ABCC3基因表达及其mRNA剪接变异对氯吡格雷抵抗的影响

项目名称： ABCC3基因表达及其mRNA剪接变异对氯吡格雷抵抗的影响

项目编号： No.81473286

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 医药、卫生

项目作者： 谢红光

作者单位： 南京医科大学

项目金额： 85万元

中文摘要： 氯吡格雷抵抗的主要原因是肝脏生成的氯吡格雷活性产物减少。相关研究表明，外周血白细胞ABCC3/MRP3 mRNA表达增加与氯吡格雷抵抗有关，但其确切机制尚不清楚。我们的前期研究显示，ABCC3+/+小鼠生成的氯吡格雷活性产物较ABCC3-/-小鼠显著减少，进而产生较弱的抗血小板作用。已知人mRNA可变剪接可显著改变其表达与功能。据此推测人ABCC3 mRNA表达及其可变剪接可显著改变MRP3表达水平和肝细胞内氯吡格雷活性产物的生成量，进而参与氯吡格雷抵抗形成。本课题将系统研究多种ABCC3 mRNA剪接体在稳定转染细胞株的表达与功能改变，并在健康受试人群中研究这些剪接体与氯吡格雷活性产物血浓度和氯吡格雷抗血小板作用的相关性及其机制，明确ABCC3 mRNA可变剪接体与氯吡格雷抵抗在冠心病病人中的相互关系。此项目旨在阐明ABCC3 mRNA表达及其可变剪接参与氯吡格雷抵抗形成的新机制。

中文关键词： 氯吡格雷；氯吡格雷抵抗；ABCC3；可变剪接；冠心病

英文摘要： Clopidogrel resistance is a frequently encountered phenomenon in clinical settings. Accumulating evidence has demonstrated that the less formation of clopidogrel active metabolite in the liver is responsible for clopidogrel resistance, and that multidrug resistance-associated protein 3 (also known as MRP3) expressed in the liver mediates the export of some drugs from the hepatocytes to blood circulation, suggesting that a higher mRNA expression level of ABCC3 (which encodes MRP3) may be associated with the less generation of clopidogrel active metabolite in the liver. Our recent work indicated that the formation of clopidogrel active metabolite was less in the ABCC3+/+ mice than in the age- and gender-matched ABCC3-/- mice when the same dose of clopidogrel was given orally, with the former having a lower antiplatelet effect. We hypothesized that the higher expression levels of ABCC3 mRNA could play an important role in the less formation of clopidogrel active metabolite, and consequently clopidogrel resistance. It has been known that there are up to 17 alternative splicing variants of ABCC3 mRNA in human genome, resulting in marked polymorphisms in MRP3 protein structure and function, suggesting clopidogrel resistance in relation to increased ABCC3 mRNA expression levels or to greater portion of loss-of-function ABCC3 mRNA alternative splicing variant transcripts in total ABCC3 mRNA transcripts. This work was designed to classify all recruited healthy subjects and patients with coronary artery disease into four quartiles (Q1 - Q4), respectively, according to the descending order of inhibition of ADP-induced platelet aggregation before and after dosing of 300 mg clopidogrel. Clopidogrel-sensitive (Q1) versus clopidogrel-resistant (Q4) groups were chosen to compare between-group differences in the levels of ABCC3 mRNA expression, relative expression levels of each ABCC3 mRNA splicing variant of interest, and the plasma concentrations of clopidogrel active metabolite, respectively. This work would be used to clarify the potential relationship between polymorphic profiling of ABCC3 mRNA expression and the formation of clopidogrel active metabolite as well as clopidogrel resistance. These efforts would provide pharmacogenetic basis of personalized medicine of clopidogrel in patient care.

英文关键词： clopidogrel;clopidogrel resistance;ABCC3;alternative splicing;coronary artery disease