Herpes simplex virus type induces β-amyloid expression in human neuroblastoma cell lines sh-sy5y / 第二军医大学学报

ABSTRACT

Objective To explore the effect of herpes simplex virus type (HSV-1) infection on expression of β-amyloid (Aβ) in human neuroblastoma cell lines SH-SY5Y. Methods African green monkey kidney cell lines Vero cells were used to amplified HSV-1, and the virus titers were measured. SH-SY5Y cells were infected with HSV-1 3.2×108 plaque forming unit (PFU)/mL at a multiplicity of infection (MOI) of 10 for 12 h or 24 h, and the morphological changes of the cells were observed under microscope. PCR was used to detect the expression of HSV-1 DNA. Double-color immunofluorescence assay was performed to show the expression of Aβ and apolipoprotein E (ApoE). Western blotting was used to detect the expression levels of amyloid precursor protein (APP), melanin metabolic enzyme (MME), ApoE, glycogen synthase kinase-3β (GSK-3β) and phosphorylated glycogen synthase kinase-3β (p-GSK-3β). Results After infection with HSV-1 for 12 h, the SH-SY5Y cells had synapse reduction and neurite retraction and few neurites. And after 24 h of infection, the cells began to aggregate, and were round and shed. Compared with phosphate buffer saline (PBS) control group, the expression of Aβ was significantly increased after infection with HSV-1 for 12 h (P0.01), while the expression of ApoE protein was not significantly changed. After 24 h of infection, the expressions of Aβ and ApoE were significantly increased (P0.05), but the expression of Aβ was significantly lower than that on 12 h of post-infection (P0.01). Western blotting analysis showed that, compared with PBS control group, the expression of APP was significantly decreased on 12 h of post-infection (P0.05), and the expressions of GSK-3β, p-GSK-3β and MME were significantly increased (P0.05). However, the expression of MME was significantly decreased (P0.05) and the expression of ApoE was significantly increased (P0.05) 24 h post-infection. Conclusion HSV-1 infection induces the expression of Aβ in SH-SY5Y cells through promoting APP metabolism and Ser9 phosphorylation of GSK-3β on 12 h of post-infection, and inhibiting the degradation of Aβ on 24 h of post-infection.