Vitamin B12: one carbon metabolism, fetal growth and programming for chronic disease. Eur J Clin Nutr. 2014;68:2-7. [PMID: 24219896 DOI: 10.1038/ejcn.2013.232]

Untargeted metabolic profiling of high-dose methotrexate toxicity shows alteration in betaine metabolism

Cardiotoxicity is a well-established adverse effect of several drugs across multiple therapeutic indications. It is particularly prevalent following anticancer therapy. In order to evaluate the changes in cellular metabolism associated with methotrexate cardiotoxicity, we treated Wistar rats with a single high dose of methotrexate (HDMTX), and after five days, the animals were sacrificed. We then analyzed the cardiotoxicity parameters in serum like Cardiac enzymes(CK-MB, Troponin T, ALP), Inflammatory markers (TNF-α and IL-6), oxidative stress markers (NO, NOX-2), histopathology and cardiac tissue with the goal of identifying a metabolic signature of cardiotoxicity using discovery-based metabolomics. The biochemical parameters for cardiac enzymes, oxidative stress and inflammatory markers showed a significant increase in all three categories in rats treated with HDMTX. These findings were mirrored in the histopathological analysis confirming cardiotoxicity due to HDMTX. The results showed a total of 95 metabolites that were found to be significantly (p < 0.05) modulated: either up- or downregulated in the HDMTX-treated group when compared with the control group. Using integrated pathway analysis we found these metabolites were associated with many important cardiac tissue metabolic pathways, such as the malate aspartate shuttle, taurine and hypotaurine metabolism, betaine metabolism, spermidine biosynthesis, and homocysteine degradation. Among them, L-arginine, homocysteine, and betaine were significantly upregulated, suggesting their possible association with cardiac tissue injury. Overall, we provided evidence for using untargeted metabolomics to identify novel metabolites associated with HDMTX cardiac toxicity.

Alterations in trace elements and cation profiles in transfusion-dependent thalassemia patients

BACKGROUND

Transfusion-dependent thalassemia (TDT) is a severe form of beta-thalassemia, characterized by defective-globin production, resulting in a buildup of unpaired alpha globin chains. Patients with TDT can only survive if they receive safe blood transfusions regularly, which causes iron overload in their blood, which causes a variety of disorders. Cations and trace elements in TDT patients as a drug target deserve more studies.

OBJECTIVES

In the present study, the cations and some trace elements were studied in TDT patients as a tool to adjust their level in the case of any disturbances.

METHODS

Serum calcium, magnesium, zinc, copper, and iron were measured spectrophotometrically while manganese and cobalt were measured by flameless atomic absorption spectroscopy in 100 TDT patients and compared with 35 healthy control children.

RESULTS

Patients with TDT exhibit a notable elevation in blood levels of iron, copper, copper/zinc ratio, and manganese, with a substantial reduction in serum levels of zinc, magnesium, calcium, and cobalt, as compared to the control group. These minerals have diverse associations with clinical data and transfusion frequencies. The receiver operating characteristic (ROC) analysis revealed that the elevated levels of iron, manganese, and calcium exhibit the greatest diagnostic capability, with a sensitivity and specificity of over 80 %, and a Youdin's J value of more than 0.6.

CONCLUSION

The levels of cations and trace elements are disturbed in TDT patients. Hence, the monitoring and adjustment of the level of these minerals are important to prevent further consequences.

Dietary nutrients during gestation cause obesity and related metabolic changes by altering DNA methylation in the offspring

Growing evidence shows that maternal nutrition from preconception until lactation has an important effect on the development of non-communicable diseases in the offspring. Biological responses to environmental stress during pregnancy, including undernutrition or overnutrition of various nutrients, are transmitted in part by DNA methylation. The aim of the present narrative review is to summarize literature data on altered DNA methylation patterns caused by maternal macronutrient or vitamin intake and its association with offspring's phenotype (obesity and related metabolic changes). With our literature search, we found evidence for the association between alterations in DNA methylation pattern of different genes caused by maternal under- or overnutrition of several nutrients (protein, fructose, fat, vitamin D, methyl-group donor nutrients) during 3 critical periods of programming (preconception, pregnancy, lactation) and the development of obesity or related metabolic changes (glucose, insulin, lipid, leptin, adiponectin levels, blood pressure, non-alcoholic fatty liver disease) in offspring. The review highlights that maternal consumption of several nutrients could individually affect the development of offspring's obesity and related metabolic changes via alterations in DNA methylation.

Vitamin B12 Deficiency and the Nervous System: Beyond Metabolic Decompensation-Comparing Biological Models and Gaining New Insights into Molecular and Cellular Mechanisms

Vitamin B12 (VitB12) is a micronutrient and acts as a cofactor for fundamental biochemical reactions: the synthesis of succinyl-CoA from methylmalonyl-CoA and biotin, and the synthesis of methionine from folic acid and homocysteine. VitB12 deficiency can determine a wide range of diseases, including nervous system impairments. Although clinical evidence shows a direct role of VitB12 in neuronal homeostasis, the molecular mechanisms are yet to be characterized in depth. Earlier investigations focused on exploring the biochemical shifts resulting from a deficiency in the function of VitB12 as a coenzyme, while more recent studies propose a broader mechanism, encompassing changes at the molecular/cellular levels. Here, we explore existing study models employed to investigate the role of VitB12 in the nervous system, including the challenges inherent in replicating deficiency/supplementation in experimental settings. Moreover, we discuss the potential biochemical alterations and ensuing mechanisms that might be modified at the molecular/cellular level (such as epigenetic modifications or changes in lysosomal activity). We also address the role of VitB12 deficiency in initiating processes that contribute to nervous system deterioration, including ROS accumulation, inflammation, and demyelination. Consequently, a complex biological landscape emerges, requiring further investigative efforts to grasp the intricacies involved and identify potential therapeutic targets.

A meta-analysis of epigenome-wide association studies on pregnancy vitamin B12 concentrations and offspring DNA methylation

Circulating vitamin B12 concentrations during pregnancy are associated with offspring health. Foetal DNA methylation changes could underlie these associations. Within the Pregnancy And Childhood Epigenetics Consortium, we meta-analysed epigenome-wide associations of circulating vitamin B12 concentrations in mothers during pregnancy (n = 2,420) or cord blood (n = 1,029), with cord blood DNA methylation. Maternal and newborn vitamin B12 concentrations were associated with DNA methylation at 109 and 7 CpGs, respectively (False Discovery Rate P-value <0.05). Persistent associations with DNA methylation in the peripheral blood of up to 482 children aged 4-10 y were observed for 40.7% of CpGs associated with maternal vitamin B12 and 57.1% of CpGs associated with newborn vitamin B12. Of the CpGs identified in the maternal meta-analyses, 4.6% were associated with either birth weight or gestational age in a previous work. For the newborn meta-analysis, this was the case for 14.3% of the identified CpGs. Also, of the CpGs identified in the newborn meta-analysis, 14.3% and 28.6%, respectively, were associated with childhood cognitive skills and nonverbal IQ. Of the 109 CpGs associated with maternal vitamin B12, 18.3% were associated with nearby gene expression. In this study, we showed that maternal and newborn vitamin B12 concentrations are associated with DNA methylation at multiple CpGs in offspring blood (PFDR<0.05). Whether this differential DNA methylation underlies associations of vitamin B12 concentrations with child health outcomes, such as birth weight, gestational age, and childhood cognition, should be further examined in future studies.

Associations Between Prenatal Blood Metals and Vitamins and Cord Blood Peptide Hormone Concentrations

Background

Nonessential metals have endocrine disrupting properties, interfere with cellular processes, generate reactive oxygen and deplete antioxidants, while essential metals and vitamins act as antioxidants. The extent to which prenatal metals and vitamins are associated with cord blood hormones involved in maternal and fetal metabolic and growth processes is unknown.

Methods

We measured six nonessential (arsenic, barium, cadmium, cesium, lead, mercury) and four essential (magnesium, manganese, selenium, zinc) metals and trace elements, and two vitamins (B12 and folate) in first trimester blood from participants in the longitudinal pre-birth Project Viva cohort, who were recruited between 1999-2002 in eastern Massachusetts. We measured adiponectin, C-peptide, IGF-1, IGF-2, IGFBP-3, insulin, and leptin concentrations in cord blood (~n=695). We used covariate-adjusted quantile g-computation for mixtures and linear regression for individual exposures to estimate associations with cord blood peptide hormones.

Results

The essential metal mixture (magnesium, manganese, selenium, zinc) was associated with higher IGF-1 (β=3.20 ng/ml per quartile, 95% CI: 0.39, 6.01), IGF-2 (β=10.93 ng/ml, 95% CI: 0.08, 21.79), and leptin (β=1.03 ng/ml, 95% CI: 0.25, 1.80). Magnesium was associated with higher leptin (β=2.90 ng/ml, 95% CI: 0.89, 4.91), while B12 was associated with lower adiponectin, IGF-2, and leptin, but higher C-peptide. Other individual nonessential metals were associated with cord blood hormones.

Conclusions

Our findings suggest that some prenatal metals and vitamins are associated with cord blood hormones, which may influence growth and development.

Vitamin B12 and Folate Status in Pregnant Females and Their Infants in Norway: Secondary Analysis from the Mommy's Food Study

BACKGROUND

Vitamin B12 and folate are essential micronutrients important for normal infant growth and development.

OBJECTIVES

The aims were to describe vitamin B12 and folate status in pregnant females and their infants according to commonly used status cutoffs and examine the associations between maternal status, maternal supplement use, and breastfeeding and infant status.

METHODS

Pregnant females were recruited at 18 wk gestation in Bergen, Norway. Maternal vitamin B12 and folate status were measured at gestational weeks 18 (n = 136) and 36 (n = 116), and infant status was measured at ages 3 (n = 73) and 6 (n = 74) mo.

RESULTS

At gestational weeks 18 and 36, respectively, 4.4% and 2.6% of the mothers had plasma cobalamin concentrations <148 pmol/L, 0.7% and 6.9% had methylmalonic acid (MMA) concentrations >0.26 μmol/L, and 3.7% and 30% had folate concentrations <10 nmol/L. None of the females had total homocysteine (t-Hcy) concentrations >13 μmol/L or 3 combined indicator of vitamin B12 (cB12) < -0.5. At 3 and 6 mo, respectively, 4.1% and 5.4% of the infants had cobalamin concentrations <148 pmol/L, 63% and 74% had t-Hcy concentrations >6.5 μmol/L, 59% and 66% had MMA concentrations >0.26 μmol/L, and 47% and 60% had cB12 > -0.5. None of the infants had folate concentrations <10 nmol/L. Several of the vitamin B12 biomarkers in infants were associated with maternal vitamin B12 status during pregnancy. Breastfed infants had lower vitamin B12 status (as indicated by plasma cobalamin, t-Hcy, and cB12) than nonbreastfed infants at both 3 and 6 mo. Use of supplements during pregnancy was associated with better vitamin B12 status among infants at 3 and 6 mo, as indicated by infants' cobalamin and t-Hcy concentrations.

CONCLUSIONS

Subclinical vitamin B12 deficiency among infants was common and associated with maternal vitamin B12 status during pregnancy and breastfeeding. Among the mothers, an increase in biochemical folate deficiency was discovered toward the end of gestation. Further studies are needed to investigate clinical consequences. This trial was registered at clinicaltrials.gov as NCT02610959.

Low Levels of Serum Total Vitamin B12 Are Associated with Worse Metabolic Phenotype in a Large Population of Children, Adolescents and Young Adults, from Underweight to Severe Obesity

Vitamin B12 (or cobalamin) is an essential vitamin for DNA synthesis, fatty acid and protein metabolism as well as other metabolic pathways fundamental to the integrity of cells and tissues in humans. It is derived from the diet and mostly stored in the liver. Its deficiency has been associated with metabolic derangements, i.e., obesity, glucose intolerance, increased lipogenesis and metabolic dysfunction-associated steatotic liver disease (MASLD) and steatohepatitis (MASH). However, data with regard to body weight across the whole spectrum (from underweight to severe obesity) in children and young individuals are scarce. The present study aims to describe the association between serum total vitamin B12 and body mass index (BMI) ranging from underweight to severe obesity in a large population of children, adolescents and young adults. This study also investigates associations with visceral adiposity, glucose and lipid metabolism and liver dysfunction. A cross-sectional, single-centre study was conducted at the Paediatrics and Endocrinology units of the "Bambino Gesù Children Hospital", a tertiary referral institution for eating disorders. Clinical charts were reviewed and 601 patients aged from 5 to 25 years were enrolled in order to analyse anthropometric, auxological, clinical, biochemical and liver ultrasound data using robust statistical approaches. Analyses were adjusted for potential confounders. A reduction in serum total B12 levels was associated with a linear increase in body weight, as expressed by WHO BMI SDS (r = -0.31, p < 0.001, BCa 95% -0.38, -0.24). Lower B12 levels were associated with higher waist circumference but only in pubertal girls (r = -0.33, p = 0.008, BCa 95% -0.53, -0.11). Hepatic insulin resistance was higher in males with lower B12 levels (B = -0.003 (-0.007, -0.0001), p = 0.039), but not in females, whereas whole-body insulin resistance was unaffected. Serum lipid profiles (total, HDL and LDL cholesterol and triglycerides) were not influenced by serum cobalamin levels. However, lower cobalamin levels were associated with higher grading of ultrasound-scored hepatic steatosis (ptrend = 0.035). Lastly, both AST and ALT showed a significant and direct correlation with total B12 levels in underweight (r = 0.22 and 0.24, p = 0.002 and <0.001, respectively) and severely obese subjects (r = 0.24 and 0.32, p = 0.002 and <0.001). In conclusion lower vitamin B12 levels are associated with higher body weight, adiposity and with worse metabolic health in a large population of children, adolescents and young adults.

Genetically proxied vitamin B12 and homocysteine in relation to life course adiposity and body composition

OBJECTIVE

Observational studies explore the association between vitamin B12 and obesity. However, causality is not reflected by such observations. We performed a bi-directional Mendelian randomization (MR) study to elucidate the causal relationship of vitamin B12 and homocysteine (Hcy) with life course adiposity and body composition.

METHODS

Two-sample MR analysis was conducted. Independent genetic variants associated with vitamin B12 and Hcy from large-scale genome-wide association studies (GWASs) were utilized as genetic instruments, and their causal effects on five life course adiposity phenotypes (birth weight, body mass index (BMI), childhood BMI, waist circumference, waist-to-hip ratio) and three body compositions (body fat mass, body fat-free mass, body fat percentage) were estimated from UK Biobank, other consortia, and large-scale GWASs. The inverse variance weighting (IVW, main analysis), bi-directional MR, and other six sensitivity MR analyses were performed.

RESULTS

Genetically proxied higher vitamin B12 concentrations were robustly associated with reduced BMI (Beta = -0.01, 95% confidence interval (CI) -0.016 to -0.004, P = 7.60E-04), body fat mass (Beta = -0.012, 95%CI -0.018 to -0.007, P = 1.69E-05), and body fat percentage (Beta = -0.005, 95%CI -0.009 to -0.002, P = 4.12E-03) per SD unit by IVW and other sensitivity analyses. Stratification analysis showed that these results remained significant in females and at different body sites (all P < 0.05 after Bonferroni correction). Bi-directional analyses showed no reverse causation.

CONCLUSIONS

This study provides strong evidence for the causal effect of vitamin B12 on adiposity. This gives novel clues for intervening obesity in public health and nutrition.

Exploring the Interplay Between Vitamin B12-related Biomarkers, DNA Methylation, and Gene-Nutrition Interaction in Esophageal Precancerous Lesions

BACKGROUND

Vitamin B12 depletion has been suggested to be associated with esophageal precancerous lesions (EPL). However, the potential mechanisms remain unclear.

AIMS

This study aims to evaluate the role of vitamin B12 and its regulated epigenetic modification in EPL and provide preliminary information on the identification of potential molecular biomarkers for the early prediction of EPL.

METHODS

We collected information and samples from the Early Diagnosis and Early Treatment Project of Esophageal Cancer database from 200 EPL cases and 200 matched controls. Vitamin B12, one-carbon metabolism biomarkers, genetic polymorphism of TCN2 C776G, and DNA methylation were compared. Preliminarily identified candidate promoters of differentially methylated CpG positions were further verified by targeted bisulfite sequencing.

RESULTS

EPL cases had significantly lower serum levels of vitamin B12 and transcobalamin II, and higher serum levels of homocysteine and 5-methyltetrahydrofolate than controls. The TCN2 C776G polymorphism was found to be associated with susceptibility to EPL and may interact with vitamin B12 nutritional status to influence the risk of EPL in male subjects. In addition, global hypomethylation related to vitamin B12 depletion was observed in EPL cases, along with region-specific hypermethylation of UGT2B15 and FGFR2 promoters.

CONCLUSIONS

This study suggests that vitamin B12 depletion may be associated with aberrant DNA methylation and increased risk of EPL through the one-carbon metabolism pathway, presents that the TCN2 C776G polymorphism may interact with vitamin B12 nutritional status to affect EPL risk in males, and also identifies specific locations in the UGT2B15 and FGFR2 promoters with potential as promising molecular biomarkers.

Vitamin B12 Status before and after Outpatient Treatment of Severe Acute Malnutrition in Children Aged 6-59 Months: A Sub-Study of a Randomized Controlled Trial in Burkina Faso

Severe acute malnutrition (SAM) is treated with ready-to-use therapeutic foods (RUTF) containing a vitamin-mineral premix. Yet little is known about micronutrient status in children with SAM before and after treatment. We aimed to investigate vitamin B12 status in children with uncomplicated SAM, aged 6-59 months in Burkina Faso, before and after treatment with a standard or a reduced dose of RUTF. Blood samples were collected at admission and discharge. Serum B12 was determined with microbiological assay and serum methylmalonic acid (MMA) and total homocysteine (tHcy) were analyzed with gas chromatography-tandem mass spectrometry. B12 status was classified using the combined indicator (3cB12). Among 374 children, the median [interquartile range] age was 11.0 [7.7-16.9] months, and 85.8% were breastfed. Marked or severe B12 deficiency, as judged by 3cB12, decreased from 32% to 9% between admission and discharge (p < 0.05). No differences in B12 status following treatment with either standard (n = 194) or reduced (n = 180) doses of RUTF were observed. Breastfed children showed a lower B12 status (3cB12) than non-breastfed ones (-1.10 vs -0.18, p < 0.001 at admission; -0.44 vs 0.19; p < 0.001 at discharge). In conclusion, treatment of SAM with RUTF improved children's B12 status but did not fully correct B12 deficiency.

Molecular mechanisms involved in fetal programming and disease origin in adulthood

Fetal programming occurs during the gestational age when exposure to environmental stimuli can cause long-term changes in the fetus, predisposing it to develop chronic non-communicable diseases (CNCD) in adulthood. Herein, we summarized the role of low-calorie or high-fat diets during pregnancy as fetal programming agents that induce intrauterine growth restriction (IUGR), amplified de novo lipogenesis, and increased amino acid transport to the placenta, which favor the CNCD onset in the offspring. We also outlined how maternal obesity and gestational diabetes act as fetal programming stimuli by reducing iron absorption and oxygen transport to the fetus, stimulating inflammatory pathways that boost neurological disorders and CNCD in the progeny. Moreover, we reviewed the mechanisms through which fetal hypoxia elevates the offspring's risk of developing hypertension and chronic kidney disease in adult life by unbalancing the renin-angiotensin system and promoting kidney cell apoptosis. Finally, we examined how inadequate vitamin B12 and folic acid consumption during pregnancy programs the fetus to greater adiposity, insulin resistance, and glucose intolerance in adulthood. A better understanding of the fetal programming mechanisms may help us reduce the onset of insulin resistance, glucose intolerance, dyslipidemia, obesity, hypertension, diabetes mellitus, and other CNCD in the offspring during adulthood.

Maternal Vitamin B12 Status during Pregnancy and Early Infant Neurodevelopment: The ECLIPSES Study

In this prospective cohort study of 434 mother-infant pairs from the ECLIPSES study, we examine the association between maternal vitamin B12 status at the beginning and end of pregnancy and the neurodevelopmental outcomes of infants 40 days after birth in a pregnant population from a Mediterranean region of northern Spain. Maternal vitamin B12 concentrations were determined in the first and third trimesters, and sociodemographic, nutritional, and psychological data were collected. At 40 days postpartum, the Bayley Scales of Infant Development-III (BSID-III, cognitive, language, and motor skills) were administered to the infants and several obstetrical data were recorded. In the multivariable models, medium maternal first-trimester vitamin B12 levels (312 to 408 pg/mL, tertile 2) were associated with better neonatal performance in the motor, gross motor, language, and cognitive skills with respect to tertile 1 (<312 pg/mL). The probability of obtaining a neonatal motor, gross motor, and receptive language score >75th percentile was significantly higher also in the tertile 2 group. In summary, good maternal vitamin B12 status in the early stage of pregnancy appears to be associated with better infant motor, language, and cognitive performance at 40 days postpartum.

Bi-directional causal effect between vitamin B12 and non-alcoholic fatty liver disease: Inferring from large population data

Objectives

Many observational studies evaluate the association between vitamin B12 and non-alcoholic fatty liver disease (NAFLD). However, the causality of this association remains uncertain, especially in European populations. We conducted a bidirectional Mendelian randomization study to explore the association between vitamin B12 and NAFLD.

Methods

Two-sample Mendelian randomization study was conducted. Summary statistics for vitamin B12 were acquired from a genome-wide association studies (GWAS) meta-analysis including 45,576 subjects. Summary-level data for NAFLD was obtained from a GWAS meta-analysis of 8,434 cases and 770,180 non-cases and another GWAS meta-analysis of 1,483 cases and 17,781 non-cases. Summary-level data for 4 enzymes including alkaline phosphatase (ALP), alanine aminotransferase (ALT), aspartate aminotransferase (AST), and gamma glutamyltransferase (GGT), was available from the UK Biobank. Inverse variance weighting (as main analysis), weighted median estimate, robust adjusted profile score, MR-Egger, and MR-PRESSO (sensitivity analyses) were performed to calculate causal estimates.

Results

Genetically predicted higher vitamin B12 concentrations were consistently associated with an increased NAFLD in two sources. The combined odds ratio (OR) of NAFLD was 1.30 (95% confidence interval (CI), 1.13 to 1.48; p < 0.001) per SD-increase in vitamin B12 concentrations. Genetic liability to NAFLD was also positively associated with vitamin B12 concentrations (Beta 0.08, 95%CI, 0.01 to 0.16; p = 0.034). Sensitivity analyses also revealed consistent results. Genetically predicted vitamin B12 concentrations showed no significant association with liver enzymes.

Conclusion

The present study indicates that increased serum vitamin B12 concentrations may play a role in NAFLD risk. NAFLD also has a causal impact on elevated vitamin B12 concentrations in the circulation. Notably, vitamin B12 concentrations imply the levels of vitamin B12 in the circulation, and higher intake of vitamin B12 may not directly lead to higher levels of serum vitamin B12, instead the higher levels of vitamin B12 in the circulation may be caused by the dysregulation of the metabolism of this vitamin in this study. There exist bidirectional causal effects between serum vitamin B12 concentrations and risk of NAFLD in European individuals.

Role of Prenatal Nutrition in the Development of Insulin Resistance in Children

Nutrition during the prenatal period is crucial for the development of insulin resistance (IR) and its consequences in children. The relationship between intrauterine environment, fetal nutrition and the onset of IR, type 2 diabetes (T2D), obesity and metabolic syndrome later in life has been confirmed in many studies. The intake of carbohydrates, protein, fat and micronutrients during pregnancy seems to damage fetal metabolism programming; indeed, epigenetic mechanisms change glucose-insulin metabolism. Intrauterine growth restriction (IUGR) induced by unbalanced nutrient intake during prenatal life cause fetal adipose tissue and pancreatic beta-cell dysfunction. In this review we have summarized and discussed the role of maternal nutrition in preventing insulin resistance in youth.

Correlations between serum vitamin B12 and folate levels among mother-infant dyads in Punjab state, North-West India

AIM

Adequate vitamin B12 levels in infancy are crucial for normal psychomotor and cognitive development of infants. Our aim was to examine serum vitamin B12, folate and ferritin levels in exclusively breastfed healthy full-term infants (age group: 1-6 months), and also investigate their correlation with maternal markers.

METHODS

A cross-sectional study was conducted on 100 exclusively breastfed healthy full-term infants (age group: 1-6 months) along with their lactating mothers. Serum vitamin B12, folate and ferritin levels were determined for each mother-infant dyad using enzyme-linked immunosorbent assay.

RESULTS

The mean serum vitamin B12, folate and ferritin levels were 512 vs. 535 pg/mL, 15 vs. 12 ng/mL and 313 vs. 114 ng/mL in infants and mothers, respectively. Among 100 infants, 26 (26%) had lower vitamin B12 levels and 5 (5%) had inadequate folate levels. In addition, 22 (22%) of 100 lactating mothers were deficient in vitamin B12 levels and 14 (14%) had inadequate folate levels. We found a statistically significant positive correlation between infant and maternal vitamin B12 (r = 0.659, P < 0.001) and folate levels (r = 0.51, P < 0.001).

CONCLUSION

Vitamin B12 deficiency was observed in 26% of infants and 22% of lactating mothers. Vitamin B12 and folate levels of infants were positively correlated with maternal levels in the state of Punjab, North-West India. Our findings support that maternal vitamin B12 status can be used as a valuable predictor of infant vitamin B12 status.

Exploring Gut Microbiome in Predicting the Efficacy of Immunotherapy in Non-Small Cell Lung Cancer

We performed various analyses on the taxonomic and functional features of the gut microbiome from NSCLC patients treated with immunotherapy to establish a model that may predict whether a patient will benefit from immunotherapy. We collected 65 published whole metagenome shotgun sequencing samples along with 14 samples from our previous study. We systematically studied the taxonomical characteristics of the dataset and used both the random forest (RF) and the multilayer perceptron (MLP) neural network models to predict patients with progression-free survival (PFS) above 6 months versus those below 3 months. Our results showed that the RF classifier achieved the highest F-score (85.2%) and the area under the receiver operating characteristic curve (AUC) (95%) using the protein families (Pfam) profile, and the MLP neural network classifier achieved a 99.9% F-score and 100% AUC using the same Pfam profile. When applying the model trained in the Pfam profile directly to predict the treatment response, we found that both trained RF and MLP classifiers significantly outperformed the stochastic predictor in F-score. Our results suggested that such a predictive model based on functional (e.g., Pfam) rather than taxonomic profile might be clinically useful to predict whether an NSCLC patient will benefit from immunotherapy, as both the F-score and AUC of functional profile outperform that of taxonomic profile. In addition, our model suggested that interactive biological processes such as methanogenesis, one-carbon, and amino acid metabolism might be important in regulating the immunotherapy response that warrants further investigation.

Effects of dietary supplementation of different levels of vitamin B12 on the liver metabolism of laying hens

BACKGROUND

Vitamin B₁₂ plays an important role in lipid, protein, carbohydrate and nucleic acid metabolism. We investigated the effect of supplementing layers' diets with different vitamin B₁₂ levels on liver metabolism using a liquid chromatography-mass spectrometry-based metabolomic approach to observe and analyse wide-target metabolomics in the liver.

RESULTS

We assigned hens to three groups, namely blank control group without vitamin B₁₂ diet (BCG), normal control group with 25 μg kg^-1 vitamin B₁₂ (NCG) and vitamin B₁₂ supplement group I with 100 μg kg^-1 vitamin (VBSG I). The VBSG I group layers had higher (P < 0.05) vitamin B₁₂ concentration than those from other groups. The egg yolk vitamin B₁₂ concentration increased (P < 0.01) with the increasing vitamin B₁₂ dietary supplemental level. Between the NCG versus BCG, VBSG I versus BCG, and VBSG I versus NCG groups, 11, 20 and 11 metabolites were significantly changed, respectively. The KEGG pathway of vitamin B₆ metabolism was significantly impacted in the NCG layers than those from BCG; seven and five pathways were significantly impacted in the VBSG I layers compared with those from BCG and NCG, including pyrimidine metabolism, vitamin B₆ metabolism, glycerophospholipid metabolism, etc. CONCLUSION: We concluded that 25 μg kg^-1 vitamin B₁₂ supplementation in corn-soybean meal-based layer diet increased the egg yolk vitamin B₁₂ concentration and impacted the vitamin B₆ metabolic pathway, and 100 μg kg^-1 of it increased the egg yolk and liver vitamin B₁₂ concentrations and impacted vitamin B₆ , lipid, nucleic acid and amino acid metabolic pathways. © 2022 Society of Chemical Industry.

High Folate, Perturbed One-Carbon Metabolism and Gestational Diabetes Mellitus

Folate is a dietary micronutrient essential to one-carbon metabolism. The World Health Organisation recommends folic acid (FA) supplementation pre-conception and in early pregnancy to reduce the risk of fetal neural tube defects (NTDs). Subsequently, many countries (~92) have mandatory FA fortification policies, as well as recommendations for periconceptional FA supplementation. Mandatory fortification initiatives have been largely successful in reducing the incidence of NTDs. However, humans have limited capacity to incorporate FA into the one-carbon metabolic pathway, resulting in the increasingly ubiquitous presence of circulating unmetabolised folic acid (uFA). Excess FA intake has emerged as a risk factor in gestational diabetes mellitus (GDM). Several other one-carbon metabolism components (vitamin B12, homocysteine and choline-derived betaine) are also closely entwined with GDM risk, suggesting a role for one-carbon metabolism in GDM pathogenesis. There is growing evidence from in vitro and animal studies suggesting a role for excess FA in dysregulation of one-carbon metabolism. Specifically, high levels of FA reduce methylenetetrahydrofolate reductase (MTHFR) activity, dysregulate the balance of thymidylate synthase (TS) and methionine synthase (MTR) activity, and elevate homocysteine. High homocysteine is associated with increased oxidative stress and trophoblast apoptosis and reduced human chorionic gonadotrophin (hCG) secretion and pancreatic β-cell function. While the relationship between high FA, perturbed one-carbon metabolism and GDM pathogenesis is not yet fully understood, here we summarise the current state of knowledge. Given rising rates of GDM, now estimated to be 14% globally, and widespread FA food fortification, further research is urgently needed to elucidate the mechanisms which underpin GDM pathogenesis.

Association of vitamin B12/ferritin deficiency in cancer patients with methylomic changes at promotors of TET methylcytosine dioxygenases

Aim: To investigate potential DNA methylation in methylcytosine dioxygenases and correlation of TET genes with vitamin B12/ferritin levels in cancer patients. Materials & methods: 200 blood samples were obtained from both cancer patients and healthy individuals. Results: The expression of DNMT1, DNMT3a and DNMT3b was increased in patients with low vitamin B12 and ferritin levels, while the expression of MTR, TET1 and TET3 significantly decreased. DNA methylation analysis in patients with deficient vitamin B12/ferritin levels showed methylomic changes within the location 318/CG and 385/CG in the promoter region of TET1 and TET3, respectively. Conclusion: Vitamin B12/ferritin deficiency contributes to DNA methylation progress in cancer patients.

Maternal Mental Health in Late Pregnancy and Longitudinal Changes in Postpartum Serum Vitamin B-12, Homocysteine, and Milk B-12 Concentration Among Brazilian Women

Background

Little is known regarding the association between mental health distress during pregnancy and postpartum maternal serum biomarkers of vitamin B-12 status and milk B-12 concentration.

Objective

To evaluate the association between depressive and anxiety symptoms in the third trimester of pregnancy and changes in postpartum serum B-12, homocysteine, and B-12 milk concentration.

Methods

A total of 101 women (18–40 years) were studied in a prospective cohort with data at the third trimester of pregnancy (baseline) and three postpartum time-points (TPs): 2–8 days (TP1), 28–50 days (TP2), and 88-119 days (TP3) postpartum. B-12 concentrations in milk were measured by competitive chemiluminescent enzyme immunoassay at TP1, TP2, and TP3. Serum B-12 and homocysteine concentrations were evaluated at baseline, TP1, TP2, and TP3 by chemiluminescent immunoassays. Depressive and anxiety symptoms were measured with the Edinburgh Postnatal Depression Scale and the State-Trait Anxiety Inventory at baseline. Spearman's correlation test and multiple linear mixed-effect models were performed.

Results

The prevalence of depressive and anxiety state symptoms was 35.6 and 39.6% at baseline. High prevalence of low milk B-12 concentration (<310 pmol/L) were observed at TP1 (53.2%), TP2 (71.4%), and TP3 (71.1%). Women with anxiety symptoms at baseline presented higher median concentrations of serum homocysteine at TP1 and lower concentrations of serum and milk B-12 at TP2 compared with women without anxiety symptoms [8 (7; 9) vs. 6 (5; 8) and 266 (188; 369) vs. 332 (272; 413)]. Milk B-12 concentrations were positively and significantly correlated with maternal serum B-12 concentrations at different TP. Women with anxiety symptoms at baseline exhibited a decrease in daily postpartum homocysteine concentrations compared to women without anxiety symptoms (β = −0.002, SE = 0.001, p = 0.024).

Conclusion

Anxiety symptoms at the end of pregnancy were associated with longitudinal changes in maternal serum homocysteine concentrations during the first 3 months postpartum.

SMAD4 Controls Cancer Cell Metabolism by Regulating Methylmalonic Aciduria Cobalamin Deficiency (cbl) B Type

Suppressor of mothers against decapentaplegic homolog (SMAD) 4 is a pluripotent signaling mediator that regulates myriad cellular functions, including cell growth, cell division, angiogenesis, apoptosis, cell invasion, and metastasis, through transforming growth factor β (TGF-β)-dependent and -independent pathways. SMAD4 is a critical modulator in signal transduction and functions primarily as a transcription factor or cofactor. Apart from being a DNA-binding factor, the additional SMAD4 mechanisms in tumor suppression remain elusive. We previously identified methyl malonyl aciduria cobalamin deficiency B type (MMAB) as a critical SMAD4 binding protein using a proto array analysis. This study confirmed the interaction between SMAD4 and MMAB using bimolecular fluorescence complementation (BiFC) assay, proximity ligation assay (PLA), and conventional immunoprecipitation. We found that transient SMAD4 overexpression down-regulates MMAB expression via a proteasome-dependent pathway. SMAD4-MMAB interaction was independent of TGF-β signaling. Finally, we determined the effect of MMAB downregulation on cancer cells. siRNA-mediated knockdown of MMAB affected cancer cell metabolism in HeLa cells by decreasing ATP production and glucose consumption as well as inducing apoptosis. These findings suggest that SMAD4 controls cancer cell metabolism by regulating MMAB.

Prevalence and Risk Factors of Vitamin B12 Deficiency among Pregnant Women in Rural Bangladesh

Vitamin B12 deficiency is associated with an increased risk of pregnancy complications and adverse birth outcomes. However, data on vitamin B12 deficiency in pregnant Bangladeshi women are limited. This study examines vitamin B12 deficiency and marginal deficiency in rural Bangladeshi women during early and late pregnancies. Some 522 women whose gestational age was <20 weeks were recruited. Serum vitamin B12 concentrations were measured at baseline and after 14 weeks of iron-folate supplementation. Logistic regression analysis examined the association of various socio-demographic, dietary, and pregnancy-related factors with vitamin B12 deficiency and marginal deficiency. Overall, 19% of the women during early pregnancy had vitamin B12 deficiency (serum vitamin B12 concentration < 203 pg/mL) and nearly 40% had marginal deficiency (serum vitamin B12 concentration 203 to <300 pg/mL). Vitamin B12 deficiency doubled to 38% during late pregnancy, while marginal deficiency slightly increased to 41.7%. The pregnant women with a gestational age of ≥27 weeks had a higher risk of developing vitamin B12 deficiency (OR = 2.61; 95% CI = 1.096−6.214) than those of a gestational age of <27 weeks. Vitamin B12 deficiency was significantly higher in pregnant women in rented accommodation (OR = 13.32; 95% CI = 1.55−114.25) than in those living in their own house. Vitamin B12 deficiency was significantly higher among women who consumed red or organ meat <3 times a week than in those who consumed it more often (OR = 2.327, 95% CI = 1.194−4.536). None of these factors were significantly associated with marginal vitamin B12 deficiency. In conclusion, vitamin B12 deficiency and marginal deficiency among pregnant rural Bangladeshi women increased as their pregnancies progressed. Increasing gestational age, living in a rented house, and the consumption of red or organ meat <3 times a week were identified as the independent risk factors of vitamin B12 deficiency in this population. Further research with more in-depth assessments of dietary vitamin B12 intakes is needed to develop an intervention program preventing vitamin B12 deficiency in this population.

Association between Vitamin B12 and Risk of Gastric Cancer: A Systematic Review and Meta-Analysis of Epidemiological Studies

Epidemiological studies focusing on the association between vitamin B₁₂ and gastric cancer risk reported inconsistent findings. We conducted a systematic review and meta-analysis to assess the relationship. PubMed (Medline), Web of science and EMBASE databases were systematically searched. A total of nine studies involving 3,494 cases of with gastric cancer and 611,638 participants were included. The result showed that there is no significant association between vitamin B₁₂ intake and the risk of gastric cancer (OR = 0.88, 95% CI: 0.69-1.12, P = 0.303). Nevertheless, high intake of vitamin B₁₂ might decrease the risk of gastric cancer in Helicobacter pylori (Hp)-negative people (OR = 0.83, 95% CI: 0.62-0.99, P = 0.044), but increase the cancer risk in Hp-positive populations (OR = 1.66, 95% CI: 1.27-2.16, P = 10^-4). Additionally, further analysis indicated that excessive vitamin B₁₂ might increase the risk of non-cardia gastric cancer (OR = 1.15, 95% CI: 1.01-1.33, P = 0.006). A negative association between vitamin B₁₂ intake and gastric cancer risk was found in nonsmokers (OR = 0.83, 95% CI: 0.71-0.96, P = 0.012) but not in smokers (OR = 1.08, 95% CI: 0.71-1.47, P = 0.619). In conclusion, although we found no convincing evidence that vitamin B₁₂ intake is associated with the risk of gastric cancer, it is important to maintain the relative stability of vitamin B₁₂ for people with Hp infection.

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.

Epigenetics of pregnancy: looking beyond the DNA code

Epigenetics is the branch of genetics that studies the different mechanisms that influence gene expression without direct modification of the DNA sequence. An ever-increasing amount of evidence suggests that such regulatory processes may play a pivotal role both in the initiation of pregnancy and in the later processes of embryonic and fetal development, thus determining long-term effects even in adult life. In this narrative review, we summarize the current knowledge on the role of epigenetics in pregnancy, from its most studied and well-known mechanisms to the new frontiers of epigenetic regulation, such as the role of ncRNAs and the effects of the gestational environment on fetal brain development. Epigenetic mechanisms in pregnancy are a dynamic phenomenon that responds both to maternal-fetal and environmental factors, which can influence and modify the embryo-fetal development during the various gestational phases. Therefore, we also recapitulate the effects of the most notable environmental factors that can affect pregnancy and prenatal development, such as maternal nutrition, stress hormones, microbiome, and teratogens, focusing on their ability to cause epigenetic modifications in the gestational environment and ultimately in the fetus. Despite the promising advancements in the knowledge of epigenetics in pregnancy, more experience and data on this topic are still needed. A better understanding of epigenetic regulation in pregnancy could in fact prove valuable towards a better management of both physiological pregnancies and assisted reproduction treatments, other than allowing to better comprehend the origin of multifactorial pathological conditions such as neurodevelopmental disorders.

Interactions between Radiation and One-Carbon Metabolism

Metabolic reprogramming is a hallmark of cancer. Cancer cells rewire one-carbon metabolism, a central metabolic pathway, to turn nutritional inputs into essential biomolecules required for cancer cell growth and maintenance. Radiation therapy, a common cancer therapy, also interacts and alters one-carbon metabolism. This review discusses the interactions between radiation therapy, one-carbon metabolism and its component metabolic pathways.

Aquatic Animal Foods for Nutrition Security and Child Health

BACKGROUND

Aquatic animal source foods (AASF) can provide vital nutrients and bioactive factors essential for human health, yet disparities in consumption patterns prevail globally. Limited evidence exists for the implications of AASF access on child health outcomes.

OBJECTIVE

This study aimed to examine global AASF intakes longitudinally in association with critical nutrient intakes and childhood stunting and anemia.

METHODS

The analysis draws from compiled longitudinal country data (1993-2013) based on a constructed conceptual framework encompassing social and ecological factors that influence fish consumption and human health. Longitudinal generalized linear models were used to estimate the association of apparent AASF intake on country-level nutrient availability (docosahexaenoic acid [DHA], choline, vitamin B₁₂, iron, and zinc) and prevalence of undernourishment, child stunting, and child anemia.

RESULTS

Across 175 countries, the median per capita daily apparent intake of all AASF was 37.87 g, with marginally significant differences observed between countries with low (46.65 g) versus high child mortality (23.50 g). The combined category of all AASF was significantly associated with increased total apparent intakes of DHA, choline, and vitamin B₁₂ and reduced child stunting. Finfish (pelagic and demersal) and crustaceans inversely correlated with child stunting, while apparent intakes of mollusks and crustaceans were associated with reduced child anemia.

CONCLUSIONS

This study uniquely showed that AASF were associated with improved child health outcomes and the critical nutrients necessary for growth, development, and maintaining health throughout the life course. Policies should ensure increased access to AASF across food systems and within sustainable healthy diets globally.

Diets, nutrients, genes and the microbiome: recent advances in personalised nutrition

As individuals seek increasingly individualised nutrition and lifestyle guidance, numerous apps and nutrition programmes have emerged. However, complex individual variations in dietary behaviours, genotypes, gene expression and composition of the microbiome are increasingly recognised. Advances in digital tools and artificial intelligence can help individuals more easily track nutrient intakes and identify nutritional gaps. However, the influence of these nutrients on health outcomes can vary widely among individuals depending upon life stage, genetics and microbial composition. For example, folate may elicit favourable epigenetic effects on brain development during a critical developmental time window of pregnancy. Genes affecting vitamin B12 metabolism may lead to cardiometabolic traits that play an essential role in the context of obesity. Finally, an individual's gut microbial composition can determine their response to dietary fibre interventions during weight loss. These recent advances in understanding can lead to a more complete and integrated approach to promoting optimal health through personalised nutrition, in clinical practice settings and for individuals in their daily lives. The purpose of this review is to summarise presentations made during the DSM Science and Technology Award Symposium at the 13th European Nutrition Conference, which focused on personalised nutrition and novel technologies for health in the modern world.

Spectroscopic and computational insight into the conformational dynamics of hemoglobin in the presence of vitamin B12

Protein-ligand interactions play a significant role in all living organisms, thereby affecting the design and application of drugs and other biomaterials. The current study reports the binding of vitamin B12 to hemoglobin, employing optical spectroscopy and computational methods. It is observed that vitamin B12 quenched the intrinsic fluorescence of hemoglobin. The nature of quenching appears to be static according to the steady-state and time-resolved fluorescence measurements. The conformational changes of hemoglobin caused by vitamin B12 interactions were studied by synchronous fluorescence spectroscopy and protein secondary structure analyses. The synchronous fluorescence spectra indicate the tryptophan residue microenvironment change while no secondary structural change is observed from circular dichroism spectra and molecular dynamics (MD) simulation study. The computational molecular docking elucidated the probable binding of vitamin B12 at the active site of hemoglobin, whereas the stability of the hemoglobin-vitamin B12 complex was studied by MD simulation. The study might be helpful for the treatment of pernicious anemia, hereditary transcobalamin deficiency, and performance enhancement of elite athletes.

Enhancing in vitro oocyte maturation competence and embryo development in farm animals: roles of vitamin-based antioxidants – a review

Oocyte/embryo in vitro culture is one of the most important assisted reproductive technologies used as a tool for maintaining genetic resources biodiversity and the inheritance of valuable genetic resources through generations. The success of such processes affects the final goal of the in vitro culture, getting viable and healthy offspring. In common in vitro oocyte maturation and/or embryo development techniques, the development of oocytes/embryos is carried out at 5% carbon dioxide and roughly 20% atmosphere-borne oxygen ratios in cell culture incubators due to their reduced cost in comparison with low atmospheric oxygen-tension incubators. These conditions are usually accompanying by the emergence of reactive oxygen species (ROS), which can extremely damage cell membrane integrity and other vital cellular organelles, as well as genetic material. The present review mainly focuses on the antioxidant roles of different vitamins on in vitro oocyte maturation competence and embryo development in farm animals. Because, the conditions of in vitro embryo production (IVEP) are usually accompanying by the emergence of reactive oxygen species (ROS), which can extremely damage cell membrane integrity and other vital cellular organelles as well as genetic material. The use of antioxidant agents may prevent the extreme augmentation of ROS generation and enhance in vitro matured oocyte competence and embryo development. Therefore, this review aimed to provide an updated outline of the impact of antioxidant vitamin (Vit) supplementations during in vitro maturation (IVM) and in vitro fertilization (IVF) on oocyte maturation and consequent embryo development, in various domestic animal species. Thus, the enrichment of the culture media with antioxidant agents may prevent and neutralize the extreme augmentation of ROS generation and enhance the in vitro embryo production (IVEP) outcomes.

Association of dietary intakes of vitamin B12, vitamin B6, folate, and methionine with the risk of esophageal cancer: the Japan Public Health Center-based (JPHC) prospective study

Background

B vitamins and methionine are essential substrates in the one-carbon metabolism pathway involved in DNA synthesis and methylation. They may have essential roles in cancer development. We aimed to evaluate the associations of dietary intakes of vitamin B12, vitamin B6, folate, and methionine with the risk of esophageal cancer (EC) using data from the Japan Public Health Center-based Prospective Study.

Methods

We included 87,053 Japanese individuals who completed a food frequency questionnaire and were followed up from 1995–1998 to 2013 and 2015. Hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated by Cox proportional-hazard regression across quintiles of dietary intakes of B vitamins and methionine.

Results

After 1,456,678 person-years of follow-up, 427 EC cases were documented. The multivariable HR (95% CI) of incident EC in the highest versus lowest quintile of dietary intake of vitamin B12 was 1.75 (1.13–2.71; p-trend=0.01). Stratification analysis based on alcohol consumption showed that higher dietary intakes of vitamin B12 and methionine were associated with an increased risk of EC among never-drinkers; HRs (95% CIs) were 2.82 (1.18–6.74; p-trend=0.009; p-interaction=0.18) and 3.45 (1.32–9.06; p-trend=0.003; p-interaction 0.02) for vitamin B12 and methionine, respectively. Meanwhile, there was no association between vitamin B12 and methionine intake with the risk of EC among drinkers. There were no associations between dietary intake of folate or vitamin B6 and the risk of EC.

Conclusion

Dietary intake of vitamin B12 was positively associated with the risk of EC in the Japanese population.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08721-8.

Contribution of genetic ancestry and polygenic risk score in meeting vitamin B12 needs in healthy Brazilian children and adolescents

Polymorphisms in genes related to the metabolism of vitamin B12 haven’t been examined in a Brazilian population. To (a) determine the correlation between the local genetic ancestry components and vitamin B12 levels using ninety B12-related genes; (b) determine associations between these genes and their SNPs with vitamin B12 levels; (c) determine a polygenic risk score (PRS) using significant variants. This cross-sectional study included 168 children and adolescents, aged 9–13 years old. Total cobalamin was measured in plasma. Genotyping arrays and whole exome data were combined to yield ~ 7000 SNPs in 90 genes related to vitamin B12. The Efficient Local Ancestry Inference was used to estimate local ancestry for African (AFR), Native American, and European (EUR). The association between the genotypes and vitamin B12 levels were determined with generalized estimating equation. Vitamin B12 levels were driven by positive (EUR) and negative (AFR, AMR) correlations with genetic ancestry. A set of 36 variants were used to create a PRS that explained 42% of vitamin level variation. Vitamin B12 levels are influenced by genetic ancestry and a PRS explained almost 50% of the variation in plasma cobalamin in Brazilian children and adolescents.

Interaction between Metformin, Folate and Vitamin B12 and the Potential Impact on Fetal Growth and Long-Term Metabolic Health in Diabetic Pregnancies

Metformin is the first-line treatment for many people with type 2 diabetes mellitus (T2DM) and gestational diabetes mellitus (GDM) to maintain glycaemic control. Recent evidence suggests metformin can cross the placenta during pregnancy, thereby exposing the fetus to high concentrations of metformin and potentially restricting placental and fetal growth. Offspring exposed to metformin during gestation are at increased risk of being born small for gestational age (SGA) and show signs of ‘catch up’ growth and obesity during childhood which increases their risk of future cardiometabolic diseases. The mechanisms by which metformin impacts on the fetal growth and long-term health of the offspring remain to be established. Metformin is associated with maternal vitamin B₁₂ deficiency and antifolate like activity. Vitamin B₁₂ and folate balance is vital for one carbon metabolism, which is essential for DNA methylation and purine/pyrimidine synthesis of nucleic acids. Folate:vitamin B₁₂ imbalance induced by metformin may lead to genomic instability and aberrant gene expression, thus promoting fetal programming. Mitochondrial aerobic respiration may also be affected, thereby inhibiting placental and fetal growth, and suppressing mammalian target of rapamycin (mTOR) activity for cellular nutrient transport. Vitamin supplementation, before or during metformin treatment in pregnancy, could be a promising strategy to improve maternal vitamin B₁₂ and folate levels and reduce the incidence of SGA births and childhood obesity. Heterogeneous diagnostic and screening criteria for GDM and the transient nature of nutrient biomarkers have led to inconsistencies in clinical study designs to investigate the effects of metformin on folate:vitamin B₁₂ balance and child development. As rates of diabetes in pregnancy continue to escalate, more women are likely to be prescribed metformin; thus, it is of paramount importance to improve our understanding of metformin’s transgenerational effects to develop prophylactic strategies for the prevention of adverse fetal outcomes.

Correlation of vitamin B12 level with insulin resistance in infant and placenta outcomes

OBJECTIVE

This study aims to assess the correlation of vitamin B12 level with insulin resistance toward the outcome of the baby and the placenta.

METHOD

This study used a prospective cohort study design. The total sampling was 87 people. The samples were pregnant women the second trimester and the third trimester. Data were analyzed using the Chi-Square test and the Spearman test. Pregnant women who were respondents were monitored until birth; then, the examination of the baby's weight and placental weight after the baby was born using a scale was carried out.

RESULTS

The result of this study shows that there is no significant correlation between levels of vitamin B12 and insulin resistance (ρ=0.864, p>0.05), there is no significant correlation between vitamin B12 and infant weight (p=0.107, p>0.05), there is no significant correlation between vitamin B12 and placental weight (ρ=0.107, p>0.05). There is no significant correlation between insulin resistance and infant weight (ρ=0.845, p>0.05), and there is no significant correlation between insulin resistance and placental weight (ρ=0.845, p>0.05).

CONCLUSION

There is no correlation of vitamin B12 with insulin resistance toward the outcome of the baby and the placenta.

The Molecular Basis of Alcohol Use Disorder (AUD). Genetics, Epigenetics, and Nutrition in AUD: An Amazing Triangle

Alcohol use disorder (AUD) is a very common and complex disease, as alcohol is the most widely used addictive drug in the world. This disorder has an enormous impact on public health and social and private life, and it generates a huge number of social costs. Alcohol use stimulates hypothalamic-pituitary-adrenal (HPA) axis responses and is the cause of many physical and social problems (especially liver disease and cancer), accidental injury, and risky sexual behavior. For years, researchers have been trying to identify the genetic basis of alcohol use disorder, the molecular mechanisms responsible for its development, and an effective form of therapy. Genetic and environmental factors are known to contribute to the development of AUD, and the expression of genes is a complicated process that depends on epigenetic modulations. Dietary nutrients, such as vitamins, may serve as one these modulators, as they have a direct impact on epigenomes. In this review, we connect gathered knowledge from three emerging fields-genetics, epigenetics, and nutrition-to form an amazing triangle relating to alcohol use disorder.

Maternal Vitamin B12 Status During Pregnancy and Its Association With Outcomes of Pregnancy and Health of the Offspring: A Systematic Review and Implications for Policy in India

Background

Vitamins B12 and folate participate in the one-carbon metabolism cycle and hence regulate fetal growth. Though vitamin B12 deficiency is widely prevalent, the current public health policy in India is to supplement only iron and folic acid for the prevention of anaemia. Prompted by our research findings of the importance of maternal vitamin B12 status for a healthy pregnancy, birth and offspring health outcomes, we evaluated available literature evidence using a systematic review approach, to inform policy.

Methods

A systematic search was performed for relevant Indian studies in the MEDLINE/PubMed and IndMed databases. We selected studies reporting maternal vitamin B12 status (dietary intake or blood concentrations), and/or metabolic markers of vitamin B12 deficiency (homocysteine, methylmalonic acid) or haematological indices during pregnancy and their associations with outcomes of pregnancy, infancy or in later life. Intervention trials of vitamin B12 during pregnancy were also included. Quality of evidence was assessed on the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system. We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement.

Results

Of the 635 articles identified, 46 studies met the inclusion criteria (cohort studies-26, case-control studies-13, RCT's -7). There is a high prevalence of vitamin B12 deficiency in Indian women during pregnancy (40-70%) (3 studies). Observational studies support associations (adjusted for potential sociodemographic confounders, maternal body size, postnatal factors) of lower maternal B12, higher homocysteine or an imbalance between vitamin B12-folate status with a higher risk of NTDs (6 studies), pregnancy complications (recurrent pregnancy losses, gestational diabetes, pre-eclampsia) (9 studies), lower birth weight (10 studies) and adverse longer-term health outcomes in the offspring (cognitive functions, adiposity, insulin resistance) (11 studies). Vitamin B12 supplementation (7 RCT's) in pregnancy showed a beneficial effect on offspring neurocognitive development and an effect on birth weight was inconclusive. There is a high quality evidence to support the role of low maternal vitamin B12 in higher risk for NTD and low birth weight and moderate-quality evidence for higher risk of gestational diabetes and later life adverse health outcomes (cognitive functions, risk for diabetes) in offspring.

Conclusion

In the Indian population low maternal vitaminB12 status, is associated with adverse maternal and child health outcomes. The level of evidence supports adding vitamin B12 to existing nutritional programs in India for extended benefits on outcomes in pregnancy and offspring health besides control of anaemia.

Systematic Review Registration

[website], identifier [registration number].

B12 Deficiency and Clinical Presentation in the Setting of Nitric Oxide Use

B12 deficiency can arise symptomatically from an array of varying pathologies including frank deficiency from strict vegan diets. Other high-risk contributing pathological conditions include chronic alcoholism, autoimmune disease, and chronic gastrointestinal inflammatory disorders, and it is also seen in those with a history of gastric surgery. Additionally, the elderly are at an increased risk as are patients prescribed certain medications. Uncommonly suspected causes of B12 deficiency include the abuse of recreational nitrous oxide (NO) given its interference with cobalt oxidation. Here, we report two cases of hypovitaminosis B12 in association with NO abuse in an effort to highlight an increasingly dangerous trend with recreational use. Importantly, we aim to increase visibility of this malady given that improperly diagnosed neurologic deterioration following NO anesthesia has been shown to become irreversible and may even result in death.

The Role of the Transsulfuration Pathway in Non-Alcoholic Fatty Liver Disease

The prevalence of non-alcoholic fatty liver disease (NAFLD) is increasing and approximately 25% of the global population may have NAFLD. NAFLD is associated with obesity and metabolic syndrome, but its pathophysiology is complex and only partly understood. The transsulfuration pathway (TSP) is a metabolic pathway regulating homocysteine and cysteine metabolism and is vital in controlling sulfur balance in the organism. Precise control of this pathway is critical for maintenance of optimal cellular function. The TSP is closely linked to other pathways such as the folate and methionine cycles, hydrogen sulfide (H₂S) and glutathione (GSH) production. Impaired activity of the TSP will cause an increase in homocysteine and a decrease in cysteine levels. Homocysteine will also be increased due to impairment of the folate and methionine cycles. The key enzymes of the TSP, cystathionine β-synthase (CBS) and cystathionine γ-lyase (CSE), are highly expressed in the liver and deficient CBS and CSE expression causes hepatic steatosis, inflammation, and fibrosis in animal models. A causative link between the TSP and NAFLD has not been established. However, dysfunctions in the TSP and related pathways, in terms of enzyme expression and the plasma levels of the metabolites (e.g., homocysteine, cystathionine, and cysteine), have been reported in NAFLD and liver cirrhosis in both animal models and humans. Further investigation of the TSP in relation to NAFLD may reveal mechanisms involved in the development and progression of NAFLD.

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.

Review of Vitamin B12 deficiency in pregnancy: a diagnosis not to miss as veganism and vegetarianism become more prevalent

Vegetarianism and veganism are increasingly popular. The Food Standards Agency, biennial Food and You Survey of adults aged 16 years and over living in the UK, found that between 2012 and 2018 the proportion of people who reported never consuming dairy products had increased from 2% to 5%. However, veganism risks development of vitamin B12 deficiency as it is not available from plant sources. Moreover, its impact may be slow to be detected because body stores of vitamin B12 can last years. There is currently no published guidance on antenatal diagnosis and management of vitamin B12 deficiency. This paper reviews the metabolism, diagnosis and treatment of vitamin B12 in pregnancy. It concludes that national screening policymakers should consider introducing screening for B12 deficiency into the Antenatal and Newborn Screening Programmes for mothers and their infants if at risk of vitamin B12 deficiency. In the interim, national policy should be developed for prophylactic vitamin B12 supplementation in high-risk groups around the time of pregnancy.

Assessment of Serum Vitamin B12 and Folate Levels and Macrocytosis in Patients with Type 2 Diabetes Mellitus on Metformin Attending Tikur Anbessa Specialized Hospital, Addis Ababa, Ethiopia: A Cross-Sectional Study

BACKGROUND

Metformin is the first-line drug in the treatment of type 2 diabetes mellitus. Monitoring vitamin B₁₂ deficiency associated with long-term and high-dose therapy is not a common practice in many clinical settings in Ethiopia.

OBJECTIVE

The study aimed to measure levels of serum vitamin B₁₂ and folate and to assess the macrocytic status of type 2 diabetes mellitus patients on metformin.

METHODS

A cross-sectional study was conducted on 80 type 2 diabetes mellitus patients who had been on metformin for 5 months or more at the diabetic clinic of Tikur Anbessa Specialized Teaching Hospital. Serum vitamin B₁₂ and folate levels were quantified by chemiluminescent immunoassays. Mean corpuscular volume was determined by complete blood count. Differences in vitamin B₁₂ and folate levels and mean corpuscular volume between different groups were assessed using Kruskal-Wallis H and Mann-Whitney U tests.

RESULTS

Vitamin B₁₂ and folate deficiency were documented in 5% and 23.8% of participants, respectively, and 6.2% of patients were macrocytic. Levels of vitamin B₁₂ and folate in patients who had been on metformin >1,500 mg/day ≥4 years were significantly lower those who had been on metformin 1,000-1,500 mg/day and <1,000 mg/day <4 years, respectively.

CONCLUSION

Low serum vitamin B₁₂ and folate levels and macrocytosis were found to be associated with prolonged metformin treatment.

Porphyrin metalation catalyzed by DNAzymes and nanozymes

In this review, DNA and nanomaterial based catalysts for porphyrin metalation reactions are summarized, including the selection of DNAzymes, choice of nanomaterials, their catalytic mechanisms, and applications of the reactions.

Maternal Glucose and LDL-Cholesterol Levels Are Related to Placental Leptin Gene Methylation, and, Together With Nutritional Factors, Largely Explain a Higher Methylation Level Among Ethnic South Asians

BACKGROUND

Leptin, mainly secreted by fat cells, plays a core role in the regulation of appetite and body weight, and has been proposed as a mediator of metabolic programming. During pregnancy leptin is also secreted by the placenta, as well as being a key regulatory cytokine for the development, homeostatic regulation and nutrient transport within the placenta. South Asians have a high burden of type 2 diabetes, partly attributed to a "thin-fat-phenotype".

OBJECTIVE

Our aim was to investigate how maternal ethnicity, adiposity and glucose- and lipid/cholesterol levels in pregnancy are related to placental leptin gene (LEP) DNA methylation.

METHODS

We performed DNA methylation analyses of 13 placental LEP CpG sites in 40 ethnic Europeans and 40 ethnic South Asians participating in the STORK-Groruddalen cohort.

RESULTS

South Asian ethnicity and gestational diabetes (GDM) were associated with higher placental LEP methylation. The largest ethnic difference was found for CpG11 [5.8% (95% CI: 2.4, 9.2), p<0.001], and the strongest associations with GDM was seen for CpG5 [5.2% (1.4, 9.0), p=0.008]. Higher maternal LDL-cholesterol was associated with lower placental LEP methylation, in particular for CpG11 [-3.6% (-5.5, -1.4) per one mmol/L increase in LDL, p<0.001]. After adjustments, including for nutritional factors involved in the one-carbon-metabolism cycle (vitamin D, B12 and folate levels), ethnic differences in placental LEP methylation were strongly attenuated, while associations with glucose and LDL-cholesterol persisted.

CONCLUSIONS

Maternal glucose and lipid metabolism is related to placental LEP methylation, whilst metabolic and nutritional factors largely explain a higher methylation level among ethnic South Asians.

Moderately high folate level may offset the effects of aberrant DNA methylation of P16 and P53 genes in esophageal squamous cell carcinoma and precancerous lesions

BACKGROUND

This study evaluated gene-nutrition interactions between folate and the aberrant DNA methylation of tumor suppressor genes in different stages of carcinogenesis of esophageal squamous cell carcinoma (ESCC).

METHODS

Two hundred ESCC cases, 200 esophageal precancerous lesion (EPL) cases, and 200 controls matched by age (± 2 years) and gender were used for this study. Baseline data and dietary intake information was collected via questionnaire. The serum folate levels and methylation status of promoter regions of p16 and p53 were detected.

RESULTS

The interactions of increased serum folate level with unmethylated p16 and p53 promoter regions were significantly associated with a reduced risk of both EPL and ESCC (p for interaction < 0.05). The interactions of the lowest quartile of serum folate level with p16 or p53 methylation was significantly associated with an increased risk of ESCC (OR = 2.96, 95% CI, 1.45-6.05; OR = 2.34, 95% CI, 1.15-4.75). An increased serum folate level was also related to a decreasing trend of EPL and ESCC risks when p16 or p53 methylation occurred. The interaction of spinach, Chinese cabbage, liver and bean intake with unmethylated p16 and p53 was significantly associated with a reduced risk of EPL or ESCC (p for interaction < 0.05).

CONCLUSIONS

The interactions between a high folate level and unmethylated p16 and p53 promoter regions may have a strong preventive effect on esophageal carcinogenesis. Additionally, a high folate level may offset the tumor-promoting effects of aberrant DNA methylation of the genes, but it is also noteworthy that a very high level of folate may not have a protective effect on EPL in some cases.