A compelling study has utilized a new kind of computer modeling to investigate how pre-existing drugs could be repurposed to treat autism spectrum disorder (ASD). Among the findings was a curious discovery indicating a common anti-diarrhea drug could hypothetically improve ASD symptoms.
“There are no medications currently approved for the treatment of social communication deficits, the main symptom in ASD,” explained lead author on the study Elise Koch, from the University of Oslo. “However, most adults and about half of children and adolescents with ASD are treated with antipsychotic drugs, which have serious side effects or lack efficacy in ASD.”
To explore potential new treatments for ASD the researchers used a type of computer modeling that simulates complex protein interactions. A network modeling proteins associated with ASD was constructed and the influence of pre-existing drugs on that network was then modeled, with the results pointing to several molecules that could counteract the processes underlying ASD.
Some of the molecules that were flagged by the modeling have previously been identified as potentially relevant in the development of ASD. The female sex hormone progesterone and synthetic progestin counterpart drospirenone, for example, were suggested as relevant in ASD and the researchers pointed to prior research suggesting progesterone has been positively associated with cognitive performance in healthy subjects.
However, the most significant finding in the study was the discovery of a common anti-diarrheal drug potentially playing a role as a treatment for ASD symptoms. Called loperamide, this over-the-counter medicine has been widely used safely for nearly 50 years.
Loperamide’s mechanism of action offers intriguing clues to potential future ASD therapies. The drug is essentially an opiate, targeting μ-opioid receptor proteins. But since loperamide cannot cross the blood-brain barrier, it only works on μ-opioid receptor activity in the gut.
In the study, published in Frontiers in Pharmacology, the researchers note prior experiments breeding μ-opioid-receptor-deficient mice led to the animals displaying behavioral deficits that resembled ASD. So it’s plausible that targeting this mechanism could be a way to treat ASD symptoms.
“Thus, the identification of loperamide as a drug repurposing candidate for ASD is consistent with its potential to modulate social behavior in ASD,” the researchers note in the study. “In addition, it may have favorable gastrointestinal effects in individuals with ASD, as gastrointestinal symptoms are common in ASD.”
The study was published in Frontiers in Pharmacology.
Source: Frontiers