摘要
目的 :研究大蒜素预处理对乳鼠心肌细胞缺氧复氧损伤的延迟保护作用及其部分信号转导机制。方法 :采用细胞存活率、乳酸脱氢酶活性、丙二醛含量作为心肌细胞受损指标 ,观察终浓度为 2 0 μg/ml的大蒜素预处理 2 4h后对乳鼠心肌细胞缺氧复氧损伤的保护作用及蛋白激酶抑制剂H 7、丝裂素激活蛋白激酶抑制剂PD 980 5 9对大蒜素预处理作用的影响 ;并通过免疫印迹技术(Westernblotanalysis)测定大蒜素预处理 2 4h后 ,nPKC ε、热休克蛋白 70 (HSP70 )和核因子 κB(NF κB)的表达情况。结果 :大蒜素预处理能显著提高缺氧复氧损伤心肌细胞存活率 ,减少LDH漏出和MDA生成 ,H 7、PD 980 5 9可完全取消这种心肌保护作用。大蒜素预处理可明显增加nPKC ε、HSP70的表达 ,H 7能抑制此作用 ,而PD980 5 9仅对HSP70表达有抑制 ,NF κB在各组间均无明显表达。结论 :大蒜素能够模拟缺血预处理延迟保护作用 ,其机制涉及PKC及MAPKs信号途径 ,可能通过活化nPKC ε ,使下游靶蛋白MAPKs磷酸化而诱导HSP70的高度表达产生延迟预处理心肌保护作用。
AIM: To investigate the cardioprotective effects and the mechanisms of delayed preconditioning of Allitridium on cultured neonatal rat myocardiocytes subjected to H/R.METHODS: Cultured neonatal rat cardiomyoctytes were preconditioned using Allitridum in final concentrations 20μg/ml.Cell viability, lactate dehydrogenase (LDH) release and malondialdehyde (MDA) formation were measured 24h late to determine the protective effects against H/R injury.And the expressions of nPKC-ε, HSP70 and NF-κB were measured 24h after preconditioning by western blot analysis.RESULTS: Increased cell viability, decreased LDH release and MDA formation were observed in cardiomyocytes treated with Allitridium.The delayed protection was abolished by pretreating with either PKC inhibitor H-7 or PD 98059(a upstream kinase inhibitor of MAPKs).And the expressions of nPKC-ε and HSP70 were significantly increased in APC group compared to control group which were abolished in APC+H-7 group, while only HSP70 increase was obviously restrained in APC+PD98059 group.CONCLUSION: Allitridium can mimick the delayed cardioprotection in rat neonatal cardiomyocytes.The protective mechanisms are associated with PKC and MAPKs signaling pathways.Allitridum induce delayed cardioprotective effects by activation of nPKC-ε, MAPKs(a dowmstream kinase of PKC) phosphorylation and followed increased expression of HSP70.
出处
《中国中医基础医学杂志》
CAS
CSCD
2004年第5期37-41,共5页
JOURNAL OF BASIC CHINESE MEDICINE
关键词
大蒜素
乳鼠
心肌细胞
信号转导机制
心肌保护
Allitridium
Delayed Preconditioning
Cardiomyocytes, Expressions of proteins
nPKC-ε
HSP70
NF-κB
