Regulation Of Sodium Butyrate On Bovine Skeletal Muscle Satellite Cells Under Oxidative Stress

In recent years,with the improvement of economic level and life quality,people’s requirements for beef quality are constantly improving.The quality of beef directly affects the economic benefits of beef cattle industry.Skeletal muscle is the largest energy metabolizing organ of mammalian body.Studying its development process and muscle fiber formation is very important for the industrial upgrading of meat and livestock industry.In addition to genetic factors,oxidative stress caused by various environmental changes and diseases will be involved in the regulation of muscle development and meat quality changes of beef cattle.Butyric acid is a short-chain fatty acid metabolized in the intestinal tract of domestic animals.It can be used as a histone deacetylase inhibitor to activate a variety of signaling molecules and participate in the regulation of energy metabolism and muscle fiber differentiation in animals.In order to clarify the effects of oxidative stress on bovine Muscle fibers,an oxidative stress model is established using bovine Skeletal Muscle Satellite Cells(SMSCs)to explore the effects of oxidative stress on the differentiation types of bovine SMSCs muscle fibers.Sodium butyrate is also used for treatment.To explore the regulatory effect of sodium butyrate on bovine oxidative stress SMSCs.The main contents are as follows:1.An oxidative stress model of bovine SMSCs was constructed by H2O2,and the optimal treatment concentration and time of H2O2 were screened by CCK-8 cell viability assay.The changes of ROS and SOD in the oxidative stress model of bovine SMSCs were detected by DCFH-DA fluorescence probe and WST-8,respectively,to clarify the reliability of the model.The expression changes of MyHC I,MyHC Ⅱ a,MyHC Ⅱ b and MyHC Ⅱ x genes of four myofiber types in bovine SMSCs skeletal muscle after oxidative stress were detected by qRT-PCR,and the expression changes of fast myosin heavy chain and slow myosin heavy chain after oxidative stress were detected by Western Blot.The results showed that oxidative stress inhibited the expression of type I myofibers and promoted the expression of type II myofibers in bovine skeletal muscle satellite cells;2.The regulatory effect of sodium butyrate on oxidative stress bovine SMSCs was verified.The optimal concentration and time of sodium butyrate treated cells were firstly screened by CCK-8 cell viability assay.After co-treatment of cells with sodium butyrate and H2O2,the oxidative stress response of bovine SMSCs was measured.Sodium butyrate treatment significantly inhibited the increase of ROS level and decrease of SOD level in bovine SMSCs after oxidative stress;the expression of type I myofibrils and type II myofibrils in bovine SMSCs significantly increased and decreased after sodium butyrate treatment,which alleviated the changes of gene levels of four myofibril types in bovine SMSCs after oxidative stress;meanwhile,sodium butyrate treatment promoted the expression of slow myosin At the same time,sodium butyrate treatment promoted the expression of slow myosin heavy chain and inhibited the expression of fast myosin heavy chain in bovine SMSCs,alleviating the changes of myosin heavy chain expression level after oxidative stress in bovine SMSCs;indicating that sodium butyrate played a significant alleviating effect on H2O2-induced oxidative stress in bovine SMSCs;3.The effect of P300 on oxidative stress of bovine SMSCs treated by sodium butyrate was verified.After C646 was used to inhibit the expression of P300 in bovine oxidative stress SMSCs,the regulatory effect of sodium butyrate was explored again.The results showed that oxidative stress significantly increased the expressions of HDAC3 and HDAC6 genes,and significantly decreased the expression of P300 genes in bovine SMSCs.Sodium butyrate treatment significantly down-regulated the expressions of HDAC3 and HDAC6 genes in bovine SMSCs,significantly increased the expression of P300 gene,and promoted the expression of P300 at the protein level.Sodium butyrate treatment reversed the expression changes of HDAC3,HDAC6 and P300 gene levels induced by oxidative stress.After treatment with P300 inhibitor C646,the effects of sodium butyrate on ROS levels,SOD levels,muscle fiber type gene expression levels and myosin heavy chain expression levels of bovine SMSCs under oxidative stress were reversed.In this study,it is clear that oxidative stress inhibits the expression of slow oxidative myofibers and promotes the expression of enzymatic myofibers in bovine SMSCs.Sodium butyrate treatment alleviated oxidative stress in bovine SMSCs and promoted the expression of slow oxidative myofibers and inhibited the expression of enzymatic myofibers;sodium butyrate may regulate oxidative stress and myofiber type in bovine SMSCs through the P300 pathway.This study will provide a reference for the artificial regulation of bovine myofibrillogenesis and development.