Análise estrutural de uma lectina de sementes de Diocle lasiophylla Mart. ex Benth e avaliação do seu efeito vasorelaxante, inflamatório e nociceptivo

Abstract

Lectins are (glyco)proteins of non-immune origin, capable of reversibly binding to specific mono or oligosaccharides, via a non-catalytic domain. The legume family is the most well-studied group, with many lectins purified, structurally characterized and applied in biological and biotechnological activities. The subtribe Diocleinae presents lectins that have high structural similarity, but different effects on biological activity assays. This variability is due to small differences which may be analyzed by structural studies. In context, this study aims to structurally characterize and analyze the effect on contractility, inflammation and nociception studies, of a lectin present in Dioclea lasiophylla Mart. ex Benth seeds, species of the Leguminosae family, Papilionoideae subfamily, Phaseoleae tribe, Diocleinae subtribe. The lectin (DlyL) was purified in a single step by affinity chromatography on Sephadex G-50 matrix. The primary sequence of DlyL was determined by tandem mass spectrometry (MS/MS) and sequencing of the gene encoding to the lectin, showing high similarity with others lectins from species of the same genus. The three-dimensional structure of DlyL complexed with X-Man was predicted in silico by homology modelling. DlyL presented vasorelaxant effect on smooth muscle of rat’s endothelialized aortas as well as inflammatory activity in the rat paw edema model. The lectin presented hipernociceptive effect associated with inflammation, determined by Von Frey method.