Structural characterization of the polysaccharides from Atractylodes chinensis (DC.) Koidz. and the protective effection against alcohol-induced intestinal injury in rats.

A neutral polysaccharide, AP, with a weight-average molecular weight of 60.61 kDa, consisting mainly of arabinose and galactose, was isolated from the rhizomes of Atractylodes chinensis (DC.) Koidz. Methylation analyses and nuclear magnetic resonance spectroscopy indicated that the probable repeat unit of AP was →3,6)-α-D-Galp-(1→ residues and constituted the main chain, with a side chain of →5)-α-L-Araf-(1→ and terminal α-L-Araf attached to C-6 of the main chain. The protective activity and potential mechanisms of action of AP on the intestinal tract were investigated. AP improved intestinal oxidative stress injury and inflammatory responses by promoting the nuclear factor erythroid 2-related factor 2/heme oxygenase-1 signaling pathway and inhibiting the toll-like receptor 4/myeloid differentiation primary response protein 88/nuclear factor-kappa B signaling pathway, but also repaired colonic mucosal injury and reduced intestinal leakage of endotoxins by promoting expression of the tight-junction proteins zonula occludens-1 and occludin. AP improved ecological dysregulation of the intestinal microbiota and promoted the growth of the potentially beneficial bacteria Lactobacillus_taiwanensis, Limosilactobacillus_reuteri and Akkermansia_muciniphila. AP promoted intestinal health by increasing the production of potentially beneficial metabolites such as short-chain fatty acids, Indole-3-propionic acid, and N-Eicosapentaenoyl tryptophan through metabolism (amino acids, lipids, carbohydrates). These results suggest that AP is a promising prebiotic in attenuating alcohol-induced intestinal damage.