Lycium barbarum polysaccharides improve gut microbiota composition and alleviate pulmonary inflammatory damage in allergic asthma mice by inhibiting the IL-15RA/FUT2 pathway

This study examined the effects of Lycium barbarum polysaccharide (LBP) on the intestinal flora of mice with allergic asthma and its molecular mechanism on lung injury and inflammation. Bioinformatics analysis examined LBP targets for allergic asthma and the gut microbial ecosystem. IL-13 was used to create an in vitro cell model of allergic asthma in lung epithelial cell LA-4 and ovalbumin (OVA)-sensitized mice. LBP effects on inflammatory cell infiltration, mucus formation, proinflammatory factor release, and pulmonary epithelial fucosylation were examined after loss- and gain-function experiments. LBP therapy altered fecal microbial populations, decreased IL-15RA and FUT2 expression, and reduced pulmonary epithelial fucosylation in asthmatic mice. IL-15RA or FUT2 knockdown mimicked LBPs in asthmatic mice. More notably, LBPs or IL-15RA/FUT2 knockdown reduced pulmonary epithelial cell fucosylation. LBP reduces lung injury and inflammation in mice with allergic asthma by downregulating the IL-15RA/FUT2 pathway, inhibiting pulmonary epithelial fucosylation, and increasing anti-inflammatory intestinal flora.