Changes Of PTRF/MG53/Pax7/?-catenin In Skeletal Muscle Of Rats In Exhaustive Exercise And Blunt Contusion And Its Mechanism

Objective:Wistar rats skeletal muscles were injured by One-time exhaustive exercise and contusion to investigate the variation of MG53/PTRF/Pax7/?-catenin in injured rats at immediate time as well as 24 and 48 hours later,and analyze their modulatory mechanism of skeletal muscle injury and repair.Methods:42 Wistar rats were randomly divided into 7 groups:(1)sedentary control group(C,n=6),(2)immediately after exhaustive exercise group(E0,n=6),(3)24 hours after exhaustive exercise group(E24,n=6),(4)48 hours after exhaustive exercise group(E48,n=6),(5)immediately after contusion group(DO,n=6),(6)24 hours after contusion group(D24,n=6),(7)48 hours after contusion group(D48,n=6).Sedentary control group sampling:Wistar rats were narcotized by intraperitoneal injection,and then draw blood in aortaventralis.Left gastrocnemius muscle was divided into two parts,one for Elisa and the other for Real-time PCR.Exhaustive exercise group and contusion group sampling:Wistar rats were sampled immediately or 24 and 48 hours later.Results:(1)PTRF RT-PCR results:comparing with group C,PTRF mRNA of skeletal muscle in group EO,E24,DO,D24 and D48 increased significantly(p<0.05,p<0.01).Comparing with group EO,PTRF mRNA of skeletal muscle in group E24 and E48 decreased significantly(p<0.05,p<0.01).Comparing with group DO,PTRF mRNA of skeletal muscle in group D24 and D48 decreased significantly(p<0.01).Comparing with exhaustive exercise groups,PTRF mRNA of skeletal muscle in contusion groups increased much more obviously.Elisa results:comparing with group C,PTRF of skeletal muscle in group EO and DO increased significantly(p<0.05);PTRF of serum in group DO decreased significantly(p<0.05).(2)MG53 RT-PCR results:comparing with group C,MG53 mRNA of skeletal muscle in group EO and DO increased significantly(p<0.05,p<0.01);MG53 mRNA of skeletal muscle in group E48 and D48 decreased significantly(p<0.05,p<0.01).Comparing with group EO,MG53 mRNA of skeletal muscle in group E48 decreased significantly(p<0.05).Comparing with group D0,MG53 mRNA of skeletal muscle in group D24 and D48 decreased significantly(p<0.01).Comparing with exhaustive exercise groups,PTRF mRNA of skeletal muscle in contusion groups increased much more obviously.Elisa results:comparing with group C,MG53 of skeletal muscle and serum in group EO increased significantly(p<0.05,p<0.01),but MG53 of skeletal muscle and serum in group D24 and D48 decreased significantly(p<0.05,p<0.01).(3)Pax7 RT-PCR results:comparing with group C,Pax7 mRNA of skeletal muscle in group E24 and E48 decreased significantly(p<0.05);Pax7 mRNA of skeletal muscle in group D24 and D48 decreased significantly(p<0.05),Pax7 mRNA of skeletal muscle in other group had no significant difference(p>0.05).Comparing with group E0,Pax7 mRNA of skeletal muscle in group E48 decreased significantly(p<0.05).Comparing with group D0,Pax7 mRNA of skeletal muscle in group D48 decreased significantly(p<0.01).Comparing with exhaustive exercise groups,PTRF mRNA of skeletal muscle in contusion groups decreased much more obviously.Elisa results:comparing with group C,Pax7 of skeletal muscle in group D0,D24 and D48 decreased significantly(p<0.05,p<0.01);Pax7 of skeletal muscle and serum in group E24 and D24 also decreased significantly(p<0.05).(4)?-catenin RT-PCR results:comparing with group C,?-catenin mRNA of skeletal muscle in group E0,E24,D0 and D24 decreased significantly(p<0.05,p<0.01);but P-catenin mRNA of skeletal muscle in group D48 increased significantly(p<0.05);P-catenin mRNA of skeletal muscle in group E48 had no significant difference(p>0.05).Comparing with group E0,?-catenin mRNA of skeletal muscle in group E24 and E48 had no significant difference(p>0.05).Comparing with group DO,Pax7 mRNA of skeletal muscle in group D48 increased significantly(p<0.01).Conclusions:(1)PTRF/MG53 protein and PTRF/MG53 mRNA of skeletal muscle in group EO and DO increased significantly,which indicated that PTRP/MG53 of skeletal muscle may induce cytomembrane repair mechanism to work at the early time both in exhaustive exercise groups and contusion groups.PTRF/MG53 protein decreased constantly after 24 and 48 hours in exhaustive exercise groups and contusion groups,the reduction may be compensatory for its foregoing increase.Comparing with exhaustive exercise groups,PTRF/MG53 launched more sensitively in contusion groups.(2)Pax7 protein and Pax7 mRNA of skeletal muscle had no difference significantly in exhaustive exercise groups,indicated that skeletal muscle satellite cells may not differentiate.Pax7 mRNA of skeletal muscle in group D48 decreased significantly,which indicated that skeletal muscle satellite cells may transform into skeletal progenitor cell as myofibril stem cells.Comparing with exhaustive exercise groups,Pax7 protein and Pax7 mRNA of skeletal muscle decreased more significantly after injured 48 hours in contusion groups.(3)?-catenin mRNA of skeletal muscle decreased significantly before 24 hours,which indicated that Wnt/?-catenin passageway in skeletal muscle satellite cells of both exhaustive exercise and contusion rats may be closed,?-catenin constantly decreased and skeletal muscle satellite cells may proliferate.While P-catenin mRNA of skeletal muscle in group D48 increased significantly,which indicated that Wnt/?-catenin passageway in Skeletal muscle satellite cells of contusion rats may work,p-catenin constantly accumulated in cells and Wnt/?-catenin passageway may regulate target gene so that skeletal muscle satellite cells can differentiate after injured 48 hours.Comparing with exhaustive exercise groups,skeletal satellite cells were activated apparently in contusion groups.