Oral matrine alleviates CCl4-induced liver fibrosis via preserved HSP72 from modulated gut microbiota

Hepatic fibrosis is intricately associated with dysregulation of gut microbiota and host metabolomes. Our previous studies have demonstrated that matrine can effectively reduce hepatosteatosis and associated disorders. However, it is poorly understood whether the gut microbiota involved in the attenuation of liver fibrosis by matrine. Herein we explored a novel mechanism of how oral administration of matrine alleviates liver fibrosis by modulating gut microbiota. Administration of matrine not only potently ameliorated liver fibrosis in carbon tetrachloride (CCl4)-induced mice, but also significantly preserved hepatic heat shock protein 72 (HSP72) in vivo and in vitro. Matrine was failed to reduce liver fibrosis when HSP72 upregulation was blocked by the HSP72 antagonist VER-155008. Also, consumption of matrine significantly alleviated gut dysbiosis and fecal metabonomic changes in CCl4-treated mice. Transplanted the faces of matrine-treated mice induced a remarkable upregulation of HSP72 and remission of fibrosis in liver in CCl4-exposed mice and inhibition of TGF-β1-induced inflammatory response and epithelial-mesenchymal transition (EMT) in AML-12 cells. Furthermore, deficiency of HSP72 partly reversed the intestinal microbial composition that prevented matrine from reducing CCl4-induced liver fibrosis in mice. This study reveals the "gut microbiota-hepatic HSP72" axis as a key mechanism of matrine in reducing liver fibrosis and suggest that this axis may be targeted for developing other new therapies for liver fibrosis.