Psychedelics could relieve depression without causing hallucinations
New study forges a different path for research
Millions of Americans experience symptoms of depression, and the number of people seeking care continues to grow. In recent years, psychedelics have become a hot topic due to their antidepressant effects, but remain a subject of controversy among scientists.
Psychedelics research has been labeled “treacherous” due to their hallucinogenic nature and the risk of psychosis in some patients. However, researchers at the University of Helsinki in Finland may have found a way around this effect.
In a recent study published in Nature, researchers were able to produce antidepressant effects in mice by targeting a different receptor than previously studied.
Most psychedelics research focuses on the serotonin receptor, the brain’s intermediary for hallucinations. This time, investigators targeted the TrkB receptor, the part of the brain responsible for neuroplasticity.
“All antidepressants induce plasticity through [TrkB],” said study author Rafael Moliner in a Twitter thread. The TrkB plasticity effect is what makes us feel better.
In the new study, Moliner and his team gave mice LSD in combination with a blocker for the serotonin receptor. These mice displayed a reduction in depressive behaviors without the usual hallucinations.
Since the beginning of COVID-19, the number of people who experience depressive symptoms has grown from 193 million people worldwide to 246 million. According to the WHO, a depressive episode can affect all aspects of a person’s functioning and lead to self-harm. And while telehealth and access to therapies are on the rise, many people who experience depressive episodes still don’t — or are not able to — seek help. And even for those who do, depression research has yet to find the magic bullet.
“The ways we treat depression are remarkably limited,” said Charles Raison, Professor of Psychiatry at University of Wisconsin, in a recent interview. Most of the depression drugs available were discovered two generations ago. Scientists like Raison say the entire field is due for an update.
“There’s a huge unmet treatment need,” he said.
TrkB may be an essential part of the equation in targeting depression as well as other mood disorders in the brain. Moliner’s team observed that LSD binds to TrkB at a rate 1000 times stronger than antidepressants. In addition, the drug led to significantly increased neural connections in mice.
Critics of psychedelic research say that studies like this using mice can’t be presumed to translate perfectly to humans. However, the group’s findings draw attention to an overlooked part of the brain that may hold more answers for treating depression in the future.
In an interview with Science, Gabriel Jacobs, a clinical pharmacologist, said that the study’s results will prompt more interest in finding drugs that target TrkB.
Moliner remains hopeful, saying their findings open up “a promising avenue for safer and more effective therapeutics that could reach a wider population of patients.”
