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1.
Biol Trace Elem Res ; 2024 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-38703309

RESUMO

Cadmium (Cd) is a serious environmental pollutant affecting various tissues/organs in broilers and compromising their immunological function and productivity. Therefore, the current study aimed to investigate Cd-induced immunotoxicity and potential immunoprotective effect of rutin nanoparticles (RNPs) in the bursal tissue of broilers. A total number of 150 chicks from the Hubbard breed were randomly divided into 5 groups. Group I was fed on standard basal diet (SD) with normal drinking water (DW), Group II received SD containing RNPs (50 mg/kg feed) with DW, Group III fed on SD and DW containing Cd (150 mg/L), Group IV co-treated with rutin-enforced SD (50 mg/kg diet) and DW containing Cd (150 mg/L), and finally, Group V co-supplemented with RNP-enhanced SD (50 mg/kg diet) DW containing Cd (150 mg/L). Productive performance, economic efficiency, oxidative biomarkers, histopathological changes, and the expression level of TLR-4, HSP-70, caspase 3, NF-κB, Bcl-2, and Bax were assessed in the BF tissue. Cd led to severe production and economic losses in exposed birds with a marked surge of oxidative biomarkers, pro-inflammatory cytokines, and histopathological changes in the bursal tissue which could be explained through upregulation of the Hsp70/TLR4/NF-κB molecular pathway in the BF tissue. Meanwhile, RNPs could alleviate most of these changes and prevail optimistic immunomodulatory properties which subsequently could enhance broilers' productivity when incorporated in their diets.

2.
Biomed Pharmacother ; 170: 116080, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38147737

RESUMO

The current study aimed to explore the possible prophylactic and therapeutic effect of Nigella sativa L. oil (NSO) against disruption of endocrine signals and injuries in the thyroid gland, ovary, and uterine tissues induced by sodium fluoride (NaF). Twenty-eight mature female Wistar rats were randomly allocated into four experimental groups (n = 7/group) as follows: control group; NaF group, orally received NaF (20 mg/kg b.wt.) daily; NSO/NaF, orally received NSO (300 mg/kg b.wt.) two weeks before being given NaF and continued throughout the experiment; and NSO+NaF group orally received NSO concurrently with NaF. Our results indicated that NSO restored hormonal balance and suppressed oxidative damage and inflammation. Moreover, the levels of triiodothyronine, thyroxine, thyroid peroxidase, estrogen (E2), progesterone, follicle-stimulating hormone, and luteinizing hormone were elevated, while prostaglandins F2-α and cortisol levels were decreased in NSO treated groups compared to NaF-intoxicated rats. As well, NSO significantly boosted levels of antioxidant molecules, and lowered lipid peroxidation of examined tissues, unlike NaF-treated group. NSO also up-regulated antioxidant enzymes, anti-apoptotic protein, zona pellucida sperm-binding protein, bone morphogenetic protein, and thyroid stimulating hormone, conversely down-regulated inflammatory cytokines, apoptotic proteins, estrogen receptor-α, estrogen receptor-ß, and thyroid stimulating hormone receptors compared to NaF-intoxicated group. Additionally, NSO ameliorated tissue damage of the thyroid gland, ovary, and uterus induced by NaF. -Overall, the prophylactic group (NSO/NaF) performed better antioxidant and anti-inflammatory activities than the treated group almost in all examined tissues, which is reflected by the improvement in the structure of the thyroid, ovarian, and uterine tissues.


Assuntos
Nigella sativa , Glândula Tireoide , Ratos , Feminino , Masculino , Animais , Ratos Wistar , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Ovário , Fluoreto de Sódio/toxicidade , Fluoreto de Sódio/metabolismo , Óleos de Plantas/farmacologia , Estresse Oxidativo , Útero/metabolismo , Receptores de Estrogênio/metabolismo , Sementes
3.
Front Oncol ; 12: 820883, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35265522

RESUMO

Objective: Human endogenous retroviruses (HERVs) make up 8% of the human genome. HERVs are biologically active elements related to multiple diseases. HERV-K, a subfamily of HERVs, has been associated with certain types of cancer and suggested as an immunologic target in some tumors. The expression levels of HERV-K in breast cancer (BCa) have been studied as biomarkers and immunologic therapeutic targets. However, HERV-K has multiple copies in the human genome, and few studies determined the transcriptional profile of HERV-K copies across the human genome for BCa. Methods: Ninety-one HERV-K indexes with entire proviral sequences were used as the reference database. Nine raw sequencing datasets with 243 BCa and 137 control samples were mapped to this database by Salmon software. The differential proviral expression across several groups was analyzed by DESeq2 software. Results: First, the clustering of each dataset demonstrated that these 91 HERV-K proviruses could well cluster the BCa and control samples when the normal controls were normal cells or healthy donor tissues. Second, several common HERV-K proviruses that are closely related with BCa risk were significantly differentially expressed (p adj < 0.05 and absolute log2FC > 1.5) in the tissues and cell lines. Additionally, almost all the HERV-K proviruses had higher expression in BCa tissue than in healthy donor tissue. Notably, we first found the expression of 17p13.1 provirus that located with TP53 should regulate TP53 expression in ER+ and HER2+ BCa. Conclusion: The expression profiling of these 91 HERV-K proviruses can be used as biomarkers to distinguish individuals with BCa and healthy controls. Some proviruses, especially 17p13.1, were strongly associated with BCa risk. The results suggest that HERV-K expression profiles may be appropriate biomarkers and targets for BCa.

4.
Surg Laparosc Endosc Percutan Tech ; 9(6): 423-5, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10872627

RESUMO

Diaphragmatic hernias of the Bochdalek type are rare in adults. The diagnosis may be made with radiography of the chest in an asymptomatic person or in a person with respiratory and/or gastrointestinal symptoms. It has been mistaken for pleural effusion, empyema, lung cysts, and pneumothorax. A 38-year-old woman presented with epigastric pain and a persistent cough of 2 months' duration. A chest radiograph showed bowel loops in the left side of the chest. On laparoscopy, two defects, measuring 10 and 4 cm, respectively, were seen in the left hemidiaphragm. The herniated fundus of the stomach was reduced and the defect repaired with Gore-Tex mesh (W. L. Gore & Associates, Inc., Flagstaff, AZ, U.S.A.). The patient had an uneventful recovery. Laparoscopic repair of the rare Bochdalek hernia is feasible.


Assuntos
Hérnia Diafragmática/cirurgia , Laparoscopia/métodos , Dor Abdominal/diagnóstico por imagem , Dor Abdominal/cirurgia , Adulto , Feminino , Seguimentos , Hérnia Diafragmática/diagnóstico por imagem , Humanos , Radiografia , Telas Cirúrgicas , Resultado do Tratamento
5.
Biochem Mol Med ; 58(1): 46-51, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8809345

RESUMO

Long-chain 3-hydroxyacyl-CoA dehydrogenase (LCHAD) deficiency, an autosomal recessive disorder of fatty-acid oxidation, is clinically characterized by skeletal myopathy, Reye-like syndrome, or sudden unexplained infant death. A common mutation, G1528C, has recently been reported. To avoid nonspecific amplification from a "pseudogene" and potential complications, we have developed a nested PCR/PstI digestion method. Here, we report mutation studies in 11 additional unrelated patients with LCHAD deficiency. Genomic DNA fragments (117 bp) were amplified by the nested PCR, digested with PstI, and subjected to electrophoresis on 12% polyacrylamide gel. Four patients were found to be homozygous for the G1528C mutation; 7 patients were compound heterozygous, indicating significant genetic heterogeneity. The G1528C mutation has been found on at least one allele in all patients with isolated LCHAD deficiency, suggesting that it is an excellent marker for this disease. This DNA test combined with tandem mass-spectrometric in vitro probe analysis easily identifies affected individuals and carriers in families which are compound heterozygous for G1528C.


Assuntos
3-Hidroxiacil-CoA Desidrogenases/deficiência , Análise Mutacional de DNA/métodos , Carnitina/análogos & derivados , Carnitina/sangue , Homozigoto , Humanos , Mutagênese , Reação em Cadeia da Polimerase/métodos
6.
Biochem Mol Med ; 58(1): 59-65, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8809347

RESUMO

Very-long-chain acyl-CoA dehydrogenase (VLCAD) deficiency is a severe defect of mitochondrial fatty acid oxidation characterized by hypertrophic cardiomyopathy, pericardial effusion, steatosis, and hypoglycemia, often resulting in death by 4-5 months of age. The onset of cardiomyopathy and pericardial effusion is insidious and sudden, necessitating early diagnosis and intervention to prevent death. A family affected with this defect is described in which dietary therapy with medium-chain triglycerides (MCT) was associated with rapid reversal of these severe clinical symptoms. Diagnosis by acylcarnitine analysis in the neonatal period can provide the opportunity for early clinical intervention. Prenatal diagnosis from amniocytes by enzymology or in vitro analysis of the fat oxidation pathway with deuterated fatty acid precursors has also been successful and permits intervention at birth. Of 10 affected children, 7 untreated cases died within the first several months while the remaining 3 cases survived when treated with medium-chain triglycerides as the major source of dietary fat.


Assuntos
Acil-CoA Desidrogenase de Cadeia Longa/deficiência , Cardiomiopatias/dietoterapia , Alimentos Infantis , Erros Inatos do Metabolismo Lipídico/complicações , Doença Aguda , Cardiomiopatias/enzimologia , Células Cultivadas , Ácidos Dicarboxílicos/urina , Ácidos Graxos/metabolismo , Feminino , Fibroblastos/enzimologia , Humanos , Lactente , Erros Inatos do Metabolismo Lipídico/dietoterapia , Erros Inatos do Metabolismo Lipídico/enzimologia , Masculino
7.
J Mol Cell Cardiol ; 28(5): 825-33, 1996 May.
Artigo em Inglês | MEDLINE | ID: mdl-8762022

RESUMO

The regulation of fatty acid oxidation in isolated myocytes was examined by manipulating mitochondrial acetyl-CoA levels produced by carbohydrate and fatty acid oxidation. L-carnitine had no effect on the oxidation of [U-14C]glucose, but stimulated oxidation of [1-14C]palmitate in a concentration-dependent manner. L-carnitine (5 mM) increased palmitate oxidation by 37%. The phosphodiesterase inhibitor, enoximone (250 microM), also increased palmitate oxidation by 51%. Addition of L-carnitine to enoximone resulted in a two-fold increase of palmitate oxidation. Whereas, dichloroacetate (DCA, 1 mM), which stimulates PDH activity, decreased palmitate oxidation by 25%. Furthermore, the addition of DCA to myocytes preincubated with either L-carnitine or enoximone, had no effect on the carnitine-induced stimulation of palmitate, and reduced that of enoximone by 50%. Varied concentrations of DCA decreased the oxidation of palmitate and octanoate; but increased glucose oxidation in myocytes. The rate of efflux of acetylcarnitine was highest when pyruvate was present in the medium compared to efflux rates in presence of palmitate or palmitate plus glucose. Although the addition of L-carnitine plus enoximone resulted in a two-fold increase in palmitate oxidation, acetylcarnitine efflux was minimal under these conditions. Acetylcarnitine efflux was highest when pyruvate was present in the medium. These rates were dramatically decreased when myocytes were preincubated with enoximone, despite the stimulation of palmitate oxidation by this compound. These data suggest that: (1) fatty acid oxidation is influenced by acetyl-CoA produced from pyruvate metabolism; (2) L-carnitine may be specific for mitochondrial acetyl-CoA derived from pyruvate oxidation; and (3) it is probable that acetyl-CoA from beta-oxidation of fatty acids is directly channeled into the citric acid cycle.


Assuntos
Acetilcoenzima A/metabolismo , Ácidos Graxos/metabolismo , Glucose/farmacologia , Miocárdio/metabolismo , Acetilcoenzima A/farmacologia , Animais , Carnitina/farmacologia , Células Cultivadas , Glucose/metabolismo , Masculino , Oxirredução/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley
8.
Hum Mol Genet ; 5(4): 461-72, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8845838

RESUMO

Very-long-chain acyl-CoA dehydrogenase (VLCAD) is one of four straight-chain acyl-CoA dehydrogenase (ACD) enzymes, which are all nuclear encoded mitochondrial flavoproteins catalyzing the initial step in fatty acid beta-oxidation. We have used the very fast, Rapid Amplification of cDNA Ends (RACE) based strategy to obtain the sequence of cDNAs encoding human VLCAD from placenta and fibroblasts. Alignment of the predicted amino acid sequence of human VLCAD with those of the other human ACD enzymes revealed extensive sequence homology. Moreover, human VLCAD and human acyl-CoA oxidase showed extensive sequence homology corroborating the notion that these genes are evolutionarily related. Southern blot analysis of genomic DNA from hybrid cell lines was used to localize the VLCAD gene to human chromosome 17p11.2-p11.13105. Using Northern and Western blot analysis to investigate the tissue specific distribution of VLCAD mRNA and protein in several human tissues we showed that VLCAD is most abundant in heart and skeletal muscle. This agrees well with the fact that cardiac and muscle symptoms are characteristic for patients with VLCAD deficiency. Northern blot analysis and sequencing of cloned PCR amplified VLCAD cDNA from four unrelated patients with VLCAD deficiency showed that VLCAD mRNA was undetectable in one patient and that the other three have mutations in both VLCAD alleles. Western blot analysis of patient fibroblasts showed that the identified mutations result in severely reduced amounts of VLCAD protein. None of the patients harbored identical mutations suggesting that the mutational heterogeneity in VLCAD deficiency is large.


Assuntos
Acil-CoA Desidrogenases/genética , Cromossomos Humanos Par 17 , Mutação , Acil-CoA Desidrogenase de Cadeia Longa , Acil-CoA Desidrogenases/deficiência , Sequência de Aminoácidos , Sequência de Bases , Western Blotting , Pré-Escolar , Mapeamento Cromossômico , Clonagem Molecular , Primers do DNA , DNA Complementar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Dados de Sequência Molecular , Homologia de Sequência de Aminoácidos , Distribuição Tecidual
9.
Prenat Diagn ; 16(2): 117-24, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8650121

RESUMO

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.


Assuntos
Acil-CoA Desidrogenase de Cadeia Longa/deficiência , Amniocentese , Erros Inatos do Metabolismo Lipídico/diagnóstico , Mitocôndrias/enzimologia , Acil-CoA Desidrogenase , Acil-CoA Desidrogenase de Cadeia Longa/metabolismo , Hidrolases de Éster Carboxílico/metabolismo , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Erros Inatos do Metabolismo Lipídico/enzimologia , Masculino , Espectrometria de Massas , Oxirredução , Gravidez
11.
J Mol Cell Cardiol ; 27(11): 2465-72, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8596197

RESUMO

The effects of L-carnitine on 14CO2 release from [1-14C]pyruvate oxidation (an index of pyruvate dehydrogenase activity, PDH), [2-14C]pyruvate, and [6-14C]glucose oxidation (indices of the acetyl-CoA flux through citric acid cycle), and [U-14C]glucose (an index of both PDH activity and the flux of acetyl-CoA through the citric acid cycle), were studied using isolated rat cardiac myocytes. L-carnitine increased the release of 14CO2 from [1-14C]pyruvate, and decreased that of [2-14C]pyruvate in a time and concentration-dependent manner. At a concentration of 2.5 mM, L-carnitine produced a 50% increase of CO2 release from [1-14C]pyruvate and a 50% decrease from [2-14C]pyruvate oxidation. L-carnitine also increased CO2 release from [1-14C]pyruvate oxidation by 35%, and decreased that of [2-14C]pyruvate oxidation 30%, in isolated rat heart mitochondria. The fatty acid oxidation inhibitor, etomoxir, stimulated the release of CO2 from both [1-14]pyruvate and [2-14C]pyruvate. These results were supported by the effects of L-carnitine on the CO2 release from [6-14C]- and [U-14C]glucose oxidation. L-carnitine (5 mM) decreased the CO2 release from [6-14C]glucose by 37%, while etomoxir (50 microM) increased its release by 24%. L-carnitine had no effect on the oxidation of [U-14C]glucose. L-carnitine increased palmitate oxidation in a time- and concentration-dependent manner in myocytes. Also, it increased the rate of efflux of acetylcarnitine generated from pyruvate in myocytes. These results suggest that L-carnitine stimulates pyruvate dehydrogenase complex activity and enhances non-oxidative glucose metabolism by increasing the mitochondrial acetylcarnitine efflux in the absence of exogenous fatty acids.


Assuntos
Carnitina/farmacologia , Glucose/metabolismo , Miocárdio/metabolismo , Acetilcarnitina/metabolismo , Animais , Dióxido de Carbono/metabolismo , Células Cultivadas , Relação Dose-Resposta a Droga , Compostos de Epóxi/farmacologia , Hipoglicemiantes/farmacologia , Masculino , Mitocôndrias/metabolismo , Miocárdio/ultraestrutura , Oxirredução , Palmitatos/metabolismo , Complexo Piruvato Desidrogenase/metabolismo , Ratos , Ratos Sprague-Dawley
12.
Biochim Biophys Acta ; 1255(3): 244-50, 1995 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-7734439

RESUMO

This study was conducted to determine if the activity of 2,4-dienoyl-CoA reductase limits the rate of cardiac beta-oxidation of highly unsaturated fatty acids. Although growth hormone treatment of hypophysectomized rats caused a 3-fold increase in the activity of 2,4-dienoyl-CoA reductase, beta-oxidation of docosahexaenoate in cardiomyocytes was not stimulated by this treatment. Since cardiomyocytes oxidized oleic acid more rapidly than docosahexaenoic acid, the utilization of energy did not limit beta-oxidation. Respiration measurements with coupled rat heart mitochondria revealed that the rates of beta-oxidation with palmitoyl-CoA and palmitoylcarnitine as substrates were virtually identical but were 3- to 4-fold higher than the rates obtained with either docosahexaenoyl-CoA or docosahexaenoylcarnitine. Although the activity of carnitine palmitoyltransferase I (CPT I) was 5 times higher with palmitoyl-CoA as substrate than with docosahexaenoyl-CoA, this reaction is only one of several that may limit the beta-oxidation of docosahexaenoic acid. Surprisingly, an incremental inhibition of CPT I resulted in a parallel inhibition of respiration supported by either palmitoyl-CoA or docosahexaenoyl-CoA. This observation agrees with the notion that CPT I may also be a regulatory enzyme in cardiac fatty acid oxidation. It is concluded that the reduction of double bonds by 2,4-dienoyl-CoA reductase does not restrict the cardiac beta-oxidation of highly unsaturated fatty acid, like docosahexaenoic acid.


Assuntos
Ácidos Graxos Insaturados/metabolismo , Miocárdio/metabolismo , Oxirredutases atuantes sobre Doadores de Grupo CH-CH , Animais , Carnitina O-Palmitoiltransferase/metabolismo , Ácidos Docosa-Hexaenoicos/metabolismo , Ácidos Graxos Dessaturases/metabolismo , Hormônio do Crescimento/farmacologia , Masculino , Mitocôndrias Cardíacas/metabolismo , Miocárdio/citologia , Ácido Oleico , Ácidos Oleicos/metabolismo , Ratos , Ratos Sprague-Dawley
13.
Biochem Mol Med ; 54(1): 59-66, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7551818

RESUMO

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.


Assuntos
Acil-CoA Desidrogenases/deficiência , Acil-CoA Desidrogenases/metabolismo , Carnitina/metabolismo , Ácidos Graxos/metabolismo , Acil Coenzima A/metabolismo , Acil-CoA Desidrogenase , Carnitina/análogos & derivados , Fibroblastos/enzimologia , Humanos , Espectrometria de Massas , Oxirredução
14.
J Biol Chem ; 270(2): 530-5, 1995 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-7822275

RESUMO

The accumulation of beta-oxidation intermediates was studied by incubating normal and beta-oxidation enzyme-deficient human fibroblasts with [2H4]linoleate and L-carnitine and analyzing the resultant acylcarnitines by tandem mass spectrometry. Labeled decenoyl-, octanoyl-, hexanoyl-, and butyrylcarnitines were the only intermediates observed with normal cells. Intermediates of longer chain length, corresponding to substrates for the beta-oxidation enzymes associated with the inner mitochondrial membrane, were not observed unless a cell line was deficient in one of these enzymes, such as very-long-chain acyl-CoA dehydrogenase, long-chain 3-hydroxyacyl-CoA dehydrogenase, or electron transfer flavoprotein dehydrogenase. Matrix enzyme deficiencies, such as medium- and short-chain acyl-CoA dehydrogenases, were characterized by elevated concentrations of intermediates corresponding to their respective substrates (octanoyl- and decenoylcarnitines in medium-chain acyl-CoA dehydrogenase deficiency and butyrylcarnitine in short-chain acyl-CoA dehydrogenase deficiency). These observations agree with the notion of intermediate channeling due to the organization of beta-oxidation enzymes in complexes. The only exception is the incomplete channeling from thiolase to acyl-CoA dehydrogenase in the matrix. This situation may be a consequence of only one 3-ketoacyl-CoA thiolase being unable to interact with the several acyl-CoA dehydrogenases in the matrix.


Assuntos
Mitocôndrias/metabolismo , Acil-CoA Desidrogenase , Acil-CoA Desidrogenase de Cadeia Longa , Células Cultivadas , Fibroblastos/enzimologia , Fibroblastos/metabolismo , Humanos , Ácido Linoleico , Ácidos Linoleicos/metabolismo , Oxirredução , Ácido Palmítico , Ácidos Palmíticos/metabolismo
15.
J Inherit Metab Dis ; 18(5): 592-601, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8598640

RESUMO

A new acylcarnitine was observed in the plasma and urine of a patient with isolated 3-methylcrotonyl-CoA carboxylase deficiency. Analysis by tandem mass spectrometry of the methyl ester and butyl ester and their fragment ion spectra identified it as a 3-hydroxy-C5-acylcarnitine. Fibroblasts from a second patient were incubated with deuterium-labelled leucine. Incorporation of label in the new acylcarnitine identified its origin from leucine, and thus confirmed the structure as 3-hydroxyisovalerylcarnitine. The presence of elevated amounts of this metabolite, plus a small amount of 3-methylcrotonylcarnitine in plasma, was diagnostic for isolated 3-methylcrotonyl-CoA carboxylase deficiency. Other conditions in which a hydroxy-C5-acylcarnitine was present were readily differentiated by the abnormal elevation of other acylcarnitines.


Assuntos
Carbono-Carbono Ligases , Carnitina/análogos & derivados , Ligases/deficiência , Carnitina/sangue , Carnitina/urina , Deutério , Feminino , Fibroblastos/enzimologia , Fibroblastos/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Lactente , Leucina/metabolismo , Espectrometria de Massas
16.
Lipids ; 29(7): 517-21, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7968274

RESUMO

The spectrophotometric assay of 2,4-dienoyl coenzyme A (CoA) reductase (EC 1.1.1.34) was modified to improve the linearity and sensitivity of this method. 5-Phenyl-2,4-pentadienoyl-CoA, which has an absorbance maximum at 340 nm with an extinction coefficient of 44,300 M-1 cm-1, was synthesized and used as substrate. This compound is reduced by nicotinamide adenine dinucleotide phosphate (NADPH)-dependent 2,4-dienoyl-CoA reductase to 5-phenyl-3-pentenoyl-CoA. When a tissue homogenate serves as an enzyme source, the product is further metabolized by delta 3, delta 2-enoyl-CoA isomerase (EC 5.3.3.8) to 5-phenyl-2-pentenoyl-CoA, which is hydrated to 5-phenyl-3-hydroxypentanoyl-CoA by enoyl-CoA hydratase (EC 4.2.1.17). The modified assay method, which measures the decrease in absorbance at 340 nm due to the reduction of 5-phenyl-2,4-pentadienoyl-CoA and the oxidation of NADPH, is linear for a longer period of time and is twice as sensitive as the conventional assay with 2,4-decadienoyl-CoA as substrate.


Assuntos
Acil Coenzima A/metabolismo , Ácidos Graxos Dessaturases/análise , Oxirredutases atuantes sobre Doadores de Grupo CH-CH , Animais , Bactérias/enzimologia , Cromatografia Líquida de Alta Pressão , Ácidos Graxos Dessaturases/antagonistas & inibidores , Oxirredução , Ratos , Espectrofotometria , Especificidade por Substrato
18.
Anal Biochem ; 201(1): 62-7, 1992 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-1621963

RESUMO

A radioactive method for assaying 2,4-dienoyl-CoA reductase, also referred to as 4-enoyl-CoA reductase (EC 1.3.1.34), is described. The assay measures the incorporation of tritium from [4B-3H]NADPH into 2-trans,4-cis-decadienoyl-CoA or 2-trans,4-trans-decadienoyl-CoA which, after cleavage of the thioester bond with hydroxylamine, can be separated from the radioactive coenzyme by extraction with toluene. This assay is at least 30 times more sensitive than the spectrophotometric assay, even though rates determined by the radioactive method are 10 times lower than rates obtained spectrophotometrically due to a primary kinetic isotope effect. The linearity of this assay with respect to time and protein concentration is sufficient for determining 2,4-dienoyl-CoA reductase activities in extracts from small samples of human fibroblasts, which were found to contain reductase activities between 1.8 and 5.8 mU/mg of protein.


Assuntos
Ácidos Graxos Dessaturases/análise , Fibroblastos/enzimologia , Oxirredutases atuantes sobre Doadores de Grupo CH-CH , Animais , Bovinos , Células Cultivadas , Humanos , Cinética , Fígado/enzimologia , Contagem de Cintilação , Trítio
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