• 한국환경보건학회지
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• 제30권3호
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• pp.230-238
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• 2004

The adverse health effects of a number of environment pollutions are related to the formation of free radicals. Induction of antioxidant defensive system in the response to an oxidative attack is an essential element of the cell to survive. CYP2E1 is easily induced by organic solvents and induces continuous formation of reactive oxygen species (ROS). ${\gamma}$-Glutamyltranspeptidase (${\gamma}$GT) plays an important role in glutathione metabolism and xenobiotic detoxification. To evaluate the characteristic of oxidative stress which induces GGT expression and to understand human antioxidant defensive response against oxidative stress induced by CYP2E1, we studied regulation of ${\gamma}$GT enzyme expression in response to various oxidative stresses in human HepG2 cells. The ${\gamma}$GT activity was not modified after exposure of acute oxidative stress inducing agents (ferric nitrilotriacetate, cumene hydroperoxide, ADP-Fe, O-tetradecanoylphorbol-13-acetate, tumor necrosis factor-alpha). To induce continuous exposure of cells to ROS, HepG2 cells were transfected by human CYP2E1 gene transiently. The CYP2E1 activity was verified with chlorzoxazone hydroxylation. Transfection of CYP2E1 showed continuous 60% increase in intracellular ROS and 240 % increase in microsomal ROS. CYP2E1 overexpressing cells showed increased ${\gamma}$GT activity (2.5-fold). The observed enhancement of ${\gamma}$GT activity correlated with a significant increase of ${\gamma}$GT mRNA (2.1-fold). Treatment with antioxidant strongly prevented the increase in ${\gamma}$GT activity. The CYP2E1 overexpression did not modify toxicity index and increased glutathione levels. These results show that continuous exposure of cells to ROS produced by CYP2E1 up-regulates ${\gamma}$GT; This may be one of the adaptive antioxidant responses of cells to oxidative insult. Present study also suggests that the induction of ${\gamma}$GT could be used as a marker of oxidative stress induced by exposure to organic solvents.

• 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.

• Journal of Pharmaceutical Investigation
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• 제37권6호
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• pp.369-376
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• 2007

Cyclosporine (CsA) and tacrolimus (FK506) have a narrow therapeutic range, and their pharmacokinetic (PK) characteristic varies among individual. They are also substrates for cytochrome P450 (CYP) 3A4, 3A5 genes, and P-glycoprotein, the product of the multidrug resistance 1 (MDR1). The aims were to investigate the relationship between CYP3A and MDR1 genotypes and their PK parameters among healthy subjects. We investigated the genotype for CYP3A and MDR1 gene in human using a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. After oral administration of CsA and FK506 (100 mg and 1 mg, respectively), whole blood samples were taken up to 24 hours. Blood CsA and FK506 concentrations were measured by LC/MS/MS. Each PK parameters were compared using Kruskal-Wallis test according to the CYP3A and MDR1 genotype. We found that the values of AVC for CsA were significantly different among CYP3A5 and MDR1 exon 26 (C3435T) genotypes (P=0.037 and P=0.049). On the other hand, the AUC for FK506 was significantly different only among CYP3A5 genotypes (P=0.013). The results clearly demonstrate the effects of CYP3A5 and MDR1 exon 26 on Cys and FK506 disposition.

• Journal of Nutrition and Health
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• 제36권10호
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• pp.1013-1021
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• 2003

Anemia, the condition of the diminished concentration of hemoglobin per erythrocyte is common in patients with cancer and is a frequent complication of myelosuppressive chemotherapy. Cham-Dang-Gui (Angelicae Gigantis Radix) has been used in traditional Korean medicine to treat hematologic deficiencies. In this study, Cyclophosphamide (CYP), an alkylating agent that has a broad spectrum of anti-cancer activities, was intraperitoneally injected into the experimental animals to suppress the bone marrow thereafter, causing anemia. The hemopoietic effects of Cham-Dang-Gui were examined using anemic rat model. Rats were divided into five groups: CON (control group), ANS (CYP-injected + normal diet), AND (CYP-injected + normal diet + Cham-Dang-Gui), ALS (CYP-injected + low iron diet), and ALD (CYP-injected + low iron diet + Cham- Dang-Gui) groups. CYP (30 mg/kg) was intraperitoneally injected to rats for 3 days to induce anemic condition. Saline or Cham-Dang-Gui was administrated orally during the entire experimental period. CYP injection decreased body weight gain and food consumption in comparison with CON group. Oral administration of Cham-Dang-Gui extract with normal iron diet significantly prevented the lower body weight gain. The blood level of hemoglobin, iron status (serum iron, transferrin, ferritin and TIBC) and blood level of vitamin B-12 in Cham-Dang-Gui treated groups were significantly higher than those of Cham-Dang-Gui untreated groups regardless of amount of iron in the diet. Taken together, it could be concluded that the Cham-Dang-Gui extract could improve anemic condition induced by CYP injection by improving hematological value, iron status and vitamin B12 status in rats.

• Mycobiology
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• 제47권3호
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• pp.301-307
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• 2019

The $11{\alpha}$-hydroxylation of $16{\alpha}$, 17-epoxyprogesterone (EP) catalyzed by Rhizopus nigricans is crucial for the steroid industry. However, lower conversion rate of the biohydroxylation restricts its potential industrial application. The $11{\alpha}$-steroid hydroxylase CYP509C12 from R. oryzae were reported to play a crucial role in the $11{\alpha}$-hydroxylation in recombinant fission yeast. In the present study, the CYP509C12 of R. oryzae (RoCYP) was introduced into R. nigricans using the liposome-mediated mycelial transformation. Heterologous expression of RoCYP resulted in increased fungal growth and improved intracellular reactive oxygen species content in R. nigricans. The $H_2O_2$ levels in RoCYP transformants were approximately 2-folder that of the R. nigricans wild type (RnWT) strain, with the superoxide dismutase activities increased approximately 45% and catalase activities decreased approximately 68%. Furthermore, the $11{\alpha}$-hydroxylation rates of EP in RoCYP transformants (C4, C6 and C9) were 39.7%, 38.3% and 38.7%, which were 12.1%, 8.2% and 9.4% higher than the rate of the RnWT strain, respectively. This paper investigated the effect of heterologous expression of RoCYP in R. nigricans, providing an effective genetic method to construct the engineered strains for steroid industry.

• 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.

• Biomolecules & Therapeutics
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• 제30권6호
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• pp.510-519
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• 2022

Tofacitinib, a Janus kinase 1 and 3 inhibitor, is mainly metabolized by CYP3A1/2 and CYP2C11 in the liver. The drug has been approved for the chronic treatment of severe ulcerative colitis, a chronic inflammatory bowel disease. This study investigated the pharmacokinetics of tofacitinib in rats with dextran sulfate sodium (DSS)-induced ulcerative colitis. After 1-min of intravenous infusion of tofacitinib (10 mg/kg), the area under the plasma concentration-time curves from time zero to time infinity (AUC) of tofacitinib significantly increased by 92.3%. The time-averaged total body clearance decreased significantly by 47.7% in DSS rats compared with control rats. After the oral administration of tofacitinib (20 mg/kg), the AUC increased by 85.5% in DSS rats. These results could be due to decreased intrinsic clearance of the drug caused by the reduction of CYP3A1/2 and CYP2C11 in the liver and intestine of DSS rats. In conclusion, ulcerative colitis inhibited CYP3A1/2 and CYP2C11 in the liver and intestines of DSS rats and slowed the metabolism of tofacitinib, resulting in increased plasma concentrations of tofacitinib in DSS rats.

• Clinical and Experimental Reproductive Medicine
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• 제48권4호
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• pp.347-351
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• 2021

Objective: We investigated the impact of vitamin D₃ (VD3) supplementation during mouse preantral follicle culture in vitro and the mRNA expression of 25-hydroxylase (CYP2R1), 1-alpha-hydroxylase (CYP27B1), and vitamin D receptor (VDR) in mouse ovarian follicles at different stages. Methods: Preantral follicles were retrieved from 39 BDF1 mice (7-8 weeks old) and then cultured in vitro for 12 days under VD3 supplementation (0, 25, and 50 pg/mL). Follicular development and the final oocyte acquisition were assessed. Preantral follicles were retrieved from 15 other BDF1 mice (7-8 weeks old) and cultured without VD3 supplementation. Three stages of mouse ovarian follicles were obtained (preantral, antral, and ruptured follicles). Total RNA was extracted from the pooled cells (from 20 follicles at each stage), and then reverse transcriptase-polymerase chain reaction was performed to identify mRNA for CYP2R1, CYP27B1, and VDR. Results: The survival of preantral follicles, rates of antrum formation and ruptured follicles (per initiated follicle) and the number of total or mature oocytes were all comparable among the three groups. Both CYP2R1 and CYP27B1 were expressed in antral and ruptured follicles, but not in preantral follicles. VDR was expressed in all three follicular stages. Conclusion: VD3 supplementation in vitro (25 or 50 pg/mL) did not enhance mouse follicular development or final oocyte acquisition. Follicular stage-specific expression of CYP2R1, CYP27B1, and VDR was observed.

• Journal of Microbiology and Biotechnology
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• 제33권3호
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• pp.387-397
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• 2023

Cytochrome P450 (CYP) is a heme-containing enzyme that catalyzes hydroxylation reactions with various substrate molecules. Steroid hydroxylases are particularly useful for effectively introducing hydroxyl groups into a wide range of steroids in the pharmaceutical industry. This study reports a newly identified CYP steroid hydroxylase (BaCYP106A6) from the bacterium Bacillus sp. and characterizes it using an in vitro enzyme assay and structural investigation. Bioconversion assays indicated that BaCYP106A1 catalyzes the hydroxylation of progesterone and androstenedione, whereas no or low conversion was observed with 11β-hydroxysteroids such as cortisol, corticosterone, dexamethasone, and prednisolone. In addition, the crystal structure of BaCYP106A6 was determined at a resolution of 2.8 Å to investigate the configuration of the substrate-binding site and understand substrate preference. This structural characterization and comparison with other bacterial steroid hydroxylase CYPs allowed us to identify a unique Arg295 residue that may serve as the key residue for substrate specificity and regioselectivity in BaCYP106A6. This observation provides valuable background for further protein engineering to design commercially useful CYP steroid hydroxylases with different substrate specificities.

• 한국식품영양과학회지
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• 제34권5호
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• pp.573-580
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• 2005

수용성 식이섬유의 섭취는 혈청 콜레스테롤 저하효과가 있으며 , 그 작용기 작으로는 수용성 식이섬유의 점성으로 인한 콜레스테롤과 담즙산 흡수저해, 대장내 미생물 발효로 생성 된 단쇄지방산에 의한 콜레스테롤 합성률 변경 및 담즙산 합성증가 등으로 설명되어진다. 그러나 명확한 작용기전은 규명 되지 않았다. 본 연구에서는 간세포 핵내의 CYP7A1의 발현에 호르몬과 식이섬유의 발효로 생성된 단쇄지방산이 미치는 영향을 알아보았다. 사람의 간세포(HepG2 세포)의 배양배지에 insulin, dexamethasone 및 triiodothyronine을 각각 $1\;{\mu}M$ 투여하고 24시간 배양하였다. Semi-quantitative RT-PCR기법에 의해 CYP7A1 mRNA발현을 측정한 결과, dexamethasone에서 가장 높아 $173\%$의 증가를 나타내었고, 그 다음으로 insulin에서 $150\%$, triiodothyronine 에서 $141\%$의 증가를 나타내었다. 이처럼 transient transfection을 하지 않은 HepG2 세포에서 생리적 조절자로 알려진 insulin, dexamethasone 및 triiodothyronine이 CYP7A1의 발현을 모두 증가시킨다는 결과는 본 연구에서 처음으로 규명하며, rat gene and/or human gene 발현이 다르게 조절됨을 제안한다. 단쇄지방산에 의한 HepG2 세포에서의 CYP7A1 유전자의 발현 정도를 측정하기 위해서 actetate, propionate 및 butyrate를 각각 1 M농도로 24시간 동안 배양한 결과, 모든 단쇄지방산이 CYP7A1의 발현을 증가시켰다. Acetate와 propionate는 유사한 효과를 나타내어 대조군에 비하여 1.8배의 증가를 나타내었으며 , butyrate는 1.5배의 증가를 보였다. 이상의 결과는 수용성 식이섬유 섭취시 나타나는 콜레스테롤 저하 효과는 수용성 식이섬유의 대장 발효가 대장을 자극함으로써 내인성 호르몬의 변화를 통해서 나타나거나 대장내 발효산물인 actetate, propionate 및 butyrate 등이 흡수되어 간에서의 CYP7A1의 up-regulation에 의한 담즙산 배설증가에 따른 결과로 설명할 수 있을 것이다. 단쇄지방산의 CYP7A1 발현에 미치는 작용은 acetate와 propionate가 butyrate보다 큼을 알 수 있었다.