CYP2C19基因型对丙戊酸及其与苯妥英联合用药时血药浓度影响

目的探讨细胞色素P450 2C19(CYP2C19)基因对丙戊酸(VPA)血药浓度,以及VPA和苯妥英(PHT)联合应用时对其VPA血药浓度的影响.方法应用变性高效液相(DHPLC)技术对CYP2C19两个常见的等位基因突变进行了分析;应用荧光偏振免疫法(FPIA)测定口服抗癫痫药物患者的血药浓度.结果81例癫痫患者中CYP2C19外显子4(*3)和外显子5(*2)位点均为野生型(*1/*1)的发生率为37.0%,CYP2C19*2和CYP2C19*3的等位基因频率分别为31.5%和3.7%.单一应用VPA时,弱代谢患者较正常代谢患者的VPA血药浓度有所升高(P＜0.05).联合应用PHT和VPA可使VPA血药浓度显著降低(P＜0.01),CYP2C19正常代谢患者VPA血药浓度降低尤为明显(P＜0.01);在VPA与PHT联合用药过程中,约半数CYP2C19正常代谢患者VPA血药浓度不能达到治疗血药浓度.结论CYP2C19基因多态性影响VPA的血药浓度变化,在联合应用PHT时对VPA血药浓度的影响尤为明显,从而影响抗癫痫的临床疗效.     

CYP2C19基因多态性对AIS患者血管内支架治疗预后的影响

目的 探讨CYP2C19基因多态性对急性缺血性脑卒中(AIS)患者血管内支架治疗预后的影响。方法 选取2019年1月至2022年1月海南医学院第一附属医院收治的AIS患者140例,根据治疗预后分为预后不良组和预后良好组。检测AIS患者CYP2C19基因型,分析CYP2C19基因多态性与AIS患者预后的相关性。结果 140例AIS患者出院后随访6个月后预后不良36例(25.71%),发生心脑血管不良事件20例(14.29%)。CYP2C19基因型包括快代谢型(EM) 66例,中代谢型(IM) 59例,慢代谢型(PM) 15例,CYP2C19功能基因突变74例(52.86%)。预后不良组患者脑梗死体积大于预后良好组,入院NIHSS评分高于预后良好组(P<0.05);预后不良组CYP2C19基因突变率也显著高于预后良好组(P<0.05)。Logistic回归分析显示,脑梗死体积、入院NIHSS评分、CYP2C19基因突变是AIS患者预后不良的独立危险因素(P<0.05)。结论 AIS患者CYP2C19基因多态性与临床预后密切相关,CYP2C19基因突变是导致预后不良的重要因...     

CYP2C19基因多态性与奥氮平所致药物性肝损伤的关联性研究

目的:研究细胞色素酶CYP2C19基因多态性与奥氮平所致药物性肝损伤(DILI)间的关联性。方法:对127例单一服用奥氮平的精神分裂症患者的CYP2C19位点rs4244285、rs4986893、rs12248560进行基因分型检测,分析比较服药后出现药物性肝损伤(DILI)患者(DILI组)与未出现DILI患者(非DILI组)3个SNPs等位基因及基因型频率差异。结果:两组间3个等位基因和基因型频率、各代谢类型频率比较差异无统计学意义(P0.05),在3位点基因类型比较中,DILI组*1/*3基因频率低于非DILI组,差异有统计学意义(P=0.034)。结论:CYP2C19基因多态性与奥氮平所致DILI易感性可能有关,CYP2C19中*1/*3基因型可能是奥氮平所致DILI的保护性因素。     

丙戊酸代谢相关CYP2C19基因多态性在癫痫患儿体内的分布及治疗个体化研究

目的：对癫痫患儿体内CYP2C19的基因多态性进行研究,并进行基因型与患儿体内丙戊酸血药浓度关系的研究,以对患儿进行治疗个体化。方法采用聚合酶链反应－限制性片段长度多态性检测技术对2012‐12—2014‐03来我院及其他医院神经内科654例确诊为癫痫患儿的CYP2C19基因型进行检测,同时对仅服用丙戊酸进行抗癫痫治疗的228例患儿体内的丙戊酸稳态血药浓度进行检测,进而探求CYP2C19的基因型与血药浓度的相关性。结果 CYP2C19具有基因多态性,各基因型分布频率不同,其中*1／*1型为41.9％、*1／*2型为41.1％、*1／*3型为6.4％、*2／*2型为7.4％、*2／*3型为2.9％和*3／*3型为0.3％;同时入选组的228例患儿中快、中、慢代谢型所占的频率分别为40.8％、44.7％和13.5％;同时测得*1／*1型、*1／*2型、*1／*3型、*2／*2型、*2／*3型所对应的稳态血药浓度（m g／L ）分别为45±20、64±16、68±21、73±28、72±18;经统计分析发现,*2／*2型与*1／*1型血药浓度体质量剂量比值存在差异具有统计学意义（ P＜0.05）。结论癫痫患儿体内CYP2C19具有多态性,其分布规律与其他正常人群的分布规律基本一致,患儿服用丙戊酸时,其CYP2C19基因型与体内丙戊酸的血药浓度具有相关性。因此提醒我们,对癫痫患儿应用丙戊酸进行抗癫痫治疗时,可参考CYP2C19基因分型结果,预测血药浓度变化,对患儿进行个体化的治疗。     

回、汉族癫痫患者ABCB1基因C3435T多态性与癫痫耐药的相关性研究

目的 研究ABCB1基因C3435T的单核苷酸多态性在回、汉族癫痫人群中的分布特点;探讨回、汉族癫痫患者人群中ABCB1基因型对癫痫耐药的影响,进一步阐明癫痫耐药机制.方法 收集宁夏地区同族癫痫耐药患者33例,回族药物敏感癫痫患者29例,汉族癫痫耐药患者62例,汉族药物敏感癫痫患者61例,采用聚合酶链反应-限制性片段长度多态性(PCR-RFLP)方法对入选患者的ABCB1基因C3435T位点进行基因分型,并随机抽取11%的基因分型样本进行直接测序证实.统计4组癫痫患者中C3435T的基因型、等位基因频率,分别用x2等检验进行统计分析.结果 回、汉族对照比较,回族癫痫患者中外显子26 C3435T位点基因型及等位基因频率与汉族癫痫患者均没有差异,(均P＞0.05).与药物敏感组比较,耐药组外显子26C3435T-CC基因型明显多于药物敏感组(P＜0.001),而TT基因型则少于药物敏感组(P＜0.001).与药物敏感组比较,耐药组C等位基因频率高于药物敏感组,而T等位基因频率低于药物敏感组(P＜0.001).结论 在中国回、汉族人群中均存在的ABCB1-C3435T位点基因多态性与癫痫耐药有关联,这一位点的基因多态性可以影响癫痫患者对抗癫痫药物(AEDs)的反应性.     

CYP2C19基因多态性对长期服用氯吡格雷脑梗死患者卒中复发的影响

目的探讨长期服用氯吡格雷的初发脑梗死患者卒中复发与CYP2C19基因多态性的关系。方法对78例初发脑梗死后长期(≥1 y)服用氯吡格雷的患者,根据入组时是否脑梗死复发分为复发组与未复发组,通过CYP2C19基因芯片检测系统对两组患者的CYP2C19基因型进行检测。结果 78例中,复发组32例,未复发组46例。两组患者在性别、年龄、吸烟、高血压、糖尿病、血脂等的差异均无统计学意义(均P>0.05);所检的78例共检出三种等位基因:CYP2C19*1、CYP2C19*2、CYP2C19*3,等位基因频率分别是61.54%、33.33%、5.13%。两组患者共检出6种基因型:CYP2C19*1/*1、CYP2C19*1/*2、CYP2C19*1/*3、CYP2C19*2/*2、CYP2C19*2/*3和CYP2C19*3/*3。未复发组CYP2C19*1等位基因和CYP2C19*1/*1基因型频率显著高于复发组,分别为76.1%:40.6%(P<0.01),58.7%:18.8%(P<0.001),而未复发组CYP2C19*2等位基因频率和CYP2C19*2/*2基因型频率显著低于复发组,分别为19.6%:53.1%(P<0.01),4.3%:31.3%(P<0.01),而两组其余等位基因频率和基因型频率差异无统计学意义(均P>0.05)。结论长期服用氯吡格雷的脑梗死患者卒中复发与CYP2C19基因突变有关,对于需长期服用氯吡格雷预防脑梗死复发的患者,进行CYP2C19基因型的检测是必要的。     

河南地区汉族人群丙戊酸钠代谢相关基因CYP2C19的多态性分布调查分析

目的探讨河南地区丙戊酸钠代谢相关基因CYP2C19多态性的相关分布。方法采用聚合酶链反应-限制性片段长度多态性检测技术对我院无亲缘关系的250例患者的基因型进行检测。结果 CYP2C19*1*1频率为46.0%、CYP2C19*1*2频率为38.4%、CYP2C19*1*3频率为6.0%、CYP2C19*2*2频率为6.4%、CYP2C19*2*3频率为2.8%、CYP2C19*3*3频率为0.4%。结论河南地区汉族人群CYP2C19多态性的相关分布与全国其他地区比较无显著性差异,临床医师在使用丙戊酸钠及苯妥英钠等药物进行抗癫治疗时可以参考相关基因检测结果。     

丙戊酸药物浓度与CYP286基因多态性的相关性研究

目的:探讨丙戊酸(VPA)药物浓度与细胞色素P4502B6(CYP2B6)基因多态性的关系。方法:选择符合入选条件的癫患者72例,提取外周血DNA,应用聚合酶链反应和限制性核酸内切酶方法分析患者的CYP2B6基因型及等位基因;应用荧光偏振免疫法测定患者VPA的血药浓度。结果:72例癫患者中CYP2B6基因型为*1/*1为39例(54.2%),*1/*6为29例(40.3%),*6/*6为4例(5.5%),根据基因型将患者分为两组,A组(CYP2B6*1/*1)和B组(CYP2B6*1/*6或CYP2B6*6/*6)。B组患者VPA的标准血药浓度平均值较A组高,且差异有统计学意义(P<0.05)。结论:CYP2B6是VPA的代谢酶,CYP2B6基因多态性可影响VPA的血药浓度,对含有CYP2B6*6等位基因的患者应用VPA时,其血药浓度高,提示对VPA药物代谢有影响。     

缺血性脑血管病患者 CYP2 C19 基因多态性的相关性研究

目的探讨缺血性脑血管病(ischemic cerebrovascular disease,ICVD)患者CYP2C19基因单核苷酸多态性(single nucleotide polymorphism,SNP)与临床特征、治疗效果之间的关系。为脑血管疾病患者服用抗血小板药物的个体化治疗提供参考依据。方法昆明医科大学第一附属医院神经外科2015年1月—2017年4月间完善CYP2C19(*2、*3、*17)基因检测的153例患者作为研究对象。将所有患者分别按每个基因位点基因检测的结果分为突变组及非突变组,分析CYP2C19基因各位点突变与患者临床特征、缺血性脑血管病发病及服药后发生缺血事件的关系。结果本组153例患者中,男70例(45. 8%),女83例(54. 2%),平均年龄(53. 2±11. 6)岁; CYP2C19(*2、*3、*17)各位点基因型突变的频率分别为53. 6%、9. 2%及2. 0%。CYP2C19*2位点突变与非突变组患者的吸烟、饮酒比率及血胆固醇(TC)、低密度脂蛋白胆固醇含量比较,差异均有统计学意义(P 0. 05-0. 01); CYP2C19*3位点突变与非突变组患者的血高密度脂蛋白胆固醇含量的差异有统计学意义(P 0. 005)。CYP2C19 3个位点突变与与非突变组患者发生ICVD的差异均无统计学意义(均P 0. 05)。CYP2C19*2位点突变患者服药后的缺血事件发生率比非突变患者明显增加(P 0. 05)。结论患者是否患有ICVD与CYP2C19(*2、*3、*17)基因位点多态性无明显关系;抗血小板治疗后是否发生缺血性事件与CYP2C19*2基因位点突变有关。因CYP2C19*2基因的突变率较高(本组患者达53. 6%),建议患者服抗血小板药前先行基因检测,以避免可能预后不佳。     

CBZ和CBZE血药浓度个体差异与CYP3A5*3基因多态性的相关性分析

目的 探讨卡马西平(CBZ)药物代谢个体差异性的遗传学机制,从而指导临床抗癫痫治疗中的个体化用药.方法 选取确诊为癫痫并适用CBZ的患者58例.首先利用PCR技术扩增患者外周血中包含等位基因CYP3A5*3(rs776746)的基冈片段;其次采用基因测序法确定该等位基因各基因型的分布,将包含原始碱基(A)的基因序列归为A组,而将只含有突变碱基(C)的基因序列归为B组;最后,应用高效液相色谱法测定两组患者外周血中CBZ及其代谢产物10,11-环氧化卡马西平(CBZE)的血药浓度.采用t检验,比较A、B两组患者CBZ和CBZE血药浓度的差异.结果 A组患者CBZ的浓度明显低于B组(P＜0.01);A组患者CBZE的浓度明显高于B组(P＜0.05).CYP3A5 * 3的基因多态性与CBZ及其代谢产物CBZE的血药浓度相关,CYP3A5*3突变纯合型CBZ代谢减慢,血药浓度相应增高,应给予相对小剂量的CBZ,以提高临床用药的安全性.结论 CYP3A5*3的基因多态性可能作为临床治疗中CBZ剂量个体化的一项重要参考依据.     

Role of CYP2C9 polymorphism in phenytoin-related metabolic abnormalities and subclinical atherosclerosis in young adult epileptic patients

PurposeWe investigated the influence of the CYP2C9 polymorphism on the lipid profile, insulin resistance, and subclinical atherosclerosis in young epileptic patients.MethodsWe performed a cross-sectional study to evaluate the association between CYP2C9 polymorphism and lipid profile, glucose homeostasis, and subclinical atherosclerosis in young epileptic patients via the ankle brachial index.ResultsThe frequencies of CYP2C9*1 (CYP2C9 wild type gene) and CYP2C9*3 (CYP2C9 polymorphism gene) were 75% and 25%, respectively. The mean serum total triglyceride and LDL levels were significantly higher in the wild type gene subjects than in the CYP 2C9 polymorphism gene subjects. Also, the CYP 2C9 polymorphism had marginally significant lower mean serum HDL levels than the wild type gene subjects. No patients with CYP 2C9 polymorphism gene had elevated fasting blood sugar, and insulin resistance was found in only 10 of the 75 subjects. The mean ABI was statistically significantly lower in the wild type subjects than in the CYP2C9 polymorphism gene subjects.ConclusionOur study indicates that young epileptic patients with the CYP2C9 polymorphism gene have a low risk of subclinical atherosclerosis.     

The role of CYP2C9 polymorphisms in phenytoin-related cerebellar atrophy

PurposePhenytoin is known to be able to induce cerebellar atrophy in patients with epilepsy. It is also known that a CYP2C9 mutation (*2 or *3) reduces phenytoin metabolism by 25–50% and can increase the risk of phenytoin-related side effects. We examined the influence of CYP2C9 polymorphisms on total cerebellar volume and cerebellar gray and white matter volumes in patients with epilepsy taking phenytoin.MethodsFor the genotyping, 100 adult patients with documented epilepsy who had been taking phenytoin for >1 year were selected. From this group, we randomly selected 19 mutant individuals (MT group; CYP2C9*2 and *3) for a whole-brain volume measurement using MRI and 19 wild-type individuals (group WT; CYP2C9*1) with similar clinical and demographic characteristics to those in the MT group for comparison. Total intracranial volume measurements were used to normalize the acquired volumes, which were separated into gray matter volume, white matter volume, and total volume.ResultsThe MT group exhibited a significant reduction in cerebellar white matter volume (p = 0.002) but not in total cerebellar volume.ConclusionOur study is the first to report evidence linking CYP2C9 polymorphism and a reduction in cerebellar volume in epileptic users of phenytoin.     

CYP2C19 polymorphism and risk for essential tremor

Many patients with essential tremor (ET) develop acute adverse effects to primidone. We investigated the association between CYP2C19 polymorphism (possibly related to primidone metabolism) and the risk for developing essential ET and acute adverse effects to primidone. Leukocytary DNA from 200 ET patients and 300 healthy controls was studied for the genotype CYP2C19 and the occurrence of CYP2C19 allelic variants by using allele-specific PCR amplification and Sma I and BamH I RFLP analyses. The frequencies of the genotype CYP2C19*1/CYP2C19*2 and of the allelic variant CYP2C19*2 were significantly higher in ET patients than in controls. The mean age at onset of ET did not differ significantly between patients with genotypes CYP2C19*1/CYP2C19*2andCYP2C19*1/CYP2C19*1. The frequencies of the genotype CYP2C19*1/CYP2C19*2 and the allelic variant CYP2C19*2 were similar in ET patients who developed acute adverse effects to primidone, in those who tolerated primidone and in controls; the frequencies were also similar in patients with head, voice, tongue and chin tremor compared with controls. These results suggest that heterozygosis CYP2C19*1/CYP2C19*2 is associated with the risk for ET, but not with the age at onset of ET, the presentation of acute side effects of primidone, or the existence of head, voice, tongue or chin tremor.     

Changes at the CYP2C locus and disruption of CYP2C8/9 linkage disequilibrium in patients with essential tremor

To identify low-penetrance genes related to sporadic essential tremor (ET) at the CYP2Clocus, located in chromosome 10 q23.33. Leukocytary DNA from 200 ET patients and a control group of 300 unrelated healthy individuals with known CYP2C19 genotypes was studied for common CYP2C8 and CYP2C9 allelic variants by using amplification-restriction analyses. Patients with ET showed the following differences compared with healthy subjects: a 1.6-fold reduction in the frequency for CYP2C8*3 (p=0.006), a 1.35-fold reduction of CYP2C9*2 (p=0.05) and a 1.52-fold reduction in the frequency for CYP2C9*3 (p=0.07). The frequency for patients with ET carrying at least one defective allele was 1.33-fold reduced as compared with healthy subjects (p=0.002). In addition, a disruption of the CYP2C8*3/CYP2C9*2 linkage disequilibrium was observed in ET patients, with a 2.1-fold reduction in the percentage for carriers of the haplotype CYP2C8*3 plus CYP2C9*2 in ET patients (p=0.0001). These findings were independent of gender, age, age of onset, or clinical symptoms. These results suggest that alterations at the CYP2C gene locus are associated with the risk for ET.     

The Effects of Genetic Polymorphisms of CYP2C9 and CYP2C 19 on Phenytoin Metabolism in Japanese Adult Patients with Epilepsy: Studies in Stereoselective Hydroxylation and Population Pharmacokinetics

Summary: Purpose : The aim of this study was to clarify the effects of genetic polymorphisms of cytochrome P450 (CYP) 2C9 and 2C19 on the metabolism of phenytoin (PHT). In addition, a population pharmacokinetic analysis was performed.
Methods: The genotype of CYP2C9 (Arg¹⁴⁴/Cys, Ile³⁵⁹/Leu) and CYP2C19 (*1, *2 or *3) in 134 Japanese adult patients with epilepsy treated with PHT were determined, and their serum concentrations of 5-(4-hydroxyphenyl)-5-phenylhydantoin (p-HPPH) enantiomers, being major metabolites of PHT, were measured. A population pharmacokinetic analysis (NONMEM analysis) was performed to evaluate whether genetic polymorphism of CYP2C9/19 affects the clinical use of PHT by using the 336 dose-serum concentration data.
Results: The mean maximal elimination rate (Vmax) was 42% lower in the heterozygote for Leu359 allele in CYP2C9, and the mean Michaelis-Menten constants (K,) in the heterozygous extensive metabolizers and the poor metabolizers of CYP2C19 were 22 and 54%, respectively, higher than those without the mutations in CYP2C9/19 genes. (R)- and (5')- p -HPPHPHT ratios were lower in patients with mutations in CYP2C9 or CYP2C19 gene than those in patients without mutations.
Conclusions: Although the hydroxylation capacity of PHT was impaired with mutations of CYP2C9/19, the impairment was greater for CYP2C9. In view of the clinical use of PHT, two important conclusions were derived from this population study. First, the serum PHT concentration in patients with the Leu359 allele in CYP2C9 would increase dramatically even at lower daily doses. Second, the patients with CYP2C19 mutations should be treated carefully at higher daily doses of PHT.     

Paradoxical urinary phenytoin metabolite (S)/(R) ratios in CYP2C19*1/*2 patients

Phenytoin (PHT) is primarily metabolized to 5-(4'-hydroxyphenyl)-5-phenylhydantoin (p-HPPH), accounting for 67-88% of an administered dose in humans. p-HPPH is formed by the cytochrome (CYP) 450 enzymes CYP2C9 and CYP2C19, then glucuronidated and excreted into the urine. CYP2C9 catalyses the prochiral formation of (R) and (S)-p-HPPH, and is approximately 40 times more stereoselective towards the formation of the (S) isomer whereas CYP2C19 is not stereoselective. Because of differential stereoselectivity, polymorphisms in the genes can alter the (S)/(R)-p-HPPH ratios. Genotyping for CYP2C9 and CYP2C19 was accomplished by a Taqman based assay. Twelve and twenty-four hour urine samples were collected from 45 epilepsy patients taking PHT under steady-state conditions and (S)/(R) ratios of p-HPPH were determined by chiral HPLC separation. The mean urinary (S)/(R) ratio in the 12-24h urine collection in subjects homozygous for CYP2C9*1/*1, CYP2C19*1/*1 was 24.2+/-3.1(n=21), whereas ratios in CYP2C9*1/*2 and CYP2C9*1/*3 subjects, were 11.1+/-3.3(n=7) and 2.7+/-0.6(n=2), respectively. One CYP2C9*2/*3 patient had a ratio of 2.1. Unexpectedly, CYP2C9*1/*1, CYP2C19*1/*2 subjects had a mean (S)/(R) ratio as low as 12.9+/-1.7(n=12). Our results are generally consistent with single dose PHT studies. However, the (S)/(R)-p-HPPH ratios for the CYP2C9*1/*1, CYP2C19*1/*2 subjects, expected to be in the range of 30-40, were only 12.9, suggesting some undetected linkage disequilibrium between CYP2C9 and CYP2C19 genes that could affect PHT elimination. Furthermore, our study suggests that measurement of urine ratios cannot be used as a marker for genotype determination.     

The association between CYP 2C9 polymorphism and bone health

PurposeThere is a strong scientific rationale to support the view that cytochrome P450 (CYP P450) enzyme-inducing AEDs induce bone loss in patients with epilepsy. However, no study has investigated the association between CYP 2C9 polymorphism and bone mineral density (BMD), 25-hydroxyvitamin D or parathyroid hormone levels in patients with epilepsy. This study sought to determine the association between BMD and CYP 2C9 polymorphism.MethodsNinety-three patients taking phenytoin as monotherapy were examined for CYP 2C9 polymorphism, vitamin D level and parathyroid hormone level and underwent basic chemistry testing. The bone mineral density of the lumbar spine and left femur were measured using dual-energy X-ray absorptiometry.ResultsThe results indicated that about 18.3% of the patients with epilepsy were positive for CYP2C9*3. Furthermore, bone mineral density was associated with CYP 2C9 polymorphism epileptic patients. Specifically, patients with 2C9 polymorphism had higher T-scores and Z-scores of the femoral neck (p = 0.02 and 0.04, respectively), but not of the lumbar spine (p = 0.27 and 0.06, respectively). There was also a trend of having higher serum PTH levels and statistically significantly lower 25-hydroxyvitamin D levels in patients with wild type than in those compared with CYP 2C9 polymorphism (p = 0.05 and 0.03, respectively). Additionally, the patients with CYP 2C9 polymorphism had higher plasma levels of phenytoin, particularly when compared with those with wild type (p = 0.01). However, there was no association between serum levels of phenytoin and low BMD at femoral neck or lumbar spine.ConclusionCYP 2C9 polymorphism is associated with higher BMD, independent of plasma levels of phenytoin.     

The influence of cytochrome oxidase CYP2A6, CYP2B6, and CYP2C9 polymorphisms on the plasma concentrations of valproic acid in epileptic patients

Objectives

To investigate influences of the functional polymorphisms of Cytochrome P450 isozymes 2A6 (CYP2A6), 2B6 (CYP2B6), and 2C9 (CYP2C9) on pharmacokinetics of VPA in vivo.

Patients and methods

In the study, we analyzed the genotypes of CYP2A6, CYP2B6, and CYP2C9 and their contribution to the steady-state standardized plasma VPA concentrations in 179 subjects with epilepsy of a Northern Han Chinese population. The genotypes were detected by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP).

Results

The subjects with one or two variant CYP2A6*4 alleles showed higher mean plasma VPA concentrations compared with non-*4 alleles [(3.4 ± 0.4) μg kg ml⁻¹ mg⁻¹ vs. (3.6 ± 0.4) μg kg ml⁻¹ mg⁻¹, p = 0.0055]. A significant difference [one-way ANOVA (p = 0.0203)] was also found between mean plasma VPA concentrations and the CYP2B6 genotypes. In addition, subjects with the heterozygous genotype CYP2C9*3 had higher mean plasma VPA concentrations than did those subjects with the wild-type genotype [(3.9 ± 0.4) μg kg ml⁻¹ mg⁻¹ vs. (3.4 ± 0.4) μg kg ml⁻¹ mg⁻¹, p = 0.0001].

Conclusion

The presently evaluated variant alleles in the CYP2A6, CYP2B6, and CYP2C9 genes may explain part of the substantial variability in VPA pharmacokinetics between different subjects.     

Relationship between CYP2C19*2, *3 gene polymorphism and the recurrence in ischemic stroke patients treated with clopidogrel in China: A meta-analysis

BackgroundThe relationship between CYP2C19 *2,*3 gene variants and the recurrence in ischemic stroke patients treated with clopidogrel is still controversial according to the available published literature. To evaluate correlations between CYP2C19 *2,*3 gene variants, metabolic typing according to *2, *3 SNPs (the polymorphism of rs4244285, rs4986893) and stroke recurrence, we performed this study through meta-analysis.MethodsLiteratures reporting the relationship between CYP2C19*2 and *3 polymorphism and the recurrence in ischemic stroke patients treated with clopidogrel were searched in CNKI, Wanfang Database, VIP, China Biomedical Database, PubMed and Cochrane Library from the establishment database to December 2020. Meta-analysis was performed with RevMan 5.3.ResultsA total of 9 articles with 10 trials involving 1333 ischemic stroke patients were included. The results of meta-analysis showed CYP2C19*2 GA/AA genotype had a higher risk of recurrent stroke than GG in patients with ischemic stroke treated with clopidogrel(P<0.05) (GA+AA vs. GG:OR=2.50, 95% CI:1.66～3.75;GA vs. GG:OR=2.16, 95% CI:1.41～3.31;AA vs. GG:OR=4.40, 95% CI:2.39～8.08; AA vs. GA:OR=2.15, 95% CI:1.20-3.84; allele A vs. G:OR=2.08, 95% CI:1.58-2.75). There was no significant difference in stroke recurrence risk between CYP2C19*3 GA vs. GG genotype (P=0.65)(OR=0.86,95% CI:0.44～1.67). Compared with extensive metabolizer (EM), patients with intermediate metabolizer (IM) and poor metaholizer (PM) of CYP2C19 had a higher risk of stroke recurrent after clopidogrel treatment (IM+PM vs. EM:OR=2.20, 95%CI:1.58～3.08, P<0.05; IM vs. EM:OR=2.06,95% CI: 1.45～2.91, P<0.05;PM vs. EM: OR=3.32,95% CI:1.98～5.56, P<0.05; PM vs. IM: OR=1.45,95% CI: 0.91～2.32,P=0.11).ConclusionAmong ischemic stroke patients taking clopidogrel, CYP2C19*2 gene mutation and CYP2C19 metabolizer were associated with stroke recurrence, CYP2C19*2 and *3 gene carriers were more likely to stroke recurrent than CYP2C19*1 gene carriers.     

Unusual side-effects due to clobazam: a case report with genetic study of CYP2C19

We describe the case of a 10-year-old girl with two epileptic seizures and subcontinuous spike-waves during sleep, who presented unusual side-effects related to clobazam (CLB) monotherapy. High plasma levels of N-desmethyl-clobazam (N-CLB), the major metabolite of CLB were detected. The patient and her parents underwent molecular analysis of the CYP2C19 gene, which may be implicated in the metabolism of this drug. Our patient presents one copy of the most common mutation (CYP2C19*2) affecting the activity of the isoenzyme and probably another rare or private mutation. CLB and N-CLB plasma level dosages and molecular analysis may be useful when a poor metabolic condition is suspected.