Hung Ching-Hsia, Chen Yu-Wen, Shao Dong-Zi, Chang Che-Ning, Tsai Yung-Yuh, Cheng Juei-Tang
Department of Physical Therapy, National Cheng Kung University, Tainan, Taiwan.
Appl Physiol Nutr Metab. 2008 Oct;33(5):976-83. doi: 10.1139/H08-081.
Higher expression of heat shock protein 72 (HSP72) reduces the mortality rate and organ damage in septic shock and prevents cardiac mitochondrial dysfunction due to lipopolysaccharide (LPS). Our hypothesis is that exercise preconditioning may increase the expression of HSP72 in heart and the nucleus tractus solitarii (NTS) of the brain to alleviate the cardiovascular dysfunction in type I diabetic rats receiving endotoxin. Wistar rats were randomly assigned to the following groups: sedentary normal, sedentary type I diabetic rats, and type I diabetic rats with exercise training. The trained rats ran on a treadmill 5 d.week-1, 30-60 min.d-1, at an intensity of 1.0 mile.h-1 (1 mile = 1.6 km) over a 3 week period. Twenty-four hours after the last training session, we compared the temporal profiles of mean arterial pressure, heart rate, cardiac output, stroke volume, and serum tumor necrosis factor alpha level in rats receiving an injection of LPS. In addition, HSP72 expression in heart and NTS from each group was determined. We found that HSP72 expression in the heart and NTS was significantly increased in diabetic rats with exercise training. After administration of LPS, the survival time was significantly longer in diabetic rats with exercise training. Additionaly, serum tumor necrosis factor alpha levels decreased as compared with those rats not receiving exercise training. Exercise training also diminished cardiovascular dysfunction in diabetic rats during endotoxemia. These data suggest that exercise may increase the expression of HSP72 in the heart and NTS to protect against the high mortality rate and attenuate cardiovascular dysfunction in diabetic rats during endotoxemia.
热休克蛋白72（HSP72）的高表达可降低脓毒性休克的死亡率和器官损伤，并预防脂多糖（LPS）所致的心脏线粒体功能障碍。我们的假设是，运动预处理可能会增加心脏和脑孤束核（NTS）中HSP72的表达，以减轻接受内毒素的I型糖尿病大鼠的心血管功能障碍。将Wistar大鼠随机分为以下几组：久坐不动的正常大鼠、久坐不动的I型糖尿病大鼠以及接受运动训练的I型糖尿病大鼠。训练大鼠在跑步机上每周跑5天，每天30 - 60分钟，强度为1.0英里/小时（1英里 = 1.6公里），持续3周。在最后一次训练 session 后24小时，我们比较了注射LPS的大鼠的平均动脉压、心率、心输出量、每搏输出量和血清肿瘤坏死因子α水平的时间变化情况。此外，还测定了每组大鼠心脏和NTS中HSP72的表达。我们发现，接受运动训练的糖尿病大鼠心脏和NTS中HSP72的表达显著增加。给予LPS后，接受运动训练的糖尿病大鼠的存活时间显著延长。此外，与未接受运动训练的大鼠相比，血清肿瘤坏死因子α水平降低。运动训练还减轻了内毒素血症期间糖尿病大鼠的心血管功能障碍。这些数据表明，运动可能会增加心脏和NTS中HSP72的表达，以预防高死亡率，并减轻内毒素血症期间糖尿病大鼠的心血管功能障碍。
