Avaliação in vitro da atividade antiviral, virucida e imunomoduladora de extratos alcoólicos de Echinacea angustifolia contra vírus de interesse veterinário

Abstract

Echinacea angustifolia is an herbaceous, perennial plant belonging to the Asteraceae family that has been used for centuries by Native Americans as an "anti-infective" in various viral and bacterial diseases. Infectious-contagious diseases of viral etiology are among the most important diseases that affect humans and animals, representing mainly a public health hazard. Particularly, viral diseases are associated with important diseases in several animal species causing huge economic impact to the industry. In this sense, this study aimed to evaluate the in vitro antiviral and virucidal activity of alcoholic extracts 20% of the phytotherapy E. angustifolia at 0.25% and 0 .5% against BoHV-1, BVDV and CCoV. For this, a cytotoxicity assay was initially performed and, later, evaluation of the antiviral and virucidal activities. Furthermore, in order to verify the relative expression of mRNA in MDBK cells treated with E. angustifolia, the quantitative PCR technique was performed for the cytokines IFNα and IFNβ. E. angustifolia at 0.5% showed antiviral activity against BoHV-1, BVDV and CCoV after 1, 3, 6 and 24 hours of treatment (p<0.05). In addition, E. angustifolia at 0.25% showed antiviral activity against BoHV-1 after 1 hour of incubation (p<0.05), but not against BVDV (p>0.05). The compound at same concentration and time resulted in an increased relative expression of IFNα mRNA in MDBK cells (p<0.05). E. angustifolia at 0.5% did not show virucidal activity against BoHV-1. Overall, the results showed that the herbal medicine E. angustifolia at 0.25 and 0.5% showed in vitro antiviral activity against BoHV-1, BVDV and CCoV. Further studies in vitro and in animal models are needed in order to elucidate its exact mechanism of action.