Effect of eccentric exercise velocity on akt/mtor/p70(s6k) signaling in human skeletal muscle

Autor(es):Mostrar menos -

Roschel, Hamilton ^{[1, 2]} ; Ugrinowistch, Carlos ^[1] ; Barroso, Renato ^[1] ; Batista, Mauro A. B. ^[1] ; Souza, Eduardo O. ^[1] ; Aoki, Marcelo S. ^[1] ; Siqueira-Filho, Mario A. ^[3] ; Zanuto, Ricardo ^[3] ; Carvalho, Carla R. O. ^[3] ; Neves, Jr., Manoel ^[2] ; Mello, Marco T. ^[4] ; Tricoli, Valmor ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Sch Phys Educ & Sport, BR-05508 Sao Paulo - Brazil

^[2] Univ Sao Paulo, Sch Med, BR-05508 Sao Paulo - Brazil

^[3] Univ Sao Paulo, Inst Biomed Sci, BR-05508 Sao Paulo - Brazil

^[4] Univ Fed Sao Paulo, Sao Paulo - Brazil

• Tipo de documento: Artigo Científico
• Fonte: APPLIED PHYSIOLOGY NUTRITION AND METABOLISM; v. 36, n. 2, p. 283-290, APR 2011.
• Citações Web of Science: 12

Resumo

It has been suggested that muscle tension plays a major role in the activation of intracellular pathways for skeletal muscle hypertrophy via an increase in mechano growth factor (MGF) and other downstream targets. Eccentric exercise (EE) imposes a greater amount of tension on the active muscle. In particular, high-speed EE seems to exert an additional effect on muscle tension and, thus, on muscle hypertrophy. However, little is known about the effect of EE velocity on hypertrophy signaling. This study investigated the effect of acute EE-velocity manipulation on the Akt/mTORCI/p70(S6K) hypertrophy pathway. Twenty subjects were assigned to either a slow (20 degrees.s(-1); ES) or fast EE (210 degrees.s(-1); EF) group. Biopsies were taken from vastus lateralis at baseline (B), immediately after (T1), and 2 h after (T2) the completion of 5 sets of 8 repetitions of eccentric knee extensions. Akt, mTOR, and p70(S6K) total protein were similar between groups, and did not change postintervention. Further, Akt and p70(S6K) protein phosphorylation were higher at T2 than at B for ES and EF. MGF messenger RNA was similar between groups, and only significantly higher at T2 than at B in ES. The acute manipulation of EE velocity does not seem to differently influence intracellular hypertrophy signaling through the Akt/mTORCI/p70S6K pathway. (AU)

• Processo FAPESP: 10/51428-2 - Efeitos do treinamento de força associado à oclusão vascular em pacientes com osteoartrite de joelho: um estudo clínico controlado
• Beneficiário: Hamilton Augusto Roschel da Silva
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado