract of five herbal medicines, which are Artemisia princeps Pampan, Sophora jeponica Linne, Panax notoginseng F. H. Chen, Lithospermum Erythrorhizon Sieb., and Cirsium maackii Maxim, which together are called Jihyulyak(止血藥, drugs for arresting bleeding, hemostatics), was co-incubated and measured for relative enzyme activity in incubation condition compared to ketoconazole, a representative inhibitor of CYP 3A4. Results : We showed that all five of the traditional herbal medicines had no inhibition effect of CYP 3A4 at 10, 20, 30, 40, and $50{\mu}g/ml$ doses in human liver microsomes, although Sophora japonica Linne(SJL) showed a little inhibition at about 81% inhibition rate of control. However, this result is not enough to prove that SJL has a CYP 3A4 inhibition effect. Moreover, we can't make sure that those rates had significant induction effect on CYP 3A4. Conclusions : The result of this study could support that those herbal medicines are safer than chemical drugs, even if this is the basic step to prove that result.

• Toxicological Research
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• 제26권1호
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• pp.47-52
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• 2010

The Malassezia fungi are responsible for various human skin disorders including dandruff and seborrheic dermatitis. Of the Malassezia fungi, Malassezia globosa (M. globosa) is one of the most common in human scalp. The completed genome sequence of M. globosa contains four putative cytochrome P450 genes. To determine the roles of Malassezia P450 enzymes in the biosynthesis of ergosterol, we isolated MGL3996 gene from M. globosa chromosomal DNA by PCR. The MGL3996 gene encodes an enzyme of 616 amino acids, which shows strong similarity with known CYP52s of other species. MGL3996 gene was cloned and expressed in Pichia pastoris (P. pastoris) heterologous yeast expression system. Using the yeast microsomes expressing MGL3996 protein, a typical P450 CO-difference spectrum was shown with absorption maximum at 448 nm. SDS-PAGE analysis revealed a protein band of apparent molecular weight 69 kDa and Western blot with anti-histidine tag antibody showed that MGL3996 was successfully expressed in P. pastoris. Cloning and expression of a new P450 gene is an important step to study the P450 monooxygenase system of M. globosa and to understand the role of P450 enzymes in pathophysiology of dandruff.

• 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)

• BMB Reports
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• 제31권4호
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• pp.391-398
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• 1998

In vitro effects of acetone, methanol, and dimethylsulfoxide (DMSO) on liver microsomal cytochrome P450 (P450) content, and P450-dependent arylhydrocarbon hydroxylase (AHH) and 7-ethoxycoumarin O-deethylase (ECOD) activities were studied in rats. Acetone at 1% (v/v) enhanced the content ofP450, assayed spectrally in 3-methylcholanethrene (MC)- and ${\beta}-naphthoflavone$ (BNF)-inducible microsomes by 18 and 7%, respectively. Methanol, up to 5% (v/v) applied, also showed enhancement effects on P450 content in liver microsomes from rats treated with phenobarbital (PB), MC, and BNF, as well as uninduced microsomes with similar but low strength. DMSO, however, did not show such enhancing effects at the ranges of the concentrations applied. AHH and ECOD activities in MC-inducible microsomes were also enhanced by acetone at 1%, which was in proportion to the increase in P450 content by the same concentration. However, the P450 content, and AHH and ECOD activities, were decreased by increasing the concentration of acetone. Methanol at the same concentration with acetone also enhanced ECOD activity but not AHH activity in MCinducible microsomes. The enhancing effect of acetone on the enzymes was negligible when the microsomes were pretreated with a specific monoclonal antibody of MC-inducible isozyme. The difference in the effects of these solvents on P450 system might be due to their different properties that cause the P450 active site to be exposed in milieu.

• 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.

• Journal of the Korean Wood Science and Technology
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• 제39권6호
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• pp.469-480
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• 2011

본 연구에서는 Ceriporia sp. ZLY-2010을 이용하여 폴리염화비페닐류의 생분해와 효소 시스템간의 상관관계에 대해 알아보고자 하였다. 폴리염화비페닐 동족체 첨가에 따라 단백질 정량 및 manganese peroxidase (MnP)와 laccase의 활성을 비교하였으며, cytochrome P450 monooxygenase의 저해 정도를 평가함으로써 균체 내 효소가 폴리염화비페닐의 생분해에 끼치는 영향을 구명하였다. 단백질 정량 및 균체 외 효소 활성을 측정해 본 결과, 대조구에 비해 폴리염화비페닐 동족체를 첨가한 실험구에서 단백질 농도 및 효소활성이 더 높게 측정되었다. 단백질 농도의 경우, 2,2',4,4',5,5'-hexachlorobiphenyl을 첨가했을 때, 가장 높은 단백질 농도가 측정되었다. 하지만 MnP와 laccase 활성에서는 상대적으로 염소원자가 적게 치환된 2,3',4',5-tetrachlorobiphenyl을 첨가한 실험구에서 높게 나타나는 경향을 보였다. Cytochrome P450 monooxygenase의 저해 정도를 평가한 결과, 2,3',4',5-tetrachlorobiphenyl을 첨가한 실험구의 경우, 배양 1일째, 저해제 1-aminobenzotriazole 0.1 mM에서 2.73%의 분해율을 나타냈으며, 저해제 첨가 시 생분해율이 크게 감소하는 것으로 나타났다. 2,2',4,4',5,5'-hexachlorobiphenyl 역시, 저해제의 존재 하에 20% 내외의 분해율을 보였으며, 이는 대조구에 비해 약 40% 감소한 비율이다.

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.312.3-313
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• 2002

Recently we have reported that various hydroxystilbenes show strong inhibition of human P450 1 activity. A series of synthetic trans-stilbene derivatives were prepared and their inhibitory potentials were evaluated with the bacterial membrane of recombinant human P450 1A1, 1A2 or 1B1 coexpressed with human NADPH-P450 reductase to find new candidates for cancer chemoprevention, Of the compounds tested. SY-021 (3.5-dimethoxyphenyl vinyl thiophene) exhibited a potent inhibition of human P450 181 with an IC$_{50}$ value of 2 nM. SY-021 also showed the inhibitrion of P450 1A1 with IC$_{50}$ value of 61 nM and P450 1A2 with IC$_{50}$ value of 11 nM. SY-021 showed 31-fold selectivity for P450 1B1 over P450 1A1 and 6-fold selectivity for P450 1B1 over 1A2. We have further investigated the inhibition kinetics of P450 1A1. 1A2 and 1B1 by SY-021. The modes of inhibition by SY-021were non-compeitive for all three P450 1 enzymes. Effect of preincubation with NADPH on inhibition of P450 1B1 by SY-021 was determined. These results suggest that SY-021 is one of the mostj potent inhibitor of human P450 1 enzymes and may be considered as a good candidate for a cancer chemopreventive agent in human

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 2006년도 Proceedings of The Convention
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• pp.51-66
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• 2006

The field of cytochrome P450 pharmacogenomics has progressed rapidly during the past 25 years. Recently, conjugating enzymes including sulfotransferase, acetyltransferase, glucuronosyltransferase and glutathione transferase have been also extensively studied. All the major human drug-metabolizing P450 enzymes and some conjugating enzymes have been identified and cloned, and the major gene variants that cause inter-individual variability in drug response and are related to adverse drug reactions have been identified. This information now provides the basis for the use of predictive pharmacogenomics to yield drug therapies that are more efficient and safer. Today, we understand which drugs warrant dosing based on pharmacogenomics to improve drug treatment. It is anticipated that genotyping could be used to personalize drug treatment for vast numbers of subjects, decreasing the cost of drug treatment and increasing the efficacy of drugs and health in general. It is assumed that such personalized P450 gene-based treatment which is so-called tailor(order)-made drug therapy would be relevant for 10-20% of all drug therapy in the future.

• 한국약용작물학회:학술대회논문집
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• 한국약용작물학회 2006년도 Proceedings of The Convention of The Korean Society of Applied Pharmacology
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• pp.51-66
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• 2006

The field of cytochrome P450 pharmacogenomics has progressed rapidly during the past 25 years. Recently, conjugating enzymes including sulfotransferase, acetyltransferase, glucuronosyltransferase and glutathione transferase have been also extensively studied. All the major human drug-metabolizing P450 enzymes and some conjugating enzymes have been identified and cloned, and the major gene variants that cause inter-individual variability in drug response and are related to adverse drug reactions have been identified. This information now provides the basis for the use of predictive pharmacogenomics to yield drug therapies that are more efficient and safer. Today, we understand which drugs warrant dosing based on pharmacogenomics to improve drug treatment. It is anticipated that genotyping could be used to personalize drug treatment for vast numbers of subjects, decreasing the cost of drug treatment and increasing the efficacy of drugs and health in general. It is assumed that such personalized P450 gene-based treatment which is so-called tailor(order)-made drug therapy would be relevant for 10-20% of all drug therapy in the future.