长期递增负荷运动对大鼠胸腺细胞凋亡及caspaes-3表达的影响

Effect of Long-term Progressive Loading Treadmill Exercise on Thymus Cell Apoptosis and Caspaes-3 Expression in Rats

目的:通过研究6周递增负荷运动过程中大鼠胸腺细胞凋亡的情况及凋亡执行因子caspaes-3的表达情况,探讨长期递增负荷运动对胸腺的影响。方法:96只SD大鼠随机分为运动组和对照组,运动组进行6周递增负荷跑台训练,6次/周,30 min/d,分别于第0、2、4和6周末利用TUNEL法和免疫组化技术测定运动前安静状态和运动后即刻组大鼠胸腺细胞的凋亡情况和caspaes-3的表达水平。结果:6周递增负荷运动过程中,胸腺指数呈进行性减小,与WK0A组相比,WK2A组显著减小(P<0.05),WK4和WK6A组也显著减小(P<0.01),与WK2A组相比,WK4和WK6A组显著减小(P<0.01)。胸腺细胞凋亡指数(apoptosis index,AI)适应性变化是呈进行性增加。与WK0A组相比,WK2、WK4和WK6A组显著增加(P<0.01),与WK2A组相比,WK4和WK6A组显著增加(P<0.01),与WK4A组相比,WK6A组显著增加(P<0.01)。AI应答性变化为,WK2J组与WK2A组相比,AI显著增加(P<0.05),WK6J组与WK6A组相比,AI显著增加(P<0.05)。胸腺组织Caspase-3蛋白表达的适应性变化也是呈进行性增加。与WK0A组相比,WK4和WK6A组显著增加(P<0.01),Caspase-3的应答性变化为,WK4J组与WK4A组相比,AI显著增加(P<0.05),WK6J组与WK6A组相比,AI显著增加(P<0.05)。结论:随着递增负荷的进程,胸腺指数明显减小,胸腺细胞凋亡越来越多;同时Caspase-3表达也越来越多,表明长期递增负荷运动过程中,胸腺功能下降可能是胸腺细胞凋亡增加引起的,而胸腺细胞凋亡增加可能是由Caspase-3等凋亡因子介导的。

Purpose： This study aims at exploring the effect of long-term progressive loading treadmill exercise on thymus by measuring the thymus cell apoptosis and easpaes - 3 expression in rats during exercise. Methods ： Nine- ty-six SD rats were randomly divided into control group and exercise group. Exercise group rats participated in six weeks treadmill training, 30 minutes per day. The thymus cell apoptosis and caspaes -3 expression were meas- ured at 0 week, after 2 weeks exercise, 4 weeks exercise and 6 weeks exercise by TUNEL and immunohistochem- isty. Results ： 1 ） The thymus cell apoptosis was decreased during the whole exercise program. It was lower after 2 weeks, 4 weeks and 6 weeks exercise than at 0 week （ before exercise） （P 〈 0.05 ）, and it was higher after 4 weeks exercise and 6 weeks exercise than after 2 weeks exercise （ P 〈 0.01 ）. 2 ） Apoptosis index （AI） was in- creased after exercise. It increased after 2 weeks, 4weeks and 6 weeks exercise than at 0 week （P 〈 0.01 ）, it was higher after 4 weeks exercise and 6 weeks exercise than after 2 weeks exercise （ P 〈0.01 ） , and it was highest after 6 weeks exercise （P 〈 0.01 ）. Compared with parallel control group, AI in 2 weeks exercise group and 6 weeks exercise group was increased respectively （P 〈 0.05）. 3） The protein expression of caspase - 3 was in- creased after exercise. It was increased after 4 weeks exercise and 6 weeks exercise. Compared with parallel con- trol group, it was increased in 4 weeks exercise group and 6 weeks exercise group respectively （ P 〈 0.05 ）. Con-clusion： During the whole exercise progression, AI decreased significantly, thymus cell apoptosis and the protein expression of caspase - 3 increased, which suggested that exercise-induced immunosuppression may be induced by increasing cell apoptosis that via caspase -3.