Cannabinoids are the natural compounds in the cannabis plant that interact with the body's endocannabinoid system. Despite largely hearing about CBD (cannabidiol) and THC (tetrahydrocannabinol) there are actually many more minor cannabinoids in the plant, but their impact on health has largely been undiscovered.
Now a new Canadian study from the Pharmacy and Nutrition unit at the University of Saskatchewan, Saskatoon has attempted to categorise and assign activities to some of these cannabinoids both in vitro and in vivo. For the in vitro part of the study the cannabinoids were tested at the CB1 and CB2 cannabinoid receptor sites of Chinese hamster ovary cells and for the in vivo part cannabinoids were administered to mice
The teams assessed the activity of 8 cannabinoids: these were THC and CBD as well as six minor cannabinoids, namely tetrahydrocannabinolic acid (THCA), tetrahydrocannabivarin (THCV), cannabidiolic acid (CBDA), cannabidivarin (CBDV), cannabigerol (CBG), and cannabichromene (CBC).
The results showed differential binding to CH1 and C2 along lines already reported: all eight cannabinoids tested had some level of binding to CB1 but, other than for THC, this binding was weak. Most of the cannabinoids also bound to CB2, including THC, but CBD bound poorly to this receptor.
In the mice, they found that THC, THCA, and THCV—but not CBD—reduced pain, while THC, CBD, THCA, THCV, and CBG all had a positive impact on anxiety.
The authors concluded THCA and THCV, which bound both CB1 and CB2, may be able to reduce pain, inflammation, and anxiety when either is used in the absence of other cannabinoids. This finding is significant since there is a growing interest in the clinical applications of single-cannabinoid preparations.
However the authors say that further study is warranted to see what other receptors other than just CB1 and CB2 might be important. They also commented that cannabis is a special case compared with most pharmaceuticals that have single active ingredients.
“Cannabis products contain many phytomolecules that are co-administered when Cannabis is consumed. This study represents an initial foray into potential between- and among-biomolecule interactions that can be built upon gradually. Pharmacology is a reductionist approach to biochemical interactions that cannot always model the complex interactions occurring in nature”.
The National Institute for Health is already investigating various minor cannabinoids and terpenes in cannabis for their pain-relieving benefits; it was announced in September 2019.