title: Comparison among the lipogenic potential of various substrates in rat hepatocytes: the differential effects of fructose-containing diets on hepatic lipogenesis.
abstract: Fructose feeding has been reported to cause hypertriglyceridemia in rats. Apparently this is due to increased hepatic fatty acid synthesis. In hepatocytes from female rats fed a 60% sucrose or fructose diet, the rate of lipogenesis was two times higher than in cells from rats fed a 60% glucose diet and three times higher than in cells from rats fed a commercial nonpurified diet. In hepatocytes from rats fed the fructose-containing diets, lactate was a better substrate than either butyrate or acetate, whereas in cells from rats fed either the glucose diet or the non-purified diet, butyrate was the best lipogenic substrate, and the lipogenic potential of lactate and acetate was similar. In all cases, 1 mM fructose caused a 30-40% stimulation of lipogenesis, while 10 mM glucose did not enhance fat synthesis above the endogenous rates. These results suggest that the differential effect of fructose-containing diets on hepatic lipogenesis results from activation of pyruvate dehydrogenase, thereby increasing the efficiency by which lactate is used as a carbon source for fatty acid synthesis. The differences in lipogenic potential of the various substrates tested is discussed.
authors: Department of Physiological Sciences, School of Veterinary Medicine, University of California, Davis 95616.
authors: A
authors: A
authors: Carmona
authors: R A
authors: RA
authors: Freedland
mesh_terms: D000818:Animals; D004040:Dietary Carbohydrates / Q000494:pharmacology; D005227:Fatty Acids / Q000096:biosynthesis*; D005260:Female; D005632:Fructose / Q000494:pharmacology*; D008099:Liver / Q000187:drug effects / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D013261:Sterols / Q000096:biosynthesis*
chemical_list: D004040:Dietary Carbohydrates; D005227:Fatty Acids; D013261:Sterols; D005632:Fructose