ABSTRACT
Objective:To explore the therapeutic mechanism of Canhuang tablets on the mRNA and protein expression of farnesoid X receptor (FXR), uridine diphosphate glucuronosyltransferase 1A1 (UGT1A1) and multidrug resistance associated protein 2 (MRP2) in the liver of jaundiced rats induced by α-naphthalene isothiocyanate (ANIT). Method:The rats were divided into normal group, model group, Canhuang tablets (CHP) group and ursodeoxycholic acid tablets (UDCA) group. The jaundice model was reproduced by ANIT. After the intervention of the corresponding drugs, the contents of total bilirubin (TBIL), total bile acid (TBA), alanine aminotransferase (ALT), aspartate aminotransferase (AST) and alkaline phosphatase (ALP) in serum and the liver histopathology were examined to evaluate the therapeutic effect of CHP. The relative mRNA and protein expressions of FXR, UGT1A1 and MRP2 in rat liver tissues were detected by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot. Result:CHP can significantly reduce the increase of TBIL, TBA, ALT, AST and ALP caused by ANIT in rat serum, and inhibit the liver pathological changes, which showed that the removing jaundice effect of CHP was better than UDCA. Compared with the normal group, ANIT significantly inhibited the mRNA levels of FXR, UGT1A1 and MRP2 in rat liver tissues after modeling (P<0.01). Compared with the model group, CHP and UDCA significantly increased the mRNA levels of target genes of each protein after intervention (P<0.01), and CHP was superior to UDCA in improving the mRNA level of bilirubin metabolizing enzyme UGT1A1 (P<0.01). In the aspect of affecting protein expression, compared with the normal group, ANIT modeling significantly increased the expression of FXR in rats (P<0.05). CHP intervention showed a tendency to promote the expression of FXR, while UDCA did not, but there was no significant difference between them. In the aspects of promoting bilirubin metabolism and bile excretion, the expressions of UGT1A1 and MRP2 were significantly decreased by ANIT modeling (P<0.01), while the expressions of UGT1A1 and MRP2 proteins were significantly increased after treatment of CHP (P<0.01). CHP was superior to UDCA in increasing the expression of bilirubin and bile acid efflux protein MRP2 (P<0.01). Conclusion:The jaundice abating mechanism of CHP is related to activating FXR mRNA expression in liver, promoting the mRNA and protein expression of bilirubin metabolizing enzyme UGT1A1 and bile acid transporter MRP2, improving liver metabolism of free bilirubin and promoting bile acid excretion from the liver, and alleviating cholestatic liver injury.
ABSTRACT
Objective:To explore the mechanism of treatment of jaundice with Canhuang tablets by molecular docking. Method:The compounds of Canhuang tablets were screened in traditional Chinese medicine systems pharmacology database and analysis platform(TCMSP),and targets for treatment of jaundice were collected from the comparative toxicogenomics database(CTD) and DrugBank database.Molecular docking was carry out on the LibDock module of Discovery Studio 2016 software to evaluate the compound-target interaction,and network characteristics were analyzed. Result:A total of 37 compounds in Canhuang tablets had strong interaction on 14 targets,such as pregnane receptor(PXR),constitutive androstane receptor(CAR),farnesoid X receptor(FXR),et al.These targets played an important role in the treatment of jaundice by regulating bilirubin metabolism,regulating bile acid synthesis and transport,inhibiting immune and inflammatory response,and affecting the formation of collagen in the liver.The compound-target network analysis found that moupinamide,canadine,quercetin,demethoxycurcumin,obacunone,curcumin,corchoroside A,berlambine,alnustone,naringenin were the possible main active compounds of Canhuang tablets,which could interact with more than 7 targets. Conclusion:Molecular docking reveals the possible active compounds and the mechanism of treatment of jaundice with Canhuang tablets,and which is conducive to improvement of quality control standard of this preparation and study of its mechanism for jaundice.