Dietary (n-3) polyunsaturated fatty acids improve adipocyte insulin action and glucose metabolism in insulin-resistant rats: relation to membrane fatty acids.
To study the effects of dietary fish oil on insulin-stimulated glucose metabolism in adipocytes of insulin-resistant rats (rats fed 50% sucrose and 30% fat), eighteen 5-wk-old Sprague-Dawley rats were fed, for 6 wk, a diet containing 30% fat as either fish oil (FO) or a mixture of vegetable and animal oils [control oils (CO)]. A third reference group was fed a standard diet (62% corn starch and 13% fat). At the end of the 6-wk period, the two experimental groups had comparable plasma glucose concentrations that were higher than that found in the reference group. FO feeding corrected the hyperinsulinemia of the experimental rats (P < 0.05) to reach values in the reference group. Plasma triacylglycerol (P < 0.01) and cholesterol (P < 0.001) concentrations were also lower in rats fed FO than in those fed CO. The body weights of FO-fed rats were similar to that of CO-fed rats, but epididymal adipose tissue weight was lower (P < 0.01). Adipocytes of FO-fed rats, compared with those of CO-fed rats, had high insulin-stimulated glucose transport (P < 0.05), oxidation (P < 0.001) and incorporation into total lipids (P < 0.05). The incorporation of (n-3) polyunsaturated fatty acids in adipocyte membrane phospholipids was higher in FO-fed rats than in those fed CO (P < 0.0001). Insulin action was positively correlated with the fatty acid unsaturation index in membrane phospholipids. Thus dietary fish oil has beneficial effects on insulinemia, plasma lipids and insulin-stimulated glucose metabolism in insulin-resistant slightly diabetic rats.
Luo
J
J
Department of Diabetes, INSERM U341, University of Pierre et Marie Curie, Hôtel-Dieu Hospital, Paris, France.
Rizkalla
S W
SW
Boillot
J
J
Alamowitch
C
C
Chaib
H
H
Bruzzo
F
F
Desplanque
N
N
Dalix
A M
AM
Durand
G
G
Slama
G
G
D017667:Adipocytes / Q000187:drug effects / Q000378:metabolism* / Q000648:ultrastructure; D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D001835:Body Weight / Q000502:physiology; D002462:Cell Membrane / Q000737:chemistry / Q000378:metabolism / Q000502:physiology; D002784:Cholesterol / Q000097:blood; D004032:Diet / Q000662:veterinary; D004040:Dietary Carbohydrates / Q000494:pharmacology; D004041:Dietary Fats / Q000494:pharmacology; D004435:Eating / Q000502:physiology; D005227:Fatty Acids / Q000032:analysis* / Q000378:metabolism; D015525:Fatty Acids, Omega-3 / Q000378:metabolism / Q000494:pharmacology*; D005947:Glucose / Q000378:metabolism*; D007328:Insulin / Q000097:blood / Q000494:pharmacology*; D007333:Insulin Resistance / Q000502:physiology*; D050356:Lipid Metabolism; D008055:Lipids / Q000032:analysis / Q000097:blood; D008297:Male; D008563:Membrane Lipids / Q000032:analysis / Q000378:metabolism*; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D014280:Triglycerides / Q000097:blood
D001786:Blood Glucose; D004040:Dietary Carbohydrates; D004041:Dietary Fats; D005227:Fatty Acids; D015525:Fatty Acids, Omega-3; D007328:Insulin; D008055:Lipids; D008563:Membrane Lipids; D014280:Triglycerides; D002784:Cholesterol; D005947:Glucose