Most everyone has had the experience of biting into a spicy pepper and feeling heat permeate their mouth. This feeling comes from the activation of TRPV (pronounced trip-vee) receptors. These are ion channels that sense stimuli like heat, pressure, light, acidity, herbs, and toxins. TRPV receptors exist on many kinds of cells — from taste buds to neurons. A recent article by a team of Italian scientists in Frontiers in Neurology examined the role of TRPV1 in multiple sclerosis, a neurodegenerative disease for which cannabis extracts are used in many countries. Activating TRPV1, even with potent toxins like resiniferatoxin, reduced the release of inflammatory chemicals by immune cells in the brain, thus reducing harms in a cellular model of multiple sclerosis. The scientists also examined 132 patients with MS, finding that mutations in the TRPV1 receptor was associated with neuroinflammation. Oddly enough, activating TRPV1 is usually associated with pain and inflammation (think pepper spray or a spider bite). It may be that activation of this receptor leads to long-term desensitization, which is why the researchers found a protective effect. Plant cannabinoids like THC, CBD, and CBC (cannabichromene) both activate and desensitize many TRP channels.
Adrian Devitt-Lee, Project CBD's chief science writer, is employed as a research chemist by the University College of London.