SIRT1调控转录因子KLF4影响内皮祖细胞分化的作用及机制研究

项目名称： SIRT1调控转录因子KLF4影响内皮祖细胞分化的作用及机制研究

项目编号： No.81070092

项目类型： 面上项目

立项/批准年度： 2011

项目学科： 轻工业、手工业

项目作者： 董红梅

作者单位： 中国人民解放军第三军医大学

项目金额： 10万元

中文摘要： 血管内皮修复不良是血管性疾病发展的关键因素，内皮祖细胞（EPCs）分化为成熟的内皮细胞是血管损伤后再内皮化的有效途径，但是，其分化的不定向性影响了修复效果。本课题通过三维细胞共培养体外模拟立体血管及颈动脉损伤模型，利用基因转染、小RNA干扰等技术，研究表明：1.从单一细胞水平发现沉默信息调节基因 （SIRT1）上调了EPCs分化过程中KLF4的表达;2.转录因子KLF4促进EPCs分化为成熟的内皮细胞，过表达KLF4促进EPCs的eNOS表达，培养液的NO增多，eNOS抑制剂，L-NAME减低了KLF4在EPCs分化为成熟内皮表型CD31、VWF的蛋白表达，抑制了血管新生;3.在细胞共培养体系中，KLF4基因修饰EPCs与平滑肌共培养明显抑制平滑肌的增殖和迁移，同时使平滑肌的P53蛋白表达增高，揭示KLF4转染的EPCs参与修复损伤血管的生物效应。进一步阐明KLF4影响EPCs分化修复损伤血管的作用及机制，这将为血管性疾病、血管再内皮化治疗提供新的策略和药物靶点。

中文关键词： 血管内皮；KLF4；SIRT1；损伤；修复

英文摘要： Dysfunction of the vascular endothelium is a vital factor in the pathogenesis of vascular disease. Endothelial progenitor cells (EPCs) differentiate into mature endothelial cells after vascular injury in an effective way of re-endothelialization. However, the mechanism of differentiation of EPCs remains uncertain that might effect the repair of endothelialization. This subject by the three-dimensional cell culture in vitro simulation of three-dimensional vascular and carotid artery injury model, the use of gene transfection, small RNA interference technology .Our research group found :1.From a single cell levelthe transcription factor KLF4 can promote differentiation of EPCs to endothelial.Overexpression of KLF4 upregulated the expression of eNOS protein and gene. The expression of eNOS protein was inhibited by the KLF4 siRNA .Moreover, L-NAME, which is an inhibitor of NOS, inhibited the induction of protein expression by KLF4 of CD31 and VWF in the EPCs and nearly attenuated the protein expression of these factors. The tube formation was significantly attenuated on treatment with L-NAME.2. The silent information regulator gene (SIRT1) played a role in the transcription factor KLF4.3.In the cell coculture system,KLF4 gene modified EPCs can inhibit VSMCs proliferation and and migration,and increase the protein exproeeion of P53 in VSMCs . KLF4 expression was significantly enhanced and larger the reendothelialized area in the Ad-KLF4-EPCs treated arteries after injury .Further clarify the role and mechanism of the the KLF4 impact of EPCs differentiate to repair the damage of blood vessels for the vascular disease, vascular reendothelialization treatment of new strategies and drug targets.

英文关键词： Vascular endothelium; KLF4; SIRT1; Injury; Repair