Stimulation-responsive mucoadhesive probiotics for inflammatory bowel disease treatment by scavenging reactive oxygen species and regulating gut microbiota.

Inflammatory bowel disease (IBD) is characterized by the high level of reactive oxygen species (ROS) and highly dysfunctional intestinal flora. Here, a stimulation-responsive mucoadhesive probiotic Lac@HDP was rationally constructed for achieving specific adhesion of colitis site and depleting high level of ROS in inflammatory site. Briefly, Lac is Lactobacillus acidophilus, HDP is obtained by hyaluronic acid grafted with dopamine protected by phenylboric acid. Specifically, by consuming a large amount of ROS, phenyl borate group of Lac@HDP is oxidized and fractured, thus exposing the catechol hydroxyl group and obtaining strong mucosal adhesion ability, thereby significantly prolong the retention time of Lac in the inflammatory site. In the murine model of acute and chronic colitis, the stimulation-responsive mucoadhesive probiotics were significantly more effective in alleviating colitis symptoms than antioxidants and probiotics alone. In addition, the abundance and diversity of intestinal flora were increased after treatment with Lac@HDP, which was helpful to alleviate IBD. Importantly, the stimulation-responsive mucoadhesive probiotics have good biological safety in vivo, which provides the prospect of clinical application in the future.