Effects of Exhaustive Exercise on Inflammatory, Apoptotic, and Antioxidative Signaling Pathways in Human Peripheral...

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.