Article

Background Acute vascular effects of high intensity physical activity are
incompletely characterized. Circulating microparticles are cellular markers for
vascular activation and damage. Methods Microparticles were analysed in 99
marathon runners (49 +/- 6 years, 22% female) of the prospective Berlin Beat of
Running study. Blood samples were taken within three days before, immediately
after and within two days after the marathon run. Endothelial-derived
microparticles were labelled with CD144, CD31 and CD62E, platelet-derived
microparticles with CD62P and CD42b, leukocyte-derived microparticles with CD45
and monocyte-derived microparticles with CD14. Results Marathon running induced
leukocytosis (5.9 +/- 0.1 to 14.8 +/- 0.3 10(9)/l, p < 0.0001) and increased
platelet counts (239 +/- 4.6 to 281 +/- 5.9 10(9)/l, p < 0.0001) immediately
after the marathon. Blood monocytes increased and lymphocytes decreased after the
run ( p < 0.0001). Endothelial-derived microparticles were acutely increased ( p
= 0.008) due to a 23% increase of apoptotic endothelial-derived microparticles (
p = 0.007) and returned to baseline within two days after the marathon.
Thrombocyte-derived microparticles acutely increased by 38% accompanied by an
increase in activated and apoptotic thrombocyte-derived microparticles ( p </=
0.0001) each. Both monocyte- and leukocyte-derived microparticles were decreased
immediately after marathon run
( p < 0.0001) and remained below baseline until
day 2. Troponin T increased from 12 to 32 ng/l ( p < 0.0001) immediately after
the run and returned to baseline after two days. Conclusion Circulating apoptotic
endothelial- and thrombocyte-derived microparticles increased after marathon
running consistent with an acute pro-thrombotic and pro-inflammatory state.
Exercise-induced vascular damage reflected by microparticles could indicate
potential mechanisms of post-exertional cardiovascular complications. Further
studies are warranted to investigate microparticles as markers to identify
individuals prone to such complications.

Langue : ANGLAIS