RESUMO
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-ß1-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.
RESUMO
Diets() rich in fat are a major() cause() of metabolic disease(), and nutritional() food has been widely() used() to counteract the metabolic disorders such() as obesity() and fatty() liver(). The present study investigated the effects of oleuropein-enriched extract() from Jasminum grandiflorum L. flowers (OLE-JGF) in high-fat diet() (HFD)-fed mice and oleic acid() (OA)-treated AML-12 cells. Treatment() of HFD-fed mice with 0.6% OLE-JGF for 8 weeks significantly reduced body and liver() weights, as well as attenuating lipid dysmetabolism and hepatic steatosis. OLE-JGF administration() prominently suppressed the mRNA expressions() of monocyte chemoattractant protein()-1 (MCP-1) and cluster of differentiation 68 (CD68), and it also downregulated acetyl-CoA carboxylase (ACC) and fatty() acid() synthase (FAS) as well as sterol-regulatory-element()-binding protein() (SREBP-1c) in the liver(). Meanwhile, mitochondrial DNA and uncoupling protein() 2 (UCP2) were upregulated along with the increased expression() of mitochondrial biogenic promoters including liver() kinase B1 (LKB1), peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α), nuclear() factor()-erythroid-derived 2-like 2 (Nrf2), and mitochondrial transcription factor() A (Tfam), but did not change AMP-activated protein() kinase (AMPK) in liver(). The lipid droplets were decreased significantly after treatment() with 80 µM oleuropein for 24 h in OA-induced AML-12 cells. Furthermore, oleuropein significantly inhibited ACC mRNA expression() and upregulated LKB1, PGC-1α, and Tfam mRNA levels, as well as increasing the binding level of LKB1 to PGC-1α promoter in OA-induced cells. These findings indicate() that OLE-JGF reduces hepatic lipid deposition in HFD-fed mice, as well as the fact that OA-induced liver() cells may be partly() attributed to upregulation of the LKB1-PGC-1α axis, which mediates hepatic lipogenesis and mitochondrial biogenesis. Our study provides a scientific() basis() for the benefits and potential() use() of the J. grandiflorum flower as a food supplement() for the prevention() and treatment() of metabolic disease().