Probiotics‐Loaded Selenium Nanoparticles Effectively Alleviated DSS‐Induced Colitis by Scavenging ROS and Remodeling Intestinal Innate Immune and Microbiota

Abstract Alterations in the intestinal microenvironment, including increased levels of reactive oxygen species (ROS), abnormalities in intestinal mucosal immune regulation, and dysbiosis of the intestinal microbiota, are crucial to the development of inflammatory bowel disease (IBD). Herein, an oral colon‐targeting Se‐Probiotic@Alginate bead (BLSe) with ROS‐scavenging ability and gut immune‐microbiota microenvironment remodeling ability is developed using alginate as the primary outer shell encapsulated with probiotics Bacillus licheniformis (BL) and selenium nanoparticles stabilized by yeast glucan (SeNPs). In vitro studies have shown that SeNPs possess antioxidant activity and BLSe exhibits excellent stability in gastric fluids and are released in intestinal fluids. In vivo studies have also shown that BLSe significantly alleviated dextran sulphate sodium (DSS)‐induced colitis in mice by inhibiting colon shortening, enhancing antioxidant activity, reducing pro‐inflammatory cytokine secretion, and protecting the intestinal mucosal barrier. 16S ribosomal RNA sequencing shows that BLSe can remodel the composition of the gut microbiota by improving bacterial diversity and restoring the relative abundance of beneficial bacteria in the colon. Overall, this study advances a promising probiotic‐based nanomedicine for managing IBD.