Exercise training improves functional post-ischemic recovery in senescent heart.
The incidence of ischemic cardiac diseases increases with age and elderly subjects are more vulnerable to myocardial infarction. Endurance exercise (e.g. treadmill training) provides cardioprotection against an ischemia and reperfusion (IR) event in adult heart but such a potential beneficial effect of regular exercise has never been evaluated during aging. Therefore, this study investigated the effects of moderate running training on post-ischemic recovery of contractile function and coronary perfusion in senescent myocardium. Isolated hearts of sedentary (24 mo-sedentary; n=10) and trained senescent (24 mo-trained; n=11; moderate running: 1h/day, 5 days/week for 12 weeks) rats were submitted to 45min low-flow ischemia (15% of initial coronary flow (CF)) followed by 30min reperfusion. Active tension (AT) and CF were recorded at baseline and after 1, 3, 5, 10, 15, 20, 25 and 30min of reperfusion. Left ventricular protein carbonylation, and both heat-shock-protein 70 (HSP70) and endothelial nitric oxide synthase (eNOS) contents were determined by Oxyblotting and Western blotting, respectively. Regular physical exercise improves impairment of functional post-ischemic recovery (AT and CF) of aged hearts during reperfusion and this cardioprotection is associated to limited protein oxidation and increased HSP70 and eNOS myocardial contents.
Le Page
Christine
C
Laboratoire Croissance cellulaire, Réparation et Régénération Tissulaires, UMR CNRS 7149, Faculté des Sciences et Techniques, Université Paris Est, Créteil, France. Christine.Le-Page@univ-paris5.fr
Noirez
Philippe
P
Courty
José
J
Riou
Bruno
B
Swynghedauw
Bernard
B
Besse
Sophie
S
D000328:Adult; D000368:Aged; D000375:Aging / Q000502:physiology*; D000704:Analysis of Variance; D000818:Animals; D015153:Blotting, Western; D002950:Citrate (si)-Synthase / Q000378:metabolism; D003326:Coronary Circulation / Q000502:physiology; D015444:Exercise; D018840:HSP70 Heat-Shock Proteins / Q000378:metabolism; D006801:Humans; D008297:Male; D018482:Muscle, Skeletal / Q000378:metabolism; D009200:Myocardial Contraction / Q000502:physiology; D017202:Myocardial Ischemia / Q000378:metabolism* / Q000503:physiopathology; D015428:Myocardial Reperfusion Injury / Q000378:metabolism / Q000517:prevention & control*; D009206:Myocardium / Q000378:metabolism; D052250:Nitric Oxide Synthase Type III / Q000378:metabolism; D018384:Oxidative Stress; D010477:Perfusion; D010805:Physical Conditioning, Animal / Q000502:physiology*; D050050:Protein Carbonylation; D051381:Rats; D017208:Rats, Wistar
D018840:HSP70 Heat-Shock Proteins; D052250:Nitric Oxide Synthase Type III; D002950:Citrate (si)-Synthase