Berberine inhibits enterovirus 71 replication by downregulating the MEK/ERK signaling pathway and autophagy

Background: The MEK-ERK signaling pathway and autophagy play an important role for enterovirus71(EV71) replication. Inhibition of MEK-ERK signaling pathway and autophagy is shown to impair EV71 replication. Berberine (BBR), an isoquinoline alkaloid isolated from Berberis vulgaris L., has been reported to have ability to regulate this signaling pathway and autophagy. Herein, we want to determine whether berberine can inhibit EV71 infection by downregulating the MEK/ERK signaling pathway and autophagy. Methods: The antiviral effect of berberine was determined by cytopathic effect (CPE) assay, western blotting assay and qRT-PCR assay. The mechanism of BBR anti-virus was determined by western blotting assay and immunofluorescence assay. Results: We showed that berberine does-dependently reduced EV71 RNA and protein synthesis, which was, at least in part, the result of inhibition of activation of MEK/ERK signaling pathway. Furthermore, we found that berberine suppressed the EV71-induced autophagy by activating AKT protein and inhibiting the phosphorylation of JNK and PI3KIII. Conclusions: BBR inhibited EV71 replication by downregulating autophagy and MEK/ERK signaling pathway. These findings suggest that BBR may be a potential agent or supplement against EV71 infection.