A new study found that repurposing drugs, such as diarrhoea medication, could treat autism symptoms.
Medication that treats core autism spectrum disorder (ASD) symptoms are not currently available. To combat this, researchers from the University of Oslo analysed existing drugs that could be repurposed to target core autism symptoms, such as diarrhoea medication. The researchers employed a computer model that showed how proteins involved in autism interacted.
“There are no medications currently approved for the treatment of social communication deficits, the main symptom in ASD,” said Dr Elise Koch of the University of Oslo, lead author of the study. “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.”
The researchers published their findings in Frontiers in Pharmacology.
Repurposing diarrhoea medication to target symptoms
The researchers focussed on drug repurposing to find a solution for treating common autism symptoms. Drug repurposing explores how existing drugs interact and work as potential treatments for different conditions. This approach is highly beneficial including:
- Extensive knowledge typically exists of the drug;
- Information regarding their safety, side effects, and the biological molecules they interact with within the body, and;
- New drug development can take many years – this method reduces this time.
To identify new treatments for autism, the researchers used a computer-based protein interaction network. These networks encompass proteins and the complex interactions between them. It is important to account for the complex interactions when studying biological systems, as affecting one protein can often have knock-on effects elsewhere.
The researchers designed a protein interaction network that included proteins associated with autism. Through this investigation, the team found several drugs, including a diarrhoea medication, that could be useful.
Loperamide, a diarrhoea medication, looked most promising. The research team developed a hypothesis which constructively outlines why this medication could work for autism symptoms.
Why does loperamide work for autism?
Loperamide binds to and activates a protein called the μ-opioid receptor, which is normally affected by opioid drugs, such as morphine. This protein also affects social behaviour surprisingly.
Previous studies have found that genetically engineered mice that lack the μ-opioid receptor demonstrated social deficits similar to those seen in autism. Surprisingly, the drugs that activate the μ-opioid receptor helped to restore social behaviours.
These results highlighted the prospect that diarrhoea medication or other drugs that target the reception could treat the social symptoms seen in autism. Further work will be required to test this hypothesis; however, the study highlights the importance of drug repurposing in finding new treatments.