金丝桃苷对叠氮钠诱导PC12细胞凋亡的保护作用(英文)

目的:研究金丝桃苷对叠氮钠诱导的PC12细胞凋亡的保护作用。方法:将PC12细胞与不同浓度金丝桃苷共同孵育4h后,加入20mmol·L-1的叠氮钠继续孵育3～24h,观察金丝桃苷的保护作用。采用MTT、Hoechst33342分别检测细胞存活率和细胞形态变化。以Ac-DEVD-AMC为底物检测caspase-3活性,CM-H2DCFDA法用于测定ROS水平。Western blotting用于分析Bcl-2和Bax表达水平。结果:金丝桃苷在0.01,0.1及1μmol·L-1浓度时,可显著提高叠氮钠作用后PC12细胞的存活率,抑制细胞凋亡,减少细胞内活性氧自由基生成和caspase-3活性,提高抗凋亡蛋白Bcl-2表达,降低促凋亡因子Bax表达。同时结果显示caspase-3抑制剂呈时间依赖性地减少细胞内活性氧自由基含量。结论:金丝桃苷对叠氮钠诱导的PC12细胞凋亡具有保护作用,活性氧自由基生成与凋亡进程中caspase-3活性密切相关。

Neuroprotective Effects of Hyperoside on Sodium Azide-Induced Apoptosis in PC12 Cells

AIM：To investigate the neuroprotective effects of hyperoside （Hyp） on PC12 cells apoptosis induced by sodium azide and the mechanism of action.METHODS：To induce apoptosis,cultured PC12 cells was incubated with sodium azide 20 mmol·L^-1 for 3-24 h.Pretreatment with Hyp （0.01,0.1 or 1μmol·L^-1） for 4 h before sodium azide treatment.Cell viability was measured by MTT assay.The chromatin-specific dye Hoechst 33342 was used to observe nuclear changes.Caspase-3 activity was detected with a protease assay using Ac-DEVD-AMC as a substrate.Reactive oxygen species （ROS） was estimated by CM-H2DCFDA assay.Bcl-2 and Bax expression was determined by Western blotting.RESULTS：Pretreatment with Hyp （0.01,0.1 or 1μmol·L^-1） for 4 h attenuated sodium azide-mediated apoptosis,and the anti-apoptotic action of Hyp was partially dependent on suppressing the production of ROS,inhibition of caspase-3 activity and associated with increasing the expression of the anti-apoptotic protein Bcl-2,decreasing the expression of pro-apoptotic protein Bax.In addition,the caspase-3 inhibitor could reduce ROS formation in a time-dependent manner.CONCLUSION：The results suggest that Hyp has the neuroprotective capacity to attenuate sodium azide-induced apoptosis in PC12 cells.Our data also indicate that the generation of ROS is associated with the activity of caspase-3 during apoptosis.