Research On The Effect And Mechanism Of Resveratrol On Imrroving Antioxidat Capacity Of Porcine Skeletal Muscle Through Nrf2 Signaling Pathaway

Improving the antioxidant capacity of skeletal muscle is one of the important ways to improve meat quality in the field of animal nutrition research.Resveratrol(RES)is a plant polyphenol with multiple biological functions such as antioxidant and anti-inflammatory.Nrf2(Nuclear factor-erythroid 2-related factor 2)is an important redox-sensitive transcription factor.In this study,the experiment of adding RES to the diet to feed finishing pigs,combined with the RES treatment of Diquat(Diquat,DIQ)induced oxidative stress model cell experiments of porcine skeletal muscle satellite cells.We usedRNA-seq technology to carry out lncRNA sequencing analysis of the longissimus dorsi(LD)muscle of pigs,deeply discussing the effect and mechanism of RES to improve the antioxidant capacity of porcine skeletal muscles through the Nrf2 signaling pathway.It was hoped to provide a scientific basis for the future development of RES as a feed additive that could improve the antioxidant capacity of porcine skeletal muscle and improve meat quality.The main findings are as follows:1.Based on the Nrf2 signaling pathway to study the mechanism of resveratrol improving the antioxidant capacity of porcine skeletal muscles(1)Select 24 Duroc×Landrace×Yorkshire pigs with an average weight of about 65 kg as experimental animals,and randomly divided them into four groups,each with 6 pigs,which were the control group and three experimental groups.The control group was fed with a basic diet.The three experimental groups were supplemented with 200 mg/kg,400 mg/kg and 600 mg/kg RES on the basis of the basal diet.When the porcine weight reached 110 kg,the slaughter experiment was carried out,and the LD muscle tissue was collected.The results showed that: 1)RES significantly increased the activities of antioxidant enzymes including T-SOD,T-AOC,GSH-PX and CAT in the LD muscle of pigs,and significantly reduced the content of MDA,a marker of lipid peroxidation.Among them,the addition amount of 400 mg/kg and 600 mg/kg could achieve the best effect of improving the antioxidant capacity.2)RES activated the Nrf2 signaling pathway by down-regulating the expression of Keap1 gene,and up-regulated the expression of the downstream genes including HO-1,NQO1,GCLM and GCLC of the Nrf2 signaling pathway.Thereby,the expression of the main antioxidant enzyme genes including T-SOD,CAT and GSH-PX in the LD muscle of the pig were increased,and the antioxidant capacity of the LD muscle of the pig was improved.(2)The experimental results of DIQ-induced oxidative stress model of porcine skeletal muscle satellite cells showed that DIQ significantly increased the content of MDA and significantly reduced the activities of antioxidant enzymes including T-SOD,T-AOC,GSH-PX and CAT.This indicated that the oxidative stress model of porcine skeletal muscle satellite cells had been successfully established;RES treatment of this cell model could effectively activate the Nrf2 signaling pathway,increase the expression of antioxidant enzyme genes T-SOD,CAT and GSH-PX,and significantly increase the activity of antioxidant enzymes including T-SOD,T-AOC,GSH-PX and CAT.It shows that RES could effectively alleviate the oxidative stress of porcine skeletal muscle satellite cells caused by DIQ.2.LncRNA sequencing analysis of LD muscle tissueThe muscle tissues of the control group(Control)and the RES group(400 mg/kg)were subjected toRNA-seq sequencing analysis.The results showed that:(1)10680 transcripts were screened,of which 67 were differential lncRNA,56 were up-regulated lncRNA,and 11 were down-regulated.In addition,there are456 differential mRNAs,199 up-regulated mRNAs and 257 down-regulated mRNAs.(2)It was found that the differential lncRNA KEGG enriched signaling pathway homologous recombination,insulin signaling pathway and proteasome,the signaling pathway of differential mRNA significantly enriched Fox O signaling pathway,prolactin signaling pathway and transendothelial migration were all related to antioxidant function.(3)Real-time fluorescent quantitative PCR and sequencing results showed that,compared with the control group,the expression levels of five lncRNAs,including LNC＿007039,LNC＿009225,LNC＿001981,LNC＿006425 and LNC＿002608 in the LD of the RES group were significantly increased.The expressions of Nrf2,GCLM,HO-1,NQO1 and SOD1 were also significantly up-regulated.Therefore,RES could activate the Nrf2 signaling pathway by up-regulating the Nrf2 gene of LNC＿007039 in the LD muscle tissue,thereby improving the antioxidant capacity of the LD muscle.In summary,RES can increase the expression of major antioxidant enzyme genes by activating the Nrf2 signaling pathway,and increase the antioxidant enzyme activity in the LD muscle of pigs,thereby improve the antioxidant capacity of the skeletal muscle of pigs.