Gaur Shashank, Kuchan Matthew J, Lai Chron-Si, Jensen Soren K, Sherry Christina L
Abbott Nutrition, Columbus, OH; and.
Department of Animal Sciences, Aarhus University, Tjele, Denmark.
J Nutr. 2017 Jul;147(7):1301-1307. doi: 10.3945/jn.116.245134. Epub 2017 May 31.
The naturally occurring α-tocopherol stereoisomer α-tocopherol is known to be more bioactive than synthetic α-tocopherol (-α-tocopherol). However, the influence of this difference on the α-tocopherol stereoisomer profile of human milk is not understood. We investigated whether supplemental α-tocopherol or -α-tocopherol differentially affected the distribution of α-tocopherol stereoisomers in milk and plasma from lactating women. Eighty-nine lactating women aged 19-40 y and with a body mass index (in kg/m) ≤30 were randomly assigned at 4-6 wk postpartum to receive a daily supplement containing 45.5 mg -α-tocopherol acetate (ARAC), 22.8 mg -α-tocopherol acetate + 20.1 mg -α-tocopherol (MIX), or 40.2 mg α-tocopherol (RRR). Milk and plasma were analyzed for α-tocopherol structural isomers and α-tocopherol stereoisomers at baseline and after 6 wk supplementation with the use of chiral HPLC. There were no significant treatment group or time-dependent changes in milk or plasma α, γ, or δ-tocopherol. α-tocopherol was the most abundant stereoisomer in both milk and plasma in each group. Supplementation changed both milk and plasma percentage α-tocopherol (RRR > MIX > ARAC) ( < 0.05) and percentage non-α-tocopherol (ARAC > MIX > RRR) ( < 0.05). In the RRR group, percentage α-tocopherol increased in milk (mean ± SEM: 78% ± 2.3% compared with 82% ± 1.7%) ( 0.05) and plasma (mean ± SEM: 77% ± 1.8% compared with 87% ± 1%) ( 0.05). In contrast, the percentage α-tocopherol decreased in the MIX and ARAC groups (MIX, 0.05; ARAC, 0.0001), and percentage non-α-tocopherol stereoisomers increased (MIX, 0.05; ARAC, 0.0001) commensurate with an accumulation of α-tocopherol stereoisomers ( < 0.05) in both milk and plasma. Milk and plasma α-tocopherol was positively correlated at baseline ( = 0.67; 0.0001) and 6 wk ( = 0.80; 0.0001). The α-tocopherol supplementation strategy differentially affected the α-tocopherol milk and plasma stereoisomer profile in lactating women. α-tocopherol increased milk and plasma percentage α-tocopherol, whereas -α-tocopherol acetate reduced these percentages. Because α-tocopherol is the most bioactive stereoisomer, investigating the impact of supplement-driven changes in the milk α-tocopherol stereoisomer profile on the α-tocopherol status of breastfed infants is warranted.
已知天然存在的α-生育酚立体异构体α-生育酚比合成α-生育酚（-α-生育酚）具有更高的生物活性。然而，这种差异对人乳中α-生育酚立体异构体谱的影响尚不清楚。我们研究了补充α-生育酚或-α-生育酚是否会对哺乳期妇女乳汁和血浆中α-生育酚立体异构体的分布产生不同影响。89名年龄在19至40岁、体重指数（kg/m）≤30的哺乳期妇女在产后4至6周被随机分配，分别每日补充45.5毫克-α-生育酚醋酸酯（ARAC）、22.8毫克-α-生育酚醋酸酯 + 20.1毫克-α-生育酚（MIX）或40.2毫克α-生育酚（RRR）。在基线期和补充6周后，使用手性高效液相色谱法分析乳汁和血浆中的α-生育酚结构异构体和α-生育酚立体异构体。各治疗组在乳汁或血浆中的α、γ或δ-生育酚水平以及时间依赖性变化均无显著差异。α-生育酚是每组乳汁和血浆中含量最丰富的立体异构体。补充剂改变了乳汁和血浆中α-生育酚的百分比（RRR > MIX > ARAC）（P < 0.05）以及非α-生育酚的百分比（ARAC > MIX > RRR）（P < 0.05）。在RRR组中，乳汁中α-生育酚的百分比增加（均值±标准误：78% ± 2.3%，相比之下为82% ± 1.7%）（P < 0.05），血浆中也增加（均值±标准误：77% ± 1.8%，相比之下为87% ± 1%）（P < 0.05）。相反，MIX组和ARAC组中α-生育酚的百分比下降（MIX，P < 0.05；ARAC，P < 0.0001），非α-生育酚立体异构体的百分比增加（MIX，P < 0.05；ARAC，P < 0.0001），这与乳汁和血浆中α-生育酚立体异构体的积累相关（P < 0.05）。乳汁和血浆中的α-生育酚在基线期呈正相关（r = 0.67；P < 0.0001），在6周时也呈正相关（r = 0.80；P < 0.0001）。α-生育酚补充策略对哺乳期妇女乳汁和血浆中α-生育酚立体异构体谱有不同影响。α-生育酚增加了乳汁和血浆中α-生育酚的百分比，而-α-生育酚醋酸酯降低了这些百分比。由于α-生育酚是生物活性最高的立体异构体，因此有必要研究补充剂驱动的乳汁α-生育酚立体异构体谱变化对母乳喂养婴儿α-生育酚状态的影响。
