Institute of Sport, Exercise and Active Living, Victoria University, Melbourne, Australia.
Med Sci Sports Exerc. 2012 May;44(5):827-34. doi: 10.1249/MSS.0b013e318240067e.
We investigated the effects of acute and chronic repeated-sprint exercise (RSE) on the skeletal muscle messenger RNA (mRNA) expression and protein abundance/phosphorylation associated with mitochondrial biogenesis.
Ten healthy young adults (seven males, three females) performed the RSE trial, comprising three sets of 5 × 4-s maximal sprints on a nonmotorized treadmill, with a 20-s recovery between sprints and 4.5 min between sets. After 4 wk of repeated-sprint training, three times per week, participants repeated the RSE. A vastus lateralis muscle biopsy was obtained at rest, immediately after, and 1 and 4 h after RSE, before and after training. Venous blood lactate and glucose were measured at rest and during recovery. Real-time reverse transcriptase polymerase chain reaction and Western blot techniques were used to measure mRNA expression and protein abundance, respectively.
Acute RSE increased the phosphorylation of acetyl-CoA carboxylase (86%, effect size (ES) = 1.4 ± 0.8, P < 0.001) and Ca calmodulin-dependent protein kinase II (69%, ES = 0.7 ± 0.6). Peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α; 208%, ES = 1.5 ± 0.7, P < 0.001) and nuclear respiratory factor 1 (92%, ES = 0.7 ± 0.8) mRNA expression was increased after RSE. Four weeks of training increased the abundance of PGC-1α protein at rest (33%, ES = 0.9 ± 0.7).
Both acute and chronic RSE, despite only 60 s and 12 min of exercise, respectively, altered the molecular signaling associated with mitochondrial adaptations and PGC-1α mRNA expression in skeletal muscle. However, the small-to-moderate changes in resting PGC-1α protein abundance after training, together with the absence of changes in aerobic fitness, require further research to understand the functional significance of PGC-1α in response to RSE.
我们研究了急性和慢性重复冲刺运动（RSE）对与线粒体生物发生相关的骨骼肌信使 RNA（mRNA）表达和蛋白丰度/磷酸化的影响。
10 名健康的年轻人（7 名男性，3 名女性）进行了 RSE 试验，包括在非动力跑步机上进行 3 组 5×4 秒的最大冲刺，每组冲刺之间休息 20 秒，每组之间休息 4.5 分钟。经过 4 周每周 3 次的重复冲刺训练后，参与者重复进行 RSE。在 RSE 前和后、休息时、立即后以及 1 小时和 4 小时后，从股外侧肌中获取活检。在休息和恢复期间测量静脉血乳酸和葡萄糖。实时逆转录聚合酶链反应和 Western blot 技术分别用于测量 mRNA 表达和蛋白丰度。
急性 RSE 增加了乙酰辅酶 A 羧化酶的磷酸化（86%，效果大小（ES）=1.4±0.8，P<0.001）和钙调蛋白依赖性蛋白激酶 II（69%，ES=0.7±0.6）。过氧化物酶体增殖物激活受体 γ 共激活因子 1α（PGC-1α；208%，ES=1.5±0.7，P<0.001）和核呼吸因子 1（92%，ES=0.7±0.8）的 mRNA 表达在 RSE 后增加。4 周的训练增加了休息时 PGC-1α 蛋白的丰度（33%，ES=0.9±0.7）。
尽管急性 RSE 仅进行了 60 秒，慢性 RSE 仅进行了 12 分钟，但分别改变了与线粒体适应和骨骼肌中 PGC-1α mRNA 表达相关的分子信号。然而，训练后休息时 PGC-1α 蛋白丰度的小到中等变化，加上有氧适能没有变化，需要进一步研究以了解 PGC-1α 对 RSE 反应的功能意义。
