Hyperuricemia (HUA), a metabolic disorder characterized by elevated serum uric acid resulting from imbalanced production and excretion, is associated with gout and other serious health issues. This study aimed to screen out the potential probiotics with HUA-alleviating properties among 20 Lactobacillus strains. The results showed that L. reuteri Urob-7 exhibited the highest degradation rates for inosine and guanosine (82.10% and 88.78%, respectively) and strong xanthine oxidase (XOD) inhibitory activity (62.86%). In a HUA mouse model induced by inosine, guanosine, and potassium oxonate, L. reuteri Urob-7 intervention significantly reduced serum uric acid levels by 46.54%, restoring them to levels similar to control groups, and improved kidney function indicators. Moreover, Urob-7 reduced hepatic XOD activity by 37.6% and downregulated XOD expression in the intestines, decreasing excessive uric acid synthesis. It also significantly inhibited the NF-κB/NLRP3 inflammatory pathway, reducing the expression levels of NF-κB and NLRP3 in the kidneys by 39.3% and 47.6%, respectively. Furthermore, L. reuteri Urob-7 increased the abundance of short-chain fatty acid-producing bacteria (e.g., Ruminococcus and Intestinimonas) while reducing the proportion of pathogenic bacteria (e.g., Bacteroides and Anaerovorax), thus ameliorating gut microbiota dysbiosis and intestinal barrier dysfunction. In summary, L. reuteri Urob-7 effectively relieved HUA by modulating uric acid metabolism, suppressing inflammation, and improving gut microbiota balance. These results highlighted its potential as a promising candidate for HUA.

Irritable bowel syndrome (IBS) is a prevalent gastrointestinal disorder, often accompanied by low-grade inflammation, visceral hypersensitivity and gut microbiota dysbiosis. In this study, the therapeutic potential of Lactiplantibacillus plantarum LPPerfectus001 (L. plantarum 001) was investigated to alleviate IBS symptoms. Using an Lipopolysaccharides (LPS)-induced RAW264.7 macrophage model, L. plantarum 001 demonstrated significant anti-inflammatory properties by inhibiting Nitric Oxide production and downregulating pro-inflammatory cytokines. Furthermore, in a mouse model of IBS induced by Citrobacter rodentium infection and water avoidance stress, L. plantarum 001 intervention reduced fecal moisture, improved intestinal barrier integrity via up-regulating of ZO-1 and MUC2, and attenuated visceral hypersensitivity. Transcriptomic analysis combining with RT-qPCR revealed that L. plantarum 001 modulated the NF-κB signaling pathway and Th1/Th2 cell differentiation, reducing expression of key inflammatory genes. Additionally, 16S rRNA sequencing showed that L. plantarum 001 restored gut microbiota diversity, enriched beneficial butyrate-producing Odoribacter, and suppressed pro-inflammatory Pseudomonadota. These findings suggested that L. plantarum 001 alleviates IBS through multi-targeted mechanisms involving barrier repair, microbiota modulation, and anti-inflammatory signaling, highlighting its potential as a probiotic therapy for IBS.