X-linked adrenoleukodystrophy: defective peroxisomal oxidation of very long chain fatty acids but not of very long chain fatty acyl-CoA esters.

We investigated the peroxisomal fatty acid beta-oxidation system in liver and cultured skin fibroblasts from patients with X-linked adrenoleukodystrophy known to accumulate very long chain fatty acids. In order to examine whether the deficient peroxisomal oxidation of very long chain fatty acids in these patients results from a deficiency in one of the peroxisomal beta-oxidation enzyme proteins (acyl-CoA oxidase, bifunctional protein with enoyl-CoA hydratase and 3-hydroxyacyl-CoA dehydrogenase activities and 3-oxoacyl-CoA thiolase) we carried out immunoblotting experiments using antibodies directed against the peroxisomal beta-oxidation enzyme proteins from rat liver. Furthermore, we studied the oxidation of palmitoyl-CoA and lignoceroyl-CoA in homogenates of fibroblasts from the patients. The results indicate that the peroxisomal beta-oxidation enzyme proteins are not only present immunologically but also functionally active which suggests that the defect in X-linked adrenoleukodystrophy is, indeed, as recently suggested by Hashmi and coworkers (FEBS Lett 1986;196:247-250) at the level of a deficient peroxisomal activation of very long chain fatty acids.