Effects And Mechanism Associated With Huangqi And Danshen Treatment On Skeletal Muscle Atrophy Caused By Denervation In Rats

Objective: To investigate the effects and mechanism of Astragalus combined with Salviamiltiorrhiza on skeletal muscle atrophy caused by denervation in rats and to provide theexperiment basics for traditional Chinese medicine treament, on muscle atrophy.Methods: Healthy adult male20SD rats were divided randomly into control group (group A, n=10)and treatment group (group B, n=10). The right sciatic nerve was cut off about1cm from each animal toestablish the right lower limb denervated gastrocnemius atrophy model. Control group wasadministrated3ml saline by intraperitoneal injection same fout, treatment group was administratedwith Astragalus and Danshen1.5ml respectively once a day.After denervation,animal,s diet andactivity were observed.5rats were killed by overdose of anesthesia on second and third weekrespectively. Muscle wet weight ratio, muscle fiber cross-sectional area, total protein, apoptosis rate,FoXO3a, MAFbx mRNA and protein expression, in gastrocnemius were measured.Results:1.General observation: Transection of sciatic nerve established a denervated skeletalmuscle atrophy in model rats.2.Gastrocnemius muscle wet weight ratio: Muscle wet weight ratio of two groupsdecreased with the extension of denervation time. The muscle wet weight ratio of thetreatment group was higher than that in control group on second and third week. Thedifference was statistically significant (P <0.05).3.Cross-sectional area of muscle fiber: Muscle fiber cross-sectional area of two groupswere reduced significantly.The treatment group cross-sectional area was higher than that incontrol group onsecond and third week. The difference wasstatistically significant (P<0.05).4.Total protein level: Total protein levels of two groups are decreased gradually with the extension of denervation time. The total protein levels in treatment group was higher thanthose in control group on second and third week.The difference was statistically significant(P<0.05).5.Detection of apoptosis: apoptosis rate of two groups were increased with the extensionof denervation time. The apoptosis rate in treatment group was lower than those in thecontrol group on second and third week.The difference was statistically significant (P<0.05).6. FoXO3a and MAFbx mRNA expression: FoXO3a and MAFbx mRNA expression oftwo groups were increased gradually with the extension of denervation time. FoXO3a andMAFbx mRNA expression in treatment group were lower than those in the control groupon second and third week. The difference was statistically significant(P <0.05).7. Protein expression of FoXO3a and MAFbx: FoXO3a, MAFbx protein expression oftwo groups were increased gradually with the extension of denervation time. second,3weeks, group FoXO3a and MAFbx protein expression in treatment group were lower thanthose in the control groupthe. The difference was significant statistically(P <0.05).Conclusion:1. Huangqi and Danshen delay muscle atrophy in early denervated skeletal muscle.2.They decrease the apoptosis rate and may restrain the apoptosis of denervated skeletalmuscle.3.They reduce the levels of mRNA and protein of FoXO3a and MAFbx and may restrainthe protein degradation induced by FoXO3a and MAFbx.