Figure 5

Determination of the anti-HEV effect of spicatoside A. (A) Spicatoside A structure. (B) Concentration-dependent inhibitory effects of spicatoside A on luciferase activity of the pSHEV3-luc replicon. Huh7.5 cells were mock-transfected or transfected with capped RNA transcripts from the pSHEV3-luc replicon and luc-pcDNA3. After incubation at 37 °C for 5 h, cells were treated with either DMSO or spicatoside A at concentrations of 0, 0.5, 1, and 2 µg/ml. Cells were re-treated with spicatoside A every 3 d after the initial treatment. At 4 d after treatment, luciferase activity was determined using a dual luciferase assay system. The luciferase activity of the pSHEV3-luc replicon was expressed in RLU by normalizing Renilla luciferase activity to constitutive firefly luciferase activity of luc-pcDNA3 transcripts. Relative luciferase activity was calculated by reference to luciferase activity of the pSHEV3-luc replicon in the presence of DMSO 4 d after transfection and defined as 100. P-values were determined by unpaired two-tailed Student’s t-tests (significant at ***P < 0.001). The data shown here represent six independent experiments.