Project description:To study the relationship between microRNAs and μ-opioid receptor (MOR) signaling, we examined microRNA expression after chronic morphine or fentanyl treatment in rat primary hippocampal neurons and in mouse hippocampus. Mouse cerebellum region was also tested as a negative control to eliminate microRNA expression changes unrelated to MOR signaling, as the cerebellum is essentially devoid of MOR. We identified a number of microRNAs that altered their expression upon treatment with both morphine and fentanyl in the rat and mouse systems. There were, however, some microRNAs that changed in response to morphine, or fentanyl, but not both. Keywords: Expression profiling
Project description:Soman (O-Pinacolyl methylphosphonofluoridate) is a potent neurotoxicant. Acute exposure to soman causes profound inhibition of the critical enzyme acetylcholinesterase, resulting in excessive levels of the neurotransmitter acetylcholine. Excessive acetylcholine levels cause convulsions, seizures, and respiratory distress. The initial cholinergic crisis can be overcome by rapid anti-cholinergic therapeutic intervention, resulting in increased survival. However, conventional treatments do not protect the brain from seizure-related damage, and thus neurodegeneration of soman-sensitive areas of the brain is a potential post-exposure outcome. We performed gene expression profiling of rat hippocampus following soman exposure to gain greater insight into the molecular pathogenesis of soman-induced neurodegeneration. Keywords: Time-course; toxicant exposure
Project description:To study the relationship between microRNAs and μ-opioid receptor (MOR) signaling, we examined microRNA expression after chronic morphine or fentanyl treatment in rat primary hippocampal neurons and in mouse hippocampus. Mouse cerebellum region was also tested as a negative control to eliminate microRNA expression changes unrelated to MOR signaling, as the cerebellum is essentially devoid of MOR. We identified a number of microRNAs that altered their expression upon treatment with both morphine and fentanyl in the rat and mouse systems. There were, however, some microRNAs that changed in response to morphine, or fentanyl, but not both. Keywords: Expression profiling There are up to three biological replicates (indicated by 1, 2, and 3) of primary hippocampal neurons from new born rats and the cerebellum and hippocampus regions from adult mice treated for three days (control, morphine, and fentanyl). The biological replicates were from experiments performed on different dates. Each biological replicate contained cells or tissues collected from multiple animals so that enough RNA could be extracted for RNA analysis. RNA was labelled with a green dye, mixed with a reference DNA sample labelled with a red dye. The reference DNA contained a number of synthetic DNA oligos with mature microRNA sequences that served to verify microarray hybridization. RNA signals were in ch1, DNA signals ch2.
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.
Project description:DNA methylation dynamics influence brain function and are altered in neurological disorders. 5-hydroxymethylcytosine (5-hmC), a DNA base derived from 5-methylcytosine (5mC) accounts for ~40% of modified cytosine in brain, and has been implicated in DNA methylation-related plasticity. Here we map 5-hmC genome-wide across three ages in mouse hippocampus and cerebellum, allowing assessment of its stability and dynamic regulation during postnatal neurodevelopment through adulthood. We find developmentally programmed acquisition of 5-hmC in neuronal cells. Epigenomic localization of 5-hmC-regulated regions reveals stable and dynamically modified loci during neurodevelopment and aging. By profiling 5-hmC in human cerebellum we establish conserved genomic features of 5-hmC. Finally, we implicate 5-hmC in neurodevelopmental disease by finding that its levels are inversely correlated with methyl-CpG-binding protein 2 (Mecp2) dosage, a protein encoded by a gene in which mutations cause Rett Syndrome. These data point toward critical roles for 5-hmC-mediated epigenetic modification in neurodevelopment and diseases. Here we map 5-hmC genome-wide across three ages in mouse hippocampus and cerebellum, allowing assessment of its stability and dynamic regulation during postnatal neurodevelopment through adulthood. Profiling of 5-hmC in human cerebellum we establish conserved genomic features of 5-hmC. Finally, we implicate 5-hmC in neurodevelopmental disease by profiling 5-hmC in mouse cerebellum lacking MeCP2, a protein encoded by a gene in which mutations cause Rett Syndrome.