Glyceraldehyde metabolism in human erythrocytes in comparison with that of glucose and dihydroxyacetone.
Metabolism of D-glyceraldehyde in human erythrocytes in comparison with that of glucose and dihydroxyacetone was studied. Both trioses were metabolized to produce L-lactate at rates comparable to that of L-lactate formation from glucose. Almost complete inactivation of glyceraldehyde-3-phosphate dehydrogenase by treatment of cells with iodoacetate resulted in a 95% decrease in L-lactate formation from the ketotriose as well as from glucose, whereas L-lactate formation from the aldotriose was only partially reduced (60%). D-Lactate was produced faster from either the aldotriose or the ketotriose than from glucose, but the ability of the two trioses to produce D-lactate was far lower than that to produce L-lactate. Almost complete inhibition of aldehyde dehydrogenase by disulfiram and of both aldose reductase and aldehyde reductase II by sorbinil, had no effect on L-lactate formation from D-glyceraldehyde. The present study suggests that D-glyceraldehyde is metabolized via two or more pathways including the glycolytic pathway after its phosphorylation by triokinase, and that neither oxidation to D-glyceric acid nor reduction to glycerol is a prerequisite for D-glyceraldehyde metabolism.
Taguchi
Tadao
T
Department of Pathobiochemistry, Faculty of Pharmacy, Meijo University, Nagoya 468-8503, Japan.
Murase
Shigeki
S
Miwa
Ichitomo
I
D050260:Carbohydrate Metabolism; D004098:Dihydroxyacetone / Q000378:metabolism*; D004221:Disulfiram / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D004912:Erythrocytes / Q000378:metabolism*; D005947:Glucose / Q000378:metabolism*; D005985:Glyceraldehyde / Q000378:metabolism*; D024581:Glyceraldehyde-3-Phosphate Dehydrogenase (Phosphorylating) / Q000378:metabolism; D006019:Glycolysis; D006454:Hemoglobins / Q000378:metabolism; D006801:Humans; D007093:Imidazoles / Q000494:pharmacology; D048289:Imidazolidines; D007461:Iodoacetates / Q000494:pharmacology; D007773:Lactates / Q000378:metabolism
D004791:Enzyme Inhibitors; D006454:Hemoglobins; D007093:Imidazoles; D048289:Imidazolidines; D007461:Iodoacetates; D007773:Lactates; D005985:Glyceraldehyde; D024581:Glyceraldehyde-3-Phosphate Dehydrogenase (Phosphorylating); C026411:sorbinil; D005947:Glucose; D004098:Dihydroxyacetone; D004221:Disulfiram