Laboratoire Croissance cellulaire, Réparation et Régénération Tissulaires, UMR CNRS 7149, Faculté des Sciences et Techniques, Université Paris Est, Créteil, France.
Exp Gerontol. 2009 Mar;44(3):177-82. doi: 10.1016/j.exger.2008.10.003. Epub 2008 Oct 17.
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.
缺血性心脏病的发病率随着年龄的增长而增加,老年人更容易发生心肌梗死。耐力运动(如跑步机训练)可提供对成人心脏缺血再灌注(IR)事件的心脏保护作用,但定期运动的这种潜在有益作用在衰老过程中从未得到过评估。因此,本研究旨在探讨适度跑步训练对衰老心肌缺血后收缩功能和冠状动脉灌注的影响。久坐不动的(24 月龄-久坐不动;n=10)和训练有素的衰老(24 月龄-训练;n=11;适度跑步:每天 1 小时,每周 5 天,持续 12 周)大鼠的离体心脏接受 45 分钟低流量缺血(初始冠状动脉流量的 15%(CF)),随后进行 30 分钟再灌注。在再灌注 1、3、5、10、15、20、25 和 30 分钟时记录主动张力(AT)和 CF。通过 Oxyblotting 和 Western blotting 分别测定左心室蛋白羰基化以及热休克蛋白 70(HSP70)和内皮型一氧化氮合酶(eNOS)的含量。有规律的体育锻炼可改善衰老心脏再灌注期间功能后缺血性恢复(AT 和 CF)的损伤,这种心脏保护作用与有限的蛋白氧化和增加的 HSP70 和 eNOS 心肌含量有关。