MDR1基因多态性对替米沙坦血药浓度和药动力学影响研究

目的:探讨健康志愿者和高血压患者的多药耐药基因(Multidrug resistance 1 gene,MDR1) C3435T基因多态性对替米沙坦血药浓度和药动学的影响.方法:采用聚合酶链反应(Polymerase chain reaction,PCR)和限制性内切片段多态性(Restriction fragment length polymorphism,RFLP)的方法对19名健康志愿者和61例高血压患者进行MDR1基因分型;使用HPLC-MS法测定志愿者单剂量口服40 mg替米沙坦48 h内血药浓度和高血压患者的稳态血药浓度.比较替米沙坦在不同基因型的健康志愿者单剂量药动学及高血压患者稳态血药浓度的差异.结果:在61例高血压患者中,MDRlCC型纯合子频率39.34％,TT型纯合子频率11.48％,CT型杂合子频率49.18％,C3435T发生率在健康人群和高血压患者之间没有明显的差异,C3435T的三个不同基因型志愿者Cmax、tmax、t1/2、AUC0-48、AUC0-∞和CL差异无统计学意义(P＞0.05).三个基因型高血压患者的稳态血药浓度差异无统计学意义(P＞0.05).结论:MDR1C3435T基因多态性对替米沙坦的血药浓度和药动学无影响.     

MDR1基因C3435T多态性对替米沙坦稳态血药浓度及降压疗效的影响

目的：探讨多药耐药基因MDR1 C3435T（exon 26）位点基因多态性对替米沙坦在原发性高血压患者中的稳态血药浓度及降压疗效的影响。方法：采用聚合酶链反应（PCR）和限制性内切酶片段多态性（RFLP）的方法对连续30 d每天口服40 mg替米沙坦的61名高血压患者的MDR1C3435T位点进行基因分型。使用高效液相色谱-荧光检测法（HPLC-FLD）测定高血压患者的稳态血药浓度,使用水银血压计测量治疗前、后高血压患者的血压值。比较不同基因型间高血压患者的稳态血药浓度及降压疗效的差异。结果：在61例中老年原发性高血压患者中,MDR1 C3435T CC型纯合子的频率为39.34%,TT型纯合子的频率为11.48%,CT型杂合子的频率为49.18%,MDR1C3435T位点等位基因发生率在健康人群和高血压患者间差异无统计学意义。3种基因型高血压患者的稳态血药浓度及降压有效率间差异无统计学意义（P〉0.05）。结论：MDR1 C3435T位点的基因多态性与高血压患者的稳态血药浓度及降压疗效间无相关性。     

CYP3A5和MDR1基因多态性对中国肝移植患者他克莫司药动学的影响

目的探讨细胞色素P450酶3A5（CYP3A5）基因和多药耐药基因（MDR1）C1236T、G2677T／A、C3435T多态性对肝移植患者口服他克莫司（TAC）后体内药动学参数的影响。方法采集28例肝移植患者手术后第1周和第3周血标本,采用LC—MS／MS法检测TAC血药浓度,计算主要药动学参数。采用聚合酶链反应结合基因测序分析28例肝移植患者CYP3A5＊3和MDR1主要基因型。结果携带MDR1 3435T基因型的肝移植患者口服TAC后,药动学参数AUC0→1和ρmax明显高于3435CC型患者,而CYP3A5＊3、MDR1 C1236T和G2677T／A基因多态性对TAC的药动学参数无明显影响。结论携带MDR1 3435T基因型肝移植患者比3435CC型患者需要较高剂量才能达到目标浓度。     

MDR1 C3435T基因多态性对环孢素体内代谢影响的荟萃分析

目的 过荟萃分析进一步观察MDR1 3435T 基因多态性对于环孢素体内代谢的影响。方法 过Pubmed搜索C3435T基因多态性对于环孢素体内代谢影响的相关文献，提取AUC0-4，AUC0-12，AUC0-inf,Cmax,CL/F,和C0等药物动力学参数，使用STATA9.1软件进行荟萃分析。结果 共有14篇参考文献，包括1036名受试者符合本次荟萃分析的入选争件，荟萃分析显示在C3435T野生型杂合子（CC）中，AUC0-12低于其他基因型的受试者。在白种人中，C3435T野生型杂合子（CC）携带者的C0低于其他基因型的白种受试者。其他药物动力学参数在C3435T各基因型之间未见显著差异。结论本荟萃分析没有发现MDR1 C3435T基因多态性对于环孢素体内代谢有较大的影响，但是观察指标的选择是观察结果差异的原因之一；MDR1 C3435T表型和基因型的相关性可能存在种族差异．     

肾移植患者MDR1C3435T基因多态性对他克莫司血药浓度/剂量比及疗效的影响

目的研究肾移植术后患者MDR1C3435T基因多态性对他克莫司（FK506）血药浓度／剂量比（C／D）及急性排斥反应和不良反应的影响。方法采用聚合酶链反应（PCR）和限制性内切片段长度多态性（RFLP）的方法检测肾移植患者MDR1C3435T基因型,比较不同基因型患者之间FK506的C／D值以及急性排斥反应、不良反应的差异。结果MDR1C3435T各基因型组间FK506的C／D值及急性排斥反应、不良反应均无显著性差异。结论MDR1C3435T基因多态性与肾移植患者FK506的C／D值及急性排斥反应、不良反应间无显著相关性。     

111例心衰患者的 MDR1 和CYP3A 基因多态性与地高辛血药浓度的相关性研究

目的：观察中国贵州地区汉族心衰患者中MDR1C3435T、CYP3A4＊18B和CYP3A5＊3等位基因多态性对地高辛血药浓度的影响。方法：收集111名中国贵州地区汉族心衰患者的血样与地高辛治疗药物浓度监测（TDM）数据,通过PCR-RFLP法分析患者的MDR1C3435T、CYP3A4＊18B及CYP3A5＊3基因型,分析每个基因的多态性对地高辛血药浓度的影响。结果：70岁以上患者MDR1各基因型组中,野生纯合子（CC）组、突变杂合子（CT）组、突变纯合子（TT）组的地高辛血药浓度依次增高。CC组和CT组较TT组的地高辛血药浓度差异有统计学意义（P〈0.05）;CYP3A4和CYP3A5各基因型组之间的地高辛血药浓度差异均无统计学意义（P〉0.05）。结论：MDR1C3435T等位基因突变可使地高辛血药浓度提高;而CYP3A4＊18B和CYP3A5＊3等位基因突变对地高辛的血药浓度无明显影响。     

ABCB1、CYP2B6基因多态性对丙泊酚血药浓度的影响

摘要：目的:探讨药物转运体ABCB1 C3435T与药物代谢酶CYP2B6 G516T基因多态性对丙泊酚血药浓度的影响,为丙泊酚临床个体化给药提供实验室数据。方法:采用荧光染色原位杂交法（FISH）,进行ABCB1 C3435T和CYP2B6 G516T基因多态性检测,用高效液相-荧光法检测血药浓度。根据不同基因型患者使用丙泊酚麻醉后30,60 min给药总量,比较基因多态性与丙泊酚标准化血药浓度的关系。结果:丙泊酚持续给药30 min时,ABCB1 C3435T三种基因型患者给药总量和标准血药浓度比较,差异无统计学意义（P>0.05）;丙泊酚持续给药60 min时,ABCB1不同基因型患者给药总量有明显差异（P<0.05）,ABCB1 C3435T野生纯合子CC基因型患者给药总量高于变异型（CT/TT）患者。给药60 min时,4组患者给药总量差异有统计学意义（P<0.05）。不同CYP2B6 G516T基因型患者在丙泊酚持续给药30 min和60 min时,给药总量和标准血药浓度无相关性。结论:ABCB1 C3435T基因多态性对丙泊酚血药浓度有影响,野生型患者为达到相同的血药浓度需要提高给药剂量。     

细胞色素P450 3A5和多药耐药基因遗传变异的联合效应对克拉霉素药代动力学的影响

目的 观察CYP3A5*3和MDR1 C3435T遗传变异的联合效应对中国健康受试者克拉霉素(大环内酯类抗生素)药代动力学的影响.方法 45名受试者服用单剂量克拉霉素胶囊250 mg,HPLC-MS法测定血药浓度.PCR-ASA法和PCR-RFLP法分别测定受试者CYP3A53和MDR1 C3435T的基因型,按基因型分组,比较基因多态性对克拉霉素药代动力学的影响.结果 在45名受试者中,CYP3A5*3各基因型分布,不受MDR1 C3435T基因型的影响;而2者的基因突变均不同程度地协同影响克拉霉素药代动力学参数Cmax、AUC0-24和tmax.结论 CYP3A5*3和MDR1 C3435T遗传变异及协同作用是影响克拉霉素药代动力学特性的重要因素.     

MDR1C3435T基因多态性对辛伐他汀稳态血药浓度及降脂疗效的影响

目的：研究高脂血症患者MDR1C3435T基因分布及其基因多态性对辛伐他汀稳态血药浓度及降脂疗效的影响。方法：115名高脂血症患者均给予每天20 mg的辛伐他汀治疗4周,在给药前及给药4周后取血样,采用PCR-RFLP（聚合酶链反应-限制性片段长度多态性分析）基因检测技术对MDR1C3435T等位基因进行分析,应用全自动生化分析仪和高效液相色谱仪分别测定血脂及辛伐他汀稳态血药浓度。结果：115名高脂血症患者MDR1C3435T基因型分布符合Hardy-Weinberg遗传平衡（P>0.05）,MDR1C3435T等位基因突变率为40.87％。野生纯合子基因（CC）型组、突变杂合子（CT）型组、突变纯合子（TT）型组之间辛伐他汀稳态血药浓度及降脂疗效无统计学差异（P>0.05）。结论：未发现MDR1C3435T基因多态性对辛伐他汀稳态血药浓度及降脂疗效有明显影响。     

肝移植中他克莫司的血药浓度与多药耐药基因多态性的关系

目的探讨肝移植术后患者的多药耐药基因（MDR1）C3435T、G2677T／A和C1236T位点的基因多态性对他克莫司（F1〈506）血药浓度的影响。方法使用荧光偏振免疫分析法（AxSYM）测定42例肝移植患者在术后1周和1个月时FK506的血药浓度,使用等位基因特异扩增法（ASA-PCR）对患者进行MDR1基因分型,比较不同基因型之间FK506的浓度／剂量比的差异。结果在42例患者中,C3435T中CC型16例（38．1％）,CT型23例（54．8％）,TT型3例（7．1％）;G2677T／A中CA;型4例（9．5％）,GT型13例（31．O％）,TT型8例（19．0％）,GA型7例（16．7％）,AT型10例（23．8％）;C1236T中CC型6例（14．3％）,CT型19例（45．2％）,TT型17例（40．5％）。根据移植术后第1周和第1个月的记录,在C1236T中CC型患者的浓度／剂量比小于CT型和TT型,且差异有统计学意义（P〈0．05）。在C3435T和G2677T／A中不同基因型之间的浓度／剂量比的差异无统计学意义（P〉0．05）。结论在肝移植患者中MDR1多态性与FK506血药浓度具有相关性,C1236TCC型患者拟取得相似的血药浓度要比CT型和TT型患者服用更高剂量的FK506。     

C3435T mutation in exon 26 of the human MDR1 gene and cyclosporine pharmacokinetics in healthy subjects

To determine the relationship between C3435T mutation in exon 26 of the human multidrug resistant 1 (MDR1) gene and cyclosporine pharmacokinetic parameters among healthy volunteers, the oral cyclosporine pharmacokinetic study was performed for 14 healthy subjects. Blood cyclosporine concentrations were measured by HPLC. Concentration-time data were analyzed by a noncompartmental method using WinNonLin, and the blood samples were genotyped for the C3435T polymorphism of MDR1 gene using the PCR and a restriction digest. Each cyclosporine pharmacokinetic parameter was compared using the Mann-Whitney U test according to his or her P-gp genotype. There were seven (7) homozygous C/C, six (6) C/T, and one (1) homozygous T/T genotypes in these 14 healthy volunteers. According to their genotypes, mean t(max) 1.6 +/- 0.3 hours, mean C(max) 1337 +/- 329 ng/mL, mean Cl/F 66.5 +/- 18.3 L/h, and mean AUC 5642 +/- 1577 ng.h/mL in C/C group and mean t(max) 2.0 +/- 0.6 hours, mean C(max) 1540 +/- 721 ng/mL, mean Cl/F 55.2 +/- 18.9 L/h, and mean AUC 6902 +/- 1405 ng.h/mL in C/T+T/T group. Although Cmax and AUC in C/T and T/T group were 15% and 22% larger than those in C/C group, none of these parameter comparisons was statistically significant. There were no statistical differences in cyclosporine pharmacokinetics among different MDR1 genotypes in these 14 healthy subjects.     

Digoxin pharmacokinetics and MDR1 genetic polymorphisms

BACKGROUND: The effect of MDR1 C3435T single nucleotide polymorphism (SNP) in exon 26 on digoxin pharmacokinetics has recently been challenged. OBJECTIVE. To clarify the relationships between MDR1 genetic polymorphisms in exon 26 (C3435T) and 21 (G2677T/A) and digoxin pharmacokinetics. MATERIALS AND METHODS: MDR1 genotypes for C3435T and G2677T/A SNPs were determined in 32 healthy subjects whose single oral dose digoxin pharmacokinetics had been measured over 48 h. RESULTS: A significant relationship was observed between C3435T SNP and digoxin AUCs ( p<0,05). Homozygous TT subjects had 20% higher digoxin plasma concentrations than CT and CC subjects and a trend for higher 48 h digoxin urinary recoveries (TT>CT>CC). Similar results, although not statistically significant, were observed from the MDR1 G2677T/A SNP. CONCLUSIONS: Our results confirm that the MDR1 C3435T single nucleotide polymorphism (SNP) significantly affects digoxin disposition kinetics, with homozygous TT subjects presenting the highest plasma concentrations.     

MDR1基因C3435T多态性对重症肌无力患者环孢素血药浓度的影响

目的 :研究MDR1基因C3435T多态性与重症肌无力患者环孢素药物动力学的关系。方法 :采用荧光PCR的方法检测 96名重症肌无力 (MG)患者MDR1C3435T基因型 ,其中临床资料较全的 73名 ,对其环孢素用药的血药检测结果与基因型结果分析。结果 :重症肌无力患者MDR1C3435T的分布频率接近 1:1;野生型 3435CC患者的环孢素全血谷浓度高于杂合型和突变型 (P <0 .0 5 ) ,杂合型与突变型之间无明显差异。结论 :药物遗传学研究对环孢素治疗重症肌无力患者的临床合理用药有指导意义。     

MDR1 haplotypes do not affect the steady-state pharmacokinetics of cyclosporine in renal transplant patients

This retrospective study investigated the impact of MDR1 haplotypes derived from the single-nucleotide polymorphisms (SNPs) 2677G>T (exon 21) and 3435C>T (exon 26) on the pharmacokinetics of cyclosporine in 98 renal transplant patients. Based on SNPs 2677 and 3435, four different haplotypes and nine different genotypes were identified in the study sample. Frequencies of SNPs, genotypes, and haplotypes were in agreement with previously reported values. Cyclosporine pharmacokinetics were characterized using a 2-hour AUC (AUC0-12), trough concentrations (C0), and blood concentrations 2 hours after cyclosporine administration (C2). No significant differences in dose-corrected AUC0-12, C0, or C2 values were observed between carriers of different SNP variants and genotypes (Kruskal-Wallis test), as well as between carriers and noncarriers of each haplotype (Mann-Whitney U test). Carriers of haplotype 12 (2677G and 3435T), which has previously been associated with increased digoxin AUC values, had a median AUC0-12 of 18.9 micro g*h*L-1 (range: 9.0-35.2) compared to 17.5 micro g*h*L-1 (range: 7.5-37.1) in the noncarrier group. It was concluded that MDR1 haplotypes derived from the SNPs 2677G>T (exon 21) and 3435C>T (exon 26) are not associated with cyclosporine pharmacokinetics in renal transplant patients.     

Meta-analysis of the influence of MDR1 C3435T polymorphism on digoxin pharmacokinetics and MDR1 gene expression

AIMS: Studies revealing conflicting results of the functional significance of MDR1 exon 26 C3435T SNP on the disposition of digoxin in different ethnic groups led us to perform a meta-analysis on published data investigating the influence of C3435T SNP on the pharmacokinetics of digoxin and the expression of MDR1. METHODS: Meta-analysis was performed on data from published studies investigating the influence of MDR1 C3435T SNP on digoxin pharmacokinetics, as well as MDR1 expression in Caucasian and Japanese populations. The following outcomes were included: exposures to digoxin measured by area under the concentration-time curve and maximum concentration, the mean intestinal MDR1 mRNA expression and P-gp expression in the absence of digoxin administration. RESULTS: The overall results of the meta-analysis in Caucasian and Japanese subjects suggested no major influence of the C3435T SNP on exposure levels of digoxin as determined by AUC(0-4 h) or AUC(0-24 h) although C(max) values for digoxin were lower in wild-type (CC) subjects compared with subjects harbouring TT genotypes. Subgroup analysis by ethnic populations showed the oral availability of digoxin to be lower in wild-type Caucasian populations compared with wild-type Japanese subjects. No causal relationships were detected between the C3435T SNP and MDR1 mRNA or protein expression. CONCLUSIONS: Our meta-analysis of available studies indicates that the synonymous MDR1 C3435T SNP does not affect the pharmacokinetics of digoxin and the expression of MDR1 mRNA. Future studies should focus on the impact of MDR1 haplotypes on the pharmacokinetics of MDR1 substrates rather than the C3435T SNP alone.