Paeoniflorin Regulates LXRs-STAT3 Signaling Pathway To Improve The Process Of Liver Fibrosis

Objective:Studies have shown that Paeoniflorin(PAE)has a good liver protection effect;In this study,HSCs cells stimulated by TGF-? and Balb/c mice intraperitoneally injected with thioacetamide(TAA)were used to establish liver fibrosis models in vitro and in vivo,and to explore the regulatory and improving effects of PAE on liver fibrosis through LXRs-STAT3 signaling pathway and its potential molecular mechanism.Methods:HSCs cells were stimulated by TGF-? and treated with PAE of 0-200 ?M for 24 hours.The effect of PAE on the survival rate of HSCs cells was detected by MTT method.HSCs was incubated with PAE at concentrations of 6.25,12.5,25,50,100 ?M.After 24 hours,the total protein of HSCs was extracted for Western blot analysis,and the expression levels of LXRa,LXR?,STAT3 and other proteins in HSCs cells were detected.RNA was extracted and quantitatively analyzed by PCR.The expression level of RNA was detected and further verified by immunofluorescence staining.Mice were randomly divided into four groups:normal group,TAA model group,low dose PAE(10mg/kg)group and high dose PAE(20mg/kg)group,with 5 mice in each group.The normal group was fed a standard diet,and the TAA model group and PAE administration group were intraperitoneally injected with TAA(100 or 200 mg/kg)to establish a model of liver fibrosis in mice.The administration group was intragastrically administered with PAE 10 mg/kg or 20 mg/kg per day for 4 weeks.After 6 hours of the last administration,the serum and liver tissues of the mice were collected,and the levels of alanine aminotransferase(ALT)and aspartate aminotransferase(AST)in the serum were measured by the kit,Paraffin sections of liver tissues were stained with H&E,Masson,Sirius red and IHC immunohistochemistry to observe the pathological changes of liver tissues.The expression of LXRa,LXR?,and STAT3 in liver was detected by Western blotting,quantitative PCR and immunofluorescence.Results:In vitro experiments,MTT results showed that PAE of 0-100 ?M had no significant effect on the growth rate of HSCs.PAE can significantly reduce the expression of hepatic fibrosis markers a-SMA and Collagen-I in activated HSCs.PAE can activate the expression of LXRa and LXR? and inhibit the release of various inflammatory factors such as P2X7r,NLRP3 and caspase-1,and further activate STAT3 signal factor,increase its phosphorylation modification expression to inhibit liver fibrosis.In vivo experiments showed that PAE can inhibit the expression of ALT and AST in serum of mice with liver injury induced by TAA.It can be judged by H&E,Masson and Sirius red staining that PAE can alleviate liver pathological changes in mice.PAE inhibited the expression of a-SMA,Collagen-I protein and gene,activated and up-regulated the expression of LXRa,LXR? protein and gene,prevented the cascade reaction of inflammatory factors such as P2X7r,NLRP3 and caspase-1,and then activated STAT3 and up-regulated the expression of P-STAT3.Conclusion:PAE can reduce the expression of a-SMA and Collagen-I,and effectively inhibit the release of pro-inflammatory factors.It may ameliorate the development of liver fibrosis by regulating LXRs-STAT3 signaling pathway.