Summary
Physical activity is associated with cardiovascular risk reduction, but the effects
of exercise on platelet activation remain controversial. We investigated the effects
of regular high-amount, high intensity aerobic exercise on in vivo thromboxane (TX)-dependent platelet activation and plasma levels of platelet-derived
proteins, CD40L and P-selectin, and whether platelet variables changes may be related
to changes in high-density lipoprotein (HDL) and in the extent of oxidative stress
and oxidative stress-related inflammation, as reflected by urinary isoprostane excretion
and endogenous soluble receptor for advanced glycation end-products (esRAGE), respectively.
Urinary excretion of 11-dehydro-TXB2 and 8-iso-prostaglandin (PG)F2α and plasma levels of P-selectin, CD40L and esRAGE were measured before and after
a eight-week standardised aerobic high-amount–high-intensity training program in 22
sedentary subjects with low-to-intermediate risk. Exercise training had a clear beneficial
effect on HDL cholesterol (+10%, p=0.027) and triglyceride (-27%, p=0.008) concentration.
In addition, a significant (p<0.0001) decrease in urinary 11-dehydro-TXB2 (26%), 8-iso-PGF2α (21 %), plasma P-selectin (27%), CD40L (35%) and a 61% increase in esRAGE were observed.
Multiple regression analysis revealed that urinary 8-iso-PGF2α [beta=0.33, SEM=0.116, p=0.027] and esRAGE (beta=-0.30, SEM=31.3, p=0.046) were the
only significant predictors of urinary 11-dehydro-TXB2 excretion rate over the training period. In conclusion, regular high-amount–high-intensity
exercise training has broad beneficial effects on platelet activation markers, paralleled
and possibly associated with changes in the lipoprotein profile and in markers of
lipid peroxidation and AGE/RAGE axis. Our findings may help explaining why a similar
amount of exercise exerts significant benefits in preventing cardiovascular events.
Keywords
Aerobic exercise - platelet activation - oxidative stress - esRAGE