The risk of autism in children appears to be directly linked to the health of the mother's gut during pregnancy, suggesting that a customized formula of probiotics taken by an expectant mother, or in some cases simply adjusting her diet, could play an important role in preventing the developmental disorder, according to a groundbreaking new study by scientists at the University of Virginia.
The research focused on what scientists call the microbiome, which is the highly complex ecosystem of single-cell organisms, primarily bacteria, that inhabit every human digestive tract. Anywhere from 10 trillion to 100 trillion cells typically inhabit the human gut, according to the National Institute of Health, and science is only beginning to understand the importance of this system, which the NIH calls the "second brain," because the microbiome is known to communicate with the central nervous system and human immune system — leading to a direct connection between gut health and the overall health of the body and even the brain.
Though exactly how the system of gut bacteria sends signals to the brain and body remains largely mysterious, the University of Virginia study could help define how gut health influences development of the brain. Scientists have long studied the micribiome health of children on the autism spectrum, because symptoms of the disorder are often accompanied by gastrointestinal distress, according to a report on the Virginia study by The Roanoke Times.
The study published this month in The Journal of Immunology found a link between gut inflammation during pregnancy and the development of autism-like neurological disorders. The researchers say that they found two possible ways to treat the inflammation and lower the risk of autism in the developing fetus — either by adjusting the mother's diet and treating her with a combination of probiotics, or by blocking a specific inflammatory molecule known as interleukin-17a.
But blocking the molecule would be a more risky and complicated form of treatment.
"I think the next big step would be to identify features of the microbiome in pregnant mothers that correlate with autism risk," lead researcher John Lukens of the University of Virginia Department of Neuroscience said, as quoted by Science Daily. "I think the really important thing is to figure out what kind of things can be used to modulate the microbiome in the mother as effectively and safely as we can."
But Lukens cautioned moms who may experience gut inflammation during pregnancy not to panic.
"It's important to mention, just because you have an inflammatory reaction during pregnancy doesn't mean you are going to have a child with autism or another neurodevelopmental disorder," the neuroscientist told The Roanoke Times.
"Going forward, there is still a lot that needs to be done," Lukens added. "If we were able to identify microbes in the human microbiome that were linked to having a higher risk of having an autistic child, that would be a major step forward. Then you can imagine ways, pretty safe ways, to lower that risk, whether it's taking probiotics or changing your diet."