The objective of this study was to compare the transcriptional repertoire of mature human neutrophils before and after GM-CSF treatment by using oligonucleotide microarrays.
RhoH/TTF negatively regulates leukotriene production in neutrophils.
Specimen part
View SamplesTotal RNA was prepared using TRIzol reagent from the pancreata of eight week old male mice. The genotypes were Control: gastrin+/-, CFTR+/+; and CF: gastrin+/-, CFTR-/-. All mice were on 95% black6, 5% 129Sv background. Mice were fed Peptamen from age 10 days to prevent intestinal obstruction.
Acidic duodenal pH alters gene expression in the cystic fibrosis mouse pancreas.
No sample metadata fields
View SamplesDysregulation of ceramide synthesis has been associated with metabolic disorders such as atherosclerosis and diabetes mellitus. Using a human hepatoma cell line (Huh7), we investigated the changes in lipid homeostasis and gene expression when the synthesis of ceramide is perturbed by knocking down serine transferases subunits 1, 2 and 3 (SPTLC123) or dihydroceramide desaturase (DEGS1). While the inhibition of serine palmitoyl transferase (SPTLC) affects ceramide production differently at the subspecies level depending upon which SPTLC subunit is silenced; depleting DEGS1 is sufficient to produce a similar outcome as knocking down all SPTLC subunits. Both the distribution of multiple lipid classes, especially at the subspecies level, and the global transcriptional profile is altered differently when either SPTLC123 or DEGS1 were silenced. The overall transcriptional changes indicate a negative regulation in biosynthetic processes and a down-regulation of genes involved in general endomembrane trafficking for both DEGS1 and SPTLC123 siRNA treated cells, but also the up-regulation of genes involved with cell migration function in DEGS1 siRNA cells. Pathway analysis indicate changes in amino acid, sugar and nucleotide metabolisms as well as vesicle trafficking between organelles occurred more robustly in DEGS1 silenced cells. Although either SPTLC123 or DEGS1 siRNA treatment positively regulated numerous genes involved with endocytosis and endosomal recycling, depleting SPTLC123 caused transcriptional changes in genes primarily involved with lipid metabolism. The alterations reflect how SPTLC or DEGS1 silenced cells respond differently to disruption in lipid flux, but also maintain cellular lipid pools through increasing endocytotic processes and down-regulating metabolic biosynthesis without developing endoplasmic reticulum stress. Also, these results are the first to demonstrate that reducing ceramide synthesis by decreasing the function of either SPTLC or DEGS1 affects cellular function differently at the level of lipid synthesis and gene expression.
Silencing of enzymes involved in ceramide biosynthesis causes distinct global alterations of lipid homeostasis and gene expression.
Cell line
View SamplesThis SuperSeries is composed of the SubSeries listed below.
HDAC inhibitors attenuate the development of hypersensitivity in models of neuropathic pain.
Specimen part
View SamplesHistone deacetylase inhibitors (HDACIs) interfere with the epigenetic process of histone acetylation and are known to have analgesic properties in models of chronic inflammatory pain. The aim of this study was to determine whether these compounds could also affect neuropathic pain. Different class I HDACIs were delivered intrathecally into rat spinal cord in models of traumatic nerve injury and antiretroviral drug-induced peripheral neuropathy (stavudine, d4T). Mechanical and thermal hypersensitivity was attenuated by 40% to 50% as a result of HDACI treatment, but only if started before any insult. The drugs globally increased histone acetylation in the spinal cord, but appeared to have no measurable effects in relevant dorsal root ganglia in this treatment paradigm, suggesting that any potential mechanism should be sought in the central nervous system. Microarray analysis of dorsal cord RNA revealed the signature of the specific compound used (MS-275) and suggested that its main effect was mediated through HDAC1. Taken together, these data support a role for histone acetylation in the emergence of neuropathic pain.
HDAC inhibitors attenuate the development of hypersensitivity in models of neuropathic pain.
Specimen part
View SamplesHistone deacetylase inhibitors (HDACIs) interfere with the epigenetic process of histone acetylation and are known to have analgesic properties in models of chronic inflammatory pain. The aim of this study was to determine whether these compounds could also affect neuropathic pain. Different class I HDACIs were delivered intrathecally into rat spinal cord in models of traumatic nerve injury and antiretroviral drug-induced peripheral neuropathy (stavudine, d4T). Mechanical and thermal hypersensitivity was attenuated by 40% to 50% as a result of HDACI treatment, but only if started before any insult. The drugs globally increased histone acetylation in the spinal cord, but appeared to have no measurable effects in relevant dorsal root ganglia in this treatment paradigm, suggesting that any potential mechanism should be sought in the central nervous system. Microarray analysis of dorsal cord RNA revealed the signature of the specific compound used (MS-275) and suggested that its main effect was mediated through HDAC1. Taken together, these data support a role for histone acetylation in the emergence of neuropathic pain.
HDAC inhibitors attenuate the development of hypersensitivity in models of neuropathic pain.
Specimen part
View SamplesWhile histone deacetylase (HDAC) inhibitors are thought to regulate gene expression by post-translational modification of histone as well as non-histone proteins. While histone hyperacetylation has long been considered the paradigmatic mechanism of action, recent genome-wide profiles indicate more complex interactions with the epigenome. In particular, HDAC inhibitors also induce histone deacetylation at the promoters of highly active genes, resulting in gene suppression. This was linked to the loss of histone acetyltransferase (HAT) binding. To illustrate pre-clinical utility of the HDAC inhibitor SAHA as a therapeutic, we show reversal of diabetes-associated EP300 target genes in diabetic HAECs of primary origin. These results were confirmed using SAHA, C646 (EP300/CREBBP inhibitor) or EP300 siRNA. These findings suggest the inhibition of gene expression by SAHA is mediated by EP300 function and provide a rationale for clinical trials of safety and efficacy in patients with diabetes. Overall design: Human aortic endothelial cells from a diabetic and non-diabetic individual were stimulated with DMSO (control), SAHA (2 µM, HDAC inhibitor) or C646 (10 µM, EP300 inhibitor) for 12 hours, or EP300 siRNA or non-target siRNA (control) for 4 hours, followed by 48 hours in fresh media. Study performed in triplicate.
Systems approach to the pharmacological actions of HDAC inhibitors reveals EP300 activities and convergent mechanisms of regulation in diabetes.
No sample metadata fields
View SamplesMethyl-dependent regulation of transcription has expanded from a traditional focus on histones to encompass transcription factor modulation. While the Set7 lysine methyltransferase is associated with pro-inflammatory gene expression in vascular endothelial cells, genome-wide regulatory roles remain to be investigated. From initial characterization of Set7 as specific for methyl-lysine 4 of H3 histones (H3K4m1), biochemical activity toward non-histone substrates has revealed additional mechanisms of gene regulation. mRNA-Seq revealed transcriptional deregulation of over 8,000 genes in an endothelial model of Set7 knockdown. Gene ontology identified up-regulated pathways involved in developmental processes and extracellular matrix remodeling, whereas pathways regulating the inflammatory response as well as nitric oxide signaling were down-regulated. Chromatin maps derived from ChIP-Seq profiling of H3K4m1 identified several hundred loci with loss of H3K4m1 at gene regulatory elements associated with an unexpectedly subtle effect on gene expression. Transcription factor network analysis implicated six previously described Set7 substrates in mRNA-Seq changes, and we predict that Set7 post-translationally regulates other transcription factors associated with vascular endothelial gene expression through the presence of Set7 amino acid methylation motifs. We describe a role for Set7 in regulating developmental pathways and response to stimuli (inflammation/immune response) in human endothelial cells of vascular origin. Set7-dependent gene expression changes that occurred independent of H3K4m1 may involve transcription factor lysine methylation events. The method of mapping measured transcriptional changes to transcription factors to identify putative substrates with strong associations to functional changes is applicable to substrate prediction for other broad-substrate histone modifiers. Overall design: We used lentiviral delivered shRNA to knock down the expression of Set7 protein in HMEC-1 cells. As a control, we used a non-targeting shRNA. RNA-seq was performed in biological triplicate. Set7 knock down datasets are labeled “Set7KD” and non-targeting control datasets are labeled “NTC”
Deep sequencing reveals novel Set7 networks.
Cell line, Subject
View SamplesMaternal obesity can program metabolic syndrome in offspring but the mechanisms are not well characterized. Moreover, the consequences of maternal overnutrition in the absence of frank obesity remain poorly understood. This study aimed to determine the effects of maternal consumption of a high fat-sucrose diet on the skeletal muscle metabolic and transcriptional profiles of adult offspring. Female Sprague Dawley rats were fed either a diet rich in saturated fat and sucrose (HFD, 23.5% fat, 20% sucrose wt/wt) or a standard chow diet (NFD, 7% fat, 10% sucrose w/w) for the 3 weeks prior to mating and throughout pregnancy and lactation. Although maternal weights were not different between groups at conception or weaning, HFD dams were ~22% heavier than chow fed dams from mid-pregnancy until 4 days post-partum. Adult male offspring of HFD dams were not heavier than controls but demonstrated features of insulin resistance including elevated plasma insulin concentration (+40%, P<0.05). Next Generation mRNA Sequencing was used to identify differentially expressed genes in the soleus muscle of offspring, and Gene Set Enrichment Analysis (GSEA) to detect coordinated changes that are characteristic of a biological function. GSEA identified 15 pathways enriched for up-regulated genes, including cytokine signaling (P<0.005), starch and sucrose metabolism (P<0.017), and inflammatory response (P<0.024). A further 8 pathways were significantly enriched for down-regulated genes including oxidative phosphorylation (P<0.004) and electron transport (P<0.022). Western blots confirmed a ~60% reduction in the phosphorylation of the insulin signaling protein Akt (P<0.05) and ~70% reduction in mitochondrial complexes II (P<0.05) and V expression (P<0.05). On a normal diet, offspring of HFD dams developed an insulin resistant phenotype, with transcriptional evidence of muscle cytokine activation, inflammation and mitochondrial dysfunction. These data indicate that maternal overnutrition, even in the absence of pre-pregnancy obesity can promote metabolic dysregulation and predispose offspring to type 2 diabetes. Overall design: Messenger RNA profile of skeletal muscle of male offspring from female Sprague Dawley rats fed either a diet rich in saturated fat and sucrose (HFD, 23.5% fat, 20% sucrose wt/wt) or a standard chow diet (NFD, 7% fat, 10% sucrose w/w) for the 3 weeks prior to mating and throughout pregnancy and lactation. There were 5 HFD samples compared to 6 NFD control samples.
Maternal overnutrition programs changes in the expression of skeletal muscle genes that are associated with insulin resistance and defects of oxidative phosphorylation in adult male rat offspring.
No sample metadata fields
View SamplesThis SuperSeries is composed of the SubSeries listed below.
miR-155 in the progression of lung fibrosis in systemic sclerosis.
Specimen part, Disease
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