Project description:Our previous research demonstrated that caffeine exposure on embryonic day (E) 8.5 increased body weight, altered cardiac morphology and function in adult male mice. However, these adverse effects were not observed in adenosine A1 receptor knockout (A1AR-/-) mice. Our hypothesis is that A1AR action mediates changes in DNA methylation patterns in mice exposed in utero to caffeine and that these changes in methylation lead to long-term effects in adult mice. To test this hypothesis, DNA Methylation 2.1M Deluxe Promoter Arrays (NimbleGen) were used to examine the methylation patterns of DNA isolated from adult left ventricles of the A1AR knockout line exposed to 20 mg/kg caffeine at E8.5 in utero. In A1AR+/+ mice, 4,896 hypermethylated and 2,823 hypomethylated regions were discovered in the left ventricles of the caffeine group compared to the normal saline group. In A1AR-/- mice, 1,024 hypermethylated and 1,757 hypomethylated regions were found in the caffeine group. The differentially methylated regions (DMRs) in the caffeine treated A1AR+/+ hearts mapped to 6,148 genes, 4,853 promoters, 4,111 primary transcripts, 816 CpG islands, and 98 miRNAs. Functional annotation clustering of genes revealed that many genes were involved in the development of hypertrophic cardiomyopathy and other heart diseases, which may explain our earlier findings of thickening of the left ventricular wall after in utero caffeine treatment. The methylation changes in several DMRs, mef2c, ins2, tnnt2, and myh6, were validated by bisulfite sequencing. In summary, in utero caffeine exposure caused DNA methylation changes in adult left ventricles and that these changes may be mediated by A1ARs. Pregnant mice were injected at embryonic day 8.5 with 0.9% NaCl (vehicle) or 20 mg/kg caffeine in vehicle i.p. Pups were born and raised until 8-10 weeks of age. Analysis was performed on the following groups vehicle A1AR+/+ (veh+/+), vehicle A1AR-/- (veh-/-), caffeine A1AR+/+ (caff+/+), and caffeine A1AR-/- (caff-/-). Genomic DNA from left ventricles of adult male mice was used. Two biological replicates were measured for each group.
Project description:Our previous research demonstrated that caffeine exposure on embryonic day (E) 8.5 increased body weight, altered cardiac morphology and function in adult male mice. However, these adverse effects were not observed in adenosine A1 receptor knockout (A1AR-/-) mice. Our hypothesis is that A1AR action mediates changes in DNA methylation patterns in mice exposed in utero to caffeine and that these changes in methylation lead to long-term effects in adult mice. To test this hypothesis, DNA Methylation 2.1M Deluxe Promoter Arrays (NimbleGen) were used to examine the methylation patterns of DNA isolated from adult left ventricles of the A1AR knockout line exposed to 20 mg/kg caffeine at E8.5 in utero. In A1AR+/+ mice, 4,896 hypermethylated and 2,823 hypomethylated regions were discovered in the left ventricles of the caffeine group compared to the normal saline group. In A1AR-/- mice, 1,024 hypermethylated and 1,757 hypomethylated regions were found in the caffeine group. The differentially methylated regions (DMRs) in the caffeine treated A1AR+/+ hearts mapped to 6,148 genes, 4,853 promoters, 4,111 primary transcripts, 816 CpG islands, and 98 miRNAs. Functional annotation clustering of genes revealed that many genes were involved in the development of hypertrophic cardiomyopathy and other heart diseases, which may explain our earlier findings of thickening of the left ventricular wall after in utero caffeine treatment. The methylation changes in several DMRs, mef2c, ins2, tnnt2, and myh6, were validated by bisulfite sequencing. In summary, in utero caffeine exposure caused DNA methylation changes in adult left ventricles and that these changes may be mediated by A1ARs.
Project description:In utero exposure to diesel exhaust particulates has been associated with increased adult susceptibility to heart failure in mice but the mechanisms by which this exposure promotes susceptibility are poorly understood. To identify potential transcriptional effects that mediate this susceptibility, we have performed RNA-seq analysis on adult hearts from mice exposed to diesel exhaust in utero and that have subsequently undergone transverse aortic constriction. We identified three target genes, Mir133a-2, Ptprf and Pamr1, which demonstrate dysregulation after exposure and aortic constriction. Examination of expression patterns in human heart tissue indicate a correlation between expression and heart failure. We subsequently examined for DNA methylation modifications at these candidate loci in neonatal cultured cardiac myocytes after in utero exposure to diesel exhaust and found that the promoter for Mir133a-2 is differentially methylated.
Project description:Developmental exposure to particulate matter air pollution is harmful to cardiovascular health, but the mechanisms by which this exposure mediates susceptibility to heart disease is poorly understood. We have previously shown, in a mouse model, that gestational exposure to diesel exhaust results in increased cardiac hypertrophy, fibrosis and susceptibility to heart failure in the adult offspring following transverse aortic constriction. In this study we have found hypomethylation of DNA in neonatal cardiomyocytes isolated from in utero DE exposed neonates. We have demonstrated that in utero exposure to diesel exhaust alters the neonatal cardiomyocyte transcriptional and epigenetic landscapes, as well as the metabolic capability of these cells. Understanding how exposure alters the developing heart through dysregulation of gene expression, metabolism and DNA methylation is vital for identifying therapeutic interventions for air pollution-related heart failure.
Project description:<p>Exposure to diabetes in utero is known to increase the offspring's likelihood of developing metabolic disease in adulthood, but the mechanisms involved are unknown. It has been proposed that early exposure to hyperglycemia and elevated insulin levels may lead to malprogramming of the fetus leading to the subsequent development of diabetes and obesity. Epigenetic modifications of the genome including DNA methylation, provide a plausible mechanism that allows for permanent propagation of gene activity states from one generation of cells to the next. </p> <p>The placenta, a fetal tissue easily accessible for study, is a complex organ that is essential in regulating fetal growth. The changes in placental nutrient transport associated with diabetes during pregnancy (DDP) have significant effects on the developing fetus, indicating that the placenta plays a critical role in fetal programming. The aim of our study was to investigate whether exposure to DDP alters genome-wide DNA methylation in the placenta obtained from term pregnancies resulting in differentially methylated loci of metabolically relevant genes and downstream changes in RNA and protein expression.</p>
Project description:Exposure to a high fat (HF) diet in utero is associated with increased incidence of cardiovascular disease, diabetes and metabolic syndrome later in life. However, the molecular basis of this enhanced susceptibility for metabolic disease is poorly understood. We performed genome-wide DNA methylation analysis to examine DNA methylation patterns in liver of offspring exposed to a Control or HF maternal diet. WT mice were fed a C (9.5% fat, 3.59 kcal/g) or HF (35.5% fat, 5.29 kcal/g) diet for 2 wk before mating, throughout pregnancy and lactation. Offspring were weaned to a low fat (5.6% fat, 3.4 kcal/g) diet and were sacrificed at 5wks of age. DNA methylation analysis revealed the majority of differentially methylated regions were hypermethylated in HF liver. Chromosomal distribution analysis showed hypermethylation hot spots on chromosomes 4 (atherosclerosis susceptibility QTL1) and 18 (insulin dependent susceptibility 21). Most of the hypermethylated genes in these hot spots are associated with cardiovascular system development and function. In summary, exposure to a maternal HF diet significantly alters the DNA methylation patterns in the liver of exposed offspring and contributes to programmed development of metabolic disease later in life.
Project description:RNA sequencing identifies differentially expressed genes in adult left ventricles following in utero caffeine exposure during embryonic day 6.5-9.5
Project description:Purpose: This study aimed to identify differentially expressed genes including alternative splice variants in embryonic ventricles following in utero caffeine treatment. Methods: Pregnant CD-1 mice were injected with 20 mg/kg of caffeine or vehicle control daily from embryonic day (E) 6.5-9.5. On E10.5, total RNA was isolated from embryonic ventricles and used for transcriptomic RNA sequencing with Illumina HiSeq 2000 (1X75bp). RNA-seq reads were aligned to the mouse genome (build mm10) with the Tophat for Illumina tool in the PSU galaxy platform. Counting and annotation of RNA-seq reads as well as alternative splicing analysis were performed with Partek Genomics Suite version 6.11. Differential expression of gene and transcript reads between treatments was analyzed with R package EdgeR. Genes/transcripts with false discovery rate (FDR) less than 0.05 and absolute fold change greater than 1.5 were considered as significant. Differentially expressed genes were defined as genes with altered expression at either gene or transcript level. Unique differentially expressed genes were identified by combining the results from annotations with the RefSeq Transcripts (2013-05-10) or Ensembl Transcripts release 71 databases. Results: Differential expression analysis revealed that 59 genes and 451 transcripts were significantly up-regulated, and 65 genes and 398 transcripts were down-regulated by prenatal caffeine treatment (fold change >1.5 or <-1.5; p-value with FDR<0.05). In total, 900 unique genes were identified to have altered expression either at the gene or transcription level. Further analysis with Partek GS revealed that 183 genes had abnormal alternative splicing at the exon level after in utero caffeine treatment. Conclusions: In utero caffeine exposure caused gene expression changes in embryonic ventricles and these changes may lead to long-term effects on cardiac morphology and function. mRNA profiles in E10.5 heart ventricles treated with caffeine were generated by deep sequencing (n=2 for vehicle, n=3 for caffeine), using Illumina HiSeq 2000.
Project description:Bisphenol-A (BPA) is an environmentally ubiquitous estrogen-like endocrine-disrupting compound. Exposure toBPAin utero hasbeen linked to female reproductive disorders, including endometrial hyperplasia and breast cancer. Estrogens are an etiological factor in many of these conditions. We sought to determine whether in utero exposure to BPA altered the global CpG methylation pattern of the uterine genome, subsequent gene expression, and estrogen response. Pregnant mice were exposed to an environmentally relevant dose of BPA or DMSO control. Uterine DNA and RNA were examined by using methylated DNA immunoprecipitation methylation microarray, expression microarray, and quantitative PCR. In utero BPA exposure altered the global CpG methylation profile of the uterine genome and subsequent gene expression. The effect on gene expression was not apparent until sexual maturation, which suggested that estrogen response was the primary alteration. Indeed, prenatal BPA exposure preferentially altered adult estrogen-responsive gene expression. Changes in estrogen response were accompanied by altered methylation that preferentially affected estrogen receptor-a (ERa)–binding genes. The majority of genes that demonstrated both altered expression and ERa binding had decreased methylation. BPA selectively altered the normal developmental programming of estrogen-responsive genes via modification of the genes that bind ERa. Gene– environment interactions driven by early life xenoestrogen exposure likely contributes to increased risk of estrogen related disease in adults.—Jorgensen, E. M.,Alderman,M.H., III,Taylor, H. S. Preferential epigenetic programmingof estrogen response after in utero xenoestrogen (bisphenol-A) exposure.