title: The β2-adrenoceptor agonist formoterol improves structural and functional regenerative capacity of skeletal muscles from aged rat at the early stages of postinjury.
abstract: Skeletal muscles from old rats fail to completely regenerate following injury. This study investigated whether pharmacological stimulation of β2-adrenoceptors in aged muscles following injury could improve their regenerative capacity, focusing on myofiber size recovery. Young and aged rats were treated with a subcutaneous injection of β2-adrenergic agonist formoterol (2 μg/kg/d) up to 10 and 21 days after soleus muscle injury. Formoterol-treated muscles from old rats evaluated at 10 and 21 days postinjury showed reduced inflammation and connective tissue but a similar number of regenerating myofibers of greater caliber when compared with their injured controls. Formoterol minimized the decrease in tetanic force and increased protein synthesis and mammalian target of rapamycin phosphorylation in old muscles at 10 days postinjury. Our results suggest that formoterol improves structural and functional regenerative capacity of regenerating skeletal muscles from aged rats by increasing protein synthesis via mammalian target of rapamycin activation. Furthermore, formoterol may have therapeutic benefits in recovery following muscle damage in senescent individuals.
authors: Department of Anatomy, Institute of Biomedical Sciences, University of Sao Paulo, São Paulo, Brazil.
authors: Talita C
authors: TC
authors: Conte
authors: Lucila H
authors: LH
authors: Silva
authors: Meiricris T
authors: MT
authors: Silva
authors: Sandro M
authors: SM
authors: Hirabara
authors: Antonio C
authors: AC
authors: Oliveira
authors: Rui
authors: R
authors: Curi
authors: Anselmo S
authors: AS
authors: Moriscot
authors: Marcelo S
authors: MS
authors: Aoki
authors: Elen H
authors: EH
authors: Miyabara
mesh_terms: D000367:Age Factors; D000704:Analysis of Variance; D000818:Animals; D015153:Blotting, Western; D000242:Cyclic AMP / Q000378:metabolism; D004983:Ethanolamines / Q000008:administration & dosage / Q000494:pharmacology*; D000068759:Formoterol Fumarate; D008297:Male; D009119:Muscle Contraction / Q000502:physiology; D018482:Muscle, Skeletal / Q000187:drug effects* / Q000378:metabolism / Q000503:physiopathology; D010766:Phosphorylation; D051381:Rats; D017208:Rats, Wistar; D012038:Regeneration / Q000187:drug effects*; D018709:Statistics, Nonparametric; D058570:TOR Serine-Threonine Kinases / Q000378:metabolism
chemical_list: D004983:Ethanolamines; D000242:Cyclic AMP; D058570:TOR Serine-Threonine Kinases; D000068759:Formoterol Fumarate