Sirtuin 3 (SIRT3) is an NAD+-dependent deacetylase downregulated in aging and age-associated diseases such as cancer and neurodegeneration, and high fat diet (HFD)-induced metabolic disorders. Thus, we performed a small molecule screen and identified an unexpected metabolic vulnerability associated with SIRT3 loss. Overall design: RNA sequencing in SV40T immortalized SIRT3 WT (triplicates) and SIRT3 KO MEF (duplicates) lines under normal conditions.
Small-Molecule Screen Identifies De Novo Nucleotide Synthesis as a Vulnerability of Cells Lacking SIRT3.
Specimen part, Cell line, Subject
View SamplesBiotin is cofactor of crucial enzymes for intermediary metabolism, and its deficiency affects the transcription of some critical genes of mammalian glucose metabolism. However, the precise mechanisms of biotin starvation on gene expression are unknown. Here we show that metabolic changes ushered by deficiency of this vitamin sets in motion extensive reorganization of carbon metabolism gene expression, consistent across three diverse eukaryotes, that is mediated through a regulatory circuitry at the genome level similar in the three species.
Biotin starvation with adequate glucose provision causes paradoxical changes in fuel metabolism gene expression similar in rat (Rattus norvegicus), nematode (Caenorhabditis elegans) and yeast (Saccharomyces cerevisiae).
Age, Specimen part
View SamplesCumulus-oocyte complexes were isolated a seperate time-points to generate temporal complexes. Targets from two biological replicates at each time point (0h, 8h, 16h post-hCG treatment) were generated and the expression profiles were determined using Affymetrix GeneChip Mouse Genome 430 2.0 Arrays. Comparisons between the sample groups allow the identification of genes with temporal expression patterns.
Gene expression profiles of cumulus cell oocyte complexes during ovulation reveal cumulus cells express neuronal and immune-related genes: does this expand their role in the ovulation process?
No sample metadata fields
View SamplesThe forkhead box transcription factor FOXO1 is highly expressed in granulosa cells of growing follicles but is down-regulated by FSH in culture or by LH-induced luteinization in vivo. To analyze the function of FOXO1, we infected rat and mouse granulosa cells with adenoviral vectors expressing two FOXO1 mutants: a gain-of-function mutant FOXOA3 that has two serine residues and one threonine residue mutated to alanines rendering this protein constitutively active and nuclear, and a FOXOA3-mutant DNA-binding domain (mDBD) in which the DBD is mutated. The infected cells were then treated with vehicle or FSH for specific time intervals. Infection of the granulosa cells was highly efficient, caused only minimal apoptosis, and maintained FOXO1 protein at levels of the endogenous protein observed in cells before exposure to FSH. RNA was prepared from control and adenoviral infected cells exposed to vehicle or FSH for 12 and 24 h. Affymetrix microarray and database analyses identified, and real time RT-PCR verified, that genes within the lipid, sterol, and steroidogenic biosynthetic pathways (Hmgcs1, Hmgcr, Mvk, Sqle, Lss, Cyp51, Tm7sf2, Dhcr24 and Star, Cyp11a1, and Cyp19), including two key transcriptional regulators Srebf1 and Srebf2 of cholesterol biosynthesis and steroidogenesis (Nr5a1, Nr5a2), were major targets induced by FSH and suppressed by FOXOA3 and FOXOA3-mDBD in the cultured granulosa cells. By contrast, FOXOA3 and FOXOA3- mDBD induced expression of Cyp27a1 mRNA that encodes an enzyme involved in cholesterol catabolism to oxysterols. The genes up-regulated by FSH in cultured granulosa cells were also induced in granulosa cells of preovulatory follicles and corpora lutea collected from immature mice primed with FSH (equine choriogonadotropin) and LH (human choriogonadotropin), respectively. Conversely, Foxo1 and Cyp27a1 mRNAs were reduced by these same treatments. Collectively, these data provide novel evidence that FOXO1 may play a key role in granulosa cells to modulate lipid and sterol biosynthesis, thereby preventing elevated steroidogenesis during early stages of follicle development.
FSH and FOXO1 regulate genes in the sterol/steroid and lipid biosynthetic pathways in granulosa cells.
Sex
View SamplesBackground: Gliomas are the most common type of primary brain tumours, and in this group glioblastomas (GBMs) are the higher-grade gliomas with fast progression and unfortunate prognosis. Two major aspects of glioma biology that contributes to its awful prognosis are the formation of new blood vessels through the process of angiogenesis and the invasion of glioma cells. Despite of advances, two-year survival for GBM patients with optimal therapy is less than 30%. Even in those patients with low-grade gliomas, that imply a moderately good prognosis, treatment is almost never curative. Recent studies have demonstrated the existence of a small fraction of glioma cells with characteristics of neural stem cells which are able to grow in vitro forming neurospheres and that can be isolated in vivo using surface markers such as CD133. The aim of this study was to define the molecular signature of GBM cells expressing CD133 in comparison with non expressing CD133 cells. This molecular classification could lead to the finding of new potential therapeutic targets for the rationale treatment of high grade GBM.
Molecular analysis of ex-vivo CD133+ GBM cells revealed a common invasive and angiogenic profile but different proliferative signatures among high grade gliomas.
Specimen part, Disease
View SamplesCytokine genes are targets of multiple epigenetic mechanisms in T lymphocytes. 5-azacytidine (5-azaC) is a nucleoside-based DNA methyltransferases (DNMT) inhibitor which induces demethylation and gene reactivation. In the current study, we analyzed the effect of 5-azaC in T-cell function and observed that 5-azaC inhibits T-cell proliferation and activation, blocking cell cycle in G0-G1 phase and decreasing the production of proinflammatory cytokines such as TNF and IFN. This effect was not due to a pro-apoptotic effect of the drug but to the down-regulation of genes involved in T-cell cycle progression and activation such as CCNG2, MTCP1, CD58, and ADK and up-regulation of genes which induce cell growth arrest, such as DCUN1D2, U2AF2, GADD45B or p53. In spite of being also up-regulated, we did not find any effect of 5-azaC on the methylation pattern of FOXP3. Finally, the administration of 5-azaC at 60 and 84 hours post-transplant prevented the development of GVHD leading to a significant increase in survival in a fully mismatched BMT mouse model. In conclusion, the current study shows the effect of 5-azaC in T-lymphocytes and illustrates its role in the allogeneic transplantation setting as an immunomodulatory drug, describing new pathways which must be explored in order to prevent graft-versus-host disease.
Immunomodulatory effect of 5-azacytidine (5-azaC): potential role in the transplantation setting.
Specimen part, Treatment, Time
View SamplesA number of macrophage and macrophage-like cells are responsible for immune response to challenges. Despite their shared role, these immune cells differ in the inflammatory response and impact on physiology and behavior. The purpose of this study was to profile mRNA levels (transcriptome) to better understand differences between immune cells under homeostasis using two mouse strains. Overall design: total RNA samples were obtained from 12 mice per strain and immune cell type and were subjected to paired-end RNA sequencing
Microglia Transcriptome Changes in a Model of Depressive Behavior after Immune Challenge.
No sample metadata fields
View SamplesAtrial fibrillation (AF) is a major risk factor for cardioembolic stroke. Anticoagulant drugs are effective in preventing AF-related stroke. However, the high frequency of anticoagulant-associated major bleeding is a major concern particularly when antiplatelet treatment is simultaneously administered. Here, microarray analysis in peripheral blood cells in eight patients with AF and stroke and eight AF subjects without stroke identified a stroke related gene expression pattern. HSPA1B, which encodes for heat-shock protein 70 kDa (Hsp70), was the most differentially expressed gene. This gene was downregulated in stroke subjects, a finding confirmed further in an independent AF cohort of 200 individuals. Hsp70 knock-out (KO) mice subjected to different thrombotic challenges developed thrombosis significantly earlier than their wild-type (WT) counterparts.
Hsp70 protects from stroke in atrial fibrillation patients by preventing thrombosis without increased bleeding risk.
Specimen part
View SamplesIFN alpha mediated gene expression pattern. The effect of IFN alpha on human CD8 T cells responding to antigen (signal 1) and costimulatory signals (signal 2) provided by beads coated with anti-CD3 and anti-CD28 mAbs.
Effects of IFN-α as a signal-3 cytokine on human naïve and antigen-experienced CD8(+) T cells.
Specimen part, Subject, Time
View SamplesGene expression profile of acute myeloid leukemia.
Gene expression profile reveals deregulation of genes with relevant functions in the different subclasses of acute myeloid leukemia.
No sample metadata fields
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