学术论文

      PI3K/Akt信号通路的异常活化对婴幼儿血管瘤内皮细胞凋亡的抑制作用

      Abnormal activation of PI3K/Akt signaling prevents the apoptosis of hemangioma-derived endothelial cell

      摘要:
      目的 对比婴幼儿血管瘤内皮细胞(HemEC)与普通的脐静脉内皮细胞(HUVEC)中PI3K/Akt信号通路活化状态,探讨其对HemEC凋亡的影响与机制.方法 无血清培养环境下诱导血管内皮细胞凋亡.应用Annexin V/PI双染流式细胞仪术、Hoechst33342与TUNEL荧光染色检测观察细胞凋亡的状态.采用Western blot技术检测VEGF、Akt与磷酸化Akt在HemEC和HUVEC中的表达或活化状态.应用PI3K抑制剂LY294002处理血清饥饿的血管内皮细胞,观察其对细胞凋亡的影响.结果 无血清培养12h后,可见HUVEC凋亡明显较对照组增多(P<0.05);,而HemEC凋亡增多不明显(P>0.05).无血清培养24 h或48 h后,HemEC中出现增多的凋亡细胞,但显著低于HUVEC(P<0.05).Western blot检测发现,与HUVEC相比,HemEC中Akt的活性显著升高.使用LY294002抑制HemEC中PI3K/Akt的活性后,HemEC凋亡率显著升高(P<0.05),而LY294002对HUVEC凋亡的影响不明显(P>0.05).结论 在离体细胞实验条件下,异常活化的PI3K/Akt信号通路能显著抑制缺血环境下的HemEC发生自发性凋亡.
      Abstract:
      Objective To explore the PI3K/Akt signaling pathway associated with the apoptosis of hemangioma-derived endothelial cell (HemEC).Methods HemECs and human umbilical vein endothelial cells (HUVECs) were subject to serum starvation for 12-48 hours.Cell apoptosis was measured by flow cytometry with annexin-V-fluorescein isothiocyanate/propidium iodide,Hoechst 33342 and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) staining.The expression of vascular endothelial growth factor (VEGF) and the activation of Akt were detected.And the potential mechanisms of PI3K/Akt inducing HemEC survival were examined.Results Compared with normal endothelial cells (HUVECs),HemECs showed increased resistance to apoptosis under serum starvation.The expression of endogenous VEGF and the activation of Akt markedly increased in HemECs compared with HUVECs in serum-free conditions.The activation of Akt was necessary for protection against serum starvation-induced apoptosis in HemECs.Inhibition of PI3K/Akt signaling decreased Akt activity and caused increased sensitivity to apoptosis in HemEcs.Conclusions Abnormal activation of PI3K/Akt signaling may be important for preventing in vitro apoptosis in HemECs.
      作者: 吉毅 [1] 陈思源 [2] 李凯 [3] 肖现民 [3] 郑珊 [3] 徐挺 [3]
      Author: Ji Yi [1] Chen Siyuan [2] Li Kai [3] Xiao Xianmin [3] Zheng Shan [3] Xu Ting [3]
      作者单位: 四川大学华西医院小儿外科 复旦大学附属儿科医院儿科研究所,上海,201102 复旦大学附属儿科医院外科,上海,201102
      刊 名: 中华小儿外科杂志 ISTICPKU
      年,卷(期): 2014, 35(2)
      在线出版日期: 2014年3月21日
      基金项目: 卫生部临床重点项目,复旦大学卓学计划,复旦大学研究生明道计划