Metabolism of 2,3-butanediol stereoisomers in the perfused rat liver.
The identification of 2,3-butanediol in sera of alcoholics led to the hypothesis that it may be a specific marker of alcohol abuse. We have investigated the metabolism of the individual isomers of 2,3-butanediol (2R,3R-, 2S,3S-, meso-2,3-butanediol and racemic 2,3-butanediol) in perfused livers from fed rats. Rates of uptake of the isomers decrease in the order (i) 2R,3R-, (ii) meso-, (iii) 2S,3S-2,3-butanediol. We observed interconversion of isomers and oxidation to acetoin with 2R,3R- and meso- but not with 2S,3S-2,3-butanediol. In perfusions conducted in deuterium oxide, interconversion of isomers was accompanied by incorporation of deuterium. Thus, interconversion of isomers occurs via a reversible oxidation to acetoin with incorporation of hydrogen from water. In perfusions with either 2R,3R- or meso-[2-14C]2,3-butanediol, the substrates were converted to labeled acetate, R-3-hydroxybutyrate and CO2, suggesting that 2,3-butanediol is oxidized to acetyl-CoA via acetoin.
Department of Nutrition, University of Montreal, Quebec, Canada.
J A
JA
Montgomery
F
F
David
M
M
Garneau
H
H
Brunengraber
D020155:3-Hydroxybutyric Acid; D000085:Acetates / Q000378:metabolism; D000093:Acetoin / Q000378:metabolism; D000818:Animals; D001692:Biological Transport; D002072:Butylene Glycols / Q000378:metabolism*; D002250:Carbon Radioisotopes; D006885:Hydroxybutyrates / Q000378:metabolism; D008099:Liver / Q000378:metabolism*; D008297:Male; D010477:Perfusion; D011865:Radioisotope Dilution Technique; D051381:Rats; D017207:Rats, Sprague-Dawley; D013237:Stereoisomerism; D013997:Time Factors
D000085:Acetates; D002072:Butylene Glycols; D002250:Carbon Radioisotopes; D006885:Hydroxybutyrates; C026978:2,3-butylene glycol; D000093:Acetoin; D020155:3-Hydroxybutyric Acid