SERPINC1基因热点区域突变与静脉血栓形成的关联及其导致易栓状态的分子机制研究

Venous thromboembolism (VTE) is a kind of disease caused by multiple factors. Antithrombin (AT) is a well-characterized anticoagulant enzyme, and AT abnormality is an important factor in VTE formation. Recently, some researches indicated that genetic component should play a more important role in the development of VTE. By using a deep resequencing strategy, we found the hotspot mutation area containing c.883G>A, c.881G>T, c.880C>T and c.881G>A within the linker peptide of exon 5 of SERPINC1 gene which encoding AT. By using a genotyping study, we found that c.883G>A mutation could have a 10.917-fold increased risk for VTE, and could lead to significantly decreased activity of AT, indicating that the hotspot mutations might be a genetic risk factor for VTE. In this proposal, we intend to clarify the correlation between the above mutations of SERPINC1 and the development of VTE by using a case-control study of involving a large number of participants. In addition, we intend to investigate the molecular mechanisms of VTE caused by the above mutations and the abnormality of exon region through cell experiments and mouse animal models. Individuals at high-risk for VTE will benefit from the results of this research through early diagnosis and prevention. And the molecular basis of VTE caused by the SERPINC1 mutations will provide new methods for anti-venous thrombosis targeting therapy.

静脉血栓栓塞症（VTE）是由多因素引起的静脉血栓形成和血栓栓塞的一类疾病。抗凝血酶（AT）是经典抗凝蛋白，AT异常是VTE形成的重要因素，但机制尚未明确。最近研究表明遗传因素在VTE的形成过程中极为重要；通过重测序我们在编码AT的SERPINC1基因5号外显子表达连接肽区域中发现了包含c.883G>A，c.881G>T，c.880C>T和c.881G>A的突变热点区域；初步基因分型研究表明c.883G>A对VTE形成优势比约为10.917，并可导致AT活性明显降低，提示上述热点区域位点突变可能是VTE形成的遗传危险因素。本项目拟在此基础上，通过大样本病例-对照研究明确SERPINC1基因上述突变位点与VTE形成的相关性，进而通过细胞实验及小鼠动物模型研究上述突变位点及其所在的外显子区域异常导致VTE形成的分子机制。研究有望服务于高危人群的静脉血栓风险筛查，为静脉血栓的靶向治疗提供新依据。

背景：静脉血栓栓塞（VTE）是第三大最常见的心血管并发症。越来越多的研究表明，一些microRNAs（miRNAs）在VTE中异常表达，并在介导VTE的发展中发挥关键作用。因此，我们的研究旨在探讨miR-200c-3p在VTE进展中的详细功能和分子机制。.研究内容：通过下腔静脉（IVC）结扎建立了VTE大鼠模型，并发现了IVC结扎对血栓形成的时间依赖性影响。逆转录定量聚合酶链反应（RT-qPCR）和蛋白印迹结果显示，在VTE大鼠模型中，SERPINC1表达下调，并与血栓负荷呈负相关。miRNA靶标预测工具和荧光素酶报告基因检测证实了SERPINC1是miR-200c-3p的靶点。给VTE大鼠注射miR-200c-3p抑制剂24 h，研究miR-200c-3p敲低是否影响体内血栓形成。.结果：苏木精-伊红染色的组织学检查显示，miR-200c-3p下调可显著抑制大鼠IVC血栓的形成。VTE大鼠血清和下腔静脉以及VTE患者血浆中miR- 200c-3p表达上调，而SERPINC1表达下调。线性回归分析显示，VTE大鼠和VTE患者中miR-200c-3p表达与SERPINC1表达呈负相关。.结论：确定之前未阐明的miR-200c-3p在VTE中的功能，这可能为VTE的治疗提供了一个潜在的新见解。