29 / 2024-10-12 19:22:51

Lactobacillus rhamnosus CIQ249 antagonizes enteropathogenic bacteria infection through regulating intestinal homeostasis: A promising microecological agent candidate

Lactobacillus rhamnosus (L. rhamnosus) has been applied in food and beverage industry for a long history and is recognized as a key probiotic strain with immunomodulatory effects against bacterial infections. However, the mechanisms by which L. rhamnosus protects against enteric pathogens are not fully understood. In this study, we explored the potential mechanisms of L. rhamnosus isolate CIQ249 in regulating intestinal homeostasis as a microecological agent. Our findings revealed that metabolites produced by L. rhamnosus CIQ249 significantly inhibited the growth of enteropathogenic bacteria and effectively alleviated intestinal mucosal injury in chickens infected with pathogenic bacteria. Additionally, treatment with L. rhamnosus CIQ249 enhanced the expression of tight junction proteins ZO-1 and Claudin-1, thus maintaining the integrity of intestinal epithelial tight junctions. Moreover, oral administration of L. rhamnosus CIQ249 significantly promoted the production of immune-related cytokines, enhanced the differentiation of CXCR5+CD4+T lymphocytes, and boosted the proliferation and differentiation of B lymphocytes into IgA-secreting plasma cells. RNA sequencing analysis revealed significant changes in the expression of genes associated with anti-infection immunity. Furthermore, L. rhamnosus strain CIQ249 displayed strong colonization ability in intestine and had a number of well-established benefits. Conclusively, L. rhamnosus was able to enhance both intestinal physical barriers and immune defenses against enteropathogenic bacterial infections, highlighting strain CIQ249 as a promising candidate for the development of microecological agents.