Project description:Ethanol is a well-known teratogen. While this teratogenic potential is well-characterized clinically, the mechanisms through which ethanol exposure results in developmental defects remain unclear. Here we use the zebrafish model to elucidate eye-specific mechanisms that may underlie ethanol-mediated microphthalmia (reduced eye size), using time-series microarray analysis of gene expression of eye tissues of embryos exposed to 1.5% ethanol vs. untreated embryos. We identified 62 genes differentially expressed in ethanol-treated as compared to control zebrafish eyes from all sampling times over the period of retinal neurogenesis (24-48 hours post-fertilization). Application of the EDGE (extraction of differential gene expression) algorithm identified over 3000 genes differentially expressed over developmental time in ethanol-treated embryo eyes as compared to untreated embryo eyes. These lists included several genes indicating a mis-regulated cellular stress response (heat shock response) due to ethanol exposure. Combined treatment with sub-threshold levels of ethanol and a morpholino (MO) targeting heat shock factor 1 (hsf-1) mRNA resulted in a microphthalmic phenotype, suggesting convergent molecular pathways. Manipulation of the heat shock response by thermal preconditioning partially prevented ethanol-mediated microphthalmia while maintaining Hsf-1 expression. Together these data are consistent with roles for reduced Hsf-1 in mediating microphthalmic effects of embryonic ethanol exposure in zebrafish.
Project description:Ethanol is a well-known teratogen. While this teratogenic potential is well-characterized clinically, the mechanisms through which ethanol exposure results in developmental defects remain unclear. Here we use the zebrafish model to elucidate eye-specific mechanisms that may underlie ethanol-mediated microphthalmia (reduced eye size), using time-series microarray analysis of gene expression of eye tissues of embryos exposed to 1.5% ethanol vs. untreated embryos. We identified 62 genes differentially expressed in ethanol-treated as compared to control zebrafish eyes from all sampling times over the period of retinal neurogenesis (24-48 hours post-fertilization). Application of the EDGE (extraction of differential gene expression) algorithm identified over 3000 genes differentially expressed over developmental time in ethanol-treated embryo eyes as compared to untreated embryo eyes. These lists included several genes indicating a mis-regulated cellular stress response (heat shock response) due to ethanol exposure. Combined treatment with sub-threshold levels of ethanol and a morpholino (MO) targeting heat shock factor 1 (hsf-1) mRNA resulted in a microphthalmic phenotype, suggesting convergent molecular pathways. Manipulation of the heat shock response by thermal preconditioning partially prevented ethanol-mediated microphthalmia while maintaining Hsf-1 expression. Together these data are consistent with roles for reduced Hsf-1 in mediating microphthalmic effects of embryonic ethanol exposure in zebrafish. time series, 9 samples, no replicates
Project description:The aim of reprotoxicity testing is to reveal adverse effects of chemicals and drugs on reproduction and on pre and postnatal fetal development. There is very limited data available on gene expression profiling for elucidation of the teratogenic effects of nongenotoxic teratogens. Therefore, research was undertaken to obtain knowledge on the molecular effects of MSC1096199 (previously known as EMD 82571), a calcium sensitizer that was abandoned in the preclinical development phase due to its teratogenic effects in some foetuses. Pregnant wistar rats were dose daily with either MSC1096199 (50 or 150 mg/kg) or Retinoic acid (10 mg/kg) on gestational days 6-17. Microarray experiment were performed using four different tissues (maternal liver, embryo liver (GD20), embryo bone (GD20), and whole embryo (GD12)) under four different conditions (vehicle, low dose and high dose of MSC1096199 and Retinoic acid) to determine the drug regulated genes. In the high dose treatment group, approximately 58% of the fetuses showed malformations i.e. exencephaly and agnathia, and toxicogenomics evidenced that the genes critically involved in osteogenesis, odontogenesis and extra cellular matrix components to be significantly regulated by MSC1096199, therefore providing a molecular rational for the observed teratogenic effects.
Project description:The aim of reprotoxicity testing is to reveal adverse effects of chemicals and drugs on reproduction and on pre and postnatal fetal development. There is very limited data available on gene expression profiling for elucidation of the teratogenic effects of nongenotoxic teratogens. Therefore, research was undertaken to obtain knowledge on the molecular effects of MSC1096199 (previously known as EMD 82571), a calcium sensitizer that was abandoned in the preclinical development phase due to its teratogenic effects in some foetuses. Pregnant wistar rats were dose daily with either MSC1096199 (50 or 150 mg/kg) or Retinoic acid (12 mg/kg) on gestational days 6-17. Microarray experiment were performed using four different tissues (maternal liver, embryo liver (GD20), embryo bone (GD20), and whole embryo (GD12)) under four different conditions (vehicle, low dose and high dose of MSC1096199 and Retinoic acid) to determine the drug regulated genes. In the high dose treatment group, approximately 58% of the fetuses showed malformations i.e. exencephaly and agnathia, and toxicogenomics evidenced that the genes critically involved in osteogenesis, odontogenesis and extra cellular matrix components to be significantly regulated by MSC1096199, therefore providing a molecular rational for the observed teratogenic effects.
Project description:The aim of reprotoxicity testing is to reveal adverse effects of chemicals and drugs on reproduction and on pre and postnatal fetal development. There is very limited data available on gene expression profiling for elucidation of the teratogenic effects of nongenotoxic teratogens. Therefore, research was undertaken to obtain knowledge on the molecular effects of MSC1096199 (previously known as EMD 82571), a calcium sensitizer that was abandoned in the preclinical development phase due to its teratogenic effects in some foetuses. Pregnant wistar rats were dose daily with either MSC1096199 (50 or 150 mg/kg) or Retinoic acid (10 mg/kg) on gestational days 6-17. Microarray experiment were performed using four different tissues (maternal liver, embryo liver (GD20), embryo bone (GD20), and whole embryo (GD12)) under four different conditions (vehicle, low dose and high dose of MSC1096199 and Retinoic acid) to determine the drug regulated genes. In the high dose treatment group, approximately 58% of the fetuses showed malformations i.e. exencephaly and agnathia, and toxicogenomics evidenced that the genes critically involved in osteogenesis, odontogenesis and extra cellular matrix components to be significantly regulated by MSC1096199, therefore providing a molecular rational for the observed teratogenic effects. Pregnant wistar rats were treated daily with the dose of either MSC1096199 (50 or 150 mg/kg) or Retinoic acid (10 mg/kg) on gestational days 6-17. Microarray experiment were performed using four different tissues (maternal liver, embryo liver, embryo bone, and whole embryo) under four different conditions (vehicle, low dose and high dose of MSC1096199 and Retinoic acid) to determine the drug regulated genes.
Project description:Mouse model for Fetal Alcohol Syndrome. Embryos exposed to alcohol in controlled environment to assess teratogenic effects. Fetal Alcohol Syndrome (FAS) is a leading developmental disorder. To date, a holistic view of molecular gene changes is largely unexplored. Using microarray analysis of whole embryo mouse culture with strict-control over alcohol-level, we found, directly related alcohol-metabolism, a reduction of retinol binding protein 1(Rbp1), and a, de novo expression of aldehyde dehydrogenase 1B1 (ALDH1B1). Remarkably, four key hemopoiesis genes (glycophorin A, adducin 2, beta-2 microglobulin, and ceruloplasmin) became absent, and many histone variants genes were reduced. Hypothesis-driven informatics analysis and intersection analysis of two independent experiments indicated that the altered genes are involved in cell growth, hemopoiesis, histone modification, eye and heart development, and a collective reduction in expression of growth factor genes (Igf1, Efemp1, Tieg, and Edil3) and neural specification genes (neurogenin, Sox 5, bHLHb5). Down-regulated neural specification phenotypes further supported the above findings. Further more, the gene expression profile indicated distinct subgroups which overlapped with the teratogenesis of the open- and the closed-neural tubes known in FAS. In summary, our data reveal genes alteration with causal potential for dysmorpology (e.g. retinoic acid, neuronal specification, and neurotrophic factors, and epigenetics related histone genes) and those downstream responsive genes related to alcohol metabolism, and developmental teratogenesis. Experiment Overall Design: Comparison of whole embryo gene expression after exposure to ethanol for 46 hours. Note 2 independent experiments completed.
Project description:Methylmercury (MeHg) is a teratogen with adverse effects on embryogenesis from fish to man. The adverse developmental outcomes of MeHg are well understood, but molecular understanding of teratogenic effects is rather limited. We performed here a genome - wide transcriptional analyses of 6, 30 and 50 μg/L MeHg treated zebrafish embryos from 4 to 72 h post-fertilization (hpf) using RNA-sequencing and self-printed microarray, and conducted a systematical comparison of MeHg - induced transcriptomic responses observed in this and our previous studies. We found that genes linked to gene ontology in terms of oxidative stress, visual, photoreception and cilium, and GABAergic synapse were enriched in embryo exposed from 4 to 72 hpf. The significantly altered genes involved in MAP kinase, TGF beta signaling pathway, oxidative phosphorylation, and glutathione metabolism were enriched across different exposure scenarios. We obtain 22 genes significantly regulated by MeHg, particularly the significant changes were determined in embryos exposed to 6 μg/L MeHg, which did not cause obviously teratogenic effects. Our findings show that the genes whose expression is altered by MeHg in embryonic stages may play important roles in adverse developmental endpoints and might be served as signatures for teratogenic effects.
Project description:The aim of reprotoxicity testing is to reveal adverse effects of chemicals and drugs on reproduction and on pre and postnatal fetal development. There is very limited data available on gene expression profiling for elucidation of the teratogenic effects of nongenotoxic teratogens. Therefore, research was undertaken to obtain knowledge on the molecular effects of MSC1096199 (previously known as EMD 82571), a calcium sensitizer that was abandoned in the preclinical development phase due to its teratogenic effects in some foetuses. Pregnant wistar rats were dose daily with either MSC1096199 (50 or 150 mg/kg) or Retinoic acid (10 mg/kg) on gestational days 6-17. Microarray experiment were performed using four different tissues (maternal liver, embryo liver (GD20), embryo bone (GD20), and whole embryo (GD12)) under four different conditions (vehicle, low dose and high dose of MSC1096199 and Retinoic acid) to determine the drug regulated genes. In the high dose treatment group, approximately 58% of the fetuses showed malformations i.e. exencephaly and agnathia, and toxicogenomics evidenced that the genes critically involved in osteogenesis, odontogenesis and extra cellular matrix components to be significantly regulated by MSC1096199, therefore providing a molecular rational for the observed teratogenic effects. Two-condition experiment, RA vs EMD 82571. Biological replicates:5 control, 5 treated. RNA from control and treatment groups were labeled with Cy3 and Cy5 fluorochromes, respectively. Cy3-channel pictures and correspondig raw data files are marked as 1b. Cy5-channel pictures and correspondig raw data files are marked as 2b.
Project description:The objectives of this study were to identify biomarkers for teratogenic response in a dose and time resolved manner and align the findings with morphological alterations found ZET assay. For this purpose triadimefon was selected as a model compound with teratogenic effects and known mode of action.
Project description:Purpose: Fetal alcohol spectrum disorders (FASD) result from ethanol exposure to the developing fetus. FASD occur in up to 1-5% of live births in the United States and there currently is no cure. Ethanol exposure to the developing central nervous system (CNS) has profound effects on learning and memory, impulse control, and motor function, resulting from neuropathology. The purpose of the current study was to perform transcriptome analysis to evaluate the effects of early postnatal ethanol exposure in the hippocampus and cerebellum. Methods: Postnatal C57BL/6 mice were treated with 4g/kg of ethanol from P4-P9, brains were harvested 24h after the final treatment at P10, hippocampi and cerebella were microdissected, RNA was isolated, and RNASeq analysis was performed. We compared differences in gene expression, sex-dependent expression, and global biological pathways associated with disruptions in hippocampal and cerebellar genes between the ethanol and vehicle treated neonates. Results: Ethanol caused both an up and down regulation of genes associated with the hippocampus and cerebellum, which may result in the disruption of normal circuitry and maturation and growth in these brain regions. Ethanol increased the expression of genes associated with the S phase of the cell cycle in both the hippocampus and cerebellum. In the cerebellum, ethanol increased effector gene expression, and in the hippocampus, genes associated with different interneuron lineages were altered. Postnatal ethanol exposure also resulted in altered expression of genes associated with oligodendrocyte lineages and myelination, along with alterations in microglia associated genes. Conclusion: Collectively, these data indicate that ethanol has profound effects on the hippocampus and cerebellum, resulting in alterations of gene expression and biological pathways regulating neurodevelopment. These studies may have important implications concerning alcohol-induced neuropathology and the neurological effects seen across the life span in FASD.