This SuperSeries is composed of the SubSeries listed below.
Gene-chip studies of adipogenesis-regulated microRNAs in mouse primary adipocytes and human obesity.
Age, Specimen part
View SamplesAdipose tissue abundance relies partly on the factors that regulate adipogenesis, i.e. proliferation and differentiation of adipocytes. While the transcriptional program that initiates adipogenesis is well-known, the importance of microRNAs in adipogenesis is less well studied. We thus set out to investigate whether miRNAs would be actively modulated during adipogenesis and obesity. Several models exist to study adipogenesis in vitro, of which the cell line 3T3-L1 is probably the most well known, albeit not the most physiologically appropriate. We used a microarray strategy to provide a global profile of miRNAs in brown and white primary murine adipocytes (prior to and following differentiation) and evaluated the similarity of the responses to non-primary cell models, through literature data-mining. We found 65 miRNAs regulated during in vitro adipogenesis in primary adipocytes. When we compared our primary adipocyte profiles with those of cell lines reported in the literature, we found a high degree of difference in adipogenesis-regulated miRNAs. We evaluated the expression of 10 of our adipogenesis-regulated miRNAs using real-time qPCR and then selected 5 miRNAs that showed robust expression levels and profiled these by qPCR in subcutaneous adipose tissue of 20 humans with a range of body mass indices (BMI, range=21-48). Of the miRNAs tested, mir-21 was both highly expressed in human adipose tissue and positively correlated with BMI (R2=0.49, p<0.001). In conclusion, we provide the preliminary analysis of miRNAs important for primary cell in vitro adipogenesis and find that the inflammation-associated miRNA, mir-21, is up-regulated in subcutaneous adipose tissue in human obesity.
Gene-chip studies of adipogenesis-regulated microRNAs in mouse primary adipocytes and human obesity.
Age
View SamplesSeptic patients treated in the intensive care unit (ICU) often develop multiple organ failure including persistent skeletal muscle dysfunction which results in the patients protracted recovery process. We have demonstrated that muscle mitochondrial enzyme activities are impaired in septic ICU patients resulting in decreased cellular energy which will interfere with muscle function and metabolism. Here we use detailed phenotyping and genomics to elucidate mechanisms leading to these impairments. Methodology/Principle Findings Utilising biopsy material from seventeen patients and ten age-matched controls we demonstrate that neither mitochondrial in vivo protein synthesis nor expression of mitochondrial genes are compromised. Indeed, there was partial activation of the mitochondrial biogenesis pathway involving NRF2?/GABP and its target genes TFAM, TFB1M and TFB2M yet clearly this failed to maintain mitochondrial function. We therefore utilised transcript profiling and pathway analysis of ICU patient skeletal muscle to generate insight into the molecular defects driving loss of muscle function and metabolic homeostasis. Gene ontology analysis of Affymetrix analysis demonstrated substantial loss of muscle specific genes, a global oxidative stress response related to most probably cytokine signalling, altered insulin related signalling and a substantial overlap between patients and muscle wasting/inflammatory animal models. MicroRNA 21 processing appeared defective suggesting that post-transcriptional protein synthesis regulation is altered by disruption of tissue microRNA expression. Finally, we were able to demonstrate that the phenotype of skeletal muscle in ICU patients is not merely one of inactivity, it appears to be an actively remodelling tissue, influenced by several mediators, all of which may be open to manipulation with the aim to improve clinical outcome. Conclusions/Significance This first combined protein and transcriptome based analysis of human skeletal muscle obtained from septic patients demonstrated that losses of mitochondria and muscle mass are accompanied by sustained protein synthesis (anabolic process) while dysregulation of transcription programmes appears to fail to compensate for increased damage and proteolysis. Our analysis identified both validated and novel clinically tractable targets to manipulate these failing processes and pursuit of these could lead to new potential treatments.
Dysregulation of mitochondrial dynamics and the muscle transcriptome in ICU patients suffering from sepsis induced multiple organ failure.
Sex
View SamplesProliferative cells isolated from the adult human peripheral retina only transiently upregulate key retinal markers upon induced differentiation.
Proliferative Cells Isolated from the Adult Human Peripheral Retina only Transiently Upregulate Key Retinal Markers upon Induced Differentiation.
Specimen part, Time
View SamplesFrom over 300 patients two groups were selected which had prostate tumors with either well differentiated (WD) or poorly differentiated (PD) after radical Prostatectomy. The PD group had Gleason score 8-9, seminal vesicle invasion, and poorly differentiated tumor cells; the WD group had Gleason score 6-7, no seminal vesicle invasion, and well to moderately differentiated tumor cells. LCM compatible specimens were selected from age and race (Caucasians) matched PD or WD patients with no family history of CaP. Matching normal epithelal cells were also selected for the analysis.
Elevated osteonectin/SPARC expression in primary prostate cancer predicts metastatic progression.
Specimen part
View SamplesAttainment of a brown adipocyte cell phenotype in white adipocytes, with their abundant mitochondria and increased energy expenditure potential, is a legitimate strategy for combating obesity. The unique transcriptional regulators of the primary brown adipocyte phenotype are unknown, limiting our ability to promote brown adipogenesis over white. In the present work, we used microarray analysis strategies to study primary preadipocytes, and we made the striking discovery that brown preadipocytes demonstrate a myogenic transcriptional signature, whereas both brown and white primary preadipocytes demonstrate signatures distinct from those found in immortalized adipogenic models. We found a plausible SIRT1-related transcriptional signature during brown adipocyte differentiation that may contribute to silencing the myogenic signature. In contrast to brown preadipocytes or skeletal muscle cells, white preadipocytes express Tcf21, a transcription factor that has been shown to suppress myogenesis and nuclear receptor activity. In addition, we identified a number of developmental genes that are differentially expressed between brown and white preadipocytes and that have recently been implicated in human obesity. The interlinkage between the myocyte and the brown preadipocyte confirms the distinct origin for brown versus white adipose tissue and also represents a plausible explanation as to why brown adipocytes ultimately specialize in lipid catabolism rather than storage, much like oxidative skeletal muscle tissue.
Myogenic gene expression signature establishes that brown and white adipocytes originate from distinct cell lineages.
No sample metadata fields
View SamplesCold triggers VEGF dependent but hypoxia independent angiogenesis in adipose tissues and anti-VEGF agents modulate adipose metabolism
Hypoxia-independent angiogenesis in adipose tissues during cold acclimation.
Sex
View SamplesThe Toll-like receptor 4 (TLR4) pathway is important for tumor-initiating cells. We used microarrays to obtain gene profiling data in order to increase understanding of the pathways.
Reciprocal regulation by TLR4 and TGF-β in tumor-initiating stem-like cells.
Sex, Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
<i>APOL1</i> Renal-Risk Variants Induce Mitochondrial Dysfunction.
Specimen part
View SamplesTo assess differential gene expression by APOL1 renal-risk (2 risk alleles) vs. non-risk (G0G0) genotypes in primary proximal tubule cells (PTCs), global gene expression (mRNA) levels were examined on Affymetrix HTA 2.0 arrays in primary PTCs cultured from non-diseased kidney in African Americans without CKD who underwent nephrectomy for localized renal cell carcinoma.
<i>APOL1</i> Renal-Risk Variants Induce Mitochondrial Dysfunction.
Specimen part
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