Resistance training regulates gene expression of molecules associated with intramyocellular lipids, glucose signaling and fiber size in old rats

Autor(es)

Teixeira Ribeiro, Manoel Benicio ; Guzzoni, Vinicius ; Hord, Jeffrey M. ; Lopes, Gisele Nunes ; Marqueti, Rita de Cassia ; de Andrade, Rosangela Vieira ; Selistre-de-Araujo, Heloisa Sobreiro ; Durigan, Joao Luiz Q.

• Tipo de documento: Artigo Científico
• Fonte: SCIENTIFIC REPORTS; v. 7, AUG 17 2017.
• Citações Web of Science: 6

Resumo

Sarcopenia is a complex multifactorial process, some of which involves fat infiltration. Intramyocellular lipid (IMCL) accumulation is postulated to play a role on sarcopenia during aging, which is believed to be due alterations in glucose homeostasis in the skeletal muscle. Sarcopenia, along with intramuscular lipids, is associated with physical inactivity. Resistance training (RT) has been indicated to minimize the age-induced muscle skeletal adaptations. Thus, we aimed to investigate the effects of RT on mRNA levels of regulatory components related to intramyocellular lipid, glucose metabolism and fiber size in soleus and gastrocnemius muscles of aged rats. Old male rats were submitted to RT (ladder climbing, progressive load, 3 times a week for 12 weeks). Age-induced accumulation of IMCL was attenuated by RT, which was linked to a PPARy-mediated mechanism, concomitant to enhanced regulatory components of glucose homeostasis (GLUT-4, G6PDH, Hk-2 and Gly-Syn-1). These responses were also linked to decreased catabolic (TNF-alpha, TWEAK/Fn14 axis; FOXO-1, Atrogin-1 and MuRF1; Myostatin) and increased anabolic intracellular pathways (IGF-1-mTOR-p70S6sk-1 axis; MyoD) in muscles of trained aged rats. Our results point out the importance of RT on modulation of gene expression of intracellular regulators related to age-induced morphological and metabolic adaptations in skeletal muscle. (AU)

• Processo FAPESP: 11/11229-3 - Matriz extracelular no envelhecimento e suas adaptações ao treinamento de força no tendão calcâneo de ratos: abordagem molecular, celular e biomecânica
• Beneficiário: Heloisa Sobreiro Selistre de Araújo
• Modalidade de apoio: Auxílio à Pesquisa - Regular