Project description:Background: Prenatal maternal stress (PNMS) predicts a wide variety of behavioral and physical outcomes in the offspring. Although epigenetic processes may be responsible for PNMS effects, human research is hampered by the lack of experimental methods that parallel controlled animal studies. Disasters, however, provide natural experiments that can provide models of prenatal stress. Methods: Five months after the 1998 Quebec ice storm we recruited women who had been pregnant during the disaster and assessed their degrees of objective hardship and subjective distress. Thirteen years later, we investigated DNA methylation profiling in T cells obtained from 36 of the children, and compared selected results with those from saliva samples obtained from the same children at age 8. Results: Prenatal maternal objective hardship was correlated with DNA methylation levels in 1675 CGs affiliated with 957 genes predominantly related to immune function; maternal subjective distress was uncorrelated. DNA methylation changes in SCG5 and LTA, both highly correlated with maternal objective stress, were comparable in T cells, peripheral blood mononuclear cells (PBMCs) and saliva cells. Conclusions: These data provide first evidence in humans supporting the conclusion that PNMS results in a lasting, broad, and functionally organized DNA methylation signature in several tissues in offspring. By using a natural disaster model, we can infer that the epigenetic effects found in Project Ice Storm are due to objective levels of hardship experienced by the pregnant woman rather than to her level of sustained distress. Bisulphite converted DNA from the 34 samples were hybridised to the Illumina Infinium 450k Human Methylation Beadchip v1.2
Project description:Background: Prenatal maternal stress (PNMS) predicts a wide variety of behavioral and physical outcomes in the offspring. Although epigenetic processes may be responsible for PNMS effects, human research is hampered by the lack of experimental methods that parallel controlled animal studies. Disasters, however, provide natural experiments that can provide models of prenatal stress. Methods: Five months after the 1998 Quebec ice storm we recruited women who had been pregnant during the disaster and assessed their degrees of objective hardship and subjective distress. Thirteen years later, we investigated DNA methylation profiling in T cells obtained from 36 of the children, and compared selected results with those from saliva samples obtained from the same children at age 8. Results: Prenatal maternal objective hardship was correlated with DNA methylation levels in 1675 CGs affiliated with 957 genes predominantly related to immune function; maternal subjective distress was uncorrelated. DNA methylation changes in SCG5 and LTA, both highly correlated with maternal objective stress, were comparable in T cells, peripheral blood mononuclear cells (PBMCs) and saliva cells. Conclusions: These data provide first evidence in humans supporting the conclusion that PNMS results in a lasting, broad, and functionally organized DNA methylation signature in several tissues in offspring. By using a natural disaster model, we can infer that the epigenetic effects found in Project Ice Storm are due to objective levels of hardship experienced by the pregnant woman rather than to her level of sustained distress.
Project description:The goal of this experiment was to assess transcriptional changes in isolated GABAergic progenitors to determine the mechanism by which prenatal exposure to cypermethrin and maternal stress alter their migration
Project description:In the study presented here, microRNA expression was profiled in blood samples from mothers of children with autism, with known stress exposure during pregnancy. 2500 mature microRNAs were examined. Thirty-four maternal blood samples were examined in this study. Samples were divided into five groups based on maternal SERT genotypes (LL/LS/SS) and prenatal stress level (High/Low).
Project description:Maternal exposure to social stress during pregnancy is associated with an increased risk of psychiatric disorders in the offspring in later life. How the effects of maternal social stress are transmitted to the developing foetus is unclear. Using a rat model of maternal social stress during pregnancy, we explored the mechanisms by which maternal stress is conveyed to the foetus and the potential for targeted treatment to prevent disease in the offspring. Maternal stress induced oxidative stress in the placenta, but not in the foetal brain, which was prevented by a single administration of nanoparticle-bound antioxidant prior to the stress exposure. Moreover, this antioxidant treatment prevented prenatal stress-induced anxiety-like behaviour in juvenile male offspring, along with neurological and gene expression changes in the offspring brain. In vitro, placental conditioned medium or foetal plasma from stressed pregnancies caused changes to cultured cortical neurons, similar to those observed in the brains of juvenile offspring exposed to prenatal stress, and were found to contain altered levels of extracellular microRNAs but not corticosterone. The present study highlights the crucial role of the placenta, and molecules secreted from the placenta, in foetal brain development and provides evidence of the potential for treatment that can prevent maternal stress-induced foetal programming of neurological disease.
Project description:Fetal alcohol spectrum disorder (FASD) is a common developmental behavioral disorder caused by maternal drinking during pregnancy. Children born with FASD often face additional stress, particularly maternal separation that adds yet additional deficits. The mechanism associated with this phenomenon is not known. Using a mouse model, prenatal ethanol exposure and maternal separation stress have resulted in behavioral deficits and the combination of treatments results in more than additive effects. In addition, behavioral alterations are associated with changes in hippocampal gene expression that persist into adulthood. What initiates and maintains these changes remains to be established and forms the focus of this research. Specifically, MeDIP-Seq was used to assess how changes in promoter DNA methylation are affected by the combination of prenatal ethanol exposure and maternal separation stress with the potential to affect gene expression. The novel results show different sets of genes implicated by promoter DNA methylation affected by both treatments independently, and a relatively unique set of genes affected by the combination of treatments. Prenatal ethanol exposure leads to altered promoter DNA methylation at genes important for brain function and transcriptional regulation. Maternal separation stress leads to changes at genes important for histone methylation and immune response, and the combination of two treatments results in DNA methylation changes at genes important for neuronal migration and immune response. Our dual results on gene expression and DNA methylation from the same samples have allowed comparison of the two observations. There is minimal reciprocal overlap between changes in promoter DNA methylation and gene expression, although overlapping genes tend to be critical for brain development and function. These results suggest that epigenetic mechanisms beyond promoter DNA methylation must be involved in lasting gene expression alterations leading to behavioral deficits implicated in FASD.
Project description:Fetal alcohol spectrum disorders (FASD) are common, seen in 1-5% of the population in the United States and Canada. Regrettably, children diagnosed with FASD are not likely to remain with their biological parents, facing early maternal separation and foster placements throughout childhood. We have modeled FASD in mice via prenatal alcohol exposure and further induce early life stress through maternal separation. We report an association between adult hippocampal gene expression and prenatal and postnatal treatment that is related to behavioral changes. Clustering of expression profiles through weighted gene co-expression network analysis (WGCNA) identifies a set of transcripts associated with anxiety-like behavior as well as treatment group. Genes in this module are overrepresented by genes involved in transcriptional regulation and other pathways related to neurodevelopment. Interestingly, one member of this module, Polr2a, polymerase (RNA) II (DNA directed) polypeptide A, is downregulated by the combination of prenatal ethanol and postnatal stress in an RNA-Seq experiment and qPCR validation. Together, transcriptional control is implicated as a potential underlying mechanism leading to anxiety-like behavior via environmental insults. Greater understanding of the role of prenatal alcohol exposure and postnatal stress in altering the hippocampal transcriptome in the hippocampus is warranted. Further research is required to elucidate the mechanism involved and use this insight towards early diagnosis and amelioration strategies involving children born with FASD.
Project description:Prenatal exposure to maternal stress and depression has been identified as a risk factor for adverse behavioral and neurodevelopmental outcomes in early childhood. However, the molecular mechanisms through which maternal psychopathology shapes offspring development remain poorly understood. We analyzed transcriptome-wide gene expression profiles of 149 UCB samples from neonates born to mothers with prenatal PTSD (n=20), depression (n=31) and PTSD with comorbid depression (PTSD/Dep; n=13), compared to neonates born to carefully matched trauma exposed controls without meeting PTSD criteria (TE; n=23) and healthy mothers (n=62). We also evaluated physiological and developmental measures in these infants at birth, six months and twenty-four months. A multistep analytic approach was used that specifically sought to: 1) identify dysregulated genes, molecular pathways and discrete groups of co-regulated gene modules in UCB associated with prenatal maternal psychopathologies; and 2) to determine the impact of perinatal PTSD and depression on early childhood development outcomes.
Project description:Whole transcript expression was profiled using the Affymetrix 1.0 array in human bronchial epithelial cells exposed to PM collected from Saudi Arabia for 1 or 4 days. The differentially expressed genes were identified and analyzed for enriched networks and pathways using Ingenuity Pathway Analysis (IPA). We have identified 140 and 230 genes that significantly changed more than 1.5 fold after PM exposure for 1 or 4 days, respectively. IPA analysis revealed that different exposure durations triggered distinct pathways. Genes involved in NRF2-mediated response to oxidative stress were up-regulated after 1 day exposure. In contrast, cells exposed for 4 days exhibited significantly changes in genes related to cholesterol and lipid synthesis pathways. We analyzed gene expression profiles from 12 samples collected at two different time points, including 2 untreated controls, 2 normal PM treated samples and 2 storm PM treated samples for each time point.