卡维地洛对氧化低密度脂蛋白诱导血管内皮细胞ADMA-DDAH系统的影响  

Effects of carvedilol on metabolic mechanism of endogenous NOS inhibitor in human umbilical vein endothelial cell induced by oxidized low density lipoprotein

作　　者：夏子荣[1] 万磊[1] 李菊香[1] 颜素娟[1] 苏海[1] 罗伟[1] 程晓曙[1] 

机构地区：[1]南昌大学第二附属医院心内科,南昌330006

出　　处：《江西医药》2007年第3期198-200,共3页Jiangxi Medical Journal

基　　金：江西省自然科学基金研究项目(0340102)

摘　　要：目的观察卡维地洛对氧化低密度脂蛋白（ox-LDL）诱导的人脐静脉内皮细胞（HUVECs）二甲基精氨酸-二甲基赖氨酸水解酶（DDAH）活性及表达的影响,以探讨卡维地洛对内源性一氧化氮合酶抑制物不对称二甲精氨酸（ADMA）代谢机制的影响。方法采用改良的Jaffe法培养原代人脐静脉内皮细胞（HUVECs）,取生长良好的3-6代HUVECs用于实验,分为（1）空白对照组：加DMEM培养液;（2）ox-LDL组：加入ox-LDL（100mg/L,150mg/L）;（3）ox-LDL＋卡维地洛组：同时加入150mg/L ox-LDL及卡维地洛（10μmol/L）共孵24h后,检测上清液中NO、NOS活性、ADMA含量、L-胍氨酸（L-cit）浓度,采用Western blotting测定细胞裂解液中二甲基精氨酸-二甲基赖氨酸水解酶（DDAH）的蛋白表达。结果ox-LDL条件培养下,内皮细胞的代谢产物ADMA、ET的量均较空白对照组高,而NO的量及NOS的活性减少;反应DDAH酶活性的L-cit浓度显著降低,且有浓度依赖性,而DDAH的表达无明显变化。卡维地洛干预后,ADMA、ET的量较ox-LDL组降低,NOS活性及NO增加,L-cit浓度明显升高。结论ox-LDL诱导下,内皮损伤ADMA的增加与DDAH的活性减弱有关,而与DDAH的表达无关。卡维地洛通过增加DDAH活性促进ADMA代谢,使NOS活性增高,抑制ox-LDL对内皮功能的损伤。Objective To probe the effects of oxidized low density lipoprotein （oxLDL） on dimethylarginine dimethylaminohydrolase （DDAH） activity and concentration of human umbilical vein endothelial cells （HUVECs）,and investigate the metabolic mechanism of endogenous NOS inhibitor and the role of Carvedilol.Methods HUVECs of 3- 6th passage, cultured with modified Jaffes＇ method, were divided into three groups： （1） cells cultured with equivalent DMEM medium as control;（2） oxLDL intervention groups, were added 100mg/L, 150mg/L oxLDL respectively;（3） drug intervention groups：150mg/L oxLDL groups were added 10μmol/L Carvedilol.ADMA, nitric oxide（NO）, endothim（ET）,L-cit concentrations and the activity of NOS in conditioned medium were measured after 24h exposure. ADMA concentration in the conditioned medium was determined by high-performance liquid chromatography.Western blotting was performed to evaluate DDAH expression.Results Compared with control group,ADMA and ET concentrations were increased, while the level of NO and the activity of NOS decreased and relevant to the concentrations of oxLDL.We assayed DDAH activity by determining L-citrulline formation from ADMA.The concentration of L-cit was decreased,while the DDAH expression had no obvious change. With the role of Carvedilol,ADMA,ET concentrations were decreased, while the level of NO, L-cit and the activity of NOS increased.Conclusion Endothelial dysfunction induced by oxLDL is associated with the increase of ADMA concentration and reduction of DDAH activity, but not DDAH expression. Carvedilol can promote the degradation of ADMA through increasing activity of DDAH and improve endothelium function.

关 键 词：氧化低密度脂蛋白 内皮细胞 不对称二甲精氨酸 DDAH 卡维地洛 

分 类 号：R-33[医药卫生]