Acylcarnitine profiles in fibroblasts from patients with respiratory chain defects can resemble those from patients with mitochondrial fatty acid β-oxidation disorders

Abstract

Mitochondrial fatty acid β-oxidation (FAO) is coupled to the respiratory chain (RC). Functional defects of one pathway may lead to secondary alteration in flux through the other. We investigated the acylcarnitine profiles in cultured fibroblasts obtained from 14 healthy subjects, 31 patients with 8 different primary enzyme deficiencies of FAO, and 16 patients with primary RC defects including both isolated and multiple enzyme complex defects. Intact cells were incubated in media containing deuterium-labeled hexadecanoic acid and L-carnitine, and the acylcarnitines analysed using an electrospray tandem mass spectrometer. All FAO-deficient cell lines revealed disease-specific acylcarnitine pro..