• Journal of Microbiology and Biotechnology
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• 제22권12호
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• pp.1659-1664
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• 2012

TSAHC [4'-(p-toluenesulfonylamido)-4-hydroxychalcone] is a promising antitumorigenic chalcone compound, especially against TM4SF5 (four-transmembrane L6 family member 5)-mediated hepatocarcinoma. We evaluated the potential of TSAHC to inhibit the catalytic activities of nine cytochrome P450 isoforms and of P-glycoprotein (P-gp). The abilities of TSAHC to inhibit phenacetin O-deethylation (CYP1A2), coumarin 6-hydroxylation (CYP2A6), bupropion hydroxylation (CYP2B6), amodiaquine N-deethylation (CYP2C8), diclofenac 4-hydroxylation (CYP2C9), omeprazole 5-hydroxylation (CYP2C19), dextromethorphan O-demethylation (CYP2D6), chlorzoxazone 6-hydroxylation (CYP2E1), and midazolam 1'-hydroxylation (CYP3A) were tested using human liver microsomes. The P-gp inhibitory effect of TSAHC was assessed by [$^3H$]digoxin accumulation in the LLCPK1-MDR1 cell system. TSAHC strongly inhibited CYP2C8, CYP2C9, and CYP2C19 isoform activities with $K_i$ values of 0.81, 0.076, and $3.45{\mu}M$, respectively. It also enhanced digoxin accumulation in a dose-dependent manner in the LLCPK1-MDR1 cells. These findings indicate that TSAHC has the potential to inhibit CYP2C isoforms and P-gp activities in vitro. TSAHC might be used as a nonspecific inhibitor of CYP2C isoforms based on its negligible inhibitory effect on other P450 isoforms such as CYP1A2, CYP2A6, CYP2B6, CYP2D6, CYP2E1, and CYP3A.

• 대한한의학회지
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• 제35권2호
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• pp.47-59
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• 2014

Objectives: Most drug interactions are attributed to the inhibition or induction of the activity of cytochrome P450s (CYP450). Although the regulation of CYP450s by drugs has been widely reported, there have been few studies on influence of traditional herbal formulas on the drug-metabolizing enzymes. Because herbal formulas have been used traditionally to treat various diseases and because herb-drug interactions are crucial factors determining therapeutic efficacies, a systematic evaluation of the effects of herbal formulas is important. Methods: The effects of Galgeun-tang (GGT, gegen tang), Gumiganghwal-tang (GMGHT, jiuweiqianghuo tang), Insampaedok-san (ISPDS, renshenbaidu powder), Samsoeum (SSE, shensu drink), Socheongryong-tang (SCRT, xiaoqinglong-tang) and Sosiho-tang (SSHT, xiaochaihu tang) that are traditional herbal formulas used to treat common cold, on drug-metabolizing enzymes were evaluated through an in vitro CYP3A4, CYP2D6, CYP2C19 and CYP2E1 inhibition assay to assess its interaction potential with synthetic drugs. The inhibitory effects of herbal formulas were characterized with $IC_{50}$ values. Results: These six herbal formulas inhibited the activities of CYP3A4, 2C19, 2D6 and 2E1, in a concentration-dependent manner. Among the six herbal formulas, GGT critically inhibited CYP2C19, CYP2D6 and CYP2E1. GMGHT also inhibited CYP2D6 and CYP2E1 to a greater extent than the other CYP450 isozymes. Additionally, SSE and SSHT may change the effects of medicines that depend primarily on the CYP2C19 and CYP2E1 pathways. On the other hand, ISPDS and SCRT were not inhibited CYP3A4, CYP2C19, CYP2D6 and CYP2E1-mediated metabolism. Conclusions: These findings provide useful information regarding the safety and effectiveness of herbal formulas.

• 생명과학회지
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• 제22권8호
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• pp.991-998
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• 2012

인삼 및 인삼 유래 물질들은 가장 대표적인 건강기능식품이며, 홍삼추출물(Panax ginseng C.A. Meyer)의 경우 항바이러스, 알레르기 감소, 항산화, 비만억제 등의 효과를 나타낸다고 알려져 있다. 대표적 건강기능식품임에도 불구하고 약물상호작용을 일으키는 대사효소(Cytochrome P450, CYP)에 대한 홍삼추출물의 영향은 보고되지 않았다. 본 연구에서는 사람의 간 마이크로좀 분획과 마우스 모델을 기반으로 홍삼엑기스의 약물대사 조절능을 평가하였다. 사람의 간 마이크로좀에서는 CYP2B6에 대한 미약한 억제 효과를 나타내었을 뿐, 타 대사효소 CYP1A2, 2B6, 2C19, 2D6와 3A에 대한 억제효과는 검출되지 않았다. 홍삼엑기스를 마우스에 50, 250, or 500 mg/kg의 농도로 3, 7, 14일간 하루 1회 경구 투여 후 간을 적출하여 대사효소의 활성 변화를 측정하였지만, 유의적인 변화는 관찰되지 않았다. 결과적으로 홍삼엑기스의 유의적인 약물대사효소에 대한 활성 조절능이 없는 것으로 판단되고, 홍삼엑기스 복용에 따른 홍삼-약물상호작용의 가능성은 없을 것으로 추정된다.

• Toxicological Research
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• 제12권2호
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• pp.265-270
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• 1996

Effects of a single administration of dichloromethane (DCM) on the hepatic drug metabollzing activity were determined using adult female rats. Rats were treated with DCM (3 mmol/kg, ip) and the disappearance of antipyrine (100 mg/kg, iv) or ethanol (2 g/kg, ip) from blood was measured. The blood concentration and half-life of antipyrine was not influenced by DCM administration. And DCM did not alter the blood concentration of ethanol measured for 240 min after the treatment. The effect of DCM treatment on in vitro cytochrome P-450-dependent enzyme activities was examined as well. No significant difference in either aniline hydroxylase or aminopyrine N-demethylase was observed in hepatic microsomal fractiorts of rats treated with DCM 24 hr prior to sacrifice. The present study indicates that acutely given DCM does not alter the metabolism of xenobiotics in vivo. The failure of DCM to alter the in vitro hepatic microsomal drug metabolizing activity was also noted.

• Environmental Analysis Health and Toxicology
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• 제21권1호
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• pp.13-19
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• 2006

화학적 예방효과가 있는 식물성 에스트로젠은 다양한 환성을 나타내며 여러 세포 수용체와 상호작용한다. Genistein은 isoflavone의 주요물질 중의 하나로 콩류에 존재하며 대표적인 식물성 에스트로젠이다. 본 논문에서는 유방암 세포주인 MCF-7에서 aryl hydrocarbon receptor(AhR)에 의해 매개되는 발암물질 활성화 경로에 대한 genistein의 영향을 살펴보았다. 세포에 genistein을 처리할 경우 cytochrome P450 1A1(CYP1A1) 약물대사효소의 특이적인 효소반응인 7-ethoxyresorufin O-deethylase (EROD) 활성도와 CYP1A1의 유전자 발현이 genistein의 농도 의존적으로 증가하였다. Genistein과 발암물질인 방향족탄화 수소 7, 12-dimethylbenz[a]anthracene(DMBA)를 동시 처리하였을 경우 DMBA에 의해 유도되어 증가된 EROD활성도와 CYP1A1의 유전자 발현이 genistein에 의해 감소하였다. 랫트의 간에서 분리한 세포질을 이용하여 genistein과 AhR의 대표적인 ligand인 2,3,7,8-tetrachlorodibenzo-p-dioxin과 경쟁적 결합에 대한 영향을 조사한 결과 genistein이 AhR에 경쟁적으로 결합함을 알 수 있었다. 이러한 결과들은 genistein이 천연 AhR ligand임을 암시한다. 따라서, 식물성 에스트로젠인 genistein은 AhR경로의 길항제/항진제로 작용할 수 있을 것으로 사료된다.

• Advances in Traditional Medicine
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• 제6권4호
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• pp.274-285
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• 2006

Allium sativum (Family Amaryllidaceae or Liliaceae) is used worldwide for various clinical uses like hypertension, cholesterol lowering effect, antiplatelets and fibrinolytic activity etc. Due to these common house hold uses of Allium sativum, as a herbal supplements, and failure of patients to inform their physician of the over-the-counter supplements they consume leads to drugnutrient interactions with components in herbal supplements. Today these types of interactions between a herbal supplement and clinically prescribed drugs are an increasing concern. In vitro studies indicated that garlic constituents modulated various CYP (cytochrome P450) enzymes. CYP 3A4 is abundantly present in human liver and small intestine and contributes to the metabolism of more than 50% of commonly used drugs including nifedipine, cyclosporine, erythromycin, midazolam, alprazolam, and triazolam. Extracts from fresh and aged garlic inhibited CYP 3A4 in human liver microsomes. The in vivo effects of garlic constituents are found to be species depended and the dosing regimen of garlic constituents appeared to influence the modulation of various CYP isoforms. Studies have indicated that the inhibition of various CYPs by organosulfur compounds from garlic was related to their structure also. Studies using in vitro, in vivo, animal and human models have indicated that various garlic constituents can be the substrates, inhibitors and or inducers of various CYP enzymes. The modulation of CYP enzyme activity and expression are dependent on the type and chemical structure of garlic constituents, dose regime, animal species and tissue, and source of garlic thus this review throws light on the possible herb drug interaction with the use of garlic.

• 한국환경보건학회지
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• 제29권3호
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• pp.9-15
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• 2003

The modification of CYP2El activity is a matter of considerable interest because of its role in the metabolic activation of a variety of environmental toxicants. In the present study, the time-course of changes in human CYP2El activities was determined following treatment with solvents (acetone, dimethylsulphoxide or pyridine) using intact HepG2 cells transfected by human CYP2El. Hydroxylation of chlorzoxazone was used for the measurement of CYP2El activity. CYP2E1 protein level was increased upon cultivation of cells in the presence of the solvents for 24 hr. Determination of CYP2El activities after 24 ht cultivation with the solvents demonstrated that acetone or dimethylsulphoxide increased, whereas pyridine inhibited the activities. This differential effect of the solvents on CYP2El activities persisted to subsequent 24 ht. Competitive inhibition study suggested that pyridine has stronger binding affinity to CYP2E1 than acetone or dimethylsulphoxide. These results demonstrate that different binding affinity of the solvents to CYP2El plays important role in determining real CYP2El activity in intact cells after exposure to the solvents. Present study would be helpful in precise understanding of human CYP2El-mediated toxicity.

• 분석과학
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• 제8권2호
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• pp.117-124
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• 1995

지속적인 음주로 인하여 간경변증으로 사망한 human 간에서 ethanol에 의해서 유도되는 것으로 추측되는 hemoprotein들을 확인 및 부분정제하였다. 이 hemoprotein을 정제하기 위하여 Mohamed 등의 방법을 변형하여 단백질을 정제하였고, SDS-PAGE 및 spectrum 양상을 관찰하였다. Triton N-101을 처리한 crude extract를 준비하여 CO gas를 bubbling시킨 후 Octyl-Sepharose CL-4B column chromatography에서 0.06% Lubrol PX로 용출한 다음 0.25% Lubrol PX로 용출하였다(Fig. 2). 0.06% Lubrol PX로 용출한 active fraction을 Hydroxyapatite와 DEAE-Sephadex A-25 column으로 정제하였다(Fig. 3, 4). 정제한 단백질을 12.5% SDS-PAGE를 실시한 결과 분자량은 대조군으로 사용한 흰쥐 간에서 정제한 단백질의 분자량은 55 KDa와 52 KDa였고, 돌연사한 사람의 간에서 정제한 단백질의 분자량은 62 48KDa이며, 간경변증으로 사망한 사람의 간에서 정제한 단백질의 분자량은 54KDa였고(Fig. 5). Cytochrome P450 함량은 20.8nmol/mg protein이며 회수율은 약 4.1%이고, 이들의 최대흡수 파장은 446nm이었다(Fig. 6).

• Archives of Pharmacal Research
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• 제27권3호
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• pp.319-323
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• 2004

Cytochrome P450 (CYP) 3A4 is of great interest because of its important roles in the oxidation of numerous drugs and xenobiotics. HDJ-1, a molecular chaperone in human, is known to assist the correct folding of unfolded proteins. To achieve a high yield of recombinant human CYP3A4 in Escherichia coli, the CYP3A4 encoding gene was co-expressed with the chaperone HDJ-1, under the control of an inducible tac promoter in a bicistronic format. The levels of expression of the CYP3A4 in the bicistronic construct reached up to 715 nmol $(liter culture)^{-1}$ within 16 h at $37^{\circ}C$, which was about a 3.3-fold increase compared to that of the CYP3A4 alone without the HDJ-1. By co-expression with HDJ-1, the catalytic activity of CYP3A4 was also increased by -15-fold. The amount of activity increase was similar to that of the CYP production at the whole cell level. The present over-expression system may be useful for the rapid production of large amounts of active CYP3A4 in E. coli.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 2003년도 Annual Meeting of KSAP : International Symposium on Pharmaceutical and Biomedical Sciences on Obesity
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• pp.88-88
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• 2003

Cytochrome P-450 3A4 (CYP3A4) is major enzyme in human liver, the role of this is detoxification and metabolizing more than 50% clinical drugs in use. Expression of CYP3A4 is transciptionally regulated by the Pregnenolone X receptor (PXR), of which human form is Steroid and Xenobiotics receptor (SXR). SXR is activated by wide range of endogenous and exogenous compounds, and then induces CYP3A4 gene expression. In the previous study, it has been known that proximal promoter (-864 to +64) does not response to chemical inducers such as pregnenolone 16a-carbonitrile (PCN), Rifampicin, Estrogen in terms of transcription of CYP 3A4 in cultured cells. Here, we developed luciferase reporter gene assay system to detect SXR-based CYP 3A4 transcriptional activity. We have used CYP3A4-Luc plasmid that contains proximal promoter of human CYP3A4 gene upstream of the luciferase gene. We did transient transfection of 3A4-luciferase gene and SXR. In the HepG2 cells transfected with CYP3A4-Luc, when rifampicin treatment was combined with histone deacetylase inhibitor (HDAC Inhibitor), such as Trichostatin A, Hc-toxin and IN 2001 of the luciferase activity was induced 10-20 fold over control.