CYP2C19基因多态性与首发缺血性卒中氯吡格雷二级预防复发风险的关联研究

目的探讨CYP2C19基因多态性与规律服用氯吡格雷预防缺血性卒中二级复发风险之间的关系。方法入组首次缺血性卒中的326例汉族患者,采用DNA微阵列芯片法检测CYP2C19基因多态性,随访患者缺血性卒中复发情况,分析规律服用氯吡格雷的患者卒中复发与CYP2C19基因多态性的关系。结果对入组患者经过1～37个月[平均(14.44±5.07)个月]的随访,共139例规律服用氯吡格雷,其中29(20.86%)例出现卒中复发。中代谢型和慢代谢型患者的复发风险较快代谢型升高,比值比(odds ratio,OR)分别为3.05[95%可信区间(confidence interval,CI)1.11～8.43,P=0.025]和9.17([95%CI2.39～35.16,P0.001]。携带*2(G681A)A等位基因患者的卒中复发风险是携带G等位基因患者的2.63倍(P0.001)。携带*2突变杂合子和纯合子患者卒中复发风险分别是野生型的2.82倍(P=0.026)和9.69倍(P0.001)。携带有1个失功能(loss of function,LOF)等位基因者卒中复发的风险是未携带者的3.02倍,(95%CI 1.13～8.05,P=0.030),携带2个LOF等位基因者卒中复发的风险是未携带者的11.01倍(95%CI 2.67～45.24,P0.001)。多因素Logistic回归分析提示携带LOF等位基因是卒中复发的独立危险因素。结论规律服用氯吡格雷进行二级预防的首发缺血性卒中患者,中慢代谢型患者的卒中复发风险较快代谢型升高,携带CYP2C19 LOF等位基因是首发缺血性卒中患者卒中复发的独立危险因素。     

Impact of CYP2C19 Polymorphism and Proton Pump Inhibitors on Platelet Reactivity to Clopidogrel and Clinical Outcomes Following Stent Implantation

Background

The response to clopidogrel, and some kind of the drug interaction are multifactorial.

Methods and Results

We enrolled 174 consecutive patients and determined CYP2C19 genotypes, measured platelet aggregation, and assessed the relationship between CYP2C19 genotype and platelet reactivity 24 hours after clopidogrel administration, and the risk of cardiovascular events over 18 months follow-up. A sub analysis examined the impact of rabeprazole, a proton pump inhibitor (PPI) less affected by CYP2C19.The CYP2C19 genotype was extensive metabolizer (EM) in 36%, intermediate metabolizer (IM) in 45%, and poor metabolizer (PM) in 19%. Platelet reactivity was significantly lower in the EM group than in the IM and PM groups (EM, IM, PM: 3560 ± 1404, 4203 ± 1302, 5084 ± 1007 AU•min, P < 0.05). The cardiovascular event rate was higher in the IM and PM groups than in the EM group (12.7% and 12.5% vs 1.6%; Hazard ratio for IM 10.6, P = 0.029; for PM 11.3, P = 0.040). No differences were seen between patients taking (N = 50) and not taking (N = 124) rabeprazole in residual platelet aggregation (4407 ± 1360 vs 4048 ± 1394, AU•min, P = 0.2782), or in cardiovascular events (10.0% vs 8.1%, HR 0.97, P = 0.97).

Conclusions

CYP2C19 genotype is associated with an increased risk of cardiovascular events following stent implantation in Japanese patients.     

VASP phosphorylation and genetic polymorphism for clopidogrel resistance in Chinese patients with non-cardioembolic ischemic stroke

Background

Clopidogrel resistance(CR)is found in non-cardioembolic ischemic stroke (NCIS) patients. However, it is still largely unknown how to identify CR in NCIS patients by laboratory and genetic characteristics.

Methods

A total of 95 patients with acute NCIS were recruited. Phosphorylation of the vasodilator stimulated phosphoprotein (VASP) was detected using flow cytometry, and genes(CYP2C19,CYP3A4) were detected using the Sanger method. The baseline of platelet reactivity index (BPRI) before clopidogrel treatment and the platelet reactivity index with clopidogrel treatment (CPRI) for 7 days were measured. Laboratory clopidogrel resistance (LCR) was defined as CPRI of ≥ 50%.Clinical clopidogrel resistance (CCR) was defined as the presence of progressive stroke during hospitalization, stroke recurrence or occurrence of other ischemic vascular events within 6 months.

Results

The incidence of LCR was 41.05% and 18.95% developed CCR. The incidence of LCR was significantly higher in GA/AA patients with CYP2C19 (681G > A) (χ2 = 11.16, P = 0.001) and CYP2C19 (636G > A) (χ2 = 4.829, P = 0.028) than in wildtype GG patients. CYP2C19 (681G > A) (OR 6.272, 95%CI 2.162,18.199,P = 0.001) and CYP2C19 (636G > A) (OR: 5.625,95%CI 1.439, 21.583,P = 0.013) were risk factors for LCR. patients with LCR were more likely to develop CCR (χ2 = 6.021, P = 0.014). The probability of CCR was markedly increased in GA/AA patients with CYP2C19 (681G > A) (χ2 = 10.341, P = 0.001). We identified CYP2C19 (681G > A) (OR 7.814, 95%CI 1.816, 33.618 P = 0.006), Essen score (OR 8.351, 95%CI 1.848, 37.745 P = 0.006), and LCR (OR 5.881, 95%CI 1.373, 25.192, P = 0.017) as risk factors for CCR.

Conclusion

In clinical practice,LCR and CYP2C19 gene polymorphism should be assessed in NCIS patients receiving clopidogrel treatment.The Chinese Clinical Trial Registry number: ChiCTR-ONC-13003406     

Clopidogrel response in ischemic stroke patients: Is polymorphism or gender more important? Results of the CRISP study

Clopidogrel (CLP) is a second generation thienopyridine drug commonly used in secondary prevention of ischemic stroke (IS). Its antiplatelet response maybe variable due to genetic and non-genetic factors. Adipokines may affect platelet aggregation through ADP mediated platelet signalling. However, the combined effect of CYP genetic variants and adipokines on antiplatelet response of clopidogrel is unclear. Patients of IS/Transient ischemic attack (TIAs) within 3 months were prospectively screened following clopidogrel treatment. Major exclusions were cardioembolic and non atherosclerotic strokes. Antiplatelet effect of clopidogrel along with adipokine (Leptin and adiponectin) levels and genotyping of CYP, P2Y12 gene were investigated. Rare genetic variants were confirmed by DNA sequencing. 204 patients with ischemic stroke/TIAs were screened and 163 were recruited. 85 (52.1%) patients were poor responders to clopidogrel. Antiplatelet response to clopidogrel was weaker in females [Median 8.0 (IQR: 3.0–14.0)] compared to males [Median 5.0 (IQR: 2.0–10.0)]. In female subgroup analysis, association was found among high leptin levels and PPI (+) usage in poor responders. None of the genetic variants (CYP2C19*2,*3,*4*, CYP2C9*3, CYP2B6 and P2Y12) were found to influence the antiplatelet effects (p > 0.05). On multivariable logistic regression, a poor clopidogrel response was associated with female gender (Adjusted OR 2.55, 95% CI: 1.05–6.18) and PPI usage (Adjusted OR 2.42, 95% CI: 1.09–5.34). Despite a high prevalence of clopidogrel resistance in the North Indian stroke patients, female gender rather than genetic polymorphisms of CYP and P2Y12 genes may influence its antiplatelet effect. Further research may ascertain the role of gender on clopidogrel response.     

氯吡格雷对不同CYP2C19基因分型脑梗死患者的影响

目的观察氯吡格雷对不同CYP2C19基因分型脑梗死患者血小板CD62P、PAC-1表达和NIHSS评分的影响。方法 56例脑梗死患者根据CYP2C19基因分型分成3组,经氯吡格雷治疗14d,比较3组患者治疗前,治疗后7d、14d的血小板CD62P、PAC-1表达和NIHSS评分的改变。结果 3组患者治疗前血小板CD62P、PAC-1表达和NIHSS评分比较无统计学差异;治疗7d后EM组,IM组的CD62P、PAC-1和NIHSS评分均显著低于治疗前(P0.05),PM组CD62P、PAC-1和NIHSS评分均低于治疗前,但差异无统计学意义(P0.05);治疗14d后,EM组和IM组的CD62P、PAC-1和NIHSS评分均显著低于治疗前(P0.05),也低于治疗后7d(P0.05),PM组的CD62P、PAC-1和NIHSS评分低于治疗前(P0.05),也低于后7d,但差异无统计学意义(P0.05);用药第7天和用药第14天PM组的CD62P、PAC-1表达水平和NIHSS评分均高于EM组(P0.05)。结论脑梗死患者CYP2C19基因形态可能是影响氯吡格雷临床预后的重要影响因素。     

CYP metabolic pathway related gene polymorphism increases the risk of embolic and atherothrombotic stroke and vulnerable carotid plaque in southeast China

ObjectiveTo investigate the association of CYP metabolic pathway-related genetic polymorphisms with the susceptibility to ischemic stroke and stability of carotid plaque in southeast China.MethodsWe consecutively enrolled 294 acute ischemic stroke patients with carotid plaque and 282 controls from Wenling First People's Hospital. The patients were divided into the carotid vulnerable plaque group and stable plaque group according to the results of carotid B-mode ultrasonography. Polymorphisms of CYP3A5 (G6986A, rs776746), CYP2C9*2 (C430T, rs1799853), CYP2C9*3 (A1075C, rs1057910), and EPHX2 (G860A, rs751141) were determined using polymerase chain reaction and mass spectrometry analysis.ResultsEPHX2 GG may reduce the susceptibility to ischemic stroke (OR = 0.520, 95% CI: 0.288 ∼ 0.940, P = 0.030) and AA+AG may increase the risk for ischemic stroke (OR = 1.748, 95% CI: 1.001 ∼ 3.052, P = 0.050). The distribution of CYP3A5 genotypes showed significant differences between the vulnerable plaque and stable plaque groups (P = 0.026). Multivariate logistic regression analysis found that CYP3A5 GG could reduce the risk of vulnerable plaques (OR = 0.405, 95% CI: 0.178 ∼ 0.920, P = 0.031).ConclusionEPHX2 G860A polymorphism may reduce the stroke susceptibility, while other SNPs of CYP genes are not associated with ischemic stroke in southeast China. Furthermore CYP3A5 polymorphism was related with carotid plaque instability.     

Factors related to unfavorable outcome in minor ischemic stroke

BackgroundStroke recurrence and disability are important challenges to overcome in patients with minor ischemic stroke. The aim of our study was to determine the factors associated with unfavorable outcomes in patients with minor ischemic stroke.MethodsThis was a prospective cohort study including patients with minor ischemic stroke with a National Institutes of Health Stroke Scale (NIHSS) score ≤ 4 who were treated at the Bach Mai Hospital stroke center from June 15, 2021, to September 15, 2022. Unfavorable outcome was defined as mRS 2-6 at 90 days. Multivariable logistic regression analysis was conducted to assess risk factors related to clinical outcomes.ResultsOf 678 patients presenting with minor ischemic stroke, there were 90 (13.3%, 90/678) patients with no intracranial artery imaging. Hence, 588 were patients analyzed, of whom 6.0% received thrombolytic therapy, 8.5% developed NIHSS > 4 in 24 hours, and 30.4% had intracranial stenosis > 50%. Compared with the group of unfavorable outcomes, the favorable outcome group had more NIHSS 0-1 (29.9% vs.8.7%, P<0.001), lower cardioembolic (3.2% vs.7.9%, P=0.021), low IV-tPA ratio (4.8% vs.10.3%, P=0.019), lower NIHSS progression > 4 in the first 24 hours (3.9% vs.25.4%, P<0.001), and lower ICAS rate (28.1% vs.38.9%, P=0.02). Multivariable regression analysis of factors affecting unfavorable outcomes included baseline NIHSS 2-4 (OR, 3.85; 95% CI, 1.97-7.52), NIHSS progression > 4 (OR, 7.57; 95% CI, 3.80-15.10), and ICAS (OR 1.68; 95%CI, 1.07-2.64).ConclusionsIn patients with minor ischemic stroke, unfavorable outcomes were associated with baseline NIHSS 2-4, NIHSS progression > 4 points in 24 hours, and ICAS. These factors may identify a patient population in need of close monitoring and at higher risk of adverse outcomes.     

Association of CYP3A4*1G and CYP3A5*3 With the 1-year Outcome of Acute Ischemic Stroke in the Han Chinese Population

Background and purpose: Previous studies have shown that common variants within CYP3A4 and CYP3A5 are associated with statin pharmacokinetics and the risk of cardiovascular disease. However, the association of variants in CYP3A4 and CYP3A5 with the prognosis of ischemic stroke remains undetermined. Therefore, we investigated this herein. Methods: Four hundred thirty-three consecutive patients with acute ischemic stroke were recruited. The outcome at the 1-year follow-up was assessed using the modified Rankin Scale (mRS). Two variants, CYP3A4*1G and CYP3A5*3, were genotyped by the improved Multiple Ligase Detection Reaction platform. Results: Binary logistic regression analysis showed that the CYP3A4*1G/*1G homozygote was associated with poor outcome at 1 year (mRS score ≥2) after adjustment for conventional factors in the additive model (odds ratio [OR] = 2.92; 95% confidence interval, 1.07-7.98; P = .037) and recessive model (OR = 3.37; 95% confidence interval, 1.26-9.04; P = .016). Subgroup analysis indicated that the CYP3A4*1G/*1G homozygote was associated with poor prognosis at 1 year among patients with stable high-intensity atorvastatin therapy (40-80 mg/d) after adjustment for conventional factors in the additive model (OR = 8.16; 95% confidence interval, 1.50-44.44; P = .015) and recessive model (OR = 9.06; 95% confidence interval, 1.72-47.64; P = .009). No significant association was identified between CYP3A5*3 and the 1-year outcome of patients with ischemic stroke. Conclusions: Our study findings suggest that the CYP3A4*1G/CYP3A4*1G genotype may be associated with poor prognosis at 1 year after acute ischemic stroke in the Han Chinese population.     

Effect of tolterodine on sleep structure modulated by CYP2D6 genotype

OBJECTIVE: Tolterodine, a drug for the treatment of overactive bladder symptoms, has a limited entry into the brain, which makes cognitive side effects seldom. However, some case reports have described central-nervous side effects such as sleepiness. The aim of this retrospective analysis was to investigate whether tolterodine-related effects on sleep stage parameters could be explained by different CYP2D6 metabolizer characteristics of subjects. METHODS: Data were taken from two randomized, double-blind, placebo-controlled studies conducted in a cross-over design. Forty-eight volunteers underwent 4 two-night attended polysomnographic studies. Subjective quality of sleep and cognitive function were assessed. A single dose of 4 mg tolterodine or placebo was administered before sleep. Forty-four volunteers gave informed consent for genotyping. We found 19 extensive metabolizers (EM), 20 intermediate metabolizers (IM), 4 poor metabolizers (PM) and 1 ultrarapid metabolizer. There were no significant differences between the groups regarding demographic data. RESULTS: Rapid eye movement (REM) sleep duration as a percentage of total sleep time showed significant reduction (p=0.019) in the group carrying one or more deficient alleles (IM+PM). No significant difference was found with two active alleles of CYP2D6 in the EM group. REM latencies under tolterodine displayed a tendency towards prolongation, which was irrespective of the metabolizer status. Subjective sleep parameters did not show statistically significant changes after tolterodine. Cognitive skills were not affected. CONCLUSION: Our retrospective analysis reveals that a decrease of REM sleep under tolterodine is found only in individuals carrying one or two deficient CYP2D6 alleles.     

Influence of cytochrome 2C19 allelic variants on on-treatment platelet reactivity evaluated by five different platelet function tests

Background

The antiplatelet effect of clopidogrel has been linked to cytochrome P450 2C19 (CYP2C19) carrier status. The presence of loss of function and gain of function variants were found to have a gene-dose effect on clopidogrel metabolism. However, genotyping is only one aspect of predicting response to clopidogrel and several platelet function tests are available to measure platelet response.Patients and methodsWe studied the influence of CYP2C19 allelic variants on on-treatment platelet reactivity as assessed by light transmission aggregometry (LTA), the VerifyNow P2Y12 assay, the VASP assay, multiple electrode aggregometry (MEA), and the Impact-R in 288 patients after stenting for cardiovascular disease. Allelic variants of CYP2C19 were determined with the Infiniti® CYP450 2C19 + assay and categorized into four metabolizer states (ultrarapid, extensive, intermediate, poor).

Results

Platelet reactivity increased linearly from ultrarapid to poor metabolizers using the VerifyNow P2Y12 assay (P = 0.04), the VASP assay (P = 0.02) and the Impact-R (P = 0.04). The proportion of patients with high on-treatment residual platelet reactivity (HRPR) identified by LTA, the VerifyNow P2Y12 assay and the VASP assay increased when the metabolizer status decreased, while no such relationship could be identified for results of MEA and Impact-R. The presence of loss of function variants (*2/*2, *2-8*/wt, *2/*17) was an independent predictor of HRPR in LTA and the VASP assay while it did not reach statistical significance in the VerifyNow P2Y12 assay, MEA, and the Impact-R.

Conclusion

Depending on the type of platelet function test differences in the association of on-treatment platelet reactivity with CYP2C19 carrier status are observed.     

Biological effect of increased maintenance dose of clopidogrel in cardiovascular outpatients and influence of the cytochrome P450 2C19*2 allele on clopidogrel responsiveness

INTRODUCTION: The first aim of this study is to evaluate the biological effect of doubling the maintenance dose of clopidogrel in pre-defined clopidogrel "low responders", compared to the biological effect of the standard dose in "responders". The second aim is to test the influence of the CYP 2C19*2 allele on clopidogrel responsiveness. MATERIALS AND METHODS: The platelet reactivity index (PRI), based on the phosphorylation status of the vasodilatator phosphoprotein, was determined in 81 consecutive cardiovascular outpatients who had been taking clopidogrel 75 mg/day for at least 15 days (visit 1). Patients with PRI>or=50% ("low responders") were then given clopidogrel 150 mg/day. All the patients were again evaluated 15 days later (visit 2) and were genotyped for the CYP 2C19*2 allele. RESULTS: At visit 1, PRI values ranged from 12.6% to 80.4%. In "low responders" (n=45), the mean PRI fell from 62.0+/-6.7% to 49.4+/-11.3% (P<0.001) after 15 days of clopidogrel 150 mg/day, while no significant change was observed in the other patients ("responders"), who remained on the standard dose (mean PRI: 37.7+/-10.4% and 39.9+/-10.8%, P=0.22, in visit 1 and 2, respectively). The CYP 2C19*2 allele was not associated with clopidogrel responsiveness. CONCLUSIONS: Increasing the maintenance dose of clopidogrel from 75 to 150 mg/day for 15 days in "low responders" is associated with a relative 20%-increase in its biological effect, independently of the CYP2C19 genotype, but without reaching the levels observed in "responders". The CYP 2C19*2 allele is not associated with clopidogrel responsiveness in our population of cardiovascular outpatients.     

The cytochrome 2C19*2 and *3 alleles attenuate response to clopidogrel similarly in East Asian patients undergoing elective percutaneous coronary intervention

Introduction

Carriage of CYP2C19*2 allele is associated with diminished platelet response to clopidogrel. However, the loss-of-function impact of CYP2C19*3 allele on antiplatelet effect of clopidogrel has not been definitely verified. We conducted this study to compare decreased response to clopidogrel according to carriage of CYP2C19*2 vs. *3 allele.

Materials and methods

The study included 190 consecutive Korean patients undergoing elective percutaneous coronary intervention. Light transmittance aggregometry and the VerifyNow P2Y₁₂ assay were used to assess platelet reactivity (PR) at least 12 hours after 300-mg loading of clopidogrel. The cutoff of high on-treatment PR (HPR) was defined as 5 μmol/L ADP-induced PR > 50%. CYP2C19 genotype was analyzed by the SNaPshot method.

Results

Carriers of at least one CYP2C19 variant allele were 115 patients (60.5%), and allelic frequency of CYP2C19*2 and *3 was 30.3% and 6.8%, respectively. PR and the rate of HPR increased proportionally according to the number of CYP2C19 variant allele. Carriage of CYP2C19 variant allele was an only independent predictor of HPR in multivariate analysis. When we compare the effect of allelic carriage, there were no significant differences in platelet measures and the rate of HPR between carriers of CYP2C19*2 and/or *3 allele(s) whether they were intermediate or poor metabolizers.

Conclusion

Carriage of CYP2C19*3 allele is associated with diminished antiplatelet effect of clopidogrel, which may be as potent as the loss-of-function effect of CYP2C19*2 allele.     

Genetic determinants of high on-treatment platelet reactivity in clopidogrel treated Chinese patients

Introduction

Cytochrome P450 (CYP), ATP-binding cassette transporters (ABCB1), and paraoxonase-1 (PON1) play crucial roles in clopidogel absorption and bioactivation. Genetic polymorphisms in these genes have been associated with the variability of the response to clopidogrel, however their contribution to high on-treatment platelet reactivity (HPR) in clopidogrel treated Chinese patients is less known.

Materials and methods

Five-hundred Chinese-Han patients treated with clopidogrel for acute coronary syndrome (ACS) were consecutively recruited from the Department of Geriatric Cardiology, General Hospital of Chinese People’s Liberation Army, from September 2010 to September 2012. We assessed the relations of CYP2C19*2 (rs4244285), CYP2C19*3 (rs4986893), CYP2C19*17 (rs12248560), PON1Q129R (rs662) and ABCB1C3435T (rs1045642) to the platelet aggregation after 5 days maintenance dose of clopidogrel administration, and the risk for HPR. The cutoff of HPR was defined as 20 μmol/L adenosine diphosphate (ADP)-induced platelet aggregation > 50%.

Results

Both CYP2C19*2 and *3 alleles were significantly associated with higher platelet aggregation after 5 days maintenance dose of clopidogrel administration (P < 0.00001and P = 0.042, respectively). The platelet aggregation in carriers of at least one CYP2C19 loss-of-function allele (*2 or *3, accounted for 58% of the study population) was obviously higher than that in non-carriers (P < 0.00001). Patients with the CYP2C19*2 allele had a higher risk of HPR than those with the CYP2C19 wild-type genotype [adjusted hazard ratio (HR), 1.56; 95% confidence interval(CI), 1.04–2.33, P = 0.03]. The carriers of at least one CYP2C19 loss-of-function allele could also predict significantly greater risk of HPR compared with non-carriers (adjusted HR1.79,95% CI: 1.33–2.4,P = 0.003). However, the carriage of CYP2C19*3 alone could not predict the risk of HPR significantly (adjusted HR, 1.5; 95% CI: 0.83–3, P = 0.16). Significant relation of CYP2C19*17, PON1Q129R and ABCB1C3435T to the platelet aggregation was not found.

Conclusion

In clopidogrel treated Chinese patients with ACS, carriers of at least one CYP2C19 loss-of-function allele could predict greater risk of HPR, with the impact mainly attributing to CYP2C19*2. Neither ABCB1 nor PON1 genotype could influence the antiplatelet response of clopidogrel in the cohort of Chinese patients.     

A Quantitative Assessment of the Association Between 1425G/A Polymorphism in PRKCH and Risk of Stroke

Previous studies suggested an association between 1425G/A polymorphism in PRKCH and stroke risk, but the results were inconsistent. To obtain a more precise estimation, we carried out a meta-analysis to analyze the effect of 1425G/A SNP in PRKCH on stroke risk. We searched PubMed, ISI Web of Science, Chinese Biomedical Database, China National Knowledge Infrastructure and WANFANG Data for all eligible case–control studies through April 2014. The odds ratios (ORs), together with the 95 % confidence intervals (CIs), were calculated to evaluate the strength of association between 1425G/A SNP and stroke risk. Overall, seven eligible studies involving a total of 4,574 cases and 5,471 controls were included in our meta-analysis. The results showed that the variant genotypes of 1425G/A polymorphism in PRKCH were significantly associated with a higher risk of stroke in all genetic models (GA vs. GG: OR 1.35, 95 % CI 1.24–1.47, P < 0.001; AA vs. GG: OR 1.50, 95 % CI 1.24–1.82, P < 0.001; GA/AA vs. GG: OR 1.37, 95 % CI 1.26–1.49, P < 0.001; AA vs. GA/GG: OR 1.35, 95 % CI 1.12–1.62, P = 0.002; A vs. G: OR 1.29, 95 % CI 1.21–1.39, P < 0.001). In the subgroup analysis, significantly increased risks were also observed for ischemic stroke, larger sample size (>1,000) and population-based studies. The result of our meta-analysis indicated that the 1425G/A SNP in PRKCH may contribute to susceptibility of stroke, especially for ischemic stroke.     

Association of A313 G polymorphism (GSTP1*B) in the glutathione-S-transferase P1 gene with sporadic Parkinson's disease

Genetic predisposition, environmental toxins and aging contribute to Parkinson's disease (PD) multifactorial etiology. Weak environmental neurotoxic factors may accumulate over time increasing the disease risk in genetically predisposed subjects. Polymorphic genes encoding drug-metabolizing-enzymes (DMEs) are considered to account for PD susceptibility by determining individual toxic response variability. In this work, the allelic distributions and genotype associations of three major brain-expressed DMEs were characterized, in sporadic PD cases and controls. No significant association was found between CYP2D6 genotype and PD, but subjects with extensive metabolizer (EM) CYP2D6 phenotype, and the variant GSTP1 *B genotype were at significantly higher PD risk than the corresponding poor or intermediary metabolizers ( CYP2D6 poor metabolizer phenotype+intermediary metabolizers). A significant association was observed between the GSTP1*B allele and zygosity with PD ( GSTP1*A/*B – 51.58%/34.37%, odds ratio (OR) = 2.29; 95% confidence interval (95% CI) = 1.25–4.18; * B /* B – 6.32%/1.05%, OR = 10.67; 95% CI = 1.19–94.79). This association was particularly strong in the elder patients group (≥69 year) who showed double PD risk for GSTP1*B heterozygous, whilst GSTP1*B/*B homozygous were exclusively found amongst patients. An interaction between GSTM1 and GSTP1 was observed in this late onset PD group. The present results suggest that native GSTP1 encoding the fully active transferase variant should play a relevant role in dopaminergic neuroprotection.     

CYP2C19基因型与复发性脑梗死患者氯吡格雷抵抗的关系研究

目的通过CYP2C19基因检测及血小板聚集率综合评估氯吡格雷抵抗,指导复发性脑梗死患者合理用药。方法对2018年1-10月就诊于嘉兴市第二医院神经内科,诊断为复发性脑梗死的患者进行CYP2C19基因测序,分别收集氯吡格雷快代谢、中代谢、慢代谢基因型患者各30例,比较3组患者年龄、性别、BMI、吸烟、高血压、糖尿病及高脂血症等一般临床资料。3组均给予常规剂量氯吡格雷75 mg/d治疗,检测患者使用氯吡格雷前及使用7 d后的血小板聚集率。根据血小板聚集抑制率判断氯吡格雷抵抗情况,分析CYP2C19基因型与患者氯吡格雷抵抗的关系。筛选出氯吡格雷抵抗者(血小板聚集抑制率10%)分至氯吡格雷抵抗组,改用西洛他唑100 mg 2次/日,氯吡格雷半反应(10%≤血小板聚集抑制率30%)及氯吡格雷敏感(血小板聚集抑制率≥30%)者分至非氯吡格雷抵抗组,继续氯吡格雷75 mg/d治疗。3个月后再次检测血小板聚集率,比较不同药物的血小板聚集抑制情况,并观察终点事件发生情况(主要终点:再发脑梗死;次要终点:脑出血和死亡)。结果最终入组患者90例,其中男性49例(54.4%),年龄40～89岁,平均年龄68.27±10.14岁。快、中、慢代谢3组糖尿病(P=0.036)和氯吡格雷抵抗发生率(P0.001)差异均有统计学意义,其中慢代谢组合并糖尿病比率高于中代谢组(P=0.010),慢代谢组氯吡格雷抵抗发生率高于快代谢组(P0.001)及中代谢组(P=0.006)。氯吡格雷抵抗组患者22例(24.4%),非氯吡格雷抵抗组患者68例(75.6%)。Logistic回归分析提示,吸烟(OR 7.792,95%CI 1.899～31.968,P=0.004)、糖尿病(OR 4.466,95%CI 1.122～17.778,P=0.034)及CYP2C19基因慢代谢(OR 13.713,95%CI 2.352～79.959,P=0.004)是复发性脑梗死患者氯吡格雷抵抗的独立危险因素。非氯吡格雷抵抗组(49.51%±4.33%vs 63.73%±7.84%,P0.001)和氯吡格雷抵抗组(55.42%±6.63%vs 76.95%±7.42%,P0.001)患者3个月后的血小板平均聚集率较7 d时均下降,差异有统计学意义。3个月后较非氯吡格雷抵抗组,氯吡格雷抵抗组血小板聚集抑制率更高(21.53%±4.30%vs 14.23%±6.90%,P0.001)。入组患者随访3个月均无终点事件发生。结论吸烟、合并糖尿病及CYP2C19慢代谢基因型是复发性脑梗死患者氯吡格雷抵抗的独立危险因素。西洛他唑能有效抑制血小板聚集,可以作为氯吡格雷抵抗的复发性脑梗死患者的替代性用药。     

Impact of the proton pump inhibitors and CYP2C19*2 polymorphism on platelet response to clopidogrel as assessed by four platelet function assays

Background

Previous studies suggested a possible negative interference of proton pump inhibitors (PPIs) on clopidogrel’s antiplatelet effect because of the competitive inhibition of the CYP 2C19 isoenzyme. Moreover, carriers of the loss-of-function allele of CYP2C19 polymorphism (CYP2C19*2) display significantly lower responses to clopidogrel. In this study, we investigated the association between CYP2C19*2 genotype, PPI intake and clopidogrel resistance in patients with coronary artery disease (CAD) and their effect on clinical outcome.

Methods

We recruited 95 patients with CAD receiving chronic clopidogrel therapy in combination with aspirin. Platelet reactivity was simultaneously assessed by INNOVANCE PFA-100 P2Y, ADP-induced light transmission aggregometry (LTA), flow-cytometric vasodilator-stimulated phosphoprotein (VASP)-phosphorylation assay and multiple electrode aggregometry (Multiplate). Cardiovascular outcomes were recorded during 1-year follow-up period.

Results

Only platelet reactivity assessed by measuring platelet phosphorylated-VASP demonstrated a significant higher platelet reactivity in carriers of CYP2C19*2 (p = 0.023). The other methods displayed higher - but not statistically significant - platelet reactivity in patients carrying the CYP2C19*2 variant as compared with non-carriers. Patients on PPIs demonstrated almost similar suppression of platelet reactivity in comparison with those not treated with PPIs by all platelet function assays. In logistic regression analysis none of the platelet function assays measurements were related with clinical outcomes. Similarly neither CYP2C19*2 genetic variant nor PPI treatment were associated with adverse clinical events.

Conclusions

PPI co-administration did not influence clopidogrel’s antiplatelet effect on laboratory testing by all platelet function assays used. On the contrary, patients carrying CYP2C19*2 genotype had significantly higher residual platelet reactivity as estimated by VASP-phosphorylation assay.     

CYP2C19*2 and other genetic variants affecting platelet response to clopidogrel in patients undergoing percutaneous coronary intervention

Introduction

Information regarding any possible additional effect of genetic variants other than CYP2C19*2 on platelet reactivity in patients undergoing percutaneous coronary intervention (PCI), while on dual antiplatelet therapy, is sparse.

Materials and Methods

Genotyping for CYP2C19*2, CYP2C19*17, CYP2C9*3, CYP2B6*5, ABCB1 and P2RY12 (c.-217 + 2739 T > C) variants was performed in 146 consecutive PCI patients receiving clopidogrel. Platelet reactivity was assessed by the Verify Now P2Y12 point-of-care assay and high on-treatment platelet reactivity (HTPR) was defined as a Platelet Reactivity Unit (PRU) ≥ 235.

Results

We identified 65(44.5%) patients with HTPR and 38(26%) carriers of at least one CYP2C19*2 allele, which had higher platelet reactivity compared to non-carriers [least square (LS) mean difference 44.5, 95%CI 15.8-77.3, p = 0.003]. In the entire study population, the presence of at least one CYP2C19*2 or P2RY12 allelic variant was independently associated with HTPR (OR = 3.02, 95%CI 1.16-7.86, p = 0.023 and OR = 3.11, 95%CI 1.03-9.39, p = 0.05 respectively). In CYP2C19*2 non-carriers, carriers of at least one CYP2B6*5 allelic variant had higher platelet reactivity compared to the remainders (LS mean difference 35.6, 95%CI 3.7-67.6, p = 0.03) and the presence of at least one CYP2B6*5 or P2RY12 allelic variant was independently associated with HTPR (OR = 3.26, 95%CI 1.08-9.86, p = 0.04 and OR = 4.27, 95%CI 1.11-16.4, p = 0.04 respectively).

Conclusions

Apart from the CYP2C19*2, other genetic variants involved in clopidogrel metabolism and action like CYP2B6*5 and P2RY12 seem to have an important association with HTPR.     

个体化抗血小板治疗对缺血性卒中二级预防的效果研究

目的 研究个体化抗血小板治疗在缺血性卒中二级预防的效果。 方法 选择2013年3月-2014年5月于陕西省人民医院就诊的急性缺血性卒中患者207例,随机分为 常规治疗组与个体化治疗组。常规治疗组应用阿司匹林100 mg/d抗血小板治疗。个体化治疗组应用 Essen卒中风险评分量表（Essen Stroke Risk Score,ESRS）将高危组给予氯吡格雷75 mg/d,低危组给 予阿司匹林100 mg/d抗血小板治疗。7 d后进行血栓弹力图（thromboela stogram,TEG）及CYP2C19基因型 检测,结合TEG及CYP2C19基因型结果,决定抗血小板治疗方案。随访1年,比较个体化治疗组和常规 治疗组患者终点事件发生率。 结果 CYP2C19快代谢基因型、中间代谢基因型患者应用氯吡格雷的血小板抑制率明显高于慢代谢 型,结果差异有显著性（P =0.018,P =0.015）。个体化治疗组（112例）和常规治疗组组（95例）终点事 件发生率差异无显著性（P＞0.01）。 结论 CYP2C19快代谢基因型、中间代谢基因型患者应用氯吡格雷的血小板抑制率明显高于慢代谢 型。与阿司匹林常规治疗方案相比,利用CYP2C19基因多态性与TEG检测指导下的个体化抗血小板方 案未显示降低缺血性卒中后终点事件发生率,可能需要更大规模、随访时间更长的研究。     

Lacunar infarcts: functional and cognitive outcomes at five years in relation to MRI findings

BACKGROUND: There are few long-term follow-up studies of patients with lacunar infarcts (LIs). The purpose of this 5-year follow-up study was to assess functional and cognitive outcome in relation to MRI findings. METHODS: 81 patients with a first-ever LI were followed for 5 years with respect to mortality, stroke recurrence, functional and cognitive outcome. T(2)-weighted MRI was performed at baseline and at 5 years. The presence of basal ganglia lesions and white matter lesions was scored according to the European Task Force rating scale. Functional outcome was assessed with the Oxford Handicap Scale (OHP). Cognition was assessed with the Mini Mental State Examination (MMSE). RESULTS: The 5-year mortality was 19%. Predictors for death were age (OR = 1.07, 95% CI 1.03-1.11), ischemic heart disease (OR = 2.1, 95% CI 1.1-4.1) and impairment score (OR = 1.16, 95% CI 1.02-1.32). 30% of the patients had a recurrent stroke. Predictors for recurrent stroke were diabetes mellitus (OR = 1.7, 95% CI 1.2-7.4) and amount of white matter lesions (OR = 1.7, 95% CI 1.2-2.7). 36% of the patients were functionally dependent (defined as OHP >2). Predictors for functional dependency were impairment score (OR = 1.71, 95% CI 1.12-2.59), MMSE (OR = 0.55, 95% CI 0.33-0.91) and stroke recurrence (OR = 84, 95% CI 9.4-745). 16% of the patients had cognitive impairment (defined as MMSE <24). Stroke recurrence and white matter score, but not basal ganglia score, were correlated to cognitive impairment. CONCLUSIONS: Many LI patients have a good functional outcome at 5 years. For older patients, for patients with an initial severe stroke, and with additional vascular risk factors, however, the prognosis is more severe, with an increased risk for mortality, stroke recurrence, and physical and cognitive decline.