Description:
<jats:sec><jats:title>Background</jats:title><jats:p> Acute vascular effects of high intensity physical activity are incompletely characterized. Circulating microparticles are cellular markers for vascular activation and damage. </jats:p></jats:sec><jats:sec><jats:title>Methods</jats:title><jats:p> 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. </jats:p></jats:sec><jats:sec><jats:title>Results</jats:title><jats:p> Marathon running induced leukocytosis (5.9 ± 0.1 to 14.8 ± 0.3 10<jats:sup>9</jats:sup>/l, p < 0.0001) and increased platelet counts (239 ± 4.6 to 281 ± 5.9 10<jats:sup>9</jats:sup>/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. </jats:p></jats:sec><jats:sec><jats:title>Conclusion</jats:title><jats:p> 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. </jats:p></jats:sec>