Major causes of lipid accumulation in liver are increased import, synthesis or decreased catabolism of fatty acids. The latter is caused by dysfunction of cellular organelle controlling energy homeostasis, i.e. mitochondria. However, peroxisomes appear to be an important organelle in lipid metabolism of hepatocytes, but little is known about their role in the development of non-alcoholic fatty liver disease (NAFLD). To investigate the role of peroxisomes next to mitochondria in excessive hepatic lipid accumulation we used the leptin resistant db/db mice on C57BLKS background, a mouse model that develops hyperphagia induced diabetes with obesity and NAFLD.
Peroxisomes compensate hepatic lipid overflow in mice with fatty liver.
Sex, Age, Specimen part
View SamplesVasopressin is the major hormone that regulates renal water excretion. It does so by binding to a receptor in renal collecting duct cells, triggering signaling pathways that ultimately regulate the abundance, location, and activity of the water channel protein aquaporin 2. We took an advantage of quantitative large scale proteomic technologies and oligonucleotide microarrays to quantify steady state changes in protein and transcript abundances in response to vasopressin in a collecting duct cell line, mpkCCD clone 11 (Yu et al. PNAS 2009, 106:2441-2446). This cell line originally developed by Alan Vandewalles group recapitulates vasopressin-mediated AQP2 expression and phosphorylation as seen in native colleting duct cells.
Quantitative protein and mRNA profiling shows selective post-transcriptional control of protein expression by vasopressin in kidney cells.
Specimen part, Cell line
View SamplesWe used an in vitro cardiomyocyte differentiation system with inducible Hey1 or Hey2 expression to study target gene regulation in cardiomyocytes (CM) generated from murine embryonic stem cells (ESC). The effects of Hey1 and Hey2 are largely redundant, but cell type specific. The number of regulated genes is comparable between ESC and CM, but the total number of binding sites is much higher, especially in ESC, targeting mainly genes involved in transcriptional regulation and developmental processes. Repression by Hey generally correlates with the extent of Hey-binding to target promoters, subsequent Hdac recruitment and lower histone acetylation. Functionally, treatment with the Hdac inhibitor TSA abolished Hey target gene regulation. However, in CM the repressive effect of Hey-binding is lost for a subset of genes. These lack Hey-dependent histone deacetylation in CM and are enriched for binding sites of cardiac specific activators like Srf, Nkx2-5, and Gata4.
Mechanisms of epigenetic and cell-type specific regulation of Hey target genes in ES cells and cardiomyocytes.
No sample metadata fields
View SamplesA series contains a set of transcript intensity values measured by Affymetrix microarray.
Systems-level analysis of cell-specific AQP2 gene expression in renal collecting duct.
Sex, Specimen part
View SamplesThis series of microarray data contain transcript intensity of mpkCCD cells.
Systems-level analysis of cell-specific AQP2 gene expression in renal collecting duct.
No sample metadata fields
View SamplesBackground
Similar inflammatory DC maturation signatures induced by TNF or Trypanosoma brucei antigens instruct default Th2-cell responses.
Specimen part, Treatment
View Samplesprenatal stress response, genetic modification
Differential effects of prenatal stress in 5-Htt deficient mice: towards molecular mechanisms of gene × environment interactions.
Sex, Specimen part, Treatment
View SamplesIn this study that was specifically designed to identify early stages of glaucoma in DBA/2J mice, we used genome-wide expression profiling and a series of computational methods. Our methods successfully subdivided eyes with no detectable glaucoma by conventional assays into molecularly defined stages of disease. These stages represent a temporally ordered sequence of glaucoma states. Using an array of tools, we then determined networks and biological processes that are altered at these early stages. Our strategy proved very sensitive, suggesting that similar approaches will be valuable for uncovering early processes in other complex, later-onset diseases. Early changes included upregulation of both the complement cascade and endothelin system, and so we tested the therapeutic value of separately inhibiting them. Mice with a mutation in the complement component 1a gene (C1qa) were robustly protected from glaucoma with the protection being among the greatest reported. Similarly, inhibition of the endothelin system was strongly protective. Since EDN2 is potently vasoconstrictive and was produced by microglial/macrophages, our data provide a novel link between these cell types and vascular dysfunction in glaucoma. Targeting early events such as the upregulation of the complement and endothelin pathways may provide effective new treatments for human glaucoma.
Molecular clustering identifies complement and endothelin induction as early events in a mouse model of glaucoma.
Sex, Age, Specimen part
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