胞浆型磷脂酶A2介导弱氧化修饰低密度脂蛋白诱导的人脐静脉内皮细胞凋亡
DOI:
作者:
作者单位:

作者简介:

通讯作者:

中图分类号:

基金项目:

湖北省自然科学基金资助项目(2003ABA188).


Cytosolic Phospholipase A2 Mediates MM-LDL-induced Apoptosis in Human Umbilical Vein Endothelial Cells
Author:
Affiliation:

Fund Project:

This work was supported by a grant from The Natural Sciences Foundation of Hubei Province (2003ABA188).

  • 摘要
  • |
  • 图/表
  • |
  • 访问统计
  • |
  • 参考文献
  • |
  • 相似文献
  • |
  • 引证文献
  • |
  • 资源附件
  • |
  • 文章评论
    摘要:

    探讨弱氧化修饰低密度脂蛋白(MM-LDL)能否诱导人脐静脉内皮细胞(HUVECs)凋亡以及胞浆型磷脂酶A2(cPLA2)在此过程中的作用.MTT法测定细胞存活率;相差显微镜、荧光显微镜和流式细胞仪检测细胞凋亡;3H-花生四烯酸(3H-AA)预标法测定PLA2活性;蛋白质印迹检测cPLA2磷酸化;激光共聚焦显微镜检测单个细胞内钙离子浓度的变化.结果表明,MM-LDL(100~300 mg/L)作用后的HUVECs呈现凋亡典型的形态特征,凋亡率随MM-LDL浓度的增加而上升.MM-LDL能引起胞内钙离子浓度增加,cPLA2的活化及磷酸化.15 μmol/L AACOCF3和5 mmol/L EGTA在抑制cPLA2活性的同时,部分抑制MM-LDL诱导的HUVECs凋亡.加入外源性AA(50 μmol/L)能逆转AACOCF3引起的凋亡抑制.结果提示,cPLA2参与了MM-LDL诱导HUVECs凋亡的信号传递.

    Abstract:

    In order to investigate if minimally modified low-density lipoprotein (MM-LDL) could induce apoptosis in human umbilical vein endothelial cells (HUVECs) and the potential role of cytosolic phospholipase A2 (cPLA2) in this process. Cell viability was determined by MTT assay, cell apoptosis was assessed by phase-contrast microscopy, fluorescence microscopy and flow cytometry (FCM), PLA2 activity was determined by measuring the release of 3H-arachidonic acid (3H-AA) from prelabeled cells, phosphorylation of cPLA2 was analyzed using Western blot, changes of [Ca2+i in single cell were monitored by laser scanning confocal microscope (LSCM). The results showed that MM-LDL (100~300 mg/L) induced decrease in cell viability in a dose- and time- dependent manner. After 48 h exposure to 300 mg/L MM-LDL, apoptosis with cell shrinkage, chromatin condensation and nuclear fragmentation were observed. FCM assay showed that the apoptotic ratio rose with an increase in concentration of MM-LDL. MM-LDL caused a rapid elevation of [Ca2+i in HUVECs partly through calcium influx. Incubation with MM-LDL induced calcium-dependent cPLA2 activation companied with its phosphorylation. Inhibition of cPLA2 activity with 5 mmol/L EGTA or 15 μmol/L AACOCF3 reduced MM-LDL-induced apoptosis by 41.8% and 33.6%, respectively. Addition of exogenous AA (50 μmol/L) reversed AACOCF3-induced reduction of apoptosis. It was demonstrated that MM-LDL induced apoptosis in HUVECs. cPLA2 activated by increase in intracellular Ca2+ was involved in the signal pathway.

    参考文献
    相似文献
    引证文献
引用本文

王韻,周新,汪炳华,陈丽达,张冀,曹金秀.胞浆型磷脂酶A2介导弱氧化修饰低密度脂蛋白诱导的人脐静脉内皮细胞凋亡[J].生物化学与生物物理进展,2004,31(4):350-355

复制
分享
文章指标
  • 点击次数:
  • 下载次数:
  • HTML阅读次数:
  • 引用次数:
历史
  • 收稿日期:2003-09-28
  • 最后修改日期:2003-10-31
  • 接受日期:
  • 在线发布日期:
  • 出版日期: