5-羟基-1-氢-吲唑对SH-SY5Y细胞的保护作用及其机制研究

The protective action and its mechanism of 5-hydroxy-1H-indazole in SH-SY5Y cells

目的研究5-羟基-1-氢-吲唑对1-甲基-4-苯基-吡啶离子(MPP^+)诱导凋亡的SH-SY5Y神经细胞的保护作用及其可能的作用机制。方法以MPP^+诱导SH-SY5Y细胞凋亡建立体外帕金森病细胞模型,以MTT法筛选药物有效保护浓度;以免疫化学染色以及Hoechst 33258核染研究药物的神经保护作用以及抗凋亡作用;以Western blot法检测与神经元凋亡密切相关的磷酸化tau蛋白及其上游激酶磷酸化糖原合成激酶(P-GSK-3β)和周期依赖性蛋白激酶5(cyclin dependent kinase,CDK5)的表达。结果 MPP+可引起GSK-3β的活化以及CDK5活性升高,诱导tau的异常磷酸化和神经细胞凋亡;而5-羟基-1-氢-吲唑可下调GSK-3β与CDK5的活性,降低磷酸化tau的水平和抑制MPP+导致的SH-SY5Y细胞的凋亡。结论 5-羟基-1-氢-吲唑可抑制MPP+引起的SH-SY5Y神经细胞凋亡,作用机制可能是通过同时抑制GSK-3β和CDK5两条信号传导通路,而降低tau蛋白的磷酸化水平,进一步发挥神经元保护作用。

Aim To study the protection and possible mechanism of 5-hydroxy-1H-indazole against 1-methyl-4-phenylpyridinium iodide(MPP^+)-induced SH-SY5 Y cell apoptosis.Methods An apoptotic model was established in human neuroblastoma SH-SY5Y by MPP^+ in vitro.MTT analysis was used to evaluate the protective effect of 5-hydroxy-1H-indazole.Immunochemistry and Hoechst33258 nuclear staining were used to observe the neuroprotection and anti-apoptosis of 5-hydroxy-1H-indazole.Western blot was used to detect the levels of P-tau(Ser396) closely related to neuronal apoptosis and its upstream kinases: P-GSK-3β and CDK5.Results MPP+induced activation of GSK-3β,increase of activity of CDK5,tau hyperphosphorylation and neuronal cell apoptosis.However,5-hydroxy-1H-indazole reduced the activities of GSK-3β and CDK5,then decreased the level of tau hyperphosphorylation and inhibited MPP+-induced SH-SY5 Y cells apoptosis.Conclusions 5-hydroxy-1H-indazole could attenuate MPP+-induced SH-SY5 Y neuronal cell apoptosis.Possible mechanism is that 5-hydroxy-1H-in-dazole inhibits GSK-3β and CDK5 two signal transduction pathways to lower the level of tau phosphorylation,then plays a role of neuroprotection.