Primary cultures of astrocytes from rat as a model for biotin deficiency in nervous tissue.
The activities and biotin-dependence of the three mitochondrial biotin-dependent carboxylases: pyruvate carboxylase, propionyl CoA carboxylase, and beta-methylcrotonyl CoA carboxylase of primary culture of astrocytes have been examined. An increase of the three mitochondrial carboxylase activities was observed during cell growth, as was the case for developing rat brain. Mitochondrial carboxylase activities from 3-wk-old primary cultures of astrocytes were higher than those in the neonatal rat brain. When astrocytes were grown in a 10% serum-enriched medium supplemented with avidin to bind biotin, the mitochondrial carboxylase activities were reduced to 15% of control value. Consistent with these results, after 3 wk in culture, the 3-hydroxyisovaleric acid concentration in the growth medium was tenfold higher than the controls. In this culture condition, cellular growth and the nonbiotin-dependent enzyme, glutamine synthetase, were not modified with respect to control. Primary cultures from newborn rat brain hemispheres are suggested as an experimental approach to the study of biotin deficiency in nervous tissue.
Rodríguez-Pombo
P
P
Centro de Biología Molecular, Facultad de Ciencias, Universidad Autonoma, Madrid, Spain.
Sweetman
L
L
Ugarte
M
M
D000818:Animals; D000831:Animals, Newborn; D001253:Astrocytes / Q000378:metabolism*; D001360:Avidin / Q000494:pharmacology; D001710:Biotin / Q000172:deficiency* / Q000494:pharmacology; D001921:Brain / Q000166:cytology; D019735:Carbon-Carbon Ligases; D002262:Carboxy-Lyases / Q000378:metabolism; D002478:Cells, Cultured; D008025:Ligases / Q000378:metabolism; D043586:Methylmalonyl-CoA Decarboxylase; D008928:Mitochondria / Q000201:enzymology*; D011766:Pyruvate Carboxylase / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D014631:Valerates / Q000378:metabolism
D014631:Valerates; D001360:Avidin; C004961:beta-hydroxyisovaleric acid; D001710:Biotin; D002262:Carboxy-Lyases; D008025:Ligases; D019735:Carbon-Carbon Ligases; D011766:Pyruvate Carboxylase; C021573:methylcrotonoyl-CoA carboxylase; D043586:Methylmalonyl-CoA Decarboxylase