摘要
目的:研究p53-miR-34a-SIRT1反馈环在血管内皮祖细胞(EPC)复制性衰老过程中的调控作用及机制。方法:培养并鉴定由脐带血来源的EPC;观察第三代和第六代EPC在衰老、凋亡、周期和血管形成等方面的差异;检测第三代和第六代EPC中p53、乙酰化的p53(Ac-p53)、沉默信息调节因子2相关酶1(SIRT1)的表达情况;构建携带微小核糖核酸(miR)-34a抑制因子的慢病毒载体,明确外源性miR-34a抑制因子能否延缓第六代EPC的凋亡。结果:成功培养了脐带血来源的EPC。第六代EPC的衰老率和凋亡率明显高于第三代EPC,细胞周期主要停留在G0/G1期;第六代EPC的p53表达量高于第三代EPC,Ac-p53和SIRT1表达则相对较低,组间差异均有统计学意义(P均<0.05)。转染携带miR-34a抑制因子的慢病毒载体后,第六代EPC衰老情况有所改善,血管形成能力也增强,晚期凋亡率明显减少。结论:p53-miR-34a-SIRT1是EPC复制性衰老过程中的重要反馈调节机制,miR-34a抑制因子可能是延缓EPC衰老的靶点。
Objectives： To explore the modulating effects and related mechanisms of p53-miR-34 a-SIRT1 feedback loop in the process of replication senescence of vascular endothelial progenitor cells（EPC）. Methods： EPC derived from umbilical cord blood were cultured and identified. Differences on senescence, cell apoptosis, cell cycle and blood tube formation were observed in EPC of 3^rd and 6^th generation. Protein expression of p53, Acetyl-p53, and SIRT1 was also detected by Western blotting in EPC of 3^rd and 6^th generation. The miR-34 a inhibitor lentiviral vector was constructed and used to identify whether miR-34 a inhibitor can protect 6^th generation EPC from apoptosis. Results： EPC derived from umbilical cord blood were successfully cultured. The cells senescence rate and apoptosis rate of the 6^th generation EPC were significantly higher than those of the 3^rd generation EPC. The cell cycle of 6^th generation EPC was mainly arrested at G0/G1 phase. The protein expression level of p53 was significantly higher, while the protein expression of acetyl-p53 and SIRT1 was significantly lower in the 6^th generation EPC than in the 3^rd generation EPC, all P〈0.05. The senescence was significantly attenuated, and late apoptotic cells were significantly reduced, while angiogenesis ability was significantly enhanced in the 6^th generation EPC transfected with lentiviral vector carrying miR-34 a inhibitor.Conclusions： p53-miR-34 a-SIRT1 is an important feedback mechanism in the process of EPC replication senescence. The miR-34 a inhibitor may be the potential target of delaying EPC senescence.
作者
宋云林
谭秋婵
马燕
白林林
柴瑞峰
王毅
于湘友
SONG Yun-lin;TAN Qiu-chan;MA Yah;BAI Lin-lin;CHAI Rui-feng;WANG Yi;YU Xiang-you(Deparmaent of Critical Care Medicine, The First Affiliated Hospital of Xinjiang Medical University, Urumqi （830054）, Xinjiang, Chin)
出处
《中国循环杂志》
CSCD
北大核心
2018年第5期496-500,共5页
Chinese Circulation Journal
基金
新疆维吾尔自治区自然科学基金(2015211C065)
