Angelica gigas polysaccharide induces CR3-mediated macrophage activation and the cytotoxicity of natural killer cells against HCT-116 cells via NF-KB and MAPK signaling pathways

Angelica gigas ( A. gigas ) is traditional medicinal herb that mainly exists in Korea and northeastern China. There have been relatively few studies conducted thus far on its polysaccharides and their bioactivities. We purified and described a novel water-soluble polysaccharide derived from A. gigas and investigated its immunoenhancing properties. The basic components of crude and purified polysaccharides (F1 and F2) were total sugar (41.07%70.55%), protein (1.12-10.33%), sulfate (2.9-5.5%), and uronic acids (0.5-31.05%) in total content. Our results demonstrated that the crude and fractions' molecular weights ( M w ) varied from 42.2 to 285.2 x 10 3 g/mol. As the most effective polysaccharide, F2 significantly stimulated RAW264.7 cells to release nitric oxide (NO) and express several cytokines. Furthermore, F2 increased the expression of tumor necrosis factor-alpha (TNF-alpha), interferon -gamma (IFN- gamma), natural killer cytotoxicity receptors (NKp44), and granzyme-B in NK-92 cells and enhanced the cytotoxicity against HCT-116 cells. In our experiments, we found that F2 stimulated RAW264.7 cells and NK-92 cells via MAPK and NF - K B pathways. The monosaccharide and methylation analysis of the high immunostimulant F2 polysaccharide findings revealed that the polysaccharide was primarily composed of 1 -> 4, 1 -> 6, 1 -> 3, 6, 1 -> 3 and 1 -> 3, 4, 6 galactopyranose residues, 1 -> 3 arabinofuranose residues, 1 -> 4 glucopyranose residues. These results demonstrated that the F2 polysaccharide of A. gigas which possesses potential immunostimulatory attributes, could be used to create a novel functional food.