Fatty acid synthesis and generation of glycerol-3-phosphate in brown adipose tissue from rats fed a cafeteria diet


Autoria(s): CHAVES, Valeria E.; FRASSON, Danubia; MARTINS-SANTOS, Maria E. S.; NAVEGANTES, Luiz C. C.; GALBAN, Victor D.; GAROFALO, Maria A. R.; KETTELHUT, Isis C.; MIGLIORINI, Renato H.
Contribuinte(s)

UNIVERSIDADE DE SÃO PAULO

Data(s)

19/10/2012

19/10/2012

2008

Resumo

In vivo fatty acid synthesis and the pathways of glycerol-3-phosphate (G3P) production were investigated in brown adipose tissue (BAT) from rats fed a cafeteria diet for 3 weeks. In spite of BAT activation, the diet promoted an increase in the carcass fatty acid content. Plasma insulin levels were markedly increased in cafeteria diet-fed rats. Two insulin-sensitive processes, in vivo fatty acid synthesis and in vivo glucose uptake (which was used to evaluate G3P generation via glycolysis) were increased in BAT from rats fed the cafeteria diet. Direct glycerol phosphorylation, evaluated by glycerokinase (GyK) activity and incorporation of [U-(14)C]glycerol into triacylglycerol (TAG)-glycerol, was also markedly increased in BAT from these rats. In contrast, the cafeteria diet induced a marked reduction of BAT glyceroneogenesis, evaluated by phosphoenolpyruvate carboxykinase-C activity and incorporation of [1-(14)C]pyruvate into TAG-glycerol. BAT denervation resulted in an approximately 50% reduction of GyK activity, but did not significantly affect BAT in vivo fatty acid synthesis, in vivo glucose uptake, or glyceroneogenesis. The data suggest that the supply of G3P for BAT TAG synthesis can be adjusted independently from the sympathetic nervous system and solely by reciprocal changes in the generation of G3P via glycolysis and via glyceroneogenesis, with no participation of direct phosphorylation of glycerol by GyK.

Identificador

CANADIAN JOURNAL OF PHYSIOLOGY AND PHARMACOLOGY, v.86, n.7, p.416-423, 2008

0008-4212

http://producao.usp.br/handle/BDPI/23793

10.1139/Y08-052

http://dx.doi.org/10.1139/Y08-052

Idioma(s)

eng

Publicador

CANADIAN SCIENCE PUBLISHING, NRC RESEARCH PRESS

Relação

Canadian Journal of Physiology and Pharmacology

Direitos

restrictedAccess

Copyright CANADIAN SCIENCE PUBLISHING, NRC RESEARCH PRESS

Palavras-Chave #phosphoenolpyruvate carboxykinase #glycerokinase #in vivo glucose uptake #TAG-glycerol synthesis #lipoprotein lipase #CARBOHYDRATE-FREE DIET #HIGH-PROTEIN DIET #PHOSPHOENOLPYRUVATE CARBOXYKINASE #GLUCOSE-UTILIZATION #COLD-EXPOSURE #GLYCERONEOGENESIS #TURNOVER #NOREPINEPHRINE #NORADRENALINE #GLYCEROKINASE #Pharmacology & Pharmacy #Physiology
Tipo

article

original article

publishedVersion