Analysis of the biological activity of mimetic peptides derived from Enterolobium contortisiliquum seeds on hemostatic parameters and arterial thrombosis

• Grant number: 18/25282-2
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: January 01, 2019
• End date: December 31, 2019
• Field of knowledge: Biological Sciences - Biochemistry - Chemistry of Macromolecules
• Principal Investigator: Maria Luiza Vilela Oliva
• Grantee: Ruben Siedlarczyk Nogueira
• Host Institution: Escola Paulista de Medicina (EPM). Universidade Federal de São Paulo (UNIFESP). Campus São Paulo. São Paulo , SP, Brazil
• Associated research grant: 17/06630-7 - Fragments derived from the structure of protease inhibitors with selectivity for inhibition of mammalian and microorganism enzymes and its role as an anti-inflammatory, antimicrobial, antithrombotic and anti- tumor agent: mechanism of action, AP.TEM

Abstract

Arterial thrombosis is a serious public health problem throughout the world. Therefore, interest of the research for new therapeutic approaches for the treatment of this disease and its understanding is needed. In this work, we will demonstrate that the use of protease inhibitors derived from plant proteins can help in understanding the mechanisms of arterial thrombosis, as well as serve as the basis for the development of new antithrombotic therapies. In this proposition, we intend to study the activity of peptides derived from the Enterolobium contortisiliquum trypsin inhibitor (EcTI) reactive site, a protein that shows interesting inhibitory properties on plasma kallikrein and factor XII activities in mice. The objective of this project is, through the synthesis of peptides derived from the protein sequence and retro-inverses, establish the minimal structure responsible for biological activity. With these peptides, platelet aggregation studies, PT and aPTT will be performed in experimental groups of mice treated with the peptides, compared to the purified protein and with control animals (0.15 M NaCl) in the plasma collected by cardiac puncture with a needle containing 3.8% sodium citrate. Arterial thrombosis will be induced by photochemical model and animals will be separated into groups according to the treatment (Peptide A, B or C, NaCl or EcTI). In addition, the influence of pH and resistance of these peptides to proteolysis will be verified. Finally, intravital microscopy assays will be performed to visualize the motility of important cells in the process.