Folic acid supplementation in pregnancy and implications in health and disease

Maternal and Perinatal Factors Associated With Childhood Brain Tumors: A Case-Control Study in Vietnam

INTRODUCTION

Brain cancer is the leading cause of cancer-related deaths in children and the majority of childhood brain tumors are diagnosed without determination of their underlying etiology. Little is known about risk factors for childhood brain tumors in Vietnam. The objective of this case-control study was to identify maternal and perinatal factors associated with brain tumors occurring in young Vietnamese children and adolescents.

METHODS

We conducted a hospital-based case-control study at Viet Duc University Hospital in Hanoi, Vietnam. Cases consisted of children with brain tumors aged 0-14 years old admitted to the hospital from January 2020 to July 2022 while the controls were age and sex-matched hospitalized children diagnosed with head trauma. Perinatal characteristics were abstracted from hospital medical records and maternal medical, behavioral, and sociodemographic factors were collected through in-person interviews. Conditional logistic regression models were used to examine maternal and perinatal factors associated with childhood brain tumors.

RESULTS

The study sample included 220 children (110 cases and 110 controls) whose average age was 8.9 years and 41.8% were girls. Children born to mothers aged greater than 30 years at the time of the child's birth had a higher risk of childhood brain tumors compared to those born to mothers aged from 18 to 30 years old (OR = 2.55; 95% CI: 1.13-5.75). Additionally low maternal body mass index prior to the current pregnancy of <18.5 kg/m2 significantly increased the odds of having a child with a brain tumor in relation to normal maternal body mass index from 18.5-22.9 kg/m2 (OR = 3.19; 95% CI: 1.36 - 7.50).

CONCLUSION

Advanced maternal age and being markedly underweight were associated with an increased odds of having a child with a brain tumor. A population-based study with larger sample size is needed to confirm and extend the present findings.

Advances in Folic Acid Biosensors and Their Significance in Maternal, Perinatal, and Paediatric Preventive Medicine

Auxotrophic primates like human beings rely on exogenous dietary vitamin B9 supplementation to meet their metabolic demands. Folates play a crucial role in nucleotide synthesis and DNA methylation. Maternal folate deficiency causes several pregnancy-related complications, perinatal defects, and early childhood cognitive impairments. New evidence suggests excess FA is a potential risk factor resulting in unfavourable genomic and epigenomic alterations. Thus, it is essential to revisit the need to consistently monitor maternal folate levels during pregnancy. Yet, to date, no point-of-care folate-monitoring biosensor is commercially available. Here, we critically appraise the advances in folate biosensors to understand the translational gaps in biosensor design. Further, our review sheds light on the potential role of folate biosensors in strengthening maternal, perinatal, and child healthcare.

Maternal intake of folate and folic acid during pregnancy and pubertal timing in girls and boys: A population-based cohort study

BACKGROUND

Folate is essential for normal foetal development as it plays an important role for gene expression during different periods of foetal development. Thus, prenatal exposure to folate may have a programming effect on pubertal timing.

OBJECTIVES

To study the association between maternal intake of folate during pregnancy and pubertal timing in girls and boys.

METHODS

We studied 6585 girls and 6326 boys from a Danish population-based Puberty Cohort, 2000-2021. Information on maternal intake of folate from diet and folic acid from supplements was obtained from a food-frequency questionnaire in mid-pregnancy, and total folate was calculated as dietary folate equivalents. Information on age at menarche in girls, age at first ejaculation and voice break in boys, and Tanner stages, acne and axillary hair in both girls and boys was obtained every 6 months throughout puberty. We estimated mean monthly differences according to exposure groups for each pubertal milestone in addition to a combined estimate for the average age at attaining all pubertal milestones using multivariable interval-censored regression models. Total folate was analysed in quintiles, continuous and as restricted cubic splines.

RESULTS

Maternal intake of total folate in mid-pregnancy was not associated with pubertal timing in girls (combined estimate for overall pubertal timing per standard deviation (SD 325 μg/day) decrease in maternal intake of total folate: -0.14 months (95% confidence interval [CI] -0.51, 0.22)). Boys had slightly later overall pubertal timing per standard deviation (SD 325 μg/day) decrease in maternal intake of total folate (combined estimate: 0.40 months, 95% CI 0.01, 0.72). Spline plots supported these findings.

CONCLUSIONS

Prenatal exposure to low maternal intake of total folate in mid-pregnancy was not associated with pubertal timing in girls but associated with slightly later pubertal timing in boys. This minor delay is likely not of clinical importance.

Brain Trauma and the Secondary Cascade in Humans: Review of the Potential Role of Vitamins in Reparative Processes and Functional Outcome

An estimated sixty-nine million people sustain a traumatic brain injury each year. Trauma to the brain causes the primary insult and initiates a secondary biochemical cascade as part of the immune and reparative response to injury. The secondary cascade, although a normal physiological response, may also contribute to ongoing neuroinflammation, oxidative stress and axonal injury, continuing in some cases years after the initial insult. In this review, we explain some of the biochemical mechanisms of the secondary cascade and their potential deleterious effects on healthy neurons including secondary cell death. The second part of the review focuses on the role of micronutrients to neural mechanisms and their potential reparative effects with regards to the secondary cascade after brain injury. The biochemical response to injury, hypermetabolism and excessive renal clearance of nutrients after injury increases the demand for most vitamins. Currently, most research in the area has shown positive outcomes of vitamin supplementation after brain injury, although predominantly in animal (murine) models. There is a pressing need for more research in this area with human participants because vitamin supplementation post-trauma is a potential cost-effective adjunct to other clinical and therapeutic treatments. Importantly, traumatic brain injury should be considered a lifelong process and better evaluated across the lifespan of individuals who experience brain injury.

The association between serum folate and gestational diabetes mellitus: a large retrospective cohort study in Chinese population

OBJECTIVE

To investigate the association between folate levels and the risk of gestational diabetes mellitus (GDM) risk during the whole pregnancy.

DESIGN

In this retrospective cohort study of pregnant women, serum folate levels were measured before 24 gestational weeks (GW). GDM was diagnosed between 24th and 28th GW based on the criteria of the International Association of Diabetes and Pregnancy Study Groups. General linear models were performed to examine the association of serum folate with plasma glucose (i.e. linear regressions) and risk of GDM (i.e. log-binomial regressions) after controlling for confounders. Restricted cubic spline regression was conducted to test the dosage-response relationship between serum folate and the risk of GDM.

SETTING

A sigle, urban hospital in Shanghai, China.

PARTICIPANTS

A total of 42 478 women who received antenatal care from April 2013 to March 2017 were included.

RESULTS

Consistent positive associations were observed between serum folate and plasma glucose levels (fasting, 1-h, 2-h). The adjusted relative risks (RR) and 95 % CI of GDM across serum folate quartiles were 1·00 (reference), 1·15 (95 % CI (1·04, 1·26)), 1·40 (95 % CI (1·27, 1·54)) and 1·54 (95 % CI (1·40, 1·69)), respectively (P-for-trend < 0·001). The positive association between serum folate and GDM remained when stratified by vitamin B12 (adequate v. deficient groups) and the GW of serum folate measurement (≤13 GW v. >13 GWs).

CONCLUSIONS

The findings of this study may provide important evidence for the public health and clinical guidelines of pregnancy folate supplementation in terms of GDM prevention.

Folic acid ameliorates synaptic impairment following cerebral ischemia/reperfusion injury via inhibiting excessive activation of NMDA receptors

Folic acid, a water-soluble B-vitamin, has been demonstrated to decrease the risk of first stroke and improve its poor prognosis. However, the molecular mechanisms responsible for the beneficial effect of folic acid on recovery from ischemic insult remain largely unknown. Excessive activation of the N-methyl-d-aspartate receptors (NMDARs) has been shown to trigger synaptic dysfunction and excitotoxic neuronal death in ischemic brains. Here, we hypothesized that the effects of folic acid on cognitive impairment may involve the changes in synapse loss and NMDAR expression and function following cerebral ischemia/reperfusion injury. The ischemic stroke models were established by middle cerebral artery occlusion/reperfusion (MCAO/R) and by oxygen-glucose deprivation and reperfusion (OGD/R)-treated primary neurons. The results showed that folic acid supplemented diets (8.0 mg/kg for 28 days) improved cognitive performances of rats after MCAO/R. Folic acid also caused a reduction in the number of neuronal death, an increase in the number of synapses and the expressions of synapse-related proteins including SNAP25, Syn, GAP-43 and PSD95, and a decrease in p-CAMKII expression in ischemic brains. Similar changes in synaptic functions were observed in folic acid (32 µM)-treated OGD/R neurons. Furthermore, NMDA treatment reduced folic acid-induced upregulations of synapse-associated proteins and Ca²⁺ influx, whereas downregulations of NMDARs by NR1 or both NR2A and NR2B siRNA further enhanced the expressions of synapse-related proteins raised by folic acid in OGD/R neurons. Our findings suggest that folic acid improves cognitive dysfunctions and ameliorates ischemic brain injury by strengthening synaptic functions via the NMDARs.

Metabolic enhancement of the one carbon metabolism (OCM) in bovine oocytes IVM increases the blastocyst rate: evidences for a OCM checkpoint

The one carbon metabolism (OCM) has a primary role in the process of oocyte maturation. In this study bovine oocytes were cultured for 24 h, up to MII stage, with standard medium supplemented or not with 8 metabolic enhancers of the OCM and the MII and blastocyst rate were compared. Additional analyses were performed on matured oocytes, cumulus cells, zygotes and blastocysts. The OCM supplementation increased the blastocyst rate derived from in vitro fertilization. The mitochondrial mass and DNMT3a protein expression were increased whereas DNA fragmentation decreased in matured oocytes. DNA methylation in female pronucleus of zygotes was increased. The supplementation did not directly affect the redox balance as ROS and GSH in matured oocytes and homocysteine in the spent medium were unchanged. The supplementation of the oocytes with metabolic enhancers of the OCM may increase the yield from the culture, likely due to improved DNA methylation and epigenetic programming. The lack of effects on MII rate with huge differences appearing at the blastocyst stage suggest the existence of a OCM metabolic check point that hampers oocytes progression to blastocyst post-fertilization, if they were not properly primed at the time of maturation.

Sodium-to-Potassium Ratio as an Indicator of Diet Quality in Healthy Pregnant Women

This study aimed to investigate diet quality in healthy pregnant women based on the Na-to-K ratio from 24 h urine sample and food frequency questionnaire (FFQ), to compare dietary micro- and macronutrient intake with current nutritional recommendations (RDA), and to investigate whether gestational weight gain (GWG) is associated with Na-to-K ratio and diet quality during pregnancy in general. Sixty-four healthy pregnant women between 37 and 40 weeks of gestation participated in the study. Participants' GWG, body composition, molar 24 h urine Na-to-K ratio, and FFQ data on average daily total energy, food groups, and micro-/macronutrient intake were obtained. A Na-to-K ratio of 2.68 (1.11-5.24) does not meet nutrition quality and is higher than the WHO recommendations due to excessive sodium and insufficient potassium intake. FFQ Na-to-K ratio was associated with a higher daily intake of soups, sauces, cereals, fats, and oils and a low intake of fruit and non-alcoholic beverages. A total of 49% of pregnant women exhibited excessive GWG, which was attributed to the increase in adipose tissue mass. GWG was not associated with total energy but may be the result of insufficient physical activity during pregnancy. Daily intake of vitamin D, vitamin E, folate, niacin, riboflavin, calcium, iron, and zinc was suboptimal compared to RDA.

Periconceptional Mediterranean diet during pregnancy on children's health

During pregnancy, rapid and subtle physiological changes are observed from conception to birth. Nutrition and other lifestyle factors before and during pregnancy have been shown in the literature to influence the health of both mother and child. A healthy and varied diet during pregnancy can provide adequate energy and nutrients for both the mother and the growing fetus. Current research focuses on the periconceptional phase, which includes the early processes of gametogenesis, embryogenesis and placentation. A variety of abnormalities and pregnancy-related problems occur during this period, including congenital defects, fetal loss, miscarriage and preterm birth. A varied and balanced diet during periconception is important to maintain fetal development and growth. To date, numerous studies have been conducted to investigate the effects of consuming different nutrients, foods or food groups during pregnancy on the health of mother and child. For example, the Mediterranean diet is considered as a balanced, nutrient-rich diet due to the low consumption of meat products and fatty foods and the high consumption of vegetables, cheese, olive oil, fish, shellfish and little meat. While many studies have been conducted in the literature to investigate the effects of a Mediterranean diet during pregnancy on fetal health, the results have been inconclusive. The aim of this article is to review the current literature on the Mediterranean diet during pregnancy.

Vitamin Supplementation in Pre-Pregnancy and Pregnancy among Women-Effects and Influencing Factors in Romania

Introduction: The aim of the study was to identify the consumption of vitamin and folic acid supplements before and during pregnancy in a group of post-partum women (Romanian, Hungarian, and Roma) from Mureș County, Romania, and the influence of socio-economic and behavioral factors on the consumption of vitamins. Materials and Methods: This cross-sectional questionnaire-based study included 1278 post-partum women (during the three days of hospitalization for birth), average age 29.5, registered for giving birth in the three hospitals in Mureș County, 2015−2016. Results: In our sample, 69.58% of the interviewed women did not use any vitamin and folic acid supplements before pregnancy, while 30.70% did not use vitamin supplements during pregnancy. The lack of vitamin supplementation during pregnancy was associated with the low birth weight (<2500 g) of newborns (OR = 2.4, 95% CI [1.6−3.8]) and birth at under 36 weeks of gestation (OR = 0.5, 95% CI [0.2−0.8]). Conclusion: The use of vitamin supplements, including folic acid, continues to be deficient among Romanian women before getting pregnant, as well as during their pregnancy. We observed a lack of vitamin supplementation for pregnant women even if they were influenced by risk factors. This highlights the importance of promoting the benefits of vitamin supplementation equally among all subjects.

A review of transglycosylated compounds as food additives to enhance the solubility and oral absorption of hydrophobic compounds in nutraceuticals and pharmaceuticals

Transglycosylation has been used to modify the physicochemical properties of original compounds. As a result, transglycosylated compounds can form molecular aggregates in size ranges of a few nanometers in an aqueous medium when their concentrations exceed a specific level. Incorporating these hydrophobic compounds has been observed to enhance the solubility of hydrophobic compounds into aggregate structures. Thus, this review introduces four transglycosylated compounds as food additives that can enhance the solubility and oral absorption of hydrophobic compounds. Here, transglycosylated hesperidin, transglycosylated rutin, transglycosylated naringin, and transglycosylated stevia are the focus as representative substances. Significantly, we observed that amorphous formations containing hydrophobic compounds with transglycosylated compounds improved solubility and oral absorption compared to untreated hydrophobic compounds. Moreover, combining transglycosylated compounds with hydrophilic polymers or surfactants enhanced the solubilizing effects on hydrophobic compounds. Furthermore, the enhanced solubility of hydrophobic compounds improved their oral absorption. Transglycosylated compounds also influenced nanoparticle preparation of hydrophobic compounds as a dispersant. This study demonstrated the benefits of transglycosylated compounds in developing supplements and nutraceuticals of hydrophobic compounds with poor aqueous solubility.

Absorption and Tissue Distribution of Folate Forms in Rats: Indications for Specific Folate Form Supplementation during Pregnancy

Food fortification and folic acid supplementation during pregnancy have been implemented as strategies to prevent fetal malformations during pregnancy. However, with the emergence of conditions where folate metabolism and transport are disrupted, such as folate receptor alpha autoantibody (FRαAb)-induced folate deficiency, it is critical to find a folate form that is effective and safe for pharmacologic dosing for prolonged periods. Therefore, in this study, we explored the absorption and tissue distribution of folic acid (PGA), 5-methyl-tetrahydrofolate (MTHF), l-folinic acid (levofolinate), and d,l-folinic acid (Leucovorin) in adult rats. During absorption, all forms are converted to MTHF while some unconverted folate form is transported into the blood, especially PGA. The study confirms the rapid distribution of absorbed folate to the placenta and fetus. FRαAb administered, also accumulates rapidly in the placenta and blocks folate transport to the fetus and high folate concentrations are needed to circumvent or overcome the blocking of FRα. In the presence of FRαAb, both Leucovorin and levofolinate are absorbed and distributed to tissues better than the other forms. However, only 50% of the leucovorin is metabolically active whereas levofolinate is fully active and generates higher tetrahydrofolate (THF). Because levofolinate can readily incorporate into the folate cycle without needing methylenetetrahydrofolate reductase (MTHFR) and methionine synthase (MS) in the first pass and is relatively stable, it should be the folate form of choice during pregnancy, other disorders where large daily doses of folate are needed, and food fortification.

Epigenetic Effect of Maternal Methyl-Group Donor Intake on Offspring’s Health and Disease

Maternal exposure to some dietary and environmental factors during embryonic development can affect offspring’s phenotype and, furthermore, the risk of developing diseases later in life. One potential mechanism responsible for this early programming may be the modification of the epigenome, such as DNA methylation. Methyl-group donors are essential for DNA methylation and are shown to have an important role in fetal development and later health. The main goal of the present review is to summarize the available literature data on the epigenetic effect (DNA methylation) of maternal methyl-group donor availability on reproductivity, perinatal outcome, and later health of the offspring. In our literature search, we found evidence for the association between alterations in DNA methylation patterns caused by different maternal methyl-group donor (folate, choline, methionine, betaine) intake and reproductivity, birth weight, neural tube defect, congenital heart defect, cleft lip and palate, brain development, and the development of obesity and associated non-communicable diseases in later life. We can conclude that maternal methyl-group donor availability could affect offspring’s health via alterations in DNA methylation and may be a major link between early environmental exposure and the development of diseases in the offspring. However, still, further studies are necessary to confirm the associations and causal relationships.

Association between Fetal MTHFR A1298C (rs1801131) Polymorphism and Neural Tube Defects Risk: A Systematic Review and Meta-Analysis

BACKGROUND

The association of the fetal MTHFR A1298C (rs1801131) polymorphism and neural tube defects (NTDs) susceptibility has been widely demonstrated, but the results remain inconclusive. Thus, we performed a meta-analysis to investigate the association between fetal MTHFR A1298C polymorphism and NTDs risk.

METHODS

An electronic search of PubMed, web of science, SciELO, CNKI database for studies on the fetal MTHFR A1298C polymorphism and NTDs risk was performed up to March 30, 2020.

RESULTS

A total of 22 case-control studies with 3,224 fetuses with NTDs and 3,295 controls were selected. Overall, pooled data showed that the fetal MTHFR A1298C polymorphism was not significantly associated with risk an increased risk of NTDs in the global population. When stratified analysis by ethnicity, country of origin and NTDs type, still no statistically significant association was found.

CONCLUSIONS

Our pooled data emerged no evidence for significant association between fetal MTHFR A1298C polymorphism and NTDs risk.

Prevalence of iron and folic acid supplements consumption and associated factors among pregnant women in Eswatini: a multicenter cross-sectional study

Background

During pregnancy, nutritional requirements increase and if not met, pregnancy-related complications may manifest. To prevent these undesirable outcomes, the World Health Organization recommends daily oral iron and folic acid (IFA) supplementation as part of antenatal care. Despite this recommendation, the use of IFA supplements is still very low in several developing countries. Additionally, no prior information exists regarding the level of consumption of IFA in Eswatini. Thus, this study aimed to determine the prevalence of consumption of IFA supplements and to identify factors associated with the consumption of IFA supplements among pregnant women in Eswatini.

Methods

A cross-sectional questionnaire survey was conducted among 330 pregnant women aged ≥ 18 years in their third trimester in Eswatini. Participants were recruited from eight purposively selected healthcare facilities from July 2019 to October 2019. Good consumption was defined as consuming all or almost all IFA supplements throughout pregnancy.

Results

During the first trimester, 10.3 % of the participants consumed all or almost all IFA supplements. In the second and third trimesters, those who consumed all or almost all supplements were 37 and 39.7 %, respectively, for iron and 37.6 and 40.9 %, respectively, for folic acid. Barriers, including side effects, forgetfulness, safe previous pregnancies without IFA, others’ advice against consumption, IFA stock-outs, inability to meet transport costs, and inadequate supply of IFA tablets, contribute to low consumption of IFA. Multivariate logistic regression models showed that the barriers were inversely associated with good consumption of IFA supplements. Better knowledge and attitude toward IFA and older maternal age were positively associated with good consumption of IFA supplements.

Conclusions

Low consumption of IFA supplements in overall pregnancy is mainly owing to the late antenatal care attendance. Strategies such as establishing a preconception care unit and school-based provision of IFA may be helpful. It is evident that most women still lack knowledge, and some have negative attitudes about IFA supplements. Health education to raise awareness and emphasize the importance of starting antenatal care early as well as consuming supplements on time should be revisited and intensified. Multiple strategies such as including community health care workers for distributing IFA supplements, discussing with clients about the measures to reduce forgetfulness, advising ways to prevent and manage the side effects, providing subsidies to cover transport costs, and ensuring adequate supply of IFA supplements in facilities may need to be employed to reduce the identified barriers.

The Incoherent Fluctuation of Folate Pools and Differential Regulation of Folate Enzymes Prioritize Nucleotide Supply in the Zebrafish Model Displaying Folate Deficiency-Induced Microphthalmia and Visual Defects

Objective

Congenital eye diseases are multi-factorial and usually cannot be cured. Therefore, proper preventive strategy and understanding the pathomechanism underlying these diseases become important. Deficiency in folate, a water-soluble vitamin B, has been associated with microphthalmia, a congenital eye disease characterized by abnormally small and malformed eyes. However, the causal-link and the underlying mechanism between folate and microphthalmia remain incompletely understood.

Methods

We examined the eye size, optomotor response, intracellular folate distribution, and the expression of folate-requiring enzymes in zebrafish larvae displaying folate deficiency (FD) and ocular defects.

Results

FD caused microphthalmia and impeded visual ability in zebrafish larvae, which were rescued by folate and dNTP supplementation. Cell cycle analysis revealed cell accumulation at S-phase and sub-G1 phase. Decreased cell proliferation and increased apoptosis were found in FD larvae during embryogenesis in a developmental timing-specific manner. Lowered methylenetetrahydrofolate reductase (mthfr) expression and up-regulated methylenetetrahydrofolate dehydrogenase (NADP⁺-dependent)-1-like (mthfd1L) expression were found in FD larvae. Knocking-down mthfd1L expression worsened FD-induced ocular anomalies; whereas increasing mthfd1L expression provided a protective effect. 5-CH₃-THF is the most sensitive folate pool, whose levels were the most significantly reduced in response to FD; whereas 10-CHO-THF levels were less affected. 5-CHO-THF is the most effective folate adduct for rescuing FD-induced microphthalmia and defective visual ability.

Conclusion

FD impeded nucleotides formation, impaired cell proliferation and differentiation, caused apoptosis and interfered active vitamin A production, contributing to ocular defects. The developmental timing-specific and incoherent fluctuation among folate adducts and increased expression of mthfd1L in response to FD reflect the context-dependent regulation of folate-mediated one-carbon metabolism, endowing the larvae to prioritize the essential biochemical pathways for supporting the continuous growth in response to folate depletion.

Exposures associated with the onset of Kawasaki disease in infancy from the Japan Environment and Children's Study

Kawasaki disease (KD) is an acute systemic vasculitis that mainly affects infants and young children. The etiology of KD has been discussed for several decades; however, no reproducible risk factors have yet been proven. We used the Japan Environment and Children’s Study data to explore the association between the causal effects of exposure during the fetal and neonatal periods and KD onset. The Japan Environment and Children’s Study, a nationwide birth cohort study, has followed approximately 100,000 children since 2011. We obtained data on exposures and outcomes from the first trimester to 12 months after birth. Finally, we included 90,486 children who were followed for 12 months. Among them, 343 children developed KD. Multivariate logistic regression revealed that insufficient intake of folic acid during pregnancy (odds ratio [OR], 1.37; 95% CI 1.08–1.74), maternal thyroid disease during pregnancy (OR, 2.03; 95% CI 1.04–3.94), and presence of siblings (OR, 1.33; 95% CI 1.06–1.67) were associated with KD onset in infancy. In this study, we identified three exposures as risk factors for KD. Further well-designed studies are needed to confirm a causal relationship between these exposures and KD onset.

Determination of the effect of germination on the folate content of the seeds of some legumes using HPTLC-mass spectrometry-multivariate image analysis

Legumes are the main sources of folates which are not synthesized in the human body. The five folate species: 5-methyl tetrahydrofolate, tetrahydrofolate, pteroyl glutamate, 5-formyl tetrahydrofolate and 10-formyl tetrahydrofolate were quantitatively determined in legumes seeds and sprouts by a newly developed and validated high performance thin layer chromatography method. High resolution plate imaging hyphenated to mass spectrometry was exploited for fingerprint analysis of tested samples. Results indicated that germination of all seeds resulted in a 2.5-4 fold increase in the content of total folates as well as the individual vitamers. The total amount of folate reached a maximum on the fifth day in the case of black-eyed peas (861 μg/100 g Fresh Weight), white beans (755 μg/100 g FW) and brown lentils (681 μg/100 g FW). 5-CH₃-H₄ folate was found to be the most dominating folate species reaching its maximum content in day 5 sprouts of black-eyed peas (490 μg/100 g FW).

The toxic side of one-carbon metabolism and epigenetics

One-carbon metabolism is a central metabolic hub that provides one-carbon units for essential biosynthetic reactions and for writing epigenetics marks. The leading role in this hub is performed by the one-carbon carrier tetrahydrofolate (THF), which accepts formaldehyde usually from serine generating one-carbon THF intermediates in a set of reactions known as the folate or one-carbon cycle. THF derivatives can feed one-carbon units into purine and thymidine synthesis, and into the methionine cycle that produces the universal methyl-donor S-adenosylmethionine (AdoMet). AdoMet delivers methyl groups for epigenetic methylations and it is metabolized to homocysteine (Hcy), which can enter the transsulfuration pathway for the production of cysteine and lastly glutathione (GSH), the main cellular antioxidant. This vital role of THF comes to an expense. THF and other folate derivatives are susceptible to oxidative breakdown releasing formaldehyde, which can damage DNA -a consequence prevented by the Fanconi Anaemia DNA repair pathway. Epigenetic demethylations catalysed by lysine-specific demethylases (LSD) and Jumonji histone demethylases can also release formaldehyde, constituting a potential threat for genome integrity. In mammals, the toxicity of formaldehyde is limited by a metabolic route centred on the enzyme alcohol dehydrogenase 5 (ADH5/GSNOR), which oxidizes formaldehyde conjugated to GSH, lastly generating formate. Remarkably, this formate can be a significant source of one-carbon units, thus defining a formaldehyde cycle that likely restricts the toxicity of one-carbon metabolism and epigenetic demethylations. This work describes recent advances in one-carbon metabolism and epigenetics, focusing on the steps that involve formaldehyde flux and that might lead to cytotoxicity affecting human health.

Methylenetetrahydrofolate Reductase (MTHFR) Gene Polymorphism and Infant's Anthropometry at Birth

Identification of causal factors that influence fetal growth and anthropometry at birth is of great importance as they provide information about increased risk of disease throughout life. The association between maternal genetic polymorphism MTHFR(677)C>T and anthropometry at birth has been widely studied because of its key role in the one-carbon cycle. MTHFR(677) CT and TT genotypes have been associated with a greater risk of low birth weight, especially in case of deficient intake of folic acid during pregnancy. This study aimed to analyze the association between the maternal MTHFR(677)C>T genetic polymorphism and anthropometry at birth in a population with adequate folate consumption. We included 694 mother-newborn pairs from a prospective population-based birth cohort in Spain, in the Genetics, Early life enviroNmental Exposures and Infant Development in Andalusia (GENEIDA) project. Women were genotyped for MTHFR(677)C>T SNP by Q-PCR using TaqMan© probes. Relevant maternal and newborn information was obtained from structured questionnaires and medical records. Results showed that maternal MTHFR(677)C>T genotype was associated with newborn anthropometry. Genotypes CT or CT/TT showed statistically significant associations with increased or decreased risk of large-for-gestational-age (LGA) or small-for-gestational-age (SGA) based on weight and height, depending on the newborn's sex, as well as with SGA in premature neonates. The relationships between this maternal genotype and anthropometry at birth remained despite an adequate maternal folate intake.

LncRNA-mRNA Expression Profiles and Functional Networks Associated with Cognitive Impairment in Folate-deficient Mice

BACKGROUND

Cognitive impairment is a common neurocognitive disorder that affects millions of worldwide people's health,related tofolate deficiency.

OBJECTIVE

The present study aimed to investigate the lncRNA-mRNA functional networks associated with cognitive impairment in folate-deficient mice and elucidate their possible molecular mechanisms.

METHODS

We downloaded the gene expression profile (GSE148126) of lncRNAs and mRNAs from NCBI Gene Expression Omnibus (GEO) database. Four groups of mouse hippocampi were analyzed, including 4 months (4mo) and 18 months (18mo) of folic acid (FA) deficiency/supplementation. The differentially expressed lncRNAs (DElncRNAs) and mRNAs (DEmRNAs) were identified using gplots and heatmap packages. The functions of the DEmRNAs were evaluated using Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses. The hub genes wereidentified by CytoHubba plugins of Cytoscape, and protein-protein interaction (PPI) network of deregulated mRNAs was performed using STRING database. Finally, lncRNA-mRNA co-expression and competitive endogenous RNA (ceRNA) network analyses were constructed.

RESULTS

In total, we screened 67 lncRNAs with 211 mRNAs, and 89 lncRNAs with 229 mRNAs were differentially expressed in 4mo_FAand 18mo_FA deficient mice, respectively. GO analyses indicated that DEmRNAs were highly related to terms involved in binding and biological regulation. KEGG pathway analyses demonstrated that these genes were significantly enriched for Renin secretion, Pancreatic secretion and AMPK signaling pathways in 18mo_FA deficiency group. Subsequently, the top 5 hub genes werescreened from the PPI network, which may be key genes with the progression of folate deficiency. Upon the lncRNA-mRNA co-expression network analysis, we identified the top 10 lncRNAs having the maximum number of connections with related mRNAs. Finally, a ceRNA network was constructed for DE lncRNAs and DEmRNAs, and several pivotal miRNAs were predicted.

CONCLUSIONS

This study identified the lncRNA-mRNA expression profiles and functional networks associated with cognitive impairment in folate-deficient mice, which provided support for the possible mechanisms and therapy for this disease.

Effect of folic acid on animal models, cell cultures, and human oral clefts: a literature review

Background

Folate is a naturally occurring, water-soluble B vitamin. The synthetic form of this compound is folic acid (FA), the deficiency of which is linked to neural tube disorders (NTD), which can be prevented by consuming it before, or during the early months of, pregnancy. However, the effect of FA on oral cleft formation remains controversial. The aim of the present study was to review the evidence concerning the effect of FA on the formation of cleft lip and palate (CLP) in both animals and humans, as well as its impact on different cell types. A search was conducted on various databases, including MEDLINE, EMBASE, and Central, for articles published until January 2020.

Main body

Current systematic reviews indicate that FA, alone or in combination with other vitamins, prevents NTD; however, there is no consensus on whether its consumption can prevent CLP formation. Conversely, the protective effect of FA on palatal cleft (CP) induction has been inferred from animal models; additionally, in vitro studies enumerate a cell-type and dose-dependent effect of FA on cell viability, proliferation, and differentiation, hence bolstering evidence from epidemiological studies.

Conclusions

Meta-analysis, animal models, and in vitro studies demonstrated the protective effect of FA against isolated CP; however, the heterogeneity of treatment protocols, doses, and FA administration method, as well as the different cell types used in in vitro studies, does not conclusively establish whether FA prevents CLP formation.

Ecology, Phylogeny, and Potential Nutritional and Medicinal Value of a Rare White “Maitake” Collected in a Mediterranean Forest

Albino Grifola frondosa (Dicks.) Gray “maitake” mushrooms (described as G. albicans Imazeki and then placed in synonymy with G. frondosa) are particularly rare, and the few pertinent records are not treated in scientific publications. A field investigation carried out in Sicily (Italy) led to the collection of an unusual white Grifola specimen at the base of a living tree of Quercus pubescens Willd. s.l. The outcome of sequencing the internal transcribed spacer (ITS) region of nuclear ribosomal DNA (nrDNA) indicated that it belongs to G. frondosa and provided an insight to the phylogenetic relationships within the genus. The results of nutritional composition analysis showed that the albino basidioma possesses relatively high contents of Ca, Fe, K, and Cu and is rather low in Na when compared with literature data on edible mushrooms. Vitamin (B1, B2, B3, B5, B9, and D2) contents ranged from 0.15 to 3.89 mg per 100 g of mushroom dry weight. The cold-water extract of this specimen was effective at inhibiting the growth of Staphylococcus epidermidis ATCC 12228 and Pseudomonas aeruginosa ATCC 15442 at the maximum screening concentration of 50% v/v. In addition, the extract slowed down the ability of Staphylococcus aureus ATCC 43300 to form biofilms. According to data hereby reported, the albino G. frondosa is a culinary-medicinal mushroom with a promising exploitation potential.

Folic Acid Supplement Intake and Risk of Colorectal Cancer in Women; A Case Control Study

Background

An ongoing controversy exists on the role of folic acid supplementation in colorectal cancer risk among epidemiological studies.

Objective

To assess the association between maternal folic acid supplementation and colorectal cancer risk.

Methods

A paired matched case control study of 405 subjects was performed, including women residing in 135 villages of East Azerbaijan, Iran. Per area, subjects were followed regularly in local healthcare centers, where health- and social-related information have been collected prospectively in face to face interviews by well-trained health workers. We extracted folic acid supplement intake, baseline characteristics, and confounders from healthcare records. The data for study participants were linked to national cancer registry repositories, from which we retrieved the data of 135 women diagnosed with colorectal cancer between 2005 to 2015. Two hundred seventy controls were individually matched with cases in terms of residing village, age, and gender. We applied multivariate conditional logistic regression to estimate odds ratios (ORs) and 95% confidence intervals (CIs).

Findings

There was no significant association between folic acid supplementation and colorectal cancer risk in those with history of folic acid intake compared to those with no history of intake (OR 0.95; 95% CI 0.59 to 1.53), in those with less than five years of folic acid (0.79; 0.45 to 1.39) or in those with ≥5 years intake (1.09; 0.52 to 2.26). This risk did not change after adjustment for covariates or further stratification.

Conclusions

Maternal folic acid supplementation did not affect colorectal cancer risk in a population where supplemental folic acid is prescribed with regular intervals for women of child-bearing age.

Epigenetic Mechanisms of Maternal Dietary Protein and Amino Acids Affecting Growth and Development of Offspring

Nutrients can regulate metabolic activities of living organisms through epigenetic mechanisms, including DNA methylation, histone modification, and RNA regulation. Since the nutrients required for early embryos and postpartum lactation are derived in whole or in part from maternal and lactating nutrition, the maternal nutritional level affects the growth and development of fetus and creates a profound relationship between disease development and early environmental exposure in the offspring's later life. Protein is one of the most important biological macromolecules, involved in almost every process of life, such as information transmission, energy processing and material metabolism. Maternal protein intake levels may affect the integrity of the fetal genome and alter DNA methylation and gene expression. Most amino acids are supplied to the fetus from the maternal circulation through active transport of placenta. Some amino acids, such as methionine, as dietary methyl donor, play an important role in DNA methylation and body's one-carbon metabolism. The purpose of this review is to describe effects of maternal dietary protein and amino acid intake on fetal and neonatal growth and development through epigenetic mechanisms, with examples in humans and animals.

Evaluation of folate concentration in amniotic fluid and maternal and umbilical cord blood during labor

INTRODUCTION

Folate is required for fetal, placental and maternal tissue growth during pregnancy. A decline in maternal circulating folate concentrations and an increase in total homocysteine (a non-specific indicator of folate deficiency) have been observed with the progression of pregnancy. However, the role of folate in the third trimester of pregnancy is not clear and folate status in late pregnancy has not so far been widely analyzed. The main aim of this retrospective cross-sectional study was to determine the folate concentrations in amniotic fluid and in maternal and umbilical cord blood serum derived during delivery.

MATERIAL AND METHODS

This study was conducted on 175 pregnant Polish women (white/Caucasian) aged between 17 and 42 years. Only pregnancies without birth defects were included in this study. Amniotic fluid, maternal serum, and umbilical cord blood samples were collected during vaginal delivery or cesarean section. Folate concentration was determined using a microbiological assay.

RESULTS

Strong correlations were observed between the concentrations of folate in amniotic fluid and maternal serum (rho = 0.67, p < 0.001) and amniotic fluid and cord blood serum (rho = 0.49, p < 0.001) and between maternal serum and cord blood serum (rho = 0.67, p < 0.001). Folate concentrations in amniotic fluid were significantly associated with maternal age (rho = 0.19, p < 0.05). Pre-pregnancy body mass index and maternal weight/neonatal birth weight ratio were independent predictors of folate concentrations in maternal serum (β = 0.33, p < 0.05; β = -0.19, p < 0.05) and amniotic fluid (β = 0.28, p < 0.05; β = -0.19, p < 0.05) in late pregnancy.

CONCLUSIONS

Folate concentrations in amniotic fluid are associated with maternal and neonatal folate status peripartum in healthy women.

A novel zebrafish model to emulate lung injury by folate deficiency-induced swim bladder defectiveness and protease/antiprotease expression imbalance

Lung injury is one of the pathological hallmarks of most respiratory tract diseases including asthma, acute respiratory distress syndrome (ARDS) and chronic obstructive pulmonary disease (COPD). It involves progressive pulmonary tissue damages which are usually irreversible and incurable. Therefore, strategies to facilitate drug development against lung injury are needed. Here, we characterized the zebrafish folate-deficiency (FD) transgenic line that lacks a fully-developed swim bladder. Whole-mount in-situ hybridization revealed comparable distribution patterns of swim bladder tissue markers between wild-type and FD larvae, suggesting a proper development of swim bladder in early embryonic stages. Unexpectedly, neutrophils infiltration was not observed in the defective swim bladder. Microarray analysis revealed a significant increase and decrease of the transcripts for cathepsin L and a cystatin B (CSTB)-like (zCSTB-like) proteins, respectively, in FD larvae. The distribution of cathepsin L and the zCSTB-like transcripts was spatio-temporally specific in developing wild-type embryos and, in appropriate measure, correlated with their potential roles in maintaining swim bladder integrity. Supplementing with 5-formyltetrahydrofolate successfully prevented the swim bladder anomaly and the imbalanced expression of cathepsin L and the zCSTB-like protein induced by folate deficiency. Injecting the purified recombinant zebrafish zCSTB-like protein alleviated FD-induced swim bladder anomaly. We concluded that the imbalanced expression of cathepsin L and the zCSTB-like protein contributed to the swim bladder malformation induced by FD and suggested the potential application of this transgenic line to model the lung injury and ECM remodeling associated with protease/protease inhibitor imbalance.

The Protective Effect of Maternal Folic Acid Supplementation on Childhood Cancer: A Systematic Review and Meta-analysis of Case-control Studies

OBJECTIVES

Maternal folic acid supplementation is considered mandatory in almost every country in the world to prevent congenital malformations. However, little is known about the association of maternal folic acid intake with the occurrence of childhood cancer. Hence, this study aimed to determine the effects of maternal folic acid consumption on the risk of childhood cancer.

METHODS

A total of 158 related articles were obtained from PubMed, Google Scholar, Scopus, and ProQuest using standardized keywords, of which 17 were included in the final review.

RESULTS

Eleven of the 17 articles showed a significant protective association between maternal folic acid supplementation and childhood cancer. Using a random-effects model, pooled odds ratios (ORs) showed a protective association between maternal folic acid supplementation and childhood acute lymphoblastic leukaemia (OR, 0.75; 95% confidence interval [CI], 0.66 to 0.86). However, there was no significant association between maternal folic acid supplementation and acute myeloid leukaemia (OR, 0.70; 95% CI, 0.46 to 1.06) or childhood brain tumours (OR, 1.02; 95% CI, 0.88 to 1.19).

CONCLUSIONS

Maternal folic acid supplementation was found to have a protective effect against childhood acute lymphoblastic leukaemia. Thus, healthcare professionals are recommended to provide regular health education and health promotion to the community on the benefits of folic acid supplementation during pregnancy.

Association of maternal folate intake during pregnancy with infant asthma risk

Several studies assessed the association of maternal folate intake with infant asthma risk, but the findings are controversial. We performed a meta-analysis to clarify the association between maternal folate intake and infant asthma risk. PubMed and SCOPUS databases were searched for related studies published until August 2018. Fixed-effects models were applied to pool relative risks (RRs) and their corresponding 95% confidence intervals (CIs) due to the low heterogeneity. We also adopted generalized least-squares trend (GLST) estimation for the dose-response analysis. In our study, a total of 10 studies with maternal folate intake and 5 studies with blood folate concentration were included. We found that maternal folate intake during pregnancy was significantly related to the risk of infant asthma (RR = 1.11; 95% CI = 1.06-1.17). Similar results were found for geographic region from Europe (RR = 1.08; 95% CI = 1.01-1.16) and North America (RR = 1.20; 95% CI = 1.11-1.30) in subgroup analyses. Meanwhile, the dose-response analysis showed a linear relationship between maternal folic acid intake during pregnancy and infant asthma risk. This meta-analysis indicates that maternal folate intake during pregnancy could increase infant asthma risk. Therefore, the adverse effect of folic acid on infant asthma should not be ignored when it is supplemented during pregnancy to prevent birth defects.

Does the father matter? The association between the periconceptional paternal folate status and embryonic growth

OBJECTIVE

To study the association between periconceptional paternal folate status and embryonic growth trajectories in early pregnancy.

DESIGN

Prospective periconceptional cohort study.

SETTING

Single tertiary hospital.

PATIENT(S)

A total of 511 singleton pregnancies, with 303 conceived spontaneously and 208 after in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) treatment.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Crown-rump length (CRL) and embryonic volume (EV) at 7, 9, and 11 weeks of gestation measured offline using three-dimensional ultrasound data and a virtual reality system.

RESULT(S)

Using the third quartile of paternal red blood cell (RBC) folate levels as reference values, we found statistically significantly negative associations between RBC folate and longitudinal CRL measurements in the second quartile (beta: -0.14 √mm [95% confidence interval (CI), -0.28 to -0.006]) and fourth quartile (beta: -0.19 √mm [95% CI, -0.33 to -0.04]) in spontaneously conceived pregnancies. Comparable results were found for longitudinal EV measurements in the fourth quartile (beta: -0.12 ∛cm³ [95% CI, -0.20 to -0.05]). No statistically significant associations were observed between RBC folate levels and embryonic growth trajectories in IVF-ICSI pregnancies.

CONCLUSION(S)

These data demonstrate for the first time that low and high periconceptional paternal RBC folate levels are associated with reduced embryonic growth trajectories in spontaneously conceived pregnancies. These data underline the importance of paternal folate status during the periconception period.

Bone Regeneration Induced by Strontium Folate Loaded Biohybrid Scaffolds

Nowadays, regenerative medicine has paid special attention to research (in vitro and in vivo) related to bone regeneration, specifically in the treatment of bone fractures or skeletal defects, which is rising worldwide and is continually demanding new developments in the use of stem cells, growth factors, membranes and scaffolds based on novel nanomaterials, and their applications in patients by using advanced tools from molecular biology and tissue engineering. Strontium (Sr) is an element that has been investigated in recent years for its participation in the process of remodeling and bone formation. Based on these antecedents, this is a review about the Strontium Folate (SrFO), a recently developed non-protein based bone-promoting agent with interest in medical and pharmaceutical fields due to its improved features in comparison to current therapies for bone diseases.

A randomized controlled trial of folic acid intervention in pregnancy highlights a putative methylation-regulated control element at ZFP57

BACKGROUND

Maternal blood folate concentrations during pregnancy have been previously linked with DNA methylation patterns, but this has been done predominantly through observational studies. We showed recently in an epigenetic analysis of the first randomized controlled trial (RCT) of folic acid supplementation specifically in the second and third trimesters (the EpiFASSTT trial) that methylation at some imprinted genes was altered in cord blood samples in response to treatment. Here, we report on epigenome-wide screening using the Illumina EPIC array (~ 850,000 sites) in these same samples (n = 86).

RESULTS

The top-ranked differentially methylated promoter region (DMR) showed a gain in methylation with folic acid (FA) and was located upstream of the imprint regulator ZFP57. Differences in methylation in cord blood between placebo and folic acid treatment groups at this DMR were verified using pyrosequencing. The DMR also gains methylation in maternal blood in response to FA supplementation. We also found evidence of differential methylation at this region in an independent RCT cohort, the AFAST trial. By altering methylation at this region in two model systems in vitro, we further demonstrated that it was associated with ZFP57 transcription levels.

CONCLUSIONS

These results strengthen the link between folic acid supplementation during later pregnancy and epigenetic changes and identify a novel mechanism for regulation of ZFP57. This trial was registered 15 May 2013 at www.isrctn.com as ISRCTN19917787.

Effects of folic acid food fortification scenarios on the folate intake of a multi-ethnic pregnant population

OBJECTIVE

To simulate effects of different scenarios of folic acid fortification of food on dietary folate equivalents (DFE) intake in an ethnically diverse sample of pregnant women.

DESIGN

A forty-four-item FFQ was used to evaluate dietary intake of the population. DFE intakes were estimated for different scenarios of food fortification with folic acid: (i) voluntary fortification; (ii) increased voluntary fortification; (iii) simulated bread mandatory fortification; and (iv) simulated grains-and-rice mandatory fortification.

SETTING

Ethnically and socio-economically diverse cohort of pregnant women in New Zealand.ParticipantsPregnant women (n 5664) whose children were born in 2009-2010.

RESULTS

Participants identified their ethnicity as European (56·0 %), Asian (14·2 %), Māori (13·2 %), Pacific (12·8 %) or Others (3·8 %). Bread, breakfast cereals and yeast spread were main food sources of DFE in the two voluntary fortification scenarios. However, for Asian women, green leafy vegetables, bread and breakfast cereals were main contributors of DFE in these scenarios. In descending order, proportions of different ethnic groups in the lowest tertile of DFE intake for the four fortification scenarios were: Asian (39-60 %), Others (41-44 %), European (31-37 %), Pacific (23-26 %) and Māori (23-27 %). In comparisons within each ethnic group across scenarios of food fortification with folic acid, differences were observed only with DFE intake higher in the simulated grains-and-rice mandatory fortification v. other scenarios.

CONCLUSIONS

If grain and rice fortification with folic acid was mandatory in New Zealand, DFE intakes would be more evenly distributed among pregnant women of different ethnicities, potentially reducing ethnic group differences in risk of lower folate intakes.

Association between one-carbon metabolism indices and DNA methylation status in maternal and cord blood

One-carbon metabolism is essential for multiple cellular processes and can be assessed by the concentration of folate metabolites in the blood. One-carbon metabolites serve as methyl donors that are required for epigenetic regulation. Deficiencies in these metabolites are associated with a variety of poor health outcomes, including adverse pregnancy complications. DNA methylation is known to vary with one-carbon metabolite concentration, and therefore may modulate the risk of adverse pregnancy outcomes. This study addresses changes in one-carbon indices over pregnancy and the relationship between maternal and child DNA methylation and metabolite concentrations by leveraging data from 24 mother-infant dyads. Five of the 13 metabolites measured from maternal blood and methylation levels of 993 CpG sites changed over the course of pregnancy. In dyads, maternal and fetal one-carbon concentrations were highly correlated, both early in pregnancy and at delivery. The 993 CpG sites whose methylation levels changed over pregnancy in maternal blood were also investigated for associations with metabolite concentrations in infant blood at delivery, where five CpG sites were associated with the concentration of at least one metabolite. Identification of CpG sites that change over pregnancy may result in better characterization of genes and pathways involved in maintaining a healthy, term pregnancy.

System biology approach intersecting diet and cell metabolism with pathogenesis of brain disorders

The surge in meals high in calories has prompted an epidemic of metabolic disorders around the world such that the elevated incidence of obese and diabetic individuals is alarming. New research indicates that metabolic disorders pose a risk for neurological and psychiatric conditions including stroke, Alzheimer's disease, Huntington's disease, and depression, all of which have a metabolic component. These relationships are rooted to a dysfunctional interaction between molecular processes that regulate energy metabolism and synaptic plasticity. The strong adaptive force of dietary factors on shaping the brain during evolution can be manipulated to transform the interaction between cell bioenergetics and epigenome with the aptitude to promote long-lasting brain healthiness. A thorough understanding of the association between the broad action of nutrients and brain fitness requires high level data processing empowered with the capacity to integrate information from a multitude of molecular entities and pathways. Nutritional systems biology is emerging as a viable approach to elucidate the multiple molecular layers involved in information processing in cells, tissues, and organ systems in response to diet. Information about the wide range of cellular and molecular interactions elicited by foods on the brain and cognitive plasticity is crucial for the design of public health initiatives for curtailing the epidemic of metabolic and brain disorders.

Maternal folic acid supplementation and antibody persistence 5 years after hepatitis B vaccination among infants

BACKGROUND

Maternal exposure to dietary factors during pregnancy may modulate the immunity of offspring by epigenetic programming. But the relationship between intrauterine environment and persistence of protective antibody after hepatitis B vaccination has not been reported. This study was to investigate the 5-year persistence of protective antibody response after primary hepatitis B vaccination, and its relationship with maternal folic acid supplementation.

MATERIALS AND METHODS

A total of 1461 children who completed a 3-dose 10 μg recombinant hepatitis B vaccine at birth and did not infect hepatitis B virus were followed up. Logistic regression and mediation analysis was used to explore the relationship between 5-year persistence of protective antibody and maternal nutrition.

RESULTS

Of 1403 children who did not revaccinated during the follow-up, 76.1% had protective hepatitis B surface antibody (anti-HBs) levels. Twenty percent of mothers did not take folate during pregnancy. Mediation analysis showed a total effect of folic acid supplementation on good persistence (odds ratio: 1.10, 95% CI: 1.03-1.17, p = 0.0010), a direct effect was 1.07 (95% CI: 1.01-1.13, p = 0.0128) and an indirect effect was 1.03 (95% CI: 1.00-1.06, p = 0.0672); the proportion of good persistence mediated by primary response was 30.3%.

CONCLUSION

This study indicated a good protective anti-HBs persistence at year 5 after 10 μg recombination hepatitis B vaccination in infants. Maternal folic acid supplementation may improve the persistence of protective antibodies through other pathways. Multi-center cohort studies should be conducted to verify this conclusion.

Trimester-Specific Dietary Intakes in a Sample of French-Canadian Pregnant Women in Comparison with National Nutritional Guidelines

Diet during pregnancy greatly impacts health outcomes. This study aims to measure changes in dietary intakes throughout trimesters and to assess pregnant women’s dietary intakes in comparison with current Canadian nutritional recommendations. Seventy-nine pregnant women were recruited and completed, within each trimester, three Web-based 24-h dietary recalls and one Web questionnaire on supplement use. Dietary intakes from food, with and without supplements, were compared to nutritional recommendations throughout pregnancy. Energy and macronutrient intakes remained stable throughout pregnancy. A majority of women exceeded their energy and protein requirements in the first trimester, and fat intakes as a percentage of energy intakes were above recommendations for more than half of the women in all trimesters. Supplement use increased dietary intakes of most vitamins and minerals, but 20% of women still had inadequate total vitamin D intakes and most women had excessive folic acid intakes. This study showed that pregnant women did not increase their energy intakes throughout pregnancy as recommended. Furthermore, although prenatal supplementation reduces the risk of inadequate intake for most micronutrients, there is still a risk of excessive folic acid and insufficient vitamin D intake, which needs further investigation.

The long-term impact of folic acid in pregnancy on offspring DNA methylation: follow-up of the Aberdeen Folic Acid Supplementation Trial (AFAST)

BACKGROUND

It has been proposed that maternal folic-acid supplement use may alter the DNA-methylation patterns of the offspring during the in-utero period, which could influence development and later-life health outcomes. Evidence from human studies suggests a role for prenatal folate levels in influencing DNA methylation in early life, but this has not been extended to consider persistent effects into adulthood.

METHODS

To better elucidate the long-term impact of maternal folic acid in pregnancy on DNA methylation in offspring, we carried out an epigenome-wide association study (EWAS) nested within the Aberdeen Folic Acid Supplementation Trial (AFAST-a trial of two different doses: 0.2 and 5 mg, folic acid vs placebo). Offspring of the AFAST participants were recruited at a mean age of 47 years and saliva samples were profiled on the Illumina Infinium Human Methylation450 array. Both single-site and differentially methylated region analyses were performed.

RESULTS

We found an association at cg09112514 (p = 4.03×10-9), a CpG located in the 5' untranslated region of PDGFRA, in the main analysis comparing the intervention arms [low- (0.2 mg) and high-dose (5 mg) folic acid combined (N = 43)] vs placebo (N = 43). Furthermore, a dose-response reduction in methylation at this site was identified in relation to the intervention. In the regional approach, we identified 46 regions of the genome that were differentially methylated in response to the intervention (Sidak p-value <0.05), including HLA-DPB2, HLA-DPB1, PAX8 and VTRNA2-1. Whereas cg09112514 did not replicate in an independent EWAS of maternal plasma folate, there was suggested replication of differential methylation in PAX8.

CONCLUSIONS

The results of this study suggest that maternal folic-acid supplement use is associated with changes in the DNA methylation of the offspring that persist for many years after exposure in utero. These methylation changes are located in genes implicated in embryonic development, immune response and cellular proliferation. Further work to investigate whether these epigenetic changes translate into detectable phenotypic differences is required.

One crisis, diverse impacts-Tissue-specificity of folate deficiency-induced circulation defects in zebrafish larvae

Folate (vitamin B9) is an essential nutrient required for cell survival, proliferation, differentiation and therefore embryogenesis. Folate deficiency has been associated with many diseases, including congenital heart diseases and megaloblastic anemia, yet the mechanisms underlying these remains elusive. Here, we examine the impact of folate deficiency on the development of the circulation system using a zebrafish transgenic line which displays inducible folate deficiency. Impaired hematopoiesis includes decreased hemoglobin levels, decreased erythrocyte number, increased erythrocyte size and aberrant c-myb expression pattern were observed in folate deficient embryos. Cardiac defects, including smaller chamber size, aberrant cardiac function and cmlc2 expression pattern, were also apparent in folate deficient embryos. Characterization of intracellular folate content in folate deficiency revealed a differential fluctuation among the different folate derivatives that carry a single carbon group at different oxidation levels. Rescue attempts by folic acid and nucleotides resulted in differential responses among affected tissues, suggesting that different pathomechanisms are involved in folate deficiency-induced anomalies in a tissue-specific manner. The results of the current study provide an explanation for the inconsistent outcome observed clinically in patients suffering from folate deficiency and/or receiving folate supplementation. This study also supports the use of this model for further research on the defective cardiogenesis and hematopoiesis caused by folate deficiency.

Dietary metabolites derived from gut microbiota: critical modulators of epigenetic changes in mammals

The mammalian gastrointestinal tract harbors trillions of commensal microorganisms, collectively known as the microbiota. The microbiota is a critical source of environmental stimuli and, thus, has a tremendous impact on the health of the host. The microbes within the microbiota regulate homeostasis within the gut, and any alteration in their composition can lead to disorders that include inflammatory bowel disease, allergy, autoimmune disease, diabetes, mental disorders, and cancer. Hence, restoration of the gut flora following changes or imbalance is imperative for the host. The low-molecular-weight compounds and nutrients such as short-chain fatty acids, polyamines, polyphenols, and vitamins produced by microbial metabolism of nondigestible food components in the gut actively participate in various epigenomic mechanisms that reprogram the genome by altering the transcriptional machinery of a cell in response to environmental stimuli. These epigenetic modifications are caused by a set of highly dynamic enzymes, notably histone acetylases, deacetylases, DNA methylases, and demethylases, that are influenced by microbial metabolites and other environmental cues. Recent studies have shown that host expression of histone acetylases and histone deacetylases is important for regulating communication between the intestinal microbiota and the host cells. Histone acetylases and deacetylases influence the molecular expression of genes that affect not only physiological functions but also behavioral shifts that occur via neuroepigenetic modifications of genes. The underlying molecular mechanisms, however, have yet to be fully elucidated and thus provide a new area of research. The present review provides insights into the current understanding of the microbiota and its association with mammalian epigenomics as well as the interaction of pathogens and probiotics with host epigenetic machinery.

Folic acid intake and folate status and colorectal cancer risk: A systematic review and meta-analysis

BACKGROUND & AIMS

To evaluate the controversies among the studies assessing the association between folic acid intake or folate status and colorectal cancer risk.

METHODS

PubMed, Cochrane library and references of related articles were searched from January 2000 to September 2016. Studies on folic acid intake or folate status and colorectal cancer or adenoma risk were included. Full text review was conducted for potentially eligible studies. Quality assessment was performed. Random-effects meta-analysis was used to estimate risk ratio and 95% Confidence Intervals. Analysis was conducted by Comprehensive Meta-Analysis software.

RESULTS

Folic acid supplement intake showed no significant effect on colorectal cancer risk in meta-analysis of randomized controlled trials, RR: 1.07 (95% CI: 0.86-1.43). The effect on risk was not significant in cohort studies either; RR = 0.96 (95% CI: 0.76-1.21). However, there was significant reduced colorectal cancer risk in total folate intake in cohort studies; 0.71 (95% CI: 0.59-0.86). Odds Ratio was also significantly reduced in case control studies; 0.77 (95% CI: 0.62-0.95). Nevertheless once folate status was measured as Red Blood Cell folate content, no significant effect on colorectal cancer risk was observed; 1.05 (95% CI: 0.85-1.30).

CONCLUSION

The differences in bioavailability and metabolism of synthetic folic acid and natural dietary folate as well as variation in the baseline characteristics of subjects and various methods of folate status assessment might be the main reasons for these controversies. Findings of present study highlight the importance of individualized folic acid supplement intake given the fact that the beneficiary effects of long term folic acid supplementation is not confirmed.

Association between Serum Unmetabolized Folic Acid Concentrations and Folic Acid from Fortified Foods

OBJECTIVE

To investigate the association between serum unmetabolized folic acid (UMFA) concentrations and folic acid from fortified foods and nutrients known as dietary methyl-group donors (folate, methionine, choline, betaine and vitamins B2, B6 and B12) in participants exposed to mandatory fortification of wheat and maize flours with folic acid.

METHODS

Cross-sectional study carried out with 144 healthy Brazilian participants, both sexes, supplement nonusers. Serum folate, UMFA, vitamin B12 and total plasma homocysteine (tHcy) were biochemically measured. Dietary intake was assessed by 2 non-consecutive 24-hour dietary recalls (24-HRs) and deattenuated energy-adjusted nutrient data were used for statistical analysis.

RESULTS

Ninety eight (68.1%) participants were women. Median (interquartile range) age was 35.5 (28.0-52.0) years. Elevated serum folate concentrations (>45 nmol/L) were found in 17 (11.8%), while folate deficiency (<7 nmol/L) in 10 (6.9%) participants. No one had vitamin B12 deficiency (<148 pmol/L). An elevated serum UMFA concentration was defined as > 1 nmol/L (90th percentile). UMFA concentrations were positively correlated with folic acid intake and negatively correlated to choline, methionine and vitamin B6 intakes. Participants in the lowest quartile of UMFA concentrations had lower dietary intake of total folate (DFEs) and folic acid, and higher dietary intake of methionine, choline and vitamin B6 than participants in the highest quartile of UMFA. Folic acid intake (OR [95% CI] = 1.02 [1.01-1.04)] and being a male (OR [95% CI] = 0.40 [0.19-0.87) were associated with increased and reduced odds for UMFA concentrations > 0.55 nmol/L (median values), respectively.

CONCLUSION

UMFA concentrations were directly influenced by folic acid intake from fortified foods in a healthy convenience sample of adult Brazilians exposed to mandatory flour fortification with folic acid.

Folate dietary insufficiency and folic acid supplementation similarly impair metabolism and compromise hematopoiesis

While dietary folate deficiency is associated with increased risk for birth defects and other diseases, evidence suggests that supplementation with folic acid can contribute to predisposition to some diseases, including immune dysfunction and cancer. Herein, we show that diets supplemented with folic acid both below and above the recommended levels led to significantly altered metabolism in multiple tissues in mice. Surprisingly, both low and excessive dietary folate induced similar metabolic changes, which were particularly evident for nucleotide biosynthetic pathways in B-progenitor cells. Diet-induced metabolic changes in these cells partially phenocopied those observed in mice treated with anti-folate drugs, suggesting that both deficiency and excessive levels of dietary folic acid compromise folate-dependent biosynthetic pathways. Both folate deficiency and excessive dietary folate levels compromise hematopoiesis, resulting in defective cell cycle progression, persistent DNA damage, and impaired production of lymphocytes. These defects reduce the reconstitution potential in transplantation settings and increase radiation-induced mortality. We conclude that excessive folic acid supplementation can metabolically mimic dietary folate insufficiency, leading to similar functional impairment of hematopoiesis.