Selenium-enriched Lactobacillus coryniformis H8 alleviates LPS-induced jejunal injury in chicks by modulating antioxidant activity, inflammation, selenoprotein genes, and gut microbiota.

Intestinal inflammation in chicks remains a prevalent health concern, highlighting the importance of developing effective alternatives to conventional antibiotics. This study aimed to investigate the effect of selenium-enriched Lactobacillus coryniformis H8 (Se-H8) in alleviating lipopolysaccharides (LPS)-induced intestinal inflammation in chicks and the related mechanisms. 252 1-day-old White Leghorn chicks (n = 6 cages/treatment, 6 chicks/cage) were randomly divided into seven groups (Control, LPS, H8, Se-H8, H8-Na(2)SeO(3), Na(2)SeO(3), and ENR). After 14 days of continuous gavage, a 3-day LPS intraperitoneal stress injection was performed. Serum, jejunum, and cecal faeces were collected for analysis of selenium levels, inflammatory factors, antioxidant status, gene expression, and microbial composition. Compared to the other treatment groups, Se-H8 exhibited the most pronounced alleviation of LPS-induced intestinal damage. This superior efficacy was reflected in significantly improved jejunal morphology, elevated serum selenium levels (P < 0.05), enhanced antioxidant capacity (increased GPX and SOD activities, decreased MDA levels; P < 0.05), and modulated inflammatory responses (reduced IL-1β and TNF-α, increased IL-10; P < 0.05). Furthermore, Se-H8 altered the expression of 23 selenoprotein genes in the jejunum and suppressed mRNA expression of key genes (TLR4, MyD88, NF-κB, IL-1β, TNF-α, and IL-10) in the TLR4/MyD88/NF-κB signaling pathway compared to the LPS group. Additionally, cecal microbiological analyses showed that Se-H8 increased the abundance of seven beneficial microorganisms, including Eubacterium_oxidoreducens_group, Eisenbergiella, Enorma, Catenibacillus, Merdibacter, Lachnospiraceae_FCS020_group, and GCA-900066575. In conclusion, Se-H8 alleviates LPS-induced jejunal injury by regulating antioxidant status, inflammation levels, selenoprotein genes expression, and gut microbial homeostasis. These findings highlight the potential of selenium-enriched microorganisms like Se-H8 as viable antibiotic alternatives for managing enteritis in poultry.