Medizinische Universität Graz - Research portal
Selected Publication:
Kröpfl, J.
Einfluss von körperlicher Belastung auf zirkulierende humane hämatopoetische Stamm- und Progenitorzellen
[ Dissertation ] Medical University of Graz; 2013. pp. 77
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- Authors Med Uni Graz:
- Kröpfl Julia
- Advisor:
- Dohr Gottfried
- Holasek Sandra Johanna
- Müller Wolfram
- Stelzer Ingeborg
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- Abstract:
- Objective: Adult human hematopoietic stem and progenitor cells (HSPCs) mobilized from the bone marrow into the peripheral blood show great potential for regeneration over the whole lifetime of a human. This thesis deals with the influence of physical exercise at both normoxia and normobaric hypoxia on the number and functionality of adult circulating hematopoietic progenitor cells (CPCs) which represent the part of HSPCs defined as CD34+/CD45dim side scatter low in the adult human blood circulation system. Two studies were designed to investigate CPC kinetics and functionality in the peripheral blood after defined exercise test protocols as well as the involvement of different exercise-induced blood parameters as possibly influencing agents. Methods: In study design I, ten healthy male subjects (25.3 ± 4.4 yrs) underwent a standardized cycle incremental exercise test protocol (40 W + 20 W/min) under either normoxic (FiO2 ~ 0.21) or hypoxic conditions (FiO2 < 0.15, equals 3,500 m, 3 h exposure). Blood was drawn from the cubital vein before and 10, 30, 60 and 120 min after exercise. Study design II involved the testing of seven patients (63.4 ± 7.0 yrs) undergoing cardiac rehabilitation. All subjects performed 2-3 different exercise tests (randomly chosen out of four) on a cycle ergometer; each exercise test was expected to trigger a different blood lactate concentration. Venous blood was drawn from the cubital vein before and immediately after each intervention. Results: Data of study I showed a significant increase of CPC release under normoxic as well as hypoxic conditions after 10 min of recovery. Most interestingly, although CD34+/CD45dim cells increased in number, the proliferative capacity/functionality of CPCs decreased significantly 10 min after cessation of exercise. Blood parameters of oxidative stress and cortisol levels significantly correlated with CPC count. The pro-inflammatory cytokine interleukin-6 as well as norepinephrine showed a significant increase after cessation of exercise. Hypoxia corresponding to 3,500 m altitude did not provoke an additional effect. In addition, exercise-induced norepinephrine concentrations seen in vivo also had a significant effect on CPC functionality tested in vitro. Study design II revealed a significant relationship between maximum exercise-induced blood lactate concentration and CPC count, independent of the exercise mode. Conclusion: Physical exercise stress influences CPCs in a complex way; therefore effects of physical exercise on regeneration and repair processes are to be expected.