Project description:Exosomes which are nano-vesicles and released from living cells, have attracted more attention as an important mediator for cell-to-cell communication. Given that obesity often causes insulin resistance, it is significant to test whether exosomes derived from obesity adipose tissue possess any capacity in regulating insulin sensitivity. In this study we purified exosomes from the adipose tissue. Exosomes derived from ob/ob mice (Ob-exosomes) and B6 mice fed a high-fat diet (HFD-exosomes) displayed similar size and molecular maker to those originated from the normal B6 mice (WT-exosomes), but their regulatory role in insulin sensitivity was opposite. Abundant exosomal miRNAs were detected by the Next Generation Sequencing. Ob-exosomes encapsulated the lower levels of miR-141-3p compared to WT-exosomes, furthermore, miR-141-3p can be effectively delivered into AML12 cells accompanied by the absorption of Ob-exosomes and WT-exosomes. But the absorption of miR-141-3p from adipose tissues to AML12 cells could be blocked by GW4869, an inhibitor of exosome biogenesis and release. Importantly, the exosomal miR-141-3p functionally down-regulated its target gene Pten expression in AML12 cells, and the knockdown of miR-141-3p inhibited the insulin response and glucose uptake in AML12 cells, however Ob-exosomes-mediated inhibitory effects on insulin function disappeared after overexpression of miR-141-3p. These data indicate that the absorption of exosomes released from obesity adipose tissue including lower level of miR-141-3p than healthy adipose tissue into hepatocytes can significantly inhibit the insulin sensitivity and glucose uptake. Thus, our study may certify a novel mechanism that the secretion of “harmful” exosomes from obesity adipose tissues cause insulin resistance.
Project description:Exosomes, the nano-vesicles released from living cells, were the important mediator for cell-to-cell communication. In order to clarify whether the exosomes derived from obesity adipose tissue mediate insulin resistance of hepatocytes, we extract the exosomes from the adipose tissue of different mice models. Exosomes derived from ob/ob mice (Ob-exosomes), B6 mice fed with a high-fat diet (HFD-exosomes) and normal B6 mice (WT-exosomes) displayed similar size and molecular makers, but their effect on the insulin sensitivity of hepatocytes were obviously different or opposite. Abundant exosomal miRNAs in Ob-, HFD- and WT-exosomes were detected by the Next Generation Sequencing. The levels of miR-141-3p in Ob- and HFD-exosomes were significantly lower than WT-exosomes. MiR-141-3p can be effectively delivered into AML12 cells accompanied by the absorption of exosomes, but the absorption of miR-141-3p into AML12 cells could be blocked by GW4869, an inhibitor of exosome biogenesis and release. Importantly, the Ob-exosomes or miR-141-3p knockdown in WT--exosomes obviously inhibited the insulin response and glucose uptake of AML12 cells, however, the inhibitory effects on insulin function disappeared after the overexpression of miR-141-3p in Ob-exosomes or AML12 cells. The effects of miR-141-3p on insulin function could be achieved by improving the level of phosphorylation of AKT and enhancing insulin signal transduction. Therefore, the absorption of hepatocytes for exosomes released from obesity adipose tissue containing less miR-141-3p than healthy adipose tissue can significantly inhibit the insulin sensitivity and glucose uptake. Our study may certify a novel mechanism that the secretion of "harmful" exosomes from obesity adipose tissues cause insulin resistance.
Project description:To elucidate whether exosomal hsa-miR199a-3p plays a role in neuroblastoma tumorigenesis, a miRNA-seq analysis on plasma exosomal miRNA from neuroblastoma patients and normal controls.
Project description:Corneal epithelial RCE1(5T5) cells follow a sequential process that leads to the formation of a 4-5 layered stratified epithelium with a gene expression pattern similar to that shown in primary cultures of corneal epithelial cells. We have previously identified three different developmental stages during the differentiation of the rabbit corneal epithelial cell line RCE1(5T5). In this analysis we describe the participation of miR-141-3p as a regulator of the proliferative phenotype and its participation on maintaining differentiation of corneal eptihelial cells.
Project description:To identify putative novel specific targets of miR-141-3p, we overexpressed this miRNAs in primary keratinocytes using a synthetic mimic (pre-miR-141-3p) or a synthetic “negative” control mimic (pre-miR-ctrl). RNA samples were harvested 30 hours post-transfection and 3 independent experiments were carried out.
Project description:Exosomes are small extracellular nano-vesicles of endocytic origin that mediate different signals between cells, by surface interactions and by shuttling of functional RNA from one cell to another. In this study, we show that exosomes, produced by mouse mast cells exposed to oxidative stress, change their mRNA content and also that these exosomes can influence the response of other cells to oxidative stress by providing recipient cells with a resistance against oxidative stress. Finally, we also show that UV-light affect the biological functions associated with exosomes released under oxidative stress. These results argue that exosomal shuttle of RNA is involved in cell-to-cell communication, by influencing the response of recipient cells to an external stimulus. We used microarrays to detail to examine the gene expression underlying the effect of H2O2 on the exosomal RNA and how exosomes isolated from oxidative stress influence the growth of recipient cells during oxidative stress. The mRNA content of the exosomes from normal conditions (MC9 Exo_norm) were compared to that from exosomes from H2O2 conditions (MC9 Exo_H2O2). The mRNA content of recipient cells MC9 were identified before (MC9 cells_norm) and after (MC9 cells_H2O2) addition of exosomes that were isolated from normal and H2O2 conditions.
Project description:This study aimed to elucidate the role of microRNA miR-92a-3p in the pathogenesis of adenomyosis. We focused on understanding how miR-92a-3p in exosomes derived from ectopic lesions influences the behavior of endometrial cells, DRG neurons, and Human Umbilical Vein Endothelial Cells (HUVECs), and its potential as a non-invasive diagnostic biomarker. Our findings revealed that MiR-92a-3p is significantly upregulated in exosomes derived from ectopic lesions of adenomyosis. This upregulation was associated with enhanced migration and invasion capabilities in eutopic endometrial cells, DRG neurons, and HUVECs. Furthermore, the study demonstrated a significant correlation between the levels of MiR-92a-3p in urinary exosomes and the clinical symptoms of adenomyosis, suggesting its potential as a non-invasive biomarker for the disease. This study elucidates an exosomal signaling process via miR-92a-3p that drives pathological infiltration and angiogenesis to promote adenomyosis progression. Upregulated miR-92a-3p in biofluid exosomes shows promising non-invasive biomarker potential for diagnosis and monitoring of this disease. Our findings unveil novel targets and tools for improved clinical management.