神经节苷脂对脂多糖损伤大鼠嗜铬细胞瘤细胞的保护作用

目的：研究内源性神经节苷脂对大鼠嗜铬细胞瘤细胞株（PC12）脂多糖（LPS）损伤后的作用及机制。方法：培养PC12细胞，建立LPS损伤模型，采用MTT法检测不同浓度LPS对PC12细胞存活率的改变、葡萄糖神经酰胺合成酶抑制剂D（D-PDMP）耗竭内源性神经节苷脂时LPS对PC12细胞存活率的改变以及添加外源性神经节苷脂GM1后对PC12细胞存活率的保护作用；倒置显微镜和荧光显微镜观察细胞状态；RT-PCR检测NF-κB的相对表达含量。结果：LPS能导致PC12细胞形态学的改变及存活率下降，且随着LPS浓度的增加细胞存活率逐渐降低；神经节苷脂GM1能明显改善LPS所致的细胞形态学以及存活率的改变；工具药D-PDMP耗竭内源性神经节苷脂后，LPS对PC12细胞的损伤更严重，添加外源性神经节苷脂GM1，细胞形态学及存活率得到明显改善，细胞存活率上升；LPS损伤时细胞内NF-κB含量增加；D-PDMP预先耗竭内源性神经节苷脂时NF-κB含量增加更多；添加外源性神经节苷脂GM1后NF-κB含量降低。结论：内源性神经节苷脂对PC12细胞LPS损伤具有保护作用，可能是通过NF-κB信号通路来发挥作用的。

The protective effects of gangliosides on LPS-induced PC12 cells injury

Objective:To investigate the protective effects of endogenous gangliosides on LPS-induced PC12 cells injury and its possible mechanism. Methods:PC12 cells were cultured, and lipopolysaccharide(LPS) injury model was established. We detected the changes in sur-vival rate of different concentrations of LPS on PC12 cells, and the changes in survival rate of LPS when endogenous gangliosides were exhaust-ed by D-threo-1-phenyl-2-decanoylamino-3-morpholino-1-propanol(D-PDMP), and the protective effects of monosialoganglioside (GM1) on LPS-induced PC12 cells injury. Meanwhile, we observed the morphological changes of GM1 on PC12 cells induced after LPS injury by inverted microscope and fluorescence microscope, and then we detected the relative expression of NF-κB. Results:LPS could decrease the survival rate of cells in a concentration-dependent manner, and GM1 could significantly protect the cells against the changes in survival rate and morphologi-cal damages induced by LPS; After depletion of endogenous gangliosides by D-PDMP, LPS had more injury to PC12 cells, which could be im-proved by adding GM1; RT-PCR results showed that the relative expression of NF-κB in PC12 cells was increased in LPS group, while relative expression of NF-κB increased much higher when endogenous gangliosides were exhausted by D-PDMP, and the relative expression of NF-κB was decreased after GM1 being added. Conclusion:The endogenous gangliosides might through NF-κB signal pathway to protect PC12 cells a-gainst LPS-induced injury.