Polysaccharides from Smilax glabra inhibit the pro-inflammatory mediators via ERK1/2 and JNK pathways in LPS-induced RAW264.7 cells

The rhizomes of Smilax glabra have been used as both food and folk medicine in many countries for a long time. However, little research has been reported on polysaccharides of S. glabra. In the present study, two polysaccharide fractions, SGP-1 and SGP-2, were isolated from the rhizomes of S. glabra with the number average molecular weights of 1.72 x 10(2) kDa and 1.31 x 10(2) kDa, and the weight average molecular weights of 131 x 10(5) kDa and 1.18 x 10(5) kDa, respectively, and their mainly monosaccharide compositions were both galactose and rhamnose (2.5:1). Both SGP-1 and SGP-2 significantly suppressed the release of nitric oxide (NO), tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) from LPS-induced RAW 264.7 cells, as well as the mRNA expression of inducible nitric oxide synthase (iNOS),TNF-alpha and IL-6. Additionally, SGP-1 and SGP-2 repressed the extracellular signal-regulated kinase (ERK) and c-Jun NH2-terminal kinase (JNK). These findings strongly suggested polysaccharides were also the anti-inflammatory active ingredient for S. glabra, and the potential of SGP-1 and SGP-2 as the anti-inflammatory agents. (C) 2015 Published by Elsevier Ltd.