New Study: Infant Gut Health Must Focus on Microbiome Function, Not Diversity

DAVIS, Calif., April 14, 2020 /PRNewswire/ -- The concepts of ecology, conservation, and restoration typically conjure images of natural woodlands, water systems and air quality. However, a new peer-reviewed perspective by Evolve BioSystems is taking a page from ecology playbooks in an effort to assist neonatologists and other pediatric health care professionals in assessing the state of the infant gut microbiome, which plays a significant role in immune development and metabolism in infants.

The paper, Integrating the ecosystem services framework to define dysbiosis of the breastfed infant gut: the role of B. infantis and human milk oligosaccharides, appears in the Nutrition and Microbes section of Frontiers in Nutrition. 

The conventional definition of microbiome health had previously been based on diversity – that is, the number and variety of different bacteria in the gut. However, the diversity model presents a simplistic view and has limited value because it cannot be classified as good or bad. Typically, older children and adults are thought to require a diverse array of bacteria to support gut health and to break down a wide range of foods. However, infants who are breastfed receive their nutrition from breastmilk, and a specialized bacterium has evolved to help infants maximize the utility of this single source of nutrition. Numerous studies have identified Bifidobacterium longum subspecies infantis (B. infantis) as the critical beneficial bacterium associated with infant gut health and immune development.

"There's widespread misperception that the health of the infant gut microbiome is defined by the diversity of bacteria present; however, infants don't need a range of bacteria, they simply need the right bacteria for gut health," said Rebbeca Duar, PhD, lead study author and senior scientist in microbiology for Evolve BioSystems, Inc. "Our recommendations are the first to enable neonatologists and pediatricians to objectively determine infant gut health based on the presence of the bacteria most critical to gut function."

Inspired from the Outside, In

Dr. Duar and her colleagues looked outside of human biology to the field of ecology for a model that provided the most objective approach to defining functional ecological health. The team applied the ecosystem services model, an approach used by environmental ecologists to identify and assess the benefits humans receive from  natural environmental ecosystems – supporting services for structure, provisioning services to feed the system, and regulating services to maintain system balance.

Applied to the infant gut microbiome, the microorganisms that live in the gastrointestinal tract of newborns, the approach can identify and assess the presence and impact of specific bacteria that structure, feed and regulate gut health, thus guiding care strategy for infants. The gut microbiome plays a pivotal role in the development and regulation of the immune system and develops early in life from exposure to bacteria from the mother during childbirth. However, high prevalence of Cesarean deliveries and high incidence of antibiotic use negatively impact infant exposure to these bacteria, thus hampering the development of a healthy gut microbiome and immune system.

Dr. Duar and team validated the hypothesis by analyzing the impact of feeding a specific strain of probiotic bacteria to breastfed infants: activated B. infantis EVC001. Applying the ecosystem services model, the team validated the critical functional role B. infantis EVC001 plays in breaking down human oligosaccharides from breastmilk to release energy for the infant, regulate immune development, and prevent the growth of pathogenic gut bacteria.

"With a firm, objective definition of gut dysbiosis based on biological function, not diversity, we've set a new bar for evaluating the health of the infant gut and established a path by which clinicians can more effectively assess the impact of medical interventions and specific probiotics," said Steven Frese, PhD, director of microbiology and bioinformatics at Evolve and the corresponding author of the study. "Together with new research on the role that the microbiome plays in early life, our team at Evolve is setting a new standard in the infant gut microbiome space and how this community can shape infant health, both short and long term."

About Evolve BioSystems, Inc.
Evolve BioSystems, Inc. is a privately held microbiome company dedicated to researching solutions to establish, restore, and maintain a healthy gut microbiome. Evolve is a portfolio company of the Bill & Melinda Gates Foundation and Horizons Ventures, the venture division of the Li Ka Shing Foundation. Evolve is a spin-off from the Foods for Health Institute (FFHI) at the University of California, Davis and builds on more than a decade of research into understanding the unique partnership of the infant gut microbiome and breast milk components.

SOURCE Evolve Biosystems