摘要
目的研究银杏内酯(Gin)预处理诱导 PC12细胞对缺血的耐受及相关机制。方法将大鼠肾上腺嗜铬细胞瘤 PC12株细胞随机分成对照组、缺血9 h 组、缺血预处理(IP)1.5 h+缺血9 h组和银杏内酯预处理+缺血9 h 组,用噻唑蓝比色分析、细胞形态学观察、Western 印迹法以及凝胶电泳迁移实验等方法比较银杏内酯预处理对 PC12细胞缺血模型的影响。结果在 PC12细胞缺血模型中,9 h 缺血可明显降低 PC12细胞活力,细胞存活率为(49.3±2.8)%。而银杏内酯24 h 预处理能显著提高9 h 缺血细胞的存活率(65.9±2.8)%(P<0.01);细胞形态学显示银杏内酯预处理后再缺血处理9 h,可明显减轻缺血9 h 所致的细胞损害,较多细胞保留突起,突起网络依然存在,胞体完好。与对照组比,银杏内酯预处理能明显增加缺氧诱导因子-1α(HIF-1α)蛋白表达(P<0.01);银杏内酯预处理诱导表达的 HIF-1具有生物学活性,它能与 DNA 结合,并激活下游基因促红细胞生成素(EPO)蛋白表达(P<0.01)。结论银杏内酯预处理可以诱导 PC12细胞对缺血的耐受,其诱导耐受的作用可能与银杏内酯预处理诱导 PC12细胞 HIF-1α稳定表达、提高 HIF-1与 DNA 结合活性以及增加其下游基因 EPO 蛋白表达有关。
Objective To explore the ischemic tolerance induced by Ginkgolides in PC12 cells and its possible molecular mechanism. Methods An ischemic model was developed in PC12 cell line with deprivation of oxygen-glucose（OGD）. PC12 cells was randomly divided into four groups： 9 hours ischemia group, 1.5 hours ischemic preconditioning ＋ 9 hours ischemia group, Ginkgolides preconditioning ＋ 9 hours ischemia group and control group. Cells viability was examined by MTT assay and cellular morphology was analyzed under the phase-contrast microscope. The molecular mechanism of Ginkgolides induced ischemic tolerance was pinpointedby analyzing the expression of hypoxia-inducible factor-1 α （HIF-1α） and erythropoietin （EPO）. The DNA binding activities of HIF-1 in PC12 cells were examined by electrophoretic mobility shift assay. Results In isehemic model, the viability of PC 12 cells was decreased （49.3± 2.8 ） % after OGD for 9 hours. However, Ginkgolides pretreatment could remarkably increase the viability of PC12 cells （65.9 ± 2. 8 ）% （P 〈 0.01 ）. Pretreatment of Ginkgolides for 24 hours could largely rescue the morphology of PC12 cells to the damage of subsequent exposure to 9 hours ischemia insult, many cellular bodies were intact and many neurites and network of PC12 cells were still exist. At molecular level, the expression of HIF-lα was greatly induced by Ginkgolides treatment after compared with the control group（ P 〈0.01 ）. The DNA binding activities of HIF-1 in PC12 cells pretreated with Ginkgolides was also increased. And it activates its downstream target EPO, the protein expression（ P 〈 0.01 ）. Conclusion The pretreatment of Ginkgolides could induce tolerance against ischemia in PC12 cells. The molecular mechanism of this process may involve in the activation of HIF-lα and the DNA binding activity of HIF-1 and its downstream target EPO.
出处
《中华医学杂志》
CAS
CSCD
北大核心
2007年第34期2432-2435,共4页
National Medical Journal of China
基金
江苏省高校自然科学基金(D4KJB310113)
作者简介
通讯作者：朱俐，Email：zhulizhou@ntu．edu．cn
