• 한국환경성돌연변이발암원학회:학술대회논문집
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• 한국환경성돌연변이발암원학회 2003년도 추계학술대회
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• pp.166-166
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• 2003

• 생약학회지
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• 제37권2호통권145호
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• pp.97-102
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• 2006

Garlic(Allium sativum Linn) is widely used as a common condiment for a variety of foods and beverages. It has been well known that fresh garlic and garlic supplement of commercial preparations have various therapeutic properties including antimicrobial activity, antiplatelet aggregation, antihypertension, and cholesterol-lowering effects, which contribute to its increasing uses for an alternative medicine. Allicin(diallyl thiosulfinate), the major bioactive components of garlic, is formed by alliinase cleavage of the naturally occurring alliin upon crushing or mincing of garlic, and is the progenitor of a number of other products, such as diallyl disulfide. CYP3A4, heme-containing monooxygenase, is a key enzyme responsible for drug metabolism. Therefor, in the present study, we isolated and examined the compounds with CYP3A4-inhibiting activities from garlic. Among EtOAc extracts of garlic, we found that N-p-coumaroyltyramine and N-feruloyltyramine showed remarkable CYP3A4-inhibiting activities, compared to diallyl disulfide. Structures of the isolated active compounds were established by chemical and spectroscopic means.

• Molecular & Cellular Toxicology
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• 제2권4호
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• pp.262-265
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• 2006

We report a case of phenytoin toxicity due to impaired drug metabolism in a patient homozygous for $CYP2C9^{\ast}3$. A 46-year-old woman was taking phenytoin to prevent postoperative seizures. She attained high serum phenytoin levels at the standard doses (300 mg/day) and developed symptoms of phenytoin toxicity including blurred vision, nausea and headache. The patient was treated with reduced doses of phenytoin and then phenytoin therapy was finally discontinued. Genotyping for CYP2C9 revealed that this patient had a homozygous genotype, $CYP2C9^{\ast}3/^{\ast}3$. This is the first Korean case of phenytoin toxicity with homozygous $CYP2C9^{\ast}3$. This case suggests the clinical usefulness of pharmacogenetic testing for individualized dosage adjustments of phenytoin.

• BMB Reports
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• 제45권12호
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• pp.736-741
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• 2012

Certain members of the cytochromes P450 superfamily metabolize polyunsaturated long-chain fatty acids to several classes of oxygenated metabolites. An approach based on in silico analysis predicted that Streptomyces peucetius CYP107N3 might be a fatty acid-metabolizing enzyme, showing high homology with epoxidase enzymes. Homology modeling and docking studies of CYP107N3 showed that oleic acid can fit directly into the active site pocket of the double bond of oleic acid within optimum distance of $4.6{\AA}$ from the Fe. In order to confirm the epoxidation activity proposed by in silico analysis, a gene coding CYP107N3 was expressed in Escherichia coli. The purified CYP107N3 was shown to catalyze $C_9-C_{10}$ epoxidation of oleic acid in vitro to 9,10-epoxy stearic acid confirmed by ESI-MS, HPLC-MS and GC-MS spectral analysis.

• 생물정신의학
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• 제8권2호
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• pp.208-219
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• 2001

The pharmacotherapy of schizophrenia exhibits wide inter-individual variabilities in clinical efficacy and adverse effects. Recently, human genetic diversity has been known as one of the essential factors to the variation in human drug response. This suggests that drug therapy should be tailored to the genetic characteristics of the individual. Pharmacogenetics is the field of investigation that attempts to elucidate genetic basis of an individual's responses to pharmacotherapy, considering drug effects divided into two categories as pharmacokinetics and pharmacodynamics. The emerging field of pharmacogenomics, which focuses on genetic determinants of drug response at the level of the entire human genome, is important for development and prescription of safer and more effective individually tailored drugs and will aid in understanding how genetics influence drug response. In schizophrenia, pharmacogenetic studies have shown the role of genetic variants of the cytochrome P450 enzymes such as CYP2D6, CYP2C19, and CYP2A1 in the metabolism of antipsychotic drugs. At the level of drug targets, variants of the dopamine $D_2$, $D_3$ and $D_4$, and 5-$HT_{2A}$ and 5-$HT_{2C}$ receptors have been examined. The pharmacogenetic studies in schizophrenia presently shows controversial findings which may be related to the multiple involvement of genes with relatively small effects and to the lack of standardized phenotypes. For further development in the pharmacogenomics of schizophrenia, there would be required the extensive outcome measures and definitions, and the powerful new tools of genomics, proteomics and so on.

• 한국임상약학회지
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• 제22권1호
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• pp.1-8
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• 2012

항혈소판제인 티크로피딘과 항고혈압제인 니칼디핀과의 약동학적 상호작용 연구를 위하여 티크로피딘 (3 또는 10 mg/kg)과 니칼디핀의 경구 (4 mg/kg) 및 정맥 (12 mg/kg) 투여하여 본 연구를 시행하였다. 연구방법: 티크로피딘이 cytochrome P450 (CYP) 3A4 활성과 P-glycoprotein (P-gp)의 활성에 미치는 영향도 평가하였다. 결 과: 티크로피딘과 니칼디핀의 병용투여 시 티크로피딘이 니칼디핀의 약물동태 파라미터에 미치는 결과는 다음과 같다. 티크로피딘은 CYP3A4 효소의 활성을 저해 하였으나 P-gp활성에는 영향을 미치지 못하였다. 니칼디핀의 혈중농도곡선하면적 (AUC)는 대조군에 비해 티크로피딘 10 mg/kg 병용투여군에서 유의성 (p < 0.05)있게 증가되었다. 상대적 생체이용률 (RB)은 티크로피딘 병용투여군에서 115-143%로 증가하였다. 결 론: 본 논문에서 흰쥐에 티크로피딘과 니칼디핀을 병용경구투여 시 니칼디핀의 생체이용률 (bioavailability)이 유의성 (p < 0.05)있게 증가된 것은 티크로피딘이 대사효소인 CYP3A4를 억제하여 소장과 간장에서 초회통과효과 (first-pass metabolism)를 감소 시켰기 때문인 것으로 사료된다. 본 실험결과를 토대로 인체에서 티크로피딘과 니칼디핀의 상호작용을 검토한 후 투여용량을 조절하는 것이 바람직하다고 사료된다.

• 약학회지
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• 제55권4호
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• pp.332-337
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• 2011

The purpose of this study was to investigate the effect of epigallocatechin gallate (EGCG) on the pharmacokinetics of nimodipine in rats. Pharmacokinetic parameters of nimodipine were determined in rats after oral and iv administration of nimodipine with or without EGCG and also the effect of EGCG on the cytochrome P450 (CYP) 3A4 and P-glycoprotein (P-gp) activity were evaluated. EGCG inhibited CYP3A4 and P-gp activity. EGCG significantly increased the area under the plasma concentration-time curve (AUC) and peak plasma concentration ($C_{max}$) of nimodipine. The absolute bioavailability (AB%) and relative bioavailability (RB%) of nimodipine by EGCG were increased by 16% and by 48%, respectively, compared to the control. In contrast, EGCG did not affect the intravenous pharmacokinetics of nimodipine. Based on these results, the increased bioavailability of nimodipine might be due to inhibition of CYP3A4 in the small intestine and/or in the liver and inhibition of P-gp in the small intestine by EGCG.

• 한국임상약학회지
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• 제21권2호
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• pp.115-121
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• 2011

에토포시드와 아피제닌의 약동학적 상호작용 연구를 위하여 아피제닌 (0.4, 2.0 또는 8 mg/kg)과 에토포시드의 경구(6 mg/kg) 및 정맥 (2 mg/kg) 투여 하여 본 연구를 실시하였다. 아피제닌이 cytochrome P450 (CYP) 3A4 활성과 P-glycoprotein (P-gp)의 활성에 미치는 영향도 평가하였다. 아피제닌의 CYP3A4의 50% 효소활성억제는 $1.8{\mu}M$ 이었다. 아피제닌은 MCF-7/ADR 세포의 로다마인-123 세포 축적을 증가 시키므로 P-gp를 억제시켰다. 아피제닌은 에토포시드의 혈장곡선하면적과 최고혈장농도 (AUC and $C_{max}$)를 유의성 있게 증가시켰으나, 에토포시드의 최고혈장농도 도달시간 ($T_{max}$)과 생물학적 반감기 ($t_{1/2}$)에는 영향을 미치지 않았다. 따라서, 아피제닌 존재하에 에토포시드의 절대적생체이용률 (AB)은 대조군과 비교하여 유의성있게 증가되었다. 경구투여시와는 대조적으로, 아피제닌은 정맥 내로 투여된 에토포시드에서는 약동학적 파라미터에 어떤 영향도 미치지 않았다. 따라서 아피제닌이 에토포시드의 생체이용률을 증가시킨 것은 아피제닌이 소장과 간장에서 CYP3A4을 억제 및 소장에서 P-gp를 억제 시켰기 때문으로 사료된다.

• Journal of Korean Medical Science
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• 제33권53호
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• pp.298.1-298.10
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• 2018

Background: The renal function of individuals is one of the reasons for the variations in therapeutic response to various drugs. Patients with renal impairment are often exposed to drug toxicity, even with drugs that are usually eliminated by hepatic metabolism. Previous study has reported an increased plasma concentration of indoxyl sulfate and decreased plasma concentration of $4{\beta}$-hydroxy (OH)-cholesterol in stable kidney transplant recipients, implicating indoxyl sulfate as a cytochrome P450 (CYP) inhibiting factor. In this study, we aimed to evaluate the impact of renal impairment severity-dependent accumulation of indoxyl sulfate on hepatic CYP3A activity using metabolic markers. Methods: Sixty-six subjects were enrolled in this study; based on estimated glomerular filtration rate (eGFR), they were classified as having mild, moderate, or severe renal impairment. The plasma concentration of indoxyl sulfate was quantified using liquid chromatography-mass spectrometry (LC-MS). Urinary and plasma markers ($6{\beta}$-OH-cortisol/cortisol, $6{\beta}$-OH-cortisone/cortisone, $4{\beta}$-OH-cholesterol) for hepatic CYP3A activity were quantified using gas chromatography-mass spectrometry (GC-MS). The total plasma concentration of cholesterol was measured using the enzymatic colorimetric assay to calculate the $4{\beta}$-OH-cholesterol/cholesterol ratio. The correlation between variables was assessed using Pearson's correlation test. Results: There was a significant negative correlation between MDRD eGFR and indoxyl sulfate levels. The levels of urinary $6{\beta}$-OH-cortisol/cortisol and $6{\beta}$-OH-cortisone/cortisone as well as plasma $4{\beta}$-OH-cholesterol and $4{\beta}$-OH-cholesterol/cholesterol were not correlated with MDRD eGFR and the plasma concentration of indoxyl sulfate. Conclusion: Hepatic CYP3A activity may not be affected by renal impairment-induced accumulation of plasma indoxyl sulfate.

• Biomolecules & Therapeutics
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• 제23권5호
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• pp.486-492
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• 2015

Drug metabolism mostly occurs in the liver. Cytochrome P450 (CYP) is a drug-metabolizing enzyme that is responsible for many important drug metabolism reactions. Recently, the US FDA and EU EMA have suggested that CYP enzyme induction can be measured by both enzymatic activity and mRNA expression. However, these experiments are time-consuming and their interassay variability can lead to misinterpretations of the results. To resolve these problems and establish a more powerful method to measure CYP induction, we determined CYP induction by using luminescent assay. Luminescent CYP assays link CYP enzyme activity to firefly luciferase luminescence technology. In this study, we measured the induction of CYP isozymes (1A2, 2B6, 2C9, and 3A4) in cryopreserved human hepatocytes (HMC424, 478, and 493) using a luminometer. We then examined the potential induction abilities (unknown so far) of mesalazine, a drug for colitis, and mosapride citrate, which is used as an antispasmodic drug. The results showed that mesalazine promotes CYP2B6 and 3A4 activities, while mosapride citrate promotes CYP1A2, 2B6, and 3A4 activities. Luminescent CYP assays offer rapid and safe advantages over LC-MS/MS and qRT-PCR methods. Furthermore, luminescent CYP assays decrease the interference between the optical properties of the test compound and the CYP substrates. Therefore, luminescent CYP assays are less labor intensive, rapid, and can be used as robust tools for high-throughput CYP screening during early drug discovery.