title: Deregulation of microRNA-503 contributes to diabetes mellitus-induced impairment of endothelial function and reparative angiogenesis after limb ischemia.
abstract: BACKGROUND
  Diabetes mellitus impairs endothelial cell (EC) function and postischemic reparative neovascularization by molecular mechanisms that are not fully understood. microRNAs negatively regulate the expression of target genes mainly by interaction in their 3' untranslated region.
  
  
  RESULTS
  We found that microRNA-503 (miR-503) expression in ECs is upregulated in culture conditions mimicking diabetes mellitus (high D-glucose) and ischemia-associated starvation (low growth factors). Under normal culture conditions, lentivirus-mediated miR-503-forced expression inhibited EC proliferation, migration, and network formation on Matrigel (comparisons versus lentivirus.GFP control). Conversely, blocking miR-503 activity by either adenovirus-mediated transfer of a miR-503 decoy (Ad.decoymiR-503) or by antimiR-503 (antisense oligonucleotide) improved the functional capacities of ECs cultured under high D-glucose/low growth factors. We identified CCNE1 and cdc25A as direct miR-503 targets which are downregulated by high glucose/low growth factors in ECs. Next, we obtained evidence that miR-503 expression is increased in ischemic limb muscles of streptozotocin-diabetic mice and in ECs enriched from these muscles. Moreover, Ad.decoymiR-503 delivery to the ischemic adductor of diabetic mice corrected diabetes mellitus-induced impairment of postischemic angiogenesis and blood flow recovery. We finally investigated miR-503 and target gene expression in muscular specimens from the amputated ischemic legs of diabetic patients. As controls, calf biopsies of nondiabetic and nonischemic patients undergoing saphenous vein stripping were used. In diabetic muscles, miR-503 expression was remarkably higher, and it inversely correlated with cdc25 protein expression. Plasma miR-503 levels were also elevated in the diabetic individuals.
  
  
  CONCLUSIONS
  Our data suggest miR-503 as a possible therapeutic target in diabetic patients with critical limb ischemia.
authors.affiliation: Regenerative Medicine, School of Clinical Medicine, University of Bristol, Bristol, England, UK. c.emanueli@yahoo.co.uk
authors.forename: Andrea
authors.initials: A
authors.lastname: Caporali
authors.forename: Marco
authors.initials: M
authors.lastname: Meloni
authors.forename: Christine
authors.initials: C
authors.lastname: Völlenkle
authors.forename: Desiree
authors.initials: D
authors.lastname: Bonci
authors.forename: Graciela B
authors.initials: GB
authors.lastname: Sala-Newby
authors.forename: Roberta
authors.initials: R
authors.lastname: Addis
authors.forename: Gaia
authors.initials: G
authors.lastname: Spinetti
authors.forename: Sergio
authors.initials: S
authors.lastname: Losa
authors.forename: Rachel
authors.initials: R
authors.lastname: Masson
authors.forename: Andrew H
authors.initials: AH
authors.lastname: Baker
authors.forename: Reuven
authors.initials: R
authors.lastname: Agami
authors.forename: Carlos
authors.initials: C
authors.lastname: le Sage
authors.forename: Gianluigi
authors.initials: G
authors.lastname: Condorelli
authors.forename: Paolo
authors.initials: P
authors.lastname: Madeddu
authors.forename: Fabio
authors.initials: F
authors.lastname: Martelli
authors.forename: Costanza
authors.initials: C
authors.lastname: Emanueli
mesh_terms: D000818:Animals; D001706:Biopsy; D002478:Cells, Cultured; D003921:Diabetes Mellitus, Experimental / Q000235:genetics / Q000473:pathology / Q000503:physiopathology; D042783:Endothelial Cells / Q000166:cytology / Q000502:physiology; D005121:Extremities / Q000098:blood supply; D015870:Gene Expression / Q000502:physiology; D005947:Glucose / Q000494:pharmacology; D006801:Humans; D036341:Intercellular Signaling Peptides and Proteins / Q000494:pharmacology; D007511:Ischemia / Q000235:genetics / Q000473:pathology / Q000503:physiopathology; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D035683:MicroRNAs / Q000502:physiology*; D018482:Muscle, Skeletal / Q000473:pathology / Q000502:physiology; D018919:Neovascularization, Physiologic / Q000502:physiology*; D014471:Umbilical Veins / Q000166:cytology; D020687:cdc25 Phosphatases / Q000235:genetics
chemical_list: D036341:Intercellular Signaling Peptides and Proteins; C545473:MIRN503 microRNA, human; D035683:MicroRNAs; C556275:Mirn503 microRNA, mouse; C517004:CDC25A protein, human; C517005:Cdc25a protein, mouse; D020687:cdc25 Phosphatases; D005947:Glucose