Lectin from red algae Amansia multifida Lamouroux: Extraction, characterization and anti-inflammatory activity.

Seaweed lectins are very promising biotechnological tools that also gain prominence when applied to the pharmacology field. The purpose of the present work was to isolate and characterize lectin from the red algae Amansia multifida and subsequently test it in general inflammation models. The lectin was purified by ion exchange chromatography, characterized with two-dimensional electrophoresis, automated analysis of amino acid sequences and circular dichroism spectroscopy. The pharmacological tests performed were paw edema induced by carrageenan or rapid inflammatory mediators, peritonitis induced by carrageenan and myeloperoxidase leukocyte count assays, glutathione and cytokine concentration. Our results have identified a 30 KDa molecular weight protein that presents a major secondary structure arranged in ß-strand elements (~43%). A fragment of 20 amino acid residues was sequenced and presented low identity to the known classes of lectins from marine alga. This lectin was able to modulate inflammatory parameters such as paw edema, leukocyte migration, oxidative stress and proinflammatory cytokines. Thus, the lectin from the seaweed Amansia multifida has evident anti-inflammatory properties because it acts by reducing the formation of edema by modulating the effect of vascular mediators, migration of neutrophils, proinflammatory cytokines and oxidative stress control.

Lectin obtained from the red seaweed Bryothamnion triquetrum: Secondary structure and anti-inflammatory activity in mice.

Seaweeds are sources of biomolecules with biological activities and pharmacological potential - for example, lectins, a group of proteins that can bind reversibly to carbohydrates or compounds containing them. The aim of this study was to elucidate the structural properties of a lectin extracted from the red seaweed Bryothamnion triquetrum (BtL) and to investigate its anti-inflammatory activity in mice. The lectin was purified by precipitation with ammonium sulfate and ion-exchange chromatography. Its secondary structure and tryptophan (Trp) microenvironment were analyzed by circular dichroism spectroscopy and steady-state fluorescence spectroscopy, respectively. The anti-inflammatory effect was evaluated by means of paw edema induced by carrageenan or dextran, myeloperoxidase activity in paw tissue, and by measurement of leukocyte and neutrophil migration and cytokine quantification in a peritonitis model. The secondary structure of BtL is mostly composed of ß-strands and unordered conformation, and it is quite resistant to extremes of pH and temperature, preserving the exposure of Trp residues under these conditions. In an assessment of biological activities, groups of mice were subjected to pretreatment with BtL before the inflammatory stimulus. BtL had anti-inflammatory effects in the models tested, and hence may be considered a molecule with potential to be used in the pharmaceutical industry.