Human breast milk has long been considered “liquid gold” among clinicians treating premature babies in a newborn intensive care unit (NICU). Breast-fed “premiums” are, on average, healthier than those who are bottle-fed. Why that is true, however, has remained a mystery.
Newswise – New research from the University of Maryland School of Medicine’s (UMSOM) Institute for Genome Sciences (IGS), published online in June in the journal mBio, found that it’s not just the content of breast milk that makes the difference. It’s also the way the babies digest it.
The study, led by Bing Ma, PhD, Assistant Professor of Microbiology and Immunology at UMSOM and a researcher at IGS, discovered a strain of the Bifidobacterium breve bacterium or B. breve in the gut of breastfed babies who consumed higher amounts of breast milk. then got their counterparts. Those preemies had better nutrient absorption because they developed an intact intestinal wall a week after birth. B. breve was much less common in both bottle-fed and breastfed babies with ‘leaky gut’. Babies with leaky gut don’t develop a barrier to prevent bacteria and digested food from entering the bloodstream. For the first time, the team also found that the way B. breve metabolizes breast milk keeps breastfed babies healthier and allows them to gain weight by strengthening their underdeveloped gut barrier.
An immature or “leaky” gut can lead to necrotizing enterocolitis (NEC), the third leading cause of death in newborns in the United States and worldwide. In fact, NEC affects up to 10 percent of premature babies with a devastating death rate as high as 50 percent.
“Our discovery could lead to promising and practical clinical interventions to fortify infants’ guts and thereby increase the survival rates of the most vulnerable preterm infants,” said Dr. mom.
Bifidobacterium in the gut or microbiome has long been known to have health benefits. It includes a diverse range of species with very different traits. Some strains only occur in adults; some are usually in adolescence. One strain, Bifidobacterium infantis, has been observed primarily in term infants.
The researchers followed 113 premature babies born between 24 and 32 weeks of pregnancy. This study found Bifidobacterium breve (B. breve) only in preterm infants who had improved gut barrier function within one week of birth. dr. Ma and her colleagues found that Bifidobacterium breve is genetically equipped to digest nutrients within the cell membrane rather than the more typical external digestion process in which bacteria secrete digestive enzymes onto nutrients to break them down.
At the most basic level, the gut microbiome in these breastfed premiums metabolizes more B. breve carbohydrates differently than in the formula. The researchers say they hypothesize that this process of metabolism strengthens and matures the gut barrier more quickly, protecting vulnerable newborns from disease.
“We now know that it’s not just breast milk that helps premature babies develop their gut barrier faster,” said Dr. mom. “We will have to find the best way to prophylactically administer B. breve early in life, rather than relying on transmission from breast milk or even the mother’s gut or vaginal microbiota during the birth process. This is especially critical.” in preterm feeding premature.”
dr. Ma said more studies are needed to determine whether the B. breve comes from breast milk, the gut, the mother’s vagina, or even the environment.
E. Albert Reece, MD, PhD, MBA, Executive Vice President for Medical Affairs, University of Maryland, Baltimore, the John Z. and Akiko K. Bowers Distinguished Professor and Dean at UMSOM said, “This research could have a far-reaching global impact It could ultimately save thousands of premature babies from permanent disability or death due to an immature and permeable gut that lets in deadly bacteria.”
Institute for Genome Sciences authors include Dr. mom; Michael France, PhD, Post-Doc Fellow; Elias McComb, BS, research technician; Lindsay Rutt, MS, laboratory research manager; Pawal Gajer, PhD, research associate, microbiology and immunology; Li Fu, BS, laboratory research specialist; Hongqiu Yang, PhD, Microbiome Service Laboratory; Mike Humphrys, MS, director of microbiome service lab; Luke J. Tallon, BA, Executive Scientific Director, Maryland Genomics; Lisa Sadzewicz, PhD, Executive Director, Maryland Genomics Administration; and Jacques Ravel, PhD, Professor of Microbiology and Immunology, Associate Director, Genomics, and Interim Director, IGS.
Authors from other departments within the University of Maryland School of Medicine include Sripriya Sundararajan, MBBS, MD, associate professor of pediatrics and neonatal director of OB-MFM Relations; Gita Nadimpalli, MD, PhD, MPH, Graduate Research Assistant; Jose M. Lemme-Dumit, PhD, Post-Doc Fellow, Pediatrics; Elise Janofsky, Pediatrics; Lisa S. Roskes, MD, Pediatrics; Marcela F. Pasetti, PhD, professor of pediatrics, microbiology and immunology; and Rose M. Viscardi, MD, professor emeritus of pediatrics and medicine.
This study was supported in part by a Gerber Foundation 2018 award (project identifier 6361), the National Institutes of Health’s National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) (grant number R21DK123674) and the Institute for Clinical and Translational Research (ICTR) to the University of Maryland Accelerated Translational Incubator Pilot (ATIP) award.
The authors have no conflict of interest.
About the University of Maryland School of Medicine
Now in the third century, the University of Maryland School of Medicine was chartered in 1807 as the first public medical school in the United States. Today it remains one of the fastest growing, leading biomedical research companies in the world – with 46 academic departments, centers, institutes and programs, and a faculty of more than 3,000 physicians, scientists and allied health professionals, including members of the National Academy of Medicine and the National Academy of Sciences, and a distinguished two-time winner of the Albert E. Lasker Award in Medical Research. With an operating budget of more than $1.3 billion, the School of Medicine works closely with the University of Maryland Medical Center and Medical System to provide nearly 2 million patients with research-intensive, academic and clinically based care each year. The School of Medicine has nearly $600 million in outpatient funding, with most of its academic departments ranked highly among all medical schools in the nation in research funding. As one of seven professional schools that make up the University of Maryland, Baltimore campus, the School of Medicine has a total population of nearly 9,000 faculty and staff, including 2,500 students, interns, residents, and fellows. The combined School of Medicine and Medical System (“University of Maryland Medicine”) has an annual budget of more than $6 billion and an economic impact of nearly $20 billion on the state and local community. Ranked 8th among public medical schools in research productivity (according to the Association of American Medical Colleges profile), the School of Medicine is an innovator in translational medicine, with 606 active patents and 52 startup companies. In the latest US News & World Report ranking of the best medical schools, published in 2021, the UM School of Medicine ranks ninth out of 92 public medical schools in the US, and in the top 15 percent (#27) of all 192 public and private medical schools in the US. The School of Medicine works locally, nationally and globally, with research and treatment facilities in 36 countries around the world. Visit medschool.umaryland.edu
About the Institute of Genome Sciences: The Institute for Genome Sciences (IGS) at the University of Maryland School of Medicine has revolutionized genomic discoveries in medicine, agriculture, environmental science, and biodefense since its founding in 2007. IGS researchers explore areas of genomics and the microbiome to address health and disease, including treatments, cures and prevention. IGS researchers are also leading the development of the new field of microbial forensic science. IGS is a leading center for major biological initiatives currently underway, including the NIH-funded Human Microbiome Project (HMP) and the NIAID-sponsored Genomic Sequencing Center for Infectious Diseases (GSCID). Follow us on Twitter @GenomeScience.