Inherent depot- and age-dependent preadipocyte characteristics may contribute to age-related fat redistribution. Both aging and depot origin affect preadipocyte replication and adipogenesis. To define responsible mechanisms, we analyzed genome-wide expression profiles in epididymal (E) and perirenal (P) preadipocytes cultured from young (3 month) and old (30m) rats. Differences between depots were distinct from and more dramatic than those that occur with aging.
Aging, depot origin, and preadipocyte gene expression.
Sex
View SamplesFat tissue was resected during gastric bypass surgery for management of obesity. All subjects had fasted at least 10 hours before surgery. Subjects with malignancies were excluded. No subjects were taking thiazolidinediones or steroids. None had fasting plasma glucose levels over 120 mg/ dl. One half to 10 g of abdominal subcutaneous (external to the fascia superficialis), mesenteric, and greater omental fat were obtained from each subject. The tissue was collected in Hanks balanced salt solution with bicarbonate, penicillin, and gentamicin. Fat tissue was minced and then digested in HBSS containing 1 mg/ml collagenase and 7.5% fetal bovine serum in a 37*C shaking water bath until fragments were no longer visible and the digest had a milky appearance. Digests were filtered and centrifuged at 800xG for 10 min. The digests were treated with an erythrocyte lysis buffer. Cells were plated in 1:1 Dulbeccos modified Eagles medium:Hams F12 that contained 10% fetal bovine serum and antibiotics at a density of 4 x 104 cells/cm2. After 18 hours cultures were trypsinized until 95% of cells were detached (leaving endothelial cells and macrophages behind) and re-plated. Macrophages were rare (less than 5 per 106 cells, as assessed by phase contrast microscopy) in the re-plated cultures, irrespective of fat depot origin. Plating medium was changed every 2 days until confluence. For differentiation, preadipocytes were treated for 30 days with plating medium (without serum) enriched with 100 nM dexamethasone, 500 nM human insulin, 200 pM triiodothyronine, 0.5 *M rosiglitazone, antibiotics, and 540 *M methylisobutylxanthine (removed after 2 days). Higher rosiglitazone and insulin concentrations did not further enhance differentiation. Medium was changed every 2 days. For the final 2 days, differentiation medium was removed and cells were cultured in plating medium without serum. Undifferentiated preadipocytes were maintained in plating medium until confluence, when serum was removed for 2 days. For telomerase-expressing clones, preadipocytes were isolated and when cells had undergone 7 population doublings, they were transduced with a retrovirus containing the plasmid, pBABE-hTERT-Hygro. This vector expresses the human telomerase reverse transcriptase component (hTERT) driven by the Moloney murine leukemia virus long terminal repeat promoter and a hygromycin resistance sequence driven by the SV40 promoter. The 3 abdominal subcutaneous and 3 omental stably transduced, hygromycin-resistant clones capable of achieving confluence fastest were selected from 38 subcutaneous and 42 omental clones. Telomerase activity in these clones was verified using a PCR-based telomere repeat amplification protocol. RNA was isolated from preadipocytes by the Trizol method. RNA samples were labeled using the standard one-cycle Affymetrix GeneChip Eukaryotic Target Labeling Assay for Expression Analysis. Samples were hybridized for 16 hours at 45 C and 60 rpm, washed and stained according to the standard Affymetrix Antibody Amplification for Eukaryotic Targets protocol, and scanned at 488 nm. Images were quantified and linearly scaled using Affymetrix GeneChip Operating Software 1.1 using default analysis settings.
Identification of depot-specific human fat cell progenitors through distinct expression profiles and developmental gene patterns.
No sample metadata fields
View SamplesHistone deacetylase inhibitors are efficacious epigenetic-based therapies for some cancers and neurological disorders; however, these drugs inhibit multiple Hdacs and have detrimental effects on the pre- and post-natal skeleton. To better understand how Hdac inhibitors affect the skeleton, we focused on understanding the role of one of their targets, Hdac3, in endochondral bone formation by deleting it in immature murine chondrocyte micro masses with Adeno-Cre. Hdac3-deficient chondrocytes expressed higher levels of pro-inflammatory and matrix degrading genes (e.g., Il-6, Mmp3, Mmp13, Saa3) and lower levels of genes related to the extracellular matrix production, bone development and ossification (e.g., Acan, Col2a1, Ihh, Col10a1). Histone acetylation was increased in and around genes with elevated expression. Overall design: High Throughput RNA sequencing and Chromatin immunopreciptation sequencing experiments were performed in chondrocyte cultures. Differential analysis was conducted on ChIP-seq and RNA-seq data to identify H3K27Ac profile for up and down regulated genes in Hdac3-deficient murine chondrocytes.
Histone deacetylase 3 supports endochondral bone formation by controlling cytokine signaling and matrix remodeling.
Specimen part, Cell line, Subject
View SamplesIPF (n=20) and control (n=19) samples were obtained through the LTRC and were sequenced on an Illumina HiSeq 2000 following TruSeq RNA Sample Prep Kit v2 library preparation. Overall design: Cross-sectional samples were analyzed. IPF diagnosis was based on American Thoracic Society and European Respiratory Society criteria, and all IPF samples displayed typical patterns of usual interstitial pneumonia. RNA libraries were prepared from 200 ng of high quality total RNA according to the manufacturer’s instructions for the TruSeq RNA Sample Prep Kit v2 (Illumina, San Diego, CA). The concentration and size distribution of TruSeq libraries was determined on an Agilent Bioanalyzer DNA 1000 chip (Santa Clara, CA), and a final quantification, using Qubit fluorometry (Invitrogen, Carlsbad, CA), was conducted to confirm sample concentration. Libraries were loaded onto paired end flow cells at concentrations of 8-10 pM to generate cluster densities of 700,000/mm2 following Illumina’s standard protocol using the Illumina cBot and cBot Paired end cluster kit version 3. The flow cells were sequenced as 51 X 2 paired end reads on an Illumina HiSeq 2000 using TruSeq SBS sequencing kit version 3 and SCS version 1.4.8 data collection software. Base-calling was performed using Illumina’s RTA version 1.12.4.2.
Cellular senescence mediates fibrotic pulmonary disease.
Specimen part, Disease, Disease stage, Subject
View SamplesThe healthspan of mice is enhanced by selectively killing senescent cells using a transgenic suicide gene. Achieving the same using small molecules would have a tremendous impact on quality of life and burden of age-related chronic diseases.
The Achilles' heel of senescent cells: from transcriptome to senolytic drugs.
Specimen part, Subject
View SamplesAgeing is the biggest risk factor to cardiovascular health and is associated with increased incidence of cardiovascular disease. Cellular senescence, a process driven in part by telomere shortening has been implicated in age-related cardiac dysfunction. However, the role of cellular senescence and its underlying mechanisms in slowly dividing/post-mitotic cardiomyocytes is not understood. Overall design: We quantify transcription via high throughput RNA sequencing in young (3 months) and old (20 months) mouse cardiomyocytes.
Length-independent telomere damage drives post-mitotic cardiomyocyte senescence.
Age, Cell line, Subject
View SamplesUnderstanding gene expression profile and transcriptional regulation of healthy adult human hepatocytes
Differentiation in stem/progenitor cells along fetal or adult hepatic stages requires transcriptional regulators independently of oscillations in microRNA expression.
Specimen part, Time
View SamplesActivation of glycolytic genes by HIF-1 is considered critical for metabolic adaptation to hypoxia. We found that HIF-1 also actively suppresses glucose metabolism through the tricarboxylic acid cycle (TCA) by directly trans-activating the gene encoding pyruvate dehydrogenase kinase 1 (PDK1). PDK1 inactivates the TCA cycle enzyme, pyruvate dehydrogenase (PDH), which converts pyruvate to acetyl-CoA. Forced PDK1 expression in hypoxic HIF-1-null cells increases ATP levels, attenuates hypoxic ROS generation and rescues these cells from hypoxia-induced apoptosis. These studies reveal a novel hypoxia-induced metabolic switch that shunts glucose metabolites from the mitochondria to glycolysis to maintain ATP production and to prevent toxic ROS production.
HIF-1-mediated expression of pyruvate dehydrogenase kinase: a metabolic switch required for cellular adaptation to hypoxia.
No sample metadata fields
View SamplesBy comparing HeLa cells lacking ATF7IP or SETDB1 generated through CRISPR/Cas9-mediated gene disruption to wild-type HeLa cells, the goal of the experiment was to determine the effect of loss of the SETDB1•ATF7IP complex on the transcriptome. Overall design: Total RNA-seq of three independent knockout HeLa clones lacking either ATF7IP or SETDB1
ATF7IP-Mediated Stabilization of the Histone Methyltransferase SETDB1 Is Essential for Heterochromatin Formation by the HUSH Complex.
Cell line, Subject
View SamplesAndrogens have been postulated to be important modulators of adipose tissue metabolism and fat cell function. In the present study, we investigated the response of male and female mice retroperitoneal adipose tissue to the non-aromatizable androgen dihydrotestosterone (DHT). Adipose tissue samples were obtained in gonadectomized (GDX) animals treated with vehicle (control group), or injected with 0.1mg DHT at 1, 3, 6, 12, 18 and 24h prior to necropsy. Transcripts which were significantly modulated were considered as androgen-responsive genes. Quantitative real-time RT-PCR was used to confirm results from the microarry analysis in a subset of 46 probe sets in male mice and 98 probe sets in female mice. Using both methods and considering peak time versus control, 74.5% and 61.2% of the modulated genes were confirmed by PCR in males and females, respectively. Four genes were significantly stimulated in a similar manner by DHT in both sexes, namely metallothionein 1 (Mt1), growth arrest and DNA-damage-inducible 45 gamma (Gadd45g), cyclin-dependent kinase inhibitor 1A (Cdkn1a), and fk506-binding protein 5 (Fkbp5). All these genes appear to be associated with a down-regulation of adipocyte differentiation/proliferation and adipogenesis. In conclusion, this study which evaluated the transcriptome response of adipose tissue to DHT in male and female mice suggests that DHT consistently modulates genes involved in the regulation of adipogenesis in retroperitoneal adipose tissue of both male and female animals.
Response of the adipose tissue transcriptome to dihydrotestosterone in mice.
No sample metadata fields
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