Interferonogenic and antiviral effect of extracts from Erodium cicutarium. II. Modulatory activity of Erodium cicutarium extracts.

Methanol extract from Erodium cicutarium was shown not to induce interferon in a suspension of human leukocytes or in the cutaneo-muscular tissue of human embryo. It appeared to have no influence, either direct or cell-mediated, on interferon activity. However, it exerted stimulatory effect on the synthesis of interferon induced with Newcastle disease virus in cell cultures. The stimulation occurred irrespective of the time of methanol extract administration (before or after viral inducer). In the in vivo experiments, methanol extract injected intravenously induced interferon in mice. When given 24 h prior to Newcastle virus, it increased the titer of induced interferon determined in the animal serum collected 6 h after the virus injection. Besides, in the experimental viral infection in mice replication of influenza A virus in the lung tissue of infected animals was inhibited only when the mice were treated with methanol extract 24 and 48 h after infection with the virus.