Purpose of review: Here, we overview the latest findings from studies investigating the skeletal endocannabinoid (EC) system and its involvement in bone formation and resorption.
Recent findings: The endocannabinoid system consists of endogenous ligands, receptors, and enzymes. The main cannabinoids found in the cannabis plant are Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD). Cannabinoid receptors CB1 and CB2 are expressed in bone and regulate bone homeostasis in rodents and humans. CBD treatment was shown to enhance fracture healing in rats. Recent studies in mice indicate that strain, age, and sex differences dictate the skeletal outcome of the EC activation. CBD treatment was shown to enhance bone healing, but needs validation in clinical trials. While research shows that EC activity protects against bone loss, studies on CB1 and CB2 agonists in bone regeneration models are lacking. Whether modulating the EC system would affect bone repair remains therefore an open question worth investigating.
Keywords: Bone, CB1 receptor, CB2 receptor, CBD, Cannabinoid, Cannabis, Endocannabinoid, Fracture, Osteoporosis, Skeleton