The formalin may have helped produce some of the bone-strengthening collagen crosslinking the researchers were attributing to the CBD, Nyman said. Even though this was done for all test subjects, he said the study was too small to say whether the formalin affected them equally and didn’t change the study outcome.
Robert Glatter, MD, who directs the emergency sports medicine program at Lenox Hill Hospital in New York City, expressed similar sentiments.
Gabet and his team methodically broke the rats’ femurs and administered THC, CBD, or a ethanol/emulphor/saline solution that served as a control to see how well the rats’ bones healed over eight weeks using 3D micro-computed tomography and biomechanical machines. As part of a second experiment, they tried a mixture of THC and CBD, THC alone and CBD alone. The third experiment in the study involved measuring how THC and CBD affected the enzymes that prompt collagen crosslinking in healing bones, and the researchers reported that CBD enhanced expression of the enzyme lysyl hydroxylase 1, or PLOD 1.
— Forget the headlines you read. Here’s what you should know.
“Implicating PLOD 1 in the mechanism of action of CBD may have far-reaching significances, beyond the improvement of fracture healing, in instances such as Ehlers-Danlos syndrome, bronchopulmonary dysplasia, bicuspid aortic wall-associated aneurisms, and cancer metastases,” wrote the authors, who included the so-called “grandfather of marijuana,” Raphael Mechoulam, PhD.
by Sydney Lupkin, Reporter, VICE News/MedPage Today July 23, 2015
“It’s very clear to me that this is not accelerated healing,” Nyman said.
Gabet and his team said that while they didn’t measure long term effects, previous studies have shown CBD to be safe.
Cannabinoid ligands regulate bone mass, but skeletal effects of cannabis (marijuana and hashish) have not been reported. Bone fractures are highly prevalent, involving prolonged immobilization and discomfort. Here we report that the major non-psychoactive cannabis constituent, cannabidiol (CBD), enhances the biomechanical properties of healing rat mid-femoral fractures. The maximal load and work-to-failure, but not the stiffness, of femurs from rats given a mixture of CBD and Δ(9) -tetrahydrocannabinol (THC) for 8 weeks were markedly increased by CBD. This effect is not shared by THC (the psychoactive component of cannabis), but THC potentiates the CBD stimulated work-to-failure at 6 weeks postfracture followed by attenuation of the CBD effect at 8 weeks. Using micro-computed tomography (μCT), the fracture callus size was transiently reduced by either CBD or THC 4 weeks after fracture but reached control level after 6 and 8 weeks. The callus material density was unaffected by CBD and/or THC. By contrast, CBD stimulated mRNA expression of Plod1 in primary osteoblast cultures, encoding an enzyme that catalyzes lysine hydroxylation, which is in turn involved in collagen crosslinking and stabilization. Using Fourier transform infrared (FTIR) spectroscopy we confirmed the increase in collagen crosslink ratio by CBD, which is likely to contribute to the improved biomechanical properties of the fracture callus. Taken together, these data show that CBD leads to improvement in fracture healing and demonstrate the critical mechanical role of collagen crosslinking enzymes.
Keywords: CANNABIDIOL; COLLAGEN CROSSLINKING; FRACTURE HEALING; FTIR; LYSYL HYDROXYLASE; μCT.