Kuchan Matthew J, Moulton Christopher J, Dyer Roger A, Jensen Soren K, Schimpf Karen J, Innis Sheila M
Discovery Research and Development, Abbott Nutrition, Columbus, OH.
BC Children's Hospital Research Institute, Department of Pediatrics, University of British Columbia, Vancouver, Canada.
Curr Dev Nutr. 2018 Jun 15;2(8):nzy055. doi: 10.1093/cdn/nzy055. eCollection 2018 Aug.
The naturally occurring α-tocopherol (α-T) stereoisomer, -α-tocopherol (-α-T), is known to be more bioactive than -α-tocopherol (-α-T), a synthetic racemic mixture of 8 stereoisomers. There is widespread use of -α-T in maternal supplements.
The aim of the study was to thoroughly describe the α-T stereoisomer profile of human milk.
We measured the α-T stereoisomer profile in milk from 2 cohorts of women: a cohort of 121 women who provided milk on days 30 and 60 of lactation (study 1) and a separate cohort of 51 women who provided milk on days 10, 21, 71, and 120 of lactation (study 2).
-α-T was the predominant stereoisomer ( < 0.0001) in all samples in both studies despite a large intrasubject range in total α-T (0.7-22 μg/mL). On average, -α-T comprised 73-76% of total α-T, but average values for the synthetic stereoisomers were , 8-14%; , 6-8%; , 5-6%; and the sum of stereoisomers (Σ), 3-5%. Despite the predominance of -α-T, the sum of the synthetic stereoisomers comprised as much as 48% of total α-T. We calculated the ratio of to the sum of the synthetic ( + + ) stereoisomers (s) to assess the degree to which is favored in milk Consistent with discrimination among 2 stereoisomers in mammary tissue, /s2 values ranged from 2.8 to 3.6, as opposed to the expected ratio of 0.33 if there was no discrimination. However, the to s ratio did not correlate with milk α-T concentration, but both components of the ratio did.
-α-T is the predominant stereoisomer in human milk, concentrations of synthetic 2 stereoisomers were notable, and the relation between milk total α-T and stereoisomer profile is complex. Due to the wide range found in milk α-T stereoisomer profile, investigation into its impact on α-T status and functional outcomes in breastfed infants is warranted.
天然存在的α-生育酚（α-T）立体异构体，即-α-生育酚（-α-T），已知比-α-生育酚（-α-T）更具生物活性，后者是8种立体异构体的合成外消旋混合物。-α-T在孕产妇补充剂中广泛使用。
本研究的目的是全面描述人乳中的α-T立体异构体谱。
我们测量了两组女性乳汁中的α-T立体异构体谱：一组121名女性在哺乳期第30天和第60天提供乳汁（研究1），另一组51名女性在哺乳期第10天、第21天、第71天和第120天提供乳汁（研究2）。
在两项研究的所有样本中，-α-T都是主要的立体异构体（<0.0001），尽管个体内总α-T的范围很大（0.7 - 22μg/mL）。平均而言，-α-T占总α-T的73 - 76%，但合成立体异构体的平均值分别为，8 - 14%；，6 - 8%；，5 - 6%；以及立体异构体总和（Σ），3 - 5%。尽管-α-T占主导地位，但合成立体异构体的总和占总α-T的比例高达48%。我们计算了与合成（+ +）立体异构体总和（s）的比值，以评估在乳汁中更受青睐的程度。与乳腺组织中两种立体异构体的区分一致，/s2值范围为2.8至3.6，而如果没有区分，预期比值为0.33。然而，与s的比值与乳汁α-T浓度无关，但该比值的两个组成部分均相关。
-α-T是人乳中的主要立体异构体，合成的2种立体异构体的浓度显著，且乳汁总α-T与立体异构体谱之间的关系复杂。鉴于人乳α-T立体异构体谱的范围很广，有必要研究其对母乳喂养婴儿α-T状态和功能结局的影响。
