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1.
PLoS One ; 13(5): e0196465, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29734388

RESUMO

BACKGROUND: Serum pyridoxal 5'-phosphate (PLP), the active form of vitamin B6, is associated with reduced risk of pancreatic cancer. Data on functional measures of vitamin B6 status and risk of pancreatic cancer is lacking. METHODS: A nested case-control study involving 187 incident cases of pancreatic cancer and 362 individually matched controls were conducted within two prospective cohorts to evaluate the associations between kynurenine metabolites in pre-diagnostic serum samples and risk of pancreatic cancer. RESULTS: Higher serum concentrations of 3-hydroxyanthranilic acid (HAA) and the HAA:3-hydroxykynurenine (HK) ratio (a measure for in vivo functional status of PLP) were significantly associated with reduced risk of pancreatic cancer. Compared with the lowest tertile, odds ratios (95% confidence intervals) of pancreatic cancer for the highest tertile was 0.62 (0.39, 1.01) for HAA, and 0.59 (0.35-0.98) for the HAA:HK ratio, after adjustment for potential confounders and serum PLP (both Ps for trend<0.05). The kynurenine:tryptophan ratio or neopterin was not significantly associated with pancreatic cancer risk. CONCLUSIONS: The inverse association between HAA or the HAA:HK ratio and risk of pancreatic cancer supports the notion that functional status of PLP may be a more important measure than circulating PLP alone for the development of pancreatic cancer.


Assuntos
Ácido 3-Hidroxiantranílico/análise , Cinurenina/análogos & derivados , Cinurenina/metabolismo , Biomarcadores/sangue , Estudos de Casos e Controles , China , Feminino , Humanos , Cinurenina/análise , Cinurenina/sangue , Masculino , Pessoa de Meia-Idade , Razão de Chances , Neoplasias Pancreáticas/metabolismo , Estudos Prospectivos , Fosfato de Piridoxal/sangue , Fatores de Risco , Vitamina B 6/sangue
2.
Appl Microbiol Biotechnol ; 101(17): 6607-6613, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28702795

RESUMO

Trans-2,3-dihydro-3-hydroxyanthranilic acid (DHHA) is a cyclic ß-amino acid that can be used for the synthesis of chiral materials and nonnatural peptides. The aim of this study was to accumulate DHHA by engineering Pseudomonas chlororaphis GP72, a nonpathogenic strain that produces phenazine-1-carboxylic acid and 2-hydroxyphenazine. First, the phzF deletion mutant DA1 was constructed, which produced 1.91 g/L DHHA. Moreover, rpeA and pykF were disrupted and then ppsA and tktA were co-expressed in strain DA1. The resulting strain DA4 increased DHHA concentration to 4.98 g/L, which is 2.6-fold than that of DA1. The effects of the addition of glucose, glycerol, L-tryptophan, and Fe3+on DHHA production were also investigated. Strain DA4 produced 7.48 g/L of DHHA in the culture medium in the presence of 12 g/L glucose and 3 mM Fe3+, which was 1.5-fold higher than the strain in the original fermentation conditions. These results indicate the potential of P. chlororaphis GP72 as a DHHA producer.


Assuntos
Ácido 3-Hidroxiantranílico/análise , Ácido 3-Hidroxiantranílico/metabolismo , Pseudomonas chlororaphis/genética , Pseudomonas chlororaphis/metabolismo , Ácido 3-Hidroxiantranílico/química , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Meios de Cultura/química , Glucose/farmacologia , Engenharia Metabólica/métodos , Transferases de Grupos Nitrogenados/genética , Fenazinas/metabolismo , Pseudomonas chlororaphis/efeitos dos fármacos , Deleção de Sequência
3.
Biosens Bioelectron ; 67: 208-13, 2015 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-25175746

RESUMO

Changing demographics, the rise of personalized medicine and increased identification of biomarkers for diagnosis and management of chronic disease have increased the demand for portable bioanalytical instrumentation and point-of-care. The recent development of molecularly imprinted polymers enables production of low cost and highly stable sensing chips; however, the commercially available and full functional instruments employed for electrochemical analysis have shortcomings in actual homecare applications. In this work, integrated circuits (ICs) for monolithic implementation of voltammeter potentiostat with a large dynamic current range (5 nA to 1.2 mA) and short conversion time (10 ms) were fabricated in a 0.35 µm complementary metal-oxide-semiconductor (CMOS) process. The new instrumentation was tested with molecular imprinted sensors for 3-hydroxyanthranilic acid (3HAA) in urine. The sensor consisted of molecular imprinted of poly(ethylene-co-vinyl alcohol)s (abbreviated as EVALs) for implementation in a flow injection analysis system. The EVAL containing 32 ethylene mol% had the highest imprinting effectiveness for the target molecules. Fit-for-purpose figures of merit were achieved with a limit-of-detection (LOD) of 3.06 pg/mL. The measurements obtained in real undiluted urine samples fell within the reference concentration range of 50-550 ng/mL.


Assuntos
Ácido 3-Hidroxiantranílico/análise , Condutometria/instrumentação , Impressão Molecular/métodos , Polivinil/química , Potenciometria/instrumentação , Urinálise/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Integração de Sistemas
4.
Am J Clin Nutr ; 98(4): 934-40, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24004893

RESUMO

BACKGROUND: Tryptophan metabolism through the kynurenine pathway includes 2 vitamin B-6 [pyridoxal 5'-phosphate (PLP)]-dependent enzymes. We recently showed that plasma 3-hydroxykynurenine (HK) was elevated at low PLP concentrations. OBJECTIVE: We further evaluated and characterized kynurenine-based indexes as possible markers of functional B-vitamin status in plasma. DESIGN: Cross-sectional and longitudinal data were derived from the Western Norway B-vitamin Intervention Trial, including PLP, kynurenine, HK, kynurenic acid (KA), anthranilic acid, xanthurenic acid (XA), and 3-hydroxyanthranilic acid (HAA) measured in plasma at 2 time points. Partial Spearman's correlation, generalized additive models, and receiver operating characteristic (ROC) analysis were used to assess associations of kynurenines with PLP. RESULTS: Ratios HK:XA, HK:HAA, and HK:KA showed markedly stronger negative correlations with PLP than did HK alone (Spearman's ρ = -0.36, -0.29, and -0.31 compared with -0.18, respectively). All associations were nonlinear, with the strongest relation at low PLP. In the ROC analysis, areas under the curve for discriminating low PLP (less than the fifth percentile; 18.6 nmol/L) were 0.78, 0.78, and 0.74, respectively, compared with 0.65 for HK. Oral treatment with 40 mg pyridoxin hydrochloride for 28 d reduced the ratios by up to 60%, with strongest reductions for subjects with low plasma PLP at baseline. Whereas HK was associated with kidney function and several inflammatory markers, such associations were abolished or attenuated for the ratios. CONCLUSION: Plasma values of HK:XA and HK:HAA, which are substrate-product pairs for kynurenine transaminase and kynureninase, respectively, may reflect the intracellular availability of the cofactor (PLP) and, therefore, present as potential markers of functional vitamin B-6 status.


Assuntos
Ácido 3-Hidroxiantranílico/análise , Cinurenina/sangue , Fosfato de Piridoxal/sangue , Deficiência de Vitamina B 6/sangue , Xanturenatos/sangue , Idoso , Envelhecimento/sangue , Biomarcadores/sangue , Estudos Transversais , Feminino , Humanos , Hidrolases/metabolismo , Cinurenina/análogos & derivados , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Noruega , Piridoxina/administração & dosagem , Curva ROC , Transaminases/metabolismo
6.
J Nutr ; 143(7): 1046-51, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23700344

RESUMO

In mammals, nicotinamide (Nam) is biosynthesized from l-tryptophan (l-Trp). The enzymes involved in the initial step of the l-Trp→Nam pathway are l-Trp-2,3-dioxygenase (TDO) and indoleamine-2,3-dioxygenase (IDO). We aimed to determine whether tdo-knockout (tdo(-/-)) mice fed a diet without preformed niacin can synthesize enough Nam to sustain optimum growth. Wild-type (WT) and tdo(-/-) mice were fed a chemically defined 20% casein diet with or without preformed niacin (30 mg nicotinic acid/kg) for 28 d. Body weight, food intake, and liver NAD concentrations did not differ among the groups. In the groups of mice fed the niacin-free diet, urinary concentrations of the upstream metabolites kynurenine (320% increase, P < 0.0001), kynurenic acid (270% increase, P < 0.0001), xanthurenic acid (770% increase, P < 0.0001), and 3-hydroxyanthranilic acid (3-HA; 450% increase, P < 0.0001) were higher in the tdo(-/-) mice than in the WT mice, while urinary concentrations of the downstream metabolite quinolinic acid (QA; 50% less, P = 0.0010) and the sum of Nam and its catabolites (10% less, P < 0.0001) were lower in the tdo(-/-) mice than in the WT mice. These findings show that the kynurenine formed in extrahepatic tissues by IDO and subsequent enzymes can be metabolized up to 3-HA, but not into QA. However, the tdo(-/-) mice sustained optimum growth even when fed the niacin-free diet for 1 mo, suggesting they can synthesize the minimum necessary amount of Nam from l-Trp, because the liver can import blood kynurenine formed in extrahepatic tissues and metabolize it into Nam via NAD and the resulting Nam is then distributed back into extrahepatic tissues.


Assuntos
Niacina/administração & dosagem , Niacinamida/biossíntese , Triptofano Oxigenase/genética , Triptofano/metabolismo , Ácido 3-Hidroxiantranílico/análise , Animais , Peso Corporal , Dieta , Feminino , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Ácido Cinurênico/urina , Cinurenina/urina , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Ácido Quinolínico/urina , Triptofano Oxigenase/deficiência , Triptofano Oxigenase/metabolismo , Xanturenatos/urina
7.
Electrophoresis ; 34(12): 1828-35, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23576119

RESUMO

This article describes the development of a reliable CZE-ESI-MS method to simultaneously separate and quantitate three specific metabolites (3-hydroxyanthranilic acid (3-HAA), quinolinic acid (QA), and picolinic acid (PA)) of the kynurenine pathway (KP) of tryptophan catabolism. Using a covalently bonded sulfonated capillary, the parameters such as pH, type of background electrolyte, type of organic solvent, nebulizer pressure as well as both negative and positive ESI-MS modes were optimized to achieve the best Rs and S/N of three KP metabolites. The developed CZE-ESI-MS assay provided high resolution of PA/QA, high specificity, a total analysis time of 10 min with satisfactory intraday and interday repeatability of migration time and peak areas. Under optimized CZE-ESI-MS conditions, the calibration curves over a concentration range of 19-300 µM for 3-HAA and QA, and 75-300 µM for PA were simultaneously generated. The method was successfully applied for the first time to profile the concentrations of initial substrate, 3-HAA, and its eventual products, PA and QA, formed in the complex multienzyme system. As the ratio of two enzymes, 3-hydroxyanthranilate 3,4-dioxygenase (HAO) and α-amino-ß-carboxymuconate-ε-semialdehyde decarboxylase (ACMSD) decreases, the concentration of QA approaches essentially zero indicating that all ACMS formed by the action of HAO is consumed by ACMSD rather than its spontaneous decay to QA.


Assuntos
Ácido 3-Hidroxiantranílico/análise , Eletroforese Capilar/instrumentação , Eletroforese Capilar/métodos , Complexos Multienzimáticos/química , Ácidos Picolínicos/análise , Ácido Quinolínico/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , 3-Hidroxiantranilato 3,4-Dioxigenase/metabolismo , Ácido 3-Hidroxiantranílico/metabolismo , Tampões (Química) , Carboxiliases/metabolismo , Concentração de Íons de Hidrogênio , Complexos Multienzimáticos/metabolismo , Ácidos Picolínicos/metabolismo , Pressão , Ácido Quinolínico/metabolismo , Reprodutibilidade dos Testes
8.
Clin Exp Immunol ; 173(1): 121-30, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23607723

RESUMO

Circulating neopterin and kynurenine/tryptophan ratio (KTR) increase during inflammation and serve as markers of cellular immune activation, but data are sparse on other determinants of these markers and metabolites of the kynurenine pathway. We measured neopterin, tryptophan, kynurenine, anthranilic acid, kynurenic acid, 3-hydroxykynurenine, 3-hydroxyanthranilic acid and xanthurenic acid in plasma in two age groups, 45-46 years (n = 3723) and 70-72 years (n = 3329). Differences across categories of the potential determinants, including age, gender, renal function, body mass index (BMI), smoking and physical activity, were tested by Mann-Whitney U-test and multiple linear regression including age group, gender, renal function and lifestyle factors. In this multivariate model, neopterin, KTR and most kynurenines were 20-30% higher in the older group, whereas tryptophan was 7% lower. Men had 6-19% higher concentrations of tryptophan and most kynurenines than women of the same age. Compared to the fourth age-specific estimated glomerular filtration rate (eGFR) quartile, the first quartile was associated with higher concentrations of neopterin (25%) and KTR (24%) and 18-36% higher concentrations of kynurenines, except 3-hydroxyanthranilic acid. Additionally, KTR, tryptophan and all kynurenines, except anthranilic acid, were 2-8% higher in overweight and 3-17% higher in obese, than in normal-weight individuals. Heavy smokers had 4-14% lower levels of tryptophan and most kynurenines than non-smokers. Age and renal function were the strongest determinants of plasma neopterin, KTR and most kynurenines. These findings are relevant for the design and interpretation of studies investigating the role of plasma neopterin, KTR and kynurenines in chronic diseases.


Assuntos
Envelhecimento/imunologia , Inflamação/sangue , Ácido 3-Hidroxiantranílico/análise , Idoso , Envelhecimento/sangue , Biomarcadores/sangue , Índice de Massa Corporal , Creatinina/sangue , Feminino , Humanos , Ácido Cinurênico/sangue , Cinurenina/análogos & derivados , Cinurenina/sangue , Masculino , Pessoa de Meia-Idade , Atividade Motora , Neopterina/sangue , Noruega , Valores de Referência , Fumar/sangue , Triptofano/sangue , Xanturenatos/sangue , ortoaminobenzoatos/sangue
9.
Artigo em Inglês | MEDLINE | ID: mdl-22608808

RESUMO

It is highly beneficial to monitor the activity of the kynurenine pathway in a large series of samples with high accuracy and reliability in a single experimental protocol. We have developed a rapid specific solid-phase extraction (SPE)-liquid chromatography-electrospray ionization tandem mass spectrometry method for assaying tryptophan, kynurenine, kynurenic acid (KYNA), 3-hydroxyanthranilic acid (3OHAA), anthranilic acid and quinolinic acid (QA) in rat plasma. We also evaluated picolinic acid (PA) in this method, but it presented with unacceptable validation parameters. The assay involves pre-purification by SPE followed by chromatographic separation by C18 reversed phase chromatography. Mass spectrometric detection was performed using a mass spectrometer in positive and negative electrospray ionization; with a flow rate of 0.2 mL/min and an injection volume of 10 µL. Total run time including sample clean-up was 12 min. The assay method was found to be linear (R² > 0.95) and all the validation parameters were within acceptance range. The developed technique also demonstrated a significant elevation in plasma tryptophan, kynurenine, anthranilic acid and QA, and a significant decrease in KYNA, in rats subjected to post-weaning social isolation rearing, a putative animal model of relevance for depression and schizophrenia. This method can therefore be applied to measure metabolites of the kynurenine pathway in plasma accurately and precisely by LC-MS/MS, thereby helping to realize new opportunities in pharmacological and diagnostic research.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Cinurenina/sangue , Triptofano/sangue , Ácido 3-Hidroxiantranílico/análise , Animais , Carvão Vegetal , Depressão/metabolismo , Ácido Cinurênico/sangue , Cinurenina/metabolismo , Modelos Lineares , Masculino , Ácido Quinolínico/sangue , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Esquizofrenia/metabolismo , Isolamento Social , Extração em Fase Sólida , Espectrometria de Massas em Tandem , Triptofano/metabolismo , ortoaminobenzoatos/sangue
10.
Clin Biochem ; 43(13-14): 1101-6, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20599874

RESUMO

OBJECTIVES: CC-chemokines and kynurenine pathway (KP) metabolites are associated with accelerated atherosclerosis in chronic kidney disease (CKD) patients. DESIGN AND METHODS: We evaluate the plasma levels of anthranilic acid (AA), 3-hydroxyanthranilic acid (3-HAA) and their possible relationship with CC-chemokines, Cu/Zn superoxide dismutase (Cu/Zn SOD) as the marker of oxidative status and high sensitivity C-reactive protein (hsCRP) as an index of inflammation in the population of 48 CKD patients. RESULTS: Compared with controls, CKD patients showed a significant increase in plasma concentrations of CCL2, CCL4, AA, 3-HAA, Cu/Zn SOD and hsCRP. Multiple stepwise regression analysis identified inflammation, renal function and 3-HAA levels as the independent variables significantly associated with increased CCL2; whereas age, 3-HAA and renal function as independent variables associated with CCL4. CONCLUSIONS: These results suggest a relationship between CC-chemokine system and KP activation, which may represent one of the mechanisms involved in the accelerated atherosclerosis in CKD population.


Assuntos
Ácido 3-Hidroxiantranílico/análise , Quimiocina CCL2/sangue , Quimiocina CCL4/sangue , Insuficiência Renal Crônica/sangue , Adulto , Idoso , Aterosclerose/etiologia , Quimiocinas CC , Feminino , Depuradores de Radicais Livres , Humanos , Cinurenina/metabolismo , Masculino , Pessoa de Meia-Idade , Insuficiência Renal Crônica/complicações
11.
Neurochem Int ; 52(6): 1297-303, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18328600

RESUMO

Increased concentrations of kynurenine pathway metabolites have been reported by several groups for disorders involving psychosis, including schizophrenia and bipolar disorder. To identify components of the pathway that may be relevant as biomarkers or may underlie the etiology of psychosis, it is essential to characterize the extent of kynurenine pathway activation and to investigate known regulators of one of the key kynurenine-producing enzymes, tryptophan 2,3-dioxygenase (TDO2), previously shown in this laboratory to be increased commensurate with kynurenine in postmortem anterior cingulate brain tissue from individuals with schizophrenia. Using this same anterior cingulate sample set from individuals with schizophrenia, bipolar disorder, depression and controls (N=12-14 per group), we measured the precursor of kynurenine and two downstream products. The precursor, tryptophan, was significantly increased only in the schizophrenia group (1.54-fold the mean control value, p=0.02), and through substrate-induced activation, may be one cause of the increased kynurenine and kynurenine metabolites. This finding for tryptophan differs from some, but not all, previous reports and methodological reasons for the discrepancies are discussed. A product of kynurenine metabolism, 3-OH-anthranilic acid was also significantly increased only in the schizophrenia group (1.68-fold the mean control value, p=0.03). 3-OH-anthranilic acid is a reactive species with cytotoxic properties, although the threshold for such effects is not known for neurons. Analysis of major pre- and post-mortem variables showed that none were confounding for these between-group experimental comparisons. Nicotinamide, a pathway end product, did not differ between groups but was associated with cause of death (suicide) within the bipolar group (p=0.03).


Assuntos
Transtorno Bipolar/metabolismo , Encéfalo/metabolismo , Cinurenina/metabolismo , Esquizofrenia/metabolismo , Transdução de Sinais/fisiologia , Triptofano/metabolismo , Ácido 3-Hidroxiantranílico/análise , Ácido 3-Hidroxiantranílico/metabolismo , Adulto , Biomarcadores/análise , Biomarcadores/metabolismo , Transtorno Bipolar/diagnóstico , Transtorno Bipolar/fisiopatologia , Encéfalo/fisiopatologia , Cromatografia Líquida de Alta Pressão , Feminino , Giro do Cíngulo/metabolismo , Giro do Cíngulo/fisiopatologia , Humanos , Cinurenina/análise , Pessoa de Meia-Idade , Niacinamida/análise , Niacinamida/metabolismo , Valor Preditivo dos Testes , Esquizofrenia/diagnóstico , Esquizofrenia/fisiopatologia , Suicídio , Triptofano/análise , Triptofano Oxigenase/análise , Triptofano Oxigenase/metabolismo
12.
Epilepsia ; 46 Suppl 5: 49-51, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15987253

RESUMO

PURPOSE: To evaluate the levels of tryptophan and its metabolites along serotonin (5-HT) and kynurenine (KYN) pathways in serum of progressive myoclonus epilepsy (EPM1) patients and cystatin B (CSTB)-deficient mice, a model system for EPM1. METHODS: Tryptophan and its metabolites along serotonin (5-HT) and KYN pathways were determined in serum of EPM1 patients and CSTB-deficient mice by reverse-phase high-pressure liquid chromatography (HPLC) with electrochemical detection. RESULTS: Reduced levels of 5-HT and KYN intermediate metabolite 3-hydroxyanthranilic acid were found in serum of CSTB-deficient mice. A similar trend was found in EPM1 patients. Although tryptophan concentration was reduced in serum of EPM1 patients, no such decrease was observed in CSTB-deficient mice. CONCLUSIONS: The present study demonstrates that tryptophan metabolism along 5-HT and KYN pathways are disrupted in EPM1. Further studies are needed to elucidate the role of KYN pathway in pathogenesis of EPM1.


Assuntos
Ácido 3-Hidroxiantranílico/análise , Cistatinas/deficiência , Modelos Animais de Doenças , Cinurenina/metabolismo , Epilepsias Mioclônicas Progressivas/sangue , Serotonina/sangue , Triptofano/metabolismo , Ácido 3-Hidroxiantranílico/metabolismo , Adulto , Animais , Cromatografia Líquida de Alta Pressão , Cistatina B , Cistatinas/metabolismo , Feminino , Humanos , Masculino , Camundongos , Epilepsias Mioclônicas Progressivas/metabolismo
13.
J Pharm Biomed Anal ; 32(2): 287-93, 2003 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-12763538

RESUMO

Anthranilic acid (ANA) and 3-hydroxyanthranilic acid (3-HANA) have attracted considerable attention as two of the L-tryptophan kynurenine pathway metabolites in the central nervous system. In this study, a highly sensitive and accurate method for the quantification of ANA and 3-HANA has been developed using reversed-phase high performance liquid chromatography (HPLC) with fluorimetric detection. The HPLC assay was carried out using a C(18) column (5 microm, 250 x 4.6 mm i.d.). The mobile phase consisted of a mixture of 25 mM sodium/acetic acid buffer (pH 5.5) and methanol (90:10 v/v). Fluorimetric detection at lambda(ex)=316 nm and lambda(em)=420 nm was used. The assay was applied to the measurement of ANA and 3-HANA acid in rat brain dialysate following administration of L-tryptophan or L-kynurenine. 3-HANA and ANA levels were progressively increased during 90 min following administration of L-tryptophan, then decreased progressively to basal levels. 3-HANA levels were significantly higher than ANA levels after L-kynurenine administration. These findings suggest that the assay developed should provide an improved means for investigation of neurobiology of kynurenine pathway.


Assuntos
Ácido 3-Hidroxiantranílico/análise , Encéfalo/metabolismo , Microdiálise/métodos , ortoaminobenzoatos/análise , Ácido 3-Hidroxiantranílico/metabolismo , Animais , Cromatografia Líquida de Alta Pressão/métodos , Masculino , Ratos , Ratos Sprague-Dawley , ortoaminobenzoatos/metabolismo
14.
Pigment Cell Res ; 12(4): 275-82, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10454296

RESUMO

In order to clarify the cause of ommochrome deficiency in an albino strain of the terrestrial isopod, Armadillidium vulgare, levels of xanthommatin, 3-hydroxykynurenine, 3-hydroxyanthranilic acid and tryptophan in whole body extracts of the albino and the wild type individuals were determined together with enzyme activities of kynurenine-3-hydroxylase, kynureninase and tryptophan-2,3-dioxygenase. Xanthommatin could not be detected in the albinos. The levels of 3-hydroxykynurenine and 3-hydroxyanthranilic acid were determined by high-performance liquid chromatography (HPLC) with electrochemical detection and were markedly low in the albinos compared with the wild type individuals. In contrast to those, the tryptophan levels determined by HPLC with fluorescence detection did not differ significantly between the two phenotypes. In the albino A. vulgare, kynurenine-3-hydroxylase activity was lower and kynureninase activity was higher than in the wild type, although the differences were not statistically significant. Tryptophan-2,3-dioxygenase activity in the albinos was less than 10% that in the wild type. Thus, ommochrome deficiency in the albino A. vulgare is considered to be caused by the extremely low activity of tryptophan-2,3-dioxygenase.


Assuntos
Crustáceos/metabolismo , Fenotiazinas/metabolismo , Pigmentação , Pigmentos Biológicos/deficiência , Xantenos , Ácido 3-Hidroxiantranílico/análise , Ácido 3-Hidroxiantranílico/metabolismo , Aminoácidos/análise , Aminoácidos/metabolismo , Animais , Feminino , Hidrolases/metabolismo , Cinurenina/análogos & derivados , Cinurenina/análise , Cinurenina/metabolismo , Quinurenina 3-Mono-Oxigenase , Masculino , Oxigenases de Função Mista/metabolismo , Oxazinas/análise , Oxazinas/metabolismo , Fenótipo , Pigmentos Biológicos/metabolismo , Fatores Sexuais , Triptofano/análise , Triptofano/metabolismo , Triptofano Oxigenase/metabolismo
15.
Yakugaku Zasshi ; 117(10-11): 657-64, 1997 Nov.
Artigo em Japonês | MEDLINE | ID: mdl-9414579

RESUMO

In tryptophan metabolites, 3-hydroxykynurenine and 3-hydroxyanthranilic acid have been reported to show a carcinogenic action to mice bladder and the relation of the metabolites to human bladder cancer has been discussed. We developed methods for the fluorometric assay of these compounds and showed that the excretion of 3-hydroxyanthranilic acid increased in the patients with bladder cancer. We also devised methods for the fluorometric assay of glucuronide and sulfate of 3-hydroxyanthranilic acid and showed that the minor excretion of these conjugated forms was shown in humans. The distribution of these compounds was also studied and the obtained data suggests that 3-hydroxykynurenine has affinity for the pancreas. We then developed methods for the determination of other metabolites of tryptophan. A fluorescence reaction with UV irradiation was found and applied to the determination. This method is the most sensitive to kynurenic acid but can be applied to kynurenine, nicotinamide and quinolinic acid. Furthermore, this methods also applied to the determination of some medicines, e.g. indomethacin, isoniazid, nalidixic acid, nicorandil and disodium cromoglicate in the serum or urine. We further devised other methods for the determination of xanthurenic acid and 5-hydroxyindoles.


Assuntos
Ácido 3-Hidroxiantranílico/análise , Cinurenina/análogos & derivados , Triptofano/metabolismo , Animais , Fluorometria/métodos , Humanos , Ácido Cinurênico/análise , Cinurenina/análise , Camundongos , Microquímica/métodos , Raios Ultravioleta , Neoplasias da Bexiga Urinária/metabolismo
16.
Graefes Arch Clin Exp Ophthalmol ; 231(8): 482-6, 1993 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8224949

RESUMO

The enzyme indoleamine 2,3-dioxygenase (IDO), which uses free oxygen radicals to cleave the pyrrole ring of indoleamines and give kynurenamines, has previously been found in most tissues, but not in the eye. In this study, IDO activity was measured in post-mortem bovine eyes using Yamazaki's method with L-tryptophan as substrate. Because of the physiological importance of IDO in the protection against free oxygen radical damage, a search was conducted to find this enzyme in the eye. Products of tryptophan degradation by IDO, the kynurenine and 3-hydroxyanthranilic acid were detected and measured in the aqueous humor, iris/ciliary body, and the retina by high-performance liquid chromatography (HPLC) coupled with electrochemical detection. IDO activity was 3.2, 9.0 and 10 nmol/mg protein per h for the aqueous humor, iris/ciliary body, and retina, respectively. These findings suggest that, because of its scavenger properties, IDO is involved in the protection of the eye where, because of its transparency, free radicals are formed not only in the normal oxidation process, but also photochemically.


Assuntos
Humor Aquoso/enzimologia , Retina/enzimologia , Triptofano Oxigenase/metabolismo , Úvea/enzimologia , Ácido 3-Hidroxiantranílico/análise , Animais , Bovinos , Cromatografia Líquida de Alta Pressão , Corpo Ciliar/enzimologia , Indolamina-Pirrol 2,3,-Dioxigenase , Iris/enzimologia , Cinurenina/análise
17.
Anal Biochem ; 200(2): 273-9, 1992 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-1632490

RESUMO

A convenient and rapid method for the simultaneous determination by HPLC of 3-hydroxyanthranilic acid and the dimer derived by its oxidation, cinnabarinic acid, is described. Buffers or biological samples containing these two Trp metabolites were acidified to pH 2.0 and extracted with ethyl acetate with recoveries of 96.5 +/- 0.5 and 93.4 +/- 3.7% for 3-hydroxyanthranilic and cinnabarinic acid, respectively. The two compounds were separated on a reversed-phase (C18) column combined with ion-pair chromatography and detected photometrically or electrochemically. The method was applied successfully to biological systems in which formation of either 3-hydroxyanthranilic or cinnabarinic acid had been described previously. Thus, interferon-gamma-treated human peripheral blood mononuclear cells formed and released significant amounts of 3-hydroxyanthranilic acid into the culture medium and mouse liver nuclear fraction possessed high "cinnabarinic acid synthase" activity. In contrast, addition of 3-hydroxyanthranilic acid to human erythrocytes resulted in only marginal formation of cinnabarinic acid. We conclude that the method described is specific, sensitive, and suitable for the detection of the two Trp metabolites in biological systems.


Assuntos
Ácido 3-Hidroxiantranílico/metabolismo , Eritrócitos/metabolismo , Leucócitos Mononucleares/metabolismo , Oxazinas/sangue , Ácido 3-Hidroxiantranílico/análise , Células Cultivadas , Cromatografia Líquida de Alta Pressão/métodos , Eletroquímica/métodos , Humanos , Interferon gama/farmacologia , Cinética , Leucócitos Mononucleares/efeitos dos fármacos , Proteínas Recombinantes , Espectrofotometria/métodos
18.
Vopr Onkol ; 37(9-10): 925-9, 1991.
Artigo em Russo | MEDLINE | ID: mdl-1842651

RESUMO

A case-control study was performed to evaluate hormonal status in 154 female patients with bladder cancer and 213 healthy women. Cancer patients were characterized by shorter reproductive period and miscarriage, absence of gestation, endometrial and breast cancer and ovarian cysts in the past history. Evaluation of tryptophan metabolism in 131 male and 111 female patients with bladder cancer showed the occurrence of a carcinogenic metabolite--3-oxyanthranilic acid--in the urine to be higher in women. Blood hormone levels were measured in 55 female patients and 49 healthy women by radioimmunoassay. Decreased levels of progesterone and estradiol as well as of hormones potentiating their production (folitropin and lutropin) were the most frequent hormonal disorders encountered.


Assuntos
Carcinoma/epidemiologia , Papiloma/epidemiologia , Neoplasias da Bexiga Urinária/epidemiologia , Ácido 3-Hidroxiantranílico/análise , Adolescente , Adulto , Carcinoma/sangue , Carcinoma/urina , Estudos de Casos e Controles , Estradiol/sangue , Feminino , Gonadotropinas Hipofisárias/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Papiloma/sangue , Papiloma/urina , Progesterona/sangue , Fatores de Risco , Fatores Sexuais , Neoplasias da Bexiga Urinária/sangue , Neoplasias da Bexiga Urinária/urina
19.
J Neurochem ; 55(3): 738-44, 1990 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-2384749

RESUMO

As assessed by HPLC with electrochemical detection, 3-hydroxyanthranilic acid (3-HANA) was found to be present in the rat brain and peripheral organs. The highest concentrations were measured in the kidney (86 fmol/mg of tissue) and spleen (56 fmol/mg of tissue), whereas the adrenal gland, liver, heart, and several forebrain areas (hippocampus, striatum, parietal cortex, thalamus, amygdala/pyriform cortex, and frontal cortex) contained less 3-HANA (between 15 and 22 fmol/mg of tissue). Slightly lower concentrations of 3-HANA were found in the brainstem and the cerebellum. The metabolic disposition of 3-HANA was examined in tissue slices which were incubated in Krebs-Ringer buffer at 37 degrees C in vitro. Incubation for up to 2 h did not affect 3-HANA concentration in brain tissue. However, inhibition of 3-HANA degradation by the specific 3-hydroxyanthranilic acid oxygenase blocker 4-chloro-3-hydroxyanthranilic acid (4-Cl-3-HANA; 10 microM) resulted in a rapid (within 2.5 min) doubling of 3-HANA levels in slices from cerebral cortex. No further increases were observed after incubations of up to 120 min. Exposure of cortical slices to 3-HANA's putative bioprecursors, 3-hydroxykynurenine (3-HK) and anthranilic acid (ANA), in the absence of 4-Cl-3-HANA resulted in rapid, transient increases in 3-HANA production. Maximal 3-HANA synthesis from ANA exceeded the maximal effect of 3-HK by approximately 11-fold.2+ In the presence of 4-Cl-3-HANA, 1 mM ANA produced 9.0 +/- 0.3 and 89.0 +/- 9.3 (5 min) or 51.6 +/- 7.9 and 187.5 +/- 11.2 (120 min) fmol of newly synthesized 3-HANA/mg of brain tissue, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Ácido 3-Hidroxiantranílico/análise , Encéfalo/metabolismo , ortoaminobenzoatos/análise , ortoaminobenzoatos/metabolismo , Ácido 3-Hidroxiantranílico/análogos & derivados , Ácido 3-Hidroxiantranílico/metabolismo , Ácido 3-Hidroxiantranílico/farmacologia , Animais , Química Encefálica , Córtex Cerebral/metabolismo , Cromatografia Líquida de Alta Pressão , Rim/análise , Cinética , Masculino , Oxirredutases/antagonistas & inibidores , Ratos , Ratos Endogâmicos , Baço/análise , Distribuição Tecidual
20.
Biol Chem Hoppe Seyler ; 366(1): 99-102, 1985 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3159398

RESUMO

3-Hydroxyanthranilic acid was identified in lymphocyte cultures during allogeneic stimulation. The metabolite and the synthetic product have identical HPLC retention times, fluorescence spectra, fluorescence intensities as a function of pH value and electrochemical behaviour.


Assuntos
Ácido 3-Hidroxiantranílico/análise , Linfócitos/análise , ortoaminobenzoatos/análise , Cromatografia em Gel , Cromatografia Líquida de Alta Pressão , Eletroquímica , Humanos , Concentração de Íons de Hidrogênio , Teste de Cultura Mista de Linfócitos , Espectrometria de Fluorescência
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