Cannabidiol (CBD) is a phytocannabinoid with therapeutic properties for numerous disorders exerted through molecular mechanisms that are yet to be completely identified. CBD acts in some experimental models as an anti-inflammatory,
anticonvulsant,
anti-oxidant,
anti-emetic,
anxiolytic and
antipsychotic agent, and is therefore a potential medicine for the treatment of
neuroinflammation,
epilepsy, oxidative injury,
vomiting and
nausea, anxiety and
schizophrenia, respectively. The neuroprotective potential of CBD, based on the combination of its anti-inflammatory and
anti-oxidant properties, is of particular interest and is presently under intense preclinical research in numerous
neurodegenerative disorders. In fact, CBD combined with Δ(9)-tetrahydrocannabinol is already under clinical evaluation in patients with
Huntington's disease to determine its potential as a disease-modifying
therapy. The neuroprotective properties of CBD do not appear to be exerted by the activation of key targets within the
endocannabinoid system for plant-derived
cannabinoids like Δ(9)-tetrahydrocannabinol, i.e. CB(1) and CB(2) receptors, as CBD has negligible activity at these
cannabinoid receptors, although certain activity at the CB(2) receptor has been documented in specific pathological conditions (i.e. damage of immature brain). Within the
endocannabinoid system, CBD has been shown to have an inhibitory effect on the inactivation of
endocannabinoids (i.e. inhibition of FAAH
enzyme), thereby enhancing the action of these endogenous molecules on
cannabinoid receptors, which is also noted in certain pathological conditions. CBD acts not only through the
endocannabinoid system, but also causes direct or indirect activation of metabotropic receptors for
serotonin or
adenosine, and can target
nuclear receptors of the
PPAR family and also
ion channels.