Project Title: Impact of Feeding Type and Nutrient Fortification on the Gut Microbiome of Very Low Birth Weight Infants

Short Title: microDoMINO

Principal Investigators: Deborah O'Connor PhD RD, Sharon Unger MD FRCPC

Co-Investigators: Alexander Kiss PhD, David Mack MD FRCPC, Gabriel Moreno-Hagelsieb PhD, Prakesh Shah MSc MBBS MD DCH MRCP FRCPC, Philip Sherman MD FRCPC FAAP,

Alain Stintzi PhD

Funding Source: Canadian Institutes of Health Research (CIHR) 2013-2016, Physicians' Services Incorporated (PSI) Foundation 2013-2015 

In term infants, mother's milk is the best nutrition as it contains live cells and indigestible sugars that promote colonization of the infant gut with protective rather than pathogenic bacteria.  Colonization of the gut with beneficial bacteria is believed to be a key mechanism responsible for the inverse relationship between mother's milk intake and morbidity.  Unfortunately VLBW infants have altered bacterial colonization as a result of several factors including antibiotic use and living in a crowded neonatal intensive care unit. Gut colonization may be more favourable in VLBW infants fed mother's milk, however this is not known as most research has focused on term infants.  Additionally, most mothers of VLBW infants are unable to express enough milk to entirely feed their infants and need to supplement with either formula or donor milk. Little is known about the impact of diet (mother's milk, donor milk, formula, nutrient fortification) on bacterial colonization of the gut in the VLBW infant and a lack of understanding exists with respect to the gut microbial community and its metabolic functions.  Emerging evidence suggests the overall taxonomic profile might be as important as the presence of a particular species given that the gut microbiota is an ecosystem whose function depends on the interaction among microbes.  It is critical to address these gaps in order to determine how to best feed VLBW infants to improve gut colonization. 

The goal of microDoMINO is to characterize bacteria colonizing the gut in VLBW infants fed mother's milk, donor milk or formula and to study metabolic activities carried out by gut bacteria to define the potential physiological roles that the microbiome plays in the gut and how these may change with different feeding regimes.  These findings will provide a key reference for optimal gut colonization in VLBW infants and guide policy development for nutritional strategies to best promote the health of fragile infants.