Project description:Characterization of hepatic stellate cells (HSC) genes in the normal liver or diverse liver fibrotic models by single cell RNA sequencing.
Project description:Characterization of genes specifically expressed in mouse primary quiescent hepatic stellate cells (HSC) compared to the whole liver by RNA-sequencing and single cell RNA sequencing as well as effect of UDP-glucose treatment on mouse primary HSC.
Project description:Gene expression of paired samples of hepatic stellate cells (HSC) and hepatocyte cell culture (HCC) treated with conditioned media of HSC cells
Project description:Liver fibrosis is characterized by the activation of perivascular hepatic stellate cells (HSCs), the release of fibrogenic nano-sized extracellular vesicles (EVs) and increased HSC glycolysis. Nevertheless, how glycolysis in HSCs coordinates fibrosis amplification through tissue zone-specific pathways remains elusive. Here, we demonstrate that HSC-specific genetic inhibition of glycolysis reduced liver fibrosis. Moreover, spatial transcriptomics revealed a fibrosis-mediated upregulation of EV-related pathways in the liver pericentral zone, which was abrogated by the glycolysis genetic inhibition. Mechanistically, glycolysis in HSCs upregulated the expression of EV-related genes such as RAB31 by enhancing histone-3-lysine-9 acetylation on the promoter region, which increased EV release. Functionally, these glycolysis-dependent EVs increased fibrotic gene expression in recipient HSC. Furthermore, EVs derived from glycolysis-deficient mice abrogated liver fibrosis amplification in contrast to glycolysis-competent mouse EVs. In summary, glycolysis in HSCs amplifies liver fibrosis by promoting fibrogenic EV release in the hepatic pericentral zone, which represents a potential therapeutic target.
Project description:Hepatic stellate cell (HSC) activation induced by transforming growth factor β (TGF-β1) plays a pivotal role in the fibrogenesis. The complex downstream mediators of TGF-β1 are largely unknown. Here, proteomics analysis and biological validation demonstrated that methionine adenosyltransferase 2A (MAT2A) was significantly upregulated in a CCl4-induced fibrosis mice model and a small molecule NPLC0393, known to block TGF-β1/Smad3 signaling, inhibited its upregulation. In HSC cells, TGF-β1 induced elevation of MAT2A and MAT2β expression as well as reduction of S-adenosylmethionine (SAM) content, which further promoted HSC activation. Functionally, in vivo and in vitro knockdown of MAT2A alleviated CCl4- and TGF-β1-induced HSC activation, whereas in vivo overexpression of MAT2A facilitated hepatic fibrosis and abolished therapeutic effect of NPLC0393. TGF-β1 induced p65 phosphorylation and NF-κB activation, thereby promoted the transcription of MAT2A and its protein expression. In addition, overexpression of p65 abrogated NPLC0393 mediated inhibition of HSC activation. This study identified a novel pathway TGF-β1/p65/MAT2A that was involved in the regulation of intracellular SAM contents and liver fibrogenesis, suggesting that this pathway is a potential therapeutic target for hepatic fibrosis.
Project description:Hepatic stellate cell (HSC) activation induced by transforming growth factor β (TGF-β1) plays a pivotal role in the fibrogenesis. The complex downstream mediators of TGF-β1 are largely unknown. Here, proteomics analysis and biological validation demonstrated that methionine adenosyltransferase 2A (MAT2A) was significantly upregulated in a CCl4-induced fibrosis mice model and a small molecule NPLC0393, known to block TGF-β1/Smad3 signaling, inhibited its upregulation. In HSC cells, TGF-β1 induced elevation of MAT2A and MAT2β expression as well as reduction of S-adenosylmethionine (SAM) content, which further promoted HSC activation. Functionally, in vivo and in vitro knockdown of MAT2A alleviated CCl4- and TGF-β1-induced HSC activation, whereas in vivo overexpression of MAT2A facilitated hepatic fibrosis and abolished therapeutic effect of NPLC0393. TGF-β1 induced p65 phosphorylation and NF-κB activation, thereby promoted the transcription of MAT2A and its protein expression. In addition, overexpression of p65 abrogated NPLC0393 mediated inhibition of HSC activation. This study identified a novel pathway TGF-β1/p65/MAT2A that was involved in the regulation of intracellular SAM contents and liver fibrogenesis, suggesting that this pathway is a potential therapeutic target for hepatic fibrosis.
Project description:Activation and migration of hepatic stellate cells (HSCs) followed by matrix deposition are characteristics of liver fibrosis. Several studies have shown the importance of hepatocyte and endothelial cell-derived extracellular vesicles (EVs) in liver pathobiology. However, less is known about the role of HSC-derived EVs in liver diseases. In this study, we investigated the molecules released through HSC-derived EVs and whether these can promote fibrosis.
