The idea may seem crazy: ingesting psilocybin, the active ingredient in hallucinogenic mushrooms, before starting chemotherapy, not to relax but to protect oneself from one of its most common and harmful side effects.
However, this is a possibility that was very seriously raised on Thursday by researchers. in a study published in the prestigious journal Science.
Conducted primarily on mice and some human tissue, their experiments focus on a complication known as "« peripheral neuropathy«", which affects millions of patients worldwide.
This nerve damage affects "« about three-quarters of patients »"under chemotherapy," explains Patrick Dougherty, co-author of the study, during a call with the press.
It is commonly translated as "« numbness and tingling »"unpleasant or even painful, but can also, in the case of..."« about a third » affected patients, leading to a « continuous and persistent burning pain«" explains this pain specialist at the University of Texas MD Anderson Cancer Center.
Symptoms may also include walking difficulties and other debilitating complications that can persist long after chemotherapy and have a lasting impact on the patient's life.
Beyond quality of life, this complication also weighs on patients' chances of survival, as oncologists are often forced to reduce or prematurely stop chemotherapy.
Nerve preservation
A thorny problem that psilocybin could avoid, the authors hope. They became interested in its effect on neuropathy almost by chance: while studying how cancer hijacks the nervous system to progress in mice, they discovered that the substance seemed to prevent the onset of this side effect.
Subsequent experiments have highlighted its role in protecting sensory nerves and stimulating, within them, the transport of mitochondria, the "powerhouses" of cells.
A key element, because chemotherapy destroys the "« rails »"microscopic which allow the latter to carry energy to the tips of the hands and feet, causing the death of nerve endings at these extremities.
Psilocybin also appears to act on the brain, notably preserving its electrical activity which is impaired by chemotherapy.
Administering two doses of this psychedelic substance before treatment was sufficient to prevent the development of painful hypersensitivity in rodents for up to six consecutive cycles of chemotherapy. And all this without disrupting either the immune system or the anti-tumor action of the treatment.
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Beware of self-medication
This discovery is "« very promising«,” Kristy Townsend, a professor of neurobiology at Ohio State University, who did not participate in the study, told AFP.
Moreover, the protective effect of psilocybin does not appear to be linked to its hallucinogenic effects: a non-hallucinogenic version of the molecule has demonstrated the same effect in the laboratory, she points out.
However, before it can be considered for inclusion in patient care protocols, further studies will be needed, particularly on humans.« to ensure its effectiveness and safety«", warns Ms. Townsend.
Researchers hope that this is a long process which should, however, be facilitated by the growth in medical research on psychedelic substances and the lifting of restrictions in this regard announced by the Trump administration in April.
The University of Texas MD Anderson Cancer Center will launch a clinical trial on cancer patients this fall, scheduled to last until 2031.
In the meantime, be careful not to give in to the temptation of self-medication, the authors insist.
Because although psilocybin consumption is legal in a handful of US states, this substance has an effect "« amplifier »"And taking it without proper supervision could considerably worsen the patient's condition, already emotionally affected by cancer," warns psychiatrist Gregory Jones, who also participated in the study.
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