Project description:Prenatal alcohol exposure (PAE) is linked to elevated risk for systemic adult-onset diseases like hypertension, impaired glucose and immune regulation, and in animal models, to impaired recovery from acute onset diseases like cerebrovascular ischemic stroke. Recent evidence suggests that the gastrointestinal system rapidly becomes dysbiotic following cerebrovascular stroke, resulting in systemic inflammation. We hypothesized that a history of PAE would modify the systemic effects of stroke, and transduce exposure-dependent transcriptomic changes in downstream sentinel tissues of the enteric portal circulation that have previously been linked to biobehavioral outcomes in rodent PAE models. Pregnant Sprague Dawley rats were exposed to repeated episodes of vaporized ethanol or room air from gestational day 8 to 19. At 5 months, progeny from each treatment condition were subjected to unilateral endothelin-1 induced occlusion of the middle cerebral artery and outcomes evaluated after 2 days while other progeny stayed stroke-naïve. Stroke induced disabilities were assessed by behavioral assays (adhesive removal, Vibrissae evoked fore-limb placement, circling) and infarct size. The mesenteric adipose tissue and liver transcriptomes were assessed by sequencing, from age-matched stroke-exposed and stroke-naïve offspring. In stroke-naïve animals, pathway analysis identified rRNA processing as downregulated and citric acid cycle as upregulated in mesenteric adipose. Weighted gene correlation network analysis (WGCNA) identified, in the liver of stoke-naïve animals, a moderate but significant correlation between PAE status and necroptosis, a proinflammatory form of programmed cell death (Pearson’s r=0.554, p<0.05). Two days after a stroke, PAE rats exhibited worse neurological scores compared to controls (p<0.05). WGCNA after stroke identified an adipose gene network associated with B cell differentiation and NF-kappa B signaling as moderately correlated with post-stroke neurological function (Pearson's r=0.52, p=0.05). Post-stroke WGCNA also identified a liver proinflammatory gene network strongly correlated with post-stroke neurological function (Pearson's r=-0.63, p<0.01). PAE persistently alters the transcriptome of afferent tissue targets of enteric circulation in adult rat offspring. Moreover, PAE-linked enteric inflammation is correlated to worse outcomes following cerebrovascular ischemic stroke in adulthood. Enteric disturbances may mediate adverse brain health outcomes due to PAE in adulthood.

Project description:Fetal Alcohol Spectrum Disorder (FASD) encompasses an array of effects of prenatal alcohol exposure (PAE), including physical abnormalities and cognitive and behavioral deficits. Disruptions of cortical development have been implicated in multiple PAE studies, with deficits including decreased progenitor proliferation, disrupted neuronal differentiation, aberrant radial migration of pyramidal neurons, and decreased cortical thickness. While several mechanisms of alcohol teratogenicity have been explored, how specific cell types in the brain at different developmental time points may be differentially affected by PAE is still poorly understood. In this study, we used single nucleus RNA sequencing (snRNAseq) to investigate whether moderate PAE from neurulation through peak cortical neurogenesis induces cell type-specific transcriptomic changes in the developing murine brain. Cluster analysis identified 25 neuronal cell types, including subtypes of neural epithelial cells (NECs), radial glial cells (RGCs), intermediate progenitor cells (IPCs), projection neurons, and interneurons. Only Wnt-expressing NECs showed a significant decrease in the percentage of cells after PAE, with no cell types showing PAE-induced apoptosis as measured by caspase expression. Cell cycle analysis revealed only a subtype of RGCs expressing the downstream Wnt signaling transcription factor Tcf7l2 had a decreased percentage of cells in the G2/M phase of the cell cycle, suggesting decreased proliferation in this RGC subtype and further implicating disrupted Wnt signaling after PAE at this early developmental timepoint. An increased pseudotime score in IPC and projection neuron cell types indicated that PAE led to increased or premature differentiation of these cells. Biological processes affected by PAE included the upregulation of pathways related to synaptic activity and neuronal differentiation and downregulation of pathways related to chromosome structure and the cell cycle. Several cell types showed a decrease in Wnt signaling pathways, with several genes related to Wnt signaling altered by PAE in multiple cell types. As Wnt has been shown to promote proliferation and inhibit differentiation at earlier stages in development, the downregulation of Wnt signaling may have resulted in premature neuronal maturation of projection neurons and their intermediate progenitors. Overall, these findings provide further insight into the cell type-specific effects of PAE during early corticogenesis.

Project description:Background: Prenatal alcohol exposure (PAE) is associated with alterations in numerous physiological systems, including the stress and immune systems. We have previously shown that PAE increases the course and severity of arthritis in an adjuvant-induced arthritis (AA) model. While the molecular mechanisms underlying these effects are not fully known, changes in neural gene expression are emerging as important factors in the etiology of PAE effects. As the prefrontal cortex (PFC) and hippocampus (HPC) play key roles in neuroimmune function, PAE-induced alterations to their transcriptome may underlie abnormal steady-state functions and responses to immune challenge. The current study examined brains from adult PAE and control females from our recent AA study to determine whether PAE causes long-term alterations in gene expression and whether these mediate the altered severity and course of arthritis in PAE females Methods: Adult females from PAE, pair-fed [PF], and ad libitum-fed control [C]) groups were injected with either saline or complete FreundM-bM-^@M-^Ys adjuvant. Animals were terminated at the peak of inflammation or during resolution (days 16 and 39 post-injection, respectively); cohorts of saline-injected PAE, PF and C females were terminated in parallel. Gene expression was analyzed in the PFC and HPC using whole genome mRNA expression microarrays. Results: Significant changes in gene expression in both the PFC and HPC were found in PAE compared to controls in response to ethanol exposure alone (saline-injected females), including genes involved in neurodevelopment, apoptosis, and energy metabolism. Moreover, in response to inflammation (adjuvant-injected females), PAE animals showed unique expression patterns, while failing to exhibit the activation of genes and regulators involved in the immune response observed in control and pair-fed animals. Conclusions: These results support the hypothesis that PAE affects neuroimmune function at the level of gene expression, demonstrating long-term effects of PAE on the CNS response under steady-state conditions and following an inflammatory insult. Key words: prenatal alcohol exposure (PAE), ethanol, inflammation, arthritis, gene expression, rat. 192 samples, including 20 hybridization replicates

Project description:Staphylococcus aureus thymidine-dependent small-colony variants (TD-SCVs) are frequently isolated from patients with chronic S. aureus infections after long-term treatment with trimethoprim-sulfamethoxazole (TMP-SMX). In TD-SCVs, mutations of thymidylate synthase (thyA, TS), essential for DNA synthesis, occur. However, it has never been shown, that TMP-SMX is responsible for the induction and selection of TD-SCVs. Short-term exposure of TMP-SMX induced the TD-SCV phenotype morphologically as shown in transmission electron-microscopy and on the transcriptional level by qRT-PCR in wild-type S. aureus, while selection of TD-SCVs with thyA mutations occurred only rarely after long-term exposure. In reversion experiments with clinical TD-SCVs, all revertants revealed compensating mutations at the initially identified mutation site. Whole DNA microarray analysis of a thyA deletion mutant (M-bM-^HM-^FthyA), which exhibited the typical TD-SCV phenotype, identified tremendous alterations compared to the wild-type. Important virulence regulators such as agr, arlRS, sarA and major virulence determinants including hla, hlb, sspA, sspB and geh were down-regulated, while genes associated with the colonization capacity like fnbA, fnbB, spa, clfB, sdrC and sdrD were up-regulated. The expression of genes involved in pyrimidine and purine metabolism as well as in nucleotide interconversion changed significantly. The M-bM-^HM-^FthyA-mutant was attenuated in virulence in both, a Caenorhabditis elegans killing model and an acute murine pneumonia model. Furthermore, competition experiments in vitro and in vivo (using a chronic pneumonia mouse model) revealed a survival and growth advantage of the M-bM-^HM-^FthyA-mutant under low thymidine conditions and TMP-SMX exposure. In conclusion, our results clearly show for the first time that TMP-SMX induces the TD-SCV phenotype after short-term exposure in S. aureus and that long-term exposure selects thyA mutations providing an advantage for TD-SCVs under specified conditions. Thus, our results help to understand the dynamic processes of induction and selection of S. aureus TD-SCVs during TMP-SMX exposure. 18 independent samples were analysed; for each isolate and time point 3 replicates were performed

			Action	DRS
	SRR6998931_1.fastq.gz	Fastqsanger.gz
	SRR6998931_2.fastq.gz	Fastqsanger.gz

Dataset Information

Dataset's files

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets