title: Exercise-induced norepinephrine decreases circulating hematopoietic stem and progenitor cell colony-forming capacity.
abstract: A recent study showed that ergometry increased circulating hematopoietic stem and progenitor cell (CPC) numbers, but reduced hematopoietic colony forming capacity/functionality under normoxia and normobaric hypoxia. Herein we investigated whether an exercise-induced elevated plasma free/bound norepinephrine (NE) concentration could be responsible for directly influencing CPC functionality. Venous blood was taken from ten healthy male subjects (25.3+/-4.4 yrs) before and 4 times after ergometry under normoxia and normobaric hypoxia (FiO2<0.15). The circulating hematopoietic stem and progenitor cell numbers were correlated with free/bound NE, free/bound epinephrine (EPI), cortisol (Co) and interleukin-6 (IL-6). Additionally, the influence of exercise-induced NE and blood lactate (La) on CPC functionality was analyzed in a randomly selected group of subjects (n = 6) in vitro under normoxia by secondary colony-forming unit granulocyte macrophage assays. Concentrations of free NE, EPI, Co and IL-6 were significantly increased post-exercise under normoxia/hypoxia. Ergometry-induced free NE concentrations found in vivo showed a significant impairment of CPC functionality in vitro under normoxia. Thus, ergometry-induced free NE was thought to trigger CPC mobilization 10 minutes post-exercise, but as previously shown impairs CPC proliferative capacity/functionality at the same time. The obtained results suggest that an ergometry-induced free NE concentration has a direct negative effect on CPC functionality. Cortisol may further influence CPC dynamics and functionality.
authors.affiliation: Institute of Human Movement Sciences and Sport, Exercise Physiology Lab, ETH Zurich, Zurich, Switzerland; Institute of Biophysics, Medical University of Graz, Graz, Austria.
authors.forename: Julia M
authors.initials: JM
authors.lastname: Kröpfl
authors.affiliation: Clinical Institute of Medical and Chemical Laboratory Diagnostics, Research Unit on Lifestyle and Inflammation-associated Risk Biomarkers, Medical University of Graz, Graz, Austria; Institute for Pathophysiology and Immunology, Medical University of Graz, Graz, Austria.
authors.forename: Ingeborg
authors.initials: I
authors.lastname: Stelzer
authors.affiliation: Clinical Institute of Medical and Chemical Laboratory Diagnostics, Research Unit on Lifestyle and Inflammation-associated Risk Biomarkers, Medical University of Graz, Graz, Austria; BioTechMed-Graz, Karl-Franzens University & Technical University & Medical University of Graz, Graz, Austria.
authors.forename: Harald
authors.initials: H
authors.lastname: Mangge
authors.affiliation: Department of Ophthalmology, Medical University of Graz, Graz, Austria.
authors.forename: Karin
authors.initials: K
authors.lastname: Pekovits
authors.affiliation: Institute for Pathophysiology and Immunology, Medical University of Graz, Graz, Austria.
authors.forename: Robert
authors.initials: R
authors.lastname: Fuchs
authors.affiliation: Institute for Pathophysiology and Immunology, Medical University of Graz, Graz, Austria.
authors.forename: Nathalie
authors.initials: N
authors.lastname: Allard
authors.affiliation: Clinical Institute of Medical and Chemical Laboratory Diagnostics, Research Unit on Lifestyle and Inflammation-associated Risk Biomarkers, Medical University of Graz, Graz, Austria; Institute for Pathophysiology and Immunology, Medical University of Graz, Graz, Austria.
authors.forename: Lukas
authors.initials: L
authors.lastname: Schinagl
authors.affiliation: Institute of Sports Science, Karl-Franzens University of Graz, Graz, Austria.
authors.forename: Peter
authors.initials: P
authors.lastname: Hofmann
authors.affiliation: Institute of Cell Biology, Histology and Embryology, Medical University of Graz, Graz, Austria.
authors.forename: Gottfried
authors.initials: G
authors.lastname: Dohr
authors.affiliation: Institute for Pathophysiology and Immunology, Medical University of Graz, Graz, Austria.
authors.forename: Sandra
authors.initials: S
authors.lastname: Wallner-Liebmann
authors.affiliation: Department of Pulmonology, Medical University of Graz, Graz, Austria.
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Domej
authors.affiliation: Institute of Biophysics, Medical University of Graz, Graz, Austria.
authors.forename: Wolfram
authors.initials: W
authors.lastname: Müller
mesh_terms: D000328:Adult; D018952:Antigens, CD34 / Q000378:metabolism; D001772:Blood Cell Count; D015687:Cell Hypoxia; D049109:Cell Proliferation; D003114:Colony-Forming Units Assay; D004837:Epinephrine / Q000097:blood; D016552:Ergometry; D015444:Exercise; D006412:Hematopoietic Stem Cells / Q000166:cytology*; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D015850:Interleukin-6 / Q000097:blood; D007773:Lactates / Q000097:blood; D017493:Leukocyte Common Antigens / Q000378:metabolism; D008297:Male; D009638:Norepinephrine / Q000097:blood*
chemical_list: D018952:Antigens, CD34; D015850:Interleukin-6; D007773:Lactates; D017493:Leukocyte Common Antigens; D006854:Hydrocortisone; D009638:Norepinephrine; D004837:Epinephrine