Exercise Metabolism Research Group,Department of Kinesiology,McMaster University,Canada.
Physiology,Exercise and Nutrition Research Group,Faculty of Health Sciences and Sport,University of Stirling,Scotland,FK9 4LA,UK.
Proc Nutr Soc. 2018 Feb;77(1):20-31. doi: 10.1017/S002966511700194X. Epub 2017 Aug 29.
The age-related loss of skeletal muscle mass and function is caused, at least in part, by a reduced muscle protein synthetic response to protein ingestion. The magnitude and duration of the postprandial muscle protein synthetic response to ingested protein is dependent on the quantity and quality of the protein consumed. This review characterises the anabolic properties of animal-derived and plant-based dietary protein sources in older adults. While approximately 60 % of dietary protein consumed worldwide is derived from plant sources, plant-based proteins generally exhibit lower digestibility, lower leucine content and deficiencies in certain essential amino acids such as lysine and methionine, which compromise the availability of a complete amino acid profile required for muscle protein synthesis. Based on currently available scientific evidence, animal-derived proteins may be considered more anabolic than plant-based protein sources. However, the production and consumption of animal-derived protein sources is associated with higher greenhouse gas emissions, while plant-based protein sources may be considered more environmentally sustainable. Theoretically, the lower anabolic capacity of plant-based proteins can be compensated for by ingesting a greater dose of protein or by combining various plant-based proteins to provide a more favourable amino acid profile. In addition, leucine co-ingestion can further augment the postprandial muscle protein synthetic response. Finally, prior exercise or n-3 fatty acid supplementation have been shown to sensitise skeletal muscle to the anabolic properties of dietary protein. Applying one or more of these strategies may support the maintenance of muscle mass with ageing when diets rich in plant-based protein are consumed.
骨骼肌质量和功能随年龄的增长而下降，至少部分原因是蛋白质摄入后肌肉蛋白质合成反应减少。摄入蛋白质后，餐后肌肉蛋白质合成反应的幅度和持续时间取决于消耗蛋白质的数量和质量。本综述描述了老年人动物源性和植物性饮食蛋白质来源的合成代谢特性。虽然全世界大约 60%的膳食蛋白质来自植物来源，但植物性蛋白质通常表现出较低的消化率、较低的亮氨酸含量和某些必需氨基酸（如赖氨酸和蛋氨酸）的缺乏，这限制了完整氨基酸谱的可用性，而完整氨基酸谱是肌肉蛋白质合成所必需的。根据目前现有的科学证据，动物源性蛋白质可能被认为比植物性蛋白质来源更具合成代谢作用。然而，动物源性蛋白质来源的生产和消费与温室气体排放增加有关，而植物性蛋白质来源可能被认为更具环境可持续性。从理论上讲，可以通过摄入更大剂量的蛋白质或通过组合各种植物性蛋白质来提供更有利的氨基酸谱来补偿植物性蛋白质较低的合成代谢能力。此外，亮氨酸共摄入可以进一步增强餐后肌肉蛋白质合成反应。最后，先前的运动或 n-3 脂肪酸补充已被证明可以使骨骼肌对膳食蛋白质的合成代谢特性敏感。当摄入富含植物性蛋白质的饮食时，应用这些策略中的一种或多种可能有助于维持肌肉质量随年龄的增长。
