According to basic research of scientists of the National Centre for Scientific Research in Valbonne, France, cannabidiol (CBD) may prevent the development of prion diseases, the most known being BSE (bovine spongiforme enzephalopathy), which is often called mad cow disease. It is believed that the BSE may be transmitted to human beings. In humans, it is known as Creutzfeldt-Jakob disease.

The infectious agent in prion diseases is believed to be a specific type of misfolded protein called prion. Misfolded prion proteins carry the disease between individuals and cause deterioration of the brain. The French researchers reported that the non- psychoactive cannabis constituent CBD inhibited the accumulation of prion proteins in both mouse and sheep prion- infected cells, whereas other cannabinoids were either weak or not effective. Moreover, after infection with mouse scrapie, a prion disease, CBD limited accumulation of the prion protein in the brain and significantly increased the survival time of infected mice. CBD inhibited the nerve damaging effects of prions in a concentration-dependent manner. Researchers noted that CBD may be a promising agent for the treatment of prion diseases.

(Source: Dirikoc S, Priola SA, Marella M, Zsuerger N, Chabry J. Nonpsychoactive cannabidiol prevents prion accumulation and protects neurons against prion toxicity. J Neurosci 2007;27(36):9537-44.)

Prion diseases are transmissible neurodegenerative disorders characterized by the accumulation in the CNS of the protease-resistant prion protein (PrPres), a structurally misfolded isoform of its physiological counterpart PrPsen. Both neuropathogenesis and prion infectivity are related to PrPres formation. Here, we report that the nonpsychoactive cannabis constituent cannabidiol (CBD) inhibited PrPres accumulation in both mouse and sheep scrapie-infected cells, whereas other structurally related cannabinoid analogs were either weak inhibitors or noninhibitory. Moreover, after intraperitoneal infection with murine scrapie, peripheral injection of CBD limited cerebral accumulation of PrPres and significantly increased the survival time of infected mice. Mechanistically, CBD did not appear to inhibit PrPres accumulation via direct interactions with PrP, destabilization of PrPres aggregates, or alteration of the expression level or subcellular localization of PrPsen. However, CBD did inhibit the neurotoxic effects of PrPres and affected PrPres-induced microglial cell migration in a concentration-dependent manner. Our results suggest that CBD may protect neurons against the multiple molecular and cellular factors involved in the different steps of the neurodegenerative process, which takes place during prion infection. When combined with its ability to target the brain and its lack of toxic side effects, CBD may represent a promising new anti-prion drug.