Gut microbe link may lead to prevention of asthma

Family risk for asthma — typically passed from moms to babies — may not be a result of genetics alone: it may also involve the microbes found in a baby’s digestive tract, shows University of Alberta research that could one day lead to prevention.

Caucasian baby boys born to pregnant moms with asthma, typically at highest risk for developing asthma in early childhood, were also one-third as likely to have a gut microbiome with specific characteristics at three to four months of age, found the research team led by Anita Kozyrskyj, U of A microbiome epidemiologist and AllerGen investigator.

“We saw a significant reduction in the family of microbes called Lactobacillus in Caucasian baby boys born to pregnant women who had asthma, and this was especially evident if the asthmatic mother had allergies or was overweight,” said Kozyrskyj, a leading researcher on the gut microbiome.

“Our discovery, with more research, could eventually lead to a preventative approach involving modifying the gut microbiome in infants to reduce the risk.”

The team’s research involved over 1,000 mothers and their infants participating in AllerGen’s study, a national population-based birth cohort. “Given emerging research linking the gut microbiome to asthma and allergies, we are excited that our results have uncovered a new finding that may eventually contribute to the prevention of childhood asthma.”

Maternal asthma affects infant birth weight in a sex-specific manner. “The Caucasian male fetus is more likely to have a lower birth weight in response to maternal asthma, so we knew there were already sex-based differences occurring and we decided to study them further,” said Kozyrskyj.

The study also found that maternal asthma had an impact on the gut bacterial profile of baby girls, but in a different way.

“Baby girls were more likely to have higher amounts of bacteria in the Bacteroidaceae family, which are important for maintaining the mucus barrier that protects gut cells from damage by harmful substances,” said Kozyrskyj.

The study, funded by Canadian Institutes of Health Research and AllerGen, has been published in European Respiratory Journal.