Selenium nanoparticle-modified probiotics attenuate deoxynivalenol-induced intestinal injury in chickens via glutathione-mediated metabolic pathway.

Deoxynivalenol (DON), one of the most prevalent mycotoxins, primarily targets the intestine causing oxidative stress and inflammatory storm. Meanwhile, Selenium nanoparticles (SeNPs) have been demonstrated to possess multiple physiological functions, including anti-inflammatory and antioxidant activities. We successfully synthesized biogenic SeNPs with zero-valent and 142 ± 23.5 nm particle size using the intrinsic oxidoreductase enzymes and metabolic machinery of Lactobacillus rhamnosus CICC 20257 (Lr) to efficiently reduce sodium selenite through a biological process. This study intends to investigate the protective mechanism by which Lr-SeNPs alleviates DON-induced intestinal damage in chickens. Fifteen Hy-Line Variety Brown roosters were randomly divided into three groups: Control, DON (2.5 mg/kg), and DON (2.5 mg/kg) + Lr-SeNPs (0.5 mg Se/kg). The results showed that Lr-SeNPs exhibited excellent safety and antioxidant activity, and effectively attenuated DON-induced intestinal oxidative stress, inflammatory responses, and epithelial hyperpermeability. In addition, 16S rRNA sequencing and untargeted metabolomics revealed that Lr-SeNPs modulated microbial diversity, promoted the enrichment of beneficial bacteria such as Faecalibacterium, Agathobaculum, and Prevotellaceae, and reduced the abundance of Helicobacter. Furthermore, Lr-SeNPs enhanced the production of metabolites including glutamine, L-glutamic acid, and taurine. Integrative multi-omics analysis identified the glutathione metabolic pathway as a candidate mechanism, and subsequent L-BSO inhibition experiments confirmed the involvement in the protective effect of Lr‑SeNPs. These findings provide a theoretical basis for the application of Lr-SeNPs in modulating gut microbiota and metabolism, as well as its potential application in poultry nutrition and health.