DAPT attenuates ox-LDL-induced human umbilical vein endothelial cell injury

目的:; 探究gamma-分泌酶抑制剂N-[N-(3,5-difluorophenacetyl)-L-alanyl]-S-phenylglycine; t-butyl ester (DAPT)在氧化低密度脂蛋白(oxidized low-density lipoprotein,; ox-LDL)损伤人脐静脉内皮细胞(human umbilical vein endothelial; cells,HUVECs)模型中的细胞保护作用及其对Notch信号通路的调控。方法:体外培养HUVECs,用ox-; LDL处理HUVECs构建细胞损伤模型。实验分为对照组、ox-LDL处理组、DAPT处理组和DAPT +; ox-LDL处理组。用倒置相差显微镜观察不同处理方法下细胞的形态变化; CCK-8法检测细胞存活率; Western; blot法检测蛋白Notch1、Notch4和Jagged1的表达情况。结果:体外培养HUVECs,倒置相差显微镜下发现ox-LDL处理组细胞死; 亡和碎片增多,经DAPT预处理后,; ox-LDL作用造成的细胞损伤死亡较少,细胞碎片较少。通过CCK-8法检测发现ox-LDL处理组细胞存活率降低,DAPT处理组细胞存活率升高,D; APT预处理后ox-LDL造成存活率降低的幅度变小。在ox-LDL作用下,Notch1和Jagged1蛋白表达量降低,Notch4表达量升高;; 而DAPT作用下Notch1和Jagged1表达量升高,Notch4表达量降低; ox-LDL与DAPT共同作用时蛋白接近正常水平。结论:; ox-LDL对HUVECs具有损伤作用; DAPT减轻ox-LDL对HUVECs造成的损伤;; DAPT保护HUVECs免受ox-LDL损伤的作用与Notch信号通路有关。AIM: To investigate the effect of N-[N-(3,5 -difluorophenacetyl); -L-alanyl]-S-phenylglycine t-butyl ester (DAPT) on the Notch signaling; pathway in a model of oxidized low-density lipoprotein (ox-LDL) -induced; human umbilical vein endothelial cell (HUVEC) damage. METHODS: HUVECs; were divided into control group,ox-LDL group,DAPT group and ox-LDL +; DAPT group. The morphological changes of the HUVECs with different; treatments were observed under light microscope. The viability of the; HUVECs was measured by CCK-8 assay. The protein expression levels of; Notch1,Notch4 and Jagged1 were determined by Western blot. RESULTS:; ox-LDL induced great damage to the HUVECs,evidenced by increased cell; death and debris in the culture. However,the cell damage was abolished; by adding DAPT into the culture. The viability of the HUVECs was; increased by co-treatment with DAPT and ox-LDL. ox-LDL treatment; significantly decreased the protein expression levels of Notch1 and; Jagged1,and elevated Notch4. However,these changes were totally reversed; by DAPT. None of these proteins showed significant change in the HUVECs; co-treated with DAPT and ox-LDL as compared with control group.; CONCLUSION: ox-LDL is able to induce HUVEC damage in vitro. DAPT; attenuates ox-LDL-induced damage in the HUVECs by regulating the Notch; signaling pathway.厦门大学校长基金本科生项