自噬在米诺环素保护PC12细胞氧糖剥夺-复糖复氧中的作用

目的: 探讨自噬在米诺环素保护PC12细胞氧糖剥夺-复糖复氧中的作用。方法: 构建PC12细胞氧糖剥夺-复糖复氧模型,采用米诺环素(MC,1、10、100 μmol/L)或3-甲基腺嘌呤(3-MA,5 mmol/L)进行干预,MTT检测细胞活力,单丹磺酰戊二胺(MDC)染色观察自噬泡,Western blot检测自噬相关蛋白Beclin1、微管相关蛋白轻链3(LC3Ⅱ)、泛素结合蛋白P62/SQSTM l的表达。结果: 氧糖剥夺处理后,1 μmol/L 和 10 μmol/L的MC能显著提高PC12细胞的存活率,而 100 μmol/L 则会加重细胞的损伤。蛋白LC3Ⅱ和Beclin1的表达与MC的浓度呈正相关性,自噬抑制剂3-MA能够降低LC3Ⅱ和Beclin1,增加P62/SQSTM l的表达逆转MC的保护作用。结论: 低剂量(1、10 μmol/L)MC能够通过增加LC3Ⅱ和Beclin1的表达,诱导PC12细胞产生自噬从而保护氧糖剥夺-复糖复氧处理后的PC12细胞。

Autophagy activation contributes to the protection of minocycline against oxygen-glucose deprivation and reperfusion in PC12 cells

AIM: To investigate the effects of autophagy on the protection of minocycline in PC12 cells after oxygen-glucose deprivation and reperfusion.METHODS: Cultured PC12 cells were exposed to oxygen-glucose deprivation and then reperfusion, and treated with minocycline (1, 10, 100 μmol/L) or trimethyladenine (3-MA,5 mmol/L) during reperfusion. Cell viability were determined by MTT assay after 6 h of reperfusion. We also stained cells with monodansylcadaverin to observe autophagic vacuole. The expression of protein LC3Ⅱ, Beclin1 and P62/SQSTM l were determined by western blot.RESULTS: Low dose (1, 10 μmol/L) minocycline significantly attenuated cell death cascades after oxygen-glucose deprivation, while the high dose (100 μmol/L) exacerbated the cell injury. The expression levels of LC3Ⅱ and Beclin1 increased more pronouncedly when PC12 cells were treated with minocycline at the higher concentration (1-100 μmol/L). The autophagy inhibitor 3-MA reversed the protection of minocycline by reducing the expression of LC3Ⅱ and Beclin1 and increasing P62/SQSTMl.CONCLUSION: The study suggests that minocycline promotes PC12 cells survival after oxygen-glucose deprivation and reperfusion, which might be mediated by up-regulating LC3Ⅱand Beclin1 expression and inducing autophagy.