Pristanic acid beta-oxidation in peroxisomal disorders: studies in cultured human fibroblasts

To investigate the individual steps of peroxisomal beta-oxidation, human fibroblasts from controls and patients affected by different peroxisomal disorders were incubated for 96 h with pristanic acid. Hereafter, 2,3-pristenic acid and 3-hydroxypristanic acid in the incubation medium were quantified by stable isotope dilution gas chromatography mass spectrometry (GC-MS). In control fibroblasts, both intermediates were formed and excreted into the medium in significant amounts. In cells from patients affected with different types of generalized peroxisomal disorders, the formation of both intermediates was absent or low, depending on the clinical severity of the disorder. In fibroblasts from patients affected with bifunctional protein deficiency, the concentrations of 2,3-pristenic acid and 3-hydroxypristanic acid in the medium were higher than in control cell lines.