Study Reports Probiotic Therapy Relieved Symptoms of Autism in Mice
In a new study, researchers from the California Institute Technology (Caltech) investigated a different approach in treating autism spectrum disorders (ASD). ASD is a group of developmental disorders that are characterized by varying degrees of common symptoms, which include impaired communication, repetitive actions, and reduced social interactions. ASD has also been linked to gastrointestinal issues, which prompted the researchers to focus on gut microbiota, which is the bacteria community living inside the GI tract of humans. The researchers discovered in mice models, at least, that probiotic therapy could relieve some of the autism-related behaviors.
"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 Professor of Biology Sarkis K. Mazmanian according to a press release. "Gut physiology appears to have effects on what are currently presumed to be brain functions."
The research team used a specific mouse model of autism that was created by Paul H. Patterson, the Anne P. and Benjamin F. Biaggini Professor of Biological Sciences, at the Caltech laboratory. Patterson created the model by infecting the mice with a severe viral infection, which was similar to the viral infections in humans. Viral infections had been tied to raising a pregnant woman's risk of giving birth to an autistic child. The mice then gave birth to offspring with core autistic symptoms.
The researchers then gave the autistic mice Bacteroides fragilis, which is a bacterium used to treat GI disorders in animal models. The researchers found that the treated mice experienced changes in their behavior. The mice became more willing to communicate with other mice. The treated mice also had reduced anxiety and performed repetitive actions, such as digging less often.
"The B. fragilis treatment alleviates GI problems in the mouse model and also improves some of the main behavioral symptoms," senior research fellow at Caltech and first author of the study, Elaine Hsiao said. "This suggests that GI problems could contribute to particular symptoms in neurodevelopmental disorders."
"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 developmental path," Patterson added. "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."
The study was published in Cell.