Chemical structure and anti-inflammatory effect of polysaccharides obtained from infusion of Sedum dendroideum leaves.

Sedum dendroideum is popularly known as balsam and used for treatment of inflammatory disorders. Two polysaccharides (RSBAL-H2O and RSBAL-0.5) were isolated from infusion of its dried leaves, using dialysis at 100kDa cut-off membrane and anion exchange chromatography. Methylation and NMR analyses showed that RSBAL-H2O is a highly methyl-esterified homogalacturonan, constituted by (1→4)-α-D-GalA residues, whereas RSBAL-0.5 is a highly methyl-esterified homogalacturonan branched at O-3, probably by type II arabinogalactans and arabinans. In this study we showed that these balsam polysaccharides stimulate secretion of the cytokines TNF-α, IL-1β and IL-10 by THP-1 macrophages, acting as immunostimulatory agents. But, on the other hand, they reduce TNF-α and IL1-β secretion induced by a pro-inflammatory agent (LPS), showing anti-inflammatory effect.