左卡尼汀对过氧化氢诱导的心肌细胞凋亡的抑制作用(英文)  

Inhibitory effect of L-carnitine on cardiomyocyte apoptosis induced by hydrogen peroxide

作　　者：梁春光[1] 戴红良[1] 黄雷 王东海 王洪新[1] 

机构地区：[1]辽宁医学院分子生物学与新药开发重点实验室,辽宁锦州121001 [2]锦州市食品药品检验所,辽宁锦州121000 [3]大同煤总医院,山西大同037003

出　　处：《中国药理学与毒理学杂志》2012年第5期602-609,共8页Chinese Journal of Pharmacology and Toxicology

基　　金：The project supported by Program for Liaoning Excellent Talents in University(2008RC33);vincial Office of Education Innovation Project Team(2007T113)~~

摘　　要：目的探讨左旋尼汀对心肌细胞凋亡的抑制作用及其可能的作用机制。方法采用培养的新生乳大鼠心肌细胞制备H2O2200μmol.L-1氧化损伤模型。实验分为正常对照组、H2O2200μmol.L-1模型组、左卡尼汀(0.3,0.6及1.2 mmol.L-1)组、左卡尼汀1.2 mmol.L-1+H2O2200μmol.L-1组。左卡尼汀0.3,0.6和1.2 mmol.L-1作用1 h后加入H2O2200μmol.L-1培养12 h,MTT法测定心肌细胞存活率,流式细胞仪测定心肌细胞的凋亡率,Western印迹法测定胱天蛋白酶3表达;用试剂盒方法检测过氧化物歧化酶(SOD)活性和丙二醛(MDA)水平。左卡尼汀1.2 mmol.L-1作用5 min后加入H2O2200μmol.L-1,采用Till阳离子测定系统监测5 min的心肌细胞[Ca2+]i瞬间变化。结果 H2O2200μmol.L-1作用于心肌细胞12 h能引起心肌细胞凋亡。左卡尼汀0.3,0.6和1.2 mmol.L-1能够不同程度的逆转由H2O2所致的损伤,使SOD活性明显增加,MDA水平明显降低(P<0.01)。左卡尼汀1.2 mmol.L-1作用最强,能够明显降低心肌细胞胱天蛋白酶3表达(P<0.01),明显降低H2O2引起的[Ca2+]i瞬间变化升高(P<0.01),但对于H2O2引起无钙血清培养的心肌细胞静息钙升高无影响。结论左卡尼汀能够抑制由H2O2引起的心肌细胞凋亡,该抑制作用可能与其保护细胞膜和减轻钙通道的损害、纠正[Ca2+]i瞬变失调及其抗氧化作用有关。OBJECTIVE To investigate the effect of L-carnitine on H2O2-induced apoptosis in cultured neonatal rat cardiomyocytes and its possible mechanisms.METHODS H2O2 200 μmol·L-1 was used to set up an oxidative stress induced injury model in neonatal rat cardiomyocytes.There were normal control,H2O2 200 μmol·L-1 model,L-carnitine（0.3,0.6 and 1.2 mmol·L-1）,L-carnitine（1.2 mmol·L-1）＋H2O2（200 μmol·L-1） groups in the experiment.The cells were pretreated with L-carnitine 0.3,0.6 and 1.2 mmol·L-1 for 1 h before H2O2 200 μmol·L-1 was added for 12 h.Cell viability was measured by MTT assay and apoptosis was determined by flow cytometry.The expression of caspase 3 was determined by Western blotting.Superoxide dismutase（SOD） and malondialdehyde（MDA） were measured according to the instructions of commercial kits.L-Carnitine 1.2 mmol·L-1 was added 5 min prior to H2O2 200 μmol·L-1.H2O2 was perfused for 5 min to measure i transient by Till image system by cell loading Fura-2/AM.RESULTS Application of H2O2 200 μmol·L-1 to myocytes for 12 h could cause cardiomyocyte apoptosis.L-Carnitine 0.3,0.6 and 1.2 mmol·L-1 significantly reversed the lesion of primary cultured cardiomyocytes treated with H2O2 200 μmol·L-1,increased SOD activity（P0.01）,and decreased MDA content（P0.01）.L-Carnitine 1.2 mmol·L-1 was the most powerful in that it decreased caspase 3 expression（P0.01） and the adverse effect of H2O2 on the i transient was abolished by L-carnitine pretreatment.L-Carnitine had no effect on the elevation of the resting i evoked by H2O2 in Ca2＋-free medium.CONCLUSION L-Carnitine can produce an inhibitory effect on cardiomyocyte apoptosis induced by H2O2,which may be mediated by the protective effect on the cell membrane and the damage to voltage-dependent Ca2＋ channel as well as its inhibition of lipid peroxidation.

关 键 词：左卡尼汀 过氧化氢 肌细胞 心脏 细胞凋亡 细胞内钙离子 

分 类 号：R965[医药卫生—药理学]