Cannabinoid CB2 Receptors Regulate Central Sensitization and Pain Responses Associated with Osteoarthritis of the Knee Joint.

“Osteoarthritis (OA) of the joint is a prevalent disease accompanied by chronic, debilitating pain. Recent clinical evidence has demonstrated that central sensitization contributes to OA pain. An improved understanding of how OA joint pathology impacts upon the central processing of pain is crucial for the identification of novel analgesic targets/new therapeutic strategies.

Inhibitory cannabinoid 2 (CB2) receptors attenuate peripheral immune cell function and modulate central neuro-immune responses in models of neurodegeneration…

These findings suggest that targeting CB2 receptors may have therapeutic potential for treating OA pain.”

http://www.ncbi.nlm.nih.gov/pubmed/24282543

Endocannabinoid system and pain: an introduction.

“The endocannabinoid (EC) system consists of two main receptors: cannabinoid type 1 receptor cannabinoid receptors are found in both the central nervous system (CNS) and periphery, whereas the cannabinoid type 2 receptor cannabinoid receptor is found principally in the immune system and to a lesser extent in the CNS.

 The EC family consists of two classes of well characterised ligands; the N-acyl ethanolamines, such as N-arachidonoyl ethanolamide or anandamide (AEA), and the monoacylglycerols, such as 2-arachidonoyl glycerol. The various synthetic and catabolic pathways for these enzymes have been (with the exception of AEA synthesis) elucidated.

 To date, much work has examined the role of EC in nociceptive processing and the potential of targeting the EC system to produce analgesia.

Cannabinoid receptors and ligands are found at almost every level of the pain pathway from peripheral sites, such as peripheral nerves and immune cells, to central integration sites such as the spinal cord, and higher brain regions such as the periaqueductal grey and the rostral ventrolateral medulla associated with descending control of pain. EC have been shown to induce analgesia in preclinical models of acute nociception and chronic pain states.

 The purpose of this review is to critically evaluate the evidence for the role of EC in the pain pathway and the therapeutic potential of EC to produce analgesia. We also review the present clinical work conducted with EC, and examine whether targeting the EC system might offer a novel target for analgesics, and also potentially disease-modifying interventions for pathophysiological pain states.”

http://www.ncbi.nlm.nih.gov/pubmed/24148358

Cannabinoids ameliorate disease progression in a model of multiple sclerosis in mice, acting preferentially through CB1 receptor-mediated anti-inflammatory effects

“Cannabinoids have been proposed as promising therapeutic agents in MS given their capability to alleviate specific MS symptoms (e.g., spasticity, pain).

Although MS has been considered mainly an inflammatory disorder, recent evidence, however, revealed the importance of neurodegenerative events, opening the possibility that cannabinoid agonists, given their cytoprotective properties, may also serve to reduce oligodendrocyte death and axonal damage in MS.

Thus, the treatment with WIN55,512-2, a potent CB1 and CB2 agonist, was reported to be effective to ameliorate tremor and spasticity in mice with chronic relapsing experimental autoimmune encephalomyelitis, a murine model of MS, but also to delay disease progression in this and other murine models of MS….”

http://www.sciencedirect.com/science/article/pii/S0028390812000500

Control of Spasticity in a Multiple Sclerosis Model is mediated by CB1, not CB2, Cannabinoid Receptors

Figure 1

“There is increasing evidence to suggest that cannabis can ameliorate muscle-spasticity in multiple sclerosis, as was objectively shown in experimental autoimmune encephalomyelitis models. The purpose of this study was to investigate further the involvement of CB1 and CB2 cannabinoid receptors in the control of experimental spasticity…

Conclusions and Implications:

The CB1 receptor controls spasticity and cross-reactivity to this receptor appears to account for the therapeutic action of some CB2 agonists.

 As cannabinoid-induced psychoactivity is also mediated by the CB1 receptor, it will be difficult to truly dissociate the therapeutic effects from the well-known, adverse effects of cannabinoids when using cannabis as a medicine.

The lack of knowledge on the true diversity of the cannabinoid system coupled with the lack of total specificity of current cannabinoid reagents makes interpretation of in vivo results difficult, if using a purely pharmacological approach.

Gene knockout technology provides an important tool in target validation and indicates that the CB1 receptor is the main cannabinoid target for an anti-spastic effect.”

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2189718/

Control of spasticity in a multiple sclerosis model using central nervous system-excluded CB1 cannabinoid receptor agonists.

“The purpose of this study was the generation of central nervous system (CNS)-excluded cannabinoid receptor agonists to test the hypothesis that inhibition of spasticity, due to CNS autoimmunity, could be controlled by affecting neurotransmission within the periphery…

In summary, CNS-excluded CB1 receptor agonists are a novel class of therapeutic agent for spasticity.”

http://www.ncbi.nlm.nih.gov/pubmed/24121462

Critical appraisal of the potential use of cannabinoids in cancer management

“Cannabinoids have been attracting a great deal of interest as potential anticancer agents. Originally derived from the plant Cannabis sativa, there are now a number of endo-, phyto- and synthetic cannabinoids available. This review summarizes the key literature to date around the actions, antitumor activity, and mechanisms of action for this broad range of compounds…

Two therapeutic avenues exist for the development of cannabinoids as anticancer agents. As antiemetic and analgesic compounds, this class of compounds has been explored in terms of palliative care. More recently, cannabinoid agonists and antagonists have been screened for potential direct antitumorigenic properties.

… results suggest that overall the cannabinoids affect multiple cellular signaling pathways, which means they have the potential to decrease cancer development, growth, and metastasis.

Overall, the cannabinoids may show future promise in the treatment of cancer, but there are many significant hurdles to be overcome. There is much still to be learned about the action of the cannabinoids and the endocannabinoid system.

It is a distinct possibility that the cannabinoids may have a place in the future treatment of cancer.”

Full Text: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3770515/

Immunomodulatory and therapeutic effects of Hot-nature diet and co-supplemented hemp seed, evening primrose oils intervention in multiple sclerosis patients.

“Multiple sclerosis (MS) is the most chronic and inflammatory disorder. Because of limited efficacy and adverse side effects, identifying novel therapeutic and protective agents is important. This study was aimed to assess the potential therapeutic effects of hemp seed and evening primrose oils as well as Hot-nature dietary intervention on RRMS patients…

CONCLUSION:

The co-supplemented hemp seed and evening primrose oils with Hot-nature diet have beneficial effects in improving of clinical score in RRMS patients which were confirmed by immunological findings.”

http://www.ncbi.nlm.nih.gov/pubmed/24050582

Cannabidiol-Induced Apoptosis in Human Leukemia Cells: A Novel Role of Cannabidiol in the Regulation of p22phox and Nox4 Expression

“Marijuana has been suggested as a potent therapeutic agent alleviating such complications as intraocular pressure in glaucoma and cachexia, nausea, and pain in AIDS and cancer patients. A number of recent studies now suggest the possible use of these compounds for the treatment of cannabinoid receptor-expressing tumors…

In the current study, we examined the effects of the nonpsychoactive cannabinoid, cannabidiol, on the induction of apoptosis in leukemia cells. Exposure of leukemia cells to cannabidiol led to cannabinoid receptor 2 (CB2)-mediated reduction in cell viability and induction in apoptosis. Furthermore, cannabidiol treatment led to a significant decrease in tumor burden and an increase in apoptotic tumors in vivo…

Together, the results from this study reveal that cannabidiol, acting through CB2 and regulation of Nox4 and p22phox expression, may be a novel and highly selective treatment for leukemia…

In summary, the current study demonstrates that CBD-induced apoptosis may constitute a novel approach to treat malignancies of the immune system…”

Full text: http://molpharm.aspetjournals.org/content/70/3/897.long

Cannabidiol, unlike synthetic cannabinoids, triggers activation of RBL-2H3 mast cells

“Plant-derived cannabinoids, such as Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD), the main psychoactive and nonpsychoactive components of cannabis, respectively, possess myriad pharmacological properties…

Cannabidiol (CBD), a prominent psychoinactive component of cannabis with negligible affinity for known cannabinoid receptors, exerts numerous pharmacological actions, including anti-inflammatory and immunosuppressive effects…

Together, these results support existence of yet-to-be identified sites of interaction, i.e., receptors and/or ion channels associated with Ca2+ influx of natural cannabinoids such as CBD and THC, the identification of which has the potential to provide for novel strategies and agents of therapeutic interest.”

Full text: http://www.jleukbio.org/content/81/6/1512.long

Therapeutic potential of cannabinoid medicines.

Drug Testing and Analysis

“Cannabis was extensively used as a medicine throughout the developed world in the nineteenth century but went into decline early in the twentieth century ahead of its emergence as the most widely used illicit recreational drug later that century. Recent advances in cannabinoid pharmacology alongside the discovery of the endocannabinoid system (ECS) have re-ignited interest in cannabis-based medicines.

The ECS has emerged as an important physiological system and plausible target for new medicines. Its receptors and endogenous ligands play a vital modulatory role in diverse functions including immune response, food intake, cognition, emotion, perception, behavioural reinforcement, motor co-ordination, body temperature, wake/sleep cycle, bone formation and resorption, and various aspects of hormonal control. In disease it may act as part of the physiological response or as a component of the underlying pathology.

In the forefront of clinical research are the cannabinoids delta-9-tetrahydrocannabinol and cannabidiol, and their contrasting pharmacology will be briefly outlined. The therapeutic potential and possible risks of drugs that inhibit the ECS will also be considered. This paper will then go on to review clinical research exploring the potential of cannabinoid medicines in the following indications: symptomatic relief in multiple sclerosis, chronic neuropathic pain, intractable nausea and vomiting, loss of appetite and weight in the context of cancer or AIDS, psychosis, epilepsy, addiction, and metabolic disorders.”

http://www.ncbi.nlm.nih.gov/pubmed/24006213

http://onlinelibrary.wiley.com/doi/10.1002/dta.1529/abstract