Protective Effectt Of Epalrestat Against Carbon Tetrachloride-induced Chronic Liver Injury In Mice And Its Mechanism

Objective:In this study,we explored the protective effect of epalrestat against carbon tetrachloride（CCl₄）-induced chronic liver injury in mice.The initially related protective mechanisms of epalrestat have been studied.To provide a reference direction for epalrestat as a hepatoprotective drug in the treatment of chemical liver injury.Methods:A total of 75 male mice were evenly divided into normal group（group A）,CCl₄control group（group B）,Diammonium glycyrrhizinate control group（group C）,low-dose epalrestat group（group D）and hing-dose epalrestat group（group E）.Mice in all groups except for group A were intraperitoneally injected with 20%CCl₄olive oil solution（2ml/kg）,twice a week for 8 weeks.After successful modeling,the mice in groups A and B were given normal saline by gavage,those in group C were given diammonium glycyrrhizinate 50mg/kg by gavage,and those of groups D and E were given epalrestat50mg/kg and 100mg/kg,respectively,by gavage,once a day for 4 consecutive weeks.The mice were anesthetized and their eyeballs were removed with ophthalmic tweezers to collect blood.The mice were killed and dissected to obtain livers.The serum levels of ALT and AST were detected by biochemical analyzer;liver pathology was observed by HE staining;the hepatocyte apoptosis rate were detected by TUNEL;mitochondrial membrane potential of hepatocytes were detected by fluorescence probe JC-1;the content of MDA and the activities of SOD,GSH-Px,and CAT in liver were deteced by ELISA;the protein expressions of Bcl-2,Bax and caspase-3 in liver were detected by Western blot.Results:1.The serum level of ALT and AST in group B were significantly higher than those in group A（P<0.05）,those in groups C,D and E were significantly lower than those in group B（P<0.05）,and there were no significant differences between group E and group D（P>0.05）.2.Liver pathology showed that hepatocyte in group A were neatly arranged without edema and necrosis;hepatocyte in group B were severely edema with bridging necrosis,disordered structure of liver tissue and aggregation of inflammatory cells;the degree of hepatocyte edema and histological disorder in group C,D and E was significantly reduced,hepatocyte necrosis and inflammatory cell infiltration was reduced,and the improvement of group E was more significant than group D.3.The apoptosis rate of hepatocytes in group B was significantly higher than that in group A（P<0.05）,that in group C and E was significantly lower than that in group B（P<0.05）,and there was no significant difference between group E and group D（P>0.05）.4.The mitochondrial membrane potential of hepatocyte in group B was significantly lower than that in group A（P<0.05）,that in groups C,D and E was significantly higher than that in group B（P<0.05）,and there was no significant difference between group E and group D（P>0.05）.5.The content of MDA in group B was higher than that in group A,but there was no significant difference（P>0.05）,that in groups D and E was significantly lower than that in group B（P<0.05）,and there was no significant difference in the content of MDA between group E and group D（P>0.05）.The activities of SOD,GSH-Px and CAT in group B were significantly lower than those in group A（P<0.05）,and those in groups C,D and E were significantly higher than those in group B（P<0.05）,and there were no significant differences in the activities of SOD,GSH-Px and CAT between group E and group D（P>0.05）.6.The protein expression of Bcl-2 in group B was significantly lower than that in group A,and the protein expression of Bax and caspase-3 in group B were significantly higher than those in group A（P<0.05）.The protein expression of Bcl-2 in groups C,D and E were significantly higher than that in group B,and the protein expression of Bax and caspase-3 in groups C,D and E were significantly lower than those in group B（P<0.05）.Compared with group D,the protein expression of Bax in group E was significantly decreased（P<0.05）,while the protein expression of Bcl-2 and Caspase-3 was not significantly different（P>0.05）.Conclusion:1.Epalrestat can reduce the levels of transaminase of CCl₄-induced chronic liver injury in mice and improve the pathological changes of liver injury.2.The protective effect of epalrestat on CCl₄-induced chronic liver injury in mice may be related to the reduction of oxidative stress in liver and hepatocyte apoptosis.3.This experiment provides theoretical basis for epalrestat to become a new drug for liver protection.