Abstract |
We report severe coenzyme Q10 deficiency of muscle in a 4-year-old boy presenting with progressive muscle weakness, seizures, cerebellar syndrome, and a raised cerebro-spinal fluid lactate concentration. State-3 respiratory rates of muscle mitochondria with glutamate, pyruvate, palmitoylcarnitine, and succinate as respiratory substrates were markedly reduced, whereas ascorbate/N,N,N',N'- tetramethyl-p-phenylenediamine were oxidized normally. The activities of complexes I, II, III and IV of the electron transport chain were normal, but the activities of complexes I+III and II+III, both systems requiring coenzyme Q10 as an electron carrier, were dramatically decreased. These results suggested a defect in the mitochondrial coenzyme Q10 content. This was confirmed by the direct assessment of coenzyme Q10 level by high-performance liquid chromatography in patient's muscle homogenate and isolated mitochondria, revealing levels of 16% and 6% of the control values, respectively. We did not find any impairment of the respiratory chain either in a lymphoblastoid cell line or in skin cultured fibroblasts from the patient, suggesting that the coenzyme Q10 depletion was tissue-specific. This is a new case of a muscle deficiency of mitochondrial coenzyme Q in a patient suffering from an encephalomyopathy.
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Authors | E Boitier, F Degoul, I Desguerre, C Charpentier, D François, G Ponsot, M Diry, P Rustin, C Marsac |
Journal | Journal of the neurological sciences
(J Neurol Sci)
Vol. 156
Issue 1
Pg. 41-6
( 1998)
ISSN: 0022-510X [Print] Netherlands |
PMID | 9559985
(Publication Type: Case Reports, Journal Article, Research Support, Non-U.S. Gov't)
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Chemical References |
- Coenzymes
- Ubiquinone
- Lactic Acid
- coenzyme Q10
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Topics |
- Cerebellar Ataxia
(complications)
- Child, Preschool
- Coenzymes
- Electron Transport
- Epilepsy
(complications)
- Humans
- Kinetics
- Lactic Acid
(cerebrospinal fluid)
- Male
- Mitochondria, Muscle
(pathology)
- Mitochondrial Encephalomyopathies
(cerebrospinal fluid, complications, physiopathology)
- Muscle, Skeletal
(physiopathology)
- Polarography
- Retinal Diseases
(complications)
- Ubiquinone
(analogs & derivatives, physiology)
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