Effects of normoxic and hypoxic exercise training on the bactericidal capacity and subsequent apoptosis of neutrophils in sedentary men

This study investigates how exercise training with or without hypoxic exposure affects the bactericidal activity and subsequent apoptosis of neutrophils following strenuous exercise. A total of 60 healthy, sedentary men were randomly divided into four groups (n = 15 in each group), who were exposed to 21% O2 [normoxic control (NC)] or 15% O2 [hypoxic control (HC)] at rest or were trained at 50% of peak work rate at 21% O2 [normoxic training (NT)] or 15% O2 [hypoxic training (HT)] for 30  min/day, 5 days/week for 4 weeks. Before the intervention, acute strenuous exercise (SE) enhanced the phagocytosis ofEscherichia coli (E. coli) by neutrophils and the release of neutrophil oxidant products in response toE. coli, accompanied by increases in the expression of adhesion molecules (CD62L, CD11b, and CD11a), an opsonic receptor (Fc γIIIBR), and complement receptors (C1qRp and CD5aR) on neutrophils. Subsequently, the SE facilitated caspase-3 activation and phosphatidylserine exposure inE. coli-stimulated neutrophils. Furthermore, 4 weeks of HT promoted the expressions of adhesion molecules and opsonic/complement receptors on neutrophils, and it also augmented the bactericidal and apoptotic activities of neutrophils at rest or after SE. However, NT, HC, and NC did not influence these neutrophil-related immune responses to strenuous exercise. Therefore, we conclude that the HT regimen effectively promotes the bactericidal capacity of neutrophils, and facilitates their subseque...
Source: European Journal of Applied Physiology - Category: Physiology Source Type: research