Dysfunctions of cellular oxidative metabolism in patients with mutations in the NDUFS1 and NDUFS4 genes of complex I.

TitleDysfunctions of cellular oxidative metabolism in patients with mutations in the NDUFS1 and NDUFS4 genes of complex I.
Publication TypeJournal Article
Year of Publication2006
AuthorsIuso, A, Scacco, S, Piccoli, C, Bellomo, F, Petruzzella, V, Trentadue, R, Minuto, M, Ripoli, M, Capitanio, N, Zeviani, M, Papa, S
JournalJ Biol Chem
Volume281
Issue15
Pagination10374-80
Date Published2006 Apr 14
ISSN0021-9258
KeywordsAdenosine Triphosphate, Antioxidants, Catalysis, Cell Line, Cell Respiration, Codon, Nonsense, Cyclic AMP, Electron Transport, Electron Transport Complex I, Electrophoresis, Gel, Two-Dimensional, Electrophoresis, Polyacrylamide Gel, Fibroblasts, Glutathione, Homozygote, Humans, Hydrogen Peroxide, Kinetics, Membrane Potentials, Microscopy, Confocal, Mitochondria, Mutation, NADH Dehydrogenase, NADH, NADPH Oxidoreductases, Oxygen, Reactive Oxygen Species, Reverse Transcriptase Polymerase Chain Reaction, Transcription, Genetic
Abstract

The pathogenic mechanism of a G44A nonsense mutation in the NDUFS4 gene and a C1564A mutation in the NDUFS1 gene of respiratory chain complex I was investigated in fibroblasts from human patients. As previously observed the NDUFS4 mutation prevented complete assembly of the complex and caused full suppression of the activity. The mutation (Q522K replacement) in NDUFS1 gene, coding for the 75-kDa Fe-S subunit of the complex, was associated with (a) reduced level of the mature complex, (b) marked, albeit not complete, inhibition of the activity, (c) accumulation of H(2)O(2) and O(2)(.-) in mitochondria, (d) decreased cellular content of glutathione, (e) enhanced expression and activity of glutathione peroxidase, and (f) decrease of the mitochondrial potential and enhanced mitochondrial susceptibility to reactive oxygen species (ROS) damage. No ROS increase was observed in the NDUFS4 mutation. Exposure of the NDUFS1 mutant fibroblasts to dibutyryl-cAMP stimulated the residual NADH-ubiquinone oxidoreductase activity, induced disappearance of ROS, and restored the mitochondrial potential. These are relevant observations for a possible therapeutical strategy in NDUFS1 mutant patients.

DOI10.1074/jbc.M513387200
Alternate JournalJ. Biol. Chem.
Citation Key10.1074/jbc.M513387200
PubMed ID16478720