A detailed knowledge of the mechanisms underlying brain aging is fundamental to understand its functional decline and the baseline upon which brain pathologies superimpose. Endogenous protective mechanisms must contribute to the adaptability and plasticity still present in the healthy aged brain. Apolipoprotein D (ApoD) is one of the few genes with a consistent and evolutionarily conserved up-regulation in the aged brain. ApoD protecting roles upon stress or injury are well known, but a study of the effects of ApoD expression in the normal aging process is still missing. Using an ApoD-knockout mouse we analyze the effects of ApoD on factors contributing to the functional maintenance of the aged brain. We focused our cellular and molecular analyses in cortex and hippocampus at an age representing the onset of senescence where mortality risks are below 25%, avoiding bias towards long-lived animals. Lack of ApoD causes a prematurely aged brain without altering lifespan. Age-dependent hyperkinesia and memory deficits are accompanied by differential molecular effects in cortex and hippocampus. Transcriptome analyses reveal distinct effects of ApoD loss on the molecular age-dependent patterns of cortex and hippocampus, with different cell-type contributions to age-regulated gene expression. Markers of glial reactivity, proteostasis, and oxidative and inflammatory damage reveal early signs of aging and enhanced brain deterioration in the ApoD-knockout brain. The lack of ApoD results in an age-enhanced significant reduction in neuronal calcium-dependent functionality markers and signs of early reduction of neuronal numbers in the cortex, thus impinging upon parameters clearly differentiating neurodegenerative conditions from healthy brain aging. Our data support the hypothesis that the physiological increased brain expression of ApoD represents a homeostatic anti-aging mechanism.
Aging without Apolipoprotein D: Molecular and cellular modifications in the hippocampus and cortex.
Sex, Age, Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Cell-autonomous sex differences in gene expression in chicken bone marrow-derived macrophages.
Sex, Specimen part
View SamplesTo identify markers associated with inherent cellular sex-identity, we analysed cultured macrophages from male and female chick embryos. We found that male and female macrophages respond differently to stimulation by bacterial lipopolysaccharide and that female macrophages constitutively express higher levels of interferon target genes than male macrophages. To determine whether these differences resulted from the actions of gonadal hormones, we induced gonadal sex-reversal to alter the hormonal environment of the developing chick and analysed different tissues and macrophages from male and female embryos.
Cell-autonomous sex differences in gene expression in chicken bone marrow-derived macrophages.
Sex, Specimen part
View SamplesTo identify markers associated with inherent cellular sex-identity, we analysed macrophages from newly-hatched chicks. We found that male and female macrophages respond differently to stimulation by bacterial lipopolysaccharide and that female macrophages constitutively express higher levels of interferon target genes than male macrophages.
Cell-autonomous sex differences in gene expression in chicken bone marrow-derived macrophages.
Sex, Specimen part
View SamplesConsidering the numerous complex and different pathological mechanisms involved in Alzheimers disease (AD) progression, treatments targeting a single cause may lead to limited benefits. The goal of this study was the identification of a novel mode of action for this unmet need. Pharmacological tool compounds: suberoylanilide hydroxamic acid (SAHA) and tadalafil, targeting histone deacetylases (HDAC) and phosphodiesterase 5 (PDE5) respectively, were utilized simultaneously for in-vitro and in-vivo Proof-of-Concept (PoC). A synergistic effect was observed in the amelioration of AD signs using the combination therapy in Tg2576 mice. Finally, a therapeutic agent, CM-414, inhibiting simultaneously HDAC2/6 and PDE5 was generated and tested in Tg2576 mice. CM-414 reversed cognitive impairment, reduced amyloid and tau pathology, and rescued dendritic spine density loss in the hippocampus in AD mice. Importantly, the effect obtained was present after a 4-weeks wash-out period.
Concomitant histone deacetylase and phosphodiesterase 5 inhibition synergistically prevents the disruption in synaptic plasticity and it reverses cognitive impairment in a mouse model of Alzheimer's disease.
Specimen part
View SamplesSubclassification of lymphoid neoplasms is often based on the presumed cell of origin based on T and B progenitor gene expression and the effect of cell lineage on influencing functional characteristics such as aggression and self-renewal capacity is largely unknown, accounted for in part, by lack of experimental models to address these questions. Here, we have used transgenic zebrafish to create the first models of Myc-induced B-ALL and mixed phenotypic B/T-ALL, opening new avenues for studying the these leukemias in the zebrafish. Our work has utilized syngeneic strain zebrafish, limiting dilution cell transplantation, and the widely reported rag2-Myc transgenic model to provide new understanding of how strain differences can underlie leukemia onset in the zebrafish model. Even more importantly, our work now for the first time, has allowed assessment of cell lineage on dictating aggression and leukemia stem cell frequency independent of the underlying oncogenic driver. In total, our work uncoveres that T-ALLs are more aggressive and have higher numbers of leukemia stem cells when compared with B-ALL and mixed phenotypic ALL. Furthermore, analysis of our biphenotypic B/T-ALL suggests that B cell pathways lock cells in less aggressive and lower stem cell fates and are dominant in regulating these processes when T cell pathways are co-regulated within ALL cells. Overall design: The goal of our study is to determine the transcriptional profiles of high and low self-renewing capacity tumors. 20 samples total: 11 unique samples (9 samples with biological replicates), 6 high self-renewing tumors (>1% cells could initiate leukemia) and 5 low self-renewing tumors (<1% of cells could initiate leukemia).
Cell of origin dictates aggression and stem cell number in acute lymphoblastic leukemia.
No sample metadata fields
View SamplesRecent pre-clinical and clinical evidences indicate that hematopoietic stem and progenitor cells (HSPCs) and/or their progeny can serve as vehicles for therapeutic molecule delivery across the blood brain barrier by contributing to the turnover of myeloid cell populations in the brain. However, the differentiation and functional characteristics of the cells reconstituted after transplantation are still to be determined, and in particular whether bona fide microglia could be reconstituted by the donor cell progeny post-transplant to be assessed. We here firstly demonstrate that HSPC transplantation can generate transcriptionally-dependable new microglia through a stepwise process reminiscent of physiological post-natal microglia maturation. Hematopoietic cells able to generate new microglia upon transplantation into myeloablated recipients are retained within human and murine long-term hematopoietic stem cells (HSCs). Similar transcriptionally dependable new microglia cells can also be generated by intra-cerebral ventricular delivery of HSPCs. Importantly, this novel route is associated to a clinically relevant faster and more widespread microglia replacement compared to systemic HSPC injection. Overall, this work supports the relevance and feasibility of employing HSPCs for renewing brain myeloid and microglia cells with new populations endowed with the ability to exert therapeutic effects in the central nervous system, and identifies novel modalities, such as transplantation of enriched stem cell fractions and direct brain delivery of HSPCs, for increasing the actual contribution of the transplanted cells to microgliosis and their therapeutic activity. Overall design: mRNA profiles of µ and TAµ myeloid brain populations were obtained in triplicate mice of Adult control, P10 control and Adult BU-treated mice after GFP Lin-transplantation (both µ and TAµ populations)
Intracerebroventricular delivery of hematopoietic progenitors results in rapid and robust engraftment of microglia-like cells.
Specimen part, Cell line, Subject
View SamplesComprehensive knowledge of the dynamic changes in the cardiac transciptome can inform disease mechanism. Previous transcriptome profiling studies on heart failure rely on either microarray or RNA-Seq with low coverage, leaving a large portion of the transcriptome unexplored. Additionally, previous studies only examined two end stages of the disease, onset and late-stage heart failure. Profile of the transcriptome in the middle stage of disease progression can reveal critical molecular events underlying disease transition. Towards these goals, we conducted a multi-factorial RNA-Seq experiment, comparing the dynamic changes in the transcriptome of two murine models of heart failure, pressure overload and loss of mitochondrial complex I. Our data represents the deepest transcriptome coverage to date, covering onset, progression, and late stage of the disease. We found extensive differences in the expression magnitude and dynamics of the transciptomes in different heart failure models. In addition, such differences are associated with progressive worsening of cardiac physiology. Our analysis revealed that mitochondrial dysfunction combined with stress leads to increased number of differentially expressed long intergenic noncoding RNAs, including a recently identified lincRNA that is a master regulator of the cardiac lineage during development. Overall design: Cardiac tissues were cleaned with PBS and harvested at 1, 2, 4, and 8 weeks after surgeries by freezing in liquid nitrogen. Cardiac RNA profiles of wild type (WT) and ndufs4H-/- mice after surgeries were generated by deep sequencing at 4 time points, in quadruplicate, using Illumina HiSeq2000. The three factors of the data are genetic (WT vs. ndufs4H-/-), environmental stress (trans-aortic constriction vs. Sham controls), and time (Week 1, Week 2, Week 4 and Week 8). Thus, there are 16 samples in total and each sample has 4 replicates.
Revealing Pathway Dynamics in Heart Diseases by Analyzing Multiple Differential Networks.
No sample metadata fields
View SamplesNuclear Protein 1 (Nupr1) is a major actor of the cell stress response required for KrasG12D-driven formation of pancreatic intraepithelial neoplastic (PanINs) lesions in mice. We investigated the impact of Nupr1-depletion on the development and biology of murin pancreatic adenocarcinomas (PDAC) in the Pdx1-cre;LSL-KrasG12D;Ink4a/Arffl/fl (KIC) mice. We found that only one half of Nupr1-deficient mice developed PDAC. This is related to increased caspase 3 activity and low IER3 expression in Nupr1-deficient;KIC in the pancreas. Moreover, when Nupr1-deficient;KIC mice do develop PDAC, tumors present with impaired epithelial-to-mesenchymal transition (EMT). Transcriptoma analysis revealed that Nupr1-deficient and Nupr1wt;KIC PDACs presented enrichment of gene signatures of the human classical- and quasi-mesenchymal (QM)-PDAC respectively. Moreover, Nupr1-deficient;KIC PDACs shared with human classical-PDACs overexpression of Kras-activation genes. In addition, cells derived from Nupr1-deficient;KIC PDACs formed fewer microspheres in vitro compared to Nupr1wt;KIC cells, indicative of stemness impairment in the absence of Nupr1. Finally, we found that Nupr1-deficient;KIC cells were more sensitive to some anticancer drugs than their Nupr1wt counterpart. Hence, this study establishes the pivotal role of Nupr1 in PDAC progression after PanIN and in PDAC EMT in vivo, with an impact in PDAC cell stemness. As a consequence, according to absence or presence of Nupr1, KIC mice develop tumors that phenocopy human classical- or QM-PDAC, respectively, thus becoming attractive models for preclinical drug trials.
Genetic inactivation of Nupr1 acts as a dominant suppressor event in a two-hit model of pancreatic carcinogenesis.
Specimen part
View SamplesCurrent expression profiling methods use RNA from hundreds of thousands or thousands cells. Many fields of biology can not use microarrays due to the nature of the biological systems used that are formed by hundreds or dozens of cells. Here we present a method that can handle RNA amount limitation and gives gene expression profiles from as little as 10 cells. We first validate the method hybridizing amplified RNA from MAQC samples A and B. To do that, 25 ng or 100 pg were used and expression profiles obtained as good as when compared to Affymetrix's chemistry for amplification and labeling. The same experiment was done but using sorted cells from two comercial cell lines (SW620 and SW480) obtaining the same differential expression profiling from 2000 cells or 10 cells. The central step of the method is Whole Transcriptome Amplification (WTA) from Sigma that allows the amplification of very small amounts of RNA as starting material.
Accurate expression profiling of very small cell populations.
Cell line
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