The stepwise assembly of the neonatal virome is modulated by breastfeeding.

2020

470-474

2020 May

1476-4687

<p>The gut of healthy human neonates is usually devoid of viruses at birth, but quickly becomes colonized, which-in some cases-leads to gastrointestinal disorders. Here we show that the assembly of the viral community in neonates takes place in distinct steps. Fluorescent staining of virus-like particles purified from infant meconium or early stool samples shows few or no particles, but by one month of life particle numbers increase to 10 per gram, and these numbers seem to persist throughout life. We investigated the origin of these viral populations using shotgun metagenomic sequencing of virus-enriched preparations and whole microbial communities, followed by targeted microbiological analyses. Results indicate that, early after birth, pioneer bacteria colonize the infant gut and by one month prophages induced from these bacteria provide the predominant population of virus-like particles. By four months of life, identifiable viruses that replicate in human cells become more prominent. Multiple human viruses were more abundant in stool samples from babies who were exclusively fed on&nbsp;formula milk compared with those fed partially or fully on breast milk, paralleling reports that breast milk can be protective against viral infections. Bacteriophage populations also differed depending on whether or not the infant was breastfed. We show that the colonization of the infant gut is stepwise, first mainly by temperate bacteriophages induced from pioneer bacteria, and later by viruses that replicate in human cells; this second phase is modulated by breastfeeding.</p>

10.1038/s41586-020-2192-1

Nature

32461640

Bacterial colonization reprograms the neonatal gut metabolome.

2020

2020 Apr 13

2058-5276

<p>Initial microbial colonization and later succession in the gut of human infants are linked to health and disease later in life. The timing of the appearance of the first gut microbiome, and the consequences for the early life metabolome, are just starting to be defined. Here, we evaluated the gut microbiome, proteome and metabolome in 88 African-American newborns using faecal samples collected in the first few days of life. Gut bacteria became detectable using molecular methods by 16 h after birth. Detailed analysis of the three most common species, Escherichia coli, Enterococcus faecalis and Bacteroides vulgatus, did not suggest a genomic signature for neonatal gut colonization. The appearance of bacteria was associated with reduced abundance of approximately 50 human proteins, decreased levels of free amino acids and an increase in products of bacterial fermentation, including acetate and succinate. Using flux balance modelling and in vitro experiments, we provide evidence that fermentation of amino acids provides a mechanism for the initial growth of E. coli, the most common early colonizer, under anaerobic conditions. These results provide a deep characterization of the first microbes in the human gut and show how the biochemical environment is altered by their appearance.</p>

10.1038/s41564-020-0694-0

Nat Microbiol

32284564

A Social Media Peer Group for Mothers To Prevent Obesity from Infancy: The Grow2Gether Randomized Trial.

2017

2017 May 30

2153-2176

<p><strong>BACKGROUND: </strong>Few studies have addressed obesity prevention among low-income families whose infants are at increased obesity risk. We tested a Facebook peer-group intervention for low-income mothers to foster behaviors promoting healthy infant growth.</p>

<p><strong>METHODS: </strong>In this randomized controlled trial, 87 pregnant women (Medicaid insured, BMI ≥25 kg/m(2)) were randomized to the Grow2Gether intervention or text message appointment reminders. Grow2Gether participants joined a private Facebook group of 9-13 women from 2 months before delivery until infant age 9 months. A psychologist facilitated groups featuring a curriculum of weekly videos addressing feeding, sleep, parenting, and maternal well-being. Feasibility was assessed using the frequency and content of participation, and acceptability using surveys. Maternal beliefs and behaviors and infant growth were assessed at birth, 2, 4, 6, and 9 months. Differences in infant growth between study arms were explored. We conducted intention-to-treat analyses using quasi-least-squares regression.</p>

<p><strong>RESULTS: </strong>Eighty-eight percent (75/85) of intervention participants (42% (36/85) food insecure, 88% (75/85) black) reported the group was helpful. Participants posted 30 times/group/week on average. At 9 months, the intervention group had significant improvement in feeding behaviors (Infant Feeding Style Questionnaire) compared to the control group (p = 0.01, effect size = 0.45). Intervention group mothers were significantly less likely to pressure infants to finish food and, at age 6 months, give cereal in the bottle. Differences were not observed for other outcomes, including maternal feeding beliefs or infant weight-for-length.</p>

<p><strong>CONCLUSIONS: </strong>A social media peer-group intervention was engaging and significantly impacted certain feeding behaviors in families with infants at high risk of obesity.</p>

10.1089/chi.2017.0042

Child Obes

28557558

Maintenance of Certification Part 4: From Trial to Tribute.

2017

2017 Mar 28

1097-6833

10.1016/j.jpeds.2017.03.016

J. Pediatr.

28363364