To treat brain disorders like autism, scientists increasingly are targeting a different part of the body: the gut.
Imbalances in the gut microbiome ― the community of trillions of bacteria living in the digestive tract ― have been linked with mental and neurological disorders, including anxiety, depression, obsessive-compulsive disorder and Parkinson’s disease. Now, medical researchers are looking into ways of improving the health and diversity of the gut’s bacterial community in order to better treat these conditions.
New research suggests that the gut also may be an important site of intervention for autism spectrum disorders. Children with autism have been found to have a less diverse gut microbial community than neurotypical children, as well as lower levels of important strains of healthy bacteria. Scientists suspect that these differences play a role in behavioral symptoms of the disorder, like impaired social functioning.
“The role of microbiome in autism has received a lot of attention in the last couple of years,” Dr. Mathew Pletcher, vice president and head of genomic discovery at Autism Speaks, a research and advocacy organization, told The Huffington Post. “There is a lot of data supporting a link between behavior and digestive health.”
The preliminary study, conducted by researchers at Arizona State University and published in the journal Microbiome, showed that “microbiota transfer therapy” ― aka fecal transplants ― can improve the diversity of the gut microbiome, easing gastrointestinal and behavioral symptoms of austism.
While fecal transplants aren’t yet approved by the Food and Drug Administration, the early results are promising. Study co-author Dr. James Adams called findings “very compelling.”
“We completed a Phase 1 trial demonstrating safety and efficacy, but recommending such treatment and bringing it to market requires Phase 2 and Phase 3 trials,” Allen, a molecular biologist at the university, said in a statement. “We look forward to continuing research on this treatment method with a larger, placebo-controlled trial in the future.”
Targeting The Gut To Treat The Mind
For the study, the researchers recruited 18 boys and girls ages 7 to 16 who had been diagnosed with autism spectrum disorders. Each participant underwent a 10-week treatment program that included antibiotics, a bowel cleanse and daily fecal microbial transplants for two months.
Fecal transplants work by introducing the fecal matter of a healthy donor to the patients. The transplanted material contains around 1,000 different strains of gut bacteria, acting like an ultra-potent probiotic to help restore the health and diversity of the recipient’s intestinal flora.
At the end of the eight-week period, the participants showed a significant increase in the diversity of their gut microbiome, and increases in certain healthy bacteria strains thought to be deficient in children with autism. The healthy new microbes remained, even after the treatment period ended.
These changes in the microbiome seemed to lead to significant long-term symptom reduction. The participants showed an average of 80 percent improvement of gastrointestinal symptoms (which commonly occur with autism disorders). They also showed a 25 percent improvement in behavioral symptoms, including better sleeping habits and social skills.
”We were hoping for some improvement in autism symptoms and were pleased to see about a 25 percent improvement in only 10 weeks,” Dr. Rosa Krajmalnik-Brown, a biologist and study co-author, told HuffPost. “It was great to see that autism and GI symptoms improvement remained at least eight weeks after treatment stopped.”
New Hope For Treating Autism
The next step for the team is to conduct larger, placebo-controlled trials to confirm the efficacy of the treatment.
While fecal transplants aren’t quite ready for widespread public use, other methods of improving gut health could be of benefit to individuals with autism. A Baylor College of Medicine study published in June suggested that adding one particular strain of beneficial bacteria into the gut of individuals with autism could lessen symptoms.
Some parents have also have found success using dietary interventions to improve gut health. But so far, research is too limited to support a nutritional approach.
“Dietary changes such as increasing fiber intake, avoiding food allergens, or taking probiotics may have some limited benefit for some individuals, but in our opinion this treatment has a lot more promise,” said Krajmalnik-Brown. “Probiotics only contain one to 10 strains of bacteria that do not normally grow in the gut, whereas human microbiota contain more than 1,000 strains.”
But it’s early days yet. Pletcher, who was not involved in the research and reviewed the findings for HuffPost, warned of the study’s small sample size.
“I wouldn’t say these results are necessarily surprising, but with a study of this size ― we have to not over-interpret the results,” Pletcher said. “This is an encouraging first step in determining if this type of treatment will provide real benefit to the autism community.”
In other words, don’t take it upon yourself to try this one just yet. The researchers caution that improper techniques used without the guidance of a physician could result in serious harm.
“Families, do not try this at home,” said Krajmalnik-Brown. “Microbiota should be very carefully screened and the treatment should be done under medical supervision.”
CORRECTION: A previous version of this story referred to a study from the Baylor College of Medicine as being from Baylor College.