Effect of ethanol on the metabolism of primary astrocytes studied by (13)C- and (31)P-NMR spectroscopy.
Nuclear magnetic resonance was used as the primary technique to investigate the effect of ethanol (40, 80, and 160 mM) on the levels of high-energy phosphates, glycolytic flux, anaplerotic and oxidative fluxes to the tricarboxylic acid (TCA) cycle, the contribution of the pentose phosphate pathway (PPP), and the uptake and release of amino acids on primary cultures of rat astrocytes. On line (31)P-NMR spectroscopy showed that long-term exposure to ethanol caused a drop in the levels of ATP and phosphocreatine. The ratio between the fluxes through the pyruvate dehydrogenase and pyruvate carboxylase reactions also decreased, whereas the glycolytic flux and the ratio between formation of lactate and glucose consumption increased when cells were exposed to acute doses of ethanol. Flux through the pentose phosphate pathway was not affected. The uptake of cysteine and the release of glutamine were stimulated by ethanol, whereas the release of methionine was inhibited. Moreover, the fractional enrichment in serine was enhanced. The changes in the amino acid metabolism are interpreted as a response to oxidative stress induced by ethanol.
Fonseca
L L
LL
Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Rua de Quinta Grande, 6, 2780-156 Oeiras, Portugal.
Alves
P M
PM
Carrondo
M J
MJ
Santos
H
H
D000227:Adenine Nucleotides / Q000378:metabolism; D020268:Alcohol-Induced Disorders, Nervous System / Q000378:metabolism* / Q000503:physiopathology; D000596:Amino Acids / Q000187:drug effects / Q000378:metabolism; D000818:Animals; D000831:Animals, Newborn; D001253:Astrocytes / Q000000981:diagnostic imaging / Q000187:drug effects*; D001921:Brain / Q000000981:diagnostic imaging / Q000187:drug effects*; D002250:Carbon Radioisotopes / Q000493:pharmacokinetics; D002478:Cells, Cultured; D002952:Citric Acid Cycle / Q000187:drug effects / Q000502:physiology; D004305:Dose-Response Relationship, Drug; D004734:Energy Metabolism / Q000187:drug effects* / Q000502:physiology; D000431:Ethanol / Q000378:metabolism / Q000493:pharmacokinetics*; D006019:Glycolysis / Q000187:drug effects / Q000502:physiology; D009682:Magnetic Resonance Spectroscopy; D010085:Oxidative Phosphorylation / Q000187:drug effects; D010101:Oxygen Consumption / Q000187:drug effects / Q000502:physiology; D010427:Pentose Phosphate Pathway / Q000187:drug effects / Q000502:physiology; D010761:Phosphorus Radioisotopes / Q000493:pharmacokinetics; D011766:Pyruvate Carboxylase / Q000187:drug effects / Q000378:metabolism; D011768:Pyruvate Dehydrogenase Complex / Q000187:drug effects / Q000378:metabolism; D011877:Radionuclide Imaging; D051381:Rats; D017208:Rats, Wistar
D000227:Adenine Nucleotides; D000596:Amino Acids; D002250:Carbon Radioisotopes; D010761:Phosphorus Radioisotopes; D011768:Pyruvate Dehydrogenase Complex; D000431:Ethanol; D011766:Pyruvate Carboxylase