Brain phenylalanine concentrations in phenylketonuria: research and treatment of adults.
OBJECTIVE
To assess the effects of 2 pharmacologic interventions (amino acid supplements) on the brain levels of phenylalanine (Phe) in adults with phenylketonuria (PKU).


METHODS
A prospective study was conducted in an outpatient treatment and follow-up setting. The volunteers who were recruited for the first intervention included 4 subjects with classic PKU. The second intervention included 3 adults with classic PKU. The first intervention consisted of dietary supplementation during 1 day with Phlexy 10. Two individuals were given a dose of 0.5 g/kg/d, and 2 were given 1.0 g/kg/d. The second intervention consisted of dietary supplementation with PreKUnil at 0.4 g kg/d over a period of 6 months. Brain Phe was measured by magnetic resonance spectroscopy. The number of the patients involved precluded analysis for significance.


RESULTS
The first, shorter intervention resulted in a decrease in brain Phe. The second intervention resulted in a 20% decrease in brain Phe, which was maintained after 6 months of treatment.


CONCLUSIONS
Dietary supplementation of large neutral amino acids seems to lower the brain Phe in adults who have PKU and have difficulty following their diet.
Moats
Rex A
RA
Department of Radiology, University of California/Keck School of Medicine at Childrens Hospital Los Angeles, Los Angeles, California 90027, USA. rmoats@chla.usc.edu
Moseley
Kathryn D
KD
Koch
Richard
R
Nelson
Marvin
M
D000328:Adult; D021542:Amino Acids, Neutral / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use*; D001921:Brain / Q000378:metabolism*; D018753:Diet, Protein-Restricted; D019587:Dietary Supplements; D005260:Female; D006801:Humans; D008297:Male; D010649:Phenylalanine / Q000378:metabolism*; D010661:Phenylketonurias / Q000178:diet therapy / Q000188:drug therapy* / Q000378:metabolism; D011446:Prospective Studies
D021542:Amino Acids, Neutral; D010649:Phenylalanine