摘要
背景:急性心肌缺血缺氧可以引起血管紧张素Ⅱ的表达升高,上调心肌细胞Toll样受体4和核因子κB的蛋白表达。Toll样受体4缺乏的小鼠在压力超负荷的情况下心肌肥大程度下降,提示Toll样受体4/核因子κBp65参与了应激和心肌肥大发生、发展过程。目的:通过建立一次急性运动、4周和10周递增负荷运动模型,探讨Toll样受体4/核因子κBp65信号通路在心肌适应性运动过程中的作用。方法:大鼠随机分为3个大组,分别进行一次急性运动、4周耐力训练和10周耐力训练。采用跑台运动方式训练。每个大组划分为4个小组:安静对照组、末次运动后0 h(0 h)、3 h(3 h)、24 h(24 h)取材组。结果与结论:(1)大鼠心肌Toll样受体4蛋白表达在一次急性运动后呈持续高水平表达;4周、10周耐力训练后均出现一过性表达增高,高水平状态的持续时间缩短;(2)核因子κBp65表达在大鼠4周耐力训练后持续性升高,10周耐力训练只能引起末次运动后一过性升高,而运动后24 h组与安静组相比表达降低;(3)肌球蛋白重链1/2/4/6表达在大鼠一次急性运动后呈持续高水平表达,4周耐力训练后也呈持续性升高,10周耐力训练后则只出现一过性升高。结论:运动诱发Toll样受体4/核因子κBp65信号通路激活参与了运动心肌适应过程。
BACKGROUND： Acute myocardial ischemia and hypoxia can upregulate the expression of angiotensin II, toll-like receptor 4（TLR4） and nuclear factor κB（NFκB）. In TLR4 deficient mice, cardiac hypertrophy is found to be decreased in the presence of pressure overload, suggesting that TLR4/NFκBp65 is a key signaling pathway in the development and progression of cardiac hypertrophy. OBJECTIVE： To investigate the effect of TLR4/NFκBp65 signaling pathway activation on myocardial adaptation in rats subjected to graded endurance training of different exercise protocols.METHODS： Rats were randomly divided into three groups： a single bout of exercise, 4-and 10-week endurance training, respectively. Treadmill was used for exercise training. All three groups were subdivided into： control group and exercise groups euthanized 0, 3, and 24 hours after last training. RESULTS AND CONCLUSION： The expression level of TLR4 was sustained at high level after a single bout of exercise, but the expression level was increased only immediately after last training in 4 and 10 weeks of endurance in rats. The expression level of NFκBp65 showed a sustained increase in 4-week trained rats, but only transiently increased in 10-week trained rats after last run, and the expression was reduced in the 24-hour exercise group when compared with age-matched control group. The expression level of myosin heavy chain1/2/4/6 appeared to be continuously increased after a single bout of exercise and 4 weeks of endurance training, but was only transiently increased after 10 weeks of endurance training. The exercise-induced activation of TLR4/NFκBp65 signaling pathway may participate in the myocardial adaptation.
作者
顾伟玉
刘晓然
王智强
王蕴红
Gu Wei-yu;Liu Xiao-ran;Wang Zhi-qiang;Wang Yun-hong(School of Exercise Science and Health,Capital University of Physical Education and Sports,Beijing 100191,China)
出处
《中国组织工程研究》
CAS
北大核心
2018年第20期3201-3206,共6页
Chinese Journal of Tissue Engineering Research
基金
北京市教委科技面上项目(KM201310029001)
首都体育学院分子生物学研究平台项目(PXM2015_014206_000040
PXM2015_014206_000072)~~
