Project description:We have recently confirmed miR-27a-3p as a crucial regulator of human adipogenesis (Wu H, Pula T, Tews D, Amri E-Z, Debatin K-M, Wabitsch M, Fischer-Posovszky P, Roos J. microRNA-27a-3p but Not -5p Is a Crucial Mediator of Human Adipogenesis. Cells. 2021; 10(11):3205. https://doi.org/10.3390/cells10113205 ). MiR-27a-5p did not impair human adipogenesis. However, since several publications state that miR-27a ist also a crucial regulator of UCP1, we were interested if miR-27a-3p or miR-27a-5p regulatas UCP1 and other thermogenesis related genes. We found a strong regulation of UCP1 with functional relevance for the cellular metabolism by miR-27a-5p.To asesse the mRNA gene expression pattern, mRNA sequencing was performed.
Project description:Pancreatic β-cell dysfunction caused by obesity can be associated with alterations in the levels of microRNAs (miRNAs). However, the role of miRNAs in such processes remains elusive. Here, we show that pancreatic islet miR-27a-5p, which is markedly increased in obese mice and impairs insulin secretion, is mainly delivered by visceral adipocyte-derived extracellular vesicles (EVs). Depleting miR-27a-5p significantly improves insulin secretion and glucose intolerance in db/db mice. Supporting the function of EVs’ miR-27a-5p as a key pathogenic factor, intravenous injection of miR-27a-5p-containing EVs shows their distribution in mouse pancreatic islets. Tracing the injected AAV-miR-27a-5p (AAV-miR-27a) or AAV-FABP4-miR-27a-5p (AAV-FABP4-miR-27a) in visceral fat results in upregulating miR-27a-5p in EVs and serum, and elicits mouse pancreatic β-cell dysfunction. Mechanistically, miR-27a-5p directly targets L-type Ca2+ channel subtype CaV1.2 (Cacna1c) and reduces insulin secretion in β-cells. Overexpressing mouse CaV1.2 largely abolishes the insulin secretion injury induced by miR-27a-5p. These findings reveal a causative role of EVs’ miR-27a-5p in visceral adipocyte-mediated pancreatic β-cell dysfunction in obesity-associated type 2 diabetes mellitus.
Project description:BMSC-derived exosomes from ovariectomized rats (OVX-Exo) and sham-operated rats (Sham-Exo) were co-cultured with bone marrow-derived macrophages to study their effects on osteoclast differentiation. Next-generation sequencing was utilized to identify the differentially expressed miRNAs (DE-miRNAs) in OVX-Exo and Sham-Exo, while target genes were analyzed using bioinformatics. The regulatory effects of miR-27a-3p and miR-196b-5p on osteogenic differentiation of BMSCs and osteoclast differentiation were verified by gain-of-function and loss-of-function analyses.Osteoclast differentiation was significantly enhanced in the OVX-Exo treatment group compared to the Sham-Exo group. Twenty DE-miRNAs were identified in OVX-Exo and Sham-Exo, among which miR-27a-3p and miR-196b-5p promoted the expressions of osteogenic genes in BMSCs. In contrast, knockdown of miR-27a-3p and miR-196b-5p increased the expressions of osteoclastic genes in osteoclasts. These 20 DE-miRNAs were found to target 11435 mRNAs. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses revealed that these target genes were involved in several biological processes and osteoporosis-related signaling pathways.
Project description:The transition of the endothelium to a pro-inflammatory state is key to progression of chronic inflammatory diseases including rheumatoid arthritis, chronic bowel disease and atherosclerosis. In atherosclerosis it is hypothesized that low density lipoproteins (LDL) that become trapped in the intima of the blood vessels are oxidized to minimally modified LDL (mmLDL) and that these serve as an important contributing factors to endothelial dysfunction. Oxidized 1-palmitoyl-2-arachidonoyl-sn-glycero-3-phosphatidylcholine (OX-PAPC), a model of the active phospholipid components of mmLDL affects the expression of hundreds of genes involved in inflammatory and other biological processes in human aortic endothelial cells (HAECs). We hypothesized that microRNAs (miRNAs) partially regulate this response. Using next generation sequencing, we identified miR-21-3p and miR-27a-5p to be induced 4-fold and 3-fold, respectively in response to OX-PAPC treatment compared to control treatment in HAECs. To identify the targets, we performed whole genome transcript profiling following transient over-expression of these two miRNAs followed by. In total, 1254 genes were down-regulated with 925 of them overlapping between the two miRNAs. Functional enrichment analysis using Gene Ontology predicted that the two miRNAs were involved in the regulation of NF-κB signaling. We characterized the Toll/interleukin-1 receptor (TIR) domain-containing adaptor protein TICAM2 as a direct target of miR-21-3p and miR-27a-5p. Furthermore, we showed that over-expression of miR-21-3p and miR-27a-5p lead to decreased p65 translocation to the nucleus and decreased the expression of known NF-κB downstream target genes confirming both miRNAs’ role in negatively regulating NF-κB signaling in endothelial cells. mRNA expression profiling of human aortic endothelial cells from two separate donors that were transfected with 1 nM microRNA mimics and negative control. The miRIDIAN mimics used were miR-21-3p (Catalog Number:C-301023-01-0005), miR-27a-5p (Catalog No: C-301028-01-0005), negative control (Catalog No: CN-001000-01-05)
Project description:This is a prospective-retrospective study to determine if the expression of the miRNA’s miR-31-3p and miR-31-5p are prognostic of patient outcomes or predictive of the benefit from anti-EGFR therapy in stage III Colon Cancer. The present study will utilize FFPE tumor samples collected from patients enrolled in the PETACC-8 study conducted by the Fédération Francophone de Cancérologie Digestive (FFCD). This phase 3 clinical trial prospectively randomized fully resected stage III colon cancer patients to receive adjuvant treatment with either FOLFOX-4 plus cetuximab or FLOFOX-4 alone.
Project description:The transition of the endothelium to a pro-inflammatory state is key to progression of chronic inflammatory diseases including rheumatoid arthritis, chronic bowel disease and atherosclerosis. In atherosclerosis it is hypothesized that low density lipoproteins (LDL) that become trapped in the intima of the blood vessels are oxidized to minimally modified LDL (mmLDL) and that these serve as an important contributing factors to endothelial dysfunction. Oxidized 1-palmitoyl-2-arachidonoyl-sn-glycero-3-phosphatidylcholine (OX-PAPC), a model of the active phospholipid components of mmLDL affects the expression of hundreds of genes involved in inflammatory and other biological processes in human aortic endothelial cells (HAECs). We hypothesized that microRNAs (miRNAs) partially regulate this response. Using next generation sequencing, we identified miR-21-3p and miR-27a-5p to be induced 4-fold and 3-fold, respectively in response to OX-PAPC treatment compared to control treatment in HAECs. To identify the targets, we performed whole genome transcript profiling following transient over-expression of these two miRNAs followed by. In total, 1254 genes were down-regulated with 925 of them overlapping between the two miRNAs. Functional enrichment analysis using Gene Ontology predicted that the two miRNAs were involved in the regulation of NF-κB signaling. We characterized the Toll/interleukin-1 receptor (TIR) domain-containing adaptor protein TICAM2 as a direct target of miR-21-3p and miR-27a-5p. Furthermore, we showed that over-expression of miR-21-3p and miR-27a-5p lead to decreased p65 translocation to the nucleus and decreased the expression of known NF-κB downstream target genes confirming both miRNAs’ role in negatively regulating NF-κB signaling in endothelial cells.
Project description:MiRNAs have been shown to alter both protein expression and secretion in different cellular contexts. By combining in vitro, in vivo and in silico techniques, we demonstrated that overexpression of pre-miR-1307 reduced the ability of breast cancer cells to induce endothelial cell sprouting and angiogenesis. However, the molecular mechanism behind this and the effect of the individual mature miRNAs derived from pre-miR-1307 on protein secretion and is largely unknown. Here, we overexpressed miR-1307-3p|0, -3p|1 and 5p|0 in MDA-MB-231 breast cancer cells and assessed the impact of miRNA overexpression on protein secretion by Mass Spectrometry. Unsupervised hierarchical clustering revealed a distinct phenotype induced by overexpression of miR-1307-5p|0 compared to the controls and to the 5’isomiRs derived from the 3p-arm. Together, our results suggest different impacts of miR-1307-3p and miR-1307-5p on protein secretion which is in line with our in vitro observation that miR-1307-5p, but not the isomiRs derived from the 3p-arm reduce endothelial cell sprouting in vitro. Hence these data support the hypothesis that miR-1307-5p is at least partly responsible for impaired vasculature in tumors overexpressing pre-miR-1307.
Project description:We used single cell RNA sequencing (scRNA-seq) to analyze the transcriptional diversity of cells undergoing adipogenesis using two cellular models of adipogenesis in vitro, human SGBS cells and murine 3T3-L1 cells.
Project description:Whole transcriptome Identification of direct targets of miR-23b and miR-27a using biotinylated pull-downs found that both miRNAs have roles relevant to the mammalian cell cycle and cancer.