A fructose-rich diet decreases insulin-stimulated glucose incorporation into lipids but not glucose transport in adipocytes of normal and diabetic rats.
To study the cellular mechanisms underlying fructose-induced insulin resistance in rats, the effects of fructose feeding on insulin-stimulated glucose transport, oxidation and incorporation into lipids in epididymal adipocytes were evaluated in 27 normal and 27 noninsulin-dependent diabetic male Sprague-Dawley rats. Diabetes was induced by streptozotocin injection 2 d after birth. At 5 wk of age, both normal and diabetic rats were fed a diet containing 62% carbohydrate as fructose, dextrose or cornstarch. Fructose feeding for 6 wk induced glucose intolerance in normal rats (P < 0.05) and aggravated that of diabetic rats (P < 0.05). Plasma triacylglycerol concentration was higher in fructose-fed than in starch-fed or dextrose-fed rats (P < 0.05). Adipocytes of fructose-fed rats had significantly lower maximum insulin-stimulated glucose incorporation into total lipids than those of rats fed starch, and tended (P = 0.22) to have lower production of CO2 from glucose than adipocytes of the other dietary groups. Glucose transport in adipocytes of dextrose-, starch- and fructose-fed rats did not differ. We conclude that in both normal and diabetic rats, a chronic fructose-rich diet induced hypertriacylglycerolemia, glucose intolerance and insulin resistance of adipocytes.
Luo
J
J
Department of Diabetes, INSERM U 341, Paris, France.
Rizkalla
S W
SW
Lerer-Metzger
M
M
Boillot
J
J
Ardeleanu
A
A
Bruzzo
F
F
Chevalier
A
A
Slama
G
G
D017667:Adipocytes / Q000166:cytology / Q000378:metabolism*; D000818:Animals; D001692:Biological Transport / Q000502:physiology; D001786:Blood Glucose / Q000032:analysis; D001835:Body Weight / Q000502:physiology; D002245:Carbon Dioxide / Q000378:metabolism; D002478:Cells, Cultured; D003921:Diabetes Mellitus, Experimental / Q000378:metabolism* / Q000473:pathology; D003924:Diabetes Mellitus, Type 2 / Q000378:metabolism* / Q000473:pathology; D004040:Dietary Carbohydrates / Q000097:blood / Q000494:pharmacology*; D004435:Eating / Q000502:physiology; D005632:Fructose / Q000097:blood / Q000494:pharmacology*; D005947:Glucose / Q000378:metabolism* / Q000493:pharmacokinetics; D005951:Glucose Tolerance Test; D007328:Insulin / Q000097:blood / Q000502:physiology; D050356:Lipid Metabolism; D008297:Male; D009929:Organ Size / Q000502:physiology; D010084:Oxidation-Reduction; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D013311:Streptozocin
D001786:Blood Glucose; D004040:Dietary Carbohydrates; D007328:Insulin; D002245:Carbon Dioxide; D005632:Fructose; D013311:Streptozocin; D005947:Glucose