Association of pre-eclampsia risk with maternal levels of folate, homocysteine and vitamin B12 in Colombia: A case-control study

Elevated Homocysteine Levels and Endothelial Dysfunction in Unexplained Recurrent Spontaneous Abortion

Background

Recurrent spontaneous abortion, a common condition in reproductive medicine, often arises from complex factors and lacks specific treatments. While studies have associated folate metabolism abnormalities with poor embryonic development, research on methionine metabolism, particularly homocysteine levels, has been limited.

Methods

In this study, we analyzed blood samples from women with RSA and those with normal pregnancies.

Results

We observed elevated homocysteine levels in women with RSA, which were correlated with increased total plasma microparticles, endothelial microparticles (EMPs), and free plasma DNA. Furthermore, we exposed human umbilical vein endothelial cells (HUVECs) to varying concentrations of homocysteine (0, 0.5, 1, 2, 4, 8 mmol/L). We found that higher homocysteine levels exacerbated its cytotoxic effects on HUVECs. Flow cytometry revealed that homocysteine compromised cell membrane integrity, enhanced membrane permeability, and promoted EMPs release. Our findings suggest that elevated homocysteine levels in women with RSA may induce significant endothelial cell apoptosis, leading to endothelial dysfunction and an increase in released microparticles and free DNA, potentially contributing to miscarriages.

Conclusion

This study may contribute to understanding and exploring the underlying mechanisms of unexplained recurrent spontaneous abortion (URSA).

Iron and folic acid supplementation compliance during pregnancy and its effect on post-pregnancy anaemia among reproductive-age women in East Africa

BACKGROUND

Despite the government's effort to reduce the prevalence of anaemia among reproductive-age women globally, it continues as a significant public health issue, especially in low- and middle-income countries. Iron-folic acid (IFA) supplementation is a widely used intervention to prevent anaemia, but compliance remains a major challenge. There is a lack of literature examining IFA supplementation compliance during pregnancy and its impact on preventing and controlling anaemia during post-pregnancy in the East Africa region.

OBJECTIVE

This study aims to investigate compliance with IFA supplementation during pregnancy and its impact on post-pregnancy anaemia among reproductive-age women in East Africa.

DESIGN

This study was designed as a cross-sectional survey.

METHODS

This study used data from 43,200 reproductive-age women from 2015 to 2022 demographic and health survey datasets. We used multilevel mixed-effect logistic regression analysis to identify associated factors with IFA supplementation compliance during pregnancy. Furthermore, a propensity score matching (PSM) analysis was used to determine the effect of IFA supplementation compliance on anaemia after pregnancy among women.

RESULTS

The level of compliance with IFA supplementation during pregnancy was 31.33% (95% confidence interval (CI): 30.89, 31.77), whereas the prevalence of anaemia among reproductive-age women was 32.08% (95% CI: 31.64, 32.52). Maternal education, the timing of antenatal care (ANC) visits, wanted index pregnancy (last pregnancy), wealth status, healthcare access, mass media exposure and ANC services from skilled healthcare providers were significantly associated with compliance with IFA supplementation among pregnant women. The PSM analysis indicated a significant positive association between IFA supplementation compliance during pregnancy and prevention of post-pregnancy anaemia among reproductive-age women, with an average treatment effect on the treated (ATT) of 25.55% (ATT = -0.2555, 95% CI: -0.3440, -0.1669, p < 0.0001).

CONCLUSION

Despite universal IFA supplementation, anaemia remains prevalent in East African countries due to low level of compliance with IFA supplementation. Targeting individual and socio-economic factors during IFA supplementation promotion helps to prevent anaemia after pregnancy. Further research is recommended to gain deeper insights.

Genetically predicted circulating concentrations of micronutrients and risk of hypertensive disorders of pregnancy: a Mendelian randomization study

PURPOSE

Epidemiological studies examining the association between circulating micronutrients and the risk of hypertensive disorders during pregnancy (HDP) have produced inconsistent results. Therefore, we conducted a Mendelian randomization (MR) analysis to evaluate the potential causal relationship between micronutrients and HDP.

METHODS

Nine micronutrients (beta-carotene, vitamin B6, vitamin B12, calcium, zinc, selenium, copper, folate, and phosphorus) were selected as the exposure factors. Summary data for gestational hypertension (14,727 cases and 196,143 controls) and preeclampsia/eclampsia (7212 cases and 174,266 controls) were extracted from the FinnGen consortium. The MR analysis employed the inverse variance weighted method and conducted a range of sensitivity analyses.

RESULTS

The inverse variance weighted method indicated no significant causal relationship between nine genetically predicted micronutrient concentrations and gestational hypertension, as well as preeclampsia/eclampsia. Sensitivity analyses suggested the absence of pleiotropy.

CONCLUSION

There is no strong evidence to support the causation between circulating micronutrients and hypertensive disorder during pregnancy.

Periconceptional Supplementation with Folic Acid or Multiple Micronutrients Containing Folic Acid and the Risk for Hypertensive Disorders in Pregnancy

OBJECTIVE

The aim of this study was to investigate the association between supplementation containing folic acid only (FAO) or multiple micronutrients containing folic acid and the risk for hypertensive disorders in pregnancy (HDP).

SUBJECTS AND METHODS

The retrospective cohort study was based on data from women who gave birth from 2016 to 2018 at Tongzhou Maternal and Child Health Care Hospital of Beijing, China. The outcomes were HDP diagnosed after the 20th week of pregnancy, including gestational hypertension (GH), preeclampsia, and eclampsia. Associations between supplementation patterns and HDP were estimated by Poisson loglinear regression models. Sensitivity analyses were based on prepregnancy body mass index (BMI) and maternal age.

RESULTS

Among the 25,866 women included in the study, periconceptional use of FA supplementation marginally reduced the risk for HDP (adjusted risk ratio [aRR] = 0.87, 95% confidence interval [CI] 0.73-1.04). Women who began FAO supplementation before conception had a lower risk for GH compared to those who began after conception (aRR = 0.59, 95% CI: 0.45-0.78). The risk for HDP also reduced among FAO users who began supplementation before conception with a normal prepregnancy BMI (aRR = 0.64, 95% CI: 0.49-0.84) and users ≥30 years old (aRR = 0.75, 95% CI: 0.58-0.98).

CONCLUSIONS

Periconceptional FAO supplementation may reduce the risk for HDP, especially GH. The protective effects are greater among women with a normal prepregnancy BMI and those ≥30 years old.

Association of Altered Ratio of Maternal Folic Acid and Vitamin B12 during Pregnancy with Newborn Birth Weight, Head Circumference, and Chest Circumference

OBJECTIVE

This study evaluated the effect of an altered ratio of maternal RBC folate (MRF) to serum vitamin B12 (MB12) on pregnancy and newborn outcomes.

METHODS

Blood samples were collected from pregnant women and the umbilical cord at the time of delivery. Estimations of RBC folate and serum vitamin B12 from maternal and cord blood samples and total homocysteine (HCY) were performed. Maternal and newborn anthropometric parameters like placental weight (PW), head circumference (HC), chest circumference (CC), and body weight (BW) were measured in offsprings after birth. We stratified the pregnant women into six groups (a) vitamin B12 normal and folic acid normal (BNFN)-control group, (b) vitamin B12 normal and folic acid elevated (BNFE), (c) vitamin B12 normal and folic acid deficient (BNFD), (d) vitamin B12 deficient and folic acid normal (BDFN), (e) vitamin B12 deficient and folic acid elevated (BDFE) and (f) vitamin B12 deficient and folic acid deficient (BDFD) based on their levels of RBC folate (MRF) and vitamin B12 (MB12). The expression of the one-carbon metabolism genes (methionine synthase (MS), glycine N-methyltransferase (GNMT), and cystathionine β-synthase (CBS) was also studied in placental tissue by using real-time PCR.

RESULTS

Cord blood RBC folate was significantly reduced in groups BDFE and BDFD as compared to the control group (BNFN). The cord blood vitamin B12 levels were also reduced in the BDFE group as compared to the BDFD. All the newborn parameters viz. PW, HC, CC, and BW, were reduced in the altered MRF/MB12 ratio (low & high vs. normal ratio). Total HCY was significantly elevated in the groups with (BDFE & BDFN) an imbalance of maternal RBC folate and serum vitamin B12 as compared to the control group. Downregulation of one-carbon metabolism genes like MS (p < 0.001), GNMT (p < 0.05), and CBS (p < 0.01) in placental tissue was observed in the high MRF/MB12 ratio group as compared to the normal ratio group. A strong positive correlation was also observed between MRF, MB12, and newborn parameters.

CONCLUSIONS

The altered ratio of folate to vitamin B12 in the maternal blood is associated with adverse growth and development of the newborn.

Assessment of blood one-carbon metabolism indexes during mid-to-late pregnancy in 397 Chinese pregnant women

OBJECTIVES

One-carbon metabolism (OCM) significantly influences fetal growth and neurodevelopment through transferring methyl group to biomolecules, during which folate, methionine, choline and betaine function as methyl donor nutrients, while vitamin B2, B6, B12 function as enzyme cofactors, and homocysteine (Hcy) and S-adenosyl methionine (SAM) are functional metabolites. This study aimed to assess blood OCM index levels and explore their relationships among Chinese pregnant women.

METHODS

Data were obtained from the baseline of the Mother-Child Nutrition and Health Cohort Study. Pregnant women, voluntarily recruited from September 2020 to June 2022 during antenatal examinations in five Chinese cities at 24-32 gestational weeks, provided fasting venous blood samples. Measurements included RBC and serum folate, serum vitamin B2, B6, B12, choline, betaine, methionine, total Hcy (tHcy), and plasma SAM. Sociodemographic characteristics and pregnancy-related conditions were collected via a self-designed questionnaire.

RESULTS

Of 397 participants, 82.6% were in mid-pregnancy (24-27 gestational weeks) and 17.4% were in late-pregnancy (28-32 gestational weeks). Serum folate, vitamin B6, and B12 deficiencies were 2.5, 1.3, and 8.3%, respectively. Elevated tHcy (≥10 μmol/L) was observed in 1.8% of pregnant women. Elderly pregnant women (aged 35 and above) exhibited significantly lower serum methionine levels (p < 0.05), while multiparous women had lower RBC folate levels (p < 0.05), and lower serum methionine and vitamin B12 levels (p < 0.10, not statistically significant). Partial correlation analysis revealed positive associations between RBC folate and cofactor vitamin B12 (r = 0.244, p < 0.05) in the folate cycle, as well as significant correlations between two methyl donor paths [serum folate was significantly related to serum choline (r = 0.172) and betaine (r = 0.193)]. As functional biomarkers of OCM, serum tHcy exhibited negative associations with RBC folate (β = -0.330, p < 0.05) and vitamin B6 (β = -0.317, p < 0.05), and plasma SAM displayed a positive association with serum betaine (β = 0.610, p < 0.05), while negatively associated with serum vitamin B6 (β = -0.181, p < 0.05).

CONCLUSION

The blood OCM exhibited imbalances during mid-to-late pregnancy, characterized by lower levels of folate, vitamin B6, and B12, alongside elevated tHcy levels. Adequate folate and vitamin B6 emerged as significant predictors of lower tHcy levels. Additionally, serum betaine showed a positive correlation with plasma SAM. This suggests the importance of not only ensuring sufficient folate but also optimizing other OCM-related nutrients throughout pregnancy.

An association of deficiencies in balanced dietary practices and inadequate iron and folic acid supplement's intake during pregnancy and increasing risk of pre-eclampsia or eclampsia among Indian women

Pre-eclampsia or eclampsia is a serious reproductive health problem which can cause maternal, fetal and neonatal morbidity and mortality worldwide. However till the notable reasons of it is not very clear at all. The main essence of the present study was to examine the association between dietary intake, iron and folic acid consumption during pregnancy and the chances of occurrences of pre-eclampsia or eclampsia among Indian women. A cross sectional observational study was performed by using NFHS-5 (2019-21) data. 190,797 ever married women aged between 15-49 years who had a live birth in the past five years preceding the survey were availed for this study. Multivariable logistic regression analysis was carried out to find out the association between dietary and supplementary intake and occurrences of eclampsia. About 3.6% of the sample women had pre-eclampsia or eclampsia. The results of the study indicated that the likelihood of the prevalence of pre-eclampsia or eclampsia was significantly higher among those women who did not take adequate diet and as well as not consumed iron and folic acid tablet or syrup for at least 90 days during pregnancy compared to those women who took adequate diet and iron and folic acid supplementation even after controlling some maternal, health and lifestyle, socio-economic and demographic characteristics. Integrated and quality ANC services can only ensure adequate nutritional intake in terms of healthy and balanced diet. So, quality ANC services and with this micronutrients intake could be an effective way to reduce the prevalence of pre-eclampsia or eclampsia.

Advances in Folic Acid Biosensors and Their Significance in Maternal, Perinatal, and Paediatric Preventive Medicine

Auxotrophic primates like human beings rely on exogenous dietary vitamin B9 supplementation to meet their metabolic demands. Folates play a crucial role in nucleotide synthesis and DNA methylation. Maternal folate deficiency causes several pregnancy-related complications, perinatal defects, and early childhood cognitive impairments. New evidence suggests excess FA is a potential risk factor resulting in unfavourable genomic and epigenomic alterations. Thus, it is essential to revisit the need to consistently monitor maternal folate levels during pregnancy. Yet, to date, no point-of-care folate-monitoring biosensor is commercially available. Here, we critically appraise the advances in folate biosensors to understand the translational gaps in biosensor design. Further, our review sheds light on the potential role of folate biosensors in strengthening maternal, perinatal, and child healthcare.

Decoding the Gene Regulatory Network of Muscle Stem Cells in Mouse Duchenne Muscular Dystrophy: Revelations from Single-Nuclei RNA Sequencing Analysis

The gene dystrophin is responsible for Duchenne muscular dystrophy (DMD), a grave X-linked recessive ailment that results in respiratory and cardiac failure. As the expression of dystrophin in muscle stem cells (MuSCs) is a topic of debate, there exists a limited understanding of its influence on the gene network of MuSCs. This study was conducted with the objective of investigating the effects of dystrophin on the regulatory network of genes in MuSCs. To comprehend the function of dystrophin in MuSCs from DMD, this investigation employed single-nuclei RNA sequencing (snRNA-seq) to appraise the transcriptomic profile of MuSCs obtained from the skeletal muscles of dystrophin mutant mice (DMDmut) and wild-type control mice. The study revealed that the dystrophin mutation caused the disruption of several long non-coding RNAs (lncRNAs), leading to the inhibition of MEG3 and NEAT1 and the upregulation of GM48099, GM19951, and GM15564. The Gene Ontology (GO) enrichment analysis of biological processes (BP) indicated that the dystrophin mutation activated the cell adhesion pathway in MuSCs, inhibited the circulatory system process, and affected the regulation of binding. The study also revealed that the metabolic pathway activity of MuSCs was altered. The metabolic activities of oxidative phosphorylation (OXPHOS) and glycolysis were elevated in MuSCs from DMDmut. In summary, this research offers novel insights into the disrupted gene regulatory program in MuSCs due to dystrophin mutation at the single-cell level.

Maternal Hyperhomocysteinemia as a Predictor of Placenta-Mediated Pregnancy Complications: A Two-Year Novel Study

Background Placenta-mediated pregnancy complications (PMPCs) are a significant contributor to adverse maternal and fetal outcomes. Though the exact cause of the array of pregnancy-related vascular disorders is still unknown, increased maternal serum homocysteine (Hct) levels have been linked to the pathophysiology. Hyperhomocysteinemia (HHct) has been strongly linked with the risk of developing PMPCs such as preeclampsia (PE), fetal growth restriction (FGR), intrauterine fetal death (IUFD), preterm births and placental abruption. Methodology The present observational study was carried out on 810 low-risk antenatal women in their early second trimester (13-20 weeks gestation age) in the department of obstetrics and gynecology of a tertiary care rural hospital to identify the significance of abnormally raised maternal serum Hct level in developing PMPCs. Results Of the 810 participants studied, 224 (27.65%) had raised Hct levels whereas the rest of the 586 (72.35%) participants had normal Hct levels. The mean Hct level of raised homocysteine group (18.59 ± 2.46 micromol/L) was substantially raised than the normal Hct group (8.64 ± 3.1 micromol/L). It was observed that women with elevated serum Hct levels developed PMPCs significantly more than women with normal serum Hct levels (p-value <0.05). Among HHct subjects, 65.18% developed PE, 34.38% had FGR, 28.13% had a preterm delivery, 4.02% had abruptio placentae and 3.57% had IUFD. Conclusions The focus of the current study is on an easy and quick intervention such as assessing the often-ignored levels of Hct during pregnancy that can help predict and prevent PMPCs. It also highlights the necessity for well-thought-out large-scale studies and trials to further examine the phenomena, as pregnancy may be the only time when rural women will have the opportunity to receive advice and to be tested for HHct.

The Association Between Serum Homocysteine Levels and Placenta-Mediated Complications: A Narrative Review

The most extremely unfavourable outcome of pregnancy is the death of the mother and newborn. Negative outcomes for mothers or babies can occur as a result of complications or issues during pregnancy, birth or the post-partum period. Early elevated maternal homocysteine (Hct) levels during pregnancy have been linked to altered placental development. There is evidence that suggests an elevated maternal blood Hct level is the new obstetrical risk factor, and the association between hyperhomocysteinemia (HHct) and numerous obstetrical problems was recently recognised. Hct is an essential amino acid, which contains sulphur and is formed from the metabolism of methionine. HHct has several known aetiologies, including genetic anomalies; a deficiency in folic acid, vitamin B6 and vitamin B12; hypothyroidism; old age; and renal illnesses. Vascular problems, coronary artery disease, atherosclerosis and embolic illnesses can all occur as a result of high blood levels of Hct. Hct levels are lower in normal pregnancies than it is in women who are not pregnant. Many pregnancy-related problems, including pre-eclampsia (PE), recurrent pregnancy loss (RPL), placental abruption, premature delivery and foetal growth restriction (FGR) have been connected to HHct in recent research. We looked for pertinent literature using a thorough and systematic search from PubMed, Medline, Embase, Cochrane Library, Google, etc., and articles that were published before August 2022 based on serum Hct levels and various placenta-mediated complications for this review. In this review, we described the synthesis and metabolism of Hct in humans, Hct levels at various phases of normal pregnancy and the association between Hct and placenta-mediated pregnancy complications. The outcomes discovered can help obstetricians increase the likelihood of a successful pregnancy in cases where placenta-mediated issues are present. Lowering Hct levels with a high dose of folic acid tablets during the subsequent pregnancy may be useful for women who experienced these difficulties in prior pregnancies as a result of HHct.

One-carbon metabolism-related nutrients intake is associated with lower risk of preeclampsia in pregnant women: a matched case-control study

Many studies have suggested that folate plays a role in preeclampsia (PE) risks, but few studies have assessed folate-related 1-carbon metabolism (OCM)-related nutrients with the risk of PE. We hypothesized that OCM-related nutrients are associated with PE. A 1:1 matched case-control study was conducted to explore the association between dietary OCM-related nutrients intake and the risk of PE in pregnant Chinese women. Four hundred and forty pairs of pregnant women with PE and hospital-based, healthy pregnant women, matched according to gestational week (±1 week) and age (±3 years), were recruited. Dietary intake was assessed using a validated 78-item semiquantitative food frequency questionnaire. Multivariate conditional logistic regression was used to estimate odds ratios (ORs) and 95% CIs. Restricted cubic splines were plotted to evaluate the dose-response relationship between dietary OCM-related nutrient intake and the risk of PE. Intake of folate, vitamin B₆, vitamin B₁₂, methionine, and total choline were inversely related to the risk of PE after adjustment for covariates (all P trend < .05). Adjusted ORs (95% CIs) for quartile 4 versus quartile 1 were 0.71 (0.55-0.93) for folate, 0.66 (0.50-0.87) for vitamin B₆, 0.68 (0.52-0.88) for vitamin B₁₂, 0.77 (0.60-0.81) for methionine, and 0.67 (0.51-0.87) for total choline. This study suggests that dietary OCM-related nutrients intake is associated with lower odds of PE in pregnant Chinese women.

High level of homocysteine is associated with pre-eclampsia risk in pregnant woman: a meta-analysis

OBJECTIVE

We aimed to investigate the correlation between blood homocysteine (Hcy) levels and pre-eclampsia (PE) risk in pregnant women.

METHODS

Related articles were searched using PubMed, Embase, and Web of Science databases. Methodological quality of included studies was evaluated using the Newcastle-Ottawa Quality Assessment Scale (NOS). Cochran's Q and I² tests were used to evaluate heterogeneity. Egger's test was used to evaluate publication bias. A sensitivity analysis was performed to test stability of the results using a one-by-one elimination method. Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) was used to assess certainty of evidence.

RESULTS

Nine studies (4384 PE and 26021 non-PE patients) were included in the meta-analysis. The methodology of them was of good quality, with NOS scores of 5-8. However, there was a significant heterogeneity among included studies. Therefore, the random effect model was generated and combined results suggested a significant association between increased level of Hcy in pregnant women and PE risk. Although a significant publication bias was found in the current study with a P value of 0.006 in the Egger test, sensitivity analysis showed that the combined results were stable and did not vary significantly from any single study. However, the GRADE evidence quality was very low, which may lower the recommendation of pooled results.

CONCLUSIONS

Increased levels of Hcy in maternal blood were significantly associated with the risk of PE, but low certainty of evidence need to be improved by more high-quality studies.

Dietary factors that affect the risk of pre-eclampsia

Pre-eclampsia affects 3%-5% of pregnant women worldwide and is associated with a range of adverse maternal and fetal outcomes, including maternal and/or fetal death. It particularly affects those with chronic hypertension, pregestational diabetes mellitus or a family history of pre-eclampsia. Other than early delivery of the fetus, there is no cure for pre-eclampsia. Since diet or dietary supplements may affect the risk, we have carried out an up-to-date, narrative literature review to assess the relationship between nutrition and pre-eclampsia. Several nutrients and dietary factors previously believed to be implicated in the risk of pre-eclampsia have now been shown to have no effect on risk; these include vitamins C and E, magnesium, salt, ω-3 long-chain polyunsaturated fatty acids (fish oils) and zinc. Body mass index is proportionally correlated with pre-eclampsia risk, therefore women should aim for a healthy pre-pregnancy body weight and avoid excessive gestational and interpregnancy weight gain. The association between the risk and progression of the pathophysiology of pre-eclampsia may explain the apparent benefit of dietary modifications resulting from increased consumption of fruits and vegetables (≥400 g/day), plant-based foods and vegetable oils and a limited intake of foods high in fat, sugar and salt. Consuming a high-fibre diet (25-30 g/day) may attenuate dyslipidaemia and reduce blood pressure and inflammation. Other key nutrients that may mitigate the risk include increased calcium intake, a daily multivitamin/mineral supplement and an adequate vitamin D status. For those with a low selenium intake (such as those living in Europe), fish/seafood intake could be increased to improve selenium intake or selenium could be supplemented in the recommended multivitamin/mineral supplement. Milk-based probiotics have also been found to be beneficial in pregnant women at risk. Our recommendations are summarised in a table of guidance for women at particular risk of developing pre-eclampsia.

Homocysteine metabolism as the target for predictive medical approach, disease prevention, prognosis, and treatments tailored to the person

Homocysteine (Hcy) metabolism is crucial for regulating methionine availability, protein homeostasis, and DNA-methylation presenting, therefore, key pathways in post-genomic and epigenetic regulation mechanisms. Consequently, impaired Hcy metabolism leading to elevated concentrations of Hcy in the blood plasma (hyperhomocysteinemia) is linked to the overproduction of free radicals, induced oxidative stress, mitochondrial impairments, systemic inflammation and increased risks of eye disorders, coronary artery diseases, atherosclerosis, myocardial infarction, ischemic stroke, thrombotic events, cancer development and progression, osteoporosis, neurodegenerative disorders, pregnancy complications, delayed healing processes, and poor COVID-19 outcomes, among others. This review focuses on the homocysteine metabolism impairments relevant for various pathological conditions. Innovative strategies in the framework of 3P medicine consider Hcy metabolic pathways as the specific target for in vitro diagnostics, predictive medical approaches, cost-effective preventive measures, and optimized treatments tailored to the individualized patient profiles in primary, secondary, and tertiary care.

Association between abnormal maternal serum levels of vitamin B12 and preeclampsia: a systematic review and meta-analysis

CONTEXT

Some evidence has shown an association between maternal vitamin B12 levels and the development of preeclampsia in pregnant women, but the relationship between preeclampsia and vitamin B12 is not clear.

OBJECTIVE

The aim of this systematic review was to compare serum vitamin B12 levels in women with preeclampsia with those in normotensive pregnant women.

DATA SOURCES

The PubMed/MEDLINE, Scopus, and Web of Science databases were searched up to August 2019, along with the reference lists of included articles.

STUDY SELECTION

The literature was searched for observational studies that investigated vitamin B12 levels in women with preeclampsia.

DATA EXTRACTION

Data were extracted independently by 2 authors. Data were pooled using a random-effects model.

RESULTS

Vitamin B12 levels in women with preeclampsia were significantly lower than those in healthy women (mean, -15.24 pg/mL; 95%CI, -27.52 to -2.954; P < 0.015), but heterogeneity between studies was high (I2 = 97.8%; P = 0.0103). Subgroup analyses based on folic acid supplementation, homocysteine concentrations, and gestational age at the time of sampling for vitamin B12 assessment did not identify the sources of heterogeneity.

CONCLUSIONS

Women with preeclampsia had significantly lower vitamin B12 concentrations than normotensive pregnant women.

A Novel Review of Homocysteine and Pregnancy Complications

Homocysteine (Hct) is a substance produced in the metabolism of methionine. It is an essential type of amino acid gained from the daily diet. Methylenetetrahydrofolate reductase (MTHFR) gene mutation is related to elevated total homocysteine (tHct) expressions, in particular, among women with low folate intake. Hyperhomocysteinemia (HHct) is caused by numerous factors, such as genetic defects, lack of folic acid, vitamin B₆ and B₁₂ deficiency, hypothyroidism, drugs, aging, and renal dysfunction. Increased Hct in peripheral blood may lead to vascular illnesses, coronary artery dysfunction, atherosclerotic changes, and embolic diseases. Compared to nonpregnant women, the Hct level is lower in normal pregnancies. Recent studies have reported that HHct was associated with numerous pregnancy complications, including recurrent pregnancy loss (RPL), preeclampsia (PE), preterm delivery, placental abruption, fetal growth restriction (FGR), and gestational diabetes mellitus (GDM). Besides, it was discovered that neonatal birth weight and maternal Hct levels were negatively correlated. However, a number of these findings lack consistency. In this review, we summarized the metabolic process of Hct in the human body, the levels of Hct in different stages of normal pregnancy reported in previous studies, and the relationship between Hct and pregnancy complications. The work done is helpful for obstetricians to improve the likelihood of a positive outcome during pregnancy complications. Reducing the Hct level with a high dosage of folic acid supplements during the next pregnancy could be helpful for females who have suffered pregnancy complications due to HHct.

The impact of micronutrient deficiency on pregnancy complications and development origin of health and disease

Due to the spread of the western style diet, which is characterized by high intake of processed food, micronutrients (vitamins and minerals) deficiency is increasing in the Japanese population of all ages and genders. During pregnancy, the elevated demand for micronutrients put pregnant women at even higher risk of micronutrients deficiency. Some micronutrients are relatively famous such that women with reproductive age are recommended to take folic acid supplementation for the prevention of neural tube defect. However, it is not generally known that folate is also important for fetal growth throughout the pregnancy course and for prevention of pregnancy complications, and that pregnant women should continue to take supplementation during pregnancy and lactation. The types of micronutrients and the duration of supplementation are both important factors to maintain normal pregnancies. This review focused on four micronutrients that are commonly deficient in Japanese pregnant women, folate, vitamin B12, vitamin D, calcium, and magnesium. The detrimental effects of homocysteine accumulation associated with the above micronutrient defects and its link to catechol-o-methyltransferase insufficiency are described. We also discussed possible molecular mechanisms of pregnancy complications and the development origin of health and disease (DOHaD) regarding micronutrient deficiencies from the point of view of one carbon metabolism.

Maternal one carbon metabolism and interleukin-10 &-17 synergistically influence the mode of delivery in women with Early Onset Pre-Eclampsia

OBJECTIVE

Studies on One Carbon Metabolism (OCM), Interleukins-10 &-17 (IL-10/-17) & βhCG in pre-eclampsia and its delivery outcome (preterm birth) reveal contradictory results, attributed to clinical heterogeneity (early/late onset pre-eclampsia) or preterm/term birth. Disturbed OCM also influences IL-10 &-17 during pregnancy. We sought to investigate the synergism between OCM and IL-10/-17 mediated immune-regulation through βhCG in Early onset pre-eclampsia (EO-PE) patients, delivering preterm, among North Indian women.

STUDY DESIGN

Case-control study with a total of 399 pregnant women (EO-PE delivering preterm = 199; Normotensives delivering at term = 200). Maternal genotypes & biochemical estimations along with fetal genotypes on subset (n = 72) pertaining to OCM and IL-10/-17 regulation were assessed.

MAIN OUTCOME MEASURES

Association of 1) maternal plasma levels with EO-PE 2) maternal and fetal genotypes with EO-PE. 3) Effect of Hyper-homocysteinemia (surrogate of disturbed OCM) on differential immune regulation (IL10,-17, βhCG) in EO-PE and mode of delivery.

RESULTS

Hyper-homocysteinemia posed an increased risk of three folds for EO-PE. Both, folate and B12 deficiencies were associated with elevated homocysteine in EO-PE. Further, MTHFR 677TT homozygotes was present only in EO-PE indicating its detrimental role. However, maternal IL17-197AA genotype showed decreased risk for EO-PE. Furthermore, elevated maternal plasma IL-17 along with elevated IL-10 & βhCG were observed in EO-PE. Taken together, altered homocysteine metabolism was associated with high IL10 in EO-PE; and was more pronounced in spontaneous vaginal deliveries as compared to induced/caesarean section deliveries.

CONCLUSIONS

We report homocysteine mediated IL-10 &17 dysregulation and its influence on mode of delivery in EO-PE, possibly through initiation of cervical ripening. Further, these could serve potential biomarkers of EO-PE & its delivery outcome among vulnerable populations with similar nutritional & genetic predispositions.

Predictive value of 4-Hydroxyglutamate and miR-149-5p on eclampsia

This research aimed at exploring the predictive value of 4-Hydroxyglutamate and miR-149-5p on eclampsia. Preeclampsia patients admitted to our hospital (n = 204), with 112 mild patients and 92 severe patients. Thereinto, pregnant women who underwent physical examination were regarded as a normal group (NG) (n = 100). Serum 4-Hydroxyglutamate levels and miR-149-5p in each group were detected. The serum 4-Hydroxyglutamate level in pregnant women in the NG was markedly lower than that in preeclampsia, while the miR-149-5p level was higher (p = 0.001). The serum 4-Hydroxyglutamate level in severe preeclampsia was higher than that in mild preeclampsia, while the miR-149-5p level was lower (p = 0.001). Partial thromboplastin time (APTT) and prothrombin time (PT) of preeclampsia patients were lower than those of the NG, while Fibrinogen (Fib) was higher (p = 0.001). With the aggravation of the condition of patients, PT, APTT decreased and Fib index increased. In preeclampsia patients, serum 4-Hydroxyglutamate was negatively correlated with PT and APTT, positively correlated with Fib content (p < 0.001); serum miR-149-5p was dramatically positively correlated with PT and APTT, negatively correlated with Fib content (p < 0.001). 4-Hydroxyglutamate and miR-149-5p were relevant to the occurrence time of preeclampsia; 4-Hydroxyglutamate, miR-149-5p and their combination could be used for preeclampsia diagnosis. According to the situation of newborn, they were divided into good and poor groups. The 4-Hydroxyglutamate level in the good group was lower than that in the poor group, while the miR-149-5p level was higher. The adverse prognosis of preeclampsia patients was predicted by 4-Hydroxyglutamate and miR-149-5p. 4-Hydroxyglutamate is highly expressed in preeclampsia, while miR-149-5p is low. Single and combined detection of 4-Hydroxyglutamate, miR-149-5p can be used for preeclampsia diagnosis and prediction.

Role of maternal nutrition and oxidative stress in placental telomere attrition in women with preeclampsia

Background:Maternal nutrition influences the growth and development of the fetus and influences pregnancy outcome. We have earlier demonstrated altered maternal nutrition and increased oxidative stress in women with preeclampsia. Oxidative stress is known to be associated with reduced telomere length and short telomere aggregates. Increased telomere attrition leads to increased cellular senescence and tissue ageing. Methods:The present review focuses on the role of maternal nutrition and oxidative stress in telomere attrition in preeclampsia. Results and Conclusion:Future studies need to examine the association between maternal nutritional status in early pregnancy, oxidative stress and telomere attrition in preeclampsia.

Maternal Hypertensive Disorders in Pregnancy and Postpartum Plasma B Vitamin and Homocysteine Profiles in a High-Risk Multiethnic U.S., Population

Background: Hypertensive disorders of pregnancy are a recognized risk factor of a woman's future cardiovascular risk. The potential role of micronutrients in mitigating hypertensive disorders is not fully understood. This study examined maternal postpartum plasma B vitamin profiles by hypertensive disorders of pregnancy in a high-risk multiethnic U.S. population. Materials and Methods: The analyses included 2584 mothers enrolled within 3 days postpartum at the Boston Medical Center. Hypertensive disorders of pregnancy included gestational hypertension and pre-eclampsia disorders (pre-eclampsia, eclampsia, hemolysis, elevated liver enzymes, and/or low platelets syndrome) as documented in the medical records. Plasma folate, vitamin B12, and homocysteine levels were measured in blood samples collected at enrollment. Kernel density plots and multivariable regressions were used to examine the relationship between hypertensive disorders and postpartum B vitamin profiles. Results: Of the 2584 mothers, 10% had pre-eclampsia disorders that were associated with significantly lower plasma folate (adjusted beta coefficient (aβ): -0.10; 95% CI: -0.22 to -0.06) and increased homocysteine (aβ: 0.08; 95% CI: 0.04-0.13), but not with vitamin B12 concentrations. These associations remained robust after adjusting for a range of pertinent covariables and were more pronounced in non-Hispanic Black women compared with other groups. However, gestational hypertension was not significantly associated with any postpartum biomarker. Conclusions: We found that pre-eclampsia disorders, but not gestational hypertension, was associated with lower folate and higher homocysteine levels postpartum, especially among Black mothers. This finding, if further confirmed, may have implications for postpartum care, including attention to maternal micronutrient status to reduce and prevent hypertensive disorders in pregnancy-associated consequences in subsequent pregnancies and lifespan. Registration date: July 25, 2017; Registry website: https://clinicaltrials.gov/ct2/show/NCT03228875.

Critical review of nutrition, blood pressure and risk of hypertension through the lifecycle: do B vitamins play a role?

Hypertension is the leading cause of preventable mortality worldwide, contributing to over 9 million deaths per annum, predominantly owing to cardiovascular disease. The association of obesity, physical inactivity and alcohol with elevated blood pressure (BP) is firmly established. Weight loss or other dietary strategies, such as the Dietary Approaches to Stop Hypertension (DASH) diet, have been shown to be effective in lowering BP. Additionally, specific nutrients are recognised to contribute to BP, with higher sodium intake linked with an increased risk of hypertension, while potassium is associated with a reduced risk of hypertension. Of note, emerging evidence has identified a novel role for one-carbon metabolism and the related B vitamins, particularly riboflavin, in BP. Specifically in adults genetically at risk of developing hypertension, owing to the common C677T polymorphism in MTHFR, supplemental riboflavin (co-factor for MTHFR) was shown in randomised trials to lower systolic BP by up to 13 mmHg. A BP response to intervention of this magnitude could have important clinical impacts, given that a reduction in systolic BP of 10 mmHg is estimated to decrease stroke risk by 40%. This review aims to explore the factors contributing to hypertension across the lifecycle and to critically evaluate the evidence supporting a role for nutrition, particularly folate-related B vitamins, in BP and risk of hypertension. In addition, gaps in our current knowledge that warrant future research in this area, will be identified.

Serum homocysteine and folate concentrations in early pregnancy and subsequent events of adverse pregnancy outcome: the Sichuan Homocysteine study

Background

Hyperhomocysteinemia may be a risk factor for endothelial dysfunction. Folate and vitamin B12 regulate the homocysteine metabolic process. This study aimed to evaluate the associations between subsequent events of adverse pregnancy outcome and early variables of homocysteine, folate, and vitamin B12 in pregnant women.

Methods

This multicenter, retrospective, case–control study involved 563 pregnant women with adverse pregnancy outcome and 600 controls. Adverse pregnancy outcomes included one or more of the following events: preeclampsia, preterm birth, low birth weight, and stillbirth. The associations between subsequent events of adverse pregnancy outcome and early variables of homocysteine, folate, and vitamin B12; metabolic parameters; inflammatory markers; anthropometrics; and lifestyle habits at 11–12 weeks of gestation were analyzed using the logistic regression model.

Results

Compared to the lower quartile homocysteine concentrations, the upper quartile homocysteine concentrations were associated with preeclampsia, preterm birth and low birth weight. On the contrary, the lower quartile folate concentrations were associated with preeclampsia, preterm birth and low birth weight compared with the upper quartile folate concentrations. The incidence of adverse pregnancy outcome increased progressively from the first to fourth homocysteine quartiles but decreased progressively from the first to fourth folate quartiles. After adjusting for confounding factors, multivariate logistic regression analysis showed that besides systolic blood pressure, diastolic blood pressure, body mass index and age, homocysteine (IV vs I quartile, aOR 5.89, 95% CI 4.08–8.51, P < 0.001), folate (IV vs I quartile, aOR 0.35, 95% CI 0.25–0.50, P < 0.001), folate supplementation (yes vs no, aOR 0.55, 95% CI 0.35–0.86, P = 0.010) during early pregnancy were independently associated with subsequent events of adverse pregnancy outcome, and vitamin B12 was rejected. Of these, the homocysteine revealed the highest odds ratio in all risk variables, and folate showed the lowest odds ratio in all protective variables.

Conclusions

Higher homocysteine concentration and lower folate level during early pregnancy were associated with adverse pregnancy outcome. However, no association was found between vitamin B12 and adverse pregnancy outcome. Supplementation with folate in early pregnancy may reduce adverse pregnancy outcome.

Evidence of a Role for One-Carbon Metabolism in Blood Pressure: Can B Vitamin Intervention Address the Genetic Risk of Hypertension Owing to a Common Folate Polymorphism?

Hypertension in adulthood is recognized as the leading risk factor contributing to mortality worldwide, primarily from cardiovascular disease, whereas hypertension in pregnancy leads to serious adverse fetal and maternal outcomes. This article explores the under-recognized role of one-carbon metabolism in blood pressure (BP) and the potential for folate-related B vitamins to protect against hypertension. Genome-wide association studies and clinical studies provide evidence linking the 677C→T polymorphism in the gene encoding methylenetetrahydrofolate reductase (MTHFR) with BP and increased risk of hypertension and hypertension in pregnancy. A novel role for riboflavin (the MTHFR cofactor) has recently emerged, however, with evidence from randomized trials that supplemental riboflavin can lower BP specifically in adults with the variant MTHFR 677TT genotype. Further studies are required to elucidate the biological mechanisms linking one-carbon metabolism with BP and explore the effect of riboflavin in modulating the genetic risk of hypertension in early and later life.