Fuzheng Huayu recipe alleviates liver fibrosis via inhibiting NLRP3 inflammasome activation in macrophages

Ethnopharmacological relevance: Fuzheng Huayu recipe (FZHY) is a commonly used Traditional Chinese Medicine formula for treating liver fibrosis in clinical settings. Despite its widespread use, the specific curative effects and underlying pharmacological mechanisms of FZHY in treating liver fibrosis are not yet fully understood. Aim and study: This study aims to investigate the antifibrotic mechanism of FZHY treatment by exploring its effects on the activation of NOD-like receptor protein 3 (NLRP3) inflammasome in macrophages. Materials and methods: In order to investigate the impact of FZHY on the activation and priming of NLRP3 inflammasome in clinical trials and animal experiments using immunohistochemistry and Western blotting. Twenty-four C57BL/6 mice were used to induce liver fibrosis by feeding a diet that contained 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC). To study inflammasome function, Lipopolysaccharide (LPS)/adenine triphosphate (ATP) induced NLRP3 inflammasome activation was induced in bone marrow-derived macrophages (BMDMs) isolated from wild mice. The effects of macrophage NLRP3 inflammasome activation on the function of hepatic stellate cells (HSCs) were explored by treating primary HSCs with preconditioned media from BMDMs culture. Results: FZHY treatment resulted in the downregulation of NLRP3 protein expression and inhibition of its priming and activation in both human fibrotic livers and DDC-induced liver fibrosis. Furthermore, FZHY was observed to block the activation of the NLRP3 inflammasome pathway, which can lead to excessive inflammatory cytokine release in supernatants and cell lysates in response to LPS and ATP. Lastly, treatment with FZHY was able to inhibit the activation of HSCs induced by supernatants from macrophages. Conclusions: FZHY has been shown to potentially prevent NLRP3 inflammasome activation in macrophages which can result in the suppression of HSCs activation. Ultimately, these effects may lead to the improvement of liver fibrosis. The ability of FZHY to act on this novel mechanism represents an important aspect of its therapeutic potential for liver fibrosis.