Abstract:Objective This study aims to explore the alleviating effect of a probiotic formula on H1N1 infection in mice and the effects of this formula on the gut microbiota and metabolites.Method Lactobacillus rhamnosus CCFM1279 with the ability to alleviate respiratory tract infections was combined with Limosilactobacillus reuteri CCFM1145, Lacticaseibacillus casei CCFM1127, and various dietary factors to prepare a probiotic formula. SPF-grade ICR mice of 3 to 4 weeks old were randomized into blank, model, positive control (oseltamivir), and probiotic formula groups. A mouse model of influenza was constructed by nasal inhalation with the H1N1 virus. The alleviating effect of the probiotic formula on H1N1 infection was evaluated based on indicators such as body mass change rate, virus load, and L-lactate dehydrogenase activity in the bronchoalveolar lavage fluid. The 16S rRNA gene sequencing was employed to evaluate changes in the gut microbiota. Non-targeted metabolomics was employed to analyze changes in gut metabolites.Result Oral administration of the probiotic formula effectively resisted H1N1 influenza by inhibiting virus replication, alleviating lung inflammation and damage, and reducing the L-lactate dehydrogenase activity in the bronchoalveolar lavage fluid. In addition, the probiotic formula regulated the mass concentrations of IL-6 and TNF-α in the host serum and the relative expression level of the antiviral protein OAS1 in the lung tissue. It significantly increased the abundance of Parabacteroids. Metabolite analysis showed that the probiotic formula significantly increased the relative abundance of metabolites such as pyruvic acid.Conclusion Oral administration of the probiotic formula can effectively resist the H1N1 virus in the mouse model of H1N1 infection. The probiotic formula may play a role in alleviating influenza progression by specifically regulating the gut microbiota and metabolites. The findings provide new research ideas for the prevention and treatment of influenza via the gut microbiota.
