Exercise-induced increases in NT-proBNP are not related to the exercise-induced immune response.
OBJECTIVE
To investigate if the exercise-induced immune response contributes to the exercise-induced increase in brain natriuretic peptide (BNP) in healthy athletes. This has previously been speculated, as elevated concentrations of BNP or N-terminal pro brain natriuretic peptide (NT-proBNP) in cardiovascular patients were found to be related to immune reactions and elevations in inflammatory cytokines such as interleukin 6 (IL-6).


METHODS
Stored serum samples were analysed for NT-proBNP concentrations of 14 healthy endurance athletes (mean age: 25 (SD 5) years; VO(2peak) 67 (SD 6) ml/min/kg), who had been examined previously for exercise-induced immune reactions and their dependence on carbohydrate supplementation (6 or 12% carbohydrate vs placebo beverages) after three bouts of 4 h cycling at a given workload of 70% of the individual anaerobic threshold. Venous blood samples were taken before, immediately after, and 1 h and 1 day after exercise. Leucocyte subpopulations were determined immediately after blood sampling by flow cytometry. Serum samples for posterior analysis of C-reactive protein (CRP), IL-6, cortisol and NT-proBNP were stored at -80 degrees C.


RESULTS
The exercise-induced increases in NT-proBNP (p<0.001) were not related to the exercise-induced immune response, although exercise induced marked (CHOS-dependent) increases in IL-6, CRP, cortisol, leucocytes, neutrophils, monocytes and natural killer cells.


CONCLUSIONS
It is unlikely that the exercise-induced increases in NT-proBNP or BNP in healthy athletes are caused by the exercise-induced immune response. Therefore, exercise-induced increases in NT-proBNP or BNP in healthy athletes have to be differentiated from increases in cardiovascular patients with systemic inflammation.
Scharhag
J
J
Institute of Sports and Preventive Medicine, Campus, Building B 8.2, University of Saarland, 66123 Saarbrücken, Germany. j.scharhag@mx.uni-saarland.de
Meyer
T
T
Auracher
M
M
Müller
M
M
Herrmann
M
M
Gabriel
H
H
Herrmann
W
W
Kindermann
W
W
D000328:Adult; D004797:Enzyme-Linked Immunosorbent Assay; D015444:Exercise / Q000502:physiology*; D005434:Flow Cytometry; D006801:Humans; D007962:Leukocytes / Q000276:immunology*; D020097:Natriuretic Peptide, Brain / Q000378:metabolism*; D010446:Peptide Fragments / Q000378:metabolism; D010807:Physical Endurance / Q000502:physiology*; D013177:Sports / Q000502:physiology*
D010446:Peptide Fragments; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain