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 SamplesThe aim of this work was to produce a reproducible molecular signature of human muscle responses to resistance training and examine how such a profile relates to new and established exercise adaptation gene networks.
Molecular networks of human muscle adaptation to exercise and age.
Age, Specimen part, Subject, Time
View SamplesThe overall objective of the heritage project is to study the role of the genotype in cardiovascular,metabolic and hormonal responses to aerobic exercise training and the contribution of regular exercise to changes in several cardiovascular disease and diabetes risk factors.
Molecular networks of human muscle adaptation to exercise and age.
Age, Specimen part, Subject, Time
View SamplesThe mechanisms underlying muscle wasting in cancer patients remain poorly understood, and consequently there remains an unmet clinical need for new biomarkers and treatment strategies.
Suppression of skeletal muscle turnover in cancer cachexia: evidence from the transcriptome in sequential human muscle biopsies.
Sex, Age, Specimen part
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 SamplesBackground: The use of electrical pulses to enhance uptake of molecules into living cells have been used for decades. This technique, often referred to as electroporation, has become an increasingly popular method to enhance in vivo DNA delivery for both gene. therapy applications as well as for delivery of vaccines against both infectious diseases and cancer. In vivo electrovaccination is currently being investigated in several clinical trials, including DNA delivery to healthy volunteers. However, the mode of action at molecular level is not yet fully understood.
Skin electroporation: effects on transgene expression, DNA persistence and local tissue environment.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
A transcriptional map of the impact of endurance exercise training on skeletal muscle phenotype.
Sex
View SamplesThe molecular pathways which are activated and contribute to physiological remodeling of skeletal muscle in response to endurance exercise have not been fully characterized. We previously reported that ~800 gene transcripts are regulated following 6 weeks of supervised endurance training in young sedentary males, referred to as the training responsive transcriptome (TRT). Here we utilized this database together with data on biological variation in muscle adaptation to aerobic endurance training in both humans and a novel out-bred rodent model to study the potential regulatory molecules that coordinate this complex network of genes. We identified three DNA sequences representing RUNX1, SOX9, and PAX3 transcription factor binding sites as over-represented in the TRT. In turn, miRNA profiling indicated that several miRNAs targeting RUNX1, SOX9 and PAX3 were down-regulated by endurance training. The TRT was then examined by contrasting subjects who demonstrated the least vs. the greatest improvement in aerobic capacity (low vs. high responders), and at least 100 of the 800 TRT genes were differentially regulated, thus suggesting regulation of these genes may be important for improving aerobic capacity. In high responders, pro-angiogenic and tissue developmental networks emerged as key candidates for coordinating tissue aerobic adaptation. Beyond RNA level validation there were several DNA variants that associated with VO(2)max trainability in the HERITAGE Family Study but these did not pass conservative Bonferroni adjustment. In addition, in a rat model selected across 10 generations for high aerobic training responsiveness, we found that both the TRT and a homologous subset of the human high responder genes were regulated to a greater degree in high responder rodent skeletal muscle. This analysis provides a comprehensive map of the transcriptomic features important for aerobic exercise-induced improvements in maximal oxygen consumption.
A transcriptional map of the impact of endurance exercise training on skeletal muscle phenotype.
Sex
View SamplesAffymetrix Mouse Gene 1.0 ST Array profiles were generated from acticular cartilage derived from CBA and Str/ort mice at three ages (8W, 18W, 40W), corresponding to stages prior to, at and late after natural osteoarthritis (OA) onset in OA-prone Str/ort mice.
Time-series transcriptional profiling yields new perspectives on susceptibility to murine osteoarthritis.
Age, Specimen part
View Samples