Exercise in the prevention of cardiovascular diseases Acute and chronic effects of exercise on the circulating levels of endothelial progenitor cells and vascular regeneration potential

Abstract

Endothelial progenitor cells (EPCs) play a pivotal role in vascular repair and angiogenesis, whereas circulating endothelial cells (CECs) serve as indicators of endothelial damage. The imbalance between the levels of EPCs and CECs represents the vascular regeneration potential, often compromised in individuals with cardiovascular risk factors (CVRFs) and cardiovascular diseases (CVDs). Limited data exist on the impact of exercise on the balance between EPCs and CECs in these populations. This thesis aims to evaluate the acute and chronic effects of exercise on the circulating levels of EPCs and CECs in individuals with CVRFs and CVDs. Specifically, the objectives are: 1) Investigate the impact of two exercise sessions with different durations (30 minutes versus 45 minutes) on circulating levels of EPCs and CECs in individuals with CVRFs; 2) Examine the effects of maximal exercise on the circulating levels of EPCs and CECs in patients with heart failure (HF); and 3) Evaluate the effects of 18 weeks of multicomponent exercise training on circulating levels of EPCs and CECs in individuals with CVRFs. Blood samples were collected to quantify EPCs and CECs using flow cytometry. The main findings revealed an increase of 1.8 ±1.7% in the levels of EPCs and a decrease in the CEC count after the 30-minute exercise session in participants with CVRFs. No significant changes in EPCs and CECs were observed after the 45-minute exercise session. In patients with HF, the levels of EPCs increased with no significant change in CECs after maximal exercise. A supervised exercise training program comprising 36 exercise sessions, held twice weekly (each session lasting 60 minutes), and consisting of multicomponent exercises (i.e., a combination of aerobic, muscle strengthening, flexibility, and balance exercises) resulted in increased levels of EPCs and no change in CECs levels. In conclusion, both single exercise sessions and multicomponent exercise training demonstrated the capacity to increase the circulating levels of EPCs without a concurrent increase in endothelial damage, as indicated by the CECs count. Therefore, exercise stands as a useful tool to prevent CVDs by enhancing vascular repair potential.