Elemental metabolomics in human cord blood: Method validation and trace element quantification

Dietary supplements, guideline alignment and biochemical nutrient status in pregnancy: Findings from the Queensland Family Cohort pilot study

In high-income nations, multiple micronutrient (MMN) supplementation during pregnancy is a common practice. We aimed to describe maternal characteristics associated with supplement use and daily dose of supplemental nutrients consumed in pregnancy, and whether guideline alignment and nutrient status are related to supplement use. The Queensland Family Cohort is a prospective, Australian observational longitudinal study. Maternal characteristics, nutrient intake from food and supplements, and biochemical nutrient status were assessed in the second trimester (n = 127). Supplement use was reported by 89% of participants, of whom 91% reported taking an MMN supplement. Participants who received private obstetric care, had private health insurance and had greater alignment to meat/vegetarian alternatives recommendations were more likely to report MMN supplement use. Private obstetric care and general practitioner shared care were associated with higher daily dose of supplemental nutrients consumed compared with midwifery group practice. There was high reliance on supplements to meet nutrient reference values for folate, iodine and iron, but only plasma folate concentrations were higher in MMN supplement versus nonsupplement users. Exceeding the upper level of intake for folic acid and iron was more likely among combined MMN and individual supplement/s users, and associated with higher plasma concentrations of the respective nutrients. Given the low alignment with food group recommendations and potential risks associated with high MMN supplement use, whole food diets should be emphasized. This study confirms the need to define effective strategies for optimizing nutrient intake in pregnancy, especially among those most vulnerable where MMN supplement use may be appropriate.

Multidimensional analysis of the essential elements in pregnant women's whole blood and characterization of maternal status by elemental pattern

BACKGROUND

During pregnancy, the fetus needs to obtain a lot of nutrients from the mother, but the micronutrient deficiencies in pregnancy are not clear at present, and there is no reliable basis for nutrient intake and supplement. The purpose of this study was to understand the levels of essential elements in whole blood of pregnant women during various pregnancy stages at different ages and in different regions, to evaluate the deficiency of essential elements in Chinese pregnant women, and to explore the feasibility of using the elemental pattern to characterize maternal status.

METHODS

Whole blood samples of 11222 healthy pregnant women enrolled in different areas of China from Jan-Dec 2019, were analyzed for concentrations of six essential elements including Mn, Cu, Zn, Ca, Mg, and Fe, using the inductively coupled plasma mass spectrometer. A retrospective comparative study during different pregnancy periods at different ages and in different regions in whole blood essential elements content from non-pregnant normal women and pregnant normal women was developed using multivariate statistical analysis. Principal component analysis evaluation elemental pattern was used to characterize pregnancy status of pregnant women.

RESULTS

In general, the levels of six essential elements in whole blood of pregnant women can satisfy the needs of normal physiological activities. With the development of pregnancy, the contents of Cu and Mn increased, while the contents of Fe and Mg decreased, and the contents of Zn and Ca have no noteworthy change. At the same gestation stage, the Cu content in whole blood of elderly pregnant women was higher. There were some differences in whole blood essential elements content of pregnant women in different regions. Principal component analysis and heat map analysis showed the feasibility of using bioinformatics research strategies to identify different pregnancies.

CONCLUSIONS

There are differences in the content of whole blood essential elements of women at different stages of pregnancy in different regions. It was found that there was no obvious deficiency in whole blood essential elements levels of pregnant women in recent years. The pattern of essential elements has a certain application potential in the evaluation of pregnancy and pregnant women's health status.

Chemical element concentrations in cord whole blood and the risk of preterm birth for pregnant women in Guangdong, China

Maternal exposure to chemical elements, including essential and non-essential elements, have been found to be associated with preterm births (PTB). However, few studies have measured element concentrations in cord whole blood, which reflects activity at the maternal-fetal interface and may be biologically associated with PTBs. In this study, we determined concentrations of 21 elements in cord whole blood and explored the associations between element concentrations and PTB in a nested case-control study within a birth cohort in Guangdong, China. Finally, 515 preterm infants and 595 full-term infants were included. We performed single-element and multi-element logistic regressions to evaluate linear relationships between element concentrations and PTB. According to the results of single-element models, most essential elements (including K, Ca, Si, Zn, Se, Sr and Fe) were negatively associated with PTB, while Cu, V, Co and Sn were positively associated with PTB. Of the non-essential elements, Sb, Tl, and U were positively associated with PTB, while Pb was negatively associated with PTB. The multi-element model results for most elements were similar, except that the association between Mg and PTB was shown to be significantly positive, and the association for Cu became much larger. A possible explanation is that the effects of Mg and Cu may be influenced by other elements. We performed restricted cubic spline (RCS) regressions and found significantly non-linear exposure-response relationships for Mg, Se, Sr, K and Sb, indicating that the effects of these elements on PTB are not simply detrimental or beneficial. We also examined the joint effect using a Bayesian kernel machine regression (BKMR) model and found the risk of PTB decreased significantly with element mixture concentration when lnC was larger than the median. Bivariate interaction analysis suggested antagonistic effects of Sb on Zn and Sr, which may be attributed to Sb negating the antioxidant capacity of Zn and Sr. This study provides additional evidence for the effect of element exposures on PTB, and will have implications for the prevention of excessive exposures or inappropriate element supplementation during pregnancy.

miR-2115-3p inhibits ferroptosis by downregulating the expression of glutamic-oxaloacetic transaminase in preeclampsia

INTRODUCTION

Recently, ferroptosis has been reported to be closely related to preeclampsia (PE). However, the mechanisms associated with ferroptosis in PE have been poorly studied.

METHODS

A PE rat model was established via reduced uterine perfusion pressure (RUPP) surgery. A Ferroptosis inhibitor was used to treat the model rats. Blood pressure, urine protein, sFlt-1, GSH, GSH-PX, MDA, total Fe, Fe (II), and Fe (Ⅲ) levels were detected. Placenta morphological changes and fetal survival rate were observed and counted, respectively. miRNA sequencing and bioinformatical analysis were conducted to establish the ferroptosis-related interaction network of miRNAs-mRNAs in PE. After hypoxia treatment, cells were silenced glutamic-oxaloacetic transaminase1 (GOT1) or overexpressed miR-2115-3p/GOT1. Cellular proliferation, invasion, and reactive oxygen species (ROS) were determined. The ferroptosis-related factors levels (ACSL4, TfR1, GPX4, SCL7A11, GSH, GSH-PX, Fe (II), and MDA) were quantified.

RESULTS

In vivo, ferrostatin-1 attenuated ferroptosis in the PE models, significantly increasing fetal survivability. The miR-2115-3p/GOT1 pathway was screened for possible association with abnormal ferroptosis in PE. miR-2115-3p was discovered to interact with the mRNA of GOT1. Inhibition of GOT1 and overexpression of miR-2115-3p reversed the decrease in cell proliferation capacity, GSH, GSH-PX, and GPX4 levels, and the increase in ROS, ACSL4, TfR1, MDA, total Fe, and Fe (II) levels induced by hypoxia. However, simultaneous overexpression of miR-2115-3p and GOT1 reversed the above results of overexpression of miR-2115-3p.

DISCUSSION

miR-2115-3p might interact with the GOT1 mRNA to downregulate its expression, further inhibiting the hypoxia-promoted ferroptosis in a PE model.

Analysis of essential, toxic, rare earth, and noble elements in maternal and umbilical cord blood

Progressive industrialization in recent decades has contributed to the increase of metal levels in the environment, which has a dangerous impact on human health, primarily pregnant women. In this study, we aimed to compare levels of various elements in maternal and umbilical cord (UC) plasma samples collected from 125 healthy pregnant women, conduct correlation analysis among paired plasma samples, and compare our data with other populations worldwide. The study design included the following elements: essential (Mn, Co, Cu, Zn, Se, Mo), non-essential (Be, Al, Ni, As, Rb, Sr, Cd, Sb, Pb, U), rare earth (La, Pr, Ce, Nd, Sm, Eu, Gd, Dy, Ho, Er), and noble metals (Ru, Rh, Re, Pt). Levels of 30 elements were higher in maternal plasma than in UC plasma samples. However, no disparities at the statistically significant level were found for Be, Zn, Rb, Cd, Ce, and Ho. Correlation analysis among paired plasma samples revealed only positive/synergistic correlations of different strengths between most elements. Compared to other countries across the globe, our participants had considerably lower plasma levels of Zn and higher levels of Co, Ni, and As. This study provides not only a new and deeper comprehension, but also the first insight into the levels, correlation, distribution, and potential transplacental transfer of 30 elements.

Nutritional properties of selected superfood extracts and their potential health benefits

Background

The term 'superfoods' is used to market foods considered to have significant health benefits. 'Superfoods' are claimed to prevent diseases as well as improving overall health, though the lack of explicit criteria means that any food can be labelled 'super' without support from scientific research. Typically, these 'superfoods' are rich in a particular nutrient for example antioxidants or omega-3 fatty acids. The objective of this study was to investigate the nutritional properties of a selection of superfood seeds: flax, chia, hulled sunflower and two types of processed hemp seeds and determine whether they may have potential health benefits.

Methods

We developed a simple aqueous extraction method for ground seeds and analysed their composition by mineral, protein and monosaccharide analyses. Cell viability assays were performed on Caco-2 and IEC-6 intestinal epithelial cells using increasing doses of the prepared extracts.

Results

Increased cell viability was observed in both cell lines with increasing concentrations of the flax seed, chia seed or hulled sunflower extracts (P < 0.05). Compositional analyses revealed the presence of polysaccharides, proteins and essential minerals in the aqueous extracts and in vitro assays showed sunflower had the highest antioxidant activity. However, differences in extract composition and antioxidant properties could not be directly related to the observed increase in cell viability suggesting that other components in the extracts may be responsible. Future studies will further characterize these extracts and investigate whether they are beneficial for gastrointestinal health.

Circulating trace elements for the prediction of preeclampsia and small for gestational age babies

INTRODUCTION

Poor gestational outcomes due to placental insufficiency can have lifelong consequences for mother and child.

OBJECTIVE

There is a need for better methods of diagnosis, and elemental metabolomics may provide a means to determine the risk of gestational disorders.

METHODS

This study used blood plasma samples collected at 36 weeks' gestation from women who later developed preeclampsia (n = 38), or small-for-gestational age babies (n = 91), along with matched controls (n = 193). Multi-element analysis was conducted by inductively coupled plasma mass spectrometer (ICP-MS), allowing simultaneous measurement of 28 elements.

RESULTS

Women who later developed PE, exhibited significantly increased concentrations of K, Rb and Ba. For SGA pregnancies, there was a significant increase in Cu and a decrease in As concentrations. Despite significant differences in single elements, the elemental profile of groups indicated no clustering of control, PE, or SGA samples. Positive predicative values correctly identified approximately 60% of SGA and 70% of PE samples.

CONCLUSION

This is the first-time elemental metabolomics has been used to predict SGA and PE at 36 weeks. Though significant changes were identified, routine clinical use may be limited but may contribute to a multi marker test. Future analysis should include other biomarkers, metabolic data or clinical measurements made throughout gestation.

24 h urinary creatinine excretion during pregnancy and its application in appropriate estimation of 24 h urinary iodine excretion

BACKGROUND

Urinary creatinine can be used to adjust urinary iodine to evaluate iodine nutritional status during pregnancy. However, the reference intervals and impact factors of urinary creatinine are unknown.

METHODS

24 h urine creatinine concentration (24 hUCr) and spot UCr at four different time periods of the day of pregnant women from Part 1 (n = 743) were measured. Linear regression analysis was performed to identify the impact factors of 24 h urinary creatinine excretion (24 hUCrE) and obtain the estimated 24 h urinary creatinine excretion (24 hUCrE_est). Then measured urinary iodine concentration (UIC) of 24 h and at fasting of pregnant women from Part 2 (n = 325), used spot urinary iodine to creatinine concentration ratio (UIC/UCr) and 24 hUCrE_est to calculate the estimated 24 h urinary iodine excretion (24 hUIE_est), finally checked the consistency and correlation of 24 hUIE_est and 24 h urinary iodine excretion (24 hUIE).

RESULTS

In Part 1, the median 24 hUCrE was 1.24(IQR0.98-1.76)g, and the reference interval was 0.61-2.93 g. The median 24 hUCr was 0.76 (IQR0.57-1.01)g/L, and the reference interval was 0.36-1.88 g/L. Multiple linear regression results showed that pregnancy weight was an influencing factor to 24 hUCrE after adjusting by gestational weeks, age, pre-pregnancy BMI, and percentage of body fat (F = 45.029, p＜0.001). In Part 2, there was no statistically significant difference between 24 hUIE_est and 24 hUIE (Z =-0.767, p = 0.443). Using 24hUIE as the gold standard, the relative average difference in 24hUIE_est was 4.2 %, the relative average differences for UIC and UIC/UCr were 32.4 % and 37.2 %. The reference interval of 24 hUIE and 24 hUIE_est were 88.43-585.90 μg and 50.97-700.39 μg, respectively.

CONCLUSIONS

The reference intervals of 24 hUCrE, spot UCr, 24 hUIE, and 24 hUIE_est during pregnancy were established. 24 hUCrE has important application value in iodine nutrition evaluation to gain more lead time for pregnant women with iodine nutrition-related diseases.

Elemental Metabolomics for Prediction of Term Gestational Outcomes Utilising 18-Week Maternal Plasma and Urine Samples

A normal pregnancy is essential to establishing a healthy start to life. Complications during have been associated with adverse perinatal outcomes and lifelong health problems. The ability to identify risk factors associated with pregnancy complications early in gestation is vitally important for preventing negative foetal outcomes. Maternal nutrition has been long considered vital to a healthy pregnancy, with micronutrients and trace elements heavily implicated in maternofoetal metabolism. This study proposed the use of elemental metabolomics to study multiple elements at 18 weeks gestation from blood plasma and urine to construct models that could predict outcomes such as small for gestational age (SGA) (n = 10), low placental weight (n = 18), and preterm birth (n = 13) from control samples (n = 87). Samples collected from the Lyell McEwin Hospital in Adelaide, South Australia, were measured for 27 plasma elements and 37 urine elements by inductively coupled plasma mass spectrometry. Exploratory analysis indicated an average selenium concentration 20 μg/L lower than established reference ranges across all groups, low zinc in preterm (0.64 μg/L, reference range 0.66-1.10 μg/L), and higher iodine in preterm and SGA gestations (preterm 102 μg/L, SGA 111 μg/L, reference range 40-92 μg/L). Using random forest algorithms with receiver operating characteristic curves, low placental weight was predicted with 86.7% accuracy using plasma, 78.6% prediction for SGA with urine, and 73.5% determination of preterm pregnancies. This study indicates that elemental metabolomic modelling could provide a means of early detection of at-risk pregnancies allowing for more targeted monitoring of mothers, with potential for early intervention strategies to be developed.