Investigation of beta-oxidation intermediates in normal and MCAD-deficient human fibroblasts using tandem mass spectrometry.
Mitochondrial fatty acid beta-oxidation was studied by incubating stable isotope-labeled fatty acid probes with human fibroblasts in the presence of L-carnitine. The acylcarnitine intermediates produced were analyzed by tandem mass spectrometry. Oxidation by normal fibroblasts produced specific acylcarnitine intermediates corresponding to acyl-CoA dehydrogenase substrates mainly of 10 or less carbons. These probes demonstrated that the pathway, involving all beta-oxidative steps, could be examined. Oxidation of the same precursors by cells with medium chain acyl-CoA dehydrogenase (EC 1.3.99.2) ( MCAD) deficiency, which is caused by different DNA mutations, produced acylcarnitine profiles which appear to be specific to this enzyme defect, regardless of the DNA mutation. Increased amounts of octanoyl-, decanoyl-, or decenoylcarnitine were detected. The ratios of octanoylcarnitine to decanoyl- or decenoylcarnitine appear specific for MCAD deficiency. Even though the concentration of labeled decenoylcarnitine (C10:1) was elevated in incubations of MCAD-deficient cells with labeled linoleate or with a fatty acid mixture which included palmitate, oleate, and linoleate, the predominant intermediate was octanoylcarnitines. These results suggest that MCAD-deficient cells readily convert decanoyl-CoA into octanoyl-CoA. This in vitro system could be utilized to study fatty acid oxidation disorders and to study the origins of metabolic intermediates associated with them.[1]References
- Investigation of beta-oxidation intermediates in normal and MCAD-deficient human fibroblasts using tandem mass spectrometry. Nada, M.A., Chace, D.H., Sprecher, H., Roe, C.R. Biochem. Mol. Med. (1995) [Pubmed]
Annotations and hyperlinks in this abstract are from individual authors of WikiGenes or automatically generated by the WikiGenes Data Mining Engine. The abstract is from MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.About WikiGenesOpen Access LicencePrivacy PolicyTerms of Useapsburg
