RESUMEN

INTRODUCTION: DNA hypomethylation in patients with systemic lupus erythematosus (SLE) has been recently documented in the literature. Low levels of DNA methylation have been observed globally and in genes associated with immune and inflammatory pathways in SLE's CD4+T lymphocytes. Given that certain micronutrients can either donate methyl groups within one-carbon metabolism pathways or serve as cofactors for enzymes involved in the DNA methylation process, this randomised, double-blind, placebo-controlled trial aims to investigate whether a 3-month supplementation of folic acid and vitamin B12 will modulate the DNA methylation profile in subcutaneous adipose tissue (primary outcome) of women with SLE and normal weight or excess body weight. As secondary objectives, we will assess gene expression, telomere length and phenotypic characteristics (ie, clinical parameters, body weight and composition, abdominal circumference, food intake and disordered eating attitude, physical activity, lipid profile, serum concentrations of leptin, adiponectin, and cytokines). METHODS AND ANALYSIS: Patients will be classified according to their nutritional status by body mass index in normal weight or excess body weight. Subsequently, patients in each group will be randomly assigned to either a placebo or an intervention group (folic acid (400 mcg) and vitamin B12 (2000 mcg) supplementation). Endpoint evaluations will be conducted using both intention-to-treat and per-protocol analyses. This study has the potential to design new personalised nutritional approaches as adjunctive therapy for patients with SLE. ETHICS AND DISSEMINATION: This study has been reviewed and approved by the Ethical Committee from Clinical Hospital of the School of Medicine of the University of Sao Paulo, Brazil (CAAE.: 47317521.8.0000.0068). TRIAL REGISTRATION NUMBER: NCT05097365 (first version).

Asunto(s)

Metilación de ADN , Suplementos Dietéticos , Ácido Fólico , Lupus Eritematoso Sistémico , Estado Nutricional , Vitamina B 12 , Humanos , Lupus Eritematoso Sistémico/complicaciones , Lupus Eritematoso Sistémico/tratamiento farmacológico , Femenino , Método Doble Ciego , Vitamina B 12/uso terapéutico , Ácido Fólico/uso terapéutico , Ácido Fólico/sangre , Adulto , Persona de Mediana Edad , Ensayos Clínicos Controlados Aleatorios como Asunto , Adulto Joven , Índice de Masa Corporal

RESUMEN

Folate metabolism is required for important biochemical processes that regulate cell functioning, but its role in female reproductive physiology in cattle during peri- and post-conceptional periods has not been thoroughly explored. Previous studies have shown the presence of folate in bovine oviductal fluid, as well as finely regulated gene expression of folate receptors and transporters in bovine oviduct epithelial cells (BOECs). Additionally, extracellular folic acid (FA) affects the transcriptional levels of genes important for the functioning of BOECs. However, it remains unknown whether the anatomical and cyclic features inherent to the oviduct affect regulation of folate metabolism. The present study aimed to characterize the gene expression pattern of folate cycle enzymes in BOECs from different anatomical regions during the estrous cycle and to determine the transcriptional response of these genes to increasing concentrations of exogenous FA. A first PCR screening showed the presence of transcripts encoding dihydrofolate reductase (DHFR), methylenetetrahydrofolate reductase (MTHFR), and methionine synthase (MTR) in bovine reproductive tissues (ovary, oviduct and uterus), with expression levels in oviductal tissues comparable to, or even higher than, those detected in ovarian and uterine tissues. Moreover, expression analysis through RT-qPCR in BOECs from the ampulla and isthmus during different stages of the estrous cycle demonstrated that folate metabolism-related enzymes exhibited cycle-dependent variations. In both anatomical regions, DHFR was upregulated during the preovulatory stage, while MTHFR and MTR exhibited increased expression levels during the postovulatory stage. Under in vitro culture conditions, ampullary and isthmic cells were cultured in the presence of 10, 50, and 100 µM FA for 24 h. Under these conditions, isthmus epithelial cells exhibited a unique transcriptional response to exogenous FA, showing a pronounced increase in MTR expression levels. Our results suggest that the expression of folate metabolism-related genes in BOECs is differentially regulated during the estrous cycle and may respond to exogenous levels of folate. This offers a new perspective on the transcriptional regulation of genes associated with the folate cycle in oviductal cells and provides groundwork for future studies on their functional and epigenetic implications within the oviductal microenvironment.

Asunto(s)

Ciclo Estral , Ácido Fólico , Animales , Femenino , Bovinos , Ciclo Estral/metabolismo , Ácido Fólico/farmacología , Ácido Fólico/metabolismo , Trompas Uterinas/metabolismo , Trompas Uterinas/efectos de los fármacos , Oviductos/metabolismo , Oviductos/efectos de los fármacos , Tetrahidrofolato Deshidrogenasa/genética , Tetrahidrofolato Deshidrogenasa/metabolismo , Células Epiteliales/metabolismo , Células Epiteliales/efectos de los fármacos , Metilenotetrahidrofolato Reductasa (NADPH2)/genética , Metilenotetrahidrofolato Reductasa (NADPH2)/metabolismo , 5-Metiltetrahidrofolato-Homocisteína S-Metiltransferasa/metabolismo , 5-Metiltetrahidrofolato-Homocisteína S-Metiltransferasa/genética , Regulación de la Expresión Génica/efectos de los fármacos , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos

RESUMEN

Global concerns over folate deficiency, the risks of excessive synthetic folic acid consumption, and food loss implications for environmental sustainability and food security drive needs of innovative approaches that align food by-product valorisation with folate bio-enrichment. This study explored the use of three fruit by-products extracts (grape, passion fruit, and pitaya) and whey to develop a folate bio-enriched fermented whey-based beverage. Three strains (Lacticaseibacillus rhamnosus LGG, Bifidobacterium infantis BB-02, and Streptococcus thermophilus TH-4) were tested for folate production in different fermentation conditions in modified MRS medium and in a whey-based matrix prepared with water extracts of these fruit by-products. B. infantis BB-02 and S. thermophilus TH-4, alone and in co-culture, were the best folate producers. The selection of cultivation conditions, including the presence of different substrates and pH, with grape by-product water extract demonstrating the most substantial effect on folate production among the tested extracts, was crucial for successfully producing a biofortified fermented whey-based beverage (FWBB). The resulting FWBB provided 40.7 µg of folate per 100 mL after 24 h of fermentation at 37 °C, effectively leveraging food by-products. Moreover, the beverage showed no cytotoxicity in mouse fibroblast cells tests. This study highlights the potential for valorising fruit by-products and whey for the design of novel bioenriched foods, promoting health benefits and contributing to reduced environmental impact from improper disposal.

Asunto(s)

Fermentación , Ácido Fólico , Frutas , Suero Lácteo , Animales , Frutas/química , Ratones , Humanos , Suero Lácteo/química , Bebidas/microbiología , Streptococcus thermophilus/metabolismo , Streptococcus thermophilus/crecimiento & desarrollo , Lacticaseibacillus rhamnosus/metabolismo , Lacticaseibacillus rhamnosus/crecimiento & desarrollo , Bifidobacterium/metabolismo , Bifidobacterium/crecimiento & desarrollo , Vitis/química

RESUMEN

BACKGROUND: Some studies have reported that homocysteine, vitamin B12, and folic acid levels are associated with polycystic ovary syndrome (PCOS), whereas other studies yielded controversial results. OBJECTIVES: This study aimed to systematize the available evidence of homocysteine, vitamin B12, and folate levels in women with and without PCOS. DESIGN: Systematic review and meta-analysis. DATA SOURCES AND METHODS: A systematic search without language restrictions was performed on PubMed, Ovid/Medline, Scopus, Embase, and Web of Science. In addition, the reference lists of the selected studies were reviewed. The Newcastle-Ottawa Scale was employed to evaluate the quality of studies. The means and standard deviations of the outcomes were pooled as standardized mean differences (SMDs) with 95% confidence intervals (CI). Furthermore, the DerSimonian and Laird method was employed for the quantitative synthesis. RESULTS: A total of 75 studies met the eligibility criteria for at least one outcome. Patients with PCOS had higher circulating homocysteine levels than those without (SMD: 0.82; 95% CI: 0.62-1.02, n = 70 studies, p < 0.001). This trend remained in the sensitivity and subgroup analyses by world regions of studies, assay methods, and insulin resistance. No significant differences were observed in circulating vitamin B12 (SMD: -0.11; 95% CI: -0.25 to 0.03; n = 17 studies, p = 0.13) and folate levels (SMD: -0.2; 95% CI: -0.68 to 0.27; n = 17 studies, p = 0.41) between patients with and without PCOS. CONCLUSIONS: (i) Patients with PCOS exhibited significantly higher homocysteine levels than those without, and (ii) no significant differences were observed in both vitamin B12 and folate levels in women with and without PCOS. REGISTRATION: PROSPERO ID (CRD42023432883).

Asunto(s)

Ácido Fólico , Homocisteína , Síndrome del Ovario Poliquístico , Vitamina B 12 , Humanos , Síndrome del Ovario Poliquístico/sangre , Ácido Fólico/sangre , Femenino , Vitamina B 12/sangre , Homocisteína/sangre

RESUMEN

BACKGROUND: Interactions between genetic and environmental variables contribute to the autoimmune inflammatory process in multiple sclerosis (MS). Elevated homocysteine levels, and vitamin D, vitamin B12, and folate deficiencies are some of the environmental factors associated with the pathogenesis of MS. Considering that the relationship between MTHFR 677C>T (rs1801133) genetic variant, homocysteine, and folate in patients with MS remains unclear and that their role were not extensively explored in the clinical course of the disease, we investigated whether this variant and plasma homocysteine and folate levels are associated with MS susceptibility, disability, disability progression, and inflammatory biomarkers. METHODS: The case-control study included 163 patients with MS categorized using the Expanded Disability Status Scale (EDSS) as mild (EDSS<3) and moderate/high (EDSS≥3) disability, and 226 healthy controls (HC). Disability progression was evaluated using Multiple Sclerosis Severity Score (MSSS) and the MTHFR 677C>T variant was genotyped using real time polymerase chain reaction. The plasma levels of some inflammatory biomarkers were determined. Two new composed scores were proposed: the first, namely as inflammatory activity index (IAI), was entered as a latent vector extracted from the macrophage M1 + T helper (Th)1 + Th17 + Th2 + T regulatory (Treg) cytokines, + tumor necrosis factor (TNF)-α+ soluble TNF receptor (sTNFR)-1 + sTNFR2. The second score, namely MS-severity index was entered as a latent vector extracted from the EDSS + MSSS scores + MS diagnosis. RESULTS: Patients with MS showed higher homocysteine and folate than controls (p < 0.001); homocysteine, and the M1, Th1, Th17, and Th2 Treg cytokine values were different between the three study groups and increased from HC to MS patients with mild disability and to MS patients with moderate/high disability (p < 0.0001). The levels of TNF-α and their soluble receptors sTNFR1 and sTNFR2 were higher in MS patients with EDSS≥3 than in the two other groups (EDSS<3 and HC) (p < 0.001). There was no association between the MTHFR 677 C > T genotypes and MS susceptibility, disability and disability progression (p > 0.05). Moreover, 21.8 % of the disability variance was explained by age, IAI and C-reactive protein (CRP) (all positively associated); 10.9 % of the disability progression variance was predicted by IAI and CRP (both positively) and 25-hydroxyvitamin D (negatively), whereas 54.4 % of the severity index (MS-EDSS-MSSS) was explained by the regression on age, IAI, homocysteine, folate, and CRP (all positively), and adiponectin, body mass index, and 25-hydroxyvitamin D (all negatively), female sex, and the MTHFR 677 TT genotype. In patients and controls, 16.6 % of the variance in the homocysteine was explained by the MTHFR 677 TT genotype and age (both positively), folate (negatively) and male sex. CONCLUSION: The MTHFR 677C>T variant has an indirect effect on the increase in disability in patients with MS, which also depends on factors such as age, sex, ad folate status.

Asunto(s)

Progresión de la Enfermedad , Predisposición Genética a la Enfermedad , Homocisteína , Metilenotetrahidrofolato Reductasa (NADPH2) , Esclerosis Múltiple , Humanos , Metilenotetrahidrofolato Reductasa (NADPH2)/genética , Femenino , Masculino , Adulto , Homocisteína/sangre , Estudios de Casos y Controles , Esclerosis Múltiple/genética , Esclerosis Múltiple/sangre , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Ácido Fólico/sangre , Índice de Severidad de la Enfermedad

RESUMEN

Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer that is mainly treated with cytotoxic chemotherapy. However, this treatment is not always effective, and an important percentage of patients develop recurrence. Nanomaterials are emerging as alternative treatment options for various diseases, including cancer. This work reports the synthesis, characterization, antitumor activity evaluation, and sub-acute toxicity studies of two formulations based on amorphous silica nanoparticles (SiNPs). They are functionalized with 3-aminopropyltriethoxisilane (Si@NH2) and folic acid (FA; Si@FA). The results show that SiNPs reduce the viability and migration of TNBC MDA-MB-231 and 4T1 cell lines and Si@FA do not affect the growth of the mammary nonmalignant HC11 cells. In addition, Si@FA induces reactive oxygen species (ROS) generation and displays antiproliferative and subsequently proapoptotic effects in MDA-MB-231 cells. Moreover, none of the SiNPs cause signs of sub-acute toxicity in mice when administered at 30 mg/kg over a month. In conclusion, these nanosystems display intrinsic antitumor activity without causing toxic in vivo effects, being a promising therapeutic alternative for TNBC.

Asunto(s)

Antineoplásicos , Apoptosis , Proliferación Celular , Supervivencia Celular , Ácido Fólico , Nanopartículas , Especies Reactivas de Oxígeno , Dióxido de Silicio , Neoplasias de la Mama Triple Negativas , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Neoplasias de la Mama Triple Negativas/patología , Dióxido de Silicio/química , Nanopartículas/química , Humanos , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/síntesis química , Animales , Femenino , Ratones , Especies Reactivas de Oxígeno/metabolismo , Proliferación Celular/efectos de los fármacos , Apoptosis/efectos de los fármacos , Ácido Fólico/química , Ácido Fólico/farmacología , Supervivencia Celular/efectos de los fármacos , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Ratones Endogámicos BALB C , Silanos/química , Silanos/farmacología , Propilaminas/química , Propilaminas/farmacología , Propilaminas/síntesis química , Relación Dosis-Respuesta a Droga

RESUMEN

BACKGROUND: Folic acid (FA), a synthetically produced compound analogous to vitamin B9, also referred to as vitamin folate, is an essential compound in human health and faces challenges in stability during food processing. This study explores the incorporation of FA into carboxymethylcellulose (CMC) nanofibers using electrospinning to enhance its stability. RESULTS: In this study, optimization of both electrospinning and solution parameters facilitated the fabrication of nanofibers. Furthermore, incorporating FA into CMC/polyethylene oxide (PEO) nanofibers resulted in thinner fibers, with an average diameter of 88 nm, characterized by a flat shape and smooth surface. Fourier transform infrared spectroscopic analysis demonstrated substantial hydrogen bonding interactions between FA and the polar groups present in CMC. This interaction contributed to an encapsulation efficiency of 94.5%, with a yield exceeding 87%. Thermal analysis highlighted mutual interference between CMC and PEO, with FA enhancing the thermal stability and reducing the melting temperatures and enthalpies of PEO, while also increasing the reaction heats of CMC. The encapsulated FA remained stable in acidic conditions, with only 6% degradation over 30 days, demonstrating the efficacy of CMC/PEO nanofibers in safeguarding FA against acidic environments. Moreover, the nanofibers provided a protective barrier against UV radiation, thereby preserving the stability of FA. CONCLUSION: This study emphasizes the efficacy of CMC/PEO nanofibers as a protective matrix against FA degradation. The findings indicate that this innovative approach could significantly diversify the applications of FA in food fortification, addressing concerns regarding its vulnerability to temperature and hydrolysis reactions during food processing. © 2024 Society of Chemical Industry.

Asunto(s)

Carboximetilcelulosa de Sodio , Ácido Fólico , Nanofibras , Polietilenglicoles , Nanofibras/química , Ácido Fólico/química , Carboximetilcelulosa de Sodio/química , Polietilenglicoles/química , Estabilidad de Medicamentos , Liberación de Fármacos , Portadores de Fármacos/química , Composición de Medicamentos/métodos

RESUMEN

Background and Objectives: It is not clear whether the increase in nutrition students' knowledge is associated with healthier eating behavior and fewer micronutrient deficiencies that can cause DNA damage. Deficiency in some vitamins can be a risk factor for increased homocysteine (Hcy) levels, a marker of cardiovascular risk. Therefore, this study aimed to verify whether dietary and serum folate and vitamin B12 are associated with Hcy levels and DNA damage in female university students. Methods: A cross-sectional study was conducted with female university students from southern Brazil. Folate, vitamin B12, and Hcy levels were determined in their diet or serum. DNA damage levels were assessed by the alkaline comet assay (index and frequency) and the buccal micronucleus assay (micronuclei frequency and binucleated cells frequency). Results: Correlation analyses did not show an association between Hcy levels and dietary or serum folate and vitamin B12 consumption. Dietary folate and vitamin B12 were associated with the index and frequency of damages; however, only serum folate was negatively associated with the index and frequency of damages. Additionally, the frequency of binucleated cells was negatively associated with dietary vitamin B12 and positively associated with serum levels. Serum folate was negatively associated with the frequency of micronuclei. Hcy levels were associated with the index and frequency of damages. Conclusion: These findings strengthen the role of healthier dietary patterns with adequate micronutrients as a preventive strategy to reduce the risk of cardiovascular diseases. This approach should play a pivotal role in shaping health policies and advocating for appropriate food choices.(AU)

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Justificativa e Objetivos: Não está claro se o aumento do conhecimento dos estudantes de nutrição está associado a um comportamento alimentar mais saudável, com menores deficiências de micronutrientes que podem induzir danos no DNA. A deficiência de algumas vitaminas pode ser um fator de risco para o aumento dos níveis de homocisteína (Hcy), um marcador de risco cardiovascular. Portanto, este estudo verificou se folato e vitamina B12 dietético e sérico estão associados aos níveis de Hcy e danos no DNA em estudantes universitárias. Métodos: Estudo transversal com universitárias do sul do Brasil. Determinou-se folato, vitamina B12 e Hcy dietético e séricos. Os níveis de danos no DNA foram avaliados pelo ensaio do cometa alcalino (índice e frequência) e pelo ensaio de micronúcleos bucais (frequência de micronúcleos e células binucleadas). Resultados: Análises de correlação não mostraram associação entre os níveis de Hcy com o consumo de folato e vitamina B12 dietético ou sérico. Folato e vitamina B12 dietéticos associou-se ao índice e frequência de danos, entretanto, somente folato sérico associou-se negativamente ao índice e frequência de danos. Ainda, a frequência de células binucleadas estava negativamente associada à vitamina B12 da dieta e positivamente associada aos níveis séricos. Folato sérico associou-se negativamente à frequência de micronúcleos. Os níveis de Hcy associou-se ao índice e frequência de danos. Conclusão: Esses achados fortalecem o papel de padrões alimentares mais saudáveis com micronutrientes adequados como estratégia preventiva visando a redução do risco de doenças cardiovasculares. Esta abordagem deve desempenhar um papel fundamental na formulação de políticas de saúde e na defesa de escolhas alimentares apropriadas.(AU)

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Justificación y Objetivos: No está claro si el aumento del conocimiento de estudiantes de nutrición está asociado con un comportamiento alimentario más saludable, con menores deficiencias de micronutrientes que puedan inducir daños en ADN. La deficiencia de algunas vitaminas puede ser un factor de riesgo para el aumento de los niveles de homocisteína (Hcy), marcador de riesgo cardiovascular. Consiguiente, este estudio verificó si folato y vitamina B12 dietéticos y séricos están asociados con niveles de Hcy y daños en el ADN en estudiantes universitarias. Métodos: Estudio transversal con universitarias del sur de Brasil. Se determinaron folato, vitamina B12 y Hcy dietéticos y séricos. Los niveles de daño en el ADN se evaluaron por ensayo del cometa alcalino (índice y frecuencia) y el ensayo de micronúcleos bucales (frecuencia de micronúcleos y células binucleadas). Resultados: Los análisis de correlación no mostraron asociación entre los niveles de Hcy con folato y vitamina B12 dietéticos y séricos. Folato y vitamina B12 dietéticos se asociaron con índice y frecuencia de daños, pero, solo folato sérico se asoció negativamente con índice y frecuencia de daños. Además, la frecuencia de células binucleadas estaba negativamente asociada con la vitamina B12 de la dieta y positivamente asociada con los niveles séricos. Folato sérico se asoció negativamente con la frecuencia de micronúcleos. Los niveles de Hcy se asociaron con índice y frecuencia de daños. Conclusión: Estos hallazgos refuerzan el papel de patrones alimentarios más saludables con micronutrientes adecuados como estrategia preventiva para reducir el riesgo de enfermedades cardiovasculares. Este enfoque debería desempeñar un papel fundamental en la elaboración de políticas de salud y en la promoción de elecciones alimenticias apropiadas.(AU)

Asunto(s)

Humanos , Femenino , Vitamina B 12 , Daño del ADN , ADN , Enfermedades Cardiovasculares , Inestabilidad Genómica , Ácido Fólico , Factores de Riesgo de Enfermedad Cardiaca , Homocisteína , Ensayo Cometa

RESUMEN

[ABSTRACT]. Objective. To estimate the national and regional population attributable fraction (PAF) and potential number of preventable anemia cases for three nutritional risk factors (iron, red blood cell folate [RBCF], and vitamin B12 deficiencies) among women of childbearing age in Belize. Methods. A national probability-based household and micronutrient survey capturing sociodemographic and health information was conducted among 937 nonpregnant Belizean women aged 15–49 years. Blood samples were collected to determine hemoglobin, ferritin, alpha-1-glycoprotein (AGP), RBCF, and vitamin B12 status. All analyses used sample weights and design variables to reflect a complex sample survey. Logistic regression was used to determine adjusted prevalence risk (aPR) ratios, which were then used to estimate national and regional PAF for anemia. Results. The overall prevalence of anemia (hemoglobin <12 g/dL) was 21.2% (95% CI [18.7, 25.3]). The prevalence of anemia was significantly greater among women with iron deficiency (59.5%, 95% CI [48.7, 69.5]) compared to women without iron deficiency (15.2%, 95% CI [12.2, 18.3]; aPR 3.9, 95% CI [2.9, 5.1]). The three nutritional deficiencies examined contributed to 34.6% (95% CI [22.1, 47.1]) of the anemia cases. If all these nutritional deficiencies could be eliminated, then an estimated 5 953 (95% CI [3 807, 8 114]) anemia cases could be prevented. Conclusions. This study suggests that among women of child-bearing age in Belize, anemia cases might be reduced by a third if three modifiable nutritional risk factors (iron, RBCF, and vitamin B12 deficiencies) could be eliminated. Fortification is one potential strategy to improve nutritional status and reduce the burden of anemia in this population.

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[RESUMEN]. Objetivo. Calcular la fracción atribuible poblacional a nivel nacional y regional y el número de casos de anemia que podrían prevenirse para tres factores de riesgo nutricional (deficiencia de hierro, folato eritrocitario y vitamina B12) en las mujeres en edad reproductiva en Belice. Metodología. Se llevó a cabo una encuesta probabilística nacional sobre características de los hogares y micronutrientes en la que se recopiló información sociodemográfica y de salud de 937 mujeres beliceñas no embarazadas de entre 15 y 49 años. Se extrajeron muestras de sangre para determinar los niveles de hemoglobina, ferritina, alfa–1–glucoproteína, folato eritrocitario y vitamina B12. En todos los análisis se emplearon ponderaciones muestrales y variables calculadas para tener en cuenta que se trataba de una encuesta con una muestra compleja. Se estimaron mediante regresión logística las razones de riesgos de prevalencia ajustados, que posteriormente se utilizaron para calcular la fracción atribuible poblacional con respecto a la anemia a nivel nacional y regional. Resultados. La prevalencia global de la anemia (hemoglobina <12 g/dl) fue del 21,2% (IC del 95%: 18,7– 25,3). La prevalencia de la anemia fue significativamente mayor en las mujeres con ferropenia (59,5%, IC del 95%: 48,7–69,5) que en las que no tenían ferropenia (15,2%, IC del 95%: 12,2, 18,3); razón de riesgos de prevalencia ajustados = 3.9, IC del 95%; 2,9–5,1). Las tres deficiencias nutricionales examinadas explicaban al 34,6% (IC del 95%: 22,1–47,1) de los casos de anemia. Se estima que si pudieran eliminarse todas estas deficiencias nutricionales, se prevendrían unos 5953 (IC del 95%: 3807–8114) casos de anemia. Conclusiones. Los resultados de este estudio sugieren que los casos de anemia en las mujeres en edad reproductiva de Belice podrían reducirse en un tercio si se pudieran eliminar tres factores de riesgo nutricionales modificables (deficiencias de hierro, folato eritrocitario y vitamina B12). Una posible estrategia para mejorar el estado nutricional y reducir la carga de la anemia en este grupo poblacional es en el enriquecimiento de los alimentos con suplementos.

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[RESUMO]. Objetivo. Estimar a fração atribuível populacional (FAP) nacional e regional e o potencial número de casos preveníveis de anemia para três fatores de risco nutricionais (deficiência de ferro, ácido fólico eritrocitário e vitamina B12) entre mulheres em idade fértil em Belize. Métodos. Realizou-se um inquérito probabilístico domiciliar nacional sobre micronutrientes, que coletou informações sociodemográficas e de saúde de 937 mulheres belizenhas não grávidas com idade entre 15 e 49 anos. Coletaram-se amostras de sangue para dosagem de hemoglobina, ferritina, alfa-1-glicoproteína (AGP), ácido fólico eritrocitário e vitamina B12. Todas as análises usaram variáveis de delineamento e ponderações amostrais para refletir um inquérito amostral complexo. Aplicou-se regressão logística para determinar razões ajustadas de risco de prevalência (RPa), que foram usadas para estimar a FAP nacional e regional para anemia. Resultados. A prevalência geral de anemia (hemoglobina <12 g/dL) foi de 21,2% (IC 95% [18,7–25,3]). A prevalência de anemia foi significativamente maior em mulheres com deficiência de ferro (59,5%, IC 95% [48,7–69,5]) que em mulheres sem deficiência de ferro (15,2%, IC 95% [12,2–18,3]); RPa 3,9, IC 95% [2,9– 5,1]). As três deficiências nutricionais analisadas contribuíram para 34,6% (IC 95% [22,1–47,1]) dos casos de anemia. Caso se eliminassem todas essas deficiências nutricionais, seria possível evitar cerca de 5.953 (IC 95% [3.807–8.114]) casos de anemia. Conclusões. Este estudo sugere que, nas mulheres belizenhas em idade fértil, os casos de anemia poderiam ser reduzidos em um terço caso fosse possível eliminar três fatores de risco nutricionais modificáveis (deficiência de ferro, ácido fólico eritrocitário e vitamina B12). A fortificação é uma possível estratégia para melhorar o estado nutricional e reduzir a carga de anemia nessa população.

Asunto(s)

Anemia , Factores de Riesgo , Salud de la Mujer , Anemia Ferropénica , Ácido Fólico , Deficiencia de Vitamina B 12 , Belice , Factores de Riesgo , Salud de la Mujer , Anemia Ferropénica , Ácido Fólico , Deficiencia de Vitamina B 12 , Belice , Factores de Riesgo , Salud de la Mujer , Anemia Ferropénica , Deficiencia de Vitamina B 12

RESUMEN

BACKGROUND: Gestational weight gain below or above the Institute of Medicine recommendations has been associated with adverse perinatal and neonatal outcomes. Very few studies have evaluated the association between serum and red blood cell folate concentrations and gestational weight gain in adolescents. Additionally, zinc deficiency during pregnancy has been associated with impaired immunity, prolonged labor, preterm and post-term birth, intrauterine growth restriction, low birth weight, and pregnancy-induced hypertension. OBJECTIVE: The purpose of our study is to evaluate the association between serum concentrations of zinc, serum folate, and red blood cell folate, with the increase in gestational weight and the weight and length of the newborn in a group of adolescent mothers from Mexico City. RESULTS: In our study, 406 adolescent-neonate dyads participated. The adolescents' median age was 15.8 years old. The predominant socioeconomic level was middle-low (57.8%), single (57%), 89.9% were engaged in home activities, and 41.3% completed secondary education. Excessive gestational weight gain was observed in 36.7% of cases, while insufficient gestational weight gain was noted in 38.4%. Small for gestational age infants were observed in 20.9% of the sample. Low serum folate (OR 2.1, 95% CI 1.3-3.3), decreased red blood cell folate (OR 1.6, 95% CI 1.0-2.6), and reduced serum zinc concentrations (OR 3.3, 95% CI 2.1-5.2) were associated with insufficient gestational weight gain. Decreased serum zinc levels (OR 1.2, 95% CI 1.2-3.4) were linked to an increased probability of delivering a baby who is small for their gestational age. CONCLUSIONS: Low serum folate, red blood cell folate, and serum zinc concentrations were associated with gestational weight gain and having a small gestational age baby. Both excessive and insufficient gestational weight gain, as well as having a small gestational age baby, are frequent among adolescent mothers.

Asunto(s)

Peso al Nacer , Eritrocitos , Ácido Fólico , Ganancia de Peso Gestacional , Zinc , Humanos , Femenino , Zinc/sangre , Zinc/deficiencia , Adolescente , Embarazo , Ácido Fólico/sangre , Recién Nacido , México , Recién Nacido Pequeño para la Edad Gestacional/sangre , Embarazo en Adolescencia/sangre

RESUMEN

Polycystic ovary syndrome (PCOS) is a common endocrine disorder that affects women of reproductive age. Many women with PCOS have been found to have an unbalanced diet and deficiencies in essential nutrients. This study aimed to assess the levels of folate and vitamin B12 (B12) and their relationship with metabolic factors in women with PCOS. Anthropometric, clinical, and genetic analyses were conducted to evaluate markers related to one-carbon metabolism in women with PCOS and in a control group. The PCOS group had a higher BMI and HOMA-IR (1.7 vs. 3.1; p < 0.0001). HDL cholesterol levels were 23% lower and triglyceride levels were 74% higher in women with PCOS. Although there were no significant differences in folate and B12 levels between the PCOS and control groups, over 60% of women with PCOS had low B12 levels (<300 pg/mL) and high homocysteine levels. In addition, the MTHFR A1298C and C677T polymorphisms were not associated with PCOS. Moreover, erythrocyte folate levels were positively correlated with fasting glucose, triglycerides, and free androgen index, and negatively correlated with SHBG and LH levels. These results suggest that B vitamins may be associated with the metabolic phenotype in PCOS. This study emphasizes the potential link between folate, vitamin B12, and metabolic and hormonal outcomes in women with PCOS.

Asunto(s)

Ácido Fólico , Síndrome del Ovario Poliquístico , Vitamina B 12 , Humanos , Femenino , Síndrome del Ovario Poliquístico/sangre , Síndrome del Ovario Poliquístico/genética , Vitamina B 12/sangre , Ácido Fólico/sangre , Adulto , Chile/epidemiología , Adulto Joven , Triglicéridos/sangre , Homocisteína/sangre , Índice de Masa Corporal , Glucemia/metabolismo , Metilenotetrahidrofolato Reductasa (NADPH2)/genética , Resistencia a la Insulina , HDL-Colesterol/sangre , Estudios de Casos y Controles , Biomarcadores/sangre

RESUMEN

Herein, we present a thorough examination of the impact of maternal nutrition on fetal and infant neurodevelopment, focusing on specific nutrients and their critical roles in perinatal and pediatric health. Through a comprehensive narrative review of the literature, this study highlights the importance of a balanced maternal diet rich in nutrients like eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), folic acid, iron, and iodine in shaping children's neurological functions. Key findings underscore the influence of maternal nutrition during pregnancy and the peri-gestational period on children's cognitive, motor, speech, and socio-emotional development. Deficiencies in essential nutrients, such as DHA, are linked to adverse long-lasting outcomes such as premature birth and intrauterine growth restriction, where a suitable intake of iron and folic acid is vital to prevent neural tube defects and promote healthy brain development. We highlight areas requiring further investigation, particularly regarding iodine's impact and the risks associated with alcohol consumption during pregnancy. In conclusion, this research sheds light on our current understanding of maternal nutrition and child neurodevelopment, offering valuable insights for health professionals and researchers.

Asunto(s)

Desarrollo Infantil , Desarrollo Fetal , Fenómenos Fisiologicos Nutricionales Maternos , Humanos , Embarazo , Femenino , Desarrollo Fetal/efectos de los fármacos , Desarrollo Fetal/fisiología , Desarrollo Infantil/efectos de los fármacos , Desarrollo Infantil/fisiología , Yodo/deficiencia , Yodo/administración & dosificación , Dieta/métodos , Lactante , Recién Nacido , Encéfalo/crecimiento & desarrollo , Encéfalo/efectos de los fármacos , Ácido Fólico/administración & dosificación , Estado Nutricional , Ácidos Docosahexaenoicos/administración & dosificación

RESUMEN

Systemic lupus erythematosus (SLE) patients present a high prevalence of cardiometabolic risk, associated with worse clinical manifestations and mortality. Folate, an essential micronutrient that participates in vital immune cellular functions, could positively affect the cardiometabolic and disease risk in SLE, through the methylenetetrahydrofolate reductase (MTHFR) enzyme, which participates in the folate metabolism, where single nucleotide variants (SNVs) have been described as a potential genetic risk factor for SLE. The aim of this study was to determine the association of the c.+677 C>T (rs1801133) and c.+1298 A>C (rs1801131) MTHFR genetic variants with cardiometabolic risk and clinical disease variables in SLE patients. A case-control study was conducted on 394 unrelated Mexican-mestizo women: 199 with SLE according to the 1997 SLE-ACR criteria and 196 control subjects (CS). Folic acid and homocysteine levels were evaluated by immunoassays. Genotyping of MTHFR genetic variants was carried out by allelic discrimination. No significant differences were found for folic acid (p = .15) and homocysteine serum levels (p = .59) between groups. According to the CC c.+677 MTHFR genotype, this was associated with low cardiovascular disease (CVD) risk by the Castelli index (OR = 0.42; p = .03) in SLE patients. The TC (OR = 1.3; p = .03) and the TA (OR = 1.6; p < .01) haplotypes from c.+677 C>T plus c.+1298 MTHFR were associated with SLE risk, while the CC MTHFR haplotype (OR = 0.5; p = .01) was found as a non-risk factor for the disease. In conclusion, the TC and the TA MTHFR haplotypes are associated with disease risk; meanwhile, the CC c.+677 MTHFR genotype confers lower cardiometabolic risk in Mexican-mestizo SLE patients.

Asunto(s)

Ácido Fólico , Predisposición Genética a la Enfermedad , Lupus Eritematoso Sistémico , Metilenotetrahidrofolato Reductasa (NADPH2) , Polimorfismo de Nucleótido Simple , Humanos , Lupus Eritematoso Sistémico/genética , Lupus Eritematoso Sistémico/complicaciones , Metilenotetrahidrofolato Reductasa (NADPH2)/genética , Femenino , Estudios Transversales , Estudios de Casos y Controles , Adulto , México/epidemiología , Persona de Mediana Edad , Ácido Fólico/sangre , Homocisteína/sangre , Enfermedades Cardiovasculares/genética , Enfermedades Cardiovasculares/etiología , Enfermedades Cardiovasculares/epidemiología , Factores de Riesgo Cardiometabólico , Genotipo , Factores de Riesgo , Adulto Joven

RESUMEN

Gastric cancer has been demonstrating a reduction in the number of cases over the past decades, largely attributed to advancements in public health practices and increased accessibility to educational initiatives for the general population. Nevertheless, it persists as the third leading cause of mortality globally among both men and women. These fatalities are typically associated with delayed disease detection. The current study assessed the levels of homocysteine, vitamin B12, and folic acid as a means of establishing a screening biomarker profile that could be integrated into routine testing protocols to facilitate swift diagnosis of the illness. A total of 207 control subjects and 207 individuals with gastric cancer were scrutinized, with biochemical measurements conducted using chemiluminescence for homocysteine, folic acid, and vitamin B12. The two groups were matched based on age, tumor location, subtype, tumor classification, presence of Epstein-Barr Virus infection (EBV), and Helicobacter pylori (H. pylori). Significant statistical variances were identified in the mean levels of the triad of substances among cancer patients when compared to the control group for all corresponding variables. In conclusion, our study indicated that analyzing the triad of homocysteine, vitamin B12, and folic acid holds diagnostic value for gastric cancer and could potentially serve as an effective screening marker for this type of cancer in the future.

Asunto(s)

Biomarcadores de Tumor , Detección Precoz del Cáncer , Ácido Fólico , Homocisteína , Neoplasias Gástricas , Vitamina B 12 , Humanos , Neoplasias Gástricas/diagnóstico , Vitamina B 12/sangre , Ácido Fólico/sangre , Homocisteína/sangre , Masculino , Femenino , Persona de Mediana Edad , Biomarcadores de Tumor/sangre , Anciano , Adulto , Estudios de Casos y Controles

RESUMEN

Emerging evidence suggests that elevated levels of folic acid in the bloodstream may confer protection against Wuhan-SARS-CoV-2 infection and mitigate its associated symptoms. Notably, two comprehensive studies of COVID-19 patients in Israel and UK uncovered a remarkable trend, wherein individuals with heightened folic acid levels exhibited only mild symptoms and necessitated no ventilatory support. In parallel, research has underscored the potential connection between decreased folic acid levels and the severity of Covid-19 among hospitalized patients. Yet, the underlying mechanisms governing this intriguing inhibition remain elusive. In a quest to elucidate these mechanisms, we conducted a molecular dynamics simulation approach followed by a Raman spectroscopy study to delve into the intricate interplay between the folic acid metabolite, 7,8-dihydrofolate (DHF), and the angiotensin-converting enzyme ACE2 receptor, coupled with its interaction with the receptor-binding domain (RBD) of the Wuhan strain of SARS-CoV-2. Through a meticulous exploration, we scrutinized the transformation of the ACE2 + RBD complex, allowing these reactants to form bonds. This was juxtaposed with a similar investigation where ACE2 was initially permitted to react with DHF, followed by the exposure of the ACE2 + DHF complex to RBD. We find that DHF, when bonded to ACE2, functions as a physical barrier, effectively inhibiting the binding of the Wuhan strain RBD. This physicochemical process offers a cogent explanation for the observed inhibition of host cell infection in subjects receiving supplementary folic acid doses, as epidemiologically substantiated in multiple studies. This study not only sheds light on a potential avenue for mitigating SARS-CoV-2 infection but also underscores the crucial role of folic acid metabolites in host-virus interactions. This research paves the way for novel therapeutic strategies in the battle against COVID-19 and reinforces the significance of investigating the molecular mechanisms underlying the protective effects of folic acid in the context of viral infections.

Asunto(s)

COVID-19 , Ácido Fólico , SARS-CoV-2 , Humanos , Enzima Convertidora de Angiotensina 2 , Ácido Fólico/análogos & derivados , Ácido Fólico/metabolismo , Ácido Fólico/farmacología , Simulación de Dinámica Molecular , Unión Proteica , Espectrometría Raman

RESUMEN

PURPOSE: To our knowledge, there are very few studies evaluating if the levels of folate modify the risk of cervical intraepithelial neoplasia grade 2 and higher (CIN2+ and CIN3+) associated with the levels of HPV genome methylation, two cofactors related to single carbon metabolism and independently associated with cervical cancer in previous studies. We conducted a case-control study nested in a three-arm randomized clinical pragmatic trial (ASCUS-COL trial) to evaluate the risk of CIN3+ associated with methylation levels according to serum folate concentrations. METHODS: Cases (n = 155) were women with histologically confirmed CIN2+ (113 CIN2, 38 CIN3, and 4 SCC) and controls were age and follow-up time at diagnosis-matched women with histologically confirmed ≤ CIN1 (n = 155), selected from the 1122 hrHPV + women of this trial. The concentrations of serum folate were determined by the radioimmunoassay SimulTRAC-SNB-VitaminB12/Folate-RIAKit and the methylation levels by the S5 classifier. Stepwise logistic regression models were used to estimate the association between folate or methylation levels and CIN2+ or CIN3+. The joint effect of folate levels and methylation on the risk of CIN3+ was estimated using combinations of categorical stratifications. RESULTS: Folate levels were significantly lower in women with CIN3+ than in other diagnostic groups (p = 0.019). The risk of CIN3+ was eight times higher (OR 8.9, 95% CI 3.4-24.9) in women with folate deficiency and high methylation levels than in women with normal folate and high methylation levels (OR 1.4, 95% CI 0.4-4.6). CONCLUSION: High methylation and deficient folate independently increased the risk of CIN3+ while deficient folate combined with high methylation was associated with a substantially elevated risk of CIN3+.

Asunto(s)

Células Escamosas Atípicas del Cuello del Útero , Deficiencia de Ácido Fólico , Displasia del Cuello del Útero , Femenino , Humanos , Estudios de Casos y Controles , Metilación de ADN , Ácido Fólico , Deficiencia de Ácido Fólico/genética , Displasia del Cuello del Útero/diagnóstico , Displasia del Cuello del Útero/genética , Displasia del Cuello del Útero/patología

RESUMEN

INTRODUCTION: The placenta provides nutrients to the fetus, and it has protective effects against harmful substances. Unhealthy maternal diets and toxic agents might increase free radical (FR) production. Elevated FR levels are associated with a high risk of oxidative stress, which may cause DNA damage. DNA might be oxidized in the placenta, occasionally affecting its methylation profile due to 8-hidroxy-2'-deoxyguanosine formation. METHODS: This study assessed 130 mothers and their children. The maternal's nutritional patterns were determined using the Food Frequency Questionnaire. Information on smoking and alcohol consumption was collected during the medical examination. Data on placental DNA were obtained to determine the MTHFR 677C/T genotype and the proportion of placental DNA methylation (pDNAm). RESULTS: Consumption of vitamins and folic acid was above 85%. The pDNAm was found to be correlated with gestational age and coffee intake. Mothers with a smoking history had a low pDNAm. Placentas with the TT genotype had a higher but not significant pDNAm. In the placentas with the CC/CT genotype, the pDNAm was positively associated with carbohydrate and biotin intake. However, the TT genotype was negatively associated with folate and vegetable intake. DISCUSSION: The pDNAm was positively associated with coffee intake, but not with macro-, and micronutrient intake. However, it was negatively associated with cigarette smoking. The placentas with the CC/CT genotype had a lower pDNAm than those with the TT genotype. In the placentas with the CC/CT or TT genotype, methylation was positively, and negatively associated with micro- or macronutrients, respectively.

Asunto(s)

Metilación de ADN , Placenta , Niño , Humanos , Femenino , Embarazo , Café , Dieta , Genotipo , Ácido Fólico , ADN , Fumar/efectos adversos , Metilenotetrahidrofolato Reductasa (NADPH2)/genética

RESUMEN

Abstract Nanoparticles are considered viable options in the treatment of cancer. This study was conducted to investigate the effect of magnetite nanoparticles (MNPs) and magnetite folate core shell (MFCS) on leukemic and hepatocarcinoma cell cultures as well as their effect on the animal model of acute myelocytic leukemia (AML). Through current study nanoparticles were synthesized, characterized by various techniques, and their properties were studied to confirm their nanostructure. Invivo study, nanoparticles were evaluated to inspect their cytotoxic activity against SNU-182 (human hepatocellular carcinoma), K562 (human leukemia), and THLE2 (human normal epithelial liver) cells via MTT test. Apoptotic signaling proteins Bcl-2 and Caspase-3 expression were inspected through RT-PCR method. A cytotoxic effect of MNPs and MFCS was detected in previous cell cultures. Moreover, the apoptosis was identified through significant up-regulation of caspase-3, with Bcl-2 down-regulation. Invitro study, AML was induced in rats by N-methyl-N-nitrosourea followed by oral treatment with MNPS and MFCS. Biochemical indices such as aspartate and alanine amino transferases, and lactate dehydrogenase activities, uric acid, complete blood count, and Beta -2-microglubulin were assessed in serum. Immunophenotyping for CD34 and CD38 detection was performed. Liver, kidney, and bone marrow were microscopically examined. Bcl-2 promoter methylation, and mRNA levels were examined. Although, both MNPs and MFCS depict amelioration in biochemical parameters, MFCS alleviated them toward normal control. Anticancer activity of MNPs and MFCS was approved especially for AML. Whenever, administration of MFCS was more effective than MNPs. The present work is one of few studies used MFCS as anticancer agent.

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Resumo Nanopartículas são consideradas opções viáveis ​​no tratamento do câncer. Este estudo foi conduzido para investigar o efeito de nanopartículas de magnetita (MNPs) e núcleo de folato de magnetita (MFCS) em culturas de células leucêmicas e de hepatocarcinoma, bem como seu efeito no modelo animal de leucemia mielocítica aguda (LMA). Através do atual estudo, nanopartículas foram sintetizadas, caracterizadas por várias técnicas, e suas propriedades foram estudadas para confirmar sua nanoestrutura. No estudo in vivo, as nanopartículas foram avaliadas para inspecionar sua atividade citotóxica contra células SNU-182 (carcinoma hepatocelular humano), K562 (leucemia humana) e THLE2 (fígado epitelial humano normal) por meio do teste MTT. A expressão das proteínas sinalizadoras apoptóticas Bcl-2 e Caspase-3 foram inspecionadas através do método RT-PCR. Um efeito citotóxico de MNPs e MFCS foi detectado em culturas de células anteriores. Além disso, a apoptose foi identificada por meio de regulação positiva significativa da Caspase-3, com regulação negativa de Bcl-2. No estudo in vitro, a AML foi induzida em ratos por N-metil-N-nitrosoureia seguida por tratamento oral com MNPS e MFCS. Índices bioquímicos como aspartato e alanina aminotransferases e atividades de lactato desidrogenase, ácido úrico, hemograma completo e Beta-2-microglubulina foram avaliados no soro. A imunofenotipagem para detecção de CD34 e CD38 foi realizada. Fígado, rim e medula óssea foram examinados microscopicamente. A metilação do promotor Bcl-2 e os níveis de mRNA foram examinados. Embora tanto os MNPs quanto os MFCS representem uma melhora nos parâmetros bioquímicos, o MFCS os aliviou em direção ao controle normal. A atividade anticâncer de MNPs e MFCS foi aprovada especialmente para AML. Sempre, a administração de MFCS foi mais eficaz do que MNPs. O presente trabalho é um dos poucos estudos que utilizou o MFCS como agente anticâncer.

Asunto(s)

Animales , Ratas , Nanopartículas de Magnetita , Neoplasias Hepáticas , Compuestos Férricos , Ácido Fólico

RESUMEN

OBJECTIVE: To verify whether folic acid supplementation during pregnancy is associated with the occurrence of maternal depressive symptoms at three months postpartum, in the 2015 Pelotas Birth Cohort. METHODS: This study included 4,046 women, who were classified into three groups: did not use folic acid supplementation during pregnancy; used during only one trimester of pregnancy; and used for two or three trimesters. Depressive symptoms were assessed at three months postpartum using the Edinburgh Postnatal Depression Scale (EPDS), at cutoff points ≥ 10 (mild symptoms) and ≥ 13 (moderate to severe intensity). RESULTS: The overall prevalence of mild symptoms was of 20.2% (95%CI 19.0-21.5), and moderate and severe was 11% (95%CI 10.0-12.0). The prevalence of EPDS ≥ 10 was of 26.8% (95%CI 24.0-29.5) among women who did not use folic acid and 18.1% for both those who used it during one trimester of pregnancy (95%CI 16.1-20.1) and those who used it for two or three trimesters (95%CI 16.0-20.2). The prevalence of EPDS ≥ 13 was of 15.7% (95%CI 13.5-17.9) in those who did not use folic acid, 9.1% (95%CI 7.5-10.6) in those who used it for one trimester, and 9.4% (95%CI 7.8-11.0) in those who used it for two or three trimesters. In the adjusted analyses, there was no statistically significant association between the use of folic acid during pregnancy and the occurrence of depressive symptoms at three months postpartum. CONCLUSION: There was no association between folic acid supplementation during pregnancy and postpartum depression at three months.

Asunto(s)

Depresión Posparto , Depresión , Embarazo , Femenino , Humanos , Depresión/epidemiología , Depresión/diagnóstico , Brasil/epidemiología , Periodo Posparto , Depresión Posparto/epidemiología , Ácido Fólico , Prevalencia , Suplementos Dietéticos

RESUMEN

BACKGROUND: DNA methylation patterns are directly associated with diverse metabolic disorders. The status of methyl-donor micronutrients has been associated with DNA methylation levels, and altered ingestion of folate, choline, betaine, B vitamins and methionine may impact genes both globally and at the level of promoter regions. Despite this, the role of methyl-donor micronutrient supplementation on DNA methylation profiles is currently unclear. OBJECTIVES: The aims of this systematic review and meta-analysis were to identify and synthesize the evidence about methyl-donor nutrient supplementation on DNA methylation. METHODS: A systematic literature search was performed in Medline, Embase, Scopus, and Web of Science databases with a combination of terms related to DNA methylation assessment, supplementation, and methyl-donor nutrients. Studies (in vitro, animal models, or human clinical trials) were included if DNA methylation levels after any kind of methyl-donor micronutrient supplementation or treatment was investigated. Studies were assessed for bias using Revised Cochrane risk-of-bias tool for randomized trials, risk-of-bias in Non-randomized Studies of Interventions or Systematic Review Centre for Laboratory Animal Experimentation tools. Data were extracted from studies measuring DNA methylation levels in any sample or tissue, following any kind of methyl-donor micronutrient supplementation or treatment. Separate random-effects meta-analyses were performed for animal model studies and human clinical trials that examined the effects of folic acid supplementation on DNA methylation. RESULTS: Fifty-seven studies were included in this systematic review: 18 human clinical trials, 35 in animal model, and 4 in vitro studies. Concerning overall risk of bias, most of the studies were classified as "high risk" or "some concerns." Meta-analysis with meta-regression from studies in animal models showed that folic acid dose significantly affected DNA methylation and that high and very high doses showed increases in DNA methylation when compared to low doses. However, meta-analysis of human clinical trials showed that folic acid supplementation did not promote significant changes in DNA methylation when compared to placebo. CONCLUSION: Folic acid supplementation may change global DNA methylation levels in animals supplemented with high, as compared to low, doses. Heterogeneity in studies and supplementation protocols make it difficult to establish clinical recommendations. However, these effects, even if small, might be of clinical importance in the management of patients with diseases related to DNA hypomethylation.

Asunto(s)

Metilación de ADN , Complejo Vitamínico B , Humanos , Animales , Ácido Fólico , Suplementos Dietéticos , Micronutrientes