title: Obesity reduces the pro-angiogenic potential of adipose tissue stem cell-derived extracellular vesicles (EVs) by impairing miR-126 content: impact on clinical applications.
abstract: OBJECTIVE
  Soluble factors and cell-derived extracellular vesicles (EVs) are crucial tissue repair mediators in cell-based therapy. In the present study, we investigate the therapeutic impact of EVs released by adipose tissue-derived stem cells (ASCs) recovered from obese subjects' visceral and subcutaneous tissues.
  
  
  METHODS
  ASCs were recovered from 10 obese (oASCs) and 6 non-obese (nASCs) participants and characterized. In selected experiments, nASCs and oASCs were cultured with palmitic acid (PA) or high glucose (HG), respectively. EVs from obese (oEVs) and non-obese (nEVs) subjects' visceral and subcutaneous ASCs were collected after ultracentrifugation and analyzed for their cargo: microRNA-126 (miR-126), vascular endothelial growth factor (VEGF), and matrix metalloproteinase 2 (MMP-2), and for their biological effects on endothelial cells (ECs). Western blotting analysis and loss- and gain-of function experiments were performed.
  
  
  RESULTS
  oEVs show impaired angiogenic potential compared with nEVs. This effect depends on EV cargo: reduced content of VEGF, MMP-2 and, more importantly, miR-126. We demonstrate, using gain- and loss-of-function experiments, that this reduced miR-126 content leads to Spred1 upregulation and the inhibition of the extracellular signal-regulated kinase 1/2 mitogen-activated protein kinase pathway in ECs. We also show that PA treatment of nASCs translates into the release of EVs that recapitulate oEV cargo. Moreover, HG treatment of oASCs further reduces miR-126 EV content and EV-mediated in vitro angiogenesis. Finally, impaired pro-angiogenic potential is also detected in EVs released from obese subcutaneous adipose tissue-derived ASCs.
  
  
  CONCLUSIONS
  These results indicate that obesity impacts on EV pro-angiogenic potential and may raise concerns about the use of adipose tissue-derived EVs in cell-based therapy in the obese setting.
authors.affiliation: Department of Medical Sciences, University of Torino, Torino, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Togliatto
authors.affiliation: Department of Medical Sciences, University of Torino, Torino, Italy.
authors.forename: P
authors.initials: P
authors.lastname: Dentelli
authors.affiliation: Department of Medical Sciences, University of Torino, Torino, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Gili
authors.affiliation: Department of Medical Sciences, University of Torino, Torino, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Gallo
authors.affiliation: Department of Medical Sciences, University of Torino, Torino, Italy.
authors.forename: C
authors.initials: C
authors.lastname: Deregibus
authors.affiliation: Department of Medical Sciences, University of Torino, Torino, Italy.
authors.forename: E
authors.initials: E
authors.lastname: Biglieri
authors.affiliation: Department of Medical Sciences, University of Torino, Torino, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Iavello
authors.affiliation: Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy.
authors.forename: E
authors.initials: E
authors.lastname: Santini
authors.affiliation: Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy.
authors.forename: C
authors.initials: C
authors.lastname: Rossi
authors.affiliation: Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Solini
authors.affiliation: Department of Medical Sciences, University of Torino, Torino, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Camussi
authors.affiliation: Department of Medical Sciences, University of Torino, Torino, Italy.
authors.forename: M F
authors.initials: MF
authors.lastname: Brizzi
mesh_terms: D050156:Adipogenesis / Q000187:drug effects; D053687:Adult Stem Cells / Q000187:drug effects / Q000378:metabolism* / Q000473:pathology*; D002454:Cell Differentiation / Q000187:drug effects; D002478:Cells, Cultured; D042783:Endothelial Cells / Q000378:metabolism / Q000473:pathology; D000067128:Extracellular Vesicles / Q000378:metabolism*; D006801:Humans; D050152:Intra-Abdominal Fat / Q000378:metabolism / Q000473:pathology; D035683:MicroRNAs / Q000378:metabolism*; D055806:Microvessels / Q000378:metabolism*; D009765:Obesity / Q000378:metabolism* / Q000473:pathology* / Q000503:physiopathology; D050151:Subcutaneous Fat / Q000166:cytology* / Q000378:metabolism / Q000473:pathology; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism
chemical_list: C527111:MIRN126 microRNA, human; D035683:MicroRNAs; D042461:Vascular Endothelial Growth Factor A