The Association of Thyroid Function With Maternal and Neonatal Homocysteine Concentrations

An Evaluation of Food and Nutrient Intake among Pregnant Women in The Netherlands: A Systematic Review

Nutritional deficiencies during pregnancy can have serious consequences for the health of the (unborn) child. This systematic review provides an updated overview of the available food and nutrient intake data for pregnant women in The Netherlands and an evaluation based on the current recommendations. Embase, MEDLINE, and national institute databases were used. Articles were selected if they had been published since 2008 and contained data on food consumption, nutrient intake, or the status of healthy pregnant women. A qualitative comparison was made with the 2021 Dutch Health Council recommendations and reference values. A total of 218 reports were included, representing 54 individual studies. Dietary assessments were primarily performed via food frequency questionnaires. Protein, vitamin A, thiamin, riboflavin, vitamin B₆, folate, vitamin B₁₂, vitamin C, iron, calcium, and magnesium intakes seemed to be adequate. For folate and vitamin D, supplements were needed to reach the recommended intake. The reasons for concern are the low intakes of fruits, vegetables, and (fatty) fish, and the intakes of alcohol, sugary drinks, and salt. For several foods and nutrients, no or limited intake data were found. High-quality, representative, and recent data are needed to evaluate the nutrient intake of pregnant women in order to make accurate assessments and evaluations, supporting scientific-based advice and national nutritional policies.

Higher serum homocysteine and lower thyroid hormone levels in pregnant women are associated with neural tube defects

BACKGROUND

This study tested the hypothesis that abnormal maternal metabolism of both homocysteine and thyroid hormone network in pregnant women is associated with neural tube defects (NTDs) in a part of China with high NTD prevalence.

METHODS

A case-control study was performed between 2007 and 2009 in Lüliang Mountains, Shanxi Province. This study included 83 pregnant women who had fetuses with NTDs (cases) and 90 pregnant women with normal fetuses (controls). In addition, a cell model to illustrate the epidemiological findings was established.

RESULTS

Fetuses of mother who had both high total homocysteine (tHcy) and inadequate free thyroxine were 3 times more at risk of developing NTDs (adjusted odds ratio = 3.5; 95 % confidence interval = 1.2-10.4; cases vs. controls) using multivariate logistic regression models. Furthermore, biological interaction between metabolisms of Hcy and thyroid hormones was demonstrated in vitro. In homocysteine thiolactone of a metabolite of Hcy-treated mouse embryonic neural stem NE4C cells, genes (Bmp7, Ctnnb1, Notch 1, Gli2, and Rxra) related to both neural tube closure and thyroid hormone network were shown to be regulated by H3K79 homocysteinylation, which increased their expression levels.

CONCLUSIONS

The effect of maternal serum high tHcy on risk of developing NTDs is depended on maternal serum level of thyroxine. Meanwhile, a higher level of tHcy might also affect both maternal metabolism of thyroid hormone and neural tube closure in embryogenesis through homocysteinylation of histones.

Laboratory characteristics analysis of the efficacy of levothyroxine on subclinical hypothyroidism during pregnancy: a single-center retrospective study

To reassess the efficacy of levothyroxine on subclinical hypothyroidism (SCH, 4.0 mIU/L ≤ TSH (thyroid stimulating hormone) <10 mIU/L with normal free T4) during pregnancy. 165 levothyroxine-treated pregnant women experiencing SCH were screened. And controls were randomly selected using euthyroidism (EU) women, matched by age, gravidity, and parity in the EU group (n = 660). We evaluated laboratory characteristics and pregnancy outcomes during follow-ups. Compared with the EU group, the SCH group displayed higher inadequate maternal gestational weight gain, premature delivery, low birth weight offspring and infant offspring small for their gestational age. After levothyroxine treatment, the SCH group displayed lower total cholesterol, low-density lipoprotein levels, and higher serum homocysteine levels before delivery. Pregnant women with SCH still exhibit adverse pregnancy outcomes after levothyroxine treatment. Taken together, we believe that besides levothyroxine, vitamin B12 and folic acid could be added to the treatment of pregnant women with SCH. In addition, regular monitoring of blood sugar levels, lipid and homocysteine levels, and intervention gestational weight gain could alleviate the adverse effects of SCH on pregnancy outcomes.

Organochlorine pesticides exposure may disturb homocysteine metabolism in pregnant women

Maternal exposure to organochlorine pesticides (OCPs) has an adverse impact on maternal and fetal health, and excessive homocysteine is related to a variety of adverse pregnancy outcomes. Biomimetic studies suggest that OCPs interfere with folate-dependent pathways, but little evidence is available from studies with human subjects. This study explored whether exposure to OCPs interferes with the metabolism of homocysteine, which is folate dependent. A total of 313 pregnant women at 12-20 weeks gestation were recruited in Shanxi province, China, from 2014 to 2015. Plasma concentrations of 20 OCPs, including dichlorodiphenyltrichloroethane and metabolites (DDTs), hexachlorobenzene (HCB), and hexachlorocyclohexanes (HCHs), were analyzed by gas chromatography-mass spectrometry. Blood folate concentrations were analyzed by microbiological assay, and plasma homocysteine concentrations were determined by enzyme-linked immunosorbent assay. Information on demographics, lifestyle behaviors, and folic acid supplementation was collected by in-person interview. Of the women, 99% reported having taken folic acid supplements. Results of a logistic regression analysis showed that higher plasma levels of OCPs were associated with increased odds of higher plasma homocysteine after adjustment for potential confounding factors. Positive correlations were observed between plasma OCPs and plasma homocysteine concentrations: HCB (r = 0.176, p = 0.002), β-HCH (r = 0.172, p = 0.002), ρ,ρ'-DDE (r = 0.132, p = 0.020), ρ,ρ'-DDD (r = 0.161, p = 0.004), and ο,ρ'-DDT (r = 0.144, p = 0.011). Plasma concentrations of OCPs were negatively correlated with red blood cell (RBC) folate in the low-RBC-folate subgroup, but the correlations were not statistically significant. A positive correlation was observed between OCPs and homocysteine in the low-RBC-folate subgroup. These findings suggest that OCPs may disturb the folate-dependent homocysteine metabolism pathway.

Associations Between Maternal Thyroid Function and Birth Outcomes in Chinese Mother-Child Dyads: A Retrospective Cohort Study

OBJECTIVE

Although research suggests a close association between maternal thyroid function and birth outcomes, no clear conclusion has been reached. We aimed to explore this potential association in a retrospective cohort study.

METHODS

This study included 8985 mother-child dyads. The maternal serum free tetraiodothyronine (FT4), thyroid-stimulating hormone (TSH), and thyroid peroxidase antibody (TPO Ab) concentrations and birth outcome data were reviewed from medical records. Subjects with TPO Ab concentrations of >34 and ≤34 IU/ml were classified into the TPO Ab positivity (+) and TPO Ab negativity (-) groups, respectively.

RESULTS

Compared with subjects in the normal group (0.1 ≤ TSH < 2.5 mIU/L and TPO Ab-), those with TSH concentrations of 2.5-4.0 mIU/L and TPO Ab- had a 0.65-fold lower risk of low birth weight (LBW). In contrast, those with TSH concentrations of >4.0 mIU/L, regardless of the TPO Ab status, had a 2.01-fold increased risk of LBW. Subclinical hypothyroidism, regardless of the TPO Ab status, was associated with a 1.94-fold higher risk of LBW when compared with that in subjects with euthyroidism and TPO Ab-. No other significant associations were observed.

CONCLUSION

A maternal TSH concentration of 2.5-4.0 mIU/L was associated with a lower risk of LBW when combined with TPO Ab-, whereas subjects with a TSH concentration of >4.0 mIU/L had an increased risk of LBW. Subclinical hypothyroidism appears to be associated with a higher risk of LBW.

In Utero One-Carbon Metabolism Interplay and Metabolic Syndrome in Cardiovascular Disease Risk Reduction

The maternal obesogenic environment plays a role in programing the susceptibility of the fetus to postnatal non-alcoholic fatty liver disease (NAFLD), a risk factor for cardiovascular disease (CVD). NAFLD is a multisystem disease that is characterized by hepatic fat accumulation due in part to dysregulated energy metabolism network through epigenetic mechanisms such as DNA methylation. DNA methylation affects fetal programing and disease risk via regulation of gene transcription; it is affected by methyl donor nutrients such as vitamin B₁₂ , methionine, folic acid, vitamin B₆ , and choline. Although several studies have documented the role of several maternal methyl donor nutrients on obesity-induced NAFLD in offspring, currently, data are lacking on its impact on CVD risk as an endpoint. The aim of this paper is to use current knowledge to construct a postulation for the potential role of a comprehensive gestational methyl donor nutrients supplementary approach on the susceptibility of offspring to developing metabolic-syndrome-related cardiovascular complications.