【摘要】 目的 体外以缺氧无血清条件模拟心肌缺血微环境,观察银杏叶标准提取物(EGb761)能否抑制缺氧无血清诱导骨髓间充质干细胞(BMSCs)凋亡并探讨其机制。方法 分离培养BMSCs,用EGb761预处理30 min后,缺氧无血清培养12 h,应用Hochest 33258染色及膜联蛋白V/PI双染流式细胞术观察BMSCs凋亡,采用Western blot方法检测Procaspase-3表达。结果 流式细胞仪检测结果显示,与缺氧对照组比较,低剂量(10～100mg/L) EGb761处理组细胞凋亡率明显增高(P<0.01),高剂量(500-2 000 mg/L) EGb761组细胞凋亡率明显降低(P<0.01);Western blot检测结果显示,与缺氧对照组比较,低剂量EGb761组细胞Prcaspase-3表达降低(P<0.05),高剂量EGb761组Procaspase-3表达显著增高(P<0.05)。结论 EGb761对缺氧无血清诱导的BMSCs凋亡具有双重作用,其可能是通过caspase-3活化实现的。更多还原

【Abstract】 Objective To investigate the possible effect of Ginkgo biloba extract(EGb761) on the apoptosis of bone marrow mesenchymal stem cells(BMSCs) induced by simulated myocardial ischemic microenvironment with hypoxia and serum deprivation(Hypoxia/SD) in vitro and to explore the underlying mechanism.Methods BMSCs were isolated from bone marrow of Sprague-Dawley(SD) rats.Following pretreatment with EGb761 for 30 min and cell culture in serum-free medium with hypoxia for 12 h,cell apoptosis was detected by Hoechst 33258 staining and by flow cytometry with Annexin V-FITC/PI double staining,and the activation of procaspase-3 was detected by Western blot.Results Flow cytometric analysis showed that the low concentrations of EGb761(10-100 mg/L) increased the apoptotic rate of BMSCs compared with the hypoxia/SD group(P <0.01),whereas high concentrations of EGb761(500-2 000 mg/L)significantly decreased cell apoptosis when compared with the hypoxia/SD(P <0.01);Compared with the hypoxia/SD group,as indicated by Western blot,the level of procaspase-3 protein expression declined(P <0.05),while in the high-concentration EGb761 groups,expression of procaspase-3 was significantly upregulated(P <0.05).Conclusion EGb761 shows a biphasic effect on the hypoxia/SD-induced apoptosis of BMSCs,which is probably realized via the activation of caspase-3 signaling pathway.更多还原