Project description:Adult renal stem/progenitor cells (ARPCs), first identified in the BowmanM-bM-^@M-^Ys capsule, were recently identified also in the tubular compartment and it was demonstrated that renal progenitors from both locations were positive for PAX-2, CD133 and CD24 and exhibited multipotent differentiation ability. Recent studies indicated that microRNAs (miRNAs), a class of noncoding small RNAs that participate in the regulation of gene expression, may play a key role in stem cell self-renewal and differentiation. Distinct sets of miRNAs are specifically expressed in pluripotent stem cells but not in adult tissues, suggesting a role for miRNAs in stem cell self-renewal. We compared miRNA expression profiles of renal progenitors with that of renal proximal tubular cells (RPTECs) and of mesenchymal stem cells (MSC) and found distinct sets of miRNAs that were specifically expressed both in tubular and glomerular ARPCs. In particular, the miR-1915 and miR-1225-5p regulated the expression of important markers of renal progenitors, such as CD133 and PAX-2, and important genes involved in the repair mechanisms of ARPCs, such as TLR2. We demonstrated that the expression of both the renal stem cell markers CD133 and PAX-2 depends, at least in part, on lower miR-1915 levels and showed that the increase of miR-1915 levels improved capacity of ARPCs to differentiate into adipocyte-like and epithelial-like cells. Finally, we found that the low levels of miR-1225-5p were responsible for high TLR2 expression in ARPCs. Therefore, together, the miR-1915 and the miR-1225-5p seems to regulate important trait of ARPCs: the stemness and the repair capacity. Sixteen samples consisting of 5 glomerular and tubular ARPCs each, 3 MSCs, and 3 RPTECS.
Project description:Adult renal stem/progenitor cells (ARPCs), first identified in the Bowman’s capsule, were recently identified also in the tubular compartment and it was demonstrated that renal progenitors from both locations were positive for PAX-2, CD133 and CD24 and exhibited multipotent differentiation ability. Recent studies indicated that microRNAs (miRNAs), a class of noncoding small RNAs that participate in the regulation of gene expression, may play a key role in stem cell self-renewal and differentiation. Distinct sets of miRNAs are specifically expressed in pluripotent stem cells but not in adult tissues, suggesting a role for miRNAs in stem cell self-renewal. We compared miRNA expression profiles of renal progenitors with that of renal proximal tubular cells (RPTECs) and of mesenchymal stem cells (MSC) and found distinct sets of miRNAs that were specifically expressed both in tubular and glomerular ARPCs. In particular, the miR-1915 and miR-1225-5p regulated the expression of important markers of renal progenitors, such as CD133 and PAX-2, and important genes involved in the repair mechanisms of ARPCs, such as TLR2. We demonstrated that the expression of both the renal stem cell markers CD133 and PAX-2 depends, at least in part, on lower miR-1915 levels and showed that the increase of miR-1915 levels improved capacity of ARPCs to differentiate into adipocyte-like and epithelial-like cells. Finally, we found that the low levels of miR-1225-5p were responsible for high TLR2 expression in ARPCs. Therefore, together, the miR-1915 and the miR-1225-5p seems to regulate important trait of ARPCs: the stemness and the repair capacity.
Project description:Small hepatocyte-like progenitor cells (SHPCs) are hepatocytic progenitor cells that transiently form clusters in rat livers treated with retrorsine and with 70% partial hepatectomy (PH). We previously reported that transplantation of Thy1+ cells derived from D-galactosamine-treated livers promotes SHPC expansion, resulting in the acceleration of liver regeneration. Extracellular vesicles (EVs) produced by Thy1+ cells act on sinusoidal endothelial cells (SECs) and Kupffer cells to secrete IL17B and IL25, respectively, resulting in SHPC activation through IL17 receptor B (RB) signaling. Our aim is to identify factors in Thy1-EVs that activate IL17RB signaling. Thy1+ cells isolated from rats with D-galactosamine-induced liver injury were cultured for one week. Although some liver stem/progenitor cells proliferated into colonies, others maintained as mesenchymal cells (MCs). Thy1-MCs or Thy1-liver stem/progenitor cells were transplanted into retrorsine/PHtreated livers to examine their effects on SHPCs. SHs isolated from adult rat livers were used to validate factors regulating growth induction. The number and size of SHPCs remarkably increased in livers transplanted with Thy1-MCs. Comprehensive analysis of Thy1-MC-EVs revealed that miR-199a-5p, CINC-2, and MCP-1 are candidates for stimulating SHPC growth. Administration of the miR-199a-5p mimic, and not CINC-2, promoted SH growth. SECs treated with CINC-2 induced IL17b expression and their conditioned medium promoted SH growth. Thy1-MC transplantation may accelerate liver regeneration due to SHPCs expansion, which is stimulated by CINC-2/IL17RB signaling and miR-199a-5p.
Project description:Purpose: The aim of the present study was to identify and characterize in tissue samples of clear cell-renal cell carcinoma (ccRCC) a population of CD133+/CD24+ cancer cells (RCC-derived cells-RDCs) and to study the differences with their nonneoplastic counterpart, tubular Adult Renal Progenitor Cells (ARPCs). Materials and methods: CD133+/CD24+ RDCs were isolated from 40 patients. The mesenchymal phenotype and stemness proteomic profile of these RDCs were characterized. The colony-forming efficiency and self-renewal ability were tested with limiting dilution. The tumorigenic properties were evaluated in vitro with Soft Agar Assay. The angiogenic response was evaluated in vivo with the chorioallantoic membrane angiogenic assay. Microarray analysis was performed on 6 tARPCs and 6 RDCs clones. Expression of membrane proteins was evaluated with flowcytometry and immunofluorescence staining. Results: CD133+/CD24+ cells were isolated from normal and tumoral kidney tissue. FACS analysis showed that RDCs did not express the mesenchymal stem cell markers. We showed that CD133+/CD24+ tumor cells were more undifferentiated than tARPCs. RDCs were clonigenic and able to differentiate into adipocytes, epithelial and osteogenic cells. RDCs were able to regenerate tumor cells in vitro and to induce angiogenesis in vivo. The gene expression profile identified CTR2 as a membrane marker for this neoplastic population. Conclusions: Our results indicate the presence, in ccRCC, of a CD133+/CD24+/CTR2+ cancer cells population. These cells possess some stem cell-like features, including in vitro self-maintenance and differentiating capabilities, and are able to induce an angiogenic response in vivo. Study of gene expression profiling of Renal Cancer Cells (RCSCs), tubular Adult Renal Progenitor Cells (tARPCs), Renal Proximal Tubular Cells (RPTEC) and Mesenchymal Stem Cells (MSC). To highlight the similarities and the differences with known renal stem populations and with terminally differentiated renal cells, for each patient, 6 subcultures of tubular ARPCs (tARPCs), 3 subcultures of the MSC and 3 subcultures of the RPTEC were included in the analysis.
Project description:Physical exercise stimulates adult hippocampal neurogenesis in mammals, and is considered a relevant strategy for preventing age-related cognitive decline in aging humans. However, its mechanism is controversial. Here, by investigating microRNAs (miRNAs) and their downstream pathways, we uncover that downregulation of miR-135a-5p mediates exercise-induced proliferation of adult NPCs in adult neurogenesis in the mouse hippocampus, likely by activation of phosphatidylinositol (IP3) signaling. Specifically, while overexpression of miR-135 prevents exercise-induced proliferation in the adult mouse hippocampus in vivo and in NPCs in vitro, its inhibition activates NPCs proliferation in resting and aged mice. Label free proteomics and bioinformatics analysis identifies 11 potential targets of miR-135 in NPCs, several of them involved in phosphatidylinositol signaling. Thus, miR-135a is key in mediating exercise-induced adult neurogenesis and opens intriguing perspectives toward the therapeutic exploitation of miR-135 to delay or prevent pathological brain ageing.Physical exercise stimulates adult hippocampal neurogenesis in mammals, and is considered a relevant strategy for preventing age-related cognitive decline in aging humans. However, its mechanism is controversial. Here, by investigating microRNAs (miRNAs) and their downstream pathways, we uncover that downregulation of miR-135a-5p mediates exercise-induced proliferation of adult NPCs in adult neurogenesis in the mouse hippocampus, likely by activation of phosphatidylinositol (IP3) signaling. Specifically, while overexpression of miR-135 prevents exercise-induced proliferation in the adult mouse hippocampus in vivo and in NPCs in vitro, its inhibition activates NPCs proliferation in resting and aged mice. Label free proteomics and bioinformatics analysis identifies 11 potential targets of miR-135 in NPCs, several of them involved in phosphatidylinositol signaling. Thus, miR-135a is key in mediating exercise-induced adult neurogenesis and opens intriguing perspectives toward the therapeutic exploitation of miR-135 to delay or prevent pathological brain ageing.
Project description:Epigenetic regulations, such as DNA methylation and microRNAs, play an important role in renal fibrosis. Here, we report the regulation of microRNA-219a-2 (mir-219a-2) by DNA methylation in fibrotic kidneys, unveiling the crosstalk between these epigenetic mechanisms. Through genome-wide DNA methylation analysis and pyro-sequencing, we detected the hypermethylation of mir-219a-2 in renal fibrosis induced by unilateral ureter obstruction (UUO) or renal ischemia/reperfusion, which was accompanied by a significant decrease in mir-219a-5p expression. Functionally, overexpression of mir-219a-2 enhanced fibronectin induction during hypoxia or TGF-b1 treatment of cultured renal cells. In mice, inhibition of mir-219a-5p suppressed fibronectin accumulation in UUO kidneys. ALDH1L2 was identified to be the direct target gene of mir-219a-5p in renal fibrosis. Mir-219a-5p suppressed ALDH1L2 expression in cultured renal cells, while inhibition of mir-219a-5p prevented the decrease of ALDH1L2 in UUO kidneys. Knockdown of ALDH1L2 enhanced PAI-1 induction during TGF-b1 treatment of renal cells, which was associated with fibronectin expression. In conclusion, the hypermethylation of mir-219a-2 in response to fibrotic stress attenuates mir-219a-5p expression and induces the up-regulation of its target gene ALDH1L2, which may reduce fibronectin deposition by suppressing PAI-1.
Project description:Epigenetic regulations, such as DNA methylation and microRNAs, play an important role in renal fibrosis. Here, we report the regulation of microRNA-219a-2 (mir-219a-2) by DNA methylation in fibrotic kidneys, unveiling the crosstalk between these epigenetic mechanisms. Through genome-wide DNA methylation analysis and pyro-sequencing, we detected the hypermethylation of mir-219a-2 in renal fibrosis induced by unilateral ureter obstruction (UUO) or renal ischemia/reperfusion, which was accompanied by a significant decrease in mir-219a-5p expression. Functionally, overexpression of mir-219a-2 enhanced fibronectin induction during hypoxia or TGF-b1 treatment of cultured renal cells. In mice, inhibition of mir-219a-5p suppressed fibronectin accumulation in UUO kidneys. ALDH1L2 was identified to be the direct target gene of mir-219a-5p in renal fibrosis. Mir-219a-5p suppressed ALDH1L2 expression in cultured renal cells, while inhibition of mir-219a-5p prevented the decrease of ALDH1L2 in UUO kidneys. Knockdown of ALDH1L2 enhanced PAI-1 induction during TGF-b1 treatment of renal cells, which was associated with fibronectin expression. In conclusion, the hypermethylation of mir-219a-2 in response to fibrotic stress attenuates mir-219a-5p expression and induces the up-regulation of its target gene ALDH1L2, which may reduce fibronectin deposition by suppressing PAI-1.
Project description:From a previous microarray study we developed a small chondrogenesis model. We performed qPCR and measured how knockdown of miR-199a-5p or miR-199b-5p could modulate chondrogenesis. Several experiments were used to determine the parameters of this model. We utilised parameter scan and manual sliding to refine the model. Within are two models - an initial model which only comprises of genes which we have data for, and an enhanced model which expands of the initial model to make more predictions - e.g. how miR-140-5p is indirectly regulated by miR-199a-5p and miR-199b-5p.
Project description:In order to identify the targets of miR-193a-5p in osteosarcoma U2OS cell line, we used a lentivirus-mediated expression system to overexpressing miR-193a precusor, miR-193a-5p target sequence and non-target sequence, respectively, in osteosarcoma cell line U2OS. A tandem mass tag (TMT)-based quantitative proteomic strategy was employed to identify the global profile of miR-193a-5p-regulated proteins. order to identify the targets of miR-193a-5p, we used a lentivirus-mediated expression system to overexpressing miR-193a precusor, miR-193a-5p target sequence and non-target sequence, respectively, in osteosarcoma cell line U2OS. A tandem mass tag (TMT)-based quantitative proteomic strategy was employed to identify the global profile of miR-193a-5p-regulated proteins.
Project description:MiRNAs regulate posttranscriptional gene expression and are widely implicated in the pathogenesis of complex diseases. We aim to elucidate miRNA regulation of the atrial mRNA signatures that associate with AF. This may provide novel mechanistical insights and candidate targets for therapies using miRNA mimics or antimiRs.
We present combined miRNAs-mRNAs sequencing in atrial tissues of patient without AF (n=22), with paroxysmal AF (n=22) and with persistent AF (n=20). MiRNA and mRNA signatures followed an ordinal scale from nonAF to paroxysmal to persistent AF patients. The previously reported mRNA sequencing identified 5228 differentially expressed genes involved in epithelial to mesenchymal transition, endothelial cell proliferation and extracellular matrix remodelling involving collagens, glycoproteins and proteoglycans. We discovered 103 differentially expressed miRNAs. Key downregulated miRNAs included miR-135b-5p, miR-138-5p, miR-200a-3p, miR-200b-3p and miR-31-5p and key upregulated miRNAs were miR-144-3p, miR-15b-3p, miR-182-5p miR-18b-5p, miR-4306 and miR-206. The expression levels of differentially expressed miRNAs were negatively correlated with the expression levels of their predicted target mRNAs. The downregulated miRNAs demonstrated a more profound transcriptome effect than the upregulated miRNAs. Upregulated biological processes enriched in miRNAs targets related to epithelial and endothelial cell migration and glycosaminoglycan biosynthesis, in line with the processes discovered by the mRNA sequencing analysis.
Combined analysis of miRNA and mRNA sequencing uncovered miRNAs with a broad transcriptional effect in human AF. Epithelial to mesenchymal transition and endothelial cell proliferation were processes controlled by downregulated miR-135b-5p, miR-138-5p, miR-200a-3p, miR-200b-3p and miR-31-5p, which in turn may contribute to (myo)fibroblast activation and structural remodeling.\