中国汉族人群S-美芬妥英4'-羟化酶的表型与基因分析

目的：研究中国汉族人群S-美芬妥英4'-羟化代谢遗传多态性。方法：以美芬妥英为探针药物采用手性毛细管气相色谱法测定尿中S-/R-MP浓度比值, 对90名志愿者进行了表型分型测定,应用PCR技术对其中的26名志愿者进行了S-美芬妥英4'-羟化酶（CYP2C19）基因分析。结果：表型分析结果,11人属慢代谢者（PM）,S/R比值0.95;基因分析结果,6人为野生型纯合子（wt/wt）;10人为杂合子（wt/m₁和wt/m₂）,9人为CYP2C19m₁突变型纯合子（m₁/m₁）,1人为两突变型杂合子（m₁/m₂）。结论：表型分析与基因分析结果显示了很好的相关性,本实验测得慢代谢者的频发率为12.2%,与文献报道相符。     

高效液相色谱法测定尿中美芬妥英及代谢产物4'-羟基美芬妥英

A simple, sensitive and reproducible HPLC assay is described for the determination of mephenytoin and 4'-hydroxymephenytoin in human urine. Phenobarbital was used as an internal standard.The compounds were separated on a U-Bondapack RP-C₁₈ column using a mobile phase of and the UV detectou was set at 210 nm. Calibration curves in the range 0.05～1.00ug/ml for mephenytoin and 0.5～100.0ug/ml for 4'-hydroxymephenytoin were linear (r=0.9998and r=0.9992,respectivesy). The average recovery was 95.10±2。95%,and the relative standard devia- tion within day and day to day was less than 10%。The detection limit for mephenytoin was 25mg/ml and 4‘-hydroxymephenytoin was 50mg。ml。The method was used to study the metabolism of S-mephenytoin 4'-hydroxylatoin in 10healthy volunteers.The 12 h urinary metabolic ratio (MR)and hydroxylation index(HI)were calculated to express interindividual variation in metabolism. Two of them exhibited defective 4'-hydroxylation of S-mephenytoin as poor metabllizers (HI:1349.18 and 409.57;MR:105.29 and 8.25).In the remaining 8 subjects, the ranged from 1.68 to 6.71 and the MR ranged from 0.002 to 0.014,as extensive metabolizers of S-mephenytoin.     

中国汉族人S-美芬妥英4′-羟化代谢的遗传多态性(英文)

目的:研究我国汉族人S-美芬妥英(S-Mep)4′-羟化代谢的遗传多态性。方法:148名互无血缘关系的汉族健康志愿者和5个家族21名成员,口服美芬妥英100mg后,用HPLC法测定0-12h尿中S-Mep 4′-羟化代谢的代谢比值(lg MR)和羟化指数(lg HI)。结果:lg MR和lg HI均呈两态性分布,分型点(antimode)分别为-1.00和1.50,羟化代谢缺陷的频发率为13.5％(20/148)。系谱分析表明S-Mep 4′-羟化代谢缺陷为常染色体隐性遗传。结论:S-Mep 4′-羟化代谢缺陷频发率东方人高于高加索人,遗传方式均为常染色体隐性遗传。     

高效液相色谱法测定尿中美芬妥英及代谢产物4＇－羟基美芬妥英

高效液相色谱法测定尿中美芬妥英及代谢产物４＇－羟基美芬妥英阮邹荣，程源深，丁德云（浙江医科大学附属第二医院临床药理研究所３１０００９）美芬妥英（ｍｅｐｈｅｎｙｔｏｉｎ，ＭＰ）化学名为３－甲基－５－苯基－５－乙基乙内酰脲（３－ｍｅｔｈｙｌ－５－ｐｈｅｎ...     

中国汉族人S—美芬妥英4‘—羟化代谢的遗传多态性

研究我国汉族人Ｓ－美芬妥英４＇－羟化代谢的遗传多态性。１４８名互无血缘关系的汉族健康志愿者和５个家庭２１名成员，口服美芬妥英１００ｍｇ后，用ＨＰＬＣ法测定０－１２ｈ尿中Ｓ－Ｍｅｐ４＇－羟化代谢的代谢比值和羟化指数。     

中国人S—美芬妥英／奥美拉唑羟化代谢多态性的分子机制探讨

为探讨中国人Ｓ－美芬妥英／奥美拉唑氧化代谢多态性的分子机制，本文用多聚酶链式反应方法扩增出ＣＹＰ２Ｃ１９ｉｎｔｒｏｎ４／ｅｘｏｎ５特异的ＤＮＡ片段，并用限制性内切酶ＳｍａＩ进行酶切分析。研究结果表明，１６位健康志愿者的ＣＹＰ２Ｃ１９存在ＳｍａＩ酶切位点的多态性，且与Ｓ－ＭＰ羟化代谢表型有相关性。     

中国人群中CYP2C19活性的个体和种族差异(英文)

本文综述了我国,其中主要在我们实验室,近年来对CYP2C19的研究结果,包括中国人群中多个民族之间CYP2C19的遗传多态性分布及活性比较;中国多个民族中CYP2C19遗传多态性的分子机制;一些非遗传因素对CYP2C19活性的影响;以及CYP2C19在一些重要药物代谢中的作用。     

CYP2C9基因多态性与合理用药研究

细胞色素P4502C9(Cytochrome P4502C9,CYP2C9)基因编码蛋白在人类肝细胞微粒体中含量丰富,约占CYP总量的20%,仅次于CYP3A。CYP2C9能代谢许多不同性质的药物,并在前致癌物、前毒物和致突变剂的活化中也起到一定作用。1993年,国外从一个S-美芬妥英强代谢个体中分离出CYP2C9基因并     

Functional characterization of two novel CYP2C19 variants (CYP2C19*18 and CYP2C19*19) found in a Japanese population

Cytochrome P450 2C19 (CYP2C19) plays an important role in the metabolism of a wide range of therapeutic drugs and exhibits genetic polymorphism with interindividual differences in metabolic activity. We have previously described two CYP2C19 allelic variants, namely CYP2C19*18 and CYP2C19*19 with Arg329His/Ile331Val and Ser51Gly/Ile331Val substitutions, respectively. In order to investigate precisely the effect of amino acid substitutions on CYP2C19 function, CYP2C19 proteins of the wild-type (CYP2C19.1B having Ile331Val) and variants (CYP2C19.18 and CYP2C19.19) were heterologously expressed in yeast cells, and their S-mephenytoin 4'-hydroxylation activities were determined. The K(m) value of CYP2C19.19 for S-mephenytoin 4'-hydroxylation was significantly higher (3.0-fold) than that of CYP2C19.1B. Although no significant differences in V(max) values on the basis of microsomal and functional CYP protein levels were observed between CYP2C19.1B and CYP2C19.19, the V(max)/K(m) values of CYP2C19.19 were significantly reduced to 29-47% of CYP2C19.1B. By contrast, the K(m), V(max) or V(max)/K(m) values of CYP2C19.18 were similar to those of CYP2C19.1B. These results suggest that Ser51Gly substitution in CYP2C19.19 decreases the affinity toward S-mephenytoin of CYP2C19 enzyme, and imply that the genetic polymorphism of CYP2C19*19 also causes variations in the clinical response to drugs metabolized by CYP2C19.     

Functional characterization of two novel CYP2C19 variants (CYP2C19*18 and CYP2C19*19) found in a Japanese population

Cytochrome P450 2C19 (CYP2C19) plays an important role in the metabolism of a wide range of therapeutic drugs and exhibits genetic polymorphism with interindividual differences in metabolic activity. We have previously described two CYP2C19 allelic variants, namely CYP2C19*18 and CYP2C19*19 with Arg329His/Ile331Val and Ser51Gly/Ile331Val substitutions, respectively. In order to investigate precisely the effect of amino acid substitutions on CYP2C19 function, CYP2C19 proteins of the wild-type (CYP2C19.1B having Ile331Val) and variants (CYP2C19.18 and CYP2C19.19) were heterologously expressed in yeast cells, and their S-mephenytoin 4′-hydroxylation activities were determined. The K_m value of CYP2C19.19 for S-mephenytoin 4′-hydroxylation was significantly higher (3.0-fold) than that of CYP2C19.1B. Although no significant differences in V_max values on the basis of microsomal and functional CYP protein levels were observed between CYP2C19.1B and CYP2C19.19, the V_max/K_m values of CYP2C19.19 were significantly reduced to 29–47% of CYP2C19.1B. By contrast, the K_m, V_max or V_max/K_m values of CYP2C19.18 were similar to those of CYP2C19.1B. These results suggest that Ser51Gly substitution in CYP2C19.19 decreases the affinity toward S-mephenytoin of CYP2C19 enzyme, and imply that the genetic polymorphism of CYP2C19*19 also causes variations in the clinical response to drugs metabolized by CYP2C19.     

等位基因特异扩增法研究中国人CYP2D6中速代谢的相关基因

目的　建立CYP2D6*10B的等位基因特异扩增法(ASA-PCR),以探讨中国人CYP2D6中速代谢的基因分型。方法　采用两步扩增法得到CYP2D6*10B等位基因特异片段,分析健康中国汉族人CYP2D6*10B等位基因,并探讨基因分型结果与右美沙芬表型分型结果的相关性。结果　35名表型为极快代谢受试者(VEMs)中,CYP2D6*10B以杂合子(wt/m)为主占57%;29名中速代谢受试者(IMs)以突变型纯合子(m/m)为主占69%;慢代谢受试者(PM)基因型为m/m。CYP2D6*10Bm/m组的MR明显大于wt/m组和野生型组(wt/wt)。结论　ASA-PCR法有快速、准确的优点,可用于CYP2D6中速代谢的检测与研究。     

中国人群难治性癫痫患者CYP2C19*2基因型对癫痫耐药的影响

目的:研究中国人群难治性癫痫患者CYP2C19*2基因型对癫痫耐药的影响,促进阐明难治性癫痫的耐药机制。方法:采用聚合酶链反应(PCR)-限制性片段长度多态性(RFLP)方法对难治性癫痫患者(接受癫痫治痫灶切除的患者)和非难治性癫痫患者(单药有效的癫痫患者)的CYP2C19*2(681G→A)位点进行基因型分析,对患者杂合型和纯突变型的样本进行抽样测序验证,以确保基因分型结果准确。对两组基因和基因型频率采用卡方检验的统计学分析,选用SPSS12.0版软件进行处理。结果:收集了96例难治性癫痫患者和305例非难治性癫痫患者。CYP2C19*2等位基因频率:难治组G64.6%,A35.4%;非难治组:G67.9%,A32.1%;难治组突变基因频率高于非难治组但没有统计学差异(P>0.05)。CYP2C19*2基因型频率:难治组GG33.3%,GA62.5%,AA4.2%;非难治组GG44.6%,GA46.6%,AA8.9%。难治组和非难治组基因型频率具有统计学差异(P<0.05),难治组中GG型频率显著低于非难治组,GA型频率高于非难治组(P<0.05);而AA型频率在两组内虽然不同却没有统计学差异。另外,进行基因型组合后,只有无突变(GG)与突变(GA和AA)基因型频率在两组间有统计学差异(P<0.05),难治组突变基因型频率高于非难治性组(66.7%:55.4%)。结论:中国人群难治性癫痫患者与非难治性癫痫患者的CYP2C19*2基因型分布频率有统计学差异,难治性癫痫组CYP2C19*2突变基因型频率高于非难治组;癫痫耐药与CYP2C19*2基因型之间没有关联性,阐明癫痫耐药机制应更加关注多基因之间的联合作用尤其是影响脑组织局部药物浓度的基因。     

盐酸纳曲酮对阿片类成瘾脱毒后防止复发效能的再评价──1088例纳曲酮维持治疗临床研究

目的··:就盐酸纳曲酮防止阿片类成瘾脱毒后复发的效能进行再评价。方法··:1088例完成脱毒治疗的海洛因依赖者给予纳曲酮治疗。药物剂量相对固定在40-50mg·d-1,并随患者反应调整。治疗期间定期门诊或出诊随访。结·果·:服用纳曲酮6个月的保持率为33.4%,与自身同期操守率(2.4%)比较具有显著性差异。服用纳曲酮后,再吸海洛因的欣快感、渴求程度及偶吸海洛因的发生率均降低。纳曲酮的不良反应轻,包括:睡眠障碍、消化系统症状和乏力,少数患者转氨酶呈一过性增高。在纳曲酮治疗的同时给予积极的家庭支持和社会帮教,提供生活和就业技能的指导,减少偶吸的机会等措施,有助于提高服药保持时间。结论··:进一步证实了纳曲酮对预防我国阿片类依赖者脱毒后复吸具有肯定的辅助治疗作用。     

Genetic polymorphism of debrisoquine (CYP2D6) and proguanil (CYP2C19) in South Pacific Polynesian populations

Objective: Genetic oxidation polymorphisms of debrisoquine (CYP2D6) and proguanil (CYP2C19) were studied in unrelated healthy South Pacific Polynesian volunteers recruited in the South Island of New Zealand. Methods: Phenotyping for CYP2D6 and CYP2C19 activities was determined using debrisoquine and proguanil, respectively, as probe drugs by measuring the urinary metabolic ratio of parent drug and its␣metabolite. Results: Of 100 Polynesian subjects phenotyped, the metabolic ratio of debrisoquine ranged from 0.01 to 9.94. Therefore, all South Pacific Polynesians were classified as extensive metabolizers of debrisoquine according to previously established criteria of the antimode. The prevalence of poor metabolizers of debrisoquine (CYP2D6) in this Polynesian population is 0% (95% confidence interval of 0–3.6%). Oxidation polymorphism of CYP2C19 using proguanil as a probe was also studied in 59 Polynesian volunteers. The frequency distribution of the proguanil/cycloguanil ratio was bimodal. The proguanil/cycloguanil ratios for these subjects ranged from 0.09 to 34.4. Using a recommended proguanil/cycloguanil ratio cut-off point of 10 established in Caucasian populations, eight Polynesian subjects were identified as poor metabolizers of proguanil (CYP2C19), which corresponds to a poor metabolizer phenotype frequency of 13.6% (a 95% confidence interval of 5.9–24.6%). Conclusion: The incidence of poor metabolizer phenotypes for debrisoquine (CYP2D6) in South Pacific Polynesians appears to lower than in Caucasian populations, while the prevalence of poor metabolizers for proguanil (CYP2C19) in this ethnic population is higher. The frequencies of the poor metabolizer phenotype for debrisoquine and also for proguanil in South Pacific Polynesians are similar to those reported in Asian populations. Received: 18 December 1997 / Accepted in revised form: 30 April 1998     

Genetic polymorphisms of CYP2C9 and CYP2C19 are not related to drug-induced idiosyncratic liver injury (DILI)

BACKGROUND AND PURPOSE: The general view on the pathogenesis of drug-induced idiosyncratic liver injury (DILI) is that parent compounds are rendered hepatotoxic by metabolism, mainly by cytochrome (CYP) 450, although other metabolic pathways can contribute. Anecdotal reports suggest a role of CYP 450 polymorphisms in DILI. We aimed to assess in a series of Spanish DILI patients the prevalence of important allelic variants of CYP2C9 and CYP2C19, known to be involved in the metabolism of several hepatotoxic drugs. EXPERIMENTAL APPROACH: Genotyping of CYP2C9 ((*)2, (*)3) and CYP2C19 ((*)2 and (*)3), was carried out in a total of 28 and 32 patients with a well established diagnosis of DILI. CYP2C9 and CYP2C19 variants were analysed in genomic DNA by means of PCR-FRET and compared with previous findings in other Caucasian populations. KEY RESULTS: CYP2C9 and CYP2C19 allele and genotype frequencies were in agreement with Hardy-Weinberg equilibrium. Fourteen patients (50%) were heterozygous and 1(4%) found to be compound heterozygous for the CYP2C9 allele. Seven (22%) were found to carry one and 1(3%) carried two CYP2C19 mutated alleles. No patients were homozygous for (*)3 allele. The distribution of both CYP2C9 and CYP2C19 allelic variants in DILI patients were similar to those in other Caucasian populations. Patients with variant and those with wild-type alleles did not differ in regard to clinical presentation of DILI, type of injury and outcome. CONCLUSIONS AND IMPLICATIONS: We find no evidence to support CYP2C9 and CYP2C19 genetic polymorphisms as predictable potential risk factors for DILI.     

中药“维脑路通”的组成分析研究

以高效液相色谱进行分离,配以薄层层析,紫外光谱等方法研究测定了中药“维脑路通”的组成。定性结果表明“维脑路通”的主要成分有7-羟乙基芦丁、4',7-二羟乙基芦丁、3',4',7-三羟乙基芦丁,3',4',5,7-四羟乙基芦丁等八种主要组分,用色谱法对各组分的含量作了测定。     

Polymorphism of CYP2D6, CYP2C19, CYP2C9 and CYP2C8 in the Faroese population

Objective The purpose of the study was to study the distribution of poor and extensive metabolizers of CYP2C19 and CYP2D6 and to genotype for CYP2C8 and CYP2C9 among 312 randomly selected Faroese.Methods and results The participants were phenotyped for CYP2D6 with the use of sparteine. The distribution of the sparteine metabolic ratio (sparteine/didehydrosparteines) was bimodal, and 14.5% (n=44; 95% CI: 10.7–18.9%) of the subjects were phenotyped as poor metabolizers. The frequency of poor metabolizers was higher (P=0.0002; ² test) among the Faroese than in other European populations (7.4%). Genotype analyses for the CYP2D6*3, *4, *6 and *9 alleles were performed using real-time polymerase chain reaction (PCR) (TaqMan, Foster City, CA, USA), and we found 14.6% (n = 45) (95% CI: 10.8–19.0%) with deficient CYP2D6 genes (*3/*4, *4/*4, *4/*6, *6/*6) in the Faroese population. The subjects were phenotyped for CYP2C19 with the use of mephenytoin and 10 subjects, i.e., 3.2% (95% CI: 1.6–5.9%) were phenotyped as poor metabolizers. Genotype analysis for the CYP2C19*2 and *3 alleles was performed by means of PCR analysis, and 2.9% (n=9) (95% CI: 1.3–5.4%) of the Faroese were found to have a deficient CYP2C19 gene all explained by the CYP2C19*2/*2 genotype. The allele frequencies of the CYP2C9*2 and CYP2C9*3 alleles were 8.8% (95% CI: 6.7–11.4%) and 5.3% (95% CI: 3.7–7.4%), respectively, while the CYP2C8*3 allele frequency was 6.9% (95% CI: 5.0–9.2%). Real-time PCR (TaqMan) was used for both CYP2C9 and CYP2C8 genotype analyses.Conclusion The frequency of CYP2D6 poor metabolizers is twofold higher among the Faroese population than other Caucasians, while the frequencies of Faroese subjects with decreased CYP2C19, CYP2C8 and CYP2C9 enzyme activity are the same as seen in other Caucasian populations. A possible consequence might be a higher incidence of side effects among Faroese patients taking pharmaceuticals that are CYP2D6 substrates.