Creatine metabolism in combined methylmalonic aciduria and homocystinuria.
Methylation is an important aspect of many fundamental biological processes including creatine biosynthesis. We studied five patients with an inborn error of cobalamin metabolism to characterize the relation between homocysteine and creatine metabolism. Plasma guanidinoacetate concentrations were increased, 14.9 +/- 4.8 micromol/L (p < 0.0001), whereas plasma creatine concentrations were in the low reference range, 43.8 +/- 20.7 micromol/L (p = not significant). Individuals with combined methylmalonic aciduria and homocystinuria have a functional impairment of the creatine synthetic pathway probably secondary to a relative depletion of labile methyl groups. The neurotoxic effects of guanidinoacetate may be partly responsible for the observed neurological phenotype.
Bodamer
Olaf A
OA
Unit of Biochemical Genetics, Department of Pediatrics, University of Vienna Children's Hospital, Vienna, Austria. olaf.bodamer@meduniwien.ac.at
Sahoo
Trilochan
T
Beaudet
Arthur L
AL
O'Brien
William E
WE
Bottiglieri
Teodoro
T
Stöckler-Ipsiroglu
Sylvia
S
Wagner
Conrad
C
Scaglia
Fernando
F
D000328:Adult; D000592:Amino Acid Metabolism, Inborn Errors / Q000378:metabolism*; D002648:Child; D002675:Child, Preschool; D003401:Creatine / Q000378:metabolism*; D005260:Female; D005998:Glycine / Q000031:analogs & derivatives* / Q000032:analysis; D006710:Homocysteine / Q000378:metabolism; D006712:Homocystinuria / Q000378:metabolism*; D006801:Humans; D008297:Male; D008715:Methionine / Q000378:metabolism; D008764:Methylmalonic Acid / Q000097:blood / Q000652:urine*; D014805:Vitamin B 12 / Q000378:metabolism
D006710:Homocysteine; D008764:Methylmalonic Acid; D008715:Methionine; C004946:glycocyamine; D003401:Creatine; D014805:Vitamin B 12; D005998:Glycine