Genetic analysis of CYP2D6, a drug-metabolizing enzyme for improving pharmacotherapy using evidence-based medicine principles

CYP2D6（一种药物代谢酶，用于利用循证医学原理改善药物治疗）的遗传分析

• 批准号: 12470525
• 负责人: AZUMA Junichi
• 金额: $ 8.13万
• 依托单位: Osaka University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2000
• 资助国家: 日本
• 起止时间: 2000 至 2001
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-12470525/
• 关键词: CYP2D6^*1; CYP2D6^*10; CYP2D6^*36; Expression of CYP2D6^*cDNA; Competitive inhibition; β-blocker; CYP2D6^*5; misjudge; CYP2D6; メキシレチン; CYP2D6*36

In Japanese subjects, we found a significant influence on the pharmacokinetics of venlafaxine by CYP2D6^*10 allele. We hypothesized that the CYP2D6^*10 allele may be a factor in determining interindividual differences in the pharmacokinetics of CYP2D6 substrates. Thus, we conducted this study from this point of view. In clinical study, mexiletine was administered orally to CYP2D6^*1 homozygous subjects and CYP2D6^*10 homozygous subjects. There was no significant difference between the two groups in pharmacokinetics data. But one subject showed higher level of plasma mexiletine concentration than other subjects. We analyzed the genetic structure of CYP2D6 of him and we concluded that it was constructed from twice tandem repeats of CYP2D6^*36. We found the frequency of this genotype was 3 %. CYP2D6.1, CYP2D6.10 and CYP2D6.36 were expressed in yeast cells and their catalytic activities for CYP2D6 substrates, bufurarol and venlafaxine were investigated. The results suggested that the decreased in vivo clearance by CYP2D6^*10 and CYP2D6^*36 was caused not only by low expression of but also increased Km value. We investigated the inhibition of CYP2D6.1, CYP2D6.10 and CYP2D6.36 by β blockers. These inhibitions were all competitive. Ki values show CYP2D6.36>>CYP2D6.10> CYP2D6.1. In patients carrying CYP2D6^*10 or CYP2D6^*36, drug-drug interactions might appear less frequently than in those carrying CYP2D6^*1. In Japanese population allelic frequency of CYP2D6^*5, which results in absence of CYP2D6 enzyme activity, is 4.5 %. It is important to detect CYP2D6^*5 genotype correctly. But we found a new genetic structure of non-CYP2D6^*5 genotype and we are apt to misjudge it as CYP2D6^*5 genotype using conventional long -PCR method for the detection of CYP2D6^*5.

在日本受试者中，我们发现CYP2D6^*10等位基因对文拉法辛的药代动力学有显著影响。我们假设CYP2D6^*10等位基因可能是决定CYP2D6底物药代动力学个体间差异的一个因素。因此，我们从这个角度进行了这项研究。在临床研究中，对CYP2D6^*1纯合子和CYP2D6^*10纯合子受试者口服美西律。两组药代动力学数据无显著性差异。但有1例患者的血浆美西律浓度高于其他患者。我们分析了他的CYP2D6基因的遗传结构，我们认为它是由CYP2D6^*36的两个串联重复序列组成的。我们发现这种基因型的频率为3%。在酵母细胞中表达了CYP2D6.1、CYP2D6.10和CYP2D6.36，并研究了它们对CYP2D6底物丁呋洛尔和文拉法辛的催化活性。结果表明，CYP2D6^*10和CYP2D6^*36的体内清除率降低不仅是由于表达量降低，而且还与Km值升高有关。我们研究了β受体阻滞剂对CYP2D6.1、CYP2D6.10和CYP2D6.36的抑制作用。这些禁忌都是竞争性的。Ki值显示CYP2D6.36>>CYP2D6.10> CYP2D6.1。在携带CYP2D6^*10或CYP2D6^*36的患者中，药物间相互作用的发生率可能低于携带CYP2D6^*1的患者。在日本人群中，导致CYP2D6酶活性缺失的CYP2D6^*5等位基因频率为4.5%。正确检测CYP2D6^*5基因型对临床治疗有重要意义。但我们发现了一种新的非CYP2D6 ^*5基因型的遗传结构，用常规的长链PCR方法检测CYP2D6 ^*5容易将其误判为CYP2D6 ^*5基因型。

项目成果

Nishida, Y. et al.: "CYP2D6 genotypes in a Japanese population, low frequencies of CYP2D6 gene duplication but high frequency of CYP2D6^*10"Pharmacogenetics. 10(6). 567-570 (2000)

Nishida, Y. 等人：“日本人群中的 CYP2D6 基因型，CYP2D6 基因重复频率较低，但 CYP2D6^*10 频率较高”药物遗传学。

Fukuen, S. et al.: "Novol detection assay by PCR-RFLP and frequency of the CYP3A5 SNPs. CYP3A5*3 and *6, in a japanese population"Pharmacogenetics. (in press). (2002)

Fukuen, S. 等人：“日本人群中通过 PCR-RFLP 进行的 Novol 检测分析和 CYP3A5 SNP 的频率。CYP3A5*3 和 *6”药物遗传学。

Fukuda, T. et al: "The decreased in vivo clearance of CYP2D6 substrates by CYP2D6^*10 might be caused not only by the low-expression but also by low affinity of CYP2D6"Arch Biochem Biophys. 380(2). 303-8 (2000)

Fukuda, T. 等人：“CYP2D6^*10 对 CYP2D6 底物的体内清除率降低可能不仅是由于 CYP2D6 的低表达，而且是由于 CYP2D6 的低亲和力造成的”Arch Biochem Biophys。

Fukuen, S. et al: "Novel detection assay by PCR-RFLP and frequency of the CYP3A5 SNPs, CYP3A5*3 and *6, in a Japanese population"Pharmacogenetics. (in press). (2002)

Fukuen, S. 等人：“日本人群中通过 PCR-RFLP 进行的新型检测分析以及 CYP3A5 SNP、CYP3A5*3 和 *6 的频率”药物遗传学。

Igarashi, T. et al: "Effect of calcimimetic agent, KRN568, on gastrin secretion in healthy subjects"Endcr J. 47 (5). 517-23 (2000)

Igarashi, T. 等人：“拟钙剂 KRN568 对健康受试者胃泌素分泌的影响”Endcr J. 47 (5)。