Impact of Camellia japonica Bee Pollen Polyphenols on Hyperuricemia and Gut Microbiota in Potassium Oxonate-Induced Mice

Abstract

<i>Camellia japonica</i> bee pollen is one of the major types of bee pollen in China and exhibits antioxidant and anti-inflammatory activities. The aims of our study were to evaluate the effects and the possible mechanism of <i>Camellia japonica</i> bee pollen polyphenols on the treatment of hyperuricemia induced by potassium oxonate (PO). The results showed that <i>Camellia japonica</i> bee pollen ethyl acetate extract (CPE-E) owned abundant phenolic compounds and strong antioxidant capabilities. Administration with CPE-E for two weeks greatly reduced serum uric acid and improved renal function. It inhibited liver xanthine oxidase (XOD) activity and regulated the expression of urate transporter 1 (URAT1), glucose transporter 9 (GLUT9), organic anion transporter 1 (OAT1), organic cation transporter 1 (OCT1) and ATP-binding cassette superfamily gmember 2 (ABCG2) in kidneys. Moreover, CPE-E suppressed the activation of the toll-like receptor 4/myeloid differentiation factor 88/nuclear factor-κB (TLR4/MyD88/NF-κB) signaling pathway and nucleotide-binding oligomerization domain-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome in PO-treated mice, and related inflammatory cytokines were reduced. CPE-E also modulated gut microbiota structure, showing that the abundance of <i>Lactobacillus</i> and <i>Clostridiaceae</i> increased in hyperuicemic mice. This study was conducted to explore the protective effect of CPE-E on hyperuricemia and provide new thoughts for the exploitation of <i>Camellia japonica</i> bee pollen.