Tag Archives: CB1

The Highs and Lows of the Endocannabinoid System—Another Piece to the Epilepsy Puzzle?

Posted on by
Reply

American Epilepsy Society

“Cannabis extracts have been used for the treatment of epilepsy for centuries.

Yet, until recently, this empirical use was not linked to a known mechanism of action. Of the two main and most frequently investigated compounds derived from the cannabis plant, the mechanism of action of tetrahydrocannabinol (THC) is relatively clear and well documented (via CB1R distributed mainly centrally and CB2R distributed mainly peripherally).

The components of endocannabinoid system (ECS) are omnipresent in our bodies and have very divergent roles. Modulating ECS may have therapeutic potential in many human maladies, including psychiatric disorders (e.g., depression, posttraumatic stress disorder, anxiety, or schizophrenia), neurologic conditions, including epilepsy and neurodegenerative processes, diabetes and its complications, obesity, pain management, cancer treatment, graft versus host disease, treatment of chemotherapy side effects, and so on. The list is long, and it is constantly growing.

We investigated changes in the endocannabinoid system and glucose metabolism during temporal lobe epileptogenesis.

This study provides unique evidence that the CB1R is dynamically and progressively involved from the start of mesial temporal lobe epileptogenesis.”

http://epilepsycurrents.org/doi/10.5698/1535-7597.18.5.315

Anandamide Effects in a Streptozotocin-Induced Alzheimer’s Disease-Like Sporadic Dementia in Rats.

Posted on by
Reply

Image result for frontiers in neuroscience

“Alzheimer’s disease (AD) is characterized by multiple cognitive deficits including memory and sensorimotor gating impairments as a result of neuronal and synaptic loss.

The endocannabinoid system plays an important role in these deficits but little is known about its influence on the molecular mechanism regarding phosphorylated tau (p-tau) protein accumulation – one of the hallmarks of AD -, and on the density of synaptic proteins.

Thus, the aim of this study was to investigate the preventive effects of anandamide (N-arachidonoylethanolamine, AEA) on multiple cognitive deficits and on the levels of synaptic proteins (syntaxin 1, synaptophysin and synaptosomal-associated protein, SNAP-25), cannabinoid receptor type 1 (CB1) and molecules related to p-tau degradation machinery (heat shock protein 70, HSP70), and Bcl2-associated athanogene (BAG2) in an AD-like sporadic dementia model in rats using intracerebroventricular (icv) injection of streptozotocin (STZ).

This study showed, for the first time, that the administration of an endocannabinoid can prevent AD-like effects induced by STZ, boosting further investigations about the modulation of endocannabinoid levels as a therapeutic approach for AD.”

 https://www.ncbi.nlm.nih.gov/pubmed/30333717
“Altogether, our results showed, for the first time, that the administration of an endocannabinoid can prevent cognitive, synaptic and histopatological AD-like alterations induced by STZ, thus prompting endocannabinoids as a candidate therapeutic target in AD.”  https://www.frontiersin.org/articles/10.3389/fnins.2018.00653/full

Translational potential of allosteric modulators targeting the cannabinoid CB1 receptor.

Posted on by
Reply

Image result for aps acta pharmacologica

“The cannabinoid type-1 (CB1) receptor, a G-protein-coupled receptor, is an attractive target for drug discovery due to its involvement in many physiological processes. Historically, drug discovery efforts targeting the CB1 receptor have focused on the development of orthosteric ligands that interact with the active site to which endogenous cannabinoids bind. Research performed over the last several decades has revealed substantial difficulties in translating CB1 orthosteric ligands into druggable candidates. The difficulty is mainly due to the adverse effects associated with orthosteric CB1 ligands. Recent discoveries of allosteric CB1 modulators provide tremendous opportunities to develop CB1 ligands with novel mechanisms of action; these ligands may potentially improve the pharmacological effects and enhance drug safety in treating the disorders by regulating the functions of the CB1 receptor. In this paper, we review and summarize the complex pharmacological profiles of each class of CB1 allosteric modulators, the development of new classes of CB1 allosteric modulators and the results from in vivo assessments of their therapeutic value.”

 https://www.ncbi.nlm.nih.gov/pubmed/30333554
https://www.nature.com/articles/s41401-018-0164-x

Structure-Based Identification of Potent Natural Product Chemotypes as Cannabinoid Receptor 1 Inverse Agonists.

Posted on by
Reply

molecules-logo

“Natural products are an abundant source of potential drugs, and their diversity makes them a rich and viable prospective source of bioactive cannabinoid ligands.

Cannabinoid receptor 1 (CB1) antagonists are clinically established and well documented as potential therapeutics for treating obesity, obesity-related cardiometabolic disorders, pain, and drug/substance abuse, but their associated CNS-mediated adverse effects hinder the development of potential new drugs and no such drug is currently on the market. This limitation amplifies the need for new agents with reduced or no CNS-mediated side effects.

We are interested in the discovery of new natural product chemotypes as CB1 antagonists, which may serve as good starting points for further optimization towards the development of CB1 therapeutics.

Most importantly, these bioactive compounds represent structurally new natural product chemotypes in the area of cannabinoid research and could be considered for further structural optimization as CB1 ligands.”

https://www.ncbi.nlm.nih.gov/pubmed/30322136

https://www.mdpi.com/1420-3049/23/10/2630

Atypical Pharmacodynamic Properties and Metabolic Profile of the Abused Synthetic Cannabinoid AB-PINACA: Potential Contribution to Pronounced Adverse Effects Relative to Δ9-THC

Posted on by
Reply

Image result for frontiers in pharmacology

“Recreational use of marijuana is associated with few adverse effects, but abuse of synthetic cannabinoids (SCBs) can result in anxiety, psychosis, chest pain, seizures and death.

To potentially explain higher toxicity associated with SCB use, we hypothesized that AB-PINACA, a common second generation SCB, exhibits atypical pharmacodynamic properties at CB1 cannabinoid receptors (CB1Rs) and/or a distinct metabolic profile when compared to Δ9-tetrahydrocannabinol (Δ9-THC), the principal psychoactive cannabinoid present in marijuana.

Taken collectively, the atypical pharmacodynamic properties of AB-PINACA at CB1Rs relative to Δ9-THC (e.g., higher potency/efficacy and greater production of desensitization), coupled with an unusual metabolic profile (e.g., production of metabolically stable active phase I metabolites) may contribute to the pronounced adverse effects observed with abuse of this SCB compared to marijuana.

““K2” or “Spice” is a popular drug of abuse that is heavily marketed to young teens and first-time drug users as “safe” and/or “legal” marijuana”. Most K2 preparations consist of plant materials laced with a mixture of one or more SCB compounds possessing psychoactive properties similar to those produced by Δ9-tetrahydrocannabinol (Δ9-THC), the principal psychoactive compound found in marijuana. However, in contrast to the low incidence of adverse effects reported following use of marijuana, recreational abuse of SCBs can additionally result in anxiety, psychosis, chest pain, seizures and death.

In marked contrast to K2/Spice products, marijuana contains only a single psychoactive compound Δ9-THC and a second natural constituent known as cannabidiol, that appears to blunt adverse effects produced by Δ9-THC. In fact, the beneficial combination of cannabidiol with Δ9-THC led to development of Sativex, a drug currently in clinical trials to treat a variety of indications including spasticity associated with multiple sclerosis.

In addition to Δ9-THC and cannabidiol, the cannabis plant contains hundreds of other phytocannabinoids and constituents not present in K2/Spice products that may help mitigate harmful and/or adverse effects ”

https://www.ncbi.nlm.nih.gov/pubmed/30319418

https://www.frontiersin.org/articles/10.3389/fphar.2018.01084/full

Neural stem cell lineage-specific cannabinoid type-1 receptor regulates neurogenesis and plasticity in the adult mouse hippocampus.

Posted on by
Reply

Cerebral Cortex

“Neural stem cells (NSCs) in the adult mouse hippocampus occur in a specific neurogenic niche, where a multitude of extracellular signaling molecules converges to regulate NSC proliferation as well as fate and functional integration. However, the underlying mechanisms how NSCs react to extrinsic signals and convert them to intracellular responses still remains elusive.

NSCs contain a functional endocannabinoid system, including the cannabinoid type-1 receptor (CB1).

To decipher whether CB1 regulates adult neurogenesis directly or indirectly in vivo, we performed NSC-specific conditional inactivation of CB1 by using triple-transgenic mice.

These results demonstrate that CB1 expressed in NSCs and their progeny controls neurogenesis in adult mice to regulate the NSC stem cell pool, dendritic morphology, activity-dependent plasticity, and behavior.”

https://www.ncbi.nlm.nih.gov/pubmed/30307491

https://academic.oup.com/cercor/advance-article/doi/10.1093/cercor/bhy258/5126794

Genetic and pharmacological regulation of the endocannabinoid CB1 receptor in Duchenne muscular dystrophy.

Posted on by
Reply

 Nature Communications

“The endocannabinoid system refers to a widespread signaling system and its alteration is implicated in a growing number of human diseases.

However, the potential role of endocannabinoids in skeletal muscle disorders remains unknown. Here we report the role of the endocannabinoid CB1 receptors in Duchenne’s muscular dystrophy.

In murine and human models, CB1 transcripts show the highest degree of expression at disease onset, and then decline overtime. Similar changes are observed for PAX7, a key regulator of muscle stem cells. Bioinformatics and biochemical analysis reveal that PAX7 binds and upregulates the CB1 gene in dystrophic more than in healthy muscles.

Rimonabant, an antagonist of CB1, promotes human satellite cell differentiation in vitro, increases the number of regenerated myofibers, and prevents locomotor impairment in dystrophic mice.

In conclusion, our study uncovers a PAX7-CB1 cross talk potentially exacerbating DMD and highlights the role of CB1 receptors as target for potential therapies.”

https://www.ncbi.nlm.nih.gov/pubmed/30262909

“We propose that the endocannabinoid system participates in the development of degenerative muscle disease, through effects on muscle differentiation, regeneration, and repair processes, and suggest that CB1 receptor may represent a potential target for the adjuvant therapy of muscle dystrophies.”

https://www.nature.com/articles/s41467-018-06267-1

Repeated Cannabidiol treatment reduces cocaine intake and modulates neural proliferation and CB1R expression in the mouse hippocampus.

Posted on by
Reply

Neuropharmacology

“Cannabinoid derivatives have shown promising results for treating neuropsychiatric disorders, including drug addiction.

Recent studies on the therapeutic effects of Cannabidiol (CBD) on drug abuse showed mixed results, especially with psychostimulant substances such as cocaine. To determine whether CBD can attenuate cocaine reinforcement, we assessed behavioural responses induced by cocaine in mice, using the behavioural sensitization, conditioned place preference and intravenous self-administration paradigms.

We show that repeated CBD treatment produces anxiolytic effects in the elevated plus maze test, increases the discrimination index of the novel object recognition task and attenuates cocaine-induced conditioned place preference but does not affect behavioural sensitization.

CBD reduced cocaine voluntary consumption and progressive ratio breaking point in the self-administration paradigm, but not drug-induced reinstatement. In parallel, CBD increased expression of type 1 cannabinoid receptor, MAPK-CREB phosphorylation, BDNF expression, and neural cell proliferation in the hippocampus, and reduced the GluA1/2 AMPA subunit receptor ratio in the striatum.

In summary, we show that CBD can modulate some behavioural and molecular manifestations of cocaine reinforcement. Moreover, our findings show that CBD has pro-neurogenic effects also in cocaine consuming animals.

Overall, this novel evidence provides new perspectives to use CBD as a therapeutic tool.”

https://www.ncbi.nlm.nih.gov/pubmed/30273593

https://www.sciencedirect.com/science/article/pii/S0028390818307135?via%3Dihub

Bortezomib And Endocannabinoid/Endovanilloid System: A Synergism In Osteosarcoma.

Posted on by
Reply

Pharmacological Research

“Osteosarcoma is the most common primary malignant tumor of bone in children and adolescents.

Bortezomib (BTZ) is an approved anticancer drug, classified as a selective reversible inhibitor of the ubiquitin-dependent proteasome system, that leads to cancer cell cycle arrest and apoptosis reducing the invasion ability of Osteosarcoma cells in vitro. It also regulates the RANK/RANKL/OPG system, involved in the pathogenesis of bone tumors and in cell migration.

A side effect of BTZ is to induce painful sensory peripheral neuropathy which lead to cessation of therapy or dose reduction.

Recently BTZ has been evaluated in combination with Cannabinoids targeting CB1 receptor, demonstrating a promising synergic effect.

The Endocannabinoid/Endovanilloid (EC/EV) system includes two G protein-coupled receptors (CB1 and CB2), the Transient Potential Vanilloid 1 (TRPV1) channel and their endogenous ligands and enzymes.

CB1 and CB2 are expressed mainly in Central Nervous System and Immune Peripheral cells respectively. TRPV1 is also expressed in primary sensory neurons and is involved in pain modulation.

EC/EV system induces apoptosis, reduces invasion and cell proliferation in Osteosarcoma cell lines and is involved in bone metabolism.

We analyzed the effects of BTZ, alone and in combination with selective agonists at CB2 (JWH-133) and TRPV1 (RTX) receptors, in the Osteosarcoma cell line (HOS) on Apoptosis, Cell Cycle progression, migration and bone balance. We observed that the stimulation of CB2 and TRPV1 receptors increase the efficacy of BTZ in inducing apoptosis and reducing invasion, cell cycle progression and by modulating bone balance.

These data suggest the possibility to use BTZ, in combination with EC/EV agonists, in Osteosarcoma therapy reducing its dose and its side effects.”

https://www.ncbi.nlm.nih.gov/pubmed/30267762

https://www.sciencedirect.com/science/article/abs/pii/S1043661818310387

Cannabinoid 1 Receptor Signaling on Hippocampal GABAergic Neurons Influences Microglial Activity.

Posted on by
Reply

Image result for frontiers in molecular neuroscience

“Microglia, the resident immune cells of the brain, play important roles in defending the brain against pathogens and supporting neuronal circuit plasticity. Chronic or excessive pro-inflammatory responses of microglia damage neurons, therefore their activity is tightly regulated.

Pharmacological and genetic studies revealed that cannabinoid type 1 (CB1) receptor activity influences microglial activity, although microglial CB1 receptor expression is very low and activity-dependent. The CB1 receptor is mainly expressed on neurons in the central nervous system (CNS)-with an especially high level on GABAergic interneurons.

Here, we determined whether CB1 signaling on this neuronal cell type plays a role in regulating microglial activity.

Our result suggests that CB1 receptor agonists can modulate microglial activity indirectly, through CB1 receptors on GABAergic neurons.

Altogether, we demonstrated that GABAergic neurons, despite their relatively low density in the hippocampus, have a specific role in the regulation of microglial activity and cannabinoid signaling plays an important role in this arrangement.”

https://www.ncbi.nlm.nih.gov/pubmed/30210289

https://www.frontiersin.org/articles/10.3389/fnmol.2018.00295/full