Canadian neuroscientists may have identified a new approach for depression treatment.
Researchers at the Centre for Addiction and Mental Health (CAMH) believe a treatment strategy that uses a protein peptide to block receptors of the key neurotransmitter dopamine may be a better method than using medications to block serotonin or norepinephrine transporters.
Scientists hope the new approach will be helpful for more people and have fewer side effects.
Worldwide, depression affects one in ten individuals at some time in their lives and is a leading cause of disability.
The study published in this month’s Nature Medicine found that coupling between two dopamine receptors was significantly elevated in the brains of people who had been diagnosed with major depression.
“We identified a potential therapeutic target for development of novel anti-depressants,” said Dr. Fang Liu of CAMH.
Working from this discovery, researchers sought to find a way to disrupt coupling between the two receptors in hopes that it would have an antidepressant effect.
Using an autopsied brain study, Liu and her team initially found that coupling between two dopamine receptors was significantly elevated in the brains of people who had been diagnosed with major depression.
They started by analyzing a specific dopamine signaling mechanism, the D1 and D2 receptor complex, to identify the sites where the two receptors bind together.
With this information, they were able to generate a protein peptide to disrupt the binding of the two receptors. The peptide was then tested in animals to compare the effects with existing antidepressant medications.
“After we administered the peptide, we saw a marked improvement in depression-related behaviors. The improvement seen in the peptide group was equivalent to the improvement on traditional antidepressant medication,” Liu said.
This peptide is an entirely new approach to treating depression, which has previously relied on medications that block neurotransmitters. These conventional antidepressant medications don’t work for all patients, and can cause various side effects.
“We are hopeful that our research will lead to new options for treatment that might have reduced side effects for patients with depression,” Liu stated.