A single dose of the drug rapamycin reversed "autism-like brain changes" in adult mice within hours, according to a new study from UCLA Health. The research suggests that some autism-related brain changes may still be treatable in adulthood, but the effects are temporary and the drug is not recommended for human use.
Study details
Researchers exposed pregnant mice to mild inflammation, and their offspring developed lasting autism-like brain and behaviour changes, including brain overactivity, seizure risk, sensory sensitivity, repetitive behaviours and abnormal brain functional network organization. The study published in the journal Nature Communications found that a single dose of rapamycin rapidly improved these changes within about two hours.
UCLA Health said: "The findings suggest that some autism-related brain changes may still be treatable in adulthood, pointing to possible therapeutic approaches that target the underlying pathway rather than only symptoms. The effects of rapamycin are temporary, and repeated dosing loses efficacy, making rapamycin, itself, an unlikely candidate as a broadly-used treatment."
Implications and cautions
The study authors stressed that they "do not identify rapamycin as a viable treatment for these symptoms in humans given its temporary effects and potential for toxicity from repeated doses." Instead, the drug’s effects "revealed new therapeutic targets for the development of future treatments."
Dr Harley Kornblum, the study's senior author, said: "It suggests the adult brain may be more adaptable than we assumed, even when the underlying structural changes from early development are still there. This points us toward the brain's functional circuitry, not just its physical structure, as a target for future treatment approaches."
Dr Janel Le Belle, an associate professor in the UCLA Department of Neurosurgery, added: "These results reframe how autism-associated symptoms might be treated. If the adult brain remains capable of functional normalisation, then some features of autism may be successfully addressed without needing to correct underlying structural differences."
What is rapamycin?
Rapamycin is licensed and used in the UK, primarily to prevent organ rejection in transplant patients and to treat specific lung diseases. Related drugs are used for some targeted cancer treatments. It is also being researched for longevity and chronic illnesses like ME.
Causes of autism
The National Autistic Society says evidence suggests autism may be genetic. It states: "Scientists have been attempting to identify which genes might be implicated in autism for some years. Autism is likely to have multiple genes responsible rather than a single gene. However, it is not caused by emotional deprivation or the way a person has been brought up. There is no link between autism and vaccines."
