Researchers are exploring how psychedelic drugs like psilocybin may hold potential therapeutic effects in treating Alzheimer's disease.
More researchers are paying attention to the therapeutic benefits of psychedelics when it comes to treating mental illnesses like depression and addiction — and scientists are now looking at ways that the drugs may help combat Alzheimer’s disease.
Researchers are exploring that in-depth at Johns Hopkins University’s Center for Psychedelic & Consciousness Research, which launched in 2019 to study how psychedelics impact mood, behavior, brain health and cognition.
Psychedelics are hot right now. In 2019, the Food & Drug Administration (FDA) approved a drug called esketamine, which is chemically related to the psychedelic ketamine, as a treatment for depression. And the evidence that the class of drugs may have beneficial effects on the brain continues to grow.
How Do Psychedelics Work on the Brain?
Researchers are examining several different ways that psychedelics may impact the brain. What they’ve found is that when psychedelics take effect, there are physical changes in the brain all the way down to the cellular molecular level.
“If you’re looking at cells like neurons and expose them to these drugs, they create this kind of synapto-genesis,” Dr. Albert Garcia-Romeu, assistant professor of psychiatry and behavioral sciences at Johns Hopkins, said. “There are new outgrowths off the neuron, so that’s one thing they’ve found in studies in people and cells derived from people.”
Then there’s the impact of psychedelic drugs on something called the brain’s default mode network — a network of brain regions that’s involved in a person’s sense of self and “autobiography,” as well as moral reasoning and processing the emotions of other people.
The default mode network is also the basis for what Garcia refers to as the state when the mind is wandering and not necessarily focused on anything. Psychedelics come in and shake those connections up — resulting in a rearranged way of thinking.
“The connectivity [in the default mode network] is drastically altered when the drug is on board, and you have parts of the brain communicating in different ways when they normally would not,” Garcia said. “It’s been correlated with a decrease in depression.”
There also appears to be a decrease in amygdala connectivity, which is associated with emotional responses, and what Garcia refers to as “psycho-plastogenic effects,” which changes brain structure by creating new outgrowth of neurons.
But scientists still don’t fully understand how psychedelics are beneficial to the brain — and it’s perhaps what’s so exciting about the emerging research.
“It’s still a mystery,” Garcia said. “We’re basically in the very early stages of studying the neurobiology of these drugs.”
Can Psychedelics Improve Mood, Memory and Cognition in Alzheimer’s?
Currently, most of the solid scientific evidence behind psychedelics has focused on its potential to treat depression, addiction, anxiety disorders and other mental illnesses. But research is emerging to test the drugs’ ability to enhance mood, behavior or even memory in people with Alzheimer’s.
At Johns Hopkins, Garcia is currently working on a study focusing on a particular type of psychedelic known as psilocybin. Psilocybin is similar to LSD — both drugs work on what’s known as the serotonin 2A receptor in the brain — but it’s naturally-occurring, found in up to 200 different species of mushrooms. It’s known to cause a wide spectrum of visual and mental effects — from hallucinations to a changed sense of time, and heightened spiritual experiences.
The study at Johns Hopkins will look at whether moderate to high doses of psilocybin can work as a therapeutic agent in treating depression among people with mild cognitive impairment (MCI) or early onset Alzheimer’s.
“We’ve seen a lot of promising results using high doses [of psilocybin],” Garcia said. “We found these can have lasting therapeutic benefits including helping treat depression, anxiety and addictions.”
The researchers also aim to understand whether quality of life in general could improve among people who take the drug. It’s currently recruiting participants.
“Often when people get mild cognitive impairment or dementia that can adversely affect their mood,” he added. “We know that treating cancer patients with high dose psilocybin leads to improvements in mood and anxiety. We’re targeting that as our primary outcome [for people with Alzheimer’s].”
Though the evidence in humans is preliminary, there have been some promising animal studies that have shown improved learning and memory processes in rodents and monkeys given high doses of psilocybin. Whether that’s because psilocybin has been associated with anti-inflammatory effects (and inflammation has been linked to Alzheimer’s disease), or because influencing serotonin 2A receptors in the brain enhances cognition, is still being explored.