高糖和外源性硝化试剂导致人脐静脉内皮细胞蛋白质硝化的研究

High glucose and exogenous nitrating agents induced human umbilical vein endothelial cell injury:involvement of protein tyrosine nitration

采用细胞生物学及化学方法,检测了高浓度的糖和外源性硝化试剂作用于人脐静脉内皮细胞(ECV304)后所导致的细胞蛋白氧化损伤及硝化损伤.结果发现:高浓度的糖(30和40 mmol/L)可以导致细胞发生氧化损伤,主要包括降低细胞存活率、降低胞内还原型谷胱甘肽(GSH)的含量、增加胞内一氧化氮(NO)代谢产物亚硝酸盐和硝酸盐的含量;在细胞蛋白内也检测到蛋白质硝化的产物.研究发现:蛋白质硝化可以进一步加强细胞损伤的程度,而高浓度的糖和外源性硝化试剂导致的细胞蛋白硝化有所不同,其原因可能是在糖尿病血管并发症中蛋白质是有选择地发生硝化反应的.

Oxidative and nitrative injury in human umbilical vein endothelial cells （ ECV304 ） induced by high glucose and exogenous nitrating agent were detected by cell biological and chemical methods. It was found that high glucose （30 mmol/L and 40 mmol/L） stimulated ECV304 injury in a dose-dependent manner, including reducing cell viability, decreasing glutathione （ GSH ） content, increasing the production of nitric oxygen （NO） （increased nitrite content in cell and nitrate content in medium） and generating protein tyrosine nitration. It was also found that protein tyrosine nitration could induce cell injury further. Tyrosine nitration induced by high glucose was different from extrinsic factors. It could be speculated that protein was nitrated selectively to generate nitrotyrosine in diabetic vascular complications.