Hexokinase 2, Glycogen Synthase and Phosphorylase Play a Key Role in Muscle Glycogen Supercompensation

Background: Glycogen-depleting exercise can lead to supercompensation of muscle glycogen stores, but the biochemical mechanisms of this phenomenon are still not completely understood. Methods: Using chronic low-frequency stimulation (CLFS) as an exercise model, the tibialis anterior muscle of rabbit...

Descripción completa

Detalles Bibliográficos
Autores: Irimia, José M., Rovira Juárez, Jordi, Nielsen, Jakob N., Guerrero, Mario, Wojtaszewski, Jorgen F. P., Cussó Fresquet, M. Roser
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2012
País:España
Institución:Universidad de Barcelona
Repositorio:Dipòsit Digital de la UB
OAI Identifier:oai:diposit.ub.edu:2445/43523
Acceso en línea:https://hdl.handle.net/2445/43523
Access Level:acceso abierto
Palabra clave:Glicogen
Glucòlisi
Múscul llis
Glycogen
Glycolysis
Smooth muscle
id ES_680fa4ab05abf272a67d27ed9c95734b
oai_identifier_str oai:diposit.ub.edu:2445/43523
network_acronym_str ES
network_name_str España
repository_id_str
spelling Hexokinase 2, Glycogen Synthase and Phosphorylase Play a Key Role in Muscle Glycogen SupercompensationIrimia, José M.Rovira Juárez, JordiNielsen, Jakob N.Guerrero, MarioWojtaszewski, Jorgen F. P.Cussó Fresquet, M. RoserGlicogenGlucòlisiMúscul llisGlycogenGlycolysisSmooth muscleBackground: Glycogen-depleting exercise can lead to supercompensation of muscle glycogen stores, but the biochemical mechanisms of this phenomenon are still not completely understood. Methods: Using chronic low-frequency stimulation (CLFS) as an exercise model, the tibialis anterior muscle of rabbits was stimulated for either 1 or 24 hours, inducing a reduction in glycogen of 90% and 50% respectively. Glycogen recovery was subsequently monitored during 24 hours of rest. Results: In muscles stimulated for 1 hour, glycogen recovered basal levels during the rest period. However, in those stimulated for 24 hours, glycogen was supercompensated and its levels remained 50% higher than basal levels after 6 hours of rest, although the newly synthesized glycogen had fewer branches. This increase in glycogen correlated with an increase in hexokinase-2 expression and activity, a reduction in the glycogen phosphorylase activity ratio and an increase in the glycogen synthase activity ratio, due to dephosphorylation of site 3a, even in the presence of elevated glycogen stores. During supercompensation there was also an increase in 59-AMP-activated protein kinase phosphorylation, correlating with a stable reduction in ATP and total purine nucleotide levels. Conclusions: Glycogen supercompensation requires a coordinated chain of events at two levels in the context of decreased cell energy balance: First, an increase in the glucose phosphorylation capacity of the muscle and secondly, control of the enzymes directly involved in the synthesis and degradation of the glycogen molecule. However, supercompensated glycogen has fewer branches.Public Library of Science (PLoS)2012info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionapplication/pdfhttps://hdl.handle.net/2445/43523Articles publicats en revistes (Ciències Fisiològiques)reponame:Dipòsit Digital de la UBinstname:Universidad de BarcelonaInglésReproducció del document publicat a: http://dx.doi.org/10.1371/journal.pone.0042453PLoS One, 2012, vol. 7, num. 7, p. e42453http://dx.doi.org/10.1371/journal.pone.0042453cc-by (c) Irimia, JM. et al., 2012http://creativecommons.org/licenses/by/3.0/esinfo:eu-repo/semantics/openAccessoai:diposit.ub.edu:2445/435232026-05-27T06:46:51Z
dc.title.none.fl_str_mv Hexokinase 2, Glycogen Synthase and Phosphorylase Play a Key Role in Muscle Glycogen Supercompensation
title Hexokinase 2, Glycogen Synthase and Phosphorylase Play a Key Role in Muscle Glycogen Supercompensation
spellingShingle Hexokinase 2, Glycogen Synthase and Phosphorylase Play a Key Role in Muscle Glycogen Supercompensation
Irimia, José M.
Glicogen
Glucòlisi
Múscul llis
Glycogen
Glycolysis
Smooth muscle
title_short Hexokinase 2, Glycogen Synthase and Phosphorylase Play a Key Role in Muscle Glycogen Supercompensation
title_full Hexokinase 2, Glycogen Synthase and Phosphorylase Play a Key Role in Muscle Glycogen Supercompensation
title_fullStr Hexokinase 2, Glycogen Synthase and Phosphorylase Play a Key Role in Muscle Glycogen Supercompensation
title_full_unstemmed Hexokinase 2, Glycogen Synthase and Phosphorylase Play a Key Role in Muscle Glycogen Supercompensation
title_sort Hexokinase 2, Glycogen Synthase and Phosphorylase Play a Key Role in Muscle Glycogen Supercompensation
dc.creator.none.fl_str_mv Irimia, José M.
Rovira Juárez, Jordi
Nielsen, Jakob N.
Guerrero, Mario
Wojtaszewski, Jorgen F. P.
Cussó Fresquet, M. Roser
author Irimia, José M.
author_facet Irimia, José M.
Rovira Juárez, Jordi
Nielsen, Jakob N.
Guerrero, Mario
Wojtaszewski, Jorgen F. P.
Cussó Fresquet, M. Roser
author_role author
author2 Rovira Juárez, Jordi
Nielsen, Jakob N.
Guerrero, Mario
Wojtaszewski, Jorgen F. P.
Cussó Fresquet, M. Roser
author2_role author
author
author
author
author
dc.subject.none.fl_str_mv Glicogen
Glucòlisi
Múscul llis
Glycogen
Glycolysis
Smooth muscle
topic Glicogen
Glucòlisi
Múscul llis
Glycogen
Glycolysis
Smooth muscle
description Background: Glycogen-depleting exercise can lead to supercompensation of muscle glycogen stores, but the biochemical mechanisms of this phenomenon are still not completely understood. Methods: Using chronic low-frequency stimulation (CLFS) as an exercise model, the tibialis anterior muscle of rabbits was stimulated for either 1 or 24 hours, inducing a reduction in glycogen of 90% and 50% respectively. Glycogen recovery was subsequently monitored during 24 hours of rest. Results: In muscles stimulated for 1 hour, glycogen recovered basal levels during the rest period. However, in those stimulated for 24 hours, glycogen was supercompensated and its levels remained 50% higher than basal levels after 6 hours of rest, although the newly synthesized glycogen had fewer branches. This increase in glycogen correlated with an increase in hexokinase-2 expression and activity, a reduction in the glycogen phosphorylase activity ratio and an increase in the glycogen synthase activity ratio, due to dephosphorylation of site 3a, even in the presence of elevated glycogen stores. During supercompensation there was also an increase in 59-AMP-activated protein kinase phosphorylation, correlating with a stable reduction in ATP and total purine nucleotide levels. Conclusions: Glycogen supercompensation requires a coordinated chain of events at two levels in the context of decreased cell energy balance: First, an increase in the glucose phosphorylation capacity of the muscle and secondly, control of the enzymes directly involved in the synthesis and degradation of the glycogen molecule. However, supercompensated glycogen has fewer branches.
publishDate 2012
dc.date.none.fl_str_mv 2012
dc.type.none.fl_str_mv info:eu-repo/semantics/article
info:eu-repo/semantics/publishedVersion
format article
status_str publishedVersion
dc.identifier.none.fl_str_mv https://hdl.handle.net/2445/43523
url https://hdl.handle.net/2445/43523
dc.language.none.fl_str_mv Inglés
language_invalid_str_mv Inglés
dc.relation.none.fl_str_mv Reproducció del document publicat a: http://dx.doi.org/10.1371/journal.pone.0042453
PLoS One, 2012, vol. 7, num. 7, p. e42453
http://dx.doi.org/10.1371/journal.pone.0042453
dc.rights.none.fl_str_mv cc-by (c) Irimia, JM. et al., 2012
http://creativecommons.org/licenses/by/3.0/es
info:eu-repo/semantics/openAccess
rights_invalid_str_mv cc-by (c) Irimia, JM. et al., 2012
http://creativecommons.org/licenses/by/3.0/es
eu_rights_str_mv openAccess
dc.format.none.fl_str_mv application/pdf
dc.publisher.none.fl_str_mv Public Library of Science (PLoS)
publisher.none.fl_str_mv Public Library of Science (PLoS)
dc.source.none.fl_str_mv Articles publicats en revistes (Ciències Fisiològiques)
reponame:Dipòsit Digital de la UB
instname:Universidad de Barcelona
instname_str Universidad de Barcelona
reponame_str Dipòsit Digital de la UB
collection Dipòsit Digital de la UB
repository.name.fl_str_mv
repository.mail.fl_str_mv
_version_ 1869409934107475968
score 15,300724

Similares en LA Referencia