Do cannabinoids have a therapeutic role in transplantation?

Figure 1

“Cannabinoids are a group of terpenophenolic compounds structurally similar to delta-9-tetrahydrocannabinol (THC) from the plant Cannabis sativa.

Cannabinoids have emerged as powerful drug candidates for the treatment of inflammatory and autoimmune diseases due to their immunosuppressive properties.

Significant clinical and experimental data on the use of cannabinoids as anti-inflammatory agents exist in many autoimmune disease settings, but virtually no studies have been undertaken on their potential role in transplant rejection. Here we suggest a theoretical role for the use of cannabinoids in preventing allograft rejection.

…manipulation of endocannabinoids in vivo by activating their biosynthesis and inhibiting cellular uptake and metabolism may offer another pathway to regulate immune response during allograft rejection.

…cannabinoids have emerged as novel anti-inflammatory agents because of their efficacy in the treatment of many immune-mediated disorders such as multiple sclerosis, rheumatoid arthritis and autoimmune hepatitis.

Transplantation is one critical area of medicine that requires the use of immunosuppressants.

 Inasmuch as, immune cells constitute an important resource of endocannabinoids, it may be easier to manipulate their levels during an immune response, which could have a direct and immediate impact on such cells that determine the fate of the allograft.

In summary, targeting cannabinoid receptors and understanding the role and use of exo-and endocannabinoids in experimental allograft rejection models may provide an exciting new beginning with significant translational impact.”

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2923447/

Signaling through cannabinoid receptor 2 suppresses murine dendritic cell migration by inhibiting matrix metalloproteinase 9 expression

“The cannabinoid system consists of cannabinoid receptors and their ligands, including endocannabinoids, synthetic cannabinoid receptor agonists and antagonists, and phytocannabinoids.

Administration of cannabinoid receptor 2 (CB2R) agonists in inflammatory and autoimmune disease and CNS injury models results in significant attenuation of clinical disease, and reduction of inflammatory mediators.

…cannabinoids contribute to resolve acute inflammation and to reestablish homeostasis.

Selective CB2R agonists might be valuable future therapeutic agents for the treatment of chronic inflammatory conditions by targeting activated immune cells, including DCs.

Because of their anti-inflammatory functions targeting various immune cells, CB2R agonists could represent valuable therapeutic agents for the treatment of chronic inflammatory conditions.”

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3488886/

Cannabinoid receptor 2: potential role in immunomodulation and neuroinflammation.

Figure 2

“The cannabinoids are a group of terpenophenolic compounds present in the marijuana plant, Cannabis sativa. At present, three general types of cannabinoids have been identified: phytocannabinoids present uniquely in the cannabis plant, endogenous cannabinoids produced in humans and animals, and synthetic cannabinoids generated in a laboratory. It is worth noting that Cannabis sativa produces over 80 cannabinoids…

An accumulating body of evidence suggests that endocannabinoids and cannabinoid receptors type 1 and 2 (CB(1), CB(2)) play a significant role in physiologic and pathologic processes, including cognitive and immune functions.

…there is growing appreciation of the therapeutic potential of cannabinoids in multiple pathologic conditions involving chronic inflammation (inflammatory bowel disease, arthritis, autoimmune disorders, multiple sclerosis, HIV-1 infection, stroke, Alzheimer’sdisease to name a few), mainly mediated by CB(2) activation.

This review attempts to summarize recent advances in studies of CB(2) activation in the setting of neuroinflammation, immunomodulation and HIV-1 infection.

The full potential of CB2 agonists as therapeutic agents remains to be realized.

Despite some inadequacies of preclinical models to predict clinical efficacy in humans and differences between the signaling of human and rodent CB2 receptors, the development of selective CB2 agonists may open new avenues in therapeutic intervention.

Such interventions would aim at reducing the release of pro-inflammatory mediators particularly in chronic neuropathologic conditions such as HAND or MS.”

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3663904/

 

Attenuation of experimental autoimmune hepatitis by exogenous and endogenous cannabinoids: involvement of regulatory T cells.

Fig. 1

“Immune-mediated liver diseases including autoimmune and viral hepatitis are a major health problem worldwide. Natural cannabinoids such as Delta(9)-tetrahydrocannabinol (THC) effectively modulate immune cell function, and they have shown therapeutic potential in treating inflammatory diseases.

We investigated the effects of THC in a murine model of concanavalin A (ConA)-induced hepatitis…

Our data demonstrate that targeting cannabinoid receptors using exogenous or endogenous cannabinoids and use of FAAH inhibitors may constitute novel therapeutic modalities to treat immune-mediated liver inflammation.

δ-9-Tetrahydrocannabinol (THC), the major psychoactive component of marijuana (Cannabis sativa), has wide-ranging pharmacological properties. The cannabinoid compounds possess significant immunosuppressive and anti-inflammatory properties. THC and cannabinoid receptor agonists have shown promise in several models of inflammation.”

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2828293/

Role of Myeloid-Derived Suppressor Cells in Amelioration of Experimental Autoimmune Hepatitis Following Activation of TRPV1 Receptors by Cannabidiol

Figure 1

“Myeloid-derived suppressor cells (MDSCs) are getting increased attention as one of the main regulatory cells of the immune system. They are induced at sites of inflammation and can potently suppress T cell functions. In the current study, we demonstrate how activation of TRPV1 vanilloid receptors can trigger MDSCs, which in turn, can inhibit inflammation and hepatitis…

This study demonstrates for the first time that MDSCs play a critical role in attenuating acute inflammation in the liver, and that agents such as CBD, which trigger MDSCs through activation of TRPV1 vanilloid receptors may constitute a novel therapeutic modality to treat inflammatory diseases.

Cannabidiol (CBD) is a major non-psychoactive cannabinoid component of marijuana.

Together, these studies not only demonstrate that CBD can protect the host from acute liver injury but also provide evidence for the first time that MDSCs may play a critical role in protecting the liver from acute inflammation.

Non-psychoactive cannabinoids such as CBD possess great therapeutic potential in treating various inflammatory liver diseases, including autoimmune hepatitis.”

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3069975/

Targeting the cannabinoid pathway limits the development of fibrosis and autoimmunity in a mouse model of systemic sclerosis.

Figure 1

“Our aim was to evaluate the roles of the cannabinoid pathway in the induction and propagation of systemic sclerosis (SSc) in a mouse model…

Experiments performed in CB2-deficient mice confirmed the influence of CB2 in the development of systemic fibrosis and autoimmunity. Therefore, we demonstrate that the CB2 receptor is a potential target for the treatment of SSc because it controls both skin fibroblast proliferation and the autoimmune reaction.

In this report, we demonstrate for the first time the highly protective role of cannabinoid agonists in SSc. Because these agonists are available and well-tolerated under clinical conditions, our data offer a new therapeutic opportunity in this life-threatening disease.

In conclusion, modulation of the endocannabinoid system is a novel approach for the treatment of various inflammatory diseases.”

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2893662/

Immunoactive effects of cannabinoids: considerations for the therapeutic use of cannabinoid receptor agonists and antagonists

Figure 1

“The active constituents of Cannabis sativa have been used for centuries as recreational drugs and medicinal agents. Today, marijuana is the most prevalent drug of abuse in the United States and, conversely, therapeutic use of marijuana constituents are gaining mainstream clinical and political acceptance.

Given the documented contributions of endocannabinoid signaling to a range of physiological systems, including cognitive function, and the control of eating behaviors, it is unsurprising that cannabinoid receptor agonists and antagonists are showing significant clinical potential.

In addition to the neuroactive effects of cannabinoids, an emerging body of data suggests that both endogenous and exogenous cannabinoids are potently immunoactive.

The central premise of this review article is that the immunological effects of cannabinoids should be considered in the context of each prescribing decision.

We present evidence that the immunological effects of cannabinoid receptor agonists and antagonists are highly relevant to the spectrum of disorders for which cannabinoid therapeutics are currently offered.

Therapeutically relevant cannabinoid receptor ligands include tetra-hydrocannabinol itself, its synthetic forms, and its closely related compounds.

As a final point, the application of CB1 antagonists may be immunostimulative…”

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3804300/

Updating the chemistry and biology of cannabinoid CB2 receptor-specific inverse agonists.

“The cannabinoid CB(2) receptor continues to be an intriguing target for the potential therapeutic benefit of cannabinoids. Because this receptor is significantly found outside the brain, compounds specific for the CB(2) receptor may be free of the side effects that have plagued cannabinoid CB(1) receptor-based therapeutics.

In this review, we will discuss a class of compounds which modulate the constitutive activity of the cannabinoid CB(2) receptor, the inverse agonists. We will discuss recent chemical advances that provide new compounds to investigate the biology based on this pharmacology. We will then discuss new biology associated with the cannabinoid CB(2) receptor for hints of how these compounds can best be utilized in vivo.”

http://www.ncbi.nlm.nih.gov/pubmed/20370714

Biology and therapeutic potential of cannabinoid CB2 receptor inverse agonists

Figure 2

“Evidence has emerged suggesting a role for the cannabinoid CB2 receptor in immune cell motility. This provides a rationale for a novel and generalized immunoregulatory role for cannabinoid CB2 receptor-specific compounds…

An ability to control the migration of inflammatory cells to the site of insult is a powerful strategy for the development of immunomodulators. Our work on triaryl bis-sulphones suggest that the cannabinoid CB2 receptor-specific inverse agonists may serve as such immune modulators…

Further studies, using these and other CB2 receptor-specific compounds, will be required to resolve the complex pharmacology of cannabinoids and the cannabinoid CB2 receptor, and to determine the most effective pharmacology to exploit this therapeutic target.”

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2219522/

Cannabinoid Modulation of Neuroinflammatory Disorders

Table 1.

Cannabis sativa is a herb belonging to the Cannabaceae family, characterized by palmate leaves and numerous fibers. Its first record as a medicine dates back to 5000 years ago and it was found in China, where cannabis was used for a myriad of purposes and diseases, including malaria, neuropathic pain, nausea, sexual dysfunction and constipation.

The use of cannabis spread from Central Asia and deeply influenced Indian folk medicine. However, sedative and psychotropic effects of cannabis turned it into a recreational drug. This fact resulted in discrimination against the consumption of the cannabis plant and its derivatives, which delayed the scientific findings in this field…

In recent years, a growing interest has been dedicated to the study of the endocannabinoid system. The isolation of Cannabis sativa main psychotropic compound, Δ(9)-tetrahydrocannabinol (THC), has led to the discovery of an atypical neurotransmission system that modulates the release of other neurotransmitters and participates in many biological processes, including the cascade of inflammatory responses.

In this context, cannabinoids have been studied for their possible therapeutic properties in neuroinflammatory diseases. In this review, historic and biochemical aspects of cannabinoids are discussed, as well as their function as modulators of inflammatory processes and therapeutic perspectives for neurodegenerative disorders, particularly, multiple sclerosis.

Cannabinoid compounds may be extracted from the plant (phytocannabinoids) or be artificially obtained (synthetic cannabinoids)…

To date, it is still impossible to prove or rule out all benefits of cannabis described empirically by ancient herbal practitioners. For now, science aims to understand how cannabinoid compounds are associated with neuroinflammation and how cannabis-based medicine can help millions of patients worldwide.”

 http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3386505/