Glyphosate-based herbicides are the major pesticides used worldwide. There is an intense debate on the estrogenic effects of their ingredients. We have compared the estrogenic effects of glyphosate (the active principle), polyethoxylated tallowamine (a co-formulant), and a commercial formulations containing different co-formulants to those of estradiol and bisphenol A in the MCF-7 human breast cancer cell line. The gene expression profiles were determined using the Affymetrix Human Transcriptome 2.0 Array.
Evaluation of estrogen receptor alpha activation by glyphosate-based herbicide constituents.
Cell line, Treatment
View SamplesSomatic stem cells mediate tissue maintenance for the lifetime of an organism. Despite the well-established longevity that is a prerequisite for such function, accumulating data argue for compromised stem cell function with age. Identifying the mechanisms underlying age-dependent stem cell dysfunction is therefore key to understand the aging process.
Accumulating mitochondrial DNA mutations drive premature hematopoietic aging phenotypes distinct from physiological stem cell aging.
Sex, Age, Specimen part
View SamplesAging of hematopoietic stem cells (HSCs) leads to several functional changes, including alterations affecting self-renewal and differentiation. While it is well established that many of the age-induced changes are intrinsic to HSCs, less is known about the stability of this state. Here, we entertained the hypothesis that HSC aging is driven by the acquisition of permanent genetic mutations. To examine this issue at a functional level in vivo, we applied induced pluripotent stem (iPS) cell reprogramming of aged hematopoietic progenitors and allowed the resulting aged-derived iPS cells to reform hematopoiesis via blastocyst complementation. Next, we functionally characterized iPS-derived HSCs in primary chimeras and following the transplantation of 're-differentiated' HSCs into new hosts; the gold standard to assess HSC function. Our data demonstrate remarkably similar functional properties of iPS-derived and endogenous blastocyst-derived HSCs, despite the extensive chronological and proliferative age of the former. Our results therefore favor a model in which an underlying, but reversible, epigenetic component is a hallmark of HSC aging rather than being driven by an increased DNA mutation burden.
An epigenetic component of hematopoietic stem cell aging amenable to reprogramming into a young state.
Specimen part
View SamplesGenome wide RNA-seq from pGM and HSCs in response to expression of the MLL-ENL fusion gene Overall design: Examination of mRNA abundance in two cell types with or without induction of the MLL-ENL fusion gene (following 48h of culture)
Hematopoietic stem cells are intrinsically protected against MLL-ENL-mediated transformation.
No sample metadata fields
View SamplesWe developed a novel culture system to obtain multilineage undifferentiated stem/progenitor cells from normal human thyroid tissues. This seems to be achieved by direct reprogramming of thyroid follicular cells. The objective of the study was to reveal gene expression profile of the obtained cells compared to primary thyrocytes. After enzymatic digestion, primary thyrocytes, expressing thyroglobulin and cytokeratin-18, were cultured in a serum-free medium called SAGM containing insulin and EGF. Although the vast majority of cells died, a small proportion (~0.5%) survived and proliferated. During initial cell expansion, thyroglobulin/cytokeratin-18 expression was gradually declined, suggesting that those cells are derived from thyroid follicular cells or at least thyroid-committed cells. The SAGM-grown cells did not express any thyroid-specific genes. However, after four-week incubation with FBS and TSH, cytokeratin-18, thyroglobulin, TSH receptor, PAX8 and TTF1 expressions re-emerged. Moreover, surprisingly, the cells were capable of differentiating into neuronal or adipogenic lineage depending on differentiating conditions.
Dedifferentiation of human primary thyrocytes into multilineage progenitor cells without gene introduction.
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 SamplesEpigenetic regulation serves as the basis for stem cell differentiation into distinct cell types, but it is unclear how global epigenetic changes are regulated during this process. Here, we tested the hypothesis that global chromatin organization affects the lineage potential of stem cells and that manipulation of chromatin dynamics influences stem cell function. Using nuclease sensitivity assays, we found a progressive decrease in chromatin digestion between pluripotent embryonic stem cells (ESCs), multipotent hematopoietic stem and progenitor cells (HSPCs), and mature hematopoietic cells. Quantification of chromatin composition by high-resolution microscopy revealed that ESCs contain significantly more euchromatin than HSPCs, with a further reduction in euchromatin as HSPCs transition into mature cells. Increased cellular maturation also led to heterochromatin localization to the nuclear periphery. Functionally, prevention of heterochromatin formation by inhibition of the histone methyltransferase G9a resulted in delayed hematopoietic stem cell (HSC) differentiation. Our results demonstrate significant global rearrangements of chromatin structure during embryonic and adult stem cell differentiation, and that heterochromatin formation by H3K9 methylation is an important regulator of HSC differentiation. Overall design: Examination of gene expression profile of in vitro cultured mouse HSC with the G9a inhibitor UNC0638
Progressive Chromatin Condensation and H3K9 Methylation Regulate the Differentiation of Embryonic and Hematopoietic Stem Cells.
Specimen part, Cell line, Treatment, Subject
View SamplesAtrial fibrillation (AF) is a major risk factor for cardioembolic stroke. Anticoagulant drugs are effective in preventing AF-related stroke. However, the high frequency of anticoagulant-associated major bleeding is a major concern particularly when antiplatelet treatment is simultaneously administered. Here, microarray analysis in peripheral blood cells in eight patients with AF and stroke and eight AF subjects without stroke identified a stroke related gene expression pattern. HSPA1B, which encodes for heat-shock protein 70 kDa (Hsp70), was the most differentially expressed gene. This gene was downregulated in stroke subjects, a finding confirmed further in an independent AF cohort of 200 individuals. Hsp70 knock-out (KO) mice subjected to different thrombotic challenges developed thrombosis significantly earlier than their wild-type (WT) counterparts.
Hsp70 protects from stroke in atrial fibrillation patients by preventing thrombosis without increased bleeding risk.
Specimen part
View SamplesDefining the aging-cancer relationship is a challenging task. Mice deficient in Zmpste24, a metalloproteinase mutated in human progeria and involved in nuclear prelamin A maturation, recapitulate many features of aging. However, their short lifespan and cell-intrinsic and -extrinsic alterations restrict the application and interpretation of carcinogenesis protocols. To circumvent these limitations we have generated Zmpste24 mosaic mice. Interestingly, these mice develop normally - revealing cell-extrinsic mechanisms are preeminent in progeria- and display decreased incidence of infiltrating oral carcinomas. Moreover, ZMPSTE24 knock-down reduces human cancer cell invasiveness. Our results disclose the ZMPSTE24-prelamin A system as an example of antagonistic pleiotropy on cancer and aging, support the potential of cell-based and systemic therapies for progeria, and highlight ZMPSTE24 as a new anticancer target.
Prelamin A causes progeria through cell-extrinsic mechanisms and prevents cancer invasion.
Cell line
View SamplesTo understand at the molecular level the differences between old HSCs and young HSCs we have performed genome-wide analyses using Affymetrix Gene ST 1.0 microarrays with FACS purified cell populations. In contrast to other datasets comparing young and old HSCs, we compared both young and old HSCs and GMPs, and subtracted for genes that were also differentially expressed between young and old GMPs using a zero-intercept linear model. This allowed us to identify 913 significantly differentially expressed genes that were specific to old HSCs and segregated into different clusters.
Replication stress is a potent driver of functional decline in ageing haematopoietic stem cells.
Sex
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