title: Electrical stimulation based on chronaxie reduces atrogin-1 and myoD gene expressions in denervated rat muscle.
abstract: Denervation induces muscle fiber atrophy and changes in the gene expression rates of skeletal muscle. Electrical stimulation (ES) is a procedure generally used to treat denervated muscles in humans. This study evaluated the effect of ES based on chronaxie and rheobase on the expression of the myoD and atrogin-1 genes in denervated tibialis anterior (TA) muscle of Wistar rats. Five groups were examined: (1) denervated (D); (2) D+ES; (3) sham denervation; (4) normal (N); and (5) N+ES. Twenty muscle contractions were stimulated every 48 h using surface electrodes. After 28 days, ES significantly decreased the expression of myoD and atrogin-1 in D+ES compared to the D group. However, ES did not prevent muscle-fiber atrophy after denervation. Thus, ES based on chronaxie values and applied to denervated muscles using surface electrodes, as normally used in human rehabilitation, was able to reduce the myoD and atrogin-1 gene expressions, which are related to muscular growth and atrophy, respectively. The results of this study provide new information for the treatment of denervated skeletal muscle using surface ES.
authors.affiliation: Department of Physical Therapy, Federal University of São Carlos, Rodovia Washington Luís, Km 235, CEP: 13565-905, São Carlos, São Paulo, Brazil.
authors.forename: Thiago Luiz
authors.initials: TL
authors.lastname: Russo
authors.forename: Sabrina Messa
authors.initials: SM
authors.lastname: Peviani
authors.forename: Camila Marques
authors.initials: CM
authors.lastname: Freria
authors.forename: Davilene
authors.initials: D
authors.lastname: Gigo-Benato
authors.forename: Stefano
authors.initials: S
authors.lastname: Geuna
authors.forename: Tania Fátima
authors.initials: TF
authors.lastname: Salvini
mesh_terms: D000818:Animals; D049108:Cell Enlargement; D002907:Chronaxy / Q000502:physiology*; D004195:Disease Models, Animal; D015536:Down-Regulation / Q000502:physiology; D004599:Electric Stimulation Therapy / Q000379:methods; D005786:Gene Expression Regulation / Q000502:physiology; D008297:Male; D009119:Muscle Contraction / Q000502:physiology; D009121:Muscle Denervation; D018485:Muscle Fibers, Skeletal / Q000378:metabolism / Q000473:pathology; D009124:Muscle Proteins / Q000235:genetics*; D018482:Muscle, Skeletal / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology; D009133:Muscular Atrophy / Q000235:genetics / Q000378:metabolism* / Q000628:therapy*; D017570:MyoD Protein / Q000235:genetics*; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D044843:SKP Cullin F-Box Protein Ligases / Q000235:genetics*; D020426:Sciatic Neuropathy / Q000503:physiopathology; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D009124:Muscle Proteins; D017570:MyoD Protein; C057363:MyoD1 myogenic differentiation protein; D012333:RNA, Messenger; C486692:Fbxo32 protein, rat; D044843:SKP Cullin F-Box Protein Ligases