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1.
Anal Bioanal Chem ; 407(25): 7713-9, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26253229

RESUMO

A selenosugar (selenosugar 1, methyl-2-acetamido-2-deoxy-1-seleno-ß-D-galactopyranoside) was identified in aqueous extracts of muscle tissue of three marine fish species, mackerel (Scomber scombrus), sardine (Sardina pilchardus), and tuna (Thunnus albacares), by high-performance liquid chromatography coupled to elemental and high-resolution molecular mass spectrometry. Selenoneine (2-selenyl-Nα, Nα, Nα-trimethyl-L-histidine), a known selenium compound in fish, was the major form of selenium in the aqueous extracts, and the methylated derivative of selenoneine, namely Se-methylselenoneine, was also identified as a minor natural constituent in the fish. Selenosugar 1, a major urinary excretion product of selenium often found in organs and body fluids related to selenium excretion, has so far not been reported in muscle tissue. Se-methylselenoneine has been proposed as the main urinary metabolite from selenoneine. This first report of selenosugar 1 and Se-methylselenoneine as natural constituents of fish muscle tissue opens up a new perspective on the role of these compounds in selenium metabolism and is relevant to selenium supplementation studies.


Assuntos
Peixes/metabolismo , Galactose/metabolismo , Galactose/urina , Histidina/análogos & derivados , Compostos Organosselênicos/metabolismo , Compostos Organosselênicos/urina , Animais , Cromatografia Líquida de Alta Pressão/métodos , Galactose/análise , Histidina/análise , Histidina/metabolismo , Histidina/urina , Humanos , Músculos/metabolismo , Compostos Organosselênicos/análise
2.
Metallomics ; 3(5): 513-20, 2011 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-21331438

RESUMO

Speciation analysis of selenium in human urine allowed for the first time the identification of a novel selenium metabolite, Se-methylselenoneine. Despite a concentration at low ppb level, its characterization was achieved after sample purification by solid phase extraction (SPE) followed by the parallel coupling of the bidimensional RP/HILIC chromatography with ICP-MS and ESI-LTQ Orbitrap MS detection. To confirm its biological significance with regards to selenoneine, the recently discovered analog of ergothioneine, and to discard the possibility of sample preparation artifacts, a new method was developed to monitor its actual presence, as well as the occurrence of its sulfur and/or non-methylated analogs, in non-preconcentrated urine and blood samples of non-supplemented humans. It consisted in a HILIC ESI-MS(3) method in high resolution mode (resolution 30 000 at m/z 400) with large isolation width windows for precursor ions. These two particular settings allowed respectively to keep observing the specific mass defect of selenium- and sulfur-containing molecules and to maintain the characteristic selenium pattern in product ions created through MS(n) fragmentations. As a result, all four metabolites were detected in blood and three of them in urine. Moreover, different ratios "methylated/non-methylated" were observed between urine and blood samples, which seemed to indicate their active metabolization. The analytical tool developed here will be of a great importance to further study the occurrence and the potential metabolic role in mammalian organelles, cells and fluids of these very particular and promising redox metabolites.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Histidina/análogos & derivados , Compostos Organosselênicos/sangue , Compostos Organosselênicos/urina , Espectrometria de Massas por Ionização por Electrospray/métodos , Biomarcadores/sangue , Biomarcadores/urina , Histidina/sangue , Histidina/metabolismo , Histidina/urina , Humanos , Metilação , Compostos Organosselênicos/metabolismo , Reprodutibilidade dos Testes , Selênio/metabolismo , Enxofre/metabolismo
3.
Biol Trace Elem Res ; 101(3): 211-8, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15564651

RESUMO

Increased intake of chromium (Cr) often leads to improvements in glucose, insulin, lipids, and related variables in studies involving humans and experimental and farm animals. However, the results are often variable, depending not only on the selection of subjects but also dietary conditions and the form of supplemental Cr used. Our objective was to find a Cr supplement suitable for humans that was absorbed better than any of those available. Chromium absorption by six adult subjects, three males and three females, was determined based on the amount of Cr excreted in the urine in the initial 2 d following intake of 200 microg of Cr of the various forms of chromium tested. The absorption of the newly synthesized complexes was greatest for those containing histidine. Urinary Cr losses for six control subjects consuming 200 microg of Cr as Cr histidinate increased from basal levels of 256+/-48 to 3670+/-338 ng/d compared with 2082+/-201 ng for Cr picolinate, the currently most popular nutrient supplement, in the 48 h following Cr consumption. Chromium histidinate complexes were stable and absorption was similar to the initial values after more than 2 yr. Mixing of some of the complexes with starch, which was postulated to improve Cr absorption, was shown to essentially block Cr absorption within 1 mo. These data demonstrate that urinary Cr losses need to be determined because stability and absorption of the Cr complexes varies widely and could be responsible for the variability in some of the Cr supplementation studies. Chromium histidinate complexes are absorbed better than any of the Cr complexes currently available and need to be evaluated as Cr nutritional supplements.


Assuntos
Cromo/metabolismo , Cromo/farmacocinética , Histidina/análogos & derivados , Histidina/farmacocinética , Compostos Organometálicos/farmacocinética , Adulto , Cromo/urina , Dieta , Excipientes , Feminino , Histidina/metabolismo , Histidina/urina , Humanos , Absorção Intestinal , Modelos Lineares , Masculino , Compostos Organometálicos/metabolismo , Compostos Organometálicos/urina , Amido/metabolismo
4.
Clin Exp Pharmacol Physiol ; 31 Suppl 2: S2-4, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15649277

RESUMO

1. WHO-coordinated Cardiovascular Diseases and Alimentary Comparison Study (CARDIAC) and its follow-up, MONALISA Study covering 60 populations in 25 countries indicated an increasing prevalence of obesity, even in developing countries. 2. The index of obesity, BMI was confirmed to be related positively with both systolic and diastolic blood pressure (BP) in 60 CARDIAC populations and with the age-adjusted mortality rates of coronary heart diseases (CHD) in 25 populations where reliable demographic data were available. 3. CHD mortality rates were inversely related with biomarkers for soy bean and fish intakes, isoflavones and taurine in 24-h urine samples in 25 CARDIAC study populations. 4. Population samples were divided into two groups: soy eaters and non-eaters as well as fish eaters and non-eaters, respectively, based on WHO-CARDIAC study data. Soy eaters as well as fish eaters had significantly lower BMI, BP and serum cholesterol levels, which are three major CHD risk factors. 5. BMI was inversely related with 24-h urinary isoflavones excretion, the biomarker of soy intake and also with 24-h urinary excretion of histidine, relatively rich in fish. 6. Since both nutrients, isoflavones as phytoestrogen and histidine as the precursor of histamine may affect central appetite mechanisms, soy and fish intake may be recommended to control obesity, the major common risk of lifestyle-related diseases.


Assuntos
Dieta , Peixes , Glycine max , Obesidade/epidemiologia , Animais , Povo Asiático , Pressão Sanguínea , Índice de Massa Corporal , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/urina , Colesterol/sangue , Surtos de Doenças , Ácidos Graxos Ômega-3/sangue , Feminino , Histidina/urina , Humanos , Hipercolesterolemia/epidemiologia , Hipercolesterolemia/urina , Hipertensão/epidemiologia , Hipertensão/urina , Isoflavonas/urina , Masculino , Pessoa de Meia-Idade , Obesidade/urina , Taurina/urina
5.
J Nutr ; 114(2): 369-84, 1984 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-6693997

RESUMO

The purpose of this 85-day study was to investigate the long-term effects of histidine depletion on nitrogen utilization in young adult men. A low nitrogen (6.3 g/day), low histidine (10 mg/day) amino acid diet was fed to seven men for 8 weeks. Mean nitrogen balance became negative at the end of the 8-week period. Free histidine in postabsorptive plasma and 24-hour urine decreased significantly during the first 2 weeks of the depletion and remained low and constant for the remaining 6 weeks. Hemoglobin concentration decreased somewhat, and serum iron concentration increased significantly during histidine depletion. Lean body mass, urinary N'-methylhistidine and total creatinine did not change significantly. On addition of histidine to the low histidine diet for 2 weeks, nitrogen retention became positive, plasma and urinary histidine returned to initial values, serum iron fell, and hemoglobin concentration slowly increased. These parameters remained unchanged in two control men fed the same diet supplemented with histidine (1.05 g/day) for 8 weeks. The results suggest that histidine is indispensable for young men consuming a low nitrogen diet.


Assuntos
Histidina/deficiência , Nitrogênio/metabolismo , Adulto , Proteínas Sanguíneas/metabolismo , Nitrogênio da Ureia Sanguínea , Creatinina/urina , Dieta , Índices de Eritrócitos , Histidina/sangue , Histidina/urina , Humanos , Ferro/sangue , Estudos Longitudinais , Masculino , Músculos/metabolismo
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