Silymarin Inhibits NLRP3 Inflammasome To Improve Nonalcoholic Fatty Liver Disease Via Regulating Nrf2 Antioxidant Pathway

ObjectiveTo investigate the mechanism of Silymarin affecting the progression of Nonalcoholic steatohepatitis(NASH).Methods1.After the intervention of solvent,(PA+LPS)and(PA+LPS+Silymarin)to Hep G2 cells,western-blot were used to detect the expression index of Nrf2,SIRT2,NLRP3 and their downstream Casp1 P45 and Casp1 P20 proteins,q PCR were used to estimate the expression levels of Nrf2,HO-1,NQO-1 m RNA and fluorescence were used to detect the change of ROS metabolism.2.Screened out the best si RNA of Nrf2-si RNA.Then after the intervention of(PA+LPS+ si NC),(PA+LPS+Silymarin+si NC),(PA+LPS+Silymarin+si Nrf2),(PA+LPS + si Nrf2)to Hep G2 cells,the above indicators were detected again.3.After the intervention of solvent,HFD and(HFD+Silymarin)to the mice,the H.E staining pathological sections of the liver were evaluated,and the changes in the expression levels of NLRP3 and Nrf2 proteins in the liver were detected by IHC.Results1.After the intervention of(PA + LPS)to the Hep G2 cells,the expression levelsof Nrf2,SIRT2 protein of Hep G2 cells inthe PL group decreased,and the Nrf2 m RNA decreased,HO-1,NQO-1 m RNA increased,andthe NLRP3,Casp1 p20 protein increased,and the IOD of ROS fluorescenceincreased.The data changes of SIRT2,NLRP3,Casp1 p20 expression and Nrf2,HO-1 m RNA and the IOD of ROS fluorescence compared with the CON group weresignificant different(P<0.05).After the intervention of(PA + LPS)and Silymarin,the expression levels of Nrf2 and SIRT2 protein of Hep G2 cells in the SB group increased,and the expression levels of Nrf2,HO-1 and NQO-1 m RNA increased too,and the NLRP3,Casp1 p20 protein increased,and the IOD of ROS fluorescence decreased.The data changes of above compared with the PL group were significant different(P<0.05).2.After the intervention of si RNA to the Hep G2 cells,the expression levels of Nrf2,SIRT2 protein of Hep G2 cells in SBsi group decreased,and the NLRP3,Casp1p20 protein increased,and the expression levels of Nrf2,HO-1 and NQO-1 m RNA increased too,and the IOD of ROS fluorescence increased.The data changes of above compared with the SB group were significant different(P<0.05).3.After HFD intervention to the mice in the HFD group,the weight of them increased significantly,and the immunohistochemical test of paraffin sections of the liver showed that the expression level of Nrf2 protein in the liver decreased and NLRP3 protein increased.The data changes of above compared with the CON group were significant different(P<0.05).After the same HFD intervention and the Silymarin drug treatment,the weight of the mice in the SB group decreased significantly.The immunohistochemical test showed that the expression level of Nrf2 protein in the liver tissue increased,and the expression level of NLRP3 protein decreased.The data changes of above compared with the HFD group were significant different(P<0.05).Conclusions1.It was suggested that Silymarin could enhance the antioxidant effect of Nrf2 in Hep G2 and inhibit NLRP3 inflammasome to play an anti-cell damage role.2.Silymarin inhibited NLRP3 after specifically inhibiting Nrf2 protein function,suggesting that Silymarin inhibited NLRP3 inflammasome by regulating Nrf2 function.3.It was suggested that Silymarin could play an anti-hepatocyte damage role by promoting Nrf2 in mouse liver and inhibiting NLRP3 inflammasome in mouse liver.