Statins, the 3-hydroxy-3-methyl-glutaryl (HMG)-CoA reductase inhibitors, are widely prescribed for treatment of hypercholesterolemia. Although statins are generally well tolerated, up to ten percent of patients taking statins experience muscle related adverse events. Myalgia, defined as muscle pain without elevated creatinine phosphokinase (CPK) levels, is the most frequent reason for discontinuation of statin therapy. The mechanisms underlying statin-associated myalgia are not clearly understood. To elucidate changes in gene expression associated with statin-induced myalgia, we compared profiles of gene expression in the biopsied skeletal muscle from statin-intolerant patients undergoing statin re-challenge versus those of statin-tolerant controls. A robust separation of statin-intolerant and statin-tolerant cohorts was revealed by Principal Component Analysis of differentially expressed genes (DEGs). To identify putative gene expression and metabolic pathways that may be perturbed in skeletal muscles of statin intolerant patients, we subjected DEGs to Ingenuity Pathways (IPA) and DAVID (Database for Annotation, Visualization and Integrated Discovery) analyses. The most prominent pathways altered by statins included cellular stress, apoptosis, senescence and DNA repair (TP53, BARD1, Mre11 and RAD51); activation of pro-inflammatory immune response (CXCL12, CST5, POU2F1); protein catabolism, cholesterol biosynthesis, protein prenylation and RAS-GTPase activation (FDFT1, LSS, TP53, UBD, ATF2, H-ras). Based on these data we tentatively conclude that persistent myalgia in response to statins may emanate from cellular stress underpinned by mechanisms of post-inflammatory repair and regeneration. We also posit that this subset of individuals are genetically predisposed to eliciting altered statin metabolism and/or increased end-organ susceptibility that lead to a range of statin-induced myopathies. This mechanistic scenario further bolstered by the discovery that a number of single nucleotide polymorphisms (e.g., SLCO1B1, SLCO2B1 and RYR2) associated with statin myopathy were observed with increased frequency among statin-intolerant study subjects.
Patients experiencing statin-induced myalgia exhibit a unique program of skeletal muscle gene expression following statin re-challenge.
Specimen part
View SamplesCD4+ cells from Foxp3.eGFP mice containing Foxp3- Teff and Foxp3+ Treg cells were treated with anti-CD3/CD28 monoclonal antibodies or soluble OX40L and JAG1 for 3 days to induce TCR-dependent vs TCR-independent Treg proliferation. Untreated fresh CD4+ T-cells used as control. Post treatment T-cell proliferation was confirmed by Cell Trace violet dilution and Foxp3+ (Treg) and Foxp3-(Teff) were sorted. Differential gene expression profiling between Tregs and Teff cells among control, anti-CD3/CD28 and OX40L-JAG1 treated cultured was performed using affymetrix mouse gene 2.0 ST micro array.
OX40L-JAG1-Induced Expansion of Lineage-Stable Regulatory T Cells Involves Noncanonical NF-κB Signaling.
Specimen part, Treatment
View SamplesRoom temperature whole blood mRNA stabilization procedures, such as the PAX gene system, are critical for the application of transcriptional analysis to population-based clinical studies. Global transcriptome analysis of whole blood RNA using microarrays has proven to be challenging due to the high abundance of globin transcripts that constitute 70% of whole blood mRNA in the blood. This is a particular problem in patients with sickle-cell disease, secondary to the high abundance of globin-expressing nucleated red blood cells and reticulocytes in the circulation . In order to more accurately measure the steady state whole blood transcriptome in sickle-cell patients, we evaluated the efficacy of reducing globin transcripts in PAXgene stabilized RNA samples for genome-wide transcriptome analyses using oligonucleotide arrays. We demonstrate here by both microarrays and Q-PCR that the globin mRNA depletion method resulted in 55-65 fold reduction in globin transcripts in whole blood collected from healthy volunteers and sickle-cell disease patients. This led to an improvement in microarray data quality with increased detection rate of expressed genes and improved overlap with the expression signatures of isolated peripheral blood mononuclear (PBMC) preparations. The differentially modulated genes from the globin depleted samples had a higher correlation coefficient to the 112 genes identified to be significantly altered in our previous study on sickle-cell disease using PBMC preparations. Additionally, the analysis of differences between the whole blood transcriptome and PBMC transcriptome reveals important erythrocyte genes that participate in sickle-cell pathogenesis and compensation. The combination of globin mRNA reduction after whole-blood RNA stabilization represents a robust clinical research methodology for the discovery of biomarkers for hematologic diseases and in multicenter clinical trials investigating a wide range of nonhematologic disorders where fractionation of cell types is impracticable.
Characterization of whole blood gene expression profiles as a sequel to globin mRNA reduction in patients with sickle cell disease.
Specimen part, Subject
View SamplesEmbryonic chicken telencephalon nuclei were isolated for RNAseq to identify transcripts differentially expressed across different brain regions.
Neocortical Association Cell Types in the Forebrain of Birds and Alligators.
Sex, Specimen part
View SamplesThe effects of phosphate starvation in Arabidopsis thaliana (L.) plants were compared in plants grown in liquid MS medium transferred in low or high Pi and in plants grown vertically in petri dishes during 10 days. In the transfer experiments, 2 treatments were analysed for evaluating the short-(3, 6 and 12 h pooled) and medium-(1 and 2 d pooled) term effects of Pi deficiency on the gene expression. Since some Arabidopsis genes are regulated by diurnal rhythm and circadian clocks, plantlets were harvested separately at the beginning and at the end of the photoperiod and pooled. In the long term experiment, leaves and roots were sampled separately after 10 days. Triplicates were analysed for each experiment.
A genome-wide transcriptional analysis using Arabidopsis thaliana Affymetrix gene chips determined plant responses to phosphate deprivation.
Specimen part, Subject
View SamplesThe ER stress inducing agent Thapsigargin (TG) and/or the cytoprotective agent Salubrinal were applied to lymphoblastoid cell lines. TG induced lytic replication as well as a distinct pattern of gene expression changes. This study was designed to identify host genes mediating lytic replication secondary to ER stress.
Endoplasmic reticulum stress causes EBV lytic replication.
Specimen part, Treatment, Time
View SamplesDifferentiation of naive CD8 T cells into cytotoxic effector cells requires three distinct signals- antigen (signal 1), costimulation -B7-1 (signal 2) and cytokine, either interleukin-12 or interferon-a/b (signal 3). Interaction of naive CD8 T cells with antigen and B7-1 programs cell division and proliferation whereas the presence of cytokines- IL-12 or IFNa/b promote survival, differentiation and memory establishment. In the absence of signal 3, the cells interacting with antigen/B7-1 undergo tolerance induction. The objective of this study was to elucidate the mechanisms how the provision of signal 3 promotes differentiation and averts tolerance induction in CD8 T cells. Trichostatin A is a pharmacological agent that inhibits histone deacetylase activity, hence regulating chromatin structure and gene expression and differentiation in many cell types. Gene signature profiles of IL-12, IFNa/b and trichostatin A stimulated cells were compared to elucidate the molecular mechanisms of gene regulation.
Gene regulation and chromatin remodeling by IL-12 and type I IFN in programming for CD8 T cell effector function and memory.
Age, Specimen part, Time
View SamplesSomatic mutation in the X-linked phosphatidylinositol glycan class A (PIG-A) gene causes glycosylphosphatidylinositol (GPI) anchor deficiency in humans with Paroxysmal Nocturnal Hemoglobinuria (PNH). Clinically, patients with PNH have intravascular hemolysis, venous thrombosis and bone marrow failure. We produced a conditional Pig-a knock-out mouse model specifically inactivating the Pig-a gene in hematopoietic cells to study the role of PIG-A deficiency in PNH pathophysiology. We used Affymetrix Mouse Genome 430 2.0 chips to investigate the gene expression pattern in the mouse model of targeted Pig-a deletion.
Phenotypic and functional characterization of a mouse model of targeted Pig-a deletion in hematopoietic cells.
No sample metadata fields
View SamplesHematopoietic differentiation is strictly regulated by complex network of transcription factors that are controlled by ligands binding to cell surface receptors. Disruptions of the intricate sequences of transcriptional activation and suppression of multiple genes cause hematological diseases, such as leukemias, myelodysplastic syndromes or myeloproliferative syndromes. From a clinical standpoint, deciphering the pattern of gene expression during hematopoiesis may help unravel disease-specific mechanisms in hematopoietic malignancies. Herein, we describe a human in vitro hematopoietic model system where lineage specific differentiation of CD34+ cells was accomplished using specific cytokines. Microarray and RNAseq based whole transcriptome and exome analysis was performed on the differentiated erythropoietic, granulopoietic and megakaryopoietic cells to delineate changes in expression of whole transcripts and exons. Analysis on the Human 1.0 ST exon arrays indicated differential expression of 172 genes (P< 0.0000001) and significant splicing of 86 genes during differentiation. Pathway analysis identified these genes to be involved in Rac/RhoA signaling, Wnt/B-catenin signaling and alanine/aspartate metabolism. Comparison of the microarray data to next generation RNAseq analysis during erythroid differentiation demonstrated a high degree of correlation in gene (R= 0.72) and exon (R=0. 62) expression. Our data provides a molecular portrait of events that regulate differentiation of hematopoietic cells. Knowledge of molecular processes by which the cells acquire their cell specific fate would be beneficial in developing cell-based therapies for human diseases.
Transcriptome profiling and sequencing of differentiated human hematopoietic stem cells reveal lineage-specific expression and alternative splicing of genes.
Specimen part
View SamplesAging is associated with mitochondrial dysfunction and insulin resistance. We conducted a study to determine the role of long-term vigorous endurance exercise on age-related changes in insulin sensitivity and various indices of mitochondrial functions.
Endurance exercise as a countermeasure for aging.
No sample metadata fields
View Samples