同型半胱氨酸对心肌细胞的损伤作用及其信号转导机制探讨  

EFFECT OF HOMOCYSTEINE ON INJURY OF CARDIOMYOCYTES AND ITS SIGNAL TRANSDUCTION MECHANISM

作　　者：吴淑庆[1] 弓景波[1] 陈良恩[1] 钱令嘉[1] 

机构地区：[1]军事医学科学院卫生学环境医学研究所,天津300050

出　　处：《中国应用生理学杂志》2003年第1期25-29,T001,共6页Chinese Journal of Applied Physiology

基　　金：国家重点基础研究发展规划资助项目 (G2 0 0 0 0 56 9);国家自然科学基金资助项目( 39970 6 35)

摘　　要：目的 :观察同型半胱氨酸 (homocysteine ,HCY)对心肌细胞的损伤作用 ,探讨该作用发生的信号转导机制及其关键调控环节。方法 :分离培养Wistar乳鼠心肌细胞 ,经HCY作用后 ,以台盼蓝排斥实验测定细胞存活率 ,TUNEL法和流式细胞仪测定细胞凋亡率 ,免疫印迹法测定心肌细胞ERK2蛋白磷酸化水平 ,阻滞电泳法测定细胞NF κB活化水平。结果 :作用后 ,心肌细胞存活率显著降低 ,存活率降低程度与HCY的作用浓度、作用时间具有明确的剂量 效应关系及时间 效应关系 ;在 1 0 - 3mol/LHCY作用下 ,心肌细胞凋亡率升高 ,于 4h达峰值 ,为 7.56 % ;1 0 - 3、1 0 - 4、1 0 - 5mol/LHCY均可抑制心肌细胞ERK2磷酸化 ,其中 1 0 - 3mol/LHCY作用于心肌细胞后 ,ERK2蛋白磷酸化水平呈现迅速而明显的降低 ,4h降至对照组的 3 .0 4 % (P <0 .0 1 ) ;不同浓度HCY均明显阻抑NF κB的活化。结论 :HCY具有明显心肌细胞损伤作用 ,对心肌细胞凋亡的诱导是HCY心肌细胞损伤作用的形式之一 ;HCY可影响心肌细胞信号转导通路ERK ,并通过对转录因子NF κB的活化抑制 。AIM:To observe the injured effect of homocysteine (HCY) on cardiomyocytes and investigate its signal transduction mechanism as well as the key regulatory link. Methods:Cardiomyocytes were isolated from neonatal wistar rats. After incubation with HCY, the survival rate of cardiomyocytes was determined by trypan blue stained assay, while the apoptosis rate was measured by TUNEL and FCM. Western blot and EMSA were used to tested ERK2 protein phosphorylation and NF κB active expression in cardiomyocytes, respectively. Results:The survival rate of cardiomyocytes treated with HCY was reduced significantly in dose and time dependent manner. It was found that 10 -3 mol/L HCY could increase the apoptosis rate of cardiomyocytes to the peak (7.65%) at 4 h stress. Several HCY levels revealed the strong inhibility effect on ERK2 protein phosphorylation, especially, 10 -3 mol/L HCY decreased the level of active ERK2 expression to 3.04% of control at 4 h ( P <0.01). NF κB activition was also inhibited significantly by several HCY level for different time in cardiomyocytes. Conclusion:HCY plays an important role in injury of cardiomyocytes and apoptosis is a form of HCY induced injury to cardiomyocytes. HCY can block ERK2 protein phosphorylation and NF κB activation, which contribute to the injury of cardiomyocytes.dtotestedERK2 proteinphospho

关 键 词：同型半胱氨酸 心肌细胞 信号转导 

分 类 号：R363.1[医药卫生—病理学]