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Assessment of Open Probability of the Mitochondrial Permeability Transition Pore in the Setting of Coenzyme Q Excess
Published on: June 1, 2022
Quinone-responsive multiple respiratory-chain dysfunction due to widespread coenzyme Q10 deficiency
A Rötig1, E L Appelkvist, V Geromel
1Unité de Recherches sur les Handicaps Génétiques de l'Enfant, INSERM U393, Hôpital des Enfants-Malades, Paris, France.
Lancet (London, England)
|September 6, 2000
Summary
Coenzyme Q10 deficiency, a rare mitochondrial disease, causes severe neurological and kidney issues. Early diagnosis and treatment with oral ubidecarenone (coenzyme Q10) significantly improve patient outcomes.
Area of Science:
- Biochemistry
- Mitochondrial Medicine
- Genetics
Background:
- Respiratory-chain deficiencies are a diverse group of severe, often untreatable, inherited metabolic disorders.
- Coenzyme Q10 (ubiquinone) deficiency is a specific subclass requiring timely and precise diagnosis for effective management.
Observation:
- Two siblings presented with severe encephalomyopathy and renal failure, indicating a potential mitochondrial defect.
- Biochemical investigations revealed deficient coenzyme Q10-dependent respiratory-chain activities in multiple tissues.
Findings:
- Cellular coenzyme Q10 levels were undetectable, confirmed by radiolabelling studies, supporting a diagnosis of widespread coenzyme Q10 deficiency.
- In vitro studies showed that exogenous quinones stimulated respiration and enzyme activity, suggesting a therapeutic potential.
Implications:
- Oral administration of ubidecarenone (coenzyme Q10) led to substantial clinical improvement in the affected siblings over a 3-year period.
- This highlights the importance of recognizing quinone-responsive respiratory-chain enzyme deficiencies as a treatable condition.
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