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GSE19620
Homo sapiens
2 Downloadable Samples
Illumina HumanWG-6 v3.0 expression beadchip
Description
Skeletal muscle of insulin resistant individuals is characterized by lower fasting lipid oxidation and reduced ability to switch between lipid and glucose oxidation. The purpose of the present study was to examine if impaired metabolic switching could be induced by chronic hyperglycemia. Human myotubes were treated with or without chronic hyperglycemia (HG) (20 mmol/l glucose for 4 days), and the metabolism of [14C]oleic acid (OA) and [14C]glucose was studied. Acute glucose (5mmol/l) suppressed OA oxidation by 50% in normoglycemic (NG) (5.5 mmol/l glucose) cells. Myotubes exposed to chronic hyperglycemia showed a significantly reduced OA uptake and oxidation to CO2, whereas acid-soluble metabolites were increased. Glucose suppressibility, the ability of acute glucose to suppress lipid oxidation, was significantly reduced to 21%, while adaptability, the capacity to increase lipid oxidation with increasing fatty acid availability, was unaffected. Glucose uptake and oxidation was significantly reduced by about 40%. Substrate oxidation in presence of mitochondrial uncouplers showed that net and maximal oxidative capacities were significantly reduced after hyperglycemia, and the concentration of ATP was reduced by 25%. However, none of the measured mitochondrial genes were downregulated nor was mitochondrial content. Microarray showed that no genes were significantly regulated by chronic hyperglycemia. Addition of chronic lactate reduced both glucose and OA oxidation to the same extent as hyperglycemia, and this effect was specific for lactate. In conclusions, chronic hyperglycemia reduced substrate oxidation in skeletal muscle cells and impaired the metabolic switching. The effect is most likely due to an induced mitochondrial dysfunction.
Publication Title
Chronic hyperglycemia reduces substrate oxidation and impairs metabolic switching of human myotubes.
Sample Metadata Fields
Specimen part
View Samples- Rattus norvegicus
- 11 Downloadable Samples
- Affymetrix Rat Expression 230A Array (rae230a)
Description
E2F1 has been shown to induce both proliferation and apoptosis.
Publication Title
An E2F1-dependent gene expression program that determines the balance between proliferation and cell death.
Sample Metadata Fields
No sample metadata fields
View Samples- Mus musculus
- 23 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
Gene expression profiling with microarrays was used to identify genes differentially expressed in the lungs of B6 and BALB CF mice compared to non-CF littermates
Publication Title
Strain-dependent pulmonary gene expression profiles of a cystic fibrosis mouse model.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 4 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Infection with Chlamydia pneumoniae, a human respiratory pathogen, has been associated with various chronic diseases such as asthma, coronary heart disease and importantly atherosclerosis. Possibly because the pathogen can exist in a persistent form. TNF-a has been reported to induce chlamydial persitence in epithelial cell lines, however the mechanism of TNF-a-induced persistence has not been reported. Moreover, C. pneumoniae persistently infect human dendritic cells (DCs) and activate DCs to produce cytokines including TNF-a. Induction of chlamydial persistence by other cytokines such as IFN-g is known to be due to indoleamine 2,3-dioxygenase (IDO) activity. The present study therefore, investigated whether C. pneumoniae infection can induce IDO activity in dendritic cells, and whether the restriction of chlamydial growth in the DCs by TNF-a is IDO-dependent. Our data indicate that infection of DCs with C. pneumoniae resulted in the induction of IDO expression. Reporting on our use of anti-TNF-a antibody adalimumab and varying concentrations of TNF-a, we further demonstrate that IDO induction following infection of DCs with C. pneumoniae is TNF-a-dependent. The anti-chlamydial activity induced by TNF-a and the expression of chlamydial 16S rRNA gene, euo, groEL1, ftsk and tal genes was correlated with the induction of IDO. Addition of excess amounts of tryptophan to the DC cultures resulted in abrogation of the TNF-a-mediated chlamydial growth restriction. These findings suggest that infection of DCs by C. pneumoniae induces production of functional IDO, which subsequently causes depletion of tryptophan. This may represent a potential mechanism for DCs to restrict bacterial growth in chlamydial infections.
Publication Title
Restriction of Chlamydia pneumoniae replication in human dendritic cell by activation of indoleamine 2,3-dioxygenase.
Sample Metadata Fields
Specimen part
View Samples- Homo sapiens
- 20 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
This SuperSeries is composed of the SubSeries listed below.
Publication Title
Definition of the landscape of promoter DNA hypomethylation in liver cancer.
Sample Metadata Fields
Specimen part, Cell line, Subject
View Samples- Homo sapiens
- 20 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Extensive loss of DNA methylation is a hallmark of cancer. The role of hypomethylation in altering gene expression in cancer cells has been poorly understood. Hepatic cellular carcinoma (HCC) is one of the most common human cancers. We use HCC as a model to investigate hypomethylation in cancer by a combination of methylated DNA immunoprecipitation and hybridization with comprehensive promoter arrays. We identify approximately 2,800 promoters that are hypomethylated in tumor samples. The hypomethylated promoters appear in clusters across the genome suggesting a high-level organization behind the epigenomic changes in cancer. The genes whose promoters are demethylated are mainly involved in cell growth, cell adhesion and communication, signal transduction, mobility and invasion; functions that are essential for cancer progression and metastasis. Previous studies suggested that MBD2 was involved in demethylation of uPA and MMP2 genes in human breast and prostate cancer cell lines. We extend these results here showing that whereas MBD2 depletion in normal liver cells has little or no effect, its depletion in the human hepatocellular carcinoma cell line HepG2 and the adenocarcinoma cell line SkHep1 results in suppression of cell growth, anchorage-independent growth and invasiveness, as well as an increase in promoter methylation and silencing of several of the genes that are hypomethylated in tumors. Our studies establish for the first time the rules governing hypomethylation of promoters in liver cancer and define the potential functional role of hypomethylation in cancer.
Publication Title
Definition of the landscape of promoter DNA hypomethylation in liver cancer.
Sample Metadata Fields
Specimen part, Subject
View Samples- Mus musculus
- 24 Downloadable Samples
- Affymetrix Mouse Clariom S Array (clariomsmouse)
Description
The intestinal epithelium constitutes a crucial defense to the potentially life-threatening effects of gut microbiota. However, due to a complex underlying vasculature, hypoperfusion and resultant tissue ischemia pose a particular risk to function and integrity of the epithelium. The small ubiquitin-like modifier (SUMO) conjugation pathway critically regulates adaptive responses to metabolic stress and is of particular significance in the gut, as inducible knockout of the SUMO-conjugating enzyme Ubc9 results in rapid intestinal epithelial disintegration. Here we analyzed the pattern of individual SUMO isoforms in intestinal epithelium and investigated their roles in intestinal ischemia/reperfusion (I/R) damage. Immunostaining revealed that epithelial SUMO2/3 expression was almost exclusively limited to crypt epithelial nuclei in unchallenged mice. However, intestinal I/R or overexpression of Ubc9 caused a remarkable enhancement of epithelial SUMO2/3 staining along the crypt-villus axis. Unexpectedly, a similar pattern was found in SUMO1 knockout mice. Ubc9 transgenic mice, but also SUMO1 knockout mice were protected from I/R injury as evidenced by better preserved barrier function and blunted inflammatory responses. PCR array analysis of microdissected villus-tip epithelia revealed a specific epithelial contribution to reduced inflammatory responses in Ubc9 transgenic mice, as key chemotactic signaling molecules such as IL17A were significantly downregulated. Together, our data indicate a critical role particularly of the SUMO2/3 isoforms in modulating responses to I/R and provide the first evidence that SUMO1 deletion activates a compensatory process that protects from ischemic damage.
Publication Title
Ubc9 overexpression and SUMO1 deficiency blunt inflammation after intestinal ischemia/reperfusion.
Sample Metadata Fields
Treatment
View Samples- Homo sapiens
- 22 Downloadable Samples
- Affymetrix Human Genome U133A Array (hgu133a)
Description
Asthma is a heterogeneous disease. Exercise-induced bronchoconstriction (EIB) is a distinct syndrome that occurs in 30-50% of asthmatics and is characterized by high levels of pro-inflammatory eicosanoids. We identified genes differentially expressed in the airways of asthmatics with EIB relative to asthmatics without EIB. Genes related to epithelial repair and mast cell infiltration including beta-tryptase and carboxypeptidase A3 were upregulated by exercise challenge in the asthma group with EIB. We confirmed that two novel mediators trefoil factor 3 (TFF3) and transglutaminase 2 (TGM2) have increased expression in airways cells and secreted product in the airways. In vitro studies indicate that 1) TFF3 induces nitric oxide synthase in airway epithelial cells from asthmatics and 2) TGM2 augments the enzymatic activity of secreted phospholipase A2 (sPLA2) group X, an enzyme recently been implicated in asthma pathogenesis. Since PLA2 serves as the first rate-limiting step leading to eicosanoid generation, these results suggest that TGM2 may be a key initiator of the airway inflammatory cascade in asthma.
Publication Title
Transglutaminase 2, a novel regulator of eicosanoid production in asthma revealed by genome-wide expression profiling of distinct asthma phenotypes.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 151 Downloadable Samples
Illumina HumanWG-6 v3.0 expression beadchip
Description
We compared the prognostic significance of ectodomain isoforms of the epidermal growth factor receptor (EGFR), which lack the tyrosine kinase (TK) domain, with that of the full length receptor and its autophosphorylation status in cervical cancers treated with conventional chemoradiotherapy.
Publication Title
Membranous expression of ectodomain isoforms of the epidermal growth factor receptor predicts outcome after chemoradiotherapy of lymph node-negative cervical cancer.
Sample Metadata Fields
Specimen part
View Samples- Rattus norvegicus
- 15 Downloadable Samples
- Affymetrix Rat Gene 1.0 ST Array (ragene10st)
Description
This SuperSeries is composed of the SubSeries listed below.
Publication Title
Role of DNA methylation in the nucleus accumbens in incubation of cocaine craving.
Sample Metadata Fields
Sex, Specimen part
View Samples