Evidence against alpha-hydroxyphytanic acid as an intermediate in the metabolism of phytanic acid.
It was established 20 years ago that phytanic acid is degraded by an initial alpha-oxidation, and that alpha-hydroxyphytanic acid is an intermediate in the reaction. Patients with Refsum's disease, as well as those with the so-called peroxisomal disorders, have an enzymatic defect in this alpha-oxidation. The present work shows that when cultured skin fibroblasts from both groups of patients as well as from healthy controls are incubated with (1-14C)phytanic acid, the only radioactive compounds which can be detected are 14CO2 and unmetabolised phytanic acid. The degradation of (1-14C)alpha-hydroxyphytanic acid to 14CO2 takes place in the mitochondrial fraction of rat liver. Unlabelled alpha-hydroxyphytanic acid added to rat liver homogenate or mitochondria and (1-14C)phytanic acid reduced considerably the production of 14CO2. However, 14C-labelling of the alpha-hydroxyphytanic acid pool did not occur. Thus, we have been unable to confirm the previous demonstration of alpha-hydroxyphytanic acid as an intermediate in the degradation of phytanic acid.
Skjeldal
O H
OH
Institute of Clinical Biochemistry, University of Oslo, Rikshospitalet, Norway.
Stokke
O
O
D000818:Animals; D002478:Cells, Cultured; D004537:Eicosanoic Acids / Q000378:metabolism*; D005347:Fibroblasts / Q000378:metabolism; D006801:Humans; D008099:Liver / Q000378:metabolism; D010084:Oxidation-Reduction; D010831:Phytanic Acid / Q000031:analogs & derivatives / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D012035:Refsum Disease / Q000378:metabolism; D012867:Skin / Q000378:metabolism; D013347:Subcellular Fractions / Q000378:metabolism
D004537:Eicosanoic Acids; D010831:Phytanic Acid; C002585:2-hydroxyphytanic acid