Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:1.3.99.3 (acyl-CoA dehydrogenase)
1,425 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Carnitine levels and acylcarnitine profiles in a patient with mild multiple acyl-CoA dehydrogenase deficient beta-oxidation were compared with control results. Whereas blood and urine total carnitine levels were moderately decreased, blood esterified carnitine levels in the patient were about 2-fold higher than in controls. Urinary acylcarnitine profiles presented with a larger variety of carnitine esters than in controls and included propionylcarnitine, butyrylcarnitine, 2-methylbutyrylcarnitine, hexanoylcarnitine and octanolycarnitine. Total carnitine levels in body fluids were similarly affected by chronic oral L-carnitine administration in patient and controls. By contrast, esterified carnitine level increase was 2-fold more important in controls than in patient. Whereas no qualitative changes in urinary acylcarnitine profiles were induced by L-carnitine therapy in controls, several alterations of these profiles were observed in the patient. The effect of starvation on metabolites was also studied, especially beta-oxidation rates assessed by free fatty acids to 3-hydroxybutyric acid ratios in blood from the patient in the untreated and L-carnitine treated states. In the L-carnitine-supplemented patient, the effect of starvation on the time course of carnitine levels and acylcarnitine profiles could also be documented. The ability of chronic oral L-carnitine administration to remove relatively less important amounts of acylcarnitines in the patient than in controls is further discussed, as well as qualitative alterations of acylcarnitine profiles induced by this therapy in the pathological condition.
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PMID:Acylcarnitine removal in a patient with acyl-CoA beta-oxidation deficiency disorder: effect of L-carnitine therapy and starvation. 885 59

Muscle contraction causes an increase in activity of 5'-AMP-activated protein kinase (AMPK). This study was designed to determine whether chronic chemical activation of AMPK will increase mitochondrial enzymes, GLUT-4, and hexokinase in different types of skeletal muscle of resting rats. In acute studies, rats were subcutaneously injected with either 5-aminoimidazole-4-carboxamide-1-beta-D-ribofuranoside (AICAR; 1 mg/g body wt) in 0.9% NaCl or with 0.9% NaCl alone and were then anesthetized for collection and freezing of tissues. AMPK activity increased in the superficial, white region of the quadriceps and in soleus muscles but not in the deep, red region of the quadriceps muscle. Acetyl-CoA carboxylase (ACC) activity, a target for AMPK, decreased in all three muscle types in response to AICAR injection but was lowest in the white quadriceps. In rats given daily, 1 mg/g body wt, subcutaneous injections of AICAR for 4 wk, activities of citrate synthase, succinate dehydrogenase, and malate dehydrogenase were increased in white quadriceps and soleus but not in red quadriceps. Cytochrome c and delta-aminolevulinic acid synthase levels were increased in white, but not red, quadriceps. Carnitine palmitoyl-transferase and hydroxy-acyl-CoA dehydrogenase were not significantly increased. Hexokinase was markedly increased in all three muscles, and GLUT-4 was increased in red and white quadriceps. These results suggest that chronic AMPK activation may mediate the effects of muscle contraction on some, but not all, biochemical adaptations of muscle to endurance exercise training.
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PMID:Activation of AMP-activated protein kinase increases mitochondrial enzymes in skeletal muscle. 1084 39

A clinical survey of Japanese patients with mitochondrial fatty acid beta-oxidation and related disorders (FAODs) was performed with questionnaires sent to 187 institutions, where inborn errors of metabolism could be managed in Japan, including a search of related literature published between 1985 and 2000. Sixty-four patients with ten types of FAODs were found. Carnitine palmitoyltransferase 2 deficiency and glutaric aciduria type 2 were most common (17 and 14 patients, respectively). As of 2000, there were no patients with medium-chain acyl-CoA dehydrogenase deficiency, which is common in Caucasians. Age at onset was under 2 years in 38 (59%) of the patients. Eight (13%) patients had neonatal onset. Twenty-one (55%) of the 38 children with an initial attack under 2 years of age had acute encephalopathy or a Reye syndrome-like illness. Half of the patients presented within 2 years of birth died or were handicapped. On the other hand, 19 (79%) of the 24 with onset after 2 years of age had muscle symptoms and 23 (96%) of the 24 grew and developed normally. Though the precise incidence of FAODs in Japan is still unknown, as a consequence of the development of diagnostic procedures the number of FAOD cases being diagnosed appears to have increased. Mass screening for FAODs during the neonatal period will greatly aid in prevention of attacks and related effects.
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PMID:A survey of Japanese patients with mitochondrial fatty acid beta-oxidation and related disorders as detected from 1985 to 2000. 1242 13

Carnitine supplementation does not affect carnitine concentrations in tissues of wild-type and very long-chain acyl-CoA dehydrogenase-deficient mice, but results in an increase in long-chain acylcarnitine production.
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PMID:Carnitine supplementation induces long-chain acylcarnitine production--studies in the VLCAD-deficient mouse. 1676 98

Deficiency of very long-chain acyl-CoA dehydrogenase (VLCAD) results in accumulation of C14-C18 acylcarnitines and low free carnitine. Carnitine supplementation is still controversial. VLCAD knockout (VLCAD(+/-)) mice exhibit a similar clinical and biochemical phenotype to those observed in humans. VLCAD(+/-) mice were fed with carnitine dissolved in drinking water. Carnitine, acylcarnitines, and gamma-butyrobetaine were measured in blood and tissues. Measurements were performed under resting conditions, after exercise and after 24 h of regeneration. HepG2 cells were incubated with palmitoyl-CoA and palmitoyl-carnitine, respectively, to examine toxicity. With carnitine supplementation, acylcarnitine production was significantly induced. Nevertheless, carnitine was low in skeletal muscle after exercise. Without carnitine supplementation, liver carnitine significantly increased after exercise, and after 24 h of regeneration, carnitine concentrations in skeletal muscle completely replenished to initial values. Incubation of hepatic cells with palmitoyl-CoA and palmitoyl-carnitine revealed a significantly reduced cell viability after incubation with palmitoyl-carnitine. The present study demonstrates that carnitine supplementation results in significant accumulation of potentially toxic acylcarnitines in tissues. The expected prevention of low tissue carnitine was not confirmed. The principle mechanism regulating carnitine homeostasis seems to be endogenous carnitine biosynthesis, also under conditions with increased demand of carnitine such as in VLCAD-deficiency.
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PMID:Carnitine supplementation induces acylcarnitine production in tissues of very long-chain acyl-CoA dehydrogenase-deficient mice, without replenishing low free carnitine. 1831 32

At present, long-chain fatty acid oxidation (FAO) defects are diagnosed in a number of countries by newborn screening using tandem mass spectrometry. In the majority of cases, affected newborns are asymptomatic at time of diagnosis and acute clinical presentations can be avoided by early preventive measures. Because evidence-based studies on management of long-chain FAO defects are lacking, we carried out a retrospective analysis of 75 patients from 18 metabolic centres in Germany, Switzerland, Austria and the Netherlands with special regard to treatment and disease outcome. Dietary treatment is effective in many patients and can prevent acute metabolic derangements and prevent or reverse severe long-term complications such as cardiomyopathy. However, 38% of patients with very long-chain acyl-CoA dehydrogenase (VLCAD) deficiency had intermittent muscle weakness and pain despite adhering to therapy. Seventy-six per cent of patients with disorders of the mitochondrial trifunctional protein (TFP)-complex including long-chain 3-hydroxyacyl-CoA dehydrogenase (LCHAD) deficiency, had long-term myopathic symptoms. Of these, 21% had irreversible peripheral neuropathy and 43% had retinopathy. The main principle of treatment was a fat-reduced and fat-modified diet. Fat restriction differed among patients with different enzyme defects and was strictest in disorders of the TFP-complex. Patients with a medium-chain fat-based diet received supplementation of essential long-chain fatty acids. l-Carnitine was supplemented in about half of the patients, but in none of the patients with VLCAD deficiency identified by newborn screening. In summary, in this cohort the treatment regimen was adapted to the severity of the underlying enzyme defect and thus differed among the group of long-chain FAO defects.
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PMID:Management and outcome in 75 individuals with long-chain fatty acid oxidation defects: results from a workshop. 1939 38

Body-weight differences in animals may be ascribed to genetic and environmental factors. Here we utilized two divergent porcine genotypes, the highly muscled, leaner PietrianxYorkshire pigs and less muscled, fatter DurocxYorkshire growing pigs (75-110 kg), to examine the role of genetic background on expression of genes associated with anabolic (Fatty acid synthase, FAS; glucose transporter 4, GLUT-4; stearoyl CoA desaturase, SCD; Sterol regulatory binding protein-1, SREBP-1; leptin) and catabolic lipid metabolism (Carnitine palmitoyltransferase-1B, CPT-1B; acyl-CoA dehydrogenase, ACDH) in adipose tissue (AT), liver (L) and skeletal muscle (SKM). Pietrain pigs had lower mRNA abundance for FAS, SREBP-1, SCD and leptin in AT and L, but higher mRNA abundance for L ACDH and SKM ACDH and CPT-1B than Durocs. Duroc pigs exhibited higher expression of FAS, SREBP-1, SCD, leptin in AT and FAS in L and lower expression of ACDH and CPT-1B in L SKM. GLUT-4 expression did not differ in SKM between the two genotypes. Feeding of a beta adrenergic agonist (Paylean) for 52 days lowered expression of lipid anabolic and enhanced lipid catabolic genes expressions similarly in both genotypes. Overall, the lipid metabolism genes differential expression patterns documented here showed that in Pietrain pigs mRNA abundances of synthesis genes were lower and of catabolic genes were higher than in Duroc pigs.
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PMID:Lipid metabolism related gene-expression profiling in liver, skeletal muscle and adipose tissue in crossbred Duroc and Pietrain Pigs. 2048 93

Mitochondrial myopathies commonly present with exercise intolerance typified by breathlessness and fatigue on exercise. In contrast, exercise-induced rhabdomyolysis and myoglobinuria occur rarely. We present a 43-year-old man with a lifelong history of exercise intolerance associated with myalgia and recurrent episodes of exercise-induced myoglobinuria. From early childhood, he had weekly episodes of myoglobinuria, which became infrequent (every 3 months) as an adult. Carnitine transporter defect was suspected, because carnitine levels were low in muscle. During childhood, he was treated with carnitine (4-5 g daily), but without effect. With the advent of acylcarnitines, profiles mimicking but not diagnostic for multiple acyl-CoA dehydrogenase deficiency (MADD) were found. This led to treatment with riboflavin (100 mg/day for 3 years), again without effect. Clinical examination, including echocardiography, revealed no signs of involvement from other organs, and all relatives were asymptomatic.
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PMID:Recurrent myoglobinuria and deranged acylcarnitines due to a mutation in the mtDNA MT-CO2 gene. 2361 64

The 1st International Carnitine Working Group concluded with a round table discussion addressing several areas of relevance. These included the design of future studies that could increase the amount of evidence-based data about the role of carnitine in the treatment of fatty acid oxidation defects, for which substantial controversy still exists. There was general consensus that future trials on the effect of carnitine in disorders of fatty acid oxidation should be randomized, double-blinded, multicentered and minimally include the following diagnoses: medium-chain acyl coenzyme A (CoA) dehydrogenase deficiency, very long-chain acyl-CoA dehydrogenase deficiency, long-chain 3-hydroxyacyl-CoA dehydrogenase deficiency and mitochondrial trifunctional protein deficiency. Another area that generated interest was trials of carnitine in cardiomyopathy and, especially, the use of biomarkers to identify patients at greater risk of cardiotoxicity following treatment with anthracyclines. The possibility that carnitine treatment may lead to improvements in autistic behaviors was also discussed, although the evidence is still not sufficient to make any firm conclusions in this regard. Preliminary data on carnitine levels in children and adolescents with primary hypertension, low birth weight and nephrotic syndrome was also presented. Lastly, the panelists stressed that there remains an objective need to harmonize the terminology used to describe carnitine deficiencies (e.g., primary, secondary and systemic deficiency).
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PMID:Round Table Discussion. 2793 Oct 31

Carnitine transporter defect (CTD; also known as systemic primary carnitine deficiency; MIM 212140) is due to mutations in the SLC22A5 gene and leads to extremely low carnitine levels in blood and tissues. Affected individuals may develop early onset cardiomyopathy, weakness, or encephalopathy, which may be serious or even fatal. The disorder can be suggested by newborn screening. However, markedly low newborn carnitine levels can also be caused by conditions unrelated to CTD, such as the low carnitine levels often associated with normal pregnancies and some metabolic disorders occurring in the mother. In order to clarify the biochemical characteristics most useful for identification of CTD in newborns, we examined California Department of Public Health newborn screening data for CTD from 2005 to 12 and performed detailed chart reviews at six metabolic centers in California. The reviews covered 14 cases of newborn CTD, 14 cases of maternal disorders (CTD, 6 cases; glutaric aciduria, type 1, 5; medium-chain acyl CoA dehydrogenase deficiency, 2; and cobalamin C deficiency, 1), and 154 false-positive cases identified by newborn screening. Our results show that newborns with CTD identified by NBS exhibit different biochemical characteristics, compared to individuals ascertained clinically. Newborns with CTD may have NBS dried blood spot free carnitine near the lower cutoff and confirmatory plasma total and free carnitine levels near the normal lower limit, particularly if obtained within two weeks after birth. These findings raise the concern that true cases of CTD may exist that could have been missed by newborn screening. CTD should be considered as a possible diagnosis in cases with suggestive clinical features, even if CTD was thought to be excluded in the newborn period. Maternal plasma total carnitine and newborn urine total carnitine values are the most important predictors of true CTD in newborns. However, biochemical testing alone does not yield a discriminant rule to distinguish true CTD from low carnitine in newborns due to other causes. Because of this biochemical variability and overlap, molecular genetic testing is imperative to confirm CTD in newborns. Additionally, functional testing of fibroblast carnitine uptake remains necessary for cases in which other confirmatory testing is inconclusive. Even with utilization of all available diagnostic testing methods, confirmation of CTD ascertained by NBS remains lengthy and challenging. Incorporation of molecular analysis as a second tier step in NBS for CTD may be beneficial and should be investigated.
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PMID:Biochemical characteristics of newborns with carnitine transporter defect identified by newborn screening in California. 2871 8


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