Objective To investigate the effect of Sclareol(SCL)on LX-2 hepatic stellate cell activation and CCl4-induced liver fibrosis in mice,and to further explore its mechanism.Methods A total of 40 Kunming mice were randomly divided into healthy group,model group(10%CCl4)and SCL administration group,and silybin positive control group(10%CCl4+100 mg·kg-1 Silybin),and SCL administration group was divided into low SCL(10%CCl4+20 mg·kg-1 SCL)and high dose group(10%CCl4+40 mg·kg-1 SCL).Mice in all groups were intraperitoneally injected with 10%olive oil-diluted CCl4 three times a week for four weeks,except for the healthy group.Starting from the third week,the dosing group was given different doses of SCL by gavage daily,and the positive control group was given silybin daily,and the mice were sacrificed and serum and liver tissue were collected after four weeks.In whole animal experiments,biochemical kits were used to detect the changes in the serum levels of glutamate aminotransferase(ALT)and aspartate aminotransferase(AST)in mice with liver fibrosis.Hematoxylin-eosin(HE),Sirius Red and Masson staining were used to detect microstructural changes and collagen deposition in liver tissues.Immunohistochemistry was used to detect the expression of fibrosis marker proteins α-smooth muscle actin(α-SMA)and fibrous collagen I.in liver tissues.In vitro,LX-2 human hepatic stellate cells were used for normal culture in the blank group,and the activation of LX-2 hepatic stellate cells was induced by transforming growth factor-β1(TGF-β1)in the model group,and the SCL administration group was divided into SCL low-dose group(5 ng·mL-1 TGF-β1+10 μmol·L-1 SCL)and high-dose group(5 ng·mL-1 TGF-β1+20 μmol·L-1 SCL).Subsequently,Transwell and EdU assays were used to detect the effects of SCL on the migration and proliferation of LX-2 cells.The expression of fibrosis marker proteins α-SMA and Collagen I.affected by SCL was detected by immunofluorescence.Western blot was used to detect the expression of related proteins in TGF-β/Smad pathway.Results In animal experiments,compared with the model group,SCL could significantly improve the liver function indexes and liver histopathological changes in liver fibrosis model mice.In addition,in vitro cell experiments,compared with the model group,SCL can effectively inhibit the migration and proliferation of hepatic stellate cells and inhibit their activation.Further studies showed that compared with the model group,SCL significantly up-regulated the expression of Smad7 protein and significantly down-regulated the phosphorylation levels of Smad2 and Smad3 proteins.Conclusion SCL has a significant alleviating effect on CCl4-induced liver fibrosis and TGF-β1-induced LX-2 activation in mice,and the mechanism may be related to the regulation of TGF-β/Smad pathway.

Objective To investigate the effect of Sclareol(SCL)on LX-2 hepatic stellate cell activation and CCl4-induced liver fibrosis in mice,and to further explore its mechanism.Methods A total of 40 Kunming mice were randomly divided into healthy group,model group(10%CCl4)and SCL administration group,and silybin positive control group(10%CCl4+100 mg·kg-1 Silybin),and SCL administration group was divided into low SCL(10%CCl4+20 mg·kg-1 SCL)and high dose group(10%CCl4+40 mg·kg-1 SCL).Mice in all groups were intraperitoneally injected with 10%olive oil-diluted CCl4 three times a week for four weeks,except for the healthy group.Starting from the third week,the dosing group was given different doses of SCL by gavage daily,and the positive control group was given silybin daily,and the mice were sacrificed and serum and liver tissue were collected after four weeks.In whole animal experiments,biochemical kits were used to detect the changes in the serum levels of glutamate aminotransferase(ALT)and aspartate aminotransferase(AST)in mice with liver fibrosis.Hematoxylin-eosin(HE),Sirius Red and Masson staining were used to detect microstructural changes and collagen deposition in liver tissues.Immunohistochemistry was used to detect the expression of fibrosis marker proteins α-smooth muscle actin(α-SMA)and fibrous collagen I.in liver tissues.In vitro,LX-2 human hepatic stellate cells were used for normal culture in the blank group,and the activation of LX-2 hepatic stellate cells was induced by transforming growth factor-β1(TGF-β1)in the model group,and the SCL administration group was divided into SCL low-dose group(5 ng·mL-1 TGF-β1+10 μmol·L-1 SCL)and high-dose group(5 ng·mL-1 TGF-β1+20 μmol·L-1 SCL).Subsequently,Transwell and EdU assays were used to detect the effects of SCL on the migration and proliferation of LX-2 cells.The expression of fibrosis marker proteins α-SMA and Collagen I.affected by SCL was detected by immunofluorescence.Western blot was used to detect the expression of related proteins in TGF-β/Smad pathway.Results In animal experiments,compared with the model group,SCL could significantly improve the liver function indexes and liver histopathological changes in liver fibrosis model mice.In addition,in vitro cell experiments,compared with the model group,SCL can effectively inhibit the migration and proliferation of hepatic stellate cells and inhibit their activation.Further studies showed that compared with the model group,SCL significantly up-regulated the expression of Smad7 protein and significantly down-regulated the phosphorylation levels of Smad2 and Smad3 proteins.Conclusion SCL has a significant alleviating effect on CCl4-induced liver fibrosis and TGF-β1-induced LX-2 activation in mice,and the mechanism may be related to the regulation of TGF-β/Smad pathway.