Ecological change of the gut microbiota during pregnancy and progression to dyslipidemia

The composition of the gut microbiome was previously found to be associated with clinical responses to dyslipidemia, but there is limited consensus on the dynamic change of the gut microbiota during pregnancy and the specific microbiome characteristics linked to dyslipidemia in pregnant women. We collected fecal samples from 513 pregnant women at multiple time points during pregnancy in a prospective cohort. Taxonomic composition and functional annotations were determined by 16S rRNA amplicon sequencing and shotgun metagenomic sequencing. The predictive potential of gut microbiota on the risk of dyslipidemia was determined. The gut microbiome underwent dynamic changes during pregnancy, with significantly lower alpha diversity observed in dyslipidemic patients compared to their healthy counterparts. Several genera, including Bacteroides, Paraprevotella, Alistipes, Christensenellaceae R7 group, Clostridia UCG-014, and UCG-002 were negatively associated with lipid profiles and dyslipidemia. Further metagenomic analysis recognized a common set of pathways involved in gastrointestinal inflammation, where disease-specific microbes played an important role. Machine learning analysis confirmed the link between the microbiome and its progression to dyslipidemia, with a micro-averaged AUC of 0.824 (95% CI: 0.782-0.855) combined with blood biochemical data. Overall, the human gut microbiome, including Alistipes and Bacteroides, was associated with the lipid profile and maternal dyslipidemia during pregnancy by perturbing inflammatory functional pathways. Gut microbiota combined with blood biochemical data at the mid-pregnancy stage could predict the risk of dyslipidemia in late pregnancy. Therefore, the gut microbiota may represent a potential noninvasive diagnostic and therapeutic strategy for preventing dyslipidemia in pregnancy.

The effect of ambient ozone exposure on three types of diabetes: a meta-analysis

BACKGROUND

Ozone as an air pollutant is gradually becoming a threat to people's health. However, the effect of ozone exposure on risk of developing diabetes, a fast-growing global metabolic disease, remains controversial.

OBJECTIVE

To evaluate the impact of ambient ozone exposure on the incidence rate of type 1, type 2 and gestational diabetes mellitus.

METHOD

We systematically searched PubMed, Web of Science, and Cochrane Library databases before July 9, 2022, to determine relevant literature. Data were extracted after quality evaluation according to the Newcastle Ottawa Scale (NOS) and the agency for healthcare research and quality (AHRQ) standards, and a meta-analysis was used to evaluate the correlation between ozone exposure and type 1 diabetes mellitus (T1D), type 2 diabetes mellitus (T2D), and gestational diabetes mellitus (GDM). The heterogeneity test, sensitivity analysis, and publication bias were performed using Stata 16.0.

RESULTS

Our search identified 667 studies from three databases, 19 of which were included in our analysis after removing duplicate and ineligible studies. Among the remaining studies, three were on T1D, five were on T2D, and eleven were on GDM. The result showed that ozone exposure was positively correlated with T2D [effect size (ES) = 1.06, 95% CI: 1.02, 1.11] and GDM [pooled odds ratio (OR) = 1.01, 95% CI: 1.00, 1.03]. Subgroup analysis demonstrated that ozone exposure in the first trimester of pregnancy might raise the risk of GDM. However, no significant association was observed between ozone exposure and T1D.

CONCLUSION

Long-term exposure to ozone may increase the risk of T2D, and daily ozone exposure during pregnancy was a hazard factor for developing GDM. Decreasing ambient ozone pollution may reduce the burden of both diseases.

Prenatal exposure to pesticides and domain-specific neurodevelopment at age 12 and 18 months in Nanjing, China

BACKGROUND

The extensive usage of pesticides has led to a ubiquitous exposure in the Chinese general population. Previous studies have demonstrated developmental neurotoxicity associated with prenatal exposure to pesticides.

OBJECTIVES

We aimed to delineate the landscape of internal pesticides exposure levels from pregnant women's blood serum samples, and to identify the specific pesticides associated with the domain-specific neuropsychological development.

METHODS

Participants included 710 mother-child pairs in a prospective cohort study initiated and maintained in Nanjing Maternity and Child Health Care Hospital. Maternal spot blood samples were collected at enrollment. Leveraging on an accurate, sensitive and reproducible analysis method for 88 pesticides, a total of 49 pesticides were measured simultaneously using gas chromatography-triple quadrupole tandem mass spectrometry (GC-MS/MS). After implementing a strict quality control (QC) management, 29 pesticides were reported. We assessed neuropsychological development in 12-month-old (n = 172) and 18-month-old (n = 138) children using the Ages and Stages Questionnaire (ASQ), Third Edition. Negative binomial regression models were used to investigate the associations between prenatal exposure to pesticides and ASQ domain-specific scores at age 12 and 18 months. Restricted cubic spline (RCS) analysis and generalized additive models (GAMs) were fitted to evaluate non-linear patterns. Longitudinal models with generalized estimating equations (GEE) were conducted to account for correlations among repeated observations. Weighted quantile sum (WQS) regression and Bayesian kernel machine regression (BKMR) were applied to examining the joint effect of the mixture of pesticides. Several sensitivity analyses were performed to assess the robustness of the results.

RESULTS

We observed that prenatal exposure to chlorpyrifos was significantly associated with a 4 % decrease in the ASQ communication scores both at age 12 months (RR, 0.96; 95 % CI, 0.94-0.98; P < 0.001) and 18 months (RR, 0.96; 95 % CI, 0.93-0.99; P < 0.01). In the ASQ gross motor domain, higher concentrations of mirex (RR, 0.96; 95 % CI, 0.94-0.99, P < 0.01 for 12-month-old children; RR, 0.98; 95 % CI, 0.97-1.00, P = 0.01 for 18-month-old children), and atrazine (RR, 0.97; 95 % CI, 0.95-0.99, P < 0.01 for 12-month-old children; RR, 0.99; 95 % CI, 0.97-1.00, P = 0.03 for 18-month-old children) were associated with decreased scores. In the ASQ fine motor domain, higher concentrations of mirex (RR, 0.98; 95 % CI, 0.96-1.00, P = 0.04 for 12-month-old children; RR, 0.98; 95 % CI, 0.96-0.99, P < 0.01 for 18-month-old children), atrazine (RR, 0.97; 95 % CI, 0.95-0.99, P < 0.001 for 12-month-old children; RR, 0.98; 95 % CI, 0.97-1.00, P = 0.01 for 18-month-old children), and dimethipin (RR, 0.94; 95 % CI, 0.89-1.00, P = 0.04 for 12-month-old children; RR, 0.93; 95 % CI, 0.88-0.98, P < 0.01 for 18-month-old children) were associated with decreased scores. The associations were not modified by child sex. There was no evidence of statistically significant nonlinear relationships between pesticides exposure and RRs of delayed neurodevelopment (P_nonlinearity > 0.05). Longitudinal analyses implicated the consistent findings.

CONCLUSION

This study gave an integrated picture of pesticides exposure in Chinese pregnant women. We found significant inverse associations between prenatal exposure to chlorpyrifos, mirex, atrazine, dimethipin and the domain-specific neuropsychological development (i.e., communication, gross motor and fine motor) of children at 12 and 18 months of age. These findings identified specific pesticides with high risk of neurotoxicity, and highlighted the need for priority regulation of them.

Maternal exposure to pesticides and autism or attention-deficit/hyperactivity disorders in offspring: A meta-analysis

OBJECTIVE

To analyze the association between maternal pesticide exposure and autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorders (ADHD) in offspring.

METHOD

Five databases including PubMed, Embase, Web of Science, Medline, as well as PsycINFO were systematically retrieved for the records related to pesticide exposure during pregnancy and ASD and ADHD in offspring before August 30, 2022. The pesticide category, maternal age and window of exposure as the main subgroups were presented.

RESULTS

949 studies were initially identified, and 19 studies were eventually included. Eleven were on ASD, seven were on ADHD, and one was on both disorders. Maternal pesticide exposure was positively related to ASD (pooled OR = 1.19 (95%CI: 1.04 to 1.36)) and ADHD (pooled OR = 1.20 (95%CI: 1.04 to 1.38)) in offspring. In the subgroup analysis, organophosphorus pesticides (OPs) (pooled OR = 1.14 (95%CI: 1.04 to 1.24)), pyrethroid (pooled OR = 1.40 (95%CI: 1.09 to 1.80)), and maternal age ≥30 years old (pooled OR = 1.24 (95%CI: 1.10 to 1.40)) increased the risk of ASD in offspring. Maternal organochlorine pesticides (OCPs) exposure was a risk factor for ADHD in offspring (pooled OR = 1.22 (95%CI: 1.03 to 1.45)).

CONCLUSION

Maternal pesticide exposure increased the risk of ASD and ADHD in offspring. Moreover, OPs, pyrethroid, and maternal age ≥30 years old were found to be risk factors affecting children's ASD. Maternal exposure to OCPs increased the risk of ADHD in offspring. Our findings contribute to our understanding of health risks related to maternal pesticide exposure and indicate that the in utero developmental period is a vulnerable window-of-susceptibility for ASD and ADHD risk in offspring. These findings should guide policies that limit maternal exposure to pesticides, especially for pregnant women living in agricultural areas.

The landscape of micron-scale particles including microplastics in human enclosed body fluids

Exogenous microparticles including microplastics are novel pollutants that could persist in the environment with potential health effects, while crucial data on their exposure in humans are still lacking. To understand the panorama of microparticles including microplastics exposure and distribution characteristics in different kinds of body fluids. A non-targeted microparticle internal exposure landscape analysis was done in thirteen kinds of human enclosed body fluids covering eight body systems. Totally 104 patients aged 24-96 years with an average age of 56 years were included in this study. After sample digestion, non-soluble microparticles were detected and identified with one Raman Microspectroscope under a strict quality control-particle detection system. Totally 702 microparticles with size ranging from 2.15 to 103.27 µm were detected in samples. Microparticles were identified into 84 substances or 66 molecules, most of which were firstly reported inside human body. Nine kinds of microplastics were originally reported in human body fluids with their size ranging from 19.66 to 103.27 µm. Microparticles exposure was unexpectedly high inside the human body despite the protection of biological barriers and membranes, raising awareness of the impact of particle pollution on sustainable development.

Geographical variation in the effect of ambient temperature on infectious diarrhea among children under 5 years

Understanding the geographical distribution in the association of temperature with childhood diarrhea can assist in formulating effective localized diarrhea prevention practices. This study aimed to identify the geographical variation in terms of temperature thresholds, lag effects, and attributable fraction (AF) in the effects of ambient temperature on Class C Other Infectious Diarrhea (OID) among children <5 years in Jiangsu Province, China. Daily data of OID cases and meteorological variables from 2015 to 2019 were collected. City-specific minimum morbidity temperature (MMT), increasing risk temperature (IRT), maximum risk temperature (MRT), maximum risk lag day (MRD), and lag day duration (LDD) were identified as risk indicators for the temperature-OID relationship using distributed lag non-linear models. The AF of OID incidence due to temperature was evaluated. Multivariable regression was also applied to explore the underlying modifiers of the AF. The geographical distributions of MMT, IRT, and MRT generally decreased with the latitude increment varying between 22.3-34.7 °C, -2.9-18.1 °C, and -6.8-23.2 °C. Considerable variation was shown in the AF ranging from 0.2 to 8.5%, and the AF significantly increased with latitude (95% confidence interval (CI): -3.458, -0.987) and economic status decrement (95% CI: -0.161, -0.019). Our study demonstrated between-city variations in the association of temperature with OID, which should be considered in the localized clinical and public health practices to decrease the incidence of childhood diarrhea.

Pyridoxal 5'-phosphate alleviates prenatal pyridaben exposure-induced anxiety-like behaviors in offspring

Pyridaben (PY) is a widely used organochlorine acaricide, which can be detected in the peripheral blood of pregnant women. Available evidence suggests that PY has reproductive toxicity. However, it remains uncertain whether prenatal PY exposure impacts neurobehavioral development in offspring. Here, we administered PY to pregnant mice at a dose of 0.5 and 5 mg kg^-1 day^-1 via gavage and observed anxiety-like behaviors in PY offspring aged five weeks. We then integrated the metabolome and transcriptome of the offspring's brain to explore the underlying mechanism. Metabolome data indicated that the vitamin B6 metabolism pathway was significantly affected, and the pyridoxal 5'-phosphate (PLP) concentration and the active form of vitamin B6 was significantly reduced. Moreover, the transcriptome data showed that both PLP generation-related Pdxk and anxiety-related Gad1 were significantly down-regulated. Meanwhile, there was a decreasing trend in the concentration of GABA in the hippocampal DG region. Next, we supplemented PLP at a dose of 20 mg kg^-1 day^-1 to the PY offspring via intraperitoneal injection at three weeks. We found up-regulated expression of Pdxk and Gad1 and restored anxiety-like behaviors. This study suggests that prenatal exposure to PY can disrupt vitamin B6 metabolism, reduce the concentration of PLP, down-regulate the expression levels of Pdxk and Gad1, inhibit the production of GABA, and ultimately lead to anxiety-like behaviors in offspring.

Prenatal titanium exposure and child neurodevelopment at 1 year of age: A longitudinal prospective birth cohort study

Previous animal studies provided the evidence that prenatal titanium exposure can cause neurotoxicity in their offspring, while human data is vacant. Our aim was to identify the associations of prenatal titanium exposure with the child neurodevelopment. Participants in present study were recruited during early pregnancy between 2014 and 2017. Urinary concentrations of titanium at first trimester were determined. We assessed child neurodevelopment using the Chinese version of Gesell Developmental Schedules at first year follow-up. The multivariable linear regressions and the robust modified Poisson regressions were used to estimate the associations of specific gravity corrected urinary titanium concentrations with the child neurodevelopment. In adjusted models, children's developmental quotient scores in the language domain were 2.03 points (95% CI: -3.66, -0.40) lower in the highest tertile of prenatal urinary titanium than in the lowest tertile. Also, children with prenatal urinary titanium in the highest tertile had 1.42 times (95% CI: 1.17, 1.72) increased risk of language development delay compared to those in the lowest tertile. No statistically significant associations were observed between titanium exposure and child development delay in motor, adaptive and social areas. The findings indicated that prenatal higher titanium exposure was associated with impaired language development, suggesting that titanium might act as developmental neurotoxicants.

Chemical mixture exposure patterns and obesity among U.S. adults in NHANES 2005-2012

BACKGROUND

The effect of chemical exposure on obesity has raised great concerns. Real-world chemical exposure always imposes mixture impacts, however their exposure patterns and the corresponding associations with obesity have not been fully evaluated.

OBJECTIVES

To discover obesity-related mixed chemical exposure patterns in the general U.S.

METHODS

Sparse Decompositional Regression (SDR), a model adapted from sparse representation learning technique, was developed to identify exposure patterns of chemical mixtures with exclusion (non-targeted model) and inclusion (targeted model) of health outcomes. We assessed the relationships between the identified chemical mixture patterns and obesity-related indexes. We also conducted a comprehensive evaluation of this SDR model by comparing to the existing models, including generalized linear regression model (GLM), principal component analysis (PCA), and Bayesian kernel machine regression (BKMR).

RESULTS

Eight core exposure patterns were identified using the non-targeted SDR model. Patterns of high levels of MEP, high levels of naphthalene metabolites (ΣOH-Nap), and a pattern of high exposure levels of MCOP, MCNP, and MCPP were positively associated with obesity. Patterns of high levels of BP3, and a pattern of higher mixed levels of MPB, PPB, and MEP were found to have negative associations. Associations were strengthened using the targeted SDR model. In the single chemical analysis by GLM, BP3, MBP, PPB, MCOP, and MCNP showed significant associations with obesity or body indexes. The SDR model exceeded the performance of PCA in pattern identification. Both SDR and BKMR identified a positive contribution of ΣOH-Nap and MCOP, as well as a negative contribution of BP3 and PPB to obesity.

CONCLUSION

Our study identified five core exposure patterns of chemical mixtures significantly associated with obesity using the newly developed SDR model. The SDR model could open a new avenue for assessing health effects of environmental mixture contaminants.

Pigment microparticles and microplastics found in human thrombi based on Raman spectral evidence

INTRODUCTION

Environmental microparticle is becoming a global pollutant and the entire population is increasingly exposed to the microparticles from artificial materials. The accumulation of microparticles including microplastics and its subsequent effects need to be investigated timely to keep sustainable development of human society.

OBJECTIVES

This study aimed to explore the accumulation of environmental particles in thrombus, the pathological structure in the blood circulation system.

METHODS

Patients receiving cardiovascular surgical operations were screened and twenty-six thrombi were collected, digested and filtered. Non-soluble microparticles were enriched on the filter membrane and then were analyzed and identified with Raman Spectrometer. The associations of particle status (presence or absence) or particle number in the thrombus and clinical indicators were examined. One strict quality control-particle detection system was designed to eliminate environmental contaminations.

RESULTS

Among twenty-six thrombi, sixteen contained eighty-seven identified particles ranging from 2.1 to 26.0 μm in size. The number of microparticles in each thrombus ranged from one to fifteen with the median reaching five. All the particles found in thrombi were irregularly block-shaped. Totally, twenty-one phthalocyanine particles, one Hostasol-Green particle, and one low-density polyethylene microplastic, which were from synthetic materials, were identified in thrombi. The rest microparticles included iron compounds and metallic oxides. After the adjustment for potential confounders, a significantly positive association between microparticle number and blood platelet levels was detected (P < 0.01).

CONCLUSION

This study provides the first photograph and Raman spectrum evidence of microparticles in thrombi. A large number of non-soluble particles including synthetic material microparticles could accumulate in arteries, suggesting that the risk of microparticle exposure was under-estimated and the re-evaluation of its health effects is urgently needed. There will be a series of reports on assessing the health effects of microparticle exposure in humans in the future and this research provided clues for the subsequent research.

Estimating the effects of policies on infertility prevalence worldwide

Background

Infertility has troubled millions of people worldwide while always being an ignored issue. The high cost of treatment or lack of services placed a barrier to the alleviation of infertility status. Governments play a significant role to promote infertility-related policies for better access to infertility services and comprehensive supports for infertile people.

Methods

Data of infertility status indicators and infertility-related policies in ten representative countries were collected. An infertility-related policy system was established, then classification and quantification were processed according to specific criteria, and different policy implementation patterns were identified. The effectiveness of specific infertility-related policy and various patterns on infertility prevalence relief between 1990 and 2017 were evaluated via generalized linear models and analyses of covariance for the first time.

Results

Economic support policies would be less prioritized compared with social security policies, while economic support policy had a significant positive role in the decline of female infertility prevalence (β = -2·16, p = 0·042). In detail, insurance coverage and economic reward policies were crucial (β = -3·31, p = 0·031; β = -4·10, p = 0·025) with adjusted with covariates. The effect of economic support-oriented pattern was relatively better than other patterns for both male and female infertility prevalence relief. Nevertheless, the effectiveness of gradual-promotion pattern seemed preferable for male infertility prevalence relief while was similar with simultaneous-promotion pattern for females.

Conclusions

Our data-driven analysis revealed that insurance coverage and economic reward policies played the pivotal role in moderation of female infertility status. Economic support-oriented pattern and gradual-promotion pattern were preferable when promoting infertility-related policies.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-022-13802-9.

Associations between PM2.5 exposure and infant growth: A mediation analysis of oral microbiota

BACKGROUND

Previous studies have linked growth retardation with ambient fine particulate matter (PM_2.5) exposure. However, few studies explored such association from the perspective of microbiota, such as oral microbiota. We aimed to identify the potential role of oral microbiota in the links between PM_2.5 exposure and infant growth.

METHODS

Baseline information of 335 recruited mother-child pairs was collected by structured questionnaires. Growth indicators (weight, length) of one-year-old infants were abstracted from medical records when they had physical examination and corresponding z scores were calculated. 16S rRNA gene amplicon sequencing was performed to assess oral microbiota of infants and co-abundance groups (CAGs) were further calculated. We assessed PM_2.5 levels by inverse distance weighting (IDW). Generalized linear regression and mediation analysis were performed to determine associations between PM_2.5 exposure, oral microbiota and growth indicators.

RESULTS

Per 10 μg m^-3 increment of PM_2.5 in the period of 10th month-examination was associated with decreased length z score (β = -1.97, 95%CI: -3.83, -0.11). Oral microbiota correlated with weight z score and body mass index (BMI) z score was identified by Spearman correlation analysis. CAG4 was statistically associated with increased weight z score (β = 3.40, 95%CI: 0.29, 6.51) and BMI z score (β = 5.44, 95%CI: 1.00, 9.87). Several bacteria in the level of genus and CAG associated with PM_2.5 exposure were additionally identified (P < 0.05). Mediation analysis revealed that PM_2.5 in the period of birth-3rd month impacted the z scores of weight and BMI by altering relative abundance of Megasphaera (P < 0.05).

CONCLUSION

PM_2.5 exposure from 10th to 12th month after birth could retard infant linear growth. PM_2.5 might impact oral microbiota of one-year-old infants. Growth-related bacteria and CAGs were identified. Megasphaera might function as mediator between PM_2.5 exposure during birth-3rd month and infant z scores of weight and BMI.

Exposure to multiple trace elements and miscarriage during early pregnancy: A mixtures approach

BACKGROUND

Exposure to some conventional trace elements has been found to be associated with miscarriage; however, evidence for combined exposure is inconclusive. Therefore, it is important to explore the joint associations between toxic and essential trace elements and miscarriage.

METHODS

This cross-sectional study measured a wide range of element levels in the whole blood of pregnant women by using inductively coupled plasma mass spectrometry. The associations between individual elements and miscarriage were appraised using logistic regression model. Multi-exposure models, including Bayesian kernel machine regression (BKMR) and weighted quantile sum regression (WQS), were used to explore the mixed exposure to elements. Furthermore, grouped weighted quantile sum (GWQS) considered multiple elements with different magnitudes and directions of associations.

RESULTS

In logistic regression, the odds ratios (ORs) with a 95% confidence interval (CI) in the highest quartiles were 5.45 (2.00, 15.91) for barium, 0.28 (0.09, 0.76) for copper, and 0.32 (0.12, 0.83) for rubidium. These exposure-outcome associations were confirmed and supplemented by BKMR, which indicated a positive association for barium and negative associations for copper and rubidium. In WQS, a positive association was found between mixed elements and miscarriage (OR: 1.71; 95% CI: 1.07, 2.78), in which barium (75.7%) was the highest weighted element. The results of GWQS showed that the toxic trace element group dominated by barium was significantly associated with increased ORs (OR: 2.71; 95% CI: 1.74, 4.38). Additionally, a negative association was observed between the essential trace element group and miscarriage (OR: 0.32; 95% CI: 0.18, 0.54), with rubidium contributing the most to the result.

CONCLUSIONS

As a toxic trace element, barium was positively associated with miscarriage both by individual and multiple evaluations, while essential trace elements, particularly rubidium and copper, exhibited negative associations. Our findings provide significant evidence for exploring the effects of trace elements on miscarriage.

Assessing maternal thyroid function and its relationship to duration of the first stage of labor

INTRODUCTION

Maternal thyroid function plays a critical role in the normal labor process. Whether maternal thyroid function affects the duration of the first stage of labor is still unknown.

METHODS

Maternal serum levels of free thyroxine (FT4), thyroid-stimulating hormone (TSH) and thyroid peroxidase antibody (TPOAb) were detected in 31,382 pregnant women. A multiple linear regression model was applied to investigate the effect of maternal thyroid function on the duration of the first stage of labor.

RESULTS

FT4 level in the second trimester and in the third trimester was found to be negatively associated with duration of the first stage of labor (β = -1.30 h, 95% CI: -2.28, -0.32, P < 0.01; β = -0.35 h, 95% CI: -0.61, -0.10, P < 0.01). TSH level in the third trimester was found to be positively associated with the duration of the first stage of labor (β = 0.12 h, 95% CI: 0.06, 0.18, P < 0.001). Per unit increase in TPOAb (IU/mL) in the second trimester and in the third trimester was significantly associated with prolonged first stage of labor (β = 0.08 h, 95% CI: 0.01, 0.14, P = 0.02; β = 0.09 h, 95% CI: 0.02, 0.15, P = 0.01). For pregnant women suffering from subclinical hypothyroidism combined without TPOAb, TSH level in the third trimester exhibited a significant positive association with the length of the first stage of labor (β = 2.44 h, 95% CI: 0.03, 4.84, P = 0.04).

CONCLUSIONS

These findings suggest that maternal FT4, TSH and TPOAb might be important predictors of the first stage of labor.

Associations between the Maternal Exposome and Metabolome during Pregnancy

BACKGROUND

Maternal exposure to environmental chemicals during pregnancy can influence various maternal and offspring health parameters. Modification of maternal metabolism by environmental exposure may be an important pathway for these impacts. However, there is limited evidence regarding exposure to a wide array of chemicals and the metabolome during pregnancy.

OBJECTIVES

We investigated the relationship between the urinary exposome and metabolome during pregnancy.

METHODS

Urine samples were collected in the first and third trimesters from 1,024 pregnant women recruited in prenatal clinics in Jiangsu Province, China. The exposome was analyzed using the first trimester sample with ultra-high performance liquid chromatography-high resolution accurate mass spectrometry (UHPLC-HRMS) and inductively coupled plasma mass spectrometry. The metabolome was analyzed using the third trimester sample with UHPLC-HRMS. We evaluated associations between each of 106 exposures in the first trimester with 139 metabolites in the third trimester.

RESULTS

We identified 1,245 significant associations (p<3.39×10-6, Bonferroni correction) between chemical exposures and maternal metabolism during pregnancy. Among elements, the largest number of the significant metabolic associations were observed for magnesium, and among organic compounds, for 4-tert-octylphenol. We used exposome-metabolome associations to explore mechanisms underlying published associations between prenatal chemical exposures and offspring health outcomes. This integration of the literature with our results suggests that reported associations between 10 analytes and birth weight, gestational age, fat deposition, neurobehavioral development, immunological disorders, and hypertension may be partially mediated by metabolites associated with these exposures.

DISCUSSION

This high-dimensional analysis of the urinary exposome and metabolome identified many associations between chemical exposures and maternal metabolism during pregnancy. Integration of these associations with the literature on health outcomes of exposure suggests that environmental modulation of the maternal metabolome may play a role in the association between prenatal exposure on pregnancy and child health outcomes. https://doi.org/10.1289/EHP9745.

Association of Maternal Dietary Patterns during Gestation and Offspring Neurodevelopment

The health effects of diet are long term and persistent. Few cohort studies have investigated the influence of maternal dietary patterns during different gestational periods on offspring's health outcomes. This study investigated the associations between maternal dietary patterns in the mid- and late-gestation and infant's neurodevelopment at 1 year of age in the Jiangsu Birth Cohort (JBC) Study. A total of 1178 mother-child pairs were available for analysis. A semiquantitative food frequency questionnaire (FFQ) was used to investigate dietary intake at 22-26 and 30-34 gestational weeks (GWs). Neurodevelopment of children aged 1 year old was assessed using Bayley-Ⅲ Screening Test. Principal component analysis (PCA) and Poisson regression were used to extract dietary patterns and to investigate the association between dietary patterns and infant neurodevelopment. After adjusting for potential confounders, the maternal 'Aquatic products, Fresh vegetables and Homonemeae' pattern in the second trimester was associated with a lower risk of being non-competent in cognitive and gross motor development, respectively (cognition: aRR = 0.84; 95% CI 0.74-0.94; gross motor: aRR = 0.80; 95% CI 0.71-0.91), and the similar pattern, 'Aquatic products and Homonemeae', in the third trimester also showed significant association with decreased risk of failing age-appreciate cognitive and receptive communication development (cognition: aRR = 0.89; 95% CI 0.80-0.98; receptive communication: aRR = 0.91; 95% CI 0.84-0.99). Notably, adherence to the dietary pattern with relatively high aquatic and homonemeae products in both trimesters demonstrated remarkable protective effects on child neurodevelopment with the risk of being non-competent in cognitive and gross motor development decreasing by 59% (95% CI 0.21-0.79) and 63% (95% CI 0.18-0.77), respectively. Our findings suggested that adherence to the 'Aquatic products and Homonemeae' dietary pattern during pregnancy may have optimal effects on offspring's neurodevelopment.

Environmental chemical exposure dynamics and machine learning-based prediction of diabetes mellitus

BACKGROUND

With dramatically increasing prevalence, diabetes mellitus has imposed a tremendous toll on individual well-being. Humans are exposed to various environmental chemicals, which have been postulated as underappreciated but potentially modifiable diabetes risk factors.

OBJECTIVES

To determine the utility of environmental chemical exposure in predicting diabetes mellitus.

METHODS

A total of 8501 eligible participants from NHANES 2005-2016 were randomly assigned to a discovery (N = 5953) set and a validation (N = 2548) set. We applied random forest (RF) and least absolute shrinkage and selection operator (LASSO) regression with 10-fold cross-validation in the discovery set to select features, and built an optimal model to predict diabetes mellitus, blood insulin, fasting plasma glucose (FPG) and 2-h plasma glucose after oral glucose tolerance test (2-h PG after OGTT).

RESULTS

The machine learning model using LASSO regression predicted diabetes with an area under the receiver operating characteristics (AUROC) of 0.80 and 0.78 in the discovery set and validation set, respectively. The linear model predicted blood insulin level with an R² of 0.42 and 0.40 in the discovery set and validation set, respectively. For FPG, the discovery set and validation set yielded an R² of 0.16 and 0.15, respectively. For 2-h PG after OGTT, the discovery set and validation set yielded an R² of 0.18 and 0.17, respectively.

CONCLUSION

We used environmental chemical exposure, constructed machine learning models and achieved relatively accurate prediction for diabetes, emphasizing the predictive value of widespread environmental chemicals for complicated diseases.

Glufosinate-Ammonium Induced Aberrant Histone Modifications in Mouse Sperm Are Concordant With Transcriptome in Preimplantation Embryos

Glufosinate-ammonium (GLA) is a widely used herbicide with emerging concern over its male reproductive toxicity. Abnormalities in sperm histone modification induced by GLA exposure observed in our previous study aroused our interest in whether such alterations could further affect embryonic gene expression. Here we administered adult male mice with 0.2 mg/kg⋅day of GLA for 5 weeks to collect their sperm or 4-cell embryos after copulation. Cleavage Under Targets and Tagmentation (CUT&Tag) sequencing showed alterations of sperm H3 lysine 4 trimethylation (H3K4me3) and histone H3 lysine 27 acetylation (H3K27ac), which are active histone modification marks involved in embryo development, while RNA sequencing identified differentially expressed genes in 4-cell embryos. Differentially H3K4me3 and H3K27ac occupied regions were mainly distributed at the gene promoters and putative enhancers, and were enriched in pathways related to the immune system and nervous system. Integrative analysis of these sequencing data showed that genes such as Mgl2 with increased H3K4me3 and H3K27ac in sperm were up-regulated in embryos, and vice versa for genes such as Dcn. Additionally, differentially occupied H3K4me3 and H3K27ac in sperm were linked to gene expression changes in both paternal and maternal alleles of 4-cell embryos. In conclusion, GLA-induced changes in sperm H3K4me3 and H3K27ac are concordant with gene expression in preimplantation embryos, which might further affect embryo development and offspring health.

Association between ambient particulate matter exposure and semen quality in fertile men

BACKGROUND

Several studies have suggested adverse effects of particulate matter (PM) exposure on male reproductive health; few have investigated the association between PM exposure and semen quality in a large population of fertile men.

METHODS

We evaluated 14 parameters of semen quality in 1554 fertile men in Nanjing from 2014 to 2016. Individual exposure to particular matter ≤10 μm in diameter (PM₁₀) and ≤ 2.5 μm in diameter (PM_2.5) during key periods of sperm development (0-90, 0-9, 10-14, 15-69, and 70-90 days before semen collection) were estimated by inverse distance weighting interpolation. Associations between PM exposure and semen quality were estimated using multivariable linear regression.

RESULTS

Higher 90-days average PM_2.5 was in association with decreased sperm motility (2.21% for total motility, 1.93% for progressive motility per 10 μg/m³ increase, P <  0.001) and four quantitative aspects of sperm motion (curvilinear velocity (VCL), straight line velocity (VSL), average path velocity (VAP), and amplitude of lateral head displacement (ALH), P <  0.01). The association between PM_2.5 exposure and semen quality were generally stronger for the earlier exposure window (70-90 days prior to ejaculation) than for recent exposure (0-9, 10-14, or 15-69 days). In the subgroup of men who had normal sperm parameters (n = 1019), similar results were obtained. Ninety-days PM₁₀ exposure was associated only with decreased VCL and VAP and was not related to sperm concentration.

CONCLUSIONS

Exposure to PM_2.5 adversely affects semen quality, specifically lower sperm motility, in fertile men.

Effects of glufosinate-ammonium on male reproductive health: Focus on epigenome and transcriptome in mouse sperm

Glufosinate-ammonium (GLA) is a widely used herbicide with emerging concern over its neural and reproductive toxicity. To uncover potential effects of GLA on male reproductive health in mammals, adult male C57BL/6J mice were administered 0.2 mg/kg·d GLA for 5 weeks. After examination on fertility, testis histology and semen quality in the GLA group, we performed deep sequencing to identify repressive epigenetic marks including DNA methylation and histone modifications (H3K27me3 and H3K9me3), together with mRNA transcript levels in sperm. Then, we integrated multi-omics sequencing data to comprehensively explore GLA-induced epigenetic and transcriptomic alterations. We found no significant difference either on fertility, testis histology or semen quality-related indicators. As for epigenome, the protein level of H3K27me3 was significantly increased in GLA sperm. Next generation sequencing showed alterations of these epigenetic marks and extensive transcription inhibition in sperm. These differential repressive marks were mainly distributed at intergenic regions and introns. According to results by Gene Ontology enrichment analysis, both differentially methylated and expressed genes were mainly enriched in pathways related to synapse organization. Subtle differences in genomic imprinting were also observed between the two groups. These results suggested that GLA predominantly impaired sperm epigenome and transcriptome in mice, with little effect on fertility, testis histology or semen quality. Further studies on human sperm using similar strategies need to be conducted for a better understanding of the male reproductive toxicity of GLA.

Exposure and perception of PM2.5 pollution on the mental stress of pregnant women

Prenatal exposure to ambient PM_2.5 has been proved to be related to pregnant women's physical health and birth outcomes. However, the damage from air pollution on pregnant women's mental health has not been fully discussed. A case-control study was conducted to evaluate the effects of PM_2.5 exposure and risk perception on the mental stress of pregnant women. A total of 605 pregnant women, including 403 high symptoms of stress cases and 202 matched controls, were recruited from January 2018 to December 2018 in Nanjing, among which 313 high symptoms of stress cases and 144 matched controls were included in the analysis. Meaningfully high symptoms of anxiety were defined with a score of 6 points or greater on the phobic anxiety subscale of the Crown-Crisp index. We found that the PM_2.5 effect perceived by the case group was significantly higher than the control group, and the PM_2.5 exposure of the case group was also significantly higher than that of the control group. Binary logistic regression showed that for each increase in unit of PM_2.5 exposure, the risk of pregnant women suffering from high mental stress increased by 13.76% (95 %CI: 8.26-19.53%). Through path analysis modeling, we found that in the case group, perceived indoor attributions not only had a direct impact on mental stress (p < 0.001), but also played a key mediating role in the impact of average daily dose of PM_2.5 on mental stress (p < 0.001). The high level of mental stress is not only affected by objective exposure, but also by subjective perceptions in the case group. Considering the significant effect of PM_2.5 exposure on mental stress, pregnant women are recommended to spend appropriate amounts of time outdoors during clean air days. In addition, the mediating role of risk perception cannot be ignored. It is necessary to reassure pregnant women not to become overly concerned about the risk of PM_2.5 pollution and reduce their psychological burden.

Insight Into the Potential Value of Gut Microbial Signatures for Prediction of Gestational Anemia

The gut microbiota alternations are associated with gestational anemia (GA); however, limited predictive value for the subsequent incidence of anemia in normal gestational women has been obtained. We sought to rigorously characterise gut dysbiosis in subjects with GA and explored the potential predictive value of novel microbial signatures for the risk of developing GA. A prospective cohort of subjects with GA (n = 156) and healthy control (n = 402), all of whom were free of GA in the second trimester, by 16S rRNA gene sequencing was conducted. Microbial signatures altered dramatically in GA compared with healthy control in the second trimester. Megamonas, Veillonella, and Haemophilus were confirmed to show differential abundances in GA after adjusting for covariates. On the contrary, Lachnospiraceae and Blautia were enriched in control. Microbial co-abundance group (CAG) network was constructed. Prospectively, CAG network relatively accurately predicted upcoming GA in normal pregnant women with an AUC of 0.7738 (95%CI: 0.7171, 0.8306) and the performance was further validated in Validation set (0.8223, 95%CI: 0.7573, 0.8874). Overall, our study demonstrated that alterations in the gut microbial community were associated with anemia in pregnancy and microbial signatures could accurately predict the subsequent incidence of anemia in normal pregnant women. Our findings provided new insights into understanding the role of gut microbiota in GA, identifying high-risk individuals, and modulating gut microbiota as a therapeutic target, thus improving quality of life and well-being of women and children.

Contribution of trace element exposure to gestational diabetes mellitus through disturbing the gut microbiome

BACKGROUND

A healthy gut microbiome is critical for glucose metabolism during pregnancy. In vivo studies indicate that trace element affects the composition and function of the gut microbiome and potentially leads to metabolic disorders but their relationships are largely unknown. We aimed to investigate whether the gut microbiome plays a role in the relationship between trace element exposure and gestational diabetes mellitus (GDM).

METHODS

In a prospective cohort study, serum levels of 22 trace elements and the fecal gut microbiome composition were assessed in 837 pregnant women in the second trimester between 22 and 24 weeks of pregnancy prior to GDM diagnosis. Regression and mediation analysis were used to explore the link between element exposure, the gut microbiome, and GDM.

RESULTS

128 pregnant women (15.3%) were diagnosed with GDM. No individual trace elements were found significantly associated with GDM. In contrast, the composition of the gut microbiome was dramatically altered in women later diagnosed with GDM and characterized by lower alpha diversity and lower abundance of co-abundance groups (CAGs) composed of genera belonging to Ruminococcaceae, Coriobacteriales, and Lachnospiraceae. Rubidium (Rb) was positively associated with alpha diversity indices while mercury (Hg) and vanadium (V) showed negative associations. Elements including rubidium (Rb), thallium (Tl), arsenic (As), and antimony (Sb) were significantly correlated with GDM-related CAGs and mediation analysis revealed that Rb and Sb were inversely related to GDM risk by altering abundance levels of CAGs enriched for Lachnospiraceae, Coriobacteriales, and Ruminococcaceae.

CONCLUSION

Our study indicates that trace element exposure is associated with specific gut microbiome features that may contribute to GDM development, which could provide a new avenue for intervening in environmental exposure-related GDM.