University of Munich Medical Centre, Zentralklinikum Augsburg, Germany.
J Pediatr Gastroenterol Nutr. 2012 Mar;54(3):353-63. doi: 10.1097/MPG.0b013e31823c3bfd.
Long-chain polyunsaturated fatty acid (LC-PUFA) enrichment of preterm infant formulas is recommended to meet high demands. Dietary LC-PUFA may inhibit endogenous LC-PUFA synthesis, thus limiting their benefit. We investigated effects of different docosahexaenoic acid (DHA) intakes on plasma and erythrocyte fatty acids and endogenous LC-PUFA synthesis in preterm infants.
Forty-two preterm infants (birth weight 1000-2200 g) were randomized double-blind to preterm formulas with γ-linolenic acid (0.4%) and arachidonic acid (AA, 0.1%) but different DHA contents (A: 0.04%, B: 0.33%, C: 0.52%); 24 received human milk (HM: 0.51% AA, 0.38% DHA, nonrandomized). Blood was sampled on study days 0, 14, and 28. Uniformly C-labeled linoleic acid (2 mg/kg) and α-linolenic acid (1 mg/kg) were applied orally on day 26 and blood samples collected 48 hours later.
On day 28, group A had the lowest and group C the highest plasma phospholipid concentrations of eicosapentaenoic acid and DHA. Erythrocyte phospholipid DHA was lowest in group A, but comparable in groups B, C, and HM. Plasma and erythrocyte AA were lower in formula groups than in HM. DHA intake had no effect on DHA synthesis. LC-PUFA synthesis was lower in HM infants.
DHA supply dose dependently increased plasma DHA. Formula DHA levels of 0.33% matched plasma DHA status of infants fed HM. LC-PUFA synthesis was lower in infants fed HM than formulas with different DHA and low AA contents. With the LC-PUFA supplementation used, DHA in formulas did not inhibit AA or DHA synthesis.
推荐在早产儿配方奶粉中添加长链多不饱和脂肪酸（LC-PUFA）以满足高需求。饮食中的 LC-PUFA 可能会抑制内源性 LC-PUFA 的合成，从而限制其益处。我们研究了不同二十二碳六烯酸（DHA）摄入量对早产儿血浆和红细胞脂肪酸以及内源性 LC-PUFA 合成的影响。
42 名早产儿（出生体重 1000-2200g）随机分为两组，分别接受添加 γ-亚麻酸（0.4%）和花生四烯酸（AA，0.1%）但 DHA 含量不同的早产儿配方奶粉（A：0.04%，B：0.33%，C：0.52%）；24 名接受人乳（HM：0.51% AA，0.38% DHA，非随机）。在研究第 0、14 和 28 天采血。在第 26 天给婴儿口服均匀标记的亚油酸（2mg/kg）和α-亚麻酸（1mg/kg），48 小时后采集血样。
第 28 天，A 组血浆二十碳五烯酸和 DHA 的磷脂浓度最低，C 组最高。A 组红细胞磷脂 DHA 最低，但 B、C 和 HM 组相似。与 HM 组相比，配方奶组血浆和红细胞 AA 较低。DHA 摄入量对 DHA 合成没有影响。HM 组婴儿 LC-PUFA 合成较低。
DHA 供给量与血浆 DHA 水平呈正相关。0.33%的配方奶粉 DHA 水平与喂养 HM 的婴儿的血浆 DHA 状态相匹配。与不同 DHA 和低 AA 含量的配方奶粉相比，HM 喂养的婴儿 LC-PUFA 合成较低。在所使用的 LC-PUFA 补充剂中，配方奶粉中的 DHA 不会抑制 AA 或 DHA 的合成。
