Study of the antiallergic potential of extracts from Amazon Forest

• Grant number: 11/18249-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: November 01, 2011
• End date: June 30, 2013
• Field of knowledge: Physical Sciences and Mathematics - Chemistry
• Principal Investigator: Rose Mary Zumstein Georgetto Naal
• Grantee: Marcela Barros Motta
• Host Institution: Faculdade de Ciências Farmacêuticas de Ribeirão Preto (FCFRP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil

Abstract

Mast cells are immune system cells that play a central role in allergic diseases. These cells, when stimulated by an antigen, experience a cascade of biochemical reactions which culminate in exocytosis and release of chemical mediators of allergic response, including histamine, serotonin, and the beta-hexosaminidase enzyme. The test for the direct quantification of beta-hexosaminidase, based on RBL-2H3 mast cells line, was recently developed for application as biosensors in the study of bioactive molecules with therapeutical potential. Many substances have relevant biological activities, but can not be used as new drugs since they cause allergic reactions. The advantage of the biological test for the beta-hexosaminidase proposed for this study is on the fact that it signals both inhibition and stimulation of allergies by the investigated substance. In addition to the cascade of intracellular reactions, mentioned above, other processes such as an increase of endosomal pH and release of reactive oxygen species (ROS) occur, concomitantly, and participate in the degranulation. This last event roused our attention to the extracts from plants of the Amazon Rainforest such as species named Byrsonima crassifolia L. (Malpighiaceae), Inga edulis L. (Leguminosae), Euterpe oleracea (Arecaceae), Bixa orellana (Bixaceae) and Dalbergia monetaria L. (Leguminosae), which are used by the population of the Amazon in the treatment of several diseases and showed strong antioxidant activity, crucial in the inhibition of ROS. These extracts are rich in polyphenolic compounds, such as flavonoids, known to possess broad biological activities including antiallergic activity. Thus, the goal of this work is to evaluate the antiallergic potential of such extracts and contribute to the discovery of new structures or new alternatives that can alleviate the symptoms caused by allergic reactions. The extracts that show a potential inhibitor will be investigated, also, as the ability to inhibit the production of ROS and cytotoxicity.(AU)