Sarcopenia commonly occurs in the elderly and patients with wasting diseases. The main reason is an imbalance in protein metabolism (protein degradation exceeding protein synthesis). It causes a serious decline in muscle strength and motion ability, even leading to long-term bed rest. Recent studies indicate that nutritional support is beneficial for ameliorating sarcopenia and restoring muscle function. This review will summarize the classical mechanisms of protein nutritional support for alleviating sarcopenia, such as modulating the ubiquitin–proteasome system, oxidative response, and cell autophagy, as well as the potential new mechanisms, including altering miRNA profiles and gut microbiota. In addition, the clinical application and outcome of protein nutritional support in the elderly and patients with wasting diseases are also introduced. Protein nutritional support is expected to provide new approaches for the prevention and adjuvant therapy of sarcopenia.

中文翻译：

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蛋白质营养支持：预防和治疗肌肉减少症的经典和潜在新机制

肌肉减少症通常发生在老年人和疾病消瘦的患者中。主要原因是蛋白质代谢失衡（蛋白质降解超过蛋白质合成）。它会导致肌肉力量和运动能力的严重下降，甚至导致长期卧床休息。最近的研究表明，营养支持有助于减少肌肉减少症和恢复肌肉功能。这篇综述将总结蛋白质营养支持减轻肌肉减少症的经典机制，例如调节遍在蛋白-蛋白酶体系统，氧化反应和细胞自噬，以及潜在的新机制，包括改变miRNA和肠道菌群。此外，还介绍了老年人和消瘦疾病患者中蛋白质营养支持的临床应用和结果。