title: Decreased number and impaired functionality of endothelial progenitor cells in subjects with metabolic syndrome: implications for increased cardiovascular risk.
abstract: OBJECTIVE
  Metabolic syndrome (MetS) is characterized by low-grade inflammation and confers an increased risk for cardiovascular disease. Endothelial progenitor cells (EPCs) are a measure of vascular health and are decreased in patients with various risk factors for cardiovascular disease (CVD). There is a paucity of data examining the EPC status especially in terms of their functionality in MetS subjects without diabetes or cardiovascular disease. We aimed to enumerate and functionally characterize EPCs in subjects with MetS in comparison to healthy controls.
  
  
  METHODS
  The study was performed at the University of California Davis Medical Center. Healthy controls (n=31) and MetS (n=46) subjects were included in the study. EPCs were enumerated in fasting blood by KDR/CD34 dual positivity. Functionality was assessed by the colony forming units (CFU) assay, migration and tubule formation.
  
  
  RESULTS
  Subjects with MetS had significantly decreased number of EPCs compared to control subjects. Furthermore, EPCs from MetS subjects depicted significantly impaired clonogenic capacity, i.e., decreased colony forming units, and impaired capacity to incorporate into tubular structures suggesting functional impairment of EPCs from MetS subjects.
  
  
  CONCLUSIONS
  We make the novel observation that MetS subjects without diabetes or CVD have decreased EPC number and impaired functionality as compared to control subjects. These findings could contribute to the increased CV risk in this population.
authors.affiliation: The Laboratory for Atherosclerosis and Metabolic Research, Department of Medical Pathology and Laboratory Medicine, UC Davis Medical Center, Sacramento, CA 95817, USA. ijalal@ucdavis.edu
authors.forename: I
authors.initials: I
authors.lastname: Jialal
authors.forename: S
authors.initials: S
authors.lastname: Devaraj
authors.forename: U
authors.initials: U
authors.lastname: Singh
authors.forename: B A
authors.initials: BA
authors.lastname: Huet
mesh_terms: D000328:Adult; D000368:Aged; D002318:Cardiovascular Diseases / Q000209:etiology*; D002452:Cell Count; D054443:Cell Migration Assays; D003114:Colony-Forming Units Assay; D042783:Endothelial Cells / Q000378:metabolism*; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D008297:Male; D024821:Metabolic Syndrome / Q000503:physiopathology*; D008875:Middle Aged; D012307:Risk Factors; D013234:Stem Cells / Q000378:metabolism*