Influence of Maternal Milk on the Neonatal Intestinal Microbiome

Abstract

The intestinal microbiome plays an important role in maintaining health throughout life. The microbiota develops progressively after birth and is influenced by many factors, including the mode of delivery, antibiotics, and diet. Maternal milk is critically important to the development of the neonatal intestinal microbiota. Different bioactive components of milk, such as human milk oligosaccharides, lactoferrin, and secretory immunoglobulins, modify the composition of the neonatal microbiota. In this article, we review the role of each of these maternal milk-derived bioactive factors on the microbiota and how this modulation of intestinal bacteria shapes health, and disease.

Keywords: breast milk; human milk oligosaccharides; lactoferrin; maternal milk; neonatal microbiome; secretory IgA.

Figure 1

Maternal milk components shape the microbiota. Enterobacteriaceae is one of the first colonizers of the infant intestine and is controlled by secretory IgA (sIgA) from milk, prior to the infant’s own production of sIgA. Lactoferrin inhibits many types of Enterobacteriaceae by binding iron and preventing epithelial adhesion. Human milk oligosaccharides (HMOs) support the outgrowth of Bifidobacteriaceae, which can convert HMOs into Short Chain Fatty Acids, which are an important energy source for the intestinal epithelium and also contribute to immunoregulation. HMOs also serve as decoy receptors limiting bacterial association with the intestinal epithelium. Together these components induce an environment conducive to the colonization of the strict anaerobes that will compose the healthy adult intestinal microbiome.