Apoptosis rate and transcriptional response of pancreatic islets exposed to the PPAR gamma agonist Pioglitazone
Ontology highlight
ABSTRACT:
ORGANISM(S): Mus musculus
SUBMITTER: Peter White
PROVIDER: E-GEOD-40119 | biostudies-arrayexpress |
REPOSITORIES: biostudies-arrayexpress
Similar Datasets
Project description:An in vivo and in vitro potato tuber development gene expression study. For in vitro tuber development expression analysis, RNA was isolated from in vitro microtubers at 2, 5, 10, 20 and 30 days following observed tuber induction. Two microtuber populations were used as biological replicates for the developmental stages. The RNA from all developmental stages was pooled to generate the reference samples. Ten microarray hybridizations were performed. For in vivo tuber development expression analysis, RNA was isolated from tubers growing in growth chamber conditions. Tissues were divided into six group, according to developmental size: stolon (no tuber formation), 1-5 mm tubers, 6-10 mm tubers, 11-15 mm tubers, 16-25 mm tubers, and 26-35 mm tubers. Two biological replicates of ten plants each were grown sequentially in the same growth chamber. The RNA from all developmental stages was pooled to generate the reference samples. Twelve microarray hybridizations were performed. For all experiments, the RNA was labeled using the indirect labeling method with random hexamer primers. Amplified cRNA was used as labeling template for stolons. Total RNA was used as labeling template in all other labeling reactions.
2010-07-01 | E-GEOD-5360 | biostudies-arrayexpress
Project description:In vitro expansion of adult human islet M-NM-2 cells is an attractive solution for the shortage of tissue for cell replacement therapy of type 1 diabetes. Using a lineage tracing approach, we have demonstrated that M-NM-2-cell-derived (BCD) cells rapidly dedifferentiate in culture and can proliferate for up to 16 population doublings. Dedifferentiation is associated with changes resembling epithelial-mesenchymal transition (EMT). The WNT pathway has been shown to induce EMT and plays key roles in regulating replication and differentiation in many cell types. Here we show that BCD cell dedifferentiation is associated with M-NM-2-catenin translocation into the nucleus and activation of the WNT pathway. Inhibition of M-NM-2-catenin expression in expanded BCD cells using short hairpin RNA resulted in growth arrest, mesenchymal-epithelial transition, and redifferentiation, as judged by activation of M-NM-2-cell gene expression. Furthermore, inhibition of M-NM-2-catenin expression synergized with redifferentiation induced by a combination of soluble factors, as judged by an increase in the number of C-peptide-positive cells. Simultaneous inhibition of the WNT and NOTCH pathways also resulted in a synergistic effect on redifferentiation. These findings, which were reproducible in cells derived from multiple human donors, suggest that inhibition of the WNT pathway may contribute to a therapeutically applicable way for generation of functional insulin-producing cells following ex-vivo expansion. Gene expression was studied for beta-cells (4 donors). Dedifferentiation was induced by inhibition of M-NM-2-catenin expression using shRNA. The experiment was performed in 4 batches (see the 'Date' characteristic in the Sample records).
2014-08-27 | E-GEOD-60803 | biostudies-arrayexpress
Project description:In the context of T1 Diabetes, pro-inflammatory cytokines IL-1β and IFN-γ are known to contribute to β-cell apoptosis; The measurement of mRNA expression following β-cell exposure to these cytokines gives a picture of the changes in gene expression characterizing the path to β-cell dysfunction and death. Human islets were isolated and exposed (or not) to IL-1β and IFN-γ. The samples were collected at various time points for profiling with Affymetrix arrays. These measurements were performed three times.
2013-12-19 | E-GEOD-53454 | biostudies-arrayexpress
Project description:Nontypeable Haemophilus influenzae (NTHi) is a commensal microorganism of the normal human nasopharyngeal flora, yet also an opportunistic pathogen of the upper and lower respiratory tracts. Changes in gene expression patterns in response to host microenvironments are likely critical for persistence. One such system of gene regulation is the ability to carefully regulate iron uptake. A central regulatory system that controls iron uptake, mediated by the ferric uptake regulator Fur, is present in multiple bacteria, including NTHi. To understand the regulation of iron homeostasis in NTHi, fur was deleted in the prototypic NTHi clinical isolate, 86-028NP. Using an NTHi-specific microarray, we identified genes whose expression was repressed or activated by Fur. These data comprise transcriptional anaylses of a pediatric isolate of NTHi (86-028NP) an rpsL mutant of 86-028NP, a fur mutant of 86-028NP and a fur mutant of 86-028NPrpsL. NTHi parent and fur mutant strains were grown in defined medium containing 10 M-BM-5g /ml human hemoglobin to mid-log phase. Cells were then harvested and RNA extracted. A total of four biological replicates were generated for these analyses.
2013-02-05 | E-GEOD-39874 | biostudies-arrayexpress
Project description:Expression of CD40 in non-hematopoietic cells has been linked to inflammation. We presented evidence that CD40, a T-cell costimulatory molecule, is expressed in human β-cells and the engagement of CD40 in insulinoma cells activated the NFKB and ERK1/2 pathways. CD40 activation in human islets cells induced secretion of IL-8, MCP-1 and MIP-1 β, which is abrogated by inhibitors of NFkB and ERK1/2 inhibitors. In this study, we have studied gene expression mediated by CD40-CD40L interaction in islet cells. This approach identified 90 genes and transcripts exhibiting at least a 1.7 fold increase in their expression intensity after treatment with soluble CD40L. A significant number of genes were related to inflammation and oxidative stress. We have a strong overexpression of CXCL1 (Groα), CXCL2 (Mif2) and CXCL3; chemokines belonging to CXC family structurally related to Il-8. 11 genes were selected from this group and further quantified by Real Time PCR, including CXCL1. Activation of islet cells with CD40L induced the secretion of CXCL1 in a NFKB dependent manner. Engagement of CD40 in islet cells did not induce apoptosis, neither β-cell death and did not enhanced TNF-α mediated cell death as observed in insulinoma cells. CD40 activation in insulinoma cells, results in ERK1/2 dependent phsophorylation of synapsin I, a protein associated with the exocytosis machinery in neurons and β-cells. However, treatment of islets with soluble CD40L did not affect glucose induced insulin secretion. It has been reported that ductal cells always present in human islet preparations express CD40 constitutively (ref). We found that CD40-CD40L interaction in ductal cells, unlike in β-cells, induces secretion of diabetogenic cytokines IFNγ and TNF-α. Furthermore, incubation of islets containing ductal cells with CD40L decreased β-cells viability as assessed by measurement of their mitochondrial membrane potential Experiment Overall Design: We isolated islet cells from three patients. Part of islet cells from each patient has been treated with CD40L. We compared gene expression in treated cells vs untreated for each patient using dye-swap.
2008-10-20 | E-GEOD-8873 | biostudies-arrayexpress
Project description:miRNA expression profiling was performed on MM.1S MM cells cultured 8 hours in control media or 50nM RGB-286638, with or without BMSCs. The emerging role of miRNAs in the pathogenesis of multiple myeloma (MM) led us to hypothesize that the miRNA network might be among the inducible transcriptional alterations consequent to MM-bone marrow stromal cell (BMSC) interactions. Our data suggests that BMSC induced MM transcription led to aberrant miRNA expression. We therefore hypothesized that agents interfering with RNAPII transcription might inhibit aberrant miRNA expression in MM. To test this hypothesis we used RGB-286638, a novel protein kinase inhibitor, which works primarily via RNAPII inhibition followed by transcriptional arrest in MM cells. miRNA profiling of RGB-286638-exposed MM cells resulted in RNAPII arrest associated with reduced miRNA levels. RGB-286638 abrogated BMSCs-induced miRNAs, which correlated with growth arrest in MM cells. Analysis of RGB-286638-induced differentially-expressed miRNAs in MM cells, in the presence or absence of BMSCs, revealed RNAPII regulation of expression of BMSC-inducible miRNAs with established oncogenic functions in MM Our findings demonstrate the role of RNAPII in regulating miRNA network, suggesting a new rationale for using agents interfering with RNAPII transcription in the treatment of MM. TaqMan Low-Density Array (TLDA) using human miRNA version 2.0A and version 3.0B cards (Applied Biosystems) were applied to examine the global change of miRNA expression levels in MM.1S cells when co-cultured with BMSCs, with or without RGB-286638 treatment. A total of 756 mature miRNA updated in the Sanger miRBase v.15.0 were quantified according to the manufacturer's instructions as previously described. miRNAs with Ct values higher than 37 were excluded from the analysis. Normalization was carried out with the mean of RNU44 and RNU48. Relative quantification of miRNA expression was calculated with the 2M-bM-^HM-^RM-NM-^TM-NM-^TCt Ct method using the ddCt program (Shannon McCormack Advanced Molecular Diagnostics Laboratory Research Services). The data was presented as log10 of the relative quantity of each miRNA.
2012-05-31 | E-GEOD-38364 | biostudies-arrayexpress
Project description:Comparative phenotype and transcriptome analyses were performed with Bacillus cereus ATCC 14579 exposed to acid down-shock to pH 5.5 set with different acidulants. When acidified with hydrochloric acid (HCl), growth was diminished, whereas 2 mM undissociated lactic acid (HL) or acetic acid (HAc) stopped growth without inactivation (bacteriostatic condition), and 15 mM undissociated HAc caused growth arrest and, finally, cell death, as reflected by a 3 to 4 log inactivation (bactericidal condition). Within the first 60 min after pH down-shock, the intracellular ATP levels of cultures shocked with HCl were increased. The bacteriostatic pH shocks did not result in increased nor decreased intracellular ATP levels, indicating that the high energy status within the stressed aerobically grown B. cereus cells could be maintained. In contrast, exposure to 15 mM undissociated HAc resulted in significant lower ATP levels, which was in accordance with the observed inactivation. The transcriptomic responses pH down-shocked cultures were studied in the same time frame. The analyses revealed general and specific responses coupled to the different phenotypes and the acidulant used. The general acid stress response, shown in all different pH shocks, involves modulation of pyruvate metabolism and an oxidative stress response. The shifts in pyruvate metabolism include induction dehydrogenases of a butanediol fermentation pathway under non-lethal acid stress conditions and of lactate, formate, and ethanol fermentation pathways under 15 mM HAc stress. Other 15 mM HAc-specific responses were induction of the alternative electron-transport systems, including cydAB, and fatty acid biosynthesis genes. Differences in gene expression for the bacteriostatic organic acid stress conditions compared to the growth-retarded inorganic stress condition indicated a more stringent oxidative stress response, including induction of an additional catalase gene and a gene encoding a Dps-like protein. Moreover, modulations in amino acid and oligopeptide transport were also found for the 2 mM HAc and HL shocks. HL-specific and HAc-specific responses both involve amino acid metabolism. Our study on the genome-wide responses of aerobically grown B. cereus pH 5.5 shocks provides a unique overview of the different responses induced by three acidulants relevant for food preservation. Per acid down-shock three exposure times (i.e., 10, 30 and 60 min) were each compared with non-exposed cells (i.e., t0). In total 4 different pH 5.5 acid down-shocks were applied. pH 5.5 was reached by adding different acidulants i.e., hydrochloric acid (HCl), lactic acid (HL) resulting in 2 mM undissociated HL, acetic acid (HAc) resulting in 15 mM undissociated HAc, and a combination of acetic acid and hydrochloric acid (HAc/HCl) resulting in 2 mM undissociated HAc. The experiments were performed in duplicate and the duplicate samples were hybridised with a dye-swap.
2010-06-25 | E-GEOD-15140 | biostudies-arrayexpress
Project description:To assess whether changes in islet gene expression contribute to differences in phenotypes in response to high fat diet or tretament with pioglitazone, Agilent Whole Mouse Genome Oligo Microarrays were performed on RNA isolated from islets of 4 mice per each treatment group for discovery analysis of gene expression. Male 8 week-old BL6 and BLKS mice were fed normal chow (18% kcal from fat), HFD (42% kcal from fat), or HFD supplemented with the PPAR-γ agonist pioglitazone (PIO) (140 mg PIO/kg diet) for 16 weeks.
2013-09-21 | E-GEOD-51055 | biostudies-arrayexpress
Project description:C57BLKS/J mice are susceptible to diabetes, because of islet dysfunction, whereas C57BL6/J mice are not. Differences in gene expression between the two strains may account for this sensitivity. Furthermore these differences may only be evident in the hyperstimulated (diabetic or hyperglycemic) state. To this end profiling islets from these two strains cultured in both low and high glucose may reveal the underlying mechanism. Keywords: Mouse strain comparison under different culture conditions In the study presented here, pancreatic islets from 20 mice grown in low and high glucose conditions were assayed for differences in gene expression. (five C57BLKS/J low glucose, four C57BLKS/J high glucose, six C57BL6/J low glucose, five C57BL6/J high glucose). Technical replicates are achieved by labeling each sample with both Cy3 and Cy5, and combining the values for each hybridization.
2008-12-30 | E-GEOD-11257 | biostudies-arrayexpress
Project description:Memory T cells respond to stimulation with more rapid expression of effector cell functions than their naM-CM-/ve counterparts, yet the gene expression signature underlying this enhanced recall response is not known. Therefore, we performed comprehensive, whole-genome expression profiling of murine memory CD8 T cells before and shortly after ex vivo stimulation. We compared this differential expression profile to its counterpart from stimulated naive cells. Given that memory cells arise from naive cells, the quiescent state of both cell populations prior to stimulation, and the early time point analyzed (four hours post-stimulation), it was possible that the stimulation-induced changes in gene expression were identical between the two populations. While there was a high degree of overlap, we found that the majority of up-regulated genes were more highly induced following stimulation of memory cells. This more robust increase in transcript levels was observed for a functionally diverse set of genes, including cytokines, chemokines, amino acid metabolic enzymes and transporters, transcription factors and regulators of RNA processing. We also identified the unique, stimulation-induced signatures of naive and memory CD8 T cells and found that the former was enriched for factors involved in regulating chromatin modifications. Specifically, we found that Hdac 5,7 and 8 transcript levels were rapidly down-regulated following stimulation of naive cells, which correlated with an increase in their total level of acetylated histone H3 (AcH3). This was in contrast to stimulated memory cells, which had higher levels of total AcH3 ex vivo that did not change following short-term stimulation. Furthermore, the unique stimulation-induced expression profile of memory cells was enriched for factors involved in regulating transport of molecules between the nucleus and cytoplasm, including multiple members of the nuclear pore complex. Together, these results support a model whereby the chromatin modifications that occur during the differentiation of naM-CM-/ve cells into memory cells are preserved in resting memory populations, facilitating their more robust re-activation of a functionally diverse set of genes that contribute to rapid recall of effector functions. NaM-CM-/ve (CD44lo) and memory phenotype (CD44hi) CD8 T cells from 7-wk old female B6 mice were FACS-purified and cultured in vitro for four hours in the presence or absence of PMA and ionomycin. Total RNA was purified from un-stimulated (resting) naM-CM-/ve, resting memory, stimulated naive, and stimulated memory cells and hybridized to individual single-color arrays. This purification and stimulation protocol was performed four independent times.
2012-05-10 | E-GEOD-16145 | biostudies-arrayexpress