Effects Of Electroacupuncture On Protein Degradation And Synthesis Factors Of Denervated Gastrocnemius Muscle In Rats

ObjectiveTo explore the effects of electroacupuncture?EA?on protein degradation related factors Fork-head protein 3a?FoxO3a?,Muscle atrophy F-box?MAFbx?,Myogenic differentiation antigen 1?Myod1?and protein synthesis related factors Mammalian target of rapamycin?mTOR?,Phosphorylation mTOR(p-mTOR^Ser2448),70-KD ribosomal protein S6kinase?p70S6K?,Phosphorylation p70S6K(p-p70S6K^Thr389)protein and gene expression in rat gastrocnemius denervated atrophy,from regulating degradation metabolism and anabolic metabolism of muscle protein,to investigate the possible mechanism of electroacupuncture on delaying denervated gastrocnemius atrophy.MethodsThirty male SD rats were randomly divided into sham operation group?S?,model group?M?and EA group?EA?,each group of ten.M and EA group were clamped right sciatic nerve to establish atrophy model of skeletal muscle.Since one day after modeling,EA group accepted electroacupuncture on its right“Zusanli”?ST 36?“Huantiao”?GB 30?for10 min,once a day,respectively for 14 days.Then,the gastrocnemius muscles were obtained after intervention,and the wet weight ratio of gastrocnemius muscles were calculated.The cross-sectional area?CSA?and diameter of muscle fibers were measured after HE staining.The protein relative expression of FoxO3a,MAFbx,Myod1,mTOR,p-mTOR^Ser2448,p70S6K and p-p70S6K ^Thr389 were tested with Western blotting.The gene relative expression of FoxO3a,MAFbx,Myod1,mTOR and p70S6K were detected with real-time quantitative polymerase chain reaction.ResultsMuscular atrophy indexes include the ratio of wet weight of gastricnemius muscle,CSA and diameter decrease.Compared with S group,the wet weight ratio of the gastrocnemius muscle,CSA and diameter of the muscle fibers were smaller in M and EA group?P<0.01?,and EA group was larger than M group?P<0.01?.Compared with S group,the protein and gene relative expression of protein degradation related factors FoxO3a,MAFbx and Myod1 increased significantly?P<0.01?,and the protein synthesis related factors mTOR,p-mTOR^Ser2448,p70S6K,p-p70S6K^Thr389protein relative expression increased significantly?P<0.01?,and mTOR,p70S6K gene relative expression increased?P<0.05?in M group.Compared with M group,the protein expression of protein degradation related factors FoxO3a and MAFbx protein and gene decreased significantly?P<0.01?,and Myod1 increased significantly?P<0.01?,while the protein expression of protein synthesis related factors mTOR,p-mTOR^Ser2448,p70S6K,p-p70S6K^Thr389hr389 protein relative expression increased?P<0.05?,and mTOR,p70S6K gene relative expression increased?P<0.05?in EA group.ConclusionEA can delay denervated gastrocnemius atrophy.The mechanism may relate to the decrease of FoxO3a and MAFbx,the increase of Myod1,mTOR,p-mTOR^Ser2448,p70S6K,p-p70S6K^Thr389,activating mTOR/p70S6K signaling pathway,slowing down the speed of protein degradation of gastrocnemius muscle,promoting muscle protein synthesis,and affecting the imbalance relationship between muscle protein degradation metabolism and anabolic metabolism.