The Mechanism Of Autophagy And Apoptosis Induced By EV71 In Human Neural Cells SH-SY5Y

Objective: To demonstrate that EV71 can induce autophagy through mir-29 b and apoptosis,and preliminarily explore the possible mechanism of EV71 induced autophagy in neural cells.Methods: In vitro,the microarray technique was used to detect neural cell SH-SY5 Y which EV71 virus infected differentially expressed miRNAs;we tested some differentially expressed genes by qRT-PCR,and preliminarily confirmed that mir-29 b is associated with autophagy;finded the possible target gene PLD1 by bioinformatics;at the same time we used qRT-PCR,Western blot,confocal technique to detect autophagy in SH-SY5 Y cell infected with EV71;then we up-regulated the expression of intracellular mir-29 b by mir-29 b mimics to detect the changes of autophagy in SH-SY5 Y.The apoptosis of cells infected with EV71 was also detected.Results: The results of qRT-PCR showed that the EV71 could down-regulate the expression of mir-29 b in SH-SY5 Y cells,autophagy related gene beclin-1 was obviously up-regulated,the expression of p62 was decreased significantly;The results of Western blot showed that the expression radio of LC3II/LC3 I was increased in EV71 infected cells;in addition the results of confocal microtelescope indicated fluorescence concentration of intracellular GFP-LC3 increased with the EV71 infection time lapse.We up-regulated the expression of intracellular mir-29 b through transfected mir-29 b mimics,the Beclin-1 expression decreased,the expression level of p62 and PLD1 increased significantly;the ratio of LC3-II /LC3-I which is an important indicator of autophagy.Western blot results showed that the expression of cellular Bcl-2 decreased gradually with the infection time lapse;at the same time,the results of flow cytometry showed that among EV71 infected cells,the number of apoptotic cells increased significantly in a time dependent manner.Conclusion: The results suggested that EV71 can down regulate the expression of mir-29 b in cells,and induce apoptosis and autophagy in SH-SY5 Y cells;when we increase the expression level of mir-29 b in cells,the autophagy induced by EV71 inSH-SY5 Y can be reversed.All these results indicate that EV71 can induce autophagy and apoptosis in SH-SY5 Y cells,and the induction of autophagy is achieved through down-regulation of cellular mir-29 b.