Expression of genes encoding enzymes involved in the one carbon cycle in rat placenta is determined by maternal micronutrients (folic acid, vitamin B12) and omega-3 fatty acids

Association of MTHFR (C677T, A1298C) and MTRR A66G polymorphisms with fatty acids profile and risk of neural tube defects

OBJECTIVE

This study aims to determine if 5,10-methylenetetrahydrofolate reductase (MTHFR C677T and A1298C) and methionine synthase reductase (MTRR A66G) gene polymorphisms were associated with fatty acid (FA) levels in mothers of fetuses with neural tube defects (NTDs) and whether these associations were modified by environmental factors.

METHODS

Plasma FA composition was assessed using capillary gas chromatography. Concentrations of studied FA were compared between 42 mothers of NTDs fetuses and 30 controls as a function of each polymorphism by the Kruskal-Wallis nonparametric test.

RESULTS

In MTHFR gene C677T polymorphism, cases with (CT + TT) genotype had lower monounsaturated FAs (MUFA) and omega-3 polyunsaturated FA (n-3 PUFA) levels, but higher omega-6 polyunsaturated FAs (n-6 PUFA) and omega-6 polyunsaturated FAs: omega-3 polyunsaturated FAs (n-6:n-3) ratio levels. In MTRR gene A66G polymorphism, cases with (AG + GG) genotype had lower MUFA levels, but higher PUFA and n-6 PUFA levels. Controls with (AG + GG) genotype had lower n-6 PUFA levels. In MTHFR gene C677T polymorphism, cases with smoking spouses and (CT + TT) genotype had lower MUFA and n-3 PUFA levels, but higher PUFA, n-6 PUFA, and n-6:n-3 ratio levels. Cases with (CT + TT) genotype and who used sauna during pregnancy had lower n-3 PUFA levels. In MTRR gene A66G polymorphism, cases with (AG + GG) genotype and who used sauna during pregnancy had higher PUFA and n-6 PUFA levels.

CONCLUSIONS

Further research is required to clarify the association of FA metabolism and (MTHFR, MTRR) polymorphisms with NTDs.

A narrative review on the role of folate-mediated one-carbon metabolism and its associated gene polymorphisms in posing risk to preeclampsia

Preeclampsia (PE) presents a major obstetrical problem for mother and fetus which is characterized by the onset of hypertension and proteinuria in formerly normotensive women. Altered folate-mediated one-carbon metabolism is one of the factors for PE development either due to nutritional insufficiencies such as folate deficiency or polymorphisms in genes that code for the key enzymes of the cycle. Commonly, there are four genes in the cycle whose polymorphisms have been described in relation to PE. These factors could cause elevation of homocysteine; the toxic metabolite, which subsequently leads to the development of PE. Sufficient levels of folate have been considered important during pregnancy and may reduce the risk of development of PE. This review aims at discussing genetic polymorphisms and nutritional deficiencies as probable predisposing factors and suggests considering fetal genotypes, varied ethnicities, and interaction of various other factors involved to render better conclusiveness to the present studies.

Cell death mechanisms and their roles in pregnancy related disorders

Autophagy and apoptosis are catabolic pathways essential for homeostasis. They play a crucial role for normal placental and fetal development. These cell death mechanisms are exaggerated in placental disorders such as preeclampsia, intrauterine growth restriction (IUGR) and gestational diabetes mellitus (GDM). Apoptosis is widely studied, highly controlled and regulated whereas; autophagy is an orderly degradation and recycling of the cellular components. Cellular senescence may be initiated by a variety of stimuli, including hypoxia, oxidative stress, reduction in survival signals and nutrition deprivation. Apoptosis is regulated by two types of pathways intrinsic and extrinsic. Extrinsic pathway is initiated by apoptosis inducing cells such as macrophages, natural killer cells whereas; intrinsic pathway is initiated in response to DNA damage, cell injury and lack of oxygen. In autophagy, the cell or organelles undergo lysosomal degradation. Placental apoptosis increases as the gestation progresses while autophagy plays a role in trophoblast differentiation and invasion. In pregnancy disorders like preeclampsia and IUGR, proapoptotic markers such as caspase 3, 8, BAX are higher and antiapoptotic markers like Bcl-2 are lower. In GDM, apoptotic markers are reduced resulting in increased placental mass and fetal macrosomia. Apoptosis in the pathological pregnancies is also influenced by the reduced levels of micronutrients and long chain polyunsaturated fatty acids resulting in disturbed placental biology. This chapter describes the role of various key molecular events involved in cellular senescence and the various factors influencing them. This will help identify future therapeutic strategies for better management of these processes.

Maternal vitamin D deficiency influences long-chain polyunsaturated fatty acids and pregnancy outcome in association with alterations in one-carbon metabolism

Preeclampsia is a pregnancy-specific disorder, leading to maternal and infant morbidity and mortality. Abnormal placentation has been reported in preeclampsia. Nutrients like vitamin D and long-chain polyunsaturated fatty acids (LCPUFA) are known to play a role in placental development. In an animal model, we have previously demonstrated that maternal vitamin D deficiency increases the thromboxane/prostacyclin ratio and contributes to inflammation and vasoconstriction. We hypothesize that maternal vitamin D status influences placental LCPUFA metabolism through alterations in one carbon metabolism in women with preeclampsia. To test this hypothesis, we recruited 69 normotensive control (NC) women and 50 women with preeclampsia. Women with preeclampsia had lower placental protein and mRNA levels of cystathionine-β-synthase (CBS), higher plasma malondialdehyde (MDA) levels and higher levels of arachidonic acid (AA) and total omega-6 fatty acids in the placenta. Women with preeclampsia also demonstrated higher placental mRNA levels of cyclooxygenase-2 (COX-2) as compared to NC women. Maternal 25(OH)D levels were negatively associated with maternal plasma MDA levels. Placental vitamin D receptor (VDR) levels were positively associated with CBS while maternal MDA levels were positively associated with serum levels of thromboxane-B2 (TXB2) levels. Our findings indicate that vitamin D deficiency increases oxidative stress through alterations in one carbon metabolism to influence pro-inflammatory omega-6 metabolic pathway in the placenta. This study demonstrates a possible mechanism through which vitamin D deficiency can result in an imbalance in the LCPUFA metabolites and contribute to placental inflammation and endothelial dysfunction in preeclampsia.

Brain delivery of supplemental docosahexaenoic acid (DHA): A randomized placebo-controlled clinical trial

BACKGROUND

Past clinical trials of docosahexaenoic Acid (DHA) supplements for the prevention of Alzheimer's disease (AD) dementia have used lower doses and have been largely negative. We hypothesized that larger doses of DHA are needed for adequate brain bioavailability and that APOE4 is associated with reduced delivery of DHA and eicosapentaenoic acid (EPA) to the brain before the onset of cognitive impairment.

METHODS

33 individuals were provided with a vitamin B complex (1 mg vitamin B12, 100 mg of vitamin B6 and 800 mcg of folic acid per day) and randomized to 2,152 mg of DHA per day or placebo over 6 months. 26 individuals completed both lumbar punctures and MRIs, and 29 completed cognitive assessments at baseline and 6 months. The primary outcome was the change in CSF DHA. Secondary outcomes included changes in CSF EPA levels, MRI hippocampal volume and entorhinal thickness; exploratory outcomes were measures of cognition.

FINDINGS

A 28% increase in CSF DHA and 43% increase in CSF EPA were observed in the DHA treatment arm compared to placebo (mean difference for DHA (95% CI): 0.08 µg/mL (0.05, 0.10), p<0.0001; mean difference for EPA: 0.008 µg/mL (0.004, 0.011), p<0.0001). The increase in CSF EPA in non-APOE4 carriers after supplementation was three times greater than APOE4 carriers. The change in brain volumes and cognitive scores did not differ between groups.

INTERPRETATION

Dementia prevention trials using omega-3 supplementation doses equal or lower to 1 g per day may have reduced brain effects, particularly in APOE4 carriers.

TRIAL REGISTRATION

NCT02541929.

FUNDING

HNY was supported by R01AG055770, R01AG054434, R01AG067063 from the National Institute of Aging and NIRG-15-361854 from the Alzheimer's Association, and MGH by the L. K. Whittier Foundation. This work was also supported by P50AG05142 (HCC) from the National Institutes of Health. Funders had no role in study design, data collection, data analysis, interpretation, or writing of the report.

Effect of folic acid combined with docosahexaenoic acid intervention on mild cognitive impairment in elderly: a randomized double-blind, placebo-controlled trial

PURPOSE

This study aimed to assess the effects of folic acid (FA) combined with a docosahexaenoic acid (DHA) intervention on the cognitive function and inflammatory cytokines in elderly subjects with mild cognitive impairment (MCI).

METHODS

This randomized, double-blind, placebo-controlled trial recruited 240 individuals with MCI in Tianjin, China, and randomly allocated into 4 groups: FA + DHA (FA 800 μg/d + DHA 800 mg/d), FA (FA 800 μg/d), DHA (DHA 800 mg/d), and placebo. Cognitive function, serum folate and homocysteine (Hcy), plasma DHA and inflammatory cytokines levels were measured at baseline and 6 months.

RESULTS

Daily oral FA, DHA and their combined use for 6 months significantly improved the full-scale intelligence quotient (FSIQ) and some subtests of Wechsler Adult Intelligence Scale compared to the placebo. The increases of FSIQ, arithmetic, picture completion scores in the FA group and picture completion, block design scores in the DHA group were significantly less than that in the FA combined DHA group (P < 0.05). Meanwhile, daily oral FA, DHA and their combined use for 6 months significantly decreased plasma inflammatory cytokines compared to the placebo. The changes of interleukin-1β levels in the FA group and interleukin-6 levels in the DHA group were significantly less than that in the FA + DHA group (P < 0.05).

CONCLUSIONS

Daily oral FA, DHA and their combined use for 6 months can significantly improve cognitive function and decrease plasma inflammatory cytokines in MCI individuals. The combination of FA and DHA was more beneficial than each individual nutrient on their own.

Longitudinal Changes of One-Carbon Metabolites and Amino Acid Concentrations during Pregnancy in the Women First Maternal Nutrition Trial

BACKGROUND

Maternal dietary restriction and supplementation of one-carbon (1C) metabolites can impact offspring growth and DNA methylation. However, longitudinal research of 1C metabolite and amino acid (AA) concentrations over the reproductive cycle of human pregnancy is limited.

OBJECTIVE

To investigate longitudinal 1C metabolite and AA concentrations prior to and during pregnancy and the effects of a small-quantity lipid-based nutrition supplement (LNS) containing >20 micronutrients and prepregnancy BMI (ppBMI).

METHODS

This study was an ancillary study of the Women First Trial (NCT01883193, clinicaltrials.gov) focused on a subset of Guatemalan women (n = 134), 49% of whom entered pregnancy with a BMI ≥25 kg/m2. Ninety-five women received LNS during pregnancy (+LNS group), while the remainder did not (-LNS group). A subset of women from the Pakistan study site (n = 179) were used as a replication cohort, 124 of whom received LNS. Maternal blood was longitudinally collected on dried blood spot (DBS) cards at preconception, and at 12 and 34 wk gestation. A targeted metabolomics assay was performed on DBS samples at each time point using LC-MS/MS. Longitudinal analyses were performed using linear mixed modeling to investigate the influence of time, LNS, and ppBMI.

RESULTS

Concentrations of 23 of 27 metabolites, including betaine, choline, and serine, changed from preconception across gestation after application of a Bonferroni multiple testing correction (P < 0.00185). Sixteen of those metabolites showed similar changes in the replication cohort. Asymmetric and symmetric dimethylarginine were decreased by LNS in the participants from Guatemala. Only tyrosine was statistically associated with ppBMI at both study sites.

CONCLUSIONS

Time influenced most 1C metabolite and AA concentrations with a high degree of similarity between the 2 diverse study populations. These patterns were not significantly altered by LNS consumption or ppBMI. Future investigations will focus on 1C metabolite changes associated with infant outcomes, including DNA methylation. This trial was registered at clinicaltrials.gov as NCT01883193.

Single Nucleotide Polymorphisms in PEMT and MTHFR Genes are Associated with Omega 3 and 6 Fatty Acid Levels in the Red Blood Cells of Children with Obesity

Polyunsaturated fatty acids (PUFAs) play important roles in health and disease. PUFA levels are influenced by nutrition and genetic factors. The relationship between PUFA composition in red blood cells (RBCs) and genetic variations involved in PUFA metabolism has not been investigated in children with obesity. This study evaluated the association between several genetic variations and PUFA levels in RBCs in children with obesity. One hundred ninety-six children with obesity (101 females, 95 males) were evaluated using anthropometric measurements, dietary intakes, plasma and RBC PUFA quantification, blood biochemistry, and 55 single nucleotide polymorphisms within 14 genes. phosphatidylethanolamine N-methyltransferase (PEMT) rs1109859 and methylenetetrahydrofolate reductase gene (MTHFR) rs4846052 genotypes were associated with PUFA levels in RBCs. PUFA intake did not influence the RBC eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) levels. Higher RBC DHA and EPA levels were observed for PEMT rs1109859 GG and GA genotypes versus the AA genotype. Higher levels of RBC DHA, EPA, arachidonic acid (ARA), and linoleic acid (LA) and were observed for MTHFR rs4846052 TT genotype versus TC and CC genotypes. Genetic variations in PEMT rs1109859 and MTHFR rs4846052 were associated with different PUFA levels in RBC membranes and are estimators for PUFA species in RBCs. Further research is needed to establish whether these genotype-specific alterations are specific to overweight children.

Maternal vitamin D deficiency increases the thromboxane/prostacyclin ratio through alterations in the one-carbon cycle in Wistar rats

This study aims to test the hypothesis that vitamin D deficiency can influence long-chain polyunsaturated fatty acid metabolism through alterations in the one-carbon cycle. Wistar rats (n = 8 per group) were given either a control (1,000 IU D3/kg diet) or a vitamin D deficient (VDD) (0 IU D3/kg diet) diet from pre-pregnancy to delivery. On day 20 of gestation, pregnant female rats were delivered by C-section to collect placenta and blood. VDD group demonstrated high serum parathyroid hormone, low serum phosphate, low plasma folate, higher plasma homocysteine, and higher plasma malondialdehyde levels (P < 0.05 for all) as compared to control. Lower protein levels of placental cystathionine-β-synthase enzyme (P < 0.05) were observed in the VDD group as compared to control. VDD group demonstrated higher placental mRNA levels of the enzymes phospholipase A₂ and cyclooxygenase-2 (P < 0.05 for both) as compared to control. Protein levels of the enzymes phospholipase A₂ and cyclooxygenase-2 were lower (P < 0.05 for both) in the VDD group as compared to the control group. The ratio of thromboxane B₂ and 6-keto prostaglandin F_1α in serum was higher (P < 0.05) in the VDD group as compared to control; although the serum levels of 6-keto prostaglandin F_1α and thromboxane B₂ were similar in both the groups. Our findings suggest that increased oxidative stress due to maternal vitamin D deficiency results in the imbalance between the vasoconstrictor (thromboxane B₂ ) and vasodilator (6-keto prostaglandin F_1α ) eicosanoids, which may lead to endothelial dysfunction and poor pregnancy outcome. © 2019 BioFactors, 45 (4):548-555, 2019.

Effects of micronutrients on placental function: evidence from clinical studies to animal models

Micronutrient deficiencies are common in pregnant women due to low dietary intake and increased requirements for fetal development. Low maternal micronutrient status is associated with a range of pregnancy pathologies involving placental dysfunction, including fetal growth restriction (FGR), small-for-gestational age (SGA), pre-eclampsia and preterm birth. However, clinical trials commonly fail to convincingly demonstrate beneficial effects of supplementation of individual micronutrients, attributed to heterogeneity and insufficient power, potential interactions and lack of mechanistic knowledge of effects on the placenta. We aimed to provide current evidence of relationships between selected micronutrients (vitamin D, vitamin A, iron, folate, vitamin B12) and adverse pregnancy outcomes, combined with understanding of actions on the placenta. Following a systematic literature search, we reviewed data from clinical, in vitro and in vivo studies of micronutrient deficiency and supplementation. Key findings are potential effects of micronutrient deficiencies on placental development and function, leading to impaired fetal growth. Studies in human trophoblast cells and rodent models provide insights into underpinning mechanisms. Interestingly, there is emerging evidence that deficiencies in all micronutrients examined induce a pro-inflammatory state in the placenta, drawing parallels with the inflammation detected in FGR, pre-eclampsia, stillbirth and preterm birth. Beneficial effects of supplementation are apparent in vitro and in animal models and for combined micronutrients in clinical studies. However, greater understanding of the roles of these micronutrients, and insight into their involvement in placental dysfunction, combined with more robust clinical studies, is needed to fully ascertain the potential benefits of supplementation in pregnancy.

Maternal one carbon metabolism through increased oxidative stress and disturbed angiogenesis can influence placental apoptosis in preeclampsia

Adequate maternal nutrition is critical for a healthy pregnancy outcome and poor maternal nutrition is known to be associated with pregnancy complications like preeclampsia. We have earlier demonstrated that there is an imbalance in the levels of micronutrients (folate and vitamin B₁₂) along with low levels of long chain polyunsaturated fatty acids (LCPUFA) and high homocysteine levels in women with preeclampsia. Homocysteine is known to be involved in the formation of free radicals leading to increased oxidative stress. Higher oxidative stress has been shown to be associated with increased apoptotic markers in the placenta. Preeclampsia is of placental origin and is associated with increased oxidative stress, disturbed angiogenesis and placental apoptosis. The process of angiogenesis is important for placental and fetal development and various angiogenic growth factors inhibit apoptosis by inactivation of proapoptotic proteins through a series of cellular signalling pathways. We propose that an altered one carbon cycle resulting in increased oxidative stress and impaired angiogenesis will contribute to increased placental apoptosis leading to preeclampsia. Understanding the association of one carbon cycle components and the possible mechanisms through which they regulate apoptosis will provide clues for reducing risk of pregnancy complications.

Increased intake of vitamin B12, folate, and omega-3 fatty acids to improve cognitive performance in offspring born to rats with induced hypertension during pregnancy

Vitamin B₁₂, folic acid, and docosahexaenoic acid levels are reported to be altered in women with preeclampsia.

Hypermethylated CpG sites in the MTR gene promoter in preterm placenta

AIM

Altered maternal one-carbon metabolism influences placental DNA methylation patterns and 'programs' the fetus for noncommunicable diseases in adult life.

EXPERIMENTAL PROCEDURES

Levels of plasma folate, vitamin B₁₂, homocysteine, mRNA and protein levels of MTHFR and MTR enzymes in placenta were compared among women delivering preterm (n = 83) and term (n = 75). MTR promoter CpG methylation was undertaken.

RESULTS

MTHFR and MTR mRNA levels were higher while protein levels were lower, and MTR CpG sites were hypermethylated in the preterm group, as compared with the term group. Methylated CpG sites were negatively associated with maternal plasma vitamin B₁₂ levels.

CONCLUSION

Study suggests a dysregulation of enzyme genes in remethylation arm of the one-carbon metabolism in placenta of women delivering preterm.

Altered metabolic homeostasis between vitamin D and long chain polyunsaturated fatty acids in preeclampsia

Sub-optimal maternal nutrition may result in pregnancy complications like preeclampsia. Preeclampsia is known to be of placental origin and a major cause of maternal morbidity and mortality worldwide. Our earlier studies suggest that altered metabolism of folic acid, vitamin B₁₂ and long chain polyunsaturated fatty acid (LCPUFAs) in the one carbon cycle increases homocysteine levels in preeclampsia. Recent reports indicate that vitamin D deficiency may also have a role in preeclampsia, although the mechanisms are unclear. A disturbed one carbon cycle can influence methylation patterns of various genes involved in placental development. Altered expression of cystathionine beta synthase (CBS) gene can result in hyperhomocystenemia. Higher homocysteine levels are known to increase reactive oxygen species (ROS) production which in turn leads to increased expression of phospholipase A2 (PLA2) and cyclooxygenase-2 (COX-2). Higher expression of PLA2 and COX-2 can influence the release of arachidonic acid (AA) from membrane phospholipid and result in increased conversion to thromboxane. Vitamin D [1,25(OH)₂D₃] is known to induce the CBS gene expression while it can suppress the oxidative stress-induced COX-2 up-regulation and thromboxane production. Based on this, we propose a novel hypothesis that a disturbed vitamin D and LCPUFA metabolism influence the regulation of the one carbon cycle which will trigger inflammation through oxidative stress in preeclampsia. This may lead to altered feto-placental growth and development in preeclampsia.

Organ-Specific Gene Expression Changes in the Fetal Liver and Placenta in Response to Maternal Folate Depletion

Growing evidence supports the hypothesis that the in utero environment can have profound implications for fetal development and later life offspring health. Current theory suggests conditions experienced in utero prepare, or "programme", the fetus for its anticipated post-natal environment. The mechanisms responsible for these programming events are poorly understood but are likely to involve gene expression changes. Folate is essential for normal fetal development and inadequate maternal folate supply during pregnancy has long term adverse effects for offspring. We tested the hypothesis that folate depletion during pregnancy alters offspring programming through altered gene expression. Female C57BL/6J mice were fed diets containing 2 mg or 0.4 mg folic acid/kg for 4 weeks before mating and throughout pregnancy. At 17.5 day gestation, genome-wide gene expression was measured in male fetal livers and placentas. In the fetal liver, 989 genes were expressed differentially (555 up-regulated, 434 down-regulated) in response to maternal folate depletion, with 460 genes expressed differentially (250 up-regulated, 255 down-regulated) in the placenta. Only 25 differentially expressed genes were common between organs. Maternal folate intake during pregnancy influences fetal gene expression in a highly organ specific manner which may reflect organ-specific functions.

Variable Methylation Potential in Preterm Placenta: Implication for Epigenetic Programming of the Offspring

Children born preterm are reported to be at increased risk of developing noncommunicable diseases in later life. Altered placental DNA methylation patterns are implicated in fetal programming of adult diseases. Our earlier animal studies focus on micronutrients (folic acid, vitamin B₁₂) and long-chain polyunsaturated fatty acids (LCPUFAs) that interact in the 1 carbon cycle, thereby influencing methylation reactions. Our previous studies in women delivering preterm show altered plasma levels of micronutrients and lower plasma LCPUFA levels. We postulate that alterations in the micronutrient metabolism may affect the regulation of enzymes, methionine adenosyltransferase ( MAT2A), and SAH-hydrolase ( AHCY), involved in the production of methyl donor S-adenosylmethionine (SAM), thereby influencing the methylation potential (MP) in the placenta of women delivering preterm. The present study, therefore, examines the mRNA, protein levels of enzymes ( MAT2A and AHCY), SAM, S-adenosylhomocysteine (SAH) levels, and global DNA methylation levels from preterm (n = 73) and term (n = 73) placentae. The enzyme messenger RNA (mRNA) levels were analyzed by real-time quantitative polymerase chain reaction, protein levels by enzyme-linked immunosorbent assay, and SAM-SAH levels by high-performance liquid chromatography. The mRNA levels for MAT2A and AHCY are higher ( P < .05 for both) in the preterm group as compared to the term group. S-Adenosylmethionine and SAH levels were similar in both groups, although SAM:SAH ratio was lower ( P < .05) in the preterm group as compared to the term group. The global DNA methylation levels were higher ( P < .05) in women delivering small for gestation age infants as compared to women delivering appropriate for gestation age infants at term. Our data showing lower MP in the preterm placenta may have implications for the epigenetic programming of the developing fetus.

Effect of vitamin B12 and omega-3 fatty acid supplementation on brain neurotrophins and cognition in rats: A multigeneration study

Vitamin B12 and omega-3 fatty acids are important nutrients required for neuronal functioning. We have demonstrated the beneficial effects of vitamin B12 and omega-3 fatty acid supplementation on brain neurotrophins and cognition in the first and second generation offspring. However, there is a need to examine if the effects are sustained in the third generation offspring. This study reports the effects of vitamin B12 and omega-3 fatty acid supplementation across three consecutive generations on brain neurotrophins like brain derived neurotrophic factor (BDNF); nerve growth factor (NGF) and cognitive performance in the third generation male offspring. Three successive generations of Wistar rats were assigned the following groups throughout pregnancy, lactation and adulthood: i) Control, ii) vitamin B12 deficient (BD), iii) vitamin B12 deficient + omega-3 fatty acid (BDO), iv) vitamin B12 supplemented (BS) and v) vitamin B12 supplemented + omega-3 fatty acid (BSO). The BD group demonstrated lower (p < 0.01) NGF in the cortex but not BDNF levels although the cognition was impaired (p < 0.01). In contrast, in the BDO group, higher NGF levels were observed in the hippocampus and animals demonstrated improved (p < 0.01) cognitive performance. Vitamin B12 supplementation showed comparable BDNF levels in the hippocampus while their levels were lower in the cortex as compared to the control (p < 0.05). These animals showed more reference and working memory errors (p < 0.01) as compared to the control group. A combined supplementation of vitamin B12 and omega-3 fatty acid showed higher (p < 0.01) levels of DHA and NGF in the hippocampus, higher BDNF in both hippocampus and cortex and improved cognitive performance. Our findings have implications for fortification of foods with vitamin B12 and omega-3 fatty acids in improving brain development.

Supplementation of maternal omega-3 fatty acids to pregnancy induced hypertension Wistar rats improves IL10 and VEGF levels

OBJECTIVES

Our recent study demonstrates the beneficial effect of a combined supplementation of vitamin B12, folic acid, and docosahexaenoic acid in reducing the severity of pregnancy induced hypertension (PIH). It is also known to be associated with angiogenic imbalance and inflammation. The current study examines whether the individual/combined supplementation of folic acid, vitamin B12 and omega-3 fatty acid during pregnancy can ameliorate the inflammatory markers and restore the angiogenic balance in a rat model of PIH.

MATERIALS AND METHODS

There were total of six groups, control and five treatment groups: PIH Induced; PIH+vitamin B12; PIH+folic acid; PIH+Omega-3 fatty acids and PIH+combined micronutrient supplementation (vitamin B12+folic acid+omega-3 fatty acids). Hypertension during pregnancy was induced using L- Nitroarginine methylester (L-NAME; 50mg/kg body weight/day). Dams were dissected at d20 of gestation and placental tissues were collected for further analysis.

RESULTS

Animals from the PIH induced group demonstrated lower (p<0.01 for both) IL-10 and VEGF levels as compared to control. However, PIH induction did not alter the protein levels of eNOS, IL-6, Flt and mRNA levels of VEGF and VEGFR-1/ Flt-1. Individual micronutrient supplementation of vitamin B12 and folate did not offer benefit. In contrast individual omega-3 fatty acid as well as combined micronutrient supplementation showed IL-10 and VEGF levels comparable to that of control.

CONCLUSION

Omega 3 fatty acid supplementation plays a key role in reducing inflammation in pregnancy induced hypertension.

Intrauterine Programming of Diabetes and Adiposity

The prevalence of diabetes and adiposity has increased at an alarming rate and together they contribute to the rise in morbidity and mortality worldwide. Genetic studies till date have succeeded in explaining only a proportion of heritability, while a major component remains unexplained. Early life determinants of future risk of these diseases are likely contributors to the missing heritability and thus have a significant potential in disease prevention. Epidemiological and animal studies show the importance of intrauterine and early postnatal environment in programming of the fetus to adverse metabolic outcomes and support the notion of Developmental Origins of Health and Disease (DOHaD). Emerging evidence highlights the role of epigenetic mechanisms in mediating effects of environmental exposures, which in certain instances may exhibit intergenerational transmission even in the absence of exposure. In this article, we will discuss the complexity of diabetes and increased adiposity and mechanisms of programming of these adverse metabolic conditions.

Vitamin B12 and omega-3 fatty acids together regulate lipid metabolism in Wistar rats

Our recent study indicates that maternal vitamin B12 and omega-3 fatty acid status influence plasma and erythrocyte fatty acid profile in dams. The present study examines the effects of prenatal and postnatal vitamin B12 and omega-3 fatty acid status on lipid metabolism in the offspring. Pregnant dams were divided into five groups: Control; Vitamin B12 deficient (BD); Vitamin B12 supplemented (BS); Vitamin B12 deficient group supplemented with omega-3 fatty acids (BDO); Vitamin B12 supplemented group with omega-3 fatty acids (BSO). The offspring were continued on the same diets till 3 month of age. Vitamin B12 deficiency increased cholesterol levels (p<0.01) but reduced docosahexaenoic acid (DHA) (p<0.05), liver mRNA levels of acetyl CoA carboxylase-1 (ACC-1) (p<0.05) and carnitine palmitoyltransferase-1 (CPT-1) (p<0.01) in the offspring. Omega-3 fatty acid supplementation to this group normalized cholesterol but not mRNA levels of ACC-1 and CPT-1. Vitamin B12 supplementation normalized the levels cholesterol to that of control but increased plasma triglyceride (p<0.01) and reduced liver mRNA levels of adiponectin, ACC-1, and CPT-1 (p<0.01 for all). Supplementation of both vitamin B12 and omega-3 fatty acid normalized triglyceride and mRNA levels of all the above genes. Prenatal and postnatal vitamin B12 and omega-3 fatty acids together play a crucial role in regulating the genes involved in lipid metabolism in adult offspring.

Beneficial effects of omega-3 fatty acids and vitamin B12 supplementation on brain docosahexaenoic acid, brain derived neurotrophic factor, and cognitive performance in the second-generation Wistar rats

In vegetarian population, vitamin B12 deficiency coexists with suboptimal levels of omega-3 fatty acids. Studies indicate a need for supplementation/fortification of vitamin B12 and omega-3 fatty acids to reduce the risk of brain disorders. We have described the effects of vitamin B12 and omega-3 fatty acid supplementation on brain development in F1 generation animals. The current study investigates the effects of vitamin B12 and omega-3 fatty acids supplementation on brain function and cognition. Pregnant Wistar rats were assigned the following groups: control, vitamin B12 deficient (BD), vitamin B12 deficient + omega-3 fatty acid (BDO), vitamin B12 supplemented (BS), vitamin B12 supplemented + omega-3 fatty acid (BSO). The same diets were continued for two generations. BDO group showed higher (P < 0.05) levels of BDNF (brain derived neurotrophic factor) and DHA (docosahexaenoic acid) in the cortex and hippocampus as compared with the BD group. The cognitive performance was also normalized in this group. BS showed comparable levels of DHA, BDNF (protein and mRNA), and CREB mRNA (cAMP response element-binding protein) to that of control group while Tropomyosin receptor kinase mRNA levels were higher. The combined vitamin B12 and omega-3 fatty acid supplementation further enhanced the levels of DHA (P < 0.05) and BDNF (P < 0.05) in the hippocampus and CREB mRNA (P < 0.01) in the cortex as compared with BS group. The cognitive performance of these animals was higher (P < 0.05) as compared with BS group. Our data indicates the beneficial effects of vitamin B12 and omega-3 fatty acid supplementation across two generations on brain development and function.

Maternal omega-3 fatty acids and micronutrients modulate fetal lipid metabolism: A review

It is well established that alterations in the mother's diet or metabolism during pregnancy has long-term adverse effects on the lipid metabolism in the offspring. There is growing interest in the role of specific nutrients especially omega-3 fatty acids in the pathophysiology of lipid disorders. A series of studies carried out in humans and rodents in our department have consistently suggested a link between omega-3 fatty acids especially docosahexaenoic acid and micronutrients (vitamin B12 and folic acid) in the one carbon metabolic cycle and its effect on the fatty acid metabolism, hepatic transcription factors and DNA methylation patterns. However the association of maternal intake or metabolism of these nutrients with fetal lipid metabolism is relatively less explored. In this review, we provide insights into the role of maternal omega-3 fatty acids and vitamin B12 and their influence on fetal lipid metabolism through various mechanisms which influence phosphatidylethanolamine-N-methyltransferase activity, peroxisome proliferator activated receptor, adiponectin signaling pathway and epigenetic process like chromatin methylation. This will help understand the possible mechanisms involved in fetal lipid metabolism and may provide important clues for the prevention of lipid disorders in the offspring.

Consequences of dietary methyl donor supplements: Is more always better?

Epigenetic mechanisms are now recognized to play roles in disease etiology. Several diseases increasing in frequency are associated with altered DNA methylation. DNA methylation is accomplished through metabolism of methyl donors such as folate, vitamin B12, methionine, betaine (trimethylglycine), and choline. Increased intake of these compounds correlates with decreased neural tube defects, although this mechanism is not well understood. Consumption of these methyl donor pathway components has increased in recent years due to fortification of grains and high supplemental levels of these compounds (e.g. vitamins, energy drinks). Additionally, people with mutations in one of the enzymes that assists in the methyl donor pathway (5-MTHFR) are directed to consume higher amounts of methyl donors to compensate. Recent evidence suggests that high levels of methyl donor intake may also have detrimental effects. Individualized medicine may be necessary to determine the appropriate amounts of methyl donors to be consumed, particularly in women of child bearing age.

The importance of MTHFR, MTR, MTRR and CSE expression levels in Caucasian women with preeclampsia

OBJECTIVE

Preeclampsia (PE) is a major cause of maternal and perinatal mortality and morbidity. The studies suggest that both polymorphisms and changes of expression in genes encoding enzymes involved in the methionine and homocysteine metabolism (MHM), such as methylenetetrahydrofolate, reductase (MTHFR), methionine synthase (MTR), methionine synthase reductase (MTRR) and cystathionine gamma-lyase (CSE), could play a role in the development of hypertension during pregnancy. The aim of the study was to determine the expression level of MTHFR, MTR, MTRR and CSE genes in the development of PE in Caucasian women.

STUDY DESIGN

The control group consisted of 74 healthy pregnant women and 90 patients with diagnosed pre-eclampsia. Total RNA was isolated from placenta and the mRNA level of examined genes was to determine using real-time PCR.

RESULTS

The expression level of MTHFR gene showed no statistically significant difference in the study group as compared to the control group. An increase of mRNA levels for MTR and CTH was observed by 124.7% (p<0.0001) and 26.6% (p>0.05), respectively. However, a decrease of placental expression was noted for MTRR by 50% in preeclamptic women as compared to control group (p<0.0001).

CONCLUSIONS

Our findings suggest that the elevated RNA expression of MTR in placenta of preeclamptic patients is probably results of a potential compensation mechanism of the MHM while elevated CSE expression indicates that homocysteine may be eliminated through the alternate transsulfuration pathway.