不同还原性巯基氨基酸对人脐静脉内皮细胞的损伤作用研究

A Comparative Study of the Cell Damage Caused by Reduced Thiol Amino Acide in Cultured Endothelial Cells

目的 探讨三种还原性巯基氨基酸对培养人脐静脉内皮细胞的损伤效应。方法 将人脐静脉内皮细胞暴露于三种还原性巯基氨基酸 2 4小时后 ,测定细胞的乳酸脱氢酶释放率、总蛋白含量、凋亡及脂质过氧化的程度。结果 1同型半胱氨酸 (Hcy)不仅促进脂质过氧化 ,而且可诱导细胞凋亡并可致细胞坏死。 2谷胱甘肽(GSH)呈还原性 ,对细胞有全面的保护作用。 3Hcy的氧化性最强 ,GSH则呈现出完全的还原性 ,半胱氨酸 (Cys)可能处于二者之间。结论 同型半胱氨酸可能是通过特异的抑制谷光甘肽过氧化物酶并减弱了细胞内的还原缓冲能力等机制 ,发挥与 Cys和 GSH不同的生物学效应 ,从而导致内皮细胞出现坏死和凋亡等损伤性的改变。

Objective This study was intended to detail the effects of three redox thiol amino acids(Hcy,Cys and GSH) on cultured endothelial cells. Methods Human umbilical vein endothelial cells were cultured and exposed to Hcy,Cys and GSH. The lipid peroxidation, release of LDH and apoptosis were assessed. Results It was found that Hcy not only has strong effects on lipid peroxidation but also induces the apoptosis of endothelial cells and results in the necrosis of the cells. GSH is a reducing agent which protects endothelial cells and reduces oxidative injury. Hcy is the strongest oxide in these animo acids, GSH is conversely a reductor and the oxidative potential of Cys is between that of Hcy and GSH.Conclusion These things indicate that Hcy has a strong oxidizing effect, which may be one of its major mechanisms for the injury to endothelial cells,such as apoptosis and necrosis. And this bioeffect is different from that of Cys and GSH.