The peroxisome proliferator-activated receptor alpha (PPAR) is a fatty acid-activated transcription factor that governs a variety of biological processes. Little is known about the role of PPAR in the small intestine. Since this organ is frequently exposed to high levels of PPAR ligands via the diet, we set out to characterize the function of PPAR in small intestine using functional genomics experiments and bioinformatics tools. PPAR was expressed at high levels in both human and murine small intestine. Detailed analyses showed that PPAR was expressed highest in villus cells of proximal jejunum. Microarray analyses of total tissue samples revealed, that in addition to genes involved in fatty acid and triacylglycerol metabolism, transcription factors and enzymes connected to sterol and bile acid metabolism, including FXR and SREBP1, were specifically induced. In contrast, genes involved in cell cycle and differentiation, apoptosis, and host defense were repressed by PPAR activation. Additional analyses showed that intestinal PPAR dependent gene regulation occurred in villus cells. Functional implications of array results were corroborated by morphometric data. The repression of genes involved in proliferation and apoptosis was accompanied by a 22% increase in villus height, and a 34% increase in villus area of wild-type animals treated with WY14643. This is the first report providing a comprehensive overview of processes under control of PPAR in the small intestine. We show that PPAR is an important transcriptional regulator in small intestine, which may be of importance for the development of novel foods and therapies for obesity and inflammatory bowel diseases.
Genome-wide analysis of PPARalpha activation in murine small intestine.
Sex, Age, Specimen part
View SamplesGene expression regulation of transporters and phase I/II metabolic enzymes in murine small intestine during fasting
Gene expression of transporters and phase I/II metabolic enzymes in murine small intestine during fasting.
Sex, Age, Specimen part
View SamplesFindings suggest that PPARalpha plays a decisive role in the development of hypertrophy, affecting the functional outcome of the heart. Unfortunately, information on the nature of PPARalpha-dependent processes in cardiac hypertrophy is fragmentary and incomplete.
Transcriptomic analysis of PPARalpha-dependent alterations during cardiac hypertrophy.
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View SamplesTo understand how haploinsufficiency of progranulin (PGRN) protein causes frontotemporal dementia (FTD), we created induced pluripotent stem cells (iPSC) from patients carrying the GRNIVS1+5G>C mutation (FTD-iPSCs). FTD-iPSCs were fated to cortical neurons, the cells most affected in FTD and known to express PGRN. Although generation of neuroprogenitors was unaffected, their further differentiation into neurons, especially CTIP2-, FOXP2- or TBR1-TUJ1 double positive cortical neurons, was significantly decreased in FTD-neural progeny. Zinc finger nuclease-mediated introduction of PGRN cDNA into the AAVS1 locus corrected defects in cortical neurogenesis, demonstrating that PGRN haploinsufficiency causes inefficient cortical neuron generation. RNAseq analysis confirmed reversal of altered gene expression profile following genetic correction. Wnt signaling pathway, one of the top defective pathways in FTD-iPSC-derived neurons coupled with its reversal following genetic correction, makes it an important candidate. Therefore, we demonstrate for the first time that PGRN haploinsufficiency hampers corticogenesis in vitro. Overall design: We profiled 6 samples: two biological replicates for 3 conditions. Condition 1 consists of neuronal progeny derived from human Embryonic Stem Cells. Condition 2 consists of neuronal progeny derived from induced pluripotent stem cells generated from patients carrying PGRN mutation. Condition 3 consists of neuronal progeny derived from induced pluripotent stem cells generated from patients carrying PGRN mutation, genetically modified to correct the PGRN defect.
Restoration of progranulin expression rescues cortical neuron generation in an induced pluripotent stem cell model of frontotemporal dementia.
No sample metadata fields
View SamplesWe studied the effect of dietary fat type, varying in polyunsaturated/saturated fatty acid ratio's (P/S) on development of metabolic syndrome. C57Bl/6J mice were fed purified high-fat diets (45E% fat) containing palm oil (HF-PO; P/S 0.4), olive oil (HF-OO; P/S 1.1) or safflower oil (HF-SO; P/S 7.8) for 8 weeks. A low-fat palm oil diet (LF-PO; 10E% fat) was used as a reference. Additionally, we analyzed diet-induced changes in gut microbiota composition and mucosal gene expression. The HF-PO diet induced a higher body weight gain and liver triglyceride content compared to the HF-OO, HF-SO or LF-PO diet. In the intestine, the HF-PO diet reduced microbial diversity and increased the Firmicutes/Bacteroidetes ratio. Although this fits a typical obesity profile, our data clearly indicate that an overflow of the HF-PO diet to the distal intestine, rather than obesity itself, is the main trigger for these gut microbiota changes. A HF-PO diet-induced elevation of lipid metabolism-related genes in the distal small intestine confirmed the overflow of palm oil to the distal intestine. Some of these lipid metabolism-related genes were previously already associated with the metabolic syndrome. In conclusion, our data indicate that saturated fat (HF-PO) has a more stimulatory effect on weight gain and hepatic lipid accumulation than unsaturated fat (HF-OO and HF-SO). The overflow of fat to the distal intestine on the HF-PO diet induced changes in gut microbiota composition and mucosal gene expression. We speculate that both are directly or indirectly contributive to the saturated fat-induced development of obesity and hepatic steatosis.
Saturated fat stimulates obesity and hepatic steatosis and affects gut microbiota composition by an enhanced overflow of dietary fat to the distal intestine.
Sex, Specimen part
View SamplesMesenchymal stromal cells (MSCs) are multipotent stem cells with potent immunosuppressive and trophic support functions. Although bone marrow is considered the golden standard to isolate classical MSCs (BM-MSC), MSC-like cells are currently also derived from other, more easily accessible extra-embryonic tissues such as the umbilical cord. In this study we compared the gene expression profile of human Wharton's jelly explant-derived MSC cultures with two adult MSC populations derived from bone marrow, namely BM-MSC and multipotent adult progenitor cells (MAPC).
Human Wharton's Jelly-Derived Stem Cells Display a Distinct Immunomodulatory and Proregenerative Transcriptional Signature Compared to Bone Marrow-Derived Stem Cells.
Specimen part
View SamplesThe objective of this study was to compare recall responses to vaccine antigens at 3 months and 9 months of age in infants who were vaccinated at birth or at 1 month.
Pneumococcal conjugate vaccination at birth in a high-risk setting: no evidence for neonatal T-cell tolerance.
Age, Specimen part, Treatment
View SamplesThe polarization of macrophages into an anti-inflammatory or regulatory phenotype plays an important role in resolving inflammation. PGE2 regulates macrophage polarization via a PKA dependent pathway. PKA phosphorylates SIKs, inhibiting their ability to phosphorylate CRTC3 in cells. This in turn allows CRTC3 to translocate to the nucleus where it acts as a co-activator with the transcription factor CREB to induce IL-10 transcription. In line with this we find that either genetic or pharmacological inhibition of SIKs mimics the effect of PGE2 on IL-10 production.
PGE(2) induces macrophage IL-10 production and a regulatory-like phenotype via a protein kinase A-SIK-CRTC3 pathway.
Specimen part
View SamplesGlucocorticoid resistance (GCR) is defined as an unresponsiveness to the anti-inflammatory properties of glucocorticoids (GCs) and their receptor, the glucocorticoid receptor (GR). It is a serious problem in the management of inflammatory diseases and occurs frequently. The strong pro-inflammatory cytokine TNF induces an acute form of GCR, not only in mice, but also in several cell lines, e.g. in the hepatoma cell line BWTG3, as evidenced by impaired Dexamethasone (Dex)-induced GR-dependent gene expression. We report that TNF has a significant and broad impact on the transcriptional performance of GR, but no impact on nuclear translocation, dimerization or DNA binding capacity of GR. Proteome-wide proximity-mapping (BioID), however, revealed that the GR interactome is strongly modulated by TNF. One GR cofactor that interacts significantly less with the receptor under GCR conditions is p300. NF?B activation and p300 knockdown both reduce transcriptional output of GR, whereas p300 overexpression and NF?B inhibition revert TNF-induced GCR, which is in support of a cofactor reshuffle model. This hypothesis is supported by FRET studies. This mechanism of GCR opens new avenues for therapeutic interventions in GCR diseases Overall design: Examination of GR induced gene expression in 4 conditions (1 control: NI and 3 treated: DEX, TNF, TNFDEX) starting from 3 biological replicates
TNF-α inhibits glucocorticoid receptor-induced gene expression by reshaping the GR nuclear cofactor profile.
Specimen part, Cell line, Treatment, Subject
View SamplesActivation of macrophages by inflammatory stimuli leads to reprogramming of mitochondrial metabolism to support the production of pro-inflammatory cytokines. Hallmarks of this metabolic rewiring are downregulation of a-ketoglutarate formation via isocitrate dehydrogenase (IDH) and accumulation of glutamine-derived succinate, which enhances the inflammatory response via the activity of succinate dehydrogenase (SDH). Here, we identify the nuclear receptor Nur77 (Nr4a1) as a key regulator of the pro-inflammatory metabolic switch in macrophages. Nur77-deficient macrophages fail to downregulate IDH expression and accumulate higher levels of succinate and other downstream TCA cycle metabolites in response to an inflammatory stimulus. Consequently, these macrophages produce more nitric oxide and pro-inflammatory cytokines in an SDH-dependent manner. In vivo, bone marrow Nur77 deficiency exacerbates atherosclerosis development and leads to increased systemic succinate levels. In conclusion, Nur77 supports an anti-inflammatory metabolic state in macrophages that protects against chronic inflammatory diseases such as atherosclerosis. Overall design: Gene expression profiling by RNA-seq was performed in triplicate in RAW264.7 mouse macrophage stable cell lines with doxycycline-inducible overexpression of HA-tagged NUR77 or GFP as control.
Nuclear Receptor Nur77 Limits the Macrophage Inflammatory Response through Transcriptional Reprogramming of Mitochondrial Metabolism.
Cell line, Treatment, Subject
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