Metabolism of 13C-enriched D-fructose in hepatocytes from Goto-Kakizaki rats.
This study aims at assessing the conversion of exogenous D-[1-13C]fructose, D-[2-13C]fructose or D-[6-13C]-fructose (10 mM) to 13C-enriched and either hydrogenated or deuterated D-glucose, L-lactate and L-alanine released by rat liver cells prepared from Goto-Kakizaki rats and incubated for 120 min in the presence of unlabelled D-glucose (also 10 mM) and D2O. The results of this study are relevant to the relative contribution of fructokinase and hexokinase isoenzyme to the phosphorylation of D-fructose, the capacity of D-glucose to confer to glucokinase positive cooperativity towards D-fructose, the circulation of D-fructose 6-phosphate in the pentose phosphate pathway, the regulation of the cytosolic NADD/NADH ratio, the respective fate of D-fructose-derived D-glyceraldehyde and dihydroxyacetone phosphate, the deuteration of fructose-derived glycolytic intermediates at the phosphoglucoisomerase, phosphomannoisomerase, enolase, pyruvate kinase and glutamate-alanine transaminase levels, and the unequal generation of L-[1-13C]lactate by cells exposed to D-[1-13C]fructose or D-[6-13C]fructose versus D-[2-13C]-fructose.
Malaisse
Willy J
WJ
Laboratory of Experimental Hormonology, Brussels Free University, B-1070 Brussels, Belgium. malaisse@ulb.ac.be
Ladriere
Laurence
L
Verbruggen
Ingrid
I
Willem
Rudolph
R
D000409:Alanine / Q000378:metabolism; D000818:Animals; D002021:Buffers; D002247:Carbon Isotopes; D002478:Cells, Cultured; D003924:Diabetes Mellitus, Type 2 / Q000378:metabolism; D004195:Disease Models, Animal; D005632:Fructose / Q000737:chemistry / Q000378:metabolism*; D005947:Glucose / Q000378:metabolism; D022781:Hepatocytes / Q000378:metabolism*; D019344:Lactic Acid / Q000737:chemistry / Q000378:metabolism; D051381:Rats
D002021:Buffers; D002247:Carbon Isotopes; D005632:Fructose; D019344:Lactic Acid; D005947:Glucose; D000409:Alanine