Antiherpetic action of methanolic extract from Verbascum thapsus

ESCOBAR F.; SALAS M.; SABINI C.; ZANON S.; TONN C.; GIORDANO O.; SABINI L.

Tafi del Valle, Tucumán

Jornada; XXV Jornadas Científicas Organizadas Por La Asociación De Biología De Tucumán; 2008

The availability of a reduced number of antiviral drugs and the appearance of resistant strains because of the use of the former in long treatments have caused a difficult situation, especially when dealing with inmunocompromised patients with herpetic infections or with concomitant infection with HIV. This situation leads to the utilization of combined therapies as well as to an intensive search for new antiherpetic drugs, plants compounds being a good alternative. Objective: to analyze antiherpetic activity of methanolic extract (ME) prepared from Verbascum thapsus and elucidate which stage of the viral cycle was inhibited. The aerial parts of V. Thapsus from the Cordoba province were sequentially extracted with n-hexane, chloroform and methanol. Concentrated ME was evaluated on Vero cells for its cytotoxic and antiviral ability. Toxicity was quantified: MNCC and Cytotoxic Concentration 50% (CC50), by Red Neutral uptake (RN) and MTT salt reduction. The antiviral activity was evaluated by plaques reduction at different stages of Herpes suis type 1 replication. Results were expressed in (ìg/ml); MNCC: 850; CC50 (RN):1100 and CC50 (MTT):1417. ME exerted over 70% inhibition before adsorption and/or during viral adsorption and not after penetration (intracellular events). It also demonstrated virucidal activity. The index of selectivity (IS = CC50/IC50) of ME was higher than 18. Thus, this index suggests that ME may possess powerful chemical agents whose molecular characterization should be addressed and points to the potential applicability of ME as a natural antiherpetic chemotherapy.