人脐带内皮细胞受到血流剪切应力刺激后表达凋亡蛋白X连锁抑制物(英文)

X-linked inhibitor of apoptosis protein is regulated by lamin ar shear stress in cultured endothelial cells

目的 生理水平的血流剪切应力有抑制内皮细胞凋亡等作用 ,进而发挥抗动脉粥样硬化作用 ,本研究的目的是阐明血流剪切应力抑制血管内皮细胞凋亡的分子机制。方法 人脐静脉内皮细胞培养于DMEM培养液 ,当细胞融合时将细胞暴露于 2 0dyne·cm-2 的剪切应力 ,分别用免疫印迹杂交及实时聚合酶链反应法检测凋亡蛋白X连锁抑制物 (X linkedinhibitorofapoptosisprotein ,XIAP)mRNA及蛋白的表达。结果 2 0dyne·cm-2 的剪切应力刺激 1～ 4h ,可诱导内皮细胞产生XIAPmRNA ,4h时表达最多。 2 0dyne·cm-2 剪切应力刺激 6,1 2和 2 4h ,XI AP蛋白表达明显增加。结论 生理水平的剪切应力明显诱导内皮细胞XIAPmRNA和蛋白的表达 ,这可能是剪切应力抑制内皮细胞凋亡 。

AIM Physiological levels of laminar shear st ress inhibit apoptosis of endothelial cells and exert a potent antiatherosleroti c effect. However, the mechanisms which regulate shear stress-mediated inhibiti on of apoptosis remain to be fully clarified. METHODS Cultured hum an umbilical vein endothelial cells (HUVEC) were cultured and exposed to laminar shear stress, X-linked inhibitor of apoptosis protein (XIAP) mRNA and protein expression were observed by real-time polymerase chain reaction and Western blo tting analysis respectively. RESULTS Both XIAP mRNA and prote in expression were induced in cultured HUVEC after subjected to laminar shear s tress 20 dyne·cm -2 . XIAP mRNA expression increased from 1-4 h, and reached to the peak at 4 h. XIAP protein expression increased after exposure to shear s tres s for 6, 12 and 24 h. CONCLUSION The present study provides the fir st evidence that physiological levels of laminar shear stress induce XIAP expres sion in cultured endothelial cells, upregulation of XIAP may contribute to the p otent antiatherosclerotic effect of shear stress by preventing apoptosis of endo thelial cells.