Psilocybin prevents chemotherapy side effects…Two doses before treatment prevent neuropathy

A study found that giving two doses of psilocybin, a compound in hallucinogenic mushrooms, before chemotherapy can prevent peripheral neuropathy, a common side effect of cancer treatment, for an extended period.

According to a study published on the 3rd in the international journal Science, a research team led by Moran Amit of The University of Texas MD Anderson Cancer Center found that psilocybin can prevent chemotherapy-induced peripheral neuropathy (CIPN).

CIPN is a complication of cancer treatment that causes numbness and burning in the hands and feet, as well as heightened sensitivity to cold. Symptoms can persist for years, leading clinicians to reduce the dose of or discontinue life-saving chemotherapy. However, no preventive measures have been validated to date.

The research team reported that in mice, just two doses of psilocybin before chemotherapy prevented pain sensitivity from developing throughout eight chemotherapy cycles and an 8-month follow-up period. It did not affect the anticancer effect.

Psilocybin exerted its protective effect by activating serotonin 2A receptors (5-HT2A) in sensory neurons. The effect was unrelated to its hallucinogenic properties, and nonhallucinogenic 5-HT2A agonists showed the same efficacy.

The protective mechanism involves two pathways, peripheral and central. In the peripheral pathway, psilocybin activated a signaling pathway to maintain active transport of mitochondria within axons. This prevented chemotherapy from cutting off the energy supply to nerve endings, preserving tactile function and the density of nerve fibers in the skin.

In the central pathway, it normalized cortical electrical activity disrupted by chemotherapy, stabilizing synaptic function and brain-wave rhythms. Results from human donor sensory neurons, nerves isolated from surgical patients and patient skin biopsies also confirmed that this protective network is preserved in humans.

The research team said the findings shift CIPN from a condition to be treated to one to be prevented. Psilocybin already has clinical safety evidence, and nonhallucinogenic alternatives could avoid psychoactive risks, the team said.

However, the research team added that current evidence is limited to mouse models and human tissue studied in vitro, and that rigorous clinical trials are needed before the findings can be applied to patients.