Circulating hematopoietic progenitor cells in runners.
Because endurance exercise causes release of mediators and growth factors active on the bone marrow, we asked whether it might affect circulating hematopoietic progenitor cells (HPCs) in amateur runners [n = 16, age: 41.8 +/- 13.5 (SD) yr, training: 93.8 +/- 31.8 km/wk] compared with sedentary controls (n = 9, age: 39.4 +/- 10.2 yr). HPCs, plasma cortisol, interleukin (IL)-6, granulocyte colony-stimulating factor (G-CSF), and the growth factor fms-like tyrosine kinase-3 (flt3)-ligand were measured at rest and after a marathon (M; n = 8) or half-marathon (HM; n = 8). Circulating HPC counts (i.e., CD34(+) cells and their subpopulations) were three- to fourfold higher in runners than in controls at baseline. They were unaffected by HM or M acutely but decreased the morning postrace. Baseline cortisol, flt3-ligand, IL-6, and G-CSF levels were similar in runners and controls. IL-6 and G-CSF increased to higher levels after M compared with HM, whereas cortisol and flt3-ligand increased similarly postrace. Our data suggest that increased HPCs reflect an adaptation response to recurrent, exercise-associated release of neutrophils and stress and inflammatory mediators, indicating modulation of bone marrow activity by habitual running.
Bonsignore
Maria R
MR
Institute of Respiratory Pathophysiology, National Research Council, 90146 Palermo, Italy. marisa@ifr.pa.cnr.it
Morici
Giuseppe
G
Santoro
Alessandra
A
Pagano
Maria
M
Cascio
Lucia
L
Bonanno
Anna
A
Abate
Pietro
P
Mirabella
Franco
F
Profita
Mirella
M
Insalaco
Giuseppe
G
Gioia
Maria
M
Vignola
A Maurizio
AM
Majolino
Ignazio
I
Testa
Ugo
U
Hogg
James C
JC
D000328:Adult; D018952:Antigens, CD34 / Q000032:analysis; D001772:Blood Cell Count; D001773:Blood Cells / Q000166:cytology* / Q000276:immunology; D016179:Granulocyte Colony-Stimulating Factor / Q000097:blood; D006412:Hematopoietic Stem Cells / Q000166:cytology* / Q000276:immunology; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D015850:Interleukin-6 / Q000097:blood; D008297:Male; D008565:Membrane Proteins / Q000097:blood; D008875:Middle Aged; D010806:Physical Education and Training; D010807:Physical Endurance / Q000502:physiology; D012016:Reference Values; D012420:Running / Q000502:physiology*; D013997:Time Factors
D018952:Antigens, CD34; D015850:Interleukin-6; D008565:Membrane Proteins; C084881:flt3 ligand protein; D016179:Granulocyte Colony-Stimulating Factor; D006854:Hydrocortisone