Justesen Thomas Ehlig Hjermind, Jespersen Simon Elmer, Tagmose Thomsen Thomas, Holm Lars, van Hall Gerrit, Agergaard Jakob
Institute of Sports Medicine Copenhagen, Department of Orthopedic Surgery, Copenhagen University Hospital-Bispebjerg and Frederiksberg, 2400 Copenhagen NV, Denmark.
Center for Healthy Ageing, Department of Clinical Medicine, University of Copenhagen, 2200 Copenhagen N, Denmark.
Nutrients. 2022 Oct 22;14(21):4442. doi: 10.3390/nu14214442.
Sarcopenia is a multifactorial disease that limits autonomy for the growing elderly population. An optimal amount of dietary protein has shown to be important to maintain muscle mass during aging. Yet, the optimal distribution of that dietary protein has not been fully clarified. The aim of the present study was to examine whether an even, compared to a skewed, distribution of daily dietary protein leads to higher muscle protein synthesis and amino acid utilization. Twelve healthy males and twelve healthy females aged between 65 and 80 years were block randomized to either an even (EVEN, = 12) or skewed (SKEWED, = 12) dietary protein distribution for three daily main meals. Seven days of habituation were followed by three trial days, which were initiated by oral intake of deuterium oxide (DO). The dietary protein throughout all trial meals was intrinsically labelled with H-phenylalanine. Blood samples were drawn daily, and muscle biopsies were taken before and at the end of the trial to measure muscle protein synthesis (FSR) and muscle protein incorporation of the dietary-protein-derived tracer. Muscle protein FSR was no different between the two groups (EVEN 2.16 ± 0.13%/day and SKEWED 2.23 ± 0.09%/day, = 0.647), and the muscle protein incorporation of the intrinsically labeled H-phenylalanine tracer was not different between the two groups (EVEN 0.0049 ± 0.0004 MPE% and SKEWED 0.0054 ± 0.0003 MPE%, = 0.306). In conclusion, the daily distribution pattern of the dietary protein did not affect muscle protein synthesis or the utilization of dietary protein.
肌肉减少症是一种多因素疾病，限制了日益增多的老年人口的自主性。已表明适量的膳食蛋白质对于在衰老过程中维持肌肉质量很重要。然而，该膳食蛋白质的最佳分配尚未完全阐明。本研究的目的是检验与不均衡分配相比，每日膳食蛋白质的均匀分配是否会导致更高的肌肉蛋白质合成和氨基酸利用。12名年龄在65至80岁之间的健康男性和12名健康女性被整群随机分为每日三餐膳食蛋白质均匀分配组（EVEN，n = 12）或不均衡分配组（SKEWED，n = 12）。经过7天的适应期后进行3天的试验期，试验期由口服氧化氘（DO）开始。所有试验餐中的膳食蛋白质均用H-苯丙氨酸进行内源性标记。每天采集血样，并在试验开始前和结束时进行肌肉活检，以测量肌肉蛋白质合成（FSR）和膳食蛋白质衍生示踪剂的肌肉蛋白质掺入情况。两组之间的肌肉蛋白质FSR无差异（EVEN组为2.16±0.13%/天，SKEWED组为2.23±0.09%/天，P = 0.647），两组之间内源性标记的H-苯丙氨酸示踪剂的肌肉蛋白质掺入也无差异（EVEN组为0.0049±0.0004 MPE%，SKEWED组为0.0054±0.0003 MPE%，P = 0.306）。总之，膳食蛋白质的每日分配模式不影响肌肉蛋白质合成或膳食蛋白质的利用。
