" In vitro screening of extracts from Cerrado plants rich in flavonoids against the Chikungunya virus."
Cerrado plants, plant extract, flavonoids, antiviral, chikungunya.
Chikungunya virus (CHIKV) is a reemerging arbovirus of the Togaviridae family that causes debilitating musculoskeletal disorders in humans, characterized by fever, polyarthralgia and myalgia. There is no vaccine or treatment for people infected with CHIKV to date, highlighting the importance of deepening the knowledge about CHIKV host cell interactions and viral replication strategies. The synthetic compounds studied so far have little effect on CHIKV infection, and have strong side effects, limiting their usefulness. For this reason, the use of plant-based compounds that affect the replication cycles of these viruses has been proposed as a promising strategy. The aim of the present study is to evaluate the potential of aqueous extracts, rich in flavonoids, from the leaves of Eugenia dysenterica DC (ED), Erythroxylum suberosum (ES), Miconia chamissois Naudin (MC), Morus nigra Linné (MN) and Sapindus saponaria L (SS), at different stages of the CHIKV replication cycle, using in vitro analyses. The cytotoxicity profiles of the extracts were obtained through lysosomal viability using the neutral red incorporation assay, and the antiviral potential was determined by plaque assay in the post-, co- and pre-treatment steps. In vitro assays revealed that 100 µg/mL of ED extract reduced the number of lysis plaques by 87 and 85% in post- and pre-treatment stages, respectively. However, 60 µg/mL of ES extract reduced the number of plaques by 85% in the post-treatment step. In the co-treatment step, ES reduced by 100% the number of plaques formed at a concentration of 40 µg/mL. The findings described here indicate that ED and ES extracts, or their secondary metabolites, are a potential source of new antiviral compounds and can be used for the development of new anti-CHIKV drugs.