Muscle protein metabolism, nutritional control

作者：Mosoni Laurent^*

来源：Nutrition Clinique et Metabolisme, 2014, 28(1): 29-37.

DOI：10.1016/j.nupar.2013.12.003

• Insulin
• Leucine
• Muscle
• Protein synthesis
• Proteolysis

In order to preserve muscle mass, it is necessary to maintain a balance between protein synthesis and degradation. Among factors that control this balance, we focus on nutritional factors: insulin, amino acids, leucine, then we describe two recent concepts: 1) the stimulation threshold: it is necessary to ingest a threshold amount of amino acids and/or leucine to obtain a stimulation of protein synthesis, this amount being variable depending on the age or the physiological state of the subject; 2) the muscle full: about 2 hours after a meal, muscle protein synthesis stimulation stops, as if muscle was "full", and could not gain any more protein. The probable causes of this phenomenon are discussed. Finally, we explain that all these results were obtained in the short term, and that it is difficult to deduce long-term strategies efficient to maintain lean body mass during aging.

• 出版日期2014-2