Pleurotus citrinopileatus polysaccharides ameliorate DSS-induced ulcerative colitis by improving intestinal barrier and inflammation modulation via NF-κB pathway.

The aim was to investigate the pharmacological effects of a polysaccharide isolated from Pleurotus citrinopileatus on ulcerative colitis (UC). One polysaccharide, CP-2-2, was isolated and purified from P. citrinopileatus body fruit using chromatographic methods. CP-2-2 consisted of Fuc, Ara, Gal, Man, and Fru, with molar ratios of 1.38 %, 7.54 %, 84.49 %, 5.86 %, and 0.73 %, respectively, with Mw of 32.5 kDa, and its FITR and methylation were analyzed. In dextran sulfate sodium(DSS)-induced UC mice, CP-2-2 significantly alleviated UC injuries including decreasing body weight loss and disease activity index (DAI), and increasing colon length. We also found CP-2-2 significantly inhibited the production of inflammatory cytokines. Immunofluorescence staining and western blotting results showed CP-2-2 might regulate inflammation, partly through the NF-κB pathway. Furthermore, CP-2-2 treatment significantly ameliorated intestinal pathological damage and improved the intestinal barrier. In the in vitro experiments, we found that CP-2-2 was involved in the inhibition of apoptosis and ferroptosis. Our results revealed the protective effects of CP-2-2 against DSS-induced colitis could be partly attributed to its inhibitory role in NF-κB signaling and its protective effects on intestinal epithelial cells, suggesting CP-2-2 might be a potential functional agent.