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1.
J Hepatol ; 79(4): 955-966, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37328069

RESUMO

BACKGROUND AND AIMS: We previously demonstrated that people with primary sclerosing cholangitis (PSC) had reduced gut microbial capacity to produce active vitamin B6 (pyridoxal 5'-phosphate [PLP]), which corresponded to lower circulating PLP levels and poor outcomes. Here, we define the extent and biochemical and clinical impact of vitamin B6 deficiency in people with PSC from several centers before and after liver transplantation (LT). METHODS: We used targeted liquid chromatography-tandem mass spectrometry to measure B6 vitamers and B6-related metabolic changes in blood from geographically distinct cross-sectional cohorts totaling 373 people with PSC and 100 healthy controls to expand on our earlier findings. Furthermore, we included a longitudinal PSC cohort (n = 158) sampled prior to and serially after LT, and cohorts of people with inflammatory bowel disease (IBD) without PSC (n = 51) or with primary biliary cholangitis (PBC) (n = 100), as disease controls. We used Cox regression to measure the added value of PLP to predict outcomes before and after LT. RESULTS: In different cohorts, 17-38% of people with PSC had PLP levels below the biochemical definition of a vitamin B6 deficiency. The deficiency was more pronounced in PSC than in IBD without PSC and PBC. Reduced PLP was associated with dysregulation of PLP-dependent pathways. The low B6 status largely persisted after LT. Low PLP independently predicted reduced LT-free survival in both non-transplanted people with PSC and in transplant recipients with recurrent disease. CONCLUSIONS: Low vitamin B6 status with associated metabolic dysregulation is a persistent feature of PSC. PLP was a strong prognostic biomarker for LT-free survival both in PSC and recurrent disease. Our findings suggest that vitamin B6 deficiency modifies the disease and provides a rationale for assessing B6 status and testing supplementation. IMPACT AND IMPLICATIONS: We previously found that people with PSC had reduced gut microbial potential to produce essential nutrients. Across several cohorts, we find that the majority of people with PSC are either vitamin B6 deficient or have a marginal deficiency, which remains prevalent even after liver transplantation. Low vitamin B6 levels strongly associate with reduced liver transplantation-free survival as well as deficits in biochemical pathways dependent on vitamin B6, suggesting that the deficiency has a clinical impact on the disease. The results provide a rationale for measuring vitamin B6 and to investigate whether vitamin B6 supplementation or modification of the gut microbial community can help improve outcomes for people with PSC.


Assuntos
Colangite Esclerosante , Doenças Inflamatórias Intestinais , Deficiência de Vitamina B 6 , Humanos , Deficiência de Vitamina B 6/complicações , Colangite Esclerosante/complicações , Colangite Esclerosante/cirurgia , Estudos Transversais , Vitamina B 6 , Doenças Inflamatórias Intestinais/complicações , Fígado
2.
Food Nutr Res ; 672023.
Artigo em Inglês | MEDLINE | ID: mdl-38187791

RESUMO

Pyridoxal 5´-phosphate (PLP) is the main form of vitamin B6 in animal tissue and functions as a coenzyme for more than 160 different enzymatic reactions in the metabolism of amino acids, carbohydrates, lipids, and neurotransmitters. Estimated dietary intake of vitamin B6 and plasma PLP values differ a lot between studies, something which may be due to variable use of supplements, variations in dietary assessment and analytical methods. These factors make it difficult to achieve precise data for setting a correct recommended intake of vitamin B6. In addition, a plasma PLP concentration of 30 nmol/L is considered to be sufficient and the current recommendations for vitamin B6 intake is based on this concept. However, the metabolic marker for vitamin B6 status, HK ratio (HKr), starts to increase already when plasma PLP falls below 100 nmol/L and increases more steeply below 50 nmol/L, indicating biochemical deficiency. Consequently, a plasma PLP concentration of 30 nmol/L, may be too low as a marker for an adequate vitamin B6 status.

3.
Am J Clin Nutr ; 114(1): 338-347, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-33829249

RESUMO

BACKGROUND: Vitamin B6 insufficiency has been linked to increased risk of cancer and other chronic diseases. The circulating concentration of pyridoxal 5'-phosphate (PLP) is a commonly used measure of vitamin B6 status. Ratios of substrates indicating PLP coenzymatic function and metabolism may be useful complementary measures to further explore the role of vitamin B6 in health. OBJECTIVES: We explored the sensitivity of 5 outcomes, namely PLP concentration, homocysteine:cysteine (Hcy:Cys), cystathionine:cysteine (Cysta:Cys), the 3´-hydroxykynurenine ratio (HKr), and the 4-pyridoxic acid ratio (PAr) to vitamin B6 intake as well as personal and lifestyle characteristics. MEDTHODS: Dietary intake and biomarker data were collected from participants from 3 nested case-control studies within the European Prospective Investigation into Cancer and Nutrition (EPIC). Bayesian regression models assessed the associations of the 5 biomarker outcomes with vitamin B6 intake and personal and lifestyle covariates. Analogous models examined the relations of Hcy:Cys, Cysta:Cys, and HKr with PLP. RESULTS: In total, 4608 participants were included in the analyses. Vitamin B6 intake was most strongly associated with PLP, moderately associated with Hcy:Cys, Cysta:Cys, and HKr, and not associated with PAr (fold change in marker given a doubling of vitamin B6 intake: PLP 1.60 [95% credible interval (CrI): 1.50, 1.71]; Hcy:Cys 0.87 [95% CrI: 0.84, 0.90]; Cysta:Cys 0.89 [95% CrI: 0.84, 0.94]; HKr 0.88 [95% CrI: 0.85, 0.91]; PAr 1.00 [95% CrI: 0.95, 1.05]). PAr was most sensitive to age, and HKr was least sensitive to BMI and alcohol intake. Sex and menopause status were strongly associated with all 5 markers. CONCLUSIONS: We found that 5 different markers, capturing different aspects of vitamin B6-related biological processes, varied in their associations with vitamin B6 intake and personal and lifestyle predictors.


Assuntos
Neoplasias/epidemiologia , Neoplasias/etiologia , Vitamina B 6/sangue , Idoso , Estudos de Casos e Controles , Europa (Continente) , Feminino , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Estado Nutricional , Deficiência de Vitamina B 6
4.
Nutrients ; 12(5)2020 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-32429429

RESUMO

Large quantities of protein-rich cod residuals, which are currently discarded, could be utilized for human consumption. Although fish fillet intake is related to beneficial health effects, little is known about the potential health effects of consuming cod residual protein powder. Fifty lean adults were randomized to consume capsules with 8.1 g/day of cod residual protein (Cod-RP) or placebo capsules (Control group) for eight weeks, in this randomized, double-blind study. The intervention was completed by 40 participants. Fasting glucose and insulin concentrations were unaffected by Cod-RP supplementation, whereas plasma concentrations of α-hydroxybutyrate, ß-hydroxybutyrate and acetoacetate all were decreased compared with the Control group. Trimethylamine N-oxide concentration in plasma and urine were increased in the Cod-RP group compared with the Control group. To conclude, the reduction in these potential early markers of impaired glucose metabolism following Cod-RP supplementation may indicate beneficial glucoregulatory effects of cod residual proteins. Trimethylamine N-oxide appears to be an appropriate biomarker of cod residual protein intake in lean adults.


Assuntos
Glicemia/efeitos dos fármacos , Suplementos Nutricionais , Proteínas de Peixes da Dieta/administração & dosagem , Gadiformes , Adulto , Animais , Biomarcadores/sangue , Biomarcadores/urina , Método Duplo-Cego , Jejum/sangue , Jejum/urina , Feminino , Humanos , Masculino , Metilaminas/sangue , Metilaminas/urina , Pessoa de Meia-Idade
5.
Eur J Clin Nutr ; 74(9): 1306-1315, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32317749

RESUMO

BACKGROUND/OBJECTIVES: Folates found in natural foods are thought to protect against cancer. However, folic acid (FA), a synthetic form of folate used in supplements and fortified foods, may increase breast cancer risk if present in unmetabolized form (UMFA) in the circulation. This study examined the associations of serum UMFA and 5-methyltetrahydrofolate (5-mTHF), the predominant form of circulating folate, with breast cancer risk. SUBJECTS/METHODS: We conducted a nested case-control study in a prospective cohort. In total, 553 cases of invasive breast cancer, diagnosed before mandatory FA fortification of grain in the US in 1998, were individually-matched to 1059 controls. Serum UMFA and 5-mTHF were measured using liquid chromatography-tandem mass spectrometry in stored serum samples, and 5-mTHF was corrected for storage degradation. RESULTS: Serum UMFA was not associated with breast cancer risk: the percentage of women with detectable levels of UMFA was similar in cases and controls (18% and 20%, respectively; p = 0.46). Two tag-SNPs in the promoter region of the FA-metabolizing gene were also not associated with risk. There was a marginally significant inverse association of 5-mTHFcorrected with breast cancer risk (odds ratio for the highest vs. lowest quintile = 0.69, 95% CI = 0.49 to 0.97; ptrend = 0.08). CONCLUSIONS: Circulating UMFA was not associated with breast cancer risk. These results apply to countries without mandatory FA food fortification. Studies are needed in countries with mandatory fortification, where levels of UMFA are much higher than in our study.


Assuntos
Neoplasias da Mama , Ácido Fólico , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/etiologia , Estudos de Casos e Controles , Feminino , Humanos , Estudos Prospectivos , Tetra-Hidrofolatos
6.
PLoS One ; 15(1): e0227384, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31923274

RESUMO

Chronic cancer-related fatigue (CF) is a common and distressing condition in a subset of cancer survivors and common also after successful treatment of malignant lymphoma. The etiology and pathogenesis of CF is unknown, and lack of biomarkers hampers development of diagnostic tests and successful therapy. Recent studies on the changes of amino acid levels and other metabolites in patients with chronic fatigue syndrome/myalgic encephalopathy (CFS/ME) have pointed to possible central defects in energy metabolism. Here we report a comprehensive analysis of serum concentrations of amino acids, including metabolites of tryptophan, the kynurenine pathway and vitamin B6 in a well characterized national Norwegian cohort of lymphoma survivors after high-dose therapy and autologous stem cell transplantation. Among the 20 standard amino acids in humans, only tryptophan levels were significantly lower in both males and females with CF compared to non-fatigued survivors, a strikingly different pattern than seen in CFS/ME. Markers of tryptophan degradation by the kynurenine pathway (kynurenine/tryptophan ratio) and activation of vitamin B6 catabolism (pyridoxic acid/(pyridoxal + pyridoxal 5'-phosphate), PAr index) differed in survivors with or without CF and correlated with known markers of immune activation and inflammation, such as neopterin, C-reactive protein and Interleukin-6. Among personal traits and clinical findings assessed simultaneously in participating survivors, higher neuroticism score, obesity and higher PAr index were significantly associated with increased risk of CF. Collectively, these data point to low grade immune activation and inflammation as a basis for CF in lymphoma survivors.


Assuntos
Aminoácidos/metabolismo , Síndrome de Fadiga Crônica/etiologia , Linfoma/complicações , Vitamina B 6/metabolismo , Adolescente , Adulto , Idoso , Aminoácidos/sangue , Sobreviventes de Câncer , Criança , Síndrome de Fadiga Crônica/sangue , Síndrome de Fadiga Crônica/metabolismo , Síndrome de Fadiga Crônica/psicologia , Feminino , Humanos , Inflamação/sangue , Linfoma/metabolismo , Linfoma/psicologia , Linfoma/terapia , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Triptofano/metabolismo , Vitamina B 6/sangue , Adulto Jovem
7.
Am J Clin Nutr ; 109(5): 1239-1250, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-31051508

RESUMO

BACKGROUND: Replacing dietary saturated fatty acids (SFAs) with polyunsaturated fatty acids (PUFA) reduces the plasma low-density lipoprotein (LDL) cholesterol and subsequently the risk of cardiovascular disease. However, beyond changes in LDL cholesterol, we lack a complete understanding of the physiologic alterations that occur when improving dietary fat quality. OBJECTIVES: The aim of this study was to gain knowledge of metabolic alterations paralleling improvements in the fat quality of the diet. METHODS: We recently conducted an 8-wk, double-blind, randomized controlled trial replacing SFAs with PUFAs in healthy subjects with moderate hypercholesterolemia (n = 99). In the present substudy, we performed comprehensive metabolic profiling with multiple platforms (both nuclear magnetic resonance- and mass spectrometry-based technology) (n = 99), and analyzed peripheral blood mononuclear cell gene expression (n = 95) by quantitative real-time polymerase chain reaction. RESULTS: A large number of lipoprotein subclasses, myristoylcarnitine and palmitoylcarnitine, and kynurenine were reduced when SFAs were replaced with PUFAs. In contrast, bile acids, proprotein convertase subtilisin/kexin type 9, acetate, and acetoacetate were increased by the intervention. Some amino acids were also altered by the intervention. The mRNA levels of LXRA and LDLR were increased, in addition to several liver X receptor α target genes and genes involved in inflammation, whereas the mRNA levels of UCP2 and PPARD were decreased in peripheral blood mononuclear cells after replacing SFAs with PUFAs. Partial least squares-discriminant analysis showed that the 30 most important variables that contributed to class separation spanned all classes of biomarkers, and was in accordance with the univariate analysis. CONCLUSIONS: Applying metabolomics in randomized controlled dietary intervention trials has the potential to extend our knowledge of the biological and molecular effects of dietary fat quality. This study was registered at clinicaltrials.gov as NCT01679496.


Assuntos
Dieta , Gorduras na Dieta/farmacologia , Ácidos Graxos Insaturados/farmacologia , Comportamento Alimentar , Hipercolesterolemia/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Lipoproteínas/sangue , Ácido Acético/sangue , Acetoacetatos/sangue , Aminoácidos/sangue , Ácidos e Sais Biliares/sangue , LDL-Colesterol/sangue , Gorduras na Dieta/administração & dosagem , Gorduras na Dieta/efeitos adversos , Gorduras na Dieta/sangue , Método Duplo-Cego , Ácidos Graxos/administração & dosagem , Ácidos Graxos/sangue , Ácidos Graxos/farmacologia , Ácidos Graxos Insaturados/administração & dosagem , Ácidos Graxos Insaturados/sangue , Ácidos Graxos Insaturados/uso terapêutico , Feminino , Perfilação da Expressão Gênica/métodos , Humanos , Hipercolesterolemia/dietoterapia , Hipercolesterolemia/genética , Masculino , Metaboloma/efeitos dos fármacos , Metabolômica/métodos , Pessoa de Meia-Idade , Peptídeo Hidrolases/genética , Peptídeo Hidrolases/metabolismo
8.
Nutrients ; 10(5)2018 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-29783689

RESUMO

Cobalamin and folate are crucial micronutrients during infancy and they are required for growth and cognitive development. Due to the monotonous and predominantly vegetarian-based complementary feeding and poor maternal micronutrient status, infants from low- and middle-income countries are susceptible to cobalamin deficiency. However, data on plasma cobalamin and folate and the functional markers methylmalonic acid and total homocysteine from breastfed infants in Nepal are still needed. We collected plasma samples from 316 6⁻11-month-old breastfed infants with a length-for-age of less than minus one z-score and analyzed blood for plasma folate, cobalamin, methylmalonic acid and total homocysteine concentrations. Cobalamin deficiency (plasma cobalamin 10 µmol/L) and methylmalonic acid (>0.28 µmol/L) indicating functional cobalamin deficiency were found among 53% and 75% of the infants, respectively. Based on a combined indicator of cobalamin status, 58% were found to have low cobalamin status. However, folate deficiency (.


Assuntos
Aleitamento Materno , Ácido Fólico/sangue , Fenômenos Fisiológicos da Nutrição do Lactente , Vitamina B 12/sangue , Biomarcadores/sangue , Estudos Transversais , Feminino , Deficiência de Ácido Fólico/sangue , Deficiência de Ácido Fólico/diagnóstico , Homocisteína/sangue , Humanos , Lactente , Masculino , Ácido Metilmalônico/sangue , Nepal , Estado Nutricional , Deficiência de Vitamina B 12/sangue , Deficiência de Vitamina B 12/diagnóstico
9.
Nutrients ; 9(12)2017 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-29240677

RESUMO

Arginine is a constituent of proteins and a precursor for polyamines and nitric oxide, and is essential for placentation, angiogenesis, and growth. Maternal plasma arginine concentrations are found to be lower in pregnancies complicated by fetal growth restriction, and arginine supplementation in later pregnancy is reported to increase birth weight. We measured arginine and the metabolites asymmetric dimethylarginine (ADMA) and symmetric dimethylarginine (SDMA) in the amniotic fluid obtained in pregnancy weeks 13 to 15 from 363 pregnancies with a documented normal outcome and related the concentrations to birth weight, length, and head circumference. Arginine was higher in the amniotic fluid from female (mean 40.8 (SD 10.6) µmol/L) compared to male fetuses (37.4 (SD 11.2) µmol/L, p = 0.003). Despite the gender difference, arginine in the amniotic fluid from gestational weeks 13-15 was the strongest predictor for birth weight, length, and head circumference. ADMA was a strong predictor for birth weight and length, SDMA for birth weight, while Arg/ADMA and Arg/SDMA only predicted head circumference in multiple linear regression models. Due to increased arginine demands, pregnancy is considered a state of relative arginine deficiency. Our findings reflect the importance of a good maternal arginine status in early pregnancy, an observation that should be evaluated in an intervention study.


Assuntos
Líquido Amniótico/química , Arginina/análise , Peso ao Nascer , Adulto , Arginina/análogos & derivados , Arginina/deficiência , Suplementos Nutricionais , Feminino , Retardo do Crescimento Fetal , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Óxido Nítrico/metabolismo , Gravidez , Trimestres da Gravidez , Adulto Jovem
10.
Nat Rev Dis Primers ; 3: 17040, 2017 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-28660890

RESUMO

Vitamin B12 (B12; also known as cobalamin) is a B vitamin that has an important role in cellular metabolism, especially in DNA synthesis, methylation and mitochondrial metabolism. Clinical B12 deficiency with classic haematological and neurological manifestations is relatively uncommon. However, subclinical deficiency affects between 2.5% and 26% of the general population depending on the definition used, although the clinical relevance is unclear. B12 deficiency can affect individuals at all ages, but most particularly elderly individuals. Infants, children, adolescents and women of reproductive age are also at high risk of deficiency in populations where dietary intake of B12-containing animal-derived foods is restricted. Deficiency is caused by either inadequate intake, inadequate bioavailability or malabsorption. Disruption of B12 transport in the blood, or impaired cellular uptake or metabolism causes an intracellular deficiency. Diagnostic biomarkers for B12 status include decreased levels of circulating total B12 and transcobalamin-bound B12, and abnormally increased levels of homocysteine and methylmalonic acid. However, the exact cut-offs to classify clinical and subclinical deficiency remain debated. Management depends on B12 supplementation, either via high-dose oral routes or via parenteral administration. This Primer describes the current knowledge surrounding B12 deficiency, and highlights improvements in diagnostic methods as well as shifting concepts about the prevalence, causes and manifestations of B12 deficiency.


Assuntos
Deficiência de Vitamina B 12/diagnóstico , Deficiência de Vitamina B 12/epidemiologia , Vitamina B 12/sangue , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores , Criança , Pré-Escolar , Feminino , Homocisteína/metabolismo , Humanos , Masculino , Ácido Metilmalônico/metabolismo , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Transcobalaminas/metabolismo , Vitamina B 12/metabolismo , Deficiência de Vitamina B 12/complicações , Deficiência de Vitamina B 12/metabolismo , Adulto Jovem
11.
Nutrients ; 9(7)2017 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-28661435

RESUMO

Background: Traditionally, vitamin B1 status is assessed by a functional test measuring erythrocyte transketolase (ETK) activity or direct measurement of erythrocyte thiamine diphosphate (eThDP) concentration. However, such analyses are logistically challenging, and do not allow assessment of vitamin B1 status in plasma/serum samples stored in biobanks. Using a multiplex assay, we evaluated plasma concentrations of thiamine and thiamine monophosphate (TMP), as alternative, convenient measures of vitamin B1 status. Methods: We investigated the relationships between the established biomarker eThDP and plasma concentrations of thiamine and TMP, and compared the response of these thiamine forms to thiamine fortification using samples from 196 healthy Cambodian women (aged 18-45 years.). eThDP was measured by high performance liquid chromatography with fluorescence detection (HPLC-FLD) and plasma thiamine and TMP by high performance liquid chromatography-tandem mass spectrometry (LC-MS/MS). Results: Plasma thiamine and TMP correlated significantly with eThDP at baseline and study-end (p < 0.05). Among the fortification groups, the strongest response was observed for plasma thiamine (increased by 266%), while increases in plasma TMP (60%) and eThDP (53%) were comparable. Conclusions: Plasma thiamine and TMP correlated positively with eThDP, and all thiamine forms responded significantly to thiamine intervention. Measuring plasma concentrations of thiamine forms is advantageous due to convenient sample handling and capacity to develop low volume, high-throughput, multiplex assays.


Assuntos
Eritrócitos/química , Alimentos Fortificados , Deficiência de Tiamina/prevenção & controle , Tiamina Pirofosfato/metabolismo , Tiamina/sangue , Tiamina/farmacologia , Adulto , Povo Asiático , Camboja , Cromatografia Líquida , Feminino , Humanos , Espectrometria de Massas em Tandem , Deficiência de Tiamina/epidemiologia , Tiamina Pirofosfato/química
12.
Mol Aspects Med ; 53: 10-27, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27593095

RESUMO

The active form of vitamin B6, pyridoxal 5'-phosphate (PLP), serves as a co-factor in more than 150 enzymatic reactions. Plasma PLP has consistently been shown to be low in inflammatory conditions; there is a parallel reduction in liver PLP, but minor changes in erythrocyte and muscle PLP and in functional vitamin B6 biomarkers. Plasma PLP also predicts the risk of chronic diseases like cardiovascular disease and some cancers, and is inversely associated with numerous inflammatory markers in clinical and population-based studies. Vitamin B6 intake and supplementation improve some immune functions in vitamin B6-deficient humans and experimental animals. A possible mechanism involved is mobilization of vitamin B6 to the sites of inflammation where it may serve as a co-factor in pathways producing metabolites with immunomodulating effects. Relevant vitamin B6-dependent inflammatory pathways include vitamin B6 catabolism, the kynurenine pathway, sphingosine 1-phosphate metabolism, the transsulfuration pathway, and serine and glycine metabolism.


Assuntos
Inflamação/tratamento farmacológico , Vitamina B 6/uso terapêutico , Animais , Biomarcadores/sangue , Humanos , Imunidade/efeitos dos fármacos , Inflamação/imunologia , Fosfato de Piridoxal/química , Fosfato de Piridoxal/metabolismo , Transdução de Sinais , Vitamina B 6/química
13.
Nutrients ; 8(12)2016 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-28009810

RESUMO

BACKGROUND: Describing vitamin D status and its predictors in various populations is important in order to target public health measures. OBJECTIVES: To describe the status and predictors of vitamin D status in healthy Nepalese mothers and infants. METHODS: 500 randomly selected Nepalese mother and infant pairs were included in a cross-sectional study. Plasma 25(OH)D concentrations were measured by LC-MS/MS and multiple linear regression analyses were used to identify predictors of vitamin D status. RESULTS: Among the infants, the prevalence of vitamin D insufficiency (25(OH)D <50 nmol/L) and deficiency (<30 nmol/L) were 3.6% and 0.6%, respectively, in contrast to 59.8% and 14.0% among their mothers. Infant 25(OH)D concentrations were negatively associated with infant age and positively associated with maternal vitamin D status and body mass index (BMI), explaining 22% of the variability in 25(OH)D concentration. Global solar radiation, maternal age and BMI predicted maternal 25(OH)D concentration, explaining 9.7% of its variability. CONCLUSION: Age and maternal vitamin D status are the main predictors of vitamin D status in infants in Bhaktapur, Nepal, who have adequate vitamin D status despite poor vitamin D status in their mothers.


Assuntos
Fenômenos Fisiológicos da Nutrição do Lactente , Saúde Materna , Estado Nutricional , Deficiência de Vitamina D/epidemiologia , Vitamina D/análogos & derivados , Adolescente , Adulto , Biomarcadores/sangue , Índice de Massa Corporal , Cromatografia Líquida , Estudos Transversais , Feminino , Humanos , Lactente , Lactação/sangue , Modelos Lineares , Masculino , Idade Materna , Nepal/epidemiologia , Prevalência , Fatores de Risco , Luz Solar , Espectrometria de Massas em Tandem , Vitamina D/sangue , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/diagnóstico , Adulto Jovem
14.
Eur Urol ; 70(6): 941-951, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27061263

RESUMO

BACKGROUND: Folate and vitamin B12 are essential for maintaining DNA integrity and may influence prostate cancer (PCa) risk, but the association with clinically relevant, advanced stage, and high-grade disease is unclear. OBJECTIVE: To investigate the associations between circulating folate and vitamin B12 concentrations and risk of PCa overall and by disease stage and grade. DESIGN, SETTING, AND PARTICIPANTS: A study was performed with a nested case-control design based on individual participant data from six cohort studies including 6875 cases and 8104 controls; blood collection from 1981 to 2008, and an average follow-up of 8.9 yr (standard deviation 7.3). Odds ratios (ORs) of incident PCa by study-specific fifths of circulating folate and vitamin B12 were calculated using multivariable adjusted conditional logistic regression. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Incident PCa and subtype by stage and grade. RESULTS AND LIMITATIONS: Higher folate and vitamin B12 concentrations were associated with a small increase in risk of PCa (ORs for the top vs bottom fifths were 1.13 [95% confidence interval (CI), 1.02-1.26], ptrend=0.018, for folate and 1.12 [95% CI, 1.01-1.25], ptrend=0.017, for vitamin B12), with no evidence of heterogeneity between studies. The association with folate varied by tumour grade (pheterogeneity<0.001); higher folate concentration was associated with an elevated risk of high-grade disease (OR for the top vs bottom fifth: 2.30 [95% CI, 1.28-4.12]; ptrend=0.001), with no association for low-grade disease. There was no evidence of heterogeneity in the association of folate with risk by stage or of vitamin B12 with risk by stage or grade of disease (pheterogeneity>0.05). Use of single blood-sample measurements of folate and B12 concentrations is a limitation. CONCLUSIONS: The association between higher folate concentration and risk of high-grade disease, not evident for low-grade disease, suggests a possible role for folate in the progression of clinically relevant PCa and warrants further investigation. PATIENT SUMMARY: Folate, a vitamin obtained from foods and supplements, is important for maintaining cell health. In this study, however, men with higher blood folate levels were at greater risk of high-grade (more aggressive) prostate cancer compared with men with lower folate levels. Further research is needed to investigate the possible role of folate in the progression of this disease.


Assuntos
Ácido Fólico/sangue , Neoplasias da Próstata/sangue , Vitamina B 12/sangue , Idoso , Estudos de Casos e Controles , Estudos de Coortes , Hexitidina , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Neoplasias da Próstata/epidemiologia , Risco
15.
BMC Pediatr ; 15: 218, 2015 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-26678525

RESUMO

BACKGROUND: Exclusive breastfeeding for 6 months is assumed to ensure adequate micronutrients for term infants. Our objective was to investigate the effects of prolonged breastfeeding on B vitamin status and neurodevelopment in 80 infants with subnormal birth weights (2000-3000 g) and examine if cobalamin supplementation may benefit motor function in infants who developed biochemical signs of impaired cobalamin function (total homocysteine (tHcy) > 6.5 µmol/L) at 6 months. METHODS: Levels of cobalamin, folate, riboflavin and pyridoxal 5´-phosphate, and the metabolic markers tHcy and methylmalonic acid (MMA), were determined at 6 weeks, 4 and 6 months (n = 80/68/66). Neurodevelopment was assessed with the Alberta Infants Motor Scale (AIMS) and the parental questionnaire Ages and Stages (ASQ) at 6 months. At 6 months, 32 of 36 infants with tHcy > 6.5 µmol/L were enrolled in a double blind randomized controlled trial to receive 400 µg hydroxycobalamin intramuscularly (n = 16) or sham injection (n = 16). Biochemical status and neurodevelopment were evaluated after one month. RESULTS: Except for folate, infants who were exclusively breastfed for >1 month had lower B vitamin levels at all assessments and higher tHcy and MMA levels at 4 and 6 months. At 6 months, these infants had lower AIMS scores (p = 0.03) and ASQ gross motor scores (p = 0.01). Compared to the placebo group, cobalamin treatment resulted in a decrease in plasma tHcy (p < 0.001) and MMA (p = 0.001) levels and a larger increase in AIMS (p = 0.02) and ASQ gross motor scores (p = 0.03). CONCLUSIONS: The findings suggest that prolonged exclusive breastfeeding may not provide sufficient B vitamins for small infants, and that this may have a negative effect on early gross motor development. In infants with mild cobalamin deficiency at 6 months, cobalamin treatment significantly improvement cobalamin status and motor function, suggesting that the observed impairment in motor function associated with long-term exclusive breastfeeding, may be due to cobalamin deficiency. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, number NCT01201005.


Assuntos
Aleitamento Materno , Desenvolvimento Infantil , Suplementos Nutricionais , Destreza Motora , Deficiência de Vitamina B 12/tratamento farmacológico , Vitamina B 12/uso terapêutico , Complexo Vitamínico B/uso terapêutico , Feminino , Ácido Fólico/sangue , Homocisteína/sangue , Humanos , Lactente , Recém-Nascido de Baixo Peso , Masculino , Ácido Metilmalônico/sangue , Fosfato de Piridoxal/sangue , Riboflavina/sangue , Fatores de Tempo , Vitamina B 12/sangue , Deficiência de Vitamina B 12/sangue
16.
Paediatr Perinat Epidemiol ; 28(3): 270-4, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24506308

RESUMO

BACKGROUND: Maternal folic acid supplementation between subsequent pregnancies may be important to reduce the risk of low folate status associated with short interpregnancy intervals. We examined how the prevalence of preconception folic acid use for a given pregnancy in Norwegian women varied according to the time interval from the previous pregnancy. METHODS: Analysis was based on 48 855 pairs of pregnancies with the second pregnancy included in the Norwegian Mother and Child Cohort Study (birth years 1999-2009). Interpregnancy interval was defined as the time from birth of a child to the conception of the subsequent sibling. Preconception folic acid use was defined as any use of folic acid-containing supplements within the last 4 weeks before the second pregnancy. RESULTS: The prevalence of preconception folic acid use was 31%. Among women with a term birth (≥37 weeks) in the previous pregnancy (92%), those with interpregnancy intervals ≤12 and ≥49 months were associated with up to 35% lower prevalence of preconception folic acid use for the second pregnancy, relative to the reference group (13-24 months). The low use in short intervals was mainly attributable to lower proportion of planned pregnancies and fewer women with higher education. Among women with a preterm birth (<37 weeks) in the previous pregnancy (8%), preconception folic acid use significantly decreased with increasing pregnancy spacing. CONCLUSIONS: Our finding of a lower preconception folic acid use in women with both short and long interpregnancy intervals might help identifying those with higher risk of folate deficiency and preventing unwanted pregnancy outcomes.


Assuntos
Suplementos Nutricionais , Deficiência de Ácido Fólico/complicações , Ácido Fólico/administração & dosagem , Defeitos do Tubo Neural/prevenção & controle , Cuidado Pré-Concepcional , Vitaminas/administração & dosagem , Adulto , Intervalo entre Nascimentos , Feminino , Deficiência de Ácido Fólico/dietoterapia , Seguimentos , Humanos , Recém-Nascido , Masculino , Defeitos do Tubo Neural/epidemiologia , Noruega/epidemiologia , Gravidez , Nascimento Prematuro , Estudos Prospectivos , População Branca
17.
PLoS One ; 8(9): e76720, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24098804

RESUMO

OBJECTIVE: Choline is related to phospholipid metabolism and is a marker for global ischaemia with a small reference range in healthy volunteers. The aim of our study was to characterize the early kinetics of plasma free choline in patients after cardiac arrest. Additionally, we investigated the potential of plasma free choline to predict neurological outcome. METHODS: Twenty patients admitted to our medical intensive care unit were included in this prospective, observational trial. All patients were enrolled between May 2010 and May 2011. They received post cardiac arrest treatment including mild therapeutic hypothermia which was initiated with a combination of cold fluid and a feedback surface cooling device according to current guidelines. Sixteen blood samples per patient were analysed for plasma free choline levels within the first week after resuscitation. Choline was detected by liquid chromatography-tandem mass spectrometry. RESULTS: Most patients showed elevated choline levels on admission (median 14.8 µmol/L; interquartile range; IQR 9.9-20.1) which subsequently decreased. 48 hours after cardiac arrest choline levels in all patients reached subnormal levels at a median of 4.0 µmol/L (IQR 3-4.9; p = 0.001). Subsequently, choline levels normalized within seven days. There was no significant difference in choline levels when groups were analyzed in relation to neurological outcome. CONCLUSIONS: Our data indicate a choline deficiency in the early postresucitation phase. This could potentially result in impaired cell membrane recovery. The detailed characterization of the early choline time course may aid in planning of choline supplementation trials. In a limited number of patients, choline was not promising as a biomarker for outcome prediction.


Assuntos
Biomarcadores/sangue , Colina/sangue , Parada Cardíaca/sangue , Parada Cardíaca/terapia , Hipertermia Induzida/métodos , Isquemia/sangue , Alemanha , Humanos , Isquemia/diagnóstico , Projetos Piloto , Estudos Prospectivos , Estatísticas não Paramétricas
18.
Am J Clin Nutr ; 98(5): 1233-40, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24025626

RESUMO

BACKGROUND: During infancy, minor developmental delays and gastrointestinal complaints are common, as is a biochemical profile indicative of impaired cobalamin status. OBJECTIVE: We investigated whether cobalamin supplementation can improve development or symptoms in infants with biochemical signs of impaired cobalamin function and developmental delay or feeding difficulties. DESIGN: Infants <8 mo of age (n = 105) who were referred for feeding difficulties, subtle neurologic symptoms, or delayed psychomotor development were assessed for cobalamin status [by the measurement of serum cobalamin, plasma total homocysteine (tHcy), and plasma methylmalonic acid (MMA)]. Infants with biochemical signs of impaired cobalamin function, defined as a plasma tHcy concentration ≥6.5 µmol/L (n = 79), were enrolled in a double-blind, randomized controlled trial to receive 400 µg hydroxycobalamin intramuscularly (n = 42) or a sham injection (n = 37). Motor function [Alberta Infants Motor Scale (AIMS)] and clinical symptoms (parental questionnaire) were recorded at entry and after 1 mo. RESULTS: During follow-up, cobalamin supplementation changed all markers of impaired cobalamin status (ie, plasma tHcy decreased by 54%, and MMA decreased by 84%), whereas no significant changes were seen in the placebo group (P < 0.001). The median (IQR) increase in the AIMS score was higher in the cobalamin group than in the placebo group [7.0 (5.0, 9.0) compared with 4.5 (3.3, 6.0); P = 0.003], and a higher proportion showed improvements in regurgitations (69% compared with 29%, respectively; P = 0.003). CONCLUSIONS: In infants with biochemical signs of impaired cobalamin function, 1 intramuscular injection of cobalamin resulted in biochemical evidence of cobalamin repletion and improvement in motor function and regurgitations, which suggest that an adequate cobalamin status is important for a rapidly developing nervous system. This trial was registered at clinicaltrials.gov as NCT00710359 and NCT00710138.


Assuntos
Desenvolvimento Infantil/efeitos dos fármacos , Suplementos Nutricionais , Hidroxocobalamina/administração & dosagem , Vômito/tratamento farmacológico , Biomarcadores/sangue , Método Duplo-Cego , Feminino , Ácido Fólico/sangue , Seguimentos , Homocisteína/sangue , Humanos , Hidroxocobalamina/sangue , Lactente , Injeções Intramusculares , Modelos Lineares , Masculino , Ácido Metilmalônico/sangue , Inquéritos e Questionários , Deficiência de Vitamina B 12/tratamento farmacológico
19.
Pediatr Res ; 74(3): 327-32, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23770919

RESUMO

BACKGROUND: Whereas iron deficiency is considered the leading cause of anemia in infants, cobalamin deficiency is foremost characterized by developmental delay, and the typical macrocytic anemia is confined to severe and longstanding cobalamin deficiency in this age group. Hematological parameters were investigated in 4-mo-old infants with biochemical signs of impaired cobalamin function who participated in a randomized controlled cobalamin intervention study at 6 wk. METHODS: One hundred and seven infants were randomly assigned to receive either an intramuscular injection with 400 µg cobalamin or no intervention at 6 wk. Hematological parameters, and cobalamin and folate status were determined at inclusion and 4 mo. RESULTS: Cobalamin supplementation improved all markers of impaired cobalamin function but had no effect on hematological cell counts at 4 mo (P > 0.18). Signs indicative of an iron-restricted erythropoiesis were observed at 6 wk and 4 mo. At 4 mo, the strongest predictors of low iron status were male gender and a high percentage weight increase from birth. CONCLUSION: In infants with biochemical signs of impaired cobalamin function, supplementation does not improve hematological cell counts. Variations in erythrocyte parameters seem to be foremost associated with iron status in this age group.


Assuntos
Anemia Ferropriva/fisiopatologia , Deficiência de Vitamina B 12/tratamento farmacológico , Deficiência de Vitamina B 12/fisiopatologia , Vitamina B 12/farmacologia , Contagem de Células Sanguíneas , Feminino , Ácido Fólico/sangue , Hemoglobinas/análise , Humanos , Lactente , Injeções Intramusculares , Masculino , Reticulócitos/química , Fatores Sexuais , Vitamina B 12/administração & dosagem , Vitamina B 12/sangue
20.
Pediatr Res ; 73(2): 214-20, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23168578

RESUMO

BACKGROUND: Correct evaluation of iron status is important in young infants because both iron deficiency and excess may have negative effects on development, growth, and morbidity. METHODS: We evaluated iron status using erythrocyte parameters, including reticulocyte hemoglobin content (CHr) in infants with birth weight <3,000 g (n = 80). Blood samples and infant characteristics were recorded at 6 wk and at 4 and 6 months. Infants with a birth weight ≤2,500 g (n = 36) were recommended for iron supplementation. RESULTS: Despite a significantly poorer status at 6 wk, iron-supplemented infants had significantly higher hemoglobin level (Hb): 12.2 (SD = 0.8) g/dl and CHr: 28.3 (SD = 1.4) pg at 6 mo, as compared with nonsupplemented infants, Hb: 11.7 (SD = 1.0) g/dl, P = 0.02 and CHr: 26.5 (SD = 2.5) pg, P < 0.001. Prolonged exclusive breastfeeding, high weight gain, and male gender were the predisposing factors for a low iron status at 6 mo. A CHr cutoff level of 26.9 pg at 4 mo proved to be a sensitive predictor for anemia at 6 mo. CONCLUSION: Signs of an iron-restricted erythropoiesis were observed in nonsupplemented infants (birth weight 2,501-3,000 g), and CHr was a useful tool for evaluating iron status. The need for iron supplementation in certain infant risk populations should be further evaluated.


Assuntos
Anemia Ferropriva/diagnóstico , Eritrócitos/metabolismo , Recém-Nascido de Baixo Peso/sangue , Ferro/sangue , Anemia Ferropriva/sangue , Anemia Ferropriva/tratamento farmacológico , Anemia Ferropriva/etiologia , Biomarcadores/sangue , Peso ao Nascer , Aleitamento Materno , Distribuição de Qui-Quadrado , Suplementos Nutricionais , Contagem de Eritrócitos , Índices de Eritrócitos , Eritrócitos/efeitos dos fármacos , Eritropoese/efeitos dos fármacos , Feminino , Compostos Ferrosos/uso terapêutico , Hemoglobinas/metabolismo , Humanos , Lactente , Recém-Nascido , Masculino , Dinâmica não Linear , Noruega , Valor Preditivo dos Testes , Prognóstico , Reticulócitos/metabolismo , Fatores de Risco , Fatores Sexuais , Fatores de Tempo , Aumento de Peso
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