Mannose coated selenium nanoparticles normalize intestinal homeostasis in mice and mitigate colitis by inhibiting NF-κB activation and enhancing glutathione peroxidase expression

Impaired intestinal homeostasis is a major pathological feature of inflammatory bowel diseases (IBD). Mannose and selenium (Se) both demonstrate potential anti-inflammatory and anti-oxidative properties. However, most lectin receptors bind free monosaccharide ligands with relatively low affinity and most Se species induce side effects beyond a very narrow range of dosage. This has contributed to a poorly explored therapies for IBD that combine mannose and Se to target intestinal epithelial cells (IECs) for normalization gut homeostasis. Herein, a facile and safe strategy for ulcerative colitis (UC) treatment was developed using optimized, mannose-functionalized Se nanoparticles (M-SeNPs) encapsulated within a colon-targeted hydrogel delivery system containing alginate (SA) and chitosan (CS). This biocompatible nanosystem was efficiently taken up by IECs and led to increased expression of Se-dependent glutathione peroxidases (GPXs), thereby modulating IECs' immune response. Using a mouse model of DSS-induced colitis, (CS/SA)-embedding M-SeNPs (C/S-MSe) were found to mitigate oxidative stress and inflammation through the inhibition of the NF-kB pathway in the colon. This stabilized mucosal homeostasis of IECs and ameliorated colitis-related symptoms, thereby providing a potential new approach for treatment of IBD.