Cannabinoid and cannabinoid-like receptors in microglia, astrocytes and astrocytomas

“…compounds targeting cannabinoid-like receptors constitute promising therapeutics to manage neuroinflammation and eradicate malignant astrocytomas.

Importantly, the selective targeting of cannabinoid-like receptors should provide therapeutic relieve without inducing the typical psychotropic effects and possible addictive properties…

 Taken together, the studies outlined in this review suggest that stereotactic injection of high concentrations of CBD could constitute a useful regimen for neurosurgeons to use in the treatment of malignant astrocytomas and of excessive/chronic neuroinflammation.

Such a treatment could provide therapeutic effects both directly, by killing the astrocytoma and limiting its propagation, and indirectly, by reducing the accumulation of activated microglia or invading peripheral immune cells.

The fact that non-psychotropic cannabinoids acting through CB-like receptors affect such fundamental processes involved in microglial cell activation and astrocytoma propagation constitutes, in my opinion, one of the most exciting areas of research in our search for new chemotherapeutic agents to treat malignant brain tumors and new anti-inflammatory agents to temper the damage linked to chronic neuroinflammation.

Furthermore, the curative properties of cannabinoids do not overlap with currently available medicines, and therefore cannabinoid-based treatments constitute a new therapeutic platform.”

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2919281/

Cannabinoid receptors in human astroglial tumors.

“…cannabinoids are reported to inhibit the growth of tumors, including gliomas. These effects have been claimed to be mediated via cannabinoid receptors 1 and 2 (CB1, CB2).

We conclude that cannabinoid therapy of human gliomas targets not only receptors on tumor, but also on other cell types…”

http://www.ncbi.nlm.nih.gov/pubmed/16893424

Use of Dronabinol for Cannabis Dependence: Two Case Reports and Review

“Based on recent laboratory studies, dronabinol (delta-9-tetrahydrocannabinol) has been shown to reduce cannabis withdrawal symptoms and the subjective effects of marijuana.

Given that agonist agents have been found to be effective for opiate and nicotine dependence, the clinical utility of dronabinol for cannabis dependence is a reasonable approach…

It is clear from the two cases that both patients found the induction onto dronabinol helpful.”

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2733248/

Dronabinol for the Treatment of Cannabis Dependence: A Randomized, Double-Blind, Placebo-Controlled Trial

“… there are no effective medications for cannabis dependence. The purpose of this study was to evaluate the safety and efficacy of dronabinol, a synthetic form of delta-9-tetrahydrocannabinol, a naturally occurring pharmacologically active component of marijuana, in treating cannabis dependence.

This is the first trial using an agonist substitution strategy for treatment of cannabis dependence. Dronabinol showed promise, it was well-tolerated, and improved treatment retention and withdrawal symptoms…

In conclusion, agonist substitution pharmacotherapy with dronabinol, a synthetic form of THC, showed promise for treatment of cannabis dependence, reducing withdrawal symptoms and improving retention in treatment…

The trial showed that among adult cannabis-dependent patients, dronabinol was well accepted, with good adherence and few adverse events.”

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3154755/

 

5-Lipoxygenase and anandamide hydrolase (FAAH) mediate the antitumor activity of cannabidiol, a non-psychoactive cannabinoid.

“It has been recently reported that cannabidiol (CBD), a non-psychoactive cannabinoid, is able to kill glioma cells, both in vivo and in vitro, independently of cannabinoid receptor stimulation.

…the present investigation indicates that CBD exerts its antitumoral effects through modulation of the LOX pathway and of the endocannabinoid system…”

http://www.ncbi.nlm.nih.gov/pubmed/18028339

Cannabinoids inhibit peptidoglycan-induced phosphorylation of NF-κB and cell growth in U87MG human malignant glioma cells.

“Nuclear factor (NF)-κB is the key transcription factor involved in the inflammatory responses, and its activation aggravates tumors. Peptidoglycan (PGN), a main cell wall component of Gram-positive bacteria, stimulates Toll-like receptor 2 (TLR-2) and activates a number of inflammatory pathways, including NF-κB…

Cannabinoids have been reported to exert anti-inflammatory and antitumor effects…

Our finding that cannabinoids suppress the NF-κB inflammatory pathway and cell growth via CB1 receptors in glioma cells provides evidence for the therapeutic potential of targeting cannabinoid receptors for the treatment of inflammation-dependent tumor progression.”

http://www.ncbi.nlm.nih.gov/pubmed/22842590

Cannabinoid type-1 receptor ligands, alone or in combination with cocaine, affect vigilance-related behaviors of marmoset monkeys.

“Endocannabinoids (eCB) have been functionally linked to cocaine’s rewarding effects.

…changes in CB1r function – alone and in combination with cocaine – affected stereotyped vigilance-related behaviors… further implicating the eCB system in the neurobiological mechanisms of cocaine addiction.”

http://www.ncbi.nlm.nih.gov/pubmed/24445195

Beyond radio-displacement techniques for Identification of CB1 Ligands: The First Application of a Fluorescence-quenching Assay.

“Cannabinoid type 1 Receptor (CB1) belongs to the GPCR family and it has been targeted, so far, for the discovery of drugs aimed at the treatment of neuropathic pain, nausea, vomit, and food intake disorders. Here, we present the development of the first fluorescent assay enabling the measurement of kinetic binding constants for CB1orthosteric ligands…

…a sustainable valid alternative to the expensive and environmental impacting radiodisplacement techniques and paves the way for an easy, fast and cheap high-throughput drug screening toward CB1 for identification of new orthosteric and allosteric modulators.”

http://www.ncbi.nlm.nih.gov/pubmed/24441508

Expression of cannabinoid receptor 2 and its inhibitory effects on synovial fibroblasts in rheumatoid arthritis.

“Recent studies have suggested immunomodulatory and anti-inflammatory effects of cannabinoid receptor 2 (CB2R) activation, which shows no psychoactivity…

These data suggest that CB2R may be a potential therapeutic target of RA.”

http://www.ncbi.nlm.nih.gov/pubmed/24440992

Pre- and postsynaptic type-1 cannabinoid receptors control the alterations of glutamate transmission in experimental autoimmune encephalomyelitis.

“Type-1 cannabinoid receptors (CB1R) are important regulators of the neurodegenerative damage in multiple sclerosis (MS) and in experimental autoimmune encephalomyelitis (EAE). In GABAergic striatal neurons, CB1R stimulation exerts protective effects by limiting inflammation…

Our results provide further evidence that CB1R are involved in EAE pathophysiology, and suggest that both pre- and postsynaptic alterations of glutamate transmission are important to drive excitotoxic neurodegeneration typical of this disorder.”

http://www.ncbi.nlm.nih.gov/pubmed/24440366