Differential impact of prenatal PTSD symptoms and preconception trauma exposure on placental NR3C1 and FKBP5 methylation.

Perinatal stress is associated with altered placental methylation, which plays a critical role in fetal development and infant outcomes. This proof-of-concept pilot study investigated the impact of lifetime trauma exposure and perinatal PTSD symptoms on epigenetic regulation of placenta glucocorticoid signaling genes (NR3C1 and FKBP5). Lifetime trauma exposure and PTSD symptoms during pregnancy were assessed in a racially/ethnically diverse sample of pregnant women (N = 198). Participants were categorized into three groups: (1) No Trauma (-T); (2) Trauma, No Symptoms (T - S); and (3) Trauma and Symptoms (T + S). Placental tissue was analyzed via bisulfite pyrosequencing for degree of methylation at the NR3C1 promoter and FKBP5 regulatory regions. Analyses of covariance were used to test group differences in percentages of NR3C1 and FKBP5 methylation overall and at each CpG site. We found a significant impact of PTSD symptoms on placental NR3C1 methylation. Compared to the -T group, the T + S group had greater NR3C1 methylation overall and at CpG6, CpG8, CpG9, and CpG13, but lower methylation at CpG5. The T + S group had significantly higher NR3C1 methylation overall and at CpG8 compared to the T - S group. There were no differences between the T - S group and - T group. Additionally, no group differences emerged for FKBP5 methylation. Pregnant trauma survivors with PTSD symptoms exhibited differential patterns of placental NR3C1 methylation compared to trauma survivors without PTSD symptoms and pregnant women unexposed to trauma. Results highlight the critical importance of interventions to address the mental health of pregnant trauma survivors.

Neurodevelopmental and behavioral outcomes of very preterm infants: latent profile analysis in the Environmental influences on Child Health Outcomes (ECHO) Program.

BACKGROUND: Very preterm infants are at high risk for neurodevelopmental impairments. We used a child-centered approach (latent profile analysis [LPA]) to describe 2-year neurobehavioral profiles for very preterm infants based on cognitive, motor, and behavioral outcomes. We hypothesized that distinct outcome profiles would differ in the severity and co-occurrence of neurodevelopmental and behavioral impairment. METHODS: We studied children born <33 weeks' gestation from the Environmental influences on Child Health Outcomes Program with at least one neurobehavioral assessment at age 2 (Bayley Scales of Infant and Toddler Development, Child Behavior Checklist, Modified Checklist for Autism in Toddlers, cerebral palsy diagnosis). We applied LPA to identify subgroups of children with different patterns of outcomes. RESULTS: In 2036 children (52% male; 48% female), we found four distinct neurobehavioral profiles. Most children (~85%) were categorized into one of two profiles characterized by no/mild neurodevelopmental delay and a low prevalence of behavioral problems. Fewer children (~15%) fell into one of two profiles characterized by severe neurodevelopmental impairments. One profile consisted of children (5%) with co-occurring neurodevelopmental impairment and behavioral problems. CONCLUSION: Child-centered approaches provide a comprehensive, parsimonious description of neurodevelopment following preterm birth and can be useful for clinical and research purposes. IMPACT: Most research on outcomes for children born very preterm have reported rates of impairment in single domains. Child-centered approaches describe profiles of children with unique combinations of cognitive, motor, and behavioral strengths and weaknesses. We capitalized on data from the nationwide Environmental influences on Child Health Outcomes Program to examine these profiles in a large sample of children born <33 weeks gestational age. We found four distinct neurobehavioral profiles consisting of different combinations of cognitive, motor, and behavioral characteristics. This information could aid in the development of clinical interventions that target different profiles of children with unique developmental needs.

Epigenetic associations in HPA axis genes related to bronchopulmonary dysplasia and antenatal steroids.

BACKGROUND: Bronchopulmonary dysplasia (BPD), a common morbidity among very preterm infants, is associated with chronic disease and neurodevelopmental impairments. A hypothesized mechanism for these outcomes lies in altered glucocorticoid (GC) activity. We hypothesized that BPD and its treatments may result in epigenetic differences in the hypothalamic-pituitary-adrenal (HPA) axis, which is modulated by GC, and could be ascertained using an established GC risk score and DNA methylation (DNAm) of HPA axis genes. METHODS: DNAm was quantified from buccal tissue (ECHO-NOVI) and from neonatal blood spots (ELGAN ECHO) via the EPIC microarray. Prenatal maternal characteristics, pregnancy complication, and neonatal medical complication data were collected from medical record review and maternal interviews. RESULTS: The GC score was not associated with steroid exposure or BPD. However, six HPA genes involved in stress response regulation demonstrated differential methylation with antenatal steroid exposure; two CpGs within FKBP5 and POMC were differentially methylated with BPD severity. These findings were sex-specific in both cohorts; males had greater magnitude of differential methylation within these genes. CONCLUSIONS: These findings suggest that BPD severity and antenatal steroids are associated with DNAm at some HPA genes in very preterm infants and the effects appear to be sex-, tissue-, and age-specific. IMPACT: This study addresses bronchopulmonary dysplasia (BPD), an important health outcome among preterm neonates, and interrogates a commonly studied pathway, the hypothalamic-pituitary-adrenal (HPA) axis. The combination of BPD, the HPA axis, and epigenetic markers has not been previously reported. In this study, we found that BPD itself was not associated with epigenetic responses in the HPA axis in infants born very preterm; however, antenatal treatment with steroids was associated with epigenetic responses.

Examining the Biological Impacts of Parent-Child Relationship Dynamics on Preschool-Aged Children who have Experienced Adversity.

Parent-child relationship dynamics have been shown to predict socioemotional and behavioral outcomes for children, but little is known about how they may affect biological development. The aim of this study was to test if observational assessments of parent-child relationship dynamics (cohesion, enmeshment, and disengagement) were associated with three biological indices of early life adversity and downstream health risk: (1) methylation of the glucocorticoid receptor gene (NR3C1), (2) telomere attrition, and (3) mitochondrial biogenesis, indexed by mitochondrial DNA copy number (mtDNAcn), all of which were measured in children's saliva. We tested hypotheses using a sample of 254 preschool-aged children (M age = 51.04 months) with and without child welfare-substantiated maltreatment (52% with documented case of moderate-severe maltreatment) who were racially and ethnically diverse (17% Black, 40% White, 23% biracial, and 20% other races; 45% Hispanic) and from primarily low-income backgrounds (91% qualified for public assistance). Results of path analyses revealed that: (1) higher parent-child cohesion was associated with lower levels of methylation of NR3C1 exon 1D and longer telomeres, and (2) higher parent-child disengagement was associated with higher levels of methylation of NR3C1 exon 1D and shorter telomeres. Results suggest that parent-child relationship dynamics may have distinct biological effects on children.

Sexually dimorphic methylation patterns characterize the placenta and blood from extremely preterm newborns.

BACKGROUND: Health outcomes among children born prematurely are known to be sexually dimorphic, with male infants often more affected, yet the mechanism behind this observation is not clear. CpG methylation levels in the placenta and blood also differ by sex and are associated with adverse health outcomes. We contrasted CpG methylation levels in the placenta and neonatal blood (n = 358) from the Extremely Low Gestational Age Newborn (ELGAN) cohort based on the EPIC array, which assays over 850,000 CpG sites across the epigenome. Sex-specific epigenome-wide association analyses were conducted for the placenta and neonatal blood samples independently, and the results were compared to determine tissue-specific differences between the methylation patterns in males and females. All models were adjusted for cell type heterogeneity. Enrichment pathway analysis was performed to identify the biological functions of genes related to the sexually dimorphic CpG sites. RESULTS: Approximately 11,500 CpG sites were differentially methylated in relation to sex. Of these, 5949 were placenta-specific and 5361 were blood-specific, with only 233 CpG sites overlapping in both tissues. For placenta-specific CpG sites, 90% were hypermethylated in males. For blood-specific CpG sites, 95% were hypermethylated in females. In the placenta, keratinocyte differentiation biological pathways were enriched among the differentially methylated genes. No enrichment pathways were observed for blood. CONCLUSIONS: Distinct methylation patterns were observed between male and female children born extremely premature, and keratinocyte differentiation pathways were enriched in the placenta. These findings provide new insights into the epigenetic mechanisms underlying sexually dimorphic health outcomes among extremely premature infants.

Incidence rates of childhood asthma with recurrent exacerbations in the US Environmental influences on Child Health Outcomes (ECHO) program.

BACKGROUND: Descriptive epidemiological data on incidence rates (IRs) of asthma with recurrent exacerbations (ARE) are sparse. OBJECTIVES: This study hypothesized that IRs for ARE would vary by time, geography, age, and race and ethnicity, irrespective of parental asthma history. METHODS: The investigators leveraged data from 17,246 children born after 1990 enrolled in 59 US with 1 Puerto Rican cohort in the Environmental Influences on Child Health Outcomes (ECHO) consortium to estimate IRs for ARE. RESULTS: The overall crude IR for ARE was 6.07 per 1000 person-years (95% CI: 5.63-6.51) and was highest for children aged 2-4 years, for Hispanic Black and non-Hispanic Black children, and for those with a parental history of asthma. ARE IRs were higher for 2- to 4-year-olds in each race and ethnicity category and for both sexes. Multivariable analysis confirmed higher adjusted ARE IRs (aIRRs) for children born 2000-2009 compared with those born 1990-1999 and 2010-2017, 2-4 versus 10-19 years old (aIRR = 15.36; 95% CI: 12.09-19.52), and for males versus females (aIRR = 1.34; 95% CI 1.16-1.55). Black children (non-Hispanic and Hispanic) had higher rates than non-Hispanic White children (aIRR = 2.51; 95% CI 2.10-2.99; and aIRR = 2.04; 95% CI: 1.22-3.39, respectively). Children born in the Midwest, Northeast and South had higher rates than those born in the West (P < .01 for each comparison). Children with a parental history of asthma had rates nearly 3 times higher than those without such history (aIRR = 2.90; 95% CI: 2.43-3.46). CONCLUSIONS: Factors associated with time, geography, age, race and ethnicity, sex, and parental history appear to influence the inception of ARE among children and adolescents.

Human placental microRNAs dysregulated by cadmium exposure predict neurobehavioral outcomes at birth.

BACKGROUND: Prenatal cadmium (Cd) exposure has been implicated in both placental toxicity and adverse neurobehavioral outcomes. Placental microRNAs (miRNAs) may function to developmentally program adverse pregnancy and newborn health outcomes in response to gestational Cd exposure. METHODS: In a subset of the Rhode Island Child Health Study (RICHS, n = 115) and the New Hampshire Birth Cohort Study (NHBCS, = 281), we used small RNA sequencing and trace metal analysis to identify Cd-associated expression of placental miRNAs using negative binomial generalized linear models. We predicted mRNAs targeted by Cd-associated miRNAs and relate them to neurobehavioral outcomes at birth through the integration of transcriptomic data and summary scores from the NICU Network Neurobehavioral Scale (NNNS). RESULTS: Placental Cd concentrations are significantly associated with the expression level of five placental miRNAs in NHBCS, with similar effect sizes in RICHS. These miRNA target genes overrepresented in nervous system development, and their expression is correlated with NNNS metrics suggestive of atypical neurobehavioral outcomes at birth. CONCLUSIONS: Gestational Cd exposure is associated with the expression of placental miRNAs. Predicted targets of these miRNAs are involved in nervous system development and may also regulate placental physiology, allowing their dysregulation to modify developmental programming of early life health outcomes. IMPACT: This research aims to address the poor understanding of the molecular mechanisms governing adverse pregnancy and newborn health outcomes in response to Gestational cadmium (Cd) exposure. Our results outline a robust relationship between Cd-associated placental microRNA expression and NICU Network Neurobehavioral Scales (NNNS) at birth indicative of atypical neurobehavior. This study utilized healthy mother-infant cohorts to describe the role of Cd-associated dysregulation of placental microRNAs as a potential mechanism by which adverse neurobehavioral outcomes are developmentally programmed.

Placental microRNAs relate to early childhood growth trajectories.

BACKGROUND: Poor placental function is a common cause of intrauterine growth restriction, which in turn is associated with increased risks of adverse health outcomes. Our prior work suggests that birthweight and childhood obesity-associated genetic variants functionally impact placental function and that placental microRNA are associated with birthweight. To address the influence of the placenta beyond birth, we assessed the relationship between placental microRNAs and early childhood growth. METHODS: Using the SITAR package, we generated two parameters that describe individual weight trajectories of children (0-5 years) in the New Hampshire Birth Cohort Study (NHBCS, n = 238). Using negative binomial generalized linear models, we identified placental microRNAs that relate to growth parameters (FDR < 0.1), while accounting for sex, gestational age at birth, and maternal parity. RESULTS: Genes targeted by the six growth trajectory-associated microRNAs are enriched (FDR < 0.05) in growth factor signaling (TGF/beta: miR-876; EGF/R: miR-155, Let-7c; FGF/R: miR-155; IGF/R: Let-7c, miR-155), calmodulin signaling (miR-216a), and NOTCH signaling (miR-629). CONCLUSIONS: Growth-trajectory microRNAs target pathways affecting placental proliferation, differentiation and function. Our results suggest a role for microRNAs in regulating placental cellular dynamics and supports the Developmental Origins of Health and Disease hypothesis that fetal environment can have impacts beyond birth. IMPACT: We found that growth trajectory associated placenta microRNAs target genes involved in signaling pathways central to the formation, maintenance and function of placenta; suggesting that placental cellular dynamics remain critical to infant growth to term and are under the control of microRNAs. Our results contribute to the existing body of research suggesting that the placenta plays a key role in programming health in the offspring. This is the first study to relate molecular patterns in placenta, specifically microRNAs, to early childhood growth trajectory.

CpG methylation patterns in placenta and neonatal blood are differentially associated with neonatal inflammation.

BACKGROUND: Infants born extremely premature are at increased risk for health complications later in life for which neonatal inflammation may be a contributing biological driver. Placental CpG methylation provides mechanistic information regarding the relationship between prenatal epigenetic programming, prematurity, neonatal inflammation, and later-in-life health. METHODS: We contrasted CpG methylation in the placenta and neonatal blood spots in relation to neonatal inflammation in the Extremely Low Gestational Age Newborn (ELGAN) cohort. Neonatal inflammation status was based on the expression of six inflammation-related proteins, assessed as (1) day-one inflammation (DOI) or (2) intermittent or sustained systemic inflammation (ISSI, inflammation on ≥2 days in the first 2 postnatal weeks). Epigenome-wide CpG methylation was assessed in 354 placental samples and 318 neonatal blood samples. RESULTS: Placental CpG methylation displayed the strongest association with ISSI (48 CpG sites) but was not associated with DOI. This was in contrast to CpG methylation in blood spots, which was associated with DOI (111 CpG sites) and not with ISSI (one CpG site). CONCLUSIONS: Placental CpG methylation was strongly associated with ISSI, a measure of inflammation previously linked to later-in-life cognitive impairment, while day-one neonatal blood methylation was associated with DOI. IMPACT: Neonatal inflammation increases the risk of adverse later-life outcomes, especially in infants born extremely preterm. CpG methylation in the placenta and neonatal blood spots were evaluated in relation to neonatal inflammation assessed via circulating proteins as either (i) day-one inflammation (DOI) or (ii) intermittent or sustained systemic inflammation (ISSI, inflammation on ≥2 days in the first 2 weeks). Tissue specificity was observed in epigenetic-inflammatory relationships: placental CpG methylation was associated with ISSI, neonatal blood CpG methylation was associated with DOI. Supporting the placental origins of disease framework, placental epigenetic patterns are associated with a propensity for ISSI in neonates.

Prenatal and perinatal factors associated with neonatal neurobehavioral profiles in the ECHO Program.

BACKGROUND: Single-cohort studies have identified distinct neurobehavioral profiles that are associated with prenatal and neonatal factors based on the NICU Network Neurobehavioral Scale (NNNS). We examined socioeconomic, medical, and substance use variables as predictors of NNNS profiles in a multi-cohort study of preterm and term-born infants with different perinatal exposures. METHODS: We studied 1112 infants with a neonatal NNNS exam from the Environmental influences on Child Health Outcomes (ECHO) consortium. We used latent profile analysis to characterize infant neurobehavioral profiles and generalized estimating equations to determine predictors of NNNS profiles. RESULTS: Six distinct neonatal neurobehavioral profiles were identified, including two dysregulated profiles: a hypo-aroused profile (16%) characterized by lethargy, hypotonicity, and nonoptimal reflexes; and a hyper-aroused profile (6%) characterized by high arousal, excitability, and stress, with low regulation and poor movement quality. Infants in the hypo-aroused profile were more likely to be male, have younger mothers, and have mothers who were depressed prenatally. Infants in the hyper-aroused profile were more likely to be Hispanic/Latino and have mothers who were depressed or used tobacco prenatally. CONCLUSIONS: We identified two dysregulated neurobehavioral profiles with distinct perinatal antecedents. Further understanding of their etiology could inform targeted interventions to promote positive developmental outcomes. IMPACT: Prior research on predictors of neonatal neurobehavior have included single-cohort studies, which limits generalizability of findings. In a multi-cohort study of preterm and term-born infants, we found six distinct neonatal neurobehavioral profiles, with two profiles being identified as dysregulated. Hypo- and hyper-aroused neurobehavioral profiles had distinct perinatal antecedents. Understanding perinatal factors associated with dysregulated neurobehavior could help promote positive developmental outcomes.

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.

Exposure to Contemporary and Emerging Chemicals in Commerce among Pregnant Women in the United States: The Environmental influences on Child Health Outcome (ECHO) Program.

Prenatal chemical exposures can influence maternal and child health; however, few industrial chemicals are routinely biomonitored. We assessed an extensive panel of contemporary and emerging chemicals in 171 pregnant women across the United States (U.S.) and Puerto Rico in the Environmental influences on Child Health Outcomes (ECHO) Program. We simultaneously measured urinary concentrations of 89 analytes (103 total chemicals representing 73 parent compounds) in nine chemical groups: bactericides, benzophenones, bisphenols, fungicides and herbicides, insecticides, organophosphate esters (OPEs), parabens, phthalates/alternative plasticizers, and polycyclic aromatic hydrocarbons (PAHs). We estimated associations of creatinine-adjusted concentrations with sociodemographic and specimen characteristics. Among our diverse prenatal population (60% non-Hispanic Black or Hispanic), we detected 73 of 89 analytes in ≥1 participant and 36 in >50% of participants. Five analytes not currently included in the U.S. biomonitoring were detected in ≥90% of samples: benzophenone-1, thiamethoxam, mono-2-(propyl-6-carboxy-hexyl) phthalate, monocarboxy isooctyl phthalate, and monohydroxy-iso-decyl phthalate. Many analyte concentrations were higher among women of Hispanic ethnicity compared to those of non-Hispanic White women. Concentrations of certain chemicals decreased with the calendar year, whereas concentrations of their replacements increased. Our largest study to date identified widespread exposures to prevalent and understudied chemicals in a diverse sample of pregnant women in the U.S.

Association between placental toxic metal exposure and NICU Network Neurobehavioral Scales (NNNS) profiles in the Rhode Island Child Health Study (RICHS).

BACKGROUND: Prenatal exposure to heavy metals has been linked to a variety of adverse outcomes in newborn health and later life. Toxic metals such as cadmium (Cd), manganese (Mn) and lead (Pb) have been implicated to negatively affect newborn neurobehavior. Placental levels of these metals may provide additional understandings on the link between prenatal toxic metal exposures and neurobehavioral performances in newborns. OBJECTIVE: To evaluate associations between placental concentrations of toxic metals and newborn neurobehavioral performance indicated through the NICU Network Neurobehavioral Scales (NNNS) latent profiles. METHOD: In the Rhode Island Child Health Study cohort (n = 625), newborn neurobehavioral performance was assessed with NNNS, and a latent profile analysis was used to define five discrete neurobehavioral profiles based on summary scales. Using multinomial logistic regression, we determined whether increased levels of placental toxic metals Cd, Mn and Pb associated with newborns assigned to the profile demonstrating atypical neurobehavioral performances. RESULTS: Every doubling in placenta Cd concentration was associated with increased odds of newborns belonging to the atypical neurobehavior profile (OR: 2.72, 95% CI [1.09, 6.79]). Detectable placental Pb also demonstrated an increased odds of newborns assignment to the atypical profile (OR: 3.71, 95% CI [0.97, 13.96]) compared to being in the typical neurobehavioral profile. CONCLUSIONS: Toxic metals Cd and Pb measured in placental tissue may adversely impact newborn neurobehavior. Utilizing the placenta as a prenatal toxic metal exposure biomarker is useful in elucidating the associated impacts of toxic metals on newborn health.

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.

Pre-diagnosis neutrophil-to-lymphocyte ratio and mortality in individuals who develop lung cancer.

PURPOSE: The neutrophil-to-lymphocyte ratio (NLR) is a marker of systemic inflammation that has been reported to be associated with survival after chronic disease diagnoses, including lung cancer. We hypothesized that the inflammatory profile reflected by pre-diagnosis NLR, rather than the well-studied pre-treatment NLR at diagnosis, may be associated with increased mortality after lung cancer is diagnosed in high-risk heavy smokers. METHODS: We examined associations between pre-diagnosis methylation-derived NLR (mdNLR) and lung cancer-specific and all-cause mortality in 279 non-small lung cancer (NSCLC) and 81 small cell lung cancer (SCLC) cases from the ß-Carotene and Retinol Efficacy Trial (CARET). Cox proportional hazards models were adjusted for age, sex, smoking status, pack years, and time between blood draw and diagnosis, and stratified by stage of disease. Models were run separately by histotype. RESULTS: Among SCLC cases, those with pre-diagnosis mdNLR in the highest quartile had 2.5-fold increased mortality compared to those in the lowest quartile. For each unit increase in pre-diagnosis mdNLR, we observed 22-23% increased mortality (SCLC-specific hazard ratio [HR] = 1.23, 95% confidence interval [CI]: 1.02, 1.48; all-cause HR = 1.22, 95% CI 1.01, 1.46). SCLC associations were strongest for current smokers at blood draw (Interaction Ps = 0.03). Increasing mdNLR was not associated with mortality among NSCLC overall, nor within adenocarcinoma (N = 148) or squamous cell carcinoma (N = 115) case groups. CONCLUSION: Our findings suggest that increased mdNLR, representing a systemic inflammatory profile on average 4.5 years before a SCLC diagnosis, may be associated with mortality in heavy smokers who go on to develop SCLC but not NSCLC.

Seasonally variant gene expression in full-term human placenta.

Seasonal exposures influence human health and development. The placenta, as a mediator of the maternal and fetal systems and a regulator of development, is an ideal tissue to understand the biological pathways underlying relationships between season of birth and later life health outcomes. Here, we conducted a differential expression (DE) analysis of season of birth in full-term human placental tissue to evaluate whether the placenta may be influenced by seasonal cues. Of the analyzed transcripts, 583 displayed DE between summer and winter births (False Discovery Rate [FDR] q < .05); among these, BHLHE40, MIR210HG, and HILPDA had increased expression among winter births (Bonferroni P < .05). Enrichment analyses of the seasonally variant genes between summer and winter births indicated overrepresentation of transcription factors HIF1A, VDR, and CLOCK, among others, and of GO term pathways related to ribosomal activity and infection. Additionally, a cosinor analysis found rhythmic expression for approximately 11.9% of all 17 664 analyzed placental transcripts. These results suggest that the placenta responds to seasonal cues and add to the growing body of evidence that the placenta acts as a peripheral clock, which may provide a molecular explanation for the extensive associations between season of birth and health outcomes.

DNA methylation in children with prenatal methamphetamine exposure and environmental adversity.

BACKGROUND: Methamphetamine (MA) use during pregnancy is a significant public health concern in the United States and affects long-term brain and behavioral development in children. We hypothesized that prenatal MA exposure would be related to greater DNA methylation of HSD11B2 and postnatal environmental stress. METHODS: The Infant Development, Environment, and Lifestyle Study (IDEAL), a longitudinal study of prenatal MA exposure enrolled mother-infant dyads in California, Hawaii, Iowa, and Oklahoma. Prenatal exposure was defined by maternal self-report and/or meconium toxicology screening. At ages 10-11 years, 100 children were assessed for drug exposure and DNA methylation of HSD11B2. Hierarchical linear models were used to determine the association between prenatal MA exposure and methylation of HSD11B2 at four CpG sites. RESULTS: Prenatal MA exposure (1.4% vs 0.31%, P < 0.01) and early childhood adversity (3.0 vs 2.0, P < 0.01) were associated with greater DNA methylation of HSD11B2 at the CpG2 site. The statistically significant effects of early childhood adversity (B = 0.11, P < 0.01) and prenatal MA exposure (B = 0.32, P = 0.03) on DNA methylation remained after adjusting for covariates. CONCLUSIONS: Prenatal MA exposure is related to postnatal childhood adversity and epigenetic alterations in HSD11B2, an important gene along the stress response pathway suggesting prenatal and postnatal programming effects. IMPACT: Prenatal methamphetamine exposure has been associated with developmental issues in newborns, yet little is known about the stress pathophysiology of methamphetamine on neurobehavior. This is the first evidence that prenatal methamphetamine exposure acts as a stressor, confirming the third pathophysiology of methamphetamine exposure.

Epigenome-wide analysis identifies genes and pathways linked to acoustic cry variation in preterm infants.

BACKGROUND: Preterm birth places infants at higher risk of adverse long-term behavioral and cognitive outcomes. Combining biobehavioral measures and molecular biomarkers may improve tools to predict the risk of long-term developmental delays. METHODS: The Neonatal Neurobehavior and Outcomes in Very Preterm Infants study was conducted at nine neonatal intensive care units between April 2014 and June 2016. Cries were recorded and buccal swabs collected during the neurobehavioral exam. Cry episodes were extracted and analyzed using a computer system and the data were summarized using factor analysis. Genomic DNA was extracted from buccal swabs, quantified using the Qubit Fluorometer, and aliquoted into standardized concentrations. DNA methylation was measured with the Illumina MethylationEPIC BeadArray, and an epigenome-wide association study was performed using cry factors (n = 335). RESULTS: Eighteen CpGs were associated with the cry factors at genome-wide significance (α = 7.08E - 09). Two CpG sites, one intergenic and one linked to gene TCF3 (important for B and T lymphocyte development), were associated with acoustic measures of cry energy. Increased methylation of TCF3 was associated with a lower energy-related cry factor. We also found that pitch (F0) and hyperpitch (F0 > 1 kHz) were associated with DNA methylation variability at 16 CpG sites. CONCLUSIONS: Acoustic cry characteristics are related to variation in DNA methylation in preterm infants. IMPACT: Preterm birth is a major public health problem and its long-term impact on health is not well understood. Cry acoustics, related to prematurity, has been linked to a variety of medical conditions. Biobehavioral measures and molecular biomarkers can improve prediction tools for long-term developmental risks of preterm birth. Variation in epigenetic modulation in preterm infants provides a potential link between preterm birth and unfavorable developmental outcomes.

Placental gene networks at the interface between maternal PM2.5 exposure early in gestation and reduced infant birthweight.

BACKGROUND: A growing body of evidence links maternal exposure to particulate matter <2.5 µM in diameter (PM2.5) and deviations in fetal growth. Several studies suggest that the placenta plays a critical role in conveying the effects of maternal PM2.5 exposure to the developing fetus. These include observed associations between air pollutants and candidate placental features, such as mitochondrial DNA content, DNA methylation and telomere length. However, gaps remain in delineating the pathways linking the placenta to air pollution-related health effects, including a comprehensive profiling of placental processes impacted by maternal PM2.5 exposure. In this study, we examined alterations in a placental transcriptome-wide network in relation to maternal PM2.5 exposure prior to and during pregnancy and infant birthweight. METHODS: We evaluated PM2.5 exposure and placental RNA-sequencing data among study participants enrolled in the Rhode Island Child Health Study (RICHS). Daily residential PM2.5 levels were estimated using a hybrid model incorporating land-use regression and satellite remote sensing data. Distributed lag models were implemented to assess the impact on infant birthweight due to PM2.5 weekly averages ranging from 12 weeks prior to gestation until birth. Correlations were assessed between PM2.5 levels averaged across the identified window of susceptibility and a placental transcriptome-wide gene coexpression network previously generated using the WGCNA R package. RESULTS: We identified a sensitive window spanning 12 weeks prior to and 13 weeks into gestation during which maternal PM2.5 exposure is significantly associated with reduced infant birthweight. Two placental coexpression modules enriched for genes involved in amino acid transport and cellular respiration were correlated with infant birthweight as well as maternal PM2.5 exposure levels averaged across the identified growth restriction window. CONCLUSION: Our findings suggest that maternal PM2.5 exposure may alter placental programming of fetal growth, with potential implications for downstream health effects, including susceptibility to cardiometabolic health outcomes and viral infections.

Genetic regulation of the placental transcriptome underlies birth weight and risk of childhood obesity.

GWAS identified variants associated with birth weight (BW), childhood obesity (CO) and childhood BMI (CBMI), and placenta is a critical organ for fetal development and postnatal health. We examined the role of placental transcriptome and eQTLs in mediating the genetic causes for BW, CO and CBMI, and applied integrative analysis (Colocalization and MetaXcan). GWAS loci associated with BW, CO, and CBMI were substantially enriched for placenta eQTLs (6.76, 4.83 and 2.26 folds, respectively). Importantly, compared to eQTLs of adult tissues, only placental eQTLs contribute significantly to both anthropometry outcomes at birth (BW) and childhood phenotypes (CO/CBMI). Eight, six and one transcripts colocalized with BW, CO and CBMI risk loci, respectively. Our study reveals that placental transcription in utero likely plays a key role in determining postnatal body size, and as such may hold new possibilities for therapeutic interventions to prevent childhood obesity.