Hall Elliott C R, Semenova Ekaterina A, Bondareva Elvira A, Andryushchenko Liliya B, Larin Andrey K, Cięszczyk Pawel, Generozov Edward V, Ahmetov Ildus I
Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool L3 5AF, UK.
Department of Molecular Biology and Genetics, Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, 119435 Moscow, Russia.
Genes (Basel). 2022 Feb 23;13(3):397. doi: 10.3390/genes13030397.
Branched-chain amino acid (BCAA) levels are associated with skeletal muscle cross-sectional area (CSA). Serum BCAA levels are enhanced by whey protein supplementation (WPS), and evidence in clinical populations suggests an association of single nucleotide polymorphisms (SNPs) with BCAA metabolite levels. It is not known whether the same SNPs are associated with the ability to catabolise BCAAs from exogenous sources, such as WPS. The present study investigated whether possessing a higher number of alleles associated with increased BCAA metabolites correlates with muscle fiber CSA of m. vastus lateralis in physically active participants, and whether any relationship is enhanced by WPS. Endurance-trained participants (n = 75) were grouped by self-reported habitual WPS consumption and genotyped for five SNPs (PPM1K rs1440580, APOA5 rs2072560, CBLN1 rs1420601, DDX19B rs12325419, and TRMT61A rs58101275). Body mass, BMI, and fat percentage were significantly lower and muscle mass higher in the WPS group compared to Non-WPS. The number of BCAA-increasing alleles was correlated with fiber CSA in the WPS group (r = 0.75, p < 0.0001) and was stronger for fast-twitch fibers (p = 0.001) than slow-twitch fibers (p = 0.048). Similar results remained when corrected for multiple covariates (age, physical activity, and meat and dairy intake). No correlation was found in the Non-WPS group. This study presents novel evidence of a positive relationship between BCAA-increasing alleles and muscle fiber CSA in athletes habitually consuming WPS. We suggest that a high number of BCAA-increasing alleles improves the efficiency of WPS by stimulation of muscle protein synthesis, and contributes to greater fiber CSA.
支链氨基酸（BCAA）水平与骨骼肌横截面积（CSA）相关。补充乳清蛋白（WPS）可提高血清BCAA水平，临床人群中的证据表明单核苷酸多态性（SNP）与BCAA代谢物水平有关。目前尚不清楚相同的SNP是否与从外源性来源（如WPS）分解代谢BCAAs的能力有关。本研究调查了在身体活跃的参与者中，拥有与增加的BCAA代谢物相关的等位基因数量是否与股外侧肌的肌纤维CSA相关，以及WPS是否会增强这种关系。耐力训练的参与者（n = 75）根据自我报告的习惯性WPS摄入量进行分组，并对五个SNP（PPM1K rs1440580、APOA5 rs2072560、CBLN1 rs1420601、DDX19B rs12325419和TRMT61A rs58101275）进行基因分型。与非WPS组相比，WPS组的体重、BMI和脂肪百分比显著更低，肌肉质量更高。在WPS组中，增加BCAA的等位基因数量与纤维CSA相关（r = 0.75，p < 0.0001），并且对快肌纤维（p = 0.001）的相关性强于慢肌纤维（p = 0.048）。在校正多个协变量（年龄、身体活动以及肉类和奶制品摄入量）后，结果相似。在非WPS组中未发现相关性。本研究提供了新的证据，表明在习惯性摄入WPS的运动员中，增加BCAA的等位基因与肌纤维CSA之间存在正相关关系。我们认为，大量增加BCAA的等位基因通过刺激肌肉蛋白质合成提高了WPS的效率，并有助于增加纤维CSA。
