Cells release extracellular vesicles (EVs) of different sizes. Small EVs (< 200 nm) can originate from the fusion of multivesicular bodies with the plasma membrane, i.e.
View Article and Find Full Text PDFExosomes are a type of extracellular vesicle released from cells after fusion of multivesicular bodies with the plasma membrane. These vesicles are often enriched in cholesterol, SM, glycosphingolipids, and phosphatidylserine. Lipids not only have a structural role in exosomal membranes but also are essential players in exosome formation and release to the extracellular environment.
View Article and Find Full Text PDFThe aim of this study was to identify microRNAs in urinary exosomes that are differently expressed in prostate cancer patients and healthy donors. For this purpose, RNA was extracted from urinary exosomes from 20 prostate cancer patients and 9 healthy males and the microRNAs were analyzed by next generation sequencing. Interestingly, 5 microRNAs - miR-196a-5p, miR-34a-5p, miR-143-3p, miR-501-3p and miR-92a-1-5p - were significantly downregulated in exosomes from prostate cancer patients.
View Article and Find Full Text PDFExosomes are nanosized membrane vesicles released by fusion of an organelle of the endocytic pathway, the multivesicular body, with the plasma membrane. This process was discovered more than 30 years ago, and during these years, exosomes have gone from being considered as cellular waste disposal to mediate a novel mechanism of cell-to-cell communication. The exponential interest in exosomes experienced during recent years is due to their important roles in health and disease and to their potential clinical application in therapy and diagnosis.
View Article and Find Full Text PDFLittle is known about olfactory glands' regulation despite their presumed importance for normal functioning of the cilia of olfactory neurons. The aim of this study was to establish an assay for olfactory gland activation by using large-scale quantitative electron microscopy (EM). In addition we wanted to test the hypothesis that cholinergic drugs activate the olfactory glands, by using our newly established EM assay.
View Article and Find Full Text PDFExosomes are vesicles released from cells by fusion of multivesicular bodies (MVBs) with the plasma membrane. This study aimed to investigate whether the phosphoinositide kinase PIKfyve affects this process. Our results show that in PC-3 cells inhibition of PIKfyve by apilimod or depletion by siRNA increased the secretion of the exosomal fraction.
View Article and Find Full Text PDFExosomes are vesicles released by cells after fusion of multivesicular bodies with the plasma membrane. In this study, we have investigated whether ether lipids affect the release of exosomes in PC-3 cells. To increase the cellular levels of ether lipids, the ether lipid precursor hexadecylglycerol was added to cells.
View Article and Find Full Text PDFExosomes are released by cells after fusion of multivesicular bodies with the plasma membrane. The molecular mechanism of this process is still unclear. We investigated the role of sphingolipids and flotillins, which constitute a raft-associated family of proteins, in the release of exosomes.
View Article and Find Full Text PDFmiRNAs are small non-coding RNAs that finely regulate gene expression in cells. Alterations in miRNA expression have been associated with development of cancer, and miRNAs are now being investigated as biomarkers for cancer as well as other diseases. Recently, miRNAs have been found outside cells in body fluids.
View Article and Find Full Text PDFBiochim Biophys Acta
February 2013
Exosomes are small extracellular vesicles released to the extracellular milieu through fusion of multivesicular bodies with the plasma membrane. These vesicles contain microRNAs and might therefore be vehicles transferring genetic information between cells. The aim of this study was to investigate whether there was a sorting of microRNAs into exosomes in the prostate cancer cell line PC-3.
View Article and Find Full Text PDFDevelopment of insulin resistance is positively associated with dietary saturated fatty acids and negatively associated with monounsaturated fatty acids. To clarify aspects of this difference we have compared the metabolism of oleic (OA, monounsaturated) and palmitic acids (PA, saturated) in human myotubes. Human myotubes were treated with 100μM OA or PA and the metabolism of [(14)C]-labeled fatty acid was studied.
View Article and Find Full Text PDFThe aim of this study was to explore the effects of 22(S)-hydroxycholesterol (22(S)-HC) on lipid and glucose metabolism in human-derived cells from metabolic active tissues. Docking of T0901317 and 22(S)-HC showed that both substances fitted into the ligand binding domain of liver X receptors (LXR). Results show that while several lipogenic genes were induced by T0901317 in myotubes, HepG2 cells and SGBS cells, effect of 22(S)-HC varied more between cell types.
View Article and Find Full Text PDFSkeletal muscle of insulin resistant individuals is characterized by lower fasting lipid oxidation and reduced ability to switch between lipid and glucose oxidation. The purpose of the present study was to examine if chronic hyperglycemia would impair metabolic switching of myotubes. Human myotubes were treated with or without chronic hyperglycemia (20mmol/l glucose for 4 days), and metabolism of [(14)C]oleic acid (OA) and [(14)C]glucose was studied.
View Article and Find Full Text PDFObesity and insulin resistance are related to both enlarged intramyocellular triacylglycerol stores and accumulation of lipid intermediates. We investigated how lipid overflow can change the oxidation of intramyocellular lipids (ICL(OX)) and intramyocellular lipid storage (ICL). These experiments were extended by comparing these processes in primary cultured myotubes established from healthy lean and obese type 2 diabetic (T2D) individuals, two extremes in a range of metabolic phenotypes.
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