Our previous study indicated that whey protein hydrolysate (WPH) showed effective anti-fatigue properties, but its regulatory mechanism on recovery from exercise in mice is unclear. In the present study, we divided the mice into control, WP, and WPH groups and allowed them to rest for 1 h and 24 h after exercise, respectively. The changes in muscle metabolites of mice in the recovery period were investigated using metabolomics techniques. The results showed that the WPH group significantly up-regulated 94 muscle metabolites within 1 h of rest, which was 1.96 and 2.61 times more than the control and WP groups, respectively. In detail, significant decreases in TCA cycle intermediates, lipid metabolites, and carbohydrate metabolites were observed in the control group during exercise recovery. In contrast, administration with WP and WPH enriched more amino acid metabolites within 1 h of rest, which might provide a more comprehensive metabolic environment for muscle repair. Moreover, the WPH group remarkably stimulated the enhancement of lipid, carbohydrate, and vitamin metabolites in the recovery period which might provide raw materials and energy for anabolic reactions. The result of the western blot further demonstrated that WPH could promote muscle repair via activating the Sestrin2/Akt/mTOR/S6K signaling pathway within 1 h of rest. These findings deepen our understanding of the regulatory mechanisms by WPH to promote muscle recovery and may serve as a reference for comprehensive assessments of protein supplements on exercise.

中文翻译：

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非靶向代谢组学揭示小鼠运动恢复过程中肌肉代谢物的变化以及乳清蛋白和乳清蛋白水解物促进肌肉修复的机制

我们之前的研究表明，乳清蛋白水解物（WPH）显示出有效的抗疲劳特性，但其对小鼠运动恢复的调节机制尚不清楚。在本研究中，我们将小鼠分为对照组、WP组和WPH组，并分别让它们在运动后休息1小时和24小时。采用代谢组学技术研究恢复期小鼠肌肉代谢物的变化。结果显示，WPH组在休息1小时内显着上调了94种肌肉代谢物，分别是对照组和WP组的1.96倍和2.61倍。具体来说，在运动恢复过程中，对照组的 TCA 循环中间体、脂质代谢物和碳水化合物代谢物显着减少。相比之下，给予WP和WPH在休息1小时内富集了更多的氨基酸代谢物，这可能为肌肉修复提供更全面的代谢环境。此外，WPH组在恢复期显着刺激脂质、碳水化合物和维生素代谢的增加，这可能为合成代谢反应提供原料和能量。 Western blot结果进一步证明WPH可以在休息1小时内通过激活Sestrin2/Akt/mTOR/S6K信号通路促进肌肉修复。这些研究结果加深了我们对WPH促进肌肉恢复的调节机制的理解，并可为运动中蛋白质补充剂的综合评估提供参考。