A comparative study on lipogenesis from fructose and sucrose in rats
Hoshi, M.; Kikkawa, R.; Shreeve, W.W.
Medical Journal of Osaka University 25(3-4): 121-127
1975
ISSN/ISBN: 0030-6169 PMID: 1223605 Document Number: 89264
Male-Sprague-Dawley rats weighing about 250 g were fed initially on a pellet diet containing 56% starch and then on a diet with 77% glucose, fructose or sucrose. At the start and after 12 weeks on the high-sugar diet the rats were starved overnight and given by stomach tube 3 mu Ci of glucose-U-14C, fructose-U-14C or sucrose-U-14C, corresponding to the dietary order; the rats were killed 2 h after and the liver and blood were taken for lipid analysis. The incorporation of radioactivity from carbohydrates into triglyceride (TG) increased significantly in all diet groups at the end of the feeding period; that into diglyceride and free fatty acid (FFA) fractions from glucose fell, from sucrose rose, but was unchanged from fructose. There was no significant difference among the groups in liver TG and FFA, but plasma TG was highest with sucrose diet. With all carbohydrate diets a larger percentage of radioactivity was incorporated into TG-glycerol than into TG-FA and FFA fractions. Sucrose and fructose groups showed no significant difference in radioactivity in TG-glycerol fraction. The findings showed that sucrose in itself had lipogenic activity, besides its fructose component, probably by accelerating fatty acid synthesis.