Genome-wide association meta-analysis identifies pleiotropic risk loci for aerodigestive squamous cell cancers.

Squamous cell carcinomas (SqCC) of the aerodigestive tract have similar etiological risk factors. Although genetic risk variants for individual cancers have been identified, an agnostic, genome-wide search for shared genetic susceptibility has not been performed. To identify novel and pleotropic SqCC risk variants, we performed a meta-analysis of GWAS data on lung SqCC (LuSqCC), oro/pharyngeal SqCC (OSqCC), laryngeal SqCC (LaSqCC) and esophageal SqCC (ESqCC) cancers, totaling 13,887 cases and 61,961 controls of European ancestry. We identified one novel genome-wide significant (Pmeta<5x10-8) aerodigestive SqCC susceptibility loci in the 2q33.1 region (rs56321285, TMEM273). Additionally, three previously unknown loci reached suggestive significance (Pmeta<5x10-7): 1q32.1 (rs12133735, near MDM4), 5q31.2 (rs13181561, TMEM173) and 19p13.11 (rs61494113, ABHD8). Multiple previously identified loci for aerodigestive SqCC also showed evidence of pleiotropy in at least another SqCC site, these include: 4q23 (ADH1B), 6p21.33 (STK19), 6p21.32 (HLA-DQB1), 9p21.33 (CDKN2B-AS1) and 13q13.1(BRCA2). Gene-based association and gene set enrichment identified a set of 48 SqCC-related genes rel to DNA damage and epigenetic regulation pathways. Our study highlights the importance of cross-cancer analyses to identify pleiotropic risk loci of histology-related cancers arising at distinct anatomical sites.

Associations between prenatal organophosphate pesticide exposure and placental gene networks.

BACKGROUND: Exposure to organophosphate (OP) pesticides during pregnancy has been linked to deficiencies of neurobehavioral development in childhood; however, the molecular mechanisms underlying this association remain elusive. The placenta plays a crucial role in protecting the fetus from environmental insults and safeguarding proper fetal development including neurodevelopment. The aim of our study is to evaluate changes in the placental transcriptome associated with prenatal OP exposure. METHODS: Pregnant farm workers from two agricultural districts in northern Thailand were recruited for the Study of Asian Women and Offspring's Development and Environmental Exposures (SAWASDEE) from 2017 to 2019. For 254 participants, we measured maternal urinary concentrations of six nonspecific dialkyl phosphates (DAP) metabolites in early, middle, and late pregnancy. In parallel, we profiled the term placental transcriptome from the same participants using RNA-Sequencing and performed Weighted Gene co-expression Network Analysis (WGCNA). Generalized linear regression modeling was used to examine associations of urinary OP metabolites and placental co-expression module eigenvalues. RESULTS: We identified 21 gene co-expression modules in the placenta. From the six DAP metabolites assayed, diethylphosphate (DEP) and diethylthiophosphate (DETP) were detected in more than 70% of the urine samples. Significant associations between DEP at multiple time points and two specific placental gene modules were observed. The 'black' module, enriched in genes involved in epithelial-to-mesenchymal transition (EMT) and hypoxia, was negatively associated with DEP in early (p = 0.034), and late pregnancies (p = 0.016). The 'lightgreen' module, enriched in genes involved in myogenesis and EMT, was negatively associated with DEP in late pregnancy (p = 0.010). We observed 2 hub genes (CELSR1 and PYCR1) of the 'black' module to be negatively associated with DEP in early and late pregnancies. CONCLUSIONS: Our results suggest that prenatal OP exposure may disrupt placental gene networks in a time-dependent manner. Such transcriptomic effects may lead to down-stream changes in placental function that ultimately affect the developing fetus.

Cross-sectional associations of maternal PFAS exposure on SARS-CoV-2 IgG antibody levels during pregnancy.

BACKGROUND: Perfluoroalkylated substances (PFAS) are man-made, persistent organic compounds with immune-modulating potentials. Given that pregnancy itself represents an altered state of immunity, PFAS exposure-related immunotoxicity is an important environmental factor to consider in SARS-CoV-2 infection during pregnancy as it may further affect humoral immune responses. AIM: To investigate the relationship between maternal plasma PFAS concentrations and SARS-CoV-2 antibody levels in a NYC-based pregnancy cohort. METHODS: Maternal plasma was collected from 72 SARS-CoV-2 IgG + participants of the Generation C Study, a birth cohort established at the beginning of the COVID-19 pandemic in New York City. Maternal SARS-CoV-2 anti-spike IgG antibody levels were measured using ELISA. A panel of 16 PFAS congeners were measured in maternal plasma using a targeted UHPLC-MS/MS-based assay. Spearman correlations and linear regressions were employed to explore associations between maternal IgG antibody levels and plasma PFAS concentrations. Weighted quantile sum (WQS) regression was also used to evaluate mixture effects of PFAS. Models were adjusted for maternal age, gestational age at which SARS-CoV-2 IgG titer was measured, COVID-19 vaccination status prior to IgG titer measurement, maternal race/ethnicity, parity, type of insurance and pre-pregnancy BMI. RESULTS: Our study population is ethnically diverse with an average maternal age of 32 years. Of the 16 PFAS congeners measured, nine were detected in more than 60% samples. Importantly, all nine congeners were negatively correlated with SARS-CoV-2 anti-spike IgG antibody levels; n-PFOA and PFHxS, PFHpS, and PFHxA reached statistical significance (p < 0.05) in multivariable analyses. When we examined the mixture effects using WQS, a quartile increase in the PFAS mixture-index was significantly associated with lower maternal IgG antibody titers (beta [95% CI] = -0.35 [-0.52, -0.17]). PFHxA was the top contributor to the overall mixture effect. CONCLUSIONS: Our study results support the notion that PFAS, including short-chain emerging PFAS, act as immunosuppressants during pregnancy. Whether such compromised immune activity leads to downstream health effects, such as the severity of COVID-19 symptoms, adverse obstetric outcomes or neonatal immune responses remains to be investigated.

PM2.5 exposure during pregnancy is associated with altered placental expression of lipid metabolic genes in a US birth cohort.

Inhalation of ambient PM2.5, shown to be able to cross the placenta, has been linked to adverse obstetric and postnatal metabolic health outcomes. The placenta regulates fetal growth and influences postnatal development via fetal programming. Placental gene expression may be influenced by intrauterine exposures to PM2.5. Herein, we explore whether maternal PM2.5 exposure during pregnancy alters placental gene expression related to lipid and glucose metabolism in a U.S. birth cohort, the Rhode Island Child Health Study (RICHS). Average PM2.5 exposure level was estimated linking residential addresses and satellite data across the three trimesters using spatio-temporal models. Based on Gene Ontology annotations, we curated a list of 657 lipid and glucose metabolism genes. We conducted a two-staged analysis by leveraging placental RNA-Seq data from 148 subjects to identify top dysregulated metabolic genes associated with PM2.5 (Phase I) and then validated the results in placental samples from 415 participants of the cohort using RT-qPCR (Phase II). Associations between PM2.5 and placental gene expression were explored using multivariable linear regression models in the overall population and in sex-stratified analyses. The average level of PM2.5 exposure across pregnancy was 8.0µg/m3, which is below the national standard of 12µg/m3. Phase I revealed that expression levels of 32 out of the curated list of 657 genes were significantly associated with PM2.5 exposure (FDR P<0.01), 28 genes showed differential expression modified by sex of the infant. Five of these genes (ABHD3, ATP11A, CLTCL1, ST6GALNAC4 and PSCA) were validated using RT-qPCR. Associations were stronger in placentas from male births compared to females, indicating a sex-dependent effect. These genes are involved in inflammation, lipid transport, cell-cell communication or cell invasion. Our results suggest that gestational PM2.5 exposure may alter placental metabolic function. However, whether it confers long-term programming effects postnatally, especially in a sex-specific matter, warrants further studies.

Urinary glyphosate concentration in pregnant women in relation to length of gestation.

Human exposure to glyphosate-based herbicides (GBH) is increasing rapidly worldwide. Most existing studies on health effects of glyphosate have focused on occupational settings and cancer outcomes and few have examined this common exposure in relation to the health of pregnant women and newborns in the general population. We investigated associations between prenatal glyphosate exposure and length of gestation in The Infant Development and the Environment Study (TIDES), a multi-center US pregnancy cohort. Glyphosate and its primary degradation product [aminomethylphosphonic acid (AMPA)] were measured in urine samples collected during the second trimester from 163 pregnant women: 69 preterm births (<37 weeks) and 94 term births, the latter randomly selected as a subset of TIDES term births. We examined the relationship between exposure and length of gestation using multivariable logistic regression models (dichotomous outcome; term versus preterm) and with weighted time-to-event Cox proportional hazards models (gestational age in days). We conducted these analyses in the overall sample and secondarily, restricted to women with spontaneous deliveries (n = 90). Glyphosate and AMPA were detected in most urine samples (>94 %). A shortened gestational length was associated with maternal glyphosate (hazard ratio (HR): 1.31, 95 % confidence interval (CI) 1.00-1.71) and AMPA (HR: 1.32, 95%CI: 1.00-1.73) only among spontaneous deliveries using adjusted Cox proportional hazards models. In binary analysis, glyphosate and AMPA were not associated with preterm birth risk (<37 weeks). Our results indicate widespread exposure to glyphosate in the general population which may impact reproductive health by shortening length of gestation. Given the increasing exposure to GBHs and the public health burden of preterm delivery, larger confirmatory studies are needed, especially in vulnerable populations such as pregnant women and newborns.

Evaluating shared genetic influences on nonsyndromic cleft lip/palate and oropharyngeal neoplasms.

It has been hypothesised that nonsyndromic cleft lip/palate (nsCL/P) and cancer may share aetiological risk factors. Population studies have found inconsistent evidence for increased incidence of cancer in nsCL/P cases, but several genes (e.g., CDH1, AXIN2) have been implicated in the aetiologies of both phenotypes. We aimed to evaluate shared genetic aetiology between nsCL/P and oral cavity/oropharyngeal cancers (OC/OPC), which affect similar anatomical regions. Using a primary sample of 5,048 OC/OPC cases and 5,450 controls of European ancestry and a replication sample of 750 cases and 336,319 controls from UK Biobank, we estimate genetic overlap using nsCL/P polygenic risk scores (PRS) with Mendelian randomization analyses performed to evaluate potential causal mechanisms. In the primary sample, we found strong evidence for an association between a nsCL/P PRS and increased odds of OC/OPC (per standard deviation increase in score, odds ratio [OR]: 1.09; 95% confidence interval [CI]: 1.04, 1.13; p = .000053). Although confidence intervals overlapped with the primary estimate, we did not find confirmatory evidence of an association between the PRS and OC/OPC in UK Biobank (OR 1.02; 95% CI: 0.95, 1.10; p = .55). Mendelian randomization analyses provided evidence that major nsCL/P risk variants are unlikely to influence OC/OPC. Our findings suggest possible shared genetic influences on nsCL/P and OC/OPC.

The Ramazzini Institute 13-week pilot study glyphosate-based herbicides administered at human-equivalent dose to Sprague Dawley rats: effects on development and endocrine system.

BACKGROUND: Glyphosate-based herbicides (GBHs) are broad-spectrum herbicides that act on the shikimate pathway in bacteria, fungi, and plants. The possible effects of GBHs on human health are the subject of an intense public debate for both its potential carcinogenic and non-carcinogenic effects, including potential effects on the endocrine system The present pilot study examine whether exposure to GBHs at the dose of glyphosate considered to be "safe" (the US Acceptable Daily Intake - ADI - of 1.75 mg/kg bw/day), starting from in utero life, affect the development and endocrine system across different life stages in Sprague Dawley (SD) rats. METHODS: Glyphosate alone and Roundup Bioflow, a commercial brand of GBHs, were administered in drinking water at 1.75 mg/kg bw/day to F0 dams starting from the gestational day (GD) 6 (in utero) up to postnatal day (PND) 120. After weaning, offspring were randomly distributed in two cohorts: 8 M + 8F/group animals belonging to the 6-week cohort were sacrificed after puberty at PND 73 ± 2; 10 M + 10F/group animals belonging to the 13-week cohort were sacrificed at adulthood at PND 125 ± 2. Effects of glyphosate or Roundup exposure were assessed on developmental landmarks and sexual characteristics of pups. RESULTS: In pups, anogenital distance (AGD) at PND 4 was statistically significantly increased both in Roundup-treated males and females and in glyphosate-treated males. Age at first estrous (FE) was significantly delayed in the Roundup-exposed group and serum testosterone concentration significantly increased in Roundup-treated female offspring from the 13-week cohort compared to control animals. A statistically significant increase in plasma TSH concentration was observed in glyphosate-treated males compared with control animals as well as a statistically significant decrease in DHT and increase in BDNF in Roundup-treated males. Hormonal status imbalances were more pronounced in Roundup-treated rats after prolonged exposure. CONCLUSIONS: The present pilot study demonstrate that GBHs exposure, from prenatal period to adulthood, induced endocrine effects and altered reproductive developmental parameters in male and female SD rats. In particular, it was associated with androgen-like effects, including a statistically significant increase of AGDs in both males and females, delay of FE and increased testosterone in female.

The Ramazzini Institute 13-week pilot study on glyphosate and Roundup administered at human-equivalent dose to Sprague Dawley rats: effects on the microbiome.

BACKGROUND: Glyphosate-based herbicides (GBHs) are broad-spectrum herbicides that act on the shikimate pathway in bacteria, fungi, and plants. The possible effects of GBHs on human health are the subject of an intense public debate for both its potential carcinogenic and non-carcinogenic effects, including its effects on microbiome. The present pilot study examines whether exposure to GBHs at doses of glyphosate considered to be "safe" (the US Acceptable Daily Intake - ADI - of 1.75 mg/kg bw/day), starting from in utero, may modify the composition of gut microbiome in Sprague Dawley (SD) rats. METHODS: Glyphosate alone and Roundup, a commercial brand of GBHs, were administered in drinking water at doses comparable to the US glyphosate ADI (1.75 mg/kg bw/day) to F0 dams starting from the gestational day (GD) 6 up to postnatal day (PND) 125. Animal feces were collected at multiple time points from both F0 dams and F1 pups. The gut microbiota of 433 fecal samples were profiled at V3-V4 region of 16S ribosomal RNA gene and further taxonomically assigned and assessed for diversity analysis. We tested the effect of exposure on overall microbiome diversity using PERMANOVA and on individual taxa by LEfSe analysis. RESULTS: Microbiome profiling revealed that low-dose exposure to Roundup and glyphosate resulted in significant and distinctive changes in overall bacterial composition in F1 pups only. Specifically, at PND31, corresponding to pre-pubertal age in humans, relative abundance for Bacteriodetes (Prevotella) was increased while the Firmicutes (Lactobacillus) was reduced in both Roundup and glyphosate exposed F1 pups compared to controls. CONCLUSIONS: This study provides initial evidence that exposures to commonly used GBHs, at doses considered safe, are capable of modifying the gut microbiota in early development, particularly before the onset of puberty. These findings warrant future studies on potential health effects of GBHs in early development such as childhood.

Prenatal Programming of Infant Neurobehaviour in a Healthy Population.

BACKGROUND: Identifying the prenatal origins of mental conditions is of increasing interest, yet most studies have focused on high-risk populations and cannot disentangle prenatal and postnatal programming effects. Thus, we examined whether profiles of neurobehaviour indicative of future risk could be identified in healthy 1-3-day-old infants, and examined associations with perinatal risk factors. METHODS: Participants included 627 healthy mothers and term infants from a population-based US cohort. Neurobehaviour was assessed within 24-72 h after delivery with the NICU Network Neurobehavioural Scales (NNNS). A model-based clustering algorithm was used to derive neurobehavioural profiles from NNNS scores. Maternal health histories, pregnancy conditions and behaviours, labour/delivery factors, and infant attributes were examined in relation to the neurobehavioural profiles. RESULTS: Seven discrete neurobehavioural profiles were identified, including one average functioning profile, and two inversely patterned below and above average profiles. Higher pregnancy weight gain (OR 1.44, 95% CI 1.10, 1.88) and birthweight percentiles (OR 1.46, 95% CI 1.10, 1.95) were associated with greater odds of below average newborn neurobehaviour. Above average neurobehaviour was associated with experiencing longer gestations (OR 1.29, 95% CI 1.02, 1.64) and higher 5-min APGAR scores (OR 2.43, 95% CI 1.07, 5.52). Maternal pregnancy alcohol use (OR 0.54, 95% CI 0.33, 0.89), and fetal distress (OR 0.10, 95% CI 0.01, 0.72) were associated with lower likelihood of having average neurobehaviour. CONCLUSION: Distinct profiles of neurobehaviour can be derived in a healthy population of newborns, with different sets of perinatal factors predicting different patterns of neurobehaviour. These findings suggest a potential in utero origin for mental health risk.

The Role of Placental 11-Beta Hydroxysteroid Dehydrogenase Type 1 and Type 2 Methylation on Gene Expression and Infant Birth Weight.

Maternal stress has been linked to infant birth weight outcomes, which itself may be associated with health later in life. The placenta acts as a master regulator for the fetal environment, mediating intrauterine exposures to stress through the activity of genes regulating glucocorticoids, including the 11beta-hydroxysteroid dehydrogenase (HSD11B) type 1 and 2 genes, and so we hypothesized that variation in these genes will be associated with infant birth weight. We investigated DNA methylation levels at six sites across the two genes, as well as mRNA expression for each, and the relationship to infant birth weight. Logistic regressions correcting for potential confounding factors revealed a significant association between methylation at a single CpG site within HSD11B1 and being born large for gestational age. In addition, our analysis identified correlations between methylation and gene expression, including sex-specific transcriptional regulation of HSD11B2. Our work is one of the first comprehensive views of DNA methylation and expression in the placenta for both HSD11B types 1 and 2, linking epigenetic alterations with the regulation of fetal stress and birth weight outcomes.

Global and gene-specific DNA methylation across multiple tissues in early infancy: implications for children's health research.

An increasing number of population studies are assessing epigenetic variation in relation to early-life outcomes in tissues accessible to epidemiologic researchers. Epigenetic mechanisms are highly tissue specific, however, and it is unclear whether the variation observed in one of the tissue types is representative of other sources or whether the variation in DNA methylation is distinct, reflecting potential functional differences across tissues. To assess relations between DNA methylation in various samples from newborns and children in early infancy, we measured promoter or gene-body DNA methylation in matched term placenta, cord blood, and 3-6 mo saliva samples from 27 unrelated infants enrolled in the Rhode Island Child Health Study. We investigated 7 gene loci (KLF15, NR3C1, LEP, DEPTOR, DDIT4, HSD11B2, and CEBPB) and global methylation, using repetitive region LINE-1 and ALUYb8 sequences. We observed a great degree of interlocus, intertissue, and interindividual epigenetic variation in most of the analyzed loci. In correlation analyses, only cord blood NR3C1 promoter methylation correlated negatively with methylation in saliva. We conclude that placenta, cord blood, and saliva cannot be used as a substitute for one another to evaluate DNA methylation at these loci during infancy. Each tissue has a unique epigenetic signature that likely reflects their differential functions. Future studies should consider the uniqueness of these features, to improve epigenetic biomarker discovery and translation.

Association between maternal urinary arsenic species and infant cord blood leptin levels in a New Hampshire Pregnancy Cohort.

Leptin is an important pleiotropic hormone involved in the regulation of nutrient intake and energy expenditure, and is known to influence body weight in infants and adults. High maternal levels of arsenic have been associated with reduced infant birth weight, but the mechanism of action is not yet understood. This study aimed to investigate the association between in utero arsenic exposure and infant cord blood leptin concentrations within 156 mother-infant pairs from the New Hampshire Birth Cohort Study (NHBCS) who were exposed to low to moderate levels of arsenic through well water and diet. In utero arsenic exposure was obtained from maternal second trimester urinary arsenic concentration, and plasma leptin levels were assessed through immunoassay. Results indicate that urinary arsenic species concentrations were predictive of infant cord blood leptin levels following adjustment for creatinine, infant birth weight for gestational age percentile, infant sex, maternal pregnancy-related weight gain, and maternal education level amongst 149 white mother-infant pairs in multivariate linear regression models. A doubling or 100% increase in total urinary arsenic concentration (iAs+MMA+DMA) was associated with a 10.3% (95% CI: 0.8-20.7%) increase in cord blood leptin levels. A 100% increase in either monomethylarsonic acid (MMA) or dimethylarsinic acid (DMA) was also associated with an 8.3% (95% CI: -1.0-18.6%) and 10.3% (95% CI: 1.2-20.2%) increase in cord blood leptin levels, respectively. The association between inorganic arsenic (iAs) and cord blood leptin was of similar magnitude and direction as other arsenic species (a 100% increase in iAs was associated with a 6.5% (95% CI: -3.4-17.5%) increase in cord blood leptin levels), albeit not significant. These results suggest in utero exposure to low levels of arsenic influences cord blood leptin concentration and presents a potential mechanism by which arsenic may impact early childhood growth.

Methylation of exons 1D, 1F, and 1H of the glucocorticoid receptor gene promoter and exposure to adversity in preschool-aged children.

Epigenetic modifications to the genome are a key mechanism involved in the biological encoding of experience. Animal studies and a growing body of literature in humans have shown that early adversity is linked to methylation of the gene for the glucocorticoid receptor (GR), which is a key regulator of the hypothalamic-pituitary-adrenal axis as well as a broad range of physiological systems including metabolic and immune function. One hundred eighty-four families participated, including n = 74 with child welfare documentation of moderate-severe maltreatment in the past 6 months. Children ranged in age from 3 to 5 years, and were racially and ethnically diverse. Structured record review and interviews in the home were used to assess a history of maltreatment, other traumas, and contextual life stressors, and a composite variable assessed the number exposures to these adversities. Methylation of regions 1(D), 1(F), and 1(H) of the GR gene was measured via sodium bisulfite pyrosequencing. The composite measure of adversity was positively correlated with methylation at exons 1(D) and 1(F) in the promoter of the GR gene. Individual stress measures were significantly associated with a several CpG sites in these regions. GR gene methylation may be a mechanism of the biobehavioral effects of adverse exposures in young children.

Distinct patterns of DNA methylation in conventional adenomas involving the right and left colon.

Recent studies have shown two distinct non-CIMP methylation clusters in colorectal cancer, raising the possibility that DNA methylation, involving non-CIMP genes, may play a role in the conventional adenoma-carcinoma pathway. A total of 135 adenomas (65 left colon and 70 right colon) were profiled for epigenome-wide DNA methylation using the Illumina HumanMethylation450 BeadChip. A principal components analysis was performed to examine the association between variability in DNA methylation and adenoma location. Linear regression and linear mixed effects models were used to identify locus-specific differential DNA methylation in adenomas of right and left colon. A significant association was present between the first principal component and adenoma location (P=0.007), even after adjustment for subject age and gender (P=0.009). A total of 168 CpG sites were differentially methylated between right- and left-colon adenomas and these loci demonstrated enrichment of homeobox genes (P=3.0 × 10(-12)). None of the 168 probes were associated with CIMP genes. Among CpG loci with the largest difference in methylation between right- and left-colon adenomas, probes associated with PRAC (prostate cancer susceptibility candidate) gene showed hypermethylation in right-colon adenomas whereas those associated with CDX2 (caudal type homeobox transcription factor 2) showed hypermethylation in left-colon adenomas. A subgroup of left-colon adenomas enriched for current smokers (OR=6.1, P=0.004) exhibited a methylation profile similar to right-colon adenomas. In summary, our results indicate distinct patterns of DNA methylation, independent of CIMP genes, in adenomas of the right and left colon.

Maternal obesity and gestational diabetes are associated with placental leptin DNA methylation.

OBJECTIVE: In this study, we aimed to investigate relationships between maternal prepregnancy obesity and gestational diabetes mellitus and placental leptin DNA methylation. STUDY DESIGN: This study comprises data on 535 mother-infant dyads enrolled in the Rhode Island Child Health Study, a prospective cohort study of healthy term pregnancies. Prepregnancy body mass index was calculated from self-reported anthropometric measures and gestational diabetes mellitus diagnoses gathered from inpatient medical records. DNA methylation of the leptin promoter region was assessed in placental tissue collected at birth using quantitative bisulfite pyrosequencing. RESULTS: In a multivariable regression analysis adjusted for confounders, infants exposed to gestational diabetes mellitus had higher placental leptin methylation (ß = 1.89, P = .04), as did those demonstrating prepregnancy obesity (ß = 1.17, P = .06). Using a structural equations model, we observed that gestational diabetes mellitus is a mediator of the effects of prepregnancy obesity on placental leptin DNA methylation (ß = 0.81, 95% confidence interval, 0.27-2.71). CONCLUSION: Our results suggest that the maternal metabolic status before and during pregnancy can alter placental DNA methylation profile at birth and potentially contribute to metabolic programming of obesity and related conditions.

RNA-seq analysis reveals prenatal alcohol exposure is associated with placental inflammatory cells and gene expression.

BACKGROUND: Fetal alcohol spectrum disorders (FASD) are the most common preventable cause of birth defects and neurodevelopmental disorders worldwide. The placenta is the crucial interface between mother and fetus. Prenatal alcohol exposure (PAE) has been shown to alter placental structure and expression of genes in bulk placental tissue samples, but prior studies have not examined effects on placental cell-type composition or taken cell-type into consideration in transcriptome analyses. METHODS: We leveraged an existent placenta single-cell RNA-seq dataset to perform cell-type deconvolution of bulk placental RNA-seq data from 35 heavy drinking pregnant women and 33 controls in a prospective birth cohort in Cape Town, South Africa. We used bivariate analyses and multivariable adjusted linear regression models to assess the relation of PAE on inferred placental cell-type proportions. We also examined differential expression of inflammatory response genes and PAE, using multivariable adjusted linear models. RESULTS: Deconvolution analyses showed heterogeneous placenta cell-type composition in which stromal (27 %), endothelial (26 %) and cytotrophoblasts (18 %) were the predominant cell-types. PAE around conception was associated with a higher proportion of Hofbauer cells (B = 0.51, p = 0.035) in linear models adjusted for maternal age, infant sex, and gestational age. Among the 652 inflammatory genes examined, 35 were differential expressed in alcohol exposed placentas (FDR p < 0.05). CONCLUSIONS: Our findings suggest that heavy alcohol exposure during pregnancy can influence the proportion of fetal placental villi macrophages (Hofbauer cells) and increased expression of inflammatory genes. Future studies are needed to further characterize these effects and to assess the potential functional roles of placental inflammation in FASD.

Placental transcriptome variation associated with season, location, and urinary prenatal pyrethroid metabolites of Thai farm-working women.

Prenatal exposure to pyrethroids is linked to adverse health effects in early life and proper placental function is critical to fetal development. This study explores the impact of prenatal pyrethroid exposure, as well as factors impacting exposure and effect, on the placental transcriptome, to understand pyrethroid exposures' relationship to placental function. The study of Asian Women and their Offspring's Development and Environmental Exposures (SAWASDEE) recruited pregnant farm-working women from two agricultural districts in the Chiang Mai province of Thailand between 2017 and 2019. This cohort was predominantly exposed to cypermethrin (type II), alongside pyrethroids such as cyfluthrin (type II) and permethrin (type I). In 253 participants, maternal urinary pyrethroid metabolites, 3-phenoxybenzoic acid (PBA), cis-3-(2,2-Dichlorovinyl)-2,2-dimethylcyclopropane carboxylic acid (CDCCA), and trans-3-(2,2-Dichlorovinyl)-2,2-dimethylcyclopropane carboxylic acid (TDCCA) were measured in early, middle, and late pregnancy and adjusted for urinary creatinine. The placental transcriptome was analyzed using RNA-Seq. Using generalized linear regression, we identified differentially expressed genes (DEGs) associated with the sum of each metabolite across pregnancy, as well as those associated with location of residence and season of birth. Pathway and upstream transcription factor analyses were performed to examine potential mechanisms associated with DEGs. Notably, TDCCA and CDCCA levels peaked in late pregnancy, with significant regional differences, particularly higher levels in the Fang region. Placental gene expression analysis showed no DEGs associated with individual metabolites at FDR<0.05. However, 251 DEGs by location, implicating immune response and oxidative phosphorylation pathways, were identified, while season of birth was associated with 2585 DEGs, over-represented in fibrosis signaling and metabolism pathways. Finally, transcription factor analysis identified 226 and 282 transcription factors associated with location and season, respectively, related to cell proliferation, differentiation, and the immune system. These alterations may have significant implications for fetal development and other pathologic processes, highlighting the importance of monitoring environmental exposures during pregnancy.

The effect of SARS-CoV-2 infection and vaccination on Th17 and regulatory T cells in a pregnancy cohort in NYC.

Disturbances in T-cells, specifically the Th17/Treg balance, have been implicated in adverse pregnancy outcomes. We investigated these two T-cell populations following pre-pregnancy and pregnancy SARS-CoV-2 infection and COVID-19 vaccination in 351 participants from a pregnancy cohort in New York City (Generation C; 2020-2022). SARS-CoV-2 infection status was determined via laboratory or medical diagnosis and COVID-19 vaccination status via survey and electronic medical records data. Peripheral blood mononuclear cells (PBMCs) were collected at routine prenatal visits throughout gestation (median 108 days; IQR 67-191 days) with repeated measures for 104 participants (29.6%). T-cell populations CD4+/CD3+, Th17/CD4+, Treg/CD4+ and the Th17/Treg ratio were quantified using flow cytometry. Results showed that inter-individual differences are a main influencing factor in Th17 and Treg variance, however total variance explained remained small (R2 = 15-39%). Overall, Th17 and Treg populations were not significantly affected by SARS-CoV-2 infection during pregnancy in adjusted linear mixed models (p>0.05), however comparison of repeated measures among SARS-CoV-2 infected participants and non-infected controls suggests a relative increase of the Th17/Treg ratio following infection. In addition, the Th17/Treg ratio was significantly higher after SARS-CoV-2 infection prior to pregnancy (10-138 weeks) compared to controls (ß=0.48, p=0.003). COVID-19 vaccination was not associated with Th17 and Treg cells. Our findings suggest an impact of SARS-CoV-2 infection on the Th17/Treg ratio, likely depending on severity of infection, yet the observed trends and their potential consequences for pregnancy outcomes require further investigation. Our study contributes to growing evidence that COVID-19 vaccination during pregnancy does not lead to an exacerbated immune response.

Prenatal alcohol exposure is associated with changes in placental gene co-expression networks.

Alcohol consumption during pregnancy can result in a range of adverse postnatal outcomes among exposed children. However, identifying at-risk children is challenging given the difficulty to confirm prenatal alcohol exposure and the lack of early diagnostic tools. Placental surveys present an important opportunity to uncover early biomarkers to identify those at risk. Here, we report the first transcriptome-wide evaluation to comprehensively evaluate human placental pathways altered by fetal alcohol exposure. In a prospective longitudinal birth cohort in Cape Town, South Africa, we performed bulk tissue RNAseq in placenta samples from 32 women reporting heavy drinking during pregnancy and 30 abstainers/light drinkers. Weighted gene co-expression network analysis (WGCNA) and differential gene expression analysis were performed to assess associations between fetal alcohol exposure and placental gene expression patterns at a network-wide and single gene level, respectively. The results revealed altered expression in genes related to erythropoiesis and angiogenesis, which are implicated in established postnatal phenotypes related to alcohol exposure, including disruptions in iron homeostasis, growth, and neurodevelopment. The reported findings provide insights into the molecular pathways affected by prenatal alcohol exposure and highlight the potential of placental biomarkers for detecting and understanding the effects of alcohol on fetal development.

SARS-CoV-2 infection, inflammation and birth outcomes in a prospective NYC pregnancy cohort.

Associations between antenatal SARS-CoV-2 infection and pregnancy outcomes have been conflicting and the role of the immune system is currently unclear. This prospective cohort study investigated the interaction of antenatal SARS-CoV-2 infection, changes in cytokine and HS-CRP levels, birthweight and gestational age at birth. 2352 pregnant participants from New York City (2020-2022) were included. Plasma levels of interleukin (IL)-1ß, IL-6, IL-17A and high-sensitivity C-reactive protein (HS-CRP) were quantified in blood specimens obtained across pregnancy. Quantile and linear regression models were conducted to 1) assess the impact of antenatal SARS-CoV-2 infection, overall and by timing of detection of SARS-CoV-2 positivity (< 20 weeks versus ≥ 20 weeks), on birthweight and gestational age at delivery; 2) examine the relationship between SARS-CoV-2 infection and maternal immune changes during pregnancy. All models were adjusted for maternal demographic and obstetric factors and pandemic timing. Birthweight models were additionally adjusted for gestational age at delivery and fetal sex. Immune marker models were also adjusted for gestational age at specimen collection and multiplex assay batch. 371 (15.8%) participants were infected with SARS-CoV-2 during pregnancy, of which 98 (26.4%) were infected at < 20 weeks gestation. Neither SARS-CoV-2 infection in general nor in early or late pregnancy was associated with lower birthweight nor earlier gestational age at delivery. Further, we did not observe cytokine or HS-CRP changes in response to SARS-CoV-2 infection and thus found no evidence to support a potential association between immune dysregulation and the diversity in pregnancy outcomes following infection.