Cavallaro Nicole Landa, Garry Jamie, Shi Xu, Gerszten Robert E, Anderson Ellen J, Walford Geoffrey A
Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA, USA.
Metabolism & Nutrition Research, Clinical Research Center, Massachusetts General Hospital, Boston, MA, USA.
Food Nutr Res. 2016 Jan 14;60:28592. doi: 10.3402/fnr.v60.28592. eCollection 2016.
Elevated fasting levels of branched chain amino acids (BCAAs: valine, isoleucine, leucine) in venous blood are associated with a variety of metabolic impairments, including increased risk of type 2 diabetes (T2D). Fasting BCAA levels are influenced by non-dietary factors. However, it is unknown whether fasting BCAAs can be altered through manipulation of dietary intake alone.
To test whether a specific dietary intervention, using differences in BCAA intake, alters fasting BCAA levels independent of other factors.
Five healthy male volunteers underwent 4 days of a low and 4 days of a high BCAA content dietary intervention (ClinicalTrials.gov [NCT02110602]). All food and supplements were provided. Fasting BCAAs were measured from venous blood samples by mass spectrometry at baseline and after each intervention.
Diets were isocaloric; contained equal percentages of calories from carbohydrate, fats, and protein; and differed from each other in BCAA content (1.5±0.1 vs. 14.0±0.6 g for valine; 4.5±0.9 g vs. 13.8±0.5 g for isoleucine; 2.1±0.2 g vs. 27.1±1.0 g for leucine; p<0.0001 for all). Fasting valine was significantly lower (p=0.02) and fasting isoleucine and leucine were numerically lower following the low BCAA content vs. the high BCAA content diet levels. The inter-individual response to the dietary interventions was variable and not explained by adherence.
Short-term dietary manipulation of BCAA intake led to modest changes in fasting levels of BCAAs. The approach from our pilot study can be expanded to test the metabolic implications of dietary BCAA manipulation.
静脉血中支链氨基酸（BCAAs：缬氨酸、异亮氨酸、亮氨酸）的空腹水平升高与多种代谢障碍有关，包括2型糖尿病（T2D）风险增加。空腹BCAA水平受非饮食因素影响。然而，仅通过控制饮食摄入是否能改变空腹BCAAs尚不清楚。
测试一种特定的饮食干预，即利用BCAA摄入量的差异，独立于其他因素改变空腹BCAA水平。
五名健康男性志愿者接受了4天低BCAA含量饮食干预和4天高BCAA含量饮食干预（ClinicalTrials.gov [NCT02110602]）。所有食物和补充剂均由研究方提供。在基线和每次干预后，通过质谱法从静脉血样本中测量空腹BCAAs。
饮食热量相等；碳水化合物、脂肪和蛋白质提供的热量百分比相同；仅BCAA含量不同（缬氨酸：1.5±0.1克对14.0±0.6克；异亮氨酸：4.5±0.9克对13.8±0.5克；亮氨酸：2.1±0.2克对27.1±1.0克；所有p<0.0001）。与高BCAA含量饮食水平相比，低BCAA含量饮食后空腹缬氨酸显著降低（p=0.02），空腹异亮氨酸和亮氨酸在数值上较低。个体对饮食干预的反应存在差异，且不能用依从性来解释。
短期饮食控制BCAA摄入量导致空腹BCAAs水平有适度变化。我们初步研究的方法可以扩展，以测试饮食中BCAA控制的代谢影响。
