Emerging role of cannabinoids and synthetic cannabinoid receptor 1/cannabinoid receptor 2 receptor agonists in cancer treatment and chemotherapy-associated cancer management

Journal of Cancer Research and Therapeutics“Cannabis was extensively utilized for its medicinal properties till the 19th century. A steep decline in its medicinal usage was observed later due to its emergence as an illegal recreational drug.

Advances in technology and scientific findings led to the discovery of delta-9-tetrahydrocannabinol (THC), the primary psychoactive compound of cannabis, that further led to the discovery of endogenous cannabinoids system consisting of G-protein-coupled receptors – cannabinoid receptor 1 and cannabinoid receptor 2 along with their ligands, mainly anandamide and 2-arachidonoylglycerol.  Endocannabinoid (EC) is shown to be a modulator not only for physiological functions but also for the immune system, endocrine network, and central nervous system.

Medicinal research and meta-data analysis over the last few decades have shown a significant potential for both THC and cannabidiol (CBD) to exert palliative effects. People suffering from many forms of advanced stages of cancers undergo chemotherapy-induced nausea and vomiting followed by severe and chronic neuropathic pain and weight loss.

THC and CBD exhibit effective analgesic, anxiolytic, and appetite-stimulating effect on patients suffering from cancer. Drugs currently available in the market to treat such chemotherapy-induced cancer-related ailments are Sativex (GW Pharmaceutical), Dronabinol (Unimed Pharmaceuticals), and Nabilone (Valeant Pharmaceuticals).

Apart from exerting palliative effects, THC also shows promising role in the treatment of cancer growth, neurodegenerative diseases (multiple sclerosis and Alzheimer’s disease), and alcohol addiction and hence should be exploited for potential benefits.

The current review discusses the nature and role of CB receptors, specific applications of cannabinoids, and major studies that have assessed the role of cannabinoids in cancer management.

Specific targeting of cannabinoid receptors can be used to manage severe side effects during chemotherapy, palliative care, and overall cancer management. Furthermore, research evidences on cannabinoids have suggested tumor inhibiting and suppressing properties which warrant reconsidering legality of the substance.

Studies on CB1 and CB2 receptors, in case of cancers, have demonstrated the psychoactive constituents of cannabinoids to be potent against tumor growth.

Interestingly, studies have also shown that activation of CB1 and CB2 cannabinoid receptors by their respective synthetic agonists tends to limit human cancer cell growth, suggesting the role of the endocannabinoid system as a novel target for treatment of cancers.

Further explorations are required to exploit cannabinoids for an effective cancer management.”

http://www.cancerjournal.net/preprintarticle.asp?id=263538

“Could Cannabis Kill Cancer Cells? A New Study Looks Promising”  https://www.portlandmercury.com/blogtown/2019/08/15/26977361/could-cannabis-kill-cancer-cells-a-new-study-looks-promising

“Study Reviews How Marijuana Compounds Inhibit Tumor Growth And Kill Cancer Cells” https://www.marijuanamoment.net/study-reviews-how-marijuana-compounds-inhibit-tumor-growth-and-kill-cancer-cells/

Facebook Twitter Pinterest Stumbleupon Tumblr Posterous

Δ9-Tetrahydrocannabinol suppresses monocyte-mediated astrocyte production of MCP-1 and IL-6 in a TLR7-stimulated human co-culture.

Journal of Pharmacology and Experimental Therapeutics“Cannabis is widely used in the United States with an estimated prevalence of 9.5%. Certain cannabinoids in Cannabis sativa, in particular, Δ9-tetrahydrocannabinol (THC), possess immune modulating and anti-inflammatory activity. Depending on the context, the anti-inflammatory activity of cannabinoids may be beneficial, such as in treating inflammatory diseases, or detrimental to normal immune defense against pathogens. The potential beneficial impact of cannabinoids on chronic neuroinflammation has gained recent attention. Monocyte migration to the brain has been implicated as a key event in chronic neuroinflammation and in the etiology of central nervous system diseases including viral infection (e.g., HIV-associated neurocognitive disorder). In the brain, monocytes can contribute to neuroinflammation through interactions with astrocytes, including inducing astrocyte secretion of cytokines and chemokines. In a human co-culture system, monocyte-derived IL-1β due to toll-like receptor 7 (TLR7)-activation, has been identified to promote astrocyte production of MCP-1 and IL-6. THC treatment of TLR7-stimulated co-culture suppressed monocyte secretion of IL-1β resulting in decreased astrocyte production of MCP-1 and IL-6. Furthermore, THC displayed direct inhibition of monocytes, as TLR7-stimulated monocyte monocultures treated with THC also showed suppressed IL-1β production. The cannabinoid receptor 2 (CB2) agonist, JWH-015, impaired monocyte IL-1β production similar to that of THC, suggesting THC is, in part, acting through CB2. THC also suppressed key elements of the IL-1β production pathway, including IL1B mRNA levels and caspase-1 activity. Collectively, this study demonstrates that the anti-inflammatory properties of THC suppress TLR7-induced monocyte secretion of IL-1β, through CB2, which results in decreased astrocyte secretion of MCP-1 and IL-6.

SIGNIFICANCE STATEMENT: As cannabis use is highly prevalent in the United States and has putative anti-inflammatory properties, it is important to investigate the effect of cannabinoids on immune cell function. Furthermore, cannabinoids have garnered particular interest due to their potential beneficial effects on attenuating viral-induced chronic neuroinflammation. This study utilized a primary human co-culture system to demonstrate that the major psychotropic cannabinoid in cannabis, Δ9-tetrahydrocannabinol (THC) and a cannabinoid receptor-2 (CB2) selective agonist, suppress specific monocyte-mediated astrocyte inflammatory responses. In the context of viral-induced chronic neuroinflammation, the findings presented here suggest that cannabinoids via CB2 ligation may have beneficial anti-inflammatory effects.”

https://www.ncbi.nlm.nih.gov/pubmed/31383729

http://jpet.aspetjournals.org/content/early/2019/08/05/jpet.119.260661

Facebook Twitter Pinterest Stumbleupon Tumblr Posterous

Therapeutic potential of cannabinoids as neuroprotective agents for damaged cells conducing to movement disorders.

International Review of Neurobiology“The basal ganglia (BG), an organized network of nuclei that integrates cortical information, play a crucial role in controlling motor function. In fact, movement disorders such as Parkinson’s disease (PD) and Huntington’s disease (HD) are caused by the degeneration of specific structures within the BG.

There is substantial evidence supporting the idea that cannabinoids may constitute novel promising compounds for the treatment of movement disorders as neuroprotective and anti-inflammatory agents.

This potential therapeutic role of cannabinoids is based, among other qualities, on their capacity to reduce oxidative injury and excitotoxicity, control calcium influx and limit the toxicity of reactive microglia.

The mechanisms involved in these effects are related to CB1 and CB2 receptor activation, although some of the effects are CB receptor independent.

Thus, taking into account the aforementioned properties, compounds that act on the endocannabinoid system could be useful as a basis for developing disease-modifying therapies for PD and HD.”

https://www.ncbi.nlm.nih.gov/pubmed/31349929

https://www.sciencedirect.com/science/article/pii/S0074774219300327?via%3Dihub

Facebook Twitter Pinterest Stumbleupon Tumblr Posterous

Modulators of the endocannabinoid system influence skin barrier repair, epidermal proliferation, differentiation and inflammation in a mouse model.

Experimental Dermatology banner“Endocannabinoids (ECs) are important regulators of cell signaling.

Cannabinoid receptors are involved in keratinocyte proliferation/differentiation.

Elevation of the endogenous cannabinoid tone leads to strong anti-inflammatory effects.

Here, we explored the influence of endocannabinoid system (ECS) modulators on skin permeability barrier repair, epidermal proliferation, differentiation and inflammation in hairless mice.

We used WOBE440, a selective fatty acid amide hydrolase (FAAH) inhibitor, WOL067-531, an inhibitor of endocannabinoid reuptake with no relevant FAAH activity, which both signal via cannabinoid receptor-1and 2 (CB-1R and CB-2R) and compared them to WOBE15 which signals via CB-2R.

We found that barrier repair was significantly delayed by WOL067-531.

In summary, we showed that WOL067-531 exhibits a significant effect on skin barrier repair, epidermal proliferation/differentiation and inflammation.”

https://www.ncbi.nlm.nih.gov/pubmed/31350927

https://onlinelibrary.wiley.com/doi/abs/10.1111/exd.14012

Facebook Twitter Pinterest Stumbleupon Tumblr Posterous

Targeting Cannabinoid Signaling in the Immune System: “High”-ly Exciting Questions, Possibilities, and Challenges

Image result for frontiers in immunology“It is well known that certain active ingredients of the plants of Cannabis genus, i.e., the “phytocannabinoids” [pCBs; e.g., (−)-trans9-tetrahydrocannabinol (THC), (−)-cannabidiol, etc.] can influence a wide array of biological processes, and the human body is able to produce endogenous analogs of these substances [“endocannabinoids” (eCB), e.g., arachidonoylethanolamine (anandamide, AEA), 2-arachidonoylglycerol (2-AG), etc.]. These ligands, together with multiple receptors (e.g., CB1 and CB2 cannabinoid receptors, etc.), and a complex enzyme and transporter apparatus involved in the synthesis and degradation of the ligands constitute the endocannabinoid system (ECS), a recently emerging regulator of several physiological processes. The ECS is widely expressed in the human body, including several members of the innate and adaptive immune system, where eCBs, as well as several pCBs were shown to deeply influence immune functions thereby regulating inflammation, autoimmunity, antitumor, as well as antipathogen immune responses, etc. Based on this knowledge, many in vitro and in vivo studies aimed at exploiting the putative therapeutic potential of cannabinoid signaling in inflammation-accompanied diseases (e.g., multiple sclerosis) or in organ transplantation, and to dissect the complex immunological effects of medical and “recreational” marijuana consumption. Thus, the objective of the current article is (i) to summarize the most recent findings of the field; (ii) to highlight the putative therapeutic potential of targeting cannabinoid signaling; (iii) to identify open questions and key challenges; and (iv) to suggest promising future directions for cannabinoid-based drug development.

Active Components of Cannabis sativa (Hemp)—Phytocannabinoids (pCBs) and Beyond

It is known since ancient times that consumption of different parts of the plant Cannabis sativa can lead to psychotropic effects. Moreover, mostly, but not exclusively because of its potent analgesic actions, it was considered to be beneficial in the management of several diseases. Nowadays it is a common knowledge that these effects were mediated by the complex mixture of biologically active substances produced by the plant. So far, at least 545 active compounds have been identified in it, among which, the best-studied ones are the so-called pCBs. It is also noteworthy that besides these compounds, ca. 140 different terpenes [including the potent and selective CB2 agonist sesquiterpene β-caryophyllene (BCP)], multiple flavonoids, alkanes, sugars, non-cannabinoid phenols, phenylpropanoids, steroids, fatty acids, and various nitrogenous compounds can be found in the plant, individual biological actions of which are mostly still nebulous. Among the so far identified > 100 pCBs, the psychotropic (−)-trans9-tetrahydrocannabinol (THC) and the non-psychotropic (−)-cannabidiol (CBD) are the best-studied ones, exerting a wide-variety of biological actions [including but not exclusively: anticonvulsive, analgesic, antiemetic, and anti inflammatory effects]. Of great importance, pCBs have been shown to modulate the activity of a plethora of cellular targets, extending their impact far beyond the “classical” (see above) cannabinoid signaling. Indeed, besides being agonists [or in some cases even antagonists of CB1 and CB2 cannabinoid receptors, some pCBs were shown to differentially modulate the activity of certain TRP channels, PPARs, serotonin, α adrenergic, adenosine or opioid receptors, and to inhibit COX and lipoxygenase enzymes, FAAH, EMT, etc.. Moreover, from a clinical point-of-view, it should also be noted that pCBs can indirectly modify pharmacokinetics of multiple drugs (e.g., cyclosporine A) by interacting with several cytochrome P 450 (CYP) enzymes. Taken together, pCBs can be considered as multitarget polypharmacons, each of them having unique “molecular fingerprints” created by the characteristic activation/inhibition pattern of its locally available cellular targets.

Concluding Remarks—Lessons to Learn from Cannabis

Research efforts of the past few decades have unambiguously evidenced that ECS is one of the central orchestrators of both innate and adaptive immune systems, and that pure pCBs as well as complex cannabis-derivatives can also deeply influence immune responses. Although, many open questions await to be answered, pharmacological modulation of the (endo)cannabinoid signaling, and restoration of the homeostatic eCB tone of the tissues augur to be very promising future directions in the management of several pathological inflammation-accompanied diseases. Moreover, in depth analysis of the (quite complex) mechanism-of-action of the most promising pCBs is likely to shed light to previously unknown immune regulatory mechanisms and can therefore pave new “high”-ways toward developing completely novel classes of therapeutic agents to manage a wide-variety of diseases.”

https://www.frontiersin.org/articles/10.3389/fimmu.2017.01487/full

www.frontiersin.org

Facebook Twitter Pinterest Stumbleupon Tumblr Posterous

Pharmacology of Medical Cannabis.

 “The Cannabis plant has been used for many of years as a medicinal agent in the relief of pain and seizures. It contains approximately 540 natural compounds including more than 100 that have been identified as phytocannabinoids due to their shared chemical structure. The predominant psychotropic component is Δ9-tetrahydrocannabinol (Δ9-THC), while the major non-psychoactive ingredient is cannabidiol (CBD). These compounds have been shown to be partial agonists or antagonists at the prototypical cannabinoid receptors, CB1 and CB2. The therapeutic actions of Δ9-THC and CBD include an ability to act as analgesics, anti-emetics, anti-inflammatory agents, anti-seizure compounds and as protective agents in neurodegeneration. However, there is a lack of well-controlled, double blind, randomized clinical trials to provide clarity on the efficacy of either Δ9-THC or CBD as therapeutics. Moreover, the safety concerns regarding the unwanted side effects of Δ9-THC as a psychoactive agent preclude its widespread use in the clinic. The legalization of cannabis for medicinal purposes and for recreational use in some regions will allow for much needed research on the pharmacokinetics and pharmocology of medical cannabis. This brief review focuses on the use of cannabis as a medicinal agent in the treatment of pain, epilepsy and neurodegenerative diseases. Despite the paucity of information, attention is paid to the mechanisms by which medical cannabis may act to relieve pain and seizures.”

https://www.ncbi.nlm.nih.gov/pubmed/31332738

https://link.springer.com/chapter/10.1007%2F978-3-030-21737-2_8

Facebook Twitter Pinterest Stumbleupon Tumblr Posterous

Cannabinoid Interactions with Proteins: Insights from Structural Studies.

 “Cannabinoids have been widely used for recreational and medicinal purposes. The increasing legalization of cannabinoid use and the growing success in Medicinal Chemistry of cannabinoids have fueled recent interest in cannabinoid-sensing sites in receptor proteins. Here, we review structural data from high-resolution cryo-EM and crystallography studies that depict phytocannabinoid, endocannabinoid, and synthetic cannabinoid molecules bound to various proteins. The latter include antigen-binding fragment (Fab), cellular retinol binding protein 2 (CRBP2), fatty acid-binding protein 5 (FABP5), peroxisome proliferator-activated receptor γ (PPAR γ), and cannabinoid receptor types 1 and 2 (CB1 and CB2). Cannabinoid-protein complexes reveal the complex design of cannabinoid binding sites that are usually presented by conventional ligand-binding pockets on respective proteins. However, subtle differences in cannabinoid interaction with amino acids within the binding pocket often result in diverse consequences for protein function. The rapid increase in available structural data on cannabinoid-protein interactions will ultimately direct drug design efforts toward rendering highly potent cannabinoid-related pharmacotherapies that are devoid of side effects.”

https://www.ncbi.nlm.nih.gov/pubmed/31332733

https://link.springer.com/chapter/10.1007%2F978-3-030-21737-2_3

Facebook Twitter Pinterest Stumbleupon Tumblr Posterous

Cannabinoid system involves in the analgesic effect of protocatechuic acid.

 “Protocatechuic acid is an antioxidant which is shown to have analgesic activity in limited studies. However, the mechanisms of action remain unclear.

OBJECTIVES:

It is aimed to investigate the possible contribution of cannabinoid system that supresses the nociceptive process by the activation of CB1 and CB2 receptors in central and peripheral levels of pain pathways, to the analgesic activity of protocatechuic acid.

RESULTS:

It was determined that protocatechuic acid has dose-dependent analgesic effect independently from locomotor activity and is comparable with effects of dipyrone and WIN 55,212-2. Pre-treatment with CB1 receptor antagonist AM251 significantly antagonized the protocatechuic acid-induced analgesia in the tail-immersion and writhing tests, whereas pre-treatment of CB2 receptor antagonist AM630 was found to be effective only in the tail-immersion test.

CONCLUSION:

It is concluded that cannabinoid modulation contributes to the analgesic effect of protocatechuic acid in spinal level rather than peripheral. CB1 receptor stimulation rather than CB2 receptor stimulation mediates the analgesic effect of protocatechuic acid in both levels, especially peripheral. Graphical abstract Protocatechuic acid inhibits pain response via cannabinoidergic system.”

https://www.ncbi.nlm.nih.gov/pubmed/31325037

https://link.springer.com/article/10.1007/s40199-019-00288-x

“Protocatechuic acid (PCA) is a dihydroxybenzoic acid, a type of phenolic acid. It is a major metabolite of antioxidant polyphenols found in green tea.”  https://en.wikipedia.org/wiki/Protocatechuic_acid

Facebook Twitter Pinterest Stumbleupon Tumblr Posterous

Distinct Functions of Endogenous Cannabinoid System in Alcohol Abuse Disorders.

British Journal of Pharmacology banner

“Δ9-tetrahydrocannabinol (Δ9 -THC), the principal active component in Cannabis sativa extracts such as marijuana, participates in cell signaling by binding to cell surface receptors. CB1 receptors (CB1 s) are present in both inhibitory and excitatory presynaptic terminals. CB2 receptors (CB2 s) found in neuronal subpopulations in addition to microglial cells and astrocytes and are present in both pre- and postsynaptic terminals.

Subsequent to endocannabinoid (eCB) system discoveries, studies have suggested that alcohol alters the eCB system and that the eCB system plays a major role in the motivation to abuse alcohol.

Preclinical studies have provided evidence that chronic alcohol consumption modulates eCBs and CB1 expression in brain addiction circuits. In addition, studies have further established the distinct function of the eCB system in the development of fetal alcohol spectrum disorders. This review provides a recent and comprehensive assessment of the literature related to the function of the eCB system in alcohol abuse disorders.”

https://www.ncbi.nlm.nih.gov/pubmed/31265740

https://bpspubs.onlinelibrary.wiley.com/doi/abs/10.1111/bph.14780

“Cannabis and Alcohol: From Basic Science to Public Policy.”  https://www.ncbi.nlm.nih.gov/pubmed/31265135

Facebook Twitter Pinterest Stumbleupon Tumblr Posterous

Omega-3 Endocannabinoid-Epoxides Are Novel Anti-inflammatory and Anti-Pain Lipid Metabolites (FS15-01-19).

Issue Cover“Omega-3 fatty acid derived endocannabinoids are metabolized by cytochrome P450s to form bioactive endocannabinoid epoxides that are anti-inflammatory.

RESULTS:

Cannabinoids are found in marijuana and also are produced naturally in the body from ω-3 and ω-6 fatty acids. Exocannabinoids in marijuana, are known to be responsible for some of its euphoric effects, but they also exhibit anti-inflammatory benefits. Our study revealed a cascade of enzymatic reactions that convert ω-3 fatty acids into anti-inflammatory endocannabinoid epoxides that act through the same receptors in the body as marijuana (PNAS 2017).

Endocannabinoids are ligands for cannabinoidreceptor 1 and 2 (CB1 and CB2). CB1 receptor agonists exhibit psychotropic properties while CB2 receptor agonists have anti-inflammatory effects. Consequently, there is a strong interest in the discovery of CB2 selective agonists to mitigate inflammatory pathologies. The work details the discovery and characterization of naturally occurring ω-3-derived endocannabinoid epoxides that are formed via enzymatic oxidation of ω-3 endocannabinoids by cytochrome P450 epoxygenases. These dual functional ω-3 endocannabinoid epoxides exhibit preference towards binding to CB2 receptor and are anti-inflammatory and vasodilatory and reciprocally modulate platelet aggregation. Some of the other regioisomers of ω-3 endocannabinoid epoxides are partial agonists of CB1 and stop tumor cell metastasis (J. Med. Chem 2018). By virtue of their physiological properties, they are expected to play important roles in neuroinflammation and pain.

CONCLUSIONS:

This finding demonstrates how omega-3 fatty acids can produce some of the same medicinal qualities as marijuana, but without a psychotropic effect. In summary, the ω-3 endocannabinoid epoxides are found at concentrations comparable to those of other endocannabinoids and are expected to play critical roles during inflammation in vivo.”

https://www.ncbi.nlm.nih.gov/pubmed/31223777

https://academic.oup.com/cdn/article/3/Supplement_1/nzz031.FS15-01-19/5518049

Facebook Twitter Pinterest Stumbleupon Tumblr Posterous