| First Author | Amaral AU | Year | 2012 |
| Journal | Mol Genet Metab | Volume | 107 |
| Issue | 3 | Pages | 375-82 |
| PubMed ID | 22999741 | Mgi Jnum | J:190093 |
| Mgi Id | MGI:5448069 | Doi | 10.1016/j.ymgme.2012.08.016 |
| Citation | Amaral AU, et al. (2012) Reduction of Na+, K+-ATPase activity and expression in cerebral cortex of glutaryl-CoA dehydrogenase deficient mice: a possible mechanism for brain injury in glutaric aciduria type I. Mol Genet Metab 107(3):375-82 |
| abstractText | Mitochondrial dysfunction has been proposed to play an important role in the neuropathology of glutaric acidemia type I (GA I). However, the relevance of bioenergetics disruption and the exact mechanisms responsible for the cortical leukodystrophy and the striatum degeneration presented by GA I patients are not yet fully understood. Therefore, in the present work we measured the respiratory chain complexes activities I-IV, mitochondrial respiratory parameters state 3, state 4, the respiratory control ratio and dinitrophenol (DNP)-stimulated respiration (uncoupled state), as well as the activities of alpha-ketoglutarate dehydrogenase (alpha-KGDH), creatine kinase (CK) and Na+, K+-ATPase in cerebral cortex, striatum and hippocampus from 30-day-old Gcdh-/- and wild type (WT) mice fed with a normal or a high Lys (4.7%) diet. When a baseline (0.9% Lys) diet was given, we verified mild alterations of the activities of some respiratory chain complexes in cerebral cortex and hippocampus, but not in striatum from Gcdh-/- mice as compared to WT animals. Furthermore, the mitochondrial respiratory parameters and the activities of alpha-KGDH and CK were not modified in all brain structures from Gcdh-/- mice. In contrast, we found a significant reduction of Na(+), K(+)-ATPase activity associated with a lower degree of its expression in cerebral cortex from Gcdh-/- mice. Furthermore, a high Lys (4.7%) diet did not accentuate the biochemical alterations observed in Gcdh-/- mice fed with a normal diet. Since Na(+), K(+)-ATPase activity is required for cell volume regulation and to maintain the membrane potential necessary for a normal neurotransmission, it is presumed that reduction of this enzyme activity may represent a potential underlying mechanism involved in the brain swelling and cortical abnormalities (cortical atrophy with leukodystrophy) observed in patients affected by GA I. |
