Effects of Exhaustive Exercise on Inflammatory, Apoptotic, and Antioxidative Signaling Pathways in Human Peripheral Blood Mononuclear Cells

In the present study, we investigated the effects of exhaustive exercise and recovery on inflammatory, pro-apoptotic, and anti-oxidative responses in human peripheral blood mononuclear cells (PBMCs). Sixteen volunteers participated in a guided physical activity program in which they were subjected to progressive exercise on the treadmill until they were exhausted followed by an 1-hour recovery period. Isolated human PBMCs were collected before exercise, immediately after exercise, and after 1-hour recovery. Exhaustive exercise induced expression of heme oxygenase-1 and glutamate cysteine ligase catalytic subunit and activation of NF-κB and NF-E2 related factor 2 (Nrf2). Apoptosis, as measured by activity and cleavage of caspase-3 and its substrate PARP also significantly increased. However, induction of redox signaling and the pro-apoptotic response fully returned to the baseline level during the 1-hour recovery period. On the other hand, COX-2 expression was continuously elevated after exercise cessation throughout the 1-hour recovery period. Taking all these findings into account, we conclude that exhaustive exercise transiently induces Nrf2-mediated antioxidant gene expression and eliminates damaged cells through apoptosis as part of an adaptive cytoprotective response against oxidative and inflammatory stress.