Primary prevention of neural-tube defects and some other congenital abnormalities by folic acid and multivitamins: history, missed opportunity and tasks

Exposure to pesticides during pregnancy and the risk of neural tube defects: A systematic review

Exposure to pesticides during pregnancy has been associated with several serious congenital malformations, such as neural tube defects, therefore, is a cause for concern in terms of human health. This review aims to gather information related to maternal exposure during pregnancy and the risk of triggering neural tube defects in the offspring. The search strategy for the studies followed the PRISMA guidelines. We conducted a systematic search in the Science Direct, PubMed, Cochrane Library, Embase, Scopus, and Web of Science databases for all epidemiological studies that sought to associate exposure to pesticides during embryonic development with the risk of neural tube defects (NTDs). The keywords used were "pesticide", "herbicide", "congenital" and "neural". Of the 229 articles, 8 eligible ones (7 case-control and 1 cross-sectional) evaluated pesticide exposure in pregnancy. Different methods were used, including analysis of biological samples and questionnaires. The pesticides studied included insecticides, herbicides, fungicides, and nematicides. Insecticides were the most studied, with variations in concentrations between tissues and studies. Distinct levels of pesticides have been detected in maternal serum, placenta, and umbilical cord. Models were statistically adjusted for confounding factors, such as smoking and dietary supplement intakes. Concentrations were measured in different exposure windows (periconception and prenatal), related to NTDs such as anencephaly and spina bifida. Different data collection techniques, types of biological samples, and exposure windows were used, which made comparison difficult. The main pesticides studied included DDT, DDE, HCH, and endosulfan. Maternal serum showed the highest concentrations of pesticides, but detection in placental tissue and umbilical cord confirms embryonic exposure. Confounding variables were adjusted for in the analysis of the articles, but they may still contribute to the risk of NTDs. All the studies analyzed pesticide exposure and the relationship with NTDs. However, a more standardized survey would be ideal for better comparisons.

Association between nutrient intake and female infertility: a study based on NHANES database

BACKGROUND

This study was designed to investigate the association between nutrients and female infertility.

METHODS

A cross-sectional study on 18-45 years of age reproductive-age women was conducted using the data from the National Health and Nutrition Examination Surveys (NHANES) for the periods 2013-2014 and 2015-2016. Multivariate logistic regression analysis was performed to evaluate the association between nutrients and female infertility. Subgroup analysis was applied to the body mass index (BMI). Results were summarised using an odds ratio (OR) with a 95% confidence interval (CI).

RESULTS

Of the total 1713 women, 204 women (11.91%) were infertile. The result demonstrated that higher intake of carbohydrate (OR: 0.46, 95% CI: 0.24-0.86, p = 0.018), vitamin A (OR: 0.44, 95% CI: 0.24-0.80, p = 0.009), vitamin C (OR: 0.48, 95% CI: 0.26-0.88, p = 0.020), magnesium (OR: 0.36, 95% CI: 0.17-0.76, p = 0.009), iron (OR: 0.43, 95% CI: 0.23-0.82, p = 0.012), lycopene (OR: 0.55, 95% CI: 0.33-0.91, p = 0.022), and total folate (OR: 0.38, 95% CI: 0.20-0.70, p = 0.003) were associated with a lower risk of female infertility. The subgroup analysis also reported that intakes of vitamin A, vitamin C, and lycopene were related to a lower risk of female infertility among women with a BMI being 18.5-24.9 kg/m2. Among women with BMI > 24.9 kg/m2, high intakes of magnesium, iron and total folate were associated with a decreased risk of female infertility.

CONCLUSIONS

The intake of several nutrients is associated with a decreased risk of female infertility. These findings provide insight into potentially modifiable lifestyle factors associated with female infertility.

Nutrition in Gynecological Diseases: Current Perspectives

Diet and nutrition are fundamental in maintaining the general health of populations, including women's health. Health status can be affected by nutrient deficiency and vice versa. Gene-nutrient interactions are important contributors to health management and disease prevention. Nutrition can alter gene expression, as well as the susceptibility to diseases, including cancer, through several mechanisms. Gynecological diseases in general are diseases involving the female reproductive system and include benign and malignant tumors, infections, and endocrine diseases. Benign diseases such as uterine fibroids and endometriosis are common, with a negative impact on women's quality of life, while malignant tumors are among the most common cause of death in the recent years. In this comprehensive review article, a bibliographic search was performed for retrieving information about nutrients and how their deficiencies can be associated with gynecological diseases, namely polycystic ovary syndrome, infertility, uterine fibroids, endometriosis, dysmenorrhea, and infections, as well as cervical, endometrial, and ovarian cancers. Moreover, we discussed the potential beneficial impact of promising natural compounds and dietary supplements on alleviating these significant diseases.

Folic acid prevents functional and structural heart defects induced by prenatal ethanol exposure

State-of-the-art biophotonic tools captured blood flow and endocardial cushion volumes in tiny beating quail embryo hearts, an accessible model for studying four-chambered heart development. Both hemodynamic flow and endocardial cushion volumes were altered with ethanol exposure but normalized when folic acid was introduced with ethanol. Folic acid supplementation preserved hemodynamic function that is intimately involved in sculpting the heart from the earliest stages of heart development.

Folic Acid Fortification Prevents Morphological and Behavioral Consequences of X-Ray Exposure During Neurulation

Previous studies suggested a causal link between pre-natal exposure to ionizing radiation and birth defects such as microphthalmos and exencephaly. In mice, these defects arise primarily after high-dose X-irradiation during early neurulation. However, the impact of sublethal (low) X-ray doses during this early developmental time window on adult behavior and morphology of central nervous system structures is not known. In addition, the efficacy of folic acid (FA) in preventing radiation-induced birth defects and persistent radiation-induced anomalies has remained unexplored. To assess the efficacy of FA in preventing radiation-induced defects, pregnant C57BL6/J mice were X-irradiated at embryonic day (E)7.5 and were fed FA-fortified food. FA partially prevented radiation-induced (1.0 Gy) anophthalmos, exencephaly and gastroschisis at E18, and reduced the number of pre-natal deaths, fetal weight loss and defects in the cervical vertebrae resulting from irradiation. Furthermore, FA food fortification counteracted radiation-induced impairments in vision and olfaction, which were evidenced after exposure to doses ≥0.1 Gy. These findings coincided with the observation of a reduction in thickness of the retinal ganglion cell and nerve fiber layer, and a decreased axial length of the eye following exposure to 0.5 Gy. Finally, MRI studies revealed a volumetric decrease of the hippocampus, striatum, thalamus, midbrain and pons following 0.5 Gy irradiation, which could be partially ameliorated after FA food fortification. Altogether, our study is the first to offer detailed insights into the long-term consequences of X-ray exposure during neurulation, and supports the use of FA as a radioprotectant and antiteratogen to counter the detrimental effects of X-ray exposure during this crucial period of gestation.

Neural tube defects: Different types and brief review of neurulation process and its clinical implication

Neural Tube Defects are the most typical congenital malformations, with almost 300,000 cases annually worldwide. The incidence varies amongst geographical ranges from 0.2 to up to 11 per 1000 live births. In India, incidence is reportedly higher in north than south and can be attributable to diet and genetic variances. Etiology is multifactorial. Severe forms of whitethorn are allied with syndromes. Primary neurulation and secondary neurulation are the most crucial steps in the formation and closure of the neural tube; any interruption can lead to mild to severe NTDs depending on the level of insult during embryogenesis. Various molecular and cellular events take place simultaneously for neural tube bending and closure of the neural tube. Neurological deficit in the newborn is contingent on the level of defect and severity of the structures affected. Survival of the newborn also depends on the severity of the lesion. Folic acid supplementation in all prospective mothers, preferably 4 weeks before conception and at least 12 weeks after conception, can prevent NTDs in folic responsive groups. But there is a significant number of other causes leading to neural tube defects apart from folic acid. Hydrocephalus is the commonest abnormality allied with NTDs in syndromic cases.

Maternal alcohol consumption and risk of offspring with congenital malformation: the Japan Environment and Children's Study

BACKGROUND

The association between fetal exposure to alcohol and congenital structural disorders remains inconclusive. The present study searched for relationships between maternal alcohol consumption during pregnancy and the risk of congenital malformations.

METHODS

We evaluated the fixed dataset of a large national birth cohort study including 73,595 mothers with a singleton live birth. Information regarding the alcohol consumption of mothers was obtained from self-reported questionnaires. Physicians assessed for 6 major congenital malformations (congenital heart defects [CHDs], male genital abnormalities, limb defects, cleft lip and/or cleft palate [orofacial clefts (OFC)], severe brain abnormalities, and gastrointestinal obstructions) up to 1 month after birth. Multiple logistic regression analysis was performed to identify associations between maternal alcohol consumption during pregnancy and each malformation.

RESULTS

The prevalence of maternal drinking in early pregnancy and until the second/third trimester was 46.6% and 2.8%, respectively. The onset of CHD was inversely associated with mothers who quit drinking during early pregnancy (OR 0.85, 95% CI 0.74-0.98). There was no remarkable impact of maternal drinking habit status on the other congenital malformations after adjustment for covariates.

CONCLUSIONS

Maternal alcohol consumption during pregnancy, even in early pregnancy, displayed no significant adverse impact on congenital malformations of interest.

IMPACT

This large-scale Japanese cohort study revealed that no teratogenic associations were found between maternal retrospective reports of periconceptional alcohol consumption and congenital malformations after adjustment for covariates. This is the first nationwide birth cohort study in Japan to assess the effect of maternal alcohol consumption during pregnancy on major congenital malformations. Our finding indicated that maternal low-to-moderate alcohol consumption during pregnancy, even in early pregnancy, displayed no significant adverse impact on congenital heart defects, male genital abnormalities, limb defects, orofacial clefts, severe brain abnormalities, or gastrointestinal obstructions.

Determinants of Neural Tube Defects among Newborns in Amhara Region, Ethiopia: A Case-Control Study

BACKGROUND

Worldwide, an estimated 300,000 neonates are born with neural tube defects (NTDs) each year. However, NTDs are underreported in Ethiopia though it causes substantial mortality, morbidity, disability, and psychological and economic cost in the country. Moreover, the factors attributed to NTDs were not addressed. Hence, this study intended to identify the determinants of neural tube defects in Amhara Region, Ethiopia.

METHODS

A case-control study design was conducted among 400 newborns (133 cases and 267 controls) who were born at randomly selected public hospitals. Cases were identified using the physician diagnosis of confirmed NTDs, and the two consecutive controls were selected using a simple random sampling technique. The data analysis was done using Stata 14.0. Variables with p value < 0.25 in the bivariate analysis were entered into the multivariable logistic regression model, and a corresponding 95% confidence interval was used to identify the predictors of NTDs.

RESULTS

In this study, fifty percent (48%) of the cases were contributed by anencephaly. After controlling the covariates, living in rural areas (AOR = 1.78: 95% CI 1.02, 3.11), being illiterate (AOR = 1.81: 95% CI 1.07, 4.61), being female newborn (AOR = 1.95: 95% CI 1.09, 3.50), having no ANC follow-up (AOR = 1.93: 95% CI 1.17, 5.04), and having a previous history of NTDs (AOR = 4.39: 95% CI 2.42, 7.96) were the risk factors for NTDs. However, being supplemented with folic acid or multivitamins before or during pregnancy (AOR = 0.37: 95% CI 0.21, 0.65), never having taken any substance during pregnancy (AOR = 0.42: 95% CI 0.21, 0.88), and being free from medical illnesses during pregnancy (AOR = 0.27: 95% CI 0.11, 0.69) were the protective factors of NTDs.

CONCLUSION

The study revealed different factors associated with NTDs among newborns in the region. Therefore, comprehensive preventive strategies focused on identified risk factors are needed at regional and national levels.

3D light-sheet assay assessing novel valproate-associated cardiotoxicity and folic acid relief in zebrafish embryogenesis

Precise in vivo toxicological assays to determine the cardiotoxicity of pharmaceuticals and their waste products are essential in order to evaluate their risks to humans and the environment following industrial release. In the present study, we aimed to develop the sensitive imaging-based cardiotoxicity assay and combined 3D light-sheet microscopy with a zebrafish model to identify hidden cardiovascular anomalies induced by valproic acid (VPA) exposure. The zebrafish model is advantageous for this assessment because its embryos remain transparent. The 3D spatial localization of fluorescence-labeled cardiac cells in and around the heart using light-sheet technology revealed dislocalization of the heart from the outflow tract in two-day-old zebrafish embryos treated with 50 μM and 100 μM VPA (P < 0.01) and those embryos exposed to 20 μM VPA presented hypoplastic distal ventricles (P < 0.01). These two observed phenotypes are second heart field-derived cardiac defects. Quantitative analysis of the light-sheet imaging demonstrated that folic acid (FA) supplementation significantly increased the numbers of endocardial and myocardial cells (P < 0.05) and the accretion of second heart field-derived cardiomyocytes to the arterial pole of the outflow tract. The heart rate increased in response to the cellular changes occurring in embryonic heart development (P < 0.05). The present study disclosed the cellular mechanism underlying the role of FA in spontaneous cellular changes in cardiogenesis and in VPA-associated cardiotoxicity. The 3D light-sheet assay may be the next-generation test to evaluate the risks of previously undetected pharmaceutical and environmental cardiotoxicities in both humans and animals.

Evidence for potential underestimation of clinical folate deficiency in resource-limited countries using blood tests

Although a low serum folate concentration is a useful biomarker of pure folate deficiency, the presence of vitamin B12 deficiency or hemolysis or both in individuals with low folate status predictably raises serum folate levels. Therefore, in resource-limited settings where dietary folate deficiency can coexist with vitamin B12 deficiency or malaria or both, the serum folate concentration can range from normal to high, leading to serious underestimation of tissue folate status. This review traces the genesis of an inappropriate overreliance on the serum folate concentration to rule out folate deficiency in vulnerable populations of women and children. Of significance, without due consideration of a chronically inadequate dietary folate intake, authors of influential studies have likely wrongly judged these populations to have an adequate folate status. Through repetition, this error has led to a dangerous entry into the contemporary medical literature that folate deficiency is rare in women and children. As a consequence, many millions of under-resourced women and children with mild to moderate tissue folate deficiency may have been deprived of folate replacement. This review uses historical documents to challenge earlier conclusions and re-emphasizes the need for contextual integration of clinical information in resource-limited settings.

Oral Health Status and Fertility Treatment Including IVF

Oral health is extremely important for the general wellbeing of the individual. From a number of research articles, it is established that there is a definitive connection between periodontal health and many systemic diseases, like type II diabetes, cardiovascular diseases and even preterm labor and low birth weight of babies. The significant rate of failure in the treatment of infertility and IVF (in vitro fertilization) even with multiple advancements in the last decade has made scientist take interest in newer parameters of health, an important one among them being periodontal health. From the limited number of studies available on the relationship between periodontitis and reproductive health, it can be inferred that periodontitis can act as a focus of infection leading to bacteremia which can lead to complications in conceiving naturally or through IVF in women. A limited number of studies have also reported an association between male factor infertility (MFI) and dental health status of men. Although more research is needed to understand and explore this connection, this article reviews the current literature available linking poor oral health to infertility and poor outcomes of IVF.

Reevaluation of Antioxidative Strategies for Birth Defect Prevention in Diabetic Pregnancies

Diabetes mellitus in early pregnancy is the most severe maternal disease that is counted for 10% of newborn infants with structural defects. With the rapid increases in the number of diabetic women in childbearing age, the birth defect rate is projected to elevate dramatically. Thus, prevention of embryonic malformations becomes an urgent task. Animal studies have revealed an involvement of oxidative stress in diabetic embryopathy and treatment with antioxidants can reduce embryonic abnormalities. However, the failure of clinical trials using free radical-scavenging antioxidants to alleviate oxidative stress-related diseases prompts researchers to reevaluate the strategy in birth defect prevention. Hyperglycemia also disturbs other intracellular homeostasis, generating aberrant conditions. Perturbed folding of newly synthesized proteins causes accumulation of unfolded and misfolded proteins in the lumen of the endoplasmic reticulum (ER). The ER under the stress activates signaling cascades, known as unfolded protein response, to suppress cell mitosis and/or trigger apoptosis. ER stress can be ameliorated by chemical chaperones, which promote protein folding. Hyperglycemia also stimulates the expression of nitric oxide (NO) synthase 2 (NOS2) to produce high levels of NO and reactive nitrogen species and augment protein nitrosylation and nitration, resulting in nitrosative stress. Inhibition of NOS2 using inhibitors has been demonstrated to reduce embryonic malformations in diabetic animals. Therefore, targeting ER and nitrosative stress conditions using specific agents to prevent birth defects in diabetic pregnancies warrant further investigations. Simultaneously targeting multiple stress conditions using combined agents is a potentially effective and feasible approach.

Connecting teratogen-induced congenital heart defects to neural crest cells and their effect on cardiac function

Neural crest cells play many key roles in embryonic development, as demonstrated by the abnormalities that result from their specific absence or dysfunction. Unfortunately, these key cells are particularly sensitive to abnormalities in various intrinsic and extrinsic factors, such as genetic deletions or ethanol-exposure that lead to morbidity and mortality for organisms. This review discusses the role identified for a segment of neural crest in regulating the morphogenesis of the heart and associated great vessels. The paradox is that their derivatives constitute a small proportion of cells to the cardiovascular system. Findings supporting that these cells impact early cardiac function raises the interesting possibility that they indirectly control cardiovascular development at least partially through regulating function. Making connections between insults to the neural crest, cardiac function, and morphogenesis is more approachable with technological advances. Expanding our understanding of early functional consequences could be useful in improving diagnosis and testing therapies.

Reduction in mortality and teratogenicity following simultaneous administration of folic acid and vitamin E with antiepileptic, antihypertensive and anti-allergic drugs

Aim:

The present study was designed to evaluate the teratogenic effects on breeding pattern in mice following administration of lamotrigine (LT) and levetiracetam (LV) and its combination with anti-hypertensive and anti-allergic drugs. Moreover, possibility of decrease in teratogenic effect was also evaluated upon simultaneous administration of these combinations with folic acid or vitamin E.

Materials and Methods:

The study was carried out on mature female mice housed in polycarbonate breeding cages. Drugs were administered continuously till the birth of neonates and pups were examined for any teratogenic potential of drugs.

Results:

The results of the study reveals that teratogenic effects of lamotrigine, methyldopa and loratadine (LTMLO) combination were seems to be reduced upon simultaneous administration with folic acid, while addition of vitamin E was found to be more effective in reducing the mortality rate of levetiracetam, methyldopa and loratadine combination.

Conclusion:

Teratogenic effects of LTMLO combination were better prevented by folic acid. However, further studies on large number of animals and humans are required before reaching to definite conclusion.