Efficacy of Bidens pilosa Extract against Herpes Simplex Virus Infection In Vitro and In Vivo
Effects of B. pilosa extract on RAW 264.7 cells. (a) Inhibition of HSV-1 replication by B. pilosa extract in RAW 264.7 cells. RAW 264.7 cells were infected with HSV-1 and left for adsorption for 1 h. They were washed and then incubated with 1000 μg/mL B. pilosa extract. At the indicated hours postinfection, both cell-associated and extracellular viruses were titrated by the plaque assay. Data represent mean ± SD of triplicate cultures. (b) Effect of B. pilosa extract on iNOS mRNA expression in RAW 264.7 cells. The cells were incubated with different concentrations of B. pilosa extract for 2 h. iNOS mRNA expression was detected by RT-PCR. (c) Effect of L-NAME on HSV-1 replication in RAW cells. Monolayers of RAW 264.7 cells were inoculated with HSV-1 and then treated with 1000 μg/mL B. pilosa extract in the presence or absence of 5 mM L-NAME. Cells and supernatants were harvested at 24–72 h after infection for titration of intracellular and extracellular HSV-1 and NO production. Data represent mean ± SD of triplicate cultures. n.d., not detected.