ECSS Paris 2023: OP-PN06
INTRODUCTION: Sarcopenia, the age-related loss of muscle mass and function (1), is associated with 'anabolic resistance', a reduced muscle protein synthesis response to an anabolic stimulus, such as protein intake (2). We hypothesize that, analogously to an OGTT for glucose, the metabolome response after protein ingestion is a measure of protein digestion speed and anabolic sensitivity, since a rapid rise in amino acids indicates rapid digestion, while fast clearance suggests high protein synthesis or anabolism. To test this, we compared the metabolome response to 20 g of whey protein in young individuals and in individuals with sarcopenia. METHODS: Twenty-three participants, including young healthy adults (n = 12; 25.4 ± 2.0 years) and (pre-)sarcopenic elderly (n = 11; 82.9 ± 6.2 years), received a 20 g bolus of whey protein after overnight fasting. We collected venous blood at 0, 60, and 120 minutes post-ingestion and analyzed blood plasma using LC/MS untargeted metabolomics with HILIC separation in both positive and negative ionisation modes. Following log₁₀ transformation, median normalisation and ComBat batch correction, we applied a mixed effect ANOVA (time × group) with Benjamini–Hochberg FDR correction (q < 0.05). RESULTS: A total of 2,968 metabolites were detected, 201 of which were annotated. Data revealed no significant interaction (time x group) for any measured annotated metabolite (all ≈ 0.99), indicating that the kinetics of the whey protein response are similar across age groups. We identified significant time effects (q < 0.05) for a broad range of metabolites, including essential amino acids such as leucine (q < 10-10), valine (q = 5.06 x 10-6), and threonine (q = 6.15 x10-8), as well as various fatty acids (e.g., FA 16:1, q = 1.06 x 10-5). Significant group differences (q < 0.05) independent of protein intake were found in metabolites such as trimethylamine N-oxide (q = 0.019), tryptophan (q = 0.0038), and N(6)-methyladenosine (q= 0.019), highlighting distinct baseline metabolic profiles in (pre)sarcopenic adults. Next, we will perform additional analyses to test whether the metabolome's response to protein ingestion reflects digestion speed and anabolic sensitivity. CONCLUSION: Ingestion of whey protein not only causes a transient rise of amino acids but also of other metabolites. Additional analyses will ascertain whether this can be utilized to estimate the anabolic sensitivity of an individual. Furthermore, this data shows that protein ingestion not only affects plasma amino acids but also other metabolites. References: 1 Cruz-Jentoft et al., Age Ageing, 2019 2 Aragon et al., Nutr Rev, 2023
Read CV Tim HaversECSS Paris 2023: OP-PN06
INTRODUCTION: Pre-sleep protein supplementation can be a strategy of athletes to achieve daily protein requirements and to sustain amino acid supply during sleep. Among protein sources, casein has traditionally been regarded as the optimal choice for pre-sleep ingestion, in contrast, whey protein is rapidly digested, producing a faster but more transient aminoacidemia. Although whey and casein proteins have been directly compared with respect to overnight muscle protein synthesis, showing no differences between these milk protein fractions. Food intake before sleep can affect sleep quality, however, the effects of different milk protein fractions on sleep quality have not been directly compared. METHODS: In a randomized, double-blind, cross-over trial, 9 young, healthy and resistance trained men (n=5) and women (n=4) (age: 24±2 y; BMI: 24.4±2.9 kg/m2) performed resistance exercise sessions on 3 occasions followed by ingestions of either 40 g of whey (WHEY), casein (CASEIN) protein, or an isocaloric maltodextrin control (CON) 30 min before bedtime. Sleep quality was assessed using actigraphy, heart rate variability (HRV) and a subjective sleep questionnaire. Gastrointestinal symptoms were monitored, exercise performance and delayed onset of muscle soreness (DOMS) were evaluated the next day. Data are presented as median and interquartile range (IQR). Friedman tests were used to assess treatment differences between WHEY, CASEIN and CON, post-hoc comparisons were performed using Dunn’s multiple comparisons test. Effect sizes were estimated using Kendall’s coefficient of concordance (W), with values of ~0.1, ~0.3, and ≥0.5 indicating small, moderate, and large effects, respectively. RESULTS: Pre-sleep whey protein ingestion improved sleep-onset latency (9.0 [8.0–11.0]; 16.0 [10.0–19.0]; 19.0 [15.0–27.0] min in WHEY, CASEIN, and CON, respectively; W=0.51), sleep efficiency (96% [96–98]; 96% [94–96]; 93% [91–96]; W=0.42), total sleep time (400 [374–404]; 390 [365–412]; 363 [358–412] min; W=0.42) and subjective sleep rating (8.0 [7.0–9.0]; 7.0 [5.0–7.0]; 6.0 [5.0–7.0]; W=0.81) compared to CON (all P<0.05) but not CASEIN (all P>0.05). WHEY led to a significant reduction in DOMS 12 and 24 h post-training when compared to CON (P<0.05; both W=0.64). There were no differences in HRV variables, gastrointestinal symptoms and exercise performance between treatments (all P>0.05). CONCLUSION: Pre-sleep whey protein ingestion may enhance sleep quality after resistance training and reduce muscle soreness without affecting gastrointestinal symptoms and exercise performance in healthy young adults. Future research should consider extending the supplementation period to examine long-term effects on performance.
Read CV Thorben AussiekerECSS Paris 2023: OP-PN06
INTRODUCTION: Load-induced skeletal muscle hypertrophy is thought to be regulated by subcellular protein interactions, specifically mechanistic target of rapamycin (mTOR)-lysosome colocalization and translocation to the cell periphery. However, evidence supporting this model is largely derived from studies examining the acute ~3 h period. This narrow window does not reflect typical daily feeding patterns consisting of multiple meals, which serve as subsequent anabolic stimuli over a 24-hour period. Therefore, current evidence provides an incomplete understanding of how subcellular protein complexes interact to drive changes in muscle protein synthesis over the course of an entire day. We compared post-exercise changes in subcellular protein interactions in males and females after consuming one large meal of protein a day (OMAD), or three smaller meals of protein (SPLIT) over a 24-hour period. METHODS: Healthy young males and females (n = 12 per group) were randomized to consume either one meal (OMAD) or three meals (SPLIT) comprising a total of 1.6 g/kg of protein/day, following a single bout of whole-body resistance exercise (RE). Skeletal muscle biopsies of the vastus lateralis were taken to examine subcellular protein complex interactions. Muscle sections were stained for mTOR complex 1, lysosomal associated membrane protein 2 (LAMP2), and laminin, then imaged and quantified. Pearson’s product-moment correlation coefficients were used to quantify interactions and are expressed as fold change from baseline. RESULTS: A significant group x time interaction (p < 0.01) was found for LAMP2-laminin colocalization. At 14.5h post-RE, LAMP2-laminin colocalization differed significantly between OMAD and SPLIT (p < 0.0001). Specifically, colocalization was significantly reduced from baseline in OMAD (p < 0.0001), whereas SPLIT did not differ from baseline (p = 0.991). No significant main effects of group or group x time interaction were detected for mTOR-LAMP2 colocalization (p = 0.326 and p = 0.369, respectively), or for mTOR-laminin colocalization (p = 0.768 and p = 0.225, respectively). CONCLUSION: Subcellular interactions between mTOR and the lysosome were subtly but differentially impacted by the SPLIT and OMAD feeding patterns. While previous work found mTOR-LAMP2 interactions to peak ~1-3 hours following anabolic stimuli, no significant changes were observed here, likely because our post-exercise/first meal biopsy occurred 4.5 hours after anabolic stimuli. Therefore, the window for significant changes in mTOR-LAMP2 and mTOR-laminin interactions may have been missed. Notably, a SPLIT feeding pattern seemed to better maintain the interaction between lysosomes and the cell periphery when compared with OMAD, possibly due to the influx of amino acids following the third meal. Thus, anabolism-associated lysosomal positioning at the cell border is affected by meal pattern and presumably amino acid availability, and may occur independently of detectable changes in mTOR localization.
Read CV James NewboldECSS Paris 2023: OP-PN06