title: Aging, exercise, and endothelial progenitor cell clonogenic and migratory capacity in men.
abstract: Numerical and functional impairment of circulating endothelial progenitor cells (EPCs) is thought to contribute to vascular aging and the associated increase in cardiovascular risk. We tested the following hypotheses: 1) EPC clonogenic and migratory capacity decrease progressively with age in healthy, sedentary adult men; and 2) regular aerobic exercise will improve EPC clonogenic and migratory capacity in previously sedentary middle-aged and older men. Peripheral blood samples were collected from 46 healthy sedentary men: 10 young (26 +/- 1 yr), 15 middle-aged (47 +/- 1 yr), and 21 older (63 +/- 1 yr). Mononuclear cells were isolated and preplated for 2 days, and nonadherent cells were further cultured for 7 days to determine EPC colony-forming units. Migratory activity of EPCs was determined using a modified Boyden chamber. Ten sedentary middle-aged and older men (59 +/- 3 yr) were studied before and after a 3-mo aerobic exercise intervention. The number of EPC colony-forming units was approximately 75% lower (P < 0.01) in middle-aged (12 +/- 3) and older (8 +/- 2) compared with young (40 +/- 7) men. There was no difference in colony count between middle-aged and older men. EPC migration (fluorescent units) was significantly reduced in older (453 +/- 72) compared with young (813 +/- 114) and middle-aged (760 +/- 114) men. The exercise intervention increased (P < 0.05) both EPC colony-forming units (10 +/- 3 to 22 +/- 5) and migratory activity (683 +/- 96 to 1,022 +/- 123) in previously sedentary middle-aged and older men. These results provide further evidence that aging adversely affects EPC function. Regular aerobic-endurance exercise, however, is an effective lifestyle intervention strategy for improving EPC clonogenic and migratory capacity in middle-aged and older healthy men.
authors.affiliation: Integrative Vascular Biology Laboratory, Dept. of Integrative Physiology, University of Colorado, Boulder, CO 80309, USA.
authors.forename: Greta L
authors.initials: GL
authors.lastname: Hoetzer
authors.forename: Gary P
authors.initials: GP
authors.lastname: Van Guilder
authors.forename: Heather M
authors.initials: HM
authors.lastname: Irmiger
authors.forename: Rebecca S
authors.initials: RS
authors.lastname: Keith
authors.forename: Brian L
authors.initials: BL
authors.lastname: Stauffer
authors.forename: Christopher A
authors.initials: CA
authors.lastname: DeSouza
mesh_terms: D000328:Adult; D053687:Adult Stem Cells / Q000502:physiology*; D000368:Aged; D000375:Aging / Q000502:physiology*; D002465:Cell Movement / Q000502:physiology*; D049109:Cell Proliferation; D003114:Colony-Forming Units Assay; D003430:Cross-Sectional Studies; D015444:Exercise / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged