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1.
J Infect Dis ; 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38877762

RESUMO

In IMPAACT 2010/VESTED, pregnant women were randomized to initiate dolutegravir (DTG)+emtricitabine (FTC)/tenofovir alafenamide (TAF), DTG+FTC/tenofovir disoproxil fumarate (TDF), or efavirenz (EFV)/FTC/TDF. We assessed red blood cell folate concentrations (RBC-folate) at maternal study entry and delivery, and infant birth. RBC-folate outcomes were: 1) maternal change entry to delivery (trajectory), 2) infant, 3) ratio of infant-to-maternal delivery. Generalized estimating equation models for each log(folate) outcome were fit to estimate adjusted geometric mean ratio (Adj-GMR)/GMR trajectories (Adj-GMRT) of each arm comparison in 340 mothers and 310 infants. Overall, 90% of mothers received folic acid supplements and 78% lived in Africa. At entry, median maternal age was 25 years, gestational age was 22 weeks, CD4 count was 482 cells/mm3 and log10HIV RNA was 3 copies/mL. Entry RBC-folate was similar across arms. Adj-GMRT of maternal folate was 3% higher in the DTG+FTC/TAF versus EFV/FTC/TDF arm (1.03, 95%CI 1.00, 1.06). The DTG+FTC/TAF arm had an 8% lower infant-maternal folate ratio (0.92, 95%CI 0.78, 1.09) versus EFV/FTC/TDF. Results are consistent with no clinically meaningful differences between arms for all RBC-folate outcomes and they suggest that cellular uptake of folate and folate transport to the infant do not differ in pregnant women starting DTG- vs. EFV-based ART.

2.
J Pharmacol Exp Ther ; 387(2): 188-203, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37679046

RESUMO

Pompe disease is a rare glycogen storage disorder caused by a deficiency in the lysosomal enzyme acid α-glucosidase, which leads to muscle weakness, cardiac and respiratory failure, and early mortality. Alglucosidase alfa, a recombinant human acid α-glucosidase, was the first approved treatment of Pompe disease, but its uptake into skeletal muscle via the cation-independent mannose-6-phosphate (M6P) receptor (CIMPR) is limited. Avalglucosidase alfa has received marketing authorization in several countries for infantile-onset and/or late-onset Pompe disease. This recently approved enzyme replacement therapy (ERT) was glycoengineered to maximize CIMPR binding through high-affinity interactions with ∼7 bis-M6P moieties. Recently, small molecules like the glucosylceramide synthase inhibitor miglustat were reported to increase the stability of recombinant human acid α-glucosidase, and it was suggested that an increased serum half-life would result in better glycogen clearance. Here, the effects of miglustat on alglucosidase alfa and avalglucosidase alfa stability, activity, and efficacy in Pompe mice were evaluated. Although miglustat increased the stability of both enzymes in fluorescent protein thermal shift assays and when incubated in neutral pH buffer over time, it reduced their enzymatic activity by ∼50%. Improvement in tissue glycogen clearance and transcriptional dysregulation in Pompe mice correlated with M6P levels but not with miglustat coadministration. These results further substantiate the crucial role of CIMPR binding in lysosomal targeting of ERTs. SIGNIFICANCE STATEMENT: This work describes important new insights into the treatment of Pompe disease using currently approved enzyme replacement therapies (ERTs) coadministered with miglustat. Although miglustat increased the stability of ERTs in vitro, there was no positive impact to glycogen clearance and transcriptional correction in Pompe mice. However, increasing mannose-6-phosphate levels resulted in increased cell uptake in vitro and increased glycogen clearance and transcriptional correction in Pompe mice, further underscoring the crucial role of cation-independent mannose-6-phosphate receptor-mediated lysosomal targeting for ERTs.

3.
Mol Genet Metab ; 138(3): 107526, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36774918

RESUMO

Pompe disease is a rare lysosomal storage disorder arising from recessive mutations in the acid α-glucosidase gene and resulting in the accumulation of glycogen, particularly in the cardiac and skeletal muscle. The current standard of care is administration of enzyme replacement therapy in the form of alglucosidase alfa or the recently approved avalglucosidase alfa. In order to better understand the underlying cellular processes that are disrupted in Pompe disease, we conducted gene expression analysis on skeletal muscle biopsies obtained from late-onset Pompe disease patients (LOPD) prior to treatment and following six months of enzyme replacement with avalglucosidase alfa. The LOPD patients had a distinct transcriptomic signature as compared to control patient samples, largely characterized by perturbations in pathways involved in lysosomal function and energy metabolism. Although patients were highly heterogeneous, they collectively exhibited a strong trend towards attenuation of the dysregulated genes following just six months of treatment. Notably, the enzyme replacement therapy had a strong stabilizing effect on gene expression, with minimal worsening in genes that were initially dysregulated. Many of the cellular process that were altered in LOPD patients were also affected in the more clinically severe infantile-onset (IOPD) patients. Additionally, both LOPD and IOPD patients demonstrated enrichment across several inflammatory pathways, despite a lack of overt immune cell infiltration. This study provides further insight into Pompe disease biology and demonstrates the positive effects of avalglucosidase alfa treatment.


Assuntos
Doença de Depósito de Glicogênio Tipo II , Humanos , Doença de Depósito de Glicogênio Tipo II/tratamento farmacológico , Transcriptoma , alfa-Glucosidases/genética , alfa-Glucosidases/uso terapêutico , Músculo Esquelético/patologia , Perfilação da Expressão Gênica , Biópsia , Terapia de Reposição de Enzimas/efeitos adversos
4.
J Nutr ; 153(1): 373-384, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36913474

RESUMO

BACKGROUND: The Vitamin A Laboratory-External Quality Assessment (VITAL-EQA) program operated by the CDC provides analytical performance assessment to low-resource laboratories conducting serum vitamins A (VIA), D (VID), B-12 (B12), and folate (FOL), as well as ferritin (FER) and CRP measurements for public health studies. OBJECTIVES: We aimed to describe the long-term performance of VITAL-EQA participants from 2008 to 2017. METHODS: Participating laboratories received 3 blinded serum samples biannually for duplicate analysis over 3 d. We assessed results (n = 6) for relative difference (%) from the CDC target value and imprecision (% CV) and conducted descriptive statistics on the aggregate 10-year and round-by-round data. Performance criteria were based on biologic variation and deemed acceptable (optimal, desirable, or minimal performance) or unacceptable (less than minimal performance). RESULTS: Thirty-five countries reported VIA, VID, B12, FOL, FER, and CRP results from 2008-2017. The proportion of laboratories with acceptable performance ranged widely by round: VIA 48%-79% (for difference) and 65%-93% (for imprecision), VID 19%-63% and 33%-100%, B12 0%-92% and 73%-100%, FOL 33%-89% and 78%-100%, FER 69%-100% and 73%-100%, and CRP 57%-92% and 87%-100%. On aggregate, ≥60% of laboratories achieved acceptable differences for VIA, B12, FOL, FER, and CRP (only 44% for VID), and over 75% of laboratories achieved acceptable imprecision for all 6 analytes. Laboratories participating continuously in 4 rounds (2016-2017) showed generally similar performance compared to laboratories participating occasionally. CONCLUSIONS: Although we observed little change in laboratory performance over time, on aggregate, >50% of the participating laboratories achieved acceptable performance, with acceptable imprecision being achieved more often than acceptable difference. The VITAL-EQA program is a valuable tool for low-resource laboratories to observe the state of the field and track their own performance over time. However, the small number of samples per round and the constant changes in laboratory participants make it difficult to identify long-term improvements.


Assuntos
Laboratórios , Vitamina A , Humanos , Estados Unidos , Ácido Fólico , Avaliação de Programas e Projetos de Saúde , Centers for Disease Control and Prevention, U.S.
5.
J Nutr ; 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38705470
6.
Proc Natl Acad Sci U S A ; 112(47): 14670-5, 2015 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-26554006

RESUMO

Noninvasive prenatal testing (NIPT) using sequencing of fetal cell-free DNA from maternal plasma has enabled accurate prenatal diagnosis of aneuploidy and become increasingly accepted in clinical practice. We investigated whether NIPT using semiconductor sequencing platform (SSP) could reliably detect subchromosomal deletions/duplications in women carrying high-risk fetuses. We first showed that increasing concentration of abnormal DNA and sequencing depth improved detection. Subsequently, we analyzed plasma from 1,456 pregnant women to develop a method for estimating fetal DNA concentration based on the size distribution of DNA fragments. Finally, we collected plasma from 1,476 pregnant women with fetal structural abnormalities detected on ultrasound who also underwent an invasive diagnostic procedure. We used SSP of maternal plasma DNA to detect subchromosomal abnormalities and validated our results with array comparative genomic hybridization (aCGH). With 3.5 million reads, SSP detected 56 of 78 (71.8%) subchromosomal abnormalities detected by aCGH. With increased sequencing depth up to 10 million reads and restriction of the size of abnormalities to more than 1 Mb, sensitivity improved to 69 of 73 (94.5%). Of 55 false-positive samples, 35 were caused by deletions/duplications present in maternal DNA, indicating the necessity of a validation test to exclude maternal karyotype abnormalities. This study shows that detection of fetal subchromosomal abnormalities is a viable extension of NIPT based on SSP. Although we focused on the application of cell-free DNA sequencing for NIPT, we believe that this method has broader applications for genetic diagnosis, such as analysis of circulating tumor DNA for detection of cancer.


Assuntos
Aberrações Cromossômicas/embriologia , DNA/sangue , Feto/anormalidades , Diagnóstico Pré-Natal/métodos , Semicondutores , Análise de Sequência de DNA/métodos , Sistema Livre de Células , Deleção Cromossômica , Duplicação Cromossômica , Hibridização Genômica Comparativa , Feminino , Humanos , Peso Molecular , Gravidez
7.
J Am Soc Nephrol ; 27(1): 159-70, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26015452

RESUMO

Macrophages are a heterogeneous cell type implicated in injury, repair, and fibrosis after AKI, but the macrophage population associated with each phase is unclear. In this study, we used a renal bilateral ischemia-reperfusion injury mouse model to identify unique monocyte/macrophage populations by differential expression of Ly6C in CD11b(+) cells and to define the function of these cells in the pathophysiology of disease on the basis of microarray gene signatures and reduction strategies. Macrophage populations were isolated from kidney homogenates by fluorescence-activated cell sorting for whole genome microarray analysis. The CD11b(+)/Ly6C(high) population associated with the onset of renal injury and increase in proinflammatory cytokines, whereas the CD11b(+)/Ly6C(intermediate) population peaked during kidney repair. The CD11b(+)/Ly6C(low) population emerged with developing renal fibrosis. Principal component and hierarchical cluster analyses identified gene signatures unique to each population. The CD11b(+)/Ly6C(intermediate) population had a distinct phenotype of wound healing, confirmed by results of studies inhibiting the macrophage colony-stimulating factor 1 receptor,whereas the CD11b(+)/Ly6C(low) population had a profibrotic phenotype. All populations, including the CD11b(+)/Ly6C(high) population, carried differential inflammatory signatures. The expression of M2-specific markers was detected in both the CD11b(+)/Ly6C(intermediate) and CD11b(+)/Ly6C(low) populations, suggesting these in vivo populations do not fit into the traditional classifications defined by in vitro systems. Results of this study in a renal ischemia-reperfusion injury model allow phenotype and function to be assigned to CD11b(+)/Ly6C(+) monocyte/macrophage populations in the pathophysiology of disease after AKI.


Assuntos
Antígenos Ly/biossíntese , Rim/metabolismo , Macrófagos/classificação , Traumatismo por Reperfusão/metabolismo , Animais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fenótipo , Traumatismo por Reperfusão/sangue
8.
J Nutr ; 145(7): 1636S-1680S, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26451605

RESUMO

The Biomarkers of Nutrition for Development (BOND) project is designed to provide evidence-based advice to anyone with an interest in the role of nutrition in health. Specifically, the BOND program provides state-of-the-art information and service with regard to selection, use, and interpretation of biomarkers of nutrient exposure, status, function, and effect. To accomplish this objective, expert panels are recruited to evaluate the literature and to draft comprehensive reports on the current state of the art with regard to specific nutrient biology and available biomarkers for assessing nutrients in body tissues at the individual and population level. Phase I of the BOND project includes the evaluation of biomarkers for 6 nutrients: iodine, iron, zinc, folate, vitamin A, and vitamin B-12. This review represents the second in the series of reviews and covers all relevant aspects of folate biology and biomarkers. The article is organized to provide the reader with a full appreciation of folate's history as a public health issue, its biology, and an overview of available biomarkers (serum folate, RBC folate, and plasma homocysteine concentrations) and their interpretation across a range of clinical and population-based uses. The article also includes a list of priority research needs for advancing the area of folate biomarkers related to nutritional health status and development.


Assuntos
Biomarcadores/sangue , Ácido Fólico/sangue , Suplementos Nutricionais , Ácido Fólico/administração & dosagem , Humanos , Iodo/sangue , Ferro/sangue , Avaliação Nutricional , Estado Nutricional , Recomendações Nutricionais , Vitamina A/sangue , Vitamina B 12/sangue , Zinco/sangue
9.
Br J Nutr ; 113(12): 1965-77, 2015 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-25917925

RESUMO

Serum and erythrocyte (RBC) total folate are indicators of folate status. No nationally representative population data exist for folate forms. We measured the serum folate forms (5-methyltetrahydrofolate (5-methylTHF), unmetabolised folic acid (UMFA), non-methyl folate (sum of tetrahydrofolate (THF), 5-formyltetrahydrofolate (5-formylTHF), 5,10-methenyltetrahydrofolate (5,10-methenylTHF)) and MeFox (5-methylTHF oxidation product)) by HPLC-MS/MS and RBC total folate by microbiologic assay in US population ≥ 1 year (n approximately 7500) participating in the National Health and Nutrition Examination Survey 2011-2. Data analysis for serum total folate was conducted including and excluding MeFox. Concentrations (geometric mean; detection rate) of 5-methylTHF (37·5 nmol/l; 100 %), UMFA (1·21 nmol/l; 99·9 %), MeFox (1·53 nmol/l; 98·8 %), and THF (1·01 nmol/l; 85·2 %) were mostly detectable. 5-FormylTHF (3·6 %) and 5,10-methenylTHF (4·4 %) were rarely detected. The biggest contributor to serum total folate was 5-methylTHF (86·7 %); UMFA (4·0 %), non-methyl folate (4·7 %) and MeFox (4·5 %) contributed smaller amounts. Age was positively related to MeFox, but showed a U-shaped pattern for other folates. We generally noted sex and race/ethnic biomarker differences and weak (Spearman's r< 0·4) but significant (P< 0·05) correlations with physiological and lifestyle variables. Fasting, kidney function, smoking and alcohol intake showed negative associations. BMI and body surface area showed positive associations with MeFox but negative associations with other folates. All biomarkers showed significantly higher concentrations with recent folic acid-containing dietary supplement use. These first-time population data for serum folate forms generally show similar associations with demographic, physiological and lifestyle variables as serum total folate. Patterns observed for MeFox may suggest altered folate metabolism dependent on biological characteristics.


Assuntos
Ácido Fólico/sangue , Inquéritos Nutricionais , Estado Nutricional , Adolescente , Adulto , Biomarcadores/sangue , Índice de Massa Corporal , Criança , Pré-Escolar , Cromatografia Líquida de Alta Pressão , Eritrócitos/química , Etnicidade , Feminino , Humanos , Lactente , Leucovorina/sangue , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Valores de Referência , Fatores Sexuais , Espectrometria de Massas em Tandem , Tetra-Hidrofolatos/sangue , Estados Unidos/epidemiologia , Adulto Jovem
10.
Anal Bioanal Chem ; 407(11): 2955-64, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25258283

RESUMO

Methylmalonic acid (MMA), a functional indicator of vitamin B12 insufficiency, was measured in the US population in the National Health and Nutrition Examination Survey (NHANES) from 1999 to 2004 using a GC/MS procedure that required 275 µL of sample and had a low throughput (36 samples/run). Our objective was to introduce a more efficient yet highly accurate LC-MS/MS method for NHANES 2011-2014. We adapted the sample preparation with some modifications from a published isotope-dilution LC-MS/MS procedure. The procedure utilized liquid-liquid extraction and generation of MMA dibutyl ester. Reversed-phase chromatography with isocratic elution allowed baseline resolution of MMA from its naturally occurring structural isomer succinic acid within 4.5 min. Our new method afforded an increased throughput (≤160 samples/run) and measured serum MMA with high sensitivity (LOD = 22.1 nmol/L) in only 75 µL of sample. Mean (±SD) recovery of MMA spiked into serum (2 d, 4 levels, 2 replicates each) was 94 % ± 5.5 %. Total imprecision (41 d, 2 replicates each) for three serum quality control pools was 4.9 %-7.9 % (97.1-548 nmol/L). The LC-MS/MS method showed excellent correlation (n = 326, r = 0.99) and no bias (Deming regression, Bland-Altman analysis) compared to the previous GC/MS method. Both methods produced virtually identical mean (±SD) MMA concentrations [LC-MS/MS: 18.47 ± 0.71 ng/mL (n = 17), GC/MS: 18.18 ± 0.67 ng/mL (n = 11)] on a future plasma reference material compared with a GC/MS method procedure from the National Institute of Standards and Technology [18.41 ± 0.70 ng/mL (n = 15)]. No adjustment will be necessary to compare previous (1999-2004) to future (2011-2014) NHANES MMA data.


Assuntos
Cromatografia Líquida/métodos , Ácido Metilmalônico/sangue , Espectrometria de Massas em Tandem/métodos , Vitamina B 12/análise , Anticoagulantes/sangue , Anticoagulantes/farmacologia , Calibragem , Cromatografia Líquida/normas , Cromatografia de Fase Reversa/métodos , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Extração Líquido-Líquido , Inquéritos Nutricionais , Controle de Qualidade , Padrões de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Ácido Succínico/sangue , Espectrometria de Massas em Tandem/normas
11.
Matern Child Health J ; 19(10): 2272-85, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26002178

RESUMO

INTRODUCTION: Information on folate and vitamin B12 deficiency rates in Guatemala is essential to evaluate the current fortification program. The objectives of this study were to describe the prevalence of folate and vitamin B12 deficiencies among women of childbearing age (WCBA) in Guatemala and to identify vulnerable populations at greater risk for nutrient deficiency. METHODS: A multistage cluster probability study was designed with national and regional representation of nonpregnant WCBA (15-49 years of age). Primary data collection was carried out in 2009-2010. Demographic and health information was collected through face-to-face interviews. Blood samples were collected from 1473 WCBA for serum and red blood cell (RBC) folate and serum vitamin B12. Biochemical concentrations were normalized using geometric means. Prevalence rate ratios were estimated to assess relative differences among different socioeconomic and cultural groups including ethnicity, age, education level, wealth index and rural versus urban locality. RESULTS: National prevalence estimates for deficient serum [<10 nmol per liter (nmol/L)] and RBC folate (<340 nmol/L) concentrations were 5.1 % (95 % CI 3.8, 6.4) and 8.9 % (95 % CI 6.7, 11.7), respectively; for vitamin B12 deficiency (<148 pmol/L) 18.5 % (95 % CI 15.6, 21.3). Serum and RBC folate deficiency prevalences were higher for rural areas than for urban areas (8.0 vs. 2.0 % and 13.5 vs. 3.9 %, respectively). The prevalence of RBC folate deficiency showed wide variation by geographic region (3.2-24.9 %) and by wealth index (4.1-15.1 %). The prevalence of vitamin B12 deficiency also varied among regions (12.3-26.1 %). CONCLUSIONS: In Guatemala, folate deficiency was more prevalent among indigenous rural and urban poor populations. Vitamin B12 deficiency was widespread among WCBA. Our results suggest the ongoing need to monitor existing fortification programs, in particular regarding its reach to vulnerable populations.


Assuntos
Deficiência de Ácido Fólico/epidemiologia , Deficiência de Vitamina B 12/epidemiologia , Populações Vulneráveis/estatística & dados numéricos , Adolescente , Adulto , Estudos Transversais , Feminino , Guatemala/epidemiologia , Humanos , Pessoa de Meia-Idade , População Rural/estatística & dados numéricos , Inquéritos e Questionários , População Urbana/estatística & dados numéricos , Vitamina B 12/sangue
12.
J Immunol ; 189(8): 3947-56, 2012 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-22988034

RESUMO

CD4(+)Foxp3(+) regulatory T cells (Treg) are essential for immune homeostasis and maintenance of self-tolerance. They are produced in the thymus and also generated de novo in the periphery in a TGF-ß-dependent manner. Foxp3(+) Treg are also required to achieve tolerance to transplanted tissues when induced by coreceptor or costimulation blockade. Using TCR-transgenic mice to avoid issues of autoimmune pathology, we show that Foxp3 expression is both necessary and sufficient for tissue tolerance by coreceptor blockade. Moreover, the known need in tolerance induction for TGF-ß signaling to T cells can wholly be explained by its role in induction of Foxp3, as such signaling proved dispensable for the suppressive process. We analyzed the relative contribution of TGF-ß and Foxp3 to the transcriptome of TGF-ß-induced Treg and showed that TGF-ß elicited a large set of downregulated signature genes. The number of genes uniquely modulated due to the influence of Foxp3 alone was surprisingly limited. Retroviral-mediated conditional nuclear expression of Foxp3 proved sufficient to confer transplant-suppressive potency on CD4(+) T cells and was lost once nuclear Foxp3 expression was extinguished. These data support a dual role for TGF-ß and Foxp3 in induced tolerance, in which TGF-ß stimulates Foxp3 expression, for which sustained expression is then associated with acquisition of tolerance.


Assuntos
Fatores de Transcrição Forkhead/biossíntese , Fatores de Transcrição Forkhead/genética , Linfócitos T Reguladores/imunologia , Tolerância ao Transplante , Animais , Linhagem Celular Tumoral , Fatores de Transcrição Forkhead/deficiência , Sobrevivência de Enxerto/genética , Sobrevivência de Enxerto/imunologia , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Camundongos Knockout , Camundongos Transgênicos , Transdução de Sinais/genética , Transdução de Sinais/imunologia , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Linfócitos T Reguladores/metabolismo , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/fisiologia , Tolerância ao Transplante/genética
13.
Birth Defects Res ; 116(3): e2329, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38526193

RESUMO

BACKGROUND: Maternal folate and vitamin B12 deficiency can lead to serious adverse pregnancy outcomes. There are no nationally representative estimates on folate and vitamin B12 status among women of reproductive age (WRA) in Malawi. OBJECTIVE: We assessed folate and vitamin B12 status among nonpregnant WRA in Malawi and predicted the risk of folate-sensitive neural tube defects (NTDs) were they to become pregnant. METHODS: Using data from the cross-sectional, nationally representative 2015-2016 Malawi Micronutrient Survey, we calculated the proportion of folate and vitamin B12 deficiency and insufficiency by demographic characteristics among 778 nonpregnant WRA (15-49 years). We predicted NTD prevalence using red blood cell (RBC) folate distributions and a published Bayesian model of the association between RBC folate and NTD risk. Analyses accounted for complex survey design. RESULTS: Among WRA, 8.5% (95% CI: 6.2, 11.6) and 13.3% (10.0, 17.4) had serum (<7 nmol/L) and RBC folate (<305 nmol/L) deficiency, respectively. The proportion of vitamin B12 deficiency (<148 pmol/L) and insufficiency (≤221 pmol/L) was 11.8% (8.6, 16.0) and 40.6% (34.1, 47.4), respectively. RBC folate insufficiency (<748 nmol/L, defined as the concentration associated with the threshold for elevated NTD risk: >8 cases per 10,000 births) was widespread: 81.4% (75.0, 86.4). The predicted NTD risk nationally was 24.7 cases per 10,000 live births. RBC folate insufficiency and higher predicted NTD risk were more common among WRA living in urban areas or with higher education. CONCLUSIONS: These findings highlight the importance of nutritional and NTD surveillance in Malawi and the opportunity for improving folate and vitamin B12 nutrition among Malawian WRA.


Assuntos
Defeitos do Tubo Neural , Oligoelementos , Gravidez , Feminino , Humanos , Micronutrientes , Ácido Fólico , Vitamina B 12 , Teorema de Bayes , Estudos Transversais , Malaui/epidemiologia , Defeitos do Tubo Neural/epidemiologia , Defeitos do Tubo Neural/etiologia , Nascido Vivo , Vitaminas
14.
Anal Chem ; 85(24): 11732-8, 2013 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-24187941

RESUMO

The National Institute of Standards and Technology (NIST), in collaboration with the National Institutes of Health (NIH), has developed a Standard Reference Material (SRM) to support technology development in metabolomics research. SRM 1950 Metabolites in Human Plasma is intended to have metabolite concentrations that are representative of those found in adult human plasma. The plasma used in the preparation of SRM 1950 was collected from both male and female donors, and donor ethnicity targets were selected based upon the ethnic makeup of the U.S. population. Metabolomics research is diverse in terms of both instrumentation and scientific goals. This SRM was designed to apply broadly to the field, not toward specific applications. Therefore, concentrations of approximately 100 analytes, including amino acids, fatty acids, trace elements, vitamins, hormones, selenoproteins, clinical markers, and perfluorinated compounds (PFCs), were determined. Value assignment measurements were performed by NIST and the Centers for Disease Control and Prevention (CDC). SRM 1950 is the first reference material developed specifically for metabolomics research.


Assuntos
Análise Química do Sangue/normas , Metabolômica/normas , Adulto , Aminoácidos/sangue , Biomarcadores/sangue , Carotenoides/sangue , Ácidos Graxos/sangue , Feminino , Humanos , Masculino , National Institutes of Health (U.S.) , Padrões de Referência , Estados Unidos , Vitaminas/sangue
15.
Am J Clin Nutr ; 117(5): 985-997, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37137617

RESUMO

BACKGROUND: RBC folate concentrations are monitored at the population level, with a recommended threshold for optimal neural tube defect (NTD) prevention. A corresponding threshold for serum folate has not been established. OBJECTIVES: This study aimed to estimate the serum folate insufficiency threshold corresponding to the RBC folate threshold for NTD prevention and examine how this threshold is modified by vitamin B12 status. METHODS: Participants were women (15-40 y; not pregnant or lactating; n = 977) from a population-based biomarker survey in Southern India. RBC folate and serum folate were measured via microbiologic assay. RBC folate deficiency (<305 nmol/L) and insufficiency (<748 nmol/L), serum vitamin B12 deficiency (<148 pmol/L) and vitamin B12 insufficiency (<221 pmol/L), elevated plasma MMA (>0.26 µmol/L), elevated plasma homocysteine (>10.0 µmol/L), and elevated HbA1c (≥6.5%) were evaluated. Bayesian linear models were used to estimate unadjusted and adjusted thresholds. RESULTS: Compared with adequate vitamin B12 status, the estimated serum folate threshold was higher in participants with serum vitamin B12 deficiency (72.5 vs. 28.1 nmol/L) or vitamin B12 insufficiency (48.7 vs. 24.3 nmol/L) and elevated MMA (55.6 vs. 25.9 nmol/L). The threshold was lower in participants with elevated HbA1c (HbA1c ≥6.5% vs. <6.5%; 21.0 vs. 40.5 nmol/L). CONCLUSIONS: The estimated serum folate threshold for optimal NTD prevention was similar to previous reports (24.3 vs. 25.6 nmol/L) among participants with sufficient vitamin B12 status. However, this threshold was more than 2-fold higher in participants with vitamin B12 deficiency and substantially higher across all indicators of insufficient vitamin B12 status (<221 pmol/L, elevated MMA, combined B12, impaired vitamin B12 status), and lower in participants with elevated HbA1c. Findings suggest a serum folate threshold for NTD prevention may be possible in some settings; however, it may not be appropriate in populations with high prevalence of vitamin B12 insufficiency. Am J Clin Nutr 2023;xx:xx-xx. This trial was registered at https://clinicaltrials.gov as NCT04048330.


Assuntos
Defeitos do Tubo Neural , Deficiência de Vitamina B 12 , Humanos , Feminino , Gravidez , Masculino , Ácido Fólico , Teorema de Bayes , Hemoglobinas Glicadas , Lactação , Defeitos do Tubo Neural/epidemiologia , Defeitos do Tubo Neural/prevenção & controle , Vitamina B 12 , Deficiência de Vitamina B 12/epidemiologia , Biomarcadores , Eritrócitos , Vitaminas , Homocisteína
16.
Front Nutr ; 10: 1201007, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37680900

RESUMO

Introduction: Excessive alcohol consumption leads to a myriad of detrimental health effects, including alcohol-associated liver disease (ALD). Unfortunately, no available treatments exist to combat the progression of ALD beyond corticosteroid administration and/or liver transplants. Dihydromyricetin (DHM) is a bioactive polyphenol and flavonoid that has traditionally been used in Chinese herbal medicine for its robust antioxidant and anti-inflammatory properties. It is derived from many plants, including Hovenia dulcis and is found as the active ingredient in a variety of popular hangover remedies. Investigations utilizing DHM have demonstrated its ability to alleviate ethanol-induced disruptions in mitochondrial and lipid metabolism, while demonstrating hepatoprotective activity. Methods: Female c57BL/6J mice (n = 12/group) were treated using the Lieber DeCarli forced-drinking and ethanol (EtOH) containing liquid diet, for 5 weeks. Mice were randomly divided into three groups: (1) No-EtOH, (2) EtOH [5% (v/v)], and (3) EtOH [5% (v/v)] + DHM (6 mg/mL). Mice were exposed to ethanol for 2 weeks to ensure the development of ALD pathology prior to receiving dihydromyricetin supplementation. Statistical analysis included one-way ANOVA along with Bonferroni multiple comparison tests, where p ≤ 0.05 was considered statistically significant. Results: Dihydromyricetin administration significantly improved aminotransferase levels (AST/ALT) and reduced levels of circulating lipids including LDL/VLDL, total cholesterol (free cholesterol), and triglycerides. DHM demonstrated enhanced lipid clearance by way of increased lipophagy activity, shown as the increased interaction and colocalization of p62/SQSTM-1, LC3B, and PLIN-1 proteins. DHM-fed mice had increased hepatocyte-to-hepatocyte lipid droplet (LD) heterogeneity, suggesting increased neutralization and sequestration of free lipids into LDs. DHM administration significantly reduced prominent pro-inflammatory cytokines commonly associated with ALD pathology such as TNF-α, IL-6, and IL-17. Discussion: Dihydromyricetin is commercially available as a dietary supplement. The results of this proof-of-concept study demonstrate its potential utility and functionality as a cost-effective and safe candidate to combat inflammation and the progression of ALD pathology.

17.
Nat Neurosci ; 26(1): 12-26, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36536241

RESUMO

Iron dysregulation has been implicated in multiple neurodegenerative diseases, including Parkinson's disease (PD). Iron-loaded microglia are frequently found in affected brain regions, but how iron accumulation influences microglia physiology and contributes to neurodegeneration is poorly understood. Here we show that human induced pluripotent stem cell-derived microglia grown in a tri-culture system are highly responsive to iron and susceptible to ferroptosis, an iron-dependent form of cell death. Furthermore, iron overload causes a marked shift in the microglial transcriptional state that overlaps with a transcriptomic signature found in PD postmortem brain microglia. Our data also show that this microglial response contributes to neurodegeneration, as removal of microglia from the tri-culture system substantially delayed iron-induced neurotoxicity. To elucidate the mechanisms regulating iron response in microglia, we performed a genome-wide CRISPR screen and identified novel regulators of ferroptosis, including the vesicle trafficking gene SEC24B. These data suggest a critical role for microglia iron overload and ferroptosis in neurodegeneration.


Assuntos
Ferroptose , Células-Tronco Pluripotentes Induzidas , Sobrecarga de Ferro , Doença de Parkinson , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Ferro/metabolismo , Sobrecarga de Ferro/metabolismo , Microglia/metabolismo , Doença de Parkinson/genética
18.
Curr Dev Nutr ; 7(3): 100052, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37181934

RESUMO

Background: Women of reproductive age are at an increased risk of anemia and micronutrient deficiencies. Evidence supports the role of periconceptional nutrition in the development of neural tube defects (NTDs) and other pregnancy complications. Vitamin B12 deficiency is a risk factor for NTDs and may modify folate biomarkers that predict NTD risk at the population level. There is an interest in mandatory fortification with vitamin B12 and folic acid for anemia and birth defect prevention. However, there are limited population-representative data needed to inform policy and guidelines. Objectives: This randomized trial will be conducted to evaluate the efficacy of quadruple-fortified salt (QFS; iron, iodine, folic acid, vitamin B12) in 1,000 households in Southern India. Methods: Women 18 to 49 y who are not pregnant or lactating and reside within the catchment area of our community-based research site in Southern India will be screened and invited to participate in the trial. After informed consent, women and their households will be randomized to receive one of the following 4 interventions: 1) double-fortified salt (DFS; iron, iodine), 2) DFS + folic acid (iron, iodine, folic acid), 3) DFS + vitamin B12 (iron, iodine, vitamin B12), or 4) DFS + folic acid and vitamin B12 (QFS; iron, iodine, folic acid, vitamin B12) for 12 mo. Structured interviews will be conducted by trained nurse enumerators to collect sociodemographic, anthropometric, dietary, health, and reproductive history data. Biological samples will be collected at baseline, midpoint, and endpoint. Whole blood will be analyzed for hemoglobin using Coulter Counter. Total vitamin B12 will be measured by chemiluminescence; red blood cell folate and serum folate will be evaluated using the World Health Organization-recommended microbiologic assay. Conclusions: The results of this randomized trial will help to evaluate the efficacy of QFS to prevent anemia and micronutrient deficiencies. Clinical trial registration numbers: NCT03853304 and Clinical Trial Registry of India REF/2019/03/024479. Registration number: NCT03853304 and REF/2019/03/024479.

19.
J Nutr ; 142(5): 894-900, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22437557

RESUMO

The NHANES measured serum and RBC folate concentrations by using a radioassay during prefortification (1988-1994) and postfortification (1999-2006) periods followed by the use of a microbiologic assay (MBA) from 2007-2010. The MBA produces higher concentrations than does the radioassay and is considered to be more accurate. To allow for accurate long-term trending (1988-2010), we evaluated different regression models (linear, piecewise linear, and fractional polynomial) to assay-adjust the radioassay results to be comparable to the MBA results. The data used to derive the regression models originated from 2 crossover studies in which the 2 assays were applied to a set of 325 serum and 171 whole-blood samples. Fractional polynomial regression of logarithmically transformed data provided the best fit for serum folate. Linear regression of logarithmically transformed whole-blood data provided an equally good fit compared with the other models and was the simplest to apply for RBC folate. Prefortification serum and RBC folate geometric mean concentrations increased after adjustment from 13.0 to 16.7 nmol/L and from 403 to 747 nmol/L, respectively. Postfortification serum folate concentrations increased from ~30 to ~43 nmol/L, and RBC folate concentrations increased from ~600 to ~1100 nmol/L after adjustment, with some variation across survey cycles. The presented regression equations allow the estimation of more accurate prevalence estimates and long-term trends in blood folate concentrations in the U.S. population by using results that are equivalent to the MBA. This information will be useful to public health officials in the United States who are dealing with folic acid fortification issues.


Assuntos
Eritrócitos/metabolismo , Deficiência de Ácido Fólico , Ácido Fólico/sangue , Técnicas Microbiológicas/métodos , Inquéritos Nutricionais/métodos , Ensaio Radioligante/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Ácido Fólico/análise , Deficiência de Ácido Fólico/sangue , Deficiência de Ácido Fólico/diagnóstico , Deficiência de Ácido Fólico/epidemiologia , Humanos , Masculino , Técnicas Microbiológicas/normas , Técnicas Microbiológicas/estatística & dados numéricos , Pessoa de Meia-Idade , Inquéritos Nutricionais/normas , Inquéritos Nutricionais/estatística & dados numéricos , Prevalência , Ensaio Radioligante/normas , Ensaio Radioligante/estatística & dados numéricos , Estados Unidos/epidemiologia , Adulto Jovem
20.
J Nutr ; 142(5): 886-93, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22437563

RESUMO

The NHANES has monitored folate status of the U.S. population from prefortification (1988-1994) to postfortification (1999-2010) by measuring serum and RBC folate concentrations. The Bio-Rad radioassay (BR) was used from 1988 to 2006, and the microbiologic assay (MBA) was used from 2007 to 2010. The MBA produces higher concentrations than the BR and is considered to be more accurate. Thus, to bridge assay differences and to examine folate trends over time, we adjusted the BR results to be comparable to the MBA results. Postfortification, assay-adjusted serum and RBC folate concentrations were 2.5 times and 1.5 times prefortification concentrations, respectively, and showed a significant linear trend (P < 0.001) to slightly lower concentrations during 1999-2010. The postfortification prevalence of low serum (<10 nmol/L) or RBC (<340 nmol/L) folate concentrations was ≤ 1%, regardless of demographic subgroup, compared with 24% for serum folate and 3.5% for RBC folate prefortification, with substantial variation among demographic subgroups. The central 95% reference intervals for serum and RBC folate varied by demographic subgroup during both pre- and postfortification periods. Age and dietary supplement use had the greatest effects on prevalence estimates of low folate concentrations during the prefortification period. In summary, the MBA-equivalent blood folate concentrations in the U.S. population showed first a sharp increase from pre- to postfortification, then showed a slight decrease (17% for serum and 12% for RBC folate) during the 12-y postfortification period. The MBA-equivalent pre- and postfortification reference concentrations will inform countries that plan folic acid fortification or that need to evaluate its impact.


Assuntos
Eritrócitos/metabolismo , Deficiência de Ácido Fólico , Ácido Fólico/administração & dosagem , Ácido Fólico/sangue , Alimentos Fortificados/estatística & dados numéricos , Inquéritos Nutricionais/estatística & dados numéricos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Deficiência de Ácido Fólico/sangue , Deficiência de Ácido Fólico/epidemiologia , Deficiência de Ácido Fólico/prevenção & controle , Humanos , Masculino , Pessoa de Meia-Idade , Morbidade/tendências , Prevalência , Estados Unidos/epidemiologia , Adulto Jovem
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