A novel and rapid long-chain hydroxyacyl-CoA dehydrogenase assay

Extract

Mitochondrial beta-oxidation is key physiological process in higher eukaryotes and consists of a four step reaction involving the concerted action of several chain length specific enzymes. Mitochondrial trifunctional protein (MTP) harbours three enzymatic activities required for the oxidation of long-chain fatty acids. deficiency of the second enzymatic activity of MTP, i.e. long-chain hydroxyacyl-CoA dehydrogenase activity (LCHAD), is a severe multiorgan disorder that has been included in the newborn screening programme. Identification of LCHAD deficiency occurs via the rapid and sensitive quantification of acylcarnitines in plasma or serum. Although bloodspot acylcarnitine profiling is highly indicative for this disorder, a conclusive diagnosis comes from a specific enzyme assay and/ or mutation analysis. However, mutation analysis is more time consuming. Measurement of LCHAD enzymatic activity is hampered by the presence of short-chain hydroxyacyl-CoA dehydrogenase (SCHAD), which also contributes to the enzymatic reaction. Therefore, we have developed and applied several means to eliminate the contribution of SCHAD. Here we report a novel, more direct, less time-consuming and less costly method. …