51
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Touma EH, Rashed MS, Vianey-Saban C, Sakr A, Divry P, Gregersen N, Andresen BS. A severe genotype with favourable outcome in very long chain acyl-CoA dehydrogenase deficiency. Arch Dis Child 2001; 84:58-60. [PMID: 11124787 PMCID: PMC1718627 DOI: 10.1136/adc.84.1.58] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
A patient with very long chain acyl-CoA dehydrogenase (VLCAD) deficiency is reported. He had a severe neonatal presentation and cardiomyopathy. He was found to be homozygous for a severe mutation with no residual enzyme activity. Tandem mass spectrometry on dried blood spots revealed increased long chain acylcarnitines. VLCAD enzyme activity was severely decreased to 2% of control levels. Dietary management consisted of skimmed milk supplemented with medium chain triglycerides and L-carnitine. Outcome was good and there was no acute recurrence.
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Affiliation(s)
- E H Touma
- Laboratory of Professor Loiselet, Faculty of Medicine, University St Joseph, Damascus Street, PO Box 11-5076, Beirut, Lebanon.
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52
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Watanabe H, Orii KE, Fukao T, Song XQ, Aoyama T, IJlst L, Ruiter J, Wanders RJ, Kondo N. Molecular basis of very long chain acyl-CoA dehydrogenase deficiency in three Israeli patients: identification of a complex mutant allele with P65L and K247Q mutations, the former being an exonic mutation causing exon 3 skipping. Hum Mutat 2000; 15:430-8. [PMID: 10790204 DOI: 10.1002/(sici)1098-1004(200005)15:5<430::aid-humu4>3.0.co;2-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Very long chain acyl-CoA dehydrogenase (VLCAD) deficiency is a life-threatening disorder of mitochondrial fatty acid beta-oxidation. We identified four novel mutations in three unrelated patients. All patients had the severe childhood form of VLCAD deficiency with early onset and high mortality. Immunoblot analysis revealed that VLCAD protein was undetectable in patients 2 and 3, whereas normal-size VLCAD protein and an aberrant form of VLCAD (4kDa smaller) were detected in patient 1. As expected, null mutations were found in patients 2 and 3: patient 2 is homozygous for a frameshift mutation, del 4 bp at 798-801, and patient 3 is homozygous for a nonsense mutation 65C>A(S22X). Patient 1 was homozygous for a complex mutant allele containing two alterations, including a 194C>T transition (P65L) and 739A>C transversion (K247Q); in the case of P65L, the amino acid change does not reduce enzyme activity. However, the nucleotide change resulted in exon 3 skipping, whereas the latter K247Q mutation had a drastic effect on enzyme activity. We verified these events by in vivo splicing experiments and transient expression analysis of mutant cDNAs. The P65L mutation locates 11 bases upstream of a splice donor site of intron 3. This is an example of an exonic mutation which affects exon-splicing.
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Affiliation(s)
- H Watanabe
- Department of Pediatrics, Gifu University School of Medicine, Gifu, Japan
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53
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Pons R, Cavadini P, Baratta S, Invernizzi F, Lamantea E, Garavaglia B, Taroni F. Clinical and molecular heterogeneity in very-long-chain acyl-coenzyme A dehydrogenase deficiency. Pediatr Neurol 2000; 22:98-105. [PMID: 10738914 DOI: 10.1016/s0887-8994(99)00132-0] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Very-long-chain acyl-coenzyme A dehydrogenase (VLCAD) deficiency is an increasingly recognized defect of mitochondrial fatty acid beta-oxidation manifesting with episodes of metabolic decompensation or isolated recurrent myoglobinuria. In this report the clinical, biochemical, and molecular studies in a series of five patients (four Italian and one Spanish) with this disorder are discussed. Biochemical studies included the determination of fibroblast substrate oxidation rates and enzyme activity and Western blot analysis of VLCAD protein. Molecular analysis was performed by sequencing the VLCAD gene from the genomic DNA. Clinical features were within the spectrum previously reported. Four patients presented in infancy or childhood with episodes of severe metabolic decompensation and dicarboxylic aciduria. Two exhibited cardiomyopathy. The fifth patient presented with isolated recurrent rhabdomyolysis, with no cardiomyopathy or dicarboxylic aciduria. In all patients a significant loss of VLCAD activity associated with a marked reduction of VLCAD protein levels occurred. Molecular analysis disclosed one novel missense mutation (Cys437Tyr) and four previously reported mutations, including two missense substitutions (Phe418Leu and Arg419Trp), a single amino acid deletion (Lys258del), and one splice site mutation (IVS8-C(-2)), which was present in all four Italian patients. All patients exhibited compound heterozygosity. The phenotypic variability and the high genotypic heterogeneity of this hereditary metabolic disorder is reported.
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Affiliation(s)
- R Pons
- Laboratory of Cellular Pathology, Istituto Nazionale Neurologico Carlo Besta, Milan, Italy
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54
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He G, Yang BZ, Roe DS, Teramoto R, Aleck K, Grebe TA, Roe CR, Ding JH. Identification of two novel mutations in the hypoglycemic phenotype of very long chain acyl-CoA dehydrogenase deficiency. Biochem Biophys Res Commun 1999; 264:483-7. [PMID: 10529389 DOI: 10.1006/bbrc.1999.1411] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Very long chain acyl-CoA dehydrogenase (VLCAD) catalyzes the initial step of long chain fatty acid oxidation in the mitochondria. Patients with VLCAD deficiency have recently been observed with two clinical phenotypes. The cardiac form presents with an early onset cardiomyopathy and a high incidence of infant death, while the hypoglycemic form resembles medium chain acyl-CoA dehydrogenase (MCAD) manifesting with hypoketotic hypoglycemia. In our investigation on the molecular basis for these phenotypes, we identified two novel mutations in one VLCAD patient with the hypoglycemic form, a C953T (Pro318Leu) mutation in exon 10 resulting in a substitution of proline 318 by leucine on one allele, and a C1194A (Tyr398Stop) mutation in exon 12 which created a premature stop codon TAA on another allele. The Tyr398Stop mutation may result in a truncated protein or instable messenger RNA.
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Affiliation(s)
- G He
- Kimberly H. Courtwright & Joseph W. Summers Institute of Metabolic Disease, Baylor University Medical Center, Dallas, Texas, 75226, USA
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55
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Merinero B, Pascual Pascual SI, Pérez-Cerdá C, Gangoiti J, Castro M, Garcia MJ, Pascual Castroviejo I, Vianey-Saban C, Andresen B, Gregersen N, Ugarte M. Adolescent myopathic presentation in two sisters with very long-chain acyl-CoA dehydrogenase deficiency. J Inherit Metab Dis 1999; 22:802-10. [PMID: 10518280 DOI: 10.1023/a:1005553907216] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Two sisters were investigated at the ages of 20 and 13 years owing to persistently increased serum creatine kinase and recurrent episodes of rhabdomyolysis after emotional stress in the older and myalgias in the younger. The finding of increased levels of cis-5-tetradecenoic acid (C14:1) in plasma, severe hypocarnitinaemia and the absence of a pathological dicarboxylic aciduria in both sisters suggested a very long-chain acyl-CoA dehydrogenase (VLCAD) deficiency. Reduced [1-(14)C]palmitate oxidation and deficient mitochondrial VLCAD activity in fibroblasts were found. Mutation analysis revealed compound heterozygosity for Asp365His and Arg410His changes. This late-onset, milder clinical presentation differs from the other two more severe infantile phenotypes described, since there is no hypoglycaemia or cardiac disease. Fatty acid oxidation defects should be investigated in all cases with rhabdomyolysis beginning in adolescence or early adulthood.
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Affiliation(s)
- B Merinero
- Dpto. Biología Molecular, Universidad Autónoma Madrid, Spain
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56
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Scholte HR, Van Coster RN, de Jonge PC, Poorthuis BJ, Jeneson JA, Andresen BS, Gregersen N, de Klerk JB, Busch HF. Myopathy in very-long-chain acyl-CoA dehydrogenase deficiency: clinical and biochemical differences with the fatal cardiac phenotype. Neuromuscul Disord 1999; 9:313-9. [PMID: 10407852 DOI: 10.1016/s0960-8966(99)00032-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
A 30-year-old man suffered since the age of 13 years from exercise induced episodes of intense generalised muscle pain, weakness and myoglobinuria. Fasting ketogenesis was low, while blood glucose remained normal. Muscle mitochondria failed to oxidise palmitoylcarnitine. Palmitoyl-CoA dehydrogenase was deficient in muscle and fibroblasts, consistent with deficiency of very-long-chain acyl-CoA dehydrogenase (VLCAD). The gene of this enzyme had a homozygous deletion of three base pairs in exon 9, skipping lysine residue 238. Fibroblasts oxidised myristate, palmitate and oleate at a rate of 129, 62 and 38% of controls. In contrast to patients with cardiac VLCAD deficiency, our patient had no lipid storage, a normal heart function, a higher rate of oleate oxidation in fibroblasts and normal free carnitine in plasma and fibroblasts. 31P-nuclear magnetic resonance spectroscopy of muscle showed a normal oxidative phosphorylation as assessed by phosphocreatine recovery, but a significant increase in pH and in Pi/ATP ratio.
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Affiliation(s)
- H R Scholte
- Department of Biochemistry, Erasmus University, Rotterdam, The Netherlands.
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57
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Wanders RJ, Vreken P, den Boer ME, Wijburg FA, van Gennip AH, IJlst L. Disorders of mitochondrial fatty acyl-CoA beta-oxidation. J Inherit Metab Dis 1999; 22:442-87. [PMID: 10407780 DOI: 10.1023/a:1005504223140] [Citation(s) in RCA: 186] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
In recent years tremendous progress has been made with respect to the enzymology of the mitochondrial fatty acid beta-oxidation machinery and defects therein. Firstly, a number of new mitochondrial beta-oxidation enzymes have been identified, including very-long-chain acyl-CoA dehydrogenase (VLCAD) and mitochondrial trifunctional protein (MTP). Secondly, the introduction of tandem MS for the analysis of plasma acylcarnitines has greatly facilitated the identification of patients with a defect in fatty acid oxidation (FAO). These two developments explain why the number of defined FAO disorders has increased dramatically, making FAO disorders the most rapidly growing group of inborn errors of metabolism. In this review we describe the current state of knowledge of the enzymes involved in the mitochondrial oxidation of straight-chain, branched-chain and (poly)unsaturated fatty acyl-CoAs as well as disorders of fatty acid oxidation. The laboratory diagnosis of these disorders is described, with particular emphasis on the methods used to identify the underlying enzyme defect and the molecular mutations. In addition, a simple flowchart is presented as a guide to the identification of mitochondrial FAO-disorders. Finally, treatment strategies are discussed briefly.
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Affiliation(s)
- R J Wanders
- Academic Medical Center, University of Amsterdam, The Netherlands.
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58
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Andresen BS, Olpin S, Poorthuis BJ, Scholte HR, Vianey-Saban C, Wanders R, Ijlst L, Morris A, Pourfarzam M, Bartlett K, Baumgartner ER, deKlerk JB, Schroeder LD, Corydon TJ, Lund H, Winter V, Bross P, Bolund L, Gregersen N. Clear correlation of genotype with disease phenotype in very-long-chain acyl-CoA dehydrogenase deficiency. Am J Hum Genet 1999; 64:479-94. [PMID: 9973285 PMCID: PMC1377757 DOI: 10.1086/302261] [Citation(s) in RCA: 227] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
Very-long-chain acyl-CoA dehydrogenase (VLCAD) catalyzes the initial rate-limiting step in mitochondrial fatty acid beta-oxidation. VLCAD deficiency is clinically heterogenous, with three major phenotypes: a severe childhood form, with early onset, high mortality, and high incidence of cardiomyopathy; a milder childhood form, with later onset, usually with hypoketotic hypoglycemia as the main presenting feature, low mortality, and rare cardiomyopathy; and an adult form, with isolated skeletal muscle involvement, rhabdomyolysis, and myoglobinuria, usually triggered by exercise or fasting. To examine whether these different phenotypes are due to differences in the VLCAD genotype, we investigated 58 different mutations in 55 unrelated patients representing all known clinical phenotypes and correlated the mutation type with the clinical phenotype. Our results show a clear relationship between the nature of the mutation and the severity of disease. Patients with the severe childhood phenotype have mutations that result in no residual enzyme activity, whereas patients with the milder childhood and adult phenotypes have mutations that may result in residual enzyme activity. This clear genotype-phenotype relationship is in sharp contrast to what has been observed in medium-chain acyl-CoA dehydrogenase deficiency, in which no correlation between genotype and phenotype can be established.
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Affiliation(s)
- B S Andresen
- Research Unit for Molecular Medicine, Skejby Sygehus, DK 8200 Arhus N, Denmark, Germany.
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59
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Kurtz DM, Rinaldo P, Rhead WJ, Tian L, Millington DS, Vockley J, Hamm DA, Brix AE, Lindsey JR, Pinkert CA, O'Brien WE, Wood PA. Targeted disruption of mouse long-chain acyl-CoA dehydrogenase gene reveals crucial roles for fatty acid oxidation. Proc Natl Acad Sci U S A 1998; 95:15592-7. [PMID: 9861014 PMCID: PMC28088 DOI: 10.1073/pnas.95.26.15592] [Citation(s) in RCA: 169] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/1998] [Indexed: 11/18/2022] Open
Abstract
Abnormalities of fatty acid metabolism are recognized to play a significant role in human disease, but the mechanisms remain poorly understood. Long-chain acyl-CoA dehydrogenase (LCAD) catalyzes the initial step in mitochondrial fatty acid oxidation (FAO). We produced a mouse model of LCAD deficiency with severely impaired FAO. Matings between LCAD +/- mice yielded an abnormally low number of LCAD +/- and -/- offspring, indicating frequent gestational loss. LCAD -/- mice that reached birth appeared normal, but had severely reduced fasting tolerance with hepatic and cardiac lipidosis, hypoglycemia, elevated serum free fatty acids, and nonketotic dicarboxylic aciduria. Approximately 10% of adult LCAD -/- males developed cardiomyopathy, and sudden death was observed in 4 of 75 LCAD -/- mice. These results demonstrate the crucial roles of mitochondrial FAO and LCAD in vivo.
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MESH Headings
- Acyl-CoA Dehydrogenase, Long-Chain/deficiency
- Acyl-CoA Dehydrogenase, Long-Chain/genetics
- Acyl-CoA Dehydrogenase, Long-Chain/metabolism
- Animals
- Disease Models, Animal
- Fatty Acids, Nonesterified/blood
- Fatty Acids, Nonesterified/metabolism
- Humans
- Lipid Metabolism, Inborn Errors/enzymology
- Lipid Metabolism, Inborn Errors/genetics
- Lipid Metabolism, Inborn Errors/pathology
- Liver/metabolism
- Liver/pathology
- Mice
- Mice, Knockout
- Mitochondria, Liver/enzymology
- Muscle, Skeletal/metabolism
- Substrate Specificity
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Affiliation(s)
- D M Kurtz
- Department of Comparative Medicine, Schools of Medicine and Dentistry, University of Alabama, Birmingham, AL 35294, USA
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60
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Cox GF, Souri M, Aoyama T, Rockenmacher S, Varvogli L, Rohr F, Hashimoto T, Korson MS. Reversal of severe hypertrophic cardiomyopathy and excellent neuropsychologic outcome in very-long-chain acyl-coenzyme A dehydrogenase deficiency. J Pediatr 1998; 133:247-53. [PMID: 9709714 DOI: 10.1016/s0022-3476(98)70228-8] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Very-long-chain acyl-coenzyme A dehydrogenase (VLCAD) deficiency is a disorder of fatty acid beta oxidation that reportedly has high rates of morbidity and mortality. We describe the outcome of a 5-year-old girl with VLCAD deficiency who was first seen at 5 months of age with severe hypertrophic cardiomyopathy, hepatomegaly, encephalopathy, and hypotonia. Biochemical studies indicated VLCAD deficiency caused by a stable yet inactive enzyme. Molecular genetic analysis of her VLCAD gene revealed a T1372C (F458L) missense mutation and a 1668 ACAG 1669 splice site mutation. After initial treatment with intravenous glucose and carnitine, the patient has thrived on a low-fat diet supplemented with medium-chain triglyceride oil and carnitine and avoidance of fasting. Her ventricular hypertrophy resolved significantly over 1 year, and cognitively, she is in the superior range for age. Clinical recognition of VLCAD deficiency is important because it is one of the few directly treatable causes of cardiomyopathy in children.
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Affiliation(s)
- G F Cox
- Department of Medicine, Children's Hospital, Boston, Massachusetts 02115, USA
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61
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Costa CG, Dorland L, de Almeida IT, Jakobs C, Duran M, Poll-The BT. The effect of fasting, long-chain triglyceride load and carnitine load on plasma long-chain acylcarnitine levels in mitochondrial very long-chain acyl-CoA dehydrogenase deficiency. J Inherit Metab Dis 1998; 21:391-9. [PMID: 9700596 DOI: 10.1023/a:1005354624735] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
We studied a 10-year-old patient with very long-chain acyl-CoA dehydrogenase (VLCAD) deficiency who was originally (mis)diagnosed as having systemic carnitine deficiency. He was subjected to a fasting test, a long-chain triglyceride (LCT) loading test (1.5 g/kg) and an intravenous carnitine clearance test (0.25 mumol/kg per min). Plasma acylcarnitines were analysed using a quantitative GC-CI-MS method. During fasting, all long-chain acylcarnitines with a chain length of C14 and higher (especially C14:1) increased dramatically. Total plasma long-chain acylcarnitine reached a concentration of 28.6 mumol/L. LCT loading resulted in a moderate increase, mainly of the C18 esters. The carnitine infusion, which led to a supranormal plasma free carnitine concentration, gave only a slight but generalized rise of long-chain acylcarnitines. Although only one patient could be tested, the results suggest that the accumulation of potentially toxic long-chain acylcarnitines in VLCAD deficiency is provoked by fasting, LCT loading and carnitine supplementation. Therapy should be adjusted accordingly.
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Affiliation(s)
- C G Costa
- Free University Hospital, Department of Clinical Chemistry, Amsterdam, The Netherlands
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62
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Souri M, Aoyama T, Hoganson G, Hashimoto T. Very-long-chain acyl-CoA dehydrogenase subunit assembles to the dimer form on mitochondrial inner membrane. FEBS Lett 1998; 426:187-90. [PMID: 9599005 DOI: 10.1016/s0014-5793(98)00343-3] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
This paper describes the process of dimer assembly of mitochondrial very-long-chain acyl-CoA dehydrogenase (VLCAD) subunit. Mature VLCAD is a homodimer of a 70-kDa protein associated with the mitochondrial membrane. Newly synthesized VLCAD was present as a monomer and the major fraction was associated with the mitochondrial inner membrane. The association of VLCAD subunit with the mitochondrial membrane was observed early during dimer formation. In contrast, a VLCAD monomeric mutant S583W, a novel mutation identified from a patient with VLCAD deficiency, did not associate with the mitochondrial membrane after import and the major fraction remained in the mitochondrial matrix. These results suggest that association of VLCAD protein with mitochondrial inner membrane is necessary for dimer assembly and formation of mature VLCAD.
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Affiliation(s)
- M Souri
- Department of Biochemistry, Shinshu University School of Medicine, Matsumoto, Nagano, Japan.
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63
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Smelt AH, Poorthuis BJ, Onkenhout W, Scholte HR, Andresen BS, van Duinen SG, Gregersen N, Wintzen AR. Very long chain acyl-coenzyme A dehydrogenase deficiency with adult onset. Ann Neurol 1998; 43:540-4. [PMID: 9546340 DOI: 10.1002/ana.410430422] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Very long chain acyl-coenzyme A (acyl-CoA) dehydrogenase (VLCAD) deficiency is a severe disorder of mitochondrial beta-oxidation in infants. We report adult onset of attacks of painful rhabdomyolysis. Gas chromatography identified strongly elevated levels of tetradecenoic acid, 14:1(n-9), tetradecadienoic acid, 14:2(n-6), and hexadecadienoic acid, 16:2(n-6). Palmitoyl-CoA and behenoyl-CoA dehydrogenase in fibroblasts were deficient. Muscle VLCAD activity was very low. DNA analysis revealed compound heterozygosity for two missense mutations in the VLCAD gene. The relatively mild clinical course may be due to residual enzyme activity as a consequence of the two missense mutations. Treatment with L-carnitine and medium chain triglycerides in the diet did not reduce the attacks of rhabdomyolysis.
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MESH Headings
- Acyl-CoA Dehydrogenase, Long-Chain/deficiency
- Acyl-CoA Dehydrogenase, Long-Chain/metabolism
- Adult
- Age of Onset
- Biopsy
- Ca(2+) Mg(2+)-ATPase/metabolism
- Carnitine/blood
- Cells, Cultured/metabolism
- Cells, Cultured/pathology
- Citrate (si)-Synthase/metabolism
- Exercise
- Fatty Acids, Unsaturated/analysis
- Fatty Acids, Unsaturated/metabolism
- Female
- Fibroblasts/metabolism
- Humans
- Mitochondria, Muscle/metabolism
- Mitochondria, Muscle/pathology
- Muscle, Skeletal/metabolism
- Muscle, Skeletal/pathology
- Oxygen Consumption
- Palmitic Acid/metabolism
- Rhabdomyolysis/enzymology
- Rhabdomyolysis/metabolism
- Rhabdomyolysis/pathology
- Skin/metabolism
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Affiliation(s)
- A H Smelt
- Department of Internal Medicine, Leiden University Medical Center, The Netherlands
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64
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Costa CG, Dorland L, Holwerda U, Tavares de Almeida I, Poll-The BT, Jakobs C, Duran M. Simultaneous analysis of plasma free fatty acids and their 3-hydroxy analogs in fatty acid β-oxidation disorders. Clin Chem 1998. [DOI: 10.1093/clinchem/44.3.463] [Citation(s) in RCA: 79] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
AbstractWe present a new derivatization procedure for the simultaneous gas chromatographic–mass spectrometric analysis of free fatty acids and 3-hydroxyfatty acids in plasma. Derivatization of target compounds involved trifluoroacetylation of hydroxyl groups and tert-butyldimethylsilylation of the carboxyl groups. This new derivatization procedure had the advantage of allowing the complete baseline separation of free fatty acids and 3-hydroxyfatty acids while the superior gas chromatographic and mass spectrometric properties of tert-butyldimethylsilyl derivatives remained unchanged, permitting a sensitive analysis of the target compounds. Thirty-nine plasma samples from control subjects and patients with known defects of mitochondrial fatty acid β-oxidation were analyzed. A characteristic increase of long-chain 3-hydroxyfatty acids was observed for all of the long-chain 3-hydroxyacyl-CoA dehydrogenase-deficient and mitochondrial trifunctional protein-deficient plasma samples. For medium-chain acyl-CoA dehydrogenase deficiency and very-long-chain acyl-CoA dehydrogenase deficiency, decenoic and tetradecenoic acids, respectively, were the main abnormal fatty acids, whereas the multiple acyl-CoA dehydrogenase-deficient patients showed variable increases of these unusual intermediates. The results showed that this selective and sensitive method is a powerful tool in the diagnosis and monitoring of mitochondrial fatty acid β-oxidation disorders.
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Affiliation(s)
- Catarina G Costa
- Centro de Metabolismos e Genética, University of Lisboa, Lisbon 1699, Portugal
- Free University Hospital, Department of Clinical Chemistry (Metabolic Unit), Amsterdam, The Netherlands
- Wilhelmina Kinderziekenhuis, University of Utrecht, Utrecht, The Netherlands
| | - Lambertus Dorland
- Wilhelmina Kinderziekenhuis, University of Utrecht, Utrecht, The Netherlands
| | - Ulbe Holwerda
- Free University Hospital, Department of Clinical Chemistry (Metabolic Unit), Amsterdam, The Netherlands
| | | | - Bwee-Tien Poll-The
- Wilhelmina Kinderziekenhuis, University of Utrecht, Utrecht, The Netherlands
| | - Cornelis Jakobs
- Free University Hospital, Department of Clinical Chemistry (Metabolic Unit), Amsterdam, The Netherlands
| | - Marinus Duran
- Wilhelmina Kinderziekenhuis, University of Utrecht, Utrecht, The Netherlands
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65
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Vianey-Saban C, Divry P, Brivet M, Nada M, Zabot MT, Mathieu M, Roe C. Mitochondrial very-long-chain acyl-coenzyme A dehydrogenase deficiency: clinical characteristics and diagnostic considerations in 30 patients. Clin Chim Acta 1998; 269:43-62. [PMID: 9498103 DOI: 10.1016/s0009-8981(97)00185-x] [Citation(s) in RCA: 115] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Very-long-chain acyl-CoA dehydrogenase (VLCAD) is an enzyme catalyzing the dehydrogenation of long-chain fatty acids in the first step of mitochondrial fatty acid oxidation. Using an ETF (electron transfer flavoprotein, the physiological electron acceptor of VLCAD) reduction assay, we identified VLCAD deficiency in cultured skin fibroblasts or liver tissue from 30 patients in 27 families. They clinically presented two phenotypes: a 'severe' presentation characterized by an early onset of symptoms, with hypertrophic cardiomyopathy and a high incidence of death, and a 'mild' form with hypoketotic hypoglycaemia, resembling MCAD (medium-chain acyl-CoA dehydrogenase) deficiency. Cells isolated from patients who develop cardiomyopathy characteristically accumulate longer-chain length acylcarnitines (hexadecanoylcarnitine and tetradecanoylcarnitine) when incubated with palmitate. However, cells from patients with the hypoglycaemic presentation produced relatively shorter-chain-length intermediates (mainly dodecanoylcarnitine). Inhibition of carnitine palmitoyl transferase I, in vitro, eliminated these intermediates with cells from both phenotypes indicating their intramitochondrial origin. Although the explanation for these distinct biochemical findings is not obvious, the correlation with the two phenotypes provides an opportunity for accurate prognosis and early implementation of appropriate treatment. Prenatal diagnosis of this life-threatening disorder was successfully performed in seven pregnancies in six of those families by assay of trophoblasts or amniocytes. In an at risk family, diagnosis of an affected fetus by measurement of VLCAD activity in noncultured chorionic villi allowed termination of the pregnancy before 13 weeks of gestation.
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Affiliation(s)
- C Vianey-Saban
- Unité d'Etude des Maladies Métaboliques, Hôpital Debrousse, Lyon, France
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66
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Martínez G, Jiménez-Sánchez G, Divry P, Vianey-Saban C, Riudor E, Rodés M, Briones P, Ribes A. Plasma free fatty acids in mitochondrial fatty acid oxidation defects. Clin Chim Acta 1997; 267:143-54. [PMID: 9469249 DOI: 10.1016/s0009-8981(97)00130-7] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Plasma free fatty acid profiles from patients suffering from various mitochondrial beta-oxidation deficiencies were analyzed by gas chromatography-mass spectrometry. cis-4-Decenoic acid (10:1n-6) in medium-chain acyl-CoA dehydrogenase deficiency and cis-5-tetradecenoic acid (14:1n-9) in very-long-chain and 3-hydroxy-long chain acyl-CoA dehydrogenase deficiencies are characteristic of these diseases. In addition, patients with 3-hydroxy-long chain acyl-CoA dehydrogenase deficiency showed a specific increase of 3-hydroxy-long chain fatty acids. The study of plasma free fatty acids is an easy and useful methodology for the diagnostic approach of some mitochondrial beta-oxidation deficiencies, allowing us to establish a quick differentiation between medium- and long-chain defects.
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Affiliation(s)
- G Martínez
- Institut de Bioquímica Clínica, Corporació Sanitària, Edifici Helios III Cl Mejia Lequerica, Barcelona, Spain
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67
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Sluysmans T, Tuerlinckx D, Hubinont C, Verellen-Dumoulin C, Brivet M, Vianey-Saban C. Very long chain acyl-coenzyme A dehydrogenase deficiency in two siblings: evolution after prenatal diagnosis and prompt management. J Pediatr 1997; 131:444-6. [PMID: 9329424 DOI: 10.1016/s0022-3476(97)80073-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
A boy had neonatal seizure, lethargy, and metabolic acidosis at presentation. He recovered completely, but the recurrence of a similar episode with associated cardiomyopathy and dicarboxylic aciduria at 10 months of age led to the recognition of a fatty acid oxidation defect. A diagnosis of very long chain acyl-coenzyme A dehydrogenase deficiency was later made by enzyme assay in culture fibroblasts from this child, as well as in cultured amniotic cells from a sibling fetus. This prenatal diagnosis forestalled neonatal injury by close clinical and metabolic monitoring of the second infant. Early diagnosis and management should potentially improve the generally poor prognosis for patients with very long chain acyl-coenzyme A dehydrogenase deficiency.
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Affiliation(s)
- T Sluysmans
- Department of Cardiologie pédiatrique, Université Catholique de Louvain, Brussels, Belgium
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68
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Baerlocher KE, Steinmann B, Aguzzi A, Krähenbühl S, Roe CR, Vianey-Saban C. Short-chain acyl-CoA dehydrogenase deficiency in a 16-year-old girl with severe muscle wasting and scoliosis. J Inherit Metab Dis 1997; 20:427-31. [PMID: 9266373 DOI: 10.1023/a:1005319120751] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- K E Baerlocher
- Children's Hospital, Eastern Switzerland, St. Gallen, Switzerland
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69
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Costa CG, Struys EA, Bootsma A, ten Brink HJ, Dorland L, Tavares de Almeida I, Duran M, Jakobs C. Quantitative analysis of plasma acylcarnitines using gas chromatography chemical ionization mass fragmentography. J Lipid Res 1997. [DOI: 10.1016/s0022-2275(20)37286-2] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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70
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Ha J, Lee JK, Kim KS, Witters LA, Kim KH. Cloning of human acetyl-CoA carboxylase-beta and its unique features. Proc Natl Acad Sci U S A 1996; 93:11466-70. [PMID: 8876158 PMCID: PMC38080 DOI: 10.1073/pnas.93.21.11466] [Citation(s) in RCA: 112] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Acetyl-CoA carboxylase, which has a molecular mass of 265 kDa (ACC-alpha), catalyzes the rate-limiting step in the biosynthesis of long-chain fatty acids. In this study we report the complete amino acid sequence and unique features of an isoform of ACC with a molecular mass of 275 kDa (ACC-beta), which is primarily expressed in heart and skeletal muscles. In these tissues, ACC-beta may be involved in the regulation of fatty acid oxidation, rather than fatty acid biosynthesis. ACC-beta contains an amino acid sequence at the N terminus which is about 200 amino acids long and may be uniquely related to the role of ACC-beta in controlling carnitine palmitoyltransferase I activity and fatty acid oxidation by mitochondria. If we exclude this unique sequence at the N terminus the two forms of ACC show about 75% amino acid identity. All of the known functional domains of ACC are found in the homologous regions. Human ACC-beta cDNA has an open reading frame of 7,343 bases, encoding a protein of 2,458 amino acids, with a calculated molecular mass of 276,638 Da. The mRNA size of human ACC-beta is approximately 10 kb and is primarily expressed in heart and skeletal muscle tissues, whereas ACC-alpha mRNA is detected in all tissues tested. A fragment of ACC-beta cDNA was expressed in Escherichia coli and antibodies against the peptide were generated to establish that the cDNA sequence that we cloned is that for ACC-beta.
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Affiliation(s)
- J Ha
- Department of Biochemistry, Purdue University, West Lafayette, IN 47907, USA
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71
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Nada MA, Vianey-Saban C, Roe CR, Ding JH, Mathieu M, Wappner RS, Bialer MG, McGlynn JA, Mandon G. Prenatal diagnosis of mitochondrial fatty acid oxidation defects. Prenat Diagn 1996; 16:117-24. [PMID: 8650121 DOI: 10.1002/(sici)1097-0223(199602)16:2<117::aid-pd820>3.0.co;2-z] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Amniocytes isolated from two pregnancies at risk for fatty acid oxidation defects were incubated with stable isotopically labelled palmitate, in the presence of L-carnitine, to probe that pathway. The labelled acylcarnitines were then quantitated using tandem mass spectrometry. Amniocytes from a pregnancy at risk for medium-chain acyl-CoA dehydrogenase (MCAD) deficiency produced a characteristic acylcarnitine profile with increased levels of octanoylcarnitine and decanoylcarnitine, indicative of MCAD deficiency. DNA analysis confirmed that the fetus was homozygous for the MCAD A985G mutation. Acylcarnitine and DNA analysis of the infant's blood obtained post-partum confirmed MCAD deficiency. Amniocytes from a pregnancy at risk for an unspecified fat oxidation defect produced increased levels of long-chain acylcarnitines consistent with a deficiency in very-long-chain acyl-CoA dehydrogenase (VLCAD). Measurements of the enzymatic activity confirmed VLCAD deficiency in amniocytes. Acylcarnitine profiles of the infant's blood obtained post-partum in addition to enzyme activities measured in fibroblasts confirmed VLCAD deficiency. The successful prenatal diagnosis of VLCAD and MCAD deficiencies using in vitro probes of fatty acid oxidation in fibroblasts suggests that this approach can potentially recognize many mitochondrial fatty acid oxidation defects even if no prior diagnosis is determined in the family at risk.
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Affiliation(s)
- M A Nada
- Metabolic Disease Center, Baylor University Medical Center, Dallas, TX 75246, USA
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72
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Merinero B, Pérez-Cerdá C, Garcia MJ, Gangoiti J, Font LM, Garcia Silva MT, Vianey-Saban C, Duran M, Ugarte M. Mitochondrial very long-chain acyl-CoA dehydrogenase deficiency with a mild clinical course. J Inherit Metab Dis 1996; 19:173-6. [PMID: 8739958 DOI: 10.1007/bf01799422] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Affiliation(s)
- B Merinero
- Dpto. Biología Molecular, Universidad Autónoma de Madrid, Spain
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73
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Andresen BS, Vianey-Saban C, Bross P, Divry P, Roe CR, Nada MA, Knudsen I, Gregersen N. The mutational spectrum in very long-chain acyl-CoA dehydrogenase deficiency. J Inherit Metab Dis 1996; 19:169-72. [PMID: 8739957 DOI: 10.1007/bf01799421] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Affiliation(s)
- B S Andresen
- Center for Medical Molecular Biology, Aarhus University Hospital, Skejby Sygehus, Denmark
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74
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Ogier de Baulny H, Slama A, Touati G, Turnbull DM, Pourfarzam M, Brivet M. Neonatal hyperammonemia caused by a defect of carnitine-acylcarnitine translocase. J Pediatr 1995; 127:723-8. [PMID: 7472823 DOI: 10.1016/s0022-3476(95)70160-5] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Carnitine-acylcarnitine translocase deficiency is a newly recognized inborn error of metabolism that involves transport of long-chain fatty acids into mitochondria, which in turn impairs mitochondrial beta-oxidation, and ketogenesis. We report a new familial example; the affected twins had neonatal distress, hyperammonemia, and transient intracardiac conduction defects. Clinical and biochemical analysis of both our patients and the two previously reported patients revealed that this inherited defect could be manifested during the neonatal period without any of the signs classically associated with fatty oxidation defects. In contrast, all four patients had sustained and "isolated" hyperammonemia, which could be misinterpreted as being caused by urea cycle defects. We conclude that carnitine-acylcarnitine translocase deficiency is a potential differential diagnosis in neonates with unexplained neonatal hyperammonemia. Cardiac and muscle involvement may represent further early pivotal symptoms.
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Affiliation(s)
- H Ogier de Baulny
- Centre d'investigation clinique, Hôpital Robert Debré, Paris, France
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75
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Aoyama T, Souri M, Ushikubo S, Kamijo T, Yamaguchi S, Kelley RI, Rhead WJ, Uetake K, Tanaka K, Hashimoto T. Purification of human very-long-chain acyl-coenzyme A dehydrogenase and characterization of its deficiency in seven patients. J Clin Invest 1995; 95:2465-73. [PMID: 7769092 PMCID: PMC295925 DOI: 10.1172/jci117947] [Citation(s) in RCA: 120] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Mitochondrial very-long-chain acyl-coenzyme A dehydrogenase (VLCAD) was purified from human liver. The molecular masses of the native enzyme and the subunit were estimated to be 154 and 70 kD, respectively. The enzyme was found to catalyze the major part of mitochondrial palmitoylcoenzyme A dehydrogenation in liver, heart, skeletal muscle, and skin fibroblasts (89-97, 86-99, 96-99, and 78-87%, respectively). Skin fibroblasts from 26 patients suspected of having a disorder of mitochondrial beta-oxidation were analyzed for VLCAD protein using immunoblotting, and 7 of them contained undetectable or trace levels of the enzyme. The seven deficient fibroblast lines were characterized by measuring acyl-coenzyme A dehydrogenation activities, overall palmitic acid oxidation, and VLCAD protein synthesis using pulse-chase, further confirming the diagnosis of VLCAD deficiency. These results suggested the heterogenous nature of the mutations causing the deficiency in the seven patients. Clinically, all patients with VLCAD deficiency exhibited cardiac disease. At least four of them presented with hypertrophic cardiomyopathy. This frequency (> 57%) was much higher than that observed in patients with other disorders of mitochondrial long-chain fatty acid oxidation that may be accompanied by cardiac disease in infants.
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Affiliation(s)
- T Aoyama
- Department of Biochemistry, Shinshu University School of Medicine, Matsumoto, Japan
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76
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Abstract
The oxidation of long-chain fatty acids requires a series of enzymes which are located in or on the mitochondrial membranes. These include carnitine palmitoyltransferases I and II, a carnitine-acylcarnitine translocase and, newly discovered, very long-chain acyl-CoA dehydrogenase and the mitochondrial trifunctional protein. These last two chain-shorten acyl-CoA esters to the point where they can be transferred to the more soluble medium- and short-chain-specific enzymes within the mitochondrial matrix. The disorders of long-chain fatty acid oxidation show a rather similar range of clinical and biochemical features, though with different emphasis in the different conditions. Patients with severe defects usually present early with acute attacks of hypoketotic hypoglycaemia and impaired liver function, or with cardiomyopathy or cardiac arrhythmia. In milder variants, skeletal myopathy with intermittent myoglobinuria develops later in life. 3-Hydroxyacyl-CoA dehydrogenase deficiency is unusual in producing peripheral neuropathy and retinitis pigmentosa. Treatment is based on the avoidance of fasting and replacement of normal dietary fat by medium-chain triglyceride, the medium-chain fatty acids entering the mitochondria in a carnitine-independent manner and bypassing the long-chain part of the spiral. Diagnosis must ultimately be based on direct assay of the enzyme involved, but preliminary indicators may come from determination of carnitine and intermediate metabolites in plasma, urinary organic acid profiling, and radioisotopic screening assays with lymphocytes or cultured fibroblasts.
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Affiliation(s)
- R J Pollitt
- Neonatal Screening Laboratory, Children's Hospital, Sheffield, UK
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77
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Fromenty B, Pessayre D. Inhibition of mitochondrial beta-oxidation as a mechanism of hepatotoxicity. Pharmacol Ther 1995; 67:101-54. [PMID: 7494860 DOI: 10.1016/0163-7258(95)00012-6] [Citation(s) in RCA: 442] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Severe and prolonged impairment of mitochondrial beta-oxidation leads to microvesicular steatosis, and, in severe forms, to liver failure, coma and death. Impairment of mitochondrial beta-oxidation may be either genetic or acquired, and different causes may add their effects to inhibit beta-oxidation severely and trigger the syndrome. Drugs and some endogenous compounds can sequester coenzyme A and/or inhibit mitochondrial beta-oxidation enzymes (aspirin, valproic acid, tetracyclines, several 2-arylpropionate anti-inflammatory drugs, amineptine and tianeptine); they may inhibit both mitochondrial beta-oxidation and oxidative phosphorylation (endogenous bile acids, amiodarone, perhexiline and diethylaminoethoxyhexestrol), or they may impair mitochondrial DNA transcription (interferon-alpha), or decrease mitochondrial DNA replication (dideoxynucleoside analogues), while other compounds (ethanol, female sex hormones) act through a combination of different mechanisms. Any investigational molecule should be screened for such effects.
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Affiliation(s)
- B Fromenty
- Institut National de la Santé et de la Recherche Médicale Unité 24, Hôpital Beaujon, Clichy, France
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78
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Pande SV, Murthy MS. Carnitine-acylcarnitine translocase deficiency: implications in human pathology. BIOCHIMICA ET BIOPHYSICA ACTA 1994; 1226:269-76. [PMID: 8054358 DOI: 10.1016/0925-4439(94)90037-x] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- S V Pande
- Laboratory of Intermediary Metabolism, Clinical Research Institute of Montreal, Quebec, Canada
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79
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Abstract
Defects of mitochondrial fatty acid oxidation are recent additions to the catalogue of inherited metabolic diseases. This review focuses upon decent developments in our understanding of the basic biochemistry, clinical presentations and molecular genetics of fatty acid oxidation disorders, with an emphasis on the strategies being used to define new disorders.
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Affiliation(s)
- M J Bennett
- Department of Pathology, University of Texas Southwestern Medical Center, Children's Medical Center of Dallas 75235
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80
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Abstract
OBJECTIVE To review the current understanding of the rapidly changing field of disorders of fatty acid metabolism and to discuss the future directions for research. DESIGN A literature review of the basic biochemistry of the beta-oxidation pathway and clinical cases of defects of fatty acid metabolism are presented, and the diagnosis and treatment of such defects are discussed. MATERIAL AND METHODS In many cases, a correct diagnosis will be made only if these disorders are specifically considered and appropriate tests are obtained, because results of screening tests for other organic acidemias are often normal in these entities. RESULTS The first disorder of fatty acid metabolism was described only 20 years ago. Since then, at least 15 different inborn errors of metabolism that affect beta-oxidation have been identified, most in the past 10 years. Within the past 5 years, investigators have realized that a deficiency of one of these enzymes, medium-chain acyl coenzyme A dehydrogenase, may be one of the most common inborn errors of metabolism. This disorder may have a frequency equal to that of phenylketonuria in some populations in the United States and northern Europe. Approximately 1 to 3% of all unexplained deaths during infancy and childhood are probably related to disorders of beta-oxidation. Diagnosis of these disorders can be difficult because of the intermittent nature of the excretion of characteristic compounds. The mainstay of therapy for defects of beta-oxidation is avoidance of fasting. CONCLUSION All patients with a suspected defect of fatty acid metabolism should be assessed and monitored by a specialist trained in the care of such patients. Continued improvements in the ability to diagnose and treat these disorders will be directly linked to new advances in the basic research on these enzymes. Movements to screen newborns for medium-chain acyl coenzyme A dehydrogenase are under way in some medical centers. Proposed tests include metabolite analysis or direct mutation analysis (or both) from blood spots from newborn screening cards already obtained for every newborn in the United States.
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Affiliation(s)
- J Vockley
- Department of Medical Genetics, Mayo Clinic Rochester, MN 55905
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