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Folate (vitamin B9) is widely accepted to protect against fetal neural tube defects. The main sources of dietary folate are folic acid-fortified foods and folic acid-containing dietary supplements. However, folic acid is inactive in the human body and must be converted by the liver into the active molecule 5-methyltetrahydrofolate (5-MTHF). 5-MTHF functions as a methyl donor in many metabolic reactions, including the conversion of homocysteine into methionine, the biosynthesis of glycine from serine, and the biosynthesis of DNA precursor molecules. Therefore, folate is fundamental for growth, especially in the embryonic and fetal stages. Prescription of folic acid to women in the preconception period and during pregnancy is a consolidated practice. However, it can pose health risks in certain conditions, such as megaloblastic anemia, where it will conceal megaloblastic anemia due to vitamin B12 deficiency and in cases of reduced hepatic transformation of folic acid (e.g. due to genetic variants or during some pharmacotherapies). Some of these risks can be avoided by supplementation with 5-MTHF rather than folic acid. Because 5-MTHF does not require activation, it is immediately available to mother and fetus and does not accumulate in blood like folic acid does in cases of reduced hepatic transformation. This paper reviews the advantages and disadvantages of folate supplementation with folic acid versus 5-MTHF, with a focus on maternal and fetal health. [ABSTRACT FROM AUTHOR]

Vascular complications of sickle cell anemia (SCA) are influenced by many factors. Elevated plasma homocysteine (Hcy) is supposed to be an independent risk factor and is either genetic or nutritional origin. The present study evaluated the plasma Hcy level, MTHFR C677T gene polymorphism, effect of folic acid (FA) supplementation' and hemato-biochemical parameters in SCA and their effect on the vaso-occlusive crisis (VOC) in SCA patients of an Asian-Indian haplotype population. One hundred twenty cases of SCA (HbSS) and 50 controls with normal hemoglobin(HbAA) were studied. It was found that the plasma Hcy level is significantly higher (p < 0.0001) in patients with SCA (22.41 ± 7.8 μmol/L) compared to controls (13.2 ± 4.4 μmol/L). Moreover, patients without FA supplementation had a significantly (p < 0.001) higher Hcy level (27 ± 7 μmol/L) compared to those with supplementation (17.75 ± 5.7 μmol/L). Turkey-Kramer multiple comparison tests show that there is a significant difference (p < 0.05) in HbF percent, hemoglobin (Hb), platelet count, serum bilirubin (direct:Bil-D and total:Bil-T), aspartate transaminase (AST), lactate dehydrogenase (LDH), and plasma Hcy levels between mild and severe VOC. Between moderate VOC and severe VOC, there was a significant difference (p < 0.05) in HbF%, Bil-D, AST, Hcy. Pearson correlation revealed that plasma Hcy had a significantly (p < 0.05) positive correlation with AST, serum bilirubin (indirect and total), LDH, jaundice, stroke, VOC per year, and hospitalization per year whereas it was inversely correlated with HbF percentage, Hb level, and FA treatment. In the study population, increased plasma Hcy level, hemolysis, and platelet activation were found to influence VOC in SCA. [ABSTRACT FROM AUTHOR]

Paraquat is an herbicide that is commonly used worldwide. Exposure to paraquat results in Parkinson's disease (PD)-like symptoms including dopaminergic cell loss. Nutrition has also been linked in the pathogenesis of PD, such as reduced levels of folic acid, a B-vitamin, and component of one-carbon metabolism. Within one-carbon metabolism, methylenetetrahydrofolate reductase (MTHFR) catalyzes the irreversible conversion of 5, 10-methylenetetrahydrofolate to 5-methyltetrahydrofolate. A polymorphism in MTHFR (677 C&→T) has been reported in 5%–15% of North American and European human populations. The MTHFR polymorphism is also prevalent in PD patients. The goal of this study was to investigate the impact of paraquat-induced PD-like pathology in the context of reduced levels of MTHFR. Three-month-old male Mthfr +/− mice, which model the MTHFR polymorphism observed in humans, were administered intraperitoneal injections of paraquat (10 mg/kg) or saline 6 times over 3 weeks. At the end of paraquat treatment, motor and memory function were assessed followed by collection of brain tissue for biochemical analysis. Mthfr +/– mice treated with paraquat showed impaired motor function. There was increased microglial activation within the substantia nigra (SN) of Mthfr +/− mice treated with paraquat. Additionally, all Mthfr +/− mice that were treated with paraquat showed increased oxidative stress within the dorsal striatum, but not the SN. The present results show that paraquat exposure increases PD-like pathology in mice deficient in one-carbon metabolism. [ABSTRACT FROM AUTHOR]

Abstract Attention Deficit and Hyperactivity Disorder (ADHD) is one of the most common psychiatric disorders in childhood and causes significant functional impairments in children. Behavioral genetic and molecular genetic studies have provided significant evidence in terms of highlighting the etiology of ADHD. Folate deficiency during pregnancy is an established risk factor for ADHD. Polymorphisms in the Methyltetrahydrofolate Reductase (MTHFR) encoding gene, such as A1298C and C667T, are associated with the decreased bioavailability of folate, and this condition can act like folate deficiency. In the literature, no study has investigated MTHFR polymorphisms in mothers of children with ADHD. Sixty-four children diagnosed with ADHD and their mothers as well as 40 healthy children and their mothers participated in this study. MTHFR polymorphisms were investigated in all participants. Comparison of the C677C and A1298C MTHFR polymorphisms in children with and without ADHD revealed no significant differences. We found that the maternal C677C_CT genotype counts, both observed and expected values, were significantly different from those based on Hardy-Weinberg Principle Analysis in the ADHD group. The most important result of this study was that maternal C677C MTHFR gene polymorphisms are significant risk factors in for ADHD, and we argue that children with ADHD are exposed to folate deficiency, even if their mothers received a sufficient amount of folate during pregnancy. This result also highlights one of the genetic factors of ADHD. Further studies should be performed to confirm this finding. Highlights • Attention Deficit and Hyperactivity Disorder (ADHD) is one of the most common psychiatric disorders in childhood. • ADHD is considered a neurodevelopmental disorder. • Polymorphisms in the Methyltetrahydrofolate Reductase (MTHFR) encoding gene can act like folate deficiency. • We found that the maternal C677C_CT genotype counts were significantly different in the ADHD group. • Children with ADHD can exposed to folate deficiency, even if a sufficient amount of folate is received during pregnancy. [ABSTRACT FROM AUTHOR]

Background: There has been an alarming rise in the incidence of coronary artery disease (CAD) in India especially involving the age group of less than 45 years. In recent past, various studies focused on hemostatic aspects of CAD, but could not determine the significance of thrombophilic molecular marker in combination. The study was undertaken to investigate the association of thrombophilia related molecular markers in young patients with CAD. Materials and Methods: Thirty diagnosed patients with CAD of either sex under 40 years were included. Thirty healthy age and sex matched control subjects without evidence of CAD formed the control group. Detailed history and clinical examination findings were recorded. In addition to routine investigations, polymerase chain reaction (PCR) based molecular analysis for Factor V Leiden (FVL), methyltetrahydrofolate reductase (MTHFR) gene, tumor necrosis factor receptor 2 (TNFR2) gene, and prothrombin gene mutation were carried out. Results: The mean age (± SD) was 36.86 ± 3.90 years in the patients. Smoking was the most prevalent risk factor. FVL, MTHFR and TNFR2 gene mutation were seen in nine (30%) patient. Three patients had presence of more than one mutation. FVL, MTHFR and TNFR2 gene mutation was found in 4 (13.3%), 3 (10%), and 5 (16.6%) patients respectively. Prothrombin gene mutation was not seen in any of the subjects. There was no significant difference in lipid profile, fibrinogen levels and CRP among the patients with mutation and patients without mutation. Conclusion: Almost one-third of the cases were positive for the various mutations in the study and the presence of at-least one or the other risk factor adds on to the risk of future thrombosis. There is a need to demonstrate or document these mutations in a larger group further based upon ethnicity and geographic distribution.

Hyperhomocysteinemia is considered a risk factor for atherosclerosis. Methyltetrahydrofolate reductase (MTHFR) gene mutation and low level of plasma vitamin B and folate could take part in the etiology of peripheral arterial disease (PAD). We examined whether plasma vitamin B and folate levels and MTHFR-C677T polymorphism are associated with the risk of PAD. The study comprised 293 patients (107 females, 186 males, mean age of 66 ± SEM0.7 years) and 293 sex-matched control subjects (mean age of 62 ± SEM0.8 years). We also determined plasma lipid profile, hs-CRP, creatinine, vitamin B, folate and total homocysteine (tHcy) for all patients and controls. Odds ratios were non-significant for different genotypes of MTHFR-C677T polymorphism. There was a significant lower level of vitamin B in PAD patients. 43 and 25 % of patient and control populations were in the lowest quartile of vitamin B (<188 pmol/L), respectively. Plasma level of vitamin B in the lowest quartile significantly increased tHcy level in PAD patients, and it was independent of plasma folate level. Low level of plasma vitamin B was independently associated with hyperhomocysteinemia in PAD patients. The prevalence of the MTHFR-C677T mutation was not significantly different in patients with PAD compared with controls. [ABSTRACT FROM AUTHOR]

Schizencephaly is an uncommon congenital malformation of neuronal migration characterized by a gray matter-lined cleft extending from the pial surface to the ependymal surface of the lateral ventricles. Its etiology is heterogeneous and consists of hereditary factors or destructive processes that occur during the second trimester of pregnancy. We report 2 cases with schizencephaly and thrombophilia caused by mutations of the methyltetrahydrofolate reductase and the factor V Leiden genes. Their clinical presentations included motor deficits and mild cognitive deficits. [ABSTRACT FROM AUTHOR]

Background and Purpose: Carotid dissection is a recognized cause of stroke. An association has been reported between carotid dissection and elevated homocysteine levels. Homocysteine levels are partly determined by a thermolibile form of methyltetrahydrofolate reductase (MTHFR) which has a common C677T single nucleotide polymorphism (SNP). We sought to undertake a comprehensive genetic meta-analysis of this SNP and its association with carotid dissection. Methods: All case-control studies evaluating MTHFR/C677T in carotid dissection were identified. Pooled odds ratios (ORs) with 95% confidence intervals (CIs) using both fixed and random effects were determined for both dominant and recessive genetic models. Analyses were also undertaken to compare the effects of the homogenous forms of MTHFR/C677T. Results: Four manuscripts analyzing a total of 420 individuals (183 cases and 237 controls) were identified. The pooled OR for the dominant MTHFR/T677 model was 1.36 (95% CI 0.89–2.08; p = 0.16) while the pooled OR for the recessive TT model was 1.07 (95% CI 0.61–1.89; p = 0.81). To ensure a subtle recessive effect was not being masked by the inclusion of the heterozygous genotype, comparison of the CC and TT genotypes in cases against controls was undertaken but no significant association was observed (OR 0.73; 95% CI 0.38–1.40; p = 0.34). Conclusions: Our data does not support an association between the MTHFR/C677T molecular variant and carotid dissection. As this SNP accounts for the majority of the genetic variance of homocysteine levels, our data suggests that homocysteine is unlikely to play a major role in this condition. Copyright © 2008 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Abstract: Introduction: Elevated plasma total homocysteine is a major risk for coronary artery disease (CAD). Methyltetrahydrofolate reductase (MTHFR) is a main regulatory enzyme in homocysteine metabolism; a common C677T mutation in the MTHFR gene results in decreased enzyme activity, and contributes to increased homocysteine levels and decreased folate levels. We investigated the frequency of MTHFR C677T alleles in a Korean population, determined the genotype-specific threshold levels of folate or vitamin B12, and investigated the relationship between the TT genotype and the risk of CAD. Materials and methods: We enrolled a study population of 163 CAD patients and 50 control subjects, and screened the MTHFR C677T polymorphism using real-time PCR with melting point analysis. Levels of plasma homocysteine, folate and vitamin B12 were also determined. We then defined the genotype-specific threshold values of folate and vitamin B12 required to keep homocysteine levels in a normal range for individuals of each MTHFR C677T genotype. Results: The frequency of the TT genotype was 18% in control subjects and 26% in patients group (P >0.05). Individuals homozygous for the TT genotype had significantly elevated homocysteine levels (P <0.05). The genotype-specific folate threshold level was significantly higher in TT individuals than in the CC or CT genotypes. The OR of individuals with low folate status and the TT genotype to estimate the relative risk of CAD was 2.2 and the OR of those with high folate status and the TT genotype was 1.5 (95% CI, 0.5–9.6 and 0.7–3.2, respectively). Conclusion: We were able to define a gene–nutrient interaction that shows a higher risk for CAD based on specific threshold folate levels required by different MTHFR C677T genotypes in a Korean population. [Copyright &y& Elsevier]

Background & Objectives: Vegetarianism may result in low vitamin B12 and acquired hyperhomocysteinemia leading to thrombotic conditions such as cerebral venous sinus thrombosis (CVST). The clinico-radiological presentation and outcome of patients with hyperhomocysteinemia may be different from those without, but there is a paucity of information. This study was undertaken to find out the relationship of homocysteine (Hcy) with vitamin B12, folic acid and methyltetrahydrofolate reductase (MTHFR) mutation in the patients with CVST, and compare clinico-radiological severity and outcome of patients with and without hyperhomocysteinemia., Methods: Ninety-six CVST patients in whom Hcy level was measured, were included, and their risk factors and neurological, magnetic resonance (MR) imaging and MR venography findings were noted. They were evaluated for prothrombotic conditions including Hcy, vitamin B12, folic acid and MTHFR 677C→T mutation. Three month outcome was categorized as death, poor and good., Results: Seventy three per cent patients had risk factors; hyperhomocysteinemia in 52.1 per cent, protein S deficiency in 47.8 per cent, protein C deficiency in 19.4 per cent, MTHFR 677C→T mutation in 30.7 per cent, antinuclear antibody 11 per cent, and Factor V Leiden mutation in two per cent each. Thirty two per cent patients with hyperhomocysteinemia had no other thrombotic cause, and 22 per cent of them had either vitamin B12 and or folic acid deficiency only. The patients with hyperhomocysteinemia more frequently had vitamin B12 deficiency (70 vs. 13%), MTHFR 677C→T mutation (47.5 vs. 9.1%) and superior sagittal sinus thrombosis (78 vs. 56.5%) than normal Hcy group. The clinico-radiological severity and outcome were similar., Interpretation & Conclusions: Hyperhomocysteinemia was an important correctable risk factor of CVST in patients from northern India, and majority of them had either low vitamin B12 level or MTHFR mutation., Competing Interests: None