Study of the antiallergic activity of flavonoids incorporated into liposomes

• Grant number: 09/18459-4
• Support type: Scholarships in Brazil - Scientific Initiation
• Effective date (Start): February 01, 2010
• Effective date (End): January 31, 2011
• Field of knowledge: Physical Sciences and Mathematics - Chemistry
• Principal researcher: Rose Mary Zumstein Georgetto Naal
• Grantee: Renata Zambelli Rodrigues
• Home Institution: Faculdade de Ciências Farmacêuticas de Ribeirão Preto (FCFRP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil

Abstract

Allergic problems as asthma, rhinitis, food allergy and others have been increasing in the last years and submitting the allergic people to a low quality of life or causing the death. For the most people the strategies used to treat the symptoms are inefficient or impracticable which emphasize the necessity to discover new alternatives that can interfere in the immunological responses in a more efficient way. In this context, the natural products perform a fundamental role and have been the target of considerable research of the new therapeutic agents. Some classes of natural compounds are excellent inhibitors of mast cell degranulation. Among these classes, we can distinguish the flavonoid that can be found is several kind of food. However they are very low soluble in water and easily photodegraded, or oxidized, which reduce the absorption in the body and become more difficult the performance of the biological assay. Besides, due its low water solubility, the application of these compounds by intravenous via is impracticable which make viable the studies focused in nanocarriers systems. The incorporation of these natural compounds in liposomal vesicles can soften the mentioned problems and increase the bioavailability and the performance of the biological assay used to discover new alternatives to treat allergic diseases. Mast cells are the immune system cells that perform a central role in allergic diseases. Those cells, stimulated by an antigen, go through exocytose and release chemical mediators of allergic response as beta-hexosaminidase enzyme. The direct assay to quantify this enzyme (Naal et al., 2004. Biosensors and Bioelectronics 20, 790-795) can be used as a cellular biosensor to monitor the potentiality of drugs to block the mast cell activation and degranulation. In this way, this study intend to prepare and characterize the liposomes containing flavonoids and use the mast cell based biosensor to investigate and compare the antiallergic activity of the flavonoids free and incorporates inside the liposomes.