This SuperSeries is composed of the SubSeries listed below.
MicroRNAs are transported in plasma and delivered to recipient cells by high-density lipoproteins.
Sex, Age, Cell line, Treatment
View SamplesCirculating microRNAs (miRNA) are relatively stable in plasma and are a new class of disease biomarkers. Here we present evidence that human high-density lipoprotein (HDL) transports endogenous miRNAs and delivers them to recipient cells with functional targeting capabilities. Highly-purified fractions of human HDL contain small RNAs, and the HDL-miRNA profile from normal subjects is significantly different than familial hypercholesterolemia subjects. miRNAs were demonstrated to associate with both native and reconstituted HDL particles, and reconstituted HDL injected into mice retrieved distinct miRNA profiles from normal and atherogenic models. Cellular export of miRNAs to HDL was demonstrated to be regulated by neutral sphingomyelinase. HDL-mediated delivery of miRNAs to recipient cells was demonstrated to be scavenger receptor BI-dependent. Furthermore, HDL delivery of both exogenous and endogenous miRNAs resulted in the direct targeting of mRNA reporters. Notably, HDL-miRNA from atherosclerotic subjects induced differential gene expression, with significant loss of conserved mRNA targets in cultured hepatocytes. Collectively, these observations suggest that HDL participates in a novel mechanism of intercellular communication involving the transport and delivery of miRNAs.
MicroRNAs are transported in plasma and delivered to recipient cells by high-density lipoproteins.
Cell line, Treatment
View SamplesThe cleavage of sphingoid base phosphates by sphingosine-1-phosphate (S1P) lyase to produce phosphoethanolamine and a fatty aldehyde is the final degradative step in the sphingolipid metabolic pathway. We have studied mice with an inactive S1P lyase gene and have found that, in addition to the expected increase of sphingoid base phosphates, other sphingolipids (including sphingosine, ceramide, and sphingomyelin) were substantially elevated in the serum and /or liver of these mice. This latter increase is consistent with a reutilization of the sphingosine backbone for sphingolipid synthesis due to its inability to exit the sphingolipid metabolic pathway. Furthermore, the S1P lyase deficiency resulted in changes in the levels of serum and liver lipids not directly within the sphingolipid pathway, including phospholipids, triacyglycerol, diacylglycerol, and cholesterol. Even though lipids in serum and lipid storage were elevated in liver, adiposity was reduced in the S1P lyase-deficient mice. Microarray analysis of lipid metabolism genes in liver showed that the S1P lyase deficiency caused widespread changes in their expression pattern. These results demonstrate that S1P lyase is a key regulator of the levels of multiple sphingolipid substrates and reveal functional links between the sphingolipid metabolic pathway and other lipid metabolic pathways that may be mediated by shared lipid substrates and changes in gene expression programs. The disturbance of lipid homeostasis by altered sphingolipid levels may be relevant to metabolic diseases.
Sphingosine 1-phosphate lyase deficiency disrupts lipid homeostasis in liver.
Specimen part
View SamplesHigh fat diets are known to be a risk factor for prostate cancer. In this study, we investigated the effect of high fat diet on mouse prostate gene expression. C57BL/6J mice were fed either a control or high fat diet for 12 weeks. Microarray analyses were performed on mouse ventral prostate (VP) and dorsolateral prostate (DLP), followed by canonical pathway analysis and regulatory network identification. mRNA changes were confirmed by real time PCR. Approximately 2,125, and 1,194 genes responded significantly to the high fat diet in VP, DLP, respectively. Pathways and networks related to oxidative stress, glutathione metabolism, NRF-mediated oxidative stress response and NF-kappaB were all differentially regulated by high fat diet. GPx3 mRNA levels were decreased by approximately 2-fold by high fat diet in all 3 prostate lobes. In human non-transformed prostate cells (PrSC, PrEC and BPH-1), cholesterol loading decreased GPx3 expression, and increased H2O2 levels of culture medium. Troglitazone increased GPx3 expression in 3 normal prostate cells, and decreased H2O2 levels. In addition, troglitazone attenuated cholesterol-induced H2O2 increase. Tissue from prostate cancer biopsies had decreased GPx3 mRNA and its level was inversely related to the Gleason score.
High fat diet reduces the expression of glutathione peroxidase 3 in mouse prostate.
No sample metadata fields
View SamplesWe quantified differential gene (mRNA) expression in human coronary artery cells treated with native HDL, reconstituted HDL, lipid-free apolipoprotein A-I, small unilamellar vesicles, or PBS control.
HDL-transferred microRNA-223 regulates ICAM-1 expression in endothelial cells.
Specimen part
View SamplesChanges in the transcript profile due to ABCA1 expression in murine liver samples was evaluated in LDL receptor -/- genetic backgrounds.
ABCA1 overexpression in the liver of LDLr-KO mice leads to accumulation of pro-atherogenic lipoproteins and enhanced atherosclerosis.
Sex, Specimen part
View SamplesMolecular pathways activated in MALT lymphoma are not well defined.
Gene expression profiling of pulmonary mucosa-associated lymphoid tissue lymphoma identifies new biologic insights with potential diagnostic and therapeutic applications.
Sex
View SamplesHepatitis C Virus is a leading cause of chronic liver disease. The identification and characterisation of key host cellular factors that play a role in the HCV replication cycle is important for the understanding of disease pathogenesis and the identification of novel anti-viral therapeutic targets. Gene expression profiling of HCV infected Huh7 cells by microarray analysis was performed to identify host cellular genes that are transcriptionally regulated by infection. The expression of host genes involved in cellular defence mechanisms (apoptosis, proliferation and anti-oxidant responses), cellular metabolism (lipid and protein metabolism) and intracellular transport (vesicle trafficking and cytoskeleton regulation) was significantly altered by HCV infection. The gene expression patterns identified provide insight into the potential mechanisms that contribute to HCV associated pathogenesis. These include an increase in pro-inflammatory and pro-apoptotic signalling and a decrease in the anti-oxidant response pathways of the infected cell.
Gene expression profiling indicates the roles of host oxidative stress, apoptosis, lipid metabolism, and intracellular transport genes in the replication of hepatitis C virus.
Specimen part, Cell line
View SamplesThis SuperSeries is composed of the SubSeries listed below.
GENE REGULATION. Discrete functions of nuclear receptor Rev-erbα couple metabolism to the clock.
Specimen part, Time
View SamplesCircadian and metabolic physiology are intricately intertwined, as illustrated by Rev-erb , a transcription factor (TF) that functions both as a core repressive component of the cell autonomous clock and as a regulator of metabolic genes. Here we show that Rev-erb modulates the clock and metabolism by different genomic mechanisms. Clock control requires Rev-erb to bind directly to the genome at its cognate sites, where it competes with activating ROR TFs. By contrast, Rev-erb regulates metabolic genes primarily by recruiting the HDAC3 corepressor to sites to which it is tethered by cell type-specific transcription factors. Thus, direct competition between Rev-erb and ROR TFs provides a universal mechanism for self-sustained control of molecular clock across all tissues, whereas Rev-erb utilizes lineage-determining factors to convey a tissue-specific epigenomic rhythm that regulates metabolism tailored to the specific need of that tissue.
GENE REGULATION. Discrete functions of nuclear receptor Rev-erbα couple metabolism to the clock.
Specimen part, Time
View Samples