Multi-Strain Probiotics Alleviate Food Allergy-Induced Neurobehavioral Abnormalities by Regulating Gut Microbiota and Metabolites

<b>Background and aim:</b> Neurobehavioral changes associated with food allergies have been reported, but the therapeutic effects of probiotics have not been fully explored. Our study aimed to investigate the impact of multi-strain probiotics on neurobehavioral outcomes and to elucidate the underlying mechanism via the microbiota-gut-brain axis. <b>Methods:</b> C57BL/6J Male mice were randomly divided into the following three groups: (1) control group; (2) OVA-sensitized group; (3) OVA-sensitized group treated with multi-strain probiotics (OVA + P). Anaphylactic reactions and behavioral abnormalities were assessed by histological, immunological, and behavioral analyses. To further elucidate the underlying mechanisms, the prefrontal cortex was collected for microglial morphological analysis, while serum and fecal samples were obtained for untargeted metabolomic profiling and 16S rDNA-based gut microbiota analysis, respectively. <b>Results:</b> Multi-strain probiotics significantly alleviated anaphylactic reactions in OVA-sensitized mice, as evidenced by reduced serum IgE levels, decreased Th2 cytokines, and reduced epithelial damage. Meanwhile, neurobehavioral symptoms were alleviated, including anxiety-like and depression-like behaviors, repetitive behaviors, social avoidance, and impaired attention. Mechanistically, probiotics administration suppressed production of inflammatory cytokines (TNF-α, IL-1β and IL-6) and inhibited activation of M1 microglia in the prefrontal cortex, which might contribute to neuron recovery. Furthermore, multi-omics analysis revealed that amino acid metabolism restoration in OVA + P mice, particularly carboxylic acids and derivatives, which was remarkably correlated with alterations in gut microbiota and behaviors related to FA. <b>Conclusions:</b> Gut microbiota and its amino acid metabolites mediate the therapeutic effects of multi-strain probiotics on FA-induced behavioral abnormalities. These effects occur alongside the suppression of neuroinflammation and microglial activation in the prefrontal cortex. Our findings highlight the neuroimmune regulatory role of the gut-microbiota-brain axis and support the potential use of probiotics as an intervention for FA-induced brain dysfunctions.