Myofibrillar protein synthesis rates are increased in chronically exercised skeletal muscle despite decreased anabolic signaling.
Myofibrillar protein synthesis rates are increased in chronically exercised skeletal muscle despite decreased anabolic signaling.
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DOI：
10.1038/s41598-022-11621-x
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发表时间：
2022-05-09
影响因子：
4.6
通讯作者：
中科院分区：
文献类型：
--
作者：
对急性抗阻运动的分子反应被很好地表征。然而，细胞信号如何随着时间的推移而变化，以调节长期运动训练的慢性适应性，目前还不太清楚。我们研究了急性和慢性离心负荷后几个时间点的合成代谢信号和肌肉蛋白质合成率。刺激成年大鼠胫骨前肌，共6组，每组10次，分别于0、6、18、48 h取材。在最后一组动物中，在第一次运动后48小时进行第二次运动，并在6小时后收集肌肉（总共54小时）。在第二个实验中，大鼠在2周的时间内进行了4次运动。在第一次回合后6小时，合成代谢信号在18至48小时之间恢复到基线水平。有趣的是，第二回合后6小时mTORC1活性显著低于第一回合。在长期运动的大鼠中，我们发现基线合成代谢信号减少，而肌原纤维蛋白合成（MPS）在最后一次运动后48小时显著增加。MPS的增加发生在肌纤维大小或质量没有变化的情况下。总之，我们发现合成代谢信号在第二轮急性阻力型运动后已经减少。此外，长期暴露于阻力型运动训练导致基础合成代谢信号降低，但总体MPS率增加。
The molecular responses to acute resistance exercise are well characterized. However, how cellular signals change over time to modulate chronic adaptations to more prolonged exercise training is less well understood. We investigated anabolic signaling and muscle protein synthesis rates at several time points after acute and chronic eccentric loading. Adult rat tibialis anterior muscle was stimulated for six sets of ten repetitions, and the muscle was collected at 0 h, 6 h, 18 h and 48 h. In the last group of animals, 48 h after the first exercise bout a second bout was conducted, and the muscle was collected 6 h later (54 h total). In a second experiment, rats were exposed to four exercise sessions over the course of 2 weeks. Anabolic signaling increased robustly 6 h after the first bout returning to baseline between 18 and 48 h. Interestingly, 6 h after the second bout mTORC1 activity was significantly lower than following the first bout. In the chronically exercised rats, we found baseline anabolic signaling was decreased, whereas myofibrillar protein synthesis (MPS) was substantially increased, 48 h after the last bout of exercise. The increase in MPS occurred in the absence of changes to muscle fiber size or mass. In conclusion, we find that anabolic signaling is already diminished after the second bout of acute resistance type exercise. Further, chronic exposure to resistance type exercise training results in decreased basal anabolic signaling but increased overall MPS rates.
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影响因子：
2.5
作者：
KUIPERS, H
通讯作者：
KUIPERS, H
影响因子：
2.9
作者：
Gilda JE;Gomes AV
通讯作者：
Gomes AV
DOI：
10.1113/jp272857
发表时间：
2016-12-15
期刊：
The Journal of physiology
影响因子：
--
作者：
Brook MS;Wilkinson DJ;Mitchell WK;Lund JN;Phillips BE;Szewczyk NJ;Greenhaff PL;Smith K;Atherton PJ
通讯作者：
Atherton PJ
影响因子：
5.5
作者：
Bondesen, BA;Mills, ST;Pavlath, GK
通讯作者：
Pavlath, GK
DOI：
10.1016/j.bbagen.2005.12.023
发表时间：
2006-05-01
影响因子：
3
作者：
Busch, Robert;Kim, Yoo-Kyeong;Hellerstein, Marc K.
通讯作者：
Hellerstein, Marc K.