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1.
Clin Nutr ; 40(7): 4624-4632, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34229268

RESUMEN

BACKGROUND AND AIMS: Vitamin B6 is involved in a large spectrum of physiological processes and comprises of the vitamers pyridoxamine (PM), pyridoxal (PL), pyridoxine (PN), and their phosphorylated derivatives including the biological active pyridoxal 5'-phosphate (PLP). While PN toxicity is known to complicate several treatments, PM has shown promise in relation to the treatment of metabolic and age-related diseases by blocking oxidative degradation and scavenging toxic dicarbonyl compounds and reactive oxygen species. We aimed to assess the metabolization of oral PM supplements in a single and three daily dose. MATERIALS AND METHODS: We optimized and validated a method for the quantification of the B6 vitamers in plasma and urine using ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). Five healthy volunteers were recruited to study PM metabolization after a single oral dose of 200 mg PM or a three daily dose of 67 mg PM. A third protocol was implemented as control for dietary intake. Venous blood samples, 24 h urine and fasted second void urine samples were collected. RESULTS: After a single oral dose of 200 mg PM, plasma PM increased in the first 3 h to a maximum of 2324 ± 266 nmol/L. While plasma PM levels returned to baseline after ~10 h of PM intake, PLP increased to a maximum of 2787 ± 329 nmol/L and reached a plateau. We found a small increase of PN to a maximum of 13.5 ± 2.1 nmol/L; it was nearly undetectable after ~12 h. With a three daily dose of 67 mg PM we observed an increase and decline of plasma PM, PL, and PN concentrations after each PM intake. PLP showed a similar increase as in the single dose protocol and accumulated over time. CONCLUSION: In this study we showed high plasma levels of PM after oral PM supplementation. We found steadily increasing levels of the biologically active PLP, with minimal formation of PN. The B6 vitamer PM is an interesting supplement as an inhibitor of harmful processes in metabolic diseases and for the treatment of vitamin B6 deficiency. CLINICAL TRIAL REGISTRY: The study was approved by the Medical Ethics Committee of Maastricht University (NL) and was registered at ClinicalTrials.gov as NCT02954588.


Asunto(s)
Suplementos Dietéticos , Piridoxamina/administración & dosificación , Vitamina B 6/sangre , Vitamina B 6/orina , Adulto , Cromatografía Líquida de Alta Presión , Femenino , Voluntarios Sanos , Humanos , Masculino , Fosfato de Piridoxal/sangre , Fosfato de Piridoxal/orina , Piridoxamina/sangre , Piridoxamina/orina , Piridoxina/sangre , Piridoxina/orina , Espectrometría de Masas en Tándem , Deficiencia de Vitamina B 6/terapia
2.
J Nutr Biochem ; 70: 38-46, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31151052

RESUMEN

Autism spectrum disorder (ASD) is characterized by severe and persistent difficulties in social communication and social interaction at multiple levels. Recently, metabolic disorders have been associated with most cases of patients with ASD. The aim of this study was to investigate, through a new and more sophisticated mass technique, such as UHPLC-mass spectrometry (Q-exactive analyzer), alteration in metabolisms analyzing ASD children urine samples from children showing simultaneous vitamin B6, B9 and B12 deficiencies. This in order to study how these concurrent deficiencies may influence some phenotypic aspects of autistic disorder. Thus, urinary metabolic patterns specific to ASD were explored at an early age in 60 children with ASD, showing lower three vitamins levels, and 60 corresponding controls (age group 3-8, M: F=42:18). The results showed significant block of cystathionine formation with consequent accumulation of homocysteine. A lower glutathione levels (GSH), with reduction of essential intracellular reducing environment required for normal immune function, detoxification capacity and redox-sensitive enzyme activity. Increased concentration of 5-methyltetrahydrofolate, which leads to a lower availability of methyl group and significant decrease in urinary methionine and S-adenosyl-L-methionine (SAM) concentrations, the major methyl donor. The latter justify the well-known reduction in protein and DNA methylation reported in autistic children. As a final consideration, the concomitant deficiencies of all three B vitamins, recorded in a significant number of autistic children, suggests that intestinal dysbiosis in these patients may be the main cause of a reduction in their absorption, in addition to the genetic mutation of a specific gene.


Asunto(s)
Trastorno del Espectro Autista/orina , Ácido Fólico/orina , Metilación , Vitamina B 12/orina , Vitamina B 6/orina , 5-Metiltetrahidrofolato-Homocisteína S-Metiltransferasa/metabolismo , Niño , Preescolar , Cromatografía Líquida de Alta Presión , Cistationina/metabolismo , Femenino , Glutatión/metabolismo , Homocisteína/sangre , Humanos , Masculino , Espectrometría de Masas , Metionina/orina , Mutación , Oxidación-Reducción , Fenotipo
3.
Mol Autism ; 7: 47, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27904735

RESUMEN

BACKGROUND: Autism spectrum disorder (ASD) is still diagnosed through behavioral observation, due to a lack of laboratory biomarkers, which could greatly aid clinicians in providing earlier and more reliable diagnoses. Metabolomics on human biofluids provides a sensitive tool to identify metabolite profiles potentially usable as biomarkers for ASD. Initial metabolomic studies, analyzing urines and plasma of ASD and control individuals, suggested that autistic patients may share some metabolic abnormalities, despite several inconsistencies stemming from differences in technology, ethnicity, age range, and definition of "control" status. METHODS: ASD-specific urinary metabolomic patterns were explored at an early age in 30 ASD children and 30 matched controls (age range 2-7, M:F = 22:8) using hydrophilic interaction chromatography (HILIC)-UHPLC and mass spectrometry, a highly sensitive, accurate, and unbiased approach. Metabolites were then subjected to multivariate statistical analysis and grouped by metabolic pathway. RESULTS: Urinary metabolites displaying the largest differences between young ASD and control children belonged to the tryptophan and purine metabolic pathways. Also, vitamin B6, riboflavin, phenylalanine-tyrosine-tryptophan biosynthesis, pantothenate and CoA, and pyrimidine metabolism differed significantly. ASD children preferentially transform tryptophan into xanthurenic acid and quinolinic acid (two catabolites of the kynurenine pathway), at the expense of kynurenic acid and especially of melatonin. Also, the gut microbiome contributes to altered tryptophan metabolism, yielding increased levels of indolyl 3-acetic acid and indolyl lactate. CONCLUSIONS: The metabolic pathways most distinctive of young Italian autistic children largely overlap with those found in rodent models of ASD following maternal immune activation or genetic manipulations. These results are consistent with the proposal of a purine-driven cell danger response, accompanied by overproduction of epileptogenic and excitotoxic quinolinic acid, large reductions in melatonin synthesis, and gut dysbiosis. These metabolic abnormalities could underlie several comorbidities frequently associated to ASD, such as seizures, sleep disorders, and gastrointestinal symptoms, and could contribute to autism severity. Their diagnostic sensitivity, disease-specificity, and interethnic variability will merit further investigation.


Asunto(s)
Trastorno del Espectro Autista/orina , Disbiosis/orina , Metabolómica/métodos , Purinas/orina , Triptófano/orina , Trastorno del Espectro Autista/complicaciones , Trastorno del Espectro Autista/diagnóstico , Biomarcadores/orina , Estudios de Casos y Controles , Niño , Preescolar , Cromatografía Líquida de Alta Presión , Coenzima A/orina , Disbiosis/complicaciones , Disbiosis/diagnóstico , Femenino , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Ácidos Indolacéticos/orina , Italia , Ácido Quinurénico/orina , Masculino , Melatonina/orina , Ácido Pantoténico/orina , Pirimidinas/orina , Ácido Quinolínico/orina , Riboflavina/orina , Vitamina B 6/orina , Xanturenatos/orina
4.
Biosci Biotechnol Biochem ; 80(2): 304-12, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26745680

RESUMEN

B-group vitamins are involved in the catabolism of 2-oxo acids. To identify the functional biomarkers of B-group vitamins, we developed a high-performance liquid chromatographic method for profiling 2-oxo acids in urine and applied this method to urine samples from rats deficient in vitamins B1 and B6 and pantothenic acid. 2-Oxo acids were reacted with 1,2-diamino-4,5-methylenebenzene to produce fluorescent derivatives, which were then separated using a TSKgel ODS-80Ts column with 30 mmol/L of KH2PO4 (pH 3.0):acetonitrile (7:3) at a flow rate of 1.0 mL/min. Vitamin B1 deficiency increased urinary levels of all 2-oxo acids, while vitamin B6 deficiency only increased levels of sum of 2-oxaloacetic acid and pyruvic acid, and pantothenic acid deficiency only increased levels of 2-oxoisovaleric acid. Profiles of 2-oxo acids in urine samples might be a non-invasive way of clarifying the functional biomarker of B-group vitamins.


Asunto(s)
Cromatografía Líquida de Alta Presión/normas , Ácido Pantoténico/orina , Deficiencia de Tiamina/orina , Tiamina/orina , Deficiencia de Vitamina B 6/orina , Vitamina B 6/orina , Adipatos/orina , Animales , Biomarcadores/orina , Hemiterpenos , Cetoácidos/orina , Ácidos Cetoglutáricos/orina , Masculino , Ácido Oxaloacético/orina , Ácido Pantoténico/deficiencia , Fenilendiaminas/química , Ácido Pirúvico/orina , Ratas , Ratas Wistar , Espectrometría de Fluorescencia
5.
J Nutr Sci Vitaminol (Tokyo) ; 61(5): 355-61, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26639842

RESUMEN

Fatty liver is caused when rats are given orotic acid of the pyrimidine base in large quantities. The lack of B-group vitamins suppresses the biosynthesis of fatty acids. We investigated how orotic acid-induced fatty liver affects the concentrations of liver, blood, and urine B-group vitamins in rats. The vitamin B6 and B12 concentrations of liver, blood, and urine were not affected by orotic acid-induced fatty liver. Vitamin B2 was measured only in the urine, but was unchanged. The liver, blood, and urine concentrations of niacin and its metabolites fell dramatically. Niacin and its metabolites in the liver, blood, and urine were affected as expected. Although the concentrations of vitamin B1, pantothenic acid, folate, and biotin in liver and blood were decreased by orotic acid-induced fatty liver, these urinary excretion amounts showed a specific pattern toward increase. Generally, as for the typical urinary excretion of B-group vitamins, these are excreted when the body is saturated. However, the ability to sustain vitamin B1, pantothenic acid, folate, and biotin decreased in fatty liver, which is hypothesized as a specific phenomenon. This metabolic response might occur to prevent an abnormally increased biosynthesis of fatty acids by orotic acid.


Asunto(s)
Hígado Graso/sangre , Hígado Graso/orina , Hígado/efectos de los fármacos , Ácido Orótico/efectos adversos , Complejo Vitamínico B/sangre , Complejo Vitamínico B/orina , Animales , Biotina/sangre , Biotina/orina , Hígado Graso/inducido químicamente , Ácido Fólico/sangre , Ácido Fólico/orina , Hígado/metabolismo , Masculino , Niacina/sangre , Niacina/orina , Ácido Pantoténico/sangre , Ácido Pantoténico/orina , Ratas , Ratas Wistar , Riboflavina/sangre , Riboflavina/orina , Tiamina/sangre , Tiamina/orina , Vitamina B 6/sangre , Vitamina B 6/orina , Aumento de Peso
6.
Annu Rev Nutr ; 35: 33-70, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25974692

RESUMEN

Measures of B6 status are categorized as direct biomarkers and as functional biomarkers. Direct biomarkers measure B6 vitamers in plasma/serum, urine and erythrocytes, and among these plasma pyridoxal 5'-phosphate (PLP) is most commonly used. Functional biomarkers include erythrocyte transaminase activities and, more recently, plasma levels of metabolites involved in PLP-dependent reactions, such as the kynurenine pathway, one-carbon metabolism, transsulfuration (cystathionine), and glycine decarboxylation (serine and glycine). Vitamin B6 status is best assessed by using a combination of biomarkers because of the influence of potential confounders, such as inflammation, alkaline phosphatase activity, low serum albumin, renal function, and inorganic phosphate. Ratios between substrate-products pairs have recently been investigated as a strategy to attenuate such influence. These efforts have provided promising new markers such as the PAr index, the 3-hydroxykynurenine:xanthurenic acid ratio, and the oxoglutarate:glutamate ratio. Targeted metabolic profiling or untargeted metabolomics based on mass spectrometry allow the simultaneous quantification of a large number of metabolites, which are currently evaluated as functional biomarkers, using data reduction statistics.


Asunto(s)
Biomarcadores/sangre , Estado Nutricional , Deficiencia de Vitamina B 6/sangre , Vitamina B 6 , Aminoácidos/sangre , Biomarcadores/orina , Índice de Masa Corporal , Femenino , Estado de Salud , Humanos , Lactante , Recién Nacido , Inflamación , Quinurenina/sangre , Estilo de Vida , Masculino , Metaboloma , Metabolómica , Embarazo , Piridoxal/sangre , Fosfato de Piridoxal/sangre , Ácido Piridóxico/orina , Transaminasas , Vitamina B 6/sangre , Vitamina B 6/fisiología , Vitamina B 6/orina , Deficiencia de Vitamina B 6/orina
7.
Vopr Pitan ; 84(3): 70-6, 2015.
Artículo en Ruso | MEDLINE | ID: mdl-26863809

RESUMEN

Vitamin status and bone strength have been estimated in 91 pregnant women (29.3 ± 4.6 years old) from Moscow by non-invasive methods. Sufficiency with vitamins C, B2, B6 has been evaluated by morning urinary excretion of ascorbic acid, riboflavin and 4-piridoxic acid determined by visual titration and fluorimetric methods. The rate of bone resorption has been measured by the ratio of urinary calcium and creatinine, determined by complexometric titration and spectrophotometrically. The study of the bone strength has been conducted using an ultrasonic densitometer (the speed of the ultrasonic waves along the cortical layer). The lack of vitamin C was found in 20.4% .of the women surveyed, vitamin B2--in 27.4%. Vitamin B6 deficiency was detected most frequently (90%). Excretion of vitamins B2 and B6 in women in the third trimester of pregnancy was lower as compared with the women in the first and second trimester. In 53.3% of the women surveyed an increase in urinary excretion of calcium per creatinine has been observed. Excretion of group B vitamins (especially vitamin B6, 1.75 fold, p < 0.05) in women taking vitamin supplements was higher compared to non-taking vitamins that indicates the better sufficiency of the organism with these vitamins. Among women who took vitamin complexes, inadequate supply with water-soluble vitamins C, B2 and B6 was detected less frequently (the difference was significant for vitamin B2) than among women who did not intake vitamin complexes (in 11.9, 27.7 and 42.4% vs 16.1, 54.8 and 48.8 %). The rate of bone resorption (Ca/creatinine) in women taking vitamins was smaller (0.19 ± 0.09 vs 0.24 ± 0.14, p > 0.05). Ca/creatinine ratio was within normal range in 40% of women who intake vitamins, while in women not taking vitamins--only in 22.2%; this value exceeded the upper limit of norm in the rest. The strength of bone was broken in women in the second and third trimester of pregnancy, having worse supply of vitamins. The percentage of agreement of the results of osteopenia diagnosis assessment (ultrasound densitometry and urinary Ca/creatinine) was 42.2%. Thus, the conclusion has been confirmed that the evaluation of the status of bone is possible only basing on the results of determination of several parameters.


Asunto(s)
Ácido Ascórbico/orina , Densidad Ósea/fisiología , Embarazo/orina , Riboflavina/orina , Vitamina B 6/orina , Adulto , Femenino , Humanos
8.
PLoS One ; 8(2): e56194, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23457526

RESUMEN

BACKGROUND: Folate status, as reflected by red blood cell (RCF) and plasma folates (PF), is related to health and disease risk. Folate degradation products para-aminobenzoylglutamate (pABG) and para-acetamidobenzoylglutamate (apABG) in 24 hour urine have recently been shown to correlate with blood folate. AIM: Since blood sampling and collection of 24 hour urine are cumbersome, we investigated whether the determination of urinary folate catabolites in fasted spot urine is a suitable non-invasive biomarker for folate status in subjects before and during folic acid supplementation. STUDY DESIGN AND METHODS: Immediate effects of oral folic acid bolus intake on urinary folate catabolites were assessed in a short-term pre-study. In the main study we included 53 healthy men. Of these, 29 were selected for a 12 week folic acid supplementation (400 µg). Blood, 24 hour and spot urine were collected at baseline and after 6 and 12 weeks and PF, RCF, urinary apABG and pABG were determined. RESULTS: Intake of a 400 µg folic acid bolus resulted in immediate increase of urinary catabolites. In the main study pABG and apABG concentrations in spot urine correlated well with their excretion in 24 hour urine. In healthy men consuming habitual diet, pABG showed closer correlation with PF (rs = 0.676) and RCF (rs = 0.649) than apABG (rs = 0.264, ns and 0.543). Supplementation led to significantly increased folate in plasma and red cells as well as elevated urinary folate catabolites, while only pABG correlated significantly with PF (rs = 0.574) after 12 weeks. CONCLUSION: Quantification of folate catabolites in fasted spot urine seems suitable as a non-invasive alternative to blood or 24 hour urine analysis for evaluation of folate status in populations consuming habitual diet. In non-steady-state conditions (folic acid supplementation) correlations between folate marker (RCF, PF, urinary catabolites) decrease due to differing kinetics.


Asunto(s)
Suplementos Dietéticos , Ácido Fólico/metabolismo , Ácido Fólico/orina , Adulto , Suplementos Dietéticos/análisis , Ácido Fólico/administración & dosificación , Ácido Fólico/sangre , Glutamatos/sangre , Glutamatos/metabolismo , Glutamatos/orina , Homocisteína/sangre , Homocisteína/orina , Humanos , Masculino , Urinálisis , Vitamina B 12/sangre , Vitamina B 12/orina , Vitamina B 6/sangre , Vitamina B 6/orina , Adulto Joven
9.
Appl Physiol Nutr Metab ; 37(1): 167-75, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22288928

RESUMEN

Vitamin B(6) (pyridoxine) metabolism in diabetes has never been investigated except for a few reports on plasma pyridoxal 5'-phosphate (PLP). These studies indicated that this most active (coenzyme) vitamer can be reduced. The present clinical investigation aimed to measure all vitamers in blood and urine by high performance liquid chromatography as well as important related factors, in women during active reproductive years. Thirty-two insulin-treated type 1 diabetic (T1D) patients, without renal complication, and 27 well-matched healthy controls, aged 30 to 40 years old, were recruited using rigorous criteria. Both groups had normal hemoglobin and serum albumin levels. Plasma PLP and pyridoxal (PL) did not differ significantly in the T1D group but alkaline phosphatase (ALP) activity was greater (p < 0.01). This produced a shift in plasma PLP-PL profile, as evidenced by a lower plasma PLP/PL ratio (p < 0.05). Enhanced ALP activity meant more PLP being dephosphorylated to PL (the membrane transfer form), with more ending up in erythrocytes to be rephosphorylated in its active form, as suggested by the significant positive correlation (p < 0.001) between plasma PL and erythrocyte PLP. More PL into blood circulation also means more oxidation of this vitamer to 4'-pyridoxic acid in kidneys, as confirmed by the positive correlation between plasma PL and urinary 4'-pyridoxic acid (p < 0.001). The positive correlation (p < 0.001) between ALP activity and glycosylated hemoglobin indicated a direct effect of the disease. The T1D-induced alteration in vitamin B(6) metabolism, consecutive to enhanced ALP activity, may put patients at greater risk of vitamin B(6) deficiency and diabetic complications.


Asunto(s)
Diabetes Mellitus Tipo 1/sangre , Diabetes Mellitus Tipo 1/orina , Vitamina B 6/sangre , Vitamina B 6/orina , Adulto , Factores de Edad , Fosfatasa Alcalina/sangre , Biomarcadores/sangre , Biomarcadores/orina , Estudios de Casos y Controles , Distribución de Chi-Cuadrado , Cromatografía Líquida de Alta Presión , Complicaciones de la Diabetes/sangre , Complicaciones de la Diabetes/etiología , Complicaciones de la Diabetes/orina , Diabetes Mellitus Tipo 1/complicaciones , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Femenino , Hemoglobina Glucada/análisis , Humanos , Hipoglucemiantes/uso terapéutico , Insulina/uso terapéutico , Nuevo Brunswick , Fosfato de Piridoxal/sangre , Fosfato de Piridoxal/orina , Reproducción , Medición de Riesgo , Factores de Riesgo , Factores Sexuales , Deficiencia de Vitamina B 6/sangre , Deficiencia de Vitamina B 6/etiología , Deficiencia de Vitamina B 6/orina
10.
Hepatogastroenterology ; 58(105): 31-5, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21510282

RESUMEN

BACKGROUND/AIMS: Appropriateness of the vitamin doses in Japanese commercial multi-vitamin preparations for parenteral nutrition therapy was investigated in patients with gastrointestinal tract disorder by evaluating the vitamin status (blood concentrations and urinary excretions of vitamins B1, B2, B6, and C) of them. METHODOLOGY: Commercial multivitamin preparations were administered continuously with a commercial PN solution over 5 days to 10 patients with gastrointestinal tract disorder. Blood concentrations of vitamins B1, B2, B6, and C were measured on the mornings of day 1, day 4, and day 6. Urinary excretions were measured in 24-h urine collections collected after day 3 and after day 5. RESULTS: Blood concentrations of vitamins B1, B2, and B6 increased but remained within or slightly above the normal throughout the study, and urinary excretion values were normal in all patients. However, blood vitamin C concentration surpassed the lower limit of normal (5.5 microg/mL) only on day 6. Urinary vitamin C excretion was below normal (20.0 mg/day) in all and 7 patients on days 3 and 5, respectively. CONCLUSIONS: In patients with gastrointestinal tract disorder, the doses of vitamins B1, B2, and B6 of Japanese commercial multi-vitamin preparations are adequate but that of vitamin C (100 mg/day) is inadequate and should be increased.


Asunto(s)
Ácido Ascórbico/administración & dosificación , Enfermedades Gastrointestinales/terapia , Nutrición Parenteral , Ácido Ascórbico/sangre , Ácido Ascórbico/orina , Femenino , Humanos , Japón , Masculino , Persona de Mediana Edad , Riboflavina/administración & dosificación , Riboflavina/sangre , Riboflavina/orina , Tiamina/administración & dosificación , Tiamina/sangre , Tiamina/orina , Vitamina B 6/administración & dosificación , Vitamina B 6/sangre , Vitamina B 6/orina
11.
J Ren Nutr ; 20(5 Suppl): S95-102, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20797580

RESUMEN

OBJECTIVE: Vitamin B(6) (VB(6)) is a water-soluble vitamin, which is important for the normal functioning of multiple organ systems. It is metabolized to the active molecule pyridoxal-5-phosphate (PLP). Oxalic acid (OA) is thought to be a uremic toxin that participates in the pathogenesis of the uremic syndrome. The objectives of this study were as follows: (1) to evaluate the plasma and erythrocyte VB(6) (effect of PLP; effect of PLP was in indirect relationship with the concentration of erythrocyte VB(6)), and plasma and urinary OA in marathon runners, in patients with acute intermittent porphyria (AIP) and variegate porphyria, and in patients with stage 1 chronic kidney disease (CKD), chronic glomerulonephritis and nephrotic syndrome (CGNS); (2) to examine the influence of water diuresis in healthy subjects, and the influence of sodium diuresis (high sodium intake) and an intravenous administration of furosemide on the urinary excretion of VB(6) and OA in CKD stage 3-4 patients; and (3) to evaluate the influence of erythropoietin treatment on erythrocyte VB(6) (effect of PLP) in hemodialysis (HD) patients, and the influence of continuous ambulatory peritoneal dialysis (CAPD) therapy on plasma VB(6) and OA and their peritoneal clearance and transfer. DESIGN AND SETTING: This study was conducted at the Nephrological Clinic of L. Pasteur Faculty Hospital and of Medical School of P. J. Safarik University. A combination of 29 marathon runners, 15 patients with CG and NS, 11 patients with AIP, 1 patient with variegate porphyria, 15 healthy subjects, 27 CKD stage 3-4 patients, 30 HD, and 27 CAPD patients were used in the study. RESULTS: After a marathon run, plasma and erythrocyte VB(6) significantly decreased and plasma OA increased. Plasma (15.5 +/- 3.8 nmol/L) and erythrocyte VB(6) (effect of PLP: 42.1% +/- 7.5%) were decreased and plasma OA (9.8 +/- 2.3 micromol/L) was significantly elevated in patients with CGNS and stage 1 CKD. In patients with AIP, deficiency of plasma (24.3 +/- 5.2 nmol/L) and erythrocyte VB(6) (effect of PLP: 46.2% +/- 7.0%) and hyperoxalemia (9.39 +/- 2.5 micromol/L) were present. The urinary excretion of VB(6) and of OA during maximal water diuresis and after intravenous administration of furosemide increased significantly (P < .01), but was not affected by the high intake of NaCl (P > .05). Erythropoietin treatment in HD patients led to the erythrocyte VB(6) deficiency. This finding is an indirect evidence that erythrocyte VB(6) is consumed by the hemoglobin synthesis much more during EPO treatment. In CAPD patients, plasma value of VB(6) (127.3 +/- 66.9 micromol/L) was in the normal range and plasma OA (23.6 +/- 7.4 micromol/L) was significantly elevated. Mean value of peritoneal clearance of VB(6) was 8.8% and of OA was 76.9% of urea clearance. CONCLUSION: Our study indicates that deficiency of VB(6) led to hyperoxalemia and hyperoxaluria in patients with CKD. Deficiency of VB(6) in CKD stage 4-5 patients potentiates the uremic hyperoxalemia and hyperoxaluria.


Asunto(s)
Enfermedades Renales/metabolismo , Ácido Oxálico/análisis , Vitamina B 6/análisis , Adulto , Soluciones para Diálisis/análisis , Eritrocitos/química , Femenino , Glomerulonefritis/sangre , Glomerulonefritis/metabolismo , Glomerulonefritis/orina , Humanos , Enfermedades Renales/sangre , Enfermedades Renales/orina , Masculino , Síndrome Nefrótico/sangre , Síndrome Nefrótico/metabolismo , Síndrome Nefrótico/orina , Ácido Oxálico/sangre , Ácido Oxálico/orina , Diálisis Peritoneal Ambulatoria Continua , Porfiria Intermitente Aguda/sangre , Porfiria Intermitente Aguda/metabolismo , Porfiria Intermitente Aguda/orina , Diálisis Renal , Carrera/fisiología , Vitamina B 6/sangre , Vitamina B 6/orina
12.
J Nutr Sci Vitaminol (Tokyo) ; 56(3): 157-63, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20651455

RESUMEN

A method for determining all of the six natural vitamin B(6) compounds and pyridoxine-beta-glucoside in urine from humans consuming their usual diet was developed. These compounds were specifically converted with 5 enzymes into a high fluorescent 4-pyridoxolactone which was supersensitively determined by an isocratic HPLC. All of the compounds in urine from humans consuming their usual diets were for the first time determined together. The preparation procedure for urine samples was easy without HCl-hydrolysis, and the enzyme reactions took only 2 or 3 h. It required only 5 microL of the urine sample for analysis of one of the compounds. Urine samples from five young Japanese males consuming their usual diet contained pyridoxal, pyridoxamine, and pyridoxine-beta-glucoside but not pyridoxine or phosphoester forms. The contents of 4-pyridoxic acid and pyridoxal correlate well with a correlation coefficient of 0.98. On the other hand, the content of pyridoxamine did not correlate with that of 4-pyridoxic acid.


Asunto(s)
Glucósidos/orina , Piridoxina/análogos & derivados , Vitamina B 6/orina , Adulto , Métodos Analíticos de la Preparación de la Muestra , Cromatografía Líquida de Alta Presión , Glucósidos/metabolismo , Humanos , Masculino , Microquímica/métodos , Piridoxal/análogos & derivados , Piridoxal/química , Piridoxal/metabolismo , Piridoxal/orina , Piridoxamina/metabolismo , Piridoxamina/orina , Ácido Piridóxico/metabolismo , Ácido Piridóxico/orina , Piridoxina/metabolismo , Piridoxina/orina , Factores de Tiempo , Vitamina B 6/metabolismo , Adulto Joven
13.
Nutr Res ; 30(3): 171-8, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20417877

RESUMEN

We hypothesized that 24-hour urinary excretion of water-soluble vitamins might correlate with their intake in free-living Japanese elderly females aged 70 to 84 years. We performed a cross-sectional study composed of 37 healthy, elderly, Japanese females living freely. All foods and the corresponding weights consumed for 4 consecutive days were recorded accurately. A 24-hour urine sample was collected on the fourth day, and the urinary content of water-soluble vitamins was measured. The urinary levels of all vitamins, except for B(12) (r = 0.01; P = .936), were correlated positively with the mean intake over the recent 4 days (vitamin B1: r = 0.62; P < .001; vitamin B2: r = 0.57; P < .001; vitamin B6: r = 0.37; P < .005; niacin: r = 0.54; P < .001; niacin equivalents: r = 0.54; P < .001; pantothenic acid: r = 0.59; P < .001; folate: r = 0.55; P = .001; and vitamin C: r = 0.53; P < .001). Mean estimated intakes of water-soluble vitamins calculated using urinary concentrations and recovery rates showed 96% to 107% of their 3-day mean intake, except for vitamin B12 (65%). We conclude that urinary levels of water-soluble vitamins, except for B12, reflected their recent intake in free-living Japanese elderly females and could be used as a measure of their intake during the previous few days both for group means and for individual rankings within a group.


Asunto(s)
Ácido Ascórbico/administración & dosificación , Ácido Ascórbico/orina , Dieta , Complejo Vitamínico B/administración & dosificación , Complejo Vitamínico B/orina , Anciano , Anciano de 80 o más Años , Estudios Transversales , Femenino , Ácido Fólico/administración & dosificación , Ácido Fólico/orina , Humanos , Japón , Niacina/administración & dosificación , Niacina/orina , Ácido Pantoténico/administración & dosificación , Ácido Pantoténico/orina , Riboflavina/administración & dosificación , Riboflavina/orina , Tiamina/administración & dosificación , Tiamina/orina , Vitamina B 12/administración & dosificación , Vitamina B 12/orina , Vitamina B 6/administración & dosificación , Vitamina B 6/orina
14.
Acta bioquím. clín. latinoam ; 41(1): 67-76, ene.-mar. 2007. graf, tab
Artículo en Español | LILACS | ID: lil-632996

RESUMEN

Estudios previos en ratas han demostrado que la administración del diurético furosemida aumenta la pérdida urinaria de electrolitos y nutrientes, causando un efecto negativo sobre las reservas de los mismos. Una alternativa para proteger esas reservas es incrementar la absorción intestinal. Así, se evaluó la absorción, pérdidas urinarias y reservas corporales de nitrógeno, calcio, magnesio, sodio, potasio y cinc, en cuatro grupos de ratas: control, y tres grupos experimentales que consumieron furosemida en concentraciones de 0,5; 1,0 y 1,5 mg/g de dieta, durante 23 días. El diurético causó poliuria dosis dependiente, disminución en el consumo de alimento, la eficiencia y el crecimiento. También, provocó un aumento en las pérdidas urinarias del nitrógeno y minerales. La absorción de nitrógeno, calcio y cinc no se modificó, mientras que la del magnesio, sodio y potasio aumentó ligeramente. Se determinó que la absorción no compensó las pérdidas urinarias. Así, la furosemida afectó negativamente la retención de nutrientes y electrolitos, provocando una reducción en las reservas corporales de los mismos. Este diurético tiene un efecto negativo sobre el estado nutricional en ratas, causado por la reducción en el consumo de alimento, así como en la utilización de los nutrientes consumidos. La reducción en la utilización de los nutrientes asociada con este diurético, puede ser explicada en parte, por una pobre retención de nutrientes por el riñón, que no puede ser compensada por un incremento en la absorción intestinal.


Previous studies have shown that, in rats, the administration of the diuretic furosemide increases diuresis as well as urinary loss of electrolytes and essential nutrients. This loss has a negative effect on electrolytes and nutrient reserves. Since one alternative to help protect these reserves is to increase intestinal absorption, the purpose of this study was to evaluate the absorption, urinary loss and tissue reserves of nitrogen, calcium, magnesium, sodium, potassium and zinc in rats offered 0, 0.5, 1.0 and 1.5 mg furosemide per g diet, daily during 23 days. The diuretic caused a dose dependent polyuria, a reduction in food intake, growth and feed efficiency. In addition, those rats had increased urinary loss of nitrogen and minerals. Nitrogen, calcium and zinc absorption were not affected, but magnesium, sodium and potassium increased slightly. Intestinal absorption could not compensate for urinary loss. In general, this study showed that in rats, this diuretic had a negative effect on nutritional status caused by a reduction in food intake and also in the utilization of the nutrients consumed. The reduction in nutrient utilization associated with this diuretic may be partly explained by a poor nutrient retention by the kidney which was not compensated by an increase in intestinal absorption.


Asunto(s)
Animales , Ratas , Diuresis/efectos de los fármacos , Furosemida/farmacocinética , Ácido Ascórbico/orina , Tiamina/orina , Bicarbonatos/farmacocinética , Alimentos , Calcio/orina , Calcio/farmacocinética , Ratas Sprague-Dawley , Vitamina B 6/orina , Dietoterapia/veterinaria , Furosemida/administración & dosificación , Furosemida/antagonistas & inhibidores , Furosemida/efectos adversos , Furosemida/metabolismo , Furosemida/orina
15.
J Nutr Sci Vitaminol (Tokyo) ; 51(6): 385-91, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16521696

RESUMEN

To acquire the data concerning the tolerable upper intake level which prevents health problems from an excessive intake of pantothenic acid, an animal experiment was done. Rats of the Wistar strain (male, 3 wk old) were fed on a diet which contains 0%, 0.0016% (control group), 1%, or 3% calcium pantothenate for 29 d. The amount of weight increase, the food intake, and the organ weights were measured, as well as the pantothenic acid contents in urine, the liver and blood. Moreover, to learn the influence of excessive pantothenic acid on other water-soluble vitamin metabolism, thiamin, riboflavin, a vitamin B6 catabolite, the niacin catabolites, and ascorbic acid in urine were measured. As for the 3% addition group, enlargement of the testis, diarrhea, and hair damage were observed, and the amount of weight increase and the food intake were less than those of the control group. However, abnormality was not seen in the 1% addition group. The amount of pantothenic acid in urine, the liver, and blood showed a high correlation with intake level of pantothenic acid. It was only for 4-pyridoxic acid, a vitamin B6 catabolite, in urine that a remarkable difference was observed against the control group. Moreover, the (2-Py+4-Py)/MNA excretion ratio for these metabolites of the nicotinamide also indicated a low value in the 3% pantothenic acid group. As for the calcium pantothenate, it was found that the 3% level in the diet was the lowest-observed-adverse-effect-level (LOAEL) and the 1% level was the no-observed-adverse-effect-level (NOAEL).


Asunto(s)
Ácido Pantoténico/administración & dosificación , Vitaminas/metabolismo , Animales , Ácido Ascórbico/orina , Dieta , Ingestión de Alimentos/efectos de los fármacos , Metabolismo Energético , Hígado/química , Masculino , Niacina/orina , Niacinamida/orina , Tamaño de los Órganos/efectos de los fármacos , Ácido Pantoténico/efectos adversos , Ácido Pantoténico/análisis , Ácido Pantoténico/sangre , Ácido Pantoténico/orina , Ácido Piridóxico/orina , Ratas , Ratas Wistar , Riboflavina/orina , Solubilidad , Tiamina/orina , Vitamina B 6/orina , Complejo Vitamínico B/orina , Agua , Aumento de Peso/efectos de los fármacos
16.
Am J Clin Nutr ; 80(4): 946-51, 2004 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15447904

RESUMEN

BACKGROUND: Although many studies have reported reduced vitamin B-6 status with aging, little information is available about the specific effects of menopause. OBJECTIVE: We aimed to examine vitamin B-6 metabolism in premenopausal and early postmenopausal women. DESIGN: We examined dietary intake and vitamin B-6 metabolites in the plasma, erythrocytes, and urine of 30 premenopausal women (x +/- SD age: 41.9 +/- 4.8 y) and 30 women (aged 54.0 +/- 3.8 y) who were 4.0 +/- 1.4 y past menopause. RESULTS: Vitamin B-6 intake in the postmenopausal group (1.97 +/- 0.40 mg/d) was significantly greater than that in the premenopausal group (1.63 +/- 0.50 mg/d). Plasma pyridoxal phosphate (PLP) and pyridoxal concentrations and erythrocyte PLP, pyridoxal, and pyridoxamine phosphate concentrations were in the normal range in both groups and did not differ significantly between the 2 groups. Plasma and erythrocyte 4-pyridoxic acid (4-PA) concentrations were significantly higher in the postmenopausal group than in the premenopausal group, which may have been due at least partly to the slightly higher vitamin B-6 intake of the former group. Erythrocyte 4-PA was correlated (r = -0.37, P < 0.01) with serum estradiol in both groups. Urinary 4-PA did not differ significantly between the 2 groups. The serum phosphate concentration was higher in the postmenopausal group than in the premenopausal group, and it was correlated (r = 0.40, P < 0.01) with plasma PLP. Inhibition of alkaline phosphatase by the increased phosphate may help to increase plasma PLP. CONCLUSION: Menopause may not necessarily be associated with a decrease in vitamin B-6 status.


Asunto(s)
Estradiol/sangre , Posmenopausia/metabolismo , Ácido Piridóxico/sangre , Ácido Piridóxico/orina , Vitamina B 6/sangre , Vitamina B 6/orina , Adulto , Envejecimiento/metabolismo , Eritrocitos/química , Femenino , Humanos , Persona de Mediana Edad , Estado Nutricional , Posmenopausia/sangre , Posmenopausia/orina , Fosfato de Piridoxal/sangre , Fosfato de Piridoxal/metabolismo , Piridoxina/sangre , Piridoxina/metabolismo , Vitamina B 6/administración & dosificación
17.
J Nutr ; 133(10): 3191-4, 2003 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-14519809

RESUMEN

Because of limited available information, the Estimated Average Requirement (EAR) and Recommended Dietary Allowance (RDA) of vitamin B-6 for adolescents were recently estimated by extrapolation from adult values. To determine vitamin B-6 requirements and to provide recommendations for intakes, vitamin B-6 intake, nutritional status and anthropometry were studied in 134 healthy adolescents (63 boys and 71 girls) aged 13-15 y in Tainan, Taiwan. Direct and indirect vitamin B-6 indicators were measured in plasma, erythrocytes and urine. The anthropometric data of the adolescents in this study were similar to those of the first Nutrition and Health Survey in Taiwan (NAHSIT), conducted from 1993 to 1996, showing the normal growth and development of this adolescent group. All subjects had plasma pyridoxal-5'-phosphate (PLP) concentrations > or = 20 nmol/L, indicating an adequate vitamin B-6 status. The mean dietary vitamin B-6 intakes of boys and girls were 1.04 +/- 0.24 and 0.83 +/- 0.26 mg/d, respectively. Vitamin B-6 status indicators, including plasma PLP, erythrocyte alanine activity coefficient (EALT-AC), aspartate aminotransferase activity coefficient (EAST-AC) and urinary 4-pyridoxic acid (4-PA), were correlated with vitamin B-6 intake (r = 0.84, -0.84, -0.77 and 0.86, respectively, P < 0.01). Adequate values of plasma PLP (> or = 20 nmol/L), EALT-AC (<1.25), EAST-AC (<1.8) and urinary 4-PA (>3.0 micromol/d) were used to determine the EAR according to the Dietary Reference Intake committee methodology. The present study suggests that vitamin B-6 EAR (RDA) for adolescent boys and girls aged 13-15 y are 1.07 (1.28) and 0.90 (1.08) mg/d, respectively.


Asunto(s)
Antropometría , Dieta , Necesidades Nutricionales , Estado Nutricional , Vitamina B 6/administración & dosificación , Adolescente , Alanina/sangre , Aspartato Aminotransferasas/sangre , Eritrocitos/química , Femenino , Humanos , Masculino , Política Nutricional , Fosfato de Piridoxal/sangre , Ácido Piridóxico/orina , Taiwán , Vitamina B 6/sangre , Vitamina B 6/orina
18.
Eur J Nutr ; 42(2): 84-90, 2003 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12638029

RESUMEN

BACKGROUND: Exclusion of animal products and having only plant protein in vegetarian diets may affect the status of certain B-vitamins, and further cause the elevation of plasma homocysteine concentration. AIM: The purpose of this study was to assess the status of homocysteine and related B-vitamins in vegetarians and nonvegetarians. The effects of biochemical parameters of B-vitamins and dietary protein on plasma homocysteine were also examined. METHODS: The study was performed at the Chung Shan Medical University, Taichung, in the central part of Taiwan. Thirty-seven vegetarians (28.9 +/- 5.5 y) and 32 nonvegetarians (22.9 +/- 1.6 y) were recruited. Nutrient intake was recorded using 3-day dietary records. Fasting venous blood samples were obtained. Plasma homocysteine, folate and vitamin B-12 were measured. Vitamin B-6 status was assessed by direct measures [plasma pyridoxal 5'-phosphate (PLP) and urinary 4-pyridoxic acid (4-PA)] and indirect measures [erythrocyte alanine (EALT-AC) and aspartate (EAST-AC) aminotransaminase activity coefficient]. RESULTS: There was no significant difference in vitamin B-6 intake between the two groups, although the vegetarian group had a significantly lower vitamin B-12 intake than the nonvegetarian group. Vegetarian subjects had significantly lower mean plasma PLP and vitamin B-12 concentrations than did nonvegetarian subjects (p < 0.05); however, a significantly higher mean plasma folate concentration was found in the vegetarian group. Vegetarian subjects had a significantly higher mean plasma homocysteine concentration than nonvegetarian subjects (13.2 +/- 7.9 vs. 9.8 +/- 2.2 micromol/L). Negative correlations were seen between plasma homocysteine and vitamin B-12 concentrations in the vegetarian (p = 0.004), nonvegetarian (p = 0.026), and pooled (p < 0.001) groups. From best subsets regression analyses, the plasma homocysteine concentration could be significantly predicted by total protein intake (p = 0.027) and plasma vitamin B-12 concentration (p = 0.005) in the pooled group. When the intake of protein is not considered, vitamin B-12 concentration is still a strong predictor of plasma homocysteine concentration (p = 0.012). CONCLUSIONS: Vitamin B-12 intake and mean plasma vitamin B-12 concentration were lower for vegetarian subjects than for nonvegetarian subjects, leading to an increase in plasma homocysteine concentration. Vitamin B-6 and folate had little effect on plasma homocysteine concentration when individuals had adequate vitamin B-6 and folate status.


Asunto(s)
Dieta Vegetariana/estadística & datos numéricos , Homocisteína/sangre , Estado Nutricional/fisiología , Vitamina B 12/sangre , Vitamina B 6/sangre , Adulto , Proteínas en la Dieta/metabolismo , Femenino , Ácido Fólico/sangre , Humanos , Masculino , Valores de Referencia , Análisis de Regresión , Vitamina B 6/orina
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