Project description:Prenatal exposure to synthetic corticosteroids can significantly alter postnatal development through changes in neurotransmitters and their receptors, and thus having long-lasting behavioral effects. Some of these changes have been observed in animal experiments, others also in humans prenatally exposed to synthetic corticosteroids. Here, we focused on transcriptomic changes within the prefrontal cortex of female rats prenatally exposed to either betamethasone or saline. The transcriptome has been assessed by novel computational tools to determine complex changes that may have life-long effects on phenotype, i.e., behavior. We analyzed how composition, topology and modulatory networks of the genomic fabric of the dopaminergic, GABAergic, and glutamatergic synapse (the transcriptome of the most interconnected and stably expressed gene network responsible for specific transmission) are afected by the prenatal exposure to corticosteroids and postnatal ketamine-induced seizures. One sex (F) x two prenatal exposures (B = betamethasone, S = saline) x two postnatal treatments (K = ketamine, S = saline). Biological replicates: 4 FSS, 4 FBS, 4 FBK.
Project description:Prenatal exposure to synthetic corticosteroids can significantly alter postnatal development through changes in neurotransmitters and their receptors, and thus having long-lasting behavioral effects. Some of these changes have been observed in animal experiments, others also in humans prenatally exposed to synthetic corticosteroids. Here, we focused on transcriptomic changes within the prefrontal cortex of female rats prenatally exposed to either betamethasone or saline. The transcriptome has been assessed by novel computational tools to determine complex changes that may have life-long effects on phenotype, i.e., behavior. We analyzed how composition, topology and modulatory networks of the genomic fabric of the dopaminergic, GABAergic, and glutamatergic synapse (the transcriptome of the most interconnected and stably expressed gene network responsible for specific transmission) are affected by prenatal exposure to corticosteroids and postnatal ketamine/saline treated NMDA-induced seizures.
Project description:Prenatal exposure to synthetic corticosteroids can significantly alter postnatal development through changes in neurotransmitters, peptides and their receptors, and thus having long-lasting behavioral effects. Some of these changes have been observed in animal experiments, others also in humans prenatally exposed to synthetic corticosteroids. Here, we focused on transcriptomic changes within the ARC of rats prenatally exposed to either betamethasone or saline. The expression of transcriptome has been assessed by novel computational tools to determine complex changes that may have life-long effects on phenotype, i.e., behavior. Total of 18,094 unigenes were quantified in the hypothalamic ARC of P14 male and female rats prenatally exposed to betametasone used in this experiment. Out of these genes, Kyoto Encyclopedia for Genes and Genomes (http://www.genome.jp) selected 112 for the dopaminergic synapse, 75 for the GABAergic and 97 for the glutamatergic synapse. We further analyzed composition, topology and modulatory networks of the genomic fabric of the dopaminergic, GABAergic, and glutamatergic synapse (the transcriptome of the most interconnected and stably expressed gene network responsible for specific transmission). Finally we investigated the M-bM-^@M-^\transcriptomic landscapeM-bM-^@M-^] of the GSF in the ARC of P14 males (M) and females (F) prenatally (G15) exposed to betamethasone (B) or saline (S). We combined in one measure (PWR = Pair-Wise Relevance) expression levels, controls and coordination of all pairs that can be formed by synapse genes with the other synapse genes, higher PWRs indicating larger influence of that gene pair to the fabric modulation. We found that prenatal exposure to betamethasone caused sex-dependent changes in the dopaminergic/GABA/glutamatergic synapse genes:. In males, 10 dopaminergic (9%), 4 GABAergic (5%) and 5 glutamatergic synapse genes (5%) were down-regulated. While in females, 9 dopaminergic (8%), 3 GABAergic (4%) and 6 glutamatergic (6%) synapse genes were downregulated. The data indicate that in both sexes the dopaminergic synapse was the most affected. In contrast, in control animals, no significant differences between male and female were present in these synapse genes. Since the most noticeable transcritpomic changes were found in the transcriptome of DA glutamatergic synapse, we investigated the expression of tyrosine-hydroxylase (TH) NMDA receptor subunits in the ARC. The western blot analyses and immunohistochemistry confirmed the sex-specific differences between prenatally betamethasone-exposed and saline-exposed P15 rats. Accordingly to the changes in gene expression, prenatal exposure to synthetic corticosteroids was associated with postnatal changes in behavior and susceptibility to certain types of seizures. While we did not find any significant impairements in normal behavioral patterns (open field activity), there was a sex-specific change in the novel object recognition test. We found that behavioral lateralization in females is lost after prenatal betamethasone exposure and both male and female prenatally betamethasone exposed rats were avoiding novelty. This trait is similar to children with autism and suggests that certain elements of autistic behaviors can be present after prenatal exposure to synthetic corticosteroids. Additionally, there were changes in the search patterns in the Morris water maze as well as in the Barnes maze. In conclusion, our work is consistent with findings of profound reprogramming changes in the brain after prenatal corticosteroid exposure associated with alterations cognitive functions and seizure susceptibility. Two-sexes (M, F) x two-condition (B = betamethasone prenataly exposed vs S = saline prenataly exposed) experiment. Biological replicates: 4 MS, 4 FS, 4 MB, 4 FB.
Project description:Prenatal exposure to synthetic corticosteroids can significantly alter postnatal development through changes in neurotransmitters, peptides and their receptors, and thus having long-lasting behavioral effects. Some of these changes have been observed in animal experiments, others also in humans prenatally exposed to synthetic corticosteroids. Here, we focused on transcriptomic changes within the ARC of rats prenatally exposed to either betamethasone or saline. The expression of transcriptome has been assessed by novel computational tools to determine complex changes that may have life-long effects on phenotype, i.e., behavior. Total of 18,094 unigenes were quantified in the hypothalamic ARC of P14 male and female rats prenatally exposed to betametasone used in this experiment. Out of these genes, Kyoto Encyclopedia for Genes and Genomes (http://www.genome.jp) selected 112 for the dopaminergic synapse, 75 for the GABAergic and 97 for the glutamatergic synapse. We further analyzed composition, topology and modulatory networks of the genomic fabric of the dopaminergic, GABAergic, and glutamatergic synapse (the transcriptome of the most interconnected and stably expressed gene network responsible for specific transmission). Finally we investigated the “transcriptomic landscape” of the GSF in the ARC of P14 males (M) and females (F) prenatally (G15) exposed to betamethasone (B) or saline (S). We combined in one measure (PWR = Pair-Wise Relevance) expression levels, controls and coordination of all pairs that can be formed by synapse genes with the other synapse genes, higher PWRs indicating larger influence of that gene pair to the fabric modulation. We found that prenatal exposure to betamethasone caused sex-dependent changes in the dopaminergic/GABA/glutamatergic synapse genes:. In males, 10 dopaminergic (9%), 4 GABAergic (5%) and 5 glutamatergic synapse genes (5%) were down-regulated. While in females, 9 dopaminergic (8%), 3 GABAergic (4%) and 6 glutamatergic (6%) synapse genes were downregulated. The data indicate that in both sexes the dopaminergic synapse was the most affected. In contrast, in control animals, no significant differences between male and female were present in these synapse genes. Since the most noticeable transcritpomic changes were found in the transcriptome of DA glutamatergic synapse, we investigated the expression of tyrosine-hydroxylase (TH) NMDA receptor subunits in the ARC. The western blot analyses and immunohistochemistry confirmed the sex-specific differences between prenatally betamethasone-exposed and saline-exposed P15 rats. Accordingly to the changes in gene expression, prenatal exposure to synthetic corticosteroids was associated with postnatal changes in behavior and susceptibility to certain types of seizures. While we did not find any significant impairements in normal behavioral patterns (open field activity), there was a sex-specific change in the novel object recognition test. We found that behavioral lateralization in females is lost after prenatal betamethasone exposure and both male and female prenatally betamethasone exposed rats were avoiding novelty. This trait is similar to children with autism and suggests that certain elements of autistic behaviors can be present after prenatal exposure to synthetic corticosteroids. Additionally, there were changes in the search patterns in the Morris water maze as well as in the Barnes maze. In conclusion, our work is consistent with findings of profound reprogramming changes in the brain after prenatal corticosteroid exposure associated with alterations cognitive functions and seizure susceptibility.
Project description:Oligodendrocytes undergo extensive changes as they differentiate from progenitors into myelinating cells. To better understand the; molecular mechanisms underlying this transformation, we performed a comparative analysis using gene expression profiling of A2B5+; oligodendrocyte progenitors and O4+ oligodendrocytes. Cells were sort-purified ex vivo from postnatal rat brain using flow cytometry. Using Affymetrix microarrays, 1707 transcripts were identified with a more than twofold increase in expression inO4+oligodendrocytes. Many genes required for oligodendrocyte differentiation were upregulated in O4+ oligodendrocytes, including numerous genes encoding; myelin proteins. Transcriptional changes included genes required for cell adhesion, actin cytoskeleton regulation, and fatty acid and; cholesterol biosynthesis. At the O4+ stage, there was an increase in expression of a novel proline-rich transmembrane protein (Prmp). Localized to the plasma membrane, Prmp displays adhesive properties that may be important for linking the extracellular matrix to the; actin cytoskeleton. Together, our results highlight the usefulness of this discovery-driven experimental strategy to identify genes relevant; to oligodendrocyte differentiation and myelination. Experiment Overall Design: Whole brain dissociates were prepared from one litter of 10 male postnatal day 7 rat pups for each of the 5 A2B5 bioligcal replicates and the 4 O4+ bioligical replicates. Total RNA was extracted from single A2B5+ and single O4+ cells sorted directly from postnatal day7 rat whole brain dissociates using flow cytometry.
Project description:The study determined whether there were gender differences in the <br>expression of hippocampal genes in adult rats in association with dissimilarity <br>in their behavior, and how these were affected by prenatal stress. Pregnant <br>Wistar rats were subjected to varied stress once daily on days 14-20 of <br>gestation.<br>