Alterations in one­carbon metabolism and protein synthesis signals due to methionine supplementation and lipopolysaccharide challenge in Holstein fetal liver explants.

One­carbon metabolism (OCM) fueled by methionine (Met), choline, and folic acid is key for embryo development and fetal growth. We investigated effects of lipopolysaccharide (LPS) to induce inflammation in fetal liver tissue with or without Met on components of OCM and protein synthesis activity. Fetal liver harvested at slaughter from six multiparous pregnant Holstein dairy cows (37 ± 6 kg milk/d, 100 ± 3 d gestation) were incubated (0.2 ± 0.02 g) for 4 h at 37 °C with each of the following: ideal profile of amino acids (control; Lysine:Met 2.9:1), control plus LPS (1 µg/mL), increased Met supply (Met, Lys:Met 2.5:1), and Met+LPS. Data were analyzed as a 2 × 2 factorial (PROC MIXED, SAS 9.4). Ratios of mechanistic target of rapamycin (p-mTOR:mTOR) and eukaryotic elongation factor 2 (p-eEF2:eEF2) protein were lowest (P < 0.0 5) with LPS and highest with Met. Tissue amino acid concentrations were lowest (P < 0.0 5) with Met regardless of LPS suggesting enhanced use via mTOR. The marked increase (P = 0.02) in phosphorylation of S6 ribosomal protein (p-RPS6) with LPS suggested a pro-inflammatory response that was partly alleviated with Met+LPS. No effect (P = 0.4 5) on methionine adenosyl transferase 1 A (MAT1A) protein abundance was detected. Activity of betaine-homocysteine S-methyltransferase (BHMT) was greatest with Met, but Met+LPS dampened this effect (P = 0.0 5). Overall, fetal liver responds to inflammatory challenges and Met supply. The latter can stimulate protein synthesis via mTOR and alter some OCM reactions while having a modest anti-inflammatory effect.

Dietary choline intake and its association with asthma: A study based on the National Health and Nutrition Examination Survey database.

OBJECTIVE: This work endeavored to examine the correlation between dietary choline intake and the odds of asthma, utilizing data from the National Health and Nutrition Examination Survey (NHANES). METHODS: Aggregated data from seven cycles (2005-2018) in the NHANES database were utilized. The independent variable was dietary choline intake, and the dependent variable was asthma. The weighted logistic regression method was used to construct a model reflecting the relationship between these two factors. This work employed stratified analysis without adjusting for confounding factors and subgroup analysis with adjusted confounding factors to mine the association between dietary choline intake and asthma. Additionally, restricted cubic spline analysis examined nonlinear associations of the two in age subgroups. RESULTS: Forty five thousand and seven hundreds ninety seven samples were included here. The model indicating the relationship between dietary choline intake and asthma was constructed (OR: 0.86, 95% CI: 0.79-0.93, p < 0.001). Stratified analysis indicated that the interaction terms of age (p < 0.001) and body mass index (BMI) (p = 0.002) with dietary choline intake significantly influenced the relationship model. In the adjusted models, accounting for demographic characteristics, poverty impact ratio, BMI, exposure to environmental tobacco smoke, and total energy intake, an increase in dietary choline intake significantly reduced the odds of asthma (OR: 0.79, 95% CI: 0.72-0.88, p < 0.001). Subgroup analyses based on age and BMI revealed a significant negative correlation between dietary choline intake and the odds of asthma in the adult population (OR: 0.76, 95% CI: 0.67-0.86, p < 0.001), as well as in individuals with a BMI between 25 and 30 kg/m2 (OR: 0.79, 95% CI: 0.63-0.99, p = 0.042), and those with a BMI >30 kg/m2 (OR: 0.73, 95% CI: 0.60-0.89, p = 0.002). CONCLUSION: Dietary choline intake was significantly inversely correlated with asthma prevalence, especially in adults and overweight/obese individuals, suggesting that increasing choline intake may reduce asthma risk. Further research is needed to explore this relationship and provide tailored dietary recommendations for different age and BMI groups to enhance asthma prevention and management.

The Role of One-Carbon Metabolism and Methyl Donors in Medically Assisted Reproduction: A Narrative Review of the Literature.

One-carbon (1-C) metabolic deficiency impairs homeostasis, driving disease development, including infertility. It is of importance to summarize the current evidence regarding the clinical utility of 1-C metabolism-related biomolecules and methyl donors, namely, folate, betaine, choline, vitamin B12, homocysteine (Hcy), and zinc, as potential biomarkers, dietary supplements, and culture media supplements in the context of medically assisted reproduction (MAR). A narrative review of the literature was conducted in the PubMed/Medline database. Diet, ageing, and the endocrine milieu of individuals affect both 1-C metabolism and fertility status. In vitro fertilization (IVF) techniques, and culture conditions in particular, have a direct impact on 1-C metabolic activity in gametes and embryos. Critical analysis indicated that zinc supplementation in cryopreservation media may be a promising approach to reducing oxidative damage, while female serum homocysteine levels may be employed as a possible biomarker for predicting IVF outcomes. Nonetheless, the level of evidence is low, and future studies are needed to verify these data. One-carbon metabolism-related processes, including redox defense and epigenetic regulation, may be compromised in IVF-derived embryos. The study of 1-C metabolism may lead the way towards improving MAR efficiency and safety and ensuring the lifelong health of MAR infants.

Higher dietary methyl donor micronutrient consumption is associated with higher muscle strength in adults: a cross-sectional study.

Methyl donor micronutrients might affect muscle strength via DNA methylation. We aimed to evaluate the combined relationship of dietary methyl donor micronutrients containing betaine, choline, methionine, vitamin B12, vitamin B6 and folate on muscle strength. This cross-sectional study was conducted on 267 subjects including 113 men and 154 women. Dietary intake of micronutrients was assessed utilising a validated 168-item semi-quantitative FFQ, and methyl donor micronutrient score (MDMS) was calculated. The muscle strength of the participants was measured using a digital handgrip dynamometer. The association was determined using linear regression analysis. The mean age of participants was 36·8 ± 13·2 years. After taking into account potential confounding variables, there was no significant association between dietary methyl donor micronutrient score (MDMS) and the mean left-hand muscle strength (ß: 0·07, se: 0·05, P = 0·07); however, the changes were significant in the mean right-hand muscle strength (ß: 0·09, se: 0·04, P = 0·03). There was also a significant positive relationship between mean muscle strength and methyl donors' intake after fully adjusting for potential confounders (ß: 0·08, se: 0·04, P = 0·04). In conclusion, our findings revealed that higher dietary methyl donor micronutrient consumption is associated with enhanced muscle strength. As a result, advice on a higher intake of methyl donor-rich foods including grains, nuts, dairy products and seafood might be recommended by dietitians as a general guideline to adhere to. Additional prospective studies are needed to confirm the findings.

Maternal methyl donor supplementation: A potential therapy for metabolic disorder in offspring.

The prevalences of diabetes mellitus and obesity are increasing yearly and has become a serious social burden. In addition to genetic factors, environmental factors in early life development are critical in influencing the prevalence of metabolic disorders in offspring. A growing body of evidence suggests the critical role of early methyl donor intervention in offspring health. Emerging studies have shown that methyl donors can influence offspring metabolism through epigenetic modifications and changing metabolism-related genes. In this review, we focus on the role of folic acid, betaine, vitamin B12, methionine, and choline in protecting against metabolic disorders in offspring. To address the current evidence on the potential role of maternal methyl donors, we summarize clinical studies as well as experimental animal models that support the impact of maternal methyl donors on offspring metabolism and discuss the mechanisms of action that may bring about these positive effects. Given the worldwide prevalence of metabolic disorders, these findings could be utilized in clinical practice, in which methyl donor supplementation in the early life years may reverse metabolic disorders in offspring and block the harmful intergenerational effect.

Influence of Cobalt Source, Folic Acid, and Rumen-Protected Methionine on Performance, Metabolism, and Liver Tissue One-Carbon Metabolism Biomarkers in Peripartal Holstein Cows.

Vitamin B12 plays a role in the remethylation of homocysteine to Met, which then serves as a substrate for Met adenosyltransferase (MAT) to synthesize S-adenosylmethionine (SAM). We investigated effects of feeding two cobalt sources [Co-glucoheptonate (CoPro) or CoPectin, Zinpro Corp.], an experimental ruminally-available source of folic acid (FOA), and rumen-protected Met (RPM) on performance and hepatic one-carbon metabolism in peripartal Holstein cows. From -30 to 30 d around calving, 72 multiparous cows were randomly allocated to: CoPro, CoPro + FOA, CoPectin + FOA, or CoPectin + FOA + RPM. The Co treatments delivered 1 mg Co/kg of DM (CoPro or CoPectin), each FOA group received 50 mg/d FOA, and RPM was fed at 0.09% of DM intake (DMI). Milk yield and DMI were not affected. Compared with other groups, the percentage of milk protein was greater after the second week of lactation in CoPectin + FOA + RPM. Compared with CoPro or CoPro + FOA, feeding CoPectin + FOA or CoPectin + FOA + RPM led to a greater activity of MAT at 7 to 15 d postcalving. For betaine-homocysteine S-methyltransferase, CoPro together with CoPectin + FOA + RPM cows had greater activity at 7 and 15 d than CoPro + FOA. Overall, supplying FOA with CoPectin or CoPectin plus RPM may enhance S-adenosylmethionine synthesis via MAT in the liver after parturition. As such, these nutrients may impact methylation reactions and liver function.

Influence of methyl donor nutrients as epigenetic regulators in colorectal cancer: A systematic review of observational studies.

BACKGROUND: Dietary methyl donors might influence DNA methylation during carcinogenesis of colorectal cancer (CRC). However, whether the influence of methyl donor intake is modified by polymorphisms in such epigenetic regulators is still unclear. AIM: To improve the current understanding of the molecular basis of CRC. METHODS: A literature search in the Medline database, Reference Citation Analysis (https:// www.referencecitationanalysis.com/), and manual reference screening were performed to identify observational studies published from inception to May 2022. RESULTS: A total of fourteen case-control studies and five cohort studies were identified. These studies included information on dietary methyl donors, dietary components that potentially modulate the bioavailability of methyl groups, genetic variants of methyl metabolizing enzymes, and/or markers of CpG island methylator phenotype and/or microsatellite instability, and their possible interactions on CRC risk. CONCLUSION: Several studies have suggested interactions between methylenetetrahydrofolate reductase polymorphisms, methyl donor nutrients (such as folate) and alcohol on CRC risk. Moreover, vitamin B6, niacin, and alcohol may affect CRC risk through not only genetic but also epigenetic regulation. Identification of specific mechanisms in these interactions associated with CRC may assist in developing targeted prevention strategies for individuals at the highest risk of developing CRC.

Mitigating the detrimental developmental impact of early fetal alcohol exposure using a maternal methyl donor-enriched diet.

Fetal alcohol exposure at any stage of pregnancy can lead to fetal alcohol spectrum disorder (FASD), a group of life-long conditions characterized by congenital malformations, as well as cognitive, behavioral, and emotional impairments. The teratogenic effects of alcohol have long been publicized; yet fetal alcohol exposure is one of the most common preventable causes of birth defects. Currently, alcohol abstinence during pregnancy is the best and only way to prevent FASD. However, alcohol consumption remains astoundingly prevalent among pregnant women; therefore, additional measures need to be made available to help protect the developing embryo before irreparable damage is done. Maternal nutritional interventions using methyl donors have been investigated as potential preventative measures to mitigate the adverse effects of fetal alcohol exposure. Here, we show that a single acute preimplantation (E2.5; 8-cell stage) fetal alcohol exposure (2 × 2.5 g/kg ethanol with a 2h interval) in mice leads to long-term FASD-like morphological phenotypes (e.g. growth restriction, brain malformations, skeletal delays) in late-gestation embryos (E18.5) and demonstrate that supplementing the maternal diet with a combination of four methyl donor nutrients, folic acid, choline, betaine, and vitamin B12, prior to conception and throughout gestation effectively reduces the incidence and severity of alcohol-induced morphological defects without altering DNA methylation status of imprinting control regions and regulation of associated imprinted genes. This study clearly supports that preimplantation embryos are vulnerable to the teratogenic effects of alcohol, emphasizes the dangers of maternal alcohol consumption during early gestation, and provides a potential proactive maternal nutritional intervention to minimize FASD progression, reinforcing the importance of adequate preconception and prenatal nutrition.

Methyl Donors, Epigenetic Alterations, and Brain Health: Understanding the Connection.

Methyl donors such as choline, betaine, folic acid, methionine, and vitamins B6 and B12 are critical players in the one-carbon metabolism and have neuroprotective functions. The one-carbon metabolism comprises a series of interconnected chemical pathways that are important for normal cellular functions. Among these pathways are those of the methionine and folate cycles, which contribute to the formation of S-adenosylmethionine (SAM). SAM is the universal methyl donor of methylation reactions such as histone and DNA methylation, two epigenetic mechanisms that regulate gene expression and play roles in human health and disease. Epigenetic mechanisms have been considered a bridge between the effects of environmental factors, such as nutrition, and phenotype. Studies in human and animal models have indicated the importance of the optimal levels of methyl donors on brain health and behavior across the lifespan. Imbalances in the levels of these micronutrients during critical periods of brain development have been linked to epigenetic alterations in the expression of genes that regulate normal brain function. We present studies that support the link between imbalances in the levels of methyl donors, epigenetic alterations, and stress-related disorders. Appropriate levels of these micronutrients should then be monitored at all stages of development for a healthier brain.

The Effect of Dietary Methyl-Donor Intake and Other Lifestyle Factors on Cancer Patients in Hungary.

BACKGROUND: Nutrition is essential to life and can have an indisputable influence on health and prevention of disease development including cancer. Methyl-donors are macronutrients that are important in achieving a healthy balance of metabolic processes. Their deficiency can lead to several symptoms and diseases-even to severe SARS-CoV-2 infection. We aimed to explore the potential protective effect of methyl-donor intake in breast, colorectal and pancreatic cancer by patient follow up. METHODS: A food frequency questionnaire and a diet diary were used to evaluate methyl-donor intake and blood samples were taken to evaluate Il-6 and IL-8 cytokine levels as well as MTHFR (C677T) polymorphism in breast, colorectal and pancreatic cancer patients. RESULTS: We found that levels around the recommended daily intake of B6 and B9 were effective in supporting the overall survival of breast and colorectal, and a relatively higher level of pancreatic adenocarcinoma, patients. The total intake of methyl-donors significantly and negatively correlated with smoking in pancreatic cancer, while folate as well as betaine intake significantly and positively correlated with IL-8 in colorectal cancer patients. CONCLUSIONS: Our results suggest that the appropriate intake of methyl-donor can be an adjunct of conventional oncotherapy to improve quality of life. Whether methyl-donor intake supports cancer prevention and patient survival needs further confirmation in large patient cohorts.

Methyl Donors Reduce Cell Proliferation by Diminishing Erk-Signaling and NFkB Levels, While Increasing E-Cadherin Expression in Panc-1 Cell Line.

Pancreatic cancer is an aggressive malignancy with high metastatic potential. There are several lifestyle-related determinants in its etiology, including diet. Methyl donors are dietary micronutrients which play an important role in fueling vital metabolic pathways, and as bioactive food components provide methyl groups as substrates and cofactors. The imbalanced nutritional status of methyl donors has recently been linked to pathological conditions. Therefore, we hypothesized that dietary methyl donors may improve the physiology of cancer patients, including those with pancreatic cancer, and could be used for intervention therapy. In this study, methyl-donor treatment (L-methionine, choline chloride, folic acid and vitamin B12) of an aggressive pancreatic adenocarcinoma cell line (Panc-1) resulted in significantly increased p21WAF1/Cip1 cyclin-dependent kinase inhibitor levels, along with apoptotic SubG1 fractions. At the same time, phospho-Erk1/2 levels and proliferation rate were significantly reduced. Though methyl-donor treatments also increased the pro-apoptotic protein Bak, Puma and Caspase-9, it failed to elevate cleaved Caspase-3 levels. In addition, the treatment significantly reduced the production of the pro-inflammatory cytokine IL-17a and the transcription factor NFkB. Similarly, a significant decrease in VEGF and SDF-1a levels were detected, which may indicate reduced metastatic potential. As expected, E-cadherin expression was inversely associated with these changes, showing elevated expression after methyl-donor treatment. In summary, we found that methyl donors may have the potential to reduce aggressive and proliferative phenotype of Panc-1 cells. This suggests a promising role of dietary methyl donors for complementing relevant cancer therapies, even in treatment-resistant pancreatic adenocarcinomas.

One-carbon metabolism in children with marasmus and kwashiorkor.

BACKGROUND: Kwashiorkor is a childhood syndrome of edematous malnutrition. Its precise nutritional precipitants remain uncertain despite nine decades of study. Remarkably, kwashiorkor's disturbances resemble the effects of experimental diets that are deficient in one-carbon nutrients. This similarity suggests that kwashiorkor may represent a nutritionally mediated syndrome of acute one-carbon metabolism dysfunction. Here we report findings from a cross-sectional exploration of serum one-carbon metabolites in Malawian children. METHODS: Blood was collected from children aged 12-60 months before nutritional rehabilitation: kwashiorkor (N = 94), marasmic-kwashiorkor (N = 43) marasmus (N = 118), moderate acute malnutrition (N = 56) and controls (N = 46). Serum concentrations of 16 one-carbon metabolites were quantified using LC/MS techniques, and then compared across participant groups. FINDINGS: Twelve of 16 measured one-carbon metabolites differed significantly between participant groups. Measured outputs of one-carbon metabolism, asymmetric dimethylarginine (ADMA) and cysteine, were lower in marasmic-kwashiorkor (median µmol/L (± SD): 0·549 (± 0·217) P = 0·00045 & 90 (± 40) P < 0·0001, respectively) and kwashiorkor (0·557 (± 0·195) P < 0·0001 & 115 (± 50) P < 0·0001), relative to marasmus (0·698 (± 0·212) & 153 (± 42)). ADMA and cysteine were well correlated with methionine in both kwashiorkor and marasmic-kwashiorkor. INTERPRETATION: Kwashiorkor and marasmic-kwashiorkor were distinguished by evidence of one-carbon metabolism dysfunction. Correlative observations suggest that methionine deficiency drives this dysfunction, which is implicated in the syndrome's pathogenesis. The hypothesis that kwashiorkor can be prevented by fortifying low quality diets with methionine, along with nutrients that support efficient methionine use, such as choline, requires further investigation. FUNDING: The Hickey Family Foundation, the American College of Gastroenterology, the NICHD, and the USDA/ARS.

Fatty acid metabolism and colon cancer protection by dietary methyl donor restriction.

INTRODUCTION: A methyl donor depleted (MDD) diet dramatically suppresses intestinal tumor development in Apc-mutant mice, but the mechanism of this prevention is not entirely clear. OBJECTIVES: We sought to gain insight into the mechanisms of cancer suppression by the MDD diet and to identify biomarkers of cancer risk reduction. METHODS: A plasma metabolomic analysis was performed on ApcΔ14/+ mice maintained on either a methyl donor sufficient (MDS) diet or the protective MDD diet. A group of MDS animals was also pair-fed with the MDD mice to normalize caloric intake, and another group was shifted from an MDD to MDS diet to determine the durability of the metabolic changes. RESULTS: In addition to the anticipated changes in folate one-carbon metabolites, plasma metabolites related to fatty acid metabolism were generally decreased by the MDD diet, including carnitine, acylcarnitines, and fatty acids. Some fatty acid selectivity was observed; the levels of cancer-promoting arachidonic acid and 2-hydroxyglutarate were decreased by the MDD diet, whereas eicosapentaenoic acid (EPA) levels were increased. Machine-learning elastic net analysis revealed a positive association between the fatty acid-related compounds azelate and 7-hydroxycholesterol and tumor development, and a negative correlation with succinate and ß-sitosterol. CONCLUSION: Methyl donor restriction causes dramatic changes in systemic fatty acid metabolism. Regulating fatty acid metabolism through methyl donor restriction favorably effects fatty acid profiles to achieve cancer protection.

Early Life Nutrition and Mental Health: The Role of DNA Methylation.

Does the quality of our diet during early life impact our long-term mental health? Accumulating evidence suggests that nutrition interacts with our genes and that there is a strong association between the quality of diet and mental health throughout life. Environmental influences such as maternal diet during pregnancy or offspring diet have been shown to cause epigenetic changes during critical periods of development, such as chemical modifications of DNA or histones by methylation for the regulation of gene expression. One-carbon metabolism, which consists of the folate and methionine cycles, is influenced by the diet and generates S-Adenosylmethinoine (SAM), the main methyl donor for methylation reactions such as DNA and histone methylation. This review provides current knowledge on how the levels of one-carbon metabolism associated micronutrients such as choline, betaine, folate, methionine and B vitamins that play a role in brain function can impact our well-being and mental health across the lifespan. Micronutrients that act as methyl donors for SAM formation could affect global or gene methylation, altering gene expression and phenotype. Strategies should then be adopted to better understand how these nutrients work and their impact at different stages of development to provide individualized dietary recommendations for better mental health outcomes.

Methyl-Donors Can Induce Apoptosis and Attenuate Both the Akt and the Erk1/2 Mediated Proliferation Pathways in Breast and Lung Cancer Cell Lines.

Dietary methyl-donors play important roles in physiological processes catalyzed by B vitamins as coenzymes, and are used for complementary support in oncotherapy. Our hypothesis was that methyl-donors can not only assist in tolerating cancer treatment but may also directly interfere with tumor growth and proliferation. Therefore, we investigated the proposed cancer inhibitory effects of methyl-donors (in a mixture of L-methionine, choline chloride, folic acid, and vitamin B12) on MCF7 and T47D breast cancer as well as A549 and H1650 lung cancer cell lines. Indeed, methyl-donor treatment significantly reduced the proliferation in all cell lines, possibly through the downregulation of MAPK/ERK and AKT signaling. These were accompanied by the upregulation of the pro-apoptotic Bak and Bax, both in MCF7 and H1650 cells, at reduced anti-apoptotic Mcl-1 and Bcl-2 levels in MCF7 and H1650 cells, respectively. The treatment-induced downregulation of p-p53(Thr55) was likely to contribute to protecting the nuclear localization and apoptosis inducing functions of p53. The presented features are known to improve the sensitivity of cancer therapy. Therefore, these data support the hypothesis, i.e., that methyl-donors may promote apoptotic signaling by protecting p53 functions through downregulating both the MAPK/ERK and the AKT pathways both in breast and lung adenocarcinoma cell lines. Our results can emphasize the importance and benefits of the appropriate dietary supports in cancer treatments. However, further studies are required to confirm these effects without any adverse outcome in clinical settings.

Beneficial and deleterious effects of sitagliptin on a methionine/choline-deficient diet-induced steatohepatitis in rats.

Non-alcoholic fat liver disease (NAFLD) is the most common chronic liver disease in the world. NAFLD is a spectrum of diseases ranging from simple steatosis to hepatic carcinoma. The complexity of pathomechanisms makes treatment difficult. The oral antidiabetic agents, dipeptidyl peptidase four inhibitors (DPP-4i) have been proposed as possible therapeutic agents. This study was performed using a well-established NAFLD model in rats to elucidate whether sitagliptin could prevent steatohepatitis. Rats were fed a methionine/choline-deficient (MCD) diet with or without sitagliptin treatment for six weeks. Liver tissue was examined to estimate sitagliptin's effect on the development of NASH. The MCD diet decreased the SAM/SAH ratio, and increased plasma levels of homocysteine, free fatty acids, and long-chain acylcarnitines in the MCD rats. MMP2 and Col1A2 expression also increased under the MCD diet. Sitagliptin treatment did not reverse these effects and increased steatosis and long-chain acylcarnitines. In conclusion, sitagliptin was ineffective to prevent from NAFLD in the MCD rat model. This result challenges previous data reporting beneficial effects and is consistent with the clinical trials' negative results.

Vitamin E deficiency dysregulates thiols, amino acids and related molecules during zebrafish embryogenesis.

Vitamin E (α-tocopherol, VitE) was discovered as a nutrient essential to protect fetuses, but its molecular role in embryogenesis remains undefined. We hypothesize that the increased lipid peroxidation due to VitE deficiency drives a complex mechanism of overlapping biochemical pathways needed to maintain glutathione (GSH) homeostasis that is dependent on betaine and its methyl group donation. We assess amino acids and thiol changes that occur during embryogenesis [12, 24 and 48 h post fertilization (hpf)] in VitE-sufficient (E+) and deficient (E-) embryos using two separate, novel protocols to quantitate changes using UPLC-MS/MS. Using partial least squares discriminant analysis, we found that betaine is a critical feature separating embryos by VitE status and is higher in E- embryos at all time points. Other important features include: glutamic acid, increased in E- embryos at 12 hpf; choline, decreased in E- embryos at 24 hpf; GSH, decreased in E- embryos at 48 hpf. By 48 hpf, GSH was significantly lower in E- embryos (P < 0.01), as were both S-adenosylmethionine (SAM, P < 0.05) and S-adenosylhomocysteine (SAH, P < 0.05), while glutamic acid was increased (P < 0.01). Since GSH synthesis requires cysteine (which was unchanged), these data suggest that both the conversion of homocysteine and the uptake of cystine via the Xc- exchanger are dysregulated. Our data clearly demonstrates the highly inter-related dependence of methyl donors (choline, betaine, SAM) and the methionine cycle for maintenance of thiol homeostasis. Additional quantitative flux studies are needed to clarify the quantitative importance of these routes.

Vitamin B Supplementation and Nutritional Intake of Methyl Donors in Patients with Chronic Kidney Disease: A Critical Review of the Impact on Epigenetic Machinery.

Cardiovascular morbidity and mortality are several-fold higher in patients with advanced chronic kidney disease (CKD) and end-stage renal disease (ESRD) than in the general population. Hyperhomocysteinemia has undoubtedly a central role in such a prominent cardiovascular burden. The levels of homocysteine are regulated by methyl donors (folate, methionine, choline, betaine), and cofactors (vitamin B6, vitamin B12,). Uremia-induced hyperhomocysteinemia has as its main targets DNA methyltransferases, and this leads to an altered epigenetic control of genes regulated through methylation. In renal patients, the epigenetic landscape is strictly correlated with the uremic phenotype and dependent on dietary intake of micronutrients, inflammation, gut microbiome, inflammatory status, oxidative stress, and lifestyle habits. All these factors are key contributors in methylome maintenance and in the modulation of gene transcription through DNA hypo- or hypermethylation in CKD. This is an overview of the epigenetic changes related to DNA methylation in patients with advanced CKD and ESRD. We explored the currently available data on the molecular dysregulations resulting from altered gene expression in uremia. Special attention was paid to the efficacy of B-vitamins supplementation and dietary intake of methyl donors on homocysteine lowering and cardiovascular protection.

Using Differential Threshold Effects of Individual and Combined Periconceptional Methyl Donor Status on Maternal Genomic LINE-1 and Imprinted H19 DNA Methylation to Predict Birth Weight Variance in the Taiwan Pregnancy-Newborn Epigenetics (TPNE) Cohort Study.

BACKGROUND: Few studies have comprehensively examined the effect of methyl donor status on maternal DNA methylation and birth outcomes. OBJECTIVES: This study examined associations between periconceptional methyl donor status and genome-wide and specific imprinted gene methylation and fetal growth indices in the Taiwan Pregnancy-Newborn Epigenetics cohort. METHODS: Plasma folate, choline (free form), and betaine concentrations of the participants enrolled at 7-10 weeks of gestation were analyzed. DNA methylation at regulatory sequences of the imprinted H19 gene and genomic long interspersed nuclear element 1 (LINE-1) were measured in maternal lymphocytes using bisulfite/high-resolution melt polymerase chain reaction. Associations with birth weight (BW) were estimated through multiple regressions from 112 mother-newborn pairs. RESULTS: A nonlinear "L-shaped" relation and an inverse association between maternal plasma folate in T1 (mean ± SE: 17.6 ± 5.1 nmol/L) and lymphocytic LINE-1 methylation (ß: -0.49, P = 0.027) were characterized. After adjusting for LINE-1 methylation, individual maternal folate concentrations were positively associated with BW variance (ß = 0.24, P = 0.035), and the association was more pronounced in mothers with choline in T1 (mean ± SE: 5.4 ± 0.6 µmol/L; ß: 0.40, P = 0.039). Choline status of the mothers in T2 (mean ± SE: 7.2 ± 0.6 µmol/L) was inversely associated with LINE-1 methylation (ß: -0.43, P = 0.035), and a positive association was evident between T1 choline and H19 methylation (ß: 0.48, P = 0.011). After adjusting for epigenetic modification, maternal choline status predicted a positive association with BW (ß: 0.56, P = 0.005), but the effect was limited to mothers with high betaine concentrations in T3 (mean ± SE: 36.4 ± 8.8 µmol/L), depending on folate status. CONCLUSIONS: Our data highlight the differential threshold effects of periconceptional folate, choline, and betaine status on genomic LINE-1 and H19 DNA methylation and how their interplay has a long-term effect on BW variance.

A placebo-controlled trial of folic acid and betaine in identical twins with Angelman syndrome.

BACKGROUND: Angelman syndrome (AS) is a neurodevelopmental disorder that is caused by maternal genetic deficiency of a gene that encodes E6-AP ubiquitin-protein ligase (gene symbol UBE3A) mapping to chromosome 15q11-q13. AS leads to stiff and jerky gait, excess laughter, seizures, and severe intellectual disability. In some parts of the brain, the paternally inherited UBE3A gene is subject to genomic imprinting by the action of the UBE3A-antisense transcript (UBE3A-ATS) on the paternally inherited allele. Consequently, only the maternally inherited UBE3A gene is expressed in mature neurons. AS occurs due to deletions of the maternal 15q11 - 13 region, paternal uniparental disomy (UPD), imprinting center defects, mutations in the maternal UBE3A gene, or other unknown genetic malfunctions that result in a silenced maternal UBE3A gene in the specific imprinted regions of the brain. RESULTS: A potential treatment strategy for AS is to increase methylation of UBE3A-ATS to promote expression of the paternal UBE3A gene and thus ameliorate the clinical phenotypes of AS. We treated two sets of male identical twins with class I deletions with a 1 year treatment trial of either betaine and folic acid versus placebo. We found no statistically significant changes in the clinical parameters tested at the end of the 1 year trial, nor did we find any significant adverse events. CONCLUSIONS: This study tested the hypothesis that by increasing the methylation of the UBE3A-antisense transcript in Angelman syndrome to promote expression of the silenced paternal UBE3A gene we may ameliorate the clinical phenotypes of AS. We treated two sets of identical twins with placebo versus betaine and folic acid. Although this study represented a novel approach to treating Angelman syndrome, the differences in the developmental testing results was not significant. This paper also discusses the value of monozygotic twin studies in minimizing confounding variables and its utility in conducting small treatment studies. TRIAL REGISTRATION: NCT00348933 . Registered 6 July 2006.