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1.
Anal Sci ; 37(11): 1541-1546, 2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-33896881

RESUMO

Abnormal levels of biothiols, such as cysteine (Cys), homocystine (Hcy), and glutathione (GSH), are generally known to result in various diseases. A fast dual-responsive OFF-ON fluorescent probe HBO-AC was synthesized and developed. Non-fluorescent HBO-AC can sense Cys by regaining fluorescence at 444 nm within 10 min and a response to GSH by restoring fluorescence at 349 nm within 20 min. There is no mutual interference with Δλ ca. 100 nm. A novel method was developed by utilizing a low reaction rate between HBO-AC and Hcy to eliminate common interference from Hcy. A successful determination of Cys and GSH in fetal bovine serum (FBS) indicated that the probe had potential application for clinical diagnosis. Moreover, it was confirmed that HBO-AC can resist interference from protein to some extent, since FBS was not pretreated before use.


Assuntos
Cisteína , Glutationa , Corantes Fluorescentes , Células HeLa , Homocisteína , Homocistina , Humanos , Espectrometria de Fluorescência
2.
Metabolomics ; 15(7): 103, 2019 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-31289941

RESUMO

INTRODUCTION: We previously developed a tandem mass spectrometry-based label-free targeted metabolomics analysis framework coupled to two distinct chromatographic methods, reversed-phase liquid chromatography (RPLC) and hydrophilic interaction liquid chromatography (HILIC), with dynamic multiple reaction monitoring (dMRM) for simultaneous detection of over 200 metabolites to study core metabolic pathways. OBJECTIVES: We aim to analyze a large-scale heterogeneous data compendium generated from our LC-MS/MS platform with both RPLC and HILIC methods to systematically assess measurement quality in biological replicate groups and to investigate metabolite abundance changes and patterns across different biological conditions. METHODS: Our metabolomics framework was applied in a wide range of experimental systems including cancer cell lines, tumors, extracellular media, primary cells, immune cells, organoids, organs (e.g. pancreata), tissues, and sera from human and mice. We also developed computational and statistical analysis pipelines, which include hierarchical clustering, replicate-group CV analysis, correlation analysis, and case-control paired analysis. RESULTS: We generated a compendium of 42 heterogeneous deidentified datasets with 635 samples using both RPLC and HILIC methods. There exist metabolite signatures that correspond to various phenotypes of the heterogeneous datasets, involved in several metabolic pathways. The RPLC method shows overall better reproducibility than the HILIC method for most metabolites including polar amino acids. Correlation analysis reveals high confidence metabolites irrespective of experimental systems such as methionine, phenylalanine, and taurine. We also identify homocystine, reduced glutathione, and phosphoenolpyruvic acid as highly dynamic metabolites across all case-control paired samples. CONCLUSIONS: Our study is expected to serve as a resource and a reference point for a systematic analysis of label-free LC-MS/MS targeted metabolomics data in both RPLC and HILIC methods with dMRM.


Assuntos
Metaboloma , Metabolômica/métodos , Aminoácidos/metabolismo , Animais , Estudos de Casos e Controles , Linhagem Celular , Cromatografia Líquida de Alta Pressão , Cromatografia de Fase Reversa , Análise por Conglomerados , Homocistina/metabolismo , Humanos , Interações Hidrofóbicas e Hidrofílicas , Redes e Vias Metabólicas , Espectrometria de Massas em Tandem
4.
Nutrients ; 9(1)2016 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-28036059

RESUMO

The objective of this study was to profile plasma amino acids (AA) and derivatives of their metabolism during the periparturient period in response to supplemental rumen-protected methionine (MET) or rumen-protected choline (CHOL). Forty cows were fed from -21 through 30 days around parturition in a 2 × 2 factorial design a diet containing MET or CHOL. MET supply led to greater circulating methionine and proportion of methionine in the essential AA pool, total AA, and total sulfur-containing compounds. Lysine in total AA also was greater in these cows, indicating a better overall AA profile. Sulfur-containing compounds (cystathionine, cystine, homocystine, and taurine) were greater in MET-fed cows, indicating an enriched sulfur-containing compound pool due to enhanced transsulfuration activity. Circulating essential AA and total AA concentrations were greater in cows supplied MET due to greater lysine, arginine, tryptophan, threonine, proline, asparagine, alanine, and citrulline. In contrast, CHOL supply had no effect on essential AA or total AA, and only tryptophan and cystine were greater. Plasma 3-methylhistidine concentration was lower in response to CHOL supply, suggesting less tissue protein mobilization in these cows. Overall, the data revealed that enhanced periparturient supply of MET has positive effects on plasma AA profiles and overall antioxidant status.


Assuntos
Aminoácidos/sangue , Fenômenos Fisiológicos da Nutrição Animal , Carbono/metabolismo , Colina/administração & dosagem , Metionina/administração & dosagem , Aminoácidos Essenciais/sangue , Ração Animal/análise , Animais , Antioxidantes/metabolismo , Bovinos , Colina/sangue , Cistationina/sangue , Cistina/sangue , Dieta/veterinária , Suplementos Nutricionais , Feminino , Homocistina/sangue , Fígado/metabolismo , Metionina/sangue , Metilistidinas/sangue , Parto , Gravidez , Prenhez , Rúmen/metabolismo , Taurina/sangue , Triptofano/sangue
5.
J Stroke Cerebrovasc Dis ; 25(8): 2047-54, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27260368

RESUMO

BACKGROUND AND PURPOSE: Homocysteine (Hcy) is closely associated with stroke. Despite the fact that Hcy has consistently been shown to predict development of recurrent stroke, prior studies on the association of Hcy and stroke subtypes have been inconclusive. METHODS: Data from the Ege Stroke Registry were examined and 5-year follow-up data were analyzed. Multivariate survival analyses were undertaken using Cox proportional hazards models to determine the prognostic value of Hcy in different ischemic stroke subtypes. RESULTS: Of the 9522 patients with stroke, 307 (27%) with hyperhomocysteinemia (hHcy) had recurrent stroke. Univariate Cox regression model showed that hHcy group was associated with recurrent stroke (crude hazard ratio [HR] 1.16; 95% CI 1.02-1.30). But there was no such association in multivariate regression models (adjusted HR 1.11; 95% CI .97-1.26). hHcy was not associated with any ischemic stroke subtypes at 5 years. Univariate Cox regression model showed that hHcy group was associated with overall cardiovascular events (crude HR 1.44; 95% CI 1.32-1.57). However, this association no longer existed in multivariate regression models (adjusted HR 1.01; 95% CI .93-1.12). Higher plasma Hcy group was significantly associated with higher mortality compared with normal plasma Hcy group (OR 1.83; 95% CI .45-2.32). CONCLUSIONS: Our results showed that elevated Hcy is not associated independently with stroke recurrence and overall cardiovascular events in patients with ischemic stroke. There was no association between the hHcy and stroke recurrence in the stroke subtypes within 5 years.


Assuntos
Hiper-Homocisteinemia/complicações , Hiper-Homocisteinemia/epidemiologia , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Eletrocardiografia , Feminino , Homocistina/sangue , Humanos , Hiper-Homocisteinemia/diagnóstico por imagem , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Neuroimagem , Modelos de Riscos Proporcionais , Recidiva , Fatores de Risco , Estatísticas não Paramétricas , Acidente Vascular Cerebral/sangue , Acidente Vascular Cerebral/diagnóstico por imagem , Análise de Sobrevida , Complexo Vitamínico B/uso terapêutico
6.
Cell Mol Neurobiol ; 36(8): 1279-1289, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26825574

RESUMO

Homocysteine (Hcy) is a non-essential amino acid that is derived from the breakdown of dietary methionine. Hyperhomocysteinemia (HHcy) is an independent risk factor for a variety of chronic diseases, especially neurodegenerative conditions. To better understand the role of HHcy in the pathogenesis of neurodegenerative disorders, we investigated the effect of Hcy on the proliferation and activation of microglia Bv2 cells. Cells were treated with six different Hcy concentrations: 0, 50, 100, 300, 500, and 1000 µM for different time periods (8, 12, 16, 24, and 48 h). The morphology of Bv2 cells was observed, and cell activity and proliferation were detected. Cell migration and secretion of pro-inflammatory cytokines were detected by the scratch wound assay, the transwell assay, and ELISA, respectively. The effect of Hcy on Bv2 proliferation occurred earlier (<24 h, especially 16 h) after treatment with concentrations between 100 and 300 µM, and there was no cytotoxicity to Bv2 cells. Meanwhile, functional assays suggested that Hcy not only promoted Bv2 secretion of the pro-inflammatory cytokines IL-1ß, TNF-α, and IL-6, but also enhanced Bv2 migration and invasion, with 100 µM being the most effective concentration. In summary, Bv2 proliferation and activation can be promoted by short-term treatment with low-dose Hcy.


Assuntos
Homocistina/farmacologia , Microglia/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Citocinas/metabolismo , Relação Dose-Resposta a Droga , Microglia/fisiologia , Doenças Neurodegenerativas/etiologia , Doenças Neurodegenerativas/metabolismo
7.
Physiol Int ; 103(4): 428-438, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28229626

RESUMO

This study aimed to assess the role of H2S in homocysteine-induced cardiodynamic effects in the isolated rat heart. The hearts were retrogradely perfused according to the Langendorff technique. The maximum and minimum rates of pressure in the left ventricle (dp/dt max, dp/dt min), systolic and diastolic left ventricular pressures (SLVP, DLVP), heart rate (HR), and coronary flow (CF) were measured. A spectrophotometrical method was used to measure the following oxidative stress markers: index of lipid peroxidation (thiobarbituric acid reactive substances, TBARS), nitrite level (NO2-), superoxide anion radicals (O2•-), and hydrogen peroxide (H2O2) concentrations. The administration of 10 µmol/l DL-homocysteine (DL-Hcy) alone decreased dp/dt max, SLVP, and CF but did not change any oxidative stress parameters. The administration of 10 µmol/l DL-propargylglycine (DL-PAG) decreased all cardiodynamic parameters and increased the concentration of O2•-. The co-administration of DL-Hcy and DL-PAG induced a significant decrease in all estimated cardiodynamic parameters and decreased the concentration of NO2- and O2•- but increased the levels of TBARS and H2O2. Homocysteine shows a lower pro-oxidative effect in the presence of hydrogen sulfide (H2S), which indicates a potential anti-oxidative capacity of H2S.


Assuntos
Coração/efeitos dos fármacos , Homocistina/farmacologia , Sulfeto de Hidrogênio/metabolismo , Miocárdio/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Função Ventricular Esquerda/efeitos dos fármacos , Pressão Ventricular/efeitos dos fármacos , Alcinos/farmacologia , Animais , Circulação Coronária/efeitos dos fármacos , Cistationina gama-Liase/antagonistas & inibidores , Cistationina gama-Liase/metabolismo , Inibidores Enzimáticos/farmacologia , Gasotransmissores , Glicina/análogos & derivados , Glicina/farmacologia , Frequência Cardíaca/efeitos dos fármacos , Peróxido de Hidrogênio/metabolismo , Preparação de Coração Isolado , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Nitritos/metabolismo , Perfusão , Ratos Wistar , Superóxidos/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
8.
J Alzheimers Dis ; 48(2): 443-52, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26402008

RESUMO

Mild cognitive impairment (MCI) may reflect early stages of neurodegenerative disorders such as Alzheimer's disease (AD). Our hypothesis was that cytokeratin 14 (CK14) expression could be used with blood-based biomarkers such as homocysteine, vitamin B12, and folate to identify individuals with MCI or AD from the Australian Imaging, Biomarkers and Lifestyle (AIBL) flagship study of aging. Buccal cells from 54 individuals were analyzed by a newly developed method that is rapid, automated, and quantitative for buccal cell CK14 expression levels. CK14 was negatively correlated with plasma Mg²âº and LDL, while positively correlated with vitamin B12, red cell hematocrit/volume, and basophils in the MCI group and positively correlated with insulin and vitamin B12 in the AD group. The combined biomarker panel (CK14 expression, plasma vitamin B12, and homocysteine) was significantly lower in the MCI (p = 0.003) and AD (p = 0.0001) groups compared with controls. Receiver-operating characteristic curves yielded area under the curve (AUC) values of 0.829 for the MCI (p = 0.002) group and 0.856 for the AD (p = 0.0003) group. These complex associations of multiple related parameters highlight the differences between the MCI and AD cohorts and possibly an underlying metabolic pathology associated with the development of early memory impairment. The changes in buccal cell CK14 expression observed in this pilot study supports previous results suggesting the peripheral biomarkers and metabolic changes are not restricted to brain pathology alone in MCI and AD and could prove useful as a potential biomarker in identifying individuals with an increased risk of developing MCI and eventually AD.


Assuntos
Doença de Alzheimer/sangue , Disfunção Cognitiva/sangue , Queratina-14/metabolismo , Mucosa Bucal/metabolismo , Idoso , Doença de Alzheimer/patologia , Automação Laboratorial/métodos , Biomarcadores/sangue , Cátions Bivalentes/sangue , Bochecha , LDL-Colesterol/sangue , Disfunção Cognitiva/patologia , Estudos de Coortes , Índices de Eritrócitos , Feminino , Homocistina/sangue , Humanos , Magnésio/sangue , Masculino , Microscopia de Fluorescência/métodos , Mucosa Bucal/patologia , Projetos Piloto , Risco , Vitamina B 12/sangue
9.
Carbohydr Res ; 415: 39-47, 2015 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-26279525

RESUMO

The [4-thio]-S-ribosylhomocysteine (SRH) analogs containing substitution of a sulfur atom for the endocyclic oxygen were synthesized by coupling of the 4-thioribose substrates with a thiolate generated from the protected homocysteine. Coupling of the protected 1-deoxy-5-O-mesyl-S-oxo-4-thio-D-ribofuranose with homocysteinate salt gave the C4 epimers of [4-thio]-SRH at the sulfoxide oxidation level lacking a hydroxyl group at anomeric carbon. Treatment of these sulfoxides with BF3⋅Et2O/NaI affected simultaneous reduction to sulfide and global deprotection affording 1-deoxy-4-thio-SRH analog. Treatment of the protected 1-deoxy-S-oxo-4-thio-D-ribofuranose sulfoxide with DAST/SbCl3 resulted in the fluoro-Pummerer rearrangement to give 4-thio-ß-D-ribofuranosyl fluoride. Mesylation of the latter at 5-hydroxyl position followed by coupling with homocysteinate salt and subsequent global deprotection with trifluoroacetic acid afforded [4-thio]-SRH thiohemiacetal.


Assuntos
Homocisteína/análogos & derivados , Homocistina/síntese química , Enxofre/química , Carbono/química , Homocisteína/química , Homocistina/análogos & derivados , Ácido Trifluoracético/química
10.
Stroke ; 45(3): 871-3, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24448992

RESUMO

BACKGROUND AND PURPOSE: Hyperhomocysteinemia is a well-known risk factor for vascular disease. However, its action, mechanism, and role in the acute phase of stroke have not been determined. We tried to determine whether an association existed between elevated serum homocysteine levels and early neurological deterioration (END) in patients with acute ischemic stroke. METHODS: We performed a secondary analysis from the Cilostazol in Acute Ischemic Stroke Treatment (CAIST) trial, which was a double-blinded, randomized, multicenter trial, assessing the noninferiority of cilostazol over aspirin within 48 hours of an acute ischemic stroke. END was defined as an increase of ≥1 point in motor power or an increase of ≥2 points in the total National Institute of Health Stroke Scale score within 7 days. RESULTS: The mean (±SD) serum homocysteine level was 11.4±4.7 µmol/L. Of the 396 patients studied, 57 (14.4%) patients worsened during the 7 days after inclusion. Most (68%) of the END cases occurred within the first 24 hours after treatment. High levels (>10.3 µmol/L) of serum homocysteine were independent predictors for END (third quartile odds ratio, 3.45; 95% confidence intervals, 1.25-9.50; P=0.016; fourth quartile odds ratio, 3.36; 95% confidence intervals 1.18-9.52; P=0.023) in multivariate analysis. CONCLUSIONS: Patients with acute stroke with elevated serum homocysteine levels are at an increased risk for END.


Assuntos
Isquemia Encefálica/patologia , Homocistina/sangue , Sistema Nervoso/patologia , Acidente Vascular Cerebral/patologia , Idoso , Aspirina/uso terapêutico , Biomarcadores/sangue , Proteína C-Reativa/análise , Cilostazol , Progressão da Doença , Método Duplo-Cego , Feminino , Hemoglobina A Glicada/análise , Humanos , Hiper-Homocisteinemia/sangue , Masculino , Pessoa de Meia-Idade , Inibidores da Agregação Plaquetária/uso terapêutico , Valor Preditivo dos Testes , Prognóstico , Modelos de Riscos Proporcionais , Estudos Prospectivos , Fatores de Risco , Tetrazóis/uso terapêutico
11.
J Sep Sci ; 37(1-2): 30-6, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24302617

RESUMO

We have demonstrated for the first time the suitability of fluorosurfactant-capped spherical gold nanoparticles as HPLC postcolumn colorimetric reagents for the direct assay of cysteine, homocysteine, cystine, and homocystine. The success of this work was based on the use of an on-line tris(2-carboxyethyl)phosphine reduction column for cystine and homocystine. Several parameters affecting the separation efficiency and the postcolumn colorimetric detection were thoroughly investigated. Under the optimized conditions, cysteine, homocysteine, cystine, and homocystine in human urine and plasma samples were determined. Detection limits for cysteine, homocysteine, cystine, and homocystine ranged from 0.16-0.49 µM. The accuracy in terms of recoveries ranged between 94.0-102.1%. This proposed method was rapid, inexpensive, and simple.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Cisteína/análise , Cistina/análise , Homocisteína/análise , Homocistina/análise , Cromatografia Líquida de Alta Pressão/instrumentação , Cisteína/sangue , Cisteína/urina , Cistina/sangue , Ouro/química , Homocisteína/sangue , Homocisteína/urina , Homocistina/sangue , Homocistina/urina , Humanos , Nanopartículas/química
12.
J Chin Med Assoc ; 76(11): 611-4, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23933346

RESUMO

BACKGROUND: In recent years, there has been increasing interest in the role of plasma homocysteine (Hcy) as a possible risk factor for several diseases of the central nervous system. The aim of this study was to determine the plasma levels of Hcy in a group of multiple sclerosis (MS) patients from a Greek population and the possible correlation with age, disability status, activity or duration of disease, sex, and treatment. METHODS: The MS group that was studied consisted of 46 patients and a total of 42 healthy individuals served as a control group. Plasma Hcy levels were determined by means of high-performance liquid chromatography coupled with fluorescence detection, after precolumn derivatization with 4-Fluoro-7-aminosulfonylbenzofurazan (ABD-F). RESULTS: Statistical analysis revealed that, in the MS patients, Hcy levels were not significantly different as compared to those in the controls. Men presented with higher Hcy levels than women in the MS group; however, age, disease subtype, disease duration, relapse rate, and Expanded Disability Status Scale score/Multiple Sclerosis Severity Score did not significantly affect Hcy levels in MS patients. CONCLUSION: The preliminary data suggest that Hcy levels were not elevated in our sample of Greek MS patients, which does not support previous findings of a significant correlation between elevated serum Hcy levels and MS. Further studies to establish a possible association between MS and Hcy levels in the context of different ethnic groups with different habits are needed.


Assuntos
Homocistina/sangue , Esclerose Múltipla/sangue , Adulto , Feminino , Grécia , Humanos , Masculino
13.
Zhonghua Er Ke Za Zhi ; 51(3): 194-8, 2013 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-23751581

RESUMO

OBJECTIVE: Combined methylmalonic acidemia with homocystinuria is a common form of methylmalonic acidemia in China. Patients with this disease can progress to death without timely and effective treatment. This study aimed to analyze the treatment outcomes of patients with combined methylmalonic acidemia and homocystinuria. METHOD: From September 2004 to April 2012, 58 patients with combined methylmalonic acidemia and homocystinuria (34 males and 24 females) were diagnosed and treated in our hospital. Fifty cases were from clinical patients including 42 early-onset cases and 8 late-onset cases. Their age when they were diagnosed ranged from 18 days to 30.8 years. The other 8 cases were from newborn screening. All the patients were treated with vitamin B12, betaine, folic acid, vitamin B6, and L-carnitine. The physical and neuropsychological development, general laboratory tests, the levels of amino acids, acylcarnitines, and homocysteine in blood, and organic acids in urine were followed up. RESULT: The follow-up period ranged from 1 month to 7.1 years. Three cases died (all were early-onset cases). In the other patients after treatment, the symptoms such as recurrent vomiting, seizures, lethargy, and poor feeding disappeared, muscle strength and muscle tension were improved, and general biochemical abnormalities such as anemia and metabolic acidosis were corrected. Among the surviving 55 cases, 49 had neurological impairments such as developmental delay and mental retardation. The median levels of blood propionylcarnitine and its ratio with acetylcarnitine, serum homocysteine, and urine methylmalonic acid were significantly decreased (P < 0.01), from 7.73 µmol/L (ranged from 1.5 to 18.61 µmol/L), 0.74 (ranged from 0.29 to 2.06), 97.3 µmol/L (ranged from 25.1 to 250 µmol/L) and 168.55 (ranged from 3.66 to 1032.82) before treatment to 2.74 µmol/L (ranged from 0.47 to 12.09 µmol/L), 0.16 (ranged from 0.03 to 0.62), 43.8 µmol/L (ranged from 17 to 97.8 µmol/L) and 6.81 (ranged from 0 to 95.43) after treatment, respectively. CONCLUSION: Patients with combined methylmalonic acidemia and homocystinuria respond to a combined treatment consisting of supplementation of hydroxycobalamin, betaine, folic acid, vitamin B6 and L-carnitine with clinical and biochemical improvement. But the long-term outcomes are unsatisfactory, with neurological sequelae in most patients.


Assuntos
Erros Inatos do Metabolismo dos Aminoácidos/terapia , Homocistinúria/terapia , Hidroxocobalamina/uso terapêutico , Vitamina B 12/uso terapêutico , Adolescente , Adulto , Erros Inatos do Metabolismo dos Aminoácidos/sangue , Erros Inatos do Metabolismo dos Aminoácidos/diagnóstico , Betaína/administração & dosagem , Betaína/uso terapêutico , Carnitina/análogos & derivados , Carnitina/sangue , Criança , Pré-Escolar , Feminino , Seguimentos , Homocistina/sangue , Homocistinúria/sangue , Homocistinúria/diagnóstico , Humanos , Hidroxocobalamina/administração & dosagem , Lactente , Recém-Nascido , Masculino , Ácido Metilmalônico/urina , Triagem Neonatal , Resultado do Tratamento , Vitamina B 12/administração & dosagem , Deficiência de Vitamina B 12/congênito , Adulto Jovem
14.
J Pept Sci ; 19(5): 263-7, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23532793

RESUMO

Methodology for the rapid N-acylation of aminothiols in aqueous solution using procedures commonly employed in biochemical studies is described here. Glutathione disulfide (GSSG) and homocystine were diN-acetylated in ~100% yield in 0.1 M aqueous NaHCO3 (pH 8.5) at room temperature by 2.5 equiv of the activated ester, N-hydroxysulfosuccinimidyl acetate, an efficient water-soluble acetylating reagent. Following acetone precipitation, diN-acetylGSSG was further purified and desalted on a strong anion-exchange (SAX) cartridge. DiN-acetylhomocystine was simultaneously purified and desalted on a C18 cartridge. The N-acetylated aminothiols were generated using gel-immobilized tris(2-carboxyethyl)phosphine as a reductant, which obviated the need for further purification. Alternatively, disulfide exchange with dissolved dithiothreitol yielded N-acetylglutathione, which was purified on the SAX cartridge. pH titrations of N-acetylglutathione (8.99) and N-acetylhomocysteine (9.66) as well as those of commercially available N-acetylcysteine (9.53) and N-acetylpenicillamine (10.21) yielded pK(a) (SH) values of importance for biological studies.


Assuntos
Acilação , Glutationa/análogos & derivados , Homocisteína/análogos & derivados , Compostos de Sulfidrila/química , Ditiotreitol/química , Glutationa/química , Dissulfeto de Glutationa/química , Homocisteína/química , Homocistina/química , Concentração de Íons de Hidrogênio , Soluções/química , Água/química
15.
PLoS One ; 8(3): e57305, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23505425

RESUMO

The burden of stroke is disproportionately high in the South Asian subcontinent with South Asian ethnicity conferring a greater risk of ischemic stroke than European ancestry regardless of country inhabited. While genes associated with stroke in European populations have been investigated, they remain largely unknown in South Asians. We conducted a comprehensive meta-analysis of known genetic polymorphisms associated with South Asian ischemic stroke, and compared effect size of the MTHFR C677T-stroke association with effect sizes predicted from homocysteine-stroke association. Electronic databases were searched up to August 2012 for published case control studies investigating genetic polymorphisms associated with ischemic stroke in South Asians. Pooled odds ratios (OR) for each gene-disease association were calculated using a random-effects model. We identified 26 studies (approximately 2529 stroke cases and 2881 controls) interrogating 33 independent genetic polymorphisms in 22 genes. Ten studies described MTHFR C677T (108 with TT genotype and 2018 with CC genotype) -homocysteine relationship and six studies (735 stroke cases and 713 controls) described homocysteine-ischemic stroke relationship. Risk association ORs were calculated for ACE I/D (OR 5.00; 95% CI, 1.17-21.37; p = 0.03), PDE4D SNP 83 (OR 2.20; 95% CI 1.21-3.99; p = 0.01), PDE4D SNP 32 (OR 1.57; 95% CI 1.01-2.45, p = 0.045) and IL10 G1082A (OR 1.44; 95% CI, 1.09-1.91, p = 0.01). Significant association was observed between elevated plasma homocysteine levels and MTHFR/677 TT genotypes in healthy South Asians (Mean difference (ΔX) 5.18 µmol/L; 95% CI 2.03-8.34: p = 0.001). Our results demonstrate that the genetic etiology of ischemic stroke in South Asians is broadly similar to the risk conferred in Europeans, although the dataset is considerably smaller and warrants the same clinical considerations for risk profiling.


Assuntos
Grupo com Ancestrais do Continente Asiático/genética , Predisposição Genética para Doença , Polimorfismo Genético , Acidente Vascular Cerebral/genética , Ásia Sudeste , Estudos de Casos e Controles , Nucleotídeo Cíclico Fosfodiesterase do Tipo 3/genética , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4 , Estudos de Associação Genética , Homocistina/sangue , Humanos , Interleucina-10/genética , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Peptidil Dipeptidase A/genética , Fenótipo , Polimorfismo de Nucleotídeo Único , Acidente Vascular Cerebral/metabolismo
16.
Int J Vitam Nutr Res ; 82(1): 41-52, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22811376

RESUMO

Homocysteine (HCY), C-reactive protein (hsCRP), and triglycerides (TG) are risk factors for cardiovascular disease (CVD). While multivitamins (MVit) may reduce HCY and hsCRP, omega-3 fatty acids (N3) reduce TG; yet, they are seldom studied simultaneously. We randomly assigned 100 participants with baseline HCY (> 8.0 umol/L) to the daily ingestion of: (1) placebo, (2) MVit (VitC: 200 mg; VitE: 400 IU; VitB6: 25 mg; Folic Acid: 400 ug; VitB12: 400 ug) + placebo, (3) N3 (2 g N3, 760 mg EPA, 440 mg DHA)+placebo, or (4) MVit + N3 for 12 weeks. At follow-up, we observed significant reductions in HCY (umol/L) for the MVit (- 1.43, 95 %CI, - 2.39, - 0.47) and MVit + N3 groups (- 1.01, 95 %CI, - 1.98, - 0.04) groups, both being significant (p < 0.05) vs. placebo (- 0.57, 95 %CI, - 1.49, 0.35) and N3 (1.11, 95 % CI, 0.07, 2.17). hsCRP (nmol/L) was significantly reduced in the MVit (- 6.00, 95 %CI, - 1.04, - 0.15) and MVit + N3 (- 0.98, 95 %CI, - 1.51, - 0.46) groups, but not vs. placebo (- 0.15, 95 %CI, - 0.74, 0.43) or N3 (- 0.53, 95 %CI, - 1.18, 0.12). Lastly, we observed significant reductions in TG for the N3 (- 0.41, 95 %CI, - 0.69, - 0.13) and MVit + N3 (- 0.71, 95 %CI, - 0.93, - 0.46) groups, both significant vs. placebo (- 0.10, 95 %CI, - 0.36, 0.17) and MVit groups (0.15, 95 %CI, - 12, 0.42). The co-ingestion of MVit + N3 provides synergistic affects on HCY, hsCRP, and plasma TG.


Assuntos
Ácidos Graxos Ômega-3/administração & dosagem , Homocistina/sangue , Vitaminas/administração & dosagem , Adulto , Idoso , Proteína C-Reativa/análise , Suplementos Nutricionais , Feminino , Humanos , Lipoproteínas LDL/sangue , Masculino , Pessoa de Meia-Idade , Triglicerídeos/sangue , Vitaminas/sangue
17.
Neurosciences (Riyadh) ; 17(3): 219-25, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22772926

RESUMO

OBJECTIVE: To determine the relation between maternal Helicobacter pylori (H. pylori) infection and the occurrence of neural tube defects (NTDs) in newborns. METHODS: This hospital-based case-control study was carried out in Dezyani Teaching Hospital, Gorgan, Northern Iran from April 2007 to March 2009. Thirty-five mothers with NTD-affected newborns, and 53 mothers with healthy newborns were considered the cases and controls. A peripheral blood sample was obtained from all subjects, and H. pylori infections were tested by H. pylori serum antibody. The serum folic acid, vitamin B12, ferritin, and homocysteine concentrations were measured by laboratory tests. Data were analyzed using odds ratio (OR) and logistic regression. RESULTS: Forty-three percent of cases, and 26% of controls were positive for H. pylori IgG antibody, and this difference was not significant. The H. pylori seropositivity non significantly increased the risk of NTD-affected pregnancies (OR: 2.08; 95% confidence interval [CI]: 0.84-5.17, p=0.11). Serum vitamin B12 deficiency was detected in 17% of cases and 13% of controls, and folic acid deficiency in 17% of cases and 13% of controls (p=0.61). The H. pylori seropositivity was non significantly associated with low serum folate (OR 1.93 CI: 0.58-6.4, p=0.34) and ferritin (OR 1.24; CI: 0.42-3.60, p=0.68). CONCLUSION: Maternal H. pylori infection can increase the risk of occurrence of NTDs in newborns.


Assuntos
Infecções por Helicobacter/epidemiologia , Defeitos do Tubo Neural/epidemiologia , Efeitos Tardios da Exposição Pré-Natal/epidemiologia , Proteínas de Bactérias/imunologia , Estudos de Casos e Controles , Feminino , Ferritinas/sangue , Ácido Fólico/sangue , Infecções por Helicobacter/sangue , Homocistina/sangue , Humanos , Imunoglobulina G/sangue , Recém-Nascido , Modelos Logísticos , Masculino , Defeitos do Tubo Neural/sangue , Irlanda do Norte/epidemiologia , Razão de Chances , Gravidez , Efeitos Tardios da Exposição Pré-Natal/sangue , Estudos Retrospectivos , Fatores de Risco , Vitamina B 12/sangue , Adulto Jovem
18.
Eur J Pharm Sci ; 47(1): 117-23, 2012 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-22659373

RESUMO

The dyslipidemia control through lipid lowering therapy is one of the targets for the treatment of CKD. By this pilot study we aimed to evaluate the effect of hypolipidemic drugs on the levels of low molecular weight (LMW) thiols bound to LDL in nephropatic patients. We enrolled thirty CKD randomized to receive three different hypolipidemic regimens: simvastatin alone (40 mg/day) or ezetimibe/simvastatin combined therapy (10/20 or 10/40 mg/day). LMW thiols in their reduced and total form, oxidative stress indices as malondialdehyde and allantoin/uric acid ratio were evaluated. LDL thiolation decreased in all treated patients, but a greater efficacy was attained from a combined therapy with a higher simvastatin dose, by which a 31% decrease of all S-bound thiols was reached after 1 year of therapy. In particular, in this patients group the reduction of apoB-Hcy was greater than 40%. The concomitant decrease of the oxidative stress indices during the therapy brings to the hypothesis that decreased levels of protein bound thiols may be a consequence of oxidative stress improvement. Therefore lipid lowering therapy may have beneficial effects also through the reduction of LDL-S-homocysteinylation that has been reported to have antiangiogenic and proatherogenic effect on endothelial vascular cells.


Assuntos
Azetidinas/uso terapêutico , LDL-Colesterol/metabolismo , Hipolipemiantes/uso terapêutico , Insuficiência Renal Crônica/tratamento farmacológico , Insuficiência Renal Crônica/metabolismo , Sinvastatina/uso terapêutico , Alantoína/metabolismo , Apolipoproteínas B/metabolismo , Combinação de Medicamentos , Dislipidemias/tratamento farmacológico , Dislipidemias/metabolismo , Combinação Ezetimiba e Simvastatina , Feminino , Homocistina/metabolismo , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , Malondialdeído/metabolismo , Pessoa de Meia-Idade , Estresse Oxidativo/efeitos dos fármacos , Projetos Piloto , Compostos de Sulfidrila/metabolismo , Ácido Úrico/metabolismo
19.
J Nutr Health Aging ; 16(4): 395-400, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22499465

RESUMO

OBJECTIVES: The studies were carried out on 36 growing albino Wistar rats. PARTICIPANTS/MEASUREMENTS: The animals were randomly divided into six equinumerous groups (six rats per group), and were fed six different diets for 42 days. The control group (I) was fed with AIN-93G semi-synthetic diet, whereas groups II-VI were fed with AIN-93G semi-synthetic diet supplemented with: 2, 4, 8, 16 and 32 g of methionine/kg diet, respectively. There were assessed enzymatically, in rats' blood serum, the contents of homocysteine, total cholesterol, HDL fraction and triacyloglicerols. In addition, the LDL+VLDL cholesterol content was calculated. RESULTS: The methionine content of the diet was found to be highly positively correlated with the homocysteine content (r = 0.981) and negatively correlated with the triacylglycerols content (r = -0.916) of the experimental animals' blood serum. CONCLUSION: In the blood serum of rats fed the highest-methionine diet (32 g methionine/kg diet), the homocysteine content was significantly higher, as were the levels of total cholesterol and its HDL fraction, while the triacylglycerols content was lower as compared to the values obtained for rats fed other diet types.


Assuntos
Dieta , Suplementos Nutricionais , Homocistina/sangue , Metionina/administração & dosagem , Triglicerídeos/sangue , Animais , HDL-Colesterol/sangue , LDL-Colesterol/sangue , VLDL-Colesterol/sangue , Ratos , Ratos Wistar
20.
Bioelectrochemistry ; 86: 9-21, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22296821

RESUMO

The modification of glassy carbon (GC) electrode with electrodeposited nickel oxide nanoparticles (NiOxNPs) and deoxyribonucleic acid (DNA) is utilized as a new efficient platform for entrapment of osmium (III) complex. Surface morphology and electrochemical properties of the prepared nanocomposite modified electrode (GC/DNA/NiOxNPs/Os(III)-complex) were investigated by FESEM, cyclic voltammetry and electrochemical impedance spectroscopy techniques. Cyclic voltammetric results indicated the excellent electrocatalytic activity of the resulting electrode toward oxidation of l-cysteine (CySH) at reduced overpotential (0.1 V vs. Ag/AgCl). Using chronoamperometry to CySH detection, the sensitivity and detection limit of the biosensor are obtained as 44 µA mM(-1) and 0.07 µM with a concentration range up to 1000 µM. The electrocatalytic activity of the modified electrode not only for oxidation of low molecular-mass biothiols derivatives such as, glutathione, l-cystine, l-methionine and electroactive biological species ( dopamine, uric acid, glucose) is negligible but also for very similar biothiol compound (homocysteine) no recognizable response is observed at the applied potential window. Furthermore, the simultaneous voltammetric determination of l-cysteine and homocysteine compounds without any separation or pretreatment process was reported for the first time in this work. Finally, the applicability of sensor for the analysis of CySH concentration in complex serum samples was successfully demonstrated. Highly selectivity, excellent electrocatalytic activity and stability, remarkable antifouling property toward thiols and their oxidation products, as well as the ability for simultaneous detection of l-cysteine and homocysteine are remarkably advantageous of the proposed DNA based biosensor.


Assuntos
Cisteína/análise , Eletrodos , Homocistina/análise , Nanopartículas/química , Níquel/química , Osmio/química , Técnicas Biossensoriais , Calibragem , Cisteína/sangue , Cisteína/química , DNA/química , Espectroscopia Dielétrica , Homocistina/química , Humanos , Limite de Detecção , Oxirredução , Sensibilidade e Especificidade
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