“Cannabis sativa, is also popularly known as marijuana, has been cultivated and used for recreational and medicinal purposes for many centuries.
The main psychoactive content in cannabis is Δ9-tetrahydrocannabinol (THC). In addition to plant cannabis sativa, there are two classes of cannabinoids—the synthetic cannabinoids (e.g., WIN55212–2) and the endogenous cannabinoids (eCB), anandamide (ANA) and 2-arachidonoylglycerol (2-AG).
The biological effects of cannabinoids are mainly mediated by two members of the G-protein-coupled receptor family, cannabinoid receptors 1 (CB1R) and 2 (CB2R). The endocannabinoids, cannabinoid receptors, and the enzymes/proteins responsible for their biosynthesis, degradation, and re-updating constitute the endocannabinoid system.
In recent decades, the endocannabinoid system has attracted considerable attention as a potential therapeutic target in numerous physiological conditions, such as in energy balance, appetite stimulation, blood pressure, pain modulation, embryogenesis, nausea and vomiting control, memory, learning and immune response, as well as in pathological conditions such as Parkinson’s disease, Huntington’s disease, Alzheimer’s disease, and multiple sclerosis.
The major goal of this Special Issue is to discuss and evaluate the current progress in cannabis and cannabinoid research in order to increase our understanding about cannabinoid action and the underlying biological mechanisms and promote the development cannabinoid-based pharmacotherapies.
“Major depressive disorder is a devastating psychiatric disease that afflicts up to 17% of the world’s population. Postmortem brain analyses and imaging studies of patients with depression have implicated basal lateral amygdala (BLA) dysfunction in the pathophysiology of depression. However, the circuit and molecular mechanisms through which BLA neurons modulate depressive behavior are largely uncharacterized. Here, in mice, we identified that BLA cholecystokinin (CCK) glutamatergic neurons mediated negative reinforcement via D2 medium spiny neurons (MSNs) in the nucleus accumbens (NAc) and that chronic social defeat selectively potentiated excitatory transmission of the CCKBLA-D2NAc circuit in susceptible mice via reduction of presynaptic cannabinoid type-1 receptor (CB1R). Knockdown of CB1R in the CCKBLA-D2NAc circuit elevated synaptic activity and promoted stress susceptibility. Notably, selective inhibition of the CCKBLA-D2NAc circuit or administration of synthetic cannabinoids in the NAc was sufficient to produce antidepressant-like effects. Overall, our studies reveal the circuit and molecular mechanisms of depression.”
“Determining the mechanism of action (MOA) of novel or naturally occurring compounds mostly relies on assays tailored for individual target proteins.