Evaluation of anti-dengue activity of products derived from Brazilian native species: Baccharis dracunculifolia, Dalbergia ecastophyllum, and Agaricus subrufescens (=Agaricus brasiliensis)

• Grant number: 14/17007-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: November 01, 2014
• End date: March 31, 2016
• Field of knowledge: Biological Sciences - Microbiology
• Principal Investigator: Francielle Tramontini Gomes de Sousa
• Grantee: Larissa Vieira Bio
• Host Institution: Instituto de Medicina Tropical de São Paulo (IMT). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

Dengue is an infectious disease which causes annual death of more than 22 thousand people around the world.There is no vaccine or specific medicine available to treat this significant public health problem so far. Baccharis dracunculifolia is the main botanical source of green propolis and presents important demonstrated pharmacological activities, including antiviral action. Dalbergia ecastophyllum originates the red propolis, with insufficiently studied biological properties and chemical composition different from the green propolis. Agaricus brasiliensis is a basidiomycete fungus native to Brazil widely consumed and studied due its therapeutic properties, most of them related to its polysaccharidic content, specially (1,6)-(1,3)-beta-D-glucans. Given the importance of natural products as a source of molecules applied on the research and development of new drugs and the great Brazilian biodiversity, this work aims to evaluate the anti-dengue activity of plant ethanolic extracts of Baccharis dracunculifolia and Dalbergia ecastophyllum, as well as of the (1,6)-(1,3)-beta-D-glucan isolated from Agaricus brasiliensis fungus. The cytotoxicity will be analyzed in vitro by the MTT method. The anti-dengue activity (DENV-2, American/Asian genotype) will be firstly tested in pre- and post-infections steps through plaque reduction assay. Samples with promising results will be selected to perform mechanistic studies using different methodological approaches. Furthermore, in the present project, the potential of samples to treat vascular leakage caused by dengue will be evaluated in an in vitro co-culture system of monocytes and endothelial cells, which is available in the Laboratory of Virology - Instituto de Medicina Tropical. The obtained data will contribute to the development of new therapeutic strategies to prevent and/or treat dengue infections, promoting the sustainable use of native species and the strengthening of applied research in partnership with different Universities, contributing to scientific and technological development of the country.