Dietary Folate Research Articles

Serum folate levels, but not vitamin B12, are associated with slower progression in carotid intima-media thickness in a population exposed to mandatory folic acid fortification

Background&AimsFolate and vitamin B12 are vitamins involved in one carbon metabolism. Carotid intima-media thickness (cIMT) is a non-invasive test and an early atherosclerosis marker. The relationship between these vitamins and cIMT is not well established. This study aimed to investigate the association between baseline vitamins and cIMT changes during a median follow-up of 8 years. MethodsProspective cohort study involving 5,061 ELSA-Brasil participants from São Paulo state aged 35-74 years at baseline. Serum folate and vitamin B12 levels and dietary intake were assessed at baseline. Ultrasound cIMT measurements were performed at baseline and wave 3. Linear mixed-effects models, adjusted for covariables, assessed the association between vitamins at baseline and changes in cIMT. Results4,260 participants were included; mean (SD) age was 51.4 (8.9) years and 54.5% were women. Folate (0.02%) and vitamin B12 (2.6%) deficiencies were almost nonexistent. Participants in the 4th quartile of serum folate had a slower cIMT increase during 8 years of follow-up than those in the 1st quartile (1st vs. 4th quartile comparison: β (95% CI): -0.015 (-0.026; -0.004), P: 0.006 for model 3). These findings remained the same after sensitivity analysis for overall dietary supplements and specifically multivitamins use. No association was found between vitamin B12 biomarker and the outcome. Dietary folate intake was also not associated with cIMT changes. ConclusionIn this population exposed to mandatory folic acid food fortification, prevalence of vitamins deficiencies was very low. Highest quartile of serum folate seemed to slow down the increment of cIMT measurements over time.

Association between dietary folate intake and severe headache or migraine in adults: a cross-sectional study of the National Health and Nutrition Examination Survey

BackgroundThe aim of this study was to assess the association between dietary folate intake and severe headache or migraine.MethodsThis cross-sectional study utilized the National Health and Nutrition Examination Survey (NHANES) data from 1999 to 2004. Weighted logistic regression models, restricted cubic spline (RCS) regression, sensitivity analysis, and stratified analyses were performed to evaluate the association between dietary folate intake and severe headache or migraine.ResultsA total of 4,107 participants were included, with 704 individuals (17.14%) experienced severe headache or migraine. After adjusting for all covariates, an independent association was found between dietary folate intake and severe headache or migraine (OR = 0.77, 95% CI: 0.64–0.93, p = 0.005). When folate intake was categorized, individuals in Q2 (251.21–356.00 μg/d), Q3 (356.19–514.00 μg/d), and Q4 (≥515.00 μg/d) had ORs of 0.95 (95% CI: 0.75–1.20, p = 0.660), 0.86 (95% CI: 0.67–1.12, p = 0.266), and 0.65 (95% CI: 0.48–0.89, p = 0.007), respectively, compared to those in Q1 (≤251.00 μg/d). The RCS regression showed a linear negative relationship between dietary folate intake and severe headache or migraine. Stratified and sensitivity analyses yielded similar results.ConclusionThere was a linear negative relationship between dietary folate intake and migraine.

Effect of school feeding program on dietary folate intake among school adolescent girls in Sidama region, southern Ethiopia.

Ethiopia recently initiated a school feeding program (SFP) that provides nutritious meals to vulnerable students during school to combat malnutrition and improve their nutrition. However, there is limited evidence regarding the program's impact on dietary folate intake among adolescent girls. Improving folate status in adolescent girls is important to prevent neural tube defect and anemia This study was aimed at assessing the effect of the SFP on dietary folate intake among school adolescent girls in the Sidama Region, Southern Ethiopia. This school-based cross-sectional study compared dietary folate intake among adolescent girls enrolled in schools with (n = 290) and without (n = 290) SFP. Multistage sampling method was used to select adolescent girls from 12 schools. The multiple pass 24-h dietary recall method was used to estimate the dietary intake of adolescent girls. Dietary diversity in the preceding day of the survey was assessed with the standard nine-food group score. Nutrient inadequacy was defined as a proportion of adolescents with dietary value of nutrient intake less than the recommended daily allowance (RDA). The dietary folate intake was compared between two groups using multilevel mixed effects linear regression model adjusted for potential confounders. The result showed significantly higher mean (±SD) dietary folate intake in SFP beneficiaries (421.12 ± 78.60 μg/day) than the non-beneficiaries (393.26 ± 74.57 μg/day; β = 27.19, p < 0.001). SFP beneficiary girls had a significantly higher mean (±SD) dietary diversity score (5.24 ± 1.35) compared to non-beneficiary girls (4.83 ± 1.54; β = 0.40, p = 0.001). The prevalence of inadequate folate intake was significantly higher among no-beneficiaries (47.4%) compared to beneficiaries (36.9%; p = 0.01). The SFP in Sidama region improved folate intake and dietary diversity of adolescent girls. The evidence from this study supports the expansion of the program to enhance dietary intake of nutrients of adolescent girls in the region.

Associations of polycyclic aromatic hydrocarbons exposure with mortality and effect modification by folate biomarkers in a prospective population

The associations of folate biomarkers and polycyclic aromatic hydrocarbons (PAHs) in the general population remain unclear. Therefore, this study aimed to examine whether folate biomarkers are associated with PAHs, and whether folate biomarkers can mitigate adverse health outcome caused by PAHs. This prospective cohort study included 11,246 participants from the National Health and Nutrition Examination Survey (NHANES), which documented 1,303 deaths over a mean follow-up of 9.1 years. Multivariable linear regression models were used to examine the relationship between urinary individual PAHs and folate biomarkers. Multivariable Cox proportional hazards regression models were used to calculate hazard ratios and 95 % CIs for the associations of PAHs and folate biomarkers with CVDs mortality and all-cause mortality. We found negative associations between folate in red blood cells (RBC) and urinary 1-Hydroxyphenanthrene (percentage change for a 2·7 fold-increase in folate −4.19 %, 95 % CI -5.80 % to −2.56 %CI), 2-Hydroxyfluorene (−6.66 %, −7.84 % to −5.49 %), 3-Hydroxyfluorene (−5.78 %, −6.77 % to −4.78 %)) and 1-Hydroxynapthalene (−2.75 %, −3.48 % to −2.01 %). The associations between serum folate and PAHs were consistent with those observed for RBC folate, and negative associations were also found between serum folate and 2-Hydroxynapthalene (−4.10 %, −5.26 % to −2.94 %). Within the lowest quartile of folate levels in RBC, there are strong associations of 2-Hydroxyfluorene, 3-Hydroxyfluorene, 1-Hydroxynapthalene, and 2-Hydroxynapthalene with elevated risk of CVDs mortality [HRs (95 % CI) >1]. As folate levels in RBC increase to the third and fourth quartiles, these associations no longer exist [HRs (95 % CI) <1, P-interaction<0.05]. The positive associations between urinary PAHs and CVDs mortality are also eliminated as serum folate levels rise [HRs (95 % CI) <1, P-interaction<0.05]. Furthermore, we also found higher levels of folate in both RBC and serum can greatly reduce the adverse impact of 1-Hydroxynapthalene on all-cause mortality. Consistent results were also validated in daily dietary folate and the folic acid supplement intake. Our study highlighted a robust negative relationship between urinary PAHs and folate. Additionally, folate was found to effectively mitigate mortality caused by PAHs, although we did not observe a direct reduction in mortality attributable to folate.

High penetrance and phenotypic landscape of methylenetetrahydrofolate reductase c.665 C>T polymorphism in the absence of folate fortification

BackgroundStudies have linked the methylenetetrahydrofolate reductase (MTHFR) c.665C>T (rs1801133) with hyperhomocysteinemia. Mandatory folate fortification nullified this association. However, its relevance persists in regions with no folate fortification resulting in a relatively low frequency of this variant in healthy population. This study explored the MTHFR variant’s association with 50 clinical manifestations in the absence of folate fortification. MethodsWe performed mutation analysis via whole exome and Sanger sequencing in 2431 cases and 1265 healthy controls and the food frequency-based dietary folate intake assessment. ResultsThe cohort’s average dietary folate intake was 373 ± 141 μg/day. MTHFR rs1801133 variant demonstrated ≥4.49-fold increased risk for respiratory distress, recurrent pregnancy loss (RPL), ischemic stroke, autism, global developmental delay, dysplasia, myoclonic jerks, intellectual disability, aggressive behavior, motor delay, Alzheimer’s, cerebellar atrophy, failure to thrive, cerebral atrophy, increased tendon reflexes, and spasticity (p<0.0001). MTHFR T-allele showed 1.81 – 4.04 folds increased risk for mental retardation, behavioral problems, dystonia, anemia, gait abnormality, hypotonia, recurrent pneumonia, liver disease, cerebral palsy, short stature, hyperactivity, and cognitive decline. The association of this variant with seizures was moderate (OR: 1.51, 95% CI: 1.13 – 2.02, p=0.009). MTHFR TT-genotype was associated with a 5.81-fold risk for the abnormal phenotype (95% CI: 1.39 – 24.28, p=0.005). MTHFR T-allele was associated with low 25-hydroxy vitamin D, Ferritin, TIBC, and elevated total cholesterol. ConclusionThe MTHFR rs1801133 increases the risk for RPL, developmental milestones, neuronal development, autism, ischemic stroke, and late-onset neurological functions. The MTHFR TT-genotype is strongly associated with abnormal phenotypes.

Response of One-Carbon Biomarkers in Maternal and Cord Blood to Folic Acid Dose During Pregnancy.

The folate Recommended Daily Allowance (RDA) for pregnant women is 600 μg/day dietary folate equivalents, which is equivalent to approximately 400 μg folic acid. Many prenatal supplements contain much higher doses of folic acid. The body's ability to reduce synthetic folic acid to the metabolically active form may be exceeded with high levels of supplementation. The objective of this double-blinded randomized controlled intervention trial was to determine changes in unmetabolized folic acid and other biomarkers of folate and one-carbon metabolism in maternal and cord blood in response to a folic acid dose commonly found in prenatal supplements (800 μg/day) compared to the dose equivalent of the RDA (400 μg/day). Healthy pregnant women were randomized and provided supplements from their first prenatal visit (<12 weeks gestation) through delivery. Maternal blood was collected at baseline and delivery. Umbilical cord blood from the mothers was collected at delivery. A repeated measures analysis of variance revealed that there was a significant group supplemental dose effect (p = 0.0225) on serum unmetabolized folic acid concentration in mothers but no difference in cord blood unmetabolized folic acid concentrations between groups. Mixed effects analysis found a significant overall effect of pre-pregnancy BMI (p = 0.0360) and length of previous folic acid supplementation (p = 0.0281) on serum folate concentrations. No treatment effect was seen in RBC folate concentrations. Choline concentrations were higher in cord blood from the 800 μg/day group compared to the 400 μg/day group, but there was no group effect in maternal choline concentrations. The results indicate that folic acid dose during pregnancy affects certain folate and one-carbon biomarkers, and these effects are not consistent between maternal and cord blood. Potential long-term effects of these results on both mothers and offspring are unknown and merit further investigation.

Association between RBC folate and diabetic nephropathy in Type2 diabetes mellitus patients: a cross-sectional study

Folates play a crucial role as cofactors in metabolic pathways, influencing biological methylation and nucleotide synthesis, which has a significant impact on overall health and disease susceptibility. Diabetic nephropathy (DN) is a prevalent and severe complication of diabetes mellitus (DM). The correlation between RBC folate and DN remains unclear currently. This study aims to assess whether RBC folate is associated with DN. Based on data from the NHANES (2011–2018), we conducted a cross-sectional study involving 3070 adults with type 2 DM (T2DM). Demographic factors, levels of folate and vitamin B12, dietary folate intakes, and relevant laboratory data were obtained from all participants. Logistic regression, fitting smooth curves, interaction effects were utilized to support the research objectives. Regression analyses demonstrated a positive relation between RBC folate and DN. (P < 0.001). A positive association between levels of RBC folate and the risk of DN was observed after full adjustment for all the confounding variables (odds ratio: 1.38, 95% confidence interval: 1.27–1.49, P < 0.001). Similar patterns of association were observed for subgroup analysis (all P values for interaction > 0.05). In addition, curve fitting after adjusting for all the confounding variables demonstrated that there was a linear relationship between RBC folate and DN (P for non-linearity = 0.147). Increased RBC folate levels were linked to a higher risk of DN in type 2 diabetes. RBC folate should be considered as a crucial indicator for folate status in DN.

Folate and cobalamin status, indicators, modulators, interactions, and reference ranges from early pregnancy until birth: the Reus–Tarragona birth cohort study

BackgroundFolate and cobalamin status, although essential for pregnancy, are not routinely monitored in prenatal care. ObjectivesTo investigate folate and cobalamin status and determinants throughout pregnancy, in the absence of mandatory folic acid (FA) fortification. MethodsIn a cohort study of 831 mothers recruited at <12 gestational weeks (GW), plasma folate, total homocysteine (tHcy), cobalamin, holotranscobalamin (holoTC), methylmalonic acid (MMA), red blood cell folate (RBCF), and the combined cobalamin status indicator (cB12) were determined at ≤12, 15, 24–27, 34 GW, labor and in the cord. Single nucleotide polymorphisms affecting folate and cobalamin status were determined. FA, cobalamin, micronutrient supplement use, and dietary folate and cobalamin intake (food frequency questionnaire) were recorded. Folate and cobalamin status predictors were assessed by multiple linear regression analysis. ResultsOnly 36.1% of the participants took FA preconceptionally and 47.4% and 7.3% had suboptimal RBCF (<906 nmol/L) and plasma cobalamin status (≤221 pmol/L), respectively, at ≤12 GW. RBCF determinants included planned pregnancy, FA supplementation, plasma cobalamin, and methylenetetrahydrofolate (MTHFR) 677C>T genotype. Cobalamin supplementation was positively associated with plasma cobalamin and early holoTC. Smoking and BMI were inversely associated with plasma cobalamin and early holoTC, but none were associated with MMA. Only participants with the MTHFR 677TT genotype, exceeding FA supplement recommendations, improved their folate status (interaction term: B (95% CI):0.15 (0.01, 0.29), P = 0.032). Smoking was inversely associated with plasma cobalamin status in participants with the methionine synthase reductase (MTRR) 524CC genotype only (interaction term:0.07 (0.01, 0.04), P = 0.014). Mothers with low early pregnancy cobalamin status and also those with bigger newborns, had lower cobalamin status at labor. ConclusionsSuboptimal early pregnancy folate or cobalamin status affected 47.4% and 7.3% of the participants, respectively. The MTHFR 677TT genotype predicted folate status throughout pregnancy. Smoking and BMI were negatively associated with cobalamin status throughout pregnancy.Clinical Trial Registry number and website where it was obtained: NCT01778205. www.clinicaltrials.gov

Excess Folic Acid Exposure Increases Uracil Misincorporation into DNA in a Tissue-Specific Manner in a Mouse Model of Reduced Methionine Synthase Expression

BackgroundFolate and vitamin B12 (B12) are cofactors in folate-mediated 1-carbon metabolism (FOCM), a metabolic network that supports synthesis of nucleotides (including thymidylate [dTMP]) and methionine. FOCM impairments such as a deficiency or imbalance of cofactors can perturb dTMP synthesis, causing uracil misincorporation into DNA. ObjectiveThe purpose of this study was to determine how reduced expression of the B12-dependent enzyme methionine synthase (MTR) and excess dietary folic acid interact to affect folate distribution and markers of genome stability in mouse tissues. MethodsHeterozygous Mtr knockout mice (Mtr+/–) model the FOCM-specific effects of B12 deficiency. Folate accumulation and vitamer distribution, genomic uracil concentrations, and phosphorylated histone H2AX (γH2AX) immunostaining were measured in male Mtr+/+ and Mtr+/− mice weaned to either a folate-sufficient control (C) diet (2 mg/kg folic acid) or a high folic acid (HFA) diet (20 mg/kg folic acid) for 7 wk. ResultsExposure to the HFA diet led to tissue-specific patterns of folate accumulation, with plasma, colon, kidney, and skeletal muscle exhibiting increased folate concentrations compared with control. Liver total folate did not differ. Although unmetabolized folic acid (UMFA) increased 10-fold in mouse plasma with HFA diet, UMFA accounted for <0.2% of total folate in liver and colon tissue. Exposure to HFA diet resulted in a shift in folate distribution in colon tissue with higher 5-methyl-THF and lower formyl-THF than in control mice. Mtr heterozygosity did not impact folate accumulation or distribution in any tissue. Mice on HFA diet exhibited higher uracil in genomic DNA and γH2AX foci in colon. Similar differences were not seen in liver. ConclusionsThis study demonstrates that folic acid, even when consumed at high doses, does not meaningfully accumulate in mouse tissues, although high-dose folic acid shifts folate distribution and increases uracil accumulation in genomic DNA in colon tissue.

Causal relationship between folic acid and prostate cancer risk: Insights from Mendelian randomization analysis.

Folic acid is a commonly used dietary supplement of trace element, but it may increase the risk of prostate cancer (PCa). The aim of this study was to investigate the causal relationship between PCa and folic acid supplementation, as well as dietary folate equivalents, using Mendelian randomization (MR) analysis. The Genome-Wide Association Study (GWAS) data of folic acid supplementation and dietary folate equivalents were selected from UK Biobank. Meta-analysis of GWASs of PCa was obtained from PCa Association Group to Investigate Cancer-Associated Alterations in the Genome consortium. MR analysis was performed with inverse variance weighted (IVW) method, MR-Egger regression, simple mode, weighted median, and weighted mode analysis. Heterogeneity and horizontal pleiotropy tests and reverse MR analysis were conducted to assess the robustness and reliability of the causal inference. Six single nucleotide polymorphisms (SNPs) associated with folic acid supplementation and five SNPs associated with dietary folate equivalents were identified as instrumental variables. Genetically predicted folic acid supplementation was associated with an increased risk of PCa (OR 1.200, p < 0.001, by IVW method), and there was no evidence of heterogeneity, horizontal pleiotropy, or significant reverse causality (all p > 0.05). In contrast, dietary folate equivalents showed no significant correlation with PCa (p > 0.05 for all five MR methods). This study demonstrated an association between increased risk of PCa and folic acid supplementation, but not with dietary folate equivalents. These findings have implications for public health interventions and personalized preventive strategies for PCa.

Maternal Folic Acid and Dietary Folate Intake in Relation to Sex Ratio at Birth and Sex-Specific Birth Weight in China.

It is well-established that prenatal folic acid supplements can reduce neural tube defects. However, the associations between folic acid supplementation, dietary folate intake, and overall folate intake with sex-specific birth outcomes are not yet fully understood. This study aims to investigate the association of periconceptional folic acid supplement, dietary folate, and total folate intake with the sex ratio at birth and sex-specific birth weight. Data were sourced from a cross-sectional survey conducted between August and December 2013 in Northwest China, involving 7318 infants and their mothers, recruited using a stratified multistage random sampling method. Folic acid supplements (400 μg/d) were ascertained via a retrospective in-person interview. Dietary folate was evaluated using a validated food frequency questionnaire. Birth outcomes, including sex and weight at birth, were obtained from the Medical Certificate of Birth. Generalized linear models were employed to calculate relative risks (RRs) or differences with 95% confidence intervals (CIs). No association or dose-response relationship was observed between folic acid supplement, dietary folate, and total folate intake during periconception and the likelihood of male births. However, women who took folic acid supplements during pre- and post-conception were associated with an increased male birth weight by 52.8 (8.1 to 97.5) g. Additionally, the total folate intake during periconception was associated with birth weight for males (upper vs. lower tertile: β = 38.8, 95%CI: 5.0 to 72.5 g, p-trend = 0.024) and females (upper vs. lower tertile: β = 42.4, 95%CI: 6.7 to 78.1; p-trend = 0.022). Our findings indicate that periconceptional total folate intake does not correlate with sex ratio at birth but was positively linked to infant birth weights, regardless of gender. These findings offer novel insights into potential benefits of total folate intake, beyond the prevention of neural tube defects, for policymakers and public health.

Maternal Dietary Deficiency in Choline Reduced Levels of MMP-2 Levels in Blood and Brain Tissue of Male Offspring Mice.

Ischemic stroke is one of the leading causes of disability and death globally, with a rising incidence in younger age groups. It is well known that maternal diet during pregnancy and lactation is vital for the early neurodevelopment of offspring. One-carbon (1C) metabolism, including folic acid and choline, plays a vital role in closure of the neural tube in utero. However, the impact of maternal dietary deficiencies in 1C on offspring neurological function following ischemic stroke later in life remains undefined. The aim of this study was to investigate inflammation in the blood and brain tissue of offspring from mothers deficient in dietary folic acid or choline. Female mice were maintained on either a control or deficient diet prior to and during pregnancy and lactation. When offspring were 3 months of age, ischemic stroke was induced. One and a half months later, blood and brain tissue were collected. We measured levels of matrix metalloproteases (MMP)-2 and 9 in both plasma and brain tissue, and reported reduced levels of MMP-2 in ChDD male offspring in both tissue types. No changes were observed in MMP-9. This observation supports our working hypothesis that maternal dietary deficiencies in folic acid or choline during early neurodevelopment impact the levels of inflammation in offspring after ischemic stroke.

Dietary folic acid intake, 13 genetic variants and other factors with red blood cell folate concentration in pregnancy-preparing population

PurposeThis study aims to evaluate a combined effect of dietary folic acid intake, multiple genetic polymorphisms in folate metabolism, and other environmental factors on red blood cell (RBC) folate concentration in pregnancy-preparing population.Methods519 pregnancy-preparing subjects (260 couples) were investigated. Dietary intake was measured by 3-day dietary recalls. 13 Single Nucleotide polymorphisms (SNPs) reported in association with one-carbon metabolism including the methylenetetrahydrofolate reductase (MTHFR) C677T and A1298C were genotyped. RBC folate concentration was measured using chemiluminescence assay. Hierarchical regression was applied for covariate selection. Factors showed significance(p < 0.0125) on RBC folate level was included for prediction model construction and R2 estimation. Validation cohort analysis was performed as post-hoc analysis if applicable.ResultsThe median RBC folate was 212.8 ng/ml. Only 10% took folic acid supplementation within three months. Based on hierarchical selection, folic acid supplementation, genetic polymorphism (especially TT genotype of MTHFR C677T), serum folate level were determinants of the variance of RBC folate concentrations, with adjusted R2 of 0.178–0.242. MTHFR A1298C polymorphism, sex difference with other socio-demographic and lifestyle factors (age, BMI, alcohol drinking, smoking, education, occupation) explained little to change in RBC folate level. Validation in another sub-cohort(n = 8105) had adjusted R2 of 0.273.ConclusionIn pregnancy-preparing subjects, folic acid supplementation, serum folate level and TT allele of MTHFR C677T polymorphism were determinants of the total variance of RBC folate level, which explained 19.8% variance in our subjects and 27.3% in the validation cohort. Food folate intake, sex and other environmental factors explained little to RBC folate level.

Dietary intakes of vitamin B6, folate, vitamin B12 and erectile dysfunction: a national population-based study.

While deficiencies in vitamin B6, folate, and vitamin B12 are linked to various human diseases, including anemia, depression, peripheral neuropathy, and cardiovascular disease (CVD), literature regarding the association between vitamin B6, folate, and vitamin B12 and erectile dysfunction (ED) is scarce. We aimed to determine the dietary intake of vitamin B6, folate, and vitamin B12 and ED in the United States population. We extracted data from the 2001-2004 cycles of the National Health and Nutrition Examination Survey (NHANES). Dietary intakes of B vitamins were collected based on one 24-hour dietary recall. The association between dietary intake of vitamin B6, folate, vitamin B12 and ED was examined using multivariate logistic regression models. A total of 3,875 participants were included for analysis, with 1,201 reporting ED and 2,894 not experiencing ED. The multivariable odds ratios (ORs) for the highest vs. lowest quartiles of vitamin B6 was 0.77 [95% confidence interval (CI): 0.60-0.99; P for trend =0.03] for the prevalence of ED. Subgroup analyses demonstrated a significant inverse association between dietary intake of vitamin B6, folate, vitamin B12 and the prevalence of ED among men aged ≤60 years, individuals of Mexican American and non-Hispanic White ethnicity, and those without a history of CVD, diabetes, hypertension, and high cholesterol. The consumption of dietary vitamin B6, folate, and vitamin B12 was significantly linked to decreased risks of ED among younger healthier men, suggesting a potential protective role of these nutrients against ED in United States adults.

Placental-brain axis in females detected within broadly impacted metabolic gene networks protects against prenatal PCB exposure.

Neurodevelopmental disorders have a strong male bias that is poorly understood. Placenta is a rich source of molecular information about environmental interactions with genetics (including biological sex), that affect the developing brain. We investigated placental-brain transcriptional responses in an established mouse model of prenatal exposure to a human-relevant mixture of polychlorinated biphenyls (PCBs). To understand sex, tissue, and dosage effects in embryonic (E18) brain and placenta by RNAseq, we used weighted gene correlation network analysis (WGCNA) to create correlated gene networks that could be compared across sex or tissue. WGCNA revealed that expression within most correlated gene networks was significantly and strongly associated with PCB exposures, but frequently in opposite directions between male-female and placenta-brain comparisons. In both WGCNA and differentially expressed gene analyses, male brain showed more PCB-induced transcriptional changes than male placenta, but the reverse pattern was seen in females. Furthermore, non-monotonic dose responses to PCBs were observed in most gene networks but were most prominent in male brain. The transcriptomic effects of low dose PCB exposure were significantly reversed by dietary folic acid supplementation across both sexes, but these effects were strongest in female placenta. PCB-dysregulated and folic acid-reversed gene networks were commonly enriched in functions in metabolic pathways involved in energy usage and translation, with female-specific protective effects enriched in PPAR, thermogenesis, glycerolipids, and O-glycan biosynthesis, as opposed to toxicant responses in male brain. The female protective effect in prenatal PCB exposures appears to be mediated by dose-dependent sex differences in transcriptional modulation of metabolism in placenta.

Folate intake and colorectal cancer risk according to genetic subtypes defined by targeted tumor sequencing

BackgroundFolate is involved in multiple genetic, epigenetic, and metabolic processes, and inadequate folate intake has been associated with an increased risk of cancer. ObjectiveWe examined whether folate intake is differentially associated with colorectal cancer (CRC) risk according to somatic mutations in genes linked to CRC using targeted sequencing. DesignParticipants within 2 large CRC consortia with available information on dietary folate, supplemental folic acid, and total folate intake were included. Colorectal tumor samples from cases were sequenced for the presence of nonsilent mutations in 105 genes and 6 signaling pathways (IGF2/PI3K, MMR, RTK/RAS, TGF-β, WNT, and TP53/ATM). Multinomial logistic regression models were analyzed comparing mutated/nonmutated CRC cases to controls to compute multivariable-adjusted odds ratios (ORs) with 95% confidence interval (CI). Heterogeneity of associations of mutated compared with nonmutated CRC cases was tested in case-only analyses using logistic regression. Analyses were performed separately in hypermutated and nonhypermutated tumors, because they exhibit different clinical behaviors. ResultsWe included 4339 CRC cases (702 hypermutated tumors, 16.2%) and 11,767 controls. Total folate intake was inversely associated with CRC risk (OR = 0.93; 95% CI: 0.90, 0.96). Among hypermutated tumors, 12 genes (AXIN2, B2M, BCOR, CHD1, DOCK3, FBLN2, MAP3K21, POLD1, RYR1, TET2, UTP20, and ZNF521) showed nominal statistical significance (P < 0.05) for heterogeneity by mutation status, but none remained significant after multiple testing correction. Among these genetic subtypes, the associations between folate variables and CRC were mostly inverse or toward the null, except for tumors mutated for DOCK3 (supplemental folic acid), CHD1 (total folate), and ZNF521 (dietary folate) that showed positive associations. We did not observe differential associations in analyses among nonhypermutated tumors, or according to the signaling pathways. ConclusionsFolate intake was not differentially associated with CRC risk according to mutations in the genes explored. The nominally significant differential mutation effects observed in a few genes warrants further investigation.

Maternal dietary deficiency in choline reduced levels of MMP-2 levels in blood and brain tissue of male offspring mice.

Ischemic stroke is one of the leading causes of disability and death globally, with a rising incidence in younger age groups. It's well known that maternal diet during pregnancy and lactation is vital for the early neurodevelopment of offspring. One-carbon (1C) metabolism, including folic acid and choline, plays a vital role in closure of the neural tube in utero. However, the impact of maternal dietary deficiencies in 1C on offspring neurological function following ischemic stroke later in life remains undefined. The aim of this study was to investigate inflammation in blood and brain tissue of offspring from mothers deficient in dietary folic acid or choline. Female mice were maintained on either a control or deficient diets prior to and during pregnancy and lactation. When offspring were 3-months of age, ischemic stroke was induced. One and half months later blood and brain tissue were collected. We measured levels of matrix-metalloproteases (MMP)-2 and 9 in both plasma and brain tissue, and report reduced levels of MMP-2 in both, with no changes observed in MMP-9. This observation supports our working hypothesis that maternal dietary deficiencies in folic acid or choline during early neurodevelopment impact the levels of inflammation in offspring after ischemic stroke.

A potential association between recent increased incidence of breast and uterine body cancers in Japanese women and changes in dietary saturated fat and folate intake: A meta-analysis

Recent increases in breast and uterine body cancers among Japanese women suggest the involvement of some modifiable factors in cancer development, including drinking and smoking habits, which are generally associated with Westernized lifestyles. Using national data on annual cancer incidence, this study examines the associations between recent changes in cancer incident rates and dietary habits. Data on age-specific incidence and mortality rates of breast, uterine body, colon, and lung cancers from 2004 to 2019, as well as annual changes in the intake of animal protein, plant protein, saturated fatty acids, and folate from 2001 to 2019 among Japanese women, were obtained from e-Stat, a portal site of Japanese Government Statistics. The analysis indicates that the incidence rates of breast and uterine body cancers among Japanese women increased from 2004 to 2019, displaying distinct distribution patterns with two peaks for breast cancer and one peak for uterine body cancer. The rising incidence rates of both cancers were positively correlated with annual changes in animal protein and saturated fat intake and inversely correlated with changes in plant protein and folate intake. Health-care professionals should be aware of the notable and characteristic increase in breast and uterine body cancer incidence among Japanese women and emphasize the importance of lifestyle modifications to counteract Westernized dietary habits.

Managing Normal Tension Glaucoma with Dietary Folate

Normal-Tension Glaucoma (NTG) is the most prevalent form of glaucoma among individuals in Asian countries. While lowering intraocular pressure (IOP) remains the standard of care, this approach is insufficient for most NTG patients. Recent evidence documents the role of ischemia and oxidative stress as critical factors affecting the optic nerve in NTG. Consequently, addressing these factors has been recommended as a neuroprotective strategy. While conventional treatment strategies primarily target the reduction of IOP, this yields limited efficacy and eventual blindness in many NTG cases. Recent studies document another crucial parameter: Retinal Venous Pressure (RVP). Elevated RVP impedes retinal perfusion, resulting in oxidative stress and localized ischemia, and exacerbating optic nerve damage in NTG. Elevated RVP also appears to be a contributing factor in small vessel ischemia associated with diabetic retinopathy and macular degeneration. The underlying cause of elevated RVP is small vessel endotheliopathy, which may result from alterations in methylation and B-vitamin metabolism, leading to changed microcirculation. This metabolic disruption can arise from dietary inadequacies, malabsorption, or genetic polymorphisms affecting the methylation pathways. Restoring plasma levels of folate and B-12 can be achieved through supplementation with natural forms of these vitamins, specifically L-methylfolate, and methylcobalamin. Unlike oxidized folate (folic acid), which must be enzymatically converted to methylfolate to penetrate the blood-retinal barrier, L-methylfolate can be directly utilized. Excess unmetabolized folic acid can impede methyl folate absorption into the retina, underscoring the necessity of using methyl folate for effective supplementation. We propose integrating RVP screening into NTG risk assessments and consider a targeted vitamin supplement, such as Ocufolin®, as a viable adjunct approach to manage elevated RVP and potentially mitigate NTG progression.

Dietary folate intake and serum klotho levels in adults aged 40-79 years: a cross-sectional study from the national health and nutrition examination survey 2007-2016.

This study aims to explore the relationship between dietary folate intake and serum Klotho levels in adults from aged 40 to 79 years in the United States, seeking to elucidate the intricacies of their interaction. Analyzing data from the National Health and Nutrition Examination Survey (NHANES) spanning 2007 to 2016. The survey research determined folate intake through a 24-h dietary recall and nutrient density modeling, and assessed Klotho levels using enzyme-linked immunosorbent assay (ELISA). The relationship between folate intake and Klotho levels was evaluated using weighted linear regression, and complemented by analysis via smoothed curve models for nuanced understanding. The study encompassed 10,278 participants, with an average age of 57.64 years, revealing a noteworthy positive correlation between dietary folate and serum Klotho levels. The regression coefficient stood at 0.11 (95% confidence interval, 0.05, 0.18) post-adjustment for various covariates. When dietary folate intake was categorized into quartiles, the second, third, and fourth quartiles exhibited statistically significant differences compared to the lowest quartile. This indicates that higher folate intake correlates with increased serum Klotho levels. These findings underscore the potential benefits of elevating folate intake to enhance serum Klotho levels. Stratified analysis indicated that this association was more pronounced among males aged 60 years or older and individuals with hypertension. The findings suggest a significant correlation between increased dietary folate intake and elevated serum Klotho levels in adults aged 40-79 years. Hinting at the potential nutritional influences on the aging process and associated health conditions. This calls for further exploration into the mechanisms and broader implications of this association.