Effects of Polysaccharides from Dicliptera chinensis(L.)Nees.on TLR4/NF-κB Signaling Pathway in Cell Model of Non-alcoholic Fatty Liver

[Objectives]To observe the effects of polysaccharides from Dicliptera chinensis(L.)Nees.on the expression of TLR/NF-κB pathway related proteins in HepG2 cells induced by oleic acid,and to explore the possible mechanism of polysaccharides from D.chinensis(L.)Nees.in the treatment of non-alcoholic fatty liver disease(NAFLD).[Methods]HepG2 cells were induced with oleic acid to establish a non-alcoholic fatty liver cell model.After intervention with 0.25 and 0.5 mg/mL of D.chinensis(L.)Nees.polysaccharides,the ALT and AST activity and TG and TC contents were detected with kits,and the changes in the expression of CDK5,TLR4,p-NF-κB and NF-κB were analyzed using Western-blotting.[Results]In the HepG2 cells induced with oleic acid,the ALT and AST activity increased significantly,the TG and TC contents increased significantly,and the expression levels of CDK5,TLR4 and p-NF-κB proteins up-regulated significantly.In the HepG2 cells intervened with D.chinensis(L.)Nees.polysaccharides,the activity of ALT and AST,the contents of TG and TC,and the expression levels of CDK5,TLR4 and p-NF-κB proteins all reduced significantly.[Conclusions]Polysaccharides from D.chinensis(L.)Nees.may interfere with NAFLD by inhibiting the TLR4/NF-κB pathway.

Effect and Mechanism of Dicliptera chinensis Polysaccharide on miR-141/AMPK/SIRT1 Signaling Pathway in Rats with NAFLD

[Objectives]Non-alcoholic fatty liver disease(NAFLD)rat model was established by feeding high-fat and high-sugar fodder to rats,and the protective effect of Dicliptera chinensis polysaccharide(DCP)on NAFLD rats was studied to explore its potential mechanism.[Methods]45 SD rats were randomly divided into 4 groups:normal control group,model control group and DCP treatment groups(100 and 300 mg/kg).The rats in the normal control group were fed with ordinary fodder,and the rats in other groups were fed with high-fat and high-sugar diet for 14 weeks to establish NAFLD model.From the 9^(th)week,the rats in the DCP treatment groups were given different doses of DCP by intragastric administration(5 mL/kg)for 6 weeks.After the last intragastric administration,the rats fasted for 16 h,and the serum and liver of rats were collected for detection.Hematoxylin-eosin(HE)staining was conducted to observe the histopathological changes of rat liver,and alanine aminotransferase(ALT),aspartate aminotransferase(AST),superoxide dismutase(SOD),glutathione peroxidase(GSH-Px),malondialdehyde(MDA),triglyceride(TG),total cholesterol(TC),low density lipoprotein cholesterol(LDL-C),and high density lipoprotein cholesterol(HDL-C)were detected by biochemical method.Interleukin-6(IL-6),interleukin-1β(IL-1β),tumor necrosis factor(TNF-α)and micrornA-141(micro RNA-141)were detected by reverse transcription-polymerase chain reaction(RT-PCR).The expression of SIRT1 and adenosine 5'-monophosphate(AMP)-activated protein kinase(AMPK)in rat liver was detected by western blot.[Results]Compared with the model control group,the inflammatory damage and steatodegeneration of rats in the DCP groups were relieved to varying degrees,and the number of lipid vacuoles significantly reduced.The ALT,AST,TC,TG and LDL-C content in the serum and MDA content in the liver tissue decreased to varying degrees,while the HDL-C,SOD and GSH-Px content increased.The expression of SIRT1 and AMPK increased,while the expression of miR-141,TNF-α,IL-6 and IL-1βdeclined,and the DCP 300 mg/kg treatment group had better improvement effect.[Conclusions]DCP had a certain protective effect on NAFLD rats,which may be related to the regulation of miR-141/AMPK/SIRT1 signaling pathway.

Ethyl Acetate Fraction of Dicliptera chinensis(L.)Juss.Ameliorates Liver Fibrosis by Inducing Autophagy via PI3K/AKT/m TOR/p70S6K Signaling Pathways

Objective:To investigate the molecular mechanism underlying the anti-hepatic fibrosis activity of ethyl acetate fraction Dicliptera chinensis(L.)Juss.(EDC)in human hepatic stellate cells(HSCs)in vitro and in a carbon tetrachloride(CCl4)-induced hepatic fibrosis mouse model in vivo.Methods:For in vitro study,HSCs were pre-treated with platelet-derived growth factor(10 ng/mL)for 2 h to ensure activation and treated with EDC for 24 h and 48 h,respectively.The effect of EDC on HSCs was assessed using cell counting kit-8 assay,EdU staining,transmission electron microscopy,immunofluorescence staining,and Western blot,respectively.For in vivo experiments,mice were intraperitoneally injected with CCl4(2μL/g,adjusted to a 25%concentration in olive oil),3 times per week for 6 weeks,to develop a hepatic fibrosis model.Forty 8-week-old male C57 BL/6 mice were divided into 4 groups using a random number table(n=10),including control,model,positive control and EDC treatment groups.Mice in the EDC and colchicine groups were intragastrically administered EDC(0.5 g/kg)or colchicine(0.2 mg/kg)once per day for 6 weeks.Mice in the control and model groups received an equal volume of saline.Biochemical assays and histological examinations were used to assess liver damage.Protein expression levels ofα-smooth muscle actin(α-SMA)and microtubule-associated protein light chain 3 B(LC3 B)were measured by Western blot.Results:EDC reduced pathological damage associated with liver fibrosis,downregulated the expression ofα-SMA and upregulated the expression of LC3 B(P<0.05),both in HSCs and the CCl4-induced liver fibrosis mouse model.The intervention of bafilomycin A1 and rapamycin in HSCs strongly supported the notion that inhibition of autophagy enhancedα-SMA protein expression levels(P<0.01).The results also found that the levels of phosphoinositide(PI3 K),p-PI3 K,AKT,p-AKT,mammalian target of rapamycin(mTOR),p-mTOR,and p-p70 S6 K all decreased after EDC treatment(P<0.05).Conclusion:EDC has anti-hepatic fibrosis activity by inducing autophagy and might be a potential drug to be further developed for human liver fibrosis therapy.