Sr. Blakely et al., DIETARY FRUCTOSE ALTERS THE INSULIN-LIKE EFFECTS OF DIETARY VANADATE IN ADIPOCYTES FROM RATS, Nutrition research, 15(1), 1995, pp. 25-35
In a chronic adaption feeding regimen, both D-fructose and vanadate in
dependently altered glucose oxidation and lipogenesis in adipose tissu
e of rats. This study investigated the acute feeding effects of vanada
te and D-fructose on these parameters in isolated rat adipocytes. In a
3-d fasting/refeeding regimen, male Wistar rats (10/group), weighing
150-200 g, were fed a diet containing either glucose (control) or fruc
tose at 27% (w/w) with sodium orthovanadate at 0, 25 (vanadate-l), and
50 (vanadate-2) mg/kg of diet. Neither body weight gain nor food effi
ciency differed statistically between treatment groups, but lower food
intake in vanadate-treated animals suggests a compensatory effect of
food efficiency in maintaining body weight gain at the same level as i
n other groups. Basal glucose oxidation to CO2 was enhanced in a dose-
related fashion in glucose-vanadate groups, but a significant interact
ion between fructose and vanadate led to a reduction in vanadate-induc
ed basal glucose oxidation. The reduction in basal and insulin-stimula
ted glucose conversion to lipid in adipocytes and in hepatic glucose 6
-phosphate dehydrogenase and malic enzyme activities by vanadate was n
ot altered by fructose. These results suggest that, under acute feedin
g, fructose alters the insulin-mimetic aspect of vanadate involving gl
ucose conversion to CO2 in isolated adipocytes.