Characterization and biological effects of two polysaccharides isolated from Acanthopanax sciadophylloides

• Two polysaccharides, ANP and AAP, were isolated from Acanthopanax sciadophylloides.
• ANP showed anti-herpetic effect in vitro, whereas AAP showed anti-herpetic activity in vivo.
• Both polysaccharides showed immunomodulatory effects on RAW 264.7 cells.

Two polysaccharides abbreviated ANP and AAP were isolated from the young buds of Acanthopanax sciadophylloides. ANP consisted of l-arabinose, d-mannose, d-glucose and d-galactose in a ratio of ca 1.0:2.6:2.5:1.4 and its weight average molecular weight (Mw) was 1.07 × 104. AAP consisted of l-arabinose, d-galactose and 4-O-methyl-d-glucuronic acid in a ratio of ca 5:10:1, and its Mw was estimated to be 8.40 × 104. ANP was suggested to be an acetylated heteropolysaccharide, whereas AAP was speculated to be a type II arabinogalactan on the basis of structural analysis data. Both polysaccharides were found to stimulate NO production and induce the expression of cytokine mRNAs including IL-1β, IL-6, IL-10 and TNF-α on RAW264.7 cells. They also induced NF-κB activation in RAW-Blue cells. NO production and NF-κB activation by both polysaccharides were decreased by pretreatment with neutralizing anti-TLR-4 and anti-CD14 antibodies but not with anti-TLR-2, anti-SR-A, anti-CD11c, and anti-Dectin-1 antibodies. Therefore, these immunostimulating effects of ANP and AAP were suggested to be promoted by the interaction through the membrane receptors, TLR-4 and CD14. In addition to immunomodulating effects, ANP showed anti-HSV-2 effects in vitro.