title: Decreased serum ubiquinone-10 concentrations in phenylketonuria.
abstract: BACKGROUND
  Ubiquinone-10 is a lipid with important metabolic functions that may be decreased in phenylketonuria (PKU) because patients with PKU consume diets restricted in natural proteins.
  
  
  OBJECTIVE
  We studied serum ubiquinone-10 concentrations in PKU patients.
  
  
  METHODS
  This was a retrospective, transversal study in which we compared serum ubiquinone-10, plasma cholesterol, plasma tyrosine, and plasma phenylalanine concentrations in 43 PKU patients with concentrations in a reference population (n = 102). Serum ubiquinone-10 concentrations were analyzed by HPLC with ultraviolet detection. Plasma tyrosine and phenylalanine were measured by ion-exchange chromatography.
  
  
  RESULTS
  Serum ubiquinone-10 concentrations in PKU patients were significantly lower than in the reference population (P < 0.01 for patients aged 1 mo to <8 y and P < 0.00005 for patients aged 8-33 y). Moreover, 5 of 18 PKU patients (28%) in the younger age group and 10 of 23 (43%) in the older age group had serum ubiquinone-10 concentrations below the reference interval.
  
  
  CONCLUSIONS
  Serum ubiquinone-10 deficiency appears to be related to the restricted diet of PKU patients. Because serum ubiquinone-10 plays a major antioxidant role in the protection of circulating lipoproteins, the correction of ubiquinone-10 concentrations should be considered in PKU patients. Further investigation seems advisable to elucidate whether the deficiency in serum ubiquinone-10 status is clinically significant.
authors.affiliation: Servei de Bioquímica, Servei de Pediatría i Neuropediatría, Unitat Integrada, Hospital Sant Joan de Déu/Hospital Clinic, Universitat de Barcelona, Spain.
authors.forename: R
authors.initials: R
authors.lastname: Artuch
authors.forename: M A
authors.initials: MA
authors.lastname: Vilaseca
authors.forename: J
authors.initials: J
authors.lastname: Moreno
authors.forename: N
authors.initials: N
authors.lastname: Lambruschini
authors.forename: F J
authors.initials: FJ
authors.lastname: Cambra
authors.forename: J
authors.initials: J
authors.lastname: Campistol
mesh_terms: D000293:Adolescent; D000328:Adult; D000931:Antidotes / Q000378:metabolism*; D002648:Child; D002675:Child, Preschool; D002784:Cholesterol / Q000097:blood*; D002851:Chromatography, High Pressure Liquid; D002852:Chromatography, Ion Exchange; D004032:Diet; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D010649:Phenylalanine / Q000097:blood*; D010661:Phenylketonurias / Q000097:blood*; D012016:Reference Values; D012189:Retrospective Studies; D014443:Tyrosine / Q000097:blood*; D014451:Ubiquinone / Q000097:blood*
chemical_list: D000931:Antidotes; D014451:Ubiquinone; D014443:Tyrosine; D010649:Phenylalanine; D002784:Cholesterol; C025204:Ubiquinone Q2