Fatty acid synthesis and generation of glycerol-3-phosphate in brown adipose tissue from rats fed a cafeteria diet
Contribuinte(s) |
UNIVERSIDADE DE SÃO PAULO |
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Data(s) |
19/10/2012
19/10/2012
2008
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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 |
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 |