05 May Hormones in Breast Milk Shape Infant’s Microbiome
MedicalResearch.com Interview with:
Jacob (Jed) E. Friedman, Professor, Ph.D.
Department of Pediatrics, Biochemistry & Molecular Genetics
Director, NIH Center for Human Nutrition Research Metabolism Core Laboratory
University of Colorado Anschutz
MedicalResearch.com: What is the background for this study? What are the main findings?
Response: Scientists have long established that children who are breastfed are less likely to be obese as adults, though they have yet to identify precisely how breastfeeding protects children against obesity. One likely reason is that children who are breastfed have different bacteria in their intestines than those who are formula fed.
The study, published Monday in the American Journal of Clinical Nutrition examines the role of human milk hormones in the development of infants’ microbiome, a bacterial ecosystem in the digestive system that contributes to multiple facets of health.
“This is the first study of its kind to suggest that hormones in human milk may play an important role in shaping a healthy infant microbiome,” said Bridget Young, co-first author and assistant professor of pediatric nutrition at CU Anschutz. “We’ve known for a long time that breast milk contributes to infant intestinal maturation and healthy growth. This study suggests that hormones in milk may be partly responsible for this positive impact through interactions with the infant’s developing microbiome.”
Researchers found that levels of insulin and leptin in the breastmilk were positively associated with greater microbial diversity and families of bacteria in the infants’ stool. Insulin and leptin were associated with bacterial functions that help the intestine develop as a barrier against harmful toxins, which help prevent intestinal inflammation. By promoting a stronger intestinal barrier early in life, these hormones also may protect children from chronic low-grade inflammation, which can lead to a host of additional digestive problems and diseases.
In addition, researchers found significant differences in the intestinal microbiome of breastfed infants who are born to mothers with obesity compared to those born to mothers of normal weight. Infants born to mothers with obesity showed a significant reduction in gammaproteobacteria, a pioneer species that aids in normal intestinal development and microbiome maturation.
Gammaproteobacteria have been shown in mice and newborn infants to cause a healthy amount inflammation in their intestines, protecting them from inflammatory and autoimmune disorders later in life. The 2-week-old infants born to obese mothers in this study had a reduced number of gammaproteobacteria in the infant gut microbiome.
MedicalResearch.com: What should readers take away from your report?
Response: Young and Lemas hypothesize that human milk hormones affect the microbiome by binding to specific receptors in the infants’ intestines. These hormones may stimulate the body to produce proteins, called anti-microbial peptides, which kill off certain types of bad bacteria and may stimulate infant intestinal cells to secrete molecules that allow good bacteria to flourish.
MedicalResearch.com: What recommendations do you have for future research as a result of this study?
Response: “These early results will help lay the groundwork for us to understand what factors help make up a healthier immune system in infants born to obese mothers over the first year of life,” said Jed Friedman, corresponding author and professor of pediatrics at CU Anschutz. “What happens if you restore these bacteria in the infant born to an obese mother remains an open question.”
MedicalResearch.com: Thank you for your contribution to the MedicalResearch.com community.
DJ Lemas, BE Young, PR Baker II, AC Tomczik, TK Soderborg, TL Hernandez, BA de la Houssaye, CE Robertson, MC Rudolph, D Ir, ZW Patinkin, NF Krebs, SA Santorico, T Weir, LA Barbour, DN Frank, and JE Friedman
Alterations in human milk leptin and insulin are associated with early changes in the infant intestinal microbiome
American Journal Clinical Nutrition May 2016
Note: Content is Not intended as medical advice. Please consult your health care provider regarding your specific medical condition and questions.