title: Isolation, characterization and potential role in beta cell-endothelium cross-talk of extracellular vesicles released from human pancreatic islets.
abstract: The cross-talk between beta cells and endothelium plays a key role in islet physiopathology and in the revascularization process after islet transplantation. However, the molecular mechanisms involved in this cross-talk are not fully elucidated. Extracellular vesicles (EVs) are secreted membrane nanoparticles involved in inter-cellular communication through the transfer of proteins and nucleic acids. The aims of this study were: 1) isolation and characterization of EVs from human islets; 2) evaluation of the pro-angiogenic effect of islet-derived EVs on human islet endothelial cells (IECs). EVs were isolated by ultracentrifugation from conditioned medium of human islets and characterized by nanotrack analysis (Nanosight), FACS, western blot, bioanalyzer, mRNA/microRNA RT-PCR array. On IECs, we evaluated EV-induced insulin mRNA transfer, proliferation, resistance to apoptosis, in vitro angiogenesis, migration, gene and protein profiling. EVs sized 236±54 nm, expressed different surface molecules and islet-specific proteins (insulin, C-peptide, GLP1R) and carried several mRNAs (VEGFa, eNOS) and microRNAs (miR-27b, miR-126, miR-130 and miR-296) involved in beta cell function, insulin secretion and angiogenesis. Purified EVs were internalized into IECs inducing insulin mRNA expression, protection from apoptosis and enhancement of angiogenesis. Human islets release biologically active EVs able to shuttle specific mRNAs and microRNAs (miRNAs) into target endothelial cells. These results suggest a putative role for islet-derived EVs in beta cell-endothelium cross-talk and in the neoangiogenesis process which is critical for engraftment of transplanted islets.
authors.affiliation: Department of Medical Sciences, University of Torino, Torino, Italy.
authors.forename: Federico
authors.initials: F
authors.lastname: Figliolini
authors.affiliation: Department of Medical Sciences, University of Torino, Torino, Italy.
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Cantaluppi
authors.affiliation: Department of Medical Sciences, University of Torino, Torino, Italy.
authors.forename: Michela
authors.initials: M
authors.lastname: De Lena
authors.affiliation: Department of Medical Sciences, University of Torino, Torino, Italy.
authors.forename: Silvia
authors.initials: S
authors.lastname: Beltramo
authors.affiliation: Liver Transplantation Center, University of Torino, Torino, Italy.
authors.forename: Renato
authors.initials: R
authors.lastname: Romagnoli
authors.affiliation: Liver Transplantation Center, University of Torino, Torino, Italy.
authors.forename: Mauro
authors.initials: M
authors.lastname: Salizzoni
authors.affiliation: Diabetes Research Institute (HSR-DRI), San Raffaele Scientific Institute, Milano, Italy.
authors.forename: Raffaella
authors.initials: R
authors.lastname: Melzi
authors.affiliation: Diabetes Research Institute (HSR-DRI), San Raffaele Scientific Institute, Milano, Italy.
authors.forename: Rita
authors.initials: R
authors.lastname: Nano
authors.affiliation: Diabetes Research Institute (HSR-DRI), San Raffaele Scientific Institute, Milano, Italy.
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Piemonti
authors.affiliation: Fresenius Medical Care, Bad Homburg, Germany.
authors.forename: Ciro
authors.initials: C
authors.lastname: Tetta
authors.affiliation: Department of Medical Sciences, University of Torino, Torino, Italy.
authors.forename: Luigi
authors.initials: L
authors.lastname: Biancone
authors.affiliation: Department of Medical Sciences, University of Torino, Torino, Italy.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Camussi
mesh_terms: D043925:Angiogenesis Inducing Agents / Q000378:metabolism*; D015153:Blotting, Western; D002450:Cell Communication / Q000502:physiology*; D042783:Endothelial Cells / Q000166:cytology / Q000502:physiology*; D005434:Flow Cytometry; D006801:Humans; D050417:Insulin-Secreting Cells / Q000502:physiology*; D035683:MicroRNAs / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D020239:Receptor Cross-Talk / Q000502:physiology*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D022161:Transport Vesicles / Q000378:metabolism*
chemical_list: D043925:Angiogenesis Inducing Agents; D035683:MicroRNAs; D012333:RNA, Messenger