A longitudinal study of antioxidant status in phenylketonuric patients.

Objectives: To investigate the implications of the three main factors of the antioxidant system reported in relation to oxidative damage in phenylketonuric patients: selenium, ubiquinone-10 (Q10) and antioxidant enzymes over 3 years of metabolic follow-up.

Design And Methods: Longitudinal study of 46 phenylketonuric patients (age range: 6 months-34 years). Antioxidants were measured by atomic absorption spectrophotometric, chromatographic and spectrophotometric procedures.

Lipophilic antioxidants in patients with phenylketonuria.

Background: Low serum ubiquinone-10 concentrations have been described in phenylketonuric patients fed natural-protein-restricted diets. Such low concentrations may be related to increased free radical damage.

Objective: We evaluated the relation between low serum ubiquinone-10 concentrations and other lipophilic antioxidants (tocopherol and retinol), selenium, glutathione peroxidase activity, and malondialdehyde concentrations as a marker of lipid peroxidation.

Ubiquinone-10 content in lymphocytes of phenylketonuric patients.

Objectives: To investigate the ubiquinone-10 content in lymphocytes from phenylketonuric patients.

Design And Methods: We compared 23 patients with 25 age-matched controls. Ubiquinone-10 was analyzed by HPLC with electrochemical detection.

Monitoring of idebenone treatment in patients with Friedreich's ataxia by high-pressure liquid chromatography with electrochemical detection.

Idebenone is a quinone analog that is applied in the treatment of several neurological disorders including Friedreich ataxia and mitochondrial encephalomyopathies. Our aim was to develop an easy and sensitive analytical HPLC-procedure for the determination of idebenone in the serum of patients treated with this drug. Serum samples from nine paediatric patients diagnosed with Friedreich ataxia and receiving idebenone treatment were analyzed.