Transformative New Probiotic Therapy Alleviates Autism-Like Behavior in Mice

Autism spectrum disorder (ASD) affects individuals across the U.S. and around the world. Now, though, scientists are investigating a potentially transformative new therapy for autism that could alleviate the symptoms associated with it. The new therapy has the potential to be life-changing for all those suffering from ASD.

Those that possess ASD often exhibit characteristic behaviors that include repetitive actions, decreased social interactions and impaired communication. Strangely enough, many individuals with ASD also suffer from gastrointestinal issues (GI), such as abdominal cramps and constipation. Inspired by this fact, the researchers decided to take a closer look at the microbiota of the gut, or the gut bacteria.

"Traditional research has studied autism as a genetic disorder and a disorder of the brain, but our work shows that gut bacteria may contribute to ASD-like symptoms in ways that were previously unappreciated," said Sarkis K. Mazmanian, one of the researchers, in a news release. "Gut physiology appears to have effects on what are currently presumed to be brain functions."

In order to study how gut microbiota might impact the brain, the researchers examined mice with the core behavioral symptoms associated with autism. After studying these mice, the scientists found that they also exhibited GI abnormalities. In particular, the GI tracts of the autistic-like mice were "leaky," which means that they allow material to pass through the intestinal wall and into the bloodstream. Known as intestinal permeability, this characteristic has been reported in some autistic individuals.

The researchers then treated the mice with Bacteroides fragilis, a bacterium that has been used as an experimental probiotic therapy in animal models of GI disorders. This, in turn corrected the leaky gut. Not only that, but the treated mice had changed behaviors; in particular, they were more likely to communicate with other mice, had reduced anxiety and were less likely to engage in repetitive behavior.

"This probiotic treatment is postnatal, which means that the mother has already experienced the immune challenge and, as a result, the growing fetuses have already started down a different development path," said Paul Patterson, one of the researchers, in a news release. "In this study, we can provide a treatment after the offspring have been born that can help improve certain behaviors. I think that's a powerful part of the story."

Currently, the scientists are planning a trial to test the probiotic treatment on the behavioral symptoms of human autism. Yet quite a bit of work still remains to develop this effective and reliable probiotic therapy. Yet these findings spell hope for the future and for future therapies.

The findings are published in the journal Cell.