To investigate the effect of strenuous exercise and antioxidant administration on pro- and antiapoptotic protein expression in intestinal lymphocytes.Methods:
Female C57BL/6 mice (N = 52) were randomly assigned to receive N-acetyl-L-cysteine (NAC; 1 g·kg−1) or saline (SAL) 30 min before treadmill exercise (EX) for 90 min and 2° slope (30 min at 22 m·min−1, 30 min at 25 m·min−1, and 30 min at 28 m·min−1) and sacrificed immediately (Imm) or 24 h (24h) after exercise. Control mice were exposed to treadmill noise and vibration without running (nonexercised). Intestinal lymphocytes (IL) were isolated and pro- and antiapoptotic protein expression was evaluated by Western blot analysis.Results:
IL protein levels of proapoptotic (caspase 3 and cytosolic cytochrome c) and antiapoptotic (Bcl-2) were significantly different among groups. Relative to nonexercised mice, protein levels of caspase 3 (P < 0.001) and cytosolic cytochrome c (P < 0.005) were significantly elevated, whereas Bcl-2 (P < 0.05) was significantly lower immediately after exercise in mice receiving saline (EX+SAL+Imm) but not in animals receiving NAC (EX+NAC+Imm) or both 24h postgroups (EX+SAL+24h and EX+NAC+24h).Conclusion:
These results suggest that oxidative stress acting through a mitochondrial pathway may play a role in intestinal lymphocyte apoptosis after strenuous exercise.