Homo sapiens
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ABSTRACT:
OTHER RELATED OMICS DATASETS IN: E-GEOD-53949
PROVIDER: PRJNA234026 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:RNA-sequencing identifies dysregulation of the human pancreatic islet transcriptome by the saturated fatty acid palmitate
2019-05-14 | E-GEOD-53949 | ExpressionAtlas
Project description:Pancreatic beta-cell dysfunction and death are central in the pathogenesis of type 2 diabetes. Saturated fatty acids cause beta-cell failure and contribute to diabetes development in genetically predisposed individuals. Here we used RNA-sequencing to map transcripts expressed in five palmitate-treated human islet preparations, observing 1,325 modified genes. Palmitate induced fatty acid metabolism and endoplasmic reticulum (ER) stress. Functional studies identified novel mediators of adaptive ER stress signaling. Palmitate modified genes regulating ubiquitin and proteasome function, autophagy and apoptosis. Inhibition of autophagic flux and lysosome function contributed to lipotoxicity. Palmitate inhibited transcription factors controlling beta-cell phenotype including PAX4 and GATA6. 59 type 2 diabetes candidate genes were expressed in human islets, and 11 were modified by palmitate. Palmitate modified expression of 17 splicing factors and shifted alternative splicing of 3,525 transcripts. Ingenuity Pathway Analysis of modified transcripts and genes confirmed that top changed functions related to cell death. DAVID analysis of transcription binding sites in palmitate-modified transcripts revealed a role for PAX4, GATA and the ER stress response regulators XBP1 and ATF6. This human islet transcriptome study identified novel mechanisms of palmitate-induced beta-cell dysfunction and death. The data point to crosstalk between metabolic stress and candidate genes at the beta-cell level. 5 human islet of Langerhans preparations examined under 2 conditions (control and palmitate treatment)
2014-01-09 | E-GEOD-53949 | biostudies-arrayexpress
Project description:Pancreatic beta-cell dysfunction and death are central in the pathogenesis of type 2 diabetes. Saturated fatty acids cause beta-cell failure and contribute to diabetes development in genetically predisposed individuals. Here we used RNA-sequencing to map transcripts expressed in five palmitate-treated human islet preparations, observing 1,325 modified genes. Palmitate induced fatty acid metabolism and endoplasmic reticulum (ER) stress. Functional studies identified novel mediators of adaptive ER stress signaling. Palmitate modified genes regulating ubiquitin and proteasome function, autophagy and apoptosis. Inhibition of autophagic flux and lysosome function contributed to lipotoxicity. Palmitate inhibited transcription factors controlling beta-cell phenotype including PAX4 and GATA6. 59 type 2 diabetes candidate genes were expressed in human islets, and 11 were modified by palmitate. Palmitate modified expression of 17 splicing factors and shifted alternative splicing of 3,525 transcripts. Ingenuity Pathway Analysis of modified transcripts and genes confirmed that top changed functions related to cell death. DAVID analysis of transcription binding sites in palmitate-modified transcripts revealed a role for PAX4, GATA and the ER stress response regulators XBP1 and ATF6. This human islet transcriptome study identified novel mechanisms of palmitate-induced beta-cell dysfunction and death. The data point to crosstalk between metabolic stress and candidate genes at the beta-cell level.
2014-01-09 | GSE53949 | GEO
Project description:Gene expression pattern in murine 3T3-L1 adipocytes treated with saturated fatty acid (palmitate) in the presence or absence of PI3K p110alpha-selective inhibitor A66.
2020-01-01 | GSE129442 | GEO
Project description:Background: Long-term exposure to elevated levels of free fatty acids (FFAs) is deleterious for beta-cell function and may contribute to development of type 2 diabetes mellitus (T2DM). Whereas mechanisms of impaired glucose-stimulated insulin secretion (GSIS) in FFA-treated beta-cells have been intensively studied, biological events preceding the secretory failure, when GSIS is accentuated, are poorly investigated. To identify these early events, we performed genome-wide analysis of gene expression in isolated human islets exposed to fatty acid palmitate for different time periods. Results: Palmitate-treated human islets showed decline in beta-cell function starting from day two. Affymetrix Human Transcriptome Array 2.0 identified 903 differentially expressed genes (DEGs). Mapping of the genes onto pathways using KEGG pathway enrichment analysis predicted four islet biology-related pathways enriched prior but not after the decline of islet function and three pathways enriched both prior and after the decline of islet function. DEGs from these pathways were analyzed at the transcript level. The results propose that in palmitate-treated human islets, at early time points, protective events, including up-regulation of metallothioneins, tRNA synthetases and fatty acid-metabolising proteins, dominate over deleterious events, including inhibition of fatty acid detoxification enzymes, which contributes to the enhanced GSIS. After prolonged exposure of islets to palmitate, the protective events are outweighed by the deleterious events, which leads to impaired GSIS. Conclusions: The study identifies temporal order between different cellular events, which either promote or protect from beta-cell failure. The sequence of these events should be considered when developing strategies for prevention and treatment of the disease.
2018-08-19 | GSE118230 | GEO
Project description:Background: Prolonged exposure to elevated free fatty acids induces β-cell failure (lipotoxicity) and contributes to the pathogenesis of type 2 diabetes. In vitro exposure of β-cells to the saturated free fatty acid palmitate is a valuable model of lipotoxicity, reproducing features of β-cell failure observed in type 2 diabetes. In order to map the β-cell response to lipotoxicity, we combined RNA-sequencing of palmitate-treated human islets with iTRAQ proteomics of insulin-secreting INS-1E cells following a time course exposure to palmitate. Results: Crossing transcriptome and proteome of palmitate-treated β-cells revealed 85 upregulated and 122 downregulated genes at both transcript and protein level. Pathway analysis identified lipid metabolism, oxidative stress, amino-acid metabolism and cell cycle pathways among the most enriched palmitate-modified pathways. Palmitate induced gene expression changes compatible with increased free fatty acid mitochondrial import and β-oxidation, decreased lipogenesis and modified cholesterol transport. Palmitate modified genes regulating endoplasmic reticulum (ER) function, ER-to-Golgi transport and ER stress pathways. Furthermore, palmitate modulated cAMP/protein kinase A (PKA) signaling, inhibiting expression of PKA anchoring proteins and downregulating the GLP-1 receptor. SLC7 family amino-acid transporters were upregulated in response to palmitate but this induction did not contribute to β-cell demise. To unravel critical mediators of lipotoxicity upstream of the palmitate-modified genes, we identified overrepresented transcription factor binding sites and performed network inference analysis. These identified LXR, PPARα, FOXO1 and BACH1 as key transcription factors orchestrating the metabolic and oxidative stress responses to palmitate. Conclusions: This is the first study to combine transcriptomic and sensitive time course proteomic profiling of palmitate-exposed β-cells. Our results provide comprehensive insight into gene and protein expression changes, corroborating and expanding beyond previous findings. The identification of critical drivers and pathways of the β-cell lipotoxic response points to novel therapeutic targets for type 2 diabetes.
2020-08-13 | GSE156109 | GEO
Project description:ANGPTL4 regulates plasma triglyceride levels by inhibiting lipoprotein lipase. Inactivation of ANGPTL4 decreases plasma triglycerides and reduces risk of coronary artery disease. Unfortunately, targeting ANGPTL4 for the therapeutic management of dyslipidemia and atherosclerosis is hampered by the observation that mice and monkeys in which ANGPTL4 is inactivated exhibit lipid accumulation in mesenteric lymph nodes. In mice these pathological events exclusively unfold upon feeding a high saturated fatty acid diet and are followed by an ultimately lethal pro-inflammatory response and chylous ascites. Here we show that Angptl4-/- mice fed a diet rich in trans fatty acids develop numerous lipid-filled giant cells in their mesenteric lymph nodes, yet do not have elevated serum amyloid and haptoglobin, do not exhibit ascites, and survive, unlike Angptl4-/- mice fed a saturated fatty acid-rich diet. In RAW264.7 macrophages the saturated fatty acid palmitate markedly increases markers of inflammation and the unfolded protein response, whereas the trans-unsaturated elaidate and the cis-unsaturated oleate have the opposite effect. In conclusion, trans and saturated fatty acids have very distinct biological effects. Furthermore, lipid accumulation in mesenteric lymph nodes is uncoupled from activation of an acute-phase response and chylous ascites, suggesting that ANGPTL4 should not be fully dismissed as target for dyslipidemia.
2017-04-27 | GSE98303 | GEO
Project description:DNA microarray analysis was performed to investigate the expression of genes in HGF stimulated with palmitate Type 2 diabetes (T2D) is characterized by decreased insulin sensitivity and higher concentrations of free fatty acids (FFAs) in plasma. Among FFAs, saturated fatty acids (SFAs), such as palmitate, have been proposed to promote inflammatory responses. Although many epidemiological studies have shown a link between periodontitis and T2D, little is known about the clinical significance of SFAs in periodontitis. The goal of this study is to demonstrate a potential link between the pathogenesis of periodontitis and SFAs in plasma. HGF were treated with either with 0 (1% Bovine serum albumin) or 100 µM Palmitate for 36 hours (n=2 each).
2015-12-31 | E-GEOD-62761 | biostudies-arrayexpress
Project description:To identify mediators of obesity-linked reductions in PGC-1, we tested the effects of cellular nutrients in C2C12 myotubes. While overnight exposure to high insulin, glucose, glucosamine, or amino acids had no effect, saturated fatty acids (FA) potently reduced PGC-1a and b mRNA expression. Experiment Overall Design: Cell culture - Mouse C2C12 myoblasts (ATCC, Manassas, VA) were maintained in Dulbecco's modified Eagle's medium (DMEM) supplemented with 20% fetal bovine serum (Invitrogen), at a confluency of 60-70%. To initiate differentiation, cells were allowed to reach 100% confluency and medium was changed to DMEM containing 2% horse serum (Invitrogen) and changed every 2 days. Full differentiation, with myotube fusion and spontaneous twitching, was observed at 5 days. Fatty acid stock preparation - Fatty acids were dissolved in 0.1 N sodium hydroxide (final concentration 100 mM) at 65 degrees C for 2 hours and then complexed with 10% fatty acid-free BSA, yielding a final stock of 5 mM. Three replicates for each fatty-acid. Microarray analysis - RNA was isolated as described from C2C12 myotubes treated overnight with 500 uM palmitate or 1% BSA, and cRNA was synthesized. 10 mg of cRNA were hybridized to Affymetrix mouse 430A 2.0 arrays. Intensity values were quantified using MAS 5.0 software. MAPPFinder (www.genmapp.org) was used to integrate expression data with known pathways. Transcription profiling of mouse C2C12 myotubes treated overnight with 500 uM palmitate or 1% BSA to identify mediators of obesity-linked reductions in PGC-1.
2007-11-15 | E-GEOD-6766 | biostudies-arrayexpress
Project description:Stearoyl-CoA desaturase (SCD) is the rate-limiting enzyme catalyzing the conversion of saturated fatty acids palmitate and stearate to monounsaturated fatty acids palmitoleate and oleate. During adipocyte differentiation, SCD expression increases concomitantly with several transcription factors and lipogenic genes. We used microarrays to examine gene expression in differentiated pre-adipocytes treated with and without an SCD inhibitor.
2014-04-04 | GSE51905 | GEO