N-acetyl-L-cysteine inhibits exercise-induced lymphocyte apoptotic protein alterations.
OBJECTIVE
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 degrees 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 (24 h) 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 24 h postgroups (EX + SAL + 24 h and EX + NAC + 24 h).


CONCLUSIONS
These results suggest that oxidative stress acting through a mitochondrial pathway may play a role in intestinal lymphocyte apoptosis after strenuous exercise.
Quadrilatero
Joe
J
Department of Health Studies and Gerontology, Faculty of Applied Health Sciences, University of Waterloo, Waterloo, Ontario, Canada N2L 3G1.
Hoffman-Goetz
Laurie
L
D000111:Acetylcysteine / Q000494:pharmacology*; D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D015153:Blotting, Western; D053148:Caspase 3; D020169:Caspases / Q000378:metabolism; D045304:Cytochromes c / Q000378:metabolism; D005080:Exercise Test; D005260:Female; D008214:Lymphocytes / Q000187:drug effects* / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism; D011897:Random Allocation
D019253:Proto-Oncogene Proteins c-bcl-2; D045304:Cytochromes c; C505409:Casp3 protein, mouse; D053148:Caspase 3; D020169:Caspases; D000111:Acetylcysteine