title: Diabetes impairs stem cell and proangiogenic cell mobilization in humans.
abstract: OBJECTIVE
  Diabetes mellitus (DM) increases cardiovascular risk, at least in part, through shortage of vascular regenerative cells derived from the bone marrow (BM). In experimental models, DM causes morphological and functional BM alterations, but information on BM function in human DM is missing. Herein, we sought to assay mobilization of stem and proangiogenic cells in subjects with and without DM.
  
  
  METHODS
  In a prospective trial (NCT01102699), we tested BM responsiveness to 5 μg/kg human recombinant granulocyte colony-stimulating factor (hrG-CSF) in 24 individuals with DM (10 type 1 and 14 type 2) and 14 individuals without DM. Before and 24 h after hrG-CSF, we quantified circulating stem/progenitor cells and total and differential white blood cell counts. We also evaluated in vivo the proangiogenic capacity of peripheral blood mononuclear cells using the Matrigel plug assay.
  
  
  RESULTS
  In response to hrG-CSF, levels of CD34(+) cells and other progenitor cell phenotypes increased in subjects without DM. Patients with DM had significantly impaired mobilization of CD34(+), CD133(+), and CD34(+)CD133(+) hematopoietic stem cells and CD133(+)KDR(+) endothelial progenitors, independently of potential confounders. The in vivo angiogenic capacity of peripheral blood mononuclear cells significantly increased after hrG-CSF in control subjects without DM, but not in patients with DM. DM was also associated with the inability to upregulate CD26/DPP-4 on CD34(+) cells, which is required for the mobilizing effect of granulocyte colony-stimulating factor.
  
  
  CONCLUSIONS
  Stem and proangiogenic cell mobilization in response to hrG-CSF is impaired in DM, possibly because of maladaptive CD26/DPP-4 regulation. These alterations may hamper tissue repair and favor the development of cardiovascular complications.
authors.affiliation: Department of Medicine, University of Padova, Padova, Italy. gianpaolofadini@hotmail.com
authors.forename: Gian Paolo
authors.initials: GP
authors.lastname: Fadini
authors.forename: Mattia
authors.initials: M
authors.lastname: Albiero
authors.forename: Saula
authors.initials: S
authors.lastname: Vigili de Kreutzenberg
authors.forename: Elisa
authors.initials: E
authors.lastname: Boscaro
authors.forename: Roberta
authors.initials: R
authors.lastname: Cappellari
authors.forename: Mariacristina
authors.initials: M
authors.lastname: Marescotti
authors.forename: Nicol
authors.initials: N
authors.lastname: Poncina
authors.forename: Carlo
authors.initials: C
authors.lastname: Agostini
authors.forename: Angelo
authors.initials: A
authors.lastname: Avogaro
mesh_terms: D000328:Adult; D018952:Antigens, CD34 / Q000378:metabolism; D003922:Diabetes Mellitus, Type 1 / Q000503:physiopathology*; D003924:Diabetes Mellitus, Type 2 / Q000503:physiopathology*; D005260:Female; D000069585:Filgrastim; D005434:Flow Cytometry; D016179:Granulocyte Colony-Stimulating Factor / Q000494:pharmacology; D006412:Hematopoietic Stem Cells / Q000166:cytology* / Q000187:drug effects; D006801:Humans; D008297:Male; D008875:Middle Aged; D011994:Recombinant Proteins / Q000494:pharmacology; D013234:Stem Cells / Q000166:cytology* / Q000187:drug effects
chemical_list: D018952:Antigens, CD34; D011994:Recombinant Proteins; D016179:Granulocyte Colony-Stimulating Factor; D000069585:Filgrastim