Antidepressants are one of the most frequently prescribed medications in the US. While selective serotonin reuptake inhibitors (SSRIs) are among the most commonly prescribed antidepressants, their underlying mechanisms of action are unclear.
In the current study, researchers investigated how SSRIs affect membrane trafficking- the ability of cells to transport material in and out of their environment. To do so, they tested SSRIs at similar concentrations to those found in the blood of patients treated for depression on various types of cells grown in petri dishes. Almost all of the SSRIs observed affected membrane trafficking.
The researchers further found that an injection of antidepressant fluvoxamine enabled a fluorescent compound that normally would stay outside of the brain to cross the blood-brain barrier and accumulate in the brain.
"Given how little is known about the wider effects of antidepressants, we wanted to understand more about how these drugs affect the cells in our brains and bodies. What we found was that most antidepressants regulate the same key biological process across many tissues, which likely has little to do with their effect on depression," said Dr. Oleg Glebov, Lecturer in Old Age Psychiatry and King's College London, in a press release.
He added that the data suggests a single antidepressant dose may be sufficient to 'open up' the blood-brain barrier for the delivery of other drugs.
"We hope that this finding may help improve clinical efficacy and drive down the treatment cost for new drugs against dementia, which currently are unavailable to millions of people who need them. Besides that, we are excited to explore whether antidepressants may help deliver drugs into other hard-to-reach corners of the body," he added.
Further research with collaboration across multiple disciplines is needed to understand how exactly SSRIs control membrane trafficking. Further study is also required to know whether SSRI's could be used for drug delivery in humans.
Sources: Neuroscience News, Molecular Psychiatry