Anti-Influenza Activity of an Ethyl Acetate Fraction of a Rhus verniciflua Ethanol Extract by Neuraminidase Inhibition

Figure 4

Determination of antiviral activity of RVS ethyl acetate fraction (RVSE) in MDCK and A549 cells. Viability of MDCK cells was assessed using MTS assay after treatment with indicated concentrations of RVSE (0–400 μg/mL) for 48 h (a). Antiviral activities of RVSE on influenza A/PR/8/34-GFP virus in MDCK cells. MDCK cells were treated with RVSE (12.5, 25, 50, and 100 μg/mL) before influenza A virus (A/PR/8/34-GFP) infection, and cells were incubated with medium alone (CON) or with 12.5, 25, 50, and 100 μg/mL of RVSE before A/PR/8/34-GFP () (b). GFP expression levels and reduction in viral replication using flow cytometry were assessed 24 h after viral infection in GHE-treated MDCK cells (c, d). A549 cells were treated with RVSE (12.5, 25, 50, and 100 μg/mL) prior to influenza A virus (A/PR/8/34-GFP) infection, and cells were incubated with medium alone (CON) or 12.5, 25, 50, and 100 μg/mL of RVSE prior to infection with A/PR/8/34-GFP () (b). GFP expression levels and reduction in viral replication using flow cytometry were assessed at 24 h after viral infection in GHE-treated A549 cells (c, d). Bar graph () statistics were determined by three experiments’ data using one-way ANOVA with Tukey’s post hoc test, ; . n.s.: not significant, compared with the (RVSE untreated) samples.

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