Scientists from the University of Bern and ETH Zurich have, for the first time, investigated the pharmacological effects of a compound found in a rare moss called liverwort. The compound closely resembles that of THC, but exhibits less of a psychoactive effect with potentially better anti-inflammatory properties.

While several plants other than marijuana are known to produce cannabinoids, cannabis is the only plant so far discovered to contain THC, the primary psychoactive compound generally associated with a "high." In the 1990s scientists discovered that a liverwort plant called Radula perrottetii contained a natural compound with an extraordinary structural similarity to THC.

This natural compound, dubbed perrottetinene, underpinned anecdotal reports suggesting this particular genus of liverwort moss could be an effective "legal high." However, the actual pharmacological effects of this unique compound have never been investigated.

In a new published study, scientists for the first time have homed in on the pharmacological effects of perrottetinene, discovering it does indeed activate the same cannabinoid receptors in the brain as THC, albeit with a significantly reduced psychoactive potency. Perhaps most interesting was the revelation that perrottetinene shows similar anti-inflammatory actions in the brain to THC, although some fundamentally different pharmacological actions were also identified, suggesting it may confer better medical outcomes than its more psychoactive counterpart.

Due to the low concentrations of perrottetinene found naturally in the liverwort moss, the researchers developed a new synthesis method to effectively produce large amounts of the substance without having to isolate it from the natural plant. Michael Schafroth, one of the authors of the study, notes the new synthesis technique developed in the research will further broaden study into the mechanisms and effects of cannabinoids.

"The present study is a prime example of how new synthetic concepts can make a contribution towards enriching our pharmacological knowledge of biologically-active natural substances," says Schafroth.

Any potential clinical applications arising from this new research are undoubtedly many years away, with a great deal of work still to be done to better understand this novel compound and uncover what uses it could have in medical contexts. Nevertheless, this promising discovery may offer up a pathway towards treatments that can harness the unique medical benefits of THC without its overwhelming psychoactive effects.

The study was published in the journal Science Advances.