Iron loading induces cholesterol synthesis and sensitizes endothelial cells to TNFα-mediated apoptosis
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA708225 | ENA |
REPOSITORIES: ENA
Dataset's files
| Action | DRS | |||
|---|---|---|---|---|
| SRR13912394.fastq.gz | Fastqsanger.gz | |||
| SRR13912395.fastq.gz | Fastqsanger.gz | |||
| SRR13912396.fastq.gz | Fastqsanger.gz | |||
| SRR13912397.fastq.gz | Fastqsanger.gz | |||
| SRR13912398.fastq.gz | Fastqsanger.gz |
Items per page: 5 1 - 5 of 6 |
Similar Datasets
Project description:In plasma, iron is normally bound to transferrin, but in conditions of iron overload when the iron-binding capacity of transferrin is exceeded, non-transferrin-bound iron (NTBI) appears in plasma. NTBI is taken up by hepatocytes and other parenchymal cells via NTBI transporters and can cause cellular damage by promoting the generation of reactive oxygen species. However, how NTBI affects endothelial cells, the most proximal cell type exposed to circulating NTBI, has not been explored. We modeled in vitro the effects of systemic iron overload on endothelial cells by treating primary human umbilical vein endothelial cells (HUVECs) with NTBI (ferric ammonium citrate, FAC). Using an unbiased approach, we showed by RNA-Seq that iron loading alters lipid homeostasis in HUVECs by inducing SREBP2-mediated cholesterol biosynthesis. We also determined that FAC increased the susceptibility of HUVECs to apoptosis induced by TNFα. Moreover, we showed that cholesterol biosynthesis contributes to iron-potentiated apoptosis. Treating HUVECs with a cholesterol chelator hydroxypropyl-β-cyclodextrin demonstrated that depletion of cholesterol was sufficient to rescue HUVECs from TNFa-induced apoptosis, even in the presence of FAC. Finally, we showed that FAC or cholesterol treatment modulated the TNFα pathway by inducing novel proteolytic processing of TNFR1 to a short isoform that localizes to lipid rafts. Our study raises the possibility that iron-mediated toxicity in human iron overload disorders is at least in part dependent on alterations in cholesterol metabolism in endothelial cells, increasing their susceptibility to apoptosis.
2021-09-01 | GSE168534 | GEO
Project description:In plasma, iron is normally bound to transferrin, the principal protein in blood responsible for binding and transporting iron throughout the body. However, in conditions of iron overload when the iron-binding capacity of transferrin is exceeded, non-transferrin-bound iron (NTBI) appears in plasma. NTBI is taken up by hepatocytes and other parenchymal cells via NTBI transporters and can cause cellular damage by promoting the generation of reactive oxygen species. However, how NTBI affects endothelial cells, the most proximal cell type exposed to circulating NTBI, has not been explored. We modeled in vitro the effects of systemic iron overload on endothelial cells by treating primary human umbilical vein endothelial cells (HUVECs) with NTBI (ferric ammonium citrate [FAC]). We showed by RNA-Seq that iron loading alters lipid homeostasis in HUVECs by inducing sterol regulatory element-binding protein 2-mediated cholesterol biosynthesis. We also determined that FAC increased the susceptibility of HUVECs to apoptosis induced by tumor necrosis factor-α (TNFα). Moreover, we showed that cholesterol biosynthesis contributes to iron-potentiated apoptosis. Treating HUVECs with a cholesterol chelator hydroxypropyl-β-cyclodextrin demonstrated that depletion of cholesterol was sufficient to rescue HUVECs from TNFα-induced apoptosis, even in the presence of FAC. Finally, we showed that FAC or cholesterol treatment modulated the TNFα pathway by inducing novel proteolytic processing of TNFR1 to a short isoform that localizes to lipid rafts. Our study raises the possibility that iron-mediated toxicity in human iron overload disorders is at least in part dependent on alterations in cholesterol metabolism in endothelial cells, increasing their susceptibility to apoptosis.
| S-EPMC8463868 | biostudies-literature
Project description:In this study, murine primary aortic smooth muscle cells (SMCs) were transcriptionally profiled at baseline, after 3 d of cholesterol loading, and after 3 d of subsequent cholesterol unloading with HDL treatment, to identify vascular SMC genes that are transcripionally dysregulated in response to cholesterol loading and/or unloading.
2015-02-06 | GSE47744 | GEO
Project description:In this study, murine primary aortic smooth muscle cells (SMCs) were transcriptionally profiled at baseline, after 3 d of cholesterol loading, and after 3 d of subsequent cholesterol unloading with HDL treatment, to identify vascular SMC genes that are transcripionally dysregulated in response to cholesterol loading and/or unloading. Mouse aortic SMCs were isolated from thoracic aortas of 8 week-old C57BL/6 mice (as described in Rong et al., Proc Nat Acad Sci USA, v100, pp13531M-bM-^@M-^S13536, 2003) and subconfluent cell preparations were harvested and transcriptionally profiled (baseline group) or treated with 10 M-NM-<g/mL cholesterol:methyl-M-NM-2-cyclodextrin complex (1:6 molar ratio) for 72 h for cholesterol loading. Of the cholesterol-loaded cells, samples were transcriptionally profiled (cholesterol samples) or treated for an additional 72 h with 100 M-NM-<g/mL human HDL and then transcriptionally profiled (HDL treatment). For all transcriptional profiling, RNA was isolated from cells using TRIzol, and labeled aRNA was prepared for hybridization to Affymetrix Mouse Genome 430 2.0 microarrays according to the manufacturer's protocol. Probe-level intensities were background-adjusted and normalized (in two separate analyses, one with baseline and cholesterol-treated samples, and the other analysis with all three sample groups) using Robust Multichip Average and combined into probesets using probe-to-probeset mappings from the University of Michigan CustomCDF project based on Ensembl Gene identifiers (release 59). Using the data from the analysis that combined the baseline and cholesterol-loaded samples, log2 probeset intensities were compared the between baseline and cholesterol sample groups using a one-way ANOVA with a P value cutoff determined by a Benjamini-Hochberg false discovery rate threshold of 0.05. Analysis (I): baseline and cholesterol-treated sample groups. Analysis (II): all three sample groups.
2015-02-06 | E-GEOD-47744 | biostudies-arrayexpress
Project description:Strain effects on the response to cholesterol loading in bone marrow derived macrophages (BMM) are not well studied. The atherosclerosis susceptible strain, DBA/2 on the ApoE deficient background and the atherosclerosis resistant AKR strains show differences in cholesterol handling when loaded with AcLDL. To understand the molecular basis for these differences, BMM from both strains were loaded with acetylated low desnisty lipoprotein (AcLDL) and gene expression quantified. BMMs from AKR greatly upregulated transcripts involved in the lysosomal trafficking pathway. This experiment strongly suggest that upregualtion of the lysosomal pathway in response to AcLDL maybe protective against atherosclerosis. In addition we find that transcripts containing the sterol response element (SRE) motif had strong strain-loading interactions suggesting a strain response to SRE response.
2013-06-30 | GSE38736 | GEO
Project description:Regulation of endothelial nutrient transport is poorly understood. Vascular endothelial growth factor (VEGF)-B signaling in endothelial cells promotes uptake and transcytosis of fatty acids (FA) from the bloodstream to the underlying tissue, advancing pathological lipid accumulation and lipotoxicity in diabetic complications. Here we demonstrate a VEGF-B dependent obstruction of endothelial glucose transport attributed to plasma membrane lipid alterations affecting glucose transporter 1 function, which was independent of FA uptake. Specifically, VEGF-B signaling impaired recycling of low-density lipoprotein receptor to the plasma membrane, leading to reduced cholesterol uptake and membrane cholesterol loading, decreasing endothelial glucose uptake capacity. Inhibiting VEGF-B in vivo was accordingly linked to reconstitution of membrane cholesterol and induction of glucose uptake, of particular relevance for conditions inferring insulin resistance and diabetic complications. In summary, our study reveals a novel mechanism of action for VEGF-B in endothelial nutrient uptake and highlights the impact of membrane cholesterol for the regulation of endothelial glucose transport.
2020-04-06 | GSE146108 | GEO
Project description:Regulation of endothelial nutrient transport is poorly understood. Vascular endothelial growth factor (VEGF)-B signaling in endothelial cells promotes uptake and transcytosis of fatty acids (FA) from the bloodstream to the underlying tissue, advancing pathological lipid accumulation and lipotoxicity in diabetic complications. Here we demonstrate a VEGF-B dependent obstruction of endothelial glucose transport attributed to plasma membrane lipid alterations affecting glucose transporter 1 function, which was independent of FA uptake. Specifically, VEGF-B signaling impaired recycling of low-density lipoprotein receptor to the plasma membrane, leading to reduced cholesterol uptake and membrane cholesterol loading, decreasing endothelial glucose uptake capacity. Inhibiting VEGF-B in vivo was accordingly linked to reconstitution of membrane cholesterol and induction of glucose uptake, of particular relevance for conditions inferring insulin resistance and diabetic complications. In summary, our study reveals a novel mechanism of action for VEGF-B in endothelial nutrient uptake and highlights the impact of membrane cholesterol for the regulation of endothelial glucose transport.
2020-04-06 | GSE146107 | GEO
Project description:Control, TNFα and TNFα+JNK I treated GSCs
| PRJNA799754 | ENA
Project description:LRP1 and, in particular the region that spans the C-terminal half of domain CR9 (from Gly1127 to Cys1140), named LP3, is essential for aggregated LDL internalization and human coronary vascular smooth muscle cells (hcVSMC)-cholesterol loading. Here, we investigated whether LP3 and its retro-enantio version (DP3) are protective against sphingomyelinase (SMase) and phospholipase 2 (PLA2)-induced LDL aggregation, the structural basis underlying this protection and the impact that LRP1-derived peptides might have on hcVSMC-cholesterol loading and cholesterol-modulated signaling pathways. For this purpose, biochemical, biophysical, molecular, proteomic, and cellular experiments were performed. Turbidimetry measurements show that LP3 and DP3 inhibit LDL aggregation induced by SMase and PLA2 in a dose-dependent manner, although the efficacy of DP3 is higher. Gel filtration chromatography (GFC) and transmission electron microscopy (TEM) show that LP3, and more efficiently DP3, almost completely counteract the increased percentage of aggregated LDL induced by both SMase and PLA2, respectively. Native polyacrilamide gradient gel electrophoresis (GGE), agarose gel electrophoresis (AGE) and high-performance thin layer chromatography (HPTLC) partitioning of LDL phospholipids indicated that LP3 and DP3 prevent SMase-induced alterations in LDL size, electric charge and phospholipid content but not those induced by PLA2. In contrast, LP3 and DP3 show high efficacy to counteract changes in ApoB-100 conformation induced by both SMase and PLA2. Together, these results indicate that LRP1-derived peptides protect LDL against aggregation induced by SMase and PLA2 through a common mechanism based on their capacity to prevent ApoB-100 conformational changes. Proteomics and computational modeling methods suggest that LRP1 derived peptides are able to establish strong electrostatic interactions with a specific ApoB-100 basic region. TLC and confocal microscopy show that DP3 with higher efficacy than LP3 significantly reduce intracellular cholesteryl ester accumulation induced by SMase-LDL in hcVSMC. Moreover, proteomics studies evidence several signaling pathways modulated by SMase-LDL that are counteracted specifically by DP3. These findings demonstrate that LRP1 derivative peptides protect against LDL aggregation and preserve vascular cells against cholesterol loading and associated alterations in critical signal pathways
2019-06-26 | PXD011246 | Pride
Project description:Mouse intestinal epithelial cells (IEC4.1 cells) were stimulated with TNFα (10 ng/ml) for 4h. The Agilent SurePrint G3 Mouse Gene Expression Microarray (G4852A) was used for the analysis, which provides full coverage of genes and transcripts with the most up-to-date content, including mRNAs and lincRNAs (http://www.chem.agilent.com/store/en_US/Prod-G4852A/G4852A). IEC4.1 cells were grown to 80% confluence for four groups: the siRNA control (Group A, cells treated with a non-specific scrambied siRNA control), the TNFα -stimulated (Group B, cells treated with the siRNA control plus TNFα stimulation), lincRNA-Cox2 siRNA (Group C, cells treated with an siRNA to lincRNA-Cox2), and lincRNA-Cox2 siRNA/ TNFα stimulated (Group D, cells treated with the lincNRA-Cox2 siRNA plus TNFα stimulation). Cells were treated with the siRNAs for 24h, followed by additional culture for 4h in the presence or absence of TNFα (10 ng/ml). Total RNAs were prepared with the RNeasy Mini kit (Qiagen) according to the manufacturer’s instruction (Ambion).
2016-10-25 | E-MTAB-3904 | biostudies-arrayexpress