• 생물정신의학
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• 제7권2호
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• pp.140-146
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• 2000

P450 CYP2D6 enzyme(=debrisoquine hydroxylase) is known to metabolize many neuroleptics and some genetic polymorphisms in the CYP2D6 gene were reported to be associated with tardive dyskinesia(TD). We investigeted the association of two genetic polymorphisms in the CYP2D6 gene, $CYP2D6^*4$ and $CYP2D6^*10$, with TD in Korean schizophrenic subjects. Subjects consisted of 71 Korean schizophrenics and TD was evaluated using the Abnormal Involuntary Movement Scale (AIMS). There were no statistically significant differences in the demographic variables of age, male to female percentage and the current antipsychotic(CPZ equivalent) dose between the group with TD and the group without TD. But the duration of antipsychotic drug exposure was significantly higher in the group without TD(p=0.000, by independent t-test). The mean AIMS score in the group with TD was $11.2{\pm}6.6$(S.D.). Genotypings for the presence of $CYP2D6^*4$ and $CYP2D6^*10$ were done using PCR amplifications and endonuclease digestions. There were no statistically significant genotypic and alleleic associations between TD and $CYP2D6^*4$(by chisquare tests), and between TD and $CYP2D6^*10$(by chi-square tests). These results indicate that the $CYP2D6^*4$ and $CYP2D6^*10$ polymorphisms have no significant roles in the causation of TD.

• 약학회지
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• 제59권2호
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• pp.49-54
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• 2015

In the present study we evaluated comparative herb-drug interaction potential of red ginseng total powder, ginsenoside Rg1, and Rb1 by inhibition of CYP isoforms including CYP1A2, CYP2A6, CYP2B6, CYP2C9, CYP2C19, CYP2D6, CYP2E1 and CYP3A4 using pooled human liver microsomes (HLMs). As measured by liquid chromatography-electrospray ionization tandem mass spectrometry, red ginseng total powder inhibited significantly activities of CYP1A2, CYP2A6, CYP2B6, CYP2C9, CYP2C19, CYP2D6, CYP2E1 and testosterone 6-beta hydroxylation by CYP3A4, but the $IC_{50}$ values were higher than $556{\mu}g/ml$. Activities of CYP2B6, CYP2C9, CYP2D6 and CYP3A4 were inhibited by ginsenoside Rb1. Also, activities of CYP1A2, CYP2A6, CYP2B6, CYP2C9, CYP2C19, CYP2D6 and testosterone 6-beta hydroxylation by CYP3A4 were inhibited by ginsenoside Rg1. The $IC_{50}$ values of ginsenoside Rb1 and Rg1 were higher than $200{\mu}g/ml$. Based on $IC_{50}$ values against CYP isoforms, ginsenosides-drug interactions by CYP inhibition may be very low in clinical situations.

• Journal of Preventive Medicine and Public Health
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• 제31권1호
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• pp.1-14
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• 1998

The genetically determined CYP2D6 activity as considered to be associated with cancer susceptibility with inter-individual variation. Genetic polymorphism of CYP2D6(B) and CYP2D6(T) was determined by the two polymerase chain reaction(PCR) and BstN1 and EcoN1 restriction fragment length polymorphisms(RFLP) for 67 lung cancer cases and 95 healthy volunteer controls. The cases were composed of 26 squamous cell carcinoma, 14 small cell carcinoma, 10 adenocarcinoma, 3 large cell undifferentiated carcinoma, and 14 not histologically diagnosed. The results were gained from the 142 subjects (57 cases and 85 controls) who observed successfully in two PCR and BstNl/EcoN1 RELP. Only one and no mutant allele of the CYP2D6(B) and CYP2D6(T) gene was detected, that is, the frequency of mutant allele was very low; 0.7%(1/142) and 0%(0/142), respectively. Detected mutant allele of the CYP2D6(B) was beterozygous type(WM). The odds ratios for lung cancer susceptibility with CYP2D6(B) and CYP2D6(T) genotype were not calculated. These results are similar to the previous understanding that the mutant allele is very rare in Orientals compared to Caucasians, therefore, it considered that CYP2D6(B) and CYP2D6(T) genotypes have maybe no association with lung cancer susceptibility in Koreans. This is the basic data of CYP2D6(B) and CYP2D6(T) genotypes for Koreans. It would be hepful for further study to determine lung cancer susceptibility of Koreans with the data about CYP1A1, CYP2E1, GSTM1 from future study.

• Toxicological Research
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• 제27권1호
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• pp.25-29
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• 2011

The cytochrome P450 (P450, CYP) are the superfamily of heme-containing monooxygenase enzymes, found throughout all nature including mammals, plants, and microorganisms. Mammalian P450 enzymes are involved in oxidative metabolism of a wide range of endo- and exogenous chemicals. Especially P450s involved in drug metabolisms are important for drug efficacy and polymorphisms of P450s in individuals reflect differences of drug responses between people. To study the functional differences of CYP2A6, CYP2D6, and CYP4A11 variants, we cloned the four CYP2A6, three CYP2D6, and three CYP4A11 variants, which were found in Korean populations, in mammalian expression vector pcDNA by PCR and examined their expressions in COS-7 mammalian cells using immunoblots using P450 specific polyclonal antibodies. Three of four CYP2A6, two of three CYP4A11, and two of three CYP2D6 variants showed expressions in COS-7 cells but the relative levels of expressions are remarkably different in those of each variants. Our findings may help to study and explain the differences between functions of CYP variants and drug responses in Korean populations.

• 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.

• Archives of Pharmacal Research
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• 제29권6호
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• pp.525-533
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• 2006

The aim of this study was to evaluate the bioequivalence of risperidone in healthy male subjects representing different CYP2D6 genotypes with respect to risperidone, 9-hydroxyrisperidone (9-OH-risperidone), and active moiety. A total of 506 Korean subjects were genotyped for $CYP2D6^*10$ by means of allele-specific polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Based on the genotype analysis, 24 subjects, 7 homozygous for $CYP2D6^*1$ for $^*10$, and 7 heterozygous for $^*10$, were recruited and received a single oral dose of 2 mg risperidone tablet in this study. Serum concentrations of risperidone and 9-OH-risperidone up to 48 h were simultaneously determined. There were no significant differences of the active moiety, risperidone, and 9-OH-risperidone between the two preparations in AUC_{0-{\propto}}$ and $C_{max}$. The 90% confidence intervals (Cls) for the ratio of means of the log-trans-formed AUC_{0-{\propto}}$ and $C_{max}$ for the active moiety, risperidone, and 9-OH-risperidone were all within the bioequivalence acceptance criteria of 0.80-1.25. The $CYP2D6^*10$ allele particularly was associated with higher serum concentrations of risperidone and the risperidone/9-OH-risperidone ratio compared with the $CYP2D6^*1$ allele. The results demonstrate that the two preparations of risperidone are bioequivalent and it can be assumed that they are therapeutically equivalent and exchangeable in clinical practice. Furthermore, the pharmacokinetic parameters of risperidone and the risperidone/9-OH-risperidone ratio are highly dependent on the CYP2D6 genotypes.

• Asian Pacific Journal of Cancer Prevention
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• 제13권9호
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• pp.4549-4553
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• 2012

This study was designed to investigate the frequency of CYP2D6 polymorphisms and evaluate the association between genetic polymorphisms of CYP2D6 and tamoxifen therapeutic outcome in Thai breast cancer patients. We recruited 48 breast cancer patients who received adjuvant tamoxifen for evaluating CYP2D6 genetic polymorphisms using microarray-based technology. Associations between genotypes-phenotypes and disease free survival were analyzed. Median follow up time was 5.6 years. The mean age of the subjects was 50 years. The 3 common allelic frequencies were 43.8% ($^*10$), 36.5 ($^*1$) and 10.4% ($^*2$) which are related to extensive metabolizer (EM) and intermediate metabolizer (IM) with 70.8% and 29.2 %, respectively. No association between CYP2D6 genotypes and DFS was demonstrated. Nevertheless, exploratory analysis showed statistically significant shorter DFS in the IM group of post-menopause patients (HR, 6.85; 95%CI, 1.48-31.69; P=0.005). Furthermore, we observed statistically significant shorter DFS of homozygous $CYP2D6^*10$ when compared with heterozygous CYP2D6*10 and other genotypes (P=0.005). $CYP2D6^*10$ was the most common genotype in our subjects. Post-menopause patients with homozygous $CYP2D6^*10$ and IM have shorter DFS. To confirm this relationship, larger samples and comprehensively designed trials in Thailand are required.

• 대한한의학회지
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• 제28권1호통권69호
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• pp.51-62
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• 2007

Objectives . The types of Sasang constitutional medicine (SCM) have definite effect on response to herbal drugs. The majority of human P45O dependent xenobiotic metabolism is carried out by polymorphic enzymes which can cause abolished, altered or enhanced metabolism. Therefore, we evaluated the relation of major CYP2C19, 2D6 polymorphism with Sasang types. Methods : 214 healthy subjects were recruited with informed consent; 172 among them had Sasang diagnosis by QSCC2. CYP2D6, 2C19 polymorphism were determined by PCR-RFLP method. Results : None of the Sasang types showed significant difference in CYP2D6, 2C19 polymorphism. However, the Tae-um type showed relatively low frequency of CYP2D6 $^{*}$10/$^{*}$10 polymorphisms with low activity (p=0.110). In the So-yang type, specific $^{*}$3/$^{*}$3 genotype which is a poor metabolizer of CYP2C19$^{*}$3 was detected (p=0.078).Conclusion . These results suggest that the Tae-um type which is said to have high liver function in SCM has the tendency of high drug-metabolizing enzyme activity. With further study, the CYP polymorphism could serve as a scientific tool for SCM diagnosis.

• 약학회지
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• 제46권3호
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• pp.179-184
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• 2002

The abuse of dextromethorphan has been prevalent for 15 years in Korea and its fatal cases were reported even though it has proved to be very safe. In this study, to investigate the safety and tolerance assessment of dextromethorphan, the metabolic phenotyping and genotype of dextromethorphan were studied. After a single 30 mg of dextromethorphan oral administration to 74 volunteers, concentration of dextromethorphan and its metabolites, dextrorphan, hydroxymorphinan and methoxymorphinan were measured in urine which collected during 8hrs after the drug administration. CYP2D6 phenotype was determined from the ratio of dextromethorphan to dextrorphan. GC/MS was used to quantify dextromethorphan and its metabolites. For genotyping, mutant alleles of the CYP2D6 gene were identified. 24 subjects (32.4％) were homozygous for CYP2D6＊10B, 29 subjects (39.2％) were heterozygous for this allele, while in 21 subjects (28.4％) no exon 1 mutation could be found. The frequency of CYP2D6＊10B-allele containing the 188C T mutation was 54％ of total subjects studied.

• Translational and Clinical Pharmacology
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• 제25권3호
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• pp.147-152
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• 2017

This study focused on the role of cytochrome P450 2D6 (CYP2D6) genotypes to predict phenotypes in the metabolism of dextromethorphan. CYP2D6 genotypes and metabolic ratios (MRs) of dextromethorphan were determined in 201 Koreans. Unsupervised clustering algorithms, hierarchical and k-means clustering analysis, and color visualizations of CYP2D6 activity were performed on a subset of 130 subjects. A total of 23 different genotypes were identified, five of which were observed in one subject. Phenotype classifications were based on the means, medians, and standard deviations of the log MR values for each genotype. Color visualization was used to display the mean and median of each genotype as different color intensities. Cutoff values were determined using receiver operating characteristic curves from the k-means analysis, and the data were validated in the remaining subset of 71 subjects. Using the two highest silhouette values, the selected numbers of clusters were three (the best) and four. The findings from the two clustering algorithms were similar to those of other studies, classifying $^*5/^*5$ as a lowest activity group and genotypes containing duplicated alleles (i.e., $CYP2D6^*1/^*2N$) as a highest activity group. The validation of the k-means clustering results with data from the 71 subjects revealed relatively high concordance rates: 92.8% and 73.9% in three and four clusters, respectively. Additionally, color visualization allowed for rapid interpretation of results. Although the clustering approach to predict CYP2D6 phenotype from CYP2D6 genotype is not fully complete, it provides general information about the genotype to phenotype relationship, including rare genotypes with only one subject.