Dietary fish oil increases lipid mobilization but does not decrease lipid storage-related enzyme activities in adipose tissue of insulin-resistant, sucrose-fed rats.
Fish oil feeding has been shown to limit visceral fat accumulation in insulin-resistant rats. Our goal was to determine whether this finding is due to increased fat mobilization or decreased lipid storage. Adipocytes were isolated from rats fed for 3 wk a diet containing 57.5 g/100 g sucrose and 14 g/100 g lipids as either fish oil (SF) or a mixture of standard oils (SC); there was also a reference group (R). Substituting fish oil for standard oils protected rats from visceral fat hypertrophy, hypertriglyceridemia and hyperglycemia. The stimulation of lipolysis was greater in adipocytes isolated from SF-fed rats than in those from SC-fed rats. Fatty acid synthase (FAS) activity was markedly lower in the liver but not in the adipose tissues of rats fed SF. Lipoprotein lipase (LPL) activity was 2.2-fold higher in the adipose tissues but not in the muscle in rats fed the SF diet than in those fed the SC diet. The decrease in visceral fat in rats fed fish oil could be attributed to decreased plasma triacylglycerol concentration and/or increased lipid mobilization rather than to reduced lipid storage.
Peyron-Caso
Elodie
E
Department of Diabetes-INSERM U341, Hôtel-Dieu Hospital, 75004 Paris, France.
Quignard-Boulangé
Annie
A
Laromiguière
Muriel
M
Feing-Kwong-Chan
Sandrine
S
Véronèse
Annie
A
Ardouin
Bernadette
B
Slama
Gérard
G
Rizkalla
Salwa W
SW
D000273:Adipose Tissue / Q000187:drug effects* / Q000201:enzymology / Q000378:metabolism; D000818:Animals; D001835:Body Weight / Q000187:drug effects; D004042:Dietary Fats, Unsaturated / Q000494:pharmacology*; D064429:Fatty Acid Synthases / Q000378:metabolism; D005395:Fish Oils / Q000494:pharmacology*; D007545:Isoproterenol / Q000494:pharmacology; D050356:Lipid Metabolism; D008297:Male; D009929:Organ Size / Q000187:drug effects; D051381:Rats; D017207:Rats, Sprague-Dawley
D004042:Dietary Fats, Unsaturated; D005395:Fish Oils; D064429:Fatty Acid Synthases; D007545:Isoproterenol