The gut microbiome’s role in overall health has become a growing area of scientific interest, with research revealing its impact on everything from immune response to mental health.
Publishings in The Journal of Immunology
Study used animal models to explore how maternal gut microbiota may shape the neurological development of offspring. Researchers at the University of Virginia School of Medicine found that the mother’s microbiome could have a greater effect on the child’s risk of developing autism than the child’s own gut bacteria.
“The microbiome can shape the developing brain in multiple ways,” said lead researcher John Lukens, PhD. “It plays a critical role in calibrating the immune system’s response to infections, injuries, or stress during early development.”
A central player in this process appears to be interleukin-17a (IL-17a), a molecule produced by the immune system. IL-17a is already associated with autoimmune conditions like multiple sclerosis, psoriasis, and rheumatoid arthritis—and is also known to help the body fight infections, particularly fungal ones. Crucially, it has also been shown to influence brain development in the womb.
Experiments on lab mice
To investigate IL-17a’s role in autism, researchers conducted experiments on lab mice. They used two different groups of female mice. One with a gut microbiome known to trigger an inflammatory IL-17a response and another without such predisposition. When IL-17a was artificially suppressed in both groups during pregnancy, all offspring showed typical neurodevelopmental behavior.
However, when allowed to proceed naturally, the offspring of the first group—whose microbiota was prone to inflammation—exhibited behaviors resembling autism, including changes in social interaction and repetitive actions.
To confirm the microbiota’s role, the researchers performed a fecal transplant from the first group of mice into the second group. Effectively transferring the inflammatory-prone microbiome. As predicted, the pups from the second group also developed autism-like behaviors. Underscoring the influence of maternal gut bacteria on neurodevelopment.
Although the study was conducted on animals and more research is needed before drawing conclusions. The findings open a compelling avenue for future autism research. They suggest that maternal gut health may play a significant role in shaping a child’s neurological development.
The next step, according to Lukens, is to identify which specific elements of the maternal microbiome are linked to autism. Also whether similar patterns exist in humans. “IL-17a might just be one piece of a much larger puzzle,” he said. “There are many other immune molecules we need to explore.”
As research progresses, this study adds to growing evidence that maternal microbiota may be a critical factor in autism risk, highlighting the importance of gut health during pregnancy.
