Suppressive effect of pectic polysaccharides extracted from Rauwolfia verticillata(Lour.) Baill.var.hainanensis Tsiang on inflammation by regulation of NF-κB pathway and interleukin-17 in mice with dextran sulphatesodium-induced ulcerative colitis

Objective:To investigate the effects of pectic polysaccharides extracted from Rauwolfia verticillata(Lour.) Baill.var.hainanensis Tsiang on an experimental murine colitis model.Methods:Experimental colitis was induced by dextran sulfate sodium(DSS),and mice were divided into 4 groups:control.DSS alone.DSS plus SASP,DSS plus pectic polysaccharides.The disease activity index(DAI) and histological score were observed.The tumor necrosis factor(TNF)-α and interleukin(IL)-17 levels were measured by enzyme-linked immunosorbent assay.I κ B and NF-κB p65 expression were assessed by western blot analysis.Myeloperoxidase(MPO) activity was determined by using MPO assay kit.Re.sults:Administration of pectic polysaccharides significantly reduced the severity of DSS-induced colitis as assessed by DAT and histological score,and resulted in down regulation of MPO activity and NF-κB p65 expression and subsequent degradation of IκB protein,strikingly reduced the production of TNF-α and IL-17.Conclusions:Pectic polysaccharides extracted from Rauvolfia verticillata(Lour.)Baill.var.hainanensis Tsiang exerts beneficial effects in experimental colitis and may therefore provide a useful therapeutic approach for the treatment of UC.