Danone Nutricia Research, 3584 CT Utrecht, The Netherlands.
Cambridge Centre for Sport and Exercise Sciences, Anglia Ruskin University, Cambridge CB1 1PT, UK.
Nutrients. 2023 May 30;15(11):2569. doi: 10.3390/nu15112569.
P4, a specific combination of dairy proteins (whey and casein) and plant-based protein isolates (pea and soy), has been shown to provide a more balanced amino acid (AA) profile than its single constituent proteins; however, less is known about how this translates to muscle protein synthesis (MPS). The aim of this study was to investigate the effect of P4 compared to whey or casein against fasted control on MPS. C57BL/6J mice, aged 25 months, were fasted overnight, followed by oral gavage of either whey, P4, casein, or water as a fasted control. Thirty minutes after ingestion, puromycin (0.04 µmol∙g bodyweight) was subcutaneously injected; 30-min thereafter, mice were sacrificed. MPS was measured by the SUnSET method, and signalling proteins were determined in the left-tibialis anterior (TA) muscle by the WES technique. AA composition was determined in plasma and right-TA muscle. Dried blood spots (DBS) were analysed for postprandial AA dynamics at 10, 20, 45, 60 min. MPS was 1.6-fold increased with whey ( = 0.006) and 1.5-fold with P4 compared to fasted ( = 0.008), while no change was seen with casein. This was confirmed by a significant increase of phosphorylated/total ratio of 4E-BP1 for both whey ( = 0.012) and P4 ( = 0.001). No changes were observed in p70S6K and mTOR phosphorylation/total ratio with whey or P4. Intramuscular leucine levels were lower for P4 (0.71 µmol∙g dry weight) compared to whey (0.97 µmol∙g dry weight) ( = 0.0007). Ten minutes postprandial, DBS showed significantly increased blood AA levels of BCAAs, histidine, lysine, threonine, arginine, and tyrosine for P4 versus fasted. In conclusion, a hybrid mix of dairy and plant-based proteins (P4) resulted in a MPS response that was similar to whey protein in aged mice after fasting. This suggests that other anabolic triggers beyond leucine or the well-balanced amino acid profile and bioavailability of the blend benefit stimulation of MPS.
P4 是一种特定的乳制品蛋白质（乳清蛋白和酪蛋白）和植物性蛋白质分离物（豌豆和大豆）的混合物，与单一蛋白质成分相比，它提供了更平衡的氨基酸（AA）谱；然而，关于这如何转化为肌肉蛋白质合成（MPS）的信息较少。本研究旨在研究 P4 与乳清蛋白或酪蛋白相比，在空腹对照状态下对 MPS 的影响。25 月龄的 C57BL/6J 小鼠隔夜禁食，随后口服灌胃乳清蛋白、P4、酪蛋白或水作为空腹对照。摄入后 30 分钟，皮下注射嘌呤霉素（0.04 µmol·g 体重）；30 分钟后，处死小鼠。通过 SUnSET 法测量 MPS，并用 WES 技术测定左胫骨前肌（TA）中的信号蛋白。通过等离子体和右-TA 肌肉测定 AA 组成。分析干血斑（DBS）以研究 10、20、45、60 分钟时的餐后 AA 动力学。与空腹相比，乳清蛋白使 MPS 增加了 1.6 倍（ = 0.006），P4 使 MPS 增加了 1.5 倍（ = 0.008），而酪蛋白则没有变化。这通过乳清蛋白（ = 0.012）和 P4（ = 0.001）中 4E-BP1 的磷酸化/总比值的显著增加得到了证实。与乳清蛋白或 P4 相比，p70S6K 和 mTOR 磷酸化/总比值没有变化。与乳清蛋白相比，P4 使肌肉内亮氨酸水平降低（0.71 µmol·g 干重）（ = 0.0007）。餐后 10 分钟，DBS 显示与空腹相比，P4 使 BCAAs、组氨酸、赖氨酸、苏氨酸、精氨酸和酪氨酸的血液 AA 水平显著增加。总之，在老年小鼠禁食后，乳制品和植物性蛋白质（P4）的混合混合物引起的 MPS 反应与乳清蛋白相似。这表明，除了亮氨酸或混合的平衡氨基酸谱和生物利用度之外，其他合成代谢触发因素也有利于刺激 MPS。
