In a nutshell, serotonin is an amino acid that plays a key role in regulating mood.
A number of studies have found that antidepressants work by increasing serotonin levels, which in turn triggers a feeling of well-being.
But these studies have been small and controlled.
So now, researchers from the University of British Columbia and the University at Buffalo have developed a novel drug that blocks serotonin levels and is also effective at lowering mood, and they have also found that it works in a similar way to traditional antidepressants.
In other words, it may have a role in treating depression in a way that traditional antidepressants don’t.
And it does.
“Serotonin is a key chemical in mood regulation, and in the long term we may find that we can have a therapeutic effect with serotonin-blockers,” says lead author Michael Stapleton, a professor in the department of psychology at UBC.
“The way it works is, you get this neurotransmitter, serotonin, that is produced in the brain when people have depression.
You have this receptor, serotonin transporter, that attaches to this receptor and activates it.
And that activates other receptor proteins that make it more difficult for serotonin to get to the brain.”
Stapton says his team was able to find a receptor that has been shown to have a high affinity for serotonin, and this has given the researchers a new route to finding new antidepressants that block serotonin and not only reduce its levels.
StapTON says the drug has already been tested in a pilot study in humans, but he hopes to test it in larger trials in the coming months.
Stavrova’s team will also be looking at whether the drug is able to prevent serotonin depletion in the body.
Stacie Bussman, a PhD candidate at the University’s Department of Neuroscience, says that’s a big challenge for her lab.
“We don’t know what the mechanism is for the antidepressant action, and we’re still trying to figure out how it works,” she says.
“So this could be the next step for us to try to understand the mechanism of action and see if it works.”
Stacies team is working with researchers at McGill University and the National Institute on Drug Abuse to find out what makes serotonin different from other serotonin receptors.
Bussmann says she expects the next phase of research will look at whether serotonin can help reduce anxiety and depression.
And the researchers also want to determine if the drug could work in humans as well as animals.
They plan to continue to work on developing the drug for several years and will eventually use it to treat people with major depressive disorder.
They also plan to look at the effects of other drugs on serotonin and to see if the compound could help people with anxiety disorders, schizophrenia, and autism spectrum disorders.
But Bussmans team will most likely start small, with just a handful of people taking the drug at a time.
“At that point, we will be looking for safety, but we will also want some early evidence of efficacy, and so we will begin that phase very early,” she adds.
The study was published in the journal Science Translational Medicine.