A research group at Tokyo University of Agriculture and Technology has revealed that hydrogen peroxide produced from amino acid metabolism in breast milk suppresses the diversity of the intestinal flora (intestinal flora) of infants.
The intestinal flora begins to form shortly after birth, and the flora pattern acquired during lactation remains unchanged throughout life.Breastfeeding mammals are expected to be involved in the formation of the gut microbiota during lactation.
In this study, we used mice lacking the amino acid metabolizing enzyme gene (LAO1), which is abundant in breast milk (LAO1-deficient mice), and the intestinal flora of the offspring changes depending on whether LA01 is contained in breast milk. I checked.As a result, most of the intestinal flora of pups that receive breast milk from normal mice was occupied by lactic acid bacteria, and while the diversity of the bacteria was suppressed, LAO1-deficient mice were breast-fed. Various bacteria were present in the intestinal flora of pups, which was similar to that of adults.It was also confirmed that LAO1 does not lose its function even in the digestive tract of infants, decomposes amino acids to produce hydrogen peroxide, and hydrogen peroxide exhibits antibacterial properties against bacteria other than lactic acid bacteria.That is, it is considered that hydrogen peroxide produced in the digestive tract of an infant is selected from the invading bacterial group and preferentially colonizes lactic acid bacteria in the intestine.
The biological significance of breast milk reducing the diversity of the intestinal flora of offspring during lactation is not yet known.However, by using the model mouse of this study, it is possible to investigate how the difference in the diversity of intestinal bacteria affects the biological function after birth.In addition, the results of this research may lead to the development of a method for controlling intestinal bacteria using active oxygen such as hydrogen peroxide.
