Guizhi-Shaoyao-Zhimu decoction attenuates monosodium urate crystal-induced inflammation through inactivation of NF-B and NLRP3 inflammasome

Ethnopharmacological relevance: Guizhi-Shaoyao-Zhimu decoction (GSZD), a classical traditional Chinese medicine (TCM) prescription, is used empirically to treat various types of arthritis in TCM clinical practice. However, the underlying mechanisms of GSZD on gouty inflammation are not totally elucidated. Aim of study: The purpose of this study is to investigate the effects of GSZD on peritoneal recruitment of neutrophils, production of proinflammatory mediators, activations of nuclear factor (NF)-Kappa B and nucleotide oligomerization domain-like receptor protein-3 (NLRP3) inflammasome in mice with monosodium urate crystal (MSU)-induced peritonitis (MIP). Materials and methods: Mice were intragastrically administered with GSZD for 7 days. After the last administration, mice were intraperitoneally injected with MSU. Peritoneal exudates of mice were harvested, and total peritoneal cells were calculated. Levels of interleukin (IL)-1 beta, IL-6 and monocyte chemotactic protein (MCP)-1 in peritoneal exudates were tested by enzyme-linked immunosorbent assay. Expressions of IL-1 beta, NLRP3, cysteinyl aspartate specific proteinase (caspase)-1, apoptosis-associated speck-like protein containing the caspase activation and recruitment domain (ASC), phosphorylated (p)-p65, inhibitor of NF-Kappa B (I Kappa B)alpha, p-I Kappa B kinase (IKK)beta, nuclear p65, p-mitogen-activated protein kinases (MAPKs) in peritoneal cells were analyzed by Western blot. Binding activity of NF-Kappa B to DNA was measured by a Trans AMTM kit for p65. Interaction between ASC and procaspase-1 was assessed by co-immunoprecipitation assay. Results: Total peritoneal cells, levels of IL-1 beta, IL-6 and MCP-1 were significantly reduced by GSZD treatment in peritoneal exudates of MIP mice. As for the activation of NF-Kappa B, GSZD treatment significantly reduced the levels of p-p65, p-IKK beta, nuclear p65 and p-MAPKs, enhanced the level of I Kappa B alpha and abated the binding ability of NF-Kappa B to DNA in peritoneal cells of MIP mice. As for the activation of NLRP3 inflammasome, GSZD treatment significantly reduced the levels of IL-1 beta, NLRP3 and caspase-1, and alleviated the interaction between ASC and procaspase-1 in peritoneal cells of MIP mice. Nevertheless, GSZD didn't remarkably change the level of ASC. Conclusions: These results suggest that GSZD attenuates the MSU-induced inflammation through inhibiting the activations of NF-Kappa B and NLRP3 inflammasome.