Similar Datasets
Project description:Regenerative capabilities of the endothelium rely on vessel-resident progenitors termed endothelial colony forming cells (ECFCs). This study aimed to investigate if these progenitors are impacted by conditions (i.e., obesity or atherosclerosis) characterized by increased serum levels of oxidized low-density lipoprotein (oxLDL), a known inducer of Endothelial-to-Mesenchymal Transition (EndMT). Our investigation focused on understanding the effects of EndMT on the self-renewal capabilities of progenitors and the associated molecular alterations. In the presence of oxLDL, ECFCs displayed classical features of EndMT, through reduced endothelial gene and protein expression, function as well as increased mesenchymal genes, contractility, and motility. Additionally, ECFCs displayed a dramatic loss in self-renewal capacity in the presence of oxLDL. RNA-sequencing analysis of ECFCs exposed to oxLDL validated gene expression changes suggesting EndMT and identified SOX9 as one of the highly differentially expressed genes. ATAC sequencing analysis identified SOX9 binding sites associated with regions of dynamic chromosome accessibility resulting from oxLDL exposure, further pointing to its importance. EndMT phenotype and gene expression changes induced by oxLDL in vitro or high fat diet (HFD) in vivo were reversed by the silencing of SOX9 in ECFCs or the endothelial-specific conditional knockout of Sox9 in murine models. Overall, our findings support that EndMT affects vessel-resident endothelial progenitor's self-renewal. SOX9 activation is an early transcriptional event that drives the mesenchymal transition of endothelial progenitor cells. The identification of the molecular network driving EndMT in vessel-resident endothelial progenitors presents a new avenue in understanding and preventing a range of condition where this process is involved.
| S-EPMC11303482 | biostudies-literature
Project description:Regenerative capabilities of the human endothelium are governed by vessel-resident progenitors termed endothelial colony forming cells (ECFCs). Endothelial cells acquire mesenchymal phenotypes during atherogenesis, via a process termed endothelial-to-mesenchymal transition (EndMT). This study aimed to investigate the molecular drivers of EndMT in the progenitor population under an atherogenic model. In the presence of oxidised low-density lipoprotein (oxLDL), cultured human ECFCs displayed classical features of EndMT, through reduced endothelial gene and protein expression, function as well as increased mesenchymal genes, contractility, and motility. Importantly, in vitro oxLDL resulted in a dramatic loss in progenitor self-renewal through single-cell colony formation assay and numbers. RNA sequencing of ECFCs exposed or not to oxLDL validated gene expression changes suggesting EndMT but identified SOX9 as one of the highly differentially expressed genes. ATACseq revealed SOX9 binding sites were associated with regions of dynamic chromosome accessibility resulting from exposure to oxLDL. EndMT phenotype and gene expression changes induced by oxLDL in vitro or high fat diet (HFD) in vivo was reversed by an shRNA knockdown of SOX9 or endothelial specific conditional knockout of Sox9 in murine models respectively. Finally, analysis of single cell RNA sequencing of human atherosclerotic aorta identified endothelial populations with mesenchymal characteristics overexpressing SOX9 when compared to controls. Overall, our findings support that in the atherogenic process, EndMT induced by oxLDL or HFD is driven by SOX9 and strongly affects progenitor function opening new avenues for targeting this process.
2024-08-30 | GSE247711 | GEO
Project description:Regenerative capabilities of the human endothelium are governed by vessel-resident progenitors termed endothelial colony forming cells (ECFCs). Endothelial cells acquire mesenchymal phenotypes during atherogenesis, via a process termed endothelial-to-mesenchymal transition (EndMT). This study aimed to investigate the molecular drivers of EndMT in the progenitor population under an atherogenic model. In the presence of oxidised low-density lipoprotein (oxLDL), cultured human ECFCs displayed classical features of EndMT, through reduced endothelial gene and protein expression, function as well as increased mesenchymal genes, contractility, and motility. Importantly, in vitro oxLDL resulted in a dramatic loss in progenitor self-renewal through single-cell colony formation assay and numbers. RNA sequencing of ECFCs exposed or not to oxLDL validated gene expression changes suggesting EndMT but identified SOX9 as one of the highly differentially expressed genes. ATACseq revealed SOX9 binding sites were associated with regions of dynamic chromosome accessibility resulting from exposure to oxLDL. EndMT phenotype and gene expression changes induced by oxLDL in vitro or high fat diet (HFD) in vivo was reversed by an shRNA knockdown of SOX9 or endothelial specific conditional knockout of Sox9 in murine models respectively. Finally, analysis of single cell RNA sequencing of human atherosclerotic aorta identified endothelial populations with mesenchymal characteristics overexpressing SOX9 when compared to controls. Overall, our findings support that in the atherogenic process, EndMT induced by oxLDL or HFD is driven by SOX9 and strongly affects progenitor function opening new avenues for targeting this process.
2024-08-30 | GSE247709 | GEO
Project description:Distinct roles of SOX9 in self-renewal of progenitors and mesenchymal transition of the endothelium
| PRJNA1040198 | ENA
Project description:Distinct roles of SOX9 in self-renewal of progenitors and mesenchymal transition of the endothelium [ATAC-seq]
| PRJNA1040199 | ENA
Project description:Distinct roles of SOX9 in self-renewal of progenitors and mesenchymal transition of the endothelium [RNA-seq]
| PRJNA1040200 | ENA
Project description:Endothelial to mesenchymal transition (EndMT) is a leading cause of fibrosis and disease, however its mechanism has yet to be elucidated. The endothelium possesses a profound regenerative capacity to adapt and reorganize that is attributed to a population of vessel-resident endovascular progenitors (EVP) governing an endothelial hierarchy. Here, using fate analysis, we show that two transcription factors SOX9 and RBPJ specifically affect the murine EVP numbers and regulate lineage specification. Conditional knock-out of Sox9 from the vasculature (Sox9fl/fl/Cdh5-CreER RosaYFP) depletes EVP while enhancing Rbpj expression and canonical Notch signalling. Additionally, skin wound analysis from Sox9 conditional knock-out mice demonstrates a significant reduction in pathological EndMT resulting in reduced scar area. The converse is observed with Rbpj conditionally knocked-out from the murine vasculature (Rbpjfl/fl/Cdh5-CreER RosaYFP) or inhibition of Notch signaling in human endothelial colony forming cells, resulting in enhanced Sox9 and EndMT related gene (Snail, Slug, Twist1, Twist2, TGF-β) expression. Similarly, increased endothelial hedgehog signaling (Ptch1fl/fl/Cdh5-CreER RosaYFP), that upregulates the expression of Sox9 in cells undergoing pathological EndMT, also results in excess fibrosis. Endothelial cells transitioning to a mesenchymal fate express increased Sox9, reduced Rbpj and enhanced EndMT. Importantly, using topical administration of siRNA against Sox9 on skin wounds can substantially reduce scar area by blocking pathological EndMT. Overall, here we report distinct fates of EVPs according to the relative expression of Rbpj or Notch signalling and Sox9, highlighting their potential plasticity and opening exciting avenues for more effective therapies in fibrotic diseases.
| S-EPMC8105340 | biostudies-literature
Project description:In vertebrate retina, histogenesis occurs over an extended period. To sustain the temporal generation of diverse cell types, retinal progenitor cells (RPCs) must self-renew. However, self-renewal and regulation of RPCs remain poorly understood. Here, we demonstrate that cell-extrinsic factors coordinate with the epigenetic regulator high-mobility group AT-hook 2 (Hmga2) to regulate self-renewal of late retinal progenitor cells (RPCs). We observed that a small subset of RPCs was capable of clonal propagation and retained multipotentiality of parents in the presence of endothelial cells (ECs), known self-renewal regulators in various stem cell niches. The self-renewing effects, also observed in vivo, involve multiple intercellular signaling pathways, engaging Hmga2. As progenitors exhaust during retinal development, expression of Hmga2 progressively decreases. Analyses of Hmga2-expression perturbation, in vitro and in vivo, revealed that Hmga2 functionally helps to mediate cell-extrinsic influences on late-retinal progenitor self-renewal. Our results provide a framework for integrating the diverse intercellular influences elicited by epigenetic regulators for self-renewal in a dynamic stem cell niche: the developing vertebrate retina.
| S-EPMC4302892 | biostudies-literature
Project description:The damage of the skeletal muscle prompts a complex and coordinated response that involves the interactions of many different cell populations and promotes inflammation, vascular remodeling and finally muscle regeneration. Muscle disorders exist in which the irreversible loss of tissue integrity and function is linked to defective neo-angiogenesis with persistence of tissue necrosis and inflammation. Here we show that macrophages (MPs) are necessary for efficient vascular remodeling in the injured muscle. In particular, MPs sustain the differentiation of endothelial-derived progenitors to contribute to neo-capillary formation, by secreting pro-angiogenic growth factors. When phagocyte infiltration is compromised endothelial-derived progenitors undergo a significant endothelial to mesenchymal transition (EndoMT), possibly triggered by the activation of transforming growth factor-β/bone morphogenetic protein signaling, collagen accumulates and the muscle is replaced by fibrotic tissue. Our findings provide new insights in EndoMT in the adult skeletal muscle, and suggest that endothelial cells in the skeletal muscle may represent a new target for therapeutic intervention in fibrotic diseases.
| S-EPMC4040684 | biostudies-literature
Project description:Maintenance of the adipose tissue requires a proper balance between self-renewal and differentiation of adipose progenitors (AP). Any deregulation leads either to fat overexpansion and obesity or fat loss and consequent lipodystrophies. Depending on the fat pad location, APs and adipocytes are heterogeneous. However, information on the pharmacological sensitivity of distinct APs to drugs known to alter the function of adipose tissue, especially HIV protease inhibitors (PIs) is scant. Here we show that PIs decreased proliferation and clonal expansion of APs, modifying their self-renewal potential. Lopinavir was the most potent PI tested. Decrease in self-renewal was accompanied by a reduced expression of the immediate early response gene IER3, a gene associated with tissue expansion. It was more pronounced in chin-derived APs than in knee-derived APs. Furthermore, lopinavir lowered the activin A-induced ERK1/2 phosphorylation. Expressions of the transcription factor EGR1 and its targets, including INHBA were subsequently altered. Therefore, activin A secretion was reduced leading to a dramatic impairment of APs self-renewal sustained by the activin A autocrine loop. All together, these observations highlight the activin A autocrine loop as a crucial effector to maintain APs self-renewal. Targeting this pathway by HIV-PIs may participate in the induction of unwanted side effects.
| S-EPMC5462747 | biostudies-literature