A new study from the University of Alberta shows that there is an
additional and potentially treatable reason why children born to mothers with
asthma often develop the disease later on.
Familial risk for asthma tends to be passed from mothers to babies, scientists
say, and this may not be the result of genetics alone, but a combination of
factors such as exposure to microbes found in the baby’s digestive tract. The
research team found that Caucasian boys born to moms with asthma, who are
typically at the highest risk of developing asthma in early childhood, were
also one-third more likely to have a gut microbiome with specific
characteristics at three to four months of age.
The authors found a significant reduction in a family of microbes called
Lactobacillus in Caucasian boys born to women with asthma, and this was
especially noticeable if the mother was allergic or overweight. These findings
provide the first evidence that maternal asthma during pregnancy may be
associated with changes in the baby’s gut microbiome , the researchers say.
This finding, backed up by several studies, could eventually lead to a
preventive approach that involves altering the gut microbiome in infants to
reduce their risk of developing asthma. Along with this, scientists are
concerned that parents are undertaking probiotic treatments for their children
too early to solve this problem.
More than a thousand mothers and their children have been studied. The team
became interested in studying the relationship between asthma and the gut
microbiome , based on the fact that maternal asthma affects the birth weight of
a child depending on gender.
It was already known that a male fetus would have a lower birth weight if the
mother had asthma, so it was decided to investigate further, given the
differences already found based on the sex of the child. The study also showed
that maternal asthma affected the intestinal bacterial composition of female
infants, but in a different way. Girls had more bacteria in the Bacteroidaceae
family , which are important in maintaining the mucus barrier that protects
intestinal cells from damage by harmful substances. The authors suggested that
this may protect girls from developing asthma at an early age. On the other
hand, changes in the composition of the bacteria characteristic of infant girls
may increase the risk of developing asthma during puberty.
Given new research linking the gut microbiome to asthma and allergies, the new
findings may ultimately help prevent asthma in children.