This study aims to investigate the effects of levan on the progression of hyperuricemia (HUA) rats and elucidate its underlying mechanisms. After levan intervention, both low and high-dose groups exhibited a significant decrease in serum uric acid (UA) levels, reaching 71.0 % and 77.5 %, respectively, compared to the model group. Furthermore, levan could alleviate renal pathological damage caused by glomerular cell vacuolation, inflammatory infiltration and collagen deposition. The results of enzyme activity assay and real-time fluorescence quantitative PCR showed that levan decreased UA production by inhibiting adenosine deaminase (ADA) activity and gene expression in liver; it upregulated ATP-binding cassette subfamily G member 2 protein (ABCG2) and organic anion transporter 1 (OAT1) transporter gene expression in the kidney, promoting UA excretion. Gut microbiome analysis indicated that levan regulated gut flora dysbiosis induced by HUA, resulting in up-regulated the abundance of beneficial bacteria (Muribaculaceae, Faecalibaculum, Bifidobacterium, and Lactobacillus) and decreased conditioned pathogenic bacteria (Escherichia_Shigella and Proteus). Non-targeted metabolomics showed changes in various serum metabolites associated with glycerophospholipid metabolism, lipid metabolism, and inflammation following oral administration of levan. Therefore, levan may be a promising functional dietary supplement for regulating the gut flora and remodeling of metabolic disorders in individuals with HUA.
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