Survivin在PC12细胞对抗化学性缺氧损伤中的作用

目的探讨存活素(survivin)在PC12细胞对抗氯化钴(CoCl2)诱导损伤中的作用。方法应用不同浓度的CoCl2处理PC12细胞不同时间,建立化学性缺氧诱导PC12细胞损伤的实验模型。应用CCK-8比色法检测细胞存活率;Western-blot法检测CoCl2诱导缺氧与survivin表达间的量效(200～1000μmol·L-1)和时效(0～48h)关系。结果CoCl2可明显抑制PC12细胞的存活率,且呈浓度和时间依赖性。应用不同浓度CoCl2处理PC12细胞24h,在200～600μmol·L-1浓度范围内,呈浓度依赖性地促进survivin表达,600μmol·L-1CoCl2诱导survivin表达达高峰,超过此浓度,则随着CoCl2浓度的增加,survivin表达逐渐下降,CoCl2浓度达1000μmol·L-1时,survivin基本不表达;应用600μmol·L-1CoCl2处理PC12细胞,在0～36h时间范围内,呈时间依赖性地促进PC12细胞survivin的表达,但随着处理时间的延长,survivin的表达逐渐下降;加入2μmol·L-1Hsp90抑制剂17-丙烯胺基-17-去甲氧基格尔德霉素(17-AAG),不仅可以降低600μmol·L-1 CoCl2诱导的survivin高表达,而且加重了600μmol·L-1 CoCl2对PC12细胞的损伤作用,使细胞存活率降低。结论survivin表达上调可能是PC12细胞对抗化学性缺氧损伤的内在防御机制之一。

Role of survivin in PC12 cells against injuries induced by chemical hypoxia

Aim To explore the effect of survivin in PC12 cells against injuries induced by cobalt chloride(CoCl_2).Methods PC12 cells were exposed to CoCl_2 at different doses in different time to set up the chemical hypoxia induced PC12 cells injuries model.Cell viability was tested by using cell counter kit-8.Dose-effect(200～1 000 μmol·L~(-1))and time-effect(0～48 h)relationship between hypoxia induced by CoCl_2 and the expression of survivin was evaluated by western blot.Results PC12 cells viability was inhibited significantly by CoCl_2 in a dose and time dependent manners;At the concentrations from 200 to 600 μmol·L~(-1) CoCl_2 for 24 h,survivin expression was upregulated in a dose dependent manner,peaking at 600 μmol·L~(-1) CoCl_2 treatment,exceeding this concentration of CoCl_2,with dose increasing,survivin expression decreased.At the dose of CoCl_2 up to 1 000 μmol·L~(-1),survivin did not express basically;Treatment with 600 μmol·L~(-1) CoCl_2 in different time,within the range of 0～36 h,the expression of survivin enhanced in time dependent manner.But with the extension of time,survivin expression was declining; 17-allylamino-17-demethoxygeldanamycin (2 μmol·L~(-1)),an inhibitor of Hsp90,not only decreased survivin overexpression but also obviously enhanced the injuries of PC12 cells induced by CoCl_2,which didn't damage PC12 cells alone.Conclusion Upregulation of survivin expression may be one of the endogenous defense mechanisms for PC12 cells against chemical hypoxia.