Microparticles (MP) are shed extracellular vesicles that express the prothrombotic tissue factor (TF). Aerobic exercise may reduce MP count and TF expression. This study investigated the impact of acute running or rest followed by standardized meal consumption on MP phenotypes and TF expression.
Fifteen males (age, 22.9 ± 3.3 yr; body mass, 81.9 ± 11.4 kg; V˙O2max, 54.9 ± 6.5 mL·kg−1·min−1; mean ± SD) completed 1 h of running (70% V˙O2max) or rest at 9:00 AM and consumed a standardized meal (1170 kcal, 43% CHO, 17% PRO, 40% fat) at 10:45 AM. Venous blood samples were taken at 9:00 AM, 10:00 AM, and 11:30 AM. The MP concentration, diameter, phenotypes, and TF expression were assessed using nanoparticle tracking analysis and flow cytometry.
Nanoparticle tracking analysis identified no changes in MP concentration or diameter in response to time or trial. Flow cytometry revealed total MP count increased from 9:00 AM to 10:00 AM (1.62 ± 2.28 to 1.74 ± 2.61 × 1010 L−1, P = 0.016, effect size (η2) = 0.105), but was unaffected by trial. TF+ platelet-derived MP % reduced from 9:00 AM to 10:00 AM (44.0% ± 21.2% to 21.5% ± 9.3%, P = 0.001, η2 = 0.582) after exercise only (control, 36.8% ± 18.2% to 34.9% ± 11.9%; P = 0.972). TF+ neutrophil-derived MP percentage reduced from 9:00 AM to 11:30 AM (42.3% ± 17.2% to 25.1% ± 14.9%; P = 0.048, η2 = 0.801) in the exercise trial only (control, 28.5% ± 15.7% to 32.2% ± 9.6%; P = 0.508).
Running induced a significant reduction in %TF+ platelet and neutrophil MP, suggesting a transient reduction in cardiovascular risk via reduced TF-stimulated thrombosis. This requires further investigation over longer periods in cardiovascular disease populations.
1School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, UNITED KINGDOM
2Department of Infection, Immunity and Inflammation, University of Leicester, Leicester, UNITED KINGDOM
3Leicester School of Allied Health Sciences, Faculty of Health and Life Sciences, De Montfort University, Leicester, UNITED KINGDOM
4University Hospitals of Leicester NHS Trust, Infirmary Square, Leicester, UNITED KINGDOM
Address for correspondence: Nicolette C Bishop, Ph.D., School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough LE11 3TU, United Kingdom; E-mail: N.C.Bishop@lboro.ac.uk.
Submitted for publication November 2018.
Accepted for publication March 2019.
Online date: March 26, 2019