Fig 1. The cytotoxicity effects of AS-IV on the A549 cells. (A) Chemical structure of AS-IV. (B) CCK8 reagent was used to detect A549 cell viability. Cell viability was defined as the percentage of the 0μM group. (C) The growth of A549 cells was observed under the microscope. AS-IV, Astragaloside IV. *P < 0.05, ** P < 0.01.
A549 cells infected with the influenza virus (A/ PR/ 8/ 34 at 100 PFU) were treated with 50,75 and 100µM AS-IV. After influenza virus infection, the cells showed swelling, rupture, and dissolution, and the cell density was significantly lower than that of the NC group, AS-IV can significantly reduce the A549 cell death caused by viral infection (Fig. 2).