抑制microRNA-22可通过调节SIRT1表达减轻氧化应激引起的血管内皮细胞损伤

Inhibition of microRNA-22 Could Antagonize the Injury Casedby Oxidative Stress in Vascular Endothelial Cells Via Targeting Sirt

目的探讨SIRT1及microRNA-22在氧化应激引起的血管内皮细胞损伤过程中的表达变化和机制。方法使用20μmol/L叔丁基过氧化氢(t-BHP)诱导人脐周静脉血管内皮细胞株(HUVEC)的氧化应激。Cell Tilter Blue细胞活性分析试验及流式细胞术检测氧化应激对HUVEC增殖及凋亡的影响。Western blot检测氧化应激状态下HUVEC SIRT1蛋白水平的变化,同时q RT-PCR分析氧化应激对HVEC microRNA-22水平的影响。通过转染microRNA-22 inhibitor抑制HUVEC的microRNA-22表达,并观察microRNA-22抑制对氧化应激状态下HUVEC SIRT1表达及细胞增殖的影响。结果 t-BHP诱导的氧化应激可诱导HUVEC的增殖抑制,且降低SIRT1的表达。氧化应激状态下,HUVEC的microRNA-22表达增高。抑制microRNA-22可以恢复氧化应激状态下HUVEC的SIRT1表达,减轻细胞增殖抑制。结论 microRNA-22通过调节SIRT1参与氧化应激引起的血管内皮细胞损伤,可作为动脉粥样硬化的潜在治疗靶点。

Objective To investigate the change of SIRT1 and microRNA-22 expression in vascular endothelial cel injury induced by oxidative stress.Methods 20 μmol/L t-BHP was used to induce oxidative stress injury. The proliferation and apoptosis of HUVEC under oxidative stress were detected with cell tilter blue assay and flow cytometry. The change of level SIRT1 was determined with Western blot. The level of microRNA-22 in HUVEC under oxidative stress was detected with qRT-PCR assay. The down-regulate of microRNA-22 in HUVEC,microRNA-22 inhibitor was transfected followed with cell tilter blue assay,the effect of microRNA-22 inhibition on HUVEC proliferation was observed. Results The oxidative stress caused by t-BHP could inhibit proliferation of HUVEC. Also,the level of SIRT1 decreased in HUVEC after treated with t-BHP. A high expression of microRNA-22 was observed in HUVEC under oxidative stress. Inhibition of microRNA-22 could recover the expression of SIRT1. Moreover, down-regulation of microRNA-22 could antagonize the proliferation inhibition induced by oxidative stress. Conclusion MicroRNA-22 could play a role in the HUVEC injury caused by oxidative stress via regulate SIRT1. It can be a potential therapy target for atherosclerosis.