Cannabinoid Pharmacology in Neurological Therapeutics

Cannabinoids exert their actions through a complex interplay with the endocannabinoid system, comprising G-protein-coupled receptors, endogenous ligands and metabolic enzymes. In the central nervous system, the cannabinoid receptor 1 (CB1) predominates and modulates neurotransmitter release, synaptic plasticity and neuronal excitability. The peripheral receptor 2 (CB2) is expressed on microglia and infiltrating immune cells, where it shapes neuroinflammatory responses. Exogenous phytocannabinoids such as Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD) differ in receptor affinity and functional profile; THC acts as a partial agonist at CB1 and CB2, whereas CBD shows low receptor affinity but influences endocannabinoid tone and engages non-canonical targets. This pharmacological diversity has spurred investigations into neuroprotective, anticonvulsant and anti-inflammatory applications. Modulation of receptor signalling pathways, inhibition of inflammatory cascades and promotion of neurogenesis underlie the therapeutic rationale for conditions ranging from epilepsy and chronic pain to neurodegenerative and psychiatric disorders. Translational studies have advanced selective receptor modulators, signalling-biased ligands and holistic preparations, each offering distinct safety and efficacy profiles. Practical challenges include heterogeneous bioavailability, psychoactive side effects and the need to disentangle multi-target mechanisms. Emerging analytical methods and biased agonism are refining drug design, while preclinical and clinical trials continue to define optimal dosing, formulation and patient selection.

Research from Nature Portfolio

One recent clinical development introduced a signalling-specific inhibitor of the CB1 receptor that selectively attenuates a subset of intracellular cascades triggered by THC binding without eliciting overt behavioural effects. Early-phase trials demonstrated safety, good tolerability and dose-dependent reductions in self-administration of cannabis and positive subjective effects, suggesting potential utility in treating substance use disorders and related neurological impairments. A complementary foundational study profiled a panel of CB2 receptor ligands, revealing marked differences in signalling bias and off-target activities. This work identified a small set of agonists optimally suited for probing CB2-mediated immunomodulation, laying the groundwork for targeted therapies in neuroinflammatory and neurodegenerative conditions.

Cannabinoid Pharmacology in Neurological Therapeutics publication trend

The graph below shows the total number of articles in cannabinoid pharmacology in neurological therapeutics across all publications each year (not limited to Nature Index journals).

Technical terms

CB1 receptor: A G-protein-coupled receptor in the central nervous system that modulates neurotransmitter release and synaptic function.

CB2 receptor: A receptor expressed chiefly on immune and glial cells that regulates neuroinflammation and immune responses.

Endocannabinoid: An endogenous lipid mediator, such as anandamide, that activates cannabinoid receptors.

NLRP3 inflammasome: A multiprotein complex in immune cells that governs activation of pro-inflammatory cytokines.

TRP channels: A family of ionotropic receptors that mediate cellular responses to thermal, chemical and mechanical stimuli.

References

1. Signaling-specific inhibition of the CB1 receptor for cannabis use disorder: phase 1 and phase 2a randomized trials. Nature Medicine (2023).
2. FDA-approved cannabidiol [Epidiolex®] alleviates Gulf War Illness-linked cognitive and mood dysfunction, hyperalgesia, neuroinflammatory signaling, and declined neurogenesis. Military Medical Research (2024).
3. Phytocannabinoids: a unified critical inventory. Natural Product Reports (2016).
4. Cannabinoid Receptors and the Endocannabinoid System: Signaling and Function in the Central Nervous System. International Journal of Molecular Sciences (2018).
5. The CB2 receptor and its role as a regulator of inflammation. Cellular and Molecular Life Sciences (2016).
6. Cannabinoid Ligands Targeting TRP Channels. Frontiers in Molecular Neuroscience (2019).
7. Cannabinoid CB2 receptor ligand profiling reveals biased signalling and off-target activity. Nature Communications (2017).