A study on mice has revealed a moss-like plant has a similar effects on the body as tetrahydrocannabinol (THC), the psychoactive ingredient in cannabis.
Liverwort, a member of the bryophytes family of plants, was found to tap into the body’s endocannabinoid system similarly to THC when it creates a high.
In the U.S., tetrahydrocannabinol is available in the drug dronabinol to treat nausea and vomiting in cancer patients undergoing chemotherapy, and appetite and weight loss in AIDs patients. More than half of U.S. states and the District of Columbia have legalized medical marijuana. But the Food and Drug Administration (FDA) has refused to back it as a treatment citing a lack of scientific evidence to prove it is effective.
Previously, evidence suggested cannabis was the only plant which contained THC. But in 1994, Japanese chemist Yoshinori Asakawa found atoms in the liverwort plant were tied together similarly to THC and named the molecule perrottetinene.
In recent years, liverworts have been marketed online as cannabis-like legal highs which are smoked by users but no research has been done into their effects.
A team of scientists in Switzerland consequently identified perrottetinene as ripe for investigation in regards to whether it resembled THC chemically and produced similar pharmacological effects.
Since low levels of perrottetinene are present in liverwort, the team synthesized the molecule and used the substance to conduct experiments in mice models and in cells.
This enabled the researchers to compare the chemical structures of THC and perrottetinene, as well as the changes it caused in mice. They published their findings in the journal Science Advances.
Dr. Jürg Gertsch, study author and professor at the Institute of Biochemistry and Molecular Medicine at the University of Bern, told Newsweek the study is important because it not only shows a plant other than cannabis produces a variant of THC but that perrottetinene is also bioactive in the brain.
That could explain why the drug is smoked as a so-called legal high.
Perrottetinene was also found to behave like an endogenous cannabinoid—or a form of the chemical originating from the body—and had an effect on inflammatory factors in the brain by plugging into cannabinoid receptors, unlike THC from cannabis.
Dr. Karen Wright, Lecturer in Biomedical Sciences in the Faculty of Health and Medicine at Lancaster University who did not work on the study told Newsweek she was surprised to learn that cannabinoids are not unique to the cannabis plant and that the molecule had the same effect as THC, albeit with higher doses.
Commenting on the finding that the molecule reduced the production of an inflammatory mediator in the brain, she said: “The implications of this are unknown. It could mean it has anti-inflammatory potential in an inflammatory setting, but could also mean that some key homeostatic function in the brain (or body) is reduced too, with unknown consequences.”
She warned that any compounds that bind to CB1 receptor in the brain, as THC does, “will always come with some issues around the impact on mental health and brain development,” particularly in young people.
“Even though this compound, when smoked, is unlikely to produce the high associated with cannabis, methods to extract and concentrate it could reveal the same problems.”
“And we’re far from liverwort replacing medical marijuana, argued Wright. “Rather it should enter a phase of preclinical study in disease models,” she said.
The study is the latest to unpick the potential medical uses of cannabis. Last week, a study published in the journal JAMA Network Open found medical marijuana could be used to treat the symptoms of multiple sclerosis.
Scientists reached their conclusion following a meta-analysis of 17 existing clinical trials involving 3,161 patients the degenerative condition who took products containing a form of cannabinoid.