Psychedelic drug psilocybin may help increase the density of dendritic spines, small protrusions found on nerve cells that aid in the transmission of information between neurons, which might help treat depression, finds a new Yale research. Chronic stress and depression are known to decrease the number of these neuronal connections.
Psilocybin, a naturally occurring compound found in some mushrooms, has been analysed as a potential treatment for depression for years. But how long its beneficial results might last is still unclear. Most psilocybin directly affects the serotonin receptors of our brain. Previous experiments had shown that psilocybin, as well as anaesthetic ketamine, can decrease depression.
In the new research it was recognised that a single dose of psilocybin when given to mice prompted an immediate and long-lasting increase in connections between neurons.
“We not only saw a 10% increase in the number of neuronal connections, but also they were on average about 10% larger, so the connections were stronger as well,” said Alex Kwan, Yale’s, Associate Professor of Psychiatry and Neuroscience.
Using a laser-scanning microscope, Kwan and first author Ling-Xiao Shao, a postdoctoral associate in the Yale School of Medicine, imaged dendritic spines in high resolution and tracked them for multiple days in living mice.
They found an increase in the number of dendritic spines and in their size within 24 hours of administration of psilocybin. Also, mice subjected to stress showed behavioural improvements and increased neurotransmitter activity after being given psilocybin.
It may be the novel psychological effects of psilocybin itself that spur the growth of neuronal connections, Kwan said.”It was a real surprise to see such enduring changes from just one dose of psilocybin,” he said. “These new connections may be the structural changes the brain uses to store new experiences.”