Daytime restricted feeding modifies the daily variations of liver gluconeogenesis: Adaptations in biochemical and endocrine regulators
Por:
Perez-Mendoza, M, Rivera-Zavala, JB, Diaz-Munoz, M
Publicada:
1 ago 2014
Resumen:
Daytime restricted feeding (DRF) promotes circadian adaptations in the metabolic processing of nutrients. We explored the hepatic gluconeogenic response in DRF rats by the temporal profiles of the following: (1) the activity of glucose 6-phosphatase (G6Pase) and phosphoenolpyruvate carboxykinase (PEPCK), as well as the periportal and pericentral distribution of PEPCK; (2) conversion of alanine to glucose; (3) glycemia and liver glycogen content; (4) presence of glycogen synthase (GYS) and its phosphorylated form (at Ser641, pGYS); (5) circulating levels of corticosterone, glucagon and insulin; (6) glucose-tolerance test; and (7) sirtuin 1 (SIRT1) and peroxisome proliferator-activated receptor-coactivator 1a (PGC-1a). The results showed that DRF promoted: (1) a phase shift in G6Pase activity and an increase in PEPCK activity as well as a change of PEPCK from periportal to pericentral hepatocytes, (2) a net conversion of alanine to circulating glucose, (3) a decrease in glycemic values and a phase shift in the liver glycogen content, (4) a phase shift in GYS and an increase of pGYS, (5) an increase in the daily levels of corticosterone and glucagon, but a reduction in the levels of insulin, (6) normal glucose homeostasis in all groups and (7) an enhanced presence of SIRT1 and PGC-1a. It is proposed that the increased gluconeogenic in DRF group promotes synthesis of hepatic glycogen and the production of glucose. These results could be a modulation of the gluconeogenic process due to rheostatic adaptations in the endocrine, metabolic and timing regulation of liver and could be associated with the physiology of the food entrained oscillator. © 2014 Informa Healthcare USA, Inc.
Filiaciones:
Perez-Mendoza, M:
Univ Nacl Autonoma Mexico, Inst Neurobiol, Dept Neurobiol Celular & Mol, Queretaro, Qro, Mexico
Rivera-Zavala, JB:
Univ Nacl Autonoma Mexico, Inst Neurobiol, Dept Neurobiol Celular & Mol, Queretaro, Qro, Mexico
Diaz-Munoz, M:
Univ Nacl Autonoma Mexico, Inst Neurobiol, Dept Neurobiol Celular & Mol, Queretaro, Qro, Mexico
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