Commensal Enterococcus faecalis W5 ameliorates hyperuricemia and maintains the epithelial barrier in a hyperuricemia mouse model.

Objective: The intestine is responsible for approximately one-third of uric acid (UA) excretion. The effect of commensal Enterococcus faecalis (E. faecalis), one of the most colonized bacteria in the gut, on UA excretion in the intestine remains to be investigated. The aim of this study was to evaluate the effect of commensal E. faecalis on UA metabolism and gut microbiota.

Methods: The 16S rRNA gene sequencing was used to examine the species of Enterococcus in mouse fecal content. E. faecalis strain was isolated from mouse feces and identified to be E. faecalis W5. The hyperuricemia (HUA) animal model was established with yeast-rich forage and 250 mg·kg ·day potassium oxonate. Oral administration of E. faecalis W5 was given for 20 days, serving as the Efa group.

Results: Disrupted intestinal barrier, activated proinflammatory response and low UA excretion in the intestine were found in HUA mice. After E. faecalis W5 treatment, the gut barrier was restored and serum UA level was decreased. Additionally, fecal and intestinal UA levels were elevated, intestinal urate transporter ABCG2 and purine metabolism were upregulated. Moreover, short-chain fatty acid levels were increased, and intestinal inflammation was ameliorated.

Conclusions: Commensal E. faecalis W5 ameliorated HUA through reversing the impaired gut barrier, promoting intestinal UA secretion by regulating ABCG2 expression, and decreasing intestinal UA synthesis by regulating purine metabolism. The results may provide the potential for developing treatments for HUA through the intestine.