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:We aimed at extending the repertoire of high-quality miRNA normalizers for reverse transcription-quantitative PCR (RT-qPCR) of human plasma with special emphasis on the extremely guanine-cytosine-rich portion of the miRNome. For high-throughput selection of stable candidates, microarray technology was preferred over small-RNA sequencing (sRNA-seq) since the latter underrepresented miRNAs with a guanine-cytosine (GC) content of at least 75% (p = 0.0002, n = 2). miRNA abundances measured on the microarray were ranked for consistency and uniformity using nine normalization approaches. The eleven most stable sequences included miRNAs of moderate, but also extreme GC content (45%–65%: miR-320d, miR-425-5p, miR-185-5p, miR-486-5p; 80%–95%: miR-1915-3p, miR-3656-5p, miR-3665-5p, miR-3960-5p, miR-4488-5p, miR-4497 and miR-4787-5p). In contrast, the seven extremely GC-rich miRNAs were not found in the two plasma miRNomes screened by sRNA-seq. Stem-loop RT-qPCR was employed for stability verification in 32 plasma samples of healthy male Caucasians (age range: 18–55 years). In general, inter-individual variance of miRNA abundance was low or very low as indicated by coefficient of variation (CV) values of 0.6%–8.2%. miR-3665 and miR-1915-3p outperformed in this analysis (CVs: 0.6 and 2.4%, respectively). The eight most stable sequences included four extremely GC-rich miRNAs (miR-1915-3p, miR-3665, miR-4787-5p and miR-4497). The best-performing duo normalization factor (NF) for the condition of human plasma, miR-320d and miR-4787-5p, also included a GC-extreme miRNA. In summary, the identification of extremely guanine-cytosine-rich plasma normalizers will help to increase accuracy of PCR-based miRNA quantification, thus raise the potential that miRNAs become markers for psychological stress reactions or early and precise diagnosis of clinical phenotypes. The novel miRNAs might also be useful for orthologous contexts considering their conservation in related animal genomes.
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:The corneal epithelium is maintained by limbal epithelial stem cells (LESCs) and is largely responsible for corneal optical transparency and protection by continuously renewing population of corneal epithelial cells. Diabetes mellitus (DM) affects all structures of the eye including the cornea, which can result in delayed wound healing and potential vision loss. MicroRNAs (miRNAs) are short non-coding oligonucleotides that regulate various cellular functions, including oxidative stress response, by repressing protein translation. MiR-10b-5p was previously identified to be upregulated in diabetic vs. non-diabetic limbal cells, and our purpose was to understand the role of miR-10b-5p in human limbal epithelial cells in healthy and diabetic conditions. Through integrated transcriptomic and proteomic analyses, we identified GCLM and LANCL1 as key miR-10b-5p targets, revealing its profound impact on glutathione metabolism, sulfur compound biosynthesis processes, and antioxidant defenses. Our findings suggest that overexpression of miR-10b disrupts redox balance, which potentially leads to heightened oxidative stress and increased cellular vulnerability in diabetic corneas. Understanding miR-10b function in corneal epithelial cells may pave the way for novel therapeutic strategies to mitigate oxidative stress and normalize corneal health in diabetic patients.
Project description:Cutaneous squamous cell carcinoma (cSCC) is the second most commonly diagnosed cancer in the United States each year. Despite a generally good prognosis, metastatic cSCC results in over 3500 deaths annually. There are no specifically targeted therapies or biomarkers for metastatic cSCC. To determine whether aberrant microRNA expression occurs in metastatic cSCC which could provide novel targets for therapy or biomarkers for earlier diagnosis or prognosis, microRNA expression profiling was performed in 48 samples including normal skin, primary tumors and metastases. Multiple microRNAs showed differential expression; miR-4286, miR-200a-3p and miR-148-3p showed increased expression and miR-1915-3p, miR-205-5p, miR-4516 and miR-150-5p showed reduced expression in metastatic samples. Several microRNAs previously showing aberrant expressionshown to be aberrantly expressed in primary cSCCs were also observed in this study including miR-100, miR-135b, miR-145, miR-21, and miR-214. In summary, several microRNAs show differential expression between primary and metastatic cSCCs; these may be useful as biomarkers for metastasis or as targets for therapytherapeutic targets. RNA extracted from primary human tissues
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: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: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.\