Evaluation of antiviral activity of aqueous extracts from Achyrocline satureioides against Western equine encephalitis virus

• Published in: Natural product research Vol. 26; no. 5; pp. 405 - 415
• Main Authors: Sabini, María Carola, Escobar, Franco Matías, Tonn, Carlos Eugenio, Zanon, Silvia Matilde, Contigiani, Marta Silvia, Sabini, Liliana Inés
• Format: Journal Article
• Language: English
• Published: England Taylor & Francis Group 01.03.2012
• Subjects: Achyrocline - chemistry; Achyrocline satureioides; Adsorption; Animals; Antiviral activity; Antiviral Agents - chemistry; Antiviral Agents - pharmacology; aqueous extracts; Asteraceae; Cercopithecus aethiops; Cytotoxicity; Encephalitis Virus, Western Equine - drug effects; Infection; Intestine; Medicinal plants; MTT assay; natural products; NR uptake; Plant extracts; Plant Extracts - chemistry; Plant Extracts - pharmacology; Plaques; Vero Cells; WEEV; Western equine encephalitis; Western equine encephalitis virus
• ISSN: 1478-6419; 1478-6427
• DOI: 10.1080/14786419.2010.490216

Achyrocline satureioides (Asteraceae) is a medicinal plant traditionally used in Argentina for the treatment of intestinal infections and various digestive disorders. Its infusion is widely utilised for respiratory problems and viral infections. The objective of this study was to investigate cytotoxicity, virucidal and antiviral properties of the cold aqueous extract (CAE) and hot aqueous extract (HAE) of this plant against Western equine encephalitis virus (WEEV). Cytotoxicity in Vero cells was evaluated by maximum non-cytotoxic concentration (MNCC), neutral red (NR) uptake and MTT reduction methods. To study the antiviral activity of aqueous extracts, plaque reduction assay was performed after pre-treatment of host cells, adsorption, penetration and post-penetration of the virus. Extracellular virus inactivation was also analysed by the same method. Extracts showed strong inhibitory activity after virus penetration with selective index values of 32 (NR) and 63.3 (MTT) for the CAE, and 16.2 (NR) and 24.3 (MTT) for the HAE. Both extracts exhibited virucidal action with lower efficacy than their antiviral properties. The present results demonstrate that aqueous extracts of A. satureioides are active against WEEV. Further studies are needed in order to identify which compounds could be responsible for this effect, and how they exert antiviral action.