Function of inhibition of RNA virus replication by digoxin and oleandrin

Abstract

Objective To evaluate the antiviral ability of cardiac glycosides of digoxin and oleandrin. Methods Human adenocarcinoma alveolar basal epithelial cell line （A549） and African green monkey kidney cell line （vero） were used for subsequent experiment. The cytotoxicity of cardiac glycosides of digoxin and oleandrin was assessed by CCK-8 assay. The effects of digoxin and oleandrin on the replication of vesicular stomatitis virus （VSV）， encephalomyocarditis virus （EMCV）， Sendai virus （SeV） and influenza A virus （H1N1） were determined by reverse transcription-real-time quantitative PCR （RT-qPCR） and Western blot. Vero cells with natural interferon （IFN） signaling pathway defects combined with fluorescence microscopy， RT-qPCR and Western blot were employed to analyze whether the antiviral mechanism of digoxin and oleandrin depended on IFN signaling pathway. In vero cells with ATP1A1 （sodium potassium ATPase protein 1） （ATP1A1-shRNA） knockdown， intracellular virus replication and antiviral IFN response were detected by RT-qPCR and Western blot. Results Digoxin and oleandrin could inhibit the expression levels of VSV， H1N1， SeV and EMCV mRNA. The combination of IFN-deficient vero cells demonstrated that digoxin and oleandrin played an antiviral role independent of IFN signaling pathway. Meantime， digoxin and oleandrin exerted no antiviral effect in vero cells with ATP1A1 knockdown. Conclusion Digoxin， oleandrin and other potent cardiac glycosides have a broad spectrum of antiviral capability mainly through the inhibition of Na+/K+ ion transporters intra- and extra-cell membrane.

Keywords

• |digoxin|oleandrin|antivirus|innate immunity|na+/k+-atpase|vesicular stomatitis virus|influenza a virus|respiratory virus|encephalomyocarditis virus