Galactosyllactoses and Other Oligosaccharides in Human Milk

This summary has been adapted from Presence and Levels of Galactosyllactoses and Other Oligosaccharides in Human Milk and Their Variation during Lactation and According to Maternal Phenotype. Nutrients (2021) by Eussen et al.

Oligosaccharides in human breast milk are believed to be key to a child’s development, affecting growth (1), immunity (2), the functioning of the gastrointestinal tract (3) and the microbiota present in the gut (4). While there are reportedly over 1000 different types of oligosaccharides in breast milk, a relatively small group, the galactosyllactoses (GLs), have been found to be present (5), with specific isomers, β3’-GL and β6’-GL, presenting links with intestinal immunology and attenuated inflammation (6). The concentrations of oligosaccharides in breast milk can vary substantially, dependent on factors such as the stage of lactation and genetics (8). A strong genetic influence is the pattern of Secretor (Se) and Lewis (Le) blood group genes, which can be used the categorise breast milk into Groups I – IV (9). A collaborative research group based in the Netherlands and Germany collected breast milk samples from 347 European women from between one and four months postpartum, with a subgroup of 24 Dutch women who provided samples for up to a year. All samples were analysed for the presence and concentration of different GL isomers, as well as being categorised into one of Groups I – IV. The findings demonstrated that Group I samples contained the highest abundance of oligosaccharides, with Group IV containing only 60% of the amount. Across all groups, the total levels of oligosaccharides decreased over the first four months postpartum, with the concentrations of the different types also presenting temporal trends. β3’-GL and β6’-GL were found in over 75% of the samples tested. Using the samples supplied over a year, the absolute concentrations of β3’-GL and β6’-GL were shown to be significantly higher in Group IV, when compared to the other three Groups. It was also observed that Group II presented a significantly higher concentration of β3’-GL than Group I. However, while an effect of maternal phenotype was apparent, the concentrations of β3’-GL and β6’-GL were not influenced by lactation stage.

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References

1. Sprenger, N.; Lee, L.Y.; De Castro, C.A.; Steenhout, P.; Thakkar, S.K. Longitudinal change of selected human milk oligosaccharides and association to infants’ growth, an observatory, single center, longitudinal cohort study. PLoS ONE 2017, 12, e0171814.
2. Ayechu-Muruzabal, V.; van Stigt, A.H.; Mank, M.;Willemsen, L.E.M.; Stahl, B.; Garssen, J.; Van’t Land, B. Diversity of Human Milk Oligosaccharides and Effects on Early Life Immune Development. Front. Pediatr. 2018, 6, 239.
3. Bering, S.B. Human Milk Oligosaccharides to Prevent Gut Dysfunction and Necrotizing Enterocolitis in Preterm Neonates. Nutrients 2018, 10, 1461.
4. Musilova, S.; Rada, V.; Vlkova, E.; Bunesova, V. Beneficial effects of human milk oligosaccharides on gut microbiota. Benef. Microbes 2014, 5, 273–283.
5. Newburg, D.S.; Ko, J.S.; Leone, S.; Nanthakumar, N.N. Human Milk Oligosaccharides and Synthetic Galactosyloligosaccharides
6. Contain 30-, 4-, and 60-Galactosyllactose and Attenuate Inflammation in Human T84, NCM-460, and H4 Cells and Intestinal Tissue Ex Vivo. J. Nutr. 2016, 146, 358–367.
7. He, Y.; Liu, S.; Leone, S.; Newburg, D.S. Human colostrum oligosaccharides modulate major immunologic pathways of immature human intestine. Mucosal Immunol. 2014, 7, 1326–1339.
8. Thurl, S.; Munzert, M.; Henker, J.; Boehm, G.; Müller-Werner, B.; Jelinek, J.; Stahl, B. Variation of human milk oligosaccharides in relation to milk groups and lactational periods. Br. J. Nutr. 2010, 104, 1261–1271.
9. Thurl, S.; Henker, J.; Siegel, M.; Tovar, K.; Sawatzki, G. Detection of four human milk groups with respect to Lewis blood group dependent oligosaccharides. Glycoconj. J. 1997, 14, 795–799.