An in vitro antiviral evaluation of punicalagin toward influenza A virus

Influenza complications are mild to serious, and cancause death in some cases. A great deal of attention has been paidin recent years to the development and use of new antiviralcompounds to overcome drug resistance in certain strains of theinfluenza virus and treat the clinical implications. This studyaimedto investigate the antiviral effect of punicalagin and itsassociatedmechanism against influenza A (H1N1) virus in vitro.

the ant-influenza activity of punicalaginwas studied in Madin-Darby Canine Kidney (MDCK) cells usinginfluenza virus A/Puerto Rico/8/34 (H1N1) (PR8) usingHemagglutinin assay (HA) and 50% tissue culture infective dose(TCID50). Then, the inhibition of haemagglutination, virucidalactivity, inhibitory effect at different times, replication of viralRNA and expression of viral genes were investigated.

Punicalagin could inhibit influenza virus infection with50% inhibitory concentration (IC50) of 3.98 μg/ml and selectivityindex (SI) value of 6.1. Punicalagin decreased virus titers with aninhibitory effect on virus hemagglutination (p<0.05). Punicalaginalso inhibited viral adsorption. The results of virus RNAreplicationand viral mRNA (NS1 and HA) expression aftertreatment withpunicalagin showed significant suppression of viral mRNAexpression but no effect on replication of viral RNA.

The results of the present study indicated thatpunicalagin was effective against influenza infection mostprobablyvia inhibition of haemagglutination activity and virusbinding.