Antifibrotic effects of luteolin on hepatic stellate cells and liver fibrosis by targeting AKT/mTOR/p70S6K and TGFβ/Smad signalling pathways.

Luteolin has been reported to exert antifibrogenic effects in CCl4 -induced hepatic fibrosis in mice. However, limited information is available on the cellular and molecular events responsible for this effect. This study focused on the action of luteolin on hepatic stellate cells (HSCs) and the relevant signalling molecules and pathways as well as the antifibrotic efficacy in multiple models of fibrosis. The in vitro effect of luteolin on rat HSCs and HSC-T6 cells was assessed using proliferation assays, invasion chamber, quantitative real-time PCR analysis and Western blotting. The in vivo effect of luteolin on progression of fibrosis was assessed in three experimental rat models induced by CCl4 , dimethylnitrosamine (DMN) and bile duct ligation (BDL). Luteolin inhibited proliferation, migration, collagen synthesis as well as expression of fibrosis-related genes in the activated HSCs and HSC-T6 cells stimulated with or without transforming growth factor-β1(TGFβ1) or platelet-derived growth factor (PDGF). Luteolin induced HSC apoptosis associated with the increased caspase 3 activity and p53 expression, and induced G1 arrest with the decreased expression of bcl-2, Cyclin E and p-Cdk-2. Moreover, luteolin significantly inhibited PDGF and TGFβ1-simulated phosphorylation of AKT and Smad pathway. In vivo study showed that luteolin administration markedly alleviated hepatic fibrosis along with reduced elevations of alanine aminotransferase and aspartate aminotransferase. HSCs were found to undergo apoptosis and decreased expression of p-Smad2 and p-AKT in luteolin-treated animals. This study demonstrates that luteolin prevents the progression of liver fibrosis through multiple mechanisms and indicates that luteolin has potential for effective treatment of liver fibrosis.

Li J ，Li X ，Xu W ，Wang S ，Hu Z ，Zhang Q ，Deng X ，Wang J ，Zhang J ，Guo C ... -  《-》

Propranolol prevents liver cirrhosis by inhibiting hepatic stellate cell activation mediated by the PDGFR/Akt pathway.

Propranolol is known to reduce portal pressure by decreasing blood flow to the splanchnic circulation and the liver. However, it is unknown if propranolol improves fibrogenesis and sinusoidal remodeling in the cirrhotic liver. The aim of this study was to investigate the therapeutic effects of propranolol on carbon tetrachloride (CCl4)-induced liver fibrosis in a mouse model and the intrinsic mechanisms underlying those effects. In this study, a hepatic cirrhosis mouse model was induced by CCl4 administration for 6 weeks. Propranolol was simultaneously administered orally in the experimental group. Liver tissue and blood samples were collected for histological and molecular analyses. LX-2 cells induced by platelet-derived growth factor-BB (PDGF-BB) were used to evaluate the anti-fibrogenic effect of propranolol in vitro. The results showed that treatment of mice with CCl4 induced hepatic fibrosis, as evidenced by inflammatory cell infiltration, collagen deposition and abnormal vascular formation in the liver tissue. All these changes were significantly attenuated by propranolol treatment. Furthermore, we also found that propranolol inhibited PDGF-BB-induced hepatic stellate cell migration, fibrogenesis, and PDGFR/Akt phosphorylation. Taken together, propranolol might prevent CCl4-induced liver injury and fibrosis at least partially through inhibiting the PDGF-BB-induced PDGFR/Akt pathway. The anti-fibrogenic effect of propranolol may support its status as a first-line treatment in patients with chronic liver disease.

Ding Q ，Li Z ，Liu B ，Ling L ，Tian X ，Zhang C ... -  《-》

Synergistic anti-liver fibrosis actions of total astragalus saponins and glycyrrhizic acid via TGF-β1/Smads signaling pathway modulation.

Huangqi decoction (HQD) is a well-known traditional Chinese herbal formulation, It is an effective treatment for consumptive disease and chronic liver diseases. It consists of Radix Astragali (Astragalus membranceus(Fisch.) Bge. Root, Huangqi) and Radix Glycyrrhizae (Glycyrrhiza uralensis Fisch., root and rhizome, Gancao). Total astragalus saponins (AST) is a main component of Radix Astragali and glycyrrhizic acid(GA) is a main component of Radix Glycyrrhizae. Our primary results showed that the combination of AST and GA had an obvious synergistic effect in reducing liver collagen deposition and decreasing serum alanine aminotransferase (ALT) activity in dimethylnitrosamine (DMN)-induced liver fibrosis. Through in vivo and in vitro experiments, we aimed at investigating the key anti-fibrosis signal pathway TGF-β1/Smads to further explore the synergistic mechanism of AST and GA. Two hepatic fibrosis animal models, bile duct ligation-induced (BDL) and DMN-induced, were utilized. Rats were treated orally with AST, GA or AST/GA, with the effects evaluated via liver histopathology, hydroxyproline (Hyp) levels, and α-SMA expression. In the hepatic stellate cell line JS-1, cells were treated with AST/GA for 24h, followed by a cell viability assessment using Cell Counting Kit-8(CCK-8) and Real-time PCR and Western blot analysis of α-SMA, ColⅠ and TGF-β1/Smads signaling pathway related components. The AST/GA combination attenuated liver tissue inflammation, collagen deposition, Hyp levels, and α-SMA expression in both BDL-and DMN-stimulated hepatic fibrosis rats. In vitro results showed that the AST/GA combination significantly inhibited JS-1 cell viability, significantly suppressed α-SMA, ColⅠ, TGF-β1, Smad2 and Smad3 mRNA and protein expression, as well reduced p-Smad2/3. Compared with AST or GA treatment alone, the AST/GA combination significantly reduced Smad3 mRNA expression levels and TGF-β1, Smad3, and p-Smad2/3 protein levels. AST and GA synergistically alleviated both BDL-and DMN-induced hepatic fibrosis via TGF-β1/Smads signaling pathway inhibition in hepatic stellate cells.

Zhou Y ，Tong X ，Ren S ，Wang X ，Chen J ，Mu Y ，Sun M ，Chen G ，Zhang H ，Liu P ... -  《-》

Ferulic acid attenuates liver fibrosis and hepatic stellate cell activation via inhibition of TGF-β/Smad signaling pathway.

Mu M ，Zuo S ，Wu RM ，Deng KS ，Lu S ，Zhu JJ ，Zou GL ，Yang J ，Cheng ML ，Zhao XK ... -  《Drug Design Development and Therapy》

Antifibrotic effects of tanshinol in experimental hepatic fibrosis by targeting PI3K/AKT/mTOR/p70S6K1 signaling pathways.

Peng R ，Wang S ，Wang R ，Wang Y ，Wu Y ，Yuan Y ... -  《-》