Extracellular purines promote the differentiation capacity of human bone marrow-derived mesenchymal stem cells
ABSTRACT: Extracellular nucleotides are potent signaling molecules mediating cell-specific biological functions. We previously demonstrated that adenosine 5'-triphosphate (ATP) inhibits the proliferation while stimulating the migration, in vitro and in vivo, of human bone marrow-derived mesenchymal stem cells (BM-hMSC). Here, we investigated the effects of ATP on BM-hMSC differentiation capacity. Molecular analysis showed that ATP treatment modulated the expression of several genes (e.g. wnt-pathway-related genes) governing osteoblastic and adipogenic differentiation of MSCs. Functional studies demonstrated that ATP, under specific culture conditions, stimulated adipogenic and osteogenic differentiation by significantly increasing the lipid accumulation and the expression levels of the adipogenic master gene PPARγ (peroxisome proliferator activated receptor-gamma) and by promoting the mineralization and the expression of the osteoblast-related gene RUNX2 (Runt-related transcription factor 2), respectively. BM-hMSCs cells were transiently exposed to ATP 1mM for 24 hours (ATP pre-treatment) before starting differentiation induction. Then, BM-hMSCs were cultured under adipogenic/osteogenic conditions. Gene Expression Profile was performed on differentiate cells after 3 weeks of induction culture.
Project description:We report ChIP-seq for C/EBPb and ATF4 in human mesenchymal stem cells and in a cell-free system using naked genomic DNA. ChIP-Seq for GR, RNA Polymerase II, and H3K27 acetylation in hMSCs cultured under different adipogenic conditions are also presented. hMSCs cultured at high or low cell seeding densities in the presence or absence of adipogenic induction cocktail
Project description:Nucleotides triphosphates are extracellular messengers binding to specific plasma membrane receptors (P2Rs) that modulate responses as different as proliferation, differentiation, migration or cell death on several cell types including hematopoietic stem cells. Little and controversial information is available on the role of extracellular nucleotides in human mesenchimal stem cells (hMSCs). In this study, we assessed whether P2Rs are expressed and functional in bone marrow-derived hMSCs. Our results demonstrated, at the mRNA and protein level, the expression of all P2X and P2Y receptor subtypes identified so far. P2R activation by their natural ligands adenosine triphosphate (ATP) and uridine triphosphate (UTP) induced in hMSCs, intracellular Ca2+ concentration changes, plasma membrane depolarization and permeabilization. hMSCs were resistant to the cytotoxic effects of high dose ATP despite the expression of permeabilizing P2Rs as demonstrated by the lack of morphological changes, significant release of intracellular markers of cell death or modification of the mitochondrial network. Gene expression profiling revealed the down-regulation of cell proliferation genes whereas genes involved in cell migration and cytokine production were strongly up-regulated by ATP. Functional studies confirmed the inhibitory activity of ATP on proliferation of hMSCs and clonogenic progenitors. Moreover, ATP exerted a chemotactic effect on hMSCs and increased their migration in response to the chemokine CXCL12. Finally, whereas ATP did not affect T-cell inhibitory activity of hMSCs, the nucleotide increased the production of pro-inflammatory cytokines by hMSCs. Thus, our data show that purinergic signaling modulates hMSC functions and point to a role for extracellular nucleotides on hMSCs biology. hMSCs from 6 healthy donors were seeded at a density of 2.5 x 103 cells/cm2 for 24 hours with or without 1mM ATP. We then assessed the transcriptome profile of ATP–treated and untreated cells using Affymetrix HG-U133 Plus 2 GeneChip array.
Project description:We have previously reported that the deficiency of p53 alone or in combination with Rb (Rb-/- p53-/-) in adipose-derived MSCs (ASCs) promotes leiomyosarcoma-like tumors in vivo. Here, we hypothesized that the source of MSCs and/or the cell differentiation stage could determine the phenotype of sarcoma development. To investigate whether there is a link between the source of MSCs and sarcoma phenotype, we generated p53-/- and Rb-/-p53-/- MSCs from bone marrow (BM-MSCs). Both genotypes of BM-MSCs initiated leiomyosarcoma formation similar to p53-/- and Rb-/-p53-/- ASCs. In addition, gene expression profiling revealed a link between p53- or Rb-p53-deficient BM-MSCs and ASCs and muscle-associated sarcomagenesis. These data suggest that the tissue source of MSC does not seem a crucial factor in the development of a particular sarcoma phenotype. To analyze whether the differentiation stage defines the sarcoma phenotype, BM-MSCs and ASCs were induced to differentiate towards the osteogenic lineage, and both p53 and Rb were excised using Cre-expressing adenovectors at different stages along osteogenic differentiation. Regardless of the level of osteogenic commitment, the inactivation of Rb and p53 in BM-MSC-derived, but not in ASC-derived, osteogenic progenitors gave rise to osteosarcoma-like tumors which could be serially transplanted. This indicates that the osteogenic differentiation stage of BM-MSCs imposes the phenotype of in vivo sarcoma development, and that BM-MSC-derived osteogenic progenitors rather than undifferentiated BM-MSCs, undifferentiated ASCs or ASC-derived osteogenic progenitors, represent the cell of origin for osteosarcoma development. To analyse whether the BM-MSC and Fat-MSC (ASC) differentiation stage may define the sarcoma phenotype, RbloxP/loxPp53loxP/loxP BM-MSCs and ASCs were induced to differentiate towards the osteogenic lineage and both Rb and p53 were excised with adenoviral vectors expressing the Cre-recombinase gene (Ad-CMV-Cre) at different stages (day 0 and 10) along osteogenic differentiation. NSG mice were inoculated subcutaneously with 5×10^6 mutant cells. Animals were killed when tumors reached 1 cm3 or 150 days after infusion. Some of the obtained tumors were mechanically disaggregated to establish ex vivo MSC-transformed cell lines. Gene expression analysis was performed using: WT BM-MSCs and ASCs, Rb-/-p53-/- BM-MSCs and ASCs previously differentiated to the osteogenic lineage for 10 days and a tumor cell line derived from p53-/-Rb-/- BM-MSC differentiated to the osteogenic lineage for 10 days.
Project description:Extracellular nucleotides are potent signaling molecules mediating cell-specific biological functions. We previously demonstrated that adenosine 5'-triphosphate (ATP) inhibits the proliferation while stimulating the migration, in vitro and in vivo, of human bone marrow-derived mesenchymal stem cells (BM-hMSC). Here, we investigated the effects of ATP on BM-hMSC differentiation capacity. Molecular analysis showed that ATP treatment modulated the expression of several genes (e.g. wnt-pathway-related genes) governing osteoblastic and adipogenic differentiation of MSCs. Functional studies demonstrated that ATP, under specific culture conditions, stimulated adipogenic and osteogenic differentiation by significantly increasing the lipid accumulation and the expression levels of the adipogenic master gene PPARγ (peroxisome proliferator activated receptor-gamma) and by promoting the mineralization and the expression of the osteoblast-related gene RUNX2 (Runt-related transcription factor 2), respectively. Overall design: BM-hMSCs cells were transiently exposed to ATP 1mM for 24 hours (ATP pre-treatment) before starting differentiation induction. Then, BM-hMSCs were cultured under adipogenic/osteogenic conditions. Gene Expression Profile was performed on differentiate cells after 3 weeks of induction culture.
Project description:The response of osteoprogenitors to calcium (Ca2+) is of primary interest for both normal bone homeostasis and the clinical field of bone regeneration. The latter makes use of calcium phosphate-based bone void fillers to heal bone defects, but it is currently not known how Ca2+ released from these ceramic materials influences cells in situ. Here, we have created an in vitro environment with high extracellular Ca2+ concentration and investigated the response of human bone marrow-derived mesenchymal stromal cells (hMSCs) to it. Ca2+ enhanced proliferation and morphological changes in hMSCs. Moreover, the expression of osteogenic genes is highly increased. A 3-fold up-regulation of BMP-2 is observed after only 6 h and pharmaceutical interference with a number of proteins involved in Ca2+ sensing showed that not the calcium sensing receptor, but rather type L voltage-gated calcium channels are involved in mediating the signaling pathway between extracellular Ca2+ and BMP-2 expression. MEK1/2 activity is essential for the effect of Ca2+ and using microarray analysis, we have identified c-Fos as an early Ca2+ response gene. We have demonstrated that hMSC osteogenesis can be induced via extracellular Ca2+, a simple and economic way of priming hMSCs for bone tissue engineering applications. For more information check: https://cbit.maastrichtuniversity.nl/
Project description:Total small RNA was isolated from BM-MSCs obtained from OA diagnosed patients (n=10) and non-OA (n=10 after osteogenic induction for 1, 10 and 21 days. miRNAs, were initially screened and those with consistent differential expression were selected for further validation by qRT-PCR analysis. From an initial screening of 246 differentially expressed miRNAs (fold change ≥± 2, P ≤0.05) between OA and non-OA BM-MSC samples 21 were selected and validated by qRT-PCR
Project description:Adipose-derived and bone-marrow-derived mesenchymal stem cells were collected from 3 pigs and cultivated in vitro up to 3 passages. At passage 3 cells were cultured to 80% confluence and induced to differentiate in adipose and bone. Cell were harvested at 0 day of differentiation (dd) or pre-differentiation, at 2, 7, and 21dd for RNA extraction. The RNA was used for a large microarray analysis using a specific pig oligo-array with >10,000 annotated genes. The main aim of the microarray analysis was to directly compare the two transcriptomics adaptation of the two mesenchymal stem cells during osteogenic and adipogenic differentiation The mesenchymal stem cells were harvested at 0, 2, 7, and 21 day of differentiation (dd). A dye-swap reference design (reference = mixture of RNA from several porcine tissues) was used.
Project description:Osteogenic differentiation of human mesenchymal stromal cells (hMSCs) may potentially be used in cell-based bone tissue-engineering applications to enhance the bone-forming potential of these cells. Osteogenic differentiation and adipogenic differentiation are thought to be mutually exclusive, and although several signaling pathways and cues that induce osteogenic or adipogenic differentiation, respectively, have been identified, there is no general consensus on how to optimally differentiate hMSCs into the osteogenic lineage. Some pathways have also been reported to be involved in both adipogenic and osteogenic differentiation, as for example, the protein kinase A (PKA) pathway, and the aim of this study was to investigate the role of cAMP/PKA signaling in differentiation of hMSCs in more detail. We show that activation of this pathway with dibutyryl-cAMP results in enhanced alkaline phosphatase expression, whereas another cAMP analog induces adipogenesis in long-term mineralization cultures. Adipogenic differentiation, induced by 8-bromo-cAMP, was accompanied by stronger PKA activity and higher expression of cAMP-responsive genes, suggesting that stronger activation correlates with adipogenic differentiation. In addition, a whole-genome expression analysis showed an increase in expression of adipogenic genes in 8-br-cAMP-treated cells. Furthermore, by means of quantitative polymerase chain reaction, we show differences in peroxisome proliferator-activated receptor-gamma activation, either alone or in combination with dexamethasone, thus demonstrating differential effects of the PKA pathway, most likely depending on its mode of activation.
Project description:LncRNA transcriptional profiling of human mesenchymal stem cells comparing control undifferentiated HMSC with Day3 and Day6 adipogenic differentiation stages Three-condition experiment, Day0 vs. Day3 vs Day6 cells. Day0: 4 replicates, Day3: 3 replicates and Day6: 3 replicates.
Project description:In animal models and human trials, intramyocardial injection of adult bone-marrow derived mesenchymal stem cells (BM-MSC) provides beneficial effects in failing hearts. These effects are mainly mediated through paracrine mechanisms. Mesenchymal stem cells of fetal origin (hAMC) can be isolated from the amniotic membrane of human placenta. Our results provide evidence that hAMC exert remarkable cardioprotective effects through paracrine mechanisms. However, the complete nature and scope of the paracrine mediators of cardioprotection have not been investigated yet. We compared the gene expression profiling of hAMC (n=8), BM-MSC (n=10) and dermal fibroblasts (n=6) to shed light onto the identity of putative cardioprotective factors secreted by fetal MSC. Total RNA was extracted from cultured hAMC (n=8), BM-MSC (n=10) and dermal fibroblasts (n=6) and analyzed with HumanHT-12 v3 Expression BeadChips