Effects of a Formula with scGOS/lcFOS (9:1) and Glycomacropeptide (GMP) Supplementation on the Gut Microbiota of Very Preterm Infants

Abstract

Microbial colonization of very preterm (VPT) infants is detrimentally affected by the complex interplay of physiological, dietary, medical, and environmental factors. The aim of this study was to evaluate the effects of an infant formula containing the specific prebiotic mixture of scGOS/lcFOS (9:1) and glycomacropeptide (GMP) on the composition and function of VPT infants' gut microbiota. Metagenomic analysis was performed on the gut microbiota of VPT infants sampled at four time points: 24 h before the trial and 7, 14, and 28 days after the trial. Functional profiling was aggregated into gut and brain modules (GBMs) and gut metabolic modules (GMMs) based on the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. Enterococcus faecium, Escherichia coli, Klebsiella aerogenes, and Klebsiella pneumoniae were dominant species in both the test group and the control group. After the 4-week intervention, the abundance of Bifidobacterium in the test group was significantly increased. We found two GBMs (quinolinic acid synthesis and kynurenine degradation) and four GMMs (glutamine degradation, glyoxylate bypass, dissimilatory nitrate reduction, and preparatory phase of glycolysis) were significantly enriched in the test group, respectively. The results of this study suggested that formula enriched with scGOS/lcFOS (9:1) and GPM is beneficial to the intestinal microecology of VPT infants.

Keywords: glycomacropeptide; metagenomics; prebiotics; preterm.

Figure 1

The study cohort. A total of 72 very preterm infants were included in this study, among which 37 infants were given a test formula containing prebiotics and sialic acid. Fecal samples were collected 24 h before, 7 days after, 14 days after, and 28 days after the intervention.

Figure 2

The effect of formula supplemented with prebiotics and sialic acid on microbial diversity in the VPT infant gut. PCoA of Bray–Curtis distances based on the profile of genera, * indicates difference at p value < 0.05, ** indicates difference at p value < 0.01 (a); comparison of genus numbers between the test group and control group (b); alpha diversity of gut microbiota measured by the Shannon index (c).

Figure 3

Relative abundance of gut microbiota at the genus level (a) and species level (b). Comparison of the relative abundance of Bifidobacterium between the test group and the control group (c).

Figure 4

Comparison of gut and brain modules (GBMs) and gut metabolic modules (GMMs) between the test group and the control group. Quinolinic acid synthesis (a), kynurenine degradation (b), glutamine degradation (c), glyoxylate bypass (d), dissimilatory nitrate reduction (e) and preparatory phase of glycolysis (f).