2'-岩藻糖基乳糖和乳-N-新四糖、半乳糖寡糖以及人乳寡糖谱对肯尼亚婴儿铁吸收的影响。

The effects of 2'-fucosyllactose and lacto-N-neotetraose, galacto-oligosaccharides, and maternal human milk oligosaccharide profile on iron absorption in Kenyan infants.

机构信息

Laboratory of Human Nutrition, Department of Health Sciences and Technology, ETH Zurich, Zurich, Switzerland.

Laboratory of Human Nutrition, Department of Health Sciences and Technology, ETH Zurich, Zurich, Switzerland; Department of Physiology and Zurich Center for Integrative Human Physiology, University of Zurich, Zurich, Switzerland.

出版信息

Am J Clin Nutr. 2023 Jan;117(1):64-72. doi: 10.1016/j.ajcnut.2022.10.005. Epub 2022 Dec 15.

DOI:10.1016/j.ajcnut.2022.10.005

PMID:36789945

Abstract

BACKGROUND

Whether prebiotic human milk oligosaccharides (HMO), such as 2'-fucosyllactose (2'-FL) and lacto-N-neotetraose (LNnT), enhance iron absorption in infants is unknown. Moreover, whether maternal HMO profile affects absorption of iron fortificants or the effects of prebiotic galacto-oligosaccharides (GOS) and/or HMO on iron absorption is uncertain.

OBJECTIVES

The aim of this study was to test whether consumption of 3.0 g GOS or HMO enhances iron absorption from iron-fortified maize porridge in partially breastfed Kenyan infants and whether maternal HMO profile modulates these effects.

METHODS

In a randomized, prospective crossover study, 55 infants (aged 8-12 mo) were fed test meals fortified with 1 of the following: 1) 5.0 mg iron as Fe-labeled ferrous fumarate (FeFum); 2) 5.0 mg iron as FeFum and 3.0 g GOS (FeFum+GOS); and 3) 5.0 mg iron as FeFum and 2.0 g 2'-FL and 1.0 g LNnT (FeFum+HMO). Fractional iron absorption (FIA) was assessed by erythrocyte incorporation of iron isotopes. HMO profiles were determined by capillary gel electrophoresis with laser-induced florescence detection. Data were analyzed with mixed-effect models, and iron dialyzability was measured in vitro.

RESULTS

Of the 55 infants included, 49 were fed as instructed. FIA from the FeFum+GOS group [median (IQR) 22.2% (16.5%-25.9%)] was higher than that from the FeFum group [12.5% (9.5%-20.9%)] (P = 0.005). FIA from the FeFum+HMO group was 13.3% (7.1%-24.4%) and did not differ from the FeFum group (P = 0.923). Maternal HMO profile did not predict FIA or modulate the effects of GOS or HMO on FIA. Iron dialyzability ratios at pH 2 of FeFum+GOS to FeFum and FeFum+HMO to FeFum were 2.1 and 0.9 (P = 0.001 and P = 0.322), respectively.

CONCLUSIONS

In Kenyan infants consuming FeFum-fortified maize porridge, co-provision of 3.0 g GOS increased FIA by 78%, whereas co-provision of 3.0 g HMO did not affect FIA. Variations in maternal HMO profile, including secretor and Lewis phenotype, did not predict FIA. These data argue against a physiologic role for 2'-FL and LNnT in facilitating iron absorption in infancy. The study was registered at clinicaltrials.gov as NCT04163406 (https://clinicaltrials.gov/ct2/show/NCT04163406).

摘要

背景

目前尚不清楚母乳低聚糖（HMO）等益生元是否能增强婴儿对铁的吸收，例如 2'-岩藻糖基乳糖（2'-FL）和乳-N-新四糖（LNnT）。此外，母体 HMO 谱是否会影响铁强化剂的吸收，以及是否益生元半乳糖-低聚糖（GOS）和/或 HMO 对铁吸收有影响，这些都不确定。

目的

本研究旨在测试 3.0 g GOS 或 HMO 是否能增强肯尼亚部分母乳喂养婴儿对铁强化玉米粥中铁的吸收，并测试母体 HMO 谱是否会调节这些影响。

方法

在一项随机、前瞻性交叉研究中，55 名 8-12 月龄婴儿食用了以下 1 种强化铁的测试餐食：1）5.0 mg 铁作为 Fe 标记富马酸亚铁（FeFum）；2）5.0 mg 铁作为 FeFum 和 3.0 g GOS（FeFum+GOS）；和 3）5.0 mg 铁作为 FeFum 和 2.0 g 2'-FL 和 1.0 g LNnT（FeFum+HMO）。通过红细胞掺入铁同位素来评估铁的分数吸收率（FIA）。采用毛细管凝胶电泳结合激光诱导荧光检测法测定 HMO 谱。采用混合效应模型进行数据分析，并在体外测量铁的可透析性。

结果

在纳入的 55 名婴儿中，有 49 名按要求接受了喂养。与 FeFum 组相比，FeFum+GOS 组的 FIA [中位数（IQR）22.2%（16.5%-25.9%）]更高（P=0.005）。FeFum+HMO 组的 FIA 为 13.3%（7.1%-24.4%），与 FeFum 组无差异（P=0.923）。母体 HMO 谱并不能预测 FIA，也不能调节 GOS 或 HMO 对 FIA 的影响。FeFum+GOS 与 FeFum 和 FeFum+HMO 与 FeFum 在 pH 2 时的铁可透析率分别为 2.1 和 0.9（P=0.001 和 P=0.322）。

结论

在肯尼亚食用铁强化玉米粥的婴儿中，同时提供 3.0 g GOS 可使 FIA 增加 78%，而同时提供 3.0 g HMO 则不会影响 FIA。母体 HMO 谱的变化，包括分泌型和 Lewis 表型，并不预示 FIA。这些数据表明，2'-FL 和 LNnT 在促进婴儿铁吸收方面没有生理作用。该研究在 clinicaltrials.gov 上注册为 NCT04163406（https://clinicaltrials.gov/ct2/show/NCT04163406）。