Table3_A young child formula supplemented with a synbiotic mixture of scGOS/lcFOS and Bifidobacterium breve M-16V improves the gut microbiota and iron status in healthy toddlers.xlsx

Early-life gut microbiota development depends on a highly synchronized microbial colonization process in which diet is a key regulator. Microbiota transition toward a more adult-like state in toddlerhood goes hand in hand with the transition from a milk-based diet to a family diet. Microbiota development during the first year of life has been extensively researched; however, studies during toddlerhood remain sparse. Young children's requirement for micronutrients, such as dietary iron, is higher than adults. However, their intake is usually sub-optimal based on regular dietary consumption. The Child Health and Residence Microbes (CHaRM) study, conducted as an adjunct to the GUMLi (Growing Up Milk “Lite”) trial, was a double-blind randomized controlled trial to investigate the effects on body composition of toddler milk compared to unfortified standard cow's milk in healthy children between 1 and 2 years of age in Brisbane (Australia). In this trial, fortified milk with reduced protein content and added synbiotics [Bifidobacterium breve M-16V, short-chain galactooligosaccharides, and long-chain fructooligosaccharides (ratio 9:1)] and micronutrients were compared to standard unfortified cow's milk. In the present study, the effects of the intervention on the gut microbiota and its relationship with iron status in toddlers were investigated in a subset of 29 children (18 in the Active group and 11 in the Control group) who completed the CHaRM study. The toddler microbiota consisted mainly of members of the phyla Firmicutes, Bacteroidota, and Actinobacteriota. The abundance of the B. breve species was quantified and was found to be lower in the Control group than in the Active group. Analysis of blood iron markers showed an improved iron status in the Active group. We observed a positive correlation between Bifidobacterium abundance and blood iron status. PICRUSt, a predictive functionality algorithm based on 16S ribosomal gene sequencing, was used to correlate potential microbial functions with iron status measurements. This analysis showed that the abundance of predicted genes encoding for enterobactin, a class of siderophores specific to Enterobacteriaceae, is inversely correlated with the relative abundance of members of the genus Bifidobacterium. These findings suggest that healthy children who consume a young child formula fortified with synbiotics as part of a healthy diet have improved iron availability and absorption in the gut and an increased abundance of Bifidobacterium in their gut microbiome.

婴幼儿期肠道微生物群的发育依赖于一种高度同步的微生物定殖过程，其中饮食是其关键调节因子。微生物群在幼儿期向更成熟状态的转变与从以乳制品为主的饮食向家庭饮食的转变相伴随。对生命第一年内微生物群发育的研究已相当广泛；然而，关于幼儿期的相关研究仍较为稀缺。幼儿对微量元素，如膳食铁的需求高于成人。然而，根据常规饮食摄入，他们的摄入量通常不足。Child Health and Residence Microbes（CHaRM）研究作为GUMLi（成长型乳“轻”）试验的辅助研究，是一项双盲随机对照试验，旨在调查在布里斯班（澳大利亚）1至2岁健康儿童中，与未强化标准牛奶相比，幼儿牛奶对身体成分的影响。在此试验中，与添加了合成生物制剂（双歧杆菌 breve M-16V、短链半乳寡糖和长链果寡糖（比例为9:1））和微量元素的蛋白质含量降低的强化牛奶相比，标准未强化牛奶。在本研究中，对干预措施对肠道微生物群及其与幼儿铁状态之间的关系在29名完成CHaRM研究的儿童子集中进行了调查（活动组18名，对照组11名）。幼儿微生物群主要由厚壁菌门、拟杆菌门和放线菌门的成员组成。对B. breve种类的丰度进行了量化，发现其在对照组中的丰度低于活动组。血液铁标志物的分析显示，活动组的铁状态得到改善。我们观察到双歧杆菌丰度与血液铁状态之间存在正相关。PICRUSt，一种基于16S核糖体基因测序的预测功能算法，用于将潜在微生物功能与铁状态测量相关联。此分析显示，编码肠菌素（Enterobacteriaceae特有的一类铁载体）的预测基因的丰度与双歧杆菌属成员的相对丰度呈负相关。这些发现表明，健康儿童在健康饮食中摄入含有合成生物制剂的幼儿配方奶粉，可以提高肠道中铁的可用性和吸收，并在他们的肠道微生物群中增加双歧杆菌的丰度。