Stautemas Jan, Everaert Inge, Lefevere Filip B D, Derave Wim
Department of Movement & Sports Sciences, Ghent University, Ghent, Belgium.
Front Nutr. 2018 Aug 17;5:70. doi: 10.3389/fnut.2018.00070. eCollection 2018.
The ergogenic response following long-term ingestion of β-alanine shows a high inter-individual variation. It is hypothesized that this variation is partially caused by a variable pharmacokinetic response induced by inferior dosing strategies. At this point most supplements are either taken in a fixed amount (× g), as is the case with β-alanine, or relative to body weight (× g per kg BW), but there is currently neither consensus nor a scientific rationale on why these or other dosing strategies should be used. The aim of this study is to objectify and understand the variation in plasma pharmacokinetics of a single oral β-alanine dose supplemented as either a fixed or a weight-relative dose (WRD) in an anthropometric diverse sample. An anthropometric diverse sample ingested a fixed dose (1,400 mg) ( = 28) and a WRD of β-alanine (10 mg/kg BW) ( = 34) on separate occasions. Blood samples were taken before and at nine time points (up to 4 h) after β-alanine ingestion in order to establish a pharmacokinetic profile. Incremental area under the curve (iAUC) was calculated by the trapezoidal rule. Plasma β-alanine was quantified using HPLC-fluorescence. The variation coefficient (CV%) of the iAUC was 35.0% following ingestion of 1,400 mg β-alanine. Body weight explained 30.1% of the variance and was negatively correlated to iAUC ( = -0.549; = 0.003). Interestingly, the CV% did not decrease with WRD (33.2%) and body weight was positively correlated to iAUC in response to the WRD ( = 0.488; = 0.003). Both dosing strategies evoked an equally high inter-individual variability in pharmacokinetic plasma profile. Strikingly, while body weight explained a relevant part of the variation observed following a fixed dose, correction for body weight did not improve the homogeneity in β-alanine plasma response. We suggest to put more effort into the optimization of easy applicable and scientifically justified personalized dosing strategies.
长期摄入β-丙氨酸后的促力反应存在高度的个体间差异。据推测，这种差异部分是由较差的给药策略引起的可变药代动力学反应所致。目前，大多数补充剂要么以固定量（×克）服用，β-丙氨酸就是如此，要么相对于体重（每千克体重×克）服用，但目前对于为何应采用这些或其他给药策略，既没有共识，也没有科学依据。本研究的目的是在一个人体测量多样化的样本中，客观化并理解单次口服β-丙氨酸剂量（以固定剂量或体重相对剂量（WRD）补充）的血浆药代动力学差异。一个人体测量多样化的样本在不同时间分别摄入固定剂量（1400毫克）（n = 28）和β-丙氨酸的体重相对剂量（10毫克/千克体重）（n = 34）。在摄入β-丙氨酸之前以及之后的九个时间点（长达4小时）采集血样，以建立药代动力学曲线。通过梯形法则计算曲线下增量面积（iAUC）。使用高效液相色谱-荧光法对血浆β-丙氨酸进行定量。摄入1400毫克β-丙氨酸后，iAUC的变异系数（CV%）为35.0%。体重解释了30.1%的方差，且与iAUC呈负相关（r = -0.549；P = 0.003）。有趣的是，CV%在体重相对剂量时并未降低（33.2%），且体重与体重相对剂量时的iAUC呈正相关（r = 0.488；P = 0.003）。两种给药策略在药代动力学血浆曲线方面均引发了同样高的个体间变异性。引人注目的是，虽然体重解释了固定剂量后观察到的部分变异，但对体重进行校正并未改善β-丙氨酸血浆反应的同质性。我们建议加大力度优化易于应用且有科学依据的个性化给药策略。
