RESUMO
Sulfated polysaccharides extracted from seaweed have important pharmacological properties. Thus, the aim of this study was to characterize the sulfated polysaccharide (PLS) from the algae Hypnea musciformis and evaluate its protective effect in colitis induced by trinitrobenzene sulfonic acid in rats. The sulfated polysaccharide possess a high molecular mass (1.24×10(5)gmol(-1)) and is composed of a κ-carrageenan, as depicted by FT-IR and NMR spectroscopic data. PLS was administered orally (10, 30, and 60mg/kg, p.o.) for three days, starting before TNBS (trinitrobenzene sulfonic acid) instillation (day 1). The rats were killed on day three, the portion of distal colon (5cm) was excised and evaluated macroscopic scores and wet weight. Then, samples of the intestinal were used for histological evaluation and quantification of glutathione, malonyldialdehyde acid, myeloperoxidase, nitrate/nitrite and cytokines. Our results demonstrate that PLS reduced the colitis and all analyzed biochemical parameters. Thus, we concluded that the PLS extracted from the marine algae H. musciformis reduced the colitis in animal model and may have an important promising application in the inflammatory bowel diseases.
Assuntos
Galactanos/química , Galactanos/farmacologia , Intestinos/efeitos dos fármacos , Sulfatos/química , Ácido Trinitrobenzenossulfônico/efeitos adversos , Animais , Citocinas/metabolismo , Citoproteção/efeitos dos fármacos , Galactanos/isolamento & purificação , Mucosa Intestinal/metabolismo , Intestinos/citologia , Intestinos/imunologia , Masculino , Infiltração de Neutrófilos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos WistarRESUMO
Seaweeds are considered an important source of bioactive molecules. In this work the marine red alga Gracilaria caudata was submitted to aqueous extraction of their polysaccharides for 2 h at 100 °C. The polysaccharide fraction (PGC) presented a recovery of 32.8%. The sulfate content of PGC, calculated by S%, is 1 ± 0.2% and the degree of sulfation accounts for 0.13 ± 0.2. High-Performance Size-Exclusion Chromatography demonstrated that PGC consists of a high molecular weight polysaccharide (2.5 × 10(5)gmol(-1)). Chemical analysis of PGC was performed by microanalysis, infrared (FT-IR) and nuclear magnetic resonance (NMR, 1 and 2D) spectroscopy. The structure of PGC is mainly constituted by the alternating residues 3-linked-ß-D-galactopyranose and 4-linked-3,6-α-L-anhydrogalactose; however some hydroxyl groups were substituted by methyl groups and pyruvic acid acetal. The biological precursor of 3,6-α-L-anhydrogalactose (6-sulfate-α-l-galactose) was also detected.