Study Of Resveratrol On Liver Lipid Metabolism,Energy Metabolism And RNA Methylation Modification

Natural active substances are very important for maintaining the homeostasis of metabolism in the body and are widely used for the prevention and treatment of metabolic diseases.Resveratrol,a polyphenolic non-flavonoid natural compound containing a quinone structure,is mainly found in plants such as peanuts,grapes,and gourds,and has a wide range of pharmacological and biological functions.In modern livestock production,lipid metabolism and energy metabolism disorders are important factors affecting the health of livestock and poultry,and the liver is an important metabolic organ.N6-methyladenine(m6A)is a reversible epigenetic RNA modification that is present at the transcriptional level of the nitrogen or oxygen atom of S-adenosylmethionine,regulating mRNA stability,splicing,export,localization and translation.In addition,more than one-third of the genes are methylated with m6 A in the mouse and human genomes.In this study,the effects of resveratrol on lipid metabolism,energy metabolism and m6 A RNA methylation modification in obese mice induced by high-fat diet and hepatocytes were studied,respectively,to provide theoretical basis and reference for animal husbandry and clinical treatment.In the first experiment,the effects of dietary resveratrol on growth performance,liver function,oxidative stress and energy metabolism in mice induced by high-fat diet.A total of forty healthy SPF-class C57BL/6J male black rats were selected and pre-raised for 3 weeks.The 8-week-old mice were randomly divided into four groups of 10 according to their weight.They were low-fat daily food group(LFD),low-fat daily food+276 mg/kg resveratrol group(LFDR),high-fat daily food group(HFD),and high-fat daily food+400 mg/kg resveratrol group(HFDR).The experiment lasted for 12 weeks.The results showed that:(1)Compared with LFD mice,the final weight and average daily gain(ADG)of HFD mice were significantly increased,and the average daily feed intake(ADFI)and liver weight were significantly decreased(P<0.05).Compared with mice in HFD group,the final body weight and ADG of the HFDR group were significantly decreased,and ADFI and liver weight were significantly increased(P<0.05).(2)Compared with LFD mice,the serum levels of AST and ALT in HFD mice increased significantly,while liver AST and ALT decreased significantly(P<0.05).Compared with HFD mice,the levels of AST and ALT in serum and liver of HFDR mice fed with resveratrol were significantly decreased(P<0.05).(3)Compared with the LFD group,the serum levels of AST and ALT in the HFD group were significantly increased,and AST and ALT in the liver were significantly decreased(P<0.05).Compared with the HFD group,AST and ALT in the serum of the HFDR group fed with resveratrol were significantly decreased,and the AST content in the liver was significantly increased(P<0.05).(4)Compared with mice in the LFD group,the activities of CAT,MDA and LPO in the liver of mice fed the high-fat diet were significantly increased,and the expression of SOD3 mRNA increased significantly(P<0.05).Compared with the HFD group,the CAT,MDA and LPO in the HFDR group with resveratrol were significantly decreased(P<0.05),and the expressions of CAT,SOD3 and GPX1 in the liver were not significantly changed(P>0.05).(5)Compared with LFD mice,the activities of HK,PK and SDH in the liver of HFD mice were significantly decreased,and the expressions of MDH1,Sdha and PGC-1α were significantly decreased(P<0.05).Compared with mice in HFD group,the activities of HK and PK in liver of mice in HFDR group were significantly increased,and the expressions of Hk2,Pkm,Cs,MDH1 and Sdha genes in liver of mice in HFDR group were significantly increased(P<0.05).In the second experiment,the effects of dietary resveratrol on liver lipid metabolism and m6 A RNA methylation in obese mice induced by high-fat diet.The experimental design is the same as test 1.The results showed that:(1)In comparison with LFD mice,the Lee’s index of the HFD group was significantly increased,the abdominal and epididymal fat weight and its coefficient were significantly increased,and the weight of the perirenal fat and its coefficient were significantly increased(P<0.05).Compared with the HFD group,the addition of resveratrol reduced the Lee’s index of the HFDR group(P>0.05),the abdominal and epididymal fat weight and its coefficient decreased significantly,and the bilateral renal fat coefficient decreased significantly(P<0.05),(2)In HFD mice,the number of hepatocyte nuclei decreased,the boundary was unclear,accompanied by fat vacuoles and inflammation.After treatment with resveratrol,the hepatocyte volume and fat vacuoles of HFDR mice decreased.(3)Compared with the LFD group,the serum levels of TC and LDL in the HFD group were significantly increased,and the contents of TG,TC and LDL in the liver were significantly increased(P<0.05).Compared with the HFD group,the addition of resveratrol resulted in a significant decrease in serum LDL content,a significant increase in HDL content,and a significant decrease in TG and TC levels in the liver(P<0.05).(4)Compared with the LFD group,the expression of ACC,SREBP-1c and PPARy mRNA in the liver of HFD group was significantly increased(P<0.05).Compared with the HFD group,the expression of PPARa,FATP4 and FABP4 in the liver of HFDR group was significantly increased,and the expression of ACC and PPARy was significantly decreased(P<0.05).(5)Compared with LFD group,the m6A content in the liver of HFD group decreased(P>0.05),the expression of ALKBH5 and FTO decreased significantly(P<0.05),and the contents of METTL3,FTO,ALKBH5 and YTHDF2 protein increased(P>0.05).Compared with mice in HFD group,the m6A content in the liver of mice in HFDR group tended to decrease(P>0.05),and the expressions of METTL3,FTO,ALKBH5 and YTHDF2 were significantly increased(P<0.05).In the third experiment,the effects of resveratrol on HepG2 lipid metabolism and energy metabolism and m6 A RNA methylation modification were determined.A solution was prepared by dissolving resveratrol in DMSO to treat HepG2 cells in logarithmic growth phase.The results showed that:(1)The proliferation rate of HepG2 cells was determined by MTT assay,and 100 μmol/L resveratrol was used for the test.(2)The content of TG and TC in HepG2 cells treated with resveratrol decreased(P>0.05).Resveratrol treatment significantly increased the gene expression of PPARa,PPARγ,ACC,FAS and FABP4 in HepG2 cells(P<0.05).(3)Resveratrol significantly increased the expression of PGC-1α,MFN2,MTFR1,UQCRO,MTERF1,PINK1,HOWE1,FIS1,PDHB,TNF-2α,COX Ⅳ and ECSIT(P<0.05).(4)Resveratrol treatment significantly reduced the expression of HepG2 cells METTL3,YTHDF2,and ALKBH5 mRNA(P<0.05),making the expression of HepG2 cell YTHDF2 protein and m6 A content have a tendency to decrease(P>0.05).(5)Compared with the siControl processing group,knocking down YTHDF2 significantly increased the expression of PPARa,PPARy,ACC,FAS,FATP4,SREBP-1c(P<0.05),significant increase in energy metabolism related genes PGC-1α,TNF-2α,MFN2,MTFR1,NDUFAF4,UQCRQ,MTERF1,OPA1,COXⅣ,PINK1,ECSIT,HOW1,BNIP3,PDHB mRNA expression(P<0.05).Based on the above test results,it was found that:(1)Dietary resveratrol supplementaion can reduce the body weight,feed intake,blood lipid and body fat content of mice fed high-fat diet,alleviate oxidative stress and liver injury caused by obesity,reduce the level of m6 A,and regulate liver lipid metabolism and energy metabolism.(2)Resveratrol can activate the lipid metabolism and energy metabolism of HepG2 cells,and decrease the levels of YTHDF2 and m6A.Knockdown of YTHDF2 also activates the expression of lipid metabolism and energy metabolism,suggesting that resveratrol regulates metabolism by affecting m6A.