Acute quadriplegic myopathy (AQM) or critical illness myopathy (CIM) is frequently observed in intensive care unit (ICU) patients. In order to elucidate duration-dependent effects of the ICU intervention on molecular and functional networks that control the muscle wasting and weakness in AQM, gene expression profile was analyzed at time points varying from 6 hours to 14 days in a unique experimental rat model mimicking ICU conditions, i.e., post-synaptically paralyzed, mechanically ventilated and extensively monitored animals.
Muscle wasting and the temporal gene expression pattern in a novel rat intensive care unit model.
Sex, Specimen part, Disease, Disease stage
View SamplesCritically ill intensive care unit (ICU) patients commonly develop severe muscle wasting and impaired muscle function, leading to delayed recovery, with subsequent increased morbidity and financial costs, and decrease quality of life of survivors. Acute Quadriplegic Myopathy (AQM) is one of the most common neuromuscular disorders associated with ICU-acquired muscle weakness. Although there are no available treatments for the ICU-acquired muscle weakness, it has been demonstrated that early mobilization can improve its prognosis and functional outcomes. This study aims at improving our understanding of the effects of passive mechanical loading on skeletal muscle structure and function by using a unique experimental rat ICU model allowing analyses of the temporal sequence of changes in mechanically ventilated and pharmacologically paralyzed animals at durations varying from 6 h to 14 days. Results show that passive mechanical loading alleviated the muscle wasting and the loss of force-generation associated with the ICU intervention, resulting in a doubling of the functional capacity of the loaded vs. unloaded muscles after a 2-week ICU intervention. We demonstrated that the improved maintenance of muscle structure and function is likely a consequence of a reduced oxidative stress, and a reduced loss of the molecular motor protein myosin. A complex temporal gene expression pattern, delineated by microarray analysis, was observed with loading-induced changes in transcript levels of sarcomeric proteins, muscle developmental processes, stress response, ECM/cell adhesion proteins and metabolism. Thus, the results from this study show that passive mechanical loading alleviates the severe negative consequences on muscle structure and function associated with mechanical silencing in ICU patients, strongly supporting early and intense physical therapy in immobilized ICU patients.
Sparing of muscle mass and function by passive loading in an experimental intensive care unit model.
Sex, Specimen part, Time
View SamplesDiamond-Blackfan anemia (DBA) is characterized by anemia and cancer susceptibility, and is caused by mutations in ribosomal genes, including Rpl11. Here, we report that Rpl11-heterozygous embryos are not viable, and homozygous deletion of Rpl11 in adult mice results in death within a few weeks, accompanied by bone marrow aplasia and intestinal atrophy. Importantly, deletion of a single Rpl11 allele in adult mice results in anemia associated to decreased erythroid progenitors and defective erythroid maturation. These phenotypes are also present in mice transplanted with inducible heterozygous Rpl11 bone marrow, indicating a cell-autonomous role of RPL11 in erythropoiesis. Additionally, fibroblasts lacking one or both Rpl11 alleles show defective p53 activation upon ribosomal stress or DNA damage. Furthermore, fibroblasts and hematopoietic tissues from heterozygous Rpl11 mice present higher basal cMYC levels. Accordingly, heterozygous Rpl11 mice are highly susceptible to radiation-induced lymphomagenesis. We conclude that Rpl11-deficient mice recapitulate DBA disorder, including cancer predisposition. Overall design: RNAseq profiles of bone marrow hematopoietic progenitors cells from WT (Rpl11+/+:: Tg.UbC-CreERT2) and LOX (Rpl11+/lox::Tb.Ub-CreERT2) mice, n=4 independent animals per genotype
Partial Loss of Rpl11 in Adult Mice Recapitulates Diamond-Blackfan Anemia and Promotes Lymphomagenesis.
Sex, Age, Specimen part, Cell line, Subject
View SamplesUnderstanding the underlying mechanisms of the well-established platelet hyporeactivity in neonates, would be of great relevance for both improving the clinical management of neonates, a population with a higher bleeding risk than adults (especially among sick and preterm infants), and getting new insights onto the regulatory mechanisms of platelet biology. Transcriptome analysis is a useful tool to identify mRNA signature affecting platelet function. However, human fetal/neonatal platelet transcriptome analysis has never been reported. Here, we used, for the first time, mRNA expression array to compare the platelet transcriptome changes during development. Microarray analysis was performed in pure platelet RNA obtained from adult and cord blood, using the same platform in two independent laboratories.
Comprehensive comparison of neonate and adult human platelet transcriptomes.
Specimen part
View SamplesDespite known age-related DNA methylation (aDNAm) changes in breast tumors, little is known about aDNAm in normal breast tissues. Breast tissues from a cross-sectional study of 121 cancer-free women, were assayed for genome-wide DNA methylation. mRNA expression was assayed by microarray technology. Analysis of covariance was used to identify aDNAms. Altered methylation was correlated with expression of the corresponding gene and with DNA methyltransferase protein DNMT3A, assayed by immunohistochemistry. Publically-available TCGA data were used for replication. 1,214 aDNAms were identified; 97% with increased methylation, and all on autosomes. Sites with increased methylation were predominantly in CpG lslands and non-enhancers. aDNAms with decreased methylation were generally located in intergenic regions, non-CpG Islands, and enhancers. Of the aDNAms identified, 650 are known to be involved in cancer, including ESR1 and beta-estradiol responsive genes. Expression of DNMT3A was positively associated with age. Two aDNAms showed significant associations with DNMT3A expression; KRR1 (OR 6.57, 95% CI: 2.51-17.23) and DHRS12 (OR 6.08, 95% CI: 2.33-15.86). A subset of aDNAms co-localized within vulnerable regions for somatic mutations in breast cancer. Expression of C19orf48 was inversely and significantly correlated with its methylation level. In the TCGA dataset, 84% and 64% of the previously identified aDNAms were correlated with age in both normal-adjacent and tumor breast tissues, with differential associations by histological subtype. Given the similarity of findings in the breast tissues of healthy women and breast tumors, and the effects on gene expression, aDNAms may be one pathway for increased breast cancer risk with age.
Landscape of genome-wide age-related DNA methylation in breast tissue.
Age, Race
View SamplesPurpose: The outer blood-retina barrier is established through the coordinated terminal maturation of the retinal pigment epithelium (RPE), fenestrated choroid endothelial cells (ECs) and Bruch’s membrane, a highly organized basement membrane that lies between both cell types. Here we study the contribution of choroid ECs to this process by comparing their gene expression profile before (P5) and after (P30) the critical postnatal period when mice acquire mature visual function. Methods: ECs from P5 and P30 mice were labeled in vivo by retro-orbital injection of fluorescently-labeled anti-VE-Cadherin. After 10 minutes, mice were euthanized, eyeballs were enucleated and the anterior segment was discarded. After removal of the neural retina, RPE/choroid was mechanically dissected from the sclera and digested. ECs were isolated by flow cytometry and processed immediately for RNA extraction. Results: Transcriptome analyses show that whereas P5 choroid EC transcriptome is preferentially enriched in cell cycle- and chromosome-related transcripts, reflecting an immature phenotype, the transcriptome of adult (P30) choroid ECs is enriched in genes encoding proteins involved in ‘biological adhesion’, including a variety of extracellular matrix (ECM)-related genes. Conclusion: these results strongly suggest that mature choroid ECs actively participate in extracellular matrix assembly and regulation. Overall design: Transcriptome of choroid ECs isolated from P5 and P30 mice (3 independent isolations, 7 animals per isolation) was determined using the Illumina HiSeq2000 platform. Upon quality control using FastQC, raw reads were aligned to the mouse genome (mm9) using TopHat with default parameters. CuffLinks with GC and upper quartile normalization was then used to calculate normalized expression levels.
Concerted regulation of retinal pigment epithelium basement membrane and barrier function by angiocrine factors.
Specimen part, Cell line, Subject
View SamplesSenescent cells accumulate in many ageing-associated diseases such as pulmonary fibrosis, and targeting these cells has recently emerged as a promising therapeutic approach. Here, we take advantage of the high ß-galactosidase activity of senescent cells to design a targeted drug delivery system based on the encapsulation of drugs with galacto-oligosaccharides (GalNP beads). In this experiment we show that gal-encapsulated rhodamine target senescent cells in the context of pulmonary fibrosis in mice. Overall design: 8- to 10-week-old C57BL/6 wild-type mice were intratracheally inoculated with bleomycin at 1.5 U/kg of body weight. Two weeks later mice were i.v. injected with 200 µl of a solution of GalNP beads loaded with rhodamine [GalNP(rho)] at 4 mg/ml, equivalent to 1 mg/kg of deliverable rhodamine. 6 hours later mice were sacrificed and lung cells were analysed by flow cytometry and sorted into Rho+ or Rho- cells, all CD45-CD31-.
A versatile drug delivery system targeting senescent cells.
Specimen part, Cell line, Subject
View SamplesWe have reported previously that when chromosome Y (chrY) from the mouse strain C57BL/6J (abbreviated as B) was substituted for that of A/J mice (ChrY<A>), cardiomyocytes from the resulting 'chromosome substitution' C57BL/6J-chrY<A> strain (abbreviated as B.Y) were smaller than that of their C57BL/6J counterparts. In reverse, when chrY<A> from A/J mice was substituted for that of chrY<B>, cardiomyocytes from the resulting A/J-chrY<C57> strain were larger than in their A/J counterparts. We further used these strains (B and the consomic B.Y) to test whether the origin of chrY could also be linked to differences in the profile of gene expression in their cardiac left ventricles in adult mice where either sham surgery (intact animals) or castration has been performed at 3-4 weeks of age..
Chromosome Y variants from different inbred mouse strains are linked to differences in the morphologic and molecular responses of cardiac cells to postpubertal testosterone.
Sex
View SamplesMutants in the Drosophila gene lethal (3) malignant brain tumor cause malignant growth in the larval brain. This data shows the changes in gene expression profile associated to mutations in l(3)mbt, both in situ in third instar larval brains and in tumors cultured for 1 5 and 10 (T1, T5, T10) rounds of allograft culture
Ectopic expression of germline genes drives malignant brain tumor growth in Drosophila.
No sample metadata fields
View SamplesPurpose: The goal of this study is to compare the transcriptome profilling (RNA-seq) of inflorescences infected with tobacco ratle virus (TRV) to mock inoculated inflorescences (negative controls), in Arabidopsis plants Methods: Inflorescences of systemically TRV infected or mock-inoculated plants were collected from more than 40 independent Arabidopsis plants, at 14 days post-inoculation (dpi). TRV and mock mRNA profiles were generated by deep sequencing by Illumina HiSeq 2000. The sequence reads that passed quality filters (SOAPnuke) were analysed by Burrows-Wheeler (BWA) followed by ANOVA (ANOVA) and TopHat followed by Cufflinks. Genes and isoforms were quantified by RSEM sofware package. qRT-PCR validation was performed using TaqMan and SYBR Green assays. Results: Here we report a significant repression of DNA methylation genes in inflorescences of Arabidopsis plants infected with Tobacco rattle virus (TRV) that coincides with dynamic changes in methylation at the whole genome level. Arabidopsis mutants deficient in DNA methylation were more resistant to this virus in early colonized tissues but more susceptible at later time points of infection, indicating that DNA methylation was critical to control both proliferation and antiviral defense. We found that TRV interference with DNA methylation leads to changes in the methylation and trancriptional status of transposable elements (TEs), including TEs located in the promoter of disease resistance genes that were significantly repressed in plants exposed to TRV. Activation of both TEs and their nearby disease resistance genes was altered in a range of hypo- and hyper-methylated Arabidopsis mutants, indicating that perturbations in DNA methylation contributes to modulate their expression in infected plants. Conclussion: Our study showed that TRV interferes with DNA methylation to alter the transcriptional silencing of TEs, which in turn compromises the expression of neighboring disease resistance genes. Overall design: TRV and mock mRNA profiles were generated from Arabidopsis inflorescences by deep sequencing with Illumina HiSeq 2000.
Crosstalk between epigenetic silencing and infection by tobacco rattle virus in Arabidopsis.
Specimen part, Subject
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