Search PubMedSearch

SEARCH · Search PubMed

Results for “Glutarates”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources

Inhibition of brain glutamate decarboxylase by glutarate, glutaconate, and beta-hydroxyglutarate: explanation of the symptoms in glutaric aciduria?

Glutaric aciduria is a disorcer of lysine, tryptophan, and hydroxylysine metabolism characterized by intermittent metabolic acidemia, dystonia, athetosis and mental retardation. It is due to a recessively inherited deficiency of glutaryl-CoA dehydrogeanse, the enzyme(s) which catalyze the dehydrogenation of glutaryl-CoA to glutaconyl-CoA and decarboxylation of the latter to crotonyl-CoA. Abnormal quantities of glutaric, beta-hydroxyglutaric, and glutaconic acids are found in the urine of these patients. The nature of the movement disorder prompted study of the effects of the abnormally excreted metabolites on brain glutamate decarboxylase, an enzyme implicated in the pathogenesis of Huntington's chorea. Glutamate decarboxylase activity was examined in rat and rabbit brain acetone powders, stabilized with pyridoxal phosphate and glutathione. Glutarate, beta-hydroxyglutarate, and glutaconate were competitive inhibitors of this emzyme, Ki values being 1.3 X 10(-3) mol/l, 2.5 X 10(-4) mol/l, respectively. This inhibition may explain the neurological accompaniments of this syndrome.

Amino Acid Metabolism, Inborn Errors

Odd-Chain Dicarboxylic Acid Feeding Produces a Glutaric Aciduria Type 1-Like Metabolic Signature in Mice.

Glutaric aciduria type-1 (GA1) is an inherited mitochondrial neurometabolic disorder with a poorly understood pathogenesis and unmet medical needs. GA1 can be diagnosed via its hallmark biochemical signature consisting of glutaric aciduria, 3-hydroxyglutaric aciduria, and increased plasma glutarylcarnitine. These glutaryl-CoA-derived metabolites are thought to originate solely in the mitochondria. Here, we demonstrate that wild-type mice fed an 11-carbon odd-chain dicarboxylic acid (undecanedioic acid, DC11) recreate the biochemical phenotype of GA1. Odd-chain dicarboxylic acids like DC11 are not present in food but can arise from several endogenous processes, such as lipid peroxidation and fatty acid ω-oxidation. DC11 is chain-shortened in peroxisomes to glutaryl (DC5)-CoA, which then gives rise to the GA1-like pattern of DC5 metabolites in urine, tissues, and blood. Glutaric acid released from peroxisomes during DC11 chain-shortening can enter mitochondria for reactivation by the enzyme succinyl-CoA:glutarate-CoA transferase (SUGCT) and become substrate for glutaryl-CoA dehydrogenase (GCDH), the enzyme that is deficient in GA1. Our data provide proof-of-concept that the generation of dicarboxylic acids by ω-oxidation, which is stimulated during the same catabolic states known to trigger acute encephalopathy in GA1, may exacerbate disease by increasing the glutaryl-CoA substrate load in mitochondria.

Animals

Fermentative degradation of glutarate via decarboxylation by newly isolated strictly anaerobic bacteria.

Two strains of new strictly anaerobic, gram-negative bacteria were enriched and isolated from a freshwater (strain WoG13) and a saltwater (strain CuG11) anoxic sediment with glutarate as sole energy source. Strain WoG13 formed spores whereas strain CuG11 did not. Both strains were rod-shaped, motile bacteria growing in carbonate-buffered, sulfide-reduced mineral medium supplemented with 2% of rumen fluid. Both strains fermented glutarate to butyrate, isobutyrate, CO2, and small amounts of acetate. With methylsuccinate, the same products were formed, and succinate was fermented to propionate and CO2. No sugars, amino acids or other organic acids were used as substrates. Molar growth yields (Ys) were very small (0.5-0.9 g cell dry mass/mol dicarboxylate). Cells of strain WoG13 contained no cytochromes, and the DNA base ratio was 49.0 +/- 1.4 mol% guanine-plus-cytosine. Enzyme activities involved in glutarate degradation could be demonstrated in cell-free extracts of strain WoG13. A pathway of glutarate fermentation via decarboxylation of glutaconyl-CoA to crotonyl-CoA is suggested which forms butyrate and partly isobutyrate by subsequent isomerization.

Acetates

Glutaric aciduria type II: report on a previously undescribed metabolic disorder.

A report is given on a hitherto undescribed metabolic disorder, characterized clinically by fatal neonatal acidosis, hypoglycemia and a strong 'sweaty-feet' odour. Biochemical features were a massive urinary excretion of glutaric and lactic acids. Isobutyric, isovaleric and alpha-methylbutyric acids were also greatly increased, followed by adipic, ethylmalonic, alpha-hydroxybutyric, n-butyric, beta-hydroxybutyric, sebacic, suberic, propionic, alpha-hydroxyisovaleric and hexanoic acids. The serum level of glutaric acid was highly elevated. In the serum there were also abnormal levels of lactic, alpha-hydroxybutyric, adipic, suberic, p-hydroxyphenyllactic, myristic, hexadecenoic, palmitic, oleic and stearic acids. Plasma lysine and valine were also elevated. Degradation of 14C-labelled glutaric acid and 14C-labelled branched-chain amino acids, alpha-ketoisovaleric and alpha-ketoisocaproic acids in intact fibroblasts was decreased, whereas that of pyruvic acid was normal. The defect was tentatively supposed to be localized at the level of the metabolism of a range of acyl-CoA compounds. The name glutaric aciduria 'type II' is proposed for the patient's disease.

Amino Acids

Glutaric aciduria type I: unusual biochemical presentation.

We describe a patient with glutaryl-coenzyme A dehydrogenase deficiency, demonstrated by a residual enzyme activity of only 1% in cultured fibroblasts. Although the clinical presentation was typical of glutaric aciduria type I, the urine concentrations of glutaric, glutaconic, and 3-hydroxyglutaric acids remained normal, even during episodes of clinical decompensation. An increased free glutarate level was demonstrated only in cerebrospinal fluid.

Carnitine

Glutaric aciduria: clinical and laboratory findings in two brothers.

In two siblings with dystonic cerebral palsy the urinary metabolic profiles of organic acids were dominated by glutaric acid, a metabolite not normally present in urine. The exretion of glutaric acid amounted to several grams per day. The urinary excretion of beta-OH-glutaric acid and glutaconic acid was also enhanced. Imparied metabolism of glutaryl-CoA by leukocytes indicates that the patients suffer from an inborn error of lysine, tryptophan, and hydroxylysine metabolism. A defective oxidation of glutaryl-CoA to crotonyl-CoA, probably due to a deficiency of glutaryl-CoA dehydrogenase, is consistent with these findings.

Amino Acid Metabolism, Inborn Errors

Recurrent hypoglycemia associated with glutaric aciduria type II in an adult.

Repeated episodes of hypoglycemia accompanied by elevated serum concentrations of free fatty acid without ketosis, fatty infiltration of the liver, hepatic dysfunction, and proximal myopathy in a 19-year-old woman, prompted us to analyze her urine for organic acids. Greatly increased quantities of glutaric acid, ethylmalonic acid, dicarboxylic acids with six to 10 carbons, and isovalerylglycine were consistently found in her urine. The ability of cultured skin fibroblasts from the patient to oxidize [1(-14)C]butyrate and [2(-14)C]lysine was reduced. These urinary and in vitro findings indicated defective activity of several acyl coenzyme A dehydrogenases, including glutaryl, isovaleryl, and butyryl coenzyme A dehydrogenases -- establishing a diagnosis of glutaric aciduria Type II. Carnitine concentrations in the skeletal muscle and liver were moderately reduced, but carnitine deficiency was considered a secondary biochemical abnormality. Although glutaric aciduria Type II has previously been described only in a neonate, the disease must be considered in the differential diagnosis of hypoglycemia in adults.

Adult

[Primary photosynthetic reactions in isolated chloroplasts fixed by glutaric aldehyde].

The primary photosynthetic reactions in isolated pea chloroplasts with the structures fixed by increasing concentrations of glutaric aldehyde were studied. It was shown that under chloroplast fixation by 5--25 mM of glutaric aldehyde, a significant inhibition of processes responsible for energy transformation in biological membranes was observed. The highest sensitivity was observed for the phosphorylation reactions, photo-induced changes in absorption at 520 nm, photo-induced quenching of atebrin fluorescence and slow component of delayed light emission. The photo-induced proton uptake was found to be less sensitive to fixation by glutaric aldehyde. It was also shown that on chloroplast fixation the extent of the steady-state P700 oxidation and the lifetime of the photosystem I and II chlorophyll fluorescence are both increased, a fact is indicating of loss in the effectiveness of light energy transfer from the antenna molecules to the reaction centres. Presumably the conformational changes play an essential role at the initial steps of light energy transformation.

Aldehydes

L-Glutaric acidemia: investigation of a patient and his family.

A 5-month-old infant had an unusual combination of clinical signs and symptoms. These consisted of irritability, dystonia, lack of head control, grimacing, opisthotonos, choreoathetoid movements, delayed development, and severe metabolic acidosis. Metabolic investigation by gas-liquid chromatography/mass spectrometry detected urinary organic acids. This confirmed the diagnosis of L-glutaric aciduria. The concentration of L-glutaric acid in the patient's plasma was 2.5 mg/dl (normal range, 0 to 0.1 mg/dl), and in the patient's urine was 4.6 mg/mg of creatinine (normal range, 0 to 0.05 mg/mg of creatinine), but the concentration was not elevated in the plasma and urine of the infant's parents nor of two other family members. No glutaryl-CoA dehydrogenase activity was found in leukocytes taken from the patient. Three of the four family members, including the parents, demonstrated 38%, 42%, and 42% activity, respectively, compared with the activity of normal controls. These findings are consistent with an autosomal recessive disorder involving the metabolism of glutaryl-CoA to crotonyl-Co-a. Dietary restriction was instituted on two separate occasions. First, a low protein diet of 1.6 gm/kg of body weight per day was given, then a low lysine intake of 50 mg/kg/day. These dietary manipulations caused a decrease in the plasma and urine concentrations of L-glutaric acid and beta-hydroxyglutaric acid. However, no effect on the clinical manifestations of the disease was noted.

Amino Acid Metabolism, Inborn Errors

Glutarate semialdehyde dehydrogenase of Pseudomonas. Purification, properties, and relation to L-lysine catabolism.

The lysine-induced glutarate semialdehyde dehydrogenase of Pseudomonas was purified to electrophoretic homogeneity from a mutant strain lacking delta-aminovalerate transaminase. The properties of the enzyme, including molecular weight, amino acid composition, electrophoretic behavior, and kinetic features, distinguish it from similar dehydrogenases induced in the same cell strain by hydroxyproline or by glucarate. Enzyme induction patterns and the growth behavior of a mutant deficient in glutarate semialdehyde dehydrogenase clearly relate this enzyme to the so-called delta-aminovalerate pathway of L-lysine catabolism. Induction studies also indicate that delta-aminovalerate is a better inducer of the dehydrogenase than L-lysine. Cells of a mutant strain lacking delta-aminovalerate transaminase contained higher levels of the dehydrogenase, presumably as a result of the accumulation of delta-aminovalerate, making this mutant a useful preparative source of the enzyme. The marked reduction of lysine-inducible glutarate semialdehyde dehydrogenase in a mutant strain permitted assessment of the basal levels of hydroxyproline/glucarate-inducible ketoglutarate semialdehyde dehydrogenases not possible in wild type cells.

Aldehyde Oxidoreductases

Carrier detection in glutaric aciduria type I using interleukin-2-dependent cultured lymphocytes.

Cultured interleukin 2 (IL-2)-dependent leukocytes from 13 patients with glutaric aciduria type I, 12 obligate carriers, 105 family members and 31 normal controls were assayed for glutaryl-CoA dehydrogenase activity. Of the 13 affected patients, 10 (all Ojibway Indian) had residual enzyme activity (2-13% of control) and 3 patients (all non-Indian) had undetectable enzyme activity. There was partial overlap between the distribution of enzyme activity in obligate heterozygotes and in normal controls (mean values +/- SD: 6.29 +/- 0.94 and 10.75 +/- 2.58 nmol/h per mg protein respectively). Using an arbitrary cutoff level of < 7 nmol/h per mg protein as presumptive evidence of carrier status, the observed frequency of carriers did not differ significantly from that expected from their a priori risk of carrier status. Thirteen per cent of the family members had inconclusive status (activity between 7 and 8.5 nmol/h per mg protein). The method appears suitable for carrier detection, although definitive carrier assignment awaits identification of the mutation(s) responsible for glutaric aciduria type I.

Amino Acid Metabolism, Inborn Errors

Studies on glutaryl-CoA dehydrogenase in leucocytes, fibroblasts and amniotic fluid cells. The normal enzyme and the mutant form in patients with glutaric aciduria.

Three patients with glutaric aciduria have been shown to possess a partial but severe defect of the enzyme glutaryl-CoA dehydrogenase in isolated leucocytes and cultured skin fibroblasts. They could readily be distinguished from heterozygotes by measuring the activity of this enzyme, as shown in a study of the two families involved. The activity of glutaryl-CoA dehydrogenase in normal cultured amniotic fluid cells was comparable to the activity in normal cultured skin fibroblasts indicating the possibility of prenatal diagnosis. Without flavin adenine dinucleotide added to the assay mixture, the activity of glutaryl-CoA dehydrogenase in fibroblasts from normal individuals was very much reduced and similar to the activity in the patients, but after addition of flavin adenine dinucleotide to saturation the activity increased 20-fold in normal subjects while only a very slight increase could be demonstrated in the patients. The Michaelis constant for the substrate glutaryl-CoA was similar for both normal and patient cell lines. The optimum assay conditions for the enzyme in cultured fibroblasts from normal individuals have been established. In contrast to our patients, we found no activity in a fibroblast cell line from a patient with glutaric aciduria diagnosed elsewhere.

Amniotic Fluid

Treatment of glutaryl-CoA dehydrogenase deficiency (glutaric aciduria). Experience with diet, riboflavin, and GABA analogue.

The autosomal recessive inherited disorder glutaryl-CoA dehydrogenase deficiency (glutaric aciduria) runs a progressive course with severe choreoathetosis and dystonia, eventually leading to total helplessness and early death. Theree patients were observed during therapeutic trials with a protein-low diet, riboflavin and GABA analogue. Diet and riboflavin had a slight-to-moderate effect on the clinical symptoms; the excretion of glutaric acid and 2-amino-adipic acid decreased considerably during treatment. Regression of neurologic symptoms was observed during treatment with GABA analogue. It is concluded that the patients should be treated as early as possible with protein-low diet, riboflavin, and GABA analogue.

2-Aminoadipic Acid

Nonpeptide renin inhibitors employing a novel 3-aza(or oxa)-2,4-dialkyl glutaric acid moiety as a P2/P3 amide bond replacement.

A new series of renin inhibitors has been developed. The inhibitors feature a novel replacement for the P2/P3 dipeptide moiety normally associated with renin inhibitors. The dipeptide replacement was a (2S,4S)-3-aza(or oxa)-2,4-dialkylglutaric acid amide. Extensive structure-activity relationship studies determined that optimum potency was achieved when inhibitors employed a benzyl and butyl group at the C(4) and C(2) carbon position, respectively. In addition, maximum in vitro potency was obtained when the N-terminus was functionalized by incorporating a 4-(1,3-dioxabutyl)piperidine amide. SAR data suggested that the 1,3-dioxabutyl group (methoxymethyl ether) interacted by hydrogen bonding to groups in the S4 domain of renin. This hypothesis was strengthened when a 4-butylpiperidine amide was substituted and inhibitor potency decreased dramatically. Inhibitors employing this novel dipeptide mimic were prepared by coupling the glutaric acid amides with either the transition-state mimic (2S,3R,4S)-2-amino-1-cyclohexyl-3,4-dihydroxy-6- methylheptane (18) or the hydroxyethylene dipeptide isostere. The glutaric acid amides were prepared by two general procedures. The first procedure involved the reductive amination of alpha-amino acid esters with alpha-keto esters. The second procedure involved the displacement reaction of alpha-bromo esters or acids with alpha-amino acid amides.

Amides

The allosteric mechanism of bovine liver glutamate dehydrogenase. Evidence from circular-dichroism studies for a conformational change in the ternary complex enzyme-(oxidized nicotinamide-adenine dinucleotide)-glutarate.

1. Computer averaging of multiple scans was used to refine the circular dichroism spectrum of bovine liver glutamate dehydrogenase, revealing well-defined structure in the aromatic region. 2. The circular dichroism of NAD+ bound to glutamate dehydrogenase is strongly negative at 260nm, probably owing to immobilization of the adenosine moiety. Loss of the characteristic adenine-nicotinamide interaction suggests that the coenzyme is bound in an unstacked conformation. 3. Glutarate and succinate, substrate analogues that are both inhibitors competitive with glutamate, do not significantly perturb the circular-dichroism spectrum of the enzyme in the absence of NAD+. 4. In the presence of NAD+, 150nM-succinate decreases the negative circular dichroism corresponding to bound coenzyme, but does not affect the protein circular dichroism. However, ISOmM-glutarate causes profound alternations of the circular-dichroism spectra of the bound NAD+ and of the enzyme, indicative of a protein conformational change. This direct evidence of conformational change specifically promoted by C5 dicarboxylates confirms the previous inference from protection studies. 5. The conformational change is discussed in relation to the allosteric mechanism of glutamate dehydrogenase.

Allosteric Regulation

[Glutaric aciduria type I].

Glutaric aciduria type I is a congenital metabolic disease caused by an enzymatic defect in the degradation of the amino acids lysine and tryptophane. This article presents five Norwegian patients with this condition. Early clinical features may be similar to those of encephalitis. The further clinical course is dominated by choreoathetosis, hyperkinesis and spasticity. The diagnosis is made by tracing enhanced glutaric acid in the urine. The treatment is a low protein diet containing only small quantities of lysine and tryptophane. Four of our patients underwent a neuropsychological examination. Despite the fact that such patients are difficult to test, our examination indicates that the condition has a greater effect on motor than on cognitive functions.

Adolescent

[Glutaric aciduria. 1 new case].

A 4 year old girl with mild mental retardation presented with convulsions, coma and hepatomegaly. She died rapidly. The main biochemical findings were hypoglycaemia, metabolic acidosis, generalised aminoaciduria, elevation of the plasma and urine alpha-amino adipic acid, massive urine excretion of glutaric and glutaconic acids with traces of alpha-hydroxyglutaric acid. The diagnosis of glutaric aciduria was confirmed by the low activity of glutaryl CoA dehydrogenase in liver tissue. This diagnosis should be considered in children with progressive neurological disorders (dystonia, choreoathetosis) and in children with an illness similar to Reye's syndrome.

Amino Acid Metabolism, Inborn Errors