Researchers at DTU have shown for the first time that breast milk promotes a core group of health beneficial bacteria of the adult gut microbiota, setting the stage for next generation milk formula.
In a new study just published in the journal Nature Communications, researchers from DTU Bioengineering together with collaboration partners from Japan, surprisingly show that particularly health-promoting bacteria from the butyrate producing Roseburia-Eubacterium group consume specific complex sugars present in mother’s milk. It is surprising because it contradicts the belief that breast milk does not play a part in the establishment of the adult human gut microbiome.
This insight give the first hint into the extended role of specific complex sugars present in mother’s milk (termed human milk oligosaccharides or HMOs) and paves the way for the design of next generation novel milk formula targeting key bacteria that provide protection from inflammatory disorders and colorectal cancer.
The manufacturers that produce milk formula focus on developing milk additives that mainly promote Bifidobacteria prevalent in the infant gut microbiota. Up until now, this has made good sense, but Professor Maher Abou Hachem from DTU Bioengineering, who heads the study, believes this new finding provides good prospects for developing novel breast milk substitutes:
“Based on our discovery, manufacturers may carefully consider their exclusive focus on Bifidobacteria when developing infant formula. By adding specific complex sugars, they can create a product that helps babies transition to a healthy adult microbiome, predisposing them for healthy lives.”
"Based on our discovery, manufacturers may carefully consider their exclusive focus on Bifidobacteria when developing infant formula. By adding specific complex sugars, they can create a product that helps babies transition to a healthy adult microbiome, predisposing them for healthy lives."
Professor Maher Abou Hachem, DTU Bioengineering
The human gut microbiota (HGM) is composed of trillions of microbes and has a major impact on human health. Abnormalities within the HGM structure have been associated with various metabolic, immunological and neurological disorder, including diabetes and colorectal cancer.
The scaffold for a balanced and healthy HGM is established during infancy and perturbation of the early life HGM maturation have been associated with chronic metabolic or immunological diseases. Breast milk, especially HMOs, are a prime factor for the assembly of the early life HGM, owing to the promotion of growth of HMO specialist Bifidobacteria in the neonate gut.
During weaning, solid food and dietary fibers, mainly of plant origin, gradually replace HMOs in the infant’s diet. This results in a dramatic shift in the infant gut microbiota and the HMO specialized Bifidobacteria community is gradually replaced by a complex and diverse adult gut microbiota, capable of mediating protection from chronic inflammations, life style diseases and certain cancer forms, which makes this community essential for human wellbeing.
This critical window of the assembly of a healthy and resilient adult HGM during weaning offers a unique opportunity for therapeutic interventions to overcome imbalance in early life that may have life-long negative health outcome for the host. The question if HMOs might also effect this crucial transition by interacting with bacteria from the adult HGM during weaning has until now remained unexplored.
This study however, provides evidence for a new potential role for HMOs beyond the establishment of the neonate microbiota, by promoting growth of a paramount group of health-relevant bacteria during weaning to become abundant and prevalent members of the healthy adult gut microbiota. It also spurs the question of whether breast milk plays an even larger role in the establishment of a healthy adult human gut microbiota:
“We are now seeking funding to investigate this more systematically; there may be other types of bacteria that interacts with various components of breast milk. It could all help to design the next generation of infant formula, thereby helping to lay the foundation for health," says Michael Pichler who has done the research for the study as part of his PhD study.
Read the study Butyrate producing colonic Clostridiales metabolise human milk oligosaccharides and cross feed on mucin via conserved pathways in Nature Communications
Read the story behind the study in this Nature Microbiology community blog