Background: In this trial, we analyzed the plasma levels of novel biomarkers that reflect different pathophysiological pathways (sST2: mechanical strain, IGF-BP2: metabolic pathways, suPAR and GDF-15: inflammatory processes) in patients undergoing physical exercise to investigate the effects of training on their plasma concentrations.
Methods: Plasma concentrations of novel biomarkers (sST2, IGF-BP2, suPAR and GDF-15) were analyzed by means of ELISA in patients with stable coronary artery disease (CAD) undergoing four weeks of high- and moderate-intensity training (EXCITE Trial) and in patients with one or more cardiovascular risk factors undergoing eight months of intensive physical exercise (IGF-BP2). Plasma levels of sST2 in patients undergoing eight months of intensive exercise have been published previously by our study group (1.13-fold change, P=0.045).
Results: Four weeks of high-intensity exercise training resulted in a statistically significant change in the plasma level of sST2 (1.106-fold change, P=0.0054) and IGF-BP2 (1.24-fold-change, P=0.0165). Eight months of intensive exercise resulted in a significant increase of IGF-BP2 (median 61.2 ng/mL to 80.7 ng/mL, 1.319-fold change, P=0.006).
Conclusions: The significant increase of sST2 after four weeks might be a short-term effect due to the mechanical strain caused by the high-intensity training program, whereas the increase in IGF-BP2 after four weeks and eight months is likely a result of metabolic changes due to physical exercise.