Protective Effects And Action Mechanism Of The Tibetan Medicine Yajima (Chrysosplenium Nudicaule) On Mice With Intrahepatic Cholestasis Induced By ANIT

Background: Intrahepatic cholestasis,IC is a clinical syndrome that causes liver diseases due to bile acid accumulation in liver due to structural and functional disorders of liver cells or capillary bile ducts.At present,the drugs for treating IC are very limited and there are serious adverse reactions.The characteristic Tibetan medicine "Ya Ji Ma"(Chrysosplenium nudicaule Bunge)is a good medicine for Tibetan medicine in clinical treatment of hepatobiliary diseases,but no modern pharmacodynamic evaluation and related mechanism research report have been found so far.Objective: To evaluate the effect of C.nudicaule on IC-type liver injury and explore its related mechanisms,so as to provide modern pharmacological evidence for the clinical application of Tibetan medicine "Ya Ji Ma" and lay the foundation for its further development and utilization.Methods: A mouse model of IC-type liver injury was established by induction of α-naphthalene isothiocyanate(ANIT).The levels of serum transaminase,bilirubin,bile acid AST,ALT,ALP,DBIL,TBIL and TBA in mice after intervention of Extract of C.nudicaule,ECN were detected by full-automatic biochemical analyzer.The activities of SOD,GSH and MDA in liver homogenate were detected by colorimetry.Pathological changes of liver tissue in mice were observed by pathological sections.RT-PCR was used to measure m RNA expression evaluation of Bsep,Cyp7a1,Fxr,Mrp2,Shp,Ntcp and other genes in liver tissue.The expression of BSEP,CYP7A1,FXR,MRP2,SHP,NTCP protein in liver of mice was determined by western-blot method.Results:(1)ECN can reduce the levels of AST,ALT,ALP,DBIL,TBIL and TBA in serum of model mice in a dose-dependent manner,increase the activities of SOD and GSH in liver homogenate of mice(P < 0.01,P < 0.05),and reduce the content of MDA(P < 0.01,P < 0.05).Pathological sections of mouse liver showed that ECN could improve pathological changes of model mouse liver.(2)The activity evaluation results of ECN extraction fractions with different polarities showed that its ethyl acetate fraction and n-butanol fraction could reduce the levels of AST,ALT,ALP,DBIL,TBIL and TBA in serum of model mice in a dose-dependent manner(P < 0.01,P < 0.05);(3)m RNA analysis results showed that ECN could significantly change the expression level of bile acid metabolism related genes,such as Bsep,Fxr,Mrp2 m RNA expression significantly up-regulated(P < 0.01,P < 0.05),while Cyp7a1 expression significantly down-regulated(P < 0.01,P < 0.05).The ethyl acetate part and n-butanol part can significantly increase m RNA expression of Shp and Ntcp in liver tissue of model mice.(4)Protein expression results showed that the ethyl acetate part and nbutanol part of ECN could significantly change the expression level of bile acid metabolism related proteins in model mice,such as BSEP,FXR,MRP2,SHP,NTCP protein expression was significantly up-regulated(P < 0.01,P < 0.05),while CYP7A1 expression was significantly down-regulated(P < 0.01,P < 0.05).Conclusion: The extract of C.nudicaule has the effect of reversing intrahepatic cholestasis.Its effective parts are ethyl acetate part and n-butanol part.Its mechanism of action may be related to inhibiting lipid peroxidation,reducing liver cell damage,activating FXR and its target protein,reducing bile acid synthesis and increasing bile acid excretion.This study provides a modern pharmacological basis for the clinical application of the characteristic Tibetan medicine Ji Ma in Tibetan medicine.