RESUMO
Cells use glycans to encode information that modulates processes ranging from cell-cell recognition to programmed cell death. This information is encoded within a glycocode, and its decoding is performed by carbohydrate-binding proteins. Among these, lectins stand out due to their specific and reversible interaction with carbohydrates. Changes in glycosylation patterns are observed in several pathologies, including cancer, where abnormal glycans are found on the surfaces of affected tissues. Given the importance of the bioprospection of promising biomolecules, the current work aimed to determine the structural properties and anticancer potential of the mannose-specific lectin from seeds of Canavalia villosa (Cvill). Experimental elucidation of the primary and 3D structures of the lectin, along with glycan array and molecular docking, facilitated the determination of its fine carbohydrate-binding specificity. These structural insights, coupled with the lectin's specificity, have been combined to explain the antiproliferative effect of Cvill against cancer cell lines. This effect is dependent on the carbohydrate-binding activity of Cvill and its uptake in the cells, with concomitant activation of autophagic and apoptotic pathways.
Assuntos
Canavalia , Lectinas , Lectinas/farmacologia , Lectinas/análise , Canavalia/metabolismo , Simulação de Acoplamento Molecular , Lectinas de Plantas/metabolismo , Sementes/metabolismo , Carboidratos/análise , Polissacarídeos/análiseRESUMO
In this study, the effect of lecithin (LEC) on the crystallization and gelation of fruit wax (FW) with sunflower oil was researched. A synergistic effect on the gel strength was observed at FW : LEC ratios of 75 : 25 and 50 : 50, compared to the corresponding single component formulations (100 : 0 and 0 : 100). Even below the critical gelling concentration (Cg) of FW, the addition of lecithin enabled gel formation. Lecithin affected the thermal behavior of the structure by delaying both crystallization and gel formation. The phospholipid acted as a crystal habit modifier changing the microstructure of the oleogel, as was observed by polarized light microscopy. Cryo-scanning electron microscopy revealed a similar platelet-like arrangement for both FW as a single oleogelator and FW in combination with LEC. However, a denser structure could be observed in the FW : LEC oleogelator mixture. Both the oil-binding capacity and the thixotropic recovery were enhanced upon lecithin addition. These improvements were attributed to the hydrogen bonding between FW and LEC, as suggested by Raman spectroscopy. We hypothesized that lecithin alters the molecular assembly properties of the FW due to the interactions between the polar moieties of the oleogelators, which consequently impacts the hydrophobic tail (re)arrangement in gelator-gelator and solvent-gelator interactions. The lipid crystal engineering approach followed here offered prospects of obtaining harder self-standing structures at a lower oleogelator concentration. These synergistic interactions provide an opportunity to reduce the wax concentration and, as such, the waxy mouthfeel without compromising the oleogel properties.