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Biomolecules Jan 2022Methylation is an essential biochemical mechanism that is central to the transmission of life, and crucially responsible for regulating gametogenesis and continued... (Review)
Review
Methylation is an essential biochemical mechanism that is central to the transmission of life, and crucially responsible for regulating gametogenesis and continued embryo development. The methylation of DNA and histones drives cell division and regulation of gene expression through epigenesis and imprinting. Brain development and its maturation also depend on correct lipid methylation, and continued neuronal function depends on biogenic amines that require methylation for their synthesis. All methylation processes are carried out via a methyltransferase enzyme and its unique co-factor S-adenosylmethionine (SAM); the transfer of a methyl group to a target molecule results in the release of SAH (SA homocysteine), and then homocysteine (Hcy). Both of these molecules are toxic, inhibiting methylation in a variety of ways, and Hcy recycling to methionine is imperative; this is achieved via the one carbon cycle, supported by the folates cycle. Folate deficiency causes hyperhomocysteinaemia, with several associated diseases; during early pregnancy, deficiency interferes with closure of the neural tube at the fourth week of gestation, and nutraceutical supplementation has been routinely prescribed to prevent neural tube defects, mainly involving B vitamins, Zn and folates. The two metabolic pathways are subject to single nucleotide polymorphisms that alter their activity/capacity, often severely, impairing specific physiological functions including fertility, brain and cardiac function. The impact of three types of nutraceutical supplements, folic acid (FA), folinic acid (FLA) and 5 Methyl THF (MTHF), will be discussed here, with their positive effects alongside potentially hazardous secondary effects. The issue surrounding FA and its association with UMFA (unmetabolized folic acid) syndrome is now a matter of concern, as UMFA is currently found in the umbilical cord of the fetus, and even in infants' blood. We will discuss its putative role in influencing the acquisition of epigenetic marks in the germline, acquired during embryogenesis, as well as the role of FA in the management of cancerous disease.
Topics: Carbon Cycle; Dietary Supplements; Female; Folic Acid; Humans; Infant; Leucovorin; Mutation; Pregnancy; Tetrahydrofolates
PubMed: 35204698
DOI: 10.3390/biom12020197 -
JAMA Jan 2020Dietary supplements marketed for male fertility commonly contain folic acid and zinc based on limited prior evidence for improving semen quality. However, no large-scale... (Randomized Controlled Trial)
Randomized Controlled Trial
IMPORTANCE
Dietary supplements marketed for male fertility commonly contain folic acid and zinc based on limited prior evidence for improving semen quality. However, no large-scale trial has examined the efficacy of this therapy for improving semen quality or live birth.
OBJECTIVE
To determine the effect of daily folic acid and zinc supplementation on semen quality and live birth.
DESIGN, SETTING, AND PARTICIPANTS
The Folic Acid and Zinc Supplementation Trial was a multicenter randomized clinical trial. Couples (n = 2370; men aged ≥18 years and women aged 18-45 years) planning infertility treatment were enrolled at 4 US reproductive endocrinology and infertility care study centers between June 2013 and December 2017. The last 6-month study visit for semen collection occurred during August 2018, with chart abstraction of live birth and pregnancy information completed during April 2019.
INTERVENTIONS
Men were block randomized by study center and planned infertility treatment (in vitro fertilization, other treatment at a study site, and other treatment at an outside clinic) to receive either 5 mg of folic acid and 30 mg of elemental zinc (n = 1185) or placebo (n = 1185) daily for 6 months.
MAIN OUTCOMES AND MEASURES
The co-primary outcomes were live birth (resulting from pregnancies occurring within 9 months of randomization) and semen quality parameters (sperm concentration, motility, morphology, volume, DNA fragmentation, and total motile sperm count) at 6 months after randomization.
RESULTS
Among 2370 men who were randomized (mean age, 33 years), 1773 (75%) attended the final 6-month study visit. Live birth outcomes were available for all couples, and 1629 men (69%) had semen available for analysis at 6 months after randomization. Live birth was not significantly different between treatment groups (404 [34%] in the folic acid and zinc group and 416 [35%] in the placebo group; risk difference, -0.9% [95% CI, -4.7% to 2.8%]). Most of the semen quality parameters (sperm concentration, motility, morphology, volume, and total motile sperm count) were not significantly different between treatment groups at 6 months after randomization. A statistically significant increase in DNA fragmentation was observed with folic acid and zinc supplementation (mean of 29.7% for percentage of DNA fragmentation in the folic acid and zinc group and 27.2% in the placebo group; mean difference, 2.4% [95% CI, 0.5% to 4.4%]). Gastrointestinal symptoms were more common with folic acid and zinc supplementation compared with placebo (abdominal discomfort or pain: 66 [6%] vs 40 [3%], respectively; nausea: 50 [4%] vs 24 [2%]; and vomiting: 32 [3%] vs 17 [1%]).
CONCLUSIONS AND RELEVANCE
Among a general population of couples seeking infertility treatment, the use of folic acid and zinc supplementation by male partners, compared with placebo, did not significantly improve semen quality or couples' live birth rates. These findings do not support the use of folic acid and zinc supplementation by male partners in the treatment of infertility.
TRIAL REGISTRATION
ClinicalTrials.gov Identifier: NCT01857310.
Topics: Adolescent; Adult; DNA Fragmentation; Dietary Supplements; Female; Fertilization in Vitro; Folic Acid; Humans; Infertility, Male; Live Birth; Male; Middle Aged; Semen; Semen Analysis; Sperm Count; Treatment Failure; Young Adult; Zinc
PubMed: 31910279
DOI: 10.1001/jama.2019.18714 -
BMC Medicine Oct 2019Periconceptional folic acid prevents neural tube defects (NTDs), but it is uncertain whether there are benefits for offspring neurodevelopment arising from continued... (Randomized Controlled Trial)
Randomized Controlled Trial
Effect of continued folic acid supplementation beyond the first trimester of pregnancy on cognitive performance in the child: a follow-up study from a randomized controlled trial (FASSTT Offspring Trial).
BACKGROUND
Periconceptional folic acid prevents neural tube defects (NTDs), but it is uncertain whether there are benefits for offspring neurodevelopment arising from continued maternal folic acid supplementation beyond the first trimester. We investigated the effect of folic acid supplementation during trimesters 2 and 3 of pregnancy on cognitive performance in the child.
METHODS
We followed up the children of mothers who had participated in a randomized controlled trial in 2006/2007 of Folic Acid Supplementation during the Second and Third Trimesters (FASSTT) and received 400 μg/d folic acid or placebo from the 14th gestational week until the end of pregnancy. Cognitive performance of children at 7 years was evaluated using the Wechsler Preschool and Primary Scale of Intelligence (WPPSI-III) and at 3 years using the Bayley's Scale of Infant and Toddler Development (BSITD-III).
RESULTS
From a total of 119 potential mother-child pairs, 70 children completed the assessment at age 7 years, and 39 at age 3 years. At 7 years, the children of folic acid treated mothers scored significantly higher than the placebo group in word reasoning: mean 13.3 (95% CI 12.4-14.2) versus 11.9 (95% CI 11.0-12.8); p = 0.027; at 3 years, they scored significantly higher in cognition: 10.3 (95% CI 9.3-11.3) versus 9.5 (95% CI 8.8-10.2); p = 0.040. At both time points, greater proportions of children from folic acid treated mothers compared with placebo had cognitive scores above the median values of 10 (girls and boys) for the BSITD-III, and 24.5 (girls) and 21.5 (boys) for the WPPSI-III tests. When compared with a nationally representative sample of British children at 7 years, WPPSI-III test scores were higher in children from folic acid treated mothers for verbal IQ (p < 0.001), performance IQ (p = 0.035), general language (p = 0.002), and full scale IQ (p = 0.001), whereas comparison of the placebo group with British children showed smaller differences in scores for verbal IQ (p = 0.034) and full scale IQ (p = 0.017) and no differences for performance IQ or general language.
CONCLUSIONS
Continued folic acid supplementation in pregnancy beyond the early period recommended to prevent NTD may have beneficial effects on child cognitive development. Further randomized trials in pregnancy with follow-up in childhood are warranted.
TRIAL REGISTRATION
ISRCTN ISRCTN19917787 . Registered 15 May 2013.
Topics: Child; Child Development; Child, Preschool; Cognition; Dietary Supplements; Female; Folic Acid; Follow-Up Studies; Gestational Age; Humans; Male; Pregnancy; Pregnancy Trimester, First; Pregnancy Trimester, Second; Pregnancy Trimester, Third
PubMed: 31672132
DOI: 10.1186/s12916-019-1432-4 -
Mediators of Inflammation 2016Background/Aims. Low serum folate levels can alter inflammatory reactions. Both phenomena have been linked to Alzheimer's disease (AD), but the effect of folic acid on... (Randomized Controlled Trial)
Randomized Controlled Trial
Background/Aims. Low serum folate levels can alter inflammatory reactions. Both phenomena have been linked to Alzheimer's disease (AD), but the effect of folic acid on AD itself is unclear. We quantified folate supplementation's effect on inflammation and cognitive function in patients with AD over the course of 6 months. Methods. Patients newly diagnosed with AD (age > 60 years; n = 121; mild to severe; international criteria) and being treated with donepezil were randomly assigned into two groups with (intervention group) or without (control group) supplemental treatment with folic acid (1.25 mg/d) for 6 months. The Mini-Mental State Examination (MMSE) was administered to all patients at baseline and follow-up, and blood samples were taken before and after treatment. We quantified serum folate, amyloid beta (Aβ), interleukin-6 (IL-6), tumor necrosis factor α (TNFα), plasma homocysteine (Hcy), S-adenosylmethionine (SAM), S-adenosylhomocysteine (SAH), and the mRNA levels of presenilin (PS), IL-6, and TNFα in leukocytes. Data were analyzed using a repeated-measures mixed model. Results. The mean MMSE was slightly increased in the intervention group compared to that in the control group (P < 0.05). Posttreatment, plasma SAM and SAM/SAH levels were significantly higher (P < 0.05), while Aβ 40, PS1-mRNA, and TNFα-mRNA levels were lower in the intervention group than in the control group (P < 0.05). The Aβ 42/Aβ 40 ratio was also higher in the intervention group (P < 0.05). Conclusions. Folic acid is beneficial in patients with AD. Inflammation may play an important role in the interaction between folic acid and AD. This trial is registered with clinical trial registration number ChiCTR-TRC-13003246.
Topics: Adult; Aged; Aged, 80 and over; Alzheimer Disease; Female; Folic Acid; Humans; Inflammation; Male; Middle Aged; Single-Blind Method; Vitamin B 12
PubMed: 27340344
DOI: 10.1155/2016/5912146 -
Journal of Assisted Reproduction and... Aug 2018To evaluate the possibility of correcting metabolic defects in gametes and embryos due to methylene tetra hydrofolate reductase (MTHFR) isoforms C677T and A1298C, by...
PURPOSE
To evaluate the possibility of correcting metabolic defects in gametes and embryos due to methylene tetra hydrofolate reductase (MTHFR) isoforms C677T and A1298C, by supplementation with 5-methyl THF instead of synthetic folic acid. In these couples, high doses of folic acid lead to UMFA (un-metabolized folic acid) syndrome.
METHODS
Thirty couples with fertility problems lasting for at least 4 years, such as recurrent fetal loss, premature ovarian insufficiency, or abnormal sperm parameters, with two thirds of them having failed assisted reproductive technology (ART) attempts were included in this program. For all couples, at least one of the partners was a carrier of one of the two main MTHFR isoforms. Most of the women had been previously treated unsuccessfully with high doses of folic acid (5 mg/day), according to what is currently proposed in the literature. The couples carrying one of the isoforms were treated for 4 months with 5-MTHF, at a dose of 600 micrograms per day, before attempting conception or starting another attempt at ART. The duration of treatment corresponding to an entire cycle of spermatogenesis is approximately 74 days.
RESULTS
In this first series of 33 couples, one couple was not followed-up, and two are still currently under treatment. No adverse effects were observed. Thirteen of the couples conceived spontaneously, the rest needing ART treatment in order to achieve pregnancy. Only three couples have, so far, not succeeded.
CONCLUSION
The conventional use of large doses of folic acid (5 mg/day) has become obsolete. Regular doses of folic acid (100-200 μg) can be tolerated in the general population but should be abandoned in the presence of MTHFR mutations, as the biochemical/genetic background of the patient precludes a correct supply of 5-MTHF, the active compound. A physiological dose of 5-MTHF (800 μg) bypasses the MTHFR block and is suggested to be an effective treatment for these couples. Moreover, it avoids potential adverse effects of the UMFA syndrome, which is suspected of causing immune dysfunction and other adverse pathological effects such as cancer (especially colorectal and prostate).
Topics: Adult; Dietary Supplements; Dose-Response Relationship, Drug; Female; Folic Acid; Humans; Male; Methylenetetrahydrofolate Reductase (NADPH2); Pregnancy; Pregnancy Outcome; Protein Isoforms; Reproductive Techniques, Assisted; Spermatogenesis; Tetrahydrofolates
PubMed: 29882091
DOI: 10.1007/s10815-018-1225-2 -
Critical Reviews in Oncology/hematology Aug 2023Folate metabolism is a target for various chemotherapeutic drugs. Folate and its synthetic variant folic acid are B-vitamins. To what extent these vitamins impact... (Review)
Review
Folate metabolism is a target for various chemotherapeutic drugs. Folate and its synthetic variant folic acid are B-vitamins. To what extent these vitamins impact treatment tolerance in patients with cancer remains unclear. A systematic literature review was conducted on intake and status of folate and folic acid in relation to chemotherapy-induced toxicities in children and adults with cancer. A total of 6231 publications were identified, of which 40 publications met the inclusion criteria. In 12 out of 22 studies focusing on antifolates, a deficient folate status and lower folate and folic acid intake were associated with a higher risk of toxicities. In 8 out of 14 studies focusing on fluoropyrimidine treatments, a higher folate status and intake were associated with a higher risk of toxicities. These findings might explain interindividual differences in treatment tolerance and highlight the importance of evaluating nutritional status in oncology care.
Topics: Adult; Child; Humans; Folic Acid; Vitamin B Complex; Nutritional Status; Neoplasms; Antineoplastic Agents; Dietary Supplements
PubMed: 37353179
DOI: 10.1016/j.critrevonc.2023.104061 -
Nutrients Apr 2011The vitamin folate is recognized as beneficial health-wise in the prevention of neural tube defects, anemia, cardiovascular diseases, poor cognitive performance, and... (Review)
Review
The vitamin folate is recognized as beneficial health-wise in the prevention of neural tube defects, anemia, cardiovascular diseases, poor cognitive performance, and some forms of cancer. However, suboptimal dietary folate intake has been reported in a number of countries. Several national health authorities have therefore introduced mandatory food fortification with synthetic folic acid, which is considered a convenient fortificant, being cost-efficient in production, more stable than natural food folate, and superior in terms of bioavailability and bioefficacy. Other countries have decided against fortification due to the ambiguous role of synthetic folic acid regarding promotion of subclinical cancers and other adverse health effects. This paper reviews recent studies on folate bioavailability after intervention with folate from food. Our conclusions were that limited folate bioavailability data are available for vegetables, fruits, cereal products, and fortified foods, and that it is difficult to evaluate the bioavailability of food folate or whether intervention with food folate improves folate status. We recommend revising the classical approach of using folic acid as a reference dose for estimating the plasma kinetics and relative bioavailability of food folate.
Topics: Adolescent; Adult; Aged; Biological Availability; Clinical Trials as Topic; Diet; Edible Grain; Female; Folic Acid; Food, Fortified; Fruit; Humans; Legislation, Food; Male; Middle Aged; Neural Tube Defects; Nutritional Status; Vegetables
PubMed: 22254106
DOI: 10.3390/nu3040475 -
Nutrients Jan 2021Preconception folic acid supplement use is a well-known method of primary prevention of neural tube defects (NTDs). Obese women are at a higher risk for having a child... (Review)
Review
Preconception folic acid supplement use is a well-known method of primary prevention of neural tube defects (NTDs). Obese women are at a higher risk for having a child with a NTD. As different international recommendations on folic acid supplement use for obese women before and during pregnancy exist, this narrative review provides an overview of epidemiology of folate deficiency in obese (pre)pregnant women, elaborates on potential mechanisms underlying folate deficiency, and discusses considerations for the usage of higher doses of folic acid supplements. Women with obesity more often suffer from an absolute folate deficiency, as they are less compliant to periconceptional folic acid supplement use recommendations. In addition, their dietary folate intake is limited due to an unbalanced diet (relative malnutrition). The association of obesity and NTDs also seems to be independent of folate intake, with studies suggesting an increased need of folate (relative deficiency) due to derangements involved in other pathways. The relative folate deficiency, as a result of an increased metabolic need for folate in obese women, can be due to: (1) low-grade chronic inflammation (2) insulin resistance, (3) inositol, and (4) dysbiotic gut microbiome, which plays a role in folate production and uptake. In all these pathways, the folate-dependent one-carbon metabolism is involved. In conclusion, scientific evidence of the involvement of several folate-related pathways implies to increase the recommended folic acid supplementation in obese women. However, the physiological uptake of synthetic folic acid is limited and side-effects of unmetabolized folic acid in mothers and offspring, in particular variations in epigenetic (re)programming with long-term health effects, cannot be excluded. Therefore, we emphasize on the urgent need for further research and preconception personalized counseling on folate status, lifestyle, and medical conditions.
Topics: Dietary Supplements; Female; Folic Acid; Folic Acid Deficiency; Humans; Neural Tube Defects; Obesity; Preconception Care; Pregnancy
PubMed: 33498674
DOI: 10.3390/nu13020331 -
Maternal & Child Nutrition Dec 2018In order to inform large scale supplementation programme design, we review and summarize the barriers and enablers for improved coverage and utilization of iron and... (Review)
Review
In order to inform large scale supplementation programme design, we review and summarize the barriers and enablers for improved coverage and utilization of iron and folic acid (IFA) supplements by pregnant women in 7 countries in Africa and Asia. Mixed methods were used to analyse IFA supplementation programmes in Afghanistan, Bangladesh, Indonesia, Ethiopia, Kenya, Nigeria, and Senegal based on formative research conducted in 2012-2013. Qualitative data from focus-group discussions and interviews with women and service providers were used for content analysis to elicit common themes on barriers and enablers at internal, external, and relational levels. Anaemia symptoms in pregnancy are well known among women and health care providers in all countries, yet many women do not feel personally at risk. Broad awareness and increased coverage of facility-based antenatal care (ANC) make it an efficient delivery channel for IFA; however, first trimester access to IFA is hindered by beliefs about when to first attend ANC and preferences for disclosing pregnancy status. Variable access and poor quality ANC services, including insufficient IFA supplies and inadequate counselling to encourage consumption, are barriers to both coverage and adherence. Community-based delivery of IFA and referral to ANC provides earlier and more frequent access and opportunities for follow-up. Improving ANC access and quality is needed to facilitate IFA supplementation during pregnancy. Community-based delivery and counselling can address problems of timely and continuous access to supplements. Renewed investment in training for service providers and effective behaviour change designs are urgently needed to achieve the desired impact.
Topics: Africa; Asia; Dietary Supplements; Female; Folic Acid; Health Knowledge, Attitudes, Practice; Health Services Accessibility; Humans; Iron; Pregnancy; Prenatal Care; Primary Health Care
PubMed: 29271115
DOI: 10.1111/mcn.12532 -
The American Journal of Clinical... Nov 2013Childhood asthma has become a critical public health problem because of its high morbidity and increasing prevalence. The impact of nutrition and other exposures during... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Childhood asthma has become a critical public health problem because of its high morbidity and increasing prevalence. The impact of nutrition and other exposures during pregnancy on long-term health and development of children has been of increasing interest.
OBJECTIVE
We performed a systematic review and meta-analysis of the association of folate and folic acid intake during pregnancy and risk of asthma and other allergic outcomes in children.
DESIGN
We performed a systematic search of 8 electronic databases for articles that examined the association between prenatal folate or folic acid exposure and risk of asthma and other allergic outcomes (eg, allergy, eczema, and atopic dermatitis) in childhood. We performed a meta-analysis by using a random-effects model to derive a summary risk estimate of studies with similar exposure timing, exposure assessment, and outcomes.
RESULTS
Our meta-analysis provided no evidence of an association between maternal folic acid supplement use (compared with no use) in the prepregnancy period through the first trimester and asthma in childhood (summary risk estimate: 1.01; 95% CI: 0.78, 1.30). Because of substantial heterogeneity in exposures and outcomes, it was not possible to generate summary measures for other folate indicators (eg, blood folate concentrations) and asthma or allergy-related outcomes; however, the preponderance of primary risk estimates was not elevated.
CONCLUSIONS
Our findings do not support an association between periconceptional folic acid supplementation and increased risk of asthma in children. However, because of the limited number and types of studies in the literature, additional research is needed.
Topics: Asthma; Child; Databases, Factual; Dermatitis, Atopic; Dietary Supplements; Eczema; Female; Folic Acid; Humans; Hypersensitivity; Pregnancy; Pregnancy Trimesters; Prenatal Exposure Delayed Effects; Randomized Controlled Trials as Topic; Risk Factors
PubMed: 24004895
DOI: 10.3945/ajcn.113.065623