Characterization,Antioxidant Activity Of Cyclcarya Paliurus(Batal.) Iljinskaja Polysaccharide And Its Effect On Genome-wide DNA Methylation In High-fat Diet-induced Mice

Polysaccharide is one of the important active components of Cyclocarya paliurus leaves.In order to explore the effects of Cyclocarya paliurus(Batal.)Iljinskaja polysaccharide on antioxidant activities and genome-wide DNA methylation in high-fat diet-induced mice,the DEAE(diethylamine base ethyl cellulose)-cellulose column was used to separate and purify the polysaccharide of Cyclocarya paliurus(Batal.)Iljinskaja,then the purified polysaccharide was named of CPP-?.Fourier transform-infrared pectroscopy(FT-IR),high performance liquid gel permeation chromatography(HPGPC),gas chromatography(GC)and scanning electron microscopy(SEM)were used to analyze the structure characterizations of CPP-?.The ICR mice were divided into normal control group,model control group,low-dosage group,moderate-dosage group,high-dosage group and positive control group.And these groups were intragastrically administered 15ml/kg·BW/d of distilled water,15 ml/kg·BW/d of high-fat emulsion(HFE),150,300,600mg/kg·BW/d of CPP-? and 5 mg/kg·BW/d of simvastatin,repectively.After the 28-day experiment,the contents of TC,TG,LDL-C,HDL-C and antioxidant status were measured in serum and hepatic.The genome-wide DNA methylation experiment was conducted to observe the lipid molecular mechanism of high-fat diet-induced mice administered with CPP-?.The experimental results demonstrated that:(1)CPP-?,comprised of two polysaccharides,with Mw of 307 kDa and 3.7 kDa,was consisted of rhamnose,mannose,glucose and galactose in a molar ratio of1.00 : 0.78 : 3.22 : 0.45.(2)Oral administration of CPP-?,significantly decreased levels of serum and hepatic total cholesterol(TC),triglycerides(TG),low-density lipoprotein cholesterol(LDL-C),and increase high-density lipoprotein(HDL-C)in high-fat diet-induced mice(P < 0.01 or P < 0.05)?(3)CPP-? significantly decreased the contents of serum and hepatic malondialdehyde(MDA)and lipid peroxide(LPO),and improved total antioxidant capability(T-AOC)content and glutamate pyruvate transaminase(GPT),superoxide dismutase(SOD),glutathione peroxidase(GSH-PX)activities,respectively(P < 0.01 or P < 0.05)?(4)CPP-? reduced the level of genome-wide DNA methylation in the liver of high-fat diet-induced mice,which played a lipid-lowering effect by regulating the AMPK(AMP-activated protein kinase)signaling pathway,fatty acid metabolism pathway,fatty acid biosynthesis pathway and adipocytokine signaling pathway.