Table 1.

Mechanism of targeted gut microbiota in the treatment of gout.

	Type	Effect	Mechanism
Inulin (Guo et al., 2021)	Prebiotics	Reduces serum uric acid level, relieves inflammation and repairs intestinal epithelial barrier. Enhances microbial diversity and increases the relative abundance of beneficial bacteria.	Increase ABCG2 expression in the intestinal tract. Down-regulate XOD expression and activity in the liver of KO mice.
Chicory (Bian et al., 2020)	Prebiotics	Reduces serum uric acid level and increases fecal uric acid. Repairs intestinal mucosal injury.	Increases the number of probiotics and reduce the number of pathogenic bacteria to restore intestinal microbiota. Reduces the inflammatory response of the LPS/TLR4 axis by down-regulating the inflammatory pathways of serum LPS and TLR4/NF-κB in the kidney, thus promoting the excretion of uric acid in the kidney
Tuna meat oligopeptides (TMOP) (Han et al., 2020)	Prebiotics	Reduces hyperuricemia and renal inflammatory phenotype.	Reprograms the uric acid metabolic pathway to inhibit NLRP3 inflammasome activation and toll-like receptor 4/bone marrow differentiation factor 88/NF-kappaB (TLR4/MyD88/NF-κB) signal pathway, and the phosphorylation of p65 murine NF-κ B. Repairs the intestinal epithelial barrier. Reverses intestinal flora imbalance and increases short-chain fatty acids production.
Camellia japonica bee pollen polyphenols (CPE-E) (Xu et al., 2021)	Prebiotics	Reduces serum uric acid level and improve renal function.	Inhibits hepatic xanthine oxidase (XOD) activity and regulates the expression of URAT1, GLUT9, OAT1, OCT1 and ABCG2 in the kidney. Changes gut microbiota structure and increases the abundance of beneficial bacteria and the content of short-chain fatty acids. Decreases NLRP3 inflammasome and related inflammatory cytokines.
Sea cucumber hydrolysates (Wan et al., 2020)	Prebiotics	Reduces hyperuricemia and renal inflammation caused by diet.	Inhibits uric acid biosynthesis and promote uric acid excretion. Down-regulates pro-inflammatory cytokine transcription and up-regulates anti-inflammatory cytokine transcription. Inhibits TLR4/MyD88/NF-κB signal pathway. Increases the abundance of beneficial lactobacillus and short-chain fatty acids producers and reduces the abundance of opportunistic pathogens to alleviate intestinal microbiota dysfunction.
β-carotin and green tea powder (Feng et al., 2022)	Prebiotics	Relieves acute gout attack.	Reduces the joint swelling and pain in mice with gout. Reduces serum uric acid and pro-inflammatory cytokines levels. Improves the gut microbiota profile and reduces the metabolic levels of purines and pyrimidines.
Enteromorpha prolifera (Li et al., 2021)	Prebiotics	Reduces hyperuricemia and reverses kidney damage.	Decreases serum uric acid, serum urea nitrogen, serum xanthine oxidase (XOD), and hepatic XOD. Up-regulates UA excretion genes, such as ABCG2, OAT1, and NPT1. Down-regulates UA absorption gene URAT1 was down-regulated. Maintains intestinal flora stability, which is closely related to the regulation of hyperuricemia.
Hexapeptides derived from Apostichopus japonicus hydrolysate (Fan et al., 2022)	Prebiotics	Reduces uric acid biosynthesis and reabsorption.	Inhibits uric acid biosynthesis and reabsorption to reduce serum uric acid. Reduces renal inflammation and inhibits the activation of NLRP3 inflammasome. Decreases the richness and diversity of gut microbiota and changes the composition of phylum and genus levels. Changes miRNA expression in the kidney.
Anserine supplementation (Han et al., 2021)	Prebiotics	Promotes uric acid excretion. Has anti-inflammatory effects.	Increases hypoxanthine phosphate ribose transferase expression. Inhibits the uric acid synthesis by activating uric acid transporter. Inhibits NLRP3 inflammasome and TLR4/MyD88/NF-κB pathway. Regulates the composition and abundance of gut microbiota during hyperuricemia and renal inflammation.
Nuciferine (Wang et al., 2020)	Prebiotics	Relieves hyperuricemia and improves renal function.	Interferes with the gut microbiota and restores the metabolic balance of hyperuricemia rats. Reverses the levels of creatinine and creatine in rats to some extent after nuciferine treatment.
Fisetin (Ren et al., 2021)	Prebiotics	Prevents CKD induced by hyperuricemia.	Regulates tryptophan metabolism and aromatics receptor (AHR) activation mediated by gut microbiota.
Curcumin (Xu et al., 2021)	Prebiotics	Reduces the level of uremic toxin and improves renal inflammation and fibrosis.	Regulates gut microbiota’s structure and improves intestinal permeability. Increases beneficial bacteria and reduces pathogens.
AJOP (Lu et al., 2021)	Prebiotics	Relieves hyperuricemia.	Regulates uric acid metabolism, inhibits NLRP3 inflammasome and NF- κB signal pathway activation, and repairs intestinal epithelial barrier. Globally changes the spectrum of GIT microflora.
Lactobacillus brevis DM9218 (Wang et al., 2019)	Probiotics	Reduce serum uric acid level.	Down-regulates xanthine oxidase expression and activity stimulated by inflammatory cytokines.
Limosilacto-bacillus fermentum JL-3 (Wu et al., 2021)	Probiotics	Attenuates oxidative stress and inflammation induced by UA and regulates UA-induced flora imbalance in hyperuricemia mice.	Degrades UA in the intestine and reduces the amount of UA reabsorbed by intestinal epithelium into circulation. Contains purine-degrading lactobacillus strains and improves defecation activity, thus reducing fecal excretion of UA. Regulates gut microbiota’s structure and function.
Qu-Zhuo-Tong-Bi Decoction (QZTBD) (Wen et al., 2020)	Traditional Chinese medicine	Relieves acute gout attack.	Recovers the imbalance of gut microbiota and enhances SCFA formation. Inhibits intestinal barrier function, key glycolysis-related enzymes, and inflammatory factors production.
Fecal microbiota transplantation (Liu et al., 2020; Han et al., 2020; Xie et al., 2022)		Reduces serum uric acid level.	Restores damaged intestinal barrier function.