Oral L-glutamine pretreatment attenuates skeletal muscle atrophy induced by 24-h fasting in mice

de Vasconcelos D.A.A.; Giesbertz P.; de Souza D.R.; Vitzel K.F.; Abreu P.; MARZUCA-NASSR, G. N.;; Fortes M.A.S.; Murata G.M.; Hirabara S.M.; Curi R.; Daniel H.; Pithon-Curi T.C.

Abstract

L-Glutamine (L-Gln) supplementation has been pointed out as an anticatabolic intervention, but its effects on protein synthesis and degradation signaling in skeketal muscle are still poorly known. The effects of L-Gln pretreatment (1 g kg(-1) day(-1) body weight for 10 days) on muscle fiber cross-sectional area (CSA), amino acid composition (measured by LC-MS/MS) and protein synthesis (Akt-mTOR) and degradation (ubiquitin ligases) signaling in soleus and extensor digitorum longus (EDL) muscles in 24-h-fasted mice were investigated. The fiber CSA of EDL muscle was not different between the L-Gln-fasted and L-Gln-fed groups. This finding was associated with reduced contents of L-Leu and L-Iso and activation of protein synthesis signaling (p-RPS6Ser240/244 and Akt-mTOR). The spectrum of soleus muscle fiber CSA distribution was larger in L-Gln-fasted as compared with placebo-fasted mice. This effect of L-Gln pretreatment was associated with changes in red fibers L-Gln metabolism as indicated by increased intracellular L-glutamine/L-glutamate ratio, L-aspartate and GABA levels. L-Gln supplementation reduced fasting-induced mass loss in tibialis anterior and gastrocnemius muscles. Evidence is presented that pretreatment with L-glutamine attenuates skeletal muscle atrophy induced by 24-h fasting through mechanisms that vary with the muscle fiber type. (C) 2019 Elsevier Inc. All rights reserved.

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Título según WOS: Oral L-glutamine pretreatment attenuates skeletal muscle atrophy induced by 24-h fasting in mice
Título según SCOPUS: Oral L-glutamine pretreatment attenuates skeletal muscle atrophy induced by 24-h fasting in mice
Título de la Revista: JOURNAL OF NUTRITIONAL BIOCHEMISTRY
Volumen: 70
Editorial: Elsevier
Fecha de publicación: 2019
Página de inicio: 202
Página final: 214
Idioma: English
DOI:

10.1016/j.jnutbio.2019.05.010

Notas: ISI, SCOPUS