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Today’s lead story is written by journalist Noah Daly about the latest study looking at psilocybin and Parkinson’s disease. Researchers at UCSF and Columbia University found that psilocybin may do more for physical illnesses than solely just ease symptoms of mental ones. You can find that story immediately below!

If you keep scrolling, you’ll find stories about the playlists used in psychedelic therapy, the efficacy of ketamine therapy on depression for DB’s co-founder, and a profile on Ayana Iyi, one of the most legendary women in the mushroom ceremony world.

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In a small study of people with Parkinson’s and depression, inflammation dropped after just two psilocybin sessions and remained lower at the 30-day mark.

By Noah Daly

For years, researchers have explored how psychedelics can address inflammation. When psychedelics enter the brain, they clump onto serotonin receptors, which has made them interesting candidates for treating mental health conditions. But what about their efficacy in treating physical illnesses? Researchers at the University of California, San Francisco, and Columbia University now have a reason to believe that psilocybin may help. In a small study of people with Parkinson’s disease and depression, two doses of psilocybin significantly lowered markers of inflammation in the blood, and the effect held a month after the final dose.

Published in the journal JAMA Psychiatry on Wednesday, Oct. 21, the study set out to show whether psilocybin could be a safe and effective therapy for people diagnosed with Parkinson's disease who also have depression. Along the way, the researchers collected what they say is the first human data on how psychedelics impact inflammation in people with neurodegenerative disease.

Inflammation is the body’s response to physical damage, infections, and foreign objects invading the body, among other things. It's a cascade of processes that helps the immune system fight off threats and heal the body, but when there’s no threat to fight, inflammation can be deadly. For example, a runaway immune system response, like sepsis, can cause widespread inflammation and contribute to organ failure. Severe allergic reactions can also trigger life-threatening complications, like airway swelling and dangerous drops in blood pressure. Inflammation can be harmful even when a real threat remains, as seen when the body produces an excessive response to infection. It can also persist after the original trigger is gone.

We are still not sure what triggers Parkinson's. It is a neurodegenerative disorder that attacks the nervous system. It's characterized by the progressive loss of motor control and is commonly associated with mood disorders. Several types of inflammation in the brain and in the immune system contribute to the progression of Parkinson's, and it's believed the gradual decay of neurons producing dopamine also play a key role in the disease, which affects more than 10 million people worldwide, according to the Parkinson's Foundation.

Neurodegenerative disorders like this usually exclude someone from psychedelic therapy, but the researchers’ earlier trial showed that psilocybin was safe for people with Parkinson's and may have eased their symptoms. In this new analysis, the researchers measured five molecules in the blood that signal inflammation. Four are proteins immune cells use to communicate with one another, and the fifth is a protein the liver produces when inflammation flares, which doctors commonly test for. Participants first received 10 milligrams of the drug and, approximately two weeks later, 25 milligrams.

By analyzing blood samples from the participants, all of whom had both Parkinson's disease and mood dysfunction, the researchers tracked how levels of those five molecules changed before and after treatment.

The scientists found that inflammation decreased significantly after the participants received the drug, and an overall measure of inflammation remained lower a month after the final dose. They also tracked two markers of mitochondrial stress. One of them, GDF-15 — a protein that cells release into the blood when their mitochondria are strained, which tends to run high in people with Parkinson’s — dropped the day after each dose but was no longer significantly lower by the 30-day mark. While the researchers noted that the study’s small cohort of participants knew they were receiving psilocybin, and that there was no control group, they found an important proof-of-concept, according to Parker Kelley, a research scientist in the Mitochondrial PsychoBiology group at Columbia University who was a co-first author on the new paper.

“It’s a potential jumping-off point for a lot more research in this area,” Kelley told NPR. “That may apply not only to Parkinson’s, but also neuropsychiatric disorders like depression and anxiety, and even cardio-metabolic and inflammatory disorders.”

Future research will need to follow the thread of researchers like Charles Nichols, who's been studying the anti-inflammatory effects of psychedelics at LSU Health New Orleans for the past several decades. In 2008, Nichols and his colleagues found that several psychedelics reduced inflammation in lab-grown cells. Since then, they've studied the effects of psychedelics on arthritis and heart disease among others in animal models, but the new data from UCSF and Columbia brings much-needed evidence that this may translate to treating inflammation in people, too.

Before psilocybin can be considered an anti-inflammatory medicine that is ready to use in humans, researchers still need to establish whether the drug directly reduces inflammatory markers, rather than changes in the things that move those markers, like stress or other factors. Repeated blood samples would also help identify when changes begin and how long they last.

Scientists have already been able to show that some psychedelics have powerful anti-inflammatory properties. An open-label study at Johns Hopkins published this past February suggests that people living with post-treatment Lyme disease can find relief from symptoms related to inflammation. Early clinical studies on classical psychedelics — primarily psilocybin and LSD — suggest they can significantly reduce cluster headache attack frequency and break active cycles.

While more research is needed, findings in this new paper show that psilocybin’s anti-inflammatory effects may extend to people with Parkinson’s.

This article was produced in partnership with Psychedelic State(s) of America – a nonprofit-sponsored news organization dedicated to rigorous independent psychedelic journalism. Learn more about PSA’s Media Partnerships Program and the PSA Media Fund here.